Tendernotice 1
Tendernotice 1
Tendernotice 1
TENDER SPECIFICATION
FOR
SEMI DRY FLUE GAS DESULPHURIZATION
(FGD) SYSTEM & ITS AUXILIARIES
VOLUME – II A
GENERAL
TECHNICAL SPECIFICATION
MECON LIMITED
RANCHI – 834 002
INDEX TO VOLUMES
Volumes Title
Volume – I Commercial
Volume – II Technical
Volume - IIA General Technical Specification
Section 01.00 Preamble
Section 02.00 Intent of specification
Section 03.00 Project information
Section 04.00 Special Instructions to Bidder
Section 05.00 Scope of Work, Supply & Services
Section 06.00 Quality Assurance System / Requirement
Section 07.00 Painting
Section 08.00 Finalization of Sub-vendors / Sub-contractors
Section 09.00 Performance Guarantees
Section 10.00 Terminal Points & Exclusion
Section 11.00 Layout and Maintenance Requirement
Section 12.00 Drawings / Documents to be submitted along with Bid / Offer
and after award of contract
Volume - IIB Technical Specification
Section 01.00 Flue Gas Desulphurization System (Semi Dry)
Section 02.00 Technical Data Sheets – Mechanical
Volume -IIC Balance of Plant (BOP) Facilities
Section 01.00 Water Supply System
Section 02.00 Air conditioning & Ventilation System
Section 03.00 Elevators, Cranes & Hoists
Section 04.00 Fire Protection System
Section 05.00 Piping, Valves & Fittings
Section 06.00 Thermal Insulation, Lagging, Cladding
Section 07.00 Compressed Air System
Volumes Title
Volume - III Instrumentation & Control System
Volume -IV Electrical System
Volume -V Civil, Architectural & Structural Works
Volume -VA Civil Works.
Volume - VB Architectural Works
Volume - VC Structural Works
Volume - VI Mandatory Spares and Tools & Tackles
Volume - VII Tender Drawings
01.00 PREAMBLE
01.01 M/s Tamil Nadu Generation and Distribution Corporation Limited intends
to install suitable Flue Gas Desulphurisation Plant (FGD) in the existing 4
X 210 MW Mettur Thermal Power Station-I at Mettur, in order to adhere
to MoEF&CC latest Notification. This Tender Specification is meant for
inviting bids from prospective FGD plant suppliers for the scope of work
given in the Tender Specification.
Volumes Title
Volume – I Commercial
Volume – II Technical
Volume - IIA General Technical Specification
Section 01.00 Preamble
Section 02.00 Intent of Specification
Section 03.00 Project Information
Section 04.00 Special Instructions to Bidder
Section 05.00 Scope of Work, Supply & Services
Section 06.00 Quality Assurance System / Requirement
Section 07.00 Painting
Section 08.00 Finalization of Sub-vendors / Sub-contractors
Section 09.00 Performance Guarantees
Section 10.00 Terminal Points & Exclusion
Section 11.00 Layout and Maintenance Requirement
Section 12.00 Drawings / Documents to be submitted along with Bid /
Offer and after award of contract
Volume - IIB Technical Specification
Section 01.00 Flue Gas Desulphurization System (Semi Dry)
Section 02.00 Technical Data Sheets – Mechanical
Volume -IIC Balance of Plant (BOP) Facilities
Volumes Title
Section 01.00 Water Supply System
Section 02.00 Air Conditioning & Ventilation System
Section 03.00 Elevators, Cranes & Hoists
Section 04.00 Fire Protection System
Section 05.00 Piping, Valves & Fittings
Section 06.00 Thermal Insulation, Lagging, Cladding
Section 07.00 Compressed Air System
Volume - III Instrumentation & Control System
Volume -IV Electrical System
Volume -V Civil, Architectural & Structural Works
Volume -VA Civil Works.
Volume - VB Architectural Works
Volume - VC Structural Works
Volume - VI Mandatory Spares and Tools & Tackles
Volume - VII Tender Drawings
a. The drawings enclosed with the Tender Document form part of the Tender and
shall supplement the requirements specified herein. These drawings shall be
read in conjunction with the texts of the specifications.
b. The Tender drawings are for “Tender Purpose Only” and indicative for
Purchaser’s basic minimum outline requirements to enable the Bidder to make
a suitable offer.
c. Bidder shall note that only certain terminal point details are depicted in the
tender drawings. For complete details of terminal points and scope of work,
relevant write up of Tender document shall also be referred. The terminal
points and scope details shown in the drawings are complementary and
supplementary to that available in the relevant portion of the write up of
Tender Document.
INTENT OF SPECIFICATION
02.01 This Specification is for installation of Flue gas desulphurization plant (FGD) at
TANGEDCO Limited’s existing 4X210 MW Mettur Thermal Power Station-I, located
at Mettur.
02.03 The entire scope shall be on EPC turnkey basis and also on single point responsibility
basis.
The scope shall also cover the following activities and services in respect of all the
equipment and works specified in various sections of this specification:
f) Packing and transportation from the manufacturer’s works to the site including
customs clearance, port charges, if any;
equipment at the site, movement from storage area to interim/ final foundation
location / Shop.
k) Supply of any other equipment including special tools and tackles, commissioning
spares and services required for satisfactory completion of the project and
operation and maintenance of the same;
p) All items and equipment though not specifically mentioned in the specification,
but needed to complete the system to meet the intent of the specification shall be
deemed to be included in the scope of the bidder.
It is not the intent to completely specify all details of design and construction, but only
to lay down broad sizing and quality criteria for the major equipment and systems and it
is expected that the equipments shall conform in all respects to high standards of
engineering, design and workmanship and shall be capable of performing in continuous
commercial operation up to the bidder’s guarantee in a specified manner acceptable to
the purchaser.
The bidder is required to carefully examine and understand the specifications and seek
clarifications, if required, to ensure that he has understood the specifications as intended
by the purchaser. In the absence of any specific clarifications made by the Bidder during
bidding stage, the interpretation of Purchaser shall be final. The bidder’s offer should
not carry any sections like clarifications, interpretations and/or assumptions. All such
points are required to be clarified during bidding stage.
In the event of conflict between the requirements of any two clauses of this
specification/document or requirements of different codes/standards, the more stringent
requirement will govern, unless confirmed otherwise by the Purchaser/Consultant in
writing, in reply to a written request from the bidder for such clarifications.
In case all the above requirements are not complied with, the bid may be considered as
incomplete and liable to be treated as non-responsive. Whenever a material or article is
specified or described by the name of a particular brand, manufacturer or vendor, the
specific items mentioned shall be understood as establishing type, function and quality
desired. Other manufacturers’ products may be considered provided sufficient
information is furnished so as to enable the Purchaser to determine without the need for
any additional clarification/data, that the products proposed are proven and equivalent
or superior to those named.
03.01 This Tender Specification is for installation of Flue gas desulphurization plant (FGD) in
TANGEDCO Limited’s existing 4X210 MW Mettur Thermal Power Station-I.
03.02.01 All the facilities of FGD system as covered under this Tender Specification shall be executed as
a single EPC Turnkey Contract on Single Point Responsibility Basis. The power plant site (i.e.
4X210 MW MTPS-I) is located at Mettur.
Calm (Min.)
xix) Seismicity Zone III Moderate damage risk zone- IS:
1893 -2002
xx) Languages spoken in the English, Tamil
region
xxi) Tropicalisation All equipment supplied against this
specification shall be given tropical and
fungicidal treatment in view of climatic
conditions prevailing at site.
The plants and equipments covered under this Tender Specification shall consist of the
following:
Four (4) nos. FGD plant for 4x210 MW Thermal Power Station.
Layout of Plant & Equipment shall be such that it provides a complete integrated system for
smooth, efficient and safe operation. The layout scheme, orientation of various facilities etc. are
shown in the layout drawings enclosed with the Tender Specification.
2. For the design of various components/ equipment of lime receiving, handling, feeding,
conveying, storage etc. the bulk density of lime shall be considered as 880 kg/m3 for
volumetric computations and 1920 kg/m3 for torque, drive & structural load calculation.
3. For by-product, the bulk density shall be taken as 800 kg/m3 for volumetric
computation and 1600 kg/m3 for torque, drive & structural load requirement
03.07 The flue gas analysis at FGD inlet (ID fan outlet) shall be considered as below:
03.09 Light Diesel Oil (LDO) Characteristics (As per IS 15770 – 2008)
03.10 Heavy Fuel Oil (HFO) Specification- used for startup/low load only
04.01 General
i. Under this Tender Specification, installation of FGD plants has been envisaged at
4X210 MW Mettur Thermal Power Station-I (MTPS-I) of TANGEDCO.
ii. The Bidder shall base the equipment design on the information given in this
specification. The equipment shall be complete in all respects. Any item which is not
specifically mentioned herein but found essential for safe and efficient operation and
maintenance and satisfactory performance of the system shall be deemed to have been
included in the scope of the Bidder. It shall be presumed that the Bidder has studied the
site, all the drawings, tender documents and is fully aware of the scope of work
involved and the site conditions prevailing. Bidders are strongly advised to visit the site
and thoroughly get acquainted with the site features before submitting their offer.
iii. The Bidder shall include Mandatory Spares, Tools and Tackles, and Erection &
Commissioning spares. No erection and commissioning activity shall be stranded
because of non availability of commissioning spares. All these spares shall be new and
unused. The mandatory spares to be included have been listed in Volume -VI of the
specification.
iv. The Bidder shall include one set of new and unused Tools & Tackles as specified in
Volume -VI of the specification.
v. For Initial Fill, oil, Lubricants and consumables (including supply of reagents and other
chemicals if any), Bidder shall refer Vol. IB of the Tender Specification.
vi. A stainless steel name plate with letters engraved in English language shall be provided
for all the equipment. The name plate shall indicate make, identification, number,
capacity, rating and weight of the equipment. The name plate shall be fitted at a
prominent place on the body of each equipment with the help of S.S. screws.
vii. All the instruments shall be calibrated only in metric units. English shall be the
language of all communications.
viii. Any additional work / equipment and materials which may not have been specially
mentioned in this specification but are required to make the plant complete in every
respect in accordance with technical specification and are necessary for safe & efficient
operation & maintenance and guaranteed performance of the plant shall be deemed to
have been included under the scope of this specification and shall be provided by the
successful Bidder within the contract price.
ix. Any loss of plant and equipment due to imprudence, negligence and / or inequitable
treatment and handling, shall be replaced by the Bidder at his own cost.
x. The Bidder shall not off load the contract or part thereof to any sub vendor / sub-Bidder
without the written permission of the Purchaser, subject to the “stipulations related to
selection / finalization of sub vendors / sub contractors” stipulated elsewhere in the
Tender Specification. In the event of subletting of any part of the work with due
permission by the Purchaser, such permission shall not absolve the Bidder from any of
his obligations and liabilities under the contract.
xi. It shall be the responsibility of the Bidder to obtain the necessary approval of the
concerned inspecting Authority / Chief Inspector of Boiler and Chief Controller of
Explosives, approval of Electrical inspector and all other statutory inspecting authorities
for the design and design calculations, manufacturing and erection procedure as called
for under the above regulations and any other applicable statutes. Obtaining stability
certificate in case of buildings & structure, from Director of Factories, Govt. of Tamil
Nadu shall also be in the scope of the Bidder. Bidder shall have a certified engineer who
is authorized to authenticate the documents to be submitted to the Director of Factories,
Govt. of Tamil Nadu.
xii. The Bidder shall furnish all the drawings, documents, load data and other information /
data like fault diagnosis, operation, maintenance, erection manuals etc, general details
and layout drawings, design calculations and equipment specification of plant and
equipment, together with “as built drawings” for all civil, structural, mechanical,
electrical and control & instrumentation portion.
xiii. All civil, architectural and structural works shall be carried out by the Bidder and the
related foundation drawings, arrangement drawings with design calculations shall be
submitted to Purchaser/consultant for review/approval.
xiv. It shall be Bidder’s responsibility to provide necessary and adequate arrangements for
safe disposal of effluent generated from the plant and equipment. The method / scheme
of disposal shall meet statutory regulation and shall also be acceptable to the Purchaser.
All facilities required for treatment of such effluents to make them suitable for disposal
shall be provided. Required neutralization / treatment system, pumps with drives, pipes
with valves and accessories, supports etc., as may be required, shall be included under
Bidder’s scope.
xv. Bidder in his offer shall clearly indicate the quantity, quality and frequency of
generation of effluent from the plant and equipment.
In addition to the codes and standards specifically mentioned in the relevant technical
specifications for the equipment / plant / system, all equipment parts, systems and works
covered under this specification shall comply with all currently applicable statutory
regulations and safety codes of the Republic of India as well as of the locality where
they will be installed, including the following:
All equipments, systems and works covered under this specification shall comply, in all
respect, with requirements of applicable latest statutes and that of latest editions of
codes and standards. Latest regulations and safety & environmental requirements as
applicable in India / state of installation shall also be complied with.
Unless covered otherwise in the specifications, the latest editions (as applicable as on
date of bid opening), of the codes and standards given below shall also apply:
Other International/ National standards such as DIN, JIS, VDI, EN, BS, GOST etc. shall
also be accepted for only material codes and manufacturing standards, subject to the
Employer's approval, for which the Bidder shall furnish, adequate information to justify
that these standards are equivalent or superior to the standards mentioned above. In all
such cases the Bidder shall furnish specifically the variations and deviations from the
standards mentioned elsewhere in the specification together with the complete word to
word translation of the standard that is normally not published in English.
In the event of any conflict between the codes and standards referred to in the above
clauses and the requirement of this specification, the requirement Technical
Specification shall govern.
If the equipment supplied does not conform to the above codes and standards, but is
manufactured to the Bidder's own standard, developed as a result of his experience, is
also acceptable provided the same is found to be superior to the above mentioned codes
and standards. The Bidder shall identify such plant and equipment and shall also present
sufficient data to the Purchaser / Consultant to support his design and to establish the
superiority. The design may be accepted by Purchaser / his Consultant only if the
Purchaser / his consultant is satisfied that sufficient experience exists with the design
proposed.
Design not meeting the stipulations of the codes and standards will not be acceptable.
ii. Normally deviations from the specification / assumptions are not acceptable. However,
if it becomes absolutely necessary for the Bidder to take deviation, the Bidder shall
mention clearly in the offer / bid, the deviation taken by him from the specification and
statement of non-conformity in detail with reasons for each such deviation. The
statements shall also show that the quality of the equipment standards shall be entirely
suitable for the purpose intended and substitute for the specified ones. Such deviations
shall be discussed during the techno commercial discussions with the Bidder. Such
points which are discussed and mutually agreed upon during techno commercial
discussions only shall be included in the Contract.
iii. In case the Bidder does not submit any list of deviations / assumptions, all requirement
and provisions of the specification shall be automatically deemed to have been agreed
and complied by the Bidder. To accept or reject, in full or part thereof, any of the
deviations shall be under the privilege of the Purchaser / his Consultant without
assigning any reason thereby. All the technical deviations taken by the Bidder, if any,
shall be indicated at only one place as per the format given in commercial volume of the
Tender Specification. Deviations, indicated at any other place shall not be considered /
entertained.
iv. While in general the design, manufacture and supply of the plant and equipment shall
comply with the requirements and conditions stipulated in this specification, any
assumption made, to arrive at different solution / calculation for working out details as
indicated in the offer, shall be clearly spelt out and brought out in the bid / offer by the
Bidder.
v. Any contradiction between the provisions called for in the technical specification and
other documents enclosed with the tender enquiry shall be a matter of clarification to be
sought for by the Bidder from the Purchaser / his Consultant. However, on any
contradiction / difference of opinion / ambiguity arising during the course of Bid due to
any lack of clarity on such account and not settled during the tender stage, the
interpretation of the Purchaser / his consultant shall be final and binding on the Bidder.
vi. In the event of conflict between requirements of any two clauses of the
specification documents, the more stringent requirements shall apply, unless otherwise
confirmed by the Purchaser in writing before the award of this contract, based on a
written request from the Bidder for such clarification.
Equipment furnished shall be new, unused and complete in every respect with all
mountings, fittings, fixtures and standard accessories normally provided with such
equipments and/ or needed for erection, commissioning and safe operation of the
equipments as required by applicable codes though they may not have been specifically
detailed in the respective specifications, unless included in the list of exclusions. All
similar standard components/ parts of similar standard equipments provided shall be
During execution of the contract, successful Bidder will furnish the engineering data /
drawings / calculations, etc. in accordance with the schedule of information agreed
between Purchaser and the successful Bidder. Review of these data by the Purchaser’s
Engineer / Consultant shall cover only general conformance of the data to the
specifications and documents interfaces with the equipments provided under
specifications, external connections and of the dimensions which might affect plant
layout.
This review by the Purchaser’s Engineer / Consultant may not indicate a thorough
review of all dimensions, quantities and details of the equipments, materials, any
devices or items indicative of the accuracy of the information submitted. This review
and/ or approval by the Engineer shall not be construed by the Contractor, as limiting
any of his responsibilities and liabilities for mistakes and deviations from the
requirements specified under these specifications and documents.
The Bidder shall submit Time Bar chart indicating completion date of major activities
such as submission of design data / calculations and drawings for approval,
manufacturing of components / units, supply, inspection, erection, testing and
commissioning etc. without which the Tender shall not be considered. Time Bar Chart
furnished shall afterwards form part of the contract and cannot be altered arbitrarily
except Force Majeure conditions as may be agreed with the Purchaser.
The successful Bidder shall submit monthly progress report to the Purchaser right from
the commencement of the work till finishing and handing over of the work. The report
shall cover all the major activities and shall be a subject of discussion with the
Purchaser/ Consultant, for timely completion of the project.
On commencement of site work, the successful Bidder shall submit to the Purchaser, a
weekly site “Progress Report”. This report shall be discussed at the regular site
meetings between Bidder and Purchaser as an agreed accurate record of the weekly
progress.
The plant and equipment shall be designed to have maximum reliability with ease of
operation and maintenance as primary consideration. The plant offered shall be from a
family having basic design at par with other plants which have already been supplied
and have operated efficiently and reliably elsewhere under similar climatic and
operating conditions.
All moving parts of equipment, which can conceivably cause injury to the operator and
otherwise authorized personnel within the vicinity of working area shall be suitably
guarded and warning displays shall be put at prominent places.
The Bidder shall clearly indicate and identify the plans and procedures, which shall be
followed in the design, manufacture and installation of plant and equipment to control
and assure to the Purchaser of the desired quality.
The plant and equipment shall be subjected to inspection and witnessing of shop tests
by the Purchaser / Consultant or the agency mutually agreed between Purchaser and the
Bidder. The successful Bidder shall inform the Purchaser/his Consultant sufficiently
well in advance of the date when the plant and equipment shall be made available for
inspection and testing. The Purchaser and / or his Consultant shall be given full access
to the tests and testing premises and can inspect the factories and offices of the Bidder
or sub-vendor, if so required. After inspection and testing, all certificates /documents as
required by the Purchaser / Consultant shall be submitted for approval to the purchaser
before clearance for dispatch of equipment can be given.
For plant and equipment for which tests at works may not have been witnessed by
Purchaser / Consultant, the tests and quality certificates duly signed by appropriate
authority acceptable to Purchaser / Consultant shall be submitted to the Purchaser /
Consultant for approval within 6 weeks in advance of the dispatch.
Inspection by the Purchaser or his representative shall not relieve the Bidder of his
liability for rectifying any defects which may subsequently appear or be detected during
or after erection and during guarantee test. After rectification, the testing of equipment
shall be repeated to the satisfaction of the Purchaser / Consultant.
In order to enable the Purchaser / Consultant to properly evaluate the tenders, the
drawings / documents / technical particulars as indicated in respective chapters of this
specification shall be submitted by the Bidder along with the bid / offer.
The Bidder shall furnish the details of the drawings for Purchaser’s/ his Consultant’s
approval and/or for use, to detail out the other connected systems / facilities not forming
part of this tender, within the period of one month of placement of order or as mutually
agreed between the Purchaser and the Bidder and shall fit in the total implementation
The surface of plant & equipment shall be suitably cleaned and coated with anti-rust
primer to protect against corrosion and damage during transit and transportation to the
site.
Painting shall be done as per details indicated in the relevant Chapter and as per the
approved painting schedule.
All equipment, pipes, valves, instruments, etc. shall be suitably packed for protection
against mechanical damages and climatic conditions during transit and storage. Packing
and weather proofing shall be subject to approval of the Purchaser / Consultant. This
approval shall be general and may not be required every time for an article to be
dispatched. However, the Purchaser reserves the right to examine the packing for any
particular consignment at supplier’s/ manufacturer’s works before dispatch.
The Bidder shall be entirely responsible for the insurance, shipment, handling and
transportation of all plant & equipment, construction tools, labourers and materials
including unloading at destination, transportation to site, off-loading, storing and
protection at site till erection.
The equipment shall not be dispatched by the Bidder from the place of manufacture to
the site until the dispatch instructions are issued by the Purchaser.
The plant and equipment supplied shall be properly stored at site, handled, erected,
tested and commissioned individually as well as for integrated operation by the
successful Bidder.
During site testing and commissioning, Bidder shall follow approved safety clearance
system. The details of these systems are to be approved by the Purchaser / Consultant.
The performance guarantee parameters of the plant shall be demonstrated by the Bidder
within the agreed time frame.
All the plant and equipment supplied shall be guaranteed for quality workmanship and
compliance with the specified requirements for integrated performance to deliver rated
outputs. Non-compliance and non-performance shall be subjected to correction or L.D. /
penalty to be paid by the Bidder to the Purchaser as specified elsewhere in the Tender
Specification.
The Bidder shall submit all final drawings, documents, manuals for Purchaser’s use and
for reference / record required during course of operation and maintenance of the plant.
Numbers of copies and their form (hard copy, electronic form, reproducible) to be
submitted is indicated elsewhere in the Tender Specification. The details of the
documents, drawings, manual etc. to be furnished by the Bidder are described elsewhere
in the Tender specification.
05.00 SCOPE OF WORK, SUPPLY & SERVICES FOR SEMI DRY BASED FLUE
GAS DESULPHURISATION (FGD) SYSTEM
05.01 General
Vol. – IIB, Section 05.00 SCOPE OF WORK, SUPPLY & SERVICES Page 1 of 12
© 2020 MECON Limited. All rights reserved.
TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
• Complete C&I work including field instruments, analysers, PLC based control
system along with it’s RTU’s ( Remote Terminal Unit)( if required), UPS
system, Instrumentation Cable (FRLS type & Armoured) & Fibre Optic
cables( as required ), cabling, branch cable trays up to the plant main cable tray,
hardware required (like networking equipment/ cabinet etc) for
interfacing with local and remote-control systems including plant DCS, and
defined power feed terminal point are included in the scope of work.
FGD system needs an independent, reliable, emergency A.C. source when all other
A.C. power supplies fail (i.e. Plant blackout condition). The bidder shall identify
the emergency load requirement for the FGD plant.
Vol. – IIB, Section 05.00 SCOPE OF WORK, SUPPLY & SERVICES Page 2 of 12
© 2020 MECON Limited. All rights reserved.
TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
Bidder shall offer either Circulating Dry Scrubber (CDS) type semi dry FGD
system or Spray Dryer Absorber (SDA) type semi dry FGD system for each unit
of Mettur Thermal Power Plant-I (MTPS-I 4X210 MW).
Semi Dry FGD shall consist of a main Reactor section, a pulse jet fabric filter
(PJFF) baghouse, by-product recycle system, booster fans and associated ducts,
dampers, lime storage and handling system and by-product storage and handling
system.
Bidder shall only offer proven system in successful operation in previous
installations as defined under qualification criteria.
The FGD system shall be generally in line with the Tender scheme / drawing
enclosed along with this tender document.
The CDS system shall be designed to utilizes a semi-dry reactor to offer the
proper chemistry and in-situ conditions for simultaneous and effective
absorption of sulphur dioxide, acid gases and associated heavy metals. Hydrated
lime powder and water injection system into the reactor vessel shall be designed
to cater maximum contact and reaction with the untreated flue gas. To optimize
reagent utilization, a portion of the dry reaction solid products may be collected
downstream of the system and recycled back to the reactor
Four (04) no. CDS reactor, one for each unit shall be provided for 4x210 MW
Mettur thermal power station (MTPS), Each capable of treating the total flue gas
flow. If modular CDS system is offered, one off- line module shall be provided.
The offered CDS reactor(s) shall be capable of meeting simultaneously all
guarantee parameters from minimum to maximum boiler load operation.
The design shall include controlling dust concentration in the influent flue gas as
Vol. – IIB, Section 05.00 SCOPE OF WORK, SUPPLY & SERVICES Page 3 of 12
© 2020 MECON Limited. All rights reserved.
TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
co benefit.
Low leak guillotine isolation dampers at inlet and outlet of CDS vessel shall be
provided. Low leak is defined as Maximum 5%.
Also, bidder to provide thermal insulation for all supplied equipment, ductwork,
and piping systems per the design conditions.
In case the bidder is offering SDA system then bidder shall provide the
following, as a minimum:
a) Each unit shall have one (01) no of SDA vessel complete with gas distribution
devices; rotary atomizers with drives and self-contained lubrication system;
conical hoppers at the outlets, atomizer monorail and radio-controlled hoist
system, dedicated hoists and rails for SDA vessel and access doors shall be
provided for each unit.
b) Bidder to provide N+1 configuration of rotary atomizers with drives and self-
contained lubrication system, where N stands for no of atomizers in operation to
meet the guaranteed performance.
c) Low leak guillotine isolation dampers at inlet and outlet of SDA vessel shall be
provided. Low leak is defined as Maximum 5%.
d) Thermal insulation for all supplied equipment, ductwork, and piping systems per
the design conditions.
b) Bidder to offer 2X50% Booster fans for each unit. The aggregate capacity of
the booster fan(s) shall match with that of the ID Fans at the guarantee and
design points as well as over the entire operating range. Margins as specified
under design criteria shall be adopted. The fans shall have blade pitch type or
inlet guide vane control system to vary the air flow, depending on the type of
fan.
Vol. – IIB, Section 05.00 SCOPE OF WORK, SUPPLY & SERVICES Page 4 of 12
© 2020 MECON Limited. All rights reserved.
TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
c) Each fan shall be of Axial or centrifugal type with blade pitch control, with
coupling and drive motor. Each Booster Fan shall be provided with bearing
lubrication and hydraulic blade pitch control unit(s), each system consisting of:
(i) 2x100% oil pumps with motor, coupling and coupling guard.
(ii) 2x100% oil coolers.
(iii) 2x100% filters, differential pressure switches, etc.
(iv) 1x100% oil storage tank.
(v) Instrumentation, vibration monitoring, inter connected piping, valves and
fittings including pressure relief valves and non-return valves.
(vi) Electrical actuator with accessories etc. bearing temperature at motor and
fan end along with motor winding temperature monitoring,
(vii) Alternatively, a forced oil lubrication system (consisting of i to vi
above) common for bearing lubrication and for servo motor operation for
each Booster Fan will also be acceptable.
d) At least two (02) nos. of duplex thermocouples or duplex platinum RTDs (100
ohm at 0oC) and one number of temperature indicators shall be provided for
bearing metal temperature measurement, control and monitoring for each fan.
f) Inlet flue gas duct damper at common inlet duct to booster fan
h) Bypass damper at existing common duct before FGD outlet duct connection to
common duct at chimney inlet.
The system shall be sized to store and transfer the required amount of lime to
the lime preparation system, based on the range of operating conditions. Lime
shall be pneumatically conveyed (system provided by bidder) from trucks to
Lime Storage Silos.
a) Two (02) nos. of Lime storage silo shall be designed for 07 days storage
capacity for maximum lime requirement of the all the five units
b) Lime shall be delivered to site primarily by trucks.
c) Pneumatic conveying system for unloading the lime from truck.
d) Pneumatic conveying system shall be provided for unloading the lime from
storage silo to bins in the lime preparation area. To allow operation flexibility,
Vol. – IIB, Section 05.00 SCOPE OF WORK, SUPPLY & SERVICES Page 5 of 12
© 2020 MECON Limited. All rights reserved.
TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
the conveying arrangement shall be such that the Lime conveyed from any one
storage silo can be delivered to either of the bins.
e) Silo vent filters shall be provided to remove collected lime dust
f) Compressed dry air shall be provided to pulse the bags or cartridges.
g) Pressure and vacuum relief devices shall be provided.
h) Complete dust extraction and natural ventilation system shall be provided in
open transfer points or enclosed areas, as required.
i) One (01) no. lime bin shall be provided to aid feeding lime to the hydrator, if
provided shall be for each unit.
j) Access and platforms shall be provided for all instrumentation, valves etc.
By product recycle system for each unit shall include the following equipment,
as a minimum:
a) Fluid troughs for each unit to collect by product from fabric filter bag house.
b) Expansion joints for each unit, as required.
c) Three (3)x 50% (02 Working + 01 stand by) fluidized air blowers for each unit.
d) Rotary Feeder(s) for controlling by-product recirculation for each unit.
The system shall be sized to transfer and store the by-product in the silo.
Suitable arrangement shall be provided at the discharge of silo for unloading in
to truck. The system shall include the following equipments, as a minimum:
a) One (01) no. intermediate byproduct silo to store 1 days generation of by product
for each unit.
b) Pneumatic conveying system to transfer the by-product from bag house hopper
to intermediate silo.
c) Motorised knife gate valve along with telescopic chute (motorized) shall be
provided at each silo discharge.
d) Two (02) no. Main byproduct silo for storing the byproduct of the entire 4 units
and the same shall be placed outside the plant boundary at a specified location
approved by the purchaser.
e) All necessary arrangements shall be made by the contractor for conveying the
byproduct from the main byproduct silo upto the trucks.
Vol. – IIB, Section 05.00 SCOPE OF WORK, SUPPLY & SERVICES Page 6 of 12
© 2020 MECON Limited. All rights reserved.
TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
The fabric filter bag house shall be capable of operating and meeting emission
and performance guarantees with one bag house compartment offline. The
system shall be designed to operate in conjunction with the r eactors, recycle,
and waste handling systems.
Vol. – IIB, Section 05.00 SCOPE OF WORK, SUPPLY & SERVICES Page 7 of 12
© 2020 MECON Limited. All rights reserved.
TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
b) The bidder shall submit with the offer, comprehensive information on how the
mass balance, spray nozzle cone angle, spray nozzle arrangement, lime
consumption etc. as applicable for the proposed design have been arrived at. The
bidder shall also submit along with the offer, a detailed write up on the proposed
design features and control philosophy at varying loads to achieve the desired
level/ efficiency of SO2 and PM removal.
c) In general, the material selection is the bidder’s responsibility, but the quality of
material for pressure vessels, piping, etc., however, must meet the requirements of
the relevant IS/ASME standards. The bidder shall specify in his bid the material
quality and the standards applied to each equipment, piping system, etc.
Vol. – IIB, Section 05.00 SCOPE OF WORK, SUPPLY & SERVICES Page 8 of 12
© 2020 MECON Limited. All rights reserved.
TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
g) The FGD plant shall be able to handle the load imposed on the FGD plant by the
boiler, including rate of load changes, minimum load and the anticipated daily and
annual load schedules. Furthermore, the FGD plant shall be able to be put in
operation, while the boiler is in operation at any load, without any disturbance in
the operation of the Unit.
h) In case of a failure of an item of equipment (e.g. pumps, etc.) the stand-by unit
has to be activated and put into service automatically without delay and without
interruption of the plant operation and audio-visual alarm to such effect shall
be provided in the control room.
i) In case of failure of the boiler and ancillary equipment, the associated FGD plant
shall be brought automatically to the off-load operation without restriction by the
current loading.
k) The dry FGD system offered by the bidder shall be in line with the specified
scheme of FGD process. However, proven variations are permissible for
optimization of the process based on bidder’s design and experience. These
variations shall, however, not change the basic essence or configuration of the
process specified. Specific advantages of such variations shall be indicated by the
bidder in his bid. All modifications/variations proposed from the process specified
shall be subject to approval from the Owner. Description of the process which
has been offered by the Bidder must be submitted in detail indicating clearly the
function of each equipment.
l) The materials of construction for all exposed metal/ concrete surfaces shall be so
chosen as to withstand the prevailing environment at plant site. Also suitable
weather protection shall be provided to all exposed surfaces as required. The
equipment and the auxiliaries shall be designed for maximum reliability and
availability; operability and maintainability. The bidder shall specifically state the
design features incorporated to achieve the high degree of reliability and
availability.
Vol. – IIB, Section 05.00 SCOPE OF WORK, SUPPLY & SERVICES Page 9 of 12
© 2020 MECON Limited. All rights reserved.
TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
n) All stand-by auxiliaries shall be designed for auto start up, on failure of
running auxiliaries with minimum time delay and without runback on unit load.
o) The plant and its units shall be designed to operate with all the specified margins
for continuous operation without any limitations under any of the conditions
indicated in the Technical Specification.
p) All materials used for the construction of the equipment shall be new and shall
be in accordance with the requirements of this specification. Materials utilised for
various components shall be those which have established themselves for use in
such applications. It would be the responsibility of the bidder to furnish the
relevant information in this regard, as required, at the time of detailed
engineering.
q) The process proposed must be free of any danger for personnel handling the
equipment, for related operations and for the surroundings. This requirement
applies for normal operation as well as for starting up & shut down.
Vol. – IIB, Section 05.00 SCOPE OF WORK, SUPPLY & SERVICES Page 10 of 12
© 2020 MECON Limited. All rights reserved.
TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
“fail safe” i.e. they must be triggered in the case of an electric voltage or air
pressure outage.
t) Roller bearings provided on pumps, fans, air compressors, agitators and other
equipment shall have a life of at least 10 years with maximum loading conditions.
Journal bearings provided should have operational life equal to the life of the
equipment.
u) All heavy parts of the plant must be provided with some convenient arrangement
for aligning and for handling during erection and overhaul. Any item of plant
required to be stripped or lifted during period of maintenance and weighing one
tons or more shall be marked with its approximate weight. All equipment shall be
designed to run satisfactorily without any undue noise and vibrations.
Corresponding parts throughout shall be made to gauge and shall be
interchangeable wherever possible. No welding, filling or plugging of defective
parts shall be allowed without the permission in writing of the Owner.
v) The structure of the FGD plant shall be adequately designed taking into
account the local seismic factors and wind conditions prevailing at site. A project
design manual indicating design data and detailed design criteria for civil and
structure steel work shall be submitted for the approval of the consultant/Owner.
In case of coastal climatic conditions, the special measures adopted to protect
reinforced concrete and structural steel shall be included in the design criteria.
05.05 Electrical
Refer Vol. IV for electrical scope of work
05.06 Tests
The scope of the bidder includes all shop tests, type tests, site tests, routine tests
etc., fulfilment of compete quality assurance and inspection requirements and
related activities for all the equipment and systems covered under the scope of
work of bidder as per the stipulations of technical specifications.
The bidder shall include a complete new set of all special tools and tackles,
mandatory spares, commissioning spares of reputed make and model which are
required for erection, ease in maintenance to have a minimum down time,
Vol. – IIB, Section 05.00 SCOPE OF WORK, SUPPLY & SERVICES Page 11 of 12
© 2020 MECON Limited. All rights reserved.
TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
testing and calibration of all the equipment and systems in his scope of supply
under this specification for the above-mentioned items.
05.09 Civil
Refer Vol. V for Civil, Architectural & Structural electrical scope of work.
Vol. – IIB, Section 05.00 SCOPE OF WORK, SUPPLY & SERVICES Page 12 of 12
© 2020 MECON Limited. All rights reserved.
SECTION 06.00
QUALITY ASSURANCE
SYSTEM
06.01 General
Inspection & testing of plant & equipment shall be witnessed by Purchaser / his
representative / Purchaser as per approved QAP at the works of successful bidder
during manufacturing and / or on final product to ensure conformity of the same with
the acceptable criteria of technical specifications, approved drawings, manufacturing
drawings and applicable national / international standards.
The successful bidder must recognise the importance of quality and follow defined
quality programme in all stages of. manufacturing and quality control activities of the
product. Contractor must define and implement the tasks and controls that will provide
needed assurance, in case manufacturing of product is sub-contracted either partly or
fully and/or for the procured components of the product. All bought-out equipment or
component shall be procured from preferred vendor list of concerned project.
Purchaser / his representative / Purchaser reserve the right to verify the quality
programme of bidder & its vendors/sub- vendors to assure the effectiveness of the
programme to meet the intended and specified quality of the product.
06.03.01 The successful bidder shall furnish Quality Assurance Plan (QAP) for all equipment
in respective packages after finalization of billing schedule / equipment
identification number for Purchaser / his representative’s approval at least one
month prior to start of manufacturing in accordance with clause 06.03.02 and
06.03.03 of this chapter.
06.03.02 QAP shall be prepared & furnished separately by Contractor in Form Nos.
11.20(DQM)F-09,10 , 11, Rev 0 (specimen blank enclosed) for structural, mechanical,
electrical, instrumentation and refractory items respectively , including major bought-
out items. QAPs must be submitted in requisite sets as per contract for approval and
shalll be duly stamped and signed by the successful bidder . Also, column no. 4, 5, 6 &
7 of QAP formats are tentative and for reference purpose only. QAP submitted in any
format other than those mentioned above will not be accepted.
06.03.03 The successful bidder shall submit copies of P.O., Sub-P.O., T.S., approved GA
drawings/ data sheets & detailed manufacturing drawings(if asked for) along with
QAP as backup reference materials for scrutiny & final approval of QAP by Purchaser
/ his representative. All billable items as per approved billing schedule of same
category (i.e mechanical, electrical, structural, refractory etc) shall preferably be
submitted in a single lot, serial wise, to avoid unnecessary delay in the process of QAP
Approval.
06.03.04 Inspection and test requirements shall be decided with due consideration of factors like
safety, duty cycle, operating conditions, equipment life, environmental conditions,
place of installation and statutory regulations, as applicable, for a particular equipment.
Any, additional type or special tests or routine tests if found necessary to establish the
intended quality after detailed engineering, then same have to be incorporated in the
QAP without any commercial implication.
06.03.05 QAPs shall be prepared by the successful bidder in consultation with their
Sub-contractors / Manufacturers to avoid any complicacy later .
06.03.06 Soft copies may be forwarded in advance for intimation. However, hard copies shall be
submitted in requisite sets to enable Client to forward comments if any.
06.03.07 Approval of QAP does not gives approval of make. Make shall be as per contract.
06.04.01 All the measuring equipment used for inspection & testing shall be of appropriate
accuracy class and shall have valid calibration certificate with traceability to national
standards of NPL / NABL accredited laboratories with unbroken chains of
comparison. Same calibration certificates shall be submitted to Purchaser / his
representative/ Purchaser for review prior to inspection.
06.04.02 Calibration certificate shall also indicate reference no. of calibration standards
calibrated by NPL / NABL accredited laboratories and copies of such calibration
certificates of calibration standards shall be included in the compiled dossiers of
inspection/test results.
06.04.03 In case valid calibration certificates are not available, inspection will not be carried
out using uncalibrated instruments and cost of revisit in that eventuality shall be
borne by the successful bidder.
06.05.01 For each of the items being manufactured as per approved QAP , following test
certificates and documents, as applicable for each of the equipment, in requisite copies
including original, duly endorsed by the Manufacturer and successful bidder with
appropriate linkage to project, purchase order and acceptance criteria etc shall be
submitted to Purchaser / his representative/ Purchaser.
i) Raw materials identification & physical and chemical test certificates for all materials
used in manufacture of the equipment.
iii) Details of stage-wise inspection & rectification records for fabricated items, castings,
forgings and machined articles.
vii) Non-Destructive Test reports as per respective code carried out by NABL
accredited laboratory.
xii) Routine / Type / Calibration /Acceptance / Special tests ( Type Tests etc) certificates
for electrical/ power electronics/ automation/ instrumentation items as identified in
QAP. Furnishing valid type test certificate for similar design of above items is
mandatory until unless exemption is granted specifically in technical specification for
any item. In case, type test certificate of similar design is not available, successful
bidder shall organize to carry out such tests at his cost without affecting the project
schedule.
xiv) Certificates from competent authority for the items coming under statutory regulations
(IBR/ FM/ UL/ CMRI/ NEPA/ Weights & Measures etc.)
06.05.02 Where physical and chemical test certificates of raw material are not available, the
successful bidder /Sub-contractor shall arrange to have specimens and test samples
of the materials, tested in NABL accredited laboratory at his cost and submit the
copies of test results in requisite numbers to Purchaser / his representative/Purchaser
for review. Number of test samples against each heat/cast/lot or batch of materials, as
applicable shall be as per relevant Indian or International Standards. This is
admissible only if specific makes are not indicated in the contract.
06.06.01 Inspection and tests shall be carried out by Contractor and Manufacturer in accordance
with approved drawings/datasheet/material specification/T.S/P.O., relevant standards
(BIS/ASME/IEC/DIN/API etc.) and approved QAP. Records shall be maintained for
each inspection & test carried out and signed documents shall be submitted to
Purchaser/Purchaser / his representative for verification.
06.06.02 The successful bidder shall carry out their internal inspection & obtain clearance from
statutory bodies e.g. IBR, CCE, TAC, Weights & Measures, safety (NEPA/ UL/ FM
etc.), IE rules, CMRI etc. prior to offering any equipment for Purchaser/Purchaser /
his representative's inspection in accordance with approved QAP.
06.06.03 The successful bidder/ Manufacturer shall identify all the inspected
equipment/component/raw materials & shall maintain the record of status of inspection
viz. inspected & found acceptable, require rectification/rework, rejected etc.
06.06.04 The successful bidder shall establish and maintain procedures to ensure that the
product that does not conform to specified requirements, is prevented from inadvertent
use or installation. The description of non-conformity that has been accepted
subsequently by Purchaser / his representative/ Purchaser by concession and/or of
repairs, shall be recorded.
06.06.05 Where facilities for testing does not exist in the successful bidder / Sub-contractor's
laboratories or in case of any dispute, samples and test pieces shall be drawn by the
successful bidder /Sub-contractor in presence of Purchaser / his representative /
Purchaser and sealed sample shall be sent to any NABL accredited laboratory for
necessary tests at former’s own cost.
06.06.06 The Purchaser / his representative / Purchaser shall have the right to be present and
witness all tests being carried out by the successful bidder / Sub- contractor at their
own laboratory or approved laboratories. Also, the Inspection Agency shall reserve the
right to call for confirmatory test on samples, at his discretion.
Repaired and reworked product shall be offered for re- inspection to Purchaser / his
representative/ Purchaser along-with records of corrective action taken.
Successful bidder shall submit the schedule for manufacturing and inspection
indicating equipment / components, sub- assembly/ assembly, date of approval of
drawings / data sheets, address of manufacturer with contact person and scheduled date
of inspection. Such reports shall be submitted to respective Purchaser / his
representative Inspecting Offices with a copy to Inspection Co- ordinating Office once
in a month. These monthly reports shall state the planning for next three months.
06.08.01 Inspection call shall be given only on readiness of the equipment/ assembly/
sub-assembly & after approval of all relevant drawings and QAP. Client/MECON
shall be given 10 working days notice period to organize inspection for indigenous
items and 30 working days notice period for imported items. In case, equipment/
assembly/ sub-assembly offered for inspection are found not ready, the call shall be
cancelled. All the cost of visit of Client/Purchaser / his representative's engineer shall
have to be borne by the successful bidder . Photographic evidence to support
readiness of material may be required to furnish along with fresh inspection call.
06.08.02 Inspection call shall be raised to Purchaser / his representative through IMS (Inspection
Management System). Soft copy of all documents like test Certificates, Internal
Inspection Reports, P.O., Sub-P.O., T.S., Approved QAP, approved GA drawings/ data
sheets/manufacturing drawings and all other relevant certificates as per approved QAP
shall be attached with inspection call in IMS. All TC’s shall be signed and endorsed by
successful bidder . Inspection calls without above documents shall be treated as
invalid and shall be ignored. Also, the hard copy comprising of all documents along
with signed and stamped inspection call shall be submitted to Purchaser / his
representative/ Client for further processing. Scrutinizing of call documents will be
start only after receipt of hard copies of inspection call.
06.08.03 The successful bidder shall offer substantial quantities of items for inspection
considering economical aspect of inspection with respect to size of order.
06.08.04 On receipt of the Inspection call, pertaining to particular package / equipment / item,
QA & Inspection group of Purchaser / his representative, Ranchi ( Overall co-
ordinating office for Inspection activities ) shall organize inspection visit or will issue
Inspection assignment to other Purchaser / his representative’s office ( based on
nearness to the vendor's manufacturing works / relevant job expertise ) as per approved
QAP.
06.08.05 Inspection waiver shall be processed based on document review and scrutiny as per
approved QAP.
06.08.07 In absence of Approved / Approved as Noted QAP and Drg./ datasheet, Inspection call
shall not be raised. New inspection call shall be raised as regular inspection calls in
accordance with approved QAP.
06.09.01 The successful bidder shall provide all facilities and ensure full and free access of the
Inspection Engineer of Purchaser/Purchaser / his representative to their own or their
Sub-Contractor's premises at any time, during contract period, to facilitate him to carry
out inspection & testing of the product during or after manufacture of the same.
06.09.02 The successful bidder shall delegate a Representative / Co-ordinator to deal with
Purchaser / his representative/ Purchaser on all inspection matters. Representative of
successful bidder shall be present during all inspection at Sub-Contractor's works.
06.09.03 The successful bidder shall comply with instructions of Purchaser / his representative/
Purchaser fully and with promptitude.
06.09.04 The successful bidder shall provide all instruments, tools, necessary testing & other
inspection facilities to Purchaser / his representative / Purchaser free of cost for
carrying out inspection.
06.09.05 The cost of testing welds by ultrasonic, radiographic and dye penetration tests etc. in
the fabrication workshop shall be borne by the successful bidder .These tests need to
be witnessed & approved by ASNT/ISNT Level-II qualified NDT personals
06.09.06 The successful bidder shall ensure that the equipment / assembly / component of the
plant and equipment required to be inspected, are not dismantled or dispatched before
inspection.
06.09.07 The successful bidder shall not offer equipment for inspection in painted condition
unless otherwise agreed in writing by Purchaser / his representative/ Purchaser.
06.09.08 The successful bidder shall ensure that the equipment and materials once rejected by
the Purchaser / his representative/Purchaser, are not re-used in the manufacture of the
plant and equipment. Where parts rejected during inspection have been rectified as per
agreed procedures laid down in advance, such parts shall be segregated for separate
inspection and approval, before being used in the work.
06.10.01 Inspection Memo:- For rejected items/items, which do not conform to Technical
Specification in one or more quality characteristics requiring rectification / rework,
Inspection Memo [Form No.- 11.20(DQM)F-18] shall be issued indicating therein
the details of observation & remarks. All the non-conformities with respect to
specification of the product shall be indicated in the Inspection Memo for further
quality control by successful bidder .
06.10.02 Inspection Certificate:- On satisfactory completion of final inspection & testing, all
accepted plant & equipment shall be stamped suitably and Inspection Certificate[Form
No.11.20(DQM)F-19] shall be issued by the Purchaser / his representative for the
accepted items.
06.10.03 Inspection Waiver Certificate :- MECON shall release Inspection Waiver Certificate
[Form No. 11.20(DQM)F-20] for the items, which are identified as waiver category in
the approved QAP upon verification of all inspection & test reports as indicated in the
QAP.
06.11.01 Inspection & tests carried out by Purchaser / his representative / Purchaser shall not
absolve the responsibility of the successful bidder / Manufacturer to provide
acceptable product as per the terms of contract nor shall it preclude subsequent
rejection.
06.11.02 Purchaser/ Purchaser / his representative reserve the right to inspect any product at any
stage of manufacturing beyond pre-identified stages & hold points of approved QAP.
07.00 PAINTING
07.01 General
This specification covers the materials, tools, facilities and quality requirement for
surface preparation and painting of steel structures, mechanical & electrical
equipments, technological structures, piping, ducts, chutes etc. for FGD & Auxiliary
system for 4 X 210 MW Mettur Thermal Power Plant-I as elaborated in the tender
specification.
This specification will be read in conjunction with other sections / volumes of the
Tender specification where other related project requirements have been indicated.
The term “Painting” referred herein covers rust preventive, preventive and decorative
coating along with surface preparation of the following areas.
07.02 Surfaces made of aluminium, brass, bronze, stainless steel, and other corrosion
resistant alloys are not required to be painted unless specified except for identification
bands or for aesthetic purposes.
07.03 All machined mating surfaces (e.g. flanges) will be properly cleaned, and will be
provided with protective coating before dispatch.
07.04 The complete painting scheme for any item includes the following basic activities:
i) Proper surface preparation
ii) Application of primer coats
iii) Application of intermediate coats and
iv) Application of finish coats
All the above coats will be of quality paint products and of approved make as
stipulated in this specification. The scope of work will also include supply of all paint
07.05 Painting For Mechanical & Electrical And Other Equipment, Mechanical
Structures, Piping, Ducts Etc.
07.05.01 This section covers the painting requirements for the power plant equipment,
structures, piping etc. and any other surface required to be painted
07.05.02 Codes and Standards
Painting of equipment will be carried out as per the specifications indicated below
and will conform to the relevant IS specification for the material and workmanship.
The following Indian Standards may be referred to for carrying out the painting
job:
a) Surface preparation being a pre requisite for any paint application, will be such as to
clean the surface thoroughly of any materials which will be conducive to premature
failure of the paint substrates.
b) All surfaces to be painted will be thoroughly cleaned of all grease, oil, loose mill
scale, dust, rust and any other foreign matter. Mechanical cleaning by power tool and
scrapping with steel wire brushes will be adopted to clear the surfaces. However, in
certain locations where power tool cleaning cannot be carried out, sand scrapping may
be permitted with steel wire brushes and/or abrasive paper. Cleaning with solvents
will be resorted to only in such areas where other methods specified above have not
achieved the desired results. Cleaning with solvents will be adopted only after written
approval of the Purchaser/ consultant.
c) The workmanship will, in general, be in accordance with IS: 1477- 1971. Surface of
all the steel works to be painted will be thoroughly cleaned and degreased in
accordance with IS:1477 (Part-I) by means of mechanical and power tool cleaning or
shot blasting. The cleaning quality will conform to second quality blast cleaning as per
BS-4332 or to SA 2-1/2 of Swedish Standards Institution SIS 055900. Cleaning of
surface will ensure primer coat is rigidly anchored to the virgin metal surface. Primer
paint will be applied not later than 2-3 hours after preparation of surface, unless
otherwise specified.
07.07 The acceptable surface preparation quality/grade are described under each painting
scheme. The procedures covered are solvent cleaning, hand tool cleaning, power tool
cleaning and blast cleaning
The surface will be cleaned by vigorous wire brushing done manually to St-2
quality. This method effectively removes loosely adherent materials, but would
not affect residues of rust or mill scales that are intact and firmly adherent.
The surface will be cleaned by electric or pneumatic tools to St-3 quality. The tools
will be used carefully to prevent excessive roughing of surface and formation of
ridges and burns. This method will remove loosely adherent materials but would not
affect residues of rust or mill scales that are firmly adherent.
remove loosely adherent materials as well as adherent scales and mill scales. Prior
to application of blast, heavy deposit of oil and grease are removed by solvent
cleaning and excessive surface scales are removed by hand tools or power tool
cleaning. The surface will be cleaned to Sa-2 1/2 quality which means that to 95% of
surface area is free from all rust, mill scales and visible residues, foreign materials,
etc. The blast cleaning is not recommended for sheet metal work.
After the surface is prepared in a manner acceptable to purchaser/ consultant, two (2)
coats of Primer paints will be applied only on dry and clean surfaces. Second coat of
red oxide primer will be applied only after first coat has dried up completely. Coating of
primer will in general conform to IS:2074-92 and will be applied by brushing to ensure a
continuous film without “holidays”.
A two pack air drying epoxy polyamide with zinc dust of at least 92% zinc dust on the
dry film.
a) Intermediate paint N1
A two pack air drying high build epoxy resin based paint with MIO.
Finish paint coats will be applied over primer coats and intermediate coats after
proper cleaning and touch up of primed coats. Synthetic enamel paint comprising of
IS: 2932-95 will be used for finish coats.
Heat resistant Silicone Aluminium Paint with suitable air drying time as per IS 13183
Gr I , 25 microns per coat.
d) After cleaning the dust on the dried up primer/ intermediate paint, first coat of
synthetic enamel will be applied. After this first coat dries up hard, the surface is wet
scrubbed cutting down to a smooth finish and ensuring that at no place the first coat
is completely removed.
After allowing the water to get evaporated completely, the second finish coat of
synthetic enamel paint will be applied only after gently removing the gloss of first
coat from entire surface and it is dusted off the surface. The requirement of
workmanship will be as per IS:1477-71.
e) Equipment No. and the name of the equipment will be painted on the surface of the
equipment on visible locations in English. Service of the Pipe/Line designation with
arrow identification for the direction of flow will be painted on all pipes at visible
locations at an interval of 20 metres. Wherever pipelines are insulated, the service of
the piping and arrow mark will be painted over the clad surface.
f) For painting of structure, equipment, tanks & vessels etc. suggested colour code is
given in clause 17.2.8. For items not specified, the colour code to be followed for
piping will be in line with IS 9404:2002 (Identification of pipelines used in Thermal
Power Plants – Colour Code).
g) For insulated pipeline the finish paint will be applied at that place where colour
band is to be painted on the aluminium sheeting. The finished paint (colour band) will
be of 1m length at that place.
i) Width of band
07.11 Suggested Color Codes For Painting of Structures, equipments, tanks & vessels
etc.
S.No Item/service
1. Structures, platforms, galleries, 176 - -
ladders and handrails PHIROZI
2. Pumps, motors, compressors. Light grey 631 - -
3. Outdoor, Stand pipes, vent pipes Aluminium - - -
4. Indoor Tanks Aluminium - - -
5. Vessels & all other proprietary Light grey 631 - -
equipment (without insulation
& cladding)
6. Tanks (without insulation and Aluminium
cladding)
7. Switchgear Light grey 631 - -
8. MCC/ PDB, Control, relay Light grey 631/ - -
panels, Bus 7078 of
duct IS:1650
9. Transformers Dark admiralty 632 - -
grey
10. Machinery guards Signal red 537 - -
11. Piping (without insulation and cladding)
14 D M Water Sea Green 217 Light 557
orange
15 Soft water Sea green 217 French 166
blue
16 Bearing cooling water Sea green 217 French 166
blue
17 Potable & filtered water Sea green 217 French 166
blue
18 Service & clarified water Sea green 217 French 166
S.No Item/service
blue
19 Service air Sky Blue 101 - -
20 Instrument air blue 101 White -
21 Lubricating oil Light brown 410 Light 631
grey
22 Control oil Light brown 410 Light 557
orange
23 Transformer oil Light brown 410 Light 557
orange
25 Carbon dioxide Canary yellow 309 Light 631
grey
26 Vacuum pipes Sky blue 101 Black -
27 Drainage Black - - -
28 Stand pipes and all Aluminium - - -
Vent pipes
29 Fire Water Lines Fire red - - -
Notes:
Where band colour is specified, same will be provided at 10 meter intervals on long
uninterrupted lines and also adjacent to valves and junctions.
b) Paint will not be applied when the ambient temperature is 5 deg. C and below. Also paint
will not be applied in rain, wind, fog or at relative humidity of 80% and above.
c) Each coat of paint will be continuous, free of pores and of even film thickness without thin
spots. The first coat of finish paint at site will be applied preferably within three months of
the shop paint.
d) Each coat of paint will be dry sufficiently before application of next coat.
e) Surface which cannot be painted but require protection will be given a coat of rust
inhibitive grease according to IS:958-75 or solvent deposited compound according to
IS:1153-75 or IS:1674-60.
f) Surface which will be inaccessible after assembly will receive minimum coats of specified
primer. Surface to be in contact with wood, brick or other masonry will be given one shop
coat of the specified primer.
h) The bidder will furnish paint manufacturer’s test report or technical data sheet pertaining
to the paint selected. The data sheet will indicate among other things the relevant
standards, if any, composition in weight percent of pigments, vehicles, additives, drying
time, viscosity, spreading rate, flash points, methods of application quality of surface
preparation required, corrosion resistance properties and colour.
i) Rust preventive coating will be given to HSFG bolt and nut threads.
j) Machined surfaces / weld edges will be applied with a coating of temporary rust preventive
oil.
k) All threaded and other surfaces of foundation bolts and its materials, insulation pins,
anchor channels, sleeves will be coated with temporary rust preventive fluid and during
execution of civil works; the dried film of coating will be removed using organic solvents.
l) The temporary rust preventive coating that had already been applied on any components,
tubes, pipes etc., will be removed by suitable solvents/ heating to 350-400 Deg.C for an
hour before primer paint application-but it will be ensured that the minimum surface
cleanliness required for primer paint application will be Sp2 (equivalent to hand tool
cleaning).
m) All weld edge preparation for site welding will be applied with one coat of weldable
primer.
n) For internal protection of pipes/tubes, VCI pellets will be used at both ends after sponge
testing and ends capped. VCI pellets will not be used for SS components and composite
assemblies.
o) Wherever inside surfaces of ducts need protection till erection, two coats of red oxide zinc
phosphate primer (P1) paint to IS 12744 to a DFT of 60 microns will be applied after
power tool cleaning.
a) For a complete painting scheme of any item being painted, all types of paints are to
be procured from the same manufacturer as approved by the Purchaser.
08.01 General
ii) The Bidder has to necessarily indicate in their bid, their proposed sub vendors for the
items listed at 08.04 below. Sufficient number of sub vendors may be proposed to
meet their requirement.
iii) The items listed are not exhaustive. Hence If considered necessary the Bidder can
include additional items and indicate their proposed sub vendors for those items also.
iv) The proposed list of sub vendors furnished by the Bidder will be reviewed during
Techno Commercial / Pre-award discussions by Purchaser/Consultant and the sub
vendors will be categorized as below.
(a) Category – I: Sub vendors accepted. The acceptance shall be based on past
experience of Purchaser/Consultant.
(b) Category – II: Sub vendors enlisted for future acceptance. Such acceptance
shall be based on the various details regarding capacity, capability, experience etc of
the sub-vendor proposed by the successful Bidder. It is the responsibility of the
successful Bidder to get the details of the sub vendors under category II,
compiled and submitted to Purchaser / consultant for scrutiny and acceptance. The
acceptance criteria are mentioned below. However, Purchaser reserves the right to
accept or reject any of the proposed vendors based on information available with them.
v) The consolidated list of sub vendors under category I and category II shall be made
available to all the qualified Bidders before price cover opening.
vi) Purchaser may consider the Bidder’s proposal for inclusion of new sub vendors, if
any during post award stage for approval, based on merits, in the overall interest of
the Package, after establishing that the sub vendors proposed meet the acceptance
criteria specified. However, price advantage if any, arising out of inclusion of new sub
vendors shall be passed on to the Purchaser.
vii) For all other components/equipments/systems which are not figuring in the following
list or in the additional list furnished by the Bidder in their bid, Bidder’s standard
practice of selection of vendors may be carried out.
i) For all Mechanical, Electrical, Control and Instrumentation (Except for items mentioned
under ii and iii below)
(a) The sub-vendor shall be a manufacturer of PLC and the offered PLC should have
been supplied, erected, tested and commissioned as control system.
(b) Each or higher and running successfully with proven performance for a period of two
(2) years from the date of issue of LOA.
(c) The sub-vendor shall furnish all required information to fully satisfy the Purchaser/
Consultant regarding successful operation and high reliability of products/systems
furnished.
(c) The Bidder should furnish documentary evidence to prove (a) and (b) above
(c) For cement, minimum quantity of supply shall be 2500 MT for a single project.
(d) The Bidder should furnish documentary evidence to prove (a), (b) and
(c) above.
(a) The quality shall conform to relevant Indian standard/ International Standards.
(b) The firm should have been in the market for a minimum period of 3 years as on the
original date of Tender opening and should have supplied & used the reinforcement
steel in any industrial project.
(c) For reinforcement steel – minimum quantity of supply & used shall be 1000 MT for a
single project.
(d) The Bidder should furnish documentary evidence to prove (a), (b)
and (c) above.
(v) For structural steel (for use in Civil & Structural buildings only):
(a) The quality shall conform to relevant Indian standard / International Standards.
(b) The firm should have been in the market for a minimum period of 3 years as on the
original date of Tender opening and should have supplied & used the structural steel
in any industrial project.
(c) For structural steel – minimum quantity of supply & used shall be 1000 MT for a
single project.
(d) The Bidder should furnish documentary evidence to prove (a), (b) and (c) above.
Design, Supply, Fabrication & Erection of Steel Structures (On turnkey basis).
Technical Requirements
The bidder shall have experience of design of industrial steel structures of similar
The bidders should have successfully completed similar works in any consecutive 6
months during last 7(seven) Years ending last day of month previous to the one in
which bids are invited and shall be in compliance of either of the following:-
One similar completed work having quantity not less than the volume of steel structural
work equal 1000 MT.
The bidder shall submit attested copy of the following documentary evidence issued by
client to the bidder/ultimate purchaser, as proof of meeting the prescribed eligibility
criteria, with specific mention of information required:
(b) The Firm should have executed orders for the supply of electrodes for an order
value not less than Rs. 3 lakhs in a calendar year for any or all sizes of the subject
electrode within last three(3) years as on the original scheduled date of tender
opening..
(c) The Bidder should furnish documentary evidence to prove (a)&(b) above
In case the C&I vendor is engaging a sub Bidder for C&I works
Documentation proof shall be furnished in the form of Bid award copy and
performance certificate (End user’s certificate) to show that similar C&I erection &
installation activities were carried out and the job completed satisfactorily by the C&I
sub vendor.
The main Bidder may engage one or more sub vendor for carrying out Civil works.
However, the Civil sub-Bidder shall have the following qualifying requirements.
(a) He shall have experience in carrying out civil engineering works for Industrial
buildings / equipment foundations / high-rise buildings (3 storeys and more) etc.,
(b) He should have executed not less than 5000 Cu.M of R.C.C work in a single
agreement.
(c) Any structural steel works of quantity not less than 1000 metric tones in a single
agreement.
(d) The work in S.Nos i to iii should have been completed within the past 7 years, as
on the original scheduled date of tender opening.
(e) Bidder to furnish necessary documentary evidence to prove the above requirements
and get approval from the Purchaser, prior to engaging them for civil works.
08.04 List of items/ components for which Bidders shall submit the sub vendor list are
indicated below. Purchaser/Consultant shall categories those vendors in Category-I &
II and shall inform to all the bidders before price cover opening.
A. Common Equipments
i) Class I items: Items for which Performance Certificates shall be furnished for
approval of Category II sub vendors during detail engineering
II) Class II items: The documentary evidence for approval of Category II sub vendors shall
be in the form of Material Receipt Certificate or Site Inspection Report, etc from the end
user for having received the material by the end user.
For any other equipment/supplies which are not covered above, the
make/manufacturer’s name shall be mutually agreed between Client /Consultant
and the successful Tendere
GENERAL
09.01.01.01 The contractor shall guarantee that the equipment offered shall meet the
ratings and performance requirements stipulated for various equipment
covered in these specifications.
09.01.01.03 The Contractor shall conduct performance test and demonstrate all the
guarantees covered herein. The various tests which are to be carried out
during performance guarantee tests are listed in this chapter / section. The
guarantee tests shall be conducted by the Contractor at site in presence of
Purchaser on each unit individually.
09.01.01.04 All costs associated with the tests including cost associated with the supply,
calibration, installation and removal of the test instrumentation shall be
included in the contract price.
09.01.01.05 It shall be responsibility of the Contractor to make the plant ready for the
performance guarantee tests.
09.01.01.06 The performance tests shall be performed using only the normal number of
Purchaser’s supplied operating staff. Contractor, vendor or other
subcontractor personnel shall be used only for instructional purposes or
data collection. At all times during the Performance Tests, the emissions
and effluents from the plant shall not exceed the guaranteed emission and
effluent limits.
09.02.01 All instruments required for performance testing shall be of the type and
accuracy required by the code and prior to the test, the Contractor shall get
these instruments calibrated in an independent test Institute approved by the
Purchaser and submit the same to Purchaser prior to commencement of test.
All test instrumentation required for performance tests shall be supplied by
the Contractor and shall be retained by him upon satisfactory completion of
all such tests at site. All calibration procedures and standards shall be
subject to the approval of the Purchaser prior to commencement of test. The
protecting tubes, pressure connections and other test connections required
for conducting guarantee test shall conform to the relevant codes.
Tools & tackles, thermo wells (both screwed and welded) instruments /
devices including flow devices, matching flanges, impulse piping & valves
etc. and any special equipment, required for the successful completion of
the tests, shall be provided by the Contractor free of cost.
The Performance test shall be carried out as per the agreed procedure. The
detailed PG test procedure shall be submitted within 90 days of the
Notification of Award and finalization of PG test procedure shall be done
within 180 days from the date of Notification of Award.
09.02.02 The Performance and Guarantee test procedures shall be submitted for
equipment / system & sub system under Contractor’s scope for all
guarantees as mentioned below, as per latest international codes / standards
including correction curves, meeting the specification requirements along
with sample calculations & detailed activity plan of preparation (including
test instrumentation), conductance and evaluation of Guarantees.
09.02.03 The Contractor shall submit for Purchaser’s approval, the detailed
Performance Test Procedure containing the following:
i) Sample calculation
j) Acceptance criteria
k) Any other information required for conducting the test.
After the conductance of Performance test, the Contractor shall submit the
test evaluation report of performance test results to Purchaser promptly but
not later than one month from the date of conductance of Performance Test.
Preliminary test reports shall be submitted to the Purchaser after
completing each test run. Four (4) hard copies and two (2) soft copies of
each test report of final conducted test on each equipment / plant / system
shall be submitted to Purchaser for approval.
09.03.01 Performance Guarantee Tests on the equipments / systems not covered in
this chapter / section shall be carried out as per the procedure / test codes
specified in respective detailed specifications.
Reject the equipment / system / plant and recover from the Contractor the
payments already made
OR
Accept the equipment / system / plant after levying Liquidated Damages.
The liquidated damages for shortfall in performance indicated in Clause
09.05.00 of this chapter / section shall be levied separately for each unit.
The rates indicated in Clause 09.05.00 of this section / chapter are on per
unit basis. The liquidated damages shall be prorated for the fractional parts
of the deficiencies.
Vol. – IIA, Section 09.00 PG PARAMETERS Page 3 of 11
© 2020 MECON Limited. All rights reserved.
TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
Reject the equipment/ plant/ system and recover from the Contractor the
payments made.
Reject the equipment / system / plant and recover from the Contractor the
payments already made.
OR
i) The contractor shall guarantee that the equipment offered shall meet the
ratings and performance requirements stipulated for various equipment
covered in these specifications.
ii) The guaranteed performance parameters furnished by the bidder in his
offer, shall be without any tolerance values and all margins required for
The rate of liquidated damages and acceptable shortfall limits for different
guarantees shall be as under and such liquidated damages shall be deducted
from the Contract Price:
Note:
1. The LD values are applicable on per unit basis.
2. Each of the liquidated damages specified above shall be independent and
these liquidated damages shall be levied concurrently as applicable.
3. If the Contract currency is other that IN (Indian Rupees), then the
liquidated damages shall be in equivalent amount in Indian Rupees
based on bill selling exchange rate of State Bank of India prevailing on
the date of award of contract.
4. All these liquidated damages for shortfall in performance shall be
deducted from the contract price as detailed in accompanying
Commercial Volumes of the Tender Specification.
5. Bids will be rejected for quoting efficiency lower than 81.8 % and no
evaluation benefit given to the bidders quoting removal efficiency higher
than 81.8%.
6. Bids will be rejected in case the calculated SO2 removal efficiency is
found to be lower than 81.8 %.
** For evaluation purpose, the SO2 removal efficiency will be calculated as follows:
Note: For SO2 removal efficiency calculation both the inlet and outlet
SO2concentration shall be at 6% O2 dry basis. Outlet SO2 concentration shall be
considered as the quoted value by the bidder and with necessary corrections as
applicable, for calculation purpose.
Where ,
O2(M) – O2(WET) % by volume corrected to dry basis
O2(WET)– Specified O2 % by volume on wet basis
w – Specified Moisture % by volume
Correction for O2 %
The Contractor shall guarantee the SO2 removal efficiency for inlet
SO2concentrationcorresponding to coal analysis and 210 MW unit (100% TMCR)load.
The Guaranteed SO2removal efficiency shall not be less than 80 % at guarantee case.
The Contractor shall guarantee the lime consumption in kg/h of FGD system under
guarantee case at 210 MW (TMCR) load with required coal firing, meeting anSO2(6%
O2, dry condition) at FGD outlet at 210 MW emission of 500 mg/Nm3unit load.
The Contractor shall guarantee the total auxiliary power consumption for units, FGD plant
in normal operation at guarantee case at 210 MW unit load (100% TMCR). Bidder to refer
cl.no. 09.06.04 of this section.
SO2 removal in treated flue gas: Maximum concentration of SO2 in treated flue gas at the
exit of FGD for the unit shall not exceed the guaranteed values.
09.06.03.11 Noise
a) All the plant, equipment and systems covered under this specification shall
perform continuously without exceeding the noise level of 85 dBA over the entire
range of output and operating frequency.
b) Noise level measurement shall be carried out using applicable and
internationally acceptable standards. The measurement shall be carried out with a
calibrated integrating sound level meter meeting the requirement of IEC 651 or BS
5969 or IS 9779.
c) Sound pressure shall be measured all around the equipment at 1.0 m
horizontally from the nearest surface of any equipment/ machine and at a height of
1.5 m above the floor level in elevation.
d) A minimum of 6 points around each equipment shall be covered for
measurement. Additional measurement points shall be considered based on the
applicable standards and the size of the equipment. The measurement shall be
done with slow response on the A – weighting scale.
The performance tests shall be carried out in accordance with ASME PTC
40 (1991) code. The details of the test shall, however, be mutually agreed
upon between the Purchaser and the contractor.
The contractor shall guarantee minimum 95% availability of FGD plant for
a continuous period of 120 days. An availability guarantee test shall be
conducted to assure this level of availability for a period of 120 days as per
the procedure indicted below.
Availability “A” in %
A = TFGD X 100%
TBoiler
(i) In order to calculate the FGD availability, operation hours will be counted
normal operation of boiler excluding start-ups and shutdown periods.
Operation hours counting of the FGD plant will start on the moment of shut
down of all oil burners.
(ii) If FGD is out of operation during the boiler operation time as a result of the
Purchaser’s decision, this time will not be counted as boiler operation time
for calculating the FGD availability.
(iii) Boiler operation hours will be counted based on the recorded boiler
operation hours and the recorded data will be made available to the
Contractor by the Purchaser.
Mandatory spares have been identified by the Purchaser. Contractor can use
the mandatory spares supplied under the contract during this period in
If the calculated availability after 120 days availability test is lower than the
guaranteed value, the Contractor will undertake actions as per clause
09.04.00 (ii) of this chapter / section to achieve the guaranteed availability.
Terminal Points
FGD
The terminal points for each stage identified herein below shall be read in conjunction
with the tender drawings, scope of supply and technical specifications of various systems
covered under the package.
10.01 Mechanical
TP. NO. Items Description Remarks
arks
TP-1 Process
ss Water supply From the existing plant Bidder
dder to provide
to FGD plant
p CT blow down water necessary
essary ppumps to fill
storage tank, if required.
TP-2 Fire Waater Nearest tapping
TP-3 Flue gas inlet to ID fans outlet Refer General Layout
FGD plaant common duct drawing
TP-4 Treated Flue gas from Ducting up to inlet of Refer General Layout
FGD plaant common flue gas ducting drawing
to chimney
TP-5 Equipmment Cooling Nearest tapping from the
water (E
ECW) supply ECW supply header
network
TP-6 Equipmment Cooling Nearest tapping to the
water (E
ECW) return ECW return header
network
TP-7 Potable Water Nearest tapping from the Bidder to provide
plant potable water necessaary pumps to fill
distribution storage
ge tank, if required.
TP-8 By-Product
oduct To the outlet of telescopic
Discharge
arge chute of by-product silo
TP-9 Lime Discharge of lime
unloading trucks
TP-10 Maintena
nance Waste Up to existing drainage
water/m
misc. drain water network system
TP-11 Service Water From nearest service Bidder to provide
water header necessaary pumps to fill
storage
ge tank, if required.
TP-12 Process steam for From nearest steam a.) Temperature – 180◦C –
VAM header 200◦C
b. Pressure – 12 KSC/cm
c. Flow – 2.5 T/hr
d. Elevation of the header
– 6 meters
e. Dia of the header – 100
mm
10.02 Electrical
1250A VCB feeders, two each from station bus C1 & C2 in the existing 6.6KV station
switch gears shall be used as two incomers to each of new FGD HT switch board to be
located in the proposed FGD electrical cum control room building. Replacement of 1250A
VCB breaker by 2000A VCB breaker with necessary modification/
modification/ changes in power,
control, protection, metering & associated components like new VCB’s (2000A,40KA,
7.2KV, floor mounted), bushing CT’s core balance CT’s, relay, meters etc including
retrofitting of the new 2000A VCB in the existing 6.6KV station
station bus C1 & C2 shall be
under bidder scope.
Required HT cables from these modified 2000A VCB panel up to FGD 6.6KV new HT
SWGR board shall also be covered under the scope of FGD package(approx. distance
500mtr. Each) including laying of cable & termination
termination at both ends and allied works.
10.05 Exclusions
11.01 General layout plan indicating the available spaces for proposed FGD is as shown in the
tender drawing. It shall form the basis for further elaboration by the Bidder for the plant
facilities, which are in his scope.
11.02 While preparing the detailed layout, planning the facilities in the Bidder’s scope and
deciding upon the transportation and construction / erection strategy and functional
requirements, the Bidder shall ensure the following aspects:
i) Face of the buildings and facilities shall be located in such a way so as to have an
offset of minimum 20 m with respect to center line of double lane road and 15
meter with respect to center line of single lane road. The spacing between various
buildings and facilities shall be suitably decided so as to avoid interference
between the foundations.
ii) The entire construction activity shall take into account the commissioning of the
units.
ii) The area for construction/erection facilities like lay-down, pre-assembly, offices
and stores is to be managed by the Bidder within the areas available in General
Layout Plan.
v) All the buildings and facilities shall be approachable by the fire tenders.
vi) All statutory requirements including safe distances between various facilities as
per applicable rules/acts/laws including local bye-laws are met.
12.01 General
12.01.01 As part of the Bidder’s activity, the Bidder shall be responsible for proper
engineering and co-ordination of activities during various phases of execution of the
contract. The Bidder shall identify a person, designated as Project Manager, with whom
the Purchaser/Consultant shall interact on matters related to engineering as well as
execution of the project. The Project Manager shall be the single-point contact person
on behalf of the Bidder and shall be responsible for all engineering co-ordination. The
Purchaser/Consultant shall interact with the Project Manager only on all matters of
co-ordination between the Purchaser/Consultant and the Bidder or on matters involving
the Bidder, his manufacturing units and sub-vendors. For the purpose of expediting, the
Purchaser/Consultant may sometimes interact with the manufacturing units or sub-
vendors of the Bidders. However such interaction shall not, under any circumstance,
dilute the responsibility of the Bidder to provide a fully engineered and co-ordinated
package under this contract.
The Bidder and his sub-vendors shall be called upon to attend engineering co-
ordination meetings with the other Bidders and the Purchaser/Consultant during the
period of execution of contract. The Bidder including his sub- vendors shall attend
such meetings at their own cost. Normally coordination meeting with respect to any
specific design problem shall be held at the Purchaser/Consultant’s office.
The Bidder shall agree to cooperate with the Purchaser’s other Bidders and freely
exchange with them such technical information as is necessary to obtain the most
efficient and economical design and to avoid unnecessary duplication of efforts. The
Consultant shall be provided with copies of all correspondences addressed by the
Bidder to other Sub- contractors in respect of such exchange of technical information.
design margins etc. including that for structural steel and civil work shall be outlined
and these shall form the basis for the detailed engineering work.
12.04.02 Engineering work shall be performed on modern and proven concepts and
internationally accepted good engineering practices but fully compatible with the
Indian environments. Purchaser shall have the right to review and approve the
engineering work by themselves and/or through consultant and ask for any
clarifications and changes/modifications to the work performed by Bidder.
12.04.03 At any stage during the performance of assignment, the Bidder may be required to
make certain changes/modification/improvements in design/drawing/other documents
which are applicable to FGD Package which in the opinion of the
Purchaser/Consultant could result in better improved design, layout, operability, plant
availability, maintainability, reliability or economy of the plant and its systems / sub-
systems in view of revised and more accurate information/data available at a later
date(s) or feedback(s) received during execution/operation of similar units. Such
changes/modifications/ improvements required could be identified by
Purchaser/Consultant and mutually discussed. Purchaser/Consultant requires the Bidder
to incorporate such action in the subject assignment appropriately without any
additional cost liability to the Purchaser/Consultant and it shall be within the
responsibilities and scope of the Bidder.
12.04.04 During the course of review of detailed engineering stages, it may be essential in the
opinion of Purchaser/Consultant to obtain certain classified data for review purposes
only. In case Purchaser/Consultant so desires, the Bidder shall submit such data to
Purchaser/Consultant.
by the Bidder from time to time, as detailed designs are developed, shall
be submitted for Purchaser/Consultant's approval before the work is taken up.
Revisions, corrections, additions to drawings and schedules shall not be considered to
change the scope of work.
12.04.08 Preparation of detailed technical specifications including data sheets, tender drawings
and bill of material for all bought out items and also finalization of corresponding Sub-
vendors.
12.04.10 Preparation of civil assignment drawings (furnishing 100% input information) for all
equipment showing foundation details and full details regarding equipment loads, floor
openings, details of embedment etc. required for preparation of civil design
construction drawings by the bidder for his scope of work. These documents shall be
preceded by appropriate design calculations, static and dynamic analysis as necessary.
12.04.11 Preparation and finalization of process piping and instrumentation diagrams and
schematics, complete in all respects for all the sub-packages of the FGD package.
12.04.12 Preparation of consolidated schedules and bills of materials, including line numbers, tag
numbers, source of supply, service conditions, specifications, materials, types and
connections details, quantities for items of the plant including dampers, steam traps,
strainers, instrumentations, ducting.
12.04.13 Sizing of all piping and equipment as per the stipulated design criteria; carrying
out of flexibility analysis/dynamic analysis as necessary; hangers & support
engineering.
12.04.16 Certification and submission of final as-built drawings for all sub-packages.
12.04.17 Preparation and compilation of all drawings, schedules and instructions, which may be
required at site, whether separately, mentioned or not.
12.04.18 All erection and assembly drawings, which may be required at site.
12.04.19 For all bought out items, the Bidder shall provide complete material/ component
list along with detail specification, drawings component part no. etc. during detail
engineering stage prior to final approval. Such approved drawing/document shall be
made available at site in adequate number prior to commencement of work. Moreover,
such document/drawing shall be provided in soft form (CD) also.
12.05.01 Within fifteen (15) days of issue of LOA by the Purchaser/Consultant, the Bidder
shall furnish a schedule of drawings and design document to be submitted by him
to the Purchaser/Consultant indicating dates against each drawing/document.
12.05.02 The documents shall be divided into two categories: a) for approval and b) for
information/further engineering and co-ordination by the Purchaser/Consultant.
12.05.03 In preparing this schedule, the Bidder shall consider fifteen days from date of receipt of
drawings/documents for review and comments by the Purchaser/Consultant for each
submission of a document.
12.05.04 This document submission schedule shall require approval by the Purchaser/Consultant.
12.05.05 All contract documents shall be marked, without fail, with the name of the Purchaser,
the Consultant, the Project, the specification title and number and the unit designation.
12.05.07 Unless specified otherwise, the following categories of documents/ drawings would
require approval of the Purchaser/Consultant. The design calculation, drawings and
documents shall be approved by the consultants on behalf of the Purchaser.
i) System scheme and instrumentation diagrams.
ii) Design basis justifying selection of equipment & process parameters where not specified
in the Contract.
iii) Equipment data sheets and general arrangement drawings, Civil design, Civil
G.A. and R.C.C. drawings and structural drawings.
iv) Materials of construction with cross-sections.
v) Layout drawings.
vi) Operation logic diagrams.
vii) Typical control circuit.
viii) Cable schedule and interconnection chart.
ix) Drive/feeder wise control scheme showing all external interfaces.
x) Drawings of Instrumentation and Control.
xi) Equipment foundation drawings and civil assignment drawings.
12.05.08 Unless specified otherwise, the following categories of documents/ drawings would be
treated for information/further engineering by the Purchaser/Consultant. The Bidder
shall, however, incorporate all additional information and clarifications in these
documents/drawings as and when desired by the Purchaser/Consultant.
i) Equipment GA drawings, Equipment cross-section drawings, product literature etc.
which are of proprietary nature.
ii) Predicted performance curves of equipment.
iii) Various bills of quantity, schedules etc.
iv) Piping fabrication drawings, isometrics etc.
v) Panel wiring diagrams.
vi) Instruction/ Operation manuals.
vii) Service manuals and troubleshooting guide for C & I system and instruments.
12.05.09 In essence, the Bidder is solely responsible for corrections and adequacy of design &
engineering for documents under this category.
12.05.10 Upon review, the Purchaser/Consultant shall put his remarks and one commented
copy shall be returned to the Bidder.
12.05.11 The Bidder's work shall be in strict accordance with the finally approved drawings and
no deviation shall be permitted without written approval of the Purchaser/Consultants.
12.05.12 Except key plan/general yard plan, any layout drawing requiring scrutiny shall not be
drawn to a scale less than 1:50.
12.05.13 Apart from required number of hard copies, all drawings/documents generated for this
project from the last tier of respective sub contractors shall be submitted also in soft
from.
12.06 Drawings/ Documents to be submitted by the Bidder along with the Bid
The Bidder shall submit along with his bid all documents/drawings as requested
in respective specifications. The documents shall include but not be limited to the
following:
i) All Bid proposal sheets duly filled up. Editable soft copies for documents like data
sheets, list of mandatory spares, sub vendors, tools & tackles, etc. preferably in
word/excel format (additionally for compilation purposes), along with the copies of
signed non editable formats
ii) Scheme drawings indicating scope of supply and service as offered by the Bidder
indicating clearly exclusions, if any.
iii) List of terminal points of the package offered together with quality and quantity of
various input (i.e. water, air, electricity etc.) as required from the Purchaser at such
interfaces.
iv) Equipment GA, Layout, Design Calculations, interlock and other write- up,
catalogues/literature etc. as required for clear understanding of the bid submitted.
v) L-1 network indicating target dates for intermediate milestones and final commissioning
of equipment supplied; this network shall be supplemented by a detailed write-up on
proposal procedure of project implementation, deployment schedule for Key personnel
with their bio- data, schedule of construction machinery etc.
vi) List of proposed suppliers for all bought out items as listed
vii) Drawing showing termination point with Purchaser and relevant information
required from Purchaser.
viii) List of consumption of Utilities for the system covered under the scope of bidders.
12.07 Documents, Data and Drawings to be furnished by Bidder after Award of the
Contract
12.07.01 Each of the plant and equipment pertaining to the Sub-packages of FGD shall be fully
integrated, engineered and designed to perform in accordance with the technical
specification. All engineering and technical services required ensuring a completely
engineered plant shall be provided in respect of mechanical, electrical, control &
instrumentation, civil & structural works.
12.07.02 The Bidder shall furnish engineering data/drawings in accordance with the schedule of
information as specified in Technical Specification and data sheets.
12.07.04 The documentation that shall be provided by the Bidder is indicated in various sections
of specification. The documentation shall include but not be limited to the following:
Bidder shall furnish for each sub-package Design basis Report, data sheets, drawings,
documents etc. The above documents shall contain the following as a minimum for each
sub-packages.
vi) Operation Philosophy and the control philosophy of the FGD Plant.
vii) General Layout plan of the power station incorporating all facilities in Bidder's as well
as those in the Purchaser's scope. This drawing shall also be furnished in hard form as
well as soft form (Auto CAD format) in compact disc to the Purchaser/Consultant for
engineering of areas not included in Bidder's scope.
viii) Basic layouts and cross sections or various floor elevations for FGD areas included in
the scope of the Bidder.
ix) Documentation in respect of Quality Assurance System as listed out elsewhere in this
specification.
x) The successful Bidder shall furnish Design basis report for various sub packages.
xi) After approval of Design Basis Report for each sub-packages, Bidder shall furnish the
following detailed technical specification of all sub- packages.
(a) Layouts, general arrangements, elevations and cross-sections drawings for all
the equipment and facilities of the sub-packages.
(b) Flow diagrams, Process & Instrumentation Diagrams alongwith write-up and
system description.
(c) Piping isometric, composite layout and fabrication drawings.
(d) Piping engineering diagrams, pipe and fittings schedules, valve schedules, hanger
and support schedules, insulation schedules.
(e) Technical data sheets for all bought out and manufactured items. Bidder shall use
the specifications as a base for placement of orders on their sub-vendors.
(f) Detailed design calculations for components, system/sub-system, piping etc.,
wherever applicable including sizing calculations for all auxiliaries as per criteria
specified elsewhere in specification.
(g) Comprehensive list of all terminal points which interface with Purchaser's
facilities giving details of location, terminal pressure, and temperature, fluid
handled & end connection details, forces, moments etc.
(h) Power supply single line diagram, block logics, control schematics,
electrical schematics, etc.
(l) Instrument schedule, measuring point list, I/O list, Interconnection & wiring
diagram, functional write-ups, and installation drawings for field mounted
instruments, logic diagrams, control schematics, wiring and tubing diagrams
of panels and enclosures etc. Drawings for open loop and close loop controls
(both hardware and software). Motor list and valve schedule including type of
actuator etc.
(m) Alarm and annunciation list and alarms & trip set points.
(o) Type test reports and power system stability study report.
(p) Control system configuration diagrams and card circuit diagrams and
maintenance details.
(y) The Bidder while submitting the above documents / drawings for approval /
reference as the case may be, shall mark on each copy of submission the reference
letter along with the date vide which the submissions are made.
i) Erection strategy.
i) The operating and maintenance instructions together with drawings (other than shop
drawings) of the equipment, as completed, shall be in sufficient detail to enable the
Purchaser to operate, maintain, dismantle, reassemble and adjust all parts of the
equipment. They shall give a step by step procedure for all operations likely to be
carried out during the life of the equipments of each sub-packages of -FGD including,
operation, maintenance, dismantling and repair. Each manual shall also include a
complete set of drawings together with performance/rating curves of the equipment and
test certificates wherever applicable. The contract shall not be considered to be
completed for purposes for taking over until these manuals have been submitted to the
Purchaser.
ii) If after the commissioning and initial operation of the plant, the manuals require
any modification / additions / changes, the same shall be incorporated and the updated
final instruction manuals shall be submitted to the Purchaser for records.
iii) A separate section of the manual shall be for each size/ type of equipment and
shall contain a detailed description of construction and operation, together with all
relevant pamphlets and drawings for each sub-packages of -FGD.
v) Detailed specifications for all the consumables including lubricant oils, greases,
and chemicals etc. system/equipment/assembly/sub D assembly - wise required
for the complete plant.
The Bidder shall submit to the Purchaser a preliminary plant hand book preferably in
A-4 size sheets which shall contain the design and performance data of sub-packages
including
The Bidder shall submit a Project Completion Report after successful completion of
trial operation and at the time of handing over the plant for all the sub-packages of -
FGD package.
furnished to Purchaser/Consultant.
iv) All documents/text information shall be in latest version of MS Office.
v) All drawings submitted by the Bidder including those submitted at the time of bid
shall be in sufficient detail indicating the type, size, arrangement, revision history,
reference drawings/documents, legend, weight of each component for packing and
shipment, the external connection, fixing arrangement required, the dimensions
required for installation and interconnections with other equipments and materials,
clearance and spaces required between various portions of equipment and any other
information specifically requested in the drawing schedules.
vi) Each drawing submitted by the Bidder (including those of sub-vendors) shall bear a title
block at the right hand bottom corner with clear mention of the name of the
Purchaser, Consultant, name of the Project, system designation, the specifications
title, the specification number, drawing/document number and revisions. If
standard catalogue pages are submitted the applicable items shall be indicated therein.
All titles, notes, markings and writings on the drawing shall be in English. All the
dimensions should be in metric units.
vii) The Bidder shall also furnish a “Master Drawing List” which shall be a comprehensive
list of all drawings/ documents/ calculations envisaged to be furnished by him during
the detailed engineering to the Purchaser/Consultant. Such list should clearly indicate
the purpose of submission of these drawings i.e. “FOR APPROVAL” or “FOR
INFORMATION ONLY”.
viii) Similarly, all the drawings/ documents submitted by the Bidder during detailed
engineering stage shall be stamped “FOR APPROVAL” or “FOR INFORMATION”
prior to submission.
ix) The furnishing of detailed engineering data and drawings by the Bidder shall be in
accordance with the time schedule for the project. The review of these documents/ data/
drawings by the Purchaser/Consultant will cover only general conformance of the data/
drawings/ documents to the specifications and contract, interfaces with the equipments
provided by others and external connections & dimensions which might affect plant
layout. The review by the Purchaser/Consultant should not be construed to be a
thorough review of all dimensions, quantities and details of the equipments, materials,
any devices or items indicated or the accuracy of the information submitted. The review
and/ or approval by the Purchaser/Consultant shall not relieve the Bidder of any of his
responsibilities and liabilities under this contract.
x) After the approval of the drawings, further work by the Bidder shall be in strict
accordance with these approved drawings and no deviation shall be permitted
without the written approval of the Purchaser/Consultant. Approved
drawings/documents by Purchaser/consultant, bearing stamp of approval, shall be
xi) All manufacturing, fabrication and execution of work in connection with the equipment /
system, prior to the approval of the drawings, shall be at the Bidder’s risk. The Bidder
is expected not to make any changes in the design of the equipment /system, once they
are approved by the Purchaser/Consultant. However, if some changes are necessitated
in the design of the equipment/system at a later date, the Bidder may do so, but such
changes shall promptly be brought to the notice of the Purchaser/Consultant indicating
the reasons for the change and get the revised drawing approved again in strict
conformance to the provisions of the Technical Specification.
xii) Drawings shall include all installations and detailed piping layout drawings. Layout
drawings for all piping of 65 mm and larger diameter shall be submitted for review/
approval of Purchaser/Consultant prior to erection. Small diameter pipes shall however
be routed as per site conditions in consultation with site authority/representative of
Purchaser/Consultant based on requirements of such piping indicated in approved /
finalized Flow Scheme/Process & Instrumentation Diagrams and/or the requirements
cropping up for draining & venting of larger diameter piping or otherwise after their
erection as per actual physical condition for the entire scope of work of this package.
xiii) Assessing & anticipating the requirement and supply of all piping and equipment shall
be done by the Bidder well in advance so as not to hinder the progress of piping &
equipment erection, subsequent system charging and its effective draining & venting
arrangement as per site suitability.
xv) Drawings must be checked by the Bidder in terms of its completeness, data adequacy
and relevance with respect to engineering schedule prior to submission to the
Purchaser/Consultant. In case drawings are found to be submitted without proper
endorsement for checking by the Bidder, the same shall not be reviewed and returned to
the Bidder for re-submission. The Bidder shall make a visit to site to see the existing
facilities and understand the layout completely and collect all necessary
data/drawings at site which are needed as an input to the engineering. The Bidder
shall do the complete engineering including interfacing and integration of all his
equipment, systems & facilities within his scope of work as well as interface
engineering & integration of systems, facilities, equipment & works under Purchaser’s
scope and submit all necessary drawings/ documents for the same.
xvi) The Bidder shall submit the drawing/data/document in specified number of copies
in this specification for Purchaser/Consultant’s review and approval. The
Purchaser/Consultant shall review the drawings and return one (1) copy to the Bidder
authorizing either to proceed with manufacture or fabrication, or marked to show
changes desired. When changes are required, drawings shall be re-submitted promptly,
with revisions clearly marked, for final review. Any delays arising out of the failure of
the Bidder to submit/rectify and resubmit in time shall not be accepted as a reason for
delay in the contract schedule.
xvii) All engineering data submitted by the Bidder after final process including review
and approval by the Purchaser/Consultant shall form part of the contract documents
and the entire works covered under these specification shall be performed in strict
conformity with technical specifications unless otherwise expressly requested by the
Purchaser/Consultant in writing.
The successful bidder will be required to furnish all the necessary Design basis reports
(DBR), drawings, data sheets etc. of package with appropriate “Status” stamp in
adequate number of copies as discussed and agreed upon during the first meeting after
acceptance of Letter of Award along with soft copy of the above mentioned
drawings/documents in NLC framed system DEMS.
12.16.02 The draft format for this report shall be furnished to the Purchaser/Consultant within
four (4) weeks of the award of the contract, which shall then be discussed and finalized
with the Purchaser/Consultant.
12.17.01 The Bidder shall be called upon to organize and attend the Design/ Co- ordination
Meetings with the Purchaser/Consultant’s representatives, Project Consultant during
the period of contract. The Bidder shall attend such meetings at his own cost at
mutually agreed venue as and when required and fully co-operate with such persons and
agencies involved during the discussions.
12.17.02 The Bidder should note that Time is the essence of the contract. In order to expedite the
early completion of engineering activities, the Bidder shall submit all drawings as per the
agreed Engineering Information Submission Schedule. The drawings submitted by
the Bidder will be reviewed by the
Purchaser/Consultant as far as practicable within one month from the date of receipt of
the drawing.The comments of the Purchaser/Consultant shall then be discussed across
the table during the above co-ordination Meetings wherein best efforts shall be made
by both sides to ensure the approval of the drawing.
12.17.03 The Bidder shall ensure availability of the concerned experts / consultants/ personnel
who are empowered to take necessary decisions during these meetings. The Bidder
shall be equipped with necessary tools and facilities so that the drawings/documents can
be resubmitted after incorporating necessary changes and approved during the meeting
itself.
12.17.04 Should any drawing remain unapproved for more than six (6) weeks after it’s first
submission, this shall be brought out in the monthly Engineering Progress and Exception
Report with reasons thereof.
12.17.05 Any delays arising out of failure by the Bidder to incorporate Purchaser/Consultant’s
comments and resubmit the same during the TCM/ECM shall be considered as a
default and in no case shall entitle the Bidder to alter the Contract completion date.
TENDER SPECIFICATION
FOR
SEMI DRY FLUE GAS DESULPHURIZATION
(FGD) SYSTEM & ITS AUXILIARIES
VOLUME – II B
TECHNICAL SPECIFICATION
MECON LIMITED
RANCHI – 834 002
INDEX TO VOLUMES
Volumes Title
Volume – I Commercial
Volume – II Technical
Volume - IIA General Technical Specification
Section 01.00 Preamble
Section 02.00 Intent of Specification
Section 03.00 Project Information
Section 04.00 Special Instructions to Bidder
Section 05.00 Scope of Work, Supply & Services
Section 06.00 Quality Assurance system / Requirement
Section 07.00 Painting
Section 08.00 Finalization of Sub-vendors / Sub-contractors
Section 09.00 Performance Guarantees
Section 10.00 Terminal Points & Exclusion
Section 11.00 Layout and Maintenance Requirement
Section 12.00 Drawings / Documents to be submitted along with Bid / Offer
and after award of contract
Volume - IIB Technical Specification
Section 01.00 Flue Gas Desulphurization System (Semi Dry)
Section 02.00 Technical Data Sheets – Mechanical
Volume -IIC Balance of Plant (BOP) Facilities
Section 01.00 Water Supply System
Section 02.00 Air Conditioning & Ventilation System
Section 03.00 Elevators, Cranes & Hoists
Section 04.00 Fire Protection System
Section 05.00 Piping, Valves & Fittings
Section 06.00 Thermal Insulation, Lagging, Cladding
Section 07.00 Compressed Air System
Volumes Title
Volume - III Instrumentation & Control System
Volume -IV Electrical System
Volume -V General Civil, Architectural & Structural Works
Volume -VA Civil Works.
Volume - VB Architectural Works
Volume - VC Structural Works
Volume - VI Mandatory Spares and Tools & Tackles
Volume - VII Tender Drawings
The FGD system shall be generally in line with the following or equivalent
proven technology.
The semi dry FGD flue gas treatment system is to be located after removal of
particulate matter from flue gas by existing electrostatic precipitator. The clean
gas is discharged to the stack. The FGD system shall be based on Circulating Dry
Scrubber (CDS) or Spray Dryer Absorption (SDA) technologies. Circulating Dry
Scrubber (CDS) type semi dry FGD system shall be the preferred technology for
4X210 MW MTPS-I plant.
Each units shall be provided with two nos. independent Booster fans (2 x 50%
capacity) at the downstream of the ID Fans. The connection between the boiler ID
fan outlet and stack also consists of a bypass bi-plane damper which is used to
bypass the complete FGD system, if needed.
Flue Gas from Booster fan discharge shall be taken to the inlet of the CDS reactor
inlet from bottom side. In the CDS reactor, SO2 in flue gas shall be removed by
injecting lime and water spray, or a prepared mixture of lime and water fed via
mechanical feeder. The hot untreated flue gas is introduced via venturi tube(s) at
the bottom of the reactor vessel. Enough water is sprayed to maintain the optimum
reaction temperatures above adiabatic saturation and overall dry reaction products.
To improve the utilization of reagent, a portion of the reaction product collected in
the downstream fabric filter is recycled back into the reaction tower.
Alternatively, in a Spray Drying Absorption technology, Hot, untreated flue gas
is introduced into the Spray Dryer Absorber via a flue gas disperser and
subsequently comes into contact with a highly reactive absorbent that will be
atomized by a rotary atomizer. An efficient contact between flue gas and absorbent
allows for rapid mass transfer of acidic components from the flue gas into the
alkaline absorbent. The absorbent neutralizes the absorbed acid. While this reaction
takes place, the water is evaporated, thus forming a dry powder. A fraction of the
dry powder will be deposited at the bottom of the absorber chamber whereas the
main part is carried to the downstream fabric filter while the cooled flue gas
leaves the chamber.
Clean gas from the scrubber / absorber shall be taken to Chimney through fabric
filter. Clean flue gas from the dry FGD s yst em shall be discharged through a
flue can located in the individual chimney’s of 4x210 MW MTPS-I units.
Both the above processes result in a stable and dry end product, mainly consisting
of fly ash and various calcium compounds.
02.01 General
a) The FGD system shall be installed downstream of the ID fans and shall be based
on semi dry FGD process to achieve the required SO2 capture. The FGD System
shall be designed to be in operation when Steam Generator is in operation.
b) The unit must be capable of handling its TMCR output with no limits as to
duration, with maximum availability, rapid load variations and frequent stops and
starts without suffering any damage to the equipment and to the fittings, other than
normal wear. The FGD system shall be designed and manufactured for a life span
of 25 years.
c) The FGD system shall be a semi dry hydrated or slaked lime-based system. The
system shall include a single reactor. A modular concept with multiple reactor
towers may also be proposed for CDS system. Two (2) nos. working booster fans
for each Unit shall be included downstream of existing ID (induced draft) fans. The
system shall be able to meet guaranteed SO2 as per performance guarantee
schedule.
d) The FGD and the ancillary facilities shall be suitable for unlimited operation
with all transients and at any load between the minimum and maximum load point
of the Steam Generator. Further, the FGD plant shall be suitable for an unlimited
operation at any pollutant concentrations between minimum and maximum without
exceeding the emission values of SO2 and emission as indicated in Vol. IIA ,
Section 3 under various operating conditions.
e) FGD system shall be capable of meeting emission while in operation from 25%
to 100% TMCR on sustained basis.
g) In case of failure of the Steam Generator and ancillary equipment, the FGD plant
shall be brought automatically to the off-load operation, without restriction by the
current load case, by suitable measures.
i) Draining and flushing which are required even during short time outages or an
emergency shutdown shall be started automatically and by remote control from the
Control Room.
j) The FGD system and all the associated auxiliaries shall be designed to comply with
the requirements stipulated under ‘Guarantee Point’ and ‘Design Point’
conditions.
k) The reagent injection system shall have the flexibility in capacity to cater to
improved SO2 reduction efficiency resulting from any future change in
environmental emission norms. Bidder to indicate the design margin and relevant
features included in his offer.
already been adequately developed and have demonstrated good reliability under
similar or more arduous conditions elsewhere.
b) The Bidder shall submit with the offer, comprehensive information on how the
mass balance, lime consumption, by-product generation etc. of the proposed design
has been arrived at. The Bidder shall also submit along with the offer, a detailed
write up on the proposed design features with recent design modifications, if any,
and their specific advantages over the previous designs.
The Bidder shall offer the best design to accommodate the Flue Gas
Desulphurisation (FGD) System and Lime & by-product handling & storage
system within the confines of the space available. The location of FGD System has
been indicated in the Attached Layout Plan.
Owner envisages carrying out the capital overhaul of the unit once in five (5) years.
The design and materials for various equipment/auxiliaries etc. shall be selected by
the Bidder keeping in view the above requirement of the Owner, such that no
major repairs/replacements, requiring shutdown of the unit, are needed in between
the capital overhauls.
02.07 Maintenance
The Bidder shall provide adequate handling facilities & approach as for carrying
out on-line and off-line maintenance of the FGD system and its auxiliaries. In order
to carry out on-line maintenance, it shall be possible to access, isolate, readily
disassemble, repair and reassemble the equipment supplied in the shortest period.
Cage Ladder/Monkey ladder shall not be allowed. Only proper staircase shall be
provided
a) The complete FGD system and the associated auxiliaries shall be designed as per
the bidder’s proven design and standard industrial practices. Only field proven
materials for similar application shall be used for the system.
b) The FGD System shall be designed to meet all the specified operating
conditions. The values indicated for FGD sizing shall be considered as minimum
design criteria. These shall be modified to more conservative values if Bidder
experience warrants the same. Utilization of these values in no way relieves the
Bidder of his responsibility to meet all the guarantee requirements. The Bidder
shall also furnish the detailed calculations and data along with his Bid to establish
as to how the Bidder will meet the performance and efficiency requirements both at
design/ guarantee points as specified in FGD sizing criteria.
100% leak tight with seal air fans under the above conditions.
f) The blade and other components of the bypass damper as per bidder’s
standard practice.
g) The gates & dampers shall be controlled from the control room. Provision shall
be made for automatic opening of the by-pass damper in case of emergency.
The gates shall have provision for manual operation, through a hand wheel. The
force required for manual operation of the gate shall not exceed 35 kg (max.) at the
rim of the hand wheel.
h) The isolating gates shall be provided with locking devices to permit locking in
fully closed position.
i) All gates shall be designed to withstand the operating air and flue gas
temperature without distortion.
j) All guillotine gates shall be located in horizontal duct to avoid fly ash build up
when in closed position and shall be of top entry type.
k) Bidders shall indicate opening/closing time for each damper in bid data
sheets. The biplane damper shall be capable of opening during emergency
conditions within a time of 15-20 secs. Bidder to select the proper damper
accordingly.
l) The operation of dampers shall be suitably interlocked with booster fans, ID fan
and existing controls of the unit to prevent mal operation leading to damage of the
unit or FGD system.
m) Weather hood to prevent rain water entry and accumulation shall be provided at
damper top. The seal air pressure always at least 50 mmwc (g) higher than
maximum flue gas pressure
a) The Booster Fans shall be located downstream of the ID Fans (Induced Draft Fans)
in the inlet duct to reactor/absorber to take care of the additional pressure drop in
the FGD System, fabric filter bag house & ducting and maintain required chimney
inlet pressure over the entire load range with any one or both Booster fans in
operation (as applicable for the offered configuration), in conjunction with one or
both ID fans in operation while firing the specified range of fuels.
b) Fans shall be capable to cater to 100% BMCR (flow & Pressure). Adequate
margin (flow & pressure) shall be provided for test block condition.
c) Salient Design Requirement:
Table-6.2 Booster Fan Design Parameter
S. No. Description Design
1. Type of Fans Constant speed, axial or centrifugal type
2. Quantity 2x50% for each absorber, to match the
combined
flow of two ID Fans
Note:
1. Booster Fan shall have a minimum stall margin of 10% over the design
duty points.
2. The bidder shall furnish the fan sizing calculations for approval of
Owner during detail engineering.
d) The booster fans of the axial, single stage shall be provided with variable pitch
type, renewable liners and vibration isolation system (VIS) foundation. In case of
In the pneumatic process, measured quantities of lime, air and water are introduced
into the hydration reactor for intimate mixing and conversion to calcium
hydroxide. Hydrated lime product is separated from the hydrator exhaust vapours
in a downstream cyclone and then collected in an intermediate hopper. From the
hopper, the hydrated lime can be fed directly or via hydrated lime storage silo to
the CDS reactor. If hydrated lime is fed directly to the CDS reactor, then this
system does not require a dedicated fabric filter for de-dusting.
In the mechanical process, a double shaft stirrer pre- mixer followed by a hydrating
and maturing chamber can be used for controlled hydration process involving
lime and water. Bag filter shall be provided for de-dusting in this process. The
hydrated lime from hydrator shall be transferred to the hydrated lime silo located
near the CDS reactor via suitable pneumatic conveying system.
A dosing valve shall be provided at discharge of intermediate lime silo and
hydrated lime product hopper. The hydrated lime shall be fed to the CDS -
reactor/ recycle mixer at a controlled rate to meet the required SO2 removal.
If a modular type CDS FGD is offered, then each module of CDS reactor shall be
provided with a dedicated hydrator-mixer.
The hydrated lime preparation system shall be sized to produce and deliver the
required quantity of hydrated lime for SO2 removal as designed.
be designed to ensure that the fluidized by-product is transferred from the fluid
trough to the by-product transport system without interruption, plugging, or
bridging, shall not impact the Owner's ability to effectively operate the
system, and provide necessary means for equipment maintenance.
j) Fluid trough shall have a minimum 250mm diameter outlet flange to connect to
by-product transport system.
k) In a modular system, each module may be provided with a dedicated rotary
feeder that receives by-product material from the Fluid trough. The rotary
feeder introduces material into the each dedicated Reactor mixer at the required
feed rate.
l) Reactor mixer shall be provided with a dedicated valve station for the mixer
process water and instrument air feed.
m) Platform shall be provided for easy access to water/air injection nozzle to
facilitate ease of maintenance. If temporary access is considered, e.g., rolling stairs,
design must consider safety and ease of use.
n) Mixer water injection nozzles shall be constructed of a stainless steel and
suitable for long term operation. Nozzle design shall include an air shield to
mitigate build up at the nozzle tip. 20% or minimum 5 numbers nozzles in spare
shall be considered.
operation. The Reactors shall be designed to avoid corrosion, slurry solid build-up,
scaling, acid attack, moisture attack, vibration fatigue, chloride corrosion, erosion,
and cracking. A minimum 1.6 mm of corrosion allowance shall be provided,
though the Reactors shall be designed and constructed with enough erosion
resistant margin per manufacture's recommendations.
c) ASTM A-514 or equal steel in high wear vessel wall areas shall be provided as
required.
d) Vessel design shall minimize internal structural supports.
e) The Reactors shall be designed to support the weight of dry waste deposits on the
internal walls and the bottom section filled with waste deposits.
f) The Reactors shall be insulated to minimize flue gas temperature loss and noise
propagation.
g) A minimum of two access doors shall be furnished. Doors shall be placed to
allow for inspection and maintenance of key components, including turning vanes,
Reactor lower screw, or inlet teardrop venturi. Doors shall be furnished with
external latches and tightening devices, which allow for gasket shrinkage and still
maintain zero leakage. Doors shall be furnished with means to lock in the open
position to prevent accidental closing with maintenance personnel inside. All
access doors subject to high temperatures shall be insulated. Other inspection
access doors shall be included as required.
h) Un-entrained material in the Reactor will be conveyed to the by-product
handling system. Bidder shall provide a reactor screw conveyor from the bottom of
the Reactor to the by- product material handling system.
i) Bidder shall provide a local control panel for the reactor screw conveyor.
j) Material collected at the bottom of the Reactor that cannot be re-entrained in the
flue gas stream shall be automatically conveyed to the by-product handling
system, while the Reactor is in operation. The bottom of the vessel shall also be
equipped with a port and valve to allow for manual clean out.
k) The system shall be designed to prevent by-product build-up. The Bidder shall
ensure that there is no significant impact to the Owner's ability to effectively
operate and maintain the equipment.
l) The vessel shall be provided with necessary instrumentation, control, and
alarms to prevent over-addition of water to the recycle by-product and lime. Bidder
shall describe in operating description how the water injection system will react to
and assist to control• extreme flue gas temperature rise (e.g. caused by air preheater
failure).
m) An overhead monorail and trolley system shall be provided for easy removal of
the equipment during maintenance.
n) Provide turning vanes, as required, to provide uniform flue gas flow through the
Reactors and ductwork Material shall be A36 carbon steel or AR 350 (or equal)
abrasion resistant steel as required per previous operating experience.
a) Provide one complete SDAs with all necessary internals, cone hoppers, and
attachments. Design to minimize flooding and scaling, solids deposition, or
erosion of interior surfaces. Provide supports for SDA inlet duct to carry the
load directly to grade.
b) Provide instrumentation and connections for monitoring process variables in
accordance with Seller's process design and as specified in this specification.
c) Provide rotary atomizers complete with all necessary accessories for one
SDA vessel designed for all the units of 210 MW to meet guaranteed
emission level. 1 standby spare atomizer complete with all necessary accessories
shall be provided.
d) Design the atomizer system(s) to operate continuously.
e) Provide rotary atomizer(s) complete with drive motor(s), gear drives, and the
following:
(i) Complete self-contained oil lubrication systems, including pumps,
reservoirs, cooling heat exchangers, cooling fans, and other accessories.
Lube oil piping shall be stainless steel.
(ii) Vibration monitoring systems (with local indication) including high
vibration alarm and shutdown features for each rotary atomizer
(iii) Quick disconnects at the atomizer for all electrical and process connections
to allow for rapid removal and replacement of atomizer.
(iv) System shall include a spare rotary atomizer complete with all accessories
required to allow expedient installation and operation.
(v) Independent dedicated atomizer support stands for each atomizer
supplied.
(vi) Provide corrosion and abrasion-resistant materials for atomizer disk.
f) Provide a system with:
(i) Ability to maintain guaranteed SO2 removal requirements during a normal
maintenance atomizer change-out (out of service) for the specified plant
operating conditions.
(ii) Ability to operate continuously
(iii) Provisions for purging of the slurry and air lines to every nozzle assembly
to prevent pluggage, and provisions for low flow switches to alarm a
pluggage condition.
(iv) Provide maintenance access doors or manholes on each SDA vessel.
(v) Provide access doors that are leak tight and conveniently located.
(vi) Provide at the bottom of SDA vessel hopper, a 600 mm by 600 mm
opening.
(vii) Provide SDA hopper heaters (owner’s approved), attached to outer face
of hopper. Design and provide low watt density type heaters adequate to
maintain hopper outside surface at the operating flue gas temperature with
a thermostatic control located at the hopper bottom. Extend heating to the
hopper throat area.
(viii) Provide level detectors to alarm on high hopper level.
(ix) Provide hoppers with valley angles not less than 60 degrees from horizontal.
(x) Shield nuts, bolts, and other fasteners in the flow path from the
a) Provide two parallel (2x100%) lime slaking trains with detention type slakers
sized based on worst case shall be provided.
b) Provide each slaker with size classification and recycle equipment, as
necessary, to produce lime slurry at a rate equal to at least the maximum of lime
consumption rate at 100% TMCR (210MW) load.
c) Design the system to accept the water as per specification.
d) Provide in-line water heaters and pressure regulators, as required.
e) Include provisions to flush and drain the slaker and to maintain all vents clear and
functional. Provide devices to prevent dust and vapour escaping from the slaker,
especially to the lime feeder located upstream of the slaker.
f) Provide solution with sufficient capacity to contain all liquid surges resulting
from slaker start-up and/or shut-down operations. Floor drains discharge to the
area trench and sump system provided by others.
g) Provide a slaker design capable of continuous or intermittent operation.
h) Provide covered inspection/access ports for the slaker. Provide an access port
for sampling lime feed in the inlet housing.
i) Provide all equipment and instrumentation required for automatic control of the
lime slaking system, through the DCS. The controls shall include lime feed,
water feed control, and classification system. Provide sufficient signals for
remotely assess the status of the slaking operation. Provide a pre-wired local
operator panel for the lime storage and slaking system with push- buttons,
switches, and lights, which are I/O to the control system, so control can be local or
remote. This panel interfaces to the DCS.
j) Provide a grit removal and storage system for each slaker that will facilitate
periodic removal of grit, if required. Discharge to the floor is unacceptable.
Design grit disposal system with weather protection, i.e., on a slab and under a
roof. Design for discharge of grit into portable containers.
k) Design the grit removal system to remove grit produced at the maximum
slaker capacity. Provide removable screens of stainless steel, wire mesh type.
l) Provide grit screens of welded heavy construction to avoid screen tearing.
m) Provide internal baffles such that incoming slurry does not impinge directly on grit
screen.
n) Strainers shall be provided.
a) Provide one lime slurry storage tank for slaking train to store slurry equal to 12
hrs consumption. Allow for a minimum of 300 mm free-board space in the tank
sizing criteria.
b) Provide tanks with all necessary internals, nozzles, and attachments.
c) Provide tanks of all-welded construction. Make all welds on tank interior full
penetration seal welds. Skip or stitch welding is not acceptable. Equip shop-
fabricated tanks or tank partial sections for field final assembly with at least four
lifting lugs.
d) Equip tanks with overflow and drain nozzles.
e) Provide manhole for cleaning and waste removal purposes.
f) Provide high and low level detectors and indicators with local and remote
alarm for each tank.
g) Provide tanks capable of isolation for cleanout and maintenance.
h) Additional corrosion allowance of 3 mm on the minimum tank shell thickness as
calculated by IS:803, latest edition shall be provided by the bidder.
i) Interior surface of the tank shall be lined with replaceable chloro-butyl /
bromo-butyl/ rubber lining of minimum 5mm thickness and outside surface shall
be painted as per painting specification.
03.13 Agitators
a) Furnish tanks containing solid slurries with top-mounted agitators. Provide at least
one agitator for each tank.
b) Agitator shall be of reputed manufacturers (approved by owner) have same
application references Provide agitators and supports of heavy-duty, high quality
construction, and complete with motors, gear drives, coupling guards, and
mounting baseplates.
c) Provide each agitator with sufficient mixing energy to maintain all solids in
uniform suspension without solids settling or size separation.
d) Size agitators and drives to provide re-suspension of solids following a
minimum 90-minute period without agitation. Two impellers on one shaft shall be
provided.
e) Design agitators and drives to start up and perform over the full range of tank levels
from overflow to low level.
margins as specified in the respective clauses. The slurry concentration in the pump
shall be as per OEM’s standard technology with similar application.
c) All the slurry pumps shall be provided with motorized suction and discharge
valves. In addition, flushing water lines with motorized valves shall be
provided for each pump for automatic flushing of the pump after each shut down.
The flushing water for the pumps shall be taken from the process water
supply.
d) The pump casing should be radially split to allow easy removal of impeller.
e) All the pump wear parts in contact with the slurry shall be provided with
replaceable rubber/elastomer liners suitable for the fluid handled. The Bidder can
also offer a high chrome alloy lined pump if the Bidder has previous experience of
the same for similar applications. The material used by the bidder shall be proven
in previous installations.
f) The material and thickness of the liners shall ensure a minimum service life of 2
years before replacement. All the wear parts of the pump shall be guaranteed
for a minimum wear life of not less than 14000 hrs.
g) The design of the shaft shall ensure that the operating speed is at least 20% above
the critical speed of the shaft.
h) The pump shall be provided with seals of proven type and shall be designed for
minimization of seal water consumption. The shaft shall be supported on heavy
duty ball/roller bearings.
i) All rotating parts shall be statically balanced. Water & slurry pumps are
balanced per ISO 19401-1:2003 quality grade G 6.3. Water pumps and slurry
pumps have a maximum shaft run out of 0.002 inches.
j) Slurry pump impeller shall be closed type.
k) Bidder to consider minimum margin of 10% on flow and 15% on Frictional
Head.
Table-6.3: Slurry Pump Design
convenient for operation. No drain line shall be sized below 25 mm ID. All drain
lines shall be provided with two isolating globe valves in series.
d) Pipe Size in pump suction side shall be at least one pipe size larger than the
corresponding pump discharge connection.
e) A margin of 10% to be considered on the actual friction drop for arriving at
pump head (considering Hazen-William).
f) Pipes sizing criteria to be considered as follows:
a) Proper approach shall be provided for access to all equipment during normal
operation and maintenance. Unless otherwise specified, platforms, staircase and
ladders shall follow the stipulations specified elsewhere in this specification.
b) Equipment requiring monitoring during regular operation shall be approachable
from the ground floor through staircase. Staircase with minimum width of
a) Wind loads
b) Dead weight including weight of insulation, lining, wash water and the vertical live
load.
c) All ducts to be designed for one tenth of duct full of ash. The ash density for the
purpose of loading shall be at least 1300 kg/m3.
d) Expansion joint reaction.
e) Seismic Load
The following minimum load factors shall be applied to the design load.
Temperature (Deg. C) Load FACTOR
27 1
38 1.02
93 1.12
149 1.19
205 1.25
260 1.29
316 1.34
321 1.42
All ducts shall have a sufficient slope with respect to horizontal so that any chance
of accumulation of ash particles or water in the duct can be avoided under all
normal/abnormal operating conditions. The inlet duct shall be sloped towards the
absorber.
f) The Absorber inlet duct shall be of rectangular cross-section and shall be of all
welded construction.
g) Steel plates for gas ducts shall be minimum 7 mm thick & duct stiffening shall be
by means of rolled sections of duct material.
h) A corrosion allowance of 1.5 mm shall be considered for stress calculation for the
flue gas ducting.
i) Duct stiffening shall be by means of rolled sections. No internal stiffeners shall be
used for ducts from Absorber outlet to chimney inlet.
j) The stiffeners provided on the ducts walls shall be of such a design and layout that
no rainwater can accumulate on the duct surfaces.
k) The flanges at the bolted joints shall have adequate stiffeners to avoid
damages to the flanges.
l) All necessary wall boxes and floor collars shall be provided where the
ductwork pass through walls, floor and roof.
m) The floor collars shall be fitted with a high combing to prevent water and dust
06.00 Noise
a) All the plant, equipment and systems covered under this specification shall perform
continuously without exceeding the noise level of 85 dBA over the entire range of
output and operating frequency.
b) Noise level measurement shall be carried out using applicable and
internationally acceptable standards. The measurement shall be carried out with a
calibrated integrating sound level meter meeting the requirement of IEC 651 or BS
5969 or IS 9779.
c) Sound pressure shall be measured all around the equipment at 1.0 m
horizontally from the nearest surface of any equipment/ machine and at a height of
1.5 m above the floor level in elevation.
d) A minimum of 6 points around each equipment shall be covered for
measurement. Additional measurement points shall be considered based on the
applicable standards and the size of the equipment. The measurement shall be done
with slow response on the A – weighting scale.
minimum:
a) All pipes, valves, steam traps, are to be subjected to hydraulic test as called for
under IS, BS or other approved codes. Copies of certificates covering all the
hydraulic tests shall be submitted to the Owner. The following shop tests shall be
conducted, as applicable according to the approved manufacturer’s test Procedures:
• Material Analysis
• Radiographic test at welds.
• Magnetic particle examination
• Dye penetrate examination
• Hydro static test.
• Dimension check
• Ultrasonic test (as required)
b) Conduct factory performance tests for pump and blowers (one for each type,
minimum) in accordance with HIS and other applicable standard.
c) Perform hydrostatic tests on pressure-containing component of the system at not
less than 150% of design pressure in accordance with applicable code and standard.
d) All pumps and fans are to be tested at manufacturer’s works. Complete
performance tests are to be carried out on each pump/ fan to verify its output (flow)
against total head, power input, efficiency and suction head. Head vs. Volume,
Suction head vs Volume, Volume vs Efficiency and power input curves corrected
for site conditions are to be provided.
e) All booster fans shall be tested at manufacturer’s works as per approved quality
plan. Full range and full-scale performance testing shall be conducted at shop on
one (1) number Booster Fan as per BS EN ISO 5801or AMCA. The performance
testing at shop shall be conducted using actual fan and job motor.
09.00 Site Tests
Bidder shall carry out the tests at site to prove to the Owner that each equipment of
the plant complies with all the requirements specified. Before the plant is put into
commercial operation, the Bidder will be required to conduct tests to demonstrate
to the Owner that each item of the plant is capable of correctly performing the
functions for which it was specified. These tests may be conducted concurrently
with those required under commissioning sequence. The tests required shall
specifically include the following:
• Checks on the operation of dampers including tests of gas tightness/ leak
proofing.
• Check on operation of all fans to ascertain level of noise and vibration.
• Test running of pumps and motors.
• Check free rotation of gas heater and adjust seals, if necessary when heater
is up to working temperature.
• Check operation of all variable speed drives throughout their respective
ranges on lime feeders etc. where applicable.
• Check operation of all motorized isolating valves both locally and from
the FGD control room.
• Check operation of all individual control loops in the FGD control system.
• Check inter-relation between each separate control loops.
• Calibration of instruments before commissioning as required.
• Gas tightness test on FGD system.
• Calibration tests of monitoring, instrumentation and control system/
devices (permanent one) to be used for tests.
• Other tests shall be conducted if required by the Owner to establish that the
plant equipment is in accordance with requirements of specifications.
10.00 Field Operations
After completion of installation of Booster fans, ducts & reactor/absorber for each
unit, and before commencement of application of thermal insulation, a test shall be
performed on the FGD system to prove and to establish the tightness of the erected
equipment. The procedure adopted for such tests shall have the prior approval
of the Owner. Normally physical leak detection method by pressurizing the
section under test by running Temporary blower is adopted. The bidder may adopt
any other better method of testing. All equipment including any temporary
blanking, if required, for the above test shall be provided. The air and gas tightness
test procedure shall be such that it shall enable conductance of air/gas tightness test
on the ducts in segmented manner (as and when these duct segments are ready), so
that these duct segments can be immediately released for application of
insulation after their gas tightness tests. Bidder shall make all necessary
arrangement for conducting tests in this manner. Any blanking etc. on the duct
side required for testing of duct segments shall be provided by Bidder. Bidder
shall bring fan / blower (s) of adequate size / capacity and other necessary
instruments so that these tests can be conducted. The above equipment shall be
brought to site by the Bidder on temporary basis and shall be taken back after
successful completion of air / gas tightness test.
Any other pre-commissioning activity such as floating of safety valves etc. as
considered essential for readiness of facilities for commencement of commissioning
activities shall also be undertaken by the Bidder.
The performance tests of complete installed FGD system shall be carried out in
accordance with ASME PTC 40 (2017) code. The details of the test shall,
however, be mutually agreed upon between the owner and the bidder.
The FGD system shall be stabilized within permitted limits of operation prior to the
test, as specified under PTC 40. Necessary correction curves as per guidelines of
PTC 40 shall be used to compute performance test results in case of variation of
operating parameters from reference performance guarantee conditions.
a) Computational Fluid Dynamics (CFD) modelling for gas flow is essential for the
complete FGD system.
b) The test procedure shall be submitted for Owner’s approval.
c) Bidder shall provide within the scope of supply, flow modelling to verify the
flue gas path design from the ID Fan outlet to the stack (within the terminal point),
using physical model.
d) The Bidder shall provide as implosion modelling study to be performed to
determine flue gas system design pressure is adequate.
e) Include three-dimension scale model of the FGD absorber (include inlet transition)
and interconnecting flue work. Conduct test to determine:
(i) The size, configuration and location of all the necessary gas
distribution devices.
(ii) Final configuration of flue work.
(iii) Appx. Pressure drop through the system.
(iv) Gas flow distribution in the absorber.
(v) Adequacy of the draining.
f) Modelling shall also be performed on the wet/dry interface of the absorber inlet
duct.
g) The model shall address gas flows for the range of full load conditions from
minimum load flow to max design gas flow across the full range of fuels.
h) Bidder to give at least 30 working days advance notice to witness the model test.
i) Provide scale factor of model to prototype, test procedures and description of test
instrumentation to owner for review and written permission to proceed. Scale
factor shall be not less than 1:12.
j) Provide a complete model test report describing configuration tested,
recommendations and test results for each such configuration.
k) Obtain inlet flue velocity profiles and outlet flue velocity profile from a model
for 100% flow. Express and tabulate these velocities in the cross-section. Provide
vanes to limit fan inlet velocity/ volume readings to ±5% side to side.
l) Record inlet flue velocity profiles and outlet flue velocity profile on model for
100% flow.
13.00 Buildings
a) Bidder shall consider buildings for air compressor/air dryer, water pumps, slurry
pumps, hydrated lime preparation /lime slurry preparation building (as per
bidder’s technology) and FGD control cum electrical room. The buildings must be
complete in all respects specially facilitating the smooth operation and
maintenance of associated equipment of above systems by providing adequate
maintenance space, handling facilities, walkways, staircase etc.
b) Bidder shall consider corrosion protection painting for structures &
equipment as described in the specification.
c) All platforms, walkways, staircase, safety rails for access to each equipment,
valves, dampers, gates, instruments etc. handling facilities for each component of
FGD system shall be included for the building structures.
02.01 Technical particulars are to be filled up in this tender document or mentioned elsewhere in
other Volumes of , shall be valid for all makes proposed by bidder and shall not be altered
later by the bidder due to selection/ finalization of any sub-contractor by the bidder.
02.03 The bidder shall ensure that all information, data performance curves, technical literature
(catalogues) and drawings furnished here and during detailed engineering fully describe all
equipment/ systems covered under this tender document and fully meet the requirements of
the present scope of work.
02.04 The purchaser reserves the right to ask for future details regarding technical features,
application particulars, performance, past experience for similar application or any other
information as may be required to fully satisfy himself regarding suitability, quality,
reliability and full compliance with this specification for all equipment and systems offered
by the bidder.
02.05 It may be noted that this technical data sheets section is for bidding purpose only. During
detailed engineering, the bidder will be required to furnish all additional data about the
equipment/ system being supplied, even if such details are not asked for this section. The
details furnished in the data sheets are preliminary and may be subjected to changes during
detailed engineering stage. However the requirements of TANGEDCO tender specification
and the agreements reached during the techno-commercial discussion and price negotiation
meetings will be met with.
02.06 General Technical Information / Data Drawings for Flue Gas Desulphurization
System (Separate for Each Unit)
vi) General
Arrangement/Outline
Drawings
• Dimension and Location
(plan & elevation) of all
equipment including
dimension.
• Maintenance area
requirement.
• GA (Plan & elevation) of
FGD Plant
• FGD Plant control room
(plan & elevation) details
vii) Auxiliary Power
Requirement of each
equipment
viii) Flue gas ducting
arrangement drawing
9 Sealing Efficiency with Seal % 100% leak tight
air fan
10 Seal Air Fan Flow / Head (m3/h/m
mwc)
11 Heater type provided
2 Size (m x m)
1 Manufacturer
TENDER SPECIFICATION
FOR
SEMI DRY FLUE GAS DESULPHURIZATION
(FGD) SYSTEM & ITS AUXILIARIES
VOLUME – IIC
BALANCE OF PLANT
MECON LIMITED
RANCHI – 834 002
INDEX TO VOLUMES
Volumes Title
Volume – I Commercial
Volume – II Technical
Volume - IIA General Technical Specification
Section 01.00 Preamble
Section 02.00 Intent of specification
Section 03.00 Project information
Section 04.00 Special instructions to Bidder
Section 05.00 Scope of work, supply & Services
Section 06.00 Quality Assurance system / Requirement
Section 07.00 Painting
Section 08.00 Finalization of sub-vendors / sub-contractors
Section 09.00 Performance Guarantees
Section 10.00 Terminal points & Exclusion
Section 11.00 Layout and maintenance requirement
Section 12.00 Drawings / Documents to be submitted along with Bid / Offer
and after award of contract
Volume -IIB Technical Specification
Section 01.00 Flue Gas Desulphurization System
Section 02.00 Technical Data Sheets – Mechanical
Volume -IIC Balance of Plant (BOP)
Section 01.00 Water Supply Facilities System
Section 02.00 Air conditioning & Ventilation System
Section 03.00 Elevators, Cranes & Hoists
Section 04.00 Fire Protection System
Section 05.00 Piping, Valves & Fittings
Section 06.00 Thermal Insulation, Lagging, Cladding
Section 07.00 Compressed Air System
Volumes Title
Volume - III Instrumentation & Control System
Volume -IV Electrical System
Volume -V Civil, Architectural & Structural Works
Volume -VA Civil Works
Volume -VB Architectural Works
Volume -VC Structural Works
Volume -VI Mandatory Spares and Tools & Tackles
Volume -VII Tender Drawings
Water System Facilities: Water system shall in general include the following
facilities for 4 nos. of FGD (Flue gas de-sulphurisation) system:
Process water (industrial grade) is for the consumptive water use of FGD system.
Process water for FGD system shall be tapped off from existing clarified water
network with an isolation valve and valve pit. For detailed TOP refer VOL-IIA/
Section 10.00
i) One number process water storage tank /FGD unit of 4 hours capacity has been
envisaged for each unit
ii) 02 nos. of process water pumps one working and one standby have been
envisaged for spray purpose of each unit
iii) Complete piping, fittings, supports, valves, instruments etc. will be provided.
Each FGD system shall be having separate dedicated closed cooling water system
using DM water. Cooling water system shall consist of primary and secondary
circuits. Primary circuit shall be using DM water and secondary circuit shall be
using industrial quality water. For
secondary circuit, cooling supply water shall be tapped from existing auxiliary
cooling water (ACW) supply of each unit. Return water line from secondary
circuit shall be connected to existing hot water return header of that unit. DM
water re-circulating water pump sets (1 working+1 stand-by), plate heat
exchangers (1 working+1 stand-by), expansion tanks (MSRL), SS piping and
associated appurtenance etc. shall be envisaged for primary cooling water circuits
of each FGD system. DM water shall be tapped from the existing DM water
network with an isolation valve. Each tapping of ACW shall be from existing
corresponding ACW network with an isolation valve. For detailed TOP for both,
refer VOL-IIA/ Section 10.00.
Industrial water shall be required to meet the make-up water requirement of each
FGD system. This shall be common for all the FGD system. Make up water shall
be provided for the following:
i) Water tank . The capacity of service water tank shall be of approx. 1 hr.
ii) Air conditioning and ventilation system
iii) Process area viz, booster fan area, silo area, absorber area, etc.
iv) Miscellaneous water requirement viz. Plant washing, gardening etc.
In this circuit two pump sets (1W+1S) along with required associated
appurtenances shall be considered of adequate capacity & head to meet the
requirement.
Service water shall be tapped from nearby service water network with an isolation
valve and valve pit. For detailed TOP refer VOL-IIA/ Section 10.00.
Portable water is required to meet the drinking water needs of plant personnel.
Portable water shall be tapped from existing portable water network with an
isolation valve & valve pit. For detailed TOP refer VOL-IIA/ Section 10.00.
Drinking water system shall be designed based on 30 persons/ shift catering two
different area having distance of approximately 500 meter.
e) Fire Water
Fire Water shall be tapped from existing fire header available at plant with an
isolation valve & valve pit. For detailed TOP refer VOL-IIA/ Section 10.00.
External hydrants will be Landing Valve type with single outlet 63 mm size as per
IS : 5290 Type A. Internal hydrant will be single outlet 63 mm size with
instantaneous female coupling as per IS : 5290 Type A.
Hoses:
(i) 2 nos. of 7.5 m long hose (RRL) as per IS: 636 shall be provided for each Landing
valves along with fittings.
(ii) 2 No. of 15m long hose (RRL) as per IS: 636 shall be Provided for each External
hydrant.
These will be kept in hose box (fabric reinforced plastic) along with branch pipe,
nozzle (20 mm bore size), spanner etc.
Note:
1. All the hydrant valves, branch pipe, nozzles shall be of Stainless Steel.
f) Interplant Pipelines
Process water, Cooling water, Portable water &Service water network and fire
water network will be provided to various consumption points in the proposed
FGD plant. All the water lines including fire water, drinking water, will generally
be laid over-ground outside the buildings and on building columns inside the
buildings.
Cooling water pipes, Make-up water pipes, drinking water pipes and fire water
pipes shall be generally laid over- ground.
Make-up, fire and auxiliary cooling water pipes shall be of carbon steel with
beveled ends and drinking water pipes shall be of galvanized iron with threaded
ends & DM water pipes shall be of stainless steel (304L) with bevel ends.
Piping system shall be designed with high degree of reliability so that the systems
perform the duty of fluid handling without any failure under all conditions of plant
operation.
Piping layout must follow good engineering practice. Proper attention shall be
given to obtain full functional requirement of the piping system with a layout
which provides sufficient clearance for other equipment and operating personnel,
easy access for operation and maintenance, convenient supporting points and neat
appearance.
The design shall take into account the effect of internal/external pressure, thermal
expansion, self weight of piping, support reactions, surge and water hammer,
earthquake and wind effects at site, corrosion and erosion etc. and any other
effects dictated by good engineering practices.
As far as possible all the pipelines shall be laid together along the piping corridor.
The piping corridor shall be parallel to and by the side of roads.
All pipes network shall be provided with manually operated valves for
isolation/controlling purpose. Valves for size 125 mm and above shall be gear
operated and valves of size above 450 mm shall be electrically operated.
The pipe network shall be provided with air release valves at high points and drain
valves at the lower points.
Valves provided on the over-ground pipe network shall be provided with steel
structural platforms and access ladders.
Pipe supports shall be capable of supporting the pipelines under all conditions of
operation.
Pipelines shall be generally laid over ground on the structural trestles as far as
possible, wherever it is not possible pipelines shall be laid in tunnels
/trenches/underground in this order of preference. All openings in the piping
shall be kept effectively closed until assembled in the system to avoid
foreign matter entering into the system.
Valves provided on the over-ground pipe network shall be provided with steel
structural platforms and access ladders.
As far as possible all the pipelines shall be laid together along the piping
corridor. The piping corridor shall be parallel to and by the side of roads.
Wherever over-ground pipelines are crossing roads and railway tracks, they
shall be laid on pipe bridges to provide the necessary clearance for the traffic
movement. This should take in to account the various type of vehicles likely to
move in the plant.
All the buried pipelines shall be laid with a nominal slope towards the drain point.
All the buried pipelines shall be laid as far as possible at a depth of about 1200
mm, below finished ground level (i.e. the top of the pipelines shall be 1.2 m below
the finished ground level).
Vol. – IIC, Section 01.00 WATER SUPPLY FACILITIES Page 6 of 42
© 2020 MECON Limited. All rights reserved.
TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION- I (4X210MW)
Isolation /control valves drain valves, air release valve provided on the buried pipe
network shall be housed in suitably sized covered valve pit and the valve pits shall
be of self draining type.
Wherever the buried pipelines are crossing the roads and tracks, they shall be
suitably encased with mild steel pipes or reinforced concrete casing pipes and the
different sizes of the encasing pipes shall be as given below:
In case a number of pipes are crossing road or track, these pipes shall be laid in a
reinforced concrete culvert having easy access.
Coal tar based anticorrosion tape as per IS: 15337 – 2003 shall be provided for
protection of underground mild steel pipelines. The thickness of tapes shall be 3
mm upto pipe diameter DN 300 mm and 4 mm above pipe diameter of DN 300
mm.
All buried pipelines shall be laid with earth cover sufficient to avoid damage from
pressure of vibration caused by the surface traffic. Minimum earth covering over
the pipe shall be 1200 mm from the finished ground levels. For laying of buried
pipelines earth work in excavation, back filling and acceptance of trenches etc.
shall be as per IS: 5822-1994 and IS: 3114-1994 and IS: 12288-1987.
The trench shall be so dug that the pipe line can be laid to the required alignment
and at the required depth, proper leveling of the excavated surfaces is an essential
requirement.
In case stones, boulders etc. are found at the bottom of the trench which cannot be
removed completely, the bottom shall be leveled by sand layer for a minimum
thickness of 150 mm.
If the depth of excavation is more, proper protection for side walls shall be
provided till the pipe leveling is completed.
The entire pipe trenches bottom shall be covered with local sand bed of 50 mm
thick layer.
After laying the pipelines, 150 mm thick layer of local sand shall be provided over
the sand bed.
Precautions shall be taken at all the times to prevent damage to the coating and
wrapping in the pipe lines and appurtenances as applicable by workmen or
trespassers during laying or at any other time. Pipe handling slung and any
blocking used in handling or storing the pipes must be well padded to avoid
damage to pipe and its coating.
After laying a pipeline on skids it shall be thoroughly cleaned, inspected and for
any damage to the protective coating, satisfactory repair work shall be performed
while the pipe is suspended above the trench.
Before laying the pipelines, the trenches shall be examined by the Owner and after
his approval only the pipes can be laid.
After the pipes are erected and tested, the back filling of the trenches shall be done
with loose soil free from stones, bricks and metallic pieces, in layers and shall be
well rammed and compacted.
RCC manholes with removable covers shall be provided for the buried gravity
network and the maximum distance between two manholes shall be 30 to 50 m
depending upon the pipe size. Manholes of adequate size shall be provided at all
pipe junctions.
Where the pipelines cannot be laid overhead on stockades and are crossing roads
and tracks at too many points in a given area, the pipeline may be laid in walk-
able tunnels.
Pipelines in tunnels shall be provided with isolating valves, air release valves and
drain valves, which are easily accessible for operation and maintenance. Gland
type of Compensators shall be provided on these pipelines wherever necessary.
two vertical centrifugal, non-clog type drainage pumps (one working and one
standby) and these pumps shall operate automatically based on the liquid levels.
Each tunnel shall be provided with at least a monorail and hoist for erection and
maintenance purposes. Minimum height of the tunnel shall be of 2.2 m and
suitable walkway shall be provided for each tunnel.
Pipelines within the shop buildings shall be laid overhead supported form the
building columns/side walls/cranes girder etc. wherever this is not possible, the
pipelines shall be laid either in tunnel or in pipe trenches (covered with removable
slabs of chequered plates).
Wherever pipelines are crossing form one bay to another parallel bay, they shall
be laid in tunnel or supported from the gable end.
Nominal pipe size (mm) Maximum span for liquid services (m)
25 2.1
40 2.7
50 3.0
65 3.4
80 4.0
100 4.3
150 5.2
200 5.8
250 6.7
300 7.0
350 7.6
400 8.2
450 8.5
500 9.2
600 9.8
900 12.0
1000 15.0
Note: Vertical pipe work shall be clamped at intervals of 3.5m (approx.) and at
the base of each riser. Maximum span at the place of turning shall be 0.7 times of
normal span.
Tolerance on outside diameter of the pipe and specified thickness shall conform to
the limits laid down in IS:3589-2001. Finish pipe shall not deviate from
straightness by more than 0.2% of the total length.
Welding procedures shall be prepared in line with IS: 7307 (Part – I) – 1974,
reaffirmed in 1991 and tests shall be carried out to quality procedures. Number of
procedures will depend on variables like positions of welding, thickness range etc.
Once a welding procedure is qualified, strict adherence to it shall be made during
actual welding.
Welders employed shall be qualified as per IS: 7310 (Part – I) – 1974, reaffirmed
in 1987 after passing necessary tests.
The Contractor shall strictly follow approved welding procedures during actual
welding. Besides, the following stages of inspection shall also be carried out:
Weld edge preparation before welding, proper fit up, position of welding, cleaning
of slag between the passes, proper weld profile etc., shall be checked visually
amongst others.
Non-destructive tests of weld of welded joints shall be carried out as per approved
procedures/ drawings.
Preparation of Joints
The Contractor shall prepare the edge correctly to the shape, size and dimensions
of the vee-grooves as per ANSI B-16.25 unless otherwise specified in drawings/
documents.
The welding surfaces shall be smooth, uniform and free from fins, tears, notches
or any other defect which may adversely affect welding and shall be free from
loose scale, slag, rust, grease, paint, moisture or any other foreign material. The
clean surface shall extend to about 10 mm beyond the welding faces to avoid
contamination of the weld metal with foreign material and to avoid unsound weld
deposit.
The sequence of welding shall be so planned and followed that there shall be a
balance of welding about the neutral axis of the fabrication. The Contractor shall
employ sufficient number of welders working at the same time in diagonal
quadrants of the shell using back-step method of welding. The rate of progress of
each welder shall be more or less equal and quality uniform.
The general direction of welding shall be towards the free end of the joint, but in a
long joint as in shell fabrication, back-step technique shall be used to reduce
distortion.
To minimize internal locked up stresses due to welding, the vertical joints for the
shell shall be welded and completed to a circular course and then the horizontal
circumferential seam welded. However, before the welding of horizontal seam
started, the complete circular course shall be aligned and adjusted for their correct
axes.
Alternatively, the Contractor shall complete each course in all respect on ground
and then the pre-assembled course shall be listed and placed in position. In such a
sequence and planning, the same principle of balancing of weld about the neutral
axis shall be followed and the method of fabrication of each course shall be
similar to fabrication of penstock pipes of transmission/ industrial pipelines of
bigger diameter.
Pipe and attachment shall be aligned properly by accurate and permanent methods
prior to welding. If tack welds are used, the tack shall be either fused into the first
layer or weld or else chipped out.
Visual examination
Influx
Vol. – IIC, Section 01.00 WATER SUPPLY FACILITIES Page 12 of 42
© 2020 MECON Limited. All rights reserved.
TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION- I (4X210MW)
Burns
Under cuts
Unwelded crates
The Contractor shall carryout any or all tests as specified hereinafter to satisfy the
Purchaser about the acceptability of the welded joints, as directed by the
Purchaser.
Liquid dye-penetrant tests shall be carried out in accordance with IS: 3658-1981,
reaffirmed in 1991 for surface/ sub-surface defects.
Test by Blowing
The surface of the weld shall be covered with soap solution consisting of one (1)
litre of water and hundred (100) grammes of soap. Compressed air shall be blown
from the opposite side at pressure of 4 to 5 kg/cm2. The distance between the tip
of base and the weld shall not be more than 50 mm. Any formation of soap bubble
will indicate welding defects. Portable compressor shall be arranged by the
Contractor, if necessary, for this purpose.
Tolerance
Tolerance
Sl.
No. Manual arc Automatic
a) Source butt-Joints
i) Gap between the ends of + 2.00 mm ± 1.00 mm
plates - 1.00 mm
1.00 mm 2.00 mm
ii) Stepping of one plate
over the other
b) Single Vee-groove Joints
i) Bevel angle ± 5 deg. ± 5 deg.
ii) Gap between two + 2.00 mm + 1.00 mm
- 1.00 mm
iii) Stepping of one plate 2.00 mm 2.00 mm
over other
c) Lap Joint
i) Overlap 5.00 mm 5.00 mm
ii) Gap between the surface 2.00 mm 1.00 mm
d) Tee-filler Joints
i) Gap between the edges of 2.00 mm 2.00 mm
the web and the surface of
the flange
01.03.04 Pumps
The pumps and their auxiliary equipment shall be suitable for the required duty
conditions and shall be designed and constructed for continuous duty at full load.
The centrifugal pumps shall be suitable for a capacity range of 25% to 125% of
duty point capacity.
The motor capacity shall have a margin over its BHP absorbed at the pump shaft
at duty point and the margin shall be 25% for motors of rating upto 15kW, 20%
for motors of rating 18.5kW to 160kW and 15% for motors of rating 200kW and
above.
The equipment and auxiliaries shall be designed for quick and economical
maintenance. The equipment shall be easily dismantable without disturbing the
suction and delivery pipe connections.
The equipment design shall incorporate provisions for reduction in noise level.
The rotating elements of the pumps shall be checked for critical speed in bending
as well as torsion. The critical speeds shall be at least 30% away from the normal
speeds for units with flexible shafts and at least 20% away from the maximum
operating speed in case of stiff shafts.
All passages inside the pump casing and impellers, which may be inaccessible to
machining shall be ground to a smooth finish as far as practicable.
The pump shall be so selected and installed that the available NPSH is not lower
than the required NPSH even in the most adverse operating conditions.
The pump shall be of proven make and design having material of construction
which is the best of its kind for the particular application and shall be
manufactured using best engineering practices under strict quality control. Each
pump shall be tested as per the standards stipulated elsewhere in this document.
The test shall include hydrostatic test, static and dynamic balancing tests,
performance tests material tests and motor routine tests.
The pump shaft and bearing shall be adequately sized to take the unbalanced
forced due to mal-operation. The pump gland shall ensure proper sealing without
excessive tightening of the packing. Proper cooling and flushing arrangement for
the gland shall be provided wherever required.
All moving parts of the pump shall be adequately guarded to prevent any injury to
operating personnel.
Pumps shall be designed and installed keeping in view the easy accessibility of its
parts for maintenance. All end suction pumps shall be of back-pull-out design and
shall be provided with spacer coupling of adequate length.
Mechanical seals shall be provided at all pumps envisaged for closed loop circuit.
Minimum no. of standby pump shall be provided for each group of clear water
pumps and drainage pumps as specified in the design criteria for pump house. The
group of Pumps for scale water or other abrasive slurries shall be provided with at
least two standby units. Special abrasion resistant material shall be used for these
pumps and the design shall allow easy replacement of parts subject to wear and
tear.
An isolating valve shall be provided on the suction line of each pump and another
isolating valve together with a non-return valve shall be provided at the delivery
line of each pump. Pressure gauges shall be provided at the suction and delivery
flange of each pump.
The suction pipeline shall be laid at a constant down ward slope from pump centre
line to the suction chamber. Reducers used in the line shall be eccentric type to
keep the top of the suction line straight.
Each pump shall be provided with adequate safety interlocks including overload
and dry running protection.
Dismantling joints shall be provided on the delivery side of large size pumps to
facilitate quick maintenance, wherever required.
All pumps shall be provided with suitable lifting attachments and each pump
installation shall have suitable handling facilities.
A clear minimum gap of 700 mm shall be maintained between the pump and the
adjacent piping, other equipment or structures for proper movement. In case the
height of the top most part of the pump from the working floor is more than 1.0 m,
the minimum clearance shall be increased to 1000 mm.
The details of pumps should match with the drive motors throughout the working
life of these equipments and to meet operational requirement. High-speed motors
of 3000 rpm shall not be used, as for as practicable. Working hour meter shall be
provided on control panels to monitor conditions and subsequent ageing / reduced
efficiency, etc.
The impellers along with any other unmachined rotating parts shall be tested for
proper balancing in order to avoid undue vibration during operation.
The discharge against a specified head when running at a specified speed under a
specific suction head.
The power absorbed by the pump at the shaft (BHP) under the above-specified
conditions.
The pump accessories like bearings, couplings etc. shall be subject to shop tests as
per manufacturer’s standards.
All test results and certificates including material test certificates shall be
submitted for approval to the purchaser before dispatch of equipment.
The vertical centrifugal pump sets shall be supplied with flange mounted vertical
motors, motor stool, base plate, coupling, column pipe, delivery pipe, suction
strainer, companion flanges, gaskets, bolts, nuts, washers, etc.
A stainless steel name plate shall be furnished and securely attached by stainless
steel pins at an easily accessible point on the pump. The plate shall be stamped
with the following minimum information: -
- Name of Manufacturer
- Model No.
- Motor rating, kW
A) Horizontal Pumps:
8. Material of Construction
Casing Cast Steel , ASTM A 216 WCB
Impeller CF8M
Wear plate / LTB5
liners wear
rings
Shaft SS-410
Shaft Sleeve SS-410
Base Plate MS fabricated
Companion MS
flanges
9. Shut
\ off head Minimum 10
% above duty head.
10. Type of Mechanical packing in case of DM water &
packing Gland packing in case of IW/PW/FW
The above MOC is for guidance, MOC of all pumps will be subjected to
Purchaser’s / Consultant’s approval during detailed engineering.
(a) Bowl
(b) Suction bell
(c) Discharge head
(d) Column pipe
Performance test shall be conducted on each pump with one of the actual drive
motors at the manufacturer’s works in presence of Purchaser’s representative as
per the requirements of the relevant test codes.
Performance tests shall be conducted at rated r.p.m. to cover the entire range of
operation of the pumps. These shall at least cover the range from shut-off point
upto 1.3 times the rated capacity of pumps. A minimum of 5 readings shall be
taken for capacity Vs Head, covering the above range. After performance test, the
pump shall be dismantled for inspection of internal components.
Mechanical run test shall be carried on all pumps to demonstrate smooth running
of the pumps, measurement of noise levels, vibration, etc. This test shall be
carried out at site also and the site test shall be taken for acceptance of the pump.
The noise lever shall not exceed 85 dB at 1.6 m distance from the pump of as per
the latest norm whichever is less.
The pumps shall be tested for vibration at the guarantee points. Vibration limit
shall be as per Hydraulic Institute Standard/ API 610.
All the pumps shall be subject to stage inspection by the Contractor’s own
inspecting authority. However, Purchaser’s Inspector may visit the works from
time to time who should have free access to all the places of the manufacturing
premises where any part/ parts are under manufacture.
01.03.05 Valves:
Flow control /isolating valves, drain valves, air release valves and
Compensators, wherever necessary, shall be provided for the complete in-shop
pipe network.
All valves shall be suitable for service conditions i.e. quality of fluid, flow
temperature and pressure under which they are required to operate.
Valves shall be provided on pipe network for isolation of pipe section and
equipment, control of pressure and flow, venting, draining etc. They shall be
suitable located considering ease of operation and maintenance.
All valves shall be provided with hand wheel and position indictor. The face of
each hand wheel shall be clearly marked with words “Open” and “Shut” with
arrows adjacent to indicate the direction of rotation.
Valves shall be provided with suitable extension spindle and head stock
assembly wherever required. In case gears or bevel system are used , these
shall be of cast steel or suitable grade cast iron with machine cut teeth.
Non-return valves shall be Dual Plate zip check type and shall have a
permanent “Arrow” inscription on its body to indicate direction of flow.
Larger size valves shall be provided with by pass and drain arrangement.
Float operated valve shall be preferably be right angled pattern complete with
ball float, level and other accessories.
Butterfly valves shall be of quotable flanged, tight shut of design with angular
travel of 90 deg. from open to shut off position.
The specification given below is for general guidance for selection of valves.
Final selection shall be subject to purchaser’s / Consultant’s approval.
7 Bolting, internal SS
14 Service Water
15 Max. operating 60
temp Deg 0C
a) Pneumatic Actuators shall be of double acting type for on/off operation and shall
be directly mounted on the valve. Single acting type shall be considered for
fail/safe operation
SS tubing of 3.00 m length along with isolation valve and suitable end
connections for connecting it to ½” MS pipe by welding complete with required
pneumatic tube fittings for connection to dump valve and ½” MS Pipe.
Actuator shall be capable of operating the valve when the air pressure is 6 Kg/cm2
and shall be able to operate the valve even when the air pressure drops to 4.5
Kg/cm2.
Each actuator shall be supplied complete with two or one way solenoid valves of
¼” pipe size. Material of construction for body shall be Brass.
Solenoids for all solenoid operated valves shall be suitable for 20 to 240V AC/DC
Vol. – IIC, Section 01.00 WATER SUPPLY FACILITIES Page 24 of 42
© 2020 MECON Limited. All rights reserved.
TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION- I (4X210MW)
For termination of cable to the solenoid, proximity switches junction box shall be
provided by supplier. Terminals shall be suitable for terminating 2.5 sq. mm
copper conductors. 20% spare terminals shall be provided in the junction box.
Apart from other tests, performance test for pneumatically operated valves with
respective actuators mounted in position to show valves opening and closing and
observation of leakage shall be conducted.
Air release valves shall be cast iron, single large orifice type, with flanged ends.
Air release valve shall conform to IS: 14845-2000.
1 MAKE ROTORK/AUMA/LIMITORQUE/
APPROVED
2 OUTPUTMOTION ROTARY
3 OPERATION TIME 90 SEC (MAX)
4 SERVICE INLET PR.-8.5 Kg/cm2 (MAX)/ as per System
CONDITION requirement
INLET TEMP.-40 deg.C max.
FLUID – WATER
Vol. – IIC, Section 01.00 WATER SUPPLY FACILITIES Page 26 of 42
© 2020 MECON Limited. All rights reserved.
TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION- I (4X210MW)
H) Motor Specifications
Duplex arrangement with built-in valves shall be such that one element will
always remain in operation ensuring continuous uninterrupted supply of filtered
water from each strainer. It should not be possible to isolate both the strainers
simultaneously due to even inadvertent rotation of hand wheels for movement of
valve disc during change over from one basket to another. The changeover valves
shall be manual.
Basket Filter bodies and internals shall be designed to withstand design pressure
with normal surges.
Pressure equalizing connections for both the chambers shall be provided for
smooth changeover.
Two nos. dial type pressure gauges size 150 mm dia shall be provided suitably
mounted at the inlet and outlet mains of each filter with 1.0% accuracy and 3 way
gauge cock. This will be purchased separately and not included in the scope of the
tenderer.
Differential pressure switch with alarm contacts shall be provided for filter unit of
the main strainer across inlet and outlet for operation at a differential pressure
adjustable within 0-1 kg/cm2.
be provided with 3-valve manifold. The dead band shall not exceed 60% of gap
between set value and normal operating value. This will be purchased separately
and not included in the scope of the tenderer.
Flush drain valve and vent shall be provided for each unit of the main filter. The
design of the filter shall be suitable for easy maintenance and replacement of the
parts and inspection.
Strainer shall be provided with basket opening area (six times of pipe cross
section area or bigger) to ensure high flow volumes at low pressure and a long
service life.
Provision shall be made for collection of drainage water from the strainers and
shall be suitably connected to the plant area drainage system.
Along with the offer the Tenderer shall furnish details of the basket filter such as
make, general arrangement and cross-sectional drawings, operating parameters,
materials of construction of various components supported by manufacturer's
literature and catalogues.
Carbon steel Valves to be supplied as part of the duplex filters shall conform to
the following standards. Pressure rating of all valves shall be 16kg/cm2.
The heat exchanger unit shall consist of gasketed plates supported in frame
capable of being opened and closed. The frame provides structural support as well
as pressure containment for the gasketed plates and consists of frame plate,
pressure plate, guide bar, & carrying bars, closing studs/nuts and carrying bar
supporting columns.
The frame shall be designed to permit future installation of 30% additional plates.
Individual channel plates of heat exchanger shall have to pressed / formed in
single mechanical operation.
Each plate heat exchanger shall be designed for full pressure in each stream
having no pressure on other stream.
The heat transfer coefficient in clean condition should not exceed 6500
K.cal/m2.hr.degC
While designing heat exchange area and number of plates, cleanliness factor on
account of fouling shall be considered as 20%.
Carbon steel components in contact with fluid system shall have a corrosion
allowance of min 3mm. All the threaded hardware items like studs and nuts shall
be zinc coated.
The heat transfer area per plate should not exceed 85% of the total plate area.
Frame plate is the primary stationary end of the plate heat exchanger. All nozzles
shall be located on frame plate.
Inspection openings shall be provided on the pressure plates. These openings shall
be blanked by providing blind flanges. Ball valves shall be provided on the
bottom blind flanges for drain purposes. Handles are to be provided on all the
blind flanges.
All nozzles on the frame plate and inspection openings on pressure plate shall be
provided with stainless steel sheet lining conforming to AISI 316.
Pressure plate shall be supported in a roller bearing hanger from the carrying bar.
Pressure plate shall move along the carrying bar and shall be guided by the
guidebar.
The carrying bar shall be welded /bolted to the frame plate and carrying bar
support column. A stainless steel tee section shall be welded /bolted to the
carrying bar to provide mounting member for the plates of the plate pack. A
smooth surface shall be provided for roller bearing carrying grove for the whole
length of the carrying bar. Carrying bar shall be designed to support 1.5 times the
weight of the flooded exchanger along with pressure plate, tie rods, nuts and
nozzles.
Guide bar shall be welded /bolted to the frame plate and carrying bar supporting
column. It shall be sheathed in stainless steel on the 3 surfaces coming in contact
with the plates and is a guide bar only for the plates.
The heat exchangers shall be designed, manufactured and tested as per ASME
code Section VIII, Div. 1 and shall be suitable for the duty conditions and
capacities as indicated in the Annexure-I .
The plate heat exchangers along with their auxiliary equipment shall be suitable
for the required duty conditions and shall be designed and constructed for
continuous duty.
The equipment and auxiliaries shall be designed for quick and economical
maintenance. The equipment shall be easily dismantle without disturbing the
inlet and outlet pipe connections.
A stainless steel name plate shall be furnished and securely attached by stainless
steel pins at an easily accessible point on each plate heat exchanger. The plate
shall be stamped with the following minimum information:-
Capacity in cubic meters per hour both for primary & secondary sides.
Design code.
Dimensional checking
Vol. – IIC, Section 01.00 WATER SUPPLY FACILITIES Page 31 of 42
© 2020 MECON Limited. All rights reserved.
TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION- I (4X210MW)
Hydrostatic tests
Ultrasonic test for the plates used for frame and pressure plates.
All the plate heat exchangers shall be subject to stage inspection by the successful
Tenderer's own inspecting authority. However, Purchaser's Inspector may visit the
works from time to time who shall have free access to all the places of the
manufacturing premises where any part/parts are under manufacturer.
Before giving call for final inspection, all the documents shall be furnished to the
Purchaser. The record of manufacturing details, inspection and tests carried out
by the successful Tenderer shall be made available to the final Inspecting
Authority. However, approval and final inspection at the manufacturing works
shall not relieve the successful Tenderer of responsibility of replacing at his cost
any defective part/material which may be detected by the purchaser during
erection and commissioning or guarantee period.
Hydrostatic test shall be carried out at 1.5 times the design pressure maintaining
test pressure for a minimum of 60 minutes. Testing shall be done by pressurising
each side separately.
The final tests shall be conducted in the presence of the Purchaser's representative.
Test certificates for different tests shall be made available to the Purchaser.
Material test certificates for bought out items shall be obtained from original
manufacturer/reputed test house. For all bought out items, test certificates as
relevant to the items shall be furnished by the successful Tenderer before the
equipment is offered for final inspection.
Wherever required, all tests shall be done as per relevant Indian Standards. In the
absence of the Indian Standard, the equivalent internationally reputed standards
shall be followed.
Painting
Surface of the heat exchanger frame work shall be cleaned to near white metal
conforming to Sa 2 1/2 of Swedish Std. SIS 055900 or German Std DIN 55928
(Part-4)
After surface preparation, the plate heat exchanger shall be painted as per the
manufacturer’s standard.
Vol. – IIC, Section 01.00 WATER SUPPLY FACILITIES Page 32 of 42
© 2020 MECON Limited. All rights reserved.
TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION- I (4X210MW)
Acceptance Tests
Guarantee
All equipment shall be guaranteed for good workmanship, no material defect and
the design parameters till a period of 12 months from the date of successful
commissioning or 18 months from the date of despatch whichever is later.
The successful Tenderer shall stand guarantee that the heat exchanger shall cool
the required quantity of primary water with the specified quantity of secondary
water to the temperatures stipulated in Annexure A of this technical schedule. The
successful Tenderer shall also guarantee the agreed pressure drops across the
primary & secondary sides of heat exchanger. In addition, all items of the heat
exchanger are to be guaranteed in respect of material and workmanship. Any
defects found during warranty period shall be rectified to the complete satisfaction
of the purchaser at the successful Tenderer's cost.
The following codes shall be referred during the fabrication of pressure vessels
and tanks.
Boiler and pressure : ASME SECTION VIII DIV.1 Vessel Code
Welding : ASME SECTION IX
Pipe Flanges : ANSI B 16.5
NACE Standard : MR 01-75 (Latest Edition)
Tenderer shall furnish the capacity and design calculations for thickness of all
major components like shell, head, nozzles etc. for approval prior to
manufacture/fabrication. In case of any alteration in material or thickness,
Contractor shall seek Purchaser’s written approval. For CS vessels, the shell or
head thickness exclusive of C.A. shall be taken, even if pressure/ load
requirements may suggest lower thickness. Non pressure carbon steel parts (e.g.
Skirt, lugs, Cleats, etc.) shall have a provision of 1.5 mm corrosion allowance.
Plates shall be bent along the direction of plate rolling for forming the cylindrical
components of vessel. Plates shall have only positive tolerances on thickness.
Carbon content of C.S plate shall not exceed 0.25%. One product analysis per
heat shall be supplied.
All vertical & horizontal vessels shall be provided with lifting lugs.
All pressure vessels weld joints of category A and B shall be welded with full
penetration and full fusion. Welds shall be as per ASME Code Section VIII
Division 1, Table UW-12, NO.1.
Vessel Supports
The type of supports for vertical vessels shall be as indicated in the specification.
Access opening in skirt, vent holes and piping opening shall be provided in
supporting skirt as per enclosed standard specification.
Skirt and adjoining vessel shell outside diameter shall be the same.
When the inside diameters of nozzles are specified, these shall be maintained.
When the inside diameters of manways are specified, it shall be considered as a
minimum.
Nozzles, openings and their reinforcements shall be attached to the vessels with
complete penetration welds.
Nozzle flanges shall be as per ANSI B 16.5 type and rating as specified.
Substitution of W.N. type flanges with Slip-on type will not be permitted.
All manhole covers shall be hinged or provided with a davit along with suitable
lifting handle. Bolts, Nuts, Gaskets including spares shall be in Tenderer’s scope.
External reinforcing pads shall have a minimum of one vent hole except those
pads for nozzles greater than 400 mm NB shall have a minimum of 2 vents and
nozzles in excesses of 900mm NB shall have 4 vents. Pads installed by sections
shall have at least one vent per section. All vents shall be tapped for future
plugging and plug shall have ¼” NPT connection (max).
Class 300 flanges shall be used as a minimum, unless mentioned otherwise for
pressure relief valve connection.
For heavy wall thickness vessels, integrally reinforced necks are preferred,
although long welding neck flanges and built-up construction are permissible.
Where 125 Ra is specified for flange surface finish, the range for acceptance shall
be 63 Ra minimum to 250 Ra maximum. Finishes shall be judged by visual
comparison with surface finish roughness standards conforming to ANSI B46.1.
Where flange surface finish is not specified, it is the responsibility of the Tenderer
for the gasket specified. Fabricator shall ensure suitable protection of flange faces,
threaded connection, and machined surfaces, during transit.
Lap joint flanges are not permitted in severe cyclic service. An example for sever
cyclic service is defined in paragraph 300.2 of ANSI / ASME B 31.3 piping code.
All flanges intended for use with spiral wound metal gaskets shall be designed
using the manufacturers minimum gasket seating stress or the ASME Code value,
whichever is greater.
The Contractor shall give special consideration for the prevention of over
stressing the flange or bolts during gasket seating, when class 300 and lower
flanges are used with spiral wound metal gaskets.
All opening shall be cut off flush with the inside on the shell and the inside edge
shall be rounded.
Internals like distributor piping, deflector, vortex breaker, tray support rings,
demisters etc. are in Contractor’s scope, including bolting and spares. Details of
demister such as make, make type etc. shall be subject to MECON / Purchaser’s
approval during detailed engineering.
Externals like manhole davit, pipe davit, insulation supports, Pipe supports,
stiffening rings, fire proofing supports, name plate, etc. are in Contractor’s scope,
unless mentioned otherwise.
Sizes of nozzles for safety valve shall be indicated during approval of G.A
drawings by MECON / Purchaser. Contractor’s scope shall include supply of
nozzles with flanges, etc.
Materials
All materials used in the vessels shall be new and of the type and grade specified
in the specifications / drawings. All plates shall be supplied in normalized
condition.
Materials of construction of vent stack and seat drum shall be selected as per the
requirement of NACE, MR-01-75.
Each plate or forging shall be legibly stamped or stenciled showing grade number
and plate or forging number. When metal stamping is done it shall preferably be
on the long edge of each component as it leaves the mill. Metal stamping on rolled
surfaces shall be done with a “low stress” stamp.
Internal support rings shall be of the same material as the shell in killed steel
vessels unless otherwise mentioned, except in lined portions of vessels where they
shall be alloy corresponding to the lining. They shall be continuously welded on
the top and stitch welded on the bottom when carbon steel and continuously both
sides when alloy.
Plates form 16 to 50mm shall be ultrasonically tested as per SA 435 and above
50mm as per SA 578 for an Acceptance Level-1. All bought out items by
fabricator shall meet the relevant inspection requirements and test certificates.
Fabrication
Dished ends in vessels upto 2.0m shall be made in one piece. When a formed head
is made from more than one plate, it shall have a crown plate having diameter
greater than that of the reinforcing pad of any nozzle located at the center of the
head. The central part of cordial seam blank shall be atleast 50mm or 3 times plate
thickness away from the beginning of knuckle curvature. The inside and outside
surfaces shall be MP/DP examined for detection of cracks.
Fabricator shall check for possible fouling / clash or attachments with each other
and with weld seams. Such fouling shall be resolved in consultation with the
Purchaser.
Skirt and other attachment welds shall have complete fusion for the full length of
the weld, and shall be free from undercut, overlap, or abrupt ridges or valleys. All
internal attachment welds shall be continuous, unless otherwise mentioned.
Drawings and instruction for fabrication and installation or tray and mesh blanket
supports attached to the vessel shall be furnished by the appropriate supplier of the
vessels internals. The vessel attachments shall be installed in accordance with the
instructions, and specifications, by the vessel manufacturer. It is the responsibility
of the vessel manufacturer to supply, or cause to be supplied, all materials
required for the fabrication of the vessel attachments for the support of internals.
Insulation supporting lugs / rings / pins / studs at a pitch of 300 mm over vessel
surfaces shall be provided wherever applicable.
Welding
All welding shall be done by a metal arc process. Only approved WPS, and
qualified welders shall be engaged.
Seams in supporting skirts shall be made with full penetration butt welds.
Connections between skirts and vessel heads shall be made with a smooth flat
faced weld, unless otherwise shown. The width of the weld shall be atleast equal
to the skirt thickness, and its height shall be twice its width.
All welding directly t the vessel shall be completed prior to final treatment.
All welded joints for vent stack & seal drum shall be 100% radiographed. As a
minimum requirement all other pressure vessels shall be spot radiographed
(minimum 10%). Each spot radiograph shall be a minimum of six inches (152
mm) in length and in accordance with the ASME code. All welds to be covered by
nozzle reinforcing pads and at least one weld intersection shall be radiographed.
Non-radiographable welds shall be examined by magnetic particle or dye
penetrant as a acceptable alternative.
For vessel shell thickness 2 inch (50 mm) and greater, 100% ultrasonic
examination is required in accordance with the ASME code, after final post weld
heat treatment.
Heat Treatment
Vent stack & seal drum shall be stress relieved after welding to meet the required
hardness etc. as per the NACE stipulations.
For carbon steel formed components, including dished ends, stress relieving shall
be performed as per ASME Section VIII Div. 1, (UCS – 79).
In addition, cold formed carbon steel heads and knuckles shall be stress relieved
when their thickness is 16 mm or greater. Hot formed heads shall also be
Vol. – IIC, Section 01.00 WATER SUPPLY FACILITIES Page 38 of 42
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TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION- I (4X210MW)
normalised in case they are formed at temperatures below the normalizing range.
Hot formed dished ends or similar parts, which have not been uniformly heated in
the normalizing range in the final stages of manufacture shall be normalized.
Vessels in caustic service, amine or sour gas service shall be stress relieved.
Painting
All uninsulated carbon steel surfaces shall be given two coats of epoxy zinc
chromate primer (P-5) with min. DFT of 35 microns per coat followed by two
coats of acrylic polyurethane finish coat (F-2) with min. DFT of 30 microns per
coat.
For insulated carbon steel surfaces, (i.e. Test storage tank) two shop coats of red
oxide zinc chromate primer (P-1) with min. DFT of 35 microns per coat shall be
given.
Earthing lugs shall only be cleaned by wire brush and not to be painted.
Sand blasting is not required for internal surfaces of vessels. Only wire brush
cleaning is required for the same. However, wherever internal surface painting has
been specified, i.e. in Test storage tank, sand blasting will be required.
1. The erection of all plant and equipment shall be carried out according to the latest
engineering practices and according to the drawings, specifications, Instructions
etc. duly approved by the Purchaser / Consultant.
2. The welding work should be carried out as per the approved WPS and PQR.
3. The Bidder shall supply all required manpower, tools and related equipment, all
hoisting equipment, all necessary scaffoldings, all necessary transporting
equipment, consumables. Construction and erection materials, petrol, diesel oil,
kerosene, solvents, sealing compound, tapes, brazing and soldering materials,
welding and brazing gases, erection bolts, nuts and packing sheets / compounds,
temporary supports, wooden blocks, spacers, templates, jute and cotton wastes,
sand/emery paper etc. as required for the satisfactory completion of work.
4. On completion of the work, the Bidder shall remove and dispose off all rubbish
and other unsightly materials caused by his working to a distance of five kilometer
from the proposed Refractory store or as directed by the Purchaser and thereby
leaving the premises in good, clean, safe and operable condition.
5. Before giving call for final inspection, all the documents shall be furnished to the
Purchaser. The record of manufacturing details, inspection and tests carried out by
the successful Bidder shall be made available to the final inspecting authority.
However, approval and final inspection at the manufacturing works shall not
relieve the successful Bidder of responsibility of replacing at his cost any
defective part/material which may be detected by the purchaser during erection
and commissioning or guarantee period.
6. All materials required for fabrication, construction, testing and inspection shall be
supplied by the Bidder. No material shall be free issue to the Bidder.
7. No equipment or part item shall be dispatched without final inspection and
issuance of inspection certificate.
8. All equipment, assemblies, sub-assemblies shall be shop tested as per relevant
standards and the test certificates shall be submitted by the supplier.
9. Erection, testing & commissioning of various equipments and piping etc shall be
done also inline with details given in various chapters of GTS.
01.05 Painting
The Bidder shall submit the following drawings/ documents along with the tender
1. Scheme of the complete water supply system with descriptive and illustrative
literature.
2. Process flow diagram indicating the water consumption figures complete with
temperature, pressure and quality requirements.
3. Duly filled in data sheets for various valves, fire-hydrants and other equipments as
applicable in line with in the GTS.
4. Pipeline materials and specifications considered for various systems.
5. Layout drawing showing the battery limits of drinking water, fire fighting water
and the pipeline route to various consumers including requirement of drinking
water and fire-fighting water at battery limits.
6. Catalogues, literatures and GA drawings of all equipments and valves.
7. List of special tools and tackles.
8. List of commissioning spares.
Vol. – IIC, Section 01.00 WATER SUPPLY FACILITIES Page 40 of 42
© 2020 MECON Limited. All rights reserved.
TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION- I (4X210MW)
9. List of spares for two years of normal operation and maintenance with item wise
prices.
10. Specification and capacity of all equipment, valves etc. offered by the Bidder.
11. Tentative Bill of Quantities covering all equipments, valves, strainers, pipelines,
etc. and associated civil, structural items etc.
1. Process flow diagram indicating the water consumption figures complete with
temperature, pressure and quality requirements.
2. Layout of piping system indicating pipe routing, location of supports, valves and
other fittings as required.
3. Data sheets and technical details of all the equipments, valves and piping.
4. Test procedures for preliminary and final acceptance tests.
5. Quality Assurance Plan.
6. All equipment and piping sizing calculations.
7. Test certificates for the following:
Material test certificate for all major equipment and their components.
Hydraulic test of equipment, pipe fittings & valves.
Static and dynamic balancing of all rotary parts/ equipments
8. Any other drawing/ documents as required by the Purchaser.
1. The successful Bidder shall submit required sets of all the approved drawings,
documents and manuals for Purchaser’s record and use. After erection of
equipment, the Bidder shall submit one set of linen tracings/ reproducible in
required number of prints along with soft copies in CD (in AutoCAD format) of
each “As built drawings”.
2. Operating and maintenance manual.
3. Spare parts recommendation and price list.
4. Instruction for erection, testing and commissioning.
5. Manufacturer’s test certificates.
6. Various equipment assembly drawings and bill of material.
7. Welding procedure.
8. Hydraulic test logs.
9. Equipment GA drawings and bill of materials.
10. Operation and maintenance manuals for all equipments, valves and complete
water system along with soft copies.
11. Test and calibration certificates.
12. Warranty/ guarantee certificates.
13. Technical literature, catalogues and manufacturer’s drawings for all brought out
equipment, valves and other items.
14. All inspection/ test report/ certificates.
15. Any other drawing/ documents as required by the Purchaser / Consultant.
02.01 Introduction
To control the dust load in the flue gas coming out from the absorber and to maintain
stack emission within allowable environmental norms, bag filter based de-dusting (dust
extraction) system shall be considered. The scope of work, description of the systems,
equipment, design criteria, general instructions to tenderer, etc. are furnished below.
The scope of work of the turnkey package executer shall also include the design,
engineering, manufacture / procurement, inspection, supply, transportation to site,
unloading and site storage, testing, erection, painting, commissioning and performance
guarantee of the complete dust extraction systems (DES) and Air conditioning &
Ventilation Systems (ACVS) including electrics, instrumentation, civil & structural
work as per the scheme drgs. The bin vent filters with fans and necessary pulsing
arrangement shall also be provided for the silos (lime storage silos, intermediate silo &
main silos).
The bag filter based de-dusting (dust extraction) system shall comprise online pulse jet
bag filter unit, air dilution motorized damper at the inlet of bag filter, suction duct
carrying dusty air, clean / filtered air outlet duct connecting to stack, fabric expansion
joints at inlet & outlet, on-line bag cleaning system, dust transportation system from bag
filter hoppers to the intermediate dust storage silos, structural supports, electrics,
instrumentations and controls, etc. Air dilution damper shall be required to regulate the
inlet temperature of dust laden flue gas as per the requirement and to safe guard the
bags. The bag house shall have thermal insulation / cladding to take care of safety as
well condensation issues, if any.
Bag filter unit shall also have inlet/ distribution chamber, filtering chamber with filter
bags and fittings for the bags, outlet chamber, dust collection hoppers with heater,
vibrator, insulation, manual slide gate & rotary air lock valves, dust storage – cum –
disposal hopper with rotary air lock valve, slide gate (for alternate chute) & disposal
chutes, structural stair case & platform, electric hoist for handling top cover / bags /
cages, etc. The tubular cloth bags (filter bags) shall be held vertically in the cages in the
filtering chamber with the top face open to the outlet chamber of the bag filter unit. A
minimum distance of 75 mm (approx.) between the bags and between bags & the
surface such as walls or columns of the casing shall be provided. The outside surface of
the bags shall be exposed to the inlet/ distribution chamber of the bag filter unit.
Weather protection shed (rain proof), side sheeting, rain water pipe, digital instrument
as well as pressure transmitter for monitoring of pressure drop across bag filter and
Vol. – IIC, Section 02.00 ACVS Page 1 of 88
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TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
across each module and its display provision in the control room / panel, etc shall be
considered. Each module of the bag filters shall have pneumatically operated dampers at
inlet & outlet. The filter & hopper shall be provided with heaters to allow for free flow
of dust. Proper insulation shall be provided for the de-dusting filters and ducting
systems. Dusty air entry to bag filter modules shall be from the bottom of the bags. In
case of side entry, necessary baffles shall be provided to direct the flow to the bottom
and ensure that the dusty air enters the bags only from the bottom. Uniform air
distribution in the bag filter modules shall be ensured and shall be demonstrated during
the testing / cleaning of bag filter. The design calculation for the sizing of compressed
air distribution line & its header shall be submitted along with the GA drg. of bag filters
during detailed engineering.
The bag cleaning system shall consist of compressed air main header piping (connected
to compressed air supply network of the plant), manual valve, pressure regulator, air
manifold tank, solenoid valves with timers and array of pipes with nozzles, sequential
timer, control panel, DP switches, pressure gauges & transmitters, etc. The main
compressed air header pipe coming from compressed air supply network shall be taken
into an air receiver and shall then be connected to the air manifold tank through manual
valve & pressure regulator, etc; the air manifold tank shall be connected to the array of
compressed air pipes with nozzles through solenoid operated valves with timers. The
network of timers for the solenoid operated valves shall be provided / set in such a way
that during operation of the de-dusting (dust extraction ) system/ plant, periodic pulse
jet cleaning of the filter bags is achieved by blowing compressed air into each bag
periodically. There shall be dedicated compressors, dryers & air receivers with 100%
standby (for compressor & dryer) for each bag cleaning system.
The dust collected at the dust collection hopper shall be taken into the dust storage silo
through dust transportation system. This collected/ stored dust shall be disposed off by
central pneumatic conveying system to the main storage silo.
The bags shall be made of Nomex needle felt cloth with PTFE surface treatment for
main de-dusting system. However, Polyester needle felt cloth with PTFE surface
treatment shall be provided for silos. The minimum wt. of bags shall be 550gm/m2. The
filter bags shall be stitched with 3 rows of thread. The bottom shall be closed with fabric
disc and top shall be open with SS 304 snap band. Air permeability shall be 175
lpm/dm2/min @ 20mmWG. Fabric thickness shall be 2.1mm + 10%. Muller Burst
value shall be 35Kg/cm2 + 10%. PTFE laminated coating shall be provided on the bags
to ensure surface filtration. The PTFE membrane shall be thermally laminated on to the
bags without the use of adhesive. The bag shall withstand upto the temperature of
200°C.The outside surface of the bags shall be exposed to the inlet / distribution
chamber of the bag filter unit. The inside of bag house chamber, cages, tube sheets, etc.
shall have acid proof treatment. The length of bags shall be 6 m preferably.
Bag cage shall be of 5mm galvanized steel wires. Wires shall of minimum 4mm
diameter. No bend of wires shall be allowed. Absolute straightness of wires shall be
ensured. Sufficient nos. of vertical wires shall be provided to give strength to avoid
collapse of cage as well as to prevent draw of fabric between wires.
Thickness of casing of bag house shall be minimum 5mm and that of hopper minimum
6 mm and these shall be suitably stiffened from outside and treated with acid proof
coating from inside. All bag filter hoppers and dust storage silos shall be provided with
2 motorized bin vibrators each.
The following specific aspects shall be particularly taken care of while designing and
executing the project :
1) Structural stair case and platform all around the bag filter shall be provided in such a
way that easy approach shall be made available for inspection and/ or maintenance of
the filter bags, compressed air piping with nozzles installed inside the filtering chamber,
air manifold tank, solenoid operated valves, timers and bag filter inlet & outlet dampers,
etc.
2) The minimum platform width shall be 1.2m. Railings should be provided on the
platform. Intermediate platforms shall be provided for the bag filters and hoppers for
inspection and cleaning purpose. Staircase shall be provided upto roof top of bag filter,
silo and chimney. Necessary maintenance platforms to attend the electric hoist of bag
filters, silo & stack shall also be provided. 1m wide spiral staircase shall be provided for
stack. Following minimum structural member shall be considered:
7) Pulsing pipes on top of the clean air chamber of bag filter shall be supplied loose and
shall be erected at site after erection of the clean air plenum.
8) All platforms and stair supports shall be independent of casing. Separate stair tower
may be envisaged. All other places, staircases shall be provided. Minimum loading for
the platforms shall be considered as 600kg/m2.
9) Plenum chamber (inlet/outlet duct) shall be independently supported from the main
columns by horizontal members with air entry to individual modules by cross duct from
the main inlet/outlet duct. They shall not be supported directly from the casing since in
such a case, erection is difficult.
10) MS Gratings for platforms and staircases shall be suitable for heavy steel plant duty.
11) Base plates of columns shall match with the foundation so as to allow sufficient bearing
area for providing the pack plates below columns. Proper shear key shall be provided.
12) Erection drawings shall indicate clear-cut assembly details with tag nos. The structural
support members shall be supplied with erection bench marks, erection holes and
erection bolts.
13) BOM and total weights of the bag filter components and support structure shall be
clearly indicated in the erection drawings. In absence of these, it is not possible to plan
for required size of crane and generation of monthly plans and erection reports.
14) All columns shall be supplied for bolt type fixing. Columns with insert type fixing are
not acceptable.
15) Minimum 2.5m clear space below the bag filter hopper shall be kept for the equipment
of dust transportation system.
16) Access door at hopper shall be provided.
17) Adequate safety measures including the explosion vent shall be taken into consideration
for flawless operation of the bag house.
The cleaning operation of the bag filter shall be on-line and automatic with the help of
PLC system. One module of bag filter of similar capacity shall be kept isolated for
maintenance purpose so that at any moment of time, effective volume of working
modules vis-a-vis the air to cloth ratio shall remain same. The online cleaning shall be
accomplished by means of compressed air pulse jet through pulse solenoid valves
controlled through PLC software. Cleaning operation of different modules of bag filter
shall be in sequence with a preset interval time. The cleaning of bags in a module also
takes place in a sequence. The time interval of cleaning operation between modules and
compressed air pulse duration & frequency are adjustable to maintain pressure drop
across bag filter in the range of 140mmWC.
Tentative design parameters for pulse-jet fabric filter based DE System shall be as given
below:
Flue gas flow – 10,94,650 Nm3/hr @ 140 deg C having moisture content 12%
(approx.).
Inlet dust load to bag filter – 4000 mg/Nm3.
Outlet dust load from bag filter to be restricted to 70mg/Nm3
Duty – continuous operation.
Maximum pressure drop across the bag filter shall not exceed 150 mmWG.
Air to cloth ratio - 1.1 m3/min/m2 (max).
Electric hoist for handling of top cover / bag cage.
Explosion vent and pent house shall be considered.
The selection/ design and manufacture of plant and equipment shall be suitable for the
intended service and the atmospheric/ environmental conditions prevailing at Mettur,
Tamil Nadu. Design and selection of equipment shall be made with the following also
in view:
a) Safety of personnel
b) Uninterrupted operation
c) Long life of equipment
d) Easy maintenance at low cost
e) Lowest operating cost
f) Spares availability
g) Co-ordinates and location of the building.
h) Equipment, piping and ducting layout
Bag filter hoppers and dust storage silo shall have 65 degree valley angle. Pneumatic
dust conveying system shall be provided to feed the dust from the intermediate dust
storage silo to the main storage silo. So, the clear height below the telescopic chute /
discharge valve of the intermediate dust storage silo shall be minimum 3.0m to
accommodate the downstream dust transportation system. The silo shall have minimum
24 hours dust storage capacity with 20% margin over its geometric volume. Thickness
of dust storage hopper shall be minimum 8 mm. One Rotary Feeder having capacity of
100 TPH direct coupled, one manual knife edge gate valve and telescopic chute shall be
provided under dust storage silo. Vibrator shall be provided for easy flowing and
unloading of dust from the storage hopper. Supporting column width of dust storage silo
shall be 5m to facilitate the movement / parking of heavy vehicle.
Vol. – IIC, Section 02.00 ACVS Page 5 of 88
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TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
An insertable type bag filter with other accessories (including fan) shall be provided at
the top of the silos to reduce the dust spillage to the atmosphere during feeding of dust
into the silos. High level switch and safety alarm arrangement shall be provided in the
silo so that in case of high level of dust, the safety alarm will get activated through the
PLC. Necessary interlock shall be suitably considered & provided. Additionally, a
safety valve at the top of the silo shall also be provided as a safety measure wherever
the silos are fed through pneumatic dust conveying system. Insertable type bag filter
with other accessories (excluding fan) shall be provided at the top of the silos (which
are fed through pneumatic dust conveying system). The pneumatic dust conveying
system shall be designed in such a way that the pressure of the pneumatically conveyed
dust at the entry of main dust storage silo shall not exceed 200 mm WC. In case, the
entry pressure exceeds the set value (to be finalized during the commissioning stage)
then the safety valve mounted on the top of the storage silo shall open & release the
excess pressure. Necessary instruments & interlocking to this effect shall be designed &
provided. An expansion joint shall be provided in between the contact surface of bag
filter & silo top. Bag filters for such silos shall be accordingly designed. Staircase with
intermediate platforms (1.2m width) shall be provided upto the top of silos.
02.08 Thermal insulation (applicable for both de-dusting and Air conditioning system)
Thermal insulation shall be provided for the bag house, hopper, ducting, intermediate
silo and the hot surfaces, if any. Thermal insulation system shall be selected so as not to
result in a residual heat loss exceeding 150 Watts/m2 under plant operating conditions
measured over insulated surfaces. For design, the following data shall be referred :
Design should include de-rating factors of direct conduction paths e.g. spacer rings and
stitching wires normally associated with blanket type insulation material.
IS 8183: 1993 (RA 2004) Specification for Bonded Mineral Wool, Group – III &
IV
IS 9842: 1994 (RA 2006) Specification for pre-formed Fibrous Pipe Insulation,
Group– III
IS 14164 : 1994 (RA 2001) Industrial application and finishing of thermal insulation
material at temperature above -80 deg C and up to 700
Vol. – IIC, Section 02.00 ACVS Page 6 of 88
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TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
Application procedure :
a) Piping:
• For surface preparation wire brush shall be used to remove rust, dust or oil etc.
thoroughly.
• Fix the pre-formed pipe-section insulation of required thickness against each diameter
of pipe as per the thickness requirement for temperature class and pipe diameter.
Construction (upto 75mm thick – 1 layer thereafter 2 or 3 multi layer) joints should be
staggered so that complete breaks are minimum on single layer insulation and no
through joints occur in multi layout work. The insulation must be held in position by
strapping with 20mm x 24 SWG Aluminium Straps.
• When lightly bonded rock wool mattresses are used, they shall be wrapped around the
pipes without any under layer. On top of each layer, the wire netting already on top of
mattresses should be tightly butted against each other so that the fibers interlock both
along the longitudinal and circumferential joints. The pipe joints shall be stitched with
22 SWG soft GI lacing wire for pipes upto 400mm O.D. For pipes over 400mm O.D.,
the mattresses should be further secured by strapping with 20 mm x 24 SWG Al. straps
at 500mm intervals.
All un-insulated flanges, pipeline insulation shall be stopped off at a suitable distance
from the flange for facilitating withdrawal of bolts without disturbing insulation.
When supporting insulation of vertical pipelines it is essential that all the pipe insulation
(above 200 NB pipe) should be supported at minimum of 3.0 meters distance by
applying insulation support spider clamps. These clamps are fitted around the pipeline
bare surface with projecting legs whose length should not be more than 70% of
insulation thickness.
Flanges and Valves: Removable covers shall be provided over all flanges and valves
whenever they are insulated with preformed materials. These covers over valves and
flanges shall have provision for quick – release clips.
Sheet Metal Cladding: All pipes shall be covered with Aluminum sheet (24
SWG/0.56mm upto 325mm O.D. inclusive of insulation thickness and 22
SWG/0.71mm beyond 325mm O.D.) conforming to IS 737: 1986 (RA 2006), to the
outside of the insulation with minimum 25mm circumferential and longitudinal over
laps. The overlapping should be grooved so as to prevent ingress of water into the
insulation. In horizontal piping, joints shall be arranged at an angle of 30 to 40o from
the horizontal so as to shed rain water.
When lightly bonded rock wool mattresses have been used as the insulation material,
spacer rings shall be required screwing the Aluminum sheet. The sheet metal shall be
secured to themselves by self-tapping screws at a pitch not exceeding 150mm.
After securing the Aluminum sheet, the overlapped joints of the sheet metal shall be
sealed with metal sealant to make joints perfectly waterproof.
• The surface to be insulated shall be thoroughly cleaned by wire brushing to remove dirt,
loose scales, dust etc.
• Where welding is permissible, weld 10 SWG GI spokes at 300 – 400mm diamond
pitch.
• `L’ shaped lugs to be fixed to the spacer rings made of 25mm x 3mm MS flats at
450mm C – C with 25mm x 25mm x 3mm asbestos mill board washers and 4mm MS
rivets.
• The spacer rings shall be fixed around the tank at 900mm C – C by welding `L’ shaped
lugs to tank body.
• Impale Rock wool lightly bonded machine stitched mattresses with one side wire
netting of required density (upto 400o – 100 Kg/m3, above 400oC – 120 Kg/m3) and
thickness, with the ends of mattresses butted closely together with lacing wire of 22
SWG. In addition, mattresses shall be secured with tightly tensioned circumferential
Aluminium bands at approx. 450mm pitch.
• The ends of GI spokes shall be bent on the insulation.
• The Aluminium metal cladding (22 SWG/0.71mm) is to be fixed on the spacer rings
with self-tapping screws at 150mm C – C.
• All over lapped joints of Aluminum sheet metal shall be sealed with loidseal-94 to
make joints waterproof.
c) Expansion joint :
Expansion joints shall be provided in the insulation to allow for movement and
expansion of the pipe or vessel without producing random cracks. At the expansion
joints, there shall be complete cut and the cutout portion shall be 25mm wide and dry
filled with loose insulation material the density of which shall be equal to that of the
basic insulation. The expansion joints wherever necessary shall be installed by
overlapping the cladding material.
d) Design Criteria :
Note: For piping upto 325 mm OD (including insulation thickness) aluminum sheet
thickness – 24 SWG (0.56mm) and beyond 325 mm OD (including insulation
thickness) aluminum sheet thickness – 22 SWG (0.71mm).
Rotary air lock valve shall be made of cast iron with the carrying side hard faced. The
rotary air lock valve shall be complete with shaft of EN8, cast iron housing, rotor blade
(detachable type), etc. Rotary air lock valve is directly coupled to gear box & motor.
Rotary air lock valve capacity shall be based on 50% filling volume. Rotor blade shall
be of MS construction and hard faced. Face of blades shall be hard faced by 20x15
diamond weld beads (2 to 3 mm ht) to achieve 250-300 BHN hardness.
Casing thickness : 6 mm
Rotor blade thicknes : 5 mm
Capacity : Bidder to finalize as per system requirement
RPM of RAV : Not more than 20
Vol. – IIC, Section 02.00 ACVS Page 9 of 88
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TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
Manually operated slide gate shall be provided above RAV in the bag filter hopper for
isolation purpose for maintenance.
Telescopic Chute
Telescopic chute with knife edge gate valve above RAL shall be provided for
discharging the dust from the storage hopper into the closed truck.
Ducting Network shall comprise ducting, duct support, measuring hatch, cleaning hatch
and duct line dampers as required along with necessary external stiffeners, flanges,
counter flanges, fasteners, gaskets and other accessories.
Construction
The duct sizing shall be so selected to maintain proper conveying velocity throughout
the system. Man holes/hand holes and dust outlets shall be provided at intervals to
facilitate cleaning of dusts and for disposal of dust. The ducting shall be fabricated from
M.S.(IS 2062: 2006) having thickness as follows unless otherwise specified in the job
specification :
At all duct bends (carrying abrasive dust) above 900 mm diameter shall have abrasion
resistant liners with caster wood / rock basalt / FRP in line with job specification
requirement.
Thickness of flanges shall be 12 mm. Necessary stiffeners shall be provided in the duct
depending on size. The ducts shall be laid vertical as far as practicable for dedusting
installations and horizontal ducts should be avoided.
For special application corrosion / abrasion resistant duct liner material of construction
of FRP / Liner material may be required to be installed in line with job specification
requirement.
Conveying velocity
A conveying velocity of 18-25 m/s shall be maintained at all points in the ductwork to
ensure flow of dust laden air without settling of dust.
Expansion joints shall also be provided in the ducting network to reduce thermal stress
as required.
Main duct and all major branch ducts shall have two 100mm diameter capped sockets
installed at 90° to one another at least 8D away from flow disturbance (bends, hood
inlets) for insertion of pitot tubes for flow measurement and system balancing during
commissioning. Test points are to be located in a readily accessible position in the duct.
However in any suction hood if flow appears to be on the lower then necessary flow
measurement and correcting device shall be made by the successful tenderer to suit site.
Interconnecting duct work shall be circular in cross section. The duct work shall be
fabricated from mild steel plate, IS 2062:2006 or be seam welded spiral wound duct
work as per job specification requirement.
Branches
Branch connections should be oriented to the top or side of the main with no two
branches entering at opposite sides.
Joints
Matching flanges are to be bolted together with asbestos rope gasket or rubber gaskets.
All bolts and gaskets for jointing shall be included in the scope of work of the
successful tenderer. All duct joints are to be air tight to minimize air leakage.
Clean-out doors will be provided on horizontal runs, before elbows and junctions. The
spacing between cleanout doors should not exceed 6 meters. Clean out doors will be
constructed to have a diameter of 600 mm or the duct diameter whichever is less for
ducts upto 1 meter diameter. Larger diameter ducts will have clean out doors sized 600
mm high by 600 mm wide.
The ductwork support spacing and hangers will be designed for the weight of settled
dust plus a 25% design margin. Following dust load will be considered for designing
duct and duct support and duct stiffeners.
Vol. – IIC, Section 02.00 ACVS Page 11 of 88
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METTUR THERMAL POWER STATION - I (4X210MW)
Duct dia (in mm) % Cross section of duct filled up with dust.
500 and below 70 %
Above 500 to 1000 50 %
Above 1000 diameter 30 %
All duct inside buildings and duct along main structural building will be supported from
plant building structure or as approved during detailed engg. Details of duct supporting
members will be decided during detail engineering. To suit site condition, supporting
members may have to be modified by the successful tenderer without any commercial
implication to the purchaser. All outside ducting network shall have independent duct
supporting trestles.
Ductwork Layout
Ductwork will not interfere with fixed or mobile crane access to the plant. Horizontal
run of the ducting will be avoided to prevent settling of dust.
Minimum horizontal clearance from road center line is 5 meters. It is the responsibility
of the successful tenderer to effect the dedusting system ductwork arrangement in
accordance with the design requirements set down in the specification and to the
satisfaction of the purchaser / consultant.
Ductwork integrity
The successful tenderer shall design the ductwork in such a way to ensure that the
ductwork will not collapse at any point, should it be subjected to the maximum suction
capacity of the fan system. The design shall accommodate any variation in ambient
temperature.
It is the responsibility of the Successful tenderer to size all ductwork in detail as per
duct balancing calculation. Duct balancing calculation will be furnished by the
successful tenderer for approval of the purchaser. It is the Successful tenderer’s
responsibility to establish routes both inside and outside building. This is to be done in
conjunction with and to satisfy the Purchaser.
The duct work will be self pressure-balanced type. However, during testing and
commissioning if any throttle piece is required for adjustment of flow in any duct
branch, same will be carried out by the successful tenderer without any commercial
implication.
Flexible connection / expansion bellows at inlet & outlet of bag filter and in the ducting
network shall be provided by the successful tenderer as required along with the back-up
calculation for fixation of such expansion joints / supports (sliding / fixed type).
All expansion joints will be fabric type construction, mounted between flat face flanges.
Internal liners are required to prevent the dust laden air from coming into contact with
the fabric material and shall be designed so as not to reduce the nominal joint
dimensions. Flow direction shall be clearly identified on each expansion joint to ensure
correct installation. The Tenderer will define MOC and technical reasons for their use
for the following components of the expansion joint assemblies:
02.12 Dampers
All damper components will be weatherproof construction mounted between flat face
flanges. Lifting lugs will be provided. Flow direction shall be clearly identified on each
damper to ensure correct installation. The dampers shall be suitable for installation in
both horizontal and vertical ducting. Suitable rubber packing / 3mm gasket shall be
provided at the flanged joint to make the system leak-proof. All dampers shall be
located with suitable approaches provided by the Tenderer. The design and material
selection of damper assemblies will be capable of meeting the process requirements. All
damper valves will be clearance or ribbed type butterfly dampers, shaft mounted on
frictionless bearing with flat face flanges. System will fail in the open position at loss of
pneumatic or electrical signal. Each limit switch will be supplied with open and closed
contacts. Rate of damper leakage in the fully closed position is to be given as a
percentage of the normal flow with the damper open and shall not exceed 1%.
Damper valve body, disc, and shaft and de-clutchable manual over-ride will be carbon
steel construction, suitable for the rugged service demands encountered during blast
furnace cast house operation.
Spring return pneumatic actuator shall be provided for “open-closed" service dampers.
They shall be operated with compressed air to close and spring to open. Necessary limit
switches shall be provided for position control and indication for all dampers.
Actuator will be spring return, single acting, electrically operated for 0 to 90 degree
travel. The entire train will be totally enclosed within single cavity housing. Actuator
will have external manual indication of valve and output shaft position. Indicator shall
be of corrosion resistant materials in contrasting colour to actuator body. Indicator shall
be the sole external moving part.
Actuator will be capable of being mounted directly to the damper. Actuator will be
complete with external de-clutchable manual over-ride which will have safety interlock
to exhaust air from actuator when manual mode is selected. All moving parts must be
totally enclosed. Actuator will be operable with valve installed in any position without
loss of performance and will be mounted parallel to the pipe.
Actuators are to be sized to operate with compressed air supply 5 to 7 Kg/ cm² pressure.
Actuator will be complete with position indicating switches. Switches will be totally
enclosed, in approved IP-65 enclosure, for corrosive environments. Switches will be
CAM operated and cams will be independently adjustable throughout the full actuator
travel range. Switches will have external position indicator to the same specification as
the basic actuator. Actuator will also be complete with electro-pneumatic valve
positioner, suitable for spring return, fail-open operation and manual over-ride.
Actuator housing will be hard anodized, extruded aluminum. End caps and pistons will
be pressure die-cast aluminum. Output shaft will be heat treated steel. All actuator seals
will be of Nitrile material and will be of O-ring construction.
Manual Over-ride
The de-clutchable manual over-ride mounted on the damper / valve will be of a worm
and segment actuator, in which the worm-drive shaft can be rotated eccentrically by the
worm-drive lever to disengage the worm from the segment. The segment is then free to
rotate when driven by the actuator.
The drive-shaft will have an internal locking device to lock it into the selected mode of
operation.
Normal operation is with the worm-drive lever in the "auto" position. In this position,
the worm-drive will be disengaged from the segment gear, and the actuator will be free
to rotate the valve shaft.
To engage the de-clutchable manual over-ride, the worm-drive locking button, mounted
on the unit, will be released allowing the worm-drive to rotate to the "manual" position.
02.13 Valves
pressure of the system served. The broad specifications for the different categories of
valves pertaining to compressed air & water line are as follows:
a) Isolation valves – for size 50NB and below, ball valve screwed as per IS 778 :
1984 (RA 2005) class 2. It will have SS ball & cast steel casing.
- For size above 50 NB, butterfly valve with SS disc & cast steel casing shall be
provided.
b) GM globe valves – screwed as per IS 778: 1984 (RA 2005) class 2 shall be used
for control valves.
c) Non-return valves – GM check valve (lift type) screwed as per IS 778 : 1984 (RA
2005) class 2 for NB – 50 and below. C.I. check valve flanged as per IS:5312 :
Part I : 2004 for NB 65 and above.
The instrumentation system shall be designed using PLC based instruments unless
otherwise specified. Tenderer shall offer all the measurements, alarms & interlocks as
may be required for efficient & satisfactory operation of their offered system. Following
are the indicative list of measurements, alarms and interlocks for de-dusting system:
1. Alarm annunciation and interlocking for high level of dust in each bag filter hopper and
each storage hopper.
2. Indication of differential pressure across bag filter. Alarm and interlocking signal shall
be generated through PLC software. Purging arrangement shall be provided in the
impulse lines. Rotameter shall be considered for purging medium (compressed air) flow
regulation.
3. Indication and control of temperature for dust laden air at the inlet of bag filter. Alarm
annunciation and interlocking signal for high temperature shall be generated through
PLC software.
4. Indication of compressed air pressure at the compressed air header at the inlet of de-
dusting unit.
1. Local indication of pressure & pressure low alarm for the compressed air header at the
inlet of each bag filter unit (through separate pressure gauge & blind type pressure
switch).
2. Local indication of pressure for the air at the outlet of bag filter of dedusting unit
(through diaphragm seal type pressure gauge)
3. Local indication of differential pressure across each bag filter. Purging arrangement in
the impulse line shall be provided.
4. Any other measurement and controls, alarms and interlocks required for the safe and
reliable operation of the De-dusting System shall be provided by the Tenderer.
A. General:
All instrumentation equipment shall be suitable for operating continuously under the
environmental conditions indicated below:-
Colour code applicable for the entire plant as per Client’s choice/ relevant standard shall
be followed for instrumentation pipelines, lamps, cables, panels, etc. Instrument power
supply shall be single phase 230V AC ± 10%, 50 Hz ± 5% as per prevailing condition at
Vol. – IIC, Section 02.00 ACVS Page 16 of 88
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TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
Mettur work / project site. All instrumentation equipment shall be suitably selected
accordingly. No instrument contact shall be used directly for alarm annunciation or
interlocking. Contacts after multiplication through relays shall be used for alarms and
interlocks. Instrument power supply shall be through circuit breaker (with adjustable
short circuit and overload release facility) and isolating transformer. Circuit breakers
shall also be provided on the secondary side of the isolating transformer for providing
power supply to a group of 2-3 instruments. All instruments shall also have individual
switch fuse units. Power supply equipment for instruments as may be required for Local
& Control panels shall be installed inside the panels.
RTD shall generally be used for measurement in the temperature range of -200ºC to
300º C and thermocouples for higher temperatures. For all control applications,
requirements involving duplication of temperature signals and plant specific
requirements, temperature transmitters shall be used. Head mounted type transmitters
shall not be provided. RTDs shall usually be three-wire type. Four-wire type RTDs shall
be used whenever specifically required.
Thermocouples shall normally be mineral insulated (i.e., extruded MgO) type. RTD/
Thermocouple assembly shall be spring-loaded to ensure positive contact with thermo
well. Measuring junction of thermocouples shall be grounded or insulated depending on
the type of electric system or safety protection requirement. Thermo wells shall be
provided for all applications to enable maintenance work of thermocouple / RTD
without affecting production. Thermowells shall be bar stock type for upto 600 mm
immersion length and fabricated type for immersion length more than 600mm. AISI 316
shall be used as thermo well material, unless other special material is required due to
process fluid and conditions. Thermocouples shall be complete with compensating
Vol. – IIC, Section 02.00 ACVS Page 17 of 88
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TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
leads, installation fittings. The indicators, controllers shall have broken sensor
protection. Interconnections to / from thermocouples to temperature transmitters/
automation systems shall be made via compensating cables of thermoelectric
characteristics matching with thermocouples. In case, temperature elements, extension
cables, compensating leads are to be laid on the top of furnace /hot surface, suitable heat
insulation protection shall be provided. Use of asbestos shall be avoided. Mineral
insulated cables shall also be used for such applications. JB for connecting
compensating cables shall have terminal blocks suitable for type of thermocouples to be
connected. A protection tube consisting of a gas-tight ceramic sheath preferably
reinforced with stainless steel shall be provided with Pt-Rh/Pt thermocouples unless
some other special construction is specified.
Bourdon tube (spiral or helical), bellows or diaphragm type sensing element shall be
used in pressure gauges/ switches, depending on the process application. The gauges
shall be designed in accordance with IS 3624. Accuracy shall be ±1.0% of span for
pressure gauges and ±1.5% of span for DP gauges. Accuracy shall include the combined
effect of linearity, Hysterisis and repeatability. The element and other wetted part
materials of pressure gauges/ switches shall be of AISI 316, unless process media
necessitates use of other materials. Movement material of gauges shall be of AISI 316.
Outer casing and bezel material shall be either made of die cast Aluminium with epoxy
coating or of AISI 316. Pressure gauges shall have external zero adjustment facility and
minimum IP55 housing. These shall have a linear scale and dial colour shall be white.
Pressure gauges shall have dial size of 150 mm diameter. Gauges of smaller dial size
may be used for machine- mounting applications. Window material of pressure gauges
shall normally be toughened glass. However, where the pressure exceeds 40kg/cm2,
window material of the pressure gauge shall be shatterproof glass. Pressure gauges &
switches shall be provided with 3 – way/ 2-way gauge cocks. These items shall be
provided in addition to the isolation valves/ root valves at the process tapping point. The
working range of pressure switches shall be selected in such a way that the set pressure
is between 35% and 65% of the range. The switch enclosure shall be weatherproof to IP
65. Pressure switches shall have repeatability of at least ± 1% of span. These shall have
in-built scales.
D. Transmitters:
Pressure, flow, differential pressure and level transmitters shall be rugged, industrial,
microprocessor based ‘Smart’ type. Transmitters shall work on 24 V DC power supply
having 2-wire, 4-20 mA DC output & ‘HART’ protocol based or field bus based digital
communication. Accuracy of all transmitters shall typically be 0.1% or better of
calibrated span for turn-down ratio of minimum 10:1 and rangeability of 100:1.
Accuracy shall include the combined effects of linearity, hysterisis and repeatability. In
any application, the worst case error (WCE) consisting of static pressure effect,
Vol. – IIC, Section 02.00 ACVS Page 18 of 88
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TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
temperature effect, humidity effect and stability (1 year) shall not be greater than 0.75%,
unless specified otherwise. Zero and span adjustments shall be non-interacting to each
other. Transmitters shall be suitably compensated against any thermal effects in the
process medium. Transmitters shall be able to withstand a minimum over pressure of
150 % of the rated pressure. All the transmitters shall be weather-proof to IP-65 or
better. Zero suppression & elevation features, surge protection and provision for
selection of different damping levels shall be provided in each transmitter. Absolute
pressure transmitters shall have provision for compensation of barometric pressure. All
transmitters shall have integral local linear digital indicators calibrated in engineering
unit. DP transmitters for flow applications shall have built-in square root extractors.
Local indications shall be adjusted / calibrated through hand held calibrator. Pressure
transmitters shall be supplied with 2-valve manifolds of AISI 316 material. Flow; DP
and level transmitters shall be supplied with 3-valve manifolds of AISI 316 material
having suitable pressure and temperature rating. Standard zero suppression/ elevation
facilities and output reversal facility shall be available for all transmitters. All the
required accessories for mounting shall also be supplied with the transmitters. However,
for purging requirement, pressure transmitter shall be supplied with 2-valve (3 way)
manifold and DP type transmitter shall be supplied with 3-valve (5 way) manifold. All
transmitters shall be provided with traditional mounting arrangement along with
manifolds. For corrosive atmosphere, transmitter body, mounting accessories, nuts &
bolts etc. shall be of stainless steel. One hand-held calibrator with required software,
rechargeable battery and battery-charger shall be supplied for calibration checks of the
transmitters. For HART protocol based instruments or foundation field bus based
instruments. However, laptop based calibrator shall be supplied for profibus PA based
instruments, in case hand held calibrators are not available. Transmitters shall be
provided with external lightning protection devices, wherever required. Wherever
transmitters shall be installed in a room, proper ventilation shall be provided for that
transmitter room.
E. Level Switches:
External displacer type instruments with rotatable head shall usually be used for level
measurement up to 1200 mm (48”). Torque tube shall be made of Inconel and
displacers/float of AISI 316., unless otherwise specified. Side-side flange connection
shall normally be used for level switches. Heat insulator / finned extension shall be
used for temperatures above 230°C. All such instruments shall have drain valves and
vent plugs. Vibration fork type level switches shall be either external cage type
construction or shall be standpipe mounted type. Process connection to the cage shall
be 1“ socket weld type, unless otherwise specified.
For level measurement in non-conducting tanks or sumps or when the tank profile is
non-linear, capacitance type instruments shall be provided with a reference electrode /
ground probe. Capacitance type level probes may be used for both switching as well as
for continuous level measurement in liquids. Capacitance type level probe shall not be
used for level measurement in solids when there is likelihood of material build-up on
the probe. Capacitance type level probe shall not be used in liquid service where there is
a chance of di-electric value change (due to oil spillage etc.).
Following Indian Standards shall be followed for designing Air Conditioning System:
IS 1391 : Part 1 : 1992 (RA Room Air Conditioners - Specification - Part 1 : Unitary Air
1999) Conditioners
IS 1391 : Part 2 : 1992 (RA Room air conditioners: Part 2 Split air conditioners
1999)
IS 2712 : 1998 (RA 1999) Gaskets and packings - compressed asbestos fibre jointing
IS 3588 : 1987 (RA 1999) Specification for Electric Axial Flow Fans
IS 3589 : 2001 (RA 2006) Steel Pipes for Water and Sewage
(168.3 to 2 540 mm Outside Diameter) - Specification
IS 3677 : 1985 (RA 2006) Specification for Unbonded Rock and Slag Wool for Thermal
Insulation
IS 4671 : 1984 (RA 2004) Expanded polystyrene for thermal insulation purposes
The air-conditioning system will be designed to operate continuously round the clock
twenty four (24) hours a day for all seasons of the year and to take care of heat loads
due to equipment, lighting, solar radiation, occupancy and inside design condition. The
following design data shall be considered for selecting and sizing of various equipment
of air conditioning and ventilation systems :
The temperature of the areas being ventilated by fresh filtered air supply system, push-
pull ventilation system or exhaust ventilation system shall not exceed 3°C above
ambient temperature at any part of the year. However, the ventilation system envisaged
shall be adequate to provide the desired ambience as required for the satisfactory
operation of electrical equipment / panels located in the ventilated premises. The same
(inside ambient temp.) shall be endorsed by the respective equipment / panel
manufacturer. If required, wet ventilation (i.e. air washer based pressurized ventilation
system) shall be provided to meet the inside requirement.
Detail heat load calculations of Ventilation and AC system shall be submitted first by
successful bidder for approval of the Client / Consultant before submitting any detail
engineering drawing. As a safety norm, all the steam piping has to be IBR approved and
the approval shall be obtained by the successful bidder.
Fire damper interlocking provision with fire detection system shall be considered for all
served electrical premises and susceptible fire hazard premises with the ACVS
equipment.
Unless otherwise specified in the technical specifications, all air conditioned premises
shall be maintained at 23±2 …C and 55±5 % RH.
All window glasses in air-conditioned premises shall be double glass type and airtight
double door entry provision shall be kept for these premises.
For improved water quality in refrigeration system, chemically treated water shall be
considered as make-up for corrosion protection. Necessary precautions shall be taken at
either side i.e. either the evaporator shall be selected to suit the available corrosion / pH
value of make-up water OR make –up water quality (pH / corrosion value) shall be
treated to match the fouling factor of given evaporator & condenser of VAM.
Chemically treated filtered water (soft water) shall be used as make-up to the expansion
tank and cooling tower basin.
Vol. – IIC, Section 02.00 ACVS Page 22 of 88
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TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
Chilled water pipe line shall be laid over ground. At the end of main supply and return
chilled water line, provision shall be kept with isolation valve for hooking up with
adjacent plant chilled water network. All pumps shall be vertical in-line pipe mounted
type with maximum RPM of 1500. Provision for monitoring of chilled water flow
quantity, temperature and served premises temperature shall be kept from central
control room station.
Fresh air supply as make up to AHU plant room shall be provided with pre-filter and
damper. AHU rooms shall be provided with necessary thermal (under deck) & acoustic
insulation.
Filter efficiency of pre-filter will be 90% down to 10 micron and fine filter will be 99%
down to 5 micron. High efficiency filter will be installed in the supply air duct at the
discharge end of blower / at AHU inlet.
Noise level generated in Central chiller plant, AHU room and duct line shall not be
transmitted to the served premises. Noise level in the served premises will not exceed
65 dB (A). Necessary acoustic insulation shall be provided to take care of the limit.
Noise level of individual equipment shall not exceed 85 dB(A) at 1m distance from the
equipment during peak load operation.
Local control of fan, pump, etc shall be provided near installation area for ON/OFF
operation as required.
Necessary handling facilities (electric hoist with monorails) shall be provided in chiller
plant room for handling pumps – impeller & motors, VAM inspection doors, etc.
Preferably exhaust fans of 900 rpm shall be provided in the chiller plant room &
compressor house.
All Equipment shall be provided with lifting attachments (wherever applicable) like
lugs, bolts, etc. to facilitate handling and lifting during erection and maintenance.
The strip heater will be installed in the supply air duct at the discharge end of blower for
dehumidification purpose and the strip heater will be interlocked with the blower unit to
prevent independent control/ switching of heaters. Safety thermostat shall be installed in
the duct line near strip heater for safety precaution. Strip heater box will comprise finned
heater, mounting plate, heater box/ casing made of 20 SWG G.I. sheet, cable terminal,
Vol. – IIC, Section 02.00 ACVS Page 23 of 88
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TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
terminal box with handle, 40x40x3 MS angle flange/ frame. Strip heater box will be
placed/ inserted in supply air duct. Safety thermostat will be mounted on strip heater
package to prevent overheating.
Pan type humidifier shall be installed in the AHU room for adding moisture if required
for critical control of R.H. Level. The humidification kit will comprise a SS pan,
immersion heaters (3 Nos.), immersion heater cover box with handle, 15 NB pipe
connection with float valve for make up water, 15 NB pipe connection for over flow, 15
NB pipe connection with valve for drain, thermostat, earth stud, etc. Over flow pipe and
drain pipe will be connected together after/ below the valve of drain pipe. The
humidifier will be insulated with 50mm thick mineral wool (T.F. quality). Safety
thermostat will be provided in the pan humidifier to prevent it from dry heating.
Centrifugal pump and cooling tower for condenser cooling shall be supplied for water-
cooled type condensing unit. Rubber/Neoprene gaskets will be used on all bolted joints as
a seal against water leakage.
Water pipe line will be of MS Heavy ( C ) Class as per IS 1239 : Part 1 : 2004 upto a size
of 150 NB and for sizes beyond 150 NB MS, spirally welded, 6mm thick & conforming to
IS 3589: 2001 (RA 2006) shall be provided. Pipe fittings up to 150 NB will be as per IS
1239 : Part 2 : 1992 (RA 2002). Fabricated fittings manufactured from pipes shall be
provided for pipes of size 200 NB & above.
Velocity of water in pump suction line and delivery line will be within 1.2 and 2 m/sec
respectively. Y- strainer will be provided in suction line of pump. Butterfly valve/ ball
valve will be provided in water pipeline at condenser inlet & outlet, AHU cooling coil inlet
& outlet, pump inlet & outlet. For multiple consumer points, balancing valve in horizontal
line shall be provided at chilled water return branch line. Pipe supports will be fabricated
from mild steel and coated with appropriate rust preventive primer and finish paint. Where
pipe and clamp are of dissimilar material a gasket will be provided in between. All piping
will be tested to hydrostatic test pressure of at least one and half times the maximum of
operating pressure for period of not less than 2 hours.
The following control, instrumentation and necessary interlock shall be provided for air
conditioning system :
d. Water flow switch /differential pressure switch with interlock and signal in chilled &
condenser water systems.
e. Dry bulb & wet bulb thermometer for all major air conditioned premises.
f. Thermostatic expansion valve, sight glass, refrigerant strainer.
g. Flow meter to measure chilled water flow and condenser cooling water flow rate
h. Flow control valve in chilled & condenser water line
i. Any other instrumentation not specifically mentioned above but required for the air
conditioning system will be indicated & provided by the Tenderer.
Central AC with chiller plant at ground floor shall be envisaged for the entire air
conditioning premises. Air conditioning shall be provided mainly by VAM based chiller
with standby 100% being provided by Screw Chiller of identical capacity. VAM based
chiller consists of VAM (steam based) chiller, steam condensate pump, chiller pump,
condenser pump, pump for de-superheating station, cooling tower & AHU. Chillers
shall be selected after considering 20% margin over the cooling load. AHU rooms shall
also be taken into account while evaluating the overall cooling load of the entire AC
system. AHU rooms, cooling tower shall be planned at the roof top. The expansion tank
duly insulated and complete with motorized valve, interlock with low & high level
switch, etc. shall be located at the highest elevation level with suitable approach &
platform for maintenance. The following tentative premises shall be considered for
central air conditioning system:
Sl.
Tentative Premises Facilities
No.
1. Control room / Control operator 2xAHUs (1W+1S) served through common
desk room chiller plant to meet inside condition of 23 ±
20C, 55 ± 5% RH
2. Electrical panel room, office, 2xAHUs (1W+1S) served through common
conference room, cabins, etc. chiller plant to meet inside condition of 23 ±
20C, 55 ± 5% RH
However, the distribution of loads for selection of AHUs shall be finalized during
detailed engineering keeping the inventory for similar AHUs, pipes, valves, air filters,
dampers & fire dampers in view.
Split type air conditioners shall be envisaged for isolated premises, if any which will
generally maintain a temperature of 23 + 2 deg. C.
The Vapour Absorption Machine based chilled water plant shall include :
• The unit comprising generator, absorber, evaporator, condenser, heat exchanger
tubes, refrigerant pipe line, steam & chilled water piping with valves & safety
• Ducting network with VAV box, damper, diffuser, acoustic and thermal insulation.
• Humidity control arrangement with strip heater, pan humidifier and humidistat.
• Make up air filter with damper in different AHU rooms.
In addition to the above, the standby packaged chilled water unit will be vapour
compression type chiller designed for continuous duty. Each package chiller unit will
essentially comprise of rotary screw compressor, shell & tube type water chiller,
refrigerant circuit, water cooled condenser, electric drives, instruments and controls
and other standard accessories assembled in steel cabinet. The compressor will be
semi-hermetic / hermetically sealed and mounted on anti-vibration pads &
dynamically balanced. Each chiller shall have multiple screw compressors with
independent refrigerant circuit.
Condenser shall be horizontal, shell & tube type construction dual refrigerant circuit
water-cooled type. Unit shall be equipped with integral finned type, solid drawn,
seamless copper tube of diameter approx. 19mm and thickness not less than 0.63mm.
The tubes shall have internal turbulator. Fins shall be made of Aluminium having 25
nos. per inch (min). Condenser shell will be constructed and tested in accordance
with section VIII, division I of ASME pressure vessel code. The shell shall be
capable to withstand refrigerant pressure of 300 psig, where as the tube side shall be
capable to withstand a water pressure of 150 psig. Cast iron water heads shall be
incorporated for easy removal, mechanical tube cleaning and/or tube replacement.
Condenser shall be provided with multiple pass to give optimum water velocity
through tubes combining efficient heat transfer and allowable pressure drop.
VAM shall be completely factory assembled and wired in a single package complete with
evaporator, absorber, two stage generator, condenser, heat exchangers, solution pump,
refrigerant pump, vacuum pump for purging, starter panel (starting control), PLC based
control panel (safety & operating controls), all necessary sensors/ instruments, internal
cabling and piping work. Solution & refrigerant pump drive shall be hermetically sealed.
VAM shall be supplied with full operating charge of eco-friendly refrigerant (water),
lithium bromide solution (with non toxic inhibitor) and octyl alcohol for purging. Lithium
Bromide and Octyl Alcohol shall also be supplied for one year consumption. The
machine shall be factory tested under operating conditions. The absorption machine shall
be horizontal shell and tube with unit shell which shall be horizontally divided into two
parts. The upper part of VAM shall contain the condenser and the low temperature
generator. The evaporator and the absorber shall be housed in the lower part. The high
temperature generator shall be provided either on the side of the machine or at the top
depending upon the type of the machine. The heat exchangers shall be horizontal shell
and tube type and fitted beneath the unit shell. The unit will be complete with all
necessary piping, valves, mountings, instruments, thermometers, etc. for normal and
satisfactory operation. Insulation of VAM unit shall be provided. The VAM shall be
double effect steam fired type with HTG having SS straight tubes as per job requirement
and availability of steam quality.
Vapour absorption m/c shall be chosen to operate normally with saturated steam in the
pressure range 0.5 to 10 kg/cm2(g) to deliver chilled water at 7 deg C with delta t of 5 deg
C (i.e. return water at 12 deg C). However, in specific cases, operation with Hot Water in
the temperature range 90 -135°C may be provided, if required.
Vapour absorption m/c shall be chosen not only to meet the full load design but also to
perform efficiently at lower loads and at lower condenser water inlet temperature
(particularly during winter season). Necessary condenser water temperature control shall
be provided. Tenderer shall furnish the inlet condenser water temperature range of their
machine.
Evaporator heat exchanger design shall meet the chilled water inlet & outlet temperature
required for air conditioning requirement as mentioned above in the job specification.
The following inputs are available for the purpose of steam based VAM system:
Temperature – 180 ◦C – 200◦C
Pressure – 12 kg/cm2
Flow – 2.5T/hr
Elevation of the header – 6 meter
Dia. of the header – 100 mm
Fouling factor for condenser & evaporator shall be 0.001 & 0.0005 hr-ft² °F/ Btu
respectively.
The evaporator portion and support structure should be painted with chloro-rubber paint.
High Temperature Generator with ‘U’ tube configuration for better thermal expansion
arrangement. High temperature and low temperature heat exchanger for improving cycle
efficiency. Sight glasses shall be fused type. Drain cooler to effectively cool steam
condensate & improve energy efficiency. Solution & Refrigerant pump with necessary
isolation valves. Imported high quality floats/relays for HTG & evaporator levels shall be
provided. All pressure and temperature gauges should be glycerin filled with shatter proof
glass and isolation valves for maintenance, calibration and replacement.
Pneumatically operated steam control valve complete with air set, regulator, valve
positioner, I/P converter, solenoid valve on air line complete in all respects shall be
provided. Compressed air lines shall be provided by the successful bidder as required for
AC system.
Following safety and controls will be provided with the vapour absorption machines:
Automatic capacity control system consisting of steam control valve and automatic
temperature controller shall be provided to control the refrigerating capacity in
accordance with the load requirement. Capacity control should be smooth, stable and
step-less from 100% to 20% load. Automatic control of chilled water outlet temperature
shall be provided by controlling steam flow rate.
Necessary instruction manual, P&I diagram, control panel drawing, GA drawing, civil
foundation drawing shall be furnished.
The steam flow control valve should be installed at a maximum height of 1m from the
floor.
VAM shall have connectivity for communication, data logging, history charts and mimic
to PC at remote location.
Vol. – IIC, Section 02.00 ACVS Page 29 of 88
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TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
The standby packaged chilled water unit will be vapour compression type chiller
designed for continuous duty. Each package chiller unit will essentially comprise of
rotary screw compressor, shell & tube type water chiller, refrigerant circuit, water cooled
condenser, electric drives, instruments and controls and other standard accessories
assembled in steel cabinet. The compressor will be semi-hermetic / hermetically sealed
and mounted on anti-vibration pads & dynamically balanced. Each chiller shall have
multiple screw compressors with independent refrigerant circuit.
Condenser shall be horizontal, shell & tube type construction dual refrigerant circuit
water-cooled type. Unit shall be equipped with integral finned type, solid drawn, seamless
copper tube of diameter approx. 19mm and thickness not less than 0.63mm. The tubes
shall have internal turbulator. Fins shall be made of Aluminium having 25 nos. per inch
(min). Condenser shell will be constructed and tested in accordance with section VIII,
division I of ASME pressure vessel code. The shell shall be capable to withstand
refrigerant pressure of 300 psig, where as the tube side shall be capable to withstand a
water pressure of 150 psig. Cast iron water heads shall be incorporated for easy removal,
mechanical tube cleaning and/or tube replacement. Condenser shall be provided with
multiple pass to give optimum water velocity through tubes combining efficient heat
transfer and allowable pressure drop.
With special tube arrangement and the partition plate allowing cooling water to pass
through the condensed refrigerant and thereby sub-cooling the liquid. This produces
higher refrigeration capacity without increasing the power consumption.
Cooler shall be Shell and tube type DX / FLOODED chiller with dual refrigerant
circuit.
Chiller shall be constructed from carbon steel plate with adequate number of baffles for
efficient heat transfer.
Copper tubes of minimum diameter 16mm shall be rolled in to grooves on tube sheet
for a water tight and air tight joint. Joints between the tube sheet and the shell shall be
water tight while those between the shell and boxes shall be airtight. Adequate sealing
gaskets shall be provided to prevent leakage of refrigerant and the infiltration of
moisture and air in to the system. Fouling Factor (water-side) 0.0001 hr-ft2F/Btu shall
be considered for design of cooler.
Cooler shell shall be capable of withstanding a pressure of 150 psig on shell side while
225 psig. on the tube side. Refrigerant shall pass through the tube while water through
the baffled shell. Refrigerant head is designed for proper number of passes to ensure
refrigerant pressure drop is within the limit and adequate velocity for proper oil
carry-over long with vapours.
The chiller assembly shall be thermally insulated with Armaflex / equivalent material of
50mm thick and finished with aluminium cladding.
Following controls and safety devices / accessories shall be incorporated in the chiller.
• Pressure gauges
Pressure gauge shall not be less than 150 mm diameter dial with appropriate working
range and be complete with shut off gauge cocks etc., duly calibrated before installation.
Pressure gauges shall be provided at the following locations.
• Thermometers
Thermometers shall be 150 mm dial type with capillary tube and protective sheets, duly
calibrated before installation.
The AHUs shall be of fabricated construction & draw through type. The housing/casing
shall be of double skin construction. The frame work shall be of extruded aluminium
profile frames and peralluman nylon glass fibre reinforced corner joints. Double skin
sandwich panels shall be fabricated from inside with 22g galvanised sheet steel and
outside with 22g high polymer polyester coated (pre painted) galvanised sheet steel with
protection films on top. Minimum zinc deposition shall conform to Grade 275 of IS
277: 2003. The 25 thk. panels shall be PUF injected with PUF density of 40 kg/m3 to
ensure high rigidity and sound attenuation characteristics. The unit sections shall be
mounted on galvanized sheet steel channel & aluminium die cast legs. Panels shall be
fitted to Al frame work with neoprene gaskets & screws. The framework of AHU casing
shall be assembled by means of reinforced nylon corners. Necessary supports shall be
provided to slide the coil in the drain pan. Outlet shall be provided on both sides of the
drain pan. The fan section of the casing shall be provided with access door. Aluminium
die cast / Chrome plated hinges & handles shall be used in access door. The AHU shall
consists of the following sections :
Filter section.
Cooling coil section
Fan section:
Filter section shall house 48-50 mm thk. pleated filters having cleaning efficiency level
more than 99%. These filters shall be vertically arranged in the frame and all mounted
directly on AHU for ease of removal.
Cooling coil section shall have chilled water cooling coils constructed with copper tubes
and fins of aluminium. Thickness of Cu tubes shall be minimum 0.75 mm. Fin spacing
shall be minimum 10 fins per inch and minimum thickness of fins shall be 0.16 mm.
The fins of the coil shall have a mild ripple with die formed directional guide channels
to improve heat transfer efficiency. Cooling coil header shall be of GI. Chilled water
Vol. – IIC, Section 02.00 ACVS Page 32 of 88
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TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
coils shall be provided with suitable vent and drain connections. Drain pan shall be
fabricated from minimum 22 G stainless steel sheet and stainless steel nipple for drain
connection. Necessary slope shall be provided to facilitate fast removal of condensate.
Drain pans shall be thermally insulated. The entire assembly shall be mounted on PUF
insulated bottom panel. Condensate drain pipe of required length with sealing loop shall
be provided and insulated. The drain from drain pan shall be connected to floor drain.
Air velocity through cooling coil shall not exceed 2.5 m/sec and pressure drop across
the coil shall not exceed 15 mmWC. Water pressure drop through cooling coil shall be
limited to 5 mWC. Normally AHUs shall have 6 rows of cooling coil.
Fan section shall house centrifugal fan(s) which shall be forward curved, multiblade
double width double inlet type. Impeller blades shall be fabricated from heavy gauge
galvanised sheet steel or MS with spray galvanized. The wheel & housing shall be
fabricated from heavy gauge galvanised steel. The fan section shall be mounted above
the coil section. Fan speed shall not be more than 750 RPM. Flexible connection &
volume control damper (opposed blade type) shall be provided at fan outlet.
Blower fan shall be statically and dynamically balanced as per ISO1940 Gr 2.5. The
first critical speed of the rotating assembly shall be at least 25% above the operating
speed. The motor & blower assembly shall be isolated from the main frame by means of
spring. Motor & fan assembly shall be mounted on base frame and fixed on anti-
vibration rubber mounts. Motor shall be mounted on a slide rail to adjust the belt
tension. Fan shall be coupled to motor by V belts. V belts shall be provided with guards
that do not impede the air flow to the fan inlet. Fan static pressure shall be minimum 60
mmWC or more (as required based on pressure drop calculation). All the AHUs shall be
selected on the basis of min. 500 CFM/TR.
Temperature control in AHU shall be provided by modulating the chilled water flow in
the cooling coils by 3-way mixing valve. A bypass line around 3 way valves shall be
provided. Temperature switch and transmitter for monitoring of chilled water and served
premises temperature shall be provided. AHUs shall be offered with dehumidified air
quantity of at least 500 CFM/TR.
The capacity of the cooling tower shall be adequate to take care of the entire cooling
water required for the air conditioning plant.
The cooling tower with RCC basin shall be mounted on masonry pillars on the roof of
the building.
Cooling tower capacity shall be adequate to cool water basin temperature up to maximum
29oC as per prevailing ambient condition to meet the condenser cooling requirement of
screw chiller.
Cooling towers shall be provided with the following items and accessories :
• Ladder : Galvanised steel ladder with safety cage & hand railing up to the top of
tower to access fan, motor, nozzles, etc. Inclined to 300 to the vertical.
• Eliminators shall be provided in removable sections and installed in the cell of the
tower. The number of deflections in the eliminators shall be so arranged as to
limit the drift loss to within 0.01% of the circulated water.
• Level switch at cooling tower basin (to be interlocked with pump)
• Make up connection with float valve (float made of copper), back up ball valve
• Quick fill connection with ball valve
• Overflow connection
• Drain connection with ball valve
• GI wire mesh 18 gauge strainer
• Equalizing line of cooling towers with isolation valves
• Cooling tower basin (for chilled water plant) shall have minimum 5 minute water
holding capacity (of circulation water volume).
• Arrangement for handling fan – motor.
The insulation of water piping, air-handling units, ducting, chillers etc. shall be carried
out to maintain proper temperature of fluid / vapour in the conduits & to prevent surface
condensation on cold surfaces.
The thermal conductivity of the material shall not exceed 0.04 W/m deg. C. at 10 deg. C
mean temperature and density should not be less than 60 kg/ m3. Thickness of the
insulation shall be as specified below for the individual applications. The insulation
material can be readymade pipe section or precut sheets.
The thermal conductivity of the material shall not exceed 0.04 W/m deg. C. at 10 deg. C
mean temperature and density should not be less than 40 kg/ m3. Thickness of the
insulation shall be as specified below for the individual applications. The insulation
material can be readymade pipe section or precut sheets as per application. The PUF
shall be CFC/HCFC free.
Ducting:
The air handling ducts shall be insulated with closed cell Nitrile rubber / Polythene with
density 60±2 kg/m3. Duct insulation thickness shall be as follows :
Cold adhesive or equivalent can be used for setting the insulation on the pipe/duct.
Vol. – IIC, Section 02.00 ACVS Page 36 of 88
© 2020 MECON Limited. All rights reserved.
TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
The air handling ducts shall be insulated with resin bonded glass/mineral wool with
density not below 48 Kg/m3 with polythene back hessian on outer side. Duct insulation
thickness shall be as follows :
Clean the surface with wire brush to make it free from rust etc. Apply two coats of hot
bitumen 85/25 to the surface @ 1.0 Kg/m2 for first coat & in patches for second coat.
Wrap the duct with insulation blankets of the specified thickness. Apply PBH layer on
the outside and reinforce it by tying GI wire of 0.5 mm at interval of 450 mm.
Duct in outdoor areas exposed to weather shall be covered with 24 SWG Aluminum
sheet bent true to shape and secured with self-tapping screws and over lapped joints
sealed with Loidseal – 94.
Acoustic Lining:
The first 7 meter length of duct starting from each fan outlet shall be provided with
insulation for acoustic purposes. The insulation material shall be as specified under
“Insulation materials” above. Then it shall be covered with 0.56 mm perforated
Aluminium sheets.
Application Procedure:
The duct surface shall first be cleaned from inside. The insulation boards shall be
wrapped in Glass Cloth of 7 mil thick with ends stitched. The boards shall be fixed
inside the duct. The insulation shall then be covered with 0.56 (24 SWG) perforated
Aluminum sheets.
The sheet and the insulation, shall be secured to the duct by means of cadmium plated
bolts, nuts and washers and the ends should be completely sealed off so that no
insulation material is exposed.
Insulation material shall be resin bonded glass wool/mineral wool of density 48 Kg/m3
of 50 mm thickness.
Application Procedure:
Fill each rectangle with 50 mm resin bonded glass/mineral wool wrapped in glass cloth.
Then tie with 24 SWG GI wires at 300 mm intervals. Then cover with 24 SWG (0.56
mm) perforated Aluminum sheet having 3 mm perforations at 6 mm C – C. Overlap all
the joints and provide beads of 25 mm by 1.5 mm MS flat.
The ducting network comprises ducting work, duct line dampers, down comer & supply
air diffuser with VAV box for HVAC system, supply air grill/ adjustable louver grill
duct supporting arrangement, flexible connections, etc. All GI / Aluminium ducting
work for airflow shall conform to IS 655: 2006. Galvanised steel sheet conform to IS
277: 2003 grade VII (i.e. zinc coating @ 200g/m2). As per job specification
requirement ventilation duct may be fabricated from steel sheet conforming to IS 2062
:2006.
Ducting work
Ducting work consists of main duct, branch ducts, bends, reducers, joints, access doors,
etc. Duct work shall be complete with flanges, gaskets, stiffeners, fasteners (nuts, bolts
& washers), hangers, etc. as required. Minor modification of ducting network may be
required to suit site condition. GI Ducts shall be fabricated at site to match with site
condition. All ducting work shall be properly reinforced to prevent sagging, buckling or
vibration. GI Ducting shall be provided with joints at 2.5 - 3m interval conforming to IS
655: 2006 as and where required. In case of flanged joints, the flanges shall be of angle
iron type riveted with GI sheet on duct perimeter. Flange joints should be made air tight
with use of felt gaskets. Duct supports shall be provided to keep the ducting in position
in aligned condition. Measuring hatch for measurement of flow / pressure shall be
provided in ducting network at convenient locations. For proper distribution of air in the
premises, supply air grills (adjustable louver grills) with volume control dampers shall
be provided in the ducting work for ventilation system and supply air diffusers with
volume control damper shall be provided in the ducting work for air conditioning
system. Sizing of the duct shall be done for pressure balancing as well as to
maintain the air velocities in the ducting work as given below: -
Outside exposed supply/return air duct and indoor AC duct shall be thermally insulated
to avoid heating up of cold air duct and condensation. Ventilation duct which are
exposed to atmosphere shall be also thermally insulated with sand cement plaster finish.
Supply air diffusers (AC / ventilation) shall be provided at the supply air duct @ not
exceeding 3m centre to centre distance inside the served premises.
Joints : In line with IS 655: 2006 guide lines the type of transverse joints shall be
followed unless otherwise specified in job specification :
Sealing: All construction joints and duct seams shall be reasonably sealed with
bituminous cold emulsion or equivalent vapour seal.
Bends : The interior of all ducts shall be smooth for free flow of air. The radius to bend
shall not be less than 1.5 D. Turning guide vane shall be provided in all large duct bends
and bends with radius less than 1.5 D for proper air flow.
Access door : All main ductwork shall be accessible throughout using tight fitted
hinged access doors, provided with sponge rubber gaskets. Angle joints shall be
provided with felt or rubber gaskets for leak-tightness of the joints.
Any other place if envisaged by the owner about its essentiality during drawing
approval or construction period. In case access doors are to be installed in the insulated
ducts, the access door panel should be insulated too with overlapping, such that it can be
Vol. – IIC, Section 02.00 ACVS Page 39 of 88
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TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
operated without damaging the duct insulation and there should be no condensation
either on the access doors or on the duct when the plant is in running condition.
Adjustable louvers grill (Supply air grill) with volume control damper for
ventilation system:
1.25mm MS sheet shall be used for the manufacture of grill. All grills shall be true to
shape and shall be checked with a level gauge before being secured in position. No
distortion or warping is permitted.
All duct mounted grill shall be complete with rubber gaskets and flanged holding
frames of suitable design for the intended installation. They shall be mounted on collar
extending from the duct. No part of grilles shall project into the main duct. The
adjustable louver grill shall be provided with volume control damper as well as double
deflection flap/ grill for direction control.
Supply air diffuser (SAD) with volume control damper / VAV box for AC System:
SAD with VCD shall be provided where no variation of load is expected (Control room,
electrical panel room, drive room) and SAD with VAV box shall be provided where
there is load variation like in conference room, etc. Bidder shall ensure that automatic
temperature control at user end shall be governed.
These shall of the low velocity variable air volume boxes without re-heat coils and shall
be of open protocol as marketed by a firm specializing in this field. The unit shall be
complete with damper, airflow ring, and solid-state electronic controls to provide
accurate room temperature control automatically with respect to the load available in the
premises at any point of time. The damper shall be aerofoil type construction with
Vol. – IIC, Section 02.00 ACVS Page 40 of 88
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TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
bearings. Boxes shall be supplied with all internal attenuation treatment and acoustical
damped casing necessary to achieve the required noise criteria. Casing shall be of 22G
GSS minimum fitted with a completely sealed, easily removable means of access to all
internal parts. Access to all boxes must be from the underside only.
The actuator shall be of 24V AC Bi-directional, direct coupled to the damper shaft. The
required transformer to step down of the voltage range from 230V to 24V shall be part
of the unit. The unit shall be complete with transformer, access panel and other
accessories as per the standard. The noise level shall be less than 35Dba.
Maximum allowable static pressure to the boxes for its satisfactory operation shall not
exceed 0.10WG, otherwise fan and motor selections may be affected. Boxes shall be
able to reset any air flow between 10% and the maximum air quantity that the boxes can
handle without changing orifices or other parts. Air quantity limiters will not be
accepted. Under shut-off conditions, all boxes shall not have air leakage more than 2%
of the maximum air quantity at 75mm static pressure.
The VAVs shall be used in standalone mode complete with its own temperature sensor
and controller and shall perform the function of maintaining the temperature and airflow
automatically as per the load. All boxes shall be electrically controlled. The boxes shall
be pressure independent. VAV Box shall have provision to support from floor/ wall/
ceiling and in vertical/horizontal condition.
Return air duct shall be provided above false ceiling in the served premises and AHU
plant room. The return air grill of suitable size shall be provided at the AHU plant room
side face for smooth flow of return air. The air supplied in the served premises shall
return above false ceiling through the return air duct of the served premises. From there,
it shall pass into the AHU plant room. The return air grill shall be painted with
appropriate colour to match with the colour of the false ceiling. Return air grills shall be
of extruded aluminum powder coated / Anodized aluminum.
Insulation: Sheet metal duct shall be acoustically and thermally insulated as per
requirement. For details of insulation refer respective equipment specification.
Hangers & supports for ducting: All duct work shall be provided with adequate
supports as required to ensure rigid support and to prevent vibration. The fixing and
supports interval shall not exceed 3 meters. Hanger rods having U-bend at one end and
Vol. – IIC, Section 02.00 ACVS Page 41 of 88
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TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
threading at other end shall be hung from the ceiling by anchor fasteners / expansion
bolts. Duct angle supports from brick wall/RCC wall/ structural wall shall be grouted /
welded to suit site.
Make up air filter with damper: Make up air for AHU will be drawn from ambient
through filter and volume control damper.
Self Acting Damper: Self acting dampers shall be provided to maintain pressurisation
inside the ventilated premises. The damper shall be used in the premises being served
with pressurized plenum ventilation system. The damper shall be multi-blade type made
of Aluminium flaps of not less than 24G thickness and GI frame of 18G. These shall be
designed such that these shall operate when the pressure inside the premises exceeds 2-3
mm WC. It shall be possible to operate in fully open or partial open positions.
The pumps shall be designed, manufactured and tested as per following applicable IS
standards (IS 5120: 1977 (RA 2001), IS:1520-1980, IS:5120-1977, IS 9137:1978 (RA
2002)).
In case any other international standards are used, the same shall be subject to approval
of the Purchaser and the pumps shall be suitable for the duty conditions and capacities
as indicated in the job specifications.
The centrifugal pumps along with their auxiliary equipment shall be suitable for the
required duty conditions and shall be designed and manufactured for continuous duty at
full load. All the pumps shall be capable of developing the required total head at rated
capacity for continuous operation. The pumps shall operate satisfactorily at any point on
the H-Q characteristic curve over a range of 25% to 130% capacity or capacity
corresponding to 75% of the total head whichever is lower.
Capacity vs discharge pressure curve for each pump shall preferably be continuously
drooping from the shut-off point to the rated operation point and be suitable for parallel
operation. The pumps shall be designed to avoid cavitations at any of the operating
points.
The required duty range for a pump shall be on stable portion of its head-capacity curve
close to the best efficiency point. The head developed at the best efficiency point shall
be close to the required differential pressure so that throttling is not required at pump
discharge.
The vertical centrifugal pump sets shall be supplied with flange mounted vertical
motors, motor stool, base plate, coupling, column pipe, delivery pipe, suction strainer,
companion flanges, gaskets, bolts, nuts, washers, etc. The equipment and auxiliaries
shall be designed for quick and economical maintenance. The equipment shall be easily
dismantleable without disturbing the suction and delivery pipe connections.
The equipment design shall incorporate provisions for reduction in noise level.
The rotating elements of the pumps shall be checked for critical speed in bending as
well as torsion. The critical speeds shall be at least 30% above the normal speeds for
units with flexible shafts and at least 20% above the maximum operating speed in case
of stiff shafts. All passages inside the pump casing and impellers, which may be
inaccessible to machining, shall be ground to a smooth finish as far as practicable.
All pumps shall be centrifugal vertical inline type pipe mounted with maximum RPM of
1,500. However, mono-block type pump for wet ventilation system only in case on non-
availability of vertical inline pump may be provided.
Material of construction
Casing - C.I
Impeller - Bronze
Bearing Bracket - C.I
Shaft protection sleeve - Bronze
Wearing ring - Bronze
Shaft - EN8
Common base frame for pump & motor - M.S
The direction of rotation shall be clearly marked either by incorporating it on the casing
or by an arrow on a separate metal plate securely fitted to the casing.
A stainless steel name plate of 2 mm thickness shall be provided and securely attached
by stainless steel pins at an easily accessible point on the pump. The plate shall be
stamped with the following minimum information :-
a) DESIGN CAPACITY
b) TOTAL HEAD
c) SPEED
d) MOTOR RATING
e) MODEL NUMBER
f) MANUFACTURER’S SERIAL NUMBER
g) WEIGHT OF EQUIPMENT
h) TAG NUMBER
The total head-capacity curve shall be continuously rising towards the shut-off. The
shut-off head shall be at least 110% of the total head.
The velocity of vibration shall be within acceptable limit as per IS standard.
The power rating of the pump motor shall be larger of the following :
b) For parallel operation, motor rating should be sufficient enough for running of
single pump also.
The casing shall be of cast iron and shall be designed for a pressure not less than the
shut-off pressure at the highest operating speed plus the maximum pressure that may be
encountered at the pump inlet. In addition, CI casing shall have corrosion allowance of
not lower than 3 mm. The casings shall be smooth, free from blowholes, cracks, fins
and other imperfections and thoroughly cleaned. Standard hydrostatic test shall be
conducted on the pump casing with water at 1.5 times the maximum discharge head or
twice the rated discharge head whichever is higher. The hydrostatic tests on the casing
shall be conducted for a minimum duration of 30 minutes.
Impeller shall be of bronze. Impellers and balancing drums (if provided) shall be
statically and dynamically balanced. Dynamic balancing shall be at the operating speed
of the pump. For multi stage pumps, all the impellers shall be assembled together for
balancing. Provision shall be made for adjusting the clearance between the impeller and
the casing to compensate for wear. The impeller shall be keyed or screwed on to the
shaft in such a way that it does not come-out due to reverse rotation of the pump.
The shaft shall be of EN-8 or equivalent and shall be designed for critical speed. The
ratio of critical speed to speed of shaft shall be not less than 1.3 for solid shafts. The
deflection in line shaft shall not exceed 1 mm per meter of length. All shafts above 150
mm diameter shall be ultrasonically tested. Shafts shall be checked for endurance and
strength. Change of sections in shafts if considered shall be made with due allowance
for stress concentration. Shafts shall be machined to close tolerance for mounting on
impeller bearings, shaft seal, shaft sleeve, shaft coupling etc. The magnitude of shaft
deflection at the face of the shaft seal shall not exceed 50 microns.
Long shafts shall be supported on bearings at 3m centre or less. Shafts shall be easily
accessible throughout their lengths and shall be designed as far as practicable in
interchangeable lengths. All steel shafting 150mm or less in diameter shall be hot rolled
and turned, forged and turned, cold rolled or cold drawn. All shafting above 150mm in
diameter shall be forged and machined to size. All forged shaft shall be annealed or
normalized before machining and then heat-treated, if necessary.
For vertical pumps when coupled with solid shaft motor, the coupling shall be of rigid
adjustable type. Removable coupling guards shall be supplied and mounted. Guards
shall be sufficiently heavy and rigid to provide adequate personnel safety.
Shaft seals shall be provided to prevent leakage out of or into a pump over the range of
specified operating conditions. The seals shall be suitable for variations in inlet
conditions that may prevail during start-up and shut down. They shall be accessible for
inspection and replacement without disturbing any part of the installation. An adequate
drain shall be provided so that liquid cannot collect on the drive support.
Coupling shall be properly keyed in place and the cylindrical fit shall allow simple
removal of the coupling in the field. Removable coupling guards shall be supplied and
mounted. Guards shall be sufficiently heavy and rigid to provide adequate safety for
working personnel.
Two bearing assemblies shall be provided, one within the frame to carry radial load
only and the other to carry both radial and axial thrust. Bearings shall be of
manufacturer’s standard design. Water lubricated sleeve type bearings may be used.
Suitable thrust bearings shall be provided in the pump to take total thrust of the pump
including hydraulic thrust. Vertical motor shall be provided with separate thrust bearing
to take care of its own axial thrust. Motor thrust bearing shall be designed without water
cooling arrangement. Suitable tapped holes shall be provided for refilling of oil in the
bearing housing.
All the vertical pumps shall be provided with separate thrust bearings with proper
lubrication and cooling facilities as required so that the thrust and other vertical loads
due to the moving parts are not transferred to the prime mover.
All pumps shall be supplied with sturdy base plates as per manufacturer’s standard.
Base plates and pump supports shall be constructed so rigidly and the unit so mounted
on pipes as to minimize misalignment due to piping strain, internal differential thermal
expansion, etc. Base plates shall be fabricated from MS channels.
Plate flanges having raised face shall be provided at suction and delivery side of pumps
and they shall be of mild steel and conform to table 17 of IS: 6392-1971 (R.A.1988).
Slip on raised face flanges to 150 Lbs. class conforming to ANSI B16.5 shall also be
acceptable. Black bolts and nuts conforming to IS 1362-1992 shall be provided for the
companion flanges. CAF gaskets of 1.5 mm thickness conforming to IS: 2712-1979
(R.A. 1994) shall be provided for the companion flanges.
Following data sheet shall be followed for the pumps :
Sl. No. Parameters Details
1 No. of Pumps To be included by Tenderer
2 Application Industrial water
11 Duty Continuous
13 Material of construction
a Casing/Bowl CI FG 260
c Impeller Bronze
d Shaft En8
f Strainer MS-Galvanised
02.22 Valves:
Depending on the layout, the Tenderer will provide valves wherever required for ACVS
systems. All valves shall conform to applicable Indian Standards. All flanged valves
and pipe fittings will be supplied with matching flanges, bolts, nuts and gaskets. All
valves will be suitable for required working pressure of the system served.
Strainers will be provided in the condenser water supply / inlet line, washed air systems,
etc. Bypass line with valves will be included to facilitate cleaning the strainer without
affecting the functioning of the unit.
Vol. – IIC, Section 02.00 ACVS Page 46 of 88
© 2020 MECON Limited. All rights reserved.
TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
Gate valves will be provided at pump outlets & at tank outlets whereas butterfly valves
shall be provided at pump inlets.
For dust suppression systems, pressure relief valves shall be provided at pump outlet to
divert water back to the tank in case downstream usage of water is reduced. Butterfly
valves shall be provided in branch headers to operate a particular group of nozzles.
Globe valves shall be provided on nozzle headers to control the flow through each
nozzle.
Butterfly valve
Butterfly Valves shall be provided in water line of size 65 NB and above and ball valve
shall be provided for pipe size below 65 NB.
The valves shall be provided with integrally moulded & bonded body liner to provide
perfect seating and complete isolation of body material from fluid. The body liner shall
provide the seating to valve disc, primary seal to the stem & gasket joint with matching
pipe flanges. Valves shall be provided with self locking lever operation from open to
fully closed position with intermediate positions marked on the indicator plate mounted
on the top flange. The valves shall conform to BS 5155 / IS 13095: 1991, RA 2003.
Extended valve shaft shall be provided so that the lever can be operated without any
obstruction on the insulated pipes. Gear operated valves shall be provided for sizes
more than 150 NB.
Ball Valve
The ball valve shall be of 3 piece design, socket welded type and be supplied with
200mm length of pipe on both sides.
Gate Valve
3. Bonnet Bolted
4. Spindle SS as per AISI 410
5. Disc Cast iron as per IS:210-1993 (RA 1999),GR 200
6. Body seat ring & SS as per AISI 410
Disc facing ring
7. End connections Below 50 mm - Screwed. 50 mm & above flanged end, to be
drilled as per ANSI B.16.5
8. Pressure rating As per system requirement
9. Flange facing Flat Face
10. Manufacturing std. IS:778, 1984, RA 2007
11. Bolts & nuts Black Hexagonal bolt with nut as per ASTMA 307 Gr B.
12. Gaskets Compressed Asbestos Fibers to IS 2712: 1998 (RA 1999), 1.5
mm thick
13. Hand wheel CI Gr 200 as per IS : 210 – 1993 (RA 1999)
14. Packing Asbestos
15. Companion ANSI B16.5 Class 150
Flanges
16. Hydrostatic testing As per relevant IS & Pressure rating of PN 1.6
17. Test certificates For Physical/chemical analysis & metallurgical tests for body
parts , Hydro testing
18. Service Re-circulation water/ Make up water/chilled water
Globe Valves
1. Type Dual plate check valve with two springs hinged on a central
hinge rod / Swing check type
2. Body SG iron / Cast iron as per IS: 210-1993 (RA 1999), GR. 200.
3. Body liner Nitrile rubber/ EPDM
4. Cover SG iron / Cast iron as per IS: 210-1993 (RA 1999), GR. 200.
5. Hinge Cast iron as per IS: 210-1993 (RA 1999), GR.220.
6. Hinge pin HT brass IS 320: 1980 (RA 2006) HT-2
7. Body Seat Ring & IS 318: 1981 (RA 2001) Gr 2
Disc ring
8. Disc ASTM A351 Gr CF8 / CI as per IS: 210-1993 (RA 1999),
Gr.200
9. Gasket CAF gasket as per IS 2712: 1998 (RA 1999) of thickness 1.5
mm
10. End connections Flanged end, drilling as per ANSI B16.5
11. Pressure rating As per system requirement
12. Manufacturing Std IS:5312(Part-1)-2004 / BS-5153 1991
13. Bolts & Nuts Hexagonal type as per IS:1367-1967 Cl.-4.614.4
14. Companion ANSI B 16.5 class 150
Flanges
15. Hydro static testing As per IS : 5312 Part-1 -2004 / BS 5153 (1991) and pressure
rating of PN-1.6
16. Test certificates For Physical/chemical analysis & metallurgical tests for body
parts , Hydro testing
17. Service Water / chilled water
Dry panel type air filter shall be of high efficiency cleanable type, constructed out of
HDPE (6 ply) supported by layers of GI wire gauge. It shall be corrugated to the depth
of filter casing in order to increase the ratio of filtration area to frontal area. It shall be
covered by strong GI frame (14G) and shall have space to ensure uniform distribution
of air. Filtering panel shall be of standard size which can be mounted on angle frame in
multiple number as per capacity of the fan. Face velocity of air shall not exceed 1.5
m/sec. The resistance of air filter shall not exceed 10 mmWC when dirty. Efficiency of
the normal air filter shall not be less than 90% down to 10 microns unless otherwise
specified in the job specifications. Cleaning efficiency of the high efficiency air filter
shall not be less than 99% down to 5 microns unless otherwise specified in the job
specifications. Panel type air Filters testing shall conform to IS 7613 : 1975 (RA 2001).
Steel tank of suitable capacity fabricated from 6mm thick MS plates (as per IS:2062) in
welded construction shall be provided at the highest point of the chilled water circuit for
chilled water expansion cum make up. This tank shall be complete with all accessories
like motorized ball valve and float valve for make up connection, quick fill, drain
overflow, low & high level switches, approach, platform, ladder, etc. Tank shall be
thermally insulated and aluminum cladded from outside and Zinc coated from inside.
Grade of Zn coating shall be 350g/m2. The tank capacity shall be 20% more than the
required volume of chilled water.
Split air conditioning unit shall comprise of two sections - Indoor and Outdoor. Indoor
section shall comprise of cooling coil, fan, supply air grill, filter. Outdoor section shall
comprise of air cooled condenser, condensing fan, hermetically sealed compressor.
Sealed refrigerant piping shall inter connect indoor and outdoor sections. Outdoor unit
shall be installed in open space for easy heat dissipation from condenser. Indoor section
shall be ceiling suspended or wall mounted type as per job specification requirement.
Remote control unit, thermostat and other standard accessories for successful
installation of split type air conditioner shall be included in the scope of successful
tenderer. Split air conditioner unit shall conform to IS 1391 : Part 2 : 1992 (RA 1999).
Eco-friendly refrigerant shall be used and the rating of the AC unit shall be 3 star
minimum.
02.26 Ventilation :
Depending upon the specific requirement, the premises envisaged in the project shall be
provided with either exhaust ventilation or pressurized ventilation. The system design
will take into account the requirement of air change as well as excess heat removal.
Filters will be provided with pressurized systems. The details and types of system
proposed are indicated in the equipment schedule.
Air Washer
Air washer unit comprises intermediate chambers at inlet and outlet and cell deck pad
chamber with water tank. Adapter section shall be provided for connecting air washer
unit with other equipment. There shall be 2 pumps (1W+1S) for the wet section. The
evaporative cooler shall be a self contained, single skin housing unit consisting of MS
intake louver of 75 mm deep with bird mesh, dry filter section, wet section and fan
section. The dry filters are 6 ply HDPE as specified. The wet section shall consist of
cooling media, water delivery system and sump including piping. The fan section shall
consist of fan with motor, drive arrangement to deliver specified air volume against
specified static pressure.
Housing
The housing shall be constructed from 16G GSS whereas the tank shall be of SS304.
Hinged access panel shall be provided in the fan section of the housing on both sides.
The access panel shall be gasketed or formed to preclude air or water leakage into the
interior of the housing. The opening shall provide easy access to the blower to allow for
service of the motor, belt adjustment, bearing and possible shaft replacement. The
housing shall be airtight and waterproof.
The wet section shall consist of a sump, sides and top. A side lift – off or hinged panel
for media access and service of the float valve assembly for make up water shall be
provided. Removal and replacement of the media can be made through either a side lift
off panel, top removal, intake or discharge side of the section as the case may be . The
wet section shall be mechanically attached through the frame work to the fan section
housing and shall be supported across it’s entire width.
Internal components of the wet section shall be cooling media, water delivery system,
internal plumbing including a header pipe, make –up water, overflow and drain fittings.
Fan Section
The fan shall be heavy duty centrifugal type, DIDW backward curved impeller blades
with non- overloading characteristics and shall be capable of delivering air volume at
external static pressure as per requirement. The fan shall be AMCA certified for
performance, noise level with balancing grade of G6.3. The fan shall have solid, ground
and polished C45 steel shaft with self-aligning type bearing on both ends.
Vibration isolation shall be provided under the fan and motor and shall be of spring
type. Isolators shall be selected for minimum deflection. Flexible neoprene rubberized
steel impregnated connection shall be provided between the fan discharge and the
housing at the outlet duct connection.
Wet Section
Sump construction in wet section shall include TIG (fusion) welded corners and joints.
The sump shall be leak proof without the use of fillers, sealants or coatings. A media
support channel shall be included. This channel shall extend across the full width of the
media. The channel shall provide a minimum of 50% open area for water to flow freely
from the media into the sump.
An air bypass inhibitor plate shall be provided from the intake bottom of the media and
designed to preclude any untreated air flow under the media.
Stainless steel couplers with female pipe thread shall be welded into the sump and side
to provide for make-up water, overflow and drain. Make up, overflow and drain
connection of suitable size shall be provided.
Water distribution system shall be pump re- circulating system with mechanical float
valve assembly to maintain water level in the sump. A bleed – off system shall be
provided. Bleed- off rate shall be minimum of 20% of evaporation rate. Pump shall be
sized to deliver water flow rate at the head and pressure required. Flow rate shall be
determined at three (3) times the evaporation rate plus the bleed-off rate. Pump shall be
vertical submersible type of SS construction. One working plus one standby pump shall
be provided for each air washer.
Media access and removal shall be accomplished through a removable side or top panel
provided for this purpose or from the intake or discharge side of the media by removing
retaining rails provided for media support and removal purposes as specified.
Dry Filters
A Dry filter stage will be provided to cover the entire intake face area of the cooling
module. Filters are extended surface, pleated type with 90% average dust arrestance
efficiency, 2” thick cleanable type with maximum velocity of 2 m/s. Filters shall be
removable from the intake side of the frame using bracketless lift and remove rack
system or side removable from a hinged panel provided for this purpose.
Low water level pump protection
A low water level protection system with float type level switch shall be used to
provide dry run protection for the pump.
Magnehelic Gauge
Magnehelic differential pressure gauge shall be provided to measure the pressure drop
across the cooling media to indicate the change in the resistance to air flow which
relates to the cooling media condition. The detector tubing shall be placed immediately
upstream and downstream of the media. Gauge shall be mounted externally on the unit
for manual reading of the pressure drop.
Generally the fans shall be of limit load design. Centrifugal Fan design shall conform to
IS 4894: 1987 (RA 1999). The fan shall be provided with drive motor, drive
coupling/V-belt, belt pulley, belt guard, fan inlet and outlet flexible connections, Guide
plate (to prevent direct contact of flexible fabric with air flow), slide rails, foundation
plates, gaskets, base frame, vibration isolators, Anchor / foundation bolts and nuts, fan
inlet protection screen and other standard accessories. In case standby fans or multiple
working fans are connected to the same duct line, fan outlet dampers shall also be
provided. All these items/materials and accessories shall be supplied with the fan.
The fan shall be of rugged steel construction, industrial duty type and suitable for the
proposed project/plant. Capacity and static pressure of fan shall be as per job
requirement. Fan housing shall be of welded construction and provided with flanges at
inlet and outlet sides for duct connections. The housing shall be provided with lifting
eye for ease of handling and bolted type access door. The equipment shall be designed
to permit ease of access during inspection, maintenance and repair.
The fan unit shall be free from undue noise and vibration during operation; normally the
fan speed shall not be more than 1500 RPM.
The fan shall be both statically and dynamically balanced as per ISO:1940. In general
HVAC system application balancing grade shall be of 6.3.
Casing and inlet box shall be fabricated from mild steel (IS 2062: 2006) plate with
continuous welded joints and external stiffening to prevent vibration. Flanged, bolted
and gasketed access doors are to be provided in the equipment scroll and inlet box. The
casing and inlet box of each equipment / fan shall be split with bolted flange joints to
allow for removal of the impeller and shaft without removal of installed connecting
ductwork. The casing, inlet box, scroll and impeller shall be suitably designed to take
care of corrosive environment.
Shaft seals shall be provided at the casing and the inlet box. The housing shall be fitted
with a bottom drain, not less than 50 mm dia. The equipment units and drive motors
shall be assembled on a common structural steel base plate wherever practical, to ensure
mounting rigidity.
The fan impeller may be backward curved for clean air application. The impeller shall
be of welded steel, designed for heavy duty and having non-overloading (limit-load)
power characteristics. The first critical speed of the rotating assembly shall be at least
25% above the operating speed.
Fans for ventilation systems shall have following minimum thickness of materials for
different parts unless otherwise specified :
Casing : 3.15 mm
Back plate : 4 mm
Impeller : 2.5 mm
Casing : 4 mm
Back plate : 6 mm
Impeller : 3.15 mm
Shaft
Shaft shall be steel bar stock or forging made of material conforming to EN 8 and
machined all over. The shaft with equipment impeller and half coupling mounted is to
be dynamically balanced.
Drive Coupling
The fan shall be directly driven. The drive coupling from the motor to fan shaft is to be
of flexible type suited for heavy duty and industrial application. A protective guard is to
be fitted over exposed drive shafts and coupling. Belt drive may be allowed only in case
of ventilation fans on specific approval of purchaser / consultant.
Bearings
The bearings are to be outside of the equipment casing and inlet box shaft seals and
shall be of heavy duty, self aligning, anti-friction, sump oil / grease lubricated type with
Vol. – IIC, Section 02.00 ACVS Page 54 of 88
© 2020 MECON Limited. All rights reserved.
TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
Guards
For all external rotating parts like coupling, belts, pulley etc., guards fabricated out of
sheet metal shall be provided.
Base Frame
Fabricated steel bracket of M.S. angles, channels and chequered plates shall be provided
to take static and dynamic load of the fan and motor assembly. The base frame shall be
fabricated of mild steel and shall support equipment housing, bearing pedestals,
coupling guards and drive motor where ever practical. All support mounting faces are
to be machined after all welding is completed. Jacking screws are to be provided
wherever necessary, to allow both lateral and longitudinal movement of equipment.
Vibration Standard
The fans and duct work shall be designed for minimum vibration. Maximum allowable
vibration level shall be as per VDI – 2056 guide lines. Sufficient number of suitable
vibration isolators of approved make shall be provided to ensure isolation of vibration
from the equipment to foundation as per requirement.
Vibration sensors and temperature sensors (RTD) shall be provided for each fan and
temperature sensors (RTD) shall be provided for each motor of centrifugal fan.
Tube axial flow fans shall be of heavy duty wall mounted type as per service
requirement. Axial fan design shall confirm to IS 3588: 1987(RA 1999).
The wall mounted supply / exhaust air fan shall be capable of withstanding the stresses
which may be experienced during normal operation under the condition which it is
required for and during over speed test. The noise level shall not exceed 85dB(A) at 1m
distance.
The first critical speed of the rotating assembly shall be at least 25% above the
operating speed. The speed of the fan shall preferably be limited to 1500RPM for fan
with diameter 600mm or less and 960RPM for fans with diameter more than 600mm to
limit the noise generation.
Vol. – IIC, Section 02.00 ACVS Page 55 of 88
© 2020 MECON Limited. All rights reserved.
TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
Impeller:
The impeller shall be of cast aluminium alloy construction of high efficiency aerofoil
section blades. The fan impellers shall be cast in one piece, finished all over and
carefully balanced both statically and dynamically as per ISO - 1940. Finally the
assembled rotor shall be dynamically balanced.
Casing:
Axial flow fan casings and their components shall be suitable for outdoor installation.
The casing shall be minimum 2 mm thick. The casings shall be provided with flanges at
inlet and outlet. All nuts & bolts associated with it shall be of zinc or cadmium plated.
Easily removable inspection cover having galvanised fly nut shall be provided. The
covers shall be located such that the grease nipple for all bearings and also motor
terminals are easily accessible through the cover.
Exhaust / Supply air fans shall be provided with hood for protection against rain and
other contingencies. It must ensure no dripping of rain water under any circumstances
and will have low pressure drop of air. The hoods shall be provided with a heavy gauge
(14G) expanded metal bird screen.
Rain protection cowls shall be designed for protecting fans from rain. The cowls shall
be provided with bird screen of heavy gauge expanded metal netting. The rain
protection hood & cowl shall be fabricated from minimum 14G thick MS sheet (Hot dip
galvanised).
Fan Drive
All direct drive axial flow fan impellers shall be directly mounted on extended motor
shafts.
Materials of Construction :
Erection
The Bidder shall provide necessary supervisory personnel, all tools and tackles, testing
equipment and instruments, approach facilities, etc. required for complete checking of
installation, testing and commissioning of all equipment with auxiliaries and
accessories. After erection of equipment and all necessary allied work mentioned in
scope of work, ACVS and DE systems shall be tested and commissioned.
The equipment shall be tested and commissioned in accordance with the latest relevant
standards and codes of practice published by Bureau of Indian Standards, wherever
available. In case Indian standards are not available and requirements/ procedures not
mentioned, these shall be carried out in accordance with the latest standards and codes
of practice published by any other recognised National Standard Institution.
The testing and commissioning of other equipment/ components shall be carried out by
respective equipment supplier/ manufacturer to avoid any unforeseen failure of the parts
/ system.
The testing of all sub-systems as well as the equipment as a whole shall be carried out to
ensure that the equipment and its components are in satisfactory condition and will
successfully perform its functional operation.
All tests shall be carried out by the successful bidder using his own instruments, testing
equipment (with valid calibration certificate) as well as qualified testing personnel.
After commissioning, 72 hrs continuous trial run shall be made before handing over the
plant to the Purchaser. Moreover, the guarantee clause and conditions stipulated under
the TS shall hold good even after taking over by the Purchaser. The required operators
and persons for watch & ward, testing & commissioning and for period between final
acceptance test and handing over the systems to Purchaser, shall be provided by the
successful bidder as per site requirement.
The equipment will be subjected to final performance tests and the Bidder shall
guarantee the performance of the equipment upto relevant standards and specifications
to meet the requirements as given in this specification in the presence of the Purchaser
or his representatives. Demonstration of PG parameters will be done by Bidder in an
integrated manner when main technological plants are in full operation. The tests /
checks to be demonstrated by successful bidder will be generally as under:
1. Performance of Air conditioning, Ventilation and De-dusting systems along with all
safety interlocks shall be demonstrated by the successful bidder in the presence of
Purchaser /Consultant.
2. During operations of the equipment at no load and at full load, performance of all the
drives will be checked in respect of current drawn by the motors etc. temperature rise,
vibrations, gear box noise and its heating, bearing heating etc. Consumption of power
and lubricants etc. will also be measured and compared with the respective rated values.
3. Indoor climate condition (temperature, relative humidity) of served premises shall be
measured for consecutive three days, twenty four hours duty condition at two hourly
intervals.
4. Any other observations / tests felt necessary for judging the performance of the system
after mutual agreement between successful bidder & Purchaser will be carried out.
The PG test will be conducted for three (3) consecutive days in the Summer season as
per the date mutually decided by employer/consultant/successful tenderer. However, the
Tenderer, Purchaser/ Purchaser’s representatives will jointly prepare the procedures to
be followed during PG test indicating the period.
Once the installation of ACVS & De-dusting systems are over, there will be a joint
survey with successful Tenderer and Client for total system during daytime. During this
survey, following points will be checked to the satisfaction of Client when the ACVS &
De-dusting systems are under full load operation:
1. Inside condition of air conditioned premises shall be maintained at temp. 23+2 deg C &
55+5% RH.
2. For ventilation system, fan capacity and performance of motors shall be tested at site.
Negative tolerance on unit capacity will not be allowed.
3. Pressure drop across bag filter shall not exceed 140 mm WC.
4. For each system, 3 sets of work area environment readings and emission data at the bag
filter outlet will be collected and the average of 3 readings will be considered as actual
performance of the system and it should be restricted to 70 mg/Nm3. Any abnormality
will be sorted out by mutual discussion at site.
Final Acceptance
All the equipment, plants and system under this TS will be taken over by the Client in
running condition and final acceptance certificate will be issued by the Client when :
a) Performance guarantee tests in respect of sub-units as well as the unit/ system as a
whole have been carried out and integrated performance guarantee values have been
achieved under normal & peak operation of process equipment.
b) All other supplies and services have been completed.
c) Supply of spares has been completed.
d) The successful Tenderer has met any and all other obligations including objections /
observations mentioned in the commissioning certificate.
e) The successful Tenderer has submitted all final documents incorporating latest
modifications in the As-Built Drawings.
f) The unit has operated satisfactorily for a period of 12 months / as decided by client from
the date of commissioning certificate.
g) Warranty period has expired.
02.30 Documentation
The following minimum documents shall be provided by successful Tenderer after the
award of contract as per agreed schedule:
All the drawings shall be made in AUTOCAD and soft copies of all the drawings /
documents shall also be submitted in AUTOCAD (editable version).
Mandatory spares, commissioning spares, special tools & tackles as required shall be
supplied by the Tenderer without any commercial implication till successful
commissioning of VAM, ACVS and De-dusting systems. Unused spares, if any shall be
handed over to the Client.
Recommended two years’ spares list for operation & maintenance of the ACVS & de-
dusting system shall be furnished as per the table given below:
02.32 Painting
The complete paint system for any item shall include the following basic activities:
i ) Proper surface preparation
i i ) Application of primer coats
i i i ) Application of intermediate coats
iv) Application of finished coats
Surface preparation - All surfaces shall be cleaned of loose substances and foreign
materials, such as dirt, rust, scale, oil, grease, welding flux, etc. in order that the prime
coat is rigidly anchored to the virgin metal surface. The surface preparation shall
confirm to pictorial representation of surface quality grade of Swedish Standards
Institution SIS – 055900 or equivalent standards such as SSPC – VIS – 1.67 or DIN
55928(Part 4) or BS 4232 or IS 1477 – 1971 (Par t I).
All fabricated steel structure, fabricated steel pipes, etc. shall have a minimum of two
coats of primer paint before dispatch to site. Total DFT shall be 170 – 200.
Vol. – IIC, Section 02.00 ACVS Page 61 of 88
© 2020 MECON Limited. All rights reserved.
TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
1. The Tenderer shall study this specification carefully and make themselves conversant
with the scheme and the site conditions for the execution of ACVS & Dust Extraction
systems.
2. The Tenderer shall submit the necessary credentials to satisfy the Consultant / Client that
they possess necessary technical know-how of the system and facilities to execute the
order.
3. All items of equipment in this specification shall be complete in all respect including
civil, structural, mechanical, electrical & instrumentation equipment / part as specified
including fasteners, foundation / anchor bolts and nuts, gaskets, base frames, stiffeners,
supports, canopy over the exposed motors, etc. Any item not covered in this specification
but essential for superior design, smooth & safe operation and to meet guaranteed
performance of the system shall be included by the Tenderer.
4. The equipment shall be designed, manufactured and tested in accordance with the
relevant standards prescribed by the Indian Standard Institution (Bureau of Indian
Standard) wherever possible. In cases where suitable Indian Standards are not available,
the equipment shall conform to generally accepted standards and codes acceptable to the
Consultant / Client.
5. All equipment supplied and work done shall be suitable for use under heavy duty
condition of MTPS plant. In the interest of standardization, Client reserves the right of
selecting a particular manufacturer of equipment/ component as indicated in this
specification.
6. The Tenderer shall not off-load the contract or part thereof to any sub-tenderer without
written permission of the Client. In the event of subletting the contract or any part thereof
is permitted by the Client, the fact that such permission has been accorded shall not
establish any contractual relationship between the approved sub-tenderer and the Client
and nor shall release/ free the Tenderer from the obligations under the contract. Facilities
shall be provided by the Tenderer to enable the Client's authorized inspector to inspect the
equipment and their auxiliaries at all stages of manufacture to satisfy themselves as to the
use of proper material and workmanship. Apart from this, the equipment shall be tested or
suitable test facility shall be provided by the Tenderer to enable checking of operational
parameters, if so desired.
7. The work shall be carried out strictly as per the specification and approved drawings and
as per the direction of Client. The Tenderer should quote for the complete job on turnkey
basis in line with the technical specification.
8. All moving parts of equipment which can conceivably cause injury to the operator or
otherwise authorized personnel within the vicinity of the working area, shall be suitably
guarded.
The tenderer shall strictly adhere to the safety norms during the site execution without
fail.
9. The Tenderer shall provide a complete new and unused set of all tools and tackles,
consumables, instruments and spares required for erection, testing & commissioning.
Vol. – IIC, Section 02.00 ACVS Page 62 of 88
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TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
10. The Tenderer shall furnish all technical data of the equipment along with layout &
schematic drawings of system during the tendering stage. However, these data shall be
finalized during detailed engg.
11. The tenderer shall also mention their utility requirement, if any in the technical offer.
12. The Tenderer shall ensure that each equipment is provided with non- corrodable name
plate engraved in English language with the details like supplier's address, operation and
design parameters, weight, precautions, etc.
13. Technical specifications and capacity of the equipment given are for general guidelines
and indicative only. However, the Tenderer will examine and select the equipment and
include other accessories to suit the duty requirements and other performance guarantee
parameter.
14. The Tenderer shall indicate the final kW and frame size for the motor after considering
15% (min) margin over the BkW for all systems (ACVS & De-dusting system) at the
operating condition. However, the tenderer shall ensure that motor rating will be more
than the derated kW at the temperature prevailing at site.
15. The Tenderer shall ensure that the speed of operation of all the mechanical and electrical
equipment shall be kept low enough to reduce noise, vibrations and wear.
16. All equipment supplied shall also meet/ comply with the statutory requirements of the
Government of India, the Government of Tamil Nadu and the latest version of Indian
Electricity Rules and Environment (Protection) Rules of Central/State Pollution Control
Boards, Factories Act etc.
17. No deviation in preferred makes is acceptable unless it is approved in advance by Client.
If any additional make is sought by the successful tenderer during detailed engineering,
then the delay occurred in getting approval of that particular make, shall be solely
attributable to the successful tenderer.
18. All equipment shall be shop tested according to the relevant standards. The particulars of
the proposed tests shall be submitted to the Consultant / Client who shall be given full
access to all the tests as per approved QAP. The client / consultant shall be informed by
the successful tenderer well in advance for the witness of tests / inspection at
manufacturer’s works.
In case, the client / consultant does not make himself / herself available due to some other
exigency for the witness of tests at manufacturer’s works, the supplier shall approach the
Client with all necessary documents for clearance for dispatch of equipment.
19. At the time of inspection, the Tenderer shall furnish internal routine inspection certificate,
material test certificates, approved drawings and QAP etc. to the inspector. Inspection at
different stages of manufacturing as desired by client may be done to satisfy them
regarding the quality of materials, used workmanship, etc. No equipment and material
shall be dispatched to site without inspection certificate / waiver in writing from the
Client. In the event of waiver, shop test certificate including internal inspection certificate
along with other document as per the approved QAP shall be furnished. Inspection shall
be regarded as a check only and shall in no way relieve the successful Tenderer of his/her
responsibility.
Generally, equipment from indigenous sources will be preferred. Imported equipment
shall be included only when absolutely necessary and shall be listed separately with their
Vol. – IIC, Section 02.00 ACVS Page 63 of 88
© 2020 MECON Limited. All rights reserved.
TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
prices. In case of import, the Tenderer shall have to make his own arrangement to
procure and F.O.R supply. The supply of such material with 30% spare parts shall be
ensured only after ensuring availability of after-sales service of the equipment in India.
20. The quantity of items given in Schedule of Equipment and elsewhere in the technical
specification is indicative only. No additional payment is admissible for variation in
quantity of items after award of contract.
21. Language of drawings, name plates of the equipment and operation and maintenance
instructions shall be in English language. S. I. units shall be used.
22. Proper platforms, walkways, railings, toe guards, approach and access to manholes,
dampers, valves, instrument measuring points, etc shall be provided by the successful
tenderer.
23. The successful Tenderer shall make provision for all miscellaneous items required for the
proper operation of the system during demonstrations of all guarantees till final
acceptance test. These shall be made available at site along with the major equipment in
adequate quantities by the successful Tenderer.
24. All materials / equipment shall be properly packed to avoid rusting, pest attack and any
damage during transportation / site storage. However, all damages if any occurred during
transit / storage at site, the responsibility shall rest with the Tenderer only and
rectification of defects (to the satisfaction of client) / replacement shall be done by the
Tenderer without any extra cost to the client. The packing list and dispatch document
shall be included along with the packing.
25. After award of contract, no claim for extra payment submitted by the successful Tenderer
on ground of any special local working conditions or nature of subsoil for foundation
shall be considered.
26. All welding shall be of structural steel standard and only certified welders shall be
employed.
The tenderer shall ensure that 10% safety factor over the design of DES shall be
considered.
Equipment makes shall be as per the list of preferred makes mentioned herein.
27. Initial fill of lubricants, oils, grease and other consumables as may be required for smooth
operation of equipment and systems shall be provided by the successful Tenderer. Any
refill or replacement required upto the handing over of the system shall be provided free
of cost by the successful Tenderer.
28. Noise level generated by the equipment shall not exceed the permissible limit of 85 dB
(A) at 1m distance from the equipment during full load condition.
29. Calibration of all instruments, dimensions in drawings, technical data, weights and
quantities shall be in S.I units. All drawings, name plates of the machinery & equipment
and operation & maintenance instructions shall be in English language.
30. The expected life of plant and equipment shall be taken as 20 years on round the clock
operation basis. All plants and equipment shall be designed with this consideration in
view. Choice of materials, their sizing, surface treatments, etc. shall be decided
accordingly. As far as possible, environment friendly materials and consumables shall be
used.
Vol. – IIC, Section 02.00 ACVS Page 64 of 88
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31. The Tenderer shall guarantee the satisfactory performance of the equipment/systems
supplied by them throughout the year. The Tenderer shall arrange for attending faults,
replacement of components etc. during commissioning of the system and till handing over
of plant to the Client. The Tenderer shall supervise the demonstration of the functioning
of electrical interlocks and control prior to offering the systems for FAT (final acceptance
test). The following reputed/ accepted publications, norms/ guidelines, standards, acts &
rules etc. shall be followed for execution of the work:-
a) B.I.S Publications
b) ASHRAE handbook
c) ACGIH publication, USA
d) ARI publication
e) I.S.O Publications
f) VDI stipulation for vibration level
g) Occupational safety and health act (USA)
32. In the cases where norms/ standards/ guidelines other than those listed above are
followed, the Tenderer shall furnish a copy of such document (s) in support for the
Client's perusal and acceptance. Wherever a contradiction is found between different
documents being followed, the decision of the Client will be final and binding.
The tentative equipment/ components of the systems considered are furnished below.
However, the tenderer shall provide the system in line with the TS :
N. B. : The above list is only tentative and for the guidelines purpose. Any other area
that needs Air conditioning or ventilation and not covered above will also be provided
with the necessary facilities of ACVS without any price implication.
1. VAM - General
a) Application
b) No. of units (working + standby)
c) AC plant capacity (TR)
d) Refrigerant & Absorbent
e) Type of VAM machine ( single effect/double effect)
f) Charge (Refrigerant & Absorbent) of all circuits (kg)
g) Overall size
h) Shipping & Operating weight
a) Make/Type
b) Model No.
c) Maximum power required (kW)
d) Type of capacity regulation
e) No. of steps of control
f) Type of drive
g) Range of load operation
h) No. & type of heat exchangers
i) MOC
• Condenser tube
• Chiller tube
• Shell
• HT generator tube /tube sheet
• LTG tube
• Casing / Impeller for pump
• Bolts /Nuts
• Base frame
j) Auxiliaries
• High /Low pressure gauge (Yes / No)
• High /Low pressure switches (Yes / No)
• Water differential switch (Yes / No)
• RTD (Yes / No)
• Automatic unloading device (Yes / No)
• Solution pump (Yes / No)
• Refrigeration pump (Yes / No)
• Vacuum pump (Yes / No)
• Local control panel (Yes / No)
k) Performance :
• Design hydraulic /pneumatic test pressure (kg/cm2)
• Condenser cooling water side fouling factor
• Water fouling factor for evaporator
• Water fouling factor for absorption
l) Condenser
• Type /arrangement
• Manufacturer /model no.
• Fluid flow rate (m³/hr)
• Inlet/outlet temp (Deg. C)
• Fluid velocity (m/s)
• Pressure drop (allowable / calculated)
• Fouling resistance
• Bundle /Nozzle orientation
• Design (Hydrostatic) test pressure and duration
• No. of passes
• Corrosion allowances
• Connection size (inlet / outlet)
• Thickness (Min/Average)
• Length of tubes
• Thermo wells
• Pressure gauge
• Vent connection with valve
• Drain connection with valve
• Relief valve / fusible plug
• MOC – Shell & Tubes
m) Absorber
• Type arrangement
• Manufacturer / model no.
• Performance / selection chart furnished
• Thermo wells
• Pressure gauge (manometer)
• Vent connection with valve
• Drain connection with valve
• Relief valve
• Anti freeze thermostat
Chiller data
2. Cooling Tower
6. Valves / Strainer
1. Type
2. Make & model
3. Nominal bore in mm
4. Working pressure/Test pressure in kg/cm2
5. Medium handled
6. Type of end connection
7. Material of construction
8. Type of drive (if any)
9. Total weight & quantity
1. Material
2. Make and Class
3. Pipe size, thickness, length, weight & quantity
4. Type & quantity of fittings
5. Hydro -test pressure & duration
a) Ducting
1. m2 of duct work
2. Weight of duct work
3. Weight of support and flanges
4. Material and thickness of duct work & GI glass
5. Duct support type and material
6. Velocity of air for different section of duct
1 Size
2 Quantity offered
Vol. – IIC, Section 02.00 ACVS Page 71 of 88
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METTUR THERMAL POWER STATION - I (4X210MW)
1. Size
2. Quantity offered
3. Material of construction
4. Weight
5. Velocity of air
9. Centrifugal fan
b) Intermediate chamber
1. Size, Material of construction & Thickness of material
c) Adapter section
1. Size, Material of construction & Thickness of material
15. Insulation
17. Motor
18. Instrumentation
20.01 General
Steam shall be supplied at the takeover point (TOP) by the Purchaser. The Bidder shall
make further connections from TOP.
Bidder shall make further connections for steam systems from the TOP complete with
isolation valve, metering devices, controls and instruments.
The scope of work of the Bidder under this specification covers design, engineering,
manufacture / procurement, assembly, inspection, testing, shop painting, supply,
transportation, delivery, storage at site, erection, testing, painting & commissioning of
steam service.
The supply shall include pipes, valves, supports, fittings, insulation, paint material etc.
for the completeness of the system.
Bidder shall also follow the instructions for design, engineering, supply, fabrication,
erection, testing, painting & commissioning of the pipeline as furnished elsewhere in
the technical specification.
• The Bidder shall furnish following drawing / document for information / approval.
• Scheme drawing.
• GA and cross section drawing with binding dimension showing pipe dia,
supporting arrangement, location of valves etc..
• Specification of pipeline.
20.03.01 Steam
Steam shall be available at the TOP from the new boiler at a pressure of 12 kg/cm2 &
temperature of 180 - 2000 C. The size of existing steam header at TOP is DN 100.
Steam will be required for steam based VAM system.
All condensate shall be discharged to drains at suitable interval through traps &
strainers.
General guideline for pipe sizing and other details to be followed are listed below:
For pipe sizing:
i) Pipelines shall be sized by limiting the gas velocity in the pipeline as per below
Table 1.
ii) Peak flow rate based on the distribution pattern shall be considered for sizing of
pipes.
vi) Pressure drop calculation shall be carried-out in order to ensure the required pressure
at consumer end.
TABLE: 1
Sl. Fluid Condition Average Velocity, m/sec Remark
Vol. – IIC, Section 02.00 ACVS Page 77 of 88
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METTUR THERMAL POWER STATION - I (4X210MW)
No Up to DN 50 to DN 200mm s
DN 50mm DN 150 mm and above
1 Saturated At Sub- - 10 – 15 15 – 20
Atmospheric Pressure
2 Saturated At 1 To 7 15 – 22 20 – 33 25 – 43
kg/cm² (g)
3 Saturated Above 7 15 – 25 20 – 35 30 – 50
kg/cm² (g)
4 Superheated Upto 20 – 30 25 – 40 30 – 50
7 kg/cm² (g)
5 Superheated Above 20 - 33 28 – 43 35 - 55
7 To 35 kg/cm² (g)
All Pipe work shall be designed to provide sufficient flexibility against thermal
expansion to prevent development of undesirable forces and moments at points of
connection to equipment, at anchorage or at guide points. Whenever self-
compensation can not be achieved by pipe routing, provision for thermal
expansion shall be made by providing expansion loops. This shall be achieved by
providing U-loop in between two fixed support.
Manually operated shut-off gate valves of size upto DN 450 mm for low pressure
lines shall not have gear drive. For high pressure lines, gear operator shall be
provided as per manufacturer’s recommendations for limiting the operating torque
Vol. – IIC, Section 02.00 ACVS Page 78 of 88
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METTUR THERMAL POWER STATION - I (4X210MW)
to acceptable limits.
Gate Valves of size DN 500 and above shall be preferably provided with
pneumatic actuator to work with air / nitrogen at 3.0 Kgf/cm2(g).
Electrically operated gate valves for gas pipelines of smaller diameter are
recommended to be used only if they are incorporated in the automation scheme.
All valves located remotely, requiring frequent operation and / or with automatic
control shall be provided with electric drives, electro- pneumatic drive, solenoids
etc.
Check valves shall be used in piping system where unidirectional flow is required.
For small size pipes below DN 50, lift check valves shall be used. For DN 50 and
above, swing check valves or dual plate check valve shall be used. Lift check
valves shall be used only in horizontal pipeline. It should not be used in vertical
pipeline.
The Pressure Regulating valve shall be of globe / needle type, with material
specifications, dimensional standards etc. as per Piping Material Specification (PMS)
for the service for which the valve is intended.
For Steam service, sizes up to DN 50, pressure reducing valves of single seated
diaphragm type having in-built strainer, with screwed ends up to DN 20 for PN 10
and below and flanged ends for higher sizes and for higher PN. Body of main and
pilot valves shall be of carbon steel / alloy steel castings / forging, diaphragms
shall be of stainless steel, internal springs of stainless steel and pressure adjustment
springs of spring steel.
For higher sizes to meet larger flow rates, the pressure reducing valves shall be as
per manufactures standards, but capable of meeting the service conditions and duty
specified.
Welded joints shall conform to “Code for pressure piping ANSI B31 1.0 (power
piping) or approved equivalent, except where the welding of such joints is covered by
other code requirements such as IBR, ASME pressure vessel and boiler code or
approved equivalent.
Branches shall, in general, be formed by welding standard fittings. Pipe bends and tees
shall be truly cylindrical and of uniform sections. Where permitted for certain
services, elbows or branch connections may be formed from steel pipe. Unless
otherwise agreed, slip-on welding flanges shall be used on pipe and for
connection to low pressure equipment. Weld neck flanges shall be used for butt
welding fittings as elbows, tees and reducers and for connection to high pressure
equipment. Where class 125 ANSI flanges are bolted to 150 ANSI steel fittings, the
1.5mm raised face on the steel flange shall be removed. When bolting such flanges, a
full face gasket shall be used. Equipment terminal flanges, if consist of a different
standard, a suitable companion flange shall have to be provided at the connecting
points.
Flange drilling shall straddle the natural centre line of pipe. Faces of all flanges
shall be 900 to the longitudinal axis of the pipe to which they are attached. Slip-on
flange when used, shall be welded in accordance with ANSI B31.1 or any other
equivalent code. If distorted after welding, the flange shall be refaced. In all cases,
flange faces, must be free from particles of weld metal. The flange face and the pipe
projecting end shall then be machined to permit both pipe and flange to bear against.
All welding by the electric arc and gas welding process for pipe joints and
fabrication shall be done by qualified welders and done according to appropriate
IBR, ANSI code / regulations as applicable for welding, subject to accompanying
code regulations and standards for filler metal, pressure, temperature and fluid
carried. The ends of pipe and welding fittings shall be beveled according to the
details shown in ANSI B31.1 or equivalent. All welds shall be made in such a
manner that complete fusion and penetration are obtained without an excessive
amount of filler metal beyond the root area. The reinforcement shall be applied in such
a manner that it will have a smooth contour merging gradually with the surface
of adjacent pipe and welded fittings.
Insulated surface of all equipment, piping, valves and fittings shall be covered with
Vol. – IIC, Section 02.00 ACVS Page 80 of 88
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METTUR THERMAL POWER STATION - I (4X210MW)
aluminium sheet of 22 SWG (0.8 mm thick) held in place by self tapping screws of
nickel plated type. Apart from the screw, joints shall be further sealed with a
suitable sealing compound. All fastening materials such as clips, wires for field
weld to the equipment, galvanized wire mesh, metal corner bead shall be
provided. Where valves, pipes fittings, flanges, etc. occur, a clear space between end of
covering and flange shall be left of sufficient length, to permit withdrawal of flange
bolts without interference. Ends of the covering at those joints shall be leveled
from the outside covering to the pipe and sealed.
Flanges, valves bonnet, end flanges and fittings shall be effectively insulated.
Valve & flange insulation covers shall be made in two halves so that these may be
removed/ refitted readily without interfering with the adjacent covering. Protrusions
through the insulation which themselves do not require insulation such as pipe
clamps, supports, small piping, instrument take-offs, etc. shall be covered to the
same thickness as the adjacent insulation and be tightly sealed except at hanger rods.
Ample provision shall be made to prevent damage of insulation due to thermal
movement of the pipe or equipment. All the services to be insulated shall be cleaned
of all foreign materials such as scale, rust and paint by use of steel wire brushes and
steel scrapers. Anti corrosion painting (primer coat) shall be applied on hot surfaces
before application of insulation
Note:
The metallic jacket over the insulation shall be galvanized steel sheet conforming to
IS: 277 with following thicknesses:
Steam line shall be designed to meet the requirement of IBR and necessary approval for
the same needs to be obtained by the Bidder.
i) General
Before erection, the equipment, valves and other fittings to be mounted on
pipelines/ equipment should be dismantled, (only if required), cleaned, oiled and
reassembled. Glands shall be packed with suitable materials as per approved
drawings.
• All elements of the pipelines system shall be erected at site strictly as per the
drawings approved by the / Consultant.
• Any modification to be carried out at site, shall have the prior approval of
/ Consultant’s representatives.
• While erecting, pipelines shall rest uniformly on each support. Yokes,
if provided, shall not allow lateral movement of pipes.
• Matching faces of flanges shall be perpendicular to the axis of pipelines. Use of
gaskets of unusual thickness to fill gap between flanges shall not be allowed.
• For horizontal pipes, the flanges shall be erected such that top two bolt holes
are displaced by half pitch from the vertical axis of the flange.
• Flanges of adjoining pipes shall be located in staggered manner.
• Flanged joints shall be laid as close to the support as possible.
• Bends for steam pipes shall have a radius of not less than three
times the nominal pipe dia unless otherwise specified.
• In general pipes are to be joined by butt welding. However, steam service
pipelines 40 mm & lower sizes shall be joined by socket welding.
• For insulated pipe, steel protectors for the insulation shall be provided at
points where the pipe is supported on rollers, slides or other equipment
where contact with such members is required outside the insulation.
• In case the location of spindle wheel of valves is not clearly shown in the
erection drawings, the same shall be located in a manner as to facilitate easy
operation from ground level of nearest operating platform.
• After erection of pipelines, the holes made in the walls shall be covered with
Vol. – IIC, Section 02.00 ACVS Page 85 of 88
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bricks & mortar. A gap of 10 to 20 mm shall be kept between wall and the
pipe for the movement due to thermal expansion. The gap shall be filled with
felt/ asbestos.
• Holes made in the roof shall be covered with removable CGI sheets.
• The trenches for pipes shall be covered with removable chequered plate
covers/ concrete slabs as per the drawings.
• All pipeline branches not connected to equipment shall be closed using blank
flanges and gaskets.
• Leakage test shall also be carried-out at 1.1 times the maximum operating
pressure to check the leakage by soap solution. Test duration shall be minimum 2
hours.
• Soap solution shall be applied to the weld surfaces / flanges to check for any
leakage.
• Any defect found shall be rectified after releasing the test pressure and after
rectification of defects the test shall be repeated.
• The maximum allowable pressure drop in all gas pipelines shall not exceed 1.0
% per hour for outdoor pipelines during pneumatic test. For pipeline subjected to
hydro test, no leakage is permissible
When steam is observed from all drain points and consumer ends then steam
valve at the inlet to the system should be fully opened and all by pass valve
on drains closed and isolation valve on steam traps are kept open.
A Pressure Reducing Station shall be under the scope of Tenderer. This shall
include Pressure reducing valve with an isolation valve uptseam & downstream
PRV and a by pass throttle valve with an isolation valve uptseam & downstream
throttle valve. Futher, pressure measuring devise upstream & downstream shall
also be provided.
weight for counter weight buffers. The oil buffers shall be self-resetting type. They will
also be provided with means for determining the oil level.
03.01.10 Guide Rails
Steel elevator guide rails shall be installed to guide the car and counterweight, erected
plumb and securely fastened to the building structure, filled and filled to ensure smooth
joints.
03.01.11 Roller Guides Shoes
Rubber encased coil spring tension adjusted roller guides shall be provided for
passenger elevators with speed of 1.00 m/sec or greater, mounted on top and bottom of
the car frame, and on top and bottom of the counterweight frame to engage their
respective guide rails.
03.01.12 Hoistway Operating Devices
Redundant series wired terminal stopping devices shall be provided to slow down and
stop the car automatically at the terminal landings. Resetting a tripped devices shall be
done manually only.
03.01.13 Compensating Rope
Compensating ropes shall be provided to compensate for the shifting weight of the hoist
rope. Compensating chain where provided shall be noiseless type polyurethane
enclosed chain.
03.01.14 Counter Weight
A structural steel frame with cast iron or steel plate filler weights shall be furnished to
provide proper counterbalance for smooth and economical operation.
03.01.15 Counterweight Guard
A metal (a suitable guided structural steel frame with suitable weights) counterweight
guard shall be provided and installed at the bottom of the hoist way, and shall wrap
around counterweight rails for a height of no less than 1.80 m in order to protect
accidental contact.
03.01.16 Belts/Wire Rope
Flat coated steel belts/Wire Rope of adequate size, construction to insure proper
operation of the elevator and give satisfactory and safety assurance. Belts/ropes shall
conform to governing codes or regulations. The factor of safety for belt system shall be
minimum 12.
The Lift shall be provided with inbuilt system to monitor the integrity of the belt
cords/Wire Rope for ensuring the safety.
03.01.17 Hoistway Materials
Vol. – IIC, Section 03.00 ELEVATOR, CRANE & HOIST Page 3 of 19
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METTUR THERMAL POWER STATION - I (4X210MW)
All hoist way materials shall be non-flammable except travel cable cladding which shall
be flame resistant. All other electrical cables / wires shall be FRLS and housed in metal
conduit or other metal enclosures. Isolation pads shall be provided in hoist way Cable
shall conform to codes and shall anchor to the frame by means of an equalizing device
to insure uniform cable loading. Cable safety shall minimally conform to governing
code. Travelling cable shall be secured to the cars underside. Cable shall be clear of all
obstructions while car is in motion. Cable jacket shall be rated for immersion in water,
salt water and oil. Jacket restraint shall minimize strain on conductor.
03.01.18 Hoistway Entrances
For each landing served, a complete elevator hoist way entrance with stainless steel
baked enamel painted steel hoist way door frame shall be installed. Each entrance shall
have centre opening two speed horizontal sliding type doors suitable for a clear opening
as per above data sheet, and shall include flush doors of hollow metal pan type
construction, extruded aluminium sill with anti-slip grooving on the surface door,
hanger supports and hanger cover. Exposed surfaces of doors and frames shall be
finished as per building’s Interior Design. Corrosion resistant coating shall be applied,
wherever required, prior to completion of the installation.
03.01.19 Hoistway Doors
Sheave type two point suspension ball bearing door hangers and tracks complete shall
be provided for each hoist way opening and adjustable ball bearing rollers shall take the
up thrust of the doors.
Each car and hoist way door leaf shall be fitted with two Teflon or nylon Gibbs as
bottom door stabilizers.
03.01.20 Architraves and Doors
Doors, threshold, door hangers and electro mechanical locks shall be as a system, fire
rated for not less than 1 hour.
03.01.21 Car and Hoistway Door Operator
For each elevator door, a Variable Voltage Variable Frequency (with harmonic filter)
door operator shall be furnished to simultaneously open the car and hoist way doors
when the car is at a landing. The doors shall be closed simultaneously by motor power.
Emergency key provision shall be made to open doors at all landings from outside of
the hoist way. The door speeds shall be controlled independent of hydraulic cushioning.
In the event of interruption of electric power or failure of which shall prevent elevator
movement away from the landing unless the door is in the closed position. Each hoist
way door shall be equipped with a positive electromechanical interlock and auxiliary
door closing device so that the elevator can be operated only after the interlock circuit is
established.
Vol. – IIC, Section 03.00 ELEVATOR, CRANE & HOIST Page 4 of 19
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The doors shall open automatically while the car is levelling at the respective landing.
The doors shall automatically close after a predetermined time interval has elapsed, but
the momentary pressure of the "door open" button provided in the car shall reverse the
motion and reopen the doors and reset the time interval unless over ridden by the infra -
red beams monitoring the open door.
The operation shall be possible with or without attendant with the provision of key in
the main operating panel. The emergency push button shall also be provided to
facilitate stopping of elevator at particular landing cancelling all the registered calls.
It shall not be possible for the car to be started or kept in motion until all the landing
doors and the car door are locked in the closed position.
It shall not be possible to open the landing door from the landing unless the elevator car
is within the particular landing zone.
03.01.22 Sheaves
Sheaves shall be mentioned, balanced and shall maintain cable / sheaves ratio well
within code requirements. Lubrication points shall be extended to a location that is
easily accessible.
03.01.23 Carframe And Safety
A car frame fabricated from formed or structural steel members shall be provided with
adequate bracing to support the platform and car enclosures. The car safety shall be
integral with car frame, and shall be of the flexible guide clamp type designed to stop
and hold a fully loaded car which exceeds descending speed. It shall withstand without
deformation the operation of safety gear.
The car shall be so mounted on the frame that vibration & noise transmitted to the
passengers inside is minimum.
The MS parts of the frame and the sheets exteriors within the shaft shall be painted with
approved quality Epoxy paints.
03.01.24 Platform
The car platform shall be checkered plate steel construction. It shall be equipped with
slip resistant threshold. The entire platform shall rest on rubber pads, so designed to
form an isolating cushion between the car and car frame. Platform deflection shall be
limited to maximum 3 mm under maximum normal operating conditions. Platform shall
conform to local codes. Approved coloured granite floor finish shall be provided. The
weight of the granite stone shall be considered as the part of dead weight of the car.
03.01.25 Infra - Red Beam Detector
An infra - red beam device with emitters & receivers shall be installed on passenger
elevator. This device shall monitor traffic across the threshold of the door and shall
Vol. – IIC, Section 03.00 ELEVATOR, CRANE & HOIST Page 5 of 19
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initiate door closing 2 seconds after last beam interruption, thus overriding door open
period. There should be minimum of 50 beams criss - crossing across door height.
There shall be no zone in the entire opening that is not monitored by the device.
03.01.26 Over - Load Feature
All elevators shall be fitted with over load warning indicator based on sensing relays
fitted in the platform of elevator cabin to illuminate and sound a buzzer to indicate "
Over - load " and subsequently defeat the car's operating circuits when car load reaches
110% or more of rated load. Car platform may require stiffening to minimize margin of
error resulting from excessive deflection.
When the load exceeds 80 % of the rated load, the car will bypass automatically all the
hall calls along the service direction. This feature shall be effective under full automatic
mode i.e. without attendant service.
The elevators described in these standards must be equipped with an automatic rescue
device which will upon power failure, automatically move the elevator to the nearest
landing, opening of landing doors and facilitate the rescue of the passenger in the
elevator and parks with door open at that floor.
ARD shall activate rescue within 10 sec of power failure.
All the lift safeties should remain active during the ARD mode of operation.
The elevator shall be automatically switched over to normal operation as soon as
normal power supply returns.
Battery (Type Ni-Cd, maintenance free ) capacity shall be adequate so as to operate the
ARD at least seven times a day, provided the duration between usage is at least 30
mins.
The elevators described in these standards must be equipped with fireman switch ( at
Ground Floor) which will upon manually operated key switch automatically move the
elevator to the ground floor/lobby. All floor and car buttons shall be rendered
ineffective until the system is manually reset. A key operated switch provided at the
ground floor to activate and reset the retrieval system manually. Self-testing facility
shall be provided for the entire Elevator after restoring mains power.
On initiation from the fire alarm system, all elevators travelling away from the lobby
floors shall stop and reverse with opening their doors indicating fire mode operation to
passengers, ignore all car and hall calls and express to the lobby or alternate landing
floor.
Cars travelling toward lobby shall express to lobby ignoring all car and hall calls. Cars
parked at intermediate floor shall close their doors and express to lobby. Cars parked at
lobby shall open their doors ignoring car and hall calls. At hall and car buttons shall
extinguish and shall accept no further hall or car registration.
Limit switches shall be provided to slow down & stop the car automatically at the
terminal landings & ultimate limit switches shall be provided to automatically cut off
the power & apply the brake, should the car travel beyond the terminal landing.
Shall be linear and smooth. Stops shall be made without cable oscillations.
03.01.31 Noise Levels
Noise from all stationary equipment shall not intrude into adjoining public areas. Noise
from moving equipment including door operation, car motion, fan, wind, etc. shall not
intrude into adjoining corridors.
03.01.32 WIRING:
Al wiring and electrical interconnections shall comply with governing codes and
manufacturer standards. Insulated wiring shall have flame retardant and moisture proof
outer Covering, and shall be run in metal conduit, tubing or approved electrical
raceways. Travelling cables shall be flexible and suspended to relieve strain on
Vol. – IIC, Section 03.00 ELEVATOR, CRANE & HOIST Page 7 of 19
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METTUR THERMAL POWER STATION - I (4X210MW)
A scrolling alpha numeric car position indicator shall be installed above each operating
panel. The position of the car in the hoist way shall be shown by illuminating the
corresponding landing at which the car is stopped or passing.
Recessed surface mounted directional lanterns with stainless steel faceplates or finish
specified by architects shall be provided at all hoist way entrances, with up and down
indications at intermediate landings and single indication at terminal landings. When a
car is stopping at a landing, the lantern shall indicate the direction in which the car is
travelling and shall become illuminated prior to arrival of the car.
A full length car operating panel shall be provided in each passenger car. The car
operating panel shall contain a bank of Led illuminated push buttons of micro pressure
type (with Braille markings) with a maximum movement of 1.5 mm marked to
correspond to the landings serviced. It shall include a series of push buttons
corresponding to the floors served, along with an emergency stop and switches
required. Operating panel shall incorporate the following: floor buttons, door open /
close, emergency stop / alarm, up / down in manual mode, man / auto key switch and
fire operation.
A locked compartment integral with operating panel shall contain
a. Up / down button.
b. Open / shut button
c. Alarm Button
d. Floor Button
e. Emergency stop button
f. Car direction indicator
g. Car position indicator
h. Fireman’s service indicator
Vol. – IIC, Section 03.00 ELEVATOR, CRANE & HOIST Page 8 of 19
© 2020 MECON Limited. All rights reserved.
TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
i. Overload indication
j. Telephone
k. Key for with or without attendant operation.
l. Fire extinguisher as per IS codes shall be provided in the car.
A separate lockless cabinet shall house the emergency telephone.
The cabinet manufacturer shall make all provisions for installation of lighting fixtures
including integration of emergency lighting fixtures. Car light shall be equipped with
Automatic sleep provision.
Cross flow fan with automatic sleep provision (size of fan minimum 300 mm dia) shall
be provided in the car.
03.01.37 Fixture Finishes:
The metal faceplates and required accessories for the operating as well as signal
devices in the cars and at the landings, shall be stainless steel as specified in data sheet.
k. The contractor shall guarantee the smooth and noiseless performance of the elevators
System.
l. Any other test felt necessary by Purchaser and supplier to ensure proper functioning
and installation of the lift.
Test load & other equipment (stop watch etc.) shall be arranged by the contractor.
2.0 Vendor shall keep all his testing instruments duly calibrated against standard meters not
earlier than 6 months from the date of test of the equipment covered under this
specification, in the presence of Purchaser. Calibration certificates shall be made
available during inspection.
03.01.43 DOCUMENTATION
The tenderer shall submit adequate sets of following technical drawings & technical
data/ information with tender
a) General arrangement drawing of elevator showing full details in plan and sections.
b) GA, BOM & Data sheets for various electrical components like motor, Panels etc
c) Single Line Diagrams / Circuit diagrams
d) Quality Assurance Plan for inspection.
e) Test and inspection certificate.
f) List of spares for 2 years normal maintenance.
g) List of insurance spare for each elevator
h) List of special/ maintenance tools & tackles.
03.01.44 QUESTIONNAIRE
25. Signals :
27 Special Feature :
03.02.01 General
b) For outdoor hoists, motors, brakes & other equipment shall be covered to suit to
outdoor operations.
d) Power supply shall be through flexible trailing cables, which shall be clamped with
PVC or non-metallic clamps or shrouded Bus bar.
f) Defects in the materials like fractures, cracks, blowholes, or laminations are not
allowed.
g) No cast iron parts shall be used except for electrical equipments and no wood or
combustible material shall be used unless specifically mentioned otherwise.
i) All bolts except those with nyloc nuts shall be provided with grip lock nuts or spring
washer.
j) All parts of the hoist shall be thoroughly cleaned of all loose mill scales, rust or foreign
matter & then painted as specified. All parts inaccessible after assembly shall be
painted before assembly & assembled while paint is still wet.
k) All Electric hoists shall be provided with maintenance / repair platforms with handrails
and ladder at one end wherever layout permits.
l) All parts except motors, resistors, thrustors, solenoids, etc. shall be de-rusted manually
& painted before assembly& assembled while paint is still wet.
m) All the hoists shall be provided with a maintenance platform with ladder approach at
one end of the monorail.
Electrically operated hoist shall be a complete unit with travelling trolley, hoisting
motor, travel motor, rope drum, wire rope, necessary gearing, sheaves, brakes, hook,
pendent push button station, contactor panel, all wiring, conductor for travel motion ,
limit switches, end stops, buffers, earthing terminals and other accessories to make the
equipment complete in all respects.
The travelling trolley shall be motor driven. Trolley frames shall be fabricated from
rolled structural steel sections. The side plates of the trolley shall extend beyond wheel
flanges, thus providing bumper protection for the wheels. The two side plates shall be
connected by means of an equalizing pin.
The electric hoist shall run on two pairs of wheels, a pair of which shall be driven by
motor through reduction gear. The wheels shall be of cast steel/forged steel, single
flanged with taper / parallel treads to suit to monorail. The wheels shall be machined on
their treads to match the profile of the monorail. The wheels shall be mounted on
anti-friction bearings & shall be easily removable for repair & replacement. The wheel
diameter shall be selected such that skidding does not take place even under unloaded
condition.
The hoist mechanism shall consist of a bottom block fitted with a standard forged
swivel hook of the specified capacity, supported on 2 or 4 falls of wire rope. However,
non-spinning type of wire rope shall be used for 2 falls rope arrangement. The wire
rope shall be wound on a grooved drum which shall be sufficiently long to
accommodate in one layer the length of rope requisite for the specified lift & in
addition not fewer than two turns at each anchored end & one spare groove at the
opposite end. The hoist drum shall be motor driven through gears enclosed in oil filled
reduction gearbox.
Rope drum shall be of cast steel or fabricated out of rolled steel plates. Fabricated rope
drum shall be stress relieved before machining. The grooves of the drum shall be
smooth finished.
The wire ropes shall be of regular right hand lay hemp cores as per IS: 2266-2002.
However, Ropes working under water and in corrosive atmosphere shall be galvanized
and shall have steel core. For rope arrangement with 2 falls wire rope, shall be of non
spinning type.
Rope sheaves shall be of cast steel or fabricated out of rolled steel plates.
Suitably designed rope guides with pressure ring/rope tightened shall be provided for
each lead of rope from the rope drum to prevent the rope from overriding, loosening or
rope coming off the groove.
08. Gearing.
Straight & helical spur gearing shall be used for all motions. Worm & bevel gears shall
not be used without specific permission from purchaser. Preferably all first reduction
gears shall have single helical teeth. All gears shall be hardened & tempered alloy or
carbon steel with machine out teeth. Surface hardening of teeth is not acceptable. All
gears shall be enclosed in oil filled gear box except when not possible.
09. Lubrication
All gears & bearings shall be lubricated either by splash lubrication or by grease. If
possible, all the lubricating points shall be grouped together in easily accessible
positions.
10. Bearings
Ball & roller antifriction bearings of reputed make shall only be used, with minimum
bearing life as per IS: 3938.
Shafts and axles shall be of forged steel and shall have ample strength, rigidity and
adequate bearing surface for intended duties. Shafts and axles shall be accurately
machined and properly supported. Shafts shall, as far as possible, be furnished straight.
If shouldered, these shall be provided with fillets of ample radius or shall be tapered to
avoid loss of strength and stress concentration. These shall be designed considering
allowances for keys and splines.
12. Motors/Couplings
For Hoists o f c a p a c i t y 5T & above, the motor (Foot mounted B3 type) shall
be connected to its gear drive by a flexible coupling. Flange mounted motors
(B5) may be used for Hoists of capacity upto 5T and also for all CT drives.
The number of poles of motor for hoist & CT drive shall be Minimum 6 & 4
respectively.
The lifting hook shall be single hook type, solid, forged, heat treated, of rugged
construction and provided with a standard depress type safety latch. Lifting hook shall
have swivels and operate on ball or roller thrust bearings with hardened races. Lock to
prevent hook from swivelling shall be provided. Lifting hook shall conform to IS
15560:2005 as applicable.
14. Brakes
DC Electro-magnetic Shoe brakes shall be provided for Hoist motion of capacity 5 T &
above. DCEM Disc brake may be provided for Hoist motion of capacity below 5 T. CT
Motion shall be provided with DCEM disc brake. Brakes shall be provided on the high
speed pinion shaft of the gear –train.
Spring or rubber buffers shall be provided on the trolley. Suitable end stops shall be
provided which shall be welded on the ends of monorail to contact the buffers mounted
on the trolley.
Trolley wheel stops shall be provided before the end stops. These shall match to wheel
radius. Stops to prevent trolley from running off the monorail shall be abutted against
ends of monorail. Stops shall be welded to the monorail.
Sweeps shall be attached to the trolley to remove foreign material from the rails.
16. Guards
All exposed couplings, shafts, gear wheels, pinions, drives etc. shall be safely encased
and guarded.
The sheaves of hook blocks shall be guarded to prevent trapping of hand between a
sheave and the in-running rope
03.03.03 Documentation
f. Detailed layout plan and sections for power supply system. (Angle Bus
bar/Shrouded BusBar/ Festoon Cable etc.)
g. DSL / Trolley line arrangement layout.
a. Requisite no. of sets of all GA drawings, complete assembly and sub assembly
drawings of the equipment.
b. Drawing of all equipment/ component received from sub supplier.
c. Engineering and design calculations.
d. Test and warranty certificate for each item of equipment.
e. Detailed erection schedule and manuals, assembly/ erection drawings, erection
sequence, special precautions to be followed during assembly/ erection (these
shall be despatched three months prior to FOT/FOR delivery).
f. Test reports and inspection reports.
g. Instruction manuals for testing and commissioning.
h. Operation, maintenance and safety manuals.
i. Requirement of special tools and tackles, if any, for subsequent maintenance.
j. Detail drawing and specifications of all wearing out parts and parts subject to
breakage during normal operating conditions
k. List of spare parts with drawings, sketches, specifications and manufacturer’s
catalogue
l. All other drawings and documents as stipulated in General Conditions of
Contract.
03.03.04 Qusetionnaire
i/ Equipment No.
ii/ Nos. off
iii/ Type
iv/ Capacity (t)
v/ Height of lift (m)
vi/ Duty class
vii/ Location
viii/ Hoists :
a) Speed with safe working load, m/min
b) No. of rope falls supporting the load and specification of rope
c) Lift of hook above floor, m
d) Drop of hook below floor, m
e) Motor details like type, kW, Pole, %CDF, no. of start/Hr, Duty, POT, Insulation
& enclosure class, qty, Make etc.)
f) Make, type and size of brake
ix/ Cross – travel :
a) Speed with working load, m/min
b) Wheel base, mm
c) No. of wheels
Vol. – IIC, Section 03.00 ELEVATOR, CRANE & HOIST Page 18 of 19
© 2020 MECON Limited. All rights reserved.
TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
d) Moor details like type, kW, Pole, %CDF, no. of start/Hr, Duty, POT, Insulation
& enclosure class, qty, Make etc.)
e) Make, type and size of brake
x/ Power supply
xi/ Control voltage
xii/ Made and type of control
xiii/ Total weight of hoist (t)
xiv/ General arrangement drawing showing details as enumerated
xv/ List of deviations from the purchaser's specification in the format enclosed.
04.01 Introduction
In order to combat any occurrence of fire in various areas/units of the proposed FGD
system for existing power plant of Mettur Thermal Power Station-I (4X210MW), an
elaborate system of fire protection will be provided. The system will be planned in
conformity with Tariff Advisory Committee’ guidelines,BIS and other relevant
standard/codes.
The scope of work covers on turnkey basis design & engineering, supply, erection,
painting, testing, commissioning, and handing over of complete Fire Protection System
envisaged for the proposed FGD system for existing power plant. Two years operation and
maintenance spares, necessary tools, spanners etc. required for regular operation /
maintenance of systems will be supplied along with the equipment and will be mentioned
in the offer.
a/ Bidder will be provided firefighting water at a single point as indicated in the drawing;
however bidder has to tap water from this point and further design and supply of the
entire firefighting facilities under their scope of work.
b/ Fire Hydrant system consisting of internal as well as external hydrants for the area
earmarked for FGD system. Number of hydrant and monitor points shall be finalized at
detailed engineering stage as per Norms.
c/ Automatic Clean agent total flooding system for computer rooms/ PLC room/control
rooms.
d/ Microprocessor based Fire detection and Alarm system for electrical premises and
premises with automatic fire extinguishing system.
e/ Detector shall be multi criteria combination of rate of rise heat detectors and photo
electric smoke detector. Ionization smoke detectors are not to be accepted.
i/ All electrics.
m/ Erection, testing, commissioning, PG test and Warranty for the complete fire protection
system.
n/ All the requirements of TAC for complete FPS will be incorporated by the bidder in
their scope irrespective of whether the details are described in specification and/or
shown in the drawings or not.
04.03 The scope of work and services to be rendered by the bidder for installation of fire
protection systems will include but will not be limited to the following activities.
ii/ Miscellaneous materials and services will include but not limited to the following :
a/ All piping integral to and/or between any equipment furnished under this specification,
except as otherwise specified.
c/ Foundation bolts, base plates, thrust blocks, duck-foot bends, matching flanges,
supporting materials and shims.
d/ All necessary instruments, power and control wiring integral to any equipment
furnished under this specification. These will include terminal blocks and integral
wiring to the terminal blocks for equipment requiring external connection.
e/ Earthing strips of all panels, & other firefighting equipments supplied by the bidder will
be connected to the nearest earthing ring available at site.
g/ GI pipes/ conduits and other accessories wherever required for laying of cables.
h/ Other erection materials like cable supporting structures, channels, brackets, clamps
and other hardware materials, as required, for laying of cables.
j/ All necessary connections for hook-up with other system, if required as per instruction
of the purchaser.
l/ Initial fill of gas and other fire extinguishing media (including quantity required for PG
test) and demonstration.
a/ Scope of work with general description of system and equipment offered specifying the
important features supplemented with scheme drawings. The bidder has to give a
confirmation with respect to the scope of work as detailed in this specification
excepting for the deviations, if any, to be listed in the schedule of deviation. The
Vol. – IIC, Section 04.00 FIRE PROTECTION SYSTEM Page 3 of 21
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TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION-I (4X210MW)
c/ Time Schedule (Bar Chart L1) for implementation of jobs and number of persons to be
deputed at site along with their experience/ qualification and period of posting at site.
g/ Certificate of approval from TAC and similar other authorizing body for various
component of the system.
i/ Piping layout drawing with complete support detail, isometric layout for hydrant system,
clean agent gas system.
vi/ Distribution of extinguishers with respect to their type, capacity and numbers in various
premises will be decided in accordance with IS – 2190-2010. A drawing/table showing
such distribution shall be submitted for approval.
a/ Manufacturer's routine test and type test certificates for all equipment and cables.
b/ Detailed technical catalogues/data sheet/brochure for all the equipment.
c/ Instruction manuals for erection, maintenance and operation of all the equipment.
04.05 Refer Vol - IV/ Electrical Section for Fire Detection & Alarm System
04.07.01 General
Clean agent Inert gas “CLEAN Agent Gas (IG-541)” total flooding system shall be
provided for the following areas including above false ceiling and below false floor areas.
The system shall be designed as per NFPA 2001 (Latest Edition).
The scope of work and services to be rendered by the Bidder for installation of clean
Agent total Flooding System shall include but not limited to the following activities:
i. Design, Engineering, manufacture, fabrication, assembly, shop testing and shop painting,
sequential packing, delivery for site, comprehensive insurance, unloading, unpacking,
storage at site, site handling, preparation of erection drawings, fabrication and erection as
per approved drawings, site testing, painting, commissioning and performance guarantee
of Clean Agent Total Flooding System in integration with complete fire protection system
required for below false floor, and above false ceiling for main control room, PLC room as
per NFPA 2001 (Latest Edition).
ii. Supply of mandatory spares required for two years operation and maintenance initial fill
consumables.
The Inert clean gas total flooding system is an engineered system consisting of fixed
nozzle and gas distributing network. The system shall be designed and installed in
accordance with the NFPA 2001 (Latest Edition). Inert gas clean agent system will
extinguish surface burning fire in Class – A, B & C hazards.
i. Gas
ii. Cylinder rack
iii. Gas Manifold
iv. Pressure reducing devices
v. Pilot Cylinder, cylinder valve assembly
vi. Cylinder Bank
vii. Electric Actuator
Vol. – IIC, Section 04.00 FIRE PROTECTION SYSTEM Page 5 of 21
© 2020 MECON Limited. All rights reserved.
TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION-I (4X210MW)
The Inert gas clean agent is stored in metallic cylinder in a pressurized condition at
200/300Bar. A master cylinder will be fitted with Electric Actuator & manual actuator.
Separate multiple cylinder bank dedicated for each risk area is provided close to the
protected area. No. of cylinders in each bank will be determined as per volume of gas
required for total flooding as indicated above. All the cylinders are connected to a
discharge manifold by means of flexible hoses. The manifold is connected to piping
network having discharge nozzles at the protected areas. All the piping is supported &
clamped suitably to avoid vibration.
The system shall consist of "independent engineered storage" system with 100% (one
hundred percent) connected reserve supply cylinders. The main or reserve supply
cylinders shall be designed for the requirement of largest risk with directional valves for
each of the zones. Suitable selector switches shall be provided for "Normal/Standby"
supply selection in the fire alarm system panel for each of the zone. The cylinders shall be
located in a separate room civil building near to unit control room. This room shall be
provided illumination facility, ventilation facility.
All the above areas are air conditioned, provided with false ceilings and false floor
separated from the adjoining areas (both the above and false ceiling spaces) by brick
walls.
Each zone shall be equipped with fire detection system. On receiving the fire signal from
the detection system agent gas shall be released automatically after a set time delay and
gas shall be discharged into the enclosed space.
The system shall comprise of the following mode of operation and actuation and
Vol. – IIC, Section 04.00 FIRE PROTECTION SYSTEM Page 6 of 21
© 2020 MECON Limited. All rights reserved.
TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION-I (4X210MW)
The clean agent shall be discharged / actuated automatically after an adjustable time delay
based on the detection signal received. The delay shall be minimum 30 seconds. In the
local control panel of clean agent system, there shall be one hooter, which shall operate
once the gas is released during time delay; there shall be pre-discharge alarm (audio +
visual). Hooter shall follow the alarm once the gas is discharged.
The release of gas shall be preceded by an audio visual alarm in the affected area for
alerting and evacuating the personal and for this purpose time delay of about 60 seconds
(which is settable from the panel) between the initiation of release and actual release of
gas. The exact time delay to be incorporated in the system shall be decided during detailed
engineering.
To avoid an inadvertent mal operation and release of gas, on either of the model release
operation (auto or manual), provision of manual interruption (i.e.) gas charge inhibition
facility through a suitable device from a local control unit at a suitable location or from the
panel shall be provided so that the agent release can be stopped within the time delay.
Quantity of gas required for the system shall be based on the gas required to blanket the
volume of the area to be protected and time that the discharge must be maintained to
assure complete extinguishing of fire within 10 sec after actuation.
i. Complete design and all the system components/equipment shall be approved and listed
by UL/ VDS/FM.
ii. Design, manufacture and installation of inert gas fire extinguishing system shall be in strict
accordance with NFPA 2001 (latest edition) and certified by UL / VDS/FM.
iii. 200/300 bar clean agent extinguishing system shall be designed and installed for below
false floor, main room and above false ceiling of various risk areas.
iv. The design concentration shall be as per NFPA 2001 if the system is UL/FM approved. If
the system is Vds approved then design concentration shall be as per vds standard only.
v. The Physical properties and its discharge characteristic of clean agent shall meet the
requirements of NFPA-2001 (Latest edition).
vi. The design calculation shall be supported by UL/VDS/FM listed software guidelines and
shall have their approval.
vii. The system shall be designed based on the single largest risk area. In order to optimize the
requirement of gas and considering the space for cylinder bank, it may be planned to club
together requirement of two or more adjacent premises. Bidder to ensure that appropriate
logic is followed for discharge of gas in respective premises.
viii. The system shall have 100 % Clean Agent filled standby cylinders along with manifold,
directional valves and automatic change over for each risk area.
ix. The complete volume of the rooms including the above false ceiling shall be considered
for estimation of quantity of gas and containers.
x. When determining the gas quantity, the leakage losses from the enclosure shall be taken
into account by the supplier. The exact amount of gas to compensate for leakage
compensation shall be designed by the Bidder taking into consideration the type and
features of enclosure, unclosable openings if any and other considerations so that design
concentration is achieved after stabilization of discharge. However, a minimum 20%
margin to be considered as leakage compensation and extinguishing efficiency.
xi. Further volume of re-circulating type air conditioning system & its ductwork (at least up to
the automatic fire dampers of the ducts) shall be considered as a part of the total volume so
that the design concentration is achieved throughout the hazard area. Further gas quantity
shall be adjusted for ambient pressure conditions.
xii. Both the main & reserve supply cylinders shall be permanently connected to the
distribution piping through manifold and arranged for easy changeover from the panel.
xiii. The discharge time period shall be that the design concentration can be achieved within 60
seconds. The flow calculations shall establish these criteria.
xiv. The quality of gas shall conform to relevant design standard ie: NFPA - 2001
xv. Bidder shall include automatic actuation of the system by Fire detection and alarm in the
premises concerned. Annunciation for system operated will be provided in MFAP and
annunciation panel. Bidder shall consider clean agent discharge panel (intelligent type) –
with battery charging facility. All signal & control of gas system shall be controlled from
Vol. – IIC, Section 04.00 FIRE PROTECTION SYSTEM Page 8 of 21
© 2020 MECON Limited. All rights reserved.
TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION-I (4X210MW)
gas discharge panel. Signal shall repeat as main fire alarm panel. Interface unit between
gas discharge panel and MFAP shall be provided by the bidder by considering the
requirement of MFAP. Provision for fire delay and evacuation alarm shall also be given.
xvi. Concentration of gas shall not exceed the NOAL and LOAL level as per NFPA guide
lines.
xvii. All electrics including power supplies and control interlocking, provision of MRPS,
inhibitor, evacuation alarm, hooters, all components required for ventilation tripping etc
shall be considered in the design and supply.
The quantity of clean agent gas provided shall be sufficient to protect the risk area with
100 % standby. Every individual risk shall have its own distributing pipe, nozzles, alarm
and actuation system etc. The physical properties of clean agent gas shall meet the
requirement specified in the NFPA 2001 (Latest Edition).
Both the main and standby cylinders shall be permanently connected to the distribution
piping through manifold and auto change over. The clean agent discharge shall be
substantially completed in a normal 60 seconds. For inert gases the measured discharge
time is considered to be the time when the measuring device starts to record reduction of
oxygen until the design oxygen reduction level is achieved. The min. oxygen
concentration shall be as per NFPA 2001 (Latest Edition).
System flow calculations shall be performed using a calculation method listed or approved
by UL/VDS/LPC/FM. The system designed shall be within the manufacturers listed
limitations. Bidder shall provide the sufficient measure facilities in the risk areas to
dissipate over pressurization due to release of clean agent and also provide calculation in
support of same for each protected area.
The Bidder shall provide the approval certificate of software from UL listed along with
design calculation.
Minimum design concentration of Clean Agent gas shall be as per NFPA-2001 (Latest
Edition) at 700 F by volume for Clean Agent fire extinguishing system based on approved
/ listed flow calculation method and having design concentration approved by UL/FMRC
at 700 F (210 C) for the single largest risk.
Vol. – IIC, Section 04.00 FIRE PROTECTION SYSTEM Page 9 of 21
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TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION-I (4X210MW)
Clean Agent concentration requirement shall be computed considering the volume of the
class C high hazard area as specified. In addition to the concentration requirements as
specified, 20% of the gas quantity as computed above, shall be added to compensate for
leakages and extinguishing efficiency. The Bidder shall work out the quantity of Clean
Agent as per NFPA 2001. However, Bidder shall quote minimum quantity of clean agent
for the volume as given in the Scope of work.
ii. All the storage cylinders (cylinder bank) shall be provided under an enclosure. It shall not
be kept open to atmosphere.
iii. Cylinder bank : Required quantity of gas will be stored in seamless steel cylinders shall
have UL and CCE nagpur approval.
iv. The 200/300 bar Clean Agent storage cylinders shall be designed to hold Clean Agent at
ambient temperatures.
v. Minimum design level pressure of storage cylinder shall be 200/300 bar. The design
pressure for cylinder shall be suitable for the maximum pressure developed at 1300 F (550
C).
vi. The cylinders shall be charged to a fill density or super pressurization within the range
specified in the manufacturers listed manual.
vii. The total number of cylinders in the bank shall be determined depending on the volume of
the premises to be protected. Bidder shall select the capacity of cylinder based on the
storage space available and for effective replacement and inter changeability. All cylinders
in the Bank and reserve bank shall be interchangeable
viii. The cylinder shall be seamless and never retested, brand new never retested and month &
year of manufacture shall be latest.
ix. Each cylinder shall have a permanent name plate, specifying the agent, tare and gross
weight in addition to the pressurization level, nominal agent volume.
x. Cylinder shall bear the mark of manufacturer, serial number, single test certificate issued
by manufacturer and shall be duly approved by UL/FMRC/VDS/LPC.
xi. Cylinder shall conform to the requirement of NFPA 2001 (Latest Edition) and shall be
compatible with the engineered system being provided along with design analysis.
xii. Each cylinder shall have pressure relief valve to protect the cylinders against excess
pressure conditions. Pressure gauges with isolation valves on manifold shall be provided.
xiii. Automatic means such as check valve shall be provided to prevent agent loss if the system
is operated when any cylinders are removed for maintenance.
xv. In a battery of cylinders manifold together, leading to distribution piping and discharge
nozzles for the risk to be protected, including below false floor and above false ceiling
spaces, along with a reserve battery of Clean Agent filled cylinders with manifold and
directional valves, including arrangement for automatic change over to any of the two
banks after actuation of main cylinders to be provided in each risk area i.e. 100% reserve.
Reserve cylinders shall be connected to the main header, so that incase of successive fire
reserve bank can also be used.
xvi. The cylinder storage racks shall be provided for main as well as for reserve cylinders.
xvii. The manifold cylinders referred above shall be securely mounted on the floor and suitably
supported in a rack with provision for convenient individual servicing, according to the
manufacturers installation manual. Such servicing shall be possible without shutting down
the system.
xviii. The Bidder shall indicate the space provision for storage of Gas Cylinders and Manifold
Piping along with technical offer.
xix. The gas cylinders shall be provided with Base Plate, foundation bolts & nuts etc. so that,
the entire load is evenly spread out over the entire plan area. No concentrated load shall be
resulted from the mounting arrangement of the cylinder/containers.
xx. All the pressure, gauges/switches, manifold connections etc shall be easily removable for
servicing / maintenance without any loss of gas.
Discharge nozzles shall conform to NFPA 2001 (Latest Edition). The material of
construction shall be of Brass and shall be UL/FM/VDS/LPC approved. Discharge
nozzles used in the system shall be listed for the use intended for discharge characteristics.
The selection of nozzle orifice shall be such that 95% of the minimum design
concentration of gas is discharged within 60 seconds, through the nozzles of the system.
Each nozzle shall be permanently marked to identify the manufacturer as well as type and
Vol. – IIC, Section 04.00 FIRE PROTECTION SYSTEM Page 11 of 21
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TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION-I (4X210MW)
size of the orifice along with tag / part number, orifice code, or other suitable marking as
specified in relevant norms / codes.
Pipes shall be of ASTM A53 or A106 type (seamless carbon steel high pressure Schedule
80 pipes and pipe fittings shall be provided as per the requirements specified in NFPA-
2001 (Latest Edition).
All the pipes &pipes fitting, testing pressure, brusting pressure, etc. shall be designed and
tested considering supplied cylinder pressure as per NFPA -2001 (Latest Edition).
The Clean Agent piping and nozzles shall have to planned clearing following facilities
coming on its route, in the areas where protection is being envisaged:.
Path of AC ducts.
Cabling in false flooring.
Light fittings, detectors etc.
i. Operating devices shall include Clean Agent releasing devices or valves, discharge
controls and shut down equipment necessary for successful performance of the system.
ii. The automatic Clean Agent system shall be of robust design and shall not be readily
rendered inoperative easily. The Clean Agent system shall be designed to function
properly for the temperature range specified in NFPA-2001.
iii. The Clean Agent cylinders shall be mounted on front and firmly supported in brackets in a
manner that they will not be easily subjected to mechanical, chemical or other damage,
which would render the system inoperative.
iv. In addition to Automatic actuation, there shall be a normal manual control for actuation,
which shall be located so as to be conveniently and easily accessible at all times including
the time of fire. This control shall cause the complete system to operate in its normal
fashion.
v. Manual controls shall not require a pull of more than 40 lbnor a movement of more than
14 inches to secure operation. Each remote manual control for activation shall be located
not more than 4 feet above the floor.
i. The local control panel shall be free standing, floor mounted type and shall be suitable for
Vol. – IIC, Section 04.00 FIRE PROTECTION SYSTEM Page 12 of 21
© 2020 MECON Limited. All rights reserved.
TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION-I (4X210MW)
both auto and manual operation. The panel shall be naturally ventilated, totally enclosed,
dust and vermin proof, with IP-67 enclosure as a minimum. The Clean Agent system shall
be actuated automatically by the signal received from the fire alarm and detection panel.
Fire alarm and detection panel, after detecting the fire in the protected area / zone, shall
provide an actuating signal to Clean Agent control panel, which in turn shall energize the
solenoid valve to trigger the operation in the respective protected area / zone. The exact
location of local control panel shall be decided during the detailed engineering.
ii. Boosting up provision shall be done by the Bidder to get adequate power supply/ current/
voltage required to operate the solenoid valve, LDP and other component of FDA system
iii. The local control panel shall be equipped with adequate rating battery charger and Ni-Cd.
battery with 24 hour back up, for efficient operation of the system during mains power
failure.
iv. Control panel shall be provided with all alarms, indicators, caution/sign board and relays/
control switches meeting all the requirements of NFPA-2001 and shall include but not be
limited to the following:
a. Two alarms and one fault indicator lamp for each zone to be protected.
f. The system shall have a positive warning device by sounding alarm to alert
personnel of the impending discharge and also a positive indication to show that the
system has actuated.
h. All indication lamps shall be LED type with minimum size of 10 mm.
v. Warning and instruction signs at entrance to and inside protection areas shall be provided.
vi. A Control Box /Clean Agent Release Panel shall be provided for manual control at the exit
doors of each risk area, comprising of selector switches for selection of Main/Reserve and
Auto/Manual Push buttons for Clean Agent release.
vii. Potential free contacts shall be provided from the Clean Agent Control Panel to shut off
the fire dampers / louvers and Air Conditioning System.
viii. Supervision of automatic systems shall be provided and shall include electrical supervision
of the actuating device and the wiring connecting the actuation device and the detection
system.
ix. Visual display shall be flashing type and hooter system of distinct tone capable of being
heard in the range of 500m from the source.
x. Clean Agent extinguishing system shall incorporate a pre-discharge alarm with a time
delay, sufficient to allow personnel evacuation prior to discharge. The delay shall be
minimum 30 seconds. However it shall be adjustable from 30 to 120 seconds.
xi. Operating devices shall be by mechanical, electrical and pneumatic means conforming to
NFPA2001. The power supply to electrical actuators shall be backed up with reliable
battery supply. Such batteries shall be charged automatically by battery chargers. Power
supply is taken from the Fire detection alarm system panels of the respective units.
Required annunciation's such as "Gas released", "Failure of automatic actuation", "Gas
release aborted" etc shall be exhibited in the fire alarm panel.Gas release panel shall be
UL/FM/Vds approved
xii. Where pilot cylinders are employed for actuation of the cylinder banks, the number of
pilot cylinders shall be as per the listed design manual.
xiii. All manual operating devices shall be identified to the hazard they protect.
xiv. Manual abort switches for each of the area / zone shall be as per NFPA2001 or as
specified by listing authorities.
xv. The gas releasing devices at cylinder outlets shall be of reusable type after discharge at any
instant.
xvi. Supervision of automatic actuation devices, power supply, manual actuation circuits, and
complete wiring shall be provided through control system I panel and the healthiness shall
be reported or indicated in the panel automatically. Complete control system shall be listed
and approved by UL/FMRC/VDS.
xvii. Bidder shall consider the digital type static weighing machine for each cylinder. However
where system does not permit digtal weighing, then gas loss from each cylinder shall be
displayed on Local Gas Release Panel through actuation of pressure switch installed on
each gas cylinder as well as on Main Fire Alarm Panel. Bidder shall also provide one
trolley for each area.
The material of construction shall be as per this specification for the items specified. For
other items, the materials of construction used in the system shall be in accordance with
NFPA-2001 or as specified by the equipment manufacturer for the intended use (if the
same is not specified in NFPA-2001). The material of construction shall be UL/FM/VDS/
approved. The approval of the same shall be submitted at the time of bid submission.
04.07.06 Electrical
Bidder to include power supplied and control interlocking. All wiring – junction boxes,
push button station, indication lamps, hooters etc. shall be included into scope of Bidder.
All areas shall have illuminated board “FIRE – EVACUATE, GAS WILL BE
FLOODED”. Each area shall have hooter adjacent to illuminated sign.
Main fire alarm panel shall have annunciation for fire in above areas and after confirmed
signal (operation of two detectors) signal will be initiated for tripping of A/C system and
visual indication ‘START – FLOODING’ shall be there. From main fire alarm panel
signals shall also be initiated for illuminated sign / hooters of respective area.
Manual pushbutton of each area shall be located near exit and shall be break glass type
with attached hammer. Manual push button shall operate valve for flooding in respective
premises and as well as for connecting banks of gas cylinders to main pipe.
Bidder to develop logic for above and submit working scheme along with the tender. Any
interface devices required to hook up this system with the main fire alarm panel shall be
included by the Bidder as part of the scope as a whole.
One no. wall mounted annunciation board near cylinder bank shall be provided for
(duplicate) annunciation to facilitate manual operation of valves.
Each cylinder in the bank shall be fitted with a discharge head, which shall be connected
to a common manifold through high pressure connecting pipes of tubes. In case rigid pipes
are used for the purpose anti-vibration coils shall be provided. Gas Manifold shall be also
UL/FM/VDS/ LPCB approved only.
All cylinders in the battery and the common manifold shall be mounted and suitably
supported in a rack provided for the purpose. The rack shall be designed in such a manner
that servicing and checking of individual cylinders shall be convenient and the cylinders
are rigidly held in position. The design shall ensure no change / minimum possibility of
accidental discharge of cylinders.
Types, Quantity, installation and distribution Portable fire extinguishers shall be as per IS
2190-2010. Extinguishers bearing IS marking shall only be supplied.
1. All the extinguisher shall be as per IS: 15683: 2018 and ISI marked.
2. Mechanical Foam gas cartridge (9 liters) capacity shall have minimum class B rating of
89B & minimum class A rating of 2A.
3. Water type 9 liter Capacity (gas cartridge) shall have minimum class A rating of 2A.
4. CO2 Extinguishers shall be 4.5 Kg capacity and shall have class B rating of 34B. As the
capacity of the extinguisher has been reduced to 4.5 Kg from 6.5 Kg, Proportionate
numbers of extinguisher has to be increased as Per IS: 2190:2010
5. DCP Extinguisher capacity 6 kg (filled with UL listed urea potassium bicarbonate powder)
, and shall have minimum class B rating of minimum 89B .
6. IS: 15683: 2018 also govern the clean gas agent fire extinguisher hence capacity of the
extinguisher shall be 6 Kg with minimum class A rating of 1A class B rating of 55B .(
(Halotron / NAF PV/ HFC-36 / Fluoro ketone) .
8. Fire sand bucket shall be as per IS: 2546-1974 galvanised mild steel, capacity 10 litres.
9. All the fire extinguisher shall pass vibration test as per IS: 15683: 2018 & Fire
extinguisher shall be capable to mount in vehicles and moving equipment’s.
10. 2 no. Extra cartridge with each cartridge type fire extinguisher shall be provided.
11. Water, Foam & DCP shall be of cartridge type, Carbon dioxide and clean agent shall be
stored pressured type.
12. Additional 10% portable fire extinguishers of each categories shall be also included in
scope of supply for maintenance and replacement purpose
(vii) Copies of ISI approval/TAC approval/or other statutory authority certificates & Test
Certificates
(ix) List of 2 years operation and maintenance spares as well as fast wearing item along with
unit rates
(ix) Additional 10% portable fire extinguishers of each categories shall be also included in
scope of supply for maintenance and replacement purpose
(x) All the fire extinguisher shall bear ISI marked and it shall be as per latest relevant IS
15683.
04.08.02 Necessary tools, spanners etc. required for regular operation/ maintenance of the
equipment shall be supplied along with the equipment and shall be mentioned in the offer.
04.08.03 All equipment shall be so packed to avoid any damage during transit.
04.08.04 The Bidder shall guarantee satisfactory performance of all the equipment supplied by him.
04.08.05 No deviations or exceptions from this Specification shall be permitted without the written
approval of the Purchaser / consultant. Intended deviations if any, shall be listed by the
vendor on a separate sheet of paper at the time of bids submission and supported by
reasons for consideration by the Purchaser / consultant.
04.08.06 Compliance with this Specification shall not relieve the Bidder of his responsibility of
furnishing equipment and auxiliaries of proper design, materials and workmanship to
meet the specific operating condition
04.08.07 All the equipment shall be provided with test certificates. A certificate shall be produced
from Chief/ Dy. Chief controllerof Explosives, PESO, Nagpur in case of Carbon dioxide
extinguishers. IS/TAC approval shall be required for all types of extinguishers.
04.08.08 All portable extinguishers shall be supplied with mountings, accessories and installed
along the column/walls near entry/exits and at height of approximately 1000 mm from the
finished floor level. Wherever extinguishers are required to be installed on the steel
columns of the building, the welding of the supporting fixture to columns shall be done by
the successful Bidder. Necessary welding set for this job shall be arranged by the Bidder.
The Bidder shall mark / provide border around the fire extinguisher installing point / fire
point describing details as specified by fire officer in florescent paint. Self-explanatory
display board shall be provided depicting the type of fire & the type of suitable
extinguishers that is to be used.
04.09.01 Introduction
Passive fire protection is an integral part of a complete fire protection system and is
essential for prevention of spread of fire through openings in walls or floors. These
measures are intended to contain a fire in the fire compartment of origin, thus limiting
the spread of fire, excessive heat and corrosive, re-ignitable and fatal gases for a limited
period of time, as determined by testing, which must bound installed configuration in
all respects in order to comply with the law and regulations. Passive fire protection
system shall be provided as per indicated in Annexure-1 (refer electrical drawing indicated
in Sl. No. 3 to 7 in list of drawing enclosed portion).
For vertical run of cables & PVC conduits, fire retardant coating will be provided for
the whole length. For horizontal run of cables, 1 m length of fire retardant coating will
be provided at every 5.0 m interval wherever cables cross any partition wall, floor or
pass through any opening, coating shall be provided for at least 1 m length on either
side. In addition to this all the cable joints shall be coated with fire retardant paint all
around and or 1 m length both the side of joint. Fire retardant coating/ painting of
cables having minimum 3 hours fire rating. The material shall be UL/FM/VDS/LPCB
approved and enlisted. Approval for the material shall be obtained from CBRI,
Roorkee.
The system shall have minimum 3 hours fire rating ( It should have approval from
CBRI, Roorkee).Fire Stop materials shall have approval and certification from UL/ FM/
LPCB/ VDS.
04.10.01 Testing
All tests and inspection of the installation shall be done in conformity with the functional
and statutory requirement of the system. The bidder shall furnish a detailed testing and
commissioning procedure for all the systems for approval by the purchaser. As soon as a
given facility or a portion thereof is completed and ready to energize and start-up, the
purchaser may test run and operate it without relieving the Bidder of his responsibility or
guarantee.
i. Bidder shall provide the services of all technicians, erection and start-up engineers
necessary to bring the complete installation of hydrant / clean agent system etc. into
operation.
The Bidder shall be responsible for the integrated commissioning of the plant &
equipment supplied by him including trials, commissioning and demonstration of
performance guarantee test.
The Bidder shall be required to clean up the equipment and surrounding area and prepare
it for trial runs and operation.
The Bidder shall clean up dirt, remove any protective coating applied by the manufacturer,
clean ventilating open and remove all visible foreign bodies from the equipment erected.
Sequence checking of all control systems, pneumatic and cable connections, checking
operation of all interlocks and protective devices shall be done by the Bidder.
Blow down of all piping systems, installations and removing strainers in piping and
equipment, as required shall be done by the Bidder.
Vol. – IIC, Section 04.00 FIRE PROTECTION SYSTEM Page 19 of 21
© 2020 MECON Limited. All rights reserved.
TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION-I (4X210MW)
The Bidder shall provide personnel as required for assisting starting up and
commissioning of equipment as well as adjustments, repairs and rectifications of defects in
erection of the equipment during commissioning of the equipment and upto final
acceptance.
Trial runs shall be carried out after completion of erection and shall determine function
ability and the readiness of equipment to operate the plant erected. The plant shall be
tested in all its functions and checked for proper performance. Any irregularities found
shall be remedied by the Bidder.
Trail run shall be performed during the shutdown period which will be discussed mutually
and informed to the Bidder.
iv. Commissioning
On completion of the trial operation, all the systems shall be under observation in
operative condition. The Bidder shall provide skilled personnel including necessary tools
and consumables wherever necessary to rectify the deficiencies observed.
Verify and certify the material (equipment) offered meets all the details mentioned in the
specifications.
Welding materials/ rods shall be checked for meeting specifications/ standards. Wherever
radiography welding is required, the same has to be inspected (only for welding
applications).
PG Test shall be carried out within 3 months from date of commissioning of the system in
Vol. – IIC, Section 04.00 FIRE PROTECTION SYSTEM Page 20 of 21
© 2020 MECON Limited. All rights reserved.
TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION-I (4X210MW)
presence of METTUR-I and turnkey supplier of the system viz.hydrant system, Clean
agent gas system, Portable fire extinguisher, Passive fire protection.
The PG parameters shall be understood to be met if, the above mentioned system have
performed as per the technical requirement spelt out in TS.
Portable extinguisher shall be subject to WARRANTY for a period of 12 months from the
date of commissioning of the plant. The warranty shall cover defect, defect in material or
workmanship for sub-assemblies as well as the total assembled equipment Initial fill of
gas and other fire extinguishing media (including quantity required for PG test) shall be
under the scope of Bidder and quantity/item used for testing/PG shall be replenished by
the bidder free of cost.
In case it fails/deviates, from the TS, the bidder has to make it operable according to the
requirement of TS within a period of 2 weeks.
In absence of the above, Bidder shall be charged proportionate percentage of the L.D of
7.5% of the total contract price plus escalations, if any, paid or payable to the bidder
excluding taxes and duties.
The observations of each performance test shall be recorded and signed by the Purchaser
and the bidder. If such data conform to the performance test values, the performance
guarantee test shall be considered to have been successfully completed and a certificate to
this effect shall be issued by the purchaser.
The bidder shall be liable for the PG Test and meeting the requirement of
performance guarantee parameter of entire firefighting system as whole category
wise.
05.01 GENERAL
All valves (isolation / gate / globe / control) required for the FGD system, actuators for
the actuated valves as required.
05.02 The material to be supplied for completing the pipe work shall include but not be
limited to the following:
05.02.01 Straight piping, bends, tees, elbows, branches, laterals, crosses, reducing unions,
couplings, caps, blank flanges, saddles etc. necessary for making reliable piping
system.
05.02.04 Gate / plug, globe and check valves to start/stop, regulate and to prevent back flow.
05.02.05 Anchors, hangers and supports as required including secondary steel embedment etc.
05.02.06 Bolts, nuts, fasteners as required for interconnection piping, valves and fittings as well
as for terminal points.
05.02.09 The area around storage tanks, strainers, valves etc. (located outside pump house) shall
be paved
All piping shall be provided with vents at the highest points and drains at the lowest
points along with vent valves and drain cocks. Vents shall not be less than 15mm in
size. Drains shall not be less than 25 mm size. The piping shall be arranged to provide
clearance for the removal of equipment requiring maintenance and for easy access to
Vol. – IIC, Section 05.00 PIPE, VALVES & FITTINGS Page 1 of 2
© 2020 MECON Limited. All rights reserved.
TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
valves and other piping accessories required for operation and maintenance.
Pipe Size in pump suction side shall be at least one pipe size larger than the
corresponding pump discharge connection.
THERMAL
INSULATION, LAGGING
& CLADDING
06.00.00 General
Thermal Insulation along with aluminum cladding shall be provided for all the
equipments/surfaces having skin temperature more than 60 degree Celsius.
06.01.00 The specification of the insulation including type, density, thickness, heat
conductivity and finish shall be designed based on criteria specified below. The
insulation thickness shall be designed based on following criteria.
However, the minimum insulation thickness, however, shall not be less than 75 mm.
06.02.00 Material and application of insulation material, protective cladding, wire mesh
etc. shall be conforming to latest edition of following codes:
a) IS: 8183
b) IS: 3677
c) IS: 3144
d) IS: 14164
e) IS: 280
f) ASTM B-209
06.03.00 Insulation material for all equipments, ducting, etc. shall conform to following
requirements:
Parameters Requirement
i) Material a) Lightly resin bonded mineral
wool of best grade conforming to IS:8183.
(Handmade mattresses are not acceptable).
Material shall be rock wool only. Slag wool
Vol. – IIC, Section 06.00 THERMAL INSULATION, LAGGING & CLADDING Page 1 of 8
© 2020 MECON Limited. All rights reserved.
TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
06.04.00 The Insulation mattress shall be rated incombustible when tested by the method
prescribed in clause 15 of IS:3144 and shall meet the requirement of the Mercantile
Marine department, Lloyd's Register of shipping, underwriter, fire hazards codes and
other International standards.
Vol. – IIC, Section 06.00 THERMAL INSULATION, LAGGING & CLADDING Page 2 of 8
© 2020 MECON Limited. All rights reserved.
TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
a) Pass standard combustibility test both immediately after application and after subjected
to maximum operating temperature for not less than 100 hrs.
b) Not suffer permanent deterioration as a result of contact with moisture due to
condensation and shall be free from objectionable odor.
c) Not cause corrosion of the surface being insulated or of cladding on it under normal site
conditions.
d) Not suffer any quality deterioration under specified service conditions (both
cold/hot face temp.) of use.
06.07.00 The use of insulation of finishing materials containing asbestos in any form is
not permitted.
Sheathing material for all insulated surfaces, equipments, piping etc. confirming
to ASTM B-209-1060 temper H-14 or IS:737 Gr 19000/H2, shall be provided.
The thickness of aluminium sheathing to be used shall be 22 SWG (0.71mm).
06.10.00 Binding and lacing wires shall be 20 SWG Galvanised Steel wire
06.11.00 All Straps and bands shall be Galvanized Steel. Bands shall be 20 mm wide and 0.6 mm
thick. For securing Aluminum sheathing material, stainless steel or anodized
aluminum bends shall be used.
06.12.00 Screws shall be of galvanized steel, check headed, self tapping type. Above 400
degree Celsius temperature, screws shall be stainless steel.
06.13.00 Hexagonal wire mesh netting shall be 10-13 mm aperture and at least 0.56mm
diameter conforming to following Galvanized Steel wire.
06.14.01 Non metallic components like 3 mm thick mill board, aluminum pigment
sealant, white glass cloth, insulating cement, neoprene washer shall be provided.
Vol. – IIC, Section 06.00 THERMAL INSULATION, LAGGING & CLADDING Page 3 of 8
© 2020 MECON Limited. All rights reserved.
TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
06.15.01 General
a) All surfaces to be insulated shall be cleaned of all foreign materials such as dirt,
grease, rust etc. and shall be dry before the application of insulation.
b) Before applying the insulation the contractor shall check that all instrument
tapping, clamps, lugs and other connections on the surface to be insulated have
been properly installed as per the relevant erection drawing.
c) All flanged joints shall be insulated only after the final tightening and testing.
d) The insulation shall be applied to all surfaces when they are at ambient temp. Ample
provision shall be made for the maximum possible thermal movement and the
insulation shall be applied so as to avoid breaking/telescoping due to alternate periods
of expansion and contraction.
d) All cracks voids and depressions shall be filled with finishing cement, suitable for the
equipment operating temp. so as to form a smooth base for the application of
cladding.
06.15.02 All the refractory and insulation materials required for complete field application
of insulation, cladding etc. covered under these documents and specifications shall be
furnished with the equipment. They shall conform to the requirements of the various
relevant ISI standards or other approved equivalents. All items such as insulating
cement, sealing material, insulation material, screws, washers, etc., needed to
complete the work in the course of the application of insulation and refractory
shall be furnished. All insulating materials shall be chemically inert in both the dry and
wet state and shall withstand the full working temperature conditions to which
they are exposed without any deterioration. The gas ducts shall be insulated with
mineral wool block or mineral wool blanket and all other equipment operating at
elevated temp. not enclosed in the boiler casing shall be insulated with calcium
silicate blocks, mineral wool blocks or mineral wool blanket insulation.
a) All vertical pipes shall be provided with the suitable insulation supports to
prevent collapsing/crushing of insulation due to its self weight. Support rings shall be
provided on all vertical piping with a difference in elevation of 4 meter or
above, and there shall not be more than 3 m straight length between support
rings.
d) The mattress type insulation shall be formed to fit the pipe and applied with the
mattress edges drawn together at the longitudinal joints and secured by lacing wire.
Pipe section insulation shall be fitted on pipe using binding wires.
e) Where insulation is applied in two or more layers each layer of mattress shall be
backed with hexagonal wire mesh. For the first layer of insulation and in case of
single layer insulation, hexagonal wire mesh shall be provided on both the surface
of the mattress. For pipe sections, the sections shall be held in place by binding wires
without any wire mesh.
f) The ends of all wire loops shall be firmly twisted together with pliers, bent over
and carefully pressed into the surface of the insulation. Any gap in the insulation shall
be filled with loose mineral wool or finishing cement.
h) The insulation shall be held in place by fastening over with binding wire for
insulation surface with diameter upto and including 550 mm and with metal
bends for insulation surfaces with diameter over 550 mm. The fastening shall be done
at intervals of 250 mm except where specified otherwise. The ends of the binding
wires shall be hooked and embedded in the insulation. The straps shall be
mechanically stretched and fastened with metallic clamping seals of the same
materials as the strap.
i) Insulation for application on bends and elbows shall be cut into mitred segments,
sufficiently short to form a reasonably smooth internal surface. After the
application of insulation material place, insulating cement shall be applied as
required to obtain a smooth surface.
k) All pipe attachments coming on horizontal pipes, inclined pipes and bends shall
be insulated along with pipe such that there will be no insulation applied to hanger rod
and the component connecting hanger rod to pipe attachment. All pipe attachments
exposed to weather shall be provided with weather proof covering.
l) Upstream of all drain lines and the lines connected to steam traps, shall be
insulated upto and including first isolating valve for heat conservation. Rest of such
Vol. – IIC, Section 06.00 THERMAL INSULATION, LAGGING & CLADDING Page 5 of 8
© 2020 MECON Limited. All rights reserved.
TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
lines such as downstream of the drain valves, traps etc. and other lines such as
safety valve discharges, vents, etc. shall be insulated for personnel protection.
a) All valves fittings and specialties shall be insulated with the same type and
thickness of insulation as specified for the connected piping with the special provisions
and or exceptions as given below.
b) All valves and flanges shall be provided with removable box type of insulation covered
with box fabricated from aluminium sheets of thickness same as the connected pipe
cladding. Adjoining pipe insulation shall be bevelled back to permit removal bolts and
nuts or bands. The portion of the valve which can not be covered by box type
insulation shall be filled by loose insulating material of packing density at least
equal to that of the insulating material of adjoining pipe. The insulation for
valves/flanges shall be applied after the finishing has been applied over the
connected piping. The cladding shall be applied in such a manner that the bonnet
flange can be exposed easily without disturbing the complete insulation and cladding.
c) Flanges on lines having temperature upto and including 150 deg.C shall not be
insulated.
a) Provide expended metal or hexagonal wire mesh on both sides for single layer
mattress and on first layer in case of multilayer insulation. Subsequent layers of
multilayer insulation to have only one side wire netting.
c) Any gap between joints between insulation layers shall be filled by loose mineral
wool confirming to IS:3677.
d) All insulation to be secured by 1.63 mm dia wire netting over blankets with
ends of wire tightly twisted, and pressed in to insulation surface.
Vol. – IIC, Section 06.00 THERMAL INSULATION, LAGGING & CLADDING Page 6 of 8
© 2020 MECON Limited. All rights reserved.
TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
06.17.00 Flue Gas ducts with external stiffeners shall have first layer of insulation between the
stiffeners and a second layer of insulation over stiffeners so that stiffeners are also
insulated and a level surface is achieved. Other requirements are same as given in
Clause 06.09.00.
06.18.01 All insulated surfaces of the FGD shall be provided with metal cladding in
accordance with the following requirements.
a) All insulation procedure of metal cladding shall have prior approval of the
Purchaser
c) Cladding for FGD components are to be finished with plain aluminium sheeting
of thickness not less than the values specified. Wherever an inner casing plate is
necessary to effect a gas tight enclosure, the plate shall be of mild steel of required
thickness, but not less than four (4) mm suitably stiffened and supported.
06.19.00 Application
All metal cladding shall be fabricated and installed to ensure a neat appearance and no
open ended sections of cladding shall be left uncovered. The following provisions shall
also be complied with:
a) All closures, flashings and seals required shall be provided and installed.
b) An asphalt and craft paper moisture barrier shall be provided to the aluminum
cladding for all out door applications. Such moisture barriers shall be fixed to the
inner surface of the cladding or shall be cemented to the outside surface of the
insulation before application of cladding.
c) All the used in the out door cladding shall be provided with Neoprene washers.
Vol. – IIC, Section 06.00 THERMAL INSULATION, LAGGING & CLADDING Page 7 of 8
© 2020 MECON Limited. All rights reserved.
TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
d) All openings and joints in outdoor cladding for piping connections, supports or
access shall be suitably flashed and weather-proofed. Where such flashings or
weather-proofing cannot effectively control the entry of moisture, then such openings
and joints shall be weather-proofed by application of aluminium pigmented sealer.
e) Cladding on the top surfaces of the FGD, duct work and equipment shall be suitably
reinforced to prevent damage by personnel walking thereon.
Vol. – IIC, Section 06.00 THERMAL INSULATION, LAGGING & CLADDING Page 8 of 8
© 2020 MECON Limited. All rights reserved.
SECTION 07.00
COMPRESSED AIR
SYSTEM
07.01.00 General
Oil free screw type air compressors, desiccant type air dryers along with air receiver
having suitable capacity for the FGD plant shall be provided.
The scope of work of the bidder shall cover design, engineering, manufacture, shop
testing, painting, supply transportation to site, storage, handling at site, erection, testing,
commissioning, demonstration of performance parameters and final handing over of all
the plant & equipment and connected utilities of compressed air system.
The compressors, air dryer units and air receivers shall be complete with all materials
and equipment whether specifically mentioned herein or not but required for
satisfactory operation of plant & equipment individually as well as integrated manner.
At the outlet of compressor flow measurement shall be envisaged & same shall be
indicated in the control room or may be hooked up with PLC system, Suitable hoisting
facility for maintenance purpose shall be considered.
The compressors along with air dryer shall be located inside a structural building near
main plant.
Compressed air station shall comprise of but not limited to the following main units:
a) Oil free, air/ water cooled, rotary screw packaged type air compressor complete with
electric motor of suitable capacity and all its accessories & auxiliaries along with pipes,
fitting, valves, etc including the following accessories / auxiliaries to meet the
requirement of service/ instrument quality air for the entire FGD plant. The
specification of air compressor, air dryer unit and air receiver are indicated here in after.
d) All necessary interconnecting pipes, valves, fittings including supports and supporting
structures.
Vol. – IIC, Section 07.00 COMPRESSED AIR SYSTEM Page 1 of 5
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TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
e) Drain pipelines from compressed air station to nearest drain / drain pit.
f) Necessary electrics, instrument & Controls for compressors, air drying unit and air
receiver & its auxiliaries.
h) All anchor bolts & nuts, washers & base frame for equipment.
Installation : Indoor
Environment : Dusty
07.03.02. Compressor shall be complete with motor of suitable capacity. Driving motor shall
have adequate margin not less than 10% over the maximum power requirement at
motor terminal (considering motor efficiency) at maximum capacity of the compressor.
07.03.03. Suitable lubrication system for bearings and other moving parts of the compressors
shall be provided. Lubrication system shall be complete with necessary filters /
strainers, oil coolers, level indicators, pumps, pipes, valves and fittings etc.
07.03.04. Compressor shall be provided with a dry type air intake filter system. The suction filters
supplied shall be of appropriate type such as to prevent ingress of dust into the machine.
07.03.05. The compressor shall have capacity control with constant discharge pressure over full
range. For this purpose suitable air intake control valve with other connected system
shall be provided.
Vol. – IIC, Section 07.00 COMPRESSED AIR SYSTEM Page 2 of 5
© 2020 MECON Limited. All rights reserved.
TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
07.03.06. Compressor shall be provided with inter cooler, moisture separators etc..
07.03.07. Compressors shall be provided with adequate safety, protection and control system.
There shall be desiccant air drying unit of suitable capacity. Selection of dryer shall be
such that performance of the same shall not be affected at different loads of the system.
This dryer shall be installed adjacent to the compressor. The system shall be designed
such that under no circumstances the dry air supply shall be stopped.
The air drying and filtration shall be designed to continuously supply dry and oil free
air. Both manual and automatic change over from one mode to other should be possible.
The design, fabrication and materials of construction of various pressure vessels shall
be as per the pressure vessel code IS:2825 latest edition or ASME Section VIII.
Pre filters shall be provided to remove dust and any other contaminant from the air
stream. After filters located downstream of the absorber towers shall prevent carryover
of fine particles with the efficient air stream.
Both the pre filters and after filters shall have 100% standby unit. All filters shall have
individual isolation valves, safety valves and drains with trap stations and pressure
gauges.
The air drying plant shall be provided with dew point measuring devices.
The dryer shall be supplied along with all necessary auxiliaries. The operation and
controls of the dryers shall be fully automatic.
The dryers shall have built control panel with auto / manual operation. Indication of
outlet air temperature and pressure shall be provided at prominent place. Lifting eyebolt
shall be provided for installation and maintenance purpose. First fill of all consumables
shall be supplied along with the dryer unit.
There shall be suitable capacity of air receivers for service/ instrument air. Air receivers
shall be of carbon steel material, welded construction complete with all accessories.
The air receiver shall conform to IS:7938 latest edition. The air receivers shall be
designed, manufactured and tested according to IS:2825 latest edition and shall be
complete with pressure gauge, lifting lugs, manhole, safety valve and foundation bolts.
The material of construction of shell, header, nozzle, etc. shall be as per IS – 2002 – Gr.
– 2A or equivalent.
Piping layout must follow good engineering practices. Proper attention shall be paid to
obtain full functional requirement of air, water and oil piping with a layout which
provides sufficient clearance for various auxiliaries, other equipment and operating
personnel, easy access for operation and maintenance, convenient supporting
arrangement.
Except otherwise specified, all pipes shall be provided with butt welded connections
and with flanged joints only at the connections with equipment, vessels and valves.
Pipes laid inside the R.C.C. trenches shall be supported at intervals on steel sections
and the arrangement shall facilitate easy maintenance.
Valves in the air line shall be of shall be of cast steel / forged steel full bore, two / three
piece design ball valves with Stainless steel internals. For waterlines, either wafer type
butterfly valves sand witched between two flanges or double-flanged butterfly valves
shall be provided. In butterfly, gate, globe valves, face of the hand wheel shall be
clearly marked with word `open and shut' with arrows adjacent to indicate the direction
of rotation. In butterfly, non-return & globe valves, direction of flow shall also be
marked on the valve body.
All the globe valves shall be designed to prevent erosion of valve seats when the valves
are operated in throttled conditions. Design of valves shall be such that it shall permit
packing of glands while under pressure.
Non return valves shall be of double flanged and dual plate spring design.
The solenoid valves shall have heavy duty, double impregnated tropicalised coil and
shall be suitable for operating temperature and for operation continuously energised in
tropical climate. The solenoid valves shall be of bronze body with stainless steel trim.
Vol. – IIC, Section 07.00 COMPRESSED AIR SYSTEM Page 4 of 5
© 2020 MECON Limited. All rights reserved.
TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
The coil shall be suitable for continuous duty. The enclosure shall be water tight, dust
tight and the valve shall be suitable for mounting in any position.
All the valves for water line and air line shall be of 150 class rating. The valves with
flanged ends shall be provided with flanged ends having raised face, serrated finish.
The drilling of the flanged ends shall be done as per IS:6392 - 1971 (RA 1988) .
All pipelines shall be provided with drain connections, generally at the lowest point for
removal of accumulated condensate or water and also for draining of the water after
hydro testing of the erected pipe work. Vents with valves shall be provided at highest
point of the pipe line.
The drain piping shall have drain pocket followed by a connection of drain pipe with
isolation valve. Line shall be provided with slope towards the drain point.
MS Pipes of following specification shall be provided for industrial water and air
applications.
NB 15 - 150: ERW, Black, Heavy pipe having plain ends as per IS:1239 Part-I – 1990.
NB 150 & above: ERW, Black pipe of minimum thickness 6.35 mm having plain ends
as per IS:3589-1991
Pipe fittings conforming to IS:1239 Part-II - 1992 shall be provided for pipes of size up
to NB 150. Fabricated fittings manufactured from the pipes shall be provided for pipes
of sizes NB 200 and above.
Complete pipe network after erection shall be hydraulically tested at a pressure of 1.5
times the working pressure. The pipe network shall be subjected to the test pressure for
a minimum period of 4 hours.
TENDER SPECIFICATION
FOR
SEMI DRY FLUE GAS DESULPHURIZATION
(FGD) SYSTEM & ITS AUXILIARIES
VOLUME – III
MECON LIMITED
RANCHI – 834 002
INDEX TO VOLUMES
Volumes Title
Volume – I Commercial
Volume – II Technical
Volume - IIA General Technical Specification
Section 01.00 Preamble
Section 02.00 Intent of specification
Section 03.00 Project information
Section 04.00 Special instructions to Bidder
Section 05.00 Scope of work, supply & Services
Section 06.00 Quality Assurance system / Requirement
Section 07.00 Painting
Section 08.00 Finalization of sub-vendors / sub-contractors
Section 09.00 Performance Guarantees
Section 10.00 Terminal points & Exclusion
Section 11.00 Layout and maintenance requirement
Section 12.00 Drawings / Documents to be submitted along with Bid / Offer
and after award of contract
Volume -IIB Technical Specification
Section 01.00 Flue Gas Desulphurization System
Section 02.00 Technical Data Sheets – Mechanical
Volume -IIC Balance of Plant (BOP)
Section 01.00 Water Supply Facilities System
Section 02.00 Air conditioning & Ventilation System
Section 03.00 Elevators, Cranes & Hoists
Section 04.00 Fire Protection System
Section 05.00 Piping, Valves & Fittings
Section 06.00 Thermal Insulation, Lagging, Cladding
Section 07.00 Compressed Air System
Volumes Title
Volume - III Instrumentation & Control System
Volume -IV Electrical System
Volume -V Civil, Architectural & Structural Works
Volume -VA Civil Works.
Volume -VB Architectural Works
Volume -VC Structural Works
Volume -VI Mandatory Spares and Tools & Tackles
Volume -VII Tender Drawings
01.01.00 General
01.01.01 Introduction
Instrumentation & Control system for semi dry (hydrated lime) based FGD system for
MTPS-I (4 x 210 MW) has been envisaged with centralized, dedicated automated and
safe control system to achieve efficient and better reliability and availability of the plant
and equipment. This chapter covers the design criteria and concepts proposed for the
FGD System:
b. Smart type field instruments for the FGD plants & its auxiliaries.
c. Power Supply Equipment
d. Air Supply for pneumatic equipment.
e. CEMS Analysers
Flue Gas Desulphurisation (FGD) system and its auxiliaries shall be operated, monitored
and controlled through dedicated 1:1 hot redundant PLC system for each unit with all
closed-loop set in auto-mode. Sequencing, interlocking, protection and logic functions
shall be implemented in the PLC. No stand-alone PID controller for closed loop control
shall be envisaged. The C&I system shall be configured in fail-safe mode of operation.
This specification shall be read together with the Complete Technical Specification and
all the applicable clauses shall be complied by the Bidder while finalising the complete
scope of work & supply for this system.
Measurement and control equipment offered for the process shall be complete in all
respect in line with the broad requirement indicated in this specification. Any equipment
/ accessories not explicitly indicated in this specification, but considered essential for
proper functioning of process & equipment shall be included by Bidder in their scope of
work and supply.
Bidder shall refer the following clauses for the detailed technical specifications of
control and instrumentation facilities i.e. field instruments, analysers, cables, PLC,
control valves etc.
i. The scope of supply & work shall be complete design, engineering, procurement,
manufacture, assembly, inspection, supply, packing, transit insurance, transportation
to site, storage, calibration, erection, testing and commissioning of the complete
control & instrumentation (C&I) system with all types of field instruments, cables,
pipes and erection hardware necessary for completion of C&I work for the FGD
system & their auxiliary units on a turnkey basis.
ii. The scope of work shall also be complete with all civil work like chipping, digging,
concreting, including filling material etc., and associated erection of instrumentation
equipment where ever required.
iii. Bidder shall consider and provide air conditioned and well ventilated rooms for all
analyzers including CEMS. Suitable enclosures (as applicable) shall be provided for
all outdoor analyser equipments.
iv. One number portable type gas analyser shall be supplied for each flue gas analyser
system.
v. Each flue gas analyser syetm shall be supplied with necessary softwares alongwith
Laptop for configuration and calibration and required Reference gas cylinders with
license.
vi. In the event of conflict between requirements of any two clauses in any
volume/part/chapters/section of the tender specification, the more stringent
requirements shall apply. Purchaser, however, reserves the right to relax this
condition at his discretion.
vii. Parallel redundant dedicated UPS 240V AC,50Hz system along with battery backup
for PLC, analyzers, field instruments and all C&I systems & equipments, along
with ACDB containing redundant adequate nos. of feeders for C&I system shall be
provided (For detail refer TS in Electrical Volume).
viii. Bidder shall provide vibration measurement system. Accelerometer type 4-20mA, 2
wire with vibration sensor for the HT drives of FGD system and shall be hooked up
with PLC.
ix. A minimum conventional (vertical) back–up panel mosaic grid type mounting of
miniature push bottoms, trip switches with LED indication for operation of
CONTROL & INSTRUMENTATION SYSTEM Page 2 of 119
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METUR THERMAL POWER STATION-I (4X210MW)
start/stop of pump & motors considering major drives for safe operation & shut
down of the FGD plant.
x. All impulse pipes/Tubes after root valve shall be of SS as per application for field
instrument hookup.
xi. Any single failure of the field instruments or control equipment will not affect the
performance of the unit in any way. For field instruments /hardware configuration
following guidelines will be followed:
• For very critical application like for control & protection application of FGD unit
field instruments shall be provided 2 out of 3 hardware configuration.
• For balance control loops, protections, sequential logic and related measurement,
redundant hardware will be used.
• For balance measurement non-redundant hardware shall be used.
xiii. Close loop & open loop logics to be incorporated in Boiler logics due to
introduction of FGD system.
xiv. Maintenance platforms and access ladders for instrumentation equipment installed
at inaccessible heights.
xv. The purchaser reserves the right of selecting the manufacturer / model of control &
instrumentation items in the interest of standardization wherever necessary and the
Bidder shall agree to supply equipment/instruments of particular make if so desired
by the client within the list of approved vendors without any cost implication.
xvi. Any C&I equipment/instruments required during any stages for the efficient / safe /
reliable operation of the plant either during detail engineering / commissioning shall
be supplied, installed and commissioned by the successful Bidder without any
additional cost.
xix. Master clock signal shall be provided by purchaser (MTPS-I) at the GPS panel
located in the main plant control room for time synchronization with the FGD
systems. All the cables & hardware required for establishing the connectivity with
the main plant GPS shall be under the scope of the contractor.
xx. UPS power supply required for the FGD loads located at the main plant control
room (like RIO panel, OWS etc) shall be provided by purchaser (MTPS-I) in
ACDB. Further distribution from the ACDB including DB, Fuses, cable etc shall be
under the scope of the bidder.
xxi. Hardwire Signal exchange that is required with the main plant control system for the
critical signals shall be under the scope of the contractor including the cabling and
termination at both the ends.
xxii. It is envisaged that certain FGD drives shall also be controlled from the main plant
control system as decided during detail engineering in addition to the FGD control
system. IO’s required for these signals are also to be considered by the contractor.
Cabling & termination at both the ends i.e between FGD PLC & respective unit
control system shall be under the scope of the contractor.
Co-ordination with purchaser for software modification and development for
interfacing with main plant control system shall be under the scope of the bidder.
xxiii. The Bidder shall provide Air condition based PLC Equipment Room, FGD Control
Room, PLC RIO Room with granite flooring & metallic/metal plank false ceiling
with adequate lighting/LED bulb, emergency lighting etc. Control room shall be
aluminum framed, toughened glass partitioned for housing PLC control panels,
windows, main entrance double door and single door.
xxiv. Control room height shall be maintained minimum 3.5m upto the false ceiling and
over all height of control room shall be approx. 5.0 mts.
xxv. All instrument cables shall be routed through cable vault/gallery with maintaining
minimum height of 3.0meter.
xxvi. The measurements and controls indicated is the minimum requirement for the FGD
system. Bidder shall engineer the system and shall include additional measurements,
controls and protections required to make the system complete in all respects for
safe, efficient, reliable & ease of operation. Any measurement / control not listed
but essential for completeness of the process in total shall also be covered under the
scope of the Bidder.
01.01.04 PLC system envisaged shall include but not limited to the following:
The bidder shall provide modular furniture including chairs for the work stations &
suitable tables for the printers supplied by them.
The FGD system shall be operated, monitored and controlled through dedicated 1:1 hot
bump less PLC controllers, located in the FGD common Control Room. PLC shall have
redundant in following level as per plant configuration.
• Controllers (CPU).
CONTROL & INSTRUMENTATION SYSTEM Page 5 of 119
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METUR THERMAL POWER STATION-I (4X210MW)
• Communication modules
• Networks
• Power supply modules
• N/W switches, bus and connectivity including cables
• Critical I/O modules
The plant control systems shall be capable of controlling and monitoring the entire
functional unit by executing all functional requirements. The control system shall have
provisions to allow the operations such as change-over of stream, valve operations from
the control room, without need to go to local.
The philosophy shall be such that the plant shall be operated and controlled from hot
redundant PLC controllers with all closed-loop set in auto-mode. Sequencing,
interlocking and logic functions shall be implemented in the PLC.
PLC shall have the data acquisition of the process parameters of various plant units,
which can also be used to generate various reports for Management Information System
(MIS).
The visual display of the workstation provides various colour graphics of the plant
process, which are dynamic and real time to plant operating conditions. The keyboard &
mouse of the workstation enables the operator to provide the set-points and commands
to control the process.
Remote Input-Outputs (RIO) concept has been envisaged. The RIO generally consists
of the field input-output cards, communication interface module, power supply unit
arranged in a cabinet. Redundancy shall be provided at communication module,
communication network, and power supply. RIO / remote controllers shall be located at
different geographical locations and shall communicate to the PLC located in the
control room, through dual redundant communication links. Failures of RIO shall be
annunciated in the PLC.
The number of RIOs and its location shall be decided during detail engineering.
The RIO / remote controller panels shall be located in the air-conditioned room.
However the remote I/O system shall be so designed that it functions well even when
there is no air conditioning.
Operator’s interface to the plant and process is on Human Machine Interface (HMI)
which is a PC based workstation with HMI software. The Bidder shall provide
• Eight (8) nos. Operator work stations (2 nos. for each unit).
• Two (2) nos. Operator cum engineering station.
• One no. (1) Operator Station for each unit shall be placed at their respective
main plant control room
• Two (2) nos. A4 B&W laser printer.
• One (1) no Laptop with Engineering & HMI software loaded for FGD system.
• One (1) no A3 Colour Laser Printer.
• Two (2) nos. operator station with LVS 70”LED type common for all unit
• One (1 No.) Historian Station
• One (1 No.) OPC Station
01.02.01 PLC System Panel Hardware configuration Design for each FGD system
i) Separate Interposing Relay Cabinet with relays of 24V coil and contacts
(2NO+2NC) with LED indication.
ii) Power supply for SOV shall be 24V DC or 230V AC as per application and shall
be finalized during detailed engineering.
iii) For LT, HT, MOV drive control philosophy number of I/Os shall be considered as
per Electrical Technical specification.
iv) All DO signal shall be terminated through fuse TB.
v) Marshalling or Field wire shall be terminated through Field Termination Units
(FTU) for DI, DO, AI and AO shall be supplied separately. Alternatively, if it is
the standard practice of the PLC vendor to provide FTUs in the PLC cabinet, the
same shall be finalized during detail engineering.
vi) Mounting of cards on sides of PLC cabinet shall not be accepted.
vii) From base plate minimum 200-250 mm gap shall be provided in PLC cabinets.
viii) 24V DC, 230V AC UPS and 230V AC non UPS supply shall be provided
separately in Panel.
ix) A dedicated Panel (DB) for Power supply distribution shall be provided with
proper rating of MCB and shall be finalized during detailed engineering stage.
x) Dedicated Network panel shall be provided for switches and networking and
network switches shall be from approved vendors.
xi) For critical I/O consideration all Inputs shall not be located in same card and shall
be distributed in other cards.
xii) 20% spare installed I/O channels on each card level.
xiii) 10% spare installed I/O module
xiv) 20% spare TBs space for wiring in future
xv) No field wire shall be directly terminated to the I/O card (Like DI, DO, AI, AO)
without isolators/barriers/FTU (Field terminal units)
xvi) Multiple window facilities/face plate shall be provided in all the operating stations.
xvii) Separate modules shall be provided for RTD and Thermocouple.
xviii) Software details shall be submitted along with Part no. and with latest version etc.
xix) Integral SOE in PLC (min.128 points) with 1msec time stamping at card level
shall be provided.
xx) SOE/Report/Long Term data archival package/self documentation/test
function/standard builder function/Alarms shall be provided for all operating
station as well as Engineering Station.
xxi) Online Auto/manual tuning of PID controller with plant performance monitoring
package shall also be facilitated.
xxii) SOE can be viewed from all the workstations and shall be time synchronized over
GPS master Clock.
xxiii) Logic chart, control loop display / Trending / Graphics / electronic documentation
History / Alarms software shall be provided for all operating stations as well as ES
cum operating stations.
xxiv) History for 3months shall be available in all OS as well as ES.
xxv) Desks / Boards / Panels / Cabinets / enclosures wiring and piping shall be arranged to
enable the removal of instruments/devices without unduly disturbing them.
6.2 Analog input Modules Analog input units shall have the following
features:
• Shall be 4 / 8 channels, rack based & plug–in
type..
• Suitable for 4-20 mA / 0-10V DC / RTD /
thermocouple / weighing signal inputs.
• With necessary A/D converter having at
least12
/ 14 bit resolution based on application.
• Suitable for J/K/S type thermocouples & for
PT100, 2- wire / 3wire
• Galvanically isolated differential inputs.
• For 4 – 20 mA analog inputs, fused T.B with
blowing fuse shall be provided.
• Healthiness of every input shall be monitored
& LED indication shall be provided.
• Analog module shall have the facility to be
configured in voltage or current mode and
differential or single ended inputs mode.
• All the cards shall be compatible of receiving
analog signals from field sensors and
switches directly . If not suitable converters
shall be provided.
7.0 Output units - High density, modular.
- Insulation level of 500 / 1500 VAC/DC
- Individual DP MCB shall be provided in power
supply for each card
- Cards shall have diagnostic features
- Cards shall have hot swapping features
7.1 Digital Output modules Digital output units shall have the following
features:
• 16 / 32 digital outputs per module.
• High Density modular and plug-in type.
• Isolated outputs with two separate terminals
for each outputs.
• Rated for 24 VDC
• The output module shall be able to drive
interposing relays (24V DC coil) with 2
NO+2NC, solenoids, annunciation lamps,
LEDs, Instrumentation control equipmentetc.
• Power devices like contactors etc. shall be
actuated through interposing relays (2 NO+2
NC). The interposing relays shall be mounted
in the same panel. Proper surge suppressor
shall be mounted across the coil of the output
relays.
• Any special requirement e.g position control
to control field devices shall be met by using
separate interface modules.
- BCD output units shall be as follows:-
• Suitable for four-digit output.
• Rated to drive seven segment LED displays
7.2 Analog output modules Analog outputs shall have the following features:
• Shall be of 4 / 8 analog output channels.
• Suitable for 4-20 mA / 0-10V DC / +/-10V
DC outputs .
• With necessary D/A converters having 12 bit
resolution
• Each output shall be galvanically isolated.
Following are indicative list of measurement & control shall be provided by the Bidder
for this system. Any other measurement & control though not included in the list but
required for safe & proper operation of the process & equipment as per the offered
system of the Bidder shall also include in their scope and highlighted in their Offer.
Unless specified, all the measurement, control, alarm & interlock shall be achieved in
the PLC.
1. 2 Nos. of SO2 analyzers with Nafion dryer in each ID fan outlet (inlet duct to absorber)
duct
2. Pressure measurement (3 nos.) at the flue gas inlet (unclean) duct to absorber.
3. Temperature measurement at the flue gas inlet (unclean) duct to absorber.
4. Temperature measurement (3 nos.) at the top of absorber.
5. Pressure measurement (3 nos.) at the top of absorber.
6. RH (% H20) analyser offline (Lab).
7. Pressure measurement before recirculation slide 1 of absorber.
8. Pressure measurement (7 points.) at the bottom of absorber before discharge hooper.
9. Differential pressure measurement in between flue gas scrubber line and booster fan.
10. Pressure measurement at the inlet of booster fans.
11. Temperature measurement at the inlet of booster fans.
12. Pressure measurement at instrument air header line.
13. 2 Nos of SO2 analyzers with Nafion dryer in the clean gas duct at the outlet of absorber.
14. Level switch of each chutes below absorber hoppers.
15. Water tank level measurement & its control.
16. Water tank temperature measurement.
17. Differential pressure measurement across strainers (2 nos).
18. Pressure measurement at the common header of high pressure pump 1 & 2.
19. Flow measurement at the common header of water injection line to absorber.
20. Flow measurement of water tank return line.
21. Pressure measurement of water tank return line.
22. Instrument Air header pressure measurement.
23. Bearing temperature measurement of each Booster fans & its motors.
24. Bearing vibration measurement of each Booster fan & its motor bearing.
B. Fabric Filter
C. Re-circulation slide I
D. Re-circulation slide II
1. Level measurement & its control by regulating lime storage silos discharge gate.
2. Temperature measurement of lime storage silos.
3. Level measurement & its control by regulating by product silos discharge gate.
4. Temperature measurement of by product storage silos.
5. Necessary measurements and controls of lime conveying and compressor system.
6. Necessary measurements and controls of by-product conveying and compressor system.
7. pH and level measurement & control of mixing tank.
F. Chimney
Complete CEMS measurement system suitable for the semi dry flue gas parameters shall
be provided in the Chimney as per latest Central Pollution Control Board (CPCB) guide
line Aug, 2018 rev01. As a minimum Sox, Nox, CO, CO2, Hg, SPM, O2, Flow,
Temperature & Pressure measurement shall be provided.
01.04.00 All pump’s manual suction valves shall be provided with open limit switch. Automatic
starting of stand-by pump during any operational problem of the working pump shall be
considered, as applicable. To achieve the same, low header pressure alarm conditions
can be considered. Though not specified above, all process alarm & interlock functions
shall be suitably considered by the Bidder for safe & reliable operation of the process &
equipment. Make-up water pumps and waste water pumps shall have necessary
interlocking facilities including measurement of flow and pressure.
01.05.01 Pressure, Differential Pressure, Level (DP Type) and Flow (DP Type) Transmitters
(PT, DPT, LT & FT)
type medium
- Type Flush Type
- Process Connection ½” NPT / Flanged SS316 Class 150
- Material SS316L
Capillary Length Minimum 10 m
Mounting bracket For all transmitters
Drain & vent points As per requirement
1 No. of universal type hand held/portable HART calibrators shall be supplied for
calibration / configuration of Transmitters & other HART based instruments.
Accessories
- M33 x 2 in general
Process Connection - Flanged for Air & Gas systems with mating
flanges.
Within + 10 mm of center line of pipe subject to
sizing calculations such as frequency ratio, cyclic
Immersion Length
stress, dynamic stress, pressure limit. Etc. as per
PTC 19.3TW 2010
Minimum 100 mm above insulation of pipe and
Extension neck length Minimum 160 mm when there is no insulation on
pipe.
Thermo well Sizing Bidder shall provide sizing calculations for thermo
Calculation well as per ASME – PTC-19.3 TW 2010
Sheath 8 MM OD
Sheath Material 316 SS
Shall be spring loaded to ensure positive contact
with the well. Prevention of rotation of the insert
Terminals with respect to head and resultant twisting of leads
shall be ensured. Nickel plated brass-screw type/
silver plated
Nipple/Union required
Packed connector Compacted magnesium Oxide ungrounded
Element Size / Wire Gauge 16 AWG (for K type)
CONTROL & INSTRUMENTATION SYSTEM Page 26 of 119
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CORPORATION LIMITED (TANGEDCO)
METUR THERMAL POWER STATION-I (4X210MW)
M33 x 2 in general
Process Connection SS316 Flanged, for Air & Gas systems, with
mating flanges.
Threaded union (SS316) 1/2" NPT (F) with two
Extension nipples of SS 316 having 1/2"NPT (M) threads at
both ends
Within + 10 mm of center line of pipe subject to
sizing calculations such as frequency ratio, cyclic
Immersion Length
stress, dynamic stress, pressure limit. Etc. as per
PTC 19.3 TW 2010
Minimum 100 mm above insulation of pipe and
Extension neck length
Minimum 160 mm when there is no insulation on
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pipe.
Bidder shall provide sizing calculations for thermo
Thermowell Sizing Calculation
well as per ASME – PTC-19.3 TW 2010
a) Adjustable nipple-union-nipple {1/2” Sch.
80 X1/2“ NPT (M)} with thermo well
connection
b) Compression fittings/union
c) Flanges etc. (For flanged connection
only), Bolts, nuts and gaskets for flanged
Accessories
connections
d) SS 316 forged/barstock thermo well as
per ASME PTC code. Process
connection M33X2 (M)in general or 1½”
Flanged for Flue gas/ Furnace air etc.
application
Thermowell
1. Thermowells shall, in general, be of SS 316 and shall be drilled from bar stock except
for air and flue gas services. However, selection of thermowell material shall as per
following guideline.
2. The thermowell immersion depth (U) shall be sufficient to eliminate conduction error. A
general rule, which may be followed, is to use an immersion length equaling a minimum
of 10 times the diameter of the protective tube or well. In general, immersion length of
thermowells for different line sizes shall be as follows:
Immersion length is based on 200 mm length between flange face and inner wall of pipe.
In vessels, where fouling with vessel internals is expected, the immersion length shall
suitably modified. Any pipe less than 4” nominal bore shall be blown to 4” size.
Type/Construction
- Thermometer : Industrial type, Inert Gas Filled type with
separable thermowell Bimetallic & all angle
tiltable
- Thermowell : Bar stock
Material
Sensing material type : Bimetal strip helix
Connection
- Pipe : M33 x 2
-Thermowell : To suit instrument
Other Particulars
- Capillary length : Minimum 5 meters for local mounting & minimum
10 Meters for panel mounting
- Immersion Length : Within + ten (10) mm of center line of pipe with
adjustable nuts subject to sizing calculations as per
PTC 19.3 TW 2010
- Extension neck length : Minimum 50 mm above insulation of pipe/As per
approved hookup drawings.
- Stop or pointer at Maximum : For all gauges of scale with externally adjustable
value
: Contact type Temp. gauges are not acceptable for
interlock & protection.
- Over range protection : 150 percent (%) of full scale
Enclosure Class : IP-65 or better (Explosion/Flame proof for NEC
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METUR THERMAL POWER STATION-I (4X210MW)
Test wells shall be provided on main steam, reheat steam, spray water lines and other
piping as required to meet ASME test requirements.
1. Radar type level Instrumentation shall be used when the physical properties of the
medium between the sensor and measured interface may vary.
2. The Radar type level Instrument shall be microprocessor based with HART protocol and
shall use digital signal processing techniques for signal conditioning and shall be
possible to calibrate through universal HART calibrator.
3. Radar type level transmitter shall have facilities for storing echo profile, manipulation of
the echo profile to remove noise, multiple profile-averaging etc.
4. Chemical compatibility of the sensor material with the process material shall be ensured
to avoid corrosion.
5. The sensor shall have in-built temperature sensor for ambient temperature compensation.
6. Necessary software, cables, connectors, HART to RS 232C converters etc shall be
provided.
7. Suitable protection box for mounting radar type level transmitters shall be provided for
mechanical protection & dust. Swiveling arrangement shall be provided for proper
aiming / focusing of radar type level transmitters.
1. Level gauges shall be steel armoured reflex or transparent or bi – colour type, top and
bottom connection as per pressure vessel standard of ASME PTC code and 15 mm NB
(1/2 inch NPT) Drain and vent connection.
2. Body material and cover material shall normally be forged carbon steel, 304 stainless
steel or other superior material.
3. Reflex type gauges shall be used for clean and colorless liquids and transparent type for
other liquids. For boiler and condensate services, treated water, the transparent type with
KEL – F shields shall be used to avoid their attack on the glands.
4. The gauge glass must have a rating equal to or more than the vessel design pressure and
temperature. The test pressure for the complete design gauge assembly shall be as per
Owner’ / Consultant’s recommendation.
5. The maximum length of a single gauge glass shall not exceed 1.4 meters. Where large
range is required, multiple gauges of preferably equal lengths shall be used with 50 mm
over – lapping in visibility.
6. The visibility shall cover the operating level range and the maximum and minimum
ranges expected considering start – up conditions as well as alarm and shut down points.
Internal heating shall be provided for viscous liquids. Integral illuminators shall be used
for transparent gauges, if necessary.
7. Stand – pipes,shall be used for multi – gauge and level controller installation and on
horizontal drum or exchanger with top and bottom connections to have visibility of the
complete span. The standpipe shall not be used with block valves.
8. Primary isolation valves shall be used in addition to the gauge glass valves unless
otherwise specified. When the process fluid may create plugging or leakage problem,
gauge valves may be omitted. For low temperature liquid having high vapour pressure at
ambient temperature, isolation and gauge valves shall not be permissible. Safety valve
shall be provided at the vent connection of the gauge glass where isolation is required.
9. Level gauge shall be supplied as per the following specification:
- Temperature equalizing column expansion bend and chain patterned hand – wheel
- Certification by Inspectorate of Boiler (If applicable)
A. INTRODUCTION
1. The control valves and accessories equipment furnished by the biddershall be designed,
constructed and tested in accordance with the latest applicable requirements of codefor
pressure piping ANSI B 31.1, the ASME Boiler & Pressure Vessel code, Indian Boiler
Regulation (IBR) & ISA as well as in accordance with applicable requirements of the
“Federal Occupational safety and Health Standards, USA” or acceptable equal standards.
1. The design of all valve bodies shall meet the specification requirements and shall
conform o the requirements of ANSI for dimensions, material thickness and material
specification for their respective pressure classes.
2. The valve sizing shall be suitable for obtaining maximum flow conditions with valve
opening at approximately 80% of total valve stem travel and minimum flow conditions
with valve stem travel not less than 20% of total valve travel. All the valves shall be
capable of handling at least 120% of the required maximum flow. Further, the valve
stem travel range from minimum flow condition to maximum flow condition shall not be
less than 50% of the total valve stem travel. The sizing shall be in accordance with the
latest edition of ISA Handbook on control valves, While deciding the size of valves,
bidder shall ensure that valves outlet velocity does not exceed 8 m / sec. for liquid
services 150 m/sec. for steam services and 50% of sonic velocity for flashing services.
Bidder shall furnish the sizing calculations clearly indicating the outlet velocity achieved
with the valve size selected by him as well as noise calculations, which shall be subject
to consultation’s / owner’s approval during detailed engineering.
3. Control valves for steam and water applications shall be designed to prevent cavitations,
wire drawing, flashing on the downstream side of valve and down stream piping. Thus
for cavitations / flashing service, only valve with anti-cavitations trim shall be provided.
Detailed calculations to establish whether cavitations shall occur or not for any given
application shall be furnished.
4. Trim shall be multistage type having sufficient number of discrete pressure drop turns
(stages) to ensure elimination of vibration, erosive – action, cavitations. Bidder shall
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METUR THERMAL POWER STATION-I (4X210MW)
identity the number of pressure drop turns in proposed equipment and shall also provide
calculation demonstrating compliance to the trim exit velocity.
5. To prevent flow induced vibration and to protect the valve intervals from foreign
particles such as weld slag flow, direction shall be a flow to close (over the plug)
configuration for liquid applications. To maximize noise attenuating benefits and to
allow for constant fluid expansion, flow direction shall be under the plug for steam and
gas applications.
6. The control valve induced noise shall be limited to 85 dBA at 1 meter from the valve
surface under actual operating conditions. The noise abatement shall be achieved by
valve body and trim design and not by use of silencers.
7. The characteristic of the control valves shall be determined based on the application /
service.
8. On supply air or electrical failure for pneumatic/ electrical drive, the valve shall remain
full closed, open or stay – put position as per process safety requirement.
C. VALVE CONSTRUCTION
D. VALVE MATERIALS
(i) Carbon steel as per ASTM – A216 GR WCB for non – corrosive, non – flashing and
non – cavitations services below 275 0C temperature above 275 deg C ASTM-A217 GR
WC 9
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METUR THERMAL POWER STATION-I (4X210MW)
(ii) Alloy steel as per ASTM – A217 GR WC 9 for severe flashing / cavitations services like
low load and full load feed water control, Heaters emergency drains, etc.
(iii) Alloy steel as per ASTM A – 217 GR WC 6 for low flashing / cavitations services like
Heaters normal drain control, drain cooler normal level control, gland steam cooler
minimum flow etc.
(iv) 316 SS for condensate service below 300 0C like condensate normal and emergency
make – up controls etc.
(i) 17 – 4 PH SS for severe services listed under item D1,(i) ii) &(iii) above
(ii) SS 440-C for severe services listed under item D1 (iv) above
(iii) 316 SS for services listed at D.1 (iv) above and
(iv) 316 SS with stellite faced guide parts and bushings for remaining applications.
3. However, Bidder may offer valves with body and trim materials better than specified
materials and in such cases vender shall furnish the comparison of properties including
cavitations resistance, hardness, tensile, strength, strain, energy, corrosion resistance and
erosion resistance etc of the offered material vis – a – vis the specified material for
Consultant’s / Owner’s consideration and approval.
E. END PREPARATION
1. valve body ends shall be either butt welded / socket welded, flanged or screwed as
finalized during detailed engineering and as per Consultant’s / Owner’s approval. The
welded ends wherever required shall be butt welded type as per ANSI B 16.25 for
control valves of sizes 65 mm and above. For valves sizes 50 mm and below welded
ends shall be socket welded as per ANSI B 16.11. Flanged ends wherever required shall
be of ANSI pressure – temperature class equal to or greater than of the control valve
body.
F. VALVE ACTUATOR
1. All regulating control valves shall be furnished with pneumatic actuators . For
pneumatic actuators, compressed instrument air shall be used and for this, necessary
provision of Pressure Reducing Station (PRS) shall be considered. The bidder shall be
responsible for proper selection and sizing of valve actuators in accordance with the
pressure drop and maximum shut off pressure and leakage class requirements. The valve
actuators shall be capable of operating at 600c continuously.
2. Valve actuators and stems shall be adequate to handle the unbalanced forces occurring
under the specified flow conditions or the maximum differential pressure specified. An
adequate allowance for stem force, at least 0.15 kg / cm2 per linear millimeter of seating
surface, shall be provided in the selection of the actuator to ensure tight seating unless
otherwise specified.
4. For quick opening / closing services the actuator shall be pilot solenoid operated
pneumatic drive, the rating of solenoid shall be 24V DC or 110 V AC shall be decided
during detail engineering. (If applicable)
5. Selection of actuator shall be such that it meets the requirements of thrust / torque, stroke
length, angular movement, full scale travel time, repeatability & accurate positioning for
successful operation of final control element.
6. All the actuators shall have also provision for manual operation during emergency /
maintenance along with graduated local position indicator.
1. All control valve accessories such as self reset type air lock valves with tubing, hand
wheels / hand jacks, SMART positioners, solenoid valves, volume booster, air filter &
regulator, diffusers, external volume chambers, position transmitters (capacitance or
resistance type only), tubing, fittings and junction boxers etc. shall be provided as per
the requirements.
1. SMART positioner shall preferably be of the same make as the Control Valve, toensure
repeatability in Calibration, serviceability and proper maintenance of the Control
System.
2. SMART positioner shall be a Double stage positioner. The first stage of the positioned
shall be typically a flapper-nozzle that serves as a high-gain pre-amplifier. This
sensitivity shall be maintained over a wide range of dynamic conditions. Second stage
shall be a power amplifier that provides power to drive the actuator. Preferably this shall
be a pneumatic relay. Spool Driven type SMART positioners are not preferred due to
Higher Dead Band and Poor responsiveness. The SMART positioner shall have pressure
sensors to measure the pneumatic outputs to the actuator.
3. The control algorithm for the positioner shall use feedback signal from the motion of the
pneumatic relay beam instead of pressure feedback to minimize pneumatic related
effects and for stable and smooth response of the control valve. The SMART positioned
shall have user adjustable tuning sets to identify the optimum tuning for the total valve
assembly. SMART Positioner with HART Communication facility shall communicate
all the valve diagnostics to Plant DCS.
1. All valves shall be tested in accordance with the quality assurance plan agreed between
the Owner / consultant and the vender which shall meet the requirement of applicable
codes.
I GENERAL REQUIREMENTS
1. Bidder shall furnish all the control valves as finalized during detailed engineering stage
without any price repercussions whatsoever depending on the process requirements
including the system under.
2. Following documents to be furnished by the bidder after the award of contract.
i) Control valves shall be furnished with applicable certification for FGD plant, wherever
required.
1. Noise: The maximum allowable noise level shall be 85 dbA or less at 1 m. distance from
the downstream bare pipe surface. The specified noise level shall be attained without
the use of orifices, mufflers, diffusers. No credit for thermal or acoustical insulations
shall be taken.
2. Valve Trim: Valve shall have quick change type trim utilizing top entry. No
components shall be screwed or welded into the body. The valve shall have equal
pressure distribution around the plug to avoid chattering / vibration.
Trim of severe/critical service valve shall be of multi stage & multi path design with
sufficient no. of discrete pressure drop stage to eliminate the chance of erosion,
cavitations, noise, vibration through out the control range of valve.
3. Leakage Class: The valve shall have minimum leakage class as per process application
4. The valve trim should be multistage, multipath design having sufficient numbers of
discrete pressure reductions (turns/stages) to ensure elimination of vibration, capitations,
erosion and noise effects.
5. Bidder should work out number of pressure drop turns in the trim of the valve and
should provide calculations of trim exit velocity.
6. Flow Vs. valve opening characteristics: the trim is to be so designed that the minimum
flow indicated in the bid specifications of the valve is achieved with minimum lift of
8mm. of valve plug from ‘close’ position. Subsequent characteristics should be ‘Equal
Percentage’ i.e. corresponding to the parabolic characteristics. Characterizing the cam of
the positioner to mimic the required flow characteristics is not acceptable.
8. Each pressure reducing element should have a uniform pressure distribution around the
plug to avoid mechanical vibrations(pressure equalizing rings/ grooves).
9. To prevent flow induced vibrations and the line trace damage to seat, the flow direction
should be over the plug for water and under the plug for steam.
10. During throttle opening of the control valve, flow should be diverted away from the
body seat.
12. Leakage class for all the control valves required valves required is MSS-SP-61 better
than ANSI / FCI-70.2class-V or equivalent as the control valves are to work as block
valves when in `CLOSE” condition. The bidder should indicate how this will be
achieved in their valves and actuators.
13. Bidder to indicate the closing force on the seat in kgf/mm of seat circumference applied
for actuator.
14. Trim exit velocity in both minimum and maximum flow conditions should be less than
30M/Sec. in case of water and 22.5M/sec in case of flashing water conditions.
Calculation sheet should be attached demonstrating satisfactory compliance of this
requirement.
15. Noise level at 1 meter distance from the valve should be less than 85dB without
insulation, Orifices, silencers mufflers etc. Calculation sheet to be attached for each
valve offered.
16. Critical cavitations index (Kc) for all control valves should be approximately 10 (> 9.9).
This is specific requirement to avoid even remote possibility of cavitational damage to
valve internals.
17. To avoid problems associated with the piston rings provided in valves of balanced
design, unbalanced design for port size upto 25mm. is required. Bidder to indicate the
compliance clearly.
20. Accessories:
Control valve actuators shall be equipped with air supply filter regulator, gauges and
valve positioners along with boosters for typical applications wherever required, local
poison indicator with scale and pointer, position transmitter, limit switch and hand
wheel, air lock relay, solenoid valve etc.
The primary element shall have a flanged metallic tube with a non-conductive liner. The
tube liner material shall be PTFE or compatible with the process fluid. Liner shall be
extended over the full width of the flange face to the bolt circle. Liner thickness shall be
selected to suit the application.
Electrode material / shred material shall be best suited to the fluid, to minimize
corrosion or abrasive wear. Electrode shall be of self-cleaning type. Recessed electrode
faces are not acceptable.
The coils house shall be completely coated with an epoxy material and shall be rigid and
impervious to total immersion in water. Leads shall be adequately supported.
The transmitter shall be SMART, 4…20mA isolated output with integral LCD display
and HART protocol. Required cable between sensor and transmitter shall be provided
for remote type transmitter. The cable entry to the transmitter shall be ½” NPT. The
power supply to the transmitter shall be 240V AC and the transmitter shall power the
sensors. The transmitter housing shall be of die-cast aluminum.
The accuracy of the system shall be ±0.2% of FSD. System accuracy shall not be
affected by changes in process medium concentration, density, or particle size
distribution. The system shall be suited for outdoor installation and shall have IP65 or
better enclosure. The calibration range shall be easily changed without removal of the
flow meter from the process.
The meter shall be capable of attenuating noise induced by solids in the slurry bouncing
against the meter electrodes. For potential equalization, grounding rings shall be
provided. The calibration range shall be easily changed without removal of the flow
meter from the process. Straight length requirement shall be as specified by
manufacturer. If meter size is smaller than the line size, concentric pipe reducers shall be
used. Eccentric reducers shall not be used as they disturb the flow profile.
01.05.14 Rotameter
Rotameter shall be provided with following features:
Material
- For On-line type
Metering Tube Borosilicate glass
Float 316 SS
Packing Teflon
End fittings 304 SS
-For Bypass type
Metering Tube Borosilicate glass
Float 316 SS
Packing Teflon
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METUR THERMAL POWER STATION-I (4X210MW)
Flapper type.
Materials
Body Carbon steel/SS316 as per process
requirement
Glass Toughened Borosilicate
Gaskets Neoprene
Bolts & nuts SS
Flappers / Rotating Wheel 316 SS
Flappers / Rotating Wheel holder 304 SS
Process Connection SW (Socket Welded)
Accessories Scale, Bolts, Nuts, Cover plates and
Gaskets as required
Tests Tested at two hundred (200) percent of
the maximum process pressure.
Accessories Counter flange, Cable gland, prefab cable and stainless steel
name plate engraved with alpha-numeric.
- Float/Displacer 316 SS
- Wire rope 316 SS
Differential + 12 mm minimum (Adjustable)
Contacts
- Number DPDT/2 SPDT
- Type Snap action micro switch with silver vetted
- Rating 5 Amp 240V AC, 0.2 Amp 220V DC
Connection
- Process One (1) inch SCRD NPT Female Or One (1) inch ANSI
Flanged
Four(4) inch ANSI Flange for sump services
Electrical Suitable for gland 3/4 inch
Temperature/pressure As per service conditions
rating
Accessories Counter flanges, still pipe of requisite length with
anticorrosive coating for sump services.
Repeatability : 100%
Sensing Probe
Transmitter
Mounting : On Nozzle
Mounting position : Top mounted
Housing : Plastic
Display : Head mounted LCD Display and remote display
Accessories : As per process requirement
Process connection : NPT/Flanged
Electrical connection : 1/4” NPT
Turn Down ratio : 1:25
Measuring range : Adjustable (as per process requirement)
Totaliser : Required
No. of contact : 2 NO + 2 NC
Solenoid valves shall be provided with control valves / pneumatic control valves hooked
up with process interlock requirements and where direct tripping is involved. The
number of ways for solenoid valve shall be provided as indicated below:
(a) Two (2) way solenoid valves shall be provided, where process line of less than 50 mm
with low pressure and temperature application.
(b) Three (3) way solenoid valve shall be provided commonly, where the pressure is
admitted or exhausted from a diaphragm valve or single acting cylinder, e.g, Pneumatic
operated spray water block valve.
(c) Four (4) way solenoid valve shall be provided for operating double acting cylinders, e.g,
Pneumatically operated on-off type dampers.
(d) Solenoid Valve coils shall be Class-H high-temperature or Class-F construction as
applicable and shall be designed for continuous duty. Three-way solenoid valves shall be
designed for universal operation so that the supply air may be connected to any port.
Solenoid enclosures shall be NEMA-4.
(e) All solenoid shall be with varister, LED indication, surge suppress diodeand circuits.
Control Signal 0.2 to 1 Kg/Sq. cm. from I/P converter for modulating
purposes. 24Voperated solenoid valve operating on
pneumatic line. The Pilot solenoid will have separate
coils for open closing purpose.
Supply Air 0-7 Kg / Cm2.
Selection Based upon thrust / torque, stroke length, angular
movement, full-scale travel time, repeatability,
space factor etc. Provision for air-to-open and
air-to-close operation.
Casing IP-65.
Accessories (as required) a) Air lock relay
b) Hand wheel.
c) Air filter regulator with gauge.
d) Volume Booster.
e) Limit Switches (non-contact type).
f) Positioner with Input, Output and supply
pressure gauges.
g) Pilot Solenoid Valve (Double Coil type)
h) Position Transmitter (4-20 mA DC linear
output, LVDT or non contact type).
Fail-safe operation Stay put, open or close position on pneumatic
/electrical power supply failure as per process
safety criteria.
Repeatability Better than 0.5% of full travel.
Hysterisis Less than 1% of full travel.
Rear panel , roof plate & 1.5mm SS sheet with foamed –in seal
bottom plate
Mounting plate To be provided
Gland Plate 3 mm flush type gland plate
Cable entry Bottom or Side
Cable glands Double compression type – Nickel plated brass with
PVC hoods.
Mounting Indoor/Outdoor
No. of terminals As required with standardization with 20% spare of
each size & type.
Terminals screw less cage clamp type
Grounding Two terminals for body and shield ground
Door Hinged, lockable type (IP type lock) with common
key
1 General Requirements
The design, material, construction features, manufacture, inspection and testing of flow
elements shall comply with all currently applicable statutes, regulations and safety
codes in the locality where the equipment will be installed. The equipment shall also
conform to the latest applicable standards. Nothing in this specification shall be
construed to relieve the Bidder of this responsibility.
2 Technical Requirement
316SS long radius, weld in flow nozzles with D and D/2 pressure tapings; 316SS flow
orifice plate assembly with flange tap connections; Beta ratio of 0.6 to 0.7.Element
material of SS 316. The material of Flow nozzle shall be A182F91, where pipe material
is A335P91. The material of all type of accessories will be SS316. End connections for
flow elements will be butt welded except orifice plate on condensate return line to CST,
which will be flanged. The accuracy of the flow element shall be + 0.5% or better.
There shall be four(4) pairs of tapings, out of which three(3) pairs shall be used for
mounting of DP type flow transmitters for control & monitoring whereas the fourth pair
shall be used during performance guarantee test by of plant by Bidder.
Standards
The flow elements (Orifice plates) shall be designed in accordance with ASME PTC –
19.5 (Pt – II), ISA RP3.2or BS 1042/ISO 5167.
The flow elements (Flow Nozzles and Aerofoil/Venturi Nozzles) shall be designed in
accordance with ASME PTC – 19.5 (Pt – II), or BS 1042/ISO 5167.
Construction and installation of flow nozzles and orifices shall conform to the
requirements of ASME Performance Test Code PTC-19.5 as mentioned above and dis-
charge coefficients shall be predicted in accordance with data published in ASME
Research Report on Fluid Meters.
3 Orifice Plate
Concentric orifice plates shall only be provided for other flow measurements where
flanged construction and higher pressure losses are acceptable. Orifice plates shall be
made of SS316. The standard primary element shall be thin plate, square-edge
concentric. Orifice flanges shall be of the raised face weld neck type with dual sets of taps.
The minimum pressure rating for flanges shall be ANSI 300lbs. Thickness of Orifice plate
shall be 3 mm (minimum) for pipe diameter up to 300 mm and 6 mm (minimum) for pipe
diameter above 300 mm. Orifice plates shall be supplied with carrier rings as per process
requirements.
The length of straight pipe run required for metering accuracy shall be in conformity
with ISO. When it is extremely difficult to comply with the standard, a minimum
straight length of 1OD (D = pipe inner diameter) on the upper stream and a minimum
length of 5D on the down stream shall be considered
For pipeline sizes of 500 mm and less, the orifice plates shall be an integral unit
comprising of carrier ring assembly, tapping arrangement on both upstream as well
down stream side. For line sizes more than 500 mm, the orifice plate shall be disc type.
For disc type orifice plate, suitable corner tapping arrangement on both upstream as well
as downstream side shall be provided. All tapping arrangements shall be complete with
a piece of impulse pipe line and a shut – off valve suitable for specified line pressure
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METUR THERMAL POWER STATION-I (4X210MW)
For steam applications, orifice plate shall be supplied with a pair of steam condensation
chambers suitable for specified line pressure.
Feature Minimum Requirement
Concentric as per ASME PTC – 19.5 (Part III); ISA
Type
RP – 3.2; BS – 1042; ISO 5167
Material SS 316
3 mm for main pipe diameter up to 300 mm and 6
Thickness
mm for main pipe dia above 300 mm.
Beta ratio 0.4 to 0.7
Tapping Flanged weld neck 3 pairs of tappings.
Material of Branch Pipe SS 316
Root Valve type Globe
Root Valve material SS 316
Root Valve size 1” or ½ “
Accessories Root valves, flanges, vent / drain hole (as required)
1. Bidder to provide Beta ratio calculation, Assembly drawings & flow vs DP curves.
2. Each orifice plate shall be provided with a handle on which the orifice diameter, pipe
diameter and pressure tap distances are stamped. This information shall be so located that
it can be read without removing the orifice plate from pipe line.
3. Quadrant edge or quarter circle orifice plates shall be used for highly viscous liquids and
for pipe Reynolds Number below 10,000. Conical entrance type of orifice plates shall
preferably be used for very highly viscous liquids up to Reynolds Number below 250.
Vent and drain holes shall be provided wherever necessary.
4. Orifice diameter shall be selected, so that d/D ratio is between 0.40 to 0.70 for gas and
steam and up to 0.75 for liquids.
5. Restriction orifices and integral orifice transmitters do not require upstream or
downstream straight pipe runs.
6. The orifice plate shall be supplied and fitted in conformity with ISO. When the pipe
diameter is larger than the value specified in ISO, the restriction ratio will be decided by
extending the specific curve externally.
7. Performance
The Bidder shall submit type test certificate from a recognized test house
certifying evaluation of construction standard, accuracy of calibration.
Wet calibration shall be carried out as on each size and design of flow element as per
ASME PTC or BS 1042/ISO 5167. The other tests shall conform to ASME-PTC 19.5.
The Biddershall submit the reports for all the tests carried out for Purchaser's review and
records. The functional test shall also be witnessed by customer as per approved
document.
I. GENERAL
I.01 Bidder shall familiarize with the permit requirement of the plant and supply a
Continuous Emission Monitoring System complete in all respects to meet the
environmental monitoring requirements.
II.01 Flue gas analyzers shall be provided for FGD stack continuous emission monitoring
system (CEMS). Stack emission monitoring system shall comprise of CO, CO2, SOx,
NOx, O2 Analyzer, Dust / Opacity Analyzer, Stack Gas Flow, Pressure, Temperature and
Mercury Analyzer.
II.02 In addition to continuous environment monitoring system, manual sampling provision for
flue gas monitoring should be provided as per Emission latest Regulation of
CPCB/TNPCB in each stack along with necessary provision of platform, lighting facility,
safety rails and ladders etc. complete in all respect.
II.03 Type, quantity and locations of tapings in stack shall strictly follow the norms as
stipulated by the latest norms of MOEF / Central Pollution Control Board/ TNPCB. The
measurement shall also conform to EPA, TUV, MCERTS or equivalents regulations.
II.04 A dedicated Operating Station with calculations software, application software, report
generation software packages, diagnostics and data logging features & B/W A4 sized LJP
and Laptop for site calibration shall be provided along with the furniture for each unit.
Remote calibration of all analyzers shall be provided.
II.05 Hardwired & soft signal exchange shall be envisaged between FGD PLCs & CEMS.
Provision shall be available at separate terminal block in CEMS cabinets for Hardware
interface of analyser signals for CPCB/ TNPCB interface.
II.06 Power supply to CEMS shall be from FGD Unit /Dedicated UPS. The bidder shall lay
necessary cable from ACDB in CER/CEMS room to CEMS Panel.
II.07 A permanent environmentally controlled (air-conditioned) room for each CEMS system,
with suitable electrification shall be provided to house all non-on-line mounted
components including calibration gases in the vicinity of the sampling location. Proposed
location of CEMS Room is zero mtrs. Elevation near stack.
III.02 All output signals of all stack monitoring analyzers shall be hardwired and connected to
FGD PLC system as applicable for monitoring, archiving and report generation for
environmental monitoring authorities.
CEMS OWS shall be equipped/ loaded with necessary Stack emission monitoring
system’s calculations and report generation software packages for generation of report for
submission to environmental monitoring authorities. This is specific application software,
shall be supplied by CEMS vendor.
Each Analyzer shall be provided with RS485 output required to connect with CEMS
operating work station, and port for calibration from Laptop.
Output of CO/ SOx/ NOx/ CO2/O2/ Dust monitors/ Stack flow analyzers shall be
normalized for temperature, pressure, water, vapour etc. This facility should be available
in respective gas analyzer.
Weather protection against direct sun light, rain etc. for flow meter, local display / local
indicators shall be provided by Bidder.
Heated sampling line of PTFE material shall be provided from sampling point to panel
for measurement. Sample line shall be electrically heat traced. Power supply for heat
tracing tube shall be from UPS.
The common requirements to be met for all types of analyzers are as below. The specific
requirements to be met by each type of analyzer are detailed in the subsequent clauses.
1. Output Signals
Adjustment
3. Ambient temp. 50 °C
UPS
Standards standards
III.05 A data logger system shall be provided for acquiring the CEMS data from the analyses
and for transmitting the same to FGD PLC & CEMS OWS. A programmable controller
shall be provided for signal output, alarms, calibration cycle timers and measurement
indication for each analyzer. The controller shall be panel or rack mounted and furnished
with interconnecting cable to the field-mounted analyzer. Calibration cycle time shall be
set over fixed internals and sequenced by the controller.
III.06 CEMS OWS station with application software shall be provided for the system.
Application software shall have the following minimum capabilities:
All the data shall also be available on FGD PLC for analysis and monitoring from CEMS
OWS through redundant Bus (Modbus RTU or Modbus TCP/IP or OPC for soft link
interfacing). Interfaces shall be over optical fiber cable or Ethernet STP cables and shall
be decided during detail engineering stage based on Supplier’s standard practice
considering any distance limitation. Interfacing with FGD PLC shall be provided by
Bidder. Workstation end hardware including LIUs, Modems etc. as required establishing
the connectivity with CPCB shall be also provided by Bidder.
Recording / To be provided
Totalizing/Logging
CONTROL & INSTRUMENTATION SYSTEM Page 65 of 119
© 2020 MECON Limited. All rights reserved.
TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METUR THERMAL POWER STATION-I (4X210MW)
viii) Inner sheath shall be Extruded HRPVC (ST2 type) / FRLS (as applicable)/ LSZH (as
applicable). Thickness (nom) shall be as per latest Indian standard. Inner sheath colour
shall be black.
ix) Overall shielding shall be helical type 0.075 mm thick aluminum Mylar tape with 100%
coverage and 25% overlapping.
x) Overall drain wire shall be of annealed tinned copper, 0.5 mm2, and 7 strands
continuously in contact with the shield.
xi) Ripcord shall be provided & shall be non-metallic type under sheath.
xii) Armour material shall be galvanized round steel wire.
xiii) Armour size shall be as per latest Indian standard.
xiv) Outer sheath shall be Extruded HRPVC (ST2 type) / FRLS (as applicable)/ LSZH (as
applicable). Thickness (nom) shall be as per as per latest Indian standard. Outer sheath
colour shall be blue.
xv) Tests shall be carried out according to following standards of latest revision:
a) General: IS: 1554 (Part I) except for thick nesses of insulation & sheath.
b) Insulation: IS: 5831except insulation resistance, Voltage and Spark tests,
which shall be as per BS 5308 Part II
c) Armour: IS: 3975
d) Armour Galvanisation: IS: 2633
e) FRLS properties test
• Oxygen Index According to: ASTM D2863
• Temperature Index According to ASTM D2863
• HCl Emission According to IEC 754-1
• Smoke density According to ASTM D2843
• Flame Retardant test According to IEC-332 Part III Cat A
xvi) Pair/ Triad shall be identified with numbers as per BS 5308. IEC 60092-376
xvii) Electrical characteristics, values like, resistance at 20 0C, Mutual capacitance (core to
core), mutual capacitance (core to screen), mutual inductance, L/R ratio shall be
indicated in the specification datasheets.
xviii) A durable marking provided on the surface of the cable at regular intervals not
exceeding 625 mm. The marking shall include manufacturer’s name, conductor
material and size, no. of pair, insulating material etc. as per IS: 1554 (Part I).
ii) Conductor material shall be annealed, tinned, multi-stranded electrolytic copper of 1.5
mm2.
iii) Number of strands and strand size shall be min 7/0.53.
iv) Primary insulation material shall be of Extruded HRPVC type C. Thickness (nom) shall
be 0.8 mm.
v) Inner sheath shall be Extruded HRPVC (ST2 type) / FRLS (as applicable)/ LSZH (as
applicable). Thickness (nom) shall be 0.3mm. Inner sheath colour shall be black.
vi) Armouring shall be of galvanized round steel wire or galvanized steel strip as per IS
1554 (Part 1).
vii) Outer sheath shall be Extruded HRPVC (ST2 type) / FRLS (as applicable)/ LSZH (as
applicable). Thickness (nom) shall be 1.24 mm, 1.4 mm, 1.56 mm as applicable &
conforming to IS 1554. Outer sheath colour shall be black.
viii) Tests shall be carried out according to following standards of latest revision:
a) General: IS: 1554 (Part I).
b) Insulation: IS: 5831
c) Armour: IS: 3975
d) ArmourGalvanisation: IS: 2633
e) FRLS properties test
• Oxygen Index According to: ASTM D2863
• Temperature Index According to ASTM D2863
• HCl Emission According to IEC 754-1
• Smoke density According to ASTM D2843
• Flame Retardant test According to IEC-332 Part III Cat A
3. Shield shall be kept open at the instrument end and to be connected to the electronic
earth pit at the control room end.
4. For shielded compensating cable the shield shall be earthed near the point of the circuit
ground. For grounded junction thermocouples, this means at the thermocouple head.
For ungrounded junction thermocouples this means at the control room end.
b. Type
c. Material:
i) Number 2SPDT
j. Mounting
k. Connection:
v) Standard pH solutions
1. Accelerometer type 4-20mA 2- wire Vibration monitoring sensor will be provided for
all HT drive pumps & motors signals which will be connected to PLC.
3. VMS will have necessary interfacing give output of 4-20 mA DC for each point
monitored. The signal will be suitable for use as an input to PLC as well as for trending
linear in proportion to vibration velocity as well as displacement.
e. The above items are indicative only. Over and above any items & accessories, if
required, for completeness of vibration monitoring system shall be supplied,
even if it is not specifically indicated in this specification.
2. Output 4-20mA
7. Display Yes
01.05.38 Servers/Workstations/printers
4. Monitor Min 24” LED Flat Monitor Min 24” LED Flat Monitor
(color) with resolution of 1920 x with resolution of 1920 x
1080 non-interfaced refresh 1080 non-interfaced refresh
rate min. 75 Hz. rate min. 75 Hz.
For NMS server, the dual CPU speed shall be 3.0 GHz or more, RAM shall be 8 GB or
more and the hard disk space shall be 500 GB or more.
The supervisory function of HMI like log, calculations, shall be implemented in
redundant Server/Information workstation, so that no functions are lost due to a signal
failure.
The mouse/keyboard/monitor shall have extra length of cable depending on the location
of CPU
Printers
Colour Laser
Sl no. Features B&W Laser Printer (A4)
Printer (A3)
Colour Laser
Sl no. Features B&W Laser Printer (A4)
Printer (A3)
One intelligent SNMP manageable mini-UPS for 30 minutes backup shall be provided
with all accessories and software.
01.05.40 Firewall:
The firewall must send log information to a separate log server via an encrypted
connection. Firewall logging must not impact firewall performance.
Remote network access to the firewall should only be possible through the
administration interface.
The firewall must not support any unencrypted means of access to the firewall.
It should Monitor ALL network traffic-traffic at Firewalls (Internet and external
networks), in the DMZ and detect known threat through deep packet inspection.
Detect unknown threats via anomaly scanning.
Detect unknown threats via behavior pattern to protect from zero day attacks.
Keep up-to-date on new threats and vulnerabilities.
Co-axial cables are used for high frequency equipment and systems for transmission
and reception purposes and computers. Co-axial cable should have minimum following
characteristics:-
1.1 This specification describes the minimum general requirements for the design,
manufacture, supply, inspection, installation, testing & commissioning of optical fibre
cable & accessories.
1.2. Bidder shall consider all related activities such as cable stripping, Cable entry in boxes
& panels, cable fibre splicing/fusion, cable performance testing & other services, to
achieve properly documented & operational cable network.
1.3. OFC shall be installed on cable tray, duct bank, cable trench installation as necessary.
For outdoor applications the cable shall be armoured with Poly Ethylene sheathing. In
all cases cable shall be routed through suitable grade HDPE permanently lubricated
protection pipe as per IS-4984, IS-12235 & TEC.G/CDS-08/01 of suitable size @ 53%
fill factor.
1.4. Fiber Optic cables shall be suitable for installation on cable tray, duct bank, cable
trench, racks and direct burial as necessary. Spliced / repaired cables are not acceptable.
1.5. Bidder to ensure that minimum 100% cores are kept as spares in all types of fiber optic
cables.
1.6 Fibre Optic Cables shall be separate for each service, Package, etc. and two (2) or more
services shall not be clubbed i.e. F O Cables for DCS signals, Video signals, any other
signals of CCTV shall not be through the same cable.
2.1 Fiber The optical fiber core shall be of ultra pure fused silica
glass coated with UV-cured acrylate suitable to
withstand temperature of about 80 Deg C continuously
2.17 Fiber Proof test As per IEC/EIA & other international standard.
2.21 Core wrapping / Water Swellable Tape / Suitable Water Blocking Gel
Moisture barrier
3.3 Buffer Tubes Shall be stranded around the central member utilizing
reverse oscillating lay (ROL)
3.7 Outer Jacket High density Polyethylene (HDPE) minimum 1.5 mm thick,
Flame retardant & UV resistant
3.10 Ripcord Two highly visible ripcords shall be placed under the jacket
/ armour for easy outer jacket / sheath removal.
4.2 Life Fiber Optic cable shall provide a long life expectancy of
Expectancy minimum 25 years under continuous operation without
degradation to optical or mechanical performance.
4.4 Storage - 20 0 C to 60 0 C
Temperature
4.5 Operating - 20 0 C to 70 0 C
Temperature
(IEC 60794-1-
2-E1)
5.3 Method of Directly laid in cable trays / duct bank / clamped with
laying available structure
Strength
v) Rodent resistant
Bidder shall provide 1 no. new unused Fiber optic splicer terminator tool kit with box
comprising of splicer and fusion jointer and tool kit shall comprise of cutter, stripper,
polishing tool, handheld microscope, heat shrinkable sleeve, scissor, knife etc as
required for maintenance and commissioning.
Conductor
Insulation :
Thickness : 0.254 mm -
Binder Tape :
Thickness :
Stranded (7/32) , 24
Thickness :
AWG
Outer Jacket
Mechanical
Characteristics
(Overall)
Installation Temperature
: -25 to +75 Deg.C -25 to +75 Deg.C
Range:
Operating Temperature
: -40 to +75 Deg.C -40 to +75 Deg.C
Range:
Tensile strength :
Max. Recommended
: 177.928 N 200.169 N
Pulling Tension
Min. Bend/Installation :
NEC/(UL)
: CMR CMR
Specification
Electrical
Characteristics
Nominal Mutual
: 49.215 pF/m 50.8555 pF/m
Capacitance
Nominal Velocity of
: 70% 67%
Propagation (VP)
Max. Conductor DC
: 9.38 Ohm/100m 8.2 Ohm/100m
Resistance @ 20deg. C
Impedance :
Attenuation min. At
: 22 dB at 100 Mhz 18.9 dB at 100 Mhz
100m
EU Directive
EU Directive
2011/65/EU(RoHSII),
Applicable standards : 2011/65/EU(RoHSII), MII
MII Order # 39 (China
Order # 39 (China RoHS)
RoHS)
Test
01.05.45 NOTE: All cables near high temperature zone shall be high temp cables, which shall be
terminated at a junction box in normal temperature zone. Thermocouple extension
cables and copper conductor cables for high temperature applications shall be with
insulation of individual conductor and outer sheath of extruded FEP (i.e. Teflon) as per
VDE 0207 Part 6 and ASTMD 2116. The thickness of insulation shall be 0.5 mm
nominal (i.e. 0.4 mm minimum). These cables shall be single / Multipair twisted &
shielded.
3 Material Brass
1. Conduits shall be generally used for interconnecting cables from field instruments to
Local JBs. All unarmoured cables shall be installed in conduit. All rigid conduits,
couplings and elbows shall be hot dipped galvanized rigid mild steel in accordance with
IS: 9537 Part-I (1980) and Part-II (1981). The conduit interior and exterior surfaces
shall have continuous zinc coating with an overcoat of transparent enamel lacquer or
zinc chromate. Flexible metal conduit shall be heat resistant lead coated steel, water
leak, fire and rust proof. The temperature rating of flexible conduit shall be suitable for
actual applications. The flexible metal conduit shall be constructed with an interlocked
corrosion resistant steel & manufactured in accordance with UL1 & NEC Article 348.
2. The Bidder shall install conduits according to the general routing as approved by
Purchaser / Consultant and shall coordinate conduit locations with other works.
3. All grounding bushings within all enclosures shall be wired together and connected
internally to the enclosure grounding lug or grounding bus with 8 AWG bare copper
conductors. Conduit runs to individually mounted equipment shall be grounded to
the Purchaser’s cable tray grounding conductor with 12 AWG bare copper
conductors. All grounding bushings, clamps and connectors shall be subject to
approval of the Purchaser / Consultant.
4. All rigid conduit fittings shall conform to the requirements of IS: 2667, 1976.
Galvanized steel fitting shall be used with steel conduit. All flexible conduit fittings
shall be liquid tight, galvanized steel. The end fittings shall be compatible with the
flexible conduit supplied.
5. All individually mounted equipment and devices shall be connected to the supply
conduit, using not more than one meter of flexible conduit adjacent to the equipment or
device. Flexible conduit shall be installed in all conduit runs, which are supported by
both building steel and structures subject to vibration or thermal expansion .This
shall include locations where conduit supported by building steel or foundation
becomes supported by steam generator framing.
b) Single conduit support shall be one-hole cast straps and clamp backs unless other types
are acceptable to the Purchaser. Multiple conduit bank supports shall be constructed of
special galvanized support channels with associated conduit clips.
8. Conduit sealing, explosion proof, dust proof and other types of special fittings shall
be provided as required by these specifications and shall be consistent with the area and
equipment with which they are installed. Fittings installed outdoors and in damp
locations shall be sealed and gasketed. Hazardous area fittings and conduits
sealing shall conform to NEC requirements for the area classification.
9. Bidder shall provide double locknuts on all conduit terminations not provided with
threaded hubs and couplings. Water tight conduit unions and rain tight conduit hubs
shall be utilized for all the application which shall be exposed to weather. Moistures
pockets shall be eliminated from conduits.
1. The cable sub-trays and the supporting system, to be generally used between
Local/Group JBs and the main cable trays and the same shall be furnished and installed
by the Bidder. It is the assembly of section and associated fitting forming a rigid
structural system used to support the cable from the equipment or instruction enclosure
up to the main cable trays (trunk route).The material of cable tray shall be GI. For Main
cable tray details shall be as per Electrical Volume of the specification.
2. The covers on the cable sub-trays shall be used for protection of cables in areas where
damage may occur from falling objects, welding spark, corrosive environment, etc. &
shall be electrically continuous and solidly grounded. The cable trays shall not have
sharp edges, burrs or projections injurious to the insulation or outer sheath of the cables.
3. The supporting arrangement of cable tray system shall be able to withstand the weight
of the cable and cable tray system. The supporting interval shall not be more than the
recommended span for the above loading for the type of cable tray selected. The tray
shall not overhang by more than one meter from the support at the dead end. As far as
practicable the cable sub-tray system shall be supported from one side only, in order to
facilitate installation and maintenance of cables.
4. The Bidder shall furnish and install the estimated quantities and size of sub trays /
troughs including all required fittings and adaptors on as required basis
6 Inward Bend 25 mm
1. Following types of density meters shall be used based on process fluid and application
requirements:
i. Nucleonic type
ii. Ultrasonic type
2. For nucleonic type density meter, type of detector shall be selected to suit the
application and source strength.
3. The density meter shall include a source with housing, detector with housing control
unit and mounting hardware.
4. The radiation source shall be of sufficient intensity to provide an accurate signal and
response to meet the particular process and piping requirements. The nuclear source
head shall meet the personnel safety requirements of the Nuclear Regulatory
Commission (NRC).
5. The radiation port of the source head shall have a manually operated mechanical shutter
with lock and key that can be opened and closed without removing the source head. The
shutter shall have a locking device to accommodate a padlock and to permit locking in
the closed position with visible indication of shutter position.
6. Type of detector shall be selected to suit the application and source strength.
7. Nucleonic Density meter shall be absolutely safe and reliable. The radiation source
shall be safely double encapsulated in a stainless steel with lead lining capsule so that
no radioactive material can escape from the protective source container.
8. In addition, independent security systems shall be included to ensure that gamma
radiation is only released from the source container when the measurement chamber is
closed and that the source containers are always locked and remains locked while the
chamber is open. This must not only be guaranteed under regular operating conditions,
but also in the case of false operation and power loss.
9. The Ultrasonic sensor shall be insensitive to gas bubbles and transmitters shall be
microprocessor based and shall use digital signal processing technique for signal
conditioning.
10. The Ultrasonic controller shall have data storage facility.
11. The Density meter shall be capable of temperature compensation automatically by
utilizing temperature sensor signal and in addition manually by entering temperature
value via keyboard entry.
12. The controller shall be SMART microprocessor based and have provision of all
required data of the tested part like material composition, absorption coefficients,
temperature compensation, selection of aperture and radiation source, measuring times
and tolerances of the compact density are pre-adjusted and recorded by the controller.
13. The Control unit transmitter shall be capable of processing gauge head signals,
temperature input, flow rate input. It shall have totalized display and individual
parameters display of selected variables.
14. All equipment necessary for standardization and calibration shall be provided.
15. The detector and the transmitter shall have IP65 or better enclosures.
16. The transmitter shall be suitable for surface mounting, with access to all terminals from
the front. Any required signal converter shall be within the transmitter enclosure.
17. The density devices and all associated equipments shall be as per manufacturer’s
standard, heavy-duty design, as required for the application specified herein.
18. Provision for the nitrogen/ compressed air purging facility in the sensor shall be
provided for cleaning the build-up of the material.
(Nicd re-Chargable)
All Pressure and Differential Pr. Switches shall be mounted in LIE having suitable
isolation valves on Incoming lines and drain lines. All drain lines shall be connected to
suitable drain/blow down headers
ALL PLC Panel dimensions, colour shall be uniform throughout the Control Equipment
Room (preferably size 2000 mm x 1200 mm x 800 mm with 100 mm black Base
channel and 15mm anti-vibration pad however same shall be decided during detailed
engineering. Colour of panels shall be follows as :
• Front & Rear and Top colour RAL 9002 (Grey white), End Panel side RAL5012(Light
Blue) Internal colour shall be Brilliant white
• All panels of width 800mm or more shall open with double door from front and rear
sides.
• Panel thickness shall be Side & Top minimum 1.5mm, front and rear door thickness
shall be 2mm, bottom plate thickness 1.5/2mm and gland plate removable type
thickness 3mm.
• Inside Panel minimum 250mm height space shall be provided from bottom gland plate
to Terminal blocks (TBs).
• Panels shall be fitted with proper illumination with LED lamp at Front and at Rear
(2nos on each side for panel width > 600mm & 1 no. on each side for panel width upto
600mm ) with door interlock switches (. Proper cooling fans (1 no. fan at Front & 1no.
fan at Rear) with louvers shall be provided.
• Separat termination panels for control system shall be provided. for DI, DO/Interposing
relays.
• Dedicated Un-fused TB for 24VDC incomer for SOV shall be provided inside the
control system/ PLC Power distribution panel.
• Panel wire way channel shall be minimum dimension 60mm x 100mm, 40mm x 100 on
requirement basis and shall be decided during detailed engineering.
Inside panels side mounting card shall not be installed. Indoor located , free standing
vertical type system cabinets shall be provided with IP-42 enclosure, double doors with
neoprene gaskets
Sufficient number of power receptacles with disconnect switches shall be installed within
panels/desk/enclosure & racks
All materials supplied under this Sub-section shall be suitable for intended service,
process, operating conditions and type of instruments used and shall fully conform to
the requirements of this specification. The material offered by the Bidder shall be from
reputed, experienced manufacturer whose guaranteed and trouble free operation has
been proven.
i. All pneumatic piping, fittings, valves, air filter cum regulator and other accessories
required for instrument air for the various pneumatic devices/ instruments shall be
provided.
ii. This shall include as a minimum air supply to pneumatically operated control valves,
actuators, instruments, continuous and intermittent purging requirements of Local
Instrument Enclosures (LIE) etc.
iii. For individual supply line and control signal line to control valve, 1/4-inch size light
drawn tempered copper tubing conforming to ASTM B75 shall be used. The thickness
of cu-tubing shall not be less than 0.065 inch and shall be PVC coated. The fittings to
be used with copper tubes shall be of cast brass, screwed type.
iv. All other air supply lines of 1/2 inch to 2 inch shall be of carbon steel hot dipped
galvanized inside and outside as per IS-1239, heavy duty with threaded ends. The
threads shall be as per ASA B.2.1. Fittings material shall be of forged carbon steel
A234 Gr. WPB galvanized inside and outside, screwed as per ASA 132.1. Dimensions
of fittings shall be as per ASA 1316.11 of rating 3000 lbs.
01.06.02 Purge Air Connection for Air and Flue Gas Applications
i. The continuous purging with instrument air shall be done, for all air and flue gas
measurements excepting instrument air and service air instruments, at the process
source connection end. Necessary arrangements required for continuous purging shall
be provided inside all the air and flue
ii. For intermittent purging with service air, necessary arrangement inside all the air and
flue gas enclosures shall be provided. The SS three way valve provided in the SS
tubing shall be used for isolating the transmitter & connecting the service air quick
disconnect line.
For steam and liquid measurements, the impulse pipe should preferably slope
downward from source connection to instrument and instrument shall be installed
below the source point. If due to any reason instrument is installed above the source
point, the impulse pipe shold slope upwards continuously and a ‘pigtail’ should be
provided at the instrument to assure water seal for temperature protection. For vacuum
measurements, instruments shall be installed above source point and impulse pipe
should slope upwards.
1. Impulse piping for air and flue gas shall slope upwards and instrument shall be installed
above source point. If this requirement cannot be met special venting or drain provision
shall be provided with vent & drainpipes. This drain is to be connected to plant drain
through open funnel also.
2. All impulse piping shall be installed to permit free movement due to thermal expansion.
Wherever required expansion loops shall be provided. Expansion joints shall be
provided wherever required especially for impulse piping coming in the furnace area.
3. Special accessories such as condensing pots/ reservoirs shall be provided and installed
wherever required. In any case condensing pots shall be provided for all level
measurements in steam and water services, all flow measurement in steam services and
flow measurements water services above 120°C. For drum/ separator level measurement
required balancing chamber shall be provided.
4. Colour coding of all impulse pipes shall be done by the bidder in line with the colour coding
being followed for the parent pipes.
Instrument air & service air headers and their branches with all associated fittings &
accessories shall be provided for giving supply to all consumers, as per the
requirements. Air piping shall be installed always with a slope of over 1/100 to prevent
accumulation of water within the pipe.
Single and multi tubes shall run with the minimum number of changes in direction.
Suitable identification tags shall be provided for easy checkup and for connections.
Impulse piping and sample piping shall be supported at an interval not exceeding 1.5
meters. Each pipe shall be supported individually using slotted angle mounted clamps
with necessary fixtures. Tubing shall run in proper perforated trays with proper
cover. Tubing shall be supported inside the trays by aluminium supports. Hangers and
other fixtures required for support of piping and trays shall be provided, either by
welding or by bolting on walls, ceilings and structures. Hanger clamps and other
fastening hardware shall be of corrosion resistant metals and hot dip galvanized.
General Requirements
(a) This specification covers the standards, scope of work, documentation, scope of
installation, testing and commissioning of instrumentation work and the various
requirements to be adhered during the execution of the instrumentation works.
Instrumentation works shall be performed in accordance with this technical
specification and various other drawings and schedules submitted and approved by the
Consultant during the execution and the instructions from the Consultant’s or
Purchaser’s Engineer-in-Charge or his authorized representatives during the progress of
the work. Any confusion in any clause should be pointed out by the Bidder and should
get clarifications prior to quoting, otherwise decision of the Engineer-in-Charge shall be
final. All consumables required for the job shall be supplied by the Bidder.
(b) Any recalibration of the instruments required during the loop checking and
commissioning shall be done by the Bidder free of cost during the commissioning of
PLC. All the control systems and protection & interlocking system supplied shall be
checked and commissioned by the Bidder.
(c) All materials fabricated and installed shall conform to the latest edition of applicable
codes and standards. Work shall be carried out in accordance with the various
International & Indian Standards and any local statutory regulations as applicable, listed
below, and though not limited to them:
ANSI : American National Standard Institute, B2.1 Pipe Threads B16.5 Steel
BS : British Standards.
IS : Indian Standards.
The work shall also conform to installation standards, approved hook up drawings, and
support standards. Layout drawings or any other drawings, documents or schedules
submitted by the Bidder and approved by the Purchaser / Consultant.
(d) Only the best trade practices shall be used and highly competent engineers, supervisors
and skilled workers shall be employed for execution of the job. Utmost care shall be
taken during execution of this work to avoid any untoward accidents. All safety rules
and precautions shall be taken care of. The Bidder shall carry out his work in neat,
workmanlike manner. Any substandard quality of job can be rejected by Engineer-in-
Charge. No extra charge can be claimed for such re-work.
(e) The Bidder shall protect all instruments, fittings, tubings and painting during
construction or while in storage from physical damage, contamination by dirt, sand,
water, and any other foreign material.
(f) All site-mounted instruments, junction boxes, air headers, tubing and wiring
terminations shall be labelled or tagged in a manner approved by the Engineer-in-
Charge. Terminals for electrical connections shall be numbered and identified to
indicate polarity, ground connections, test connections and any other pertinent
information.
The specification provides the general guidelines to be followed for the warehousing,
handling, testing, erection, pre-commissioning checks and commissioning of various
types of instruments and accessories.
1. The guidelines provided shall not be deemed as an effort to describe the entire work
involved or to identify the steps and sequence to be adhered to in the erection of specific
work items.
4. For special instruments viz. analyzers etc., the specification furnished are of general
nature only and manufacturer's recommendation shall be strictly followed as guideline
for erection and commissioning.
5. The specification shall not be treated as comprehensive. Any activity, not specifically
mentioned but felt essential or advisable from good engineering consideration shall be
performed.
1. Care should be taken to avoid damage to the instruments during handling and
transportation. Special care shall be taken while handling breakable, spillable, fragile
and delicate items.
2. Before erection, all instruments shall be subjected to calibration and other functional
checks at Bidder's site laboratory. The instruments shall be unpacked with utmost care
and as per instructions furnished on the respective packages, using appropriate tools and
implements.
3. All instruments, jigs, tools and tackle for the purpose of performing the tests shall be
provided by Bidder.
4. All instruments shall be tagged with engraved aluminium / stainless steel tag plates
and shall be secured to the instrument with metallic wire fasteners, during the test.
8. For instruments where the extent of damage is such that the same cannot be repaired at
site, a failure report shall be generated by Bidder, enumerating the nature of fault /
damage. Cases where the damages are only superficial and which does not affect the
appearance and performance of the instrument/s, the decision as to whether such
instruments are fit for erection shall solely lie with Purchaser / Consultant.
9. In no case, erection work shall be taken-up in areas where heavy equipment movement
is foreseen, major welding activity is under progress, heavy structural items are being
erected or any other major activity is being carried out or is anticipated, which may
cause damage to the erected instrument or its support.
10. If any erected instrument or its accessories are found to be vulnerable to damage or to
be fouling / interfering with progress of other activities in the area, same shall be
dismantled / removed. During re-erection of such instruments, all the necessary steps as
indicated in the specification for the erection of the instrument shall be carried out
afresh.
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11. After erection, the instruments shall be covered with transparent polyethylene sheets to
protect from unauthorized handling.
12. Coloured PVC adhesive tapes shall be put on the polyethylene cover to indicate various
stages of activities. Red tape shall indicate erection under progress. Yellow tape shall
indicate completeness of erection. Blue tape shall imply approval of erection and Green
tape shall signify the commissioning of the instrument. Adhesive paper tapes shall be
fixed on the respective tapes to inscribe the dates of completion of activities
13. Location of field instruments shall be consistent with tapping points on pipes and
equipment.
14. No field mounted instrument shall be installed in such a manner that it depends on
rigidity of the impulse piping or the electrical connection to it for support.
15. Handrails shall not be used, in general, for mounting or supporting instruments.
16. The place where the instrument is to be installed must be easily accessible from nearest
floor / platform level and there must be enough clear space to allow maintenance work
and lay-down.
17. The installed position must be such as not to cause any inconvenience to repair,
removal, observation, inspection and maintenance of the installed equipment and other
items nearby.
18. The nearby high temperature equipment or process piping shall not give rise to any
injurious effect to instruments.
19. There shall be no safety valve or effluent drain point which may cause injurious
effect near the instrument. In general, no instrument shall be erected in areas prone to
vibration.
20. Instruments which are outside the building or shed and are not located within
transmitter rack shall be provided with protective cover or canopy to provide effective
protection against dust, rain, sun etc. The cover shall be provided immediately after
mounting the instrument.
21. All clamps, supports, stands etc. required for installation and erection of instruments
and their accessories, shall be painted.
24. Wherever practicable the height of the instrument from its working floor / platform
shall be between 1000-1400 mm. The illumination at the locations where instruments are
located shall be adequate so that the scales can be read unassisted.
25. Sub-trays, where required, shall be erected for proper routing of the cables and tubes and
no cable shall be laid unsupported.
26. The indicating meters shall be oriented properly so that the scale can be read unassisted
and unobstructed from the approach floor / platform.
1. All manifolds, cocks and valves shall be pressure tested at rated hydraulic test pressure.
All air line and draft / vacuum service cocks and valves shall be leak tested.
3. All tests on the transmitters shall be performed after mounting / connecting of the
manifold / valve assembly.
4. For transmitters located in transmitter racks, the erection activities shall normally
include mounting of the transmitter with its manifold / valve assembly on appropriate
support structures in the rack with proper fasteners, viz. U-clamps, bolts etc.,
proper levelling of the transmitter, all pipe connections from process to the
transmitter, piping from transmitter to drain valve / vent valve, supporting / clamping
of the valve, pipe connections from transmitter / valve to drain pot / drain header /
nearest system drain, cabling from transmitter to the rack / external junction box
using flexible conduits, termination of the cable with appropriate lugs, sleeves
and markers, mounting and connecting all settling chambers / damper pots /
siphons etc., as applicable.
5. All cables shall be cross-ferruled at both the junction box and element head end.
01.07.04 Pressure Gauges / Switches, Differential Pressure Gauges / Switches
Pressure gauges / switches and differential pressure gauges / switches shall either be
directly mounted on the process pipeline or shall be mounted on local brackets, gauge
boards or open racks depending on accessibility and maintainability
Bidder's scope of erection of junction boxes shall include mounting of junction boxes in
appropriate locations indicated in the drawings, fabrication of necessary supports,
pedestals, brackets, frameworks etc., for erection and final painting of the structures and
the junction boxes.
1. Junction boxes and pull boxes shall be provided for multi-pair / multi- triad / multi-
core cables and compensating cables.
2. Junction boxes shall be provided either with un-drilled removable gland plates or
with knock-outs. Before installation gland plates shall be drilled / knock-outs shall be
removed based on the cable schedule.
3. Ideally the height of junction boxes shall be 1000-1400 mm from the approach floor
level.
2. Impulse lines shall normally terminate at a bulk head union at the top or back side
of the closed type racks. In cases when bulk heads are not available, entry holes
shall be drilled (not gas cut) and properly sealed after installation.
5. Bidder shall suitably support the drain / vent valves, manifolds etc. With the necessary
clamps, bolts, washers etc.
6. Bidder's scope of work shall also include terminating all rack mounted transmitters
with electrical wires / cables in flexible conduits up to the terminal blocks with
necessary cable and conduit supports, clamps, glands, sleeves, conductor markers /
ferrules, lugs etc.
7. Cabling from transmitter rack-up to local junction box through flexible conduits,
supporting and fixing of conduits at both ends, glanding of cables, ferruling and
terminating are in Bidder's Scope of Work.
01.07.07 Conduits
Flexible and rigid conduits shall be used for connecting instruments to the junction
boxes or nearest trays / sub-trays. The activities shall include threading, plumbing,
1. Where threads are required to be formed they shall be cut and cleaned before
conduit reaming.
2. Ends of all conduits shall be reamed to remove all burrs and rough edges.
3. Cutting oil shall be used for threading operation and the dies shall be kept sharp.
5. Conduit shall not be installed on the outside face of exposed columns but shall be
routed on the web or on the inside of the flange of column.
7. A run of conduit shall not contain more than the equivalent of four quarter bends
including those immediately at the outlets or fittings of cabinets.
9. Bending radius of the rigid conduits shall not be less than six times the internal
diameter of the conduits.
10. Rigid conduits shall be regularly clamped at intervals of not more than 600 mm.
11. Flexible conduits shall be installed in conduit runs across expansion joints.
12. All screwed joints shall be properly sealed with sealing compound to make them
thoroughly water proof.
13. Loop shall be provided in the flexible conduit while joining with rigid conduit,
enclosure or detector. Flexible conduit shall not be kept under tension.
14. Flexible conduits shall essentially be used for connecting instruments or equipment
subjected to vibration, expansion or thermal movement. In all such cases adequate loop
lengths shall be provided to allow free movement at the connected points.
15. Not more than 40% of conduit area shall be taken up by cables.
Erection of sub-trays / supports shall include sub-tray sections up to the main trays. In
areas where main trays are not available, tray sections shall be laid up to the master
junction boxes / local panels / cable spreader areas. Bidder's scope of work shall include
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laying and supporting of trays, fabrication of trays wherever required, painting of trays
and supports and associated minor civil work wherever required.
2. Trays shall be used to run SS / PVC coated copper tubes and electrical cables and shall
be mounted on steel structures and along the pipe racks wherever convenient. Special
stands / supports have to be fabricated wherever required.
3. The erection of trays shall include fabrication, welding and installation of racks
including supports from structural and installation of various sizes of tray in position.
Trays shall be screwed or bolted to the supports.
4. The supports shall be welded to the main structures, grouted in the walls / roof or
welded to the plate inserts. Welding of supports to main equipment / piping shall never
be allowed. Welding or gas cutting of trays shall not be allowed.
5. The scope of work shall also include the supply, fabrication and fixing of supports,
bends, offsets, corners, tees, crossings etc. as per requirement.
6. Civil / masonry works like grouting, providing inserts, chipping the concrete, bricks etc.
for providing supports etc. shall be included.
7. Bidder shall arrange to provide hangers, jigs, inserts and other fixtures on walls,
ceilings, structures and permanent scaffolding etc., for fixing racks. Fabrication and
fixing of necessary jigs, hangers, inserts and other fixtures, as required, shall be
considered a part of erection of structural steel work.
8. The trays shall be properly finished and laid to give neat appearance.
9. Cable trays shall be fixed on angle iron supporting racks fabricated at site.
12. If any erected tray or its supporting structures are found to be vulnerable to damage or
to be fouling / interfering with progress of other activities in the area, the same shall be
dismantled and re-erected.
13. The decision, whether to use rigid conduit or sub-tray shall be judiciously decided.
01.07.09 Earthing
Bidder's scope of work shall include the earthing of all instruments / equipment,
enclosures and other metallic parts and objects. Necessary wires, lugs, sleeves, markers
/ ferrules etc. shall be supplied. In addition to the general guidelines given below,
Bidder shall remain responsible to follow the instrument / equipment manufacturer's
grounding recommendation.
1. Screens of all screened cables between field instruments to local junction box shall be
terminated to individual terminal blocks. The other end of the screen shall be left
disconnected and taped with adhesive vinyl tape. All screen terminal blocks at JB end
shall be shorted with shorting links. The screen of multipair / triad cables to cabinets
shall be connected to the screen terminal block in JB and the other end to be grounded
at panel end only.
3. All junction boxes, stands, stanchions, local panels, cubicles etc., must be connected to
the nearest riser of electrical earth mat by SWG 10 galvanized steel wire.
4. All control panels, desks, consoles, cubicles, cabinets etc. must be physically earthed
with the electrical ground mat inside the Control Room area.
6. All local panel and central panel instruments shall be grounded to the common ground
bus available inside the panel. Normally the grounding wires shall be available as
wired-up inside the panels. Wherever grounding wires are not available inside the
panel, the same shall be provided by Bidder.
7. For terminating grounding wires only ring-tongue type lugs shall be used.
Instrument piping and tubing work shall include the impulse piping work between
Take-off valves on pipe lines or equipment / take-off nozzles and the instrument,
the drain piping to the nearby drain point, instrument air sub-header and main header
(wherever required) installation and testing and copper tubings between air header /
sub-header to different instruments / consumers.
1. This section enumerates the basic guidelines for erection of primary impulse
piping, all associated fittings on primary impulse piping, piping for all instrument
drain and vent lines with all associated valves and fittings, impulse line support and
routing with accessories, all impulse line accessories viz. condensing pots,
temperature equalizing columns, seal chambers, settling columns, drain headers etc.
connections between instruments and valves / manifolds and their testing.
2. For impulse piping / tubing routing, Bidder shall develop a field routing sketch.
3. The pipes shall be cut with a hacksaw or high speed cutting emery wheel, squarely
and all burrs shall be removed. Roller type tube cutters shall not be used.
4. Cold bending of the pipes shall be performed with the use of a proper pipe bender
with radius of bends greater than five times the outside diameter of the pipe / tube.
Allowable deformation shall be within 4%.
5. Impulse piping shall always be installed with a slope greater then 10% in proper
direction for draining and shall never be installed in level horizontally.
6. Piping shall run with the minimum of changes in direction consistent with good
practice and neat appearance.
7. The bends / offsets must be smooth and regular. Bending shall not exceed 90 Deg.
in any case. Necessary couplings, unions, fittings etc. shall be provided on impulse
lines to facilitate removal and maintenance of instruments conveniently.
Erection of instrument air distribution piping include connection from nearest main air
header take-off valves to the vicinity of air consumers viz. control valves, pneumatic
1. Supply and installation of all intermediate pipe fittings, isolation valves etc. including
supply and installation of necessary clamps and supports shall be considered as in
integral part of instrument air piping work.
2. For instrument air sub-header work, carbon steel hot-dipped, inside and outside
galvanized pipes shall be used. Only fittings of carbon steel galvanized threaded
type shall be used for GI application.
3. Outlets of air headers shall be provided with 1/2" isolation valves, for up to 7 consumers.
Bidder shall install GI sub-headers up to vicinity of the consumer and thereafter 6 mm
OD PVC coated copper tube shall be laid.
4. All headers and sub-headers shall be thoroughly cleaned before installation by means of
compressed air.
5. All headers and sub-headers shall be supported properly. The distance between any
two supports shall not exceed one meter unless otherwise required to suit site condition.
Bidder's scope shall include PVC coated copper tubing shall be used for the signal
and supply air to transmitters, control valves, servo drives, impulse line purge
connections, solenoid valves, local controllers, I/P converters etc. with all necessary
fittings and air filter regulators, wherever required.
1. The tubes shall be thoroughly cleaned and flushed with air before
installation and defective tubes detected during checking, if any, shall be removed.
2. Single tube runs of PVC coated copper shall be joined together by means of straight
connector (double compression fitting) at every joint of the tube or shall be
telescopically brazed and sleeved.
3. The individual single run pneumatic signal tubing shall be run and connected from
the field mounted instruments to locally mounted controllers / indicators
mostly on tray work or on angles.
4. Tubes shall be run with the minimum number of changes in direction consistent
with good practice and neat appearances. Tube runs shall be properly dressed, neatly
laid and adequately clamped / supported on angles / trays. Distance between any
two supports shall not exceed one meter in any case.
5. Tubes installed but not connected shall have ends suitably closed to prevent the
entry of foreign materials.
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6. Tube runs shall be provided with suitable identification tags indicating the run
number for easy correlation and identification of connections. Identification ferrules at
both ends shall be provided.
8. When tightening up the nuts of the compression type fittings, spanner of suitable
size shall be used. To avoid any deformation to the compression ring, adjustable
wrench shall never be used.
9. The bending radius for single tubes shall be more than five times the outside
diameter of the tubes. The tubes shall be bent with proper benders and care shall be
taken not to cause flattening of the bend.
10. The tubes shall be properly dressed on the trays to remove bends, dents etc. Tubes
shall not be directly hit by steel hammers.
11. Aluminium clamps or self-locking straps shall be used for clamping the tubes on trays
/ angles and same shall be supplied by Bidder at his own cost.
12. When connecting PVC coated copper tubings on servo-drives / valves mounted
on structures having thermal movement, sufficient expansion loops shall be formed
at the ends to allow for equipment movement without developing any stress on the end
fittings.
For orifice plates with flange taps Bidder's scope shall include fixing of nipple and first
take-off valve, fixing and supporting condensation pot (wherever applicable) and
insertion of orifice plate with suitable gaskets, nuts and bolts. For orifice plates with D,
D/2 tapping, pipe welded stubs shall be available.
The general guidelines for installation of orifice plates are given below.
1. The length of the take-off nipples shall be sufficient so that the first take-off valve
protrudes beyond the thermal insulation.
2. The take-off nipples shall be screwed / welded according to the design requirement.
3. The hand wheel of the take-off valves shall be so oriented that they can be operated
conveniently from approach platform, ladder etc. Otherwise approach platform, ladder
shall be provided.
4. For steam services, condensation pots shall be connected to the tapping point before or
after first take-off valves. Utmost care shall be taken to ensure that both the
condensation pots are at the same level. All necessary bracing, saddle etc. shall be
fabricated and used to support the condensation pots with the main pipe.
5. Orifice plates shall be inserted with proper orientation with respect to fluid flow in line.
6. Orifice plate should only be inserted in position for checking the alignment. Thereafter, it
shall be withdrawn and preserved till pre-commissioning activities are over.
7. Bidder shall supply suitable gaskets while fixing the orifice plates in position.
8. The orifice bar handle, shall be so oriented that the imprints are readable unassisted
from the access floor of platform.
Flow Nozzles shall normally be shop assembled in branch pipe and welded in position
with main pipe. The flow nozzles shall generally have D-D/2 tapping and shall be shop
assembled with take-off nipples and root valves. Bidder's scope of work shall include
connecting the condensation pots (for steam services) before installation of the
differential pressure instrument.
01.07.16 Control Room Control Panels / Desks, Consoles and Cubicles / Cabinets
This section provides guidelines for the erection of desks, panels, consoles,
cabinets etc., in the Control Room, Control Equipment Room, Local Control Room
and other such locations.
1. After Inter-sectional bolting with necessary nuts and bolts, inter-sectional wiring shall
be terminated at both ends.
2. Bidder shall arrange anchor bolts or grouting spikes and grout the same in the pocket.
Any civil job concerned with the proper installation of the panel shall be considered as
part of the panel installation work.
3. After installation, the main incoming fuse of each panel section shall be removed and
preserved till commissioning.
01.07.17 Main Control Room / Computer Room Panels / Desks and Consoles / Local
Control Panels / Consoles and Desks
1. Erection of panels and desks in Control Room area shall involve precise alignment and
matching of surfaces. Bidder shall perform all related activities to achieve an aesthetic
completion of the job. All necessary realignment, foundation work, packing and filling
shall be done to compensate for shifting, waviness, misalignment etc.
2. When bolting the panel sections, care shall be taken not to leave excessive strain on any
of the surfaces. All necessary packing and filling materials shall be provided.
3. Instruments and accessories supplied loose for mounting on panels shall be installed
only after installation of the panels.
4. Tools and tackle recommended by the desk / panel / console manufacturer shall only be
used.
7. Bidder's activities shall also include splitting of gland plates, if required, to admit plug-
in connector, mounting of special cable clamps on the gland plates and dressing,
routing and clamping of the prefabs within the panel / desk / console.
8. All insulated conductors shall be tested with a 500 volt megger or an equivalent testing
device. Insulation resistance measurements shall be made between each conductor and
ground and between each conductor and all other conductors of the same circuit.
Minimum acceptance resistance values
01.07.18 Functional and Pre-Acceptance Test
The authorized quality assurance personnel of Bidder shall conduct all tests as per the
requirements of approved quality assurance program and fully satisfy in compliance
with specification requirements by all equipment / sub-systems and the system as a
CONTROL & INSTRUMENTATION SYSTEM Page 113 of 119
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Bidder shall have to furnish system description, operational write-up, bill of materials,
drawings, data, information, technical catalogues, test certificates and other details
required to fully establish the capability and performance of the equipment and systems
offered. Any bid not containing sufficient details to fully describe the equipment and
systems offered may be treated as non-responsive and hence rejected. Bidder shall
submit the drawings and documents with good spiral binding. Loose documents /
drawings will not be accepted at any stage.
i) Process and instrumentation (P&I) diagrams for the FGD system and all auxiliary
equipment indicating all mounted instruments and PLC displayed measurement using
ISA symbols and using suitable tag numbers against each instrumentation equipment.
Alarm and interlock functions shall also be indicated in the P&I diagrams.
ii) Detailed technical literature of each C & I system and instrumentation equipment
offered.
iv) List of commissioning and recommended spares for all the equipment supplied along
with unit price
A. For approval
i) Finalised process and instrumentation (P and I) diagram for FGD system and auxiliary
units indicating all local and remote measurements, controls, alarms and interlock
functions, using ISA symbols and using suitable tag numbers against each
instrumentation equipment.
ii) Finalised instrument list for the entire plant indicating type of instrument, make, model
number, process conditions (max/operating pressure, temperature), scale range,
quantity, application and tag number (as per P and I diagram).
iii) Detailed specification datasheet for each instrumentation item/ equipment including
cables indicating finalised make, model no., application, scale range, quantity, tags no.
(as per P&I diagram), accuracy, power consumption etc. Data sheets for each
instrument as per standard format shall be submitted with all the required details filled
in.
v) Instrument power supply diagram with specification and bill of quantities of electrical
accessories.
vi) General arrangement drawings and sectional views of various cabinets, panels including
gauge boards, transmitters cabinets & racks etc., showing internal disposition of all
components/ units with dimensional details and bill of materials.
i) Detailed technical literature/ catalogue for each instrumentation item and control
equipment, highlighting the selected model numbers.
ii) Design data, sizing calculation and selection criteria along with all related charts, curves,
tables and fabrication drawings of Flow sensors, control valves and actuators.
iii) Instrumentation layout drawing showing location of sensors, control valves, transmitters
etc. and route of cables from these up to Control Room.
v) Wiring and termination diagrams with details of termination of field signals to local JBs/
panels and from JBs to panels/ marshalling racks/ cabinets and consoles including
internal wiring drawings.
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viii) List of commissioning and recommended spares for all the equipment supplied along
with unit rate.
ix) Manufacturer’s test, calibration and guarantee certificates for all instruments and control
equipment.
x) Operation and maintenance manuals for instruments and control equipment (In English
language).
xii) Soft copy of all the above drawings and documents in CDs / DVDs/ suitable electronic
media.
Any other relevant data, drawings / documents and information necessary for review of
items whether specifically mentioned or not, shall be furnished by the Bidder. The
quantity of drawings and documents to be submitted to Purchaser / Consultant shall be
as per contract.
01.08.04 Following Drawings and Documents shall be submitted for PLC based automation
system. All communications in the drawings, documentations, technical literatures and
manuals shall be in English language.
iii) Technical specifications with literatures of all the units of the Control System viz.
Processing units, process I/O unit, sequence event recorder, device indicating operator’s
guidance message, data bus, communication unit etc. indicating make, model numbers,
features and application.
iv) List of reference of similar system already in service with complete performance record
details
A. For Approval
i) Finalized system configurations diagram for the automation system alongwith its
peripherals with list of hardware and write-up on the system.
ii) Bill of Material and final technical specification with detail data sheet for all PLC
equipments such Processors, Communication modules, Power supply cards, I/O unit,
panels, console, Operator stations, Engineering Station, Servers, printer, bus & N/W
cables, communication hardware etc indicating make, model numbers.
iii) Overall General arrangement drawings and sectional views of various cabinets, panels,
consoles, etc. showing internal disposition of all components/ units, with dimensional
details and bill of materials.
iv) Control room layout drawing showing disposition of panels, consoles, desks, etc with
dimensional details.
ii) Single line power supply diagram with specification and bill of quantities of
electrical accessories.
iii) Detailed technical literature/ catalogue for Automation system with peripherals,
highlighting the model number.
iv) Wiring and termination diagrams for all RI/Os, Marshalling racks, Cabinets, Consoles
etc.
v) Cable schedules.
viii) Formats and work sheets for generation and display of overview, groups, loops,
graphics, alarms, operator’s guide messages, real time and historical trends, log and shift
formats.
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ix) Detailed listing of application software, system software, HMI software, etc and the
number of licenses with detail features and functional descriptions.
x) Manufacturer’s test, calibration and guarantee certificates for all instruments and
automation system.
xi) Operation and maintenance manuals for Automation system (In English
language).
xii) List of commissioning and recommended spares for automation system along with unit
rate.
xiii) Soft copy of all the above drawings and documents in CDs / DVDs/ suitable electronic
media.
Any other relevant data, drawings / documents and information necessary for review of
items whether specifically mentioned or not, shall be furnished by the Bidder. The
quantity of drawings and documents to be submitted to client / consultant shall be as per
contract.
a) Before starting manufacture of the fabrication, Bidder shall secure approval on the
design drawings from Purchaser / Consultant for the drawings in writing. Any
manufacture done prior to approval of the drawings shall be rectified in accordance with
the approved drawings by Bidder at his own cost and the equipment shall be supplied
within the stipulated period.
b) Bidder shall submit within stipulated time from the date of receipt of approved drawings
as per GCC - eight (8) sets of final drawings along with one (1) set of soft copy for each
drawing & document loaded in suitable (CD/ DVD/ other) medium. Bidder shall also
provide fifteen (15) sets of latest version of Instruction Manuals along with one (1) set of
soft copy, loaded in suitable (CD/ DVD/ other) medium, for I & C system including its
various components, sub-assemblies, indicating the method of installation, check-ups
and tests to be carried out during erection and before commissioning of the equipment.
The manual shall also include instruction for step checking, trouble shooting and fault
rectification for different components and sub-assemblies.
c) Bidder shall also incorporate all modifications in the drawings carried out at site during
trial run, start-up performance and guarantee tests till hand over of the units to Purchaser
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and submit these final as-built drawings each in ten (10) copies along with one softcopy
loaded in suitable (CD/ DVD/ other) medium.
d) Care shall be taken to present all final documents in proper form. All catalogs and
literature (including sub-supplier’s catalogs), Datasheets, Instrument list, consolidated
I/O list for PLC system, Function Control diagram, Loop diagrams, PLC configuration
diagram shall be bound together in indexed volumes for keeping in plant library. All O
& M manuals shall be in handy size and neatly bound for carrying to the work place.
TENDER SPECIFICATION
FOR
SEMI DRY FLUE GAS DESULPHURIZATION
(FGD) SYSTEM & ITS AUXILIARIES
VOLUME – IV
ELECTRICAL SYSTEM
MECON LIMITED
RANCHI – 834 002
INDEX TO VOLUMES
Volumes Title
Volume – I Commercial
Volume – II Technical
Volume - IIA General Technical Specification
Section 01.00 Preamble
Section 02.00 Intent of Specification
Section 03.00 Project Information
Section 04.00 Special Instructions to Bidder
Section 05.00 Scope of Work, Supply & Services
Section 06.00 Quality Assurance System / Requirement
Section 07.00 Painting
Section 08.00 Finalization of Sub-vendors / Sub-contractors
Section 09.00 Performance Guarantees
Section 10.00 Terminal Points & Exclusion
Section 11.00 Layout and Maintenance Requirement
Section 12.00 Drawings / Documents to be submitted along with Bid / Offer
and after award of Contract
Volume -IIB Technical Specification
Section 01.00 Flue Gas Desulphurization System
Section 02.00 Technical Data Sheets – Mechanical
Volume -IIC Balance of Plant (BOP)
Section 01.00 Water Supply Facilities System
Section 02.00 Air Conditioning & Ventilation System
Section 03.00 Elevators, Cranes & Hoists
Section 04.00 Fire Protection System
Section 05.00 Piping, Valves & Fittings
Section 06.00 Thermal Insulation, Lagging, Cladding
Section 07.00 Compressed Air System
Volumes Title
Volume - III Instrumentation & Control System
Volume -IV Electrical System
Volume -V Civil, Architectural & Structural Works
Volume -VA Civil Works.
Volume -VB Architectural Works
Volume -VC Structural Works
Volume -VI Mandatory Spares and Tools & Tackles
Volume -VII Tender Drawings
SECTION-I
GENERAL DESCRIPTION :
For 4x210MW units of existing power plants of Mettur TPS-1, semi dry limestone based
FGD (Flue Gas Desulphurisation) unit is proposed covering Absorbers, Booster Fans and
associated auxiliary systems.
21. Electrics associated with hoisting & handling system including cranes.
22. Electrics associated with elevators.
23. Erection Materials/Installation Hardware – 1 lot
24. Commissioning Spares as per OEM recommendations – 1 lot
25. Cable Supporting Structure, Cable Trays – 1 lot (For cable routing, existing
Trestle/Structure shall be utilised to the extent possible – in areas where the same
will not be available, suitable structures/trestles shall be provided by the bidder)
For incoming power supplies for one of the 6.6KV FGD HT Switchboards, two nos. of
incoming feeders shall be made available by TanGedCo from available transformer
feeders (each 1250A VCB) in existing 6.6KV Station Switchgear (Station Bus C1, feeder
reference “ESP TRFR(Com)” and “PDFACS TRFR-1”).
Similarly, for incoming power supplies for another 6.6KV FGD HT Switchboards, two
nos. of incoming feeders shall be made available by TanGedCo from available transformer
feeders (each 1250A VCB) in existing 6.6KV Station Switchgear (Station Bus C2, feeder
reference “TIE TO C3” and “PDFACS TRFR-2”).
Maximum load (in MVA) for electrical operation of proposed FGD systems shall be
indicated in the offer by the Bidder. In this context, bidder shall note that maximum power
that can be made available from the existing station transformer viz. ST-1 & ST-2 (rating
31.5MVA each) is limited upto 10MVA each (i.e total 20MVA for proposed FGDs for all
four units of power plant) inclusive of all design and operational margins. Incase, the
connected load designed by the bidder exceeds 10MVA for FGD for each of 2x210MW
units, the capacity enhancement of existing station transformers viz. ST-1 & ST-2 and
allied HT bus C1 & C2 including busduct, incoming breaker and bus shall be in the scope
of the bidder.
1250A VCB feeders, two each from Station Bus C1 & C2 in existing 6.6kV Station
Switchgears, shall be used as two incomers to each of the new 6.6KV HT Switchboards to
be located in the proposed FGD Electrical Cum Control Room building. Replacement of
1250A VCB breakers by 2000A VCB breakers with necessary modification/changes in
power, control, protection, metering & associated components like new VCBs (2000A,
40KA, 7.2kV, floor mounted, bushing CTs, core balance CTs, relays, meters etc. including
retrofitting of the new 2000A VCB in the existing available breaker cubicle and achieving
Vol. – IV ELECTRICAL SYSTEM Page 2 of 152
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TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
one to one interchangeability), two each from existing 6.6kV station bus C1 & C2 shall be
under bidder’s scope. Required HT Cables from these modified 2000A VCB panels up to
FGD 6.6KV new HT Switchboards, including laying and termination at both ends and
allied works, shall also be covered under the scope of the bidder of FGD package.
(Approximate distance 500meter each).
It is envisaged that from two nos. of new FGD 6.6KV HT Switchboards, total three nos. of
VCB, 1250A Transformer feeders (each restricted to draw a maximum load of 180A) shall
be allocated for use as power supply feeders viz. “ESP TRFR(Com)”, “PDFACS TRFR-1”
and “PDFACS TRFR-2” respectively. (Approximate distance 200meter each).
All HT motors of FGD (>160KW) shall be fed from new 6.6KV HT Board through 1250A
VCBs. New 6.6KV HT Board shall be housed in the Electrical building in new FGD area.
(‘SLD’ to be referred for details of HT drives)
Taking two feeders from new 6.6KV FGD HT Board, FGD LT PMCC shall be fed
through FGD LT Substation [6.6/0.433KV, 2.0 MVA (approx.)]. LV neutral shall be
provided with NGR and NDR and the neutral current shall be limited to < 1 Amp.
From PMCC, 415V LT supplies (ACB feeders) shall be made available to respective
MCCs in different load centres as well as to all LT drives rated above 90KW and up to
160KW. Further distribution of LT 415 V power to different drives shall be made through
different MCCs/PDBs.
Key Single Line Diagram (Drg. No. MEC/11/E1/10KP/TS/004, rev. 01, sheet 1 of 1) is
attached.
A.C. drive motors up to 160KW 415 V, 3 phase, 3 wire, with NGR earthed
DC drive motors 220 V, 2 wire, unearthed D.C.
Control and protection of LT 220 V D.C.
switchgears including VCBs of HT
board and ACBs of PMCCs
Control and indication voltage (other 240 V, 1 phase, line & neutral (through
than breakers) control transformers)
UPS 240 V, 1 phase, 2 wire
Metering 110 V, AC, PT supply
Plant illumination 240 V, 1 phase, line & neutral
Emergency illumination 220 V D.C.
Panel lighting and space heaters 240 V, 1 phase, 2 wire, 50 Hz, A.C. with
one point earthed
DCS/PLC/PLC power supply 240 V, 1 phase, 2 wire, 50 Hz, A.C. (UPS
supply)
Welding socket / power receptacles 415 V, 3 phase, 50 Hz, A.C. outlets
240 V, 1 phase, 2 wire, 50 Hz, A.C. with
one point earthed
Permissible variations :
Voltage Frequency
+6% to –6%
+10% to -15%
Permissible variation with rated performance and (LT systems)
control effectiveness maintained +5% to –5%
(HT systems)
Permissible voltage dip at HT switchgear bus
(-) 15% ------
during starting of HT motor
Permissible voltage dip at LT switchgear bus
(-) 15% ------
during starting of LT motor
415 V 50 kA 105 kA
220 V DC 10 kA --------
[The rated short circuit withstand duration for 6.6kV switchboard will be 3.0 Secs,
whereas for 415 V switchgears including MCCs, it will be 1.0 sec.]
Construction Power :
Two nos. 415V feeders at one location shall be made available by the purchaser
approximately 300meters from FGD battery limit. Further distribution to various loads of
the bidder shall be in the scope of the bidder. Bidder shall arrange necessary DBs,
capacitor banks along with APFCR, cables etc. for the distribution
SECTION-II
General :
In general, Circuit Breaker & Panels shall be supplied from the (same) unit / factory that
supplied the Circuit breaker/ panels on which successful type test was conducted.
Manufacturer of the switchgear panel shall be same as the manufacturer of Circuit Breaker. The
switchgear shall be of Indoor metal clad bolted/riveted design (with in house fabrication, pre-
treatment & powder coating facilities), single bus bar , self standing, dust proof construction,
internal arc tested for designed fault current for 1 sec., indoor cubicle type fitted with VCB in
fully truck mounted so that it directly rolls on to the floor when taken outside without usage of
any external breaker handling truck. Switchgear should be tested as per IEC for highest system
voltage for all short circuit duties.
1250A VCB feeders, two each from station bus C1 & C2 in existing 6.6kV station
switchgears, shall be used as two incomers to each of the new FGD HT switchboards to be
located in the proposed FGD electrical cum control room building. Replacement of 1250A
VCB breaker by 2000A VCB breaker with necessary modification / changes in power,
control, protection, metering & associated components like new VCBs (2000A, 40KA,
7.2KV, floor mounted, bushing CTs, core balance CTs, relays, meters etc., including
retrofitting of the new 2000A VCB in the existing available breaker cubicle and achieving
one to one interchangeability), two each from existing 6.6KV station bus C1 & C2 shall be
under bidder’s scope.
Required HT Cables from these modified 2000A VCB panels up to FGD 6.6KV new HT
Switchboards, including laying of cable & termination at both ends and allied works, shall
also be covered under the scope of the bidder of FGD package. (Approximate distance
500meter each)
Separate earthing trucks (Two nos.) shall be provided by the Bidder for maintenance
work. These trucks shall be suitable for earthing the switchgear busbars as well as
outgoing / incoming cables or busducts. The trucks shall have a voltage transformer and
an interlock to prevent earthing of any live connection. The earthing trucks shall in
addition have a visual and audible annunciation to warn the operator against earthing of
live connections.
1) Closing of the earthing switch if the associated circuit breaker truck is in Service position.
2) Insertion of the breaker truck to Service position if earthing switch is in closed position.
3) Closing of the earth switch on a live connection. Three (3) nos. voltage capacitive dividers
shall be provided on each phase of the section intended for earthing and three nos. "RED"
neon lamps connected to these on the panel front for visual indication.
4) Energising an earthed Section:
Complete details of arrangement offered shall be submitted during detailed engineering ,
describing the safety features and interlocks.
The earthing device (truck / switch) shall have the short circuit withstand capability equal
to that of associated switchgear panel. 4 NO + 4 NC of auxiliary contacts of the
earthing device shall be provided for interlocking purpose.
All hinged doors shall be earthed through flexible earthing braid.
01.02.04 One set of special tools and tackles for 6.6 KV Switchgear.
01.02.05 Mandatory spares
01.02.06 All relevant drawings, data and instruction manuals.
01.02.07 In addition to all the outgoing feeders required for bidder’s own system,
bidder shall provide in each switchgear the following HT feeders as a minimum
a) Three (3) numbers 1250A transformer feeders (VCBs along with requisite control,
metering protection with associated components), One from one bus of HT switchboard
for U1 & 2 and other two from each bus of HT switchboard for U3 & 4 for use by the
customer for “ESP TRFR (Comm)”, “PDFACS TRFR-1” and “PDFACS TRFR-2”
(max. load 180A each)
b) One (1) number highest rated motor feeder breaker as spare
c) One (1) number lowest rated motor feeder breaker as spare
d) One (1) number highest rated Transformer feeder breaker as spare
03.07.00 The switchgear busbar rating shall be at least equal to the rating of
incomer. Each incomer of HV switchgear shall be rated to carry continuously minimum
120 percent of Name Plate rated current of all the connected equipments. Ratings of Bus-
coupler and Tie Breaker shall be equal to the rating of the incomer breaker of the
respective board.
03.08.00 For indicative requirement of power distribution scheme, the enclosed Single
Line Diagram (SLD) shall be referred. All the ratings, if shown in the above drawing
represent the indicative figures as a tentative requirement only. Exact rating, number and
type of feeders etc. shall be decided by the bidder and the same shall be indicated in the offer.
This shall be subject to review and approval by the purchaser/consultant based on relevant
sizing calculations along with SLD and List of Drives to be submitted along with the offer by
the bidder.
For easy interchangeability, number of ratings to be selected for breakers shall be of
two types. One for incomers, bus coupler & tie feeder (if applicable) and another common
rating for all other outgoing transformers, motors and board feeders
04.00.00 Specific Requirements
04.01.00 Construction
- Each transport unit not more than 3.2m.
- Removable lifting arrangement for each transport unit.
- Screwed wire mesh for busbar and CT chambers to prevent accidental contact with live parts.
- Explosion vents for different chambers
- Pressure relief flaps which can not be opened from outside to release pressure that builds up
in the event of arcing faults inside the cubicle.
04.01.01 The switchgear shall be indoor, metal-clad, floor mounted, draw
out type. Design and construction shall be such as to allow extension at either end.
04.01.02 The switchgear enclosure shall conform to the degree of protection IP:5X
for VT/relay compartment and IP:4X for other compartments. The minimum thickness
of CRCA / Alu zinc sheet steel used shall be 2 mm and gland plates shall be 2.5mm thick
made of hot/cold rolled sheets & 3mm for non-magnetic material .
04.01.03 The switchgear assembly shall comprise a continuous, dead-front, line-up of
free standing, vertical cubicles. Each cubicle shall have a front hinged door (with door
not forming part of the withdrawable truck) with latches and a removable back cover.
All covers and doors shall be provided with neoprene gaskets.
04.01.04 Switchgear cubicle shall be so sized as to permit closing of the front access
door when the breaker is pulled out to “rack out position”. The working zone shall be
restricted within 750 mm to 1950 mm from floor level.
04.01.05 Circuit breakers, instrument transformers, bus-bars, cable compartment etc.,
shall be housed in separate compartments within the cubicle. The design shall be such
that failure of one equipment shall not affect the adjacent units.
04.01.06 All relays, meters, breaker control switches, selector switches and indicating
lamps shall be flush mounted on the respective cubicle door or on control cabinet built
on the front of the cubicle. AC/DC auxiliary supply switches / isolation switches for
cubicle space heater, cubicle lamp, spring charging motor circuit shall be located inside
metering compartment. For all the energy meters, Test terminal blocks shall be provided.
04.01.07 Dummy panel shall be provided in the switchgear line up, if required, for easy
termination access of power and control cables. Dummy panel / bus trunking panel shall
be of full cubicle with closed roof and rear door similar to enclosures for active
cubicles.
04.02.00 Bus and Bus Taps
04.02.01 The main buses and connections shall be of high conductivity
aluminum/aluminum alloy, control & auxiliary buses of electrolytic copper/copper wires
sized for specified current ratings with maximum temperature limited to :
a) For bolted joints (Plain or tinned) : 90oC (i.e. 400C rise over 500C ambient)
b) For bolted joints (Silver plated) : 105oC (i.e. 550C rise over 500C ambient)
c) For continuous busbars : 85°C (i.e 35°C rise over 50°C ambient)
04.02.02 Bus bars shall be of same size for the entire length of the switchgear.
Continuous current rating of bus connections / dropper shall be same as that of continuous
in panel current rating of associated breaker.
04.02.03 All bus connections shall be silver plated. Adequate contact pressure shall be
ensured by means of two bolts connection with plain and spring washers and locknuts.
Bimetallic connectors shall be furnished for connections between dissimilar metals.
04.02.04 Bus bars and connection shall be fully insulated for working voltage
with adequate phase/ground clearances. Insulating sleeves for bus bars and cast-resin
shrouds for joints shall be provided, suitable for maximum temperature rise of bus bars.
04.02.05 Bus insulator shall be high strength, hygroscopic, non- combustible arc
& track resistant type with creepage distance suitable for heavily polluted atmosphere.
Use of inflammable materials like hylam is not acceptable.
04.02.06 All buses and connections shall be supported and braced to withstand
stresses due to maximum short circuit current and also to take care of any thermal
expansion.
04.02.07 Bus bars shall be color coded for easy identification and so located that the
sequence R-Y-B shall be from left to right, top to bottom or front to rear, when viewed
from front of the switch-gear assembly.
04.03.00 Circuit Breaker
04.03.01 Circuit breaker shall comprise of vacuum type, three pole, identical single pole
type interposing units, operated through a common shaft.
04.03.02 Circuit breakers shall be with horizontal isolation and horizontal draw
out type, having SERVICE, TEST and DISCONNECTED positions with positive
indication for each position. Circuit breakers shall be capable of racking in and racking
out with the door in closed condition
04.03.03 Circuit breakers of identical rating shall be physically and electrically
interchangeable.
04.03.04 Circuit breaker shall have motor wound spring charged trip free mechanism
with anti pumping-feature and shunt trip. In addition facility for manual charging of
spring shall be provided. Power supply to the spring charging motor shall be cut off when
closing spring is charged manually.
04.03.05 For motor wound mechanism, spring charging shall take place automatically
after each breaker closing operation. One open-close-open operation of the circuit
breaker shall be possible after failure of power supply to the motor.
04.03.06 Mechanical safety interlock shall be provided to prevent :
a) The circuit breaker from being racked in or out of the service position when the
breaker is closed.
b) Racking in the circuit breaker unless the control plug is fully engaged.
04.03.07 Automatic safety shutters shall be provided to fully cover the female primary
disconnects when the breaker is withdrawn.
04.03.08 Each breaker shall be provided with an emergency manual trip, mechanical
ON-OFF, indication, an operation counter and mechanism charge/discharge indicator.
04.03.09 Each breaker shall be provided with following :
a) Auxiliary switch, with 6 NO + 6 NC contacts, mounted on the draw out portion of the
switchgear.
b) Position/cell switch with 3 NO + 1 NC contacts, one each for TEST and SERVICE
position.
c) Auxiliary switch with 4 NO + 4 NC contacts mounted on the stationary portion of
the switchgear and operated mechanically by a sliding lever from the breaker in SERVICE
position. Alternatively electrically reset type latching relay may be used for the
purpose.
d) Spring charge limit switch with 2 NO + 2 NC contacts.
04.03.10 Switch contact shall be rated 10 A
AC and 2A DC at their respective operating voltage.
04.04.00 Control & Indication
The circuit breaker shall be wired up for local & remote operation. Each breaker
cubicle shall be equipped with following :-
04.04.01 One (1) local remote selector switch stay put type with pistol grip handle and
Vol. – IV ELECTRICAL SYSTEM Page 11 of 152
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TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
key interlock.
04.04.02 Breaker control switch (T-N-C) shall be of spring return to normal and with
pistol grip handle.
04.04.03 Five (5) indicating lights on front of compartments :-
GREEN : Breaker Open
WHITE : Spring Charged
RED : Breaker Closed
BLUE : Trip circuit healthy
AMBER : Auto trip
04.04.04 Lamps shall be clustered type LED module pilot lights in
thermoplastic enclosure with polycarbonate lens and diffuser. LED shall be protected by
in-built fuse with surge suppressor and leakage voltage glow protection. Lamp and lens
shall be replaceable from front.
04.05.00 Current Transformer
04.05.01 Current transformers shall be cast resin type. All secondary connections shall
be brought out to terminal blocks where wye or delta connection shall be made.
Metering & protection CT secondary Terminal blocks shall be of link type with provision
for shorting.
04.05.02 Accuracy class of the Current Transformers shall be :-
a. Class PS for differential relaying (or as required depending on the type of relay
selected)
b. Class 5P20 for other relaying
c. Class 0.5 for metering.
d. Class 0.2S for performance / precision ABT metering.
e. Class of Insulation shall be ‘E’ or better.
04.05.03 Current transformer secondary shall be rated for 1A or 5A, depending on
requirement
04.05.04 Feeders requiring remote metering and/or current monitoring shall be provided
with current transducers with calibration for full-scale reading.
Other particulars of the CTs, like ratio, burden, knee point voltage, excitation current
and secondary resistance shall be decided by the bidder and shall be furnished for
review/acceptance of the client/consultant during detail engineering.
Core balance CTs (CBCT) having CT ratio of 50/1A shall be provided on outgoing
motor and transformer feeders. These CBCTs shall be mounted inside the switchgear panel.
The window size of CBCT's shall be based on the overall diameter of the cables, to be
finalized during detailed engineering.
The CBCT and earth fault relays shall be properly coordinated to ensure:-
(a) Proper operation and entire range of earth fault current
(b) Prevent inadvertent operation due to motor starting current, transformer switching
inrush current and short circuit current.
04.06.00 Voltage Transformer
04.06.01 Voltage Transformer (VT) shall be cast-resin, draw out type and shall have an
accuracy class of 0.5/3P Bus PTs. BUS PTs and Line PTs shall be mounted in
separate vertical panel. Class of Insulation shall be ‘E.
04.06.02 High voltage windings of voltage transformer shall be protected by
current limiting fuses. The voltage transformer and fuses shall be completely
disconnected and visibly grounded in fully draw-out position.
04.06.03 Low voltage winding of voltage transformer shall have MCB, installed in
all ungrounded secondary leads. MCB shall be suitably located to permit easy
replacement while the switchgear is energized.
04.07.00 Relays
04.07.01 Relays shall be of draw out design with built-in testing facilities and
flush mounted at the front of panel. Small auxiliary relays may be in non-draw out
execution and mounted within the cubicle.
04.07.02 Relays shall be rated for operation on 110V secondary voltage and 1A or
5A secondary current to be decided by the bidder. Number and rating of relay contacts
shall suit the job requirements.
04.07.03 All protective relays shall be micro processor based multifunction type
numerical relays. All relays shall be able to communicate with DCS/PLC/Plant Control
System through IEC 61850 communication protocol.
Numerical relays of all modules in a switchboard shall be serially interfaced to plant
DCS/PLC/Plant Control System. Each breaker shall be monitored from DCS/PLC/Plant
Control System
Numerical relay shall have communication on three ports, local front port to laptop and
dual ports on IEC 61850 to connect to data concentrator through LAN.
Serial communication link shall have 100% redundancy.
Numerical relays and DCS/PLC/Plant Control System shall have common protocol for
proper communication.
Control of the Breakers shall be from DCS/PLC/Plant Control System through interposing /
Coupling relays which shall be located in the respective panels.
selector switches shall have make before break feature to prevent open circuiting of CT
secondary.
04.11.00 Fuse & MCB
04.11.01 Fuses shall be HRC, link type, with minimum interrupting capacity equal
to the listed short circuit current. Fuses shall be furnished complete with fuse bases and
fittings.
04.11.02 MCBs shall be three/four pole, trip free, with manual close / open
mechanism. Automatic tripping provision for over load and short circuit shall also be
provided. MCBs shall be rated for full fault level of the system. MCB shall be provided
with required number of auxiliary contacts as per circuit requirement.
04.12.00 Push Button
Push button shall be heavy duty, shrouded, push to actuate type with colored button
and inscription plate. Each push button shall have 2 NO + 2 NC contacts, rated 10A
and 0.5A at their respective AC and DC operating voltage.
04.13.00 Secondary Wiring
04.13.01 The switchgear shall be fully wired at the factory to ensure proper functioning
of control, protection, transfer and interlocking schemes.
04.13.02 Fuses and links shall be provided to permit individual circuit isolation from
bus wires without disturbing other circuits. All spare contacts of relays, switches and
other devices shall be wired up to terminal blocks.
04.13.03 Wiring shall be done with flexible, 660V grade, PVC insulated switchboard
wires with stranded copper conductors of 1.5 Sq. mm. Flexible wire of 2.5 mm2 shall be
used from CT to relay chamber.
04.13.04 Each wire shall be ferruled by plastic tube with indelible ink print at both end
having terminal block no., terminal numbers, destination no. as per approved Wiring
Diagram.
04.13.05 Wire termination shall be made with crimping type connectors with
insulating sleeves. Wires shall not be spliced between terminals.
04.13.06 All spare contacts of relays, timers, auxiliary switches shall be wired up to the
terminal block.
04.14.00 Terminal Blocks
04.14.01 650V grade, multi way terminal block complete with mounting
channel, binding screws and washers for wire connections and marking strip for circuit
identification shall be provided for terminating the panel wiring. The terminals shall be
screw or screw less (spring loaded)/cage clamp type with lugs. All panel wiring for
external connections shall terminate on separate TBs which shall be suitable for
connecting two stranded conductor of 2.5 sq mm on each side or alternatively TBs shall
have the possibility of double shorting space to facilitate looping (typical). Terminals for
Vol. – IV ELECTRICAL SYSTEM Page 15 of 152
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METTUR THERMAL POWER STATION - I (4X210MW)
C.T. secondary leads shall have provision for shorting and grounding. For CT wiring,
Disconnecting type TBs shall be provided.
04.14.02 Not more than two wires shall be connected to any terminal. Spare terminals
equal in number to 20% active terminals shall be furnished. Separate terminal blocks shall
be used for AC/ DC wiring termination.
04.14.03 Terminal blocks shall be located to allow easy access. Wiring shall be so
arranged that individual wires of an external cable can be connected to consecutive
terminals. All terminals going out of the switchboard shall be connected /wired to a separate
terminal block marked “External Termination”. These shall be easily accessible.
04.14.04 Terminal blocks used for interface with DCS/PLC/Plant Control System via
termination cabinet shall be suitably sized to facilitate proper termination of interconnecting
cables.
04.15.00 Cable Termination
04.15.01 Switchgear shall be designed for cable entry from bottom. Sufficient space
shall be provided for ease of termination and connection.
04.15.02 All provisions and accessories shall be furnished for termination and
connection of cables, including removable gland plates, cables supports, crimp type
tinned copper/ aluminum lugs, brass compression glands with tapered washer (Power
cables only) and terminal blocks.
04.15.03 Gland plates shall be minimum 3 mm thick. The gland plate and supporting
arrangement for Incoming power cables shall be of aluminum.
04.15.04 Sufficient space shall be provided between the power cable termination and
gland plate. Core balance CTs wherever specified, shall be accommodated within this
space, inside the cubicle. Sufficient space and support arrangement shall be available inside
each panel to accommodate HT cable termination kits and sealing kits suitable for the size
and number of XLPE, Aluminum cables to be terminated.
A minimum clearance of 600 mm shall be kept between cable lug bottom ends and gland
plates for stress cones for XLPE cables.
Dummy panels shall be provided adjacent to the switch panel where the required
number of cable termination can be accommodated in the cabling chamber of the main
panel. Rear extension not acceptable.
04.16.00 Bus Duct Connection
04.16.01 Bus duct connections, wherever provided shall be furnished along with
transition panel if required. Bus duct connections shall be generally from the top without
exceeding allowable temperature rise.
04.16.02 All connecting bus work shall have the same continuous rating as associated
switchgear bus and shall be fully braced for the listed short circuit current.
04.16.03. All provisions such as matching flange and other accessories required for
Vol. – IV ELECTRICAL SYSTEM Page 16 of 152
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CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
drawings. Type of labels and fixing of labels shall be such that they are not likely to peel
off / fall off during prolonged use.
04.19.04 Caution notice on suitable metal plate shall be affixed at the back of each
vertical panel.
04.20.00 Space Heaters and Plug Sockets
04.20.01 Each cubicle shall be provided with thermostat controlled space heaters and
5A, 3 pin plug socket.
04.20.02 In addition, motor feeder cubicle shall be wired-up for feeding the
motor space heater through suitable rated breaker auxiliary NC contact and/or
contactor.
04.20.03 Cubicle heater, Motor heater, Plug/socket circuits shall have individual
switch fuse units.
04.21.00 A.C/D.C Power Supply
04.21.01 Necessary 415V AC and 220V DC power supplies as required for control and
service, shall be arranged by the bidder. Duplicate feeders shall be arranged for AC
and DC supply.
04.21.02 MCCB/MCB shall be provided at each switchgear for the incoming
supplies, 4-pole, for AC and 2-pole, double throw and off for DC. Automatic changeover
scheme shall be provided for the two incoming feeders for DC supply.
Provision for Alarm/annunciation at remote shall be provided for ‘DC supply failure’ for
each of incoming feeders.
04.21.03 Bus-wires of adequate capacity shall be provided to distribute the incoming
supplies to different cubicles. MCCB/MCB/Isolating switch fuse units shall be
provided at each cubicle for AC/DC supplies. Provision for Alarm/annunciation at remote shall
be provided for ‘panel AC supply failure’ & ‘panel DC supply failure’
04.21.04 AC load shall be so distributed as to present a balance loading on three-phase
supply system.
04.21.05 DC Sub circuits (Control, spring charging motor , indication etc.,) of each panel
shall be protected by HRC fuses.
04.21.06 Control Supply Arrangement
(a) DC feeders of adequate rating shall be used for DC control supply of each
switchboard. DC feeders shall be terminated in bus-coupler breaker or bus PT module or
central panel of the switchboard with facility for auto changeover for DC supply.
(b) Isolating MCB of adequate rating shall be provided for incoming DC Control supply
feeders.
(c) DC control bus wire shall run throughout the length of the switchboard and DC
power supply for each cubicle shall be tapped through isolating MCBs of adequate rating,
for control, signaling, protection and motor circuit. Each incoming and sub-circuit shall be
Vol. – IV ELECTRICAL SYSTEM Page 18 of 152
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TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
provided with separate MCBs. Main and sub-circuit MCB shall be selected to ensure
selective clearance of sub-circuit fault.
(d) Availability of DC control supply shall be supervised by auxiliary relay with
adequate number of NO/NC contacts for DC supply healthy indication on the switchboard
and failure of DC supply annunciation in DCS shall be provided.
(e) Auxiliary relays shall be provided instead of contactors wherever there is a
continuous application of 220V DC control supply. The auxiliary relays shall be rated for
240V DC.
(f) Similar arrangement shall be made for 240V single phase AC auxiliary power
supply for space heater, 240V inter panel illumination and plug point circuit for hand lamp
connection.
04.22.00 Tropical Protection
04.22.01 All equipment, accessories and wiring shall have fungus protection,
involving special treatment of insulation and metal against fungus, insects & corrosion.
04.22.02 Screens of corrosion resistant material shall be furnished on all ventilating
louvers to prevent the entrance of insects
04.23.00 Painting
4.23.01 All surfaces shall be sand blasted, pickled and grounded as required to
produce a smooth, clean surface free of scale, grease and rust.
4.23.02 After cleaning, the surfaces shall be given a phosphate coating followed by 2
coats of high quality primer and stoved after each coat.
4.23.03 The switchgear shall be finished in light gray color with two coats of
powder paint. The coating shall be done electro statically followed by stoving.
4.23.04 Sufficient quantity of touch-up paint shall be furnished for application at site.
04.24.00 Accessories
Following accessories shall be furnished along with each Switchgear :
a. Earthing equipment suitable for earthing the bus.
b. Earthing equipment suitable for earthing the outgoing cable.
04.25.00 Each board shall be supplied with
1 set of test plugs.
Any other special purpose tools for maintenance.
5.00.00 Tests
5.01.00 The switchgear shall be completely assembled, wired, adjusted and tested at
the factory as per the relevant standards.
5.02.00 Routine Test
The tests shall include but not necessarily limited to the following :
Vol. – IV ELECTRICAL SYSTEM Page 19 of 152
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The Numerical Relay for 6.6kV Switchgears shall comply with but not limited to the
following technical requirements.
ANNEXURE-A
RATINGS AND REQUIREMENTS
ANNEXURE-B
PROTECTIONS
01.00.00 In case any trip function is not available in a single relay, separate
numerical relays shall be provided to achieve the requirement.
02.00.00 All protective relays shall be provided with self reset type of contacts.
03.00.00 Apart from protection relays, each breaker shall be provided with
separate discrete auxiliary relays for anti-pumping (94), trip
annunciation (30), trip supervision (74), electrically reset type
breaker contact multiplication (52X) relay and lockout (86)
functions. Lockout relay shall be hand reset type. For
multifunction relays however, trip circuit supervision function as
an integral feature of the relay is acceptable. Individual trip circuit
supervision function shall be provided with respect to each trip coil of
circuit breaker.
04.00.00 Numerical under voltage relays (27) with time delay relay
including VT fuse failure relay shall be provided for Bus VTs.
05.00.00 IDMTL relay version shall be decided as per system requirement and
the same shall be finalized during detail engineering.
06.00.00 Zero-sequence CT and associated relay combination shall be
such as to ensure a pick-up sensitivity of 10A primary ground fault
current.
07.00.00 Separate locked rotor protection relay (50 LR) with auxiliary relay
(50 LRX) shall be furnished, if required.
08.00.00 Separate numerical differential relay to be provided for motor 1000
KW and above , Transformer 10MVA and above with separate C.T. of
P.S. Class.
(b) Buscoupler
filled)alarm
• Differential protection (for transformers
rated 10MVA and above)
• Restricted Earth Fault protection (64R),
Stand by earth fault protection (51N)
The above list (for metering & protection) is indicative only. Bidder shall provide all
metering and protection features necessary for smooth, trouble-free, satisfactory
functions of the equipment and accessories
ANNEXURE – C
A. HT SWITCHGEAR - ELECTRICAL
1. Incomers – 1 & 2
a. Breaker Close DO
b. Breaker Trip DO
c. Breaker ON DI
d. Breaker OFF DI
e. Switchgear Disturbance (Control Supply DI
Fail)
f. Numerical Relay Unhealthy DI
g. Trip Coil Healthy DI
h. DC Supply-1 Fail DI
i. DC Supply-2 Fail DI
j. Switchgear Available (Breaker in service / DI
Spring Charged / Switchgear in Remote)
k. Electrical Trip (Lockout relay operated) DI
l. Interface through IEC
Numerical Relay
61850 protocol
2. Line PT – 1/2
a. Line PT under voltage DI
b. Line PT Fuse Fail DI
c. PT in service position DI
3. Bus-coupler
a. Breaker Close DO
b. Breaker Trip DO
c. Incomer-1 Check Syn DO
d. Incomer-2 Check Syn DO
e. Bus Coupler Check Syn DO
f. Breaker ON DI
g. Breaker OFF DI
h. Switchgear Disturbance (Control Supply DI
Fail)
i. Numerical Relay Unhealthy DI
j. Trip Coil Healthy DI
k. DC Supply-1 Fail DI
l. DC Supply-2 Fail DI
m. Switchgear Available (Breaker in Service / DI
Spring Charged / Switchgear in Remote)
n. Electrical Trip (Lockout Relay Operated) DI
Vol. – IV ELECTRICAL SYSTEM Page 29 of 152
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TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
03.07.00 The transformer shall be installed in hot, humid and tropical atmosphere.
All equipment, accessories and wiring shall be provided with tropical
finish to prevent fungus growth.
03.08.00 The dry type transformers shall be epoxy cast resin/ resin encapsulated
type. They shall be naturally cooled (AN) and moisture proof. Insulating
materials used in construction shall be of low smoke emitting type, less
flammability and free from toxic gas emission.
04.00.00 Specific Requirements
04.01.00 Enclosure for Dry Type Transformer
04.01.01 The transformers shall be housed in enclosures fabricated from sheet steel of
minimum 2mm thick. Degree of protection of the enclosure shall be at least
IP33. Screens shall be perforated sheet steel type. Mesh size shall be such that
lizard, rats etc. cannot enter inside the enclosure.
04.01.02 The enclosure shall be adequately reinforced to ensure rigidity so as to permit
transportation of transformer within enclosure. Base frame for mounting the
transformer shall be minimum 4 mm thick and shall be provided with
bi-directional rollers/mounting skid.
04.01.03 Double leaf access, both at front and at rear end, shall be provided with
concealed hinge and neoprene gaskets for easy access and also for withdrawal
of core and coil assembly if required. Enclosure door shall have provision of
padlocking in door-closed position.
04.01.04 Enclosure shall be provided with lifting eyes and pulling lugs Heavy removal
parts shall be provided with eyebolt for ease of handling.
04.01.05 Each transformer shall be provided with one set of bi-directional rollers
for rolling the transformer parallel to either centre line.
Enclosure temperature during full load operating condition shall be limited to below
70ºC.
04.02.00 Core & Coils
04.02.01 The transformer may be of core or shell type. The core shall be built up with
high grade, non-aging, low loss, and high permeability grain oriented cold-
rolled silicon steel laminations especially suitable for core material.
04.02.02 The coils shall be manufactured from electrolytic copper conductor and fully
insulated for rated voltage. For dry type transformer of encapsulated design,
HV & LV coils shall be separately encapsulated under vacuum in cast resin
compound.
04.02.03 Insulating material shall be of proven design, Coils shall be so insulated that
impulse and power frequency voltage stresses are minimum. For dry type
transformer the insulating material shall be glass fibre reinforced conforming
to class `F’. Coils shall be so insulated that impulse and power frequency
Vol. – IV ELECTRICAL SYSTEM Page 33 of 152
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TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
voltage stresses are minimum and are suitable to withstand even the
severest of temperature fluctuation.
04.02.04 All leads from the windings to the terminal board and bushings shall be
rigidly supported to prevent injury from vibration or short circuit stresses.
Guide tube shall be used where practicable.
04.02.05 The core and coil assembly shall be securely fixed in position so that no shifting
or deformation occurs during movement of transformer or under short circuit
stresses.
04.03.00 Tappings
04.03.01 Off-circuit taps as specified shall be provided on the high voltage winding.
04.03.02 The transformer shall be capable of operation at its rated KVA on any tap
provided the voltage does not vary by more than ±10% of the rated voltage
corresponding to the tap.
04.03.03 The winding including the tapping arrangement shall be designed to maintain
electromagnetic balance between HV and LV windings at all voltage ratios.
04.03.04 The tap changing shall be effected manually by change of copper link at the
terminal board inside the enclosure.
The HV winding of the transformer shall be brought out through suitably rated
bushing mounted on non magnetic material in separate air insulated cable box.
The cable box shall also be provided with facility for supporting from ground.
04.04.00 Safety Interlock
For all dry type transformers following safety interlocks shall be provided :
a) A safety interlock shall be provided to ensure that the enclosure door can be
opened only when transformer is de-energised.
b) Safety limit switches operated by door-handle shall be provided for tripping
HV & LV side breaker.
04.05.00 Bushing
04.05.01 Transformer HV bushings and LV bushings can be either solid porcelain or
epoxy type. Bushing shall be suitable for satisfactory operation in the high
ambient temperature inside Bus Duct enclosure (if applicable). LV flange
area shall be of non-magnetic material.
04.05.02 Bushings shall be provided with terminal connectors of approved type and size.
04.05.03 Bushing location shall provide adequate phase and ground clearances.
04.05.04 The bushings shall be suitable for a heavily polluted atmosphere.
04.06.00 Terminal Arrangements
04.06.01 The physical position of terminals and markings shall be as per the relevant
Vol. – IV ELECTRICAL SYSTEM Page 34 of 152
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TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
standards.
04.06.02 Terminals for bus duct connection shall be brought through top cover mounted
bushings with matching flange.
04.06.03 Bushing terminals and flange shall be coordinated with bus duct.
04.06.04 Terminals for cable connection shall be brought out through top cover/side wall
mounted bushings to a detachable cable-end box with disconnect link.
04.06.05 Cable-end box shall be self-supporting, weatherproof, air filled type
with sufficient space inside for termination and connection of cables.
04.06.06 Cable-end box shall be furnished complete with removable gland plate, double
compression brass glands, tinned copper lugs, armour clamps and necessary
hardware.
04.06.07 In general, the arrangement shall be such as to permit removal of the
transformer and core/coil assembly without dismantling the bus duct/cable
installation.
04.06.08 Low voltage winding neutral shall be brought out thru' top cover mounted
bushing. Two ground conductors 75x10 G.I. flats shall run from
neutral bushing to the bottom of the tank over pin insulators for connection
to two different neutral earth pits.The earth pits shall be treated type.
04.07.00 Marshalling Box
04.07.01 For Marshalling Box the sheet steel used shall be at least 1.6 mm thick cold
rolled. The box shall be tank mounted type.
04.07.02 The degree of protection shall be IP-55.
04.07.03 Wiring Scheme shall be engraved in a stainless steel plate with viewable font
size and the same shall be fixed inside the Marshalling Box door.The
marshalling box shall be provided with cubicle lamp with door switch,
space heater with thermostat and removable cable gland plate. All terminal
blocks shall be located in this box.
Three (3) Nos. resistance winding temperature detectors / thermistors/PT-100 shall be
provided in LV winding of each transformer. Transformers shall be provided
with adequate No. of embedded temperature detectors/temperature scanners
for remote indication in DCS and necessary indication instruments (WTI) in
local.
Epoxy moulded Neutral CTs (2 Nos.) of required ratings for REF and Backup
earth fault protection shall be provided
04.08.00 Wiring
04.08.01 All control, alarm and indication devices provided with the transformer shall
be wired upto the terminal blocks.
04.08.02 Wiring shall be done with 650V PVC wires in conduit or PVC armoured
cable. Minimum wire size for control wiring shall be 1.5 sq.mm stranded
copper and for CT/PT wiring the size shall be 2.5 sq.mm stranded copper.
Not more than two wires shall be connected to a terminal. 10% spare terminals
shall be provided.
04.08.03 Multi-way terminal block complete with mounting channel, binding screws
and washers for wire connections and marking strip for circuit identification
shall be provided for terminating the panel wiring. Terminals shall be stud
type, suitable for terminating 2 nos. 2.5 mm2 stranded copper conductor
and provided with acrylic insulating cover.
04.08.04 All devices and terminal blocks shall be identified by symbols corresponding
to those used in applicable schematic or wiring diagram. Each wire shall be
identified, at both ends, with interlocking type permanent markers bearing
wire numbers as per Bidder's Wiring Diagrams. AC/DC wiring shall have
separate color-coding. 20% spare terminals shall be provided.
04.08.05 Wire termination shall be made with crimping type connectors with
insulating sleeves. Wires shall not be spliced between terminals.
04.09.00 Grounding
04.09.01 For dry type transformers a ground bus rated to carry the maximum fault current
shall extend full length of the enclosure.
04.09.02 The ground bus shall be provided with two bolt drilling with GI bolts and nuts
at each end to receive the GS flats for earthing. Each flat shall be designed for the
earth fault current as specified in this specification.
04.09.03 The core coil assembly shall be directly connected to this ground bus by
removable bolted link for effective grounding.
04.09.04 Ground terminals shall be also provided on marshalling box to ensure its
effective earthing.
04.09.05 For continuity of earth connection, all gasketted joints shall be provided with
braided copper wire jumpers.
04.10.00 Painting
04.10.01 All steel surfaces shall be thoroughly cleaned by sand blasting and/or chemical
agents, as required, to produce a smooth surface free of scales, grease and
rust.
Vol. – IV ELECTRICAL SYSTEM Page 36 of 152
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TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
04.10.02 The external surfaces, after cleaning, shall be given a coat of high quality red-
oxide or yellow chromate primer followed by filler coats .
04.10.03 The interior and exterior surfaces shall be finished with specified color shades
as per IS-5.
04.10.04 Sufficient quantity of touch up paint shall be furnished for application
after installation at site.
04.10.05 The paints shall be carefully selected to withstand tropical heat, rain etc. The
paint shall not scale off or crinkle or be removed by abrasion due to normal
handling.
04.10.06 All supporting structures and hardware shall be hot dip galvanized.
05.00.00 Tests
5.01.00 Routine Tests
During manufacture and on completion, all transformers shall be subjected to
the routine tests and acceptance test in accordance with latest IS/IEC in
presence of the purchaser or his representative.
5.02.00 Type Tests
Type test certificates shall be furnished for similar type and rating of
transformers. If certificates are not available or not meeting the
requirements , they have to be type tested, free of charge, to prove the
design.
However, following type tests shall be performed on one of each rating of
transformer, even if type test certificates are submitted by the Bidder for
Purchaser's approval:
a) Impulse withstand test
b) Temperature rise test
5.03.00 Miscellaneous
All component parts and auxiliary equipment such as bushings, etc. shall be
routine tested as per relevant Indian Standards.
06.00.00 Drawings, Data & Manuals
06.01.00 Drawings, data & manuals to be Submitted.
06.01.01 Typical general arrangement drawings showing enclosure, core coil assembly
and terminal arrangement etc. for dry type transformers.
06.01.02 Transport/shipping dimensions and weights, space required for handling parts
for maintenance.
06.01.03 Technical leaflets on major components and fittings.
ANNEXURE-A
Ratings And Requirements
1.0 Application : Auxiliary transformer(dry type)
ANNEXURE-B
FITTINGS AND ACCESSORIES
Each transformer shall be equipped with fittings and accessories, as listed below:
1. Digital winding temperature scanner with electrical separate contacts of alarm and trip.
2. Handling & lifting lugs for both enclosure and core-coil assembly.
3. Jacking pad for core-coil assembly.
4. Flat type bi-directional rollers with locking arrangement for core-coil assembly.
5. Inspection cover for cable end box.
6. Door handle operated safety limit switch with 1 NO + 1 NC contact.
7. Ground bus.
8. IP-55 marshalling box.
9. Rating and terminal marking plate.
Note:
All indication, alarm, trip contacts provided shall be rated for 0.5A at 220 V DC and 5A
at 240 V AC.
The exact number of boards shall be finalized by the bidders based on actual
engineering requirement to be finalized during detail engineering stage.
01.02.00 Base channel frame of all boards along with necessary mounting hardware is
included.
01.03.00 All relevant drawings, data and instruction manuals.
02.00.00 Codes and Standards
IEC : 60947, IS : 13947
02.01.00 All equipment and materials shall be designed, manufactured and tested in
accordance with the latest applicable Indian Standards (IS) and IEC except
where modified and/or supplemented by this specification.
02.02.00 Equipment and material conforming to any other standards, which ensure
equal or better quality, may be accepted. In such case, copies of the English
version of the standard adopted shall be submitted .
02.03.00 The electrical installation shall meet the requirements of Indian Electricity
Rules as amended up to date and relevant IS Code of Practice. In addition,
other rules and regulations applicable to the work shall be followed.
03.00.00 System concept and Design criteria
03.01.00 415V power distribution in the Plant area shall be by means of PCCs,
MCCs and DBs
03.02.00 The PCCs/PMCCs/MCCs/DBs shall be used for providing power to various
LT loads of the plant. PCCs, PMCCs, MCCs, distribution boards shall be
planned as per requirement in various load centres.
03.03.00 Bidder shall include and provide requisite PCCs, PMCCs, MCCs and
distribution boards for feeding all AC & DC loads including loads like welding
transformers, lighting loads, power sockets, maintenance sockets etc.
03.04.00 The equipment shall be located in a hot, humid, and tropical atmosphere,
heavily polluted at places with coal dust and/or fly ash.
03.05.00 Duty involves direct-on-line starting of large induction motors and also under
certain emergency conditions, automatic transfer of loads from one source of
supply to another.
Motor starting current shall be as per relevant IS for the IE3 motors subject to
tolerance (+20%) as per .IS. PCCs/ PMCCs /MCCs shall be designed
accordingly..
03.06.00 Busbars of PCCs/PMCCs shall be sized to carry continuously the LV side
current of the transformer plus a 20% margin.
Busbars of MCCs/DBs shall be sized to carry continuously the total running
load of the system (including anticipated future load, wherever applicable) plus
a 20% margin.
All busbars shall be capable of withstanding the mechanical forces and thermal
stresses due to maximum short circuit current.
03.07.00 In-cubicle ratings of incomer and bus-section breakers/switches shall be
identical to the associated busbar rating.
03.08.00 For continuous operation at specified ratings, the temperature rise of various
equipment/components shall be limited to the permissible values specified in
relevant standards and/or this specification.
03.09.00 Circuit breakers shall not produce any harmful over voltage during switching
off of induction motors. If required, surge protective devices shall be
included in the scope of supply to limit over voltages.
03.10.00 MCCs shall be used to supply power to contactor controlled motors rated
upto 90kW, local panels, local starter panels etc.
03.11.00 PCCs / PMCCs shall be used to supply power to motor of ratings above 90 to
160KW through ACBs.
03.12.00 Incomers and bus couplers of MCC’s of rating 630Amps and above shall be
through Air Circuit Breakers while incomers & bus couplers of lower rating
shall be through MCCBs.
03.13.00 All Outgoing feeders (non-motor feeders) of PCC/PMCC rated 630A &
above shall be Air Circuit Breakers while rated below 630A shall be MCCB.
03.14.00 Motors upto 90KW shall be provided with MCCB / MPCB, contactors
03.15.00 Motors rated above 90KW shall have comprehensive motor protection
relays. They shall be numerical type and shall communicate with DCS /Plant
Control System through open protocol (IEC 61850).
Height of platform adjustable to suit the levels at which the breakers are
mounted.
Adequate mechanical strength for handling the largest breaker.
Guide rails and stops.
Truck shall be hydraulic operated.
04.02.00 LT MOTOR CONTROL CENTRES
04.02.01 Motor Control Centers (MCCs) shall house breaker panels, MCCB &
contactor operated modules etc. All MCCs shall have duplicate incomers and a
bus-section. All incomers and Bus-coupler shall have ACB’s for MCCs rated
630 Amps and above and shall have MCCB’s for MCCs rated below
630Amps. Suitable interlock shall be provided to satisfy the condition of two
out of three closing. All outgoing feeders shall be breaker/MCCB operated
with or without contactor depending upon the rating and application. All motor
feeders other than those operated through breakers shall have Bi-metal
overload relay with single phase preventor for protection. All motors above 30
kW shall have CT operated overload relay with single phase preventer for
protection. All breaker operated motor feeder modules shall have numerical
motor protection relays that can be interfaced with the DCS/PLC/Control
System. Distribution of outgoing feeders shall be such as to ensure uniform
loading on each section of the MCC.
04.02.02 Constructional Features
General:
Fully drawout type with modules having service, test and isolation positions.
Floor mounting, free standing with base channel for fixing on the inserts on
the floor.
Single front, totally enclosed, dust and vermin proof. However, for extreme
space constraint and/or to suit the overall layout for a chosen space/premises,
bidder may propose, in their offer, double front MCCs for review and
acceptance of the purchaser/consultant. In general, double front MCCs shall
be avoided unless prior intimation by bidder is done and subsequent
acceptance by the owner/consultant is obtained.
Degree of protection IP-54 or better.
Sheet steel with thickness not less than 2.0mm for load bearing and 1.6mm
for other members.
Provision of extension on either end of MCC.
Removable lifting facilities for each transport unit.
Designation plate for each MCC and Inscription plate for each module.
Earth bus shall run throughout the length of MCC at bottom and for each
vertical section.
Busbar configuration shall be red-yellow-blue for three phase AC power and
red - blue for DC control supply from front to back or top to bottom or left to
right as viewed from front.
Temperature rise not to exceed 40 degree C above the peak ambient
temperature of 50 deg C.
Removal of busbars shall be possible without disconnecting external cables.
04.02.04 Control transformer
415/110 dry type – one for each module and one for test bus.
04.03.00 POWER DISTRIBUTION BOARD (PDB) / ACDB
PDB/AC Distribution Board (DB) shall house MCCB modules only. They
shall have duplicate incomers and a bus-coupler. Wherever bus-couplers are
provided, distribution of outgoing feeders shall be such as to ensure uniform
loading on each section of DB. Board shall be single/double front, metal
clad, front matched, dust and vermin proof, draw-out fully,
compartmentalized and extensible on both sides with IP52 type enclosure.
Shall have base channel of size ISMC 75.
Shall have isolated busbar chamber for main busbar at the top, running
throughout the length of the board. Chamber shall have removable cover.
Cable alley shall have sufficient space for aluminium power cables and
bottom cable chamber shall be left free completely isolated from the vertical
busbar.
Busbars shall have same cross section throughout the length. Rating of the
neutral busbar shall be 50% of the main busbar. Earth bus bar shall run in
bottom chamber throughout the length of the panel.
The number of PDBs/ACDBs and their locations shall be decided based on
consumer and shall be finalized during details engineering / drawing
approval stage.
20% of the total feeders shall be kept as spares.
04.04.00 DC DISTRIBUTION BOARDS (220V)
For feeding the 220V /48V DC loads, the DCDBs shall be provided.
DCDBs shall have two incomers and a bus section with suitable interlock
(one out of two logic) between the two incomers. Incomers of DCDBs shall
be breaker operated and outgoing shall be MCCB modules. They shall be
fixed type and floor mounted. Other constructional features shall be similar
to ACDB.
The switch boards shall be provided with suitable quantity and type of
outgoing feeders for the auxiliaries, control supplies to various panels /
systems. For each load and auxiliary, one separate feeder shall be provided.
The feeder rating and quantity shall be as per requirement.
20% of the total feeders shall be kept as spares.
The continuous current rating of the bus bars and incomers for 220V DCDBs
shall be the maximum DC load (excluding the momentary load) on the bus
plus 20% margin rounded off to the next higher standard rating.
04.05.00 AC DISTRIBUTION PANELS
AC Distribution panels, shall have switch fuse units as incomer. Distribution
panels may be fed from DBs and shall have two incomer. AC distribution
Boards shall be of two types - one with 415V, 4-wire, triple pole- and-neutral
(TPN) outgoing feeders and the other with 240V, 2- wire,
single-pole-and-neutral outgoing feeders. The board shall be wall mounted
type and other constructional features as given in above specification for
PDB/ACDB except that fixed type module are accepted for such DBs.
For small loads, MCB boards with TPN MCB as incomer and TPN/SP
MCBs for outgoing may be considered. However, to bring down the short
circuit level to safe limits, isolation transformer shall be provided wherever
necessary. Details of such loads shall be finalized in consultation with the
owner/consultant.
The feeder rating and quantity shall be as per requirement.
20% of the total feeders shall be kept as spares.
04.06.00 A.C. STARTER (CONTACTORS)
a) The contactors shall be three pole, air break type with non-bouncing
silver/silver alloy contacts. The contactor shall be designed for duty as per
Annexure-A attached with this section.
b) Each contactor shall be provided with minimum (2) normally open and two (2)
normally closed auxiliary contacts rated 10A at 240V A.C. The exact
requirement of contacts shall be decided by the bidder taking into account the
scheme requirements and spares.
c) Contactors for forward and reverse direction of reversible drives shall
preferably be both electrically and mechanically interlocked.
d) Delayed dropout contactors, if required and provided for some essential
auxiliaries, shall not dropout on power failure if the voltage is restored within
three seconds.
e) It shall be the responsibility of the Bidder to fully coordinate the overload
and short circuit tripping of the circuit breakers with the upstream and
Vol. – IV ELECTRICAL SYSTEM Page 52 of 152
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CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
General
DC starter panel for Control of DC motors shall be provided. DC starters
shall be complete with switch-fuse units, DC contactors, resistors, overload
relays, meters, push-buttons, lamps, etc.
DC contactor shall be provided with adequately rated magnetic blow out coil
for effective arc quenching.
DC resistance in suitable steps shall be provided.
Contactors DC2 for shunt motor, DC4 for series motors.
Required shunt for current measurement.
DC shunt cable used in DCDB, DC starter panels etc. shall be included
Necessary transducers shall be provided for taking current signal to the PLC /
Plant Control System.
Starters shall be furnished in totally enclosed floor-mounting, sheet steel
cubicles complete with a hinged front access door. Minimum thickness of
sheet steel shall be 2mm.
The cubicle enclosure shall provide dust and humidity protection, the degree of
protection being not less than IP-54.
The resistor enclosure shall be provided with ventilating louvers and wire
mesh guard and shall have a degree of protection IP-23.
Cubicle space heater shall be provided to maintain internal temperature above
dew point. Heater shall be furnished with switch-fuse unit and thermostat
control.
04.08.00 SPECIFIC REQUIREMENTS FOR PCC/PMCC/MCC AND VARIOUS
OTHER BOARDS/PANELS
Vol. – IV ELECTRICAL SYSTEM Page 53 of 152
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METTUR THERMAL POWER STATION - I (4X210MW)
04.08.01 Incomers and Bus couplers of 415V Switchgears, MCCs and outgoing
feeders of 415V switchgear having ACBs shall be provided with
Microprocessor based numerical relays.
04.08.02 Numerical relay shall have the following functions
• Protection
• Metering
• Monitoring
User Interfaces :
Less than 90kW capacity motors shall be fed by MCCB and contactors
through MCC.
More than 30kW capacity motor feeders shall be provided with 240V, 1-
phase space heater. Also ammeter shall be provided locally with display in
DCS/PLC/Plant Control System.
Each motor feeder of MCC shall be provided with suitably rated 415/110V
control transformer, for arranging control supply for the module. All the
necessary auxiliary and main contactors shall be provided suitable for this
control supply.
Control
Close & Open control of the Incomer & Buscoupler breakers and start/stop
control of all motors/outgoing feeders shall be from DCS/PLC/Plant Control
System through the interposing relays.
All Modules shall have ON, OFF & TRIP indications through LED
indication lamp
04.09.00 REQUIREMENTS FOR THE SWITCHBOARD COMPONENTS
04.09.01 Switches
Switches shall be triple/double pole, air break type and designed for duties as
specified in Annexure-B. Motor duty switches shall be capable of safely
making and breaking the locked rotor current of the associated motor circuit.
The switch shall have a quick-make, quick-break mechanism operated by a
suitable external handle, complete with position indicator. This handle shall
have provision for padlocking in ON and OFF position.
The compartment door shall be interlocked mechanically with the switch such
that the door cannot be opened unless the switch is in OFF position. Means
shall be provided for releasing this interlock at any time.
Switches shall be capable of withstanding the let-through fault current of
back-up fuses or circuit breakers.
Wherever two incoming switches and one bus-section switch/breaker are
provided for an assembly, these shall be mechanically/key interlocked to
ensure that only two out of the three can be closed at time.
Wherever two incoming switches are provided for an assembly, these shall
be mechanically/key interlocked to ensure that one of the two can be closed
at time.
04.09.02 Fuses (as applicable)
Fuses shall be HRC, cartirdge link type, with a minimum interrupting capacity
equal to the short circuit current of the LT system.
Fuses shall be furnished complete with fuse bases and fittings of such design
as to permit easy and safe replacement of fuse element.
Visible indication shall be provided on blowing of the fuse.
Motor fuse characteristics and ratings shall be chosen to ride over starting
period without blowing. The fuse on incoming feeder wherever provided, shall
be chosen to provide discrimination with motor/feeder fuses.
04.09.03 Meters and Meter Selector Switches
All indicating instruments (96 x 96 mm) shall be flush mounted on panel front,
with 90 Deg. scale, anti-glare glass and accuracy class of 1. Each meter shall
have zero adjuster on the front.
Where Numerical Relays are not envisaged, Ammeters shall be provided for
motor feeders of rating above 30 KW. Motor ammeters shall have an extended
suppressed end-scale range to indicate starting current (6 to 8 times full-load
current).
Meter selector switches shall be maintained contact, stay-put type, with knob
handle. Ammeter and voltmeter selector switches shall be four position type.
Ammeter selector switches shall have made before break contacts, to prevent
open circuiting of CT secondary.
Incomers, Bus PT & Line PT shall have Ammeters & Voltmeters (as
applicable) with selector switches in addition to metering in Numerical
Relays. Metering for all other feeders shall be through Numerical Relays.
04.09.04 Transducer( Wherever Numerical relays are not envisaged)
Feeders requiring remote metering and/or current monitoring shall be
provided with solid state current transducers with calibration for full scale
reading. The dual output shall be 4-20 mA DC of which shall correspond to
the normal range. Transducers shall be duplex type.
04.09.05 Thermal Overload
a) Thermal overload relays shall be three element, positive acting, ambient
temperature compensated with adjustable settings.
b) Single phasing preventor shall be provided as an inbuilt feature of the thermal
overload relay.
c) Relays shall be manual reset type with changeover contacts, Resetting of
relays shall be possible with compartment door closed. Colour of the
resetting button shall be BLACK.
d) Relays may be direct acting or C.T. operated, depending on current rating.
C.T.s shall be included in the scope of supply. C.T. operated relays shall be
used for L.T. Motors having rating 45 KW and above.
e) Relays for fan motors having long starting time shall be saturable case C.T
operated.
04.09.06 Secondary Wiring
All boards shall be fully wired at the factory to ensure proper functioning of
control, protection, transfer and interlocking schemes.
Fuse and links shall be provided to permit individual circuit isolation from bus
wires without disturbing other circuits. All spare contacts of relays, switches
and other devices shall be wired up to terminal blocks.
Wiring shall be done with flexible, 660 V grade, PVC insulated switchboard
wires with stranded copper conductors of 2.5 mm2 for current and voltage
circuits and 1.5 sq.mm for other circuits..
Each wire shall be ferruled by plastic tube with indelliable ink print at both end
having terminal block no., terminal nos, destination no. as per approved
Drawing.
Wire terminations shall be made with crimping type connectors with solderless
insulating sleeves. Wires shall not be spliced between terminals.
04.09.07 Terminal Blocks
Terminal blocks shall be 650V grade clip-on type with marking strips.
Terminals for C.T. secondary leads shall have provision for shorting.
Terminal blocks used for interface with PLC / Plant Control System via
termination cabinet shall be suitably sized to facilitate proper termination of
interconnecting cables.
Not more than two wires shall be connected to any terminal. Spare terminals
equal in number to 20% active terminals shall be furnished.
Terminal blocks shall be located to allow easy access. Wiring shall be so
arranged that individual wires of an external cable can be connected to
consecutive terminals.
04.09.08 Cable Termination
Generally, all assemblies shall be designed for cable entry from the bottom.
Sufficient space shall be provided for all the cables as per cable schedule, for
ease of termination and connection.
All provisions and accessories shall be furnished for termination and
connection of cables as per cable schedule, including removable gland plates,
cable support, crimp type tinned copper lugs, double compression brass glands
with tapered washer (Power cable only) and terminal blocks.
Gland plates shall be minimum 3 mm thick. The gland plate and supporting
arrangement for single core power cables shall be non-magnetic type to
minimise the flow of eddy current.
Vol. – IV ELECTRICAL SYSTEM Page 58 of 152
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METTUR THERMAL POWER STATION - I (4X210MW)
Protections Metering
• Over current protection Current on all the 3 phases
• Earth fault protection Voltage – phase to phase, phase to neutral
• Under voltage KW
• REF protection (For incomers kWhr
through transformers)
• Synchronising check relay
(b) Buscouplers :
Protections Metering
• Over current protection Current on all the 3 phases
Earth fault protection KW
Synchronising check relay
Protections Metering
• Composite motor protection Current
to cover a minimum of Voltage
protections such as over kW
current, short circuit, earth KWh
fault, locked rotor, Negative
phase sequence, thermal
alarm etc.(for large
motors>=90kW
(ii) The minimum protections/metering required for the following feeders shall include, but
not limited to:
(a) Bus PT /Line PT Modules
Protections Metering
• Under voltage protection Voltage – phase to phase, phase to neutral
• Fuse failure protection
Protections Metering
• Bimetallic Thermal Overload Phase current (for motors of rating above
relay (with single phase 15kW)
preventor), short circuit
protection (MCCB)
Protections Metering
• Short circuit protection (if Phase Current (1 phase)
MCCB )
Protections Metering
• Short circuit protection Phase Current (1 phase) for modules rated
(MCCB ) 63A and above.
415V Switchgears/MCC/Boards
1. Service : Indoor
2. Type : Air – break
3. Rated service voltage : 415 v + 10%
4. Rated Current : As per requirement
5. Rated frequency : 50 Hz + 5%
6. System earthing : NGR grounded
7. Rated short time withstand : 50 KA (r.m.s.)
current for 1 sec.
8. Rated Symmetrical : 50 KA (r.m.s.)
breaking current at rated
voltage
HRC fuses
Contactor
: AC DC
1. Service : Indoor within steel Indoor within
cubicle for steel cubicle
maximum system for maximum
voltage, starting of system voltage,
motors and starting of
miscellaneous motors and
loads. miscellaneous
loads.
2. No. of Poles : 3 2
3. Rated service voltage : 415 V + 10% 220 V (190-
240V)
4. Rated frequency : 50 Hz + 5%
5. System earthing : Solidly grounded Ungrounded
6. Short time rating : To be coordinated To be
with fuse coordinated
Preceding it. with fuse
Preceding it.
7. Continuous current : To suit motor To suit motor
continuous current continuous
rating Conditions current rating
specified. Conditions
specified.
8. Short circuit level : 50 KA (rms) at 415 20 KA at 220V
V
9. Control circuit : 110V ±10% 1-ph 220V tapped
50 Hz ± 5% from power
derived from circuit.
415/110V control
transformer to be
provided in each
cubicle. In
addition, One
number Control
Transformer in
each bus section
shall be provided
for Testing
Current Transformer
1. Service : Indoor
2. System : 415V, 3 phase, 3 wire, 50Hz, Solidly
earthed neutral
3. Type : Resin cast
4. Rated voltage : 415 V +10%
5. Quantity required : As per requirements of individual
feeders and as mentioned in the
specification drawings.
6. Ratio and burden : As required, C.T. secondary rating
shall be 1 Amp.
7. Accuracy : 5P10 or better for protection and
class-1 for metering.
8. Power frequency withstand : 2.5 KV (r.m.s) for one minute
voltage
9. Rated short time current :
Short time withstand : 50 KA (r.m.s)
current for 1 sec
Vol. – IV ELECTRICAL SYSTEM Page 70 of 152
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METTUR THERMAL POWER STATION - I (4X210MW)
Potential Transformer
1. Service : Indoor
2. System : 451V, 3 phase, 4 wire, 50 Hz, Solidly
earthed neutral
3. Type : Cast resin
4. Rating- Voltage ratio : 415/√3 / 110/√3
5. Rated burden : As specified
6. Accuracy class : As per requirement
7. Power frequency withstand : Primary: 3.0 KV for one minute
voltage Secondary : 2.0 KV for one minute
8. Mounting : Fixed type
9. Quantity : As per requirement
Numerical Relays
The numerical relays for 0.415KV Switchgears shall comply with but not limited to the
following technical requirements.
Annexure – A
Selection of Switches & contactors
Motor Feeders
Type Motor Rating Switch Fuse Contactor Cable size
Rating / MCCB
A 0 - 5.5 KW 32A 16A 3/c – 2.5 Sq.mm - Cu
B 5.6 - 11 KW 63A 32A 3/c - 16 Sq.mm - Al
C 11.1 - 22 KW 63A 63A 3/c - 35 Sq.mm - Al
D 22.1 - 50 KW 100A 100A 3/c - 95 Sq.mm - Al
E 50.1 - 75 KW 200A 160A 3/c - 185 Sq.mm - Al
F 75.1 - 89 KW 400A 300A 2x3/c - 185 Sq.mm - Al
NOTE :
1. Rating of MCCBs, thermal overload relay and Contactors are to be coordinated
with motor rating by the bidder.
2. MCCBs with E/F protection to be considered for motors above 45 KW.
Outgoing Feeders
Type Switch Fuse Rating / MCCB Cable Size
AF 32A 4/c – 16 Sq.mm – Al
BF 63A 4/c – 35 Sq.mm – Al
CF 100A 3.1/2c – 95 Sq.mm – Al
DF 200A 3.1/2c – 300 Sq.mm – Al
EF 400A 4 x 1/c – 630 Sq.mm – Al
FF 630A 7 x 1/c – 630 Sq.mm – Al
Note: Selection of switches, contactors and cable sizes indicated above are for general
guidance of the bidder and the exact requirement shall be as per the detail engineering by
bidder.
3.01.04 Motors open to the atmosphere shall be protected with rain canopy. Rain canopy
provided for the HT motors shall be removable type in order to enable handling
of these motors by using the hoists provided for the purpose.
3.01.05 All motors shall be provided with jacking bolts with its foundation frame for
alignment.
3.01.06 All HT motors shall have individual dedicated electrically operated hoists for
maintenance of motors. Control panels for the Crane/hoist shall be located at
the ground level for ease of maintenance.
4.00.00 Type and rating
4.01.00 A.C. Motors
4.01.01 Motors shall be general purpose, constant speed, squirrel cage, three phase /
single phase, induction type.
4.01.02 All motors shall be rated for continuous duty (S1) unless stated otherwise.
4.01.03 The motor name-plate rating at 50°C shall have at least 10% margin for HT
and 15% margin for LT system over the input power requirement of the driven
equipment at rated duty point and also covering the 10% margin on maximum
load demand of the driven equipment under entire operating range, including
voltage and frequency variations, unless stated otherwise in driven equipment
specification or in general electrical specification. For S4 duty motors 10%
margin on maximum load demand of the driven equipment shall be
considered.
4.01.04 The motor characteristics shall match the requirements of the driven equipment
so that adequate starting, accelerating, pull up, break down and full load torques
are available for the intended service.
4.01.05 Frequent starting HT motors shall be fed through vacuum contactors and fuses.
4.01.07 Motors up to 160KW shall be LT (415V). Motors above 160KW shall be of 6.6
KV voltage rating.
4.01.08 All motors shall be supplied with foundation bolts (if applicable), drain holes
with plugs.
4.01.09 Motors in the explosion hazardous areas shall be explosion proof.
4.02.00 D.C. Motors
4.02.01 D.C. motor provided for emergency service shall be shunt/compound wound
type and rated for 220V DC.
4.02.02 Motor shall be sized for operation with fixed resistance starter for maximum
reliability. Starter panel complete with all accessories shall be included in the
scope of supply of the bidder.
5.00.00 Performance
Vol. – IV ELECTRICAL SYSTEM Page 75 of 152
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METTUR THERMAL POWER STATION - I (4X210MW)
5.04.01 The locked rotor withstand time under hot condition at 110% rated voltage
shall be more than motor starting time by at least 2.5 seconds for motors
upto 20 seconds starting time and by 5 seconds for motor with more than
20 seconds starting time.
To prevent unwanted tripping of a high inertia load at start-up, there may be
need to shunt out the motor’s overload trip device. Speed switches mounted
on the motor shaft may be provided in such case. Heating experienced during
start-up must still be considered when sizing the motor
Hot thermal withstand curve shall have a margin of at least 10% over the full
load current of the motor to permit relay setting utilizing motor rated
capacity
Accelerating torque at any speed with the lowest permissible starting voltage
shall be at least 10% motor full load torque.
Pull out torque at rated voltage shall not be less than 205% of full load torque
5.04.02 H.T Motors Starting time mentioned above is at minimum permissible
voltage of 80% rated voltage.
5.04.03 Hot thermal withstand curve shall have a margin of at least 10% over the
full load current of the motor to permit relay setting utilising motor rated
capacity.
6.00.00 Specific Requirements
6.01.00 Enclosure
6.01.01 All H.T & L.T motor enclosures shall conform to the degree of protection
IP-55 for outdoor & indoor unless otherwise specified. Motor for outdoor
or semi-outdoor service shall be of weather-proof construction.
6.01.02 For hazardous area approved type of increased safety enclosure shall be
furnished.
6.02.00 Cooling
6.02.01 The motor shall be self ventilated type, either totally enclosed fan cooled
(TEFC) or closed air circuit air- cooled (CACA).
6.02.02 For large capacity motors, closed air circuit water cooled (CACW) may be
considered for acceptance.
6.03.00 Winding and Insulation
6.03.01 All insulated winding shall be of copper.
6.03.02 HT and LT motors shall have class F insulation but temperature rise shall be
limited to class B (as measured by resistance method).
6.03.03 Windings shall be impregnated to make them non-hygroscopic and oil resistant.
6.04.00 Tropical Protection
Vol. – IV ELECTRICAL SYSTEM Page 77 of 152
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6.04.01 All motors shall have fungus protection involving special treatment of
insulation and metal against fungus, insects and corrosion.
6.04.02 All fittings and hardware shall be corrosion resistant.
6.05.00 Winding & Insulation
: Non-hygroscopic, oil resistant, flame resistant copper windings
motors : Thermal class 155 (F) insulation, Temperature rise shall be limited to
Class B. Winding material shall be of copper. The winding insulation
process shall be total Vacuum Pressure Impregnated i.e resin poor method.
The lightning impulse & interturn insulation surge withstand level shall be
as per IEC-60034 part-15
415VAC & 220V DC motors : Thermal Class(F )
6.06.00 Bearings
6.06.01 Motor shall be provided with antifriction bearings, unless sleeve bearings are
required by the motor application.
6.06.02 Vertical shaft motors shall be provided with thrust and guide bearings. Thrust
bearing of tilting pad type is preferred.
6.06.03 Bearings shall be provided with seals to prevent leakage of lubricant or
entrance of foreign matters like dirt, water etc. into the bearing area.
6.06.04 Sleeve bearings shall be split type, ring oiled, with permanently aligned, close
running shaft sleeves.
6.06.05 Grease lubricated bearings shall be pre-lubricated and shall have provisions for
in-service positive lubrication with drains to guard against over lubrication.
6.06.06 Oiled bearing shall have an integral self cooled oil reservoir with oil
ring inspection ports, oil sight glass with oil level marked for standstill and
running conditions and oil fill and drain plugs.
6.06.07 Forced lubricated or water cooled bearing shall not be used without prior
approval of Owner.
Greased ball, roller and /or sleeve bearing shall be rated for minimum standard
life of 40,000 hours taking bearing and driven equipment loads in to account.
6.06.08 Lubricant shall not deteriorate under all service conditions. The lubricant shall
be limited to normally available types with IOC equivalent.
6.06.09 Bearings of HV motors rated 1000 KW and above shall be insulated as
required to prevent shaft current and resultant bearing damage.
6.07.00 Noise & Vibration
6.07.01 The noise level shall not exceed 85 db (A) at 1.5 meters from the motor.
6.07.02 The peak amplitude of the vibration shall be within IS specified limits.
Vol. – IV ELECTRICAL SYSTEM Page 78 of 152
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7.02.01 Motor of rating 30 KW and above shall be provided with space heaters, suitably
located for easy removal or replacement.
7.02.02 The space heater shall be rated 240 V, 1 phase 50 Hz and sized to maintain the
motor internal temperature above dew point when the motor is idle. Heaters to
be automatically OFF when the motor is switched ON.
7.03.00 Temperature Detectors :
7.03.01 In HT motors, at least four numbers simplex / two numbers duplex platinum
resistance type temperature detectors shall be provided in each phase stator
winding.
7.03.02 Each bearing of HT motor shall be provided with dial type thermometer with
adjustable alarm contact and 1 no. duplex platinum resistance type temperature
detectors.
7.03.03 The temperature detector mentioned above shall be resistance type, 3 wire,
platinum wound, 100 ohms at 0 Deg.C.
7.03.04 Leads of all duplex type motor winding RTDs and motor bearing RTDs shall be
wired up to respective switchgear metering & protection compartment. From
which one set of RTDS shall be connected to numerical protection relay and
another set shall be kept free for PLC / Plant Control System connectivity.
7.04.00 Vibration monitor :
All HV motors shall be provided with vibration pads for mounting vibration
detectors. Vibration monitors shall be provided for all HT motors and shall be
suitably connected to the PLC / Control System of the Plant.
7.05.00 Indicator/Switch :
7.05.01 Dial type local indicator with alarm contacts shall be provided for the following :
a) Hot and cold air temperature of the closed air circuit for CACA and CACW
motor.
7.05.02 Flow switches shall be provided for monitoring cooling water flow of CACW
motor and oil flow of forced lubrication bearing, if used.
7.05.03 Alarm switch contact rating shall be minimum 0.5 A at 220V D.C. and 5A at
240V A.C.
7.06.00 Current Transformer for Differential Protection :
7.06.01 Motors of rating 1000 kW and above shall be provided with differential
protection. Matching CTs shall be provided by the bidder for the same. The 3
nos. current transformers, one for each phase shall be mounted in a separate
compartment in the neutral side terminal box. The three phases shall be
connected to form the star point after they pass through the CTs. The CTs shall
be of relay accuracy and CT characteristics shall be compatible with the
differential relay . The additional 3 nos. CTs of identical characteristics shall be
Vol. – IV ELECTRICAL SYSTEM Page 81 of 152
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In addition, any special test called for in the driven equipment specification
shall be performed for all motors.
9.00.00 Drawings, Data & Manuals
9.01.00 Drawings, data & manuals for the motors shall be submitted as indicated below
List of the motors
Individual motor data sheet as per format of the proposal data sheets.
Scheme & write up on forced lubrication system, if any
Type test report
9.02.00 After award of the Contract
a) Dimensional General Arrangement drawing
b) Foundation Plan & Loading
c) Cable end box details
d) Space requirement for rotor removal
e) Thermal withstand curves hot & cold
f) Starting and speed torque characteristics at 80% & 100% voltage
g) Complete motor datasheet
h) Erection & Maintenance Manual
i) Test reports
j) QAP
1.00.00 Scope
1.01.00 This Section covers the general requirements of Electric Motor
Actuators for valves, dampers and gates.
1.02.00 All electric motor integral type actuators shall be furnished in accordance
with this general specification and the accompanying driven equipment specification.
2.00.00 Standards
2.01.00 All electrical equipment shall conform to the latest applicable IS, ANSI
and NEMA Standards, except when stated otherwise herein or in driven equipment
specification.
2.02.00 Major standards, which shall be followed, are listed below. Other
applicable Indian Standards for any component part even if not covered in the listed
standards shall also be followed
i) IS-9334
ii) IS-12615
iii) IEC:60034
3.00.00 Service Conditions
3.01.00 The actuator shall be suitable for operation in hot, humid and
tropical atmosphere, highly polluted at places with coal dust and/or fly ash.
3.02.00 Unless otherwise noted, electrical equipment/system design shall be based
on the service conditions and auxiliary power supply given in chapter-1.
4.00.00 Rating
4.01.00 For isolating service, the actuator shall be rated for three successive open-
close operation of the valve/damper or 15 minutes, whichever is longer.
4.02.00 For regulating service, the actuator shall be suitably time-rated for the duty
cycle S4 - 600 cycles or better.
5.00.00 Performance
The actuator shall meet the following performance requirements:
5.01.00 Open and close the valve or damper completely and make leak-tight valve
closure without jamming.
5.02.00 Attain full speed operation before valve load is encountered and impart an
unseating blow to start the valve in motion (hammer blow effect).
5.03.00 Operate the valve stem at standard stem speed and shall function against
design differential pressure across the valve seat.
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5.04.00 The motor reduction gearing shall be sufficient to lock the shaft when the
motor is de-energised and prevent drift from torque switch spring pressure.
5.05.00 The entire mechanism shall withstand shock resulting from closing with
improper setting of limit switches or from lodging of foreign matter under the valve seat.
6.00.00 Specific Requirement
6.01.00 Construction :
6.01.01 The integral actuator shall essentially comprise the drive motor, torque/ limit
switches, gear train, clutch, hand wheel, position indicator/ transmitter, in-built close / open
contactors, thermostat for over load protection, space heater and internal wiring.
6.01.02 The actuator enclosure shall be totally enclosed, dust tight, weather-proof
suitable for outdoor use without necessity of any canopy.
6.01.03 All electrical equipment, accessories and wiring shall be provided with
tropical finish to prevent fungus growth.
6.01.04 The actuator shall be designed for mounting in any position without any
lubricant leakage or operating difficulty.
6.02.00 Motor :
6.02.01 The drive motor shall be three phase, squirrel cage, induction machine with
minimum class F insulation having temperature rise limited to Class-B.and designed for
high torque and reversing service. Enclosure shall be IP—67 or better.
6.02.02 The motor shall be designed for full voltage direct on-line start, with starting
current limited to 6 times full-load current.
The motor bearing shall be double shielded, grease lubricated and antifriction type.
6.02.03 The motor shall be capable of starting at 85 percent of rated voltage and
running at 80 percent of rated voltage at rated torque and 85 percent rated voltage at 33
percent excess rated torque for a period of 5 minutes each.
6.02.04 Earthing terminals shall be provided on either side of the motor.
6.03.00 Limit Switches :
Each actuator shall be provided with following limit switches: -
6.03.01 2 torque limit switches, one for each direction of travel, self-locking,
adjustable torque type.
6.03.02 4 end-of-travel limit switches, two for each direction of travel.
6.03.03 2 position limit switches, one for each direction of travel, each adjustable at
any position from fully open to fully closed positions of the valve/damper (wherever
applicable).
6.03.04 Each limit switch shall have 2 NO + 2 NC potential free contacts. Contact
rating shall be 5A at 240V A.C. or 0.5A at 220V D.C.
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7.00.00 Interfaces:
i) Open/Close command termination logic with position & torque Limit Switches,
positioner circuit shall be suitably built in the PCB inside the actuator
ii) For Binary Drive (both ON-OFF and Inching type) :- Open/Close command & status
thereof and disturbance monitoring signal (common contact for Overload, Thermostat,
control supply failure, L/R selector switch at local & other protections operated) shall be
provided.
iii) Interface with the control system shall be through hardwired signal only. Inter posing
relays provided in the actuator shall be energized to initiate opening and closing, by 24V DC
signal from the external control system.
iv) For Modulating drive: - the command to actuator shall be in form of 4-20mA signal.
The necessary positioning circuit and motor protection shall be provided.
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1.02.00 UPS System shall be adequately designed to cater the entire UPS loads of each
system / sub system.
Note: 10% cushion to be kept in UPS system/set and UPS-DB for Purchaser’s
future use.
2.02.00 Annexures
2.02.01 All annexures appended to this specification shall form part of this specification and
supplement the requirements specified herein.
2.02.02 This specification shall be read and construed in conjunction with the drawings and
annexures to determine the scope of work and terminal points.
2.03.00 Completeness of supply
2.03.01 It is not the intent to specify completely herein all details of the equipment.
Nevertheless, the equipment shall be complete an operative in all aspects and shall
conform to the highest standard of engineering, design and workmanship.
2.03.02 Any material or accessory which may not have been specifically mentioned but
which is necessary or usual for satisfactory and trouble free operation and
maintenance of the equipment shall be furnished.
2.03.03 The bidder shall supply all brand new equipment and accessories as specified herein.
2.04.00 Guaranteed Performance
2.04.01 The proposal data sheets given in another volume of this package specification shall
be filled in without any ambiguity by typing in appropriate place on each page.
2.05.01 Before starting manufacture of any equipment, the bidder shall have to take approval
of relevant drawings and data from Owner/Consultant in writing.
2.05.02 Any manufacture done prior to the approval of drawings/data shall be rectified in
accordance with the approved drawings/data by the bidder at his own cost and the
equipment shall be supplied within the stipulated period.
b) The UPS system excluding its battery shall be installed indoors in A.C. environment.
DC supply to Inverter shall be provided from Common Battery System / DCDB
c) UPS system shall be compatible for satisfactory and well-coordinated operation with
other related equipment as well as with input and output systems.
d) Energizing or de-energizing any portion of the system serviced by the UPS shall not
cause output changes which shall affect the operation or integrity of the remaining
portions of the system in any way.
e) The equipment shall be self-protecting against all A.C. and D.C. transients, voltage
surges, and steady state abnormal voltages and currents.
f) The circuit protection shall be coordinated with UPS short circuit capacity and
protective device characteristics so that a fault on any circuit shall result in minimum
loss of function.
g) All non-interrupting components of UPS system shall be capable of withstanding the
prevailing short circuit current without damage.
h) All circuit interrupting components shall be capable of withstanding and interrupting
the prevailing short circuit currents without damage.
i) For continuous operation at specified ratings, temperature rise of the various
components of UPS system shall be limited to the permissible values stipulated in
the relevant standards and/or this specification.
k) The inverters, static switches, regulating transformers and voltage stabilizers should
be arranged in such a way that any equipment shall be fully isolated for maintenance
without affecting in any way the operation of other panels/ components.
l) In the A.C. Distribution Board, the bidder shall provide 10% or minimum one (1)
no. spare feeder of each size and type of the outgoing feeders.
m) The UPS system supplied shall have provision to transfer UPS parameter/data to
PLC/Control System. Necessary data transfer software & hardware shall be
incorporated in the system for this.
a) 2 (Two) nos. of independent A.C. power sources will be available to the UPS
system. The system is so designed that its load shall be served without
interruption as long as one of the above power sources is available within
specified limit of voltage and/or frequency.
The UPS shall consist of two physically separate sets of equipment streams
consisting of the following :
i) Two sets of Rectifier Charger Sets with Battery Banks, Two sets of inverters
to produce high quality 240V, 1Ph 50 Hz A.C. output power.
ii) Two sets of static switches, synchronizing circuit to parallel the above-
mentioned Inverter output and bypass stabilized power stream.
v) One set of standby bypass stream consisting of suitable transformers, Static
voltage regulator etc. to produce regulated 240V, 1 Ph. 50 Hz A.C. power
from the 415V, 3 Ph. 50 Hz A.C. input from FGD LT supply.
vi) One UPS A.C. power distribution board with suitable no. of outgoing
feeders.
Two sets of equipment streams as mentioned above shall constitute the UPS
system.
One set of synchronizing equipment and high performance static switch shall
parallel the above two streams and common output shall be taken to loads
which can accept only single non-redundant power input source.
The system shall ensure highest system availability around 99%.
b) Each of the two UPS streams shall be of 100% capacity and shall normally
work, each sharing 50% load. On failure of any stream, its load gets
automatically transferred to the other inverter through static transfer switch.
c) If one UPS stream is out of service for any reason then the second UPS
stream shall be working with 100% UPS load.
d) Inside each stream on failure of its inverter assembly the standby DC source
shall back up to supply the 100% UPS load automatically through static
transfer switch.
a) The static inverters shall be static type consisting of IGBT PWM type
inverter, static filters, integrated control modules including necessary
oscillators, voltage regulators, current limiting and surge suppression.
b) The inverter equipment shall include all necessary circuitry and devices to
conform requirements like voltage regulation, soft start, transient recovery,
protection, automatic synchronisation, wave shaping etc. as specified herein.
c) Upon transfer of full load, the inverter output voltage shall not drop below
80% of nominal voltage during the first half cycle after transfer and 90% of
nominal voltage in the next half cycle. The recovery to within ± 2% of
voltage shall be in less than 50 milli-seconds.
Vol. – IV ELECTRICAL SYSTEM Page 91 of 152
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a) Inverter equipment shall include stable solid state oscillator devices designed
to automatically maintain the inverter output in phase and in synchronism
with the standby A.C. source.
b) Facility shall be provided for automatic transfer to internal oscillator
operation when the standby source frequency is beyond specified limits and
the frequency shall be automatically controlled within 50 Hz plus or minus
0.5 Hz when the inverter operates in this mode.
c) Retransfer to standby A.C. source for synchronisation shall be automatic
after the standby source frequency is restored to permissible limits and
remains within this limit for an adjustable time delay period (up to 5
seconds).
d) Provision shall be made for stepless adjustment of synch- disconnect
frequency range from 50 Hz ± 0.5 Hz to 50 Hz ± 2 Hz.
e) Automatic adjustment of phase relationship between inverter output and
stand-by A.C. source shall be gradual at a controlled slow rate, which shall
not exceed one hertz per second.
a) The static transfer switch shall be solid-state type using SCR for
automatic/manual transfer of load from "inverter" to "stand-by" source and
vice-versa.
h) Transfer Inhibit
Automatic or manual transfer from inverter to stand-by A.C. source vice
versa shall be inhibited when the inverter frequency is not synchronised to
the alternate source.
i) Retransfer to Normal
i) The return to inverter mode shall be manual in all cases.
ii) Manual transfer shall be initiated by push button actuation.
a) Manual by-pass switch is used to isolate any static transfer switch for
maintenance or repair without interruption to the UPS load.
b) The switch has also the facility of by-passing both the static transfer switches
during start-up at the option of the operator.
a) The DB shall have one section with MCCB as incomer and shall have bus
healthy lamps, volt meter and ammeters. Outgoing feeders to the loads shall
be protected by semiconductor fuses with fuse monitoring devices, MCCBs
and feeder ‘ON’ LED indication with glass fuse. Each load shall be fed by
two independent feeders terminated into a change over switch at the load
point. The gland plate of the distribution board shall be non-magnetic type
having thickness 3mm.
Interposing relays / transducers /potential free contacts required for DDCMIS
system shall be mounted on the UPS distribution board.
b) The distribution boards shall be fixed type, of modular design in freestanding
gasketted sheet steel enclosure conforming to IP-54. Sheet steel thickness
shall be 2 mm minimum.
c)Each module shall be housed in a separate compartment complete with individual
front access door. Working height shall be limited to 1800 mm from floor
level.
d) A full height vertical cable alley shall be provided in each panel to facilitate
module wiring. The alley shall be liberally sized and shall have removable
cover at the front. Removable back covers shall be provided at the back of
the panels.
e) Switches shall be double pole, air break, heavy duty type, capable of safely
making and breaking the full load current of associate circuit.
d) Each time a window lights up a master relay shall get energized to provide
group alarm signals for remote PLC/Control System alarm system.
e) The requirements of indication/metering/alarms are given in the annexure -B
f) Alarm contacts shall be rated 0.5 A at 220 V DC and 5A at 240 V A.C.
g) Electrically independent, potential free alarm contacts for each of the points
mentioned in Annexure-B shall be wired up to the terminal block for
Purchaser's use.
3.09.00 Lamp / Space Heaters / Receptacles
a) The panels shall be provided with :
i) Internal illumination lamp with door switch.
ii) Space heater with thermostat control.
iii) 3-pin 6A receptacle with plug.
b) Lamp, heater and receptacle circuits shall have individual switch fuse units.
3.10.00 Wiring / Cabling
a) The panels shall be completely wired up. All wiring shall be done with
flexible, 1100V grade, PVC insulated wires with stranded 2.5 Sq.mm copper
conductors and routed through wiring troughs. Each wire shall be ferruled by
plastic tube with indelible ink print at both end having terminal block No.,
terminal number as per approved wiring diagram.
b) Panels shall have removable 3mm. gland plate for cable entry. All
incoming/outgoing cables shall be terminated in suitable terminal block.
c) Control terminal blocks shall be box-clamp type, minimum 10 Sq.mm. 20%
spare terminals shall be furnished.
3.11.00 Nameplate
a) Engraved nameplates shall be provided for each panel and for each
equipment/device mounted on it.
b) The material shall be anodised aluminium / lamicoid, 3 mm thick, with white
letters on black background.
c) Nameplates shall be held by self-tapping screws. The size of nameplates shall
be approximately 20 mm x 75 mm for equipment and 40 mm x 150 mm for
panels.
d) Nameplates for panels shall be provided both on the front and rear.
e) Control and meter selection switches shall have integral nameplates.
Nameplates for all other devices shall be located below the respective devices.
f) Instruments and devices mounted on the face of the panels shall also be
identified on the rear with the instrument/device number. The number may be
painted on or adjacent to the instrument or device case.
g) Caution notice on suitable metal plate shall be affixed at the back of each
panel.
3.12.00 Grounding
a) Normal 3-phase A.C power supply shall be grounded at the source. For
grounding other than this, isolation transformer shall be furnished with the
U.P.S.
b) The inverter D.C. input and A.C. output shall be electrically isolated from
each other and from cabinet ground.
c) Panels shall have fully rated ground bus with two ground terminals, one at
each end.
d) Each terminal shall comprise two-bolt drilling M10 G.I. bolts and nuts to
receive Purchaser's ground connection of 50 x 6 mm G.S. flat.
e) Separate electronic grounding shall be provided for each UPS system.
a) All equipment accessories and wiring shall have fungus protection, involving
special treatment of insulation and metal against fungus insects and
corrosion.
b) Screens of corrosion resistant material shall be furnished on all ventilating
louvers to prevent the entrance of insects.
3.14.00 Painting
a) The panels shall be finished in light grey shade (shade 631 of IS-5) with two
coats of synthetic enamel paint. The panels shall have a matt finish to prevent
any glare from surface due to illumination.
4.00.00 Tests
4.01.00 All equipment and components thereof shall be subject to shop tests as per relevant
IEC/BIS Standards. The tests shall include, but shall not be limited to :
4.02.00
Tests on UPS System
a) Type & routine test for various components.
b) Burning test on PCBS - Assembled PCBS shall be tested at 70 Deg.C for 72
hours in loaded condition.
c) Rapid temperature cycling test at 70 Deg.C and 0 Deg.C for 30 minutes at
each temperature - 5 such cycles.
d) Functional tests to demonstrate compliance with all specified requirements
and published. Specifications such as frequency, regulation, voltage
regulation, current limiting, fuse clearing capability of inverters,
demonstration of phase and frequency control of inverter for synchronisation
with range of adjustments transfer and retransfer of static switches under
influence of under voltage and over current, tests on chargers, batteries and
other system component to confirm compliance with specification.
4.03.00 Type test certificates of any equipment shall be furnished, if so desired by the
Purchaser. Otherwise, the equipment shall have to be type tested, free of
charge, to prove the design.
5.02.10 Any other relevant drawing or data necessary for satisfactory installation,
operation, and maintenance.
5.03.00 The bidder may note that the drawings, data and manuals listed above are
minimum requirement only. Bidder shall ensure that all other necessary
write-ups, curves and information required to fully describe the equipment
are submitted .
The bidder shall quote any special tools and tackles needed for his
equipment or stated herein.
ANNEXURE-A
a) Nominal frequency : 50 Hz
Vol. – IV ELECTRICAL SYSTEM Page 100 of 152
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1.12.00 Rated output current at rated output voltage with current limit not operating
a) Current : 200%
b) Duration : 100 milliseconds.
2.06.00 Capacity
Vol. – IV ELECTRICAL SYSTEM Page 101 of 152
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c) Peak : 1000% of
continuous rating for 5 cycle.
2.10.00 Short time rating : Short circuit rating of the inverter for 1
second and 150% of Full load current for 2
minutes.
3.04.00 Short time rating : Short circuit rating of the inverter for 1
second and 150% of Full load current for 2 minutes.
b) Indicating meters
Tripping breakers.
Starting current of all automatically started DC drives.
Solenoid valves.
Vol. – IV ELECTRICAL SYSTEM Page 105 of 152
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Indicating lamps, Protective relays, Auxiliary relays on switchgears and control panels
Emergency lighting
Supplies to UPS Inverters
The sizing of the lead acid with plante batteries shall be as per IEEE-485. Following Factors
to be considered for Battery Sizing:
Design Margin: 1.15
Aging Factor: 1.0
The No. of cells, end cell voltage shall be considered based on the minimum and maximum
voltage windows and cable drop etc. as per system requirement.
DC scheme shall ensure that each critical consumer is fed from two different bus sections.
DCDBs shall be provided with adequate number of feeders on each section.
3.01.07 Ampere hour capacity (minimum) shall be as specified in Technical
particulars for design for 10 hours discharge rate with final voltage per cell
1.85V.
For faster discharge rate, the permissible continuous load with final
discharge voltage 1.85V / Cell shall be based on the following :
Discharge Time AH capacity in % of rated 10 Hr. capacity
10 hrs.
3.01.08 While estimating battery capacities, an ageing factor of 1.0 may be kept as per
IEEE -485 guidelines.
3.01.09 Additionally, 5% margin to be kept for future use.
3.01.10 For the purpose of estimating battery capacities and to arrive the
temperature compensation , the maximum and minimum temperatures shall
be considered as 50 Deg.C and 5 Deg.C respectively.
4.02.00 Battery
4.02.01 General
a) The battery shall be Plante type
b) The plates shall be designed for maximum durability during all service
conditions including high rate of discharge and rapid fluctuation of load.
4.02.02 Construction
a) Each cell shall be assembled in sealed type, heat resistant, shock
absorbing, robust, clear view SAN container.
b) Electrolyte level shall be marked on the clear view container or
level indicators as applicable. The markings shall be for upper and
lower limits.
c) Sufficient sediment space shall be provided so that the cells shall
not have to be cleaned out during normal life.
d) Vent plugs for sealed in type cells shall be anti-splash type.
e) Separator between plates shall permit free flow of electrolyte.
Separator shall be wood or other acid resisting material. Proper
arrangement to keep end plates in position shall be furnished.
f) The cells shall be supported on porcelain insulator (if required) fixed
on to the rack with adequate clearance between adjacent cells.
g) The cell terminals posts shall be provided with connector bolts and
nuts, effectively coated with lead to prevent corrosion
h) Lead or lead coated copper connectors shall be furnished to connect
up cells of battery set.
i) Positive, negative and 84th tap terminal posts shall be clearly and
indelibly marked for easy identification.
j) Lead-coated bent copper plate, tubular copper lugs, teak wood
clamp,bolts, nuts, washers, etc. shall be furnished for connection of
outgoing stranded copper cables from battery to charger.
k) The battery shall be shipped uncharged with the electrolyte
furnished in a separate non-returnable container.10% extra electrolyte
shall be furnished to cover spillage in transit or during erection.
4.02.03 Racks
a) The racks for supporting battery cells shall be constructed of best
quality teakwood with acid resistant insulation between the cells and
the rack and shall be painted with at least three (3) coats of anti-acid
paint, the shade of which shall be subject to approval of the Purchaser.
following meters :
i) One (1) D.C. ammeter (for charger output)
ii) One (1) D.C. voltmeter with selector switch (for charger
output/battery voltage)
iii) Necessary shunts for local and remote metering shall be provided.
iv) Measurement for AC input voltage and current (through
Voltmeter/Ammeter selector switch).
c) Each central panel shall be provided with the following :
i) One (1) D.C. ammeter (for load circuit)
ii) One (1) A.C. voltmeter with selector switch (for main
A.C.supply)
iii) One moving coil center zero ammeter, with shunt to read
discharge/charge current of the battery, with suitable range .
Battery trickle charging current(through amplifier)
DC bus voltage (through selector switches) to measure between positive
to earth, negative to earth and positive to negative.
4.03.06 Controls
The following manual controls shall be provided on the front of each
charger panel :
a) Selection of float, equalising, or boost charge.
b) Voltage setters for setting the output of float/equalising/ boost charge.
Setting shall be independent of each other so that setting of one voltage shall
not require resetting of the others.
c) Current limit setter.
d) Acknowledge-Reset-Test push buttons for annunciation system. The
colour of reset buttons shall be BLACK.
4.03.07 Lamp/Space heaters/receptacles
a) The charger panels shall be provided with :
i) Internal illumination lamp with door switch
ii) Space heater with thermostat control
iii) 3 pin 5A receptacle with plug
iv) Communication plug
b) Lamp, heater and receptacle circuits shall have individual switch fuse
units/MCCB.
Vol. – IV ELECTRICAL SYSTEM Page 112 of 152
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METTUR THERMAL POWER STATION - I (4X210MW)
4.03.08 Wiring/Cabling
a) The panels shall be completely wired-up. All wiring shall be
routed through wiring troughs. Wires shall be ferruled at both ends for
identification.
b) Internal wiring of the panels shall be done with 1100 V grade PVC
insulated cables with stranded copper conductor of minimum size 1.5 Sq.
mm.
c) Panels shall have removable gland plates at the bottom for cable entry.
All incoming/outgoing cables shall be terminated in suitable terminal
blocks.
d) Control terminal blocks shall be box-clamp type, minimum 10
Sq.mm. 20% spare terminals shall be provided.
4.03.09 Grounding
a) The charger panels shall have fully rated ground bus with two ground
terminals, one at each end.
b) Each terminal shall comprise two-bolt drilling with M10 G.I. bolts
and nuts to receive Purchaser’s ground connection of 50 x 6 mm GI.
4.03.10 Tropical protection
a) All equipment accessories and wiring shall have fungus protection,
involving special treatment of insulation and metal against fungus,
insects and corrosion.
b) Screens of corrosion resistant material shall be furnished on all
ventilating louvers to prevent entry of insects.
4.03.11 Painting
The panel shall be chemically cleaned,phosphated and sprayed with two
coats of high quality premier and stoved after each coat.The panels shall be
finished in light grey shade (shade 631 of IS-5) with two coats of synthetic
enamel paint. The panels shall have a matt finish to prevent any glare from
surface due to illumination. Inside panels painting shall be as per IS-5 (shage
632 of IS-5).
4.03.12 Name Plate
a) Nameplates shall be provided for each panel and for each
equipment/device mounted on it.
b) The material shall be anodised aluminium/lamicoid, 3 mm thick,
with white letters on black background.
c) Nameplates shall be held by self-tapping screws. The size of
nameplates shall be approximately 20 mm x 75 mm for equipment and 40
Vol. – IV ELECTRICAL SYSTEM Page 113 of 152
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METTUR THERMAL POWER STATION - I (4X210MW)
ANNEXURE-A
RATINGS & REQUIREMENTS
1.0 BATTERY
1.1 Applicationl Unit battery
1.2 Ambient temperature
a) Maximum 50 Deg.C
b) Minimum 5 Deg.C
1.3 Type Lead Acid Plante
1.4 Nos. of Cells per Battery 110
1.5 Battery nominal voltage 220 V
1.6 Ten hour rating to 1.85V/Cell at 27 deg C To be decided by Bidder with
proper calculation
1.7 Proposed Method of working
a) Float charging (normal) 2.25 Volt per cell.
b) Equalising Charge (occasional) 2.36 Volt per cell
c) Boost charging 2.75 Volt per cell (maximum.)
(after complete discharge)
1.8 Intermediate tapping 84th Cell.
1.9 Mounting Teakwood
1.10 Terminal Connection 1/C, copper cables of adequate
size
2.0 BATTERY CHARGER
2.1 Charger Float charger
2.2 Type Solid-state, full wave, fully
controlled, three phase bridge.
2.3 Enclosure Sheet steel enclosure, IP-42
2.4 A.C. Input
a) Supply 415 V, 3 phase, 50 Hz, 4 wire
b) Voltage variation +/ - 10%
c) Frequency variation +/ - 5%
d) Combined volt and frequency variation 10% (absolute sum)
e) Short-circuit level 50 KA r.m.s. symmetrical.
f) System earthing Solidly earthed
2.5 Performance Requirements
a) The output voltage of the charger shall be regulated within +_ 1% of the set
value for any load variation from 0 to 100% and A.C. input voltage and
frequency variations as indicated above in 2.5.
b) The ripple content in charger D-C output shall be limited to +_ 1% of the D.C.
output voltage, at nominal A.C. voltage
2.6 Terminal Connection
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1.0 BATTERY
1.1 First charge of electrolyte plus 10% extra
1.2 Teakwood racks with 3 coats of anti-acid paint.
1.3 Stand insulators plus 5% extra
1.4 Cell insulators plus 5% extra
1.5 Cell inter-connectors with 5% extra and end take-off with one no. extra
1.6 Lead-coated connection hardware plus 5% extra
1.7 Cell numbering tags with fixing arrangements
1.8 Teakwood cable clamps with hardware.
1.9 Six (6) extra cell with all accessories but without acid.
In addition to above, each battery shall be furnished with a set of following
accessories
1.10 One (1) inter-connector bolt wrench
1.11 One (1) hydrometer syringe
1.12 One (1) thermometer with plug & cap and with specific gravity correction scale
1.13 One (1) cell testing voltmeter with leads
1.14 Pocket thermometer
1.15 Acid resisting funnels
1.16 Acid resisting jugs of adequate capacity
1.17 Rubber aprons
1.18 Rubber gloves
1.19 Cell lifting straps
1.20 PVC spill trays under the battery cells
1.21 Bridging clamps
1.22 Spanner for cells
1.23 Float type level indicator
1.24 First aid box
2.0 LIST OF ALARMS
2.1 Each Float charger and Float-cum-Boost charger panel shall be provided with one
(1) minimum twenty -point annunciation facia. Alarm points shall include
a) A.C. supply failure
b) D.C. Voltage low
c) D.C. Voltage high
d) D.C. System ground
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e) Charger overload
f) SCR fuse blown
g) Filter fuse blown
h) D.C. output fuse blown
i) Float bus over/under voltage
j) Boost bus over voltage
k) Boost over current for each charger
l) Failure of thyristor/diodes for each charger
m) Failure of blocking diodes
n) Output MCCB open for each charger
o) Battery MCCB open
All above alarms shall be duplicated to DDCMIS for operator interface at Control
Room
2.2 The central panel shall be provided with one (1) minimum eight-point
annunciation facia. Alarm points shall include :
a) Battery on boost charge
b) Float charger fail
c) Float-cum-boost charger in float mode.
d) Battery earth fault
e) Main A.C. fail
2.3 Initiating contacts, wired to two terminals, shall be provided for group
annunciation of "Battery Charger Trouble" in remote control room.
2.4 Initiating contacts for all alarm points shall also have electrically separate spare set
of contacts wired to the terminal block for future use.
2.5 All alarm contacts shall be rated 0.5A at 220V D.C. and 5 Amp. at 240V A.C.
2.6 In addition to the alarm points mentioned above, any other alarm point, if required
for battery and charger, shall be provided. In addition to above requirement, each
section of battery charger shall have at least two (2) nos. spare annunciation channels
and window facia.
3.0 LIST OF INDICATIONS
3.1 The indications to be provided on each float charger and float-cum-boost charger
panel shall include but shall not be limited to:
a) Charger power supply ON
b) Charger D.C. output healthy
c) Control supply ON
3.2 The indications to be provided on the central panel of each charger set shall
include but shall not be limited to:
a) Annunciation D.C. healthy
b) Float-cum-boost charger in equalising mode.
c) Float-cum-boost charger in boost mode
d) Float-cum-boost charger in float mode.
e) Float charger selected
f) Float charger tripped on fault
1.00.00 Scope
3.04.00 Packing
3.04.01 Cables shall be supplied in non-returnable drums. The drums shall be of heavy
construction. All wooden parts shall be manufactured from seasoned wood.
All ferrous parts used shall be treated with suitable rust preventive finish or
coating to avoid rusting during transit or storage. Wooden cable drum shall
be treated by immersing in copper-nitrate solution.
3.04.02 The ends of each length shall be sealed before shipment. Heat shrinkable cable
cap shall be used for this purpose.
3.04.03 A label shall be securely attached to each end of the reel indicating the
Purchaser's order number, Owner’s identification mark i.e. “TanGedCo”,
length, type, voltage grade, conductor size and number of cores of the
cable. A tag containing the same information shall be attached to the
leadings end of the cable inside. An arrow and necessary instructions shall be
marked on the drum indicating the direction in which it should be rolled.
Drum numbers are to be indicated on the cable drums.
3.05.00 Joints and Terminations
Materials of construction for a joint/termination shall perfectly match with
the dielectric chemical and physical characteristics of the associated cables.
The material and design concepts shall incorporate a high degree of
operating compatibility between the cable and joints. The protective
outer covering (jacket) used on the joints/terminations shall have the same
qualities as that of the cable outer sheath in terms of ambient/operating
temperature withstand capability and resistance to hazardous environments
and corrosive elements.
3.06.00 Selection Criteria
3.06.01 In cable sizing the following are to be taken into consideration.
a) Short circuit current and duration
b) Continuous current.
c) Installation conditions.
d) Voltage drop under normal running and starting condition.
3.06.02 Apart from above, consideration shall also be given to limit the cable to
some standard sizes instead of using too many types.
3.06.03 The standard cable sizes, capacities, de-rating factors, etc. as given in IS shall
be generally followed.
3.06.04 a) For breaker protected circuits minimum size shall be determined by
short circuit rating.
b) For motor circuits the selection of size shall be made ensuring that the cable
shall withstand a short circuit fault directly following a second hot start.
Vol. – IV ELECTRICAL SYSTEM Page 121 of 152
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3.06.05 For power circuits, the conductor size shall depend on full load current
subject to voltage drop not exceeding 3%. For practical purposes, the
minimum size chosen is as below :
Alu 10 Sq. mm
mini
um
Cop 2.5 Sq. mm
per
All drives of small rating where terminations with 10 Sq. mm. cables are
not feasible, shall have copper cable.
3.06.06 All control cables shall be 1.5 Sq. mm. copper cable. CT/PT cables shall be
2.5 sqmm copper cable.
3.06.07 Multi-core control cables shall generally have 20% of the total number of
cores as spare.
3.06.08 Separate cables for each type of following services / functions as applicable
shall be used for each feeder. Same multi-core cable using different services
shall not be acceptable.
a) Power.
b) Control, interlock and indication.
c) Metering and measuring.
d) Alarm and annunciation.
e) C.T. Cables.
f) V.T. Cables.
3.07.00 Cable Identification
Cable identification shall be provided by embossing the following on the
outer sheath:
a) Manufacturer's name or trade mark
b) Voltage grade
c) Year of manufacture
d) Type of insulation
e) Type of inner and outer sheath e.g. "FRLS" etc.
f) ISI marks
g) Nominal cross sectional area of the conductor & no of cores
h) Sequential marking
i) Owner’s identification mark
3.08.00 Sizes of power and control cables for guidance are given in Annexure-B.
However, the bidder shall go for detailed sizing calculation and furnish the
same.
4.00.00 Trailing Cables (Power & Control)
Trailing cables shall be as per Annexure-A.
5.00.00 Tests
5.01.00 Shop Tests
The Cables shall be subject to shop tests in accordance relevant IS/IEC
standards to prove the design and general qualities of the Cables as below: -
5.01.01 Routine tests on each drum of cables.
5.01.02 Acceptance tests on drums chosen at random for acceptance of the lot.
5.02.00 Additional Tests
Following additional acceptance tests shall also be performed on each type
of cables having outer sheath with improved fire performance (category C1,
Type FR/ Category C2, Type FRLSH)
5.02.01 Oxygen index test (for both C1 & C2)
The Oxygen index shall not be less than 29
5.02.02 Temperature Index Test (for both C1 & C2)
The measured value of temperature index shall be 21 at a temperature of
250°C
5.02.03 Flame Retardance test on single cable and on bunched cables (for both C1 &
C2)
After the test, there should be no visible damages on the test specimen
within 300mm from its upper end.
After burning has ceased, the cables should be wiped clean and the charred or
affected portion should not have reached a height exceeding 2.5 meter above
the bottom edge of the burner, measured at the front and rear of the cable
assembly.
5.02.04 Halogen acid gas evolution test (for category C2). The level of HCL evolved
shall not exceed 20 per cent by weight
5.02.05 Smoke density test (for category C2)
The cables shall meet the requirements of light transmission of minimum
40% after the test.)
Vol. – IV ELECTRICAL SYSTEM Page 123 of 152
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METTUR THERMAL POWER STATION - I (4X210MW)
ANNEXURE-A
RATINGS AND REQUIREMENTS (POWER AND CONTROL CABLE)
4.02.04 Suitable inspection opening with gaskets shall be provided for access to
support insulator, bus joints etc.
4.03.00 Bus Conductor
4.03.01 The conductor shall be of high conductivity aluminium /aluminium alloy as per
IS:5082 sized for the same rating as associated PCC / PMCC bus.
4.03.02 Joints made at the factory shall be welded type and the joints to be made at
site shall be bolted type.
4.03.03 For bolted rigid/expansion joints, necessary bolts, nuts, (cadmium plated) washers
and other hardwares shall be supplied.
4.03.04 Busbars shall be colour coded at regular intervals for easy identification. The
markings on the bars shall be Red for R-phase, Yellow for Y-phase, and Blue
for B-phase.
4.03.05 For each shipping section, the bus conductor shall be supported at
minimum two positions.
4.04.00 Bus-Bar Support
4.04.01 All buses and connections shall be supported and braced to withstand stresses
due to maximum short circuit current.
4.04.02 The bus conductor supporting insulators shall be flame retardant, non-hygroscopic,
high impact and high dielectric strength material with an anti tracking contour.
Material shall be Epoxy SMC moulded/FRP/porcelain. Spacing of the bus
support insulators shall be considered by giving due factor of safety to
withstand the forces due to the short circuit current assigned to the bus duct.
4.04.03 The insulators shall be so located that they can be easily removed and
replaced without dismantling the busduct installation.
4.04.04 Space heater shall be provided near each insulator to avoid moisture condensation
within busduct.
4.04.05 Silica gel breather shall be provided for the indoor and outdoor portions of the bus duct
for the absorption of moisture. Provision for draining moisture shall also be
provided.
4.04.06 The number and wattage of space heaters shall be decided by the Bidders.
4.05.00 Supporting Structures
4.05.01 All supporting structures required for hanging and/or supporting the complete
busduct shall be furnished. These include all members, indoor/outdoor posts,
bolts, shims, base plates, beams, hangers, brackets, bracings and hardware.
4.05.02 All buses shall be adequately supported and braced to successfully withstand
normal operation, vibration, thermal expansion, short circuit forces, and all
specified design loads.
Vol. – IV ELECTRICAL SYSTEM Page 130 of 152
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METTUR THERMAL POWER STATION - I (4X210MW)
4.05.03 All steel members shall be hot-dip galvanised after fabrication. All hardware
shall be of high strength steel with weather resistant finish.
4.05.04 For each shipping section, the enclosure shall be supported at minimum two
positions.
4.05.05 The enclosure supporting arrangement shall be such that the busduct
load is not transmitted onto the terminations.
4.05.06 Connections and Terminations
4.05.07 All matching flanges, seal-off bushings, gaskets, fittings, hardware, and
supports required for termination of the busduct at PCC, transformer, and
any other equipment shall be supplied.
All hardware used at conductor points shall be of non-magnetic, high tensile
material.
4.05.08 Expansion joints for both conductor and enclosure shall be provided as follows:
i). At all equipment terminations
ii) On either side of seal-off bushings
4.05.09 Expansion joints shall be provided on bus conductor and enclosure to take care of
thermal expansion.
4.05.10 Seal-off bushing with wall frame assembly shall be provided wherever the
busduct penetrates the building wall from outdoor to indoor.
4.05.11 Equipment terminal connection shall be readily accessible and shall provide
sufficient air gap for isolation of equipment during testing.
4.05.12 If the material of bus conductor and that of the equipment terminal
connectors are different, suitable bi-metallic connectors shall be provided.
4.06.00 Ground Bus
4.06.01 A ground bus rated to carry maximum fault current shall be provided running the
entire length of the busduct, grounding all parts of the supporting
structure and each enclosure section.
4.06.02 The ground bus shall be provided with two-bolt drilling with G.I. bolts and
nuts at each end to receive the G.S. earthing flats. Earth bus size shall be 50x10
mm minimum.
4.07.00 Finish
4.07.01 Bus conductor shall be given a coat of black matt paint to facilitate efficient heat
dissipation. However, effect of painting shall not be taken into consideration
while sizing of the bus conductor.
4.07.02 Inside of the bus enclosure shall be treated with a matt paint of dark colour,
preferably black to facilitate efficient heat dissipation. The shade of exterior
Vol. – IV ELECTRICAL SYSTEM Page 131 of 152
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METTUR THERMAL POWER STATION - I (4X210MW)
surface finish shall be light grey IS Shade # 631 for indoor and battle ship
grey IS Shade # 632 for outdoor.
4.07.03 All supporting steel structures shall be finished with an undercoat of high quality
primer followed by two coats of synthetic enamel paint.
4.07.04 Pre-treatment consisting of degreasing, derusting etc. shall be done on all
fabricated parts before painting or galvanising.
4.07.05 Paints shall be carefully selected to withstand heat and weather conditions. The
paint shall not scale off or crinkle or get removed by abrasion due to normal
handling.
4.07.06 Sufficient quantities of all paints and preservatives required for touching up at site
shall be furnished.
4.08.00 Tests
:
9. Current ratings
Rated continuous current : As per requirement
Rated short time withstand duration : 1 second
Rated peak withstand current kA (peak) : 105 kA
:
10. Insulation level
Rated voltage : 415 V
Rated insulation voltage : 1100
1 min dry power frequency withstand : 2.5 kV
Impulse with stand :
:
11. Support insulators
01.00.00 General
01.01.00 This specification covers the general description of design, manufacture and
construction features, testing, supply, installation and commissioning of
FGD lighting System/Area Lighting system equipment.
Areas to be covered in this package are entire FGD buildings including FGD
and its auxiliary systems operational areas/platforms/buildings , Mill premises
including Mill maintenance, Transfer towers & Conveyor galleries, control &
switchgear room, Switchgear/MCC room, Compressor building, Piping gallery,
cable gallery, all roads within battery limit and area illumination of the above
premises.
Illumination of Transformer and switchgear building/area adjoining roads etc.
are also included in the scope of the bidder.
Any other area/premises roads not specifically mentioned here but which fall
under the battery limits of this package are also included in the scope.
02.01.00 All work shall be carried out as per the codes & standards chapter of this
volume
The illumination of various indoor and outdoor areas in the FGD Plant and
off site areas shall be provided as described here. The lighting system of
various areas shall comprise of one or more of the following systems:
(a) Normal AC Lighting System
(b) Emergency AC Lighting System
(c) DC Lighting System
This system shall be provided for certain important areas in the main plant.
The lighting fixtures connected to this system shall be normally "ON" along
with the normal AC system. These shall be fed from emergency lighting
panels (ELPs) which in turn shall be fed 3-phase, 4-wire supply from the
emergency lighting distribution boards (ELDB'S). These lights shall go off
for a few seconds in case of AC supply failure at Emergency Switchgear,
but shall be automatically restored when Emergency power supply is
provided from the DG supply.
03.03.01 At strategic locations in the FGD Plant, a few lighting fixtures fed from
220V, DC supply, shall be provided to enable safe movement of operating
personnel and access to important control points during an emergency,
when both the normal AC and Emergency Lighting system fail. These
lighting fixtures shall be fed from 220V DC LDBs which in turn shall be
fed from DC lighting panels
6. Different Lighting Systems envisaged for various plant areas are indicated
in Annexure-B: While finalizing the detailed layout of lighting fixtures, the
position/location and layout of equipments should be taken into account to
have adequate illumination at desired locations.
7. LED Luminaires:
LED Luminaires shall be used for the lighting of all the Control Rooms and
& Control Equipment areas, all HT & LT Switchgear rooms and all Street
lights in Bidder's scope. In false ceiling area LED luminaires shall be
recessed mounting type & in non-false ceiling area the LED luminaires
shall be surface mounting type.
The individual lamp wattage for LED shall be min 3 watt. The LED chip
efficacy shall be min 120 Lm/W. The luminaire efficacy shall be not less
than 70 Lm/W. Suitable heat sink shall be designed & shall be provided in
the luminaire. The LED used in the luminaires shall have colour rendering
index (CRI) of Min 65. Colour designation of LED shall be “cool day light”
(min 5700K) type. The LED luminaire shall have minimum life of 25,000
burning hours with 80% of lumen maintenance at the end of the life. The
beam angle for LED chip shall be 120 degrees. The max. junction
temperature of LED shall be 85 deg C, further the lumen maintenance at
this temperature shall be min 90%. The THD of LED Luminaires shall be
Vol. – IV ELECTRICAL SYSTEM Page 136 of 152
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CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
less than 10%. Further the EMC shall be as per relevant standards. The
power factor of the luminaire shall not be less than 0.9. The marking on
luminaire & safety requirements of luminaire shall be as per IS standards.
Suitable heat sink with proper thermal management shall be designed &
provided in the luminaire. The connecting wires used inside the system,
shall be low smoke halogen free, fire retardant PTFE cable and fuse
protection shall be provided in input side specifically for LED luminaires.
Care shall be taken in the design that there is no water stagnation anywhere.
The entire housing shall be dust and water proof protection as per IS 12063.
Driver Circuit: LED modules and drivers shall be compatible to each other.
The LED module driver’s ratings and makes shall be as recommended by
corresponding LED manufacturer.
9. All lighting fixtures and control gears shall be powder coated. All outdoor
fixtures shall be weather proof and of IP55 degree of protection.
10. Lighting panels shall be powder coated with color shade RAL9002.
Lighting panels shall have IP55 degree of protection.
12. Power supply shall be fed from 415 / 240 V normal AC supply, emergency
AC supply (wherever available) and 220V DC supply through suitable
number of conveniently located lighting distribution boards (LDB) and
lighting panels (LP). AC lighting supply shall be isolated from main supply
by isolation transformers of max. rating of 100KVA and fault level
restricted to 3 KA at Lighting Panels.
Vol. – IV ELECTRICAL SYSTEM Page 137 of 152
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CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
13. At least one 6/16A, 240V AC universal socket outlet with switch shall be
provided in offices, cabins, etc. Further 20A, 240V AC industrial receptacle
with switch shall be provided strategically in all industrial areas (For
conveyor gallery at 30m interval on both sides and for yard conveyor at
50m interval on one side). Suitable number of 63A, 3ph, 415V AC
industrial receptacles shall be provided for entire plant for welding
purposes, particularly near all major equipment and at an average distance
of 50m. Atleast one 63A, 3ph, 415V AC receptacle shall be provided in
each floor of off-site buildings/ structures, at 50m interval (starting from
one end) on both sides of the conveyor galleries and at 50m interval on one
side of the yard conveyor. In LS handling plant, One no 10A, 24V AC
receptacle with IP55 DOP shall be provided in each switchgear/ MCC
room, Pump house, TPs, crusher house. 24 V single phase industrial type
switch & socket(3 pin) of rating 20A shall be provided at specific areas of
FGD plant, LS handling Plant transfer points and conveyor gallery, all other
areas by 1-4 way & suitable loop-in loop-out of 2 core -16 sq.mm
Aluminium cable shall be used and maximum distance between two
adjacent points shall be 50 Mtrs.
14. In the hazardous areas like gas/ liquid fuel storage/ handling areas lighting
shall be flame proof.
15. All fluorescent fixtures, shall have energy efficient 'T5' type fluorescent
lamps except the fluorescent fixtures used for division 2 hazardous area.
The louvers of these fixtures shall be designed for 'T5' type fluorescent
lamps. All fluorescent lamps shall be have "Cool day light" colour
designation. The mirror optics type fluorescent fixtures shall have no
iridescence effect. Fixtures with better efficiency and upgraded proven
system may also be considered
For the DC Lighting. Tube light fittings with electronic choke suitable for
220V DC operation shall be considered.
04.01.01 In general, Illumination for all other areas/buildings within the boundary
limit of FGD Plant and accessories, even if not specifically mentioned here,
shall be provided.
04.02.00 All luminaires and their accessories and components shall be of type readily
replaceable by available Indian makes.
04.03.01 Ceiling Fans, to be provided in all the office area (irrespective of Air
conditioning) and non-air conditioned control room area, shall be suitable
for operation on 240 V +/-10%, 50 Hz, AC supply comprising of class ‘E’
or better insulated copper wound single phase motor, 1200mm sweep,
aerodynamically designed well balanced AL blades (3 Nos.), down rod, die
cast aluminium housing, capacitor, suspension hook, canopies etc. finished
in stove enameled white or with electro static powder coating. Power factor
of fans shall not be less than 0.9. Fan regulators shall be stepped electronic
type suitable for operation on 240V +/-10% AC supply.
04.04.00 Junction Boxes, Conduits, Fitting & Accessories , Pull Out Boxes
Junction box for indoor lighting shall be made of fire retardant material.
Material of JB shall be Thermoplastic or thermosetting or FRP type.
Junction boxes for street lighting poles and lighting mast shall be Fiber
glass reinforced polymer junction boxes. The degree of protection shall be
IP55. All switches and receptacles upto 16A shall be modular type. These
shall be provided with pre-galvanized/galvanized modular switchbox &
plate. Conduits, Pipes and Accessories Galvanised heavy duty steel
conduits for normal area and galvanised heavy duty steel conduits with an
additional epoxy coating for corrosive area shall be offered. Alternatively
glass reinforced epoxy conduits with comparable compressive and impact
strength with that of heavy duty steel conduits may be offered. Rigid steel
conduits shall be heavy duty type, hot dip galvanised conforming to IS :
9537 Part-I & II shall be suitable for heavy mechanical stresses, threaded
on both sides and threaded length shall be protected by zinc rich paint.
Conduits shall be smooth from inside and outside. Flexible conduit shall be
water proof and rust proof made of heat resistant lead coated steel. Pull out
boxes shall be provided at suitable interval in a conduit run .Boxes shall be
suitable for mounting on Walls, Columns, Structures, etc.. Pull-out boxes
shall have cover with screw and shall be provided with good quality gasket
lining. Pull out boxes used outdoor shall be weather proof type suitable for
IP :55 degree of protection and those used indoor shall be suitable for IP :52
degree of protection. Pull out box & its cover shall be hot dip galvanised.
04.05.01 Lighting wires shall be 1100 V grade, light duty PVC insulated unsheathed,
stranded copper/aluminium wire for fixed wiring installation. colour of the
Vol. – IV ELECTRICAL SYSTEM Page 139 of 152
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TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
PVC insulation of wires shall be Red, Yellow, Blue and Black for R,Y,B
phases & neutral, respectively and white & grey for DC positive & DC
negative circuits, respectively. Minimum size of wire shall not be less than
1.5.sq.mm. for copper and 4 sq.mm. for aluminium.
04.06.01 The Street Light system and peripheral lighting shall be designed generally
in line with design guidelines. The Poles shall be mounted above ground
using base plate and minimum height of pole shall be 8 mtrs The poles shall
be hot-dip galvanized as per relevant IS2629/ IS2633/ IS4759. The average
coating thickness of galvanizing shall be min. 70 micron. The System shall
be capable of withstanding the appropriate wind load etc as per IS 875
considering prevailing soil/ site condition considering all accessories
mounting on pole. The street light poles shall have loop in loop out
arrangement for cable entry and light fixture / wiring protected with
suitably rated MCB.
04.07.01 Lighting Mast shall be of continuously tapered polygonal cross section hot
dip galvanised. The Mast shall be of 20 M or suitable height with lantern
carriage to enable raising/lowering for ease of maintenance, including the
Head Frame, Double Drum Winch, continuous stainless steel wire rope, in
built power tool, luminaires, suitable aviation warning light, lightning
alongwith necessary power cables within the mast. The mast shall be
delivered in not more than three sections & shall be joined together by slip
stressed fit method at site. No site welding or bolted joints shall be done on
the mast The Mast together with the fixtures shall be capable of
withstanding the appropriate wind loads as per IS:875. The Mast shall be
fabricated from special steel plates conforming to BS-EN10-025 and folded
to form a polygonal section. Suitable feeder pillar with TPN MCB,
contactors, timer, MCB and other necessary accessories for operation &
protection of the mast and fixtures shall be provided. Each mast shall be
provided with 8 Nos 400W metal Halide lamps with suitable control gears.
Minimum 4 Nos Lighting masts shall be considered.
04.08.00 Lighting fixtures shall generally be group controlled directly from lighting
panel. However, in office areas, control shall be provided through switch
boxes. Each switch shall control a maximum of three fluorescent fixtures.
04.09.00 A.C. normal, AC emergency and DC system wiring shall run throughout in
separate conduits. Wires of different phase shall run in different conduits
04.10.00 Lighting panels, etc. shall be earthed by two separate and distinct
connections with earthing system. Switch boxes, junction boxes, lighting
fixtures, fans, single phase receptacles etc. shall be earthed by means of
separate earth continuity conductor. The earth continuity conductor 14
SWG GI wire shall be run alongwith each conduit run. Cable armours shall
be connected to earthing system at both the ends.
04.11.00 Alternately Vendor may offer technically superior and proven product
subject to approval of owner.
05.00.00 Tests
05.01.00 All equipment to be supplied shall be of type tested design. During detail
engineering, the bidder shall submit for Owner's approval the reports of all
the type tests as listed in this specification. These reports should be for the
test conducted on the equipment similar to those proposed to be supplied
under this contract and the test(s) should have been either conducted at an
independent laboratory or should have been witnessed by a client.
05.02.00 However if the bidder is not able to submit report of the type test(s) or in
the case of type test report(s) are not found to be meeting the specification
requirements, the bidder shall conduct all such tests under this contract at
no additional cost to the owner either at third party lab or in presence of
client/owners representative and submit the reports for approval.
05.03.00 All acceptance and routine tests as per the specification and relevant
standards shall be carried out. Charges for these shall be deemed to be
included in the equipment price.
05.04.00 Selection of samples for type test, acceptance test & routine test and
acceptance criteria for all the items shall be as per relevant I.S
05.05.00 Type test reports of the following items as per relevant standards shall be
submitted for approval.
05.06.01 All lighting fixtures, lamps and other items shall be subjected to acceptance
and routine test, as per relevant specified standards.
Vol. – IV ELECTRICAL SYSTEM Page 141 of 152
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METTUR THERMAL POWER STATION - I (4X210MW)
05.06.02 Junction boxes, switch boxes, receptacle enclosure etc. shall be subjected to
physical and dimensional checks.
(a) Uniformity of coating - The coating of any article shall withstand four
1minute dips in standard copper sulphate solution without the formation of
an adherent red spot of metallic copper upon the basic metal.
(b) The quality of cadmium/zinc plating on items with screw threads shall be
free from visible defects such as unplated areas, blisters and modules and
shall be inspected visually.
(c) In addition, the plating thickness shall be determined microscopically/
chemically or electronically.
7.03.03 Control schematic and wiring diagram of 415V AC/220V DC lighting panel
with automatic changeover from AC to DC and vice-versa,415V
normal AC street/area lighting panel with automatic ON/OFF feature.
7.03.04 Technical leaflets and data sheet on each piece of equipment/ device such as
MCB, switch, fuse, receptacle etc. Type and routine test certificates of
transformer and cables.
7.03.05 QAP and relevant test certificates
7.03.06 Lighting layouts showing the disposition of fixtures, lighting panels/boards,
circuit distributions, conduit & wire routing.
7.03.07 Key Single Line Diagram for lighting distribution, board wise single line
diagram with feeder loading, cable schedule and interconnection chart,
design calculation for lighting.
7.03.08 AS-BUILT lighting layout and erection drawings, properly incorporating the
changes/alterations/field modifications, if any, as carried out at field along
with circuit distribution schemes of all lighting panels, conduit and cable
routing and as acceptable to the Owner.
7.03.09 Any other relevant drawings, data and manuals necessary for satisfactory
installation, operation and maintenance.
7.03.10 The contractor may note that the drawings, data and manuals listed are
minimum requirement only. The contractor will ensure that all other
necessary write-ups, curves and information required to fully describe the
equipment are submitted.
ANNEXURE-A
DC Emergency Lighting:
Sl. Area
Average Lux Level
No.
1. Unit Control Room 100
2. Control Equipment Room 100
3. Electrical Panel/Switchgear Control Room 100
4. Strategic Control Points ( In FGD Building 20
& Area, Battery Room, UPS Area, etc
5. Cable Vault & Galleries 1 fixture at every 20 metres
spacing along walkways
6. Stair Case 1 fixture at every 20 metres
spacing along walkways
7. Exit/ Entry of Main Plant Building 1 fixture
8. Fire Exit Sign 1 fixture
9. LS Handling Plant Control room - 50
Switchgear room - 50
Strategic control points - 20
Others areas - 20
1.02 The scope shall broadly cover the following and shall include such of those
items and accessories not mentioned here but required for satisfactory
operation of the system.
1.03 The integrated cable network for FGD plant shall be designed by the package
vendor keeping 100% spare cable pairs and will terminate all cables in the
Distribution box (D.B) inside the FGD plant building. From this D.B the
package vendor shall bring the cable to Small Auto Telephone Exchange
(SAX) and terminate the cable at the subscriber side of Main Distribution
Frame (MDF) of the SAX including jumpering of cables & commissioning of
the plant telephone system. The telephone handsets shall be provided by the
bidder.
1.04 The Bidder shall indicate the size/space for a separate room for above system.
The room shall be suitably airconditioned & illuminated.
1.05 Telephone connections shall be provided at each room of the office building,
shift offices, Control rooms cum switch gear rooms, ECRs, MCC’s, cable
basement, laboratory etc.
2.02 FDA system will be designed based on the following broad parameters:
i) All electrical premises, cable galleries/ tunnels, control rooms, offices etc.
will be provided with fire detection & alarm (FDA) system. The system
will have a network of detectors with a central control panel and
communication panels.
2.03 The scope shall broadly cover the following and also shall include such of
those items and accessories not mentioned here but required for satisfactory
operation of the system.
Break glass type manual call points with chain & hammer (with or without
hand set) / Pull down type manual call point.
Power supply from UPS system for Local Graphics computer and printer.
Provision for interlocking with automatic fire fighting system in the panel.
Fire Alarm System shall be supplied along with HMI & required software
loaded.
The fire alarm panel shall have auto dialer facility to inform to central fire
station of Aloke Steel through plant telephone network. However the FDA
panel shall have Ethernet connectivity port with TCP/IP protocol to connect
plant LAN in future. The supplier of this package shall keep necessary
software & hardware in his scope of supply.
Provision for tripping of ventilation system (in cable tunnel, cable basement,
switch gear room etc. as defined in ACVS chapter) in the panel.
All types of cables keeping 20% spare cable core in the cable and cabling
accessories.
Erection materials
GI pipes /GI conduits /PVC rigid conduits and other accessories wherever
required for laying of cables.
Near all drives local control stations shall be provided. Local stations shall
have sheet steel construction, dust and vermin proof, and wall/structure
mounting. Push buttons shall be mounted on front hinged gasketted and
lockable door. For HT motors, start, stop, and emergency stop push button and
for LT motors, open/close/trip or start/stop, as applicable, shall be provided
along with Local/Remote Selector switch, ON/OFF indication lamps, ammeter
for motor rated 30 kW and above..
Suitable knockouts with glands shall be provided on the bottom or top cover
for cable entry. Terminals shall be suitable for 2 cores of 2.5 sq.mm
conductors with 20% spare terminals. Stop push button to be lockable type
with mushroom head and key to release. Enclosure conforming to IP-54 class
for indoor and IP55 with canopy for outdoor. Explosion proof/increased safety
type shall be provided in hazardous areas.
All LPB stations shall be made of Cast Aluminium with minimum thickness of
2.5 mm. Press to stop and press to release (red colour) shall be provided for all
the motors. All LPBS for HT Motors shall be provided with Ammeters.
Indicating/monitoring/annunciating devices:
ILLUMINATION :
Lamps BAJAJ/ CROMPTON GREAVES/ GE
LIGHTING/ PHILIPS
Light fitting (fixtures) BAJAJ/ CROMPTON GREAVES/ GE
complete with all accessories LIGHTING/ PHILIPS
except lamp
Lighting wire (pvc) CCI/ DELTON/ FINOLEX/ NICCO/ UNIVERSAL
5A/15Aa piano switch ANCHOR/ ELLORA/ MDS LEGRAND/
PRECISION
Flame proof light fitting BALIGA
Exhaust fans CGL/ KHAITAN/ BAJAJ
Ceilling fans CGL/ KHAITAN
FIRE DETECTION & ALARM (F.D.A) SYSTEM
DEVICES MAKES
Vol. – IV ELECTRICAL SYSTEM Page 151 of 152
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TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
NOTE : For items not indicated above, bidder shall have to obtain prior approval from the
purchaser / consultant.
TENDER SPECIFICATION
FOR
SEMI DRY FLUE GAS DESULPHURIZATION
(FGD) SYSTEM & ITS AUXILIARIES
VOLUME – V
MECON LIMITED
RANCHI – 834 002
INDEX TO VOLUMES
Volumes Title
Volume – I Commercial
Volume – II Technical
Volume - IIA General Technical Specification
Section 01.00 Preamble
Section 02.00 Intent of specification
Section 03.00 Project information
Section 04.00 Special instructions to Bidder
Section 05.00 Scope of work, supply & Services
Section 06.00 Quality Assurance system / Requirement
Section 07.00 Painting
Section 08.00 Finalization of sub-vendors / sub-contractors
Section 09.00 Performance Guarantees
Section 10.00 Terminal points & Exclusion
Section 11.00 Layout and maintenance requirement
Section 12.00 Drawings / Documents to be submitted along with Bid / Offer
and after award of contract
Volume -IIB Technical Specification
Section 01.00 Flue Gas Desulphurisation System
Section 02.00 Technical Data Sheets – Mechanical
Volume -IIC Balance of Plant (BOP)
Section 01.00 Water Supply Facilities System
Section 02.00 Air conditioning & Ventilation System
Section 03.00 Elevators, Cranes & Hoists
Section 04.00 Fire Protection System
Section 05.00 Piping, Valves & Fittings
Section 06.00 Thermal Insulation, Lagging, Cladding
Section 07.00 Compressed Air System
Volumes Title
Volume - III Instrumentation & Control System
Volume -IV Electrical System
Volume -V Civil, Architectural & Structural Works
Volume -VA Civil Works.
Volume -VB Architectural Works
Volume -VC Structural Works
Volume -VI Mandatory Spares and Tools & Tackles
Volume -VII Tender Drawings
01.01 Introduction
This section covers entire civil engineering work including design, supply and
construction for all buildings, structures and facilities for all production, auxiliary units,
foundations for all buildings, structures and equipments, pavings, roads, water supply
and sanitary system for FGD system and all other miscellaneous civil engineering work
that will be necessary for completing this package on a turnkey basis for Flue Gas
Desulfurization (hereafter, FGD) and Auxiliary system to be used in the 4x210 MW
MTPS-I Project, at Mettur, Tamil Nadu in line with scope of works specified elsewhere
of this specification, All civil, works including design as per FGD & Auxiliary system
requirements are in Bidder’s scope. Description of various civil items of work under
this specification and nature of work in detail are given hereinafter.
a) It is not the intent to specify herein all the works in the scope of the contract. The scope
also includes all other buildings, structures and works necessary, which are not
specifically mentioned here but required for construction, operation and maintenance of
all structures covered under the EPC package, are deemed to be included in the scope of
the Bidder. All works shall conform to the relevant specifications. The works shall
conform to high standards of design, engineering and workmanship. Design and
construction shall conform in every respect to all local and state regulations governing
such works and to stipulations of Indian Standards unless stipulated otherwise in detail
specification. The Bidder's detailed design and scope of supply shall include all
components and systems, whether included in the system descriptions or not, required
to provide a complete and fully functional facility. This shall include all type of Civil,
Structural & Architectural work required for successful completion of scope of work of
the bid document.
c) All materials including cement, reinforcement steel, foundation bolts, inserts, structural
steel etc. and all other construction materials required for successful execution of civil
works shall be supplied by the Bidder at his own cost.
d) The scope shall also include setting up by the Bidder a complete testing laboratory in
the field to carry out all relevant tests required for the civil works for the project.
e) The work shall be carried out according to the design/drawings to be developed by the
Bidder and approved by the Owner/ Consultant. For all buildings and structures,
foundations, etc., necessary layout and details are to be developed by the Bidder
keeping in view the statutory & functional requirements of the FGD plant and facilities
and providing enough space and access for operation, use and maintenance. Certain
minimum requirements are indicated in this specification for guidance purpose only.
However, the Bidder’s offer shall cover the complete requirements as per the best
prevailing practices and to the complete satisfaction of the Owner.
f) Bidder shall inspect the site, examine and obtain all information required and satisfy
himself regarding matters and things such as access to site, communications, transport,
right of way, the type and number of equipment and facilities required for the work,
availability of local labour, materials and their rates, local working conditions, weather,
flood levels, subsoil conditions, natural drainage, etc. Ignorance of the site conditions
shall not be accepted by the Owner as basis for any claim for compensation or
extension of time. The submission of a bid by the Bidder will be construed as evidence
that such an examination was made and any later claims / disputes in regard to price
quoted shall not be entertained or considered by the Owner on account of ignorance of
prevailing site conditions.
g) The Bidder's detailed design and scope of supply shall include all components and
systems, whether included in the system descriptions or not, required to provide a
complete and fully functional facility.
h) Some of the existing structures or facilities of power plant may be utilised during
construction of FGD system works, based on prior permission obtained from Owner’s
Engineer in charge at site. The Bidder to note that they shall have to dismantle and
remove the staging and other temporary facilities on completion of work, clear and
clean the site and make good any damages caused to the structure and restore to original
condition at his own cost.
i) The works covered in this section consists of collection of all site related data,
conducting site investigations, design, preparation of all construction drawings, supply
of all labour, supervision, all materials, slip form equipments, scaffolding, fuel, water,
construction equipment, tools and plant supplies, transportation, storage, construction,
fabrication, erection and testing where necessary, of all structures required for housing
all equipment and civil works for all services required for the package as defined in the
specification document. The Civil works shall include those required for Installation,
Commissioning, testing, operation and maintenance of structure/ system required for
the package.
j) The Site System shall provide roadways inside the plant boundary, micro grading
levelling and storm water runoff drainage up to the boundary wall terminal point.
All Civil Works including design , related to all facilities required for the completeness
of this Package, shall be within the scope of this package.
The civil works for the buildings, structures, equipment foundations, facilities and
miscellaneous civil works to be provided for the project shall include but not limited to
the following:
a) Cable trenches, cable racks, duct banks, manhole and pipe trenches, Cable sleeper etc.
b) Supporting structures and platforms with access for utility pipelines, ventilation ducts,
Bus ducts and other equipments.
c) All roads, culverts, drainage & connecting the same to the existing nearest/ suitable
plant roads/ facilities. The roads shall be of similar type as of the main connecting roads
i.e. either R.C.C or Bituminous depending on the main connecting roads.
d) All water supply, plumbing and sanitary works including all fixtures for sewage
disposal for buildings / units / shed covered within the battery limit.
e) Collection & disposal of industrial effluents collected from buildings / units / shed
covered within the battery limit.
f) All necessary waterproofing, damp proofing and anticorrosive treatment with epoxy
coating to all reinforced bars, structures and foundations, including underground
construction.
g) All necessary civil works for crossing pipes/cables below for roadways and other
services within the battery limit and reconstructing of existing damaged utilities/
structures/roads etc.
h) Construction of all temporary facilities, building, offices, labour colonies, staff quarters,
roads and services required for this package.
i) Removal of debris, micro levelling of the site, included in the scope of contract prior to
completion of work.
k) Blasting shall not be permitted for excavation of foundation any other purpose near the
chimney and other main structures.
l) Site clearing, dressing, levelling and grading of formation to required levels and soil
compaction as necessary within the battery limits as shown in the bid drawing or as
directed by Owner.
m) Earthwork for buildings and equipment foundations, tanks, trenches, pits, sewers and
other underground / above ground construction work. Dewatering of the underground
works.
n) Back filling, soling and sub-grade work for all foundation, grouting, flooring, trenches,
pits for all structures/equipment included in the scope.
o) Encasing structural steel column bases as well as structural steel wall beams in RCC at
various locations as required.
p) Reinforced concrete work and PCC work in foundations, sumps, pits, trenches, tanks,
silos, all equipment, bucket elevators and other underground structures.
q) Reinforced concrete work and PCC work in foundations, columns, tie beams, beams,
staircases, slabs frames and other superstructures.
s) All masonry work in sub structure and super structure including plastering as required.
t) All finishing work to flooring, walls, ceiling, false flooring and false ceiling as required.
u) All finishing and painting work to masonry, concrete structures, steel works and wood
works.
w) Doors, windows, ventilators, rolling shutters, fire check doors, gates shutters etc.
x) All necessary Buildings / Units and equipment supporting structures and their
foundation system.
y) All Handrails, inserts, kerb angles, bolts, cage ladders, platforms and other
miscellaneous steel works.
a) Approval of the Bidder’s design drawings / documents means that these are checked for
conformity with applicable specifications and general conformity with the engineering
requirements covered in the specifications. Approval of the Bidder’s design drawings
and documents shall not relieve the Bidder in any way whatsoever of any of his
responsibilities under the Contract and the Bidder shall remain wholly responsible for
any error in his design drawings, unapproved disagreements with contract technical
specification.
Vol. – VA CIVIL WORKS Page 4 of 54
© 2020 MECON Limited. All rights reserved.
TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION-I (4X210MW)
b) The Bidder shall not make any change in the approved design drawings without the
prior written approval of the Owner/Consultant. Owner is not liable for approval of
document having additional changes on the design/ drawings already approved.
Manufacturing / procurement / fabrication prior to approval of design drawings shall be
solely at the Bidder’s risk.
c) In case of any deviations from the approved design drawings being called for at site due
to any reason, Bidder shall take approval on such change from Owner/ Consultant
before carrying it into effect at site. However, Owner is not liable for re-approval of
design/ drawings already approved.
d) In general no foundation shall rest over back filled soil. However, small foundation may
rest over the back filled soil after asserting the designed bearing capacity.
f) All design calculations and drawings shall be in English and shall be in SI units.
The Bidder shall make the layout and levels of all structures from the general grid of
the plot and the nearest GSI benchmark or other acceptable benchmark as per the
directions of the Owner.
All levels have to be established with respect to the permanent bench and reference
bench mark shall be indicated by the Owner.
Vol. – VA CIVIL WORKS Page 5 of 54
© 2020 MECON Limited. All rights reserved.
TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION-I (4X210MW)
The bidder shall be solely responsible for the correctness of the civil works.
Design and construction of buildings, structures etc. shall take into account requirement
for operation and maintenance of all equipment and its users. The buildings will have
good architectural features. The surrounding areas shall be properly micro levelled and
graded. The architectural design concept of buildings structure shall be evolved
considering the functional, technological and other requirements for efficient operation
ensuring comfortable working environment for personnel, satisfying the aesthetic
requirements. Special care shall be taken to provide elegance and aesthetics, with
effective use of appropriate treatment, materials fittings and finishes.
Due consideration shall be given for adequate natural lighting and ventilation for plant
and non-plant buildings both.
Internal finishes shall be provided with latest available materials as per finishing
schedule with due consideration of the functional aspect of the area.
External finishes shall be provided with latest materials as per finishing schedule for
improving the aesthetics.
Each building shall have its own identity. However, a total homogeneity shall be
maintained in the design of all buildings.
Adequate frontage shall be provided to all important buildings to create a better visual
impact.
Drainage of rainwater from roof shall be ensured by rainwater down comers with
necessary fittings & fixture and proper slope.
All concrete roofs exposed to weather shall be provided with water proofing treatment
using latest Polymer based cementatious material of approved reputed manufacturer
like CICO, SIKA, FOSROC or equivalent consisting of minimum 2 coats of acrylic
polymer based cementatious slurry coating with one layer of fiber glass cloth in
between over screed concrete laid to required slope. 50mm thick PCC (1:2:4) shall be
cast over water proofing treatment, in panel not exceeding 1.2M X 1.2M size with
0.56mm diameter galvanized chicken wire mesh reinforcement. Joints shall be sealed
with sealing compound.
All buildings shall be provided with 1000mm (minimum) wide apron along with
garland drain all round the periphery of the building. Apron shall be of minimum 75mm
thick PCC(M 20) finished with 15mm thick cement mortar (1:4) and neat cement
(chequered).
Separate ladies and Gents Toilet & rest room facilities in all major buildings
Separate fire exits shall be provided in all buildings as per requirements.
Equipment foundations for all the systems specified in mechanical, electrical section of
this specification.
All other civil and structural buildings shall be developed in conjunction with the above
aspects.
The architectural design concept of building structure shall be evolved considering the
functional, technological and other requirements for efficient operation, ensuring
comfortable working environment for personnel, satisfying the aesthetic requirements.
Special care shall be taken to provide elegance and aesthetics, with effective use of
appropriate treatment, materials fittings and finishes. To achieve above objective the
Contractor shall employ a qualified Architect / Architectural firm. The Contractor shall
submit all the architectural drawings for approval of Owner. The decision of Owner
shall be final and binding, in all respect of functional requirements to Contractor.
The Contractor shall obtain and be conversant with all laws, by-laws, regulations of
local and Statutory Bodies as applicable to the project. The architectural concept
evolved should also take care of these requirements. The Contractor shall provide the
drawings and documents for such statutory approvals.
All new structures shall be connected by roads and the roads shall be terminated up to
the nearest existing MTPS-I roads. Any damage to existing road/ facilities shall be
refurbished by Bidder.
Drainages:
Discharge point shall be nearby existing nallah or existing drains. If discharge is
planned into the existing drainage system, proper drainage study for the carrying
capacity and design parameter of existing drains shall be done and submitted to the
owner for approval.
Sewage:
Sewage discharge point shall be nearby existing STP or existing sewage line/manhole.
If discharge is planned into the existing sewage line/ manhole, proper sewage study for
the carrying capacity and design parameter of existing sewage shall be done and
submitted to the owner for approval.
The following documents are to be submitted for the approval of the Owner/Consultant,
prior to commencement of fabrication & erection / construction. All drawings shall be
of standard sizes (Metric system). The list is not exhaustive but indicative only.
a) Layout drawing with co-ordinates of roads, buildings and facilities, piping / cable
corridors, pipe and cable trestles, provision of landscaping, diversion drains, equipment
lay down areas etc. within the battery limit.
b) Drawing showing underground facilities with co-ordinates of these facilities like buried
pipes, buried cables, trenches, ducts, sewer, drains, sumps, pits, culverts, foundations
etc.
c) Geotechnical investigation Methodology along with layout of various proposed tests
and Geotechnical investigation report along with foundation recommendation for
various buildings / structures / facilities.
d) Storm water drainage study furnishing levels of various terraces arrangement and
details of drains, culverts etc. for storm water drainage system.
e) Design basis memorandum for all buildings, facilities, services and structures.
f) Landscaping scheme, scheme for supply of potable and service water to all buildings.
g) Architectural floor plans, elevations, cross sections and perspective view in colour for
all buildings.
h) Design calculations and drawings for foundations/substructure and superstructure of all
structures within scope
i) Design calculations including dynamic analysis and drawings for all foundations
subjected to dynamic loads. Design and drawing of vibration isolation system shall also
be furnished.
j) A write up on dewatering system proposed at the time of construction where deep
construction such as for Conveyor tunnels and pump house etc. are to be executed
where water table is encountered.
k) Design calculations and drawings for all facilities and services like roads, culverts,
bridges, paving, road crossings, drainage pump house (if required), drains, sewers,
water supply, water tank, sumps, tunnels, trenches, ducts, equipment, DG,silos etc.
l) Drawings of all architectural works including finish schedule, colour scheme (both
internal and external), doors and windows, flooring and false ceiling, etc.
m) Design calculations and drawings for plumbing and building drainage.
n) All other designs, details / drawings or any other submissions as indicated elsewhere in
this specification and as required by the Owner/Consultant.
o) Design calculations and drawings for structures and foundations in switchyard,
transformer yard, etc.
p) All drawings / prints shall bear a stamp at a prominent place indicating whether the
drawings are submitted for approval or for information. Drawings supplied by the
Bidder shall bear the date and signature of a responsible person of the Bidder.
q) Details of corrosion protection measures for all structures
r) Total quantity of concrete (grade wise), reinforcement steel (diameter wise) and
structural steel (section wise) in all construction drawings.
s) Write up on various statutory requirements and their compliance for various buildings
and facilities.
t) Copies of all reports on investigation and studies carried out by the Bidder as per the
scope.
u) Field Quality Assurance plan for Civil, Structural and Architectural works.
v) Structural analysis/ design shall be carried out using STAAD.Pro software. All
loads applied on structural frame work in STAAD.Pro input shall be clearly shown
in load calculation. Soft copies of design calculations in editable format, sources and
validation report for software, drafting (AutoCAD), shall be submitted for Owner’s
acceptance.
w) All relevant civil/structural materials shall be brought to site along with necessary test
certificates and should be submitted to the Owner at site for approval. Bidder shall
submit a list of preferred makes as given in the format for the materials.
x) List of all sub-contractors that the successful Bidder proposed to employ, indicating
their addresses with telephone number, experience on similar jobs, name, qualification
and experience of persons who shall be employed in the job on behalf of the sub-
Bidders etc. shall be submitted to the Owner/Consultant. Only the sub-contractor
approved by the Owner/Consultant shall be engaged on the job by the contractor.
Bidder to note that subletting of work on back to back basis shall not be permitted.
Plant storm water drainage system including connecting to the nearest nallah/existing
storm water drains. In case of connection with existing storm water drains, water
carrying capacity of such drains up to final disposal point to be checked by Bidder and
if the drains are not capable to carry storm water of FGD area, new drains with suitable
layout or up gradation of existing drains as per design requirements considering storm
from power plant area and FGD area.
Rain water harvesting for the complete package within the battery limit.
Construction water will be made available at one point near the proposed FGD system
by the owner. Pumping, Storing, providing pipe line for distribution etc. complete for
construction water for the construction shall be part of Bidder’s scope.
Construction power shall be arranged by the Bidder by arranging from the Owner
approved power distribution source available in the vicinity of the site. All works
involved for substation, transmission lines and further distribution etc. complete for
construction power for the construction shall be part of Bidder’s scope.
The Contractor has to carry out survey as per requirement such as for layout of
buildings, foundations, fixing centre lines, fixing layouts etc.
The Contractor has to verify the topography and any other additional information
required by conducting survey at his own cost.
The Bidder shall be deemed to have visited and carefully examined the site and
surroundings and to have satisfied himself about the nature of the existing structures,
underground services, general site conditions, the site for disposal of surplus materials,
debris, surplus earth etc. and all other items affecting the work. Claims due to ignorance
of site conditions will not be considered after submission of Bid.
Ground preparation including minor grading, shall be done by the Bidder. However the
Bidder of the package shall consider removal of grass, shrubs, plant & its root from the
proposed area which are likely to grow again after first cut cleaning by site grading
work done by Owner. Certain amount of cutting, filling, and removal of top layer of
expansive soil, if any, shall be included in the scope of this bid document. Where earth
Vol. – VA CIVIL WORKS Page 10 of 54
© 2020 MECON Limited. All rights reserved.
TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION-I (4X210MW)
fill is intended, the area shall be stripped of all loose / soft patches or top soil containing
objectionable matter before filling commences. Any structure or services existing at the
site shall be removed / re-routed with the permission of the Owner. Existing wells, pits,
marshy areas etc. shall be filled up with earth of approved quality.
Mainly all the roads shall be in line with existing type of roads and designed and
constructed as per relevant IRC codes/MORTH specification. Vehicular parking areas
shall be of flexible pavement type with wet mixed macadam (WMM) base and
bituminous topping on prepared surface. The roads shall be of similar type as of the
main connecting roads i.e. either R.C.C or Bituminous depending on the main
connecting roads.
On either side of the roads, open drains shall be provided. Minimum clear width of the
drain shall be 450 mm. All the drains shall be in RCC. Drainage lines and other
underground services shall be located at least 1.2 m clear from the edge of the road. All
service and utility lines crossing the roads shall be taken up through NP3 class RCC
pipe designed for impact loading. Culvert shall also be generally using NP3 class pipe.
The Contractor may adopt option of providing RCC box culvert.
The storm water drainage of the FGD and Auxiliary system area is included under the
scope of the Bidder.
Hence, the Bidder shall carry out the drainage study in coordination and consultation
with the other Contractor who will be carrying out road & storm water drainage work of
other packages. All the drains shall be suitably connected to either existing power plant
drains or finally connect to outside plant boundary existing or propose drainage outlets.
The scope of Bidder shall include collection of the entire sewage form toilet, wash area,
etc. in a catch pit located just outside individual building / unit.
Carrying out the work of Sewage routing, shall provide the network of underground
sewage collection in gravity flow and shall arrange to lead the sewage to nearest
existing Sewage line/ manhole.
All paving works shall be carried out after successful installation of underground
sewage system.
Entire paving area shall be provided with RCC paving over metal/ laterite soling. Plinth
protection around all buildings shall be provided to a min width of 1000 mm or the
distance between the brick wall to the garland drain.
Paving shall be carefully planned such that maintenance access roads minimum 4 m
wide to all major equipments are available. This area shall be designed for heavy loads
similar to design of roads. All drain / trench covers in these areas shall be designed to
withstand truck loading. All drain / trench covers in these areas shall be designed to
withstand truck loading.
Plumbing and fixing of fixtures within the battery limit shall be provided in line with
the technical specification.
All the buildings will be provided with rain water harvesting system approved by
relevant state govt. authority for entire FGD area.
a) Ambient Temperature
b) Rain fall
The site is located in basic wind speed zone of 47 m/s as per IS: 875 (Part 3).
Vol. – VA CIVIL WORKS Page 12 of 54
© 2020 MECON Limited. All rights reserved.
TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION-I (4X210MW)
All structures shall be designed for the most critical combinations of dead loads,
imposed loads, equipment loads, wind loads, seismic loads, temperature loads, forces
developed due to differential settlement and any other loading conditions which can
occur during the design life of the facility.
Dead loads consist of the weights of the complete structure with finishes, fixtures,
partitions, wall panels and all equipment of semi-permanent nature including storage
structures (tanks, silo etc.), partitions, roofing, piping, cable trays, bus ducts etc. The
content of storage structures etc. shall be measured at full capacity for this purpose.
The piping loads, cable tray loads and the contents of the storage structures shall be
listed separately so that they can be excluded from dead load when dead loads are
acting as stabilizing load for uplift.
The following unit weight of material shall be considered for computation of loads.
Loads given in IS: 875 (part-I) shall be made use of for material not listed below.
Table 1.1
Weights of Material
Material Unit weight (kN/m3)
Plain cement concrete 24.0
Reinforced cement concrete 25.0
Brick work 20.0
Cement plaster 21.0
Floor Finish 24.0
Listed below is the minimum SILL for the areas involved. Floors and supporting
members subjected to heavy equipment live loads shall be designed on the basis of the
equipment loads specified by vendor or specifically defined SILL whichever is greater.
Table 1.2
Superimposed Live Load (SILL)
Sl. No Description SILL Value
a) Roof
Flat accessible roof 1.5 kN/m2
Flat accessible roof with HVAC 5 kN/m2
equipments, etc.
Flat inaccessible roof 0.75 kN/m2
Sloped Roof As per code IS: 875 (Part-2)
b) All building floors & Stairs 5 kN/m2
c) Walkways of Conveyor Galleries 5 kN/m2 or Concentrated Load
of 3 kN at centre which ever is
critical
d) M.C.C. Floor 10 kN/m2
e) Equipment Load As applicable
f) Culverts & its allied structures Class “A” / Class “70R” as per
including Concrete pipes IRC standard whichever is
higher / load due to bull dozers
g) Underground basement, Surcharge of 10 KN/m2
h) Vehicular traffic Surcharge of 20 KN/m2
i) Covers for Channels Surcharge of 10 KN/m2
j) Pump Houses
Operating Floor Slab 15 KN/sqm or as required by
equipment supplier whichever
higher
Workshop 10 kN/m2
k) Other areas:
RCC floors (Offices, laboratories, 5 kN/m2
conference rooms and general
floors)
Balconies 5 kN/m2
Chequered plate / gratings 5 kN/m2
Walkways 3 kN/m2
Toilets 2 kN/m2
In addition to LL, Hung loads for electrical, ventilation & air conditioning minimum of
0.5 kN/m2 shall be considered.
For other areas LL shall be considered as per IS: 875 (Part-2).
Vol. – VA CIVIL WORKS Page 14 of 54
© 2020 MECON Limited. All rights reserved.
TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION-I (4X210MW)
Ponding effects due to framing deflections for roofs, if any shall be considered.
The various structures for the project are to be designed as per codal provisions of
IS:1893 for earthquake loads. The loads due to Earthquake are generated by the
response of the structure to design spectrum as specified in IS1893 (Part 1): 2016. The
site is located in Earthquake zone III and factors corresponding to that zone are taken in
calculation of response. The mass to be considered in seismic analysis shall comprise
of full dead load and the reduced percentages of live loads for calculating inertia
masses as given in Table 1.
Following values are used for the defining Design Basis Earthquake (DBE) which is
considered for the analysis:
Wind load calculation shall be as per IS: 875 (part-3) 2015 where Basic wind speed
(Vb)shall be taken as 47 m/sec with Risk coefficient k1 as 1.07 ( important building
having mean probable life of 100 years, k2 as Terrain roughness and height factor for
Terrain Category –2 and depending upon the height of the building,k3 as topography
factor with a value of 1 and k4 as 1,
kc=Combination factor
For the design of structures, wind force on Equipment, supported on frame including all
fixtures, piping, staircase, ladder, etc., exposed to wind shall be considered.
Design of structures shall be checked for the condition of wind load with gust factor.
For earth pressure the worst condition with dry / submerged and active, passive or at
rest condition shall be considered. (The pressure coefficient shall be adopted as
recommended in Soil Report or for the backfill material used.)
Coefficient of thermal expansion of steel shall be taken as per IS: 800 where the value
is given as 12x10-6/°C. Coefficient for thermal expansion for concrete shall be taken as
per IS: 456.
piping and supports, the friction force will be taken as the operating load on the support
multiplied by the applicable friction coefficient given below:
Table 2.4
Thermal Loads
Description Value
Surfaces Friction coefficient
Rolling supports 0.05
Concrete to steel 0.30
Any other bearing namely stainless steel, PTFE etc. can also be used.
Static and dynamic loads of major equipments shall be based on the manufacturer’s
data of the specified equipments and shall be considered in design in addition to the live
load. However, where the uniform floor live load adequately accounts for the
equipment moving weight, the weight of such equipment as a dead load shall not be
considered e.g. control room floors are usually designed for a live load that includes the
equipment weight also.
All equipments, tanks and piping design loading shall include hydraulic test loading.
Weight of equipments, ducts, tanks, pipes, conduits, etc. supported by structure shall
include maximum possible loading conditions i.e. flooded conditions and associated
impacts, test loading, anchorages and constraint effects.
Air and gas duct loads shall include weight of insulation, duct attachments, dust
accumulation loads, seismic, wind and other loads applicable.
All lifting beams and monorails shall have their design loads increased for impact
factor. Loads for hoists, monorails and elevators shall be taken as per IS: 875.
100 % of the lifted load including elevator live load plus the cab weight shall be
considered for the elevator support beam design. Pedestals in elevator pits shall be
designed assuming 100 % impact factor.
The design shall ensure that vibrations from any moving machinery transmitted from its
immediate foundations to adjacent buildings or areas of the same building shall be
suppressed in accordance with the recommendations of relevant codes of practice. Any
control room, administration facility and other permanently occupied office area shall
be structurally isolated from plant areas subject to frequent shock loads or containing
large oscillating or rotating plant and equipment.
Dust loads: All buildings / structures shall be designed for a dust load of 1 kN/m2.
Construction Loads: The integrity of the structures shall be maintained without use of
temporary framing struts or ties and cable bracing as far as possible. However,
construction or access considerations may dictate the use of temporary structural
systems. Special studies shall be made and documented to ensure the stability and
integrity of the structures during any periods involving use of temporary bracing
systems.
Future Loads: Loads from future expansion shall be considered when so directed by the
Owner/Consultant. Future loads may include any of the loads listed above.
Surge Loads: Surge loads may occur in some vessels or equipment. In such cases, the
magnitude and direction of the load shall be given by the equipment supplier.
Dead load : DL
Superimposed dead load : SIDL
Self weight of permanent equipment : EL
Live load on floor / walkway : LL
Superimposed live load : SILL
Live load on roof : LLR
Hoist, monorail loads : MR1
Wind load : WL
Seismic load : SL
Load due to soil pressure : SP
Load due to surcharge : SCL
Vol. – VA CIVIL WORKS Page 18 of 54
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The individual members of the frame shall be designed for worst combination of forces
such as bending moment, axial force, shear force and torsion. Permissible stresses for
different load combinations shall be taken as per IS: 456, IS: 800 & IS: 875 (all parts)
and other relevant IS codes.
For the design of sub structure only liquid pressure from inside and no earth pressure
and ground water Pressure and surcharge pressure from outside (applicable only to the
Structures which are liable to be filled with water or any other liquid) shall be checked.
For the design of sub structure combination of earth pressure, surcharge pressure and
ground water pressure from outside and no water pressure from inside shall be applied.
Ground water at ±0.00 level.
(o) Silos
The concrete silo shall be designed generally as per the criteria laid down in IS: 4995
(Part I & II).
The loading for the design of switchyard structures shall be as per IS: 802 Part 1/Sec
1:1995. Following loads shall be considered.
Switchyard structure shall be designed for the worst combination of above loads. The
factor of safety for design of members shall be considered as 2 for normal & broken
wire conditions and 1.5 for combined short circuit and broken wire conditions. Short
circuit forces and Seismic forces shall not be considered simultaneously.
Foundation shall be designed for a factor of safety 2.2 for normal and broken wire
condition and 1.65 for combined short circuit and broken wire conditions. Design of
foundation shall be carried out as per IS: 4091.
Flat roof
Accessible : 1.0KN/sq. m dust load
Non accessible : 1.25 KN/sq. m dust load
Load due to material on belt : 1.6 times design weight of the material on
belt
Spillage load
Gallery walk way : 1KN/sq. m
Seal plate : 1KN/sq. m
Vol. – VA CIVIL WORKS Page 20 of 54
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METTUR THERMAL POWER STATION-I (4X210MW)
Belt tension for twin conveyors : One belt at starting condition and one in
running condition
All civil works for the buildings, equipment foundations, facilities and miscellaneous
civil works to be provided for the project will include but not be limited to the
following:
a) Control cum MCC room building
b) Compressor house
c) Pump house(if required)
d) Booster fan,
e) Absorbers
f) Fabric filters
g) Lime conveying air compressor,
h) Dryer for lime conveying air compressor,
i) Fluidizing air blower with heater for lime storage silo,
j) Fluidizing air blower with heater for intermediate by-product silo,
k) By-product conveying air compressor,
l) Dryer for by-product conveying air compressor,
m) Fluidizing air blower with heater for main by-product silo,
n) Spray water pump,
o) Pulse jet compressor for bag filter,
p) Instrument air compressor,
q) Desiccant type air dryer for instrument air compressor,
r) Electric hoist with monorail,
s) RCC silos(lime storage silo, Main by-product silo, intermediate by-product silo)
t) Pipe supports
u) Rack & pinion type elevator
v) Foundation for steel water tanks
w) Passenger lift
01.13.01 General
This section applies to all earth and rockwork required for the construction of buildings,
any types of structure and burying service lines in the ground.
The Bidder shall satisfy himself as to the ground conditions on the site including the
nature of the strata to be excavated, obstructions, possibilities of flooding and such like
and shall allow for all provisions necessary to carry out the work in the most suitable
manner when submitting his tender.
Generally, all buildings and structures must be founded on bearing strata which means
that all excavation work for foundations shall meet the requirements of structural
analysis based on the results obtained from the soil investigation and of the available
information and instruction given in writing by the Owner/Consultant.
Excavation shall be done to the required dimensions and shall be finished according to
the specified lines and slopes, in a way acceptable to the Owner/Consultant. All
necessary precautions shall be taken to cause the minimum possible alteration or
disturbance to the material lying under and adjacent to the excavation final lines.
The fill materials used and source are to be examined and approved. Excavation
materials can be used if they fulfil the requirements.
Well graded (uniformity index not less than 5), non-cohesive and nearly silt free (silt
content not greater than 5%; up to 10% tolerated, except below footings of structures),
salt free (content less than 3%), soils free of organic matter (limit 2%).Decomposing or
compressible materials shall not be used.
All materials shall be of such nature and character that it can be compacted to the
specified densities in a reasonable length of time. It shall be free of highly plastic clays,
of all materials subject to decay, decomposition or dissolution, and of cinders or other
materials, which will corrode piping or other metal.
The intention is to use select fill below plinth, floors, roads, parking areas etc.
c) Natural inorganic soils: salt content not greater than 5%, organic matter less than 3%.
For other properties see under ‘Select fill’.
d) The intention is to use ordinary fill for non-built areas.
e) Special fill:
f) Special fill material shall be gravel or crushed rock (for other properties see under
‘Select fill’). The intention is to use special fill e.g. as sub-base material for tanks and
roads.
g) Rip-rap/Rock fill:
h) Riprap must be of a size suitable for the place where it is to be used, as determined by
the speed of the current, wave height and depth of water. Riprap shall be of deformable
and yielding construction, using round stones if the intention is to safeguard the
underlying ground against scour. If the rock infill is to be used as a foundation for
structural components, the aim should be to secure effective bedding of angular stones
under water. The stones must be weather and waterproof.
Where hard rock is met, the Contractor shall intimate the Engineer in writing.
Excavation in hard rock shall be done by chiseling or by such other agreed methods as
may be required. Levels of hard rock surface shall be taken and got approved by
Engineer before start of excavation.
The excavation shall be carried out by chiseling, wedging or such other agreed
methods. All materials excavated from, chiseling or any such methods shall be stacked
for measurement as directed by Engineer.
01.13.04 Excavation
i) The works shall be excavated either by hand or by use of excavating plant and tools
acceptable to the Owner/Consultant.
If somewhere, and for any reason, excavation is executed beyond the established design
level, the Bidder shall at his own expenses backfill with lean concrete to
Owner/Consultant’s approval, the volume corresponding to over-excavation. He shall
not receive payment for over-excavation not ordered.
01.13.07 Stockpiles and Disposal
Excavated material from the works selected by the Owner/Consultant for re-use shall be
placed immediately in its final position, if possible, or otherwise may be stockpiled or
deposited on site as directed by the Owner/Consultant.
The Bidder shall not have the right either to additional payment or to claim because of
work involved in stockpiling materials, re-use of for carting to the waste disposal areas.
Soil unfit for re-use shall be removed to sites approved by the Owner and shall not be
permanently deposited elsewhere. The Bidder shall trim and form the edges of spoil to
profiles and levels as directed by the Owner/Consultant.
The placing of materials within the waste disposal areas shall be made in layers not
exceeding 0.50 m in thickness in order to obtain an appreciable degree of compaction
by means of transportation equipment and/or if required by appropriate compaction
equipment.
All traffic to or from the waste disposal areas shall run over the surface of such areas in
order to achieve compaction.
01.13.08 Preparation of Foundation
All rock surfaces on which or against which concrete is to be poured shall be carefully
cleaned and roughened to the Engineer’s satisfaction.
The rock surface shall be free of oil, stagnant or running water, mud, loose rock, residue
and impurities or any other improper material. Rock faults, depressions and fractures
shall be cleaned to a depth equal to their widths and to sound rock at both sides.
Immediately before concrete placing, all rock surfaces shall be thoroughly cleaned by
means of air and water jets, wire brushes, sand jets or by any other devices necessary to
clean the foundation and keep it free of water, but shall be moistened prior to placing
concrete.
All earth surfaces against which concrete is to be poured, shall be clean and free of any
detrimental impurities, organic matter or unsuitable material. Immediately after
excavation, all such surfaces shall be moistened and treated as directed by the
Owner/Consultant and then protected by means of a lean concrete layer, 7.5 cm or PCC
thickness as shown in the design drawings, whichever is greater. No concrete is to be
poured until formation is inspected and approved by the Owner/Consultant.
01.13.09 Backfilling
Foundations and structures, pits, trenches etc. shall be backfilled with approved
material compacted in layers not exceeding 150 mm by suitable equipment until
optimum stability has been obtained to the satisfaction of the Owner/Consultant.
Compacting shall be carried out with special care by means of pneumatic or mechanical
rollers or other compactors of a type previously approved by the Owner/Consultant.
Density requirements as per standard Proctor Test shall be in accordance with relevant
parts of IS: 2720 and all tests shall be made by/on under the supervision of
Owner/Consultant at Bidder’s own expenses, at optimum moisture content:
The thickness of fill layers, number of passes and type of equipment to be used shall be
proposed to the Owner/Consultant after compaction tests have been made.
Surfaces receiving fill layers shall, if smooth, be previously scarified to obtain a good
key between the new fill layer and the sub-grade.
Backfilling of foundation work with approved materials shall be carried out only after
foundations have been inspected by the Owner/Consultant.
The material to be used for replacement of soil shall not contain soluble or swelling
components such as clays, or organic matters. Sand gravel mixtures of favourable grain
size distribution shall be used in exchange.
Prior to the commencement of work, three samples shall be taken from the anticipated
borrow area and tested in respect of IS: 2720 for Proctor density, optimum moisture
content, grain size distribution and content of soluble matters.
These three samples shall cover the approximate variation of materials to be expected
within the borrow area.
The fill material shall be placed in horizontal layers of not more than 15 cm in
compacted thickness. The fill moisture content shall be controlled and adjusted in order
to achieve a maximum of compaction. Fresh water shall be used for watering of soils.
The fill material shall be compacted by vibratory roller (min. weight 20T.). The
minimum required degree of compaction should be as defined under “Tests and
Properties”. One Proctor and three density tests shall be made at every fourth fill layer
prior to continuation of filling work. The testing location will be indicated by the
Owner/Consultant. The Bidder shall either provide all required laboratory facilities and
staff to perform the tests or he shall co-operate with an experienced soil testing
laboratory, subject to the approval of the Owner/Consultant.
The results of the tests shall be made available to the Owner/Consultant within 24 hours
of the tests. Filling work may be continued in case all tests performed show satisfactory
results.
Pipe beds shall be constructed to guarantee the uniform transmission of loads. The
bearing section for supported profiles shall cover at least an arc of 90.
Pipes shall be bedded in an earth foundation of uniform density and carefully shaped by
means of a template supported at the desired grade, to fit the lower part of the pipe
exterior.
compacted earth cushion having a thickness under the pipe of not less than one quarter
of outside pipe diameter with a minimum allowable thickness of 20 cm if not otherwise
specified.
Where a firm foundation is not possible at the grade established due to soft, spongy or
other unstable soil, all such unstable soil under the pipe and for a width of at least one
diameter on each side of the pipe shall be removed and replaced with suitable selected
materials as approved by the Owner/Consultant, properly compacted to provide
adequate support for the pipe.
During construction, the Bidder shall provide all protection for existing utilities and
services as may be required for his construction operations. Permanent protection of
certain items shall be as included under other sections or as instructed by the
Owner/Consultant.
In addition to the requirements as specified, herein the Bidder shall comply with the
following requirements:
a) Use all necessary precautionary and protective measures required to maintain existing
utilities, services and appurtenances that must be kept in operation. In particular, the
Bidder shall take adequate measures to prevent undermining of utilities and services
presently in services.
b) Protect existing or new utilities and services where required by the Bidder’s operations
and/or as directed by the Owner/Consultant. The Bidder shall be responsible for bracing
and supporting utilities and services to prevent settlement, displacement or damage.
The Bidder shall use all means necessary to control dust on roads, construction areas
and borrow pits.
Surfaces shall be regularly watered to prevent dust becoming a nuisance for the public
and interfering with the proper execution of the works.
This division applies to the methods and techniques of ground water control. Prior to
the decision for the method and technique to be applied, a comprehensive knowledge of
the soil and ground water conditions have to be obtained from the results of the soil
investigation and/or information given in writing by the Owner/Consultant.
Vol. – VA CIVIL WORKS Page 27 of 54
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All costs for ground water control for keeping the construction pits dry shall be
included in the scope of the bidder except otherwise indicated.
The method and technique shall be based on the IS: 3764.
The scope of supply includes the installation of all equipment, plants, pipes, machinery,
etc. and its removal after completion including operation & maintenance of the
equipment during the construction period.
Where necessary, cofferdams, sheet piles, pump sumps, equipment and channels,
troughs, inlet gutters, pipes, well points and any other works required for the water
control and discharge shall be part of the scope of supply. The dewatering system shall
be designed and installed in such a way that alterations and extensions can be made at
any time throughout the operating time, if necessary. Reserve units shall be kept ready
for service when failure of any of the installed units occurs.
The Bidder has to consider the possibility of a temporary failure of any pump, diesel
engine and/or the electric power service and shall install emergency power units with
sufficient capacity to feed the necessary power to the installed unit at the moment of
failure. The Bidder shall submit to the Owner/Consultant, the detailed method of the
envisaged pumping system for dewatering, the pump capacity and the standby reserve
units. The Bidder shall adjust the system if required by the Owner/Consultant.
The Bidder must ensure that any dewatering works will not cause any interference to
his own work and to those of other Bidders working elsewhere on site or at structures
under construction. Any damage occurring during the above mentioned period should
then be made good by the Bidder at his own expense.
During the foundation works, the excavated areas, foundation levels, and pits are to be
kept free of water down to at least 0.50 m below the foundation level.
01.13.15 Equipment
All equipment, instruments, machineries, tools, pipelines, etc. required for execution of
the water control shall be kept in good working condition throughout the operation
period.
01.13.16 Execution
The Bidder shall keep records of all data of importance occurring during operation of
the water control system. The records shall be submitted to the Owner/Consultant for
information and checking every working day. For that purpose, the lowering of the
water table shall be controlled by piezometers. The numbers and position of them shall
be submitted to the Owner/Consultant’s approval. The Bidder shall provide and
maintain these piezometers at his own expenses during the dewatering works or as long
as the Owner/Consultant requires it.
Pump operations shall not be stopped nor pipes, channels and equipment for dewatering
and water control removed or altered in any way, except with the express permission of
the Owner/Consultant. The Owner/Consultant will stipulate the time of removal. Until
then, the pumps and water drainage facilities shall be kept in proper working order
without extra payment being granted.
Provision of pump sumps and channels of the dimensions required for each particular
case shall include all necessary excavation of any kind of soil above and under water,
backfill and consolidation, sheeting, bracing, stiffening, sealing, scaffolding accesses,
as well as the disposal of water and all auxiliary works.
Routing of channels or pipes for discharge water shall be such as not to impede or
obstruct any of the other works and/or operations.
The same shall be applicable for pump sumps. Prior to the determination of any
arrangement of pump sumps, the Owner/Consultant’s approval shall be obtained.
Routing and location of water discharge lines shall be submitted to the relevant
authorities and to the Owner/Consultant’s approval.
The Bidder shall consider all difficulties and additional work due to the presence of
unexpected ground water during subsequent construction work. Where it is possible to
keep off or divert such water without special dewatering arrangements or where work
can be carried out normally under or in water, such a
method may only be applied after approval from Owner/Consultant has been obtained.
The Bidder shall maintain ready for service and regularly clean all dewatering
equipment and accessories and shall keep all access clear so that they can safely be used
without risk of accident. Any recommendations made by the Owner/Consultant in this
matter shall be carried out immediately.
Leakage:
Blockouts and pipe connections through structures and their closure, proper grouting of
joints, etc. or repairs in the event of leakage shall be the responsibility of the Bidder.
Piezometers:
a) General
The control of working and tests operations shall be carried out by the Bidder in the
presence of the Owner/ Consultant.
The Bidder shall prepare sheets for statistical analysis of the field and laboratory tests,
and shall submit the sheets to the Owner/Consultant for approval. Controlling will
consist of field and laboratory tests, such as compaction and density tests, grain size
distribution and shear tests.
If not otherwise specified under relevant items, the following min. tests have to be
carried out:
One (1) test analysing the ingredients of the water used for performance of the work.
Three (3) tests for specific gravity of soil as per IS: 2720.
One (1) test for bearing capacity of soil for static load as per IS: 1888.
Three (3) tests for grain size analysis of soils, if “Replacement of Material” is required
as per IS: 2720.
Three (3) tests of density of soil in place of sand cone method for each second layer of
“Backfilling and/or Replacement of Material and/or Roadwork” are required as per IS:
2720.
All tests shall be recorded in forms acceptable to the Owner/Consultant.
Tests shall be performed for each 500 m3 of fill but not less than once per shift.
As fill or backfill within the limits of the structure/building and below basement floors
as shown on the drawings to bring the sub-grade up to the required elevation or for
filling or backfilling against foundations walls and around footings.
As fill beneath grade slabs or basement floors either to bring local low areas to grade or
to replace disturbed or unsuitable soil. Place select fill in approx. 15 cm layers
(compacted thickness) and compact to 98% of maximum dry density (IS: 2720).
Quality control shall establish all of the following values:-
Unit dry weight
Standard penetration test: 20 blows per 10 cm penetration.
Plate load test as per IS: 1888.
Ordinary fill, as specified herein above, is required for all fill and backfill where special
fill or select fill have not been specified on the drawings. Place ordinary fill in 15 cm
layers (of compacted thickness) and compact to 95% of maximum dry density at
optimum moisture content as per standard Proctor Density Test.
01.14.01 General
structures, trenches, pits, etc. shall be designed as per latest relevant IS codes in general.
Construction in general shall follow provisions of IS: 456 and IS: 3370 for normal and
water retaining structures respectively.
General
All designs of RCC structures shall be carried out by limit state method as per IS: 456
unless use of working stress method is specifically mentioned. Design strength of
materials and design loads shall be calculated using appropriate partial safety factors
over characteristic strength and characteristic loads as per IS: 456.
IS: 11384 shall be followed for design of steel concrete composite beams. For
reinforcement detailing IS: 5525, SP: 34 and IS: 13920 shall be followed.
The walls shall be provided with reinforcement on both faces for sections 150 mm or
more, even if not required from design consideration.
Joints are to be arranged in such a way that stresses and strains caused by shrinkage,
settlements, temperature, differential settlement, etc. do not adversely affect the
structures. This primarily applies to differently loaded areas and structures having
different foundations or foundations of different depths. The settlement joints shall run
through the complete structure down to foundation level, the expansion joints however
shall stop on the top level of foundations.
The joint width is to be planned considering all relevant factors (settlements, tilting,
movements, aspects etc.).
01.14.05 Replacement
If unsuitable soils are encountered below the grade slabs or basement floor, they are to
be replaced by suitable layer wise compacted material down to the good bearing soil.
Materials and compaction method as well as quality control are described in clause
‘Earth and Rockworks’ of this section. Selected fill is to be employed below all grade
paving and basement floors.
RCC water retaining structure like storage tanks shall be leak proof and designed as un-
cracked section in accordance with IS: 3370 (Part 1 to IV) by working stress
method/Limit state method. However the parts of such structures not coming in contact
with liquid may be designed according to IS: 456.
All water retaining / storage structures shall be designed assuming liquid upto the full
height of wall irrespective of provision of any over flow arrangement. No pressure
relieving devices shall be permitted in underground structures.
In all liquid retaining structures, PVC water bar shall be provided at each construction /
expansion joint. The sequence of construction shall also be specified on drawings
showing construction joints.
The walls shall be designed for a surcharge load of 2000 Kg/m² or actual whichever is
higher.
Liquid Retaining Structure shall be checked for two loading conditions. With water
inside up to operating level and no earth fill outside or water in one compartment and
no water in the other compartment (where two compartments are provided).
Base slab / raft of all liquid retaining structure shall be designed to withstand the uplift
pressure in tank empty condition.
In general tank foundations shall be circular type ring foundations provided along the
periphery of the tank. Inner side of the ring foundation shall be filled with well
hydraulically compacted clean river sand, in 500 mm thick layers, over this next layer
shall be 150 mm thick PCC (M-10), over this 50mm thick anti-corrosive layer of screed
coarse sand mixed with 8% to 10% of bitumen by volume and compacted over this next
layer is 50 thick pre-mix carpet in two layers of 30mm and 20mm respectively with 12
mm and down broken stone chips and 80/100 grade bitumen at 52 kg/cum. Design of
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the foundation shall be as per Limit state method. Follow other details provided under
clause 7.0 above.
General
The design of machine / equipment foundation shall be as per IS: 456 and IS: 2974. The
provisions of DIN 4024 may also be followed for machine foundations. All machine /
equipment foundations and structures subject to vibrations shall be suitably
proportioned so that amplitude and frequency of the foundation / structures are within
permissible limits.
Dynamic analysis shall be carried out to calculate natural frequencies in all modes
including coupled modes and to calculate vibration amplitudes. Frequency and
amplitude criteria as laid down by the relevant codes or machine manufacturers shall be
satisfied. Minimum reinforcement shall be governed by IS: 2974.
For the foundations supporting minor equipment weighing less than one ton or if the
mass of the rotating parts is less than one hundredth of the mass of the foundation, no
dynamic analysis is necessary. However, if such minor equipment is to be supported on
building structures, floors, etc. suitable vibration isolation shall be provided by means
of springs, neoprene pads, etc. and such vibration isolation system shall be designed
suitably. All such foundation shall be separated from adjoining part of building and
other foundations. Joints at floor/ slab shall be suitably sealed. All appendages to such
foundations shall be reinforced suitable to ensure integral action.
Loads
All static and dynamic forces / loads which equipment supplier considers applicable
shall be considered for analysis and design of machine foundations.
Foundation Sizing
The outline plan dimensions of foundations as given by the machine supplier will be
adopted. The height of foundation will be selected after taking into consideration soil
strata and operating level of the machine. The eccentricity of common CG of machine
and foundation with respect to the centroid of base area should not exceed 5 % of the
corresponding base dimensions of foundation. Partial contact between the foundation
and soil strata shall be considered wherever applicable. The footing will be checked for
minimum contact area of 80 % and maximum bearing pressure will be calculated for
the actual contact area only.
The minimum grade of reinforced cement concrete shall be M30, unless specified
otherwise.
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The analysis and design of machine foundations will be carried out to ensure the
following:
Compliance with the manufacturer’s requirements and relevant standards
No resonance phenomenon of a disturbing nature to machine operation should exist at
the normal running speed
Calculations to be performed for dynamic as well as static cases for reinforced concrete
block type pedestal
Soil bearing capacities
Deep foundation capacities
Lateral earth pressures
Allowable settlements
Structure, equipment and environmental loadings
Equipment performance criteria
Access and maintenance requirements
Temporary construction loadings
The foundation will be designed for the most critical combinations of forces and
moments, resulting from all possible combinations of the various loading from the
equipment system. The foundation sections will be sized and reinforced adequately for
bending moments and shear stresses and uplift.
The foundation shall be checked for overturning, sliding and uplift as per relevant IS
Codes. The foundation will be checked for overturning with minimum and maximum
vertical loads.
For analysis of machine foundation following data will be furnished by the equipment
manufacturer:
Loading diagram showing static and dynamic loads and points of application of loads
Operating speed of machine
Weight of rotating parts, maximum eccentricity of rotating mass from the geometric
axis of rotation
Location of C.G. of machines in all three axis
Mass moment of inertia
Allowable amplitude / velocity of vibration at machine bearing points
Temperatures at various areas during operation
All dynamic foundations shall be isolated from building foundations. The isolation gap
shall be of minimum 25 mm.
Natural frequencies of structures and components shall be away from running speed of
equipment by at least 20 % and preferably 50%
For design of foundation of large fans etc., provision shall be kept in the foundation for
addition of mass / area for retaining of the foundations if required at a later date
However following minimum factor of safety shall be followed:
Factor of safety against overturning due to wind, seismic or other lateral loads shall be
1.5
Factor of safety against sliding shall be 1.5
Factor of safety against uplift due to hydrostatic forces shall be 1.2 and due to any other
loads shall be 1.5. Uplift check shall be carried out during construction stage also.
All block foundations resting on soil shall be designed using the Linear weightless
spring method(Barkan method) as per IS 2974.Alternately, Elastic half space theory can
also be used by referring to specialized literature. The mass of the RCC block shall not
be less than three times mass of the machine. Dynamic analysis shall be carried out to
calculate natural frequencies in all modes including coupled modes and to calculate
vibration amplitudes. Frequency and amplitude criteria as laid down by the relevant
codes or machine manufacturers shall be satisfied. Minimum reinforcement shall be
governed by IS: 2974.
The temperature of fresh concrete shall not exceed 25C when placed. For maintaining
the temperature of 25C in the top decks of machine foundations, crushed ice shall be
used in mixing water.
Design shall be checked against buoyancy due to the ground water during construction
and maintenance stages for structures like underground storage tanks, pits, trenches,
basements, etc. Minimum factor of safety of 1.2 against buoyancy shall be ensured
considering empty condition inside and ignoring the superimposed loading. For the
purpose of calculating downward load due to any overburden, only the mass located
vertically above the projected area of the base slab shall be taken in to consideration.
Maximum 500mm widening/Extension/projections all around in foundation to take
advantage of soil weight in uplift check is permissible.
All building sub-structures including pump houses shall be checked for sliding and
overturning stability during both construction and operating conditions for various
combination of loads. Factor of safety for these cases shall be taken as mentioned in IS:
456 and other latest relevant IS codes. However following minimum factor of safety
shall be followed:
Factor of safety against overturning due to wind, seismic or other lateral load shall be
1.5 minimum
Factor of safety against sliding shall be 1.5 minimum
Factor of safety against uplift due to hydrostatic forces shall be 1.2 and due to any other
loads shall be 1.5
Stability of the structure shall also be investigated for loading conditions during
construction, repair or other temporary measures. Lower factor of safety may be used
for such loading conditions as per relevant IS codes.
In cases where dead load provides the restoring force, only 0.90 times characteristic
dead load shall be considered. Imposed loads shall not be considered as restoring force.
From fire resistance point of view minimum cover to reinforced concrete members shall
be as per Table 16A of IS:456.
Mix Design
At the commencement of the contract the Bidder shall make preliminary tests to
determine the proportions by weight of cement, fine aggregates, coarse aggregates and
water necessary to produce required grades of concrete. The mix proportions shall be
selected to ensure that workability of the fresh concrete is suitable for the conditions of
handling and placing and when concrete hardens, it shall have the required strength,
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durability and surface finish. The Bidder shall get approval of Owner/Consultant to
such proportions before he starts concreting. However, such approval shall not relieve
the Bidder of his responsibility to produce concrete having compressive strengths as
laid down in the foregoing Table.
No departure from the approved proportions will be permitted during the works unless
and until the Owner/Consultant gives written authorisation for any change in
proportion. The Owner/Consultant shall have authority at any time to check whether the
mixing of concrete is being carried out according to the approved proportions.
For the all major and important R.C. works and for all special works, the design of
mixes shall be made by the Bidder at his own cost, for each grade of concrete as well as
for various workability. The design of mixes shall be made according to I.S. 10262 or
any other approved standard methods.
The concrete made by designing the mix is termed hereinafter as "Design Mix
Concrete".
The cement content for various grades of concrete shall be based on design mix.
Minimum cement content shall be as per table 5 of IS 456.
Where a particular water cement ratio is stipulated in the design or drawing along with
the characteristic grade of concrete the design of mix shall be carried out by adjusting
the other variable factors to obtain the characteristic strength of concrete with stipulated
water cement ratio.
In the structures where the impermeability and shrinkage of concrete have an important
bearing on the durability and serviceability of the structures, such as water retaining
structures, basements, underground premises, tunnels, pump houses, pre-stressed
structure, thin precast members etc. the water cement ratio shall be kept low and
preferably not exceeding 0.45.
The water cement ratio, as achieved in the Mix Design, or as specified in the drawings
shall be adhered to strictly and shall not be varied without the permission of the
Owner/Consultant.
iii) Workability
The workability of fresh concrete shall be such that the concrete is just suitable for the
conditions of handling & placing so that after compaction if becomes completely
consistent and homogeneously surrounds all the reinforcement and completely fills the
formwork.
Normally, in the condition of low water cement ratio as well as for medium/high
workability, the workability shall be achieved by increasing the cement content, in
consistent with added water.
In cases where the cement content is to be limited to reduce the heat of hydration, and
the water/cement ratio is also to be kept low to reduce the permeability or due to other
requirements the desired workability may be achieved with use of limited doses of
plasticiser orair entraining agent. In such cases the method of mixing and dosage of the
plasticiser/air entraining agent shall be according to the manufacturer's specification
and with the approval of the Owner/Consultant.
The usual limits of consistency for various types of structures are given below:
Note: Not withstanding anything mentioned above, the slump to be obtained for work
in progress shall be as per direction of the Owner/Consultant. With the permission of
the Owner/Consultant, for any grade of concrete, slump shall be maintained with the
usage of Plastisizers/ Superplasticizers as per the requirement. No extra payment will be
made for this addition.
v) Durability
Minimum fire rating of 2 hours shall be considered where fire hazard is expected and
accordingly minimum cover shall be taken as per Table 16 A of IS: 456. For structures
below ground level which are exposed to sulphate attack, requirement of cement shall
be as per Table 5 of IS: 456. Intermixing of different grades of concrete in the same
structure shall not be allowed in a particular element.
Mix design concrete shall be used for all areas other than plain concrete work used for
lean concrete, screeds and backfill.
The following minimum grades of concrete as per IS: 456 shall generally be used for
the type of structures noted against each grade.
Table 2.7
Grades of Concrete
Concrete
Type of structure
mix/Grade
M10 Fill concrete
1:4:8 Blinding layer below foundations, trenches and underground
structures, foundation below brick wall, etc.
Minimum thickness of layer shall be 75 mm
1:2:4 For screed layer below water retaining structures.
M20 Plinth protection work around buildings
M25 Encasement of structural steel work, all PCC paving work,
M25 All RCC structures and equipment foundations, super structure,
grade beams, columns, roof slabs and all underground RCC
structures, cable and pipe rack foundation, pedestals, cable and pipe
trenches etc. water retaining structures below and above ground,
mill foundations, ground floor slabs, precast concrete work etc.
M-30 Water retaining structures
M-40 RCC road
The amount of material passing a 75 micron sieve (IS test sieve) shall not exceed the
following limits:-
The amount of hollow shells like to form voids or remain partially unfilled and present
in material retained on an IS 2.36 mm sieve, determined by direct visual separation,
shall not exceed 3% by weight of the entire sample.
Fine aggregate shall not contain appreciable amounts of flaky and/or elongated
particles.
The water absorption of fine aggregate, determined in accordance with BS 812 shall not
exceed 2.0% by weight.
Fine aggregate subjected to five cycles of the soundness test, specified in IS: 2386
(Part-5), shall not show a loss exceeding 10% when sodium sulphate solution is used
and 15% when magnesium sulphate solution is used, except where approved otherwise.
Tests are to be executed in accordance with IS: 2386. The grading of fine aggregate for
concrete work shall comply with the requirements of IS: 383.
The grading of the aggregates should be such as to produce a concrete of the specified
proportions, which shall work readily into position without segregation and without the
use of excessive water content. The grading should be controlled throughout the work
so that it conforms closely to that used for the preliminary tests.
A check on the moisture content of sand should be made at least once a day before
concreting. The amount of water to be added to the concrete mix should be adjusted
accordingly. Any washing, screening, classifying and other operations on the fine
aggregate required to meet this specification shall be done by the Bidder. Washing is
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Sand for masonry mortar shall conform to IS 2116 and sand for plaster shall conform to
IS 1542. Sand when used as fine aggregate in concrete shall conform to IS 383. For
filling medium, grained sand (having fines less than75 microns not exceeding 20%)
shall be used.
Fine Aggregate (M-Sand) : Aggregate smaller than 4.75 mm and within the grading
limits and other requirements set in IS:383 (latest revision) is termed as Fine
Aggregate or Sand. Only Fine Aggregate from approved sources and conforming to
the above IS Specification shall be allowed to be used on works.
In case of unavailability of normal specified river sand the M sand or Crushed stone
sand shall be used with the approval of the Owner /Consultant as per given
criteria/specifications below .
i) As per Cl. 3.1.4 , of IS-383 (latest revision) the terminology of M-sand (manufactured
sand) as defined as fine aggregate manufactured from other than natural sources , by
processing materials using thermal or other processes such as separation, washing,
crushing and scrubbing. Generally the M sand or Crushed stone sand for the fine
aggregate are produced by crushing the hard stone.
The Crushed stone sand or M sand conforming to the following shall only be used as
fine aggregate in making concrete for sub and superstructures.
The Crushed stone sand is to be manufactured using VSI crushers only and not with
HSI crushers. In order to remove the fines , Crushed stone sand manufacturer should
have mechanized washing facility unit. Crushed sand stone conforming to Grading zone
–ll as per IS-383 (latest rev.) shall only be used. The M sand shall comply all the
parameters and recommendations of IS: 383 (latest rev.)
ii) The M sand shall be used only after the following tests are to be conducted by the
bidders at the NABL accredited laboratories with proven track records of performing
such type of tests by sending sealed samples of the materials -
a) Gradation Test.
b) Petrography.
c) Silt content.
d) Permeability test.
e) Adulteration test.
f) Design Mix Report.
g) Chemical Analysis Report
Using of M-Sand/Crushed Stone Sand based on the Test reports shall only be done after
written approval of Engineer –In-Charge.
iii) The Crushed stone sand in general shall not be used for the following
structures/facilities :-
The structures where the slip form construction is envisaged the M sand or Crushed
stone sand may be used for casting its foundations only as they are not constructed
using slip form Technology.
c) Special care for design mix, cement content and necessary curing in the initial stage
shall be taken care of while using M sand /Crushed stone sand. However if the results
are not satisfactory , the use of crushed stone sand shall not be allowed for all RCC
floor slab upto and including 150 mm thickness, which are directly exposed to the
atmosphere immediately after casting. In such cases the ordinary river sand shall be
used.
Aggregates smaller than 4.75 mm and within the grading limits and other requirements
set in IS-383 (latest rev.) as termed as fine aggregate . Only fine aggregate from
approved sources and conforming to IS- 383 (latest rev.) shall be used for execution.
The bidder shall have well developed site laboratory and quality control team to take
extra care while manufacturing and casting concrete using M sand/ Crushed stone sand.
Normally, any particular structure shall be constructed by using any one type of sand
(fine aggregate) only as per the direction / approval of engineer-in-charge. In general, it
is not permitted to use different types of sand in any particular structure.
Stone chips shall be used as coarse aggregate. It shall be crushed or broken from hard
stone obtained from approved quarries of igneous or metamorphic origin. The stone
chips shall be hard, strong, dense, durable and angular in shape. It shall be free from
soft, friable, thin, flat, elongated or laminated and flaky pieces and free from dirt, clay
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lumps, and other deleterious materials like coal, lignites, silt, soft fragments, and other
foreign materials which may affect adversely the strength & durability of concrete. The
total amount of deleterious /foreign materials shall not exceed 5% by weight according
to relevant clause of IS: 383-1970. If found necessary the stone chips shall be screened
and washed before use.
01.15.03 Cement
Ordinary Portland cement / Portland slag cement complying with the requirements of
IS:269-2015 and I.S. 455-2015 respectively shall be used for making plain and
reinforced concrete, cement grout and mortar.
Other types of cement may be used depending upon the requirements of certain jobs
with the approval of the Engineer. These shall conform to the following standards :
Testing of samples:
The Contractor shall supply a copy of the manufacturer's test certificate for each
consignment of cement supplied by him and consignments shall be used on work in the
order of delivery. The Contractor shall supply samples of cement to the Engineer as
frequently as he may require for testing. The sampling of cement for testing shall be
according to IS: 3535-1986. All tests shall be in accordance with the relevant clauses of
IS: 4031 (Part-I to Part-15) 1988 to 1991 & IS: 4032-1985.
Contractor's responsibility:
From the time a consignment of cement is delivered at site and tested and approved by
the Engineer until such time as the cement is used on the works, the Contractor shall be
responsible for keeping the same in sound and acceptable condition and at his expense
and risk. Any cement which deteriorates while in the Contractor's charge and is
rejected as unsuitable by the Engineer, shall be removed from the site to outside the
limits of work at the cost of contractor within two days of ordering such removal by the
Engineer.
Stock of cement:
In order to ensure due progress, the Contractor shall at all times maintain on the site at
least such stock of cement as the Engineer may from time to time consider necessary.
No cement shall be used upon the works until it has been accepted as satisfactory by the
Engineer.
Storage of cement:
The cement shall be stored in such manner as to permit easy access for proper
inspection and in a suitable weather-tight, well ventilated building to protect it from
dampness caused by ingress of moisture from any source. Different types of cement
01.15.04 Water
Water used for mixing concrete and mortar and for curing shall be clean and free from
injurious amounts of oil, acid, alkali, salts, sugar, organic materials or other substances
that may be deleterious to concrete or steel. The pH value of water shall generally be
not less than '6'. Water has to meet the requirements mentioned in clause 4.3 of IS:
456-1978. Water shall be obtained from an approved source.
Where it is obtained from a source other than a supply main, it shall be tested to
establish its suitability. Water for construction purpose shall be stored in proper storage
tanks to prevent any organic impurities getting mixed up with it.
Approval
Admixtures to concrete shall not be used without the written consent of the Engineer.
When permitted, the Contractor shall furnish full details from the manufacturer and
shall carry out such test as the Engineer may require before any admixture is used in the
work.
Types
Admixtures used as integral water proofer shall be free of chlorides and sulphates and
shall conform to IS: 2645-2003. The application and doses shall be as per
manufacturer's specification.
The routine tests of materials, delivered at site, shall be at the following intervals:
Water - Once in two months for each source of supply and in other
respects generally as per IS : 456-2000.
01.15.06 Steel
For Reinforcement
Reinforcing bars for concrete shall be round steel bars of the following types as may be
shown on the drawing:
i) Plain mild steel bars conforming to Grade-I of IS : 432 "Mild Steel & Medium Tensile
Steel for Concrete Reinforcement".
ii) High strength deformed steel bars/TMT bars conforming to IS : 1786 for Concrete
Reinforcement.
iii) Reinforcement fabrics conforming to IS:1566 "Hard Drawn Steel Wire Fabric for
Concrete Reinforcement"
All reinforcement bars shall be of uniform cross sectional area and be free from loose
mill scales, dust, loose rust, coats of paint, oil or other coatings which may destroy or
reduce bond. Unit weight of reinforcement bars conforming to I.S. 1786 is as given
below.
6 0.222
8 0.395
10 0.617
12 0.888
16 1.580
18 2.000
20 2.470
22 2.980
25 3.850
28 4.830
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32 6.310
Binding wire
Binding wire for reinforcement shall be annealed steel wire 20 BWG conforming to IS :
280 -2006 "Specification for Mild Steel Wire".
Steel for light structural work and for preparation of inserts and embedments shall
conform to IS: 2062-2011 "Steel for general structural purposes - Specification."
Steel Tubes
Steel tubes for use in light structural work and inserts shall be of light or medium class
(as may be specified in drawings or the schedule of items) and of grade YST 25
conforming to IS : 1161 - 2014"Specification for Steel Tubes for Structural Purposes".
Foundation Bolts
Nuts and locknuts shall conform to IS : 1363 (Part 1 to 3) -2018 "Specification for Black
Hexagon Bolts, Nuts and Lock Nuts (Diameter 6-39 mm) and Black Hexagon Screws
"Specification for Hexagon Bolts and Nuts (M-42 to M-150)".
Plain washers shall conform to IS : 2016 "Specification for Plain Washers and spring
washers shall conform to IS : 3063 "Spring Washers for Bolts, Nuts & Screws".
Steel tubes for non-structural use shall conform to IS : 1239 (Part-I) "Specification for
Mild Steel Tubes, Tubular and Other Wrought Steel fittings, Part-I : Mild Steel Tubes".
Fittings for steel tubes used for non-structural purposes shall conform to IS : 1239 (Part-
II) "Specification for Mild Steel Tubular and Other Wrought Steel Pipe Fittings".
Threaded Fasteners
Bolts and nuts for fastening shall conform to IS:1367 (Part 1)-2014 "Technical Supply
Conditions for Threaded Fasteners".
Testing
Test certificates from manufacturer shall be submitted for each consignment. Any
additional test which the Engineer may require shall be done according to IS : 1786,
1566, 280, 2062, 1161, 3063, 1239 (Part 1 and 2) and 1367.
Cast Steel
Quality
Cast steel shall conform to IS : 1030 "Carbon Steel Casting for General Engineering
Purpose". Unless otherwise specified, it shall conform to Grade2.
Conduits
Rigid steel conduits for electrical use shall conform to IS : 9537 (Part 2) for rigid pipes
and to IS : 3480 for flexible conduits. Fittings for conduits shall conform to IS : 2667.
All conduit pipes shall be finished with galvanised or stove-enamelled surface. All
accessories shall be of threaded type and pipes shall be jointed by means of screwed
couplers only. Bend in conduits shall be made to the dimension shown in drawing, but a
minimum of 12 times the diameter. Where shown in drawing they shall be treated with
anticorrosive preservative as specified.
Non-metallic conduits for electrical use shall conform to IS : 9537 (Part 3) -1983 for
rigid pipes. Fittings shall conform to IS : 3419-1989.
Bends shall be achieved by bending the pipes by inserting suitable solid or inspection
type normal bends, elbows or similar fittings.
230 mm thick fly ash brick wall with 1:6 Cement- Sand mortar. All non load bearing
Brick work as mentioned in this document shall be with Fly Ash Bricks unless noted
otherwise. Chamber burnt clay bricks shall be used for any non load bearing brickwork
in case of non-availability of Fly ash bricks, subject to the approval of MTPS-I.
Fly Ash Bricks :The Fly Ash Bricks shall conform to IS 12894. The dimensions of the
Flyash bricks shall be 190x90x90mm. Visually the bricks shall be sound, compact and
uniform in shape free from visible cracks, warpage, flaws and organic matter. The bricks
shall be solid and with or without frog on one of its flat side. Fly ash shall confirm to IS
3812.
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Note : Fly ash bricks shall be operated only for non-load bearing walls
Sand : Deleterious materials, such as clay and silt in the sand shall preferably be less
than 5%.
Additives : Any suitable additive considered not detrimental to the durability of bricks
may be used.
The successful bidder shall submit Field Quality Assurance plan for Civil, Structural
and Architectural works for approval of Owner /Owner's consultant.
The Bidder shall provide a site laboratory with equipment and shall maintain and
engage qualified technical personnel at site to run the laboratory for routine test at his
own cost and to ensure quality of construction and testing of all materials and works
conforming to specifications.
All defective materials / works which do not conform to the specifications shall be
rejected / dismantled and removed from site by the Bidder at his own cost.
For those tests which are not possible to be carried out at site laboratory, Bidder shall
arrange to send requisite samples to approved laboratory outside the site and get those
tested as required entirely at his cost.
Before starting any concreting or erection work at site, the stage passing certificates
have to be obtained from the engineer in the formats prepared after mutual discussion
and agreement.
Before covering up any work within excavated pits, clearance has to be taken from
engineer in respect of completion of said works as per drawing and specification.
01.17 Safety
The Bidder shall ensure that the safety requirements are met in respect of men,
materials, adjoining structures, equipment etc. and shall be totally responsible in case
any mishap occurs due to negligence or otherwise. In this connection the bidder shall
strictly adhere to the rules norms and regulations as applicable. The successful bidder
shall collect safety rules from the client. The successful bidder shall strictly adhere to
the safety regulations mentioned therein. The penalties for violation of safety norms as
per MTPS-I stipulations are applicable. To ensure effective enforcements of the rules
and requirements relating to safety protection arrangement made by the bidder shall be
open to inspection by MTPS-I.
In case of complicated work like deep excavation, intricate shuttering and formwork,
excavation in loose soil and below water table, stacking of excavated earth etc., work
plan with necessary drawings and documents have to be prepared by the Contractor and
got approved by the Engineer.
Necessary reference shall be made to the following Indian Standard Codes on safety
requirements for various type of work.
Safety requirements for Civil works provided in latest IS Codes shall be referred and
adhered to.
a) Architectural design
The Bidder shall adhere to the norms and basic schemes indicated in the Technical
Specification. The Bidder shall submit all catalogues/specifications for various floors
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and wall finishes, painting, sanitary and plumbing fixtures and fittings, doors and
windows, etc. Architectural drawings shall be prepared based on approved General
Arrangement drawings of relevant system.
The design calculations for all the buildings and foundations miscellaneous structures,
all equipment foundations etc. shall be furnished. The design calculations shall include
static design calculations dynamic analysis for all important structures and foundation
subjected to impact, vibrations etc. induced by equipment and other external forces.
Building data sheet showing specifications of materials, design standards followed, load
data assumed including the loading on roof, walkways, different floors, bulk material
density, crane and hoist loading, wind and seismic loading, wind thrusts and vibration
considerations, deflection, rainfall and run-off data assumed and type of framework etc.
shall be furnished. Also, type of flooring, roofing and sheeting and type of construction
are to be indicated. The loading combinations and other design assumptions made in
design are to be furnished.
Methods to be followed for (a) waterproofing, (b) Corrosion protection (c) thermal
insulation of various areas to be submitted by bidder.
Measures required for the safety of the buildings and foundations.
Structural design /drawings shall be prepared based on Approved Architectural and GA
drawings and submitted accordingly for Owner’s approval.
The following shall be furnished by the Bidder along with design calculations:
- Scheme of loads.
- Result of analysis member forces in design calculation for corrective chosen based on
permissible stresses, deflection, natural frequency etc.
- All documents shall be submitted as per engineering sequence of document submission
(e. g. Foundation design drawings shall be submitted after approval of superstructure
Analysis, design and drawings). Documents with approved input data shall only be
submitted for Owner’s approval by the Contractor.
01.18.02 Drawings
The Bidder shall prepare general layout drawings giving salient levels and dimensions
of the whole area within the battery limits showing all over ground and underground
services and facilities, buildings, roadways etc. Detailed working drawings shall be
prepared on the basis of the general layout drawings considering overall foundation
layout for the equipment, building services etc., space requirement and clearances as
necessary. The Bidder shall ensure that no further drawing shall be required to be
prepared by any other agency for successful implementation of the project. The Bidder
shall submit a comprehensive and complete unit wise classified list of drawings.
The Bidder shall submit for approval or information as the case may be as per
classification given below , general arrangement and detailed working drawings for all
concrete, reinforced concrete and other civil works as follows:
d) Types, specification and details of doors, windows, louvers, floor finishes, roof
finishing, partitions, false ceiling, false floor, G.A. of toilet blocks etc.
e) Colour Scheme of all the buildings (For Owner’s approval).
f) Detail of partitions, expansion joints, counters/platforms, stair, balustrade, canopy,
chajja, parapet, gutter, down pipes etc.
g) Design calculations along with load data for buildings, foundation for equipment and
structures, auxiliary facilities etc.
h) Structural drawings for Civil buildings/framed structures, equipment foundations and
other foundations and structures showing dimensions of structural elements like slabs,
beams, columns, foundations etc.
i) Plan and sectional drawings with all dimensions and details for foundation of
equipment and structures, auxiliary facilities etc.
j) Reinforcement drawings with all dimensions and details for foundations of equipments
and structures, auxiliary facilities etc.
k) Design, Layout and sectional details of roads, road crossings, man holes, pits etc.
l) Design, layout and sectional details of drainage network with all invert levels, slopes,
sizes, dimensions, manhole top level etc.
m) Standard General Notes/Specifications.
a) Standard drawings
b) Soil Investigation Report
c) Layout and sectional details of sewage network with all invert levels, slopes, sizes,
dimensions, manhole top level etc
d) Bar Bending Schedule. However, Observations, if any, on compliance of
Reinforcement Area in R.C.C. drawings with respect to design calculations shall be
made.
e) Detail of bolts, inserts/embedment’s, coverings, hand railings, ladders etc.
f) Sanitary and plumbing detail drawings.
g) Rain water Harvesting report (approved by Authorised Govt. Agency)
Review category for any other drawings not mentioned in above two categories shall be
decided later considering their importance and utility for the project.
ANNEXURE - I
GEOTECHNICAL STIPULATION
01 Introduction
The bidder shall visit & carefully examine the site & surrounding, before
submission of bid, to acquaint himself about general site condition, terrain, existing
filling, depth of rock layer, accessibility, existing features, existing structures,
existing underground services and all other conditions & matters affecting the work
and build up his rates accordingly. Claims and objections due to ignorance of site
condition shall not be considered after submission of bid.
02 Sub-Surface
The sub-surface generally consists of a top Fill layer, followed by weathered rock
layer at reasonably shallow depth.In some locations, Virgin soil layer may be
observed below Fill layer & above weathered rock layer.The bidder shall consider
the general layout, level of Original Ground and final Terrace Level (TL) of
different structures. Accordingly, choice of foundation shall be made, as per
provision of this geotechnical stipulation. To get indicative idea of sub-surface
stratification, reference can be drawn from the findings in nearby ESP location at
unit-IV of MTPS-1, where, in a Trial Pit location, weathered rock layer has been
reportedat 1.65 m depth, underlying top Fill layer.However, Depth &/or Thickness
&/or Presence &/or Nature of different strata &/or Existing Ground Levels (EGL),
may vary within the battery limit of the package, for which no commercial
implication shall be entertained at any stage of the project. It is the responsibility of
the bidder to assess the rock depth of the subject package location, by suitable
means.
03 Choice of Foundation
i) Depending on design requirement &/or depth & thickness of different strata &/or
constructability aspect, either Open foundation or Pile foundation shall be adopted.
ii) Open foundation, either in Fill or Virgin Soil layer or in weathered / disintegrated
Rock layer, may be adopted for the proposed structures, conforming to design
requirement, following the recommended maximum limit of NABC stipulated
herein, satisfying the relevant provisions of section 03.A of this document.
iii) In case, the stipulated NABC of Fill or virgin Soil or Rock layer for Open
foundation, is found to be inadequate for particular structure &/or required depth of
Open foundation is found to be too deep from construction aspect &/or Open
foundation is not practically possible due to close proximity of adjacent
structure/slope &/or there is technological / functional / constructability
requirement for pile foundation &/or thickness of Fill below TL is more than 6.0 m
&/or provision/s of Open foundation under clause No. 03.A of this stipulation is
not fulfilled, then Pile foundation shall be adopted.
iv) Higher SPT ‘N’ value in Fill, wherever encountered, shall not be considered as
representative parameter of Fill layer.
v) For Design purpose, Ground Water Table (GWT) shall be considered at respective
TL.
03.A.02 In case, any localized soft / loose spot is encountered at founding level, the same
shall be replaced by PCC (M-10).
Design Bulk Density of Virgin soilor Fill shall be considered as 1.70 gm/cc.
In weathered Rock layer, encountered at varying depths within this site, Open
foundation shall be placed with an embedment not less than 600mm within such
layer, for which the maximum value of Net Allowable Bearing Capacity, shall be
limited to 30 ton/m2for any size of footing. However, with an embedment of at
least 1500 mm within weathered rock layer, the maximum value of Net Safe
Bearing Capacity shall be limited to 35 ton/m2for any size of footing.
There will not be any increase in Net Safe Bearing Capacity with depth, apart from
the above.
Precautionary measures for Safety of Foundation placed on rock layer, shall follow
the relevant clauses of Section 6, 7 & 8 of IS : 13063 - 1991.
Excavation aspects in Rock layer shall be considered by the bidder from their
Expertise / Experience, Methodology of rock excavation to be adopted, Type of
Equipment to be used, Capacity of Equipment to be used, Site Visit information,
Expert’s observation of rock found in natural & man-made excavation in & around
site, Information gathered from earlier excavations, Study of regional Geology and
any other required considerations for rock excavation. The bidder is solely
responsible for such assessment on excavability of rock layer at any depth. The
geo-engineering description of Rock Core specimen or any test parameter of
individual rock specimen shall not be treated as Rock Mass characteristics for
excavation purpose. No extra claim shall be entertained at any stage of work due to
type of rock encountered during excavation.
Penetration aspects in rock layer for rock-socketed pile, shall also be solely
considered by the bidder following the similar considerations furnished above for
rock excavation.
In case, Pile foundation is adopted, then Bored Cast-in-situ RCC (M-30) Pile shall
be used. The piles shall be bored cast-in-situ cylindrical type RCC piles of 500 mm
&/or 550 mm &/or 600 mm &/or 750 mm &/or 1000 mm diaterminated within
underlying specified weathered rock (& not boulder) layerwith a rock- socket
length not less than 4D (where D is the diameter of the pile) within such weathered
rock layer, to achieve the design capacity. Minimum center to center spacing
between adjacent piles shall be 2.5 D.
With stipulated rock-socket length within such rock layer, to achieve the design
capacity. Minimum center to center spacing between adjacent piles shall be 2.5 D.
The weathered rock for pile socketing shall be recognized by identifiable rock
texture/fabric in the bored material as well as by SPT ‘N’ > 100.
Lateral
Capacity 2.5 2.9 3.4 3.9 5.5 8.8
(ton)
For fully Free Head condition, the above capacities shall be reduced to one-third.
Maximum moment due to lateral load shall be evaluated as per Section C-4.3,
Appendix C, of IS : 2911 (Part-1/Sec 2) -2010. ‘Zf’ is the depth of fixity as
defined in the above code.
03.B.03 In case, Pile foundation is adopted, the enclosed Piling TS shall have to be
followed for the same.
TENDER SPECIFICATION
FOR
SEMI DRY FLUE GAS DESULPHURIZATION
(FGD) SYSTEM & ITS AUXILIARIES
MECON LIMITED
RANCHI – 834 002
TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
01 General
This specification covers the Piling work, required for the Installation of
F.G.D. System at MTPS-1 of Mettur Thermal Power Station of TANGEDCO,
Tamilnadu.
The bidder shall visit & carefully examine the site & surrounding, before
submission of bid, to acquaint himself about general site condition, terrain,
accessibility, existing features,underground utilities, existing structures, and all
other conditions & matters affecting the work and build up his rates
accordingly. Claims and objections due to ignorance of site condition shall not
be considered after submission of bid.
02.01 Codes
Any Standard / Code mentioned in this specification means its latest revision
including amendments, if any.
In case of any conflict between the requirement of this specification & those of
the referred codes / standards, the former shall govern.
02.02 Design
The piles shall be bored cast-in-situ cylindrical type RCC (M-30 grade) piles
not shallower than specified depth.
The Capacities of Pile (in Compression, Uplift, Lateral) for different diameter
Piles, terminated at different depths,are stipulated in the Geotechnical
Specification. Such stipulations will be binding to all turnkey bidders for
bidding, designing, engineering & execution of all pile foundations for this
package.
The contractor shall submit the reinforcement design of pile for approval of
TANGEDCO. Such structural design shall be based on pile capacities
specified in the Geotechnical Specification.The contractor need not submit any
calculation for evaluation of geotechnical capacity of pile.
02.03 Materials
All the materials proposed to be used, shall be free from any objectionable
substances, shallconform to the following stipulation & shall be approved by
TANGEDCO. Any testing required to prove the suitability of such materials
shall be carried out by the contractor at his own cost & in presence of
TANGEDCO. Any material rejected by TANGEDCO shall be immediately
removed from the site.
02.03.01 Reinforcement steel shall conform to High yield strength deformed bars of
grade Fe 415 as per IS:1786and for stirrups/links mild steel reinforcement
conforming to IS:432 may be used. For marine / coastal / corrosive
surroundings, corrosion resistant bars shall be used. Test certificate for
reinforcement steel shall be obtained from recognized agency, before using. If
the steel is purchased by the contractor, TANGEDCO may desire to check the
testing of the same and the contractor shall arrange it in an approved
laboratory at his own cost.Reinforcement shall be provided for full depth of
pile as furnished in the approved drawing.
02.03.02 Reinforced Cement Concrete for Piles shall be of Grade M-30 using 20 mm &
downgraded stone aggregates. The slump of concrete shall range between 150
mm to 180 mm. The water-cement ratio shall not exceed 0.5. To achieve the
specified slump using specified water cement ratio without compromising with
strength, suitable plasticiser, if required, may be used at no extra cost, subject
to approval of TANGEDCO. If concentration of Sulphate (measured as SO3)
exceeds 0.5% in soil or 1200 ppm in ground water, sulphate resisting cement
shall be used.
02.03.04 The physical properties, mechanical properties & gradation of coarse & fine
aggregate shall follow IS:383. Testing of aggregate properties (if desired by
TANGEDCO) shall follow relevant parts of IS:2386.
02.03.05 Water used for concrete shall be clean & free from injurious amount of
harmful substances in such amounts that may impair the strength & durability
of pile concrete. Generally potable water shall be considered satisfactory. In
case of any doubt felt by TANGEDCO about the quality of water, contractor
has to prove that the concrete prepared with proposed water shall not have a
compressive strength lower than 95% of the strength of similar concrete
prepared with distilled water.
02.03.06 Preliminary mix design shall be done in accordance with IS:10262& SP:23
subject to approval of the customer. Cube tests, slump test & other relevant
tests for preliminary mix design and Routine cube test, slump test for regular
concreting shall be carried out at site / site laboratory at contractor's own cost.
Concrete cube tests shall be done as per IS : 516. The calibration certificate
(not older than one year) of the testing machine shall be available at site. If
TANGEDCO feels any doubt about the calibration, the contractor has to check
the same at an approved laboratory at his own cost. All such tests shall be
conducted in presence of TANGEDCO. At least one set (3 cubes for 7 days &
3 for 28 days strength) of cube shall be tested for every 5 piles or at any
deterioration in concrete quality if felt by TANGEDCO, whichever occurs
earlier.Slump tests (apparatus conforming to IS:IS:7320) shall be carried out at
least once for each pile or more frequently, if desired by TANGEDCO.
The equipment & accessories should be compatible with the type of deposit,
method of installation, type of founding strata & required penetration in the
founding strata.
02.05 Construction
02.05.02 (A) In areas, where heterogeneous Fill & other industrial wastes are encountered,
Boring shall proceed by driving suitable Bailer - Chisel, extracting the bored
material with the boring tools & simultaneously advancing the casing
(temporary or permanent, as the case may be). The hard pieces shall be broken
by Chisel / Hard-face shoe of Bailer & shall be extracted by the Bailer. While
boring in soft material liable to cavitation, boring tools shall not be operated at
a level below the toe of the casing. The Care shall be taken to ensure that the
volume of water added to the bore shall be no more than the minimum
necessary for the operation of the boring tools. The temporary casing shall be
driven down through the soft material to penetrate a hard stratum not subjected
to cavitation and shall be sealed in this material as far as possible. Thereafter
the boring shall be continued by means of boring tools until the approved
bearing layer is reached.
02.05.02 (B) In areas, where piling is to be started right from virgin soil deposit, pile boring
may be done either by Bailer - Chisel method or by rotary boring with mud
circulation process. In rotary boring method, stabilisation of the side of
borehole can be done by the use of bentonite slurry. Either, Direct Mud
Circulation (DMC) or Reverse Mud Circulation (RMC) process shall be
adopted depending on soil condition & pile dimension. In such cases, the
bentonite slurry must be used at least from the level of sub-soil water, & the
hole should then be always kept almost full with the fluid. The density of
bentonite slurry shall be in the range of 1.05 to 1.12. During installation of
Trial piles, the exact density of bentonite to be used, shall be made specific
depending on site-condition. After standardization, the density of bentonite
slurry shall be maintained although the project & checked regularly at an
interval of 5 piles or at any change in its specified quality if felt by the
purchaser, whichever occurs earlier. Pressure of slurry pump shall be sufficient
enough to clear out all cuttings efficiently from the hole.
02.05.02 (C) Hydraulic rotary Piling rig can be used, for any type of areas mentioned above,
subject to its suitability.
02.05.03 At the last stage of boring or in intermediate hard layers chisel or chopper may
be used. The rate for piling work should be inclusive of any chiseling,
chopping of hard strata, clearing of bottom of pile bore hole etc. complete as
per specifications. The piles shall be installed with due consideration for safety
of adjacent structures by a method which leaves their strength unimpaired and
which develops and retains the required bearing resistance.
Proper precaution shall be taken to prevent any collapse of overlying soil due
to impact / vibration caused by chisel during penetration through hard stratum.
02.05.04 Reinforcement as required shall be made into stiff cages sufficiently welded to
withstand handling without any damage or distortion. Reinforcement shall be
placed immediately after cleaning and inspection of the bottom of bore holes.
The reinforcement should be supported away from the sides of the shaft by
means of suitable space block to ensure concentric alignment in the shaft.
Steps shall be taken to ensure correct positioning during concreting of
reinforcement in the piles without any distortion. The clear cover to main
reinforcement shall not be less than 50 mm.
02.05.05 Immediately before placing of reinforcement and concreting, the bored hole
shall be cleaned of all the loose material, debris and all the water shall be
removed. The pile tip zone shall be thoroughly cleaned by flushing the bore
with fresh Bentonite slurry to completely replace the old Bentonite slurry used
during the previous operations. This shall be carried out for 45 minutes in two
stages. Cleaning for initial 30 minutes shall be done before lowering of
reinforcement cage & final 15 minutes after lowering the reinforcement cage.
02.05.06 Concrete shall be so placed as to fill the entire volume of the tube or bore
without the formation of voids caused by the faulty consolidation or entrapped
air. Proper care shall be taken to ensure that the fluid alluvial soil does not
penetrate between batches of the concrete.
In case of cased holes, after the required founding level is encountered, the
bottom shall be sealed with concrete and the reinforcement cage shall be
lowered. If the borehole is dry, concrete shall be deposited in such a manner so
02.05.07 Concreting of Pile shall continue until the Pile is fully formed upto a level of
not less than 750 mm above cut-off level of piles. Extraction of casing
wherever used, shall be done in such a way, so that, no necking or shearing of
concrete in the shaft takes place. Pile length above cut-off level shall be
trimmed. Trimming of Pile top shall not be permitted before 7 days of
concreting in case of mechanical chipping & not before 3 days concreting in
case of manual chipping.
02.05.08 The concreted length of piles shall be measured from the toe of pile to cutoff
level of pile.
02.05.09 Temporary stoppage of work may be permitted only during boring stage.
Thereafter right from boring or chiseling of final portion of pile length through
subsequent activities of flushing, lowering of reinforcement cage, lowering of
tremie, pre-concrete flushing &upto concreting of full pile length, no halt
whatsoever in the execution of work shall be permitted.
02.05.10 The rate of placing of concrete in the pile shaft shall not be less than 6 m
(length of pile) per hour.
02.05.11 Boring of any pile shall not be carried out within a clear distance of three times
of the pile diameter from the adjacent pile which has been freshly concreted
within past 24 hours.
02.05.12 The contractor shall have to take all necessary actions to prevent side collapse
(if any) of pile bore at his own cost.
02.05.13 The Contractor shall be responsible for the prompt removal from the site of all
spoil due to the boring to places as indicated by TANGEDCO. The cost of
such disposal shall be deemed to have been included in the rate of piling.
All the piles shall be socketed in specified rock stratum, with stipulated socket
length, as mentioned in Geotechnical Specification of the package.
It is to be ensured by the contractor that, the piles are not terminated in boulder
deposit, if any.
For each pile, representative rock samples shall be collected from the top &
bottom level of rock socket portion. Either rock lump samples collected by
Bailer or rock core samples collected by rotary core drilling technique, shall be
used for identification of specified rock stratum for socketing. All such
samples shall be preserved for future reference.
The contractor shall engage a qualified & experienced geologist at site, for
identification of specified rock stratum for pile socketing.
For this package, One number Initial Pile Load Test shall be conducted, for
each mode of loading (Compressive, Pull-out, Lateral).
Separate Trial piles shall be used for testing in each mode of loading
(Compressive, Pull-out, Lateral).
Initial Test piles shall be constructed using the same equipment & technique &
by same piling agency, as for working piles.
While executing the pile bore for Test Piles, a continuous record of borelog
shall be maintained and Standard Penetration Test as per IS:2131at an depth
interval of 1.5 m including one compulsory test at termination level, shall be
conducted at no extra cost.
For Routine Load Test in Lateral mode of loading, 2(two) numbersof working
piles shall be tested.
Separate working piles shall be used for testing in each mode of loading.
Exact location of the working pile to be tested for Routine Load Test, shall be
indicated by TANGEDCO at site.
Test load in such tests may be limited to 1.5 times of the corresponding safe
design load.
02.07.03 For all types (Initial / Routine and Compressive / Pull-out / Lateral) of load
tests, testing arrangement, test procedure shall follow relevant criteria set out
in IS:2911(part 4) along with the following stipulations:
ii) Load test shall be carried out after 28 days from the date of casting.
iii) Test load shall be applied at cut-off level. If the test level is below the ground
water table, suitable arrangement for dewatering shall be made by the
contractor without any extra cost so as to conduct the test at dry condition.
v) Test load shall be applied to pile in a static manner. Stage loading shall be
applied in equal increments of 20% of estimated safe design load. Unloading
may be done in higher decrements with at least 5 stages. For Cyclic Load test,
each stage of loading shall correspond to unloading upto zero load. At each
stage of loading & unloading, deflection of pile top shall be recorded accurate
to 0.02 mm at an interval of 1, 2, 4, 8, 15, 30, 60 & 120 minutes upto a time
when the deflection rate reduces to 0.1mm in 30 minutes or 0.2 mm in one
hour or till two hours whichever occurs earlier.
vi) Increments of loads shall be continued upto Maximum Test Load (2.5 times of
safe design load for Initial Test & 1.5 times of safe design load for Routine
vii) Where failure does not occur, the final test load shall be maintained for 24
hours and deflection records shall be taken at every 6 hours interval, including
initial 2 hours detailed records, as mentioned earlier.
viii) The contractor shall ensure that all the instrument / apparatus used by him
shall be properly calibrated. The calibration certificates (not older than one
year) of all the dial gauges & pressure gauges proposed to be used for load test
shall be available at site. If TANGEDCO desires to check any calibration, the
contractor has to arrange the same in an approved laboratory at his own cost.
ix) The Contractor shall maintain & submit TANGEDCO immediately after
completion of any load test, the following records / reports:
b. Tabular & Graphical representation of the Time vs. Settlement for each
load.
c. Graphical analysis of initial cyclic load test results (if any) to separate
skin friction & end - bearing. as per Annexure A, IS 2911 (part 4).
02.07.04 In case of failure of piles, in load test, to achieve the specified safe design
load,the contractor shall install extra piles at his own cost as per design
requirement & as instructed by TANGEDCO.
The piles shall be accepted as satisfactory only when the work has been
executed in accordance with this specification, IS Codes, and the Standards
stated herein and instructions given by TANGEDCO at site from time to
time:
a) The total volume of concrete shall not be less than actual shaft volume. The
calculated volume for this purpose shall be the cross sectional area inside the
bore multiplied by the length of the shaft. The concrete shall conform to the
specified strength as indicated by the cube test results.
c) Safe Load carrying capacity of pile as obtained from Load test shall not be less
than corresponding Safe Design Load as mentioned.
When any pile is found defective, one or more pile shall be installed as a
replacement of defective pile as necessary without any extra cost to
TANGEDCO. Defective piles shall be left in place or pulled out as directed by
TANGEDCO. Contractor shall not be paid any additional amount on this
account. No payment shall be made for test piles found defective /
unsatisfactory.
02.09 Record
The contractor shall maintain a record for each pile indicating the following
data and shall be signed jointly with TANGEDCO.
a) The date and time of commencement and completion of each stage of piling
operation.
c) The location and type of pile, Pile number, with a reference to approved
drawings.
e) Bored depth, concreted depth, empty boring and nature of stratum at founding
Level.
f) The volume of concrete poured, quantity of cement, w/c ratio used and slump
of poured concrete.
j) During chiseling through hard stratum, if encountered, exact record for depth
of penetration against time & number of blows for each 10 cm of chiseling
shall be maintained. Weight & average height of fall of chisel shall also be
recorded.
The Control Cum MCC Room Building, Compressor House Buildings will house the
following functional spaces i.e. Cable Cellar, Chiller Plant, A/C & non A/C Switchgear
Room, Clean Agent Room, Control/Equipment Room, Control/ Operator Desk, Cabins,
Offices, AHU Room, PPVS Room, Store & Utility Room, Analyzer room, Operator
room, Pump house etc as per the Technological requirements including other common
spaces. There will be toilets for male and female (as per NBC norms). Sufficient
Staircase (as per NBC norms) will be provided at appropriate location. Waiting,
adequate Circulation area, UPS room, Electrical room, AHU room, A/C plant room etc
will be provided suitably. False ceiling shall also be provided in all the A/C areas.
The design concept for above building will meet the functional, technical and other
requirements for efficient operation, ensuring sufficient lighting and ventilation for
conducive working environment for employees, satisfying the overall modern befitting
building aesthetic requirements. The referenced Publications given below will be
followed for the designing purpose: BIS, NBC, BPE & British codes.
01.03.01 Buildings will accommodate spaces to meet the functional requirements as well as
security/safety, maintenance, statutory (stairs/fire exits etc.), utilities & services
(toilets/AC/Electrics/LAN/health etc.)/environmental requirements and incorporated in
design & detail engineering drawings/documents.
01.3.02 Space requirements as indicated in this part of TS is not exhaustive and subjected to
finalization by consultant/Employer during detail engineering stage with modifications
required to meet the building requirements as per technological need.
01.03.03 Sizes of the functional spaces both indicated and not indicated, will be verified against
technological requirements, number of users / furniture layout etc, finalized and
provided.
01.03.04 Functional office spaces in the building will be designed as column free spaces
wherever possible, with provisions for full height cabins, low height cubicles, Open
office area etc. to ensure unobstructed day lighting for the work spaces.
The area of windows will be a minimum 15% of the floor area to ensure adequate
natural lighting and ventilation.
01.05 Services
There should be adequate space for all services The main stair case should be
prominent one, visible and easily accessible from entrance. The pipe lines from toilets
and rain water pipes will preferably be enclosed in ducts, but easily accessible for
maintenance purpose and will not spoil the aesthetics of the building.
01.06 Parking
Separate and sufficient Parking will be provided for four wheeler & two wheeler
located near the building and tubular steel structure with coloured metal sheeting &
interlocking pavers blocks (60mm thick) will be provided for the covered shed.
Finished Floor level (FFL- plinth level) will be 300mm (minimum) above the Road
Level.
01.09 Landscaping
Landscaping will include hard-scape, soft-scape including turfing & gardening with
fencing without boundary wall around the building & in vacant spaces. Water tapping
points at convenient locations and micro terracing (if required) by the contractor within
their battery limit. Adequate Trees/plants those can grow in the local soil & climatic
conditions will be planted in proper sequence to provide greenery & Seasonal plants
for gardening will be provided at strategic locations.
01.10 Stairs
Stairs, having each flight width of minimum 1500mm, will not have normally more
than 15 risers in one flight, with maximum riser of 165mm and a minimum tread width
of 250mm. Proper edge protection has to be ensured. All roofs will be accessed through
the staircases.
01.11 Handrails
Stainless steel ( Grade 304) 1000 mm height of knock down fixing system railing made
of 38 mm dia stainless steel Handrail (Wall Thickness 1.5mm), 40mm x 40mm SS
Square Baluster (Wall Thickness 1.5mm), @ 900mm (maximum) c/c with complete
fixtures, 16mm dia x 3 Nos. SS Horizontal Member shall be provided in staircase,
steps.
All accessible areas will be provided with a minimum clear headroom as follows,
unless otherwise specified:
All walls will be non load bearing infill panel walls. External walls of all buildings will
be at least one brick thick. All internal walls will be at least half brick thick excepting
staircase, toilets, AHU etc. with one brick wall.
The thickness of the parapet wall will be one brick thick or 125 thick R.C.C. wall and
height will be 1000 mm minimum for accessible roof & 500 mm for non accessible
roof.
Roof drainage system will be provided for quick and efficient draining of rainwater
from roof to avoid seepage and damage to roof. The roof gradient for the roof will not
be less than 1 in 100. Roof drains will conduct water to storm drains through UPVC
down take pipes. Rainwater pipes (Type -A, conforming to IS :13592) with all
necessary fittings i.e. pipe clips, shoe, inlet mouth, bend of required degree, coupler,
TEE with or without door, etc to be provided as per manufacturers specifications.
01.15 Drainage
Garland drain will be provided after providing plinth protection all around the building
to receive drainage water from roof & floor and lead them to the plant storm water
drainage.
All the applicable statutory rules pertaining to Indian Factories act, factory rules of state
government, Fire safety rules of LPA, Water act of Pollution Control Boards,
Explosives act etc. and stipulations of other relevant statutory authorities will be taken
into consideration at the time of design.
Provisions of safety health and welfare according to factories act will be complied in
design stage. These will include provision of fire escape, locker room for workmen,
toilets rest room etc.
01.17.01 Entrance to be provided at proper location with canopy/ projection as per design.
01.17.02 600 mm projection to be provided over each window & ventilator and 1000mm
projection over each external door
01.17.03 Drop Slab (550 clearance) should be considered for toilet block to be filled with jhama
brick bat/ cinder or as directed by Engineer In charge.
01.17.04 Skirting will be of same finish as that of floors. Panel dividers will be provided in
cement concrete/non metallic Heavy Duty flooring
01.17.05 All Air-Conditioned areas will have 12.5 mm thk. MR Gypsum board or approved
equivalent false ceiling.
01.17.06 Painting on Internal masonary walls will be done over White cement putty minimum
1mm thick & primer as per manufacturer specification.
01.17.07 All steel frames, Shutters, Grills etc will be painted with two or more coats of approved
quality Synthetic Enamel Paint of Approved shade over a coat of Approved quality red
oxide /Zinc Chromate Primer.
01.17.08 All paints shall be low VOC paint in nature as per manufacturers specifications. Acrylic
emulsion paints (Internal & external) to be applied minimum two coats on all surfaces,
if required additional coats to be applied to achieve even shade and colour.
01.17.09 False flooring shall be as per item No. 11.54 of DSR and finished with 2mm thick
antistatic PVC tiles will be provided. (As per technical requirement)
01.17.10 General technical specifications (GTS) also to be referred along with this technical
specifications, however if any discrepancy is found, technical specifications shall
prevail over GTS.
01.17.11 If specification for any item is not covered in this TS or GTS then CPWD specification
to be referred for respective item.
01.17.12 1st quality ceramic glazed tiles conforming to IS: 15622 to be used in toilets, janitor of
approved make, shade & complete in all respect
01.17.13 Double charged vitrified tile to be used conforming to IS: 15622 with water absorption
less than 0.08% and of size 600x600 mm
01.17.14. Internal wall plaster with 12 mm thick cement plaster of mix: 1:6 (1 cement : 6 fine
sand), External wall plaster with 20 mm thick cement plaster of mix: 1:6 (1 cement : 6
fine sand ), ceiling plaster with 6 mm thick cement plaster of mix: 1:3 (1 cement : 3 fine
sand)
01.17.15 Chicken wire mesh to be provided in the plaster on the location of RCC & brick joints.
01.18 Finishes.
Exterior grade Premium Acrylic Smooth exterior paint with Silicone additives over
plaster & Acrylic modified resin based texture (approx. 20% of the external area) of
approved Pattern having anti algae and UV resistance properties to be provided over
plastered wall.
All the floors of electrical building/control rooms, cable cellar/basement will have
minimum two entries/ exits with lobby and two air tight doors. Rolling shutters (if
required) shall be provided in all electrical rooms/ventilation rooms/ AHU rooms in
addition to doors.
Glass for doors, partition and windows to be taken as 6mm thick toughened glass/
frosted glass for toilet.
Doors & Windows to be provided as per attached schedule and will meet following
specifications:
01.19.01 Doors
01.19.01.01 Pressed steel door frame (Upto 1000mm opening Profile type B, above 1000mm
opening Profile type C as per IS-4351 with 35 mm thick flush door shutter as per IS:
2202 (Part-I) (Teak wood Veneer finished on both side) with 1.5mm thick laminates
pasted on both sides (factory pasted) of approved shade and finish. (Vision panel should
be provided in the shutter).
01.19.01.02 PVC door frame with 30mm thick rigid foam PVC paneled door shutter with paneling
of 5mm thick PVC sheet should be considered in all toilets, janitor room. (DSR -9.119
for Frame), DSR -9.120.2 (Shutter) – Refer DSR -2007.
01.19.01.03 Fire rated Door: Minimum 2 hrs rated fire resistant doors to be provided at all fire exit
points. The door frame shall be as per item No. 9.161 of DSR and door shutter shall be
as per item No. 9.162 of DSR with viewing glass as per item No. 9.164 of DSR. The
door assembly shall be fitted with approved S.S. hardware, panic bar/latch as per item
No. 9.139 of DSR. The door assembly shall be of approved make.
01.19.01.04 Rolling Shutter as required to be provided as per IS code & Steel door with steel frame
with anti corrosive paint as required.
01.19.01.05 Doors and windows of rooms, which are air conditioned, will be air tight and dust –
proof.
01.19.02 Windows
01.19.02.01 All windows shall be sliding / casement/ louvered glazed anodized (AC 25) Aluminium
windows as per standard aluminium section provided including 6mm thick toughened
glass/ frosted glass for toilet, approved quality hardware and all the gaps between frame
and wall to be filled with approved silicone sealant and backer rod (if required). Shop
drawings to be submitted for approval.
01.19.02.02 All windows to be provided with ornamental anodized aluminium grill (anodized
transparent or dyed to required shade according to IS: 1868 with minimum anodic
coating of grade AC 15) of approved design/pattern, with approved standard section
and fixed to the existing window frame with C.P. brass/ stainless steel screws @
200mm centre to centre, including cutting the grill to proper opening size for fixing and
operation of handles and fixing approved anodized aluminium standard section around
the opening, all complete as per requirement and direction of Engineer-in-charge.
01.19.02.03 Doors and windows of rooms, which are air conditioned, shall be air tight and dust
proof.
A. Normal Door
1. Door Vertical Plain 9239 85x44.5x2 1.365
2. Door Vertical 9241 -do- 1.412
3. Door Bottom (Shutter 9208 101.1x44.5x3. 2.379
Width<=1 Mt) 1
4. Door Bottom (Shutter Width >1 9212 180x44.5x3.1 3.438
Mt) 8
5. Door Top 9208 101.1x44.5x3. 2.379
1
6. Lock Rail 9232 150x44.45x3. 3.290
2
7. Glazing Clip 4660 19.7x17.8x1.3 0.167
II WINDOWS
A. Casement– 40mm Series
III. PARTITIONS
01.20.01 Toilet alongwith Drinking water, Janitor & Over head water tank to be provided as per
NBC guidelines.
01.20.02 Each toilet block shall have the following minimum facilities. Unless specified all the
fittings shall be of chromium plated brass.
01.20.03 CPVC pipe of SDR-11 class, conforming to IS:15778 to be used in concealed internal
plumbing network with all required accessories and fixing materials, all complete.
Fixing Chlorinated Polyvinyl Chloride (CPVC) pipes, having thermal stability for hot
& cold water supply, including all CPVC plain & brass threaded fittings, i/c fixing the
pipe with clamps at 1.00 m spacing. This Includes jointing of pipes & fittings with one
step CPVC solvent cement including testing of joints complete as per direction of
Engineer in Charge. Scope also covers connection from water storage tank to concern
toilet in all buildings.
01.20.04 Hubless centrifugally Cast (spun) Iron epoxy coated inside and outside pipes shall be
used as Soil and waste pipe jointed using SS 304 grade shielded coupling with EPDM
gasket along with necessary bends, offsets, traps, fixing materials all complete.
01.20.05 CP brass pressmatic tap with connection pipe and spreader shall be used for Urinals.
01.20.06 Polyethylene water storage tank ISI : 12701 marked, with cover and suitable locking
arrangement and making necessary holes for inlet, outlet and overflow pipes, with all
fittings including valves and the base support for tank (above 1000 mm from roof
level). Above tank shall be provided in all buildings comprising toilet of required
capacity as per NBC norms.
01.20.07 The toilet area shall have finished floor level at 15 mm below the finished floor level of
surrounding area.
01.20.08 Kitchen sink with drain board (size: 510x1040 mm bowl depth 200mm) and without
drain board (610x510 mm bowl depth 200mm) to be provided in all Kitchen/ Pantry
with all fittings, pipes, complete in all respect: Stainless Steel AISi 304 (18/8) kitchen
sink as per IS: 13983. In kitchen & Pantry sink will be provided with drain board & in
Drinking water area, Scrub-up etc areas sink will be without drain board.
01.20.09 Granite stone slab with table rubbed, edges rounded and polished, of size 75x50 cm
deep and 1.8 cm thick of approved shade, to be fixed in urinal partitions by cutting a
chase of appropriate width with chase cutter and embedding the stone in the chase with
epoxy grout or with cement concrete 1:2:4 (1 cement: 2 coarse sand: 4 graded stone
aggregate 6 mm nominal size) as per direction of Engineer-in-charge and finished
smooth.
01.20.10 Fixing 18 mm thick gang saw cut, mirror polished, pre-moulded and pre-polished,
machine cut for kitchen platforms, office counters, window sills, facias, wash basin
counters, drops of counters and similar locations of required size, approved shade,
colour and texture laid over 20 mm thick base cement mortar 1:4 (1 cement: 4 coarse
sand), joints treated with white cement, mixed with matching pigment, epoxy touch
ups, including rubbing, curing, moulding and polishing to edges to give high gloss
finish etc. complete at all levels. Also making opening for kitchen sink, wash basins etc
including necessary holes for pillar taps etc. including moulding, rubbing and polishing
of cut edges etc. complete.
01.20.11 600x450 mm beveled edge mirror of superior glass (of approved quality) above all
wash basins complete with 6 mm thick hard board ground fixed to wooden cleats with
C.P. brass screws and washers, all complete.
01.20.12 600x120x5mm glass shelf with edges round off, supported on anodised aluminium
angle frame with C.P. brass brackets and guard rail complete fixed with 40 mm long
screws, rawl plugs etc. below all mirrors, all complete.
01.20.13 S.S. toilet paper holder with all the W.C.s, complete in all respect
01.20.14 C.P. brass bib cock of approved quality conforming to IS:8931 to be provided at all
required places.
01.20.15 White Vitreous china Orissa pattern W.C. pan of size 580x440mm with integral type
foot rests with 100mm sand cast Iron P or S trap, 6/3 litre dual flush low level white
P.V.C. flushing cistern, including flush pipe, with manually controlled device (handle
lever) conforming to IS : 7231, connection pipe with brass union, C P brass Quarter
turn angular stop cock, with all fittings and fixtures complete including cutting and
making good the walls and floors, all complete as per instruction of the Engineer in-
charge
01.20.16 White glazed vitreous China pedestal type water closet (EWC) of Hindware
(ECOCat.No.20044) size 38.5 x34.5x50.3 cm,/ nearest size of Parryware or similar
approved equivalent, double trap siphonic pattern, inte-gral with "P" or "S" trap, with or
without vent horn , 3/6 litre flushing low level PVC cistern (Sleek Dual), with all
accessories , PVC flush pipe 32/40 mm dia and 15 mm dia unplasticised PVC inlet
water connection pipe of superior quality with brass union and C P brass Quarter turn
angular stop cock with wall flange of Jaquar (Florentine-Cat. No-FLR- 5053N) / similar
Vol. – VB ARCHITECTURAL WORKS Page 13 of 20
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TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION - I (4X210MW)
approved equivalent, white solid plastic seat cover and lid of superior and approved
quality, CP brass bar hinges, screws, bolts, rubber and stainless steel washers, rubber
buffers, fixing EWC to floor with all bye-works cutting and making good the walls and
floors, all complete as per instruction of the Engineer In-charge
01.20.17 White glazed vitreous China flat back, front lipped standing urinal size 59 x 39 x 37.5
cm of Hindware (Cat. No.60002) ,/ nearest size of Parryware or similar approved
equivalent, with concealed CI wall hangers , 32 mm dia PVC waste pipe & C.P dome
shaped perforated waste with union of superior quality with CP brass coupling upto
floor, 95x69x100 size spreader, 80x42x30 size urinal cock with all bye-works cutting
and making good the walls and floors, all complete as per instruction of the Engineer
In-charge.
01.20.18 Under counter wash basins will be provided for toilets at Office floor, in other locations
White Vitreous China flat back Wash basin of size 550x400 mm to be provided. All
wash basins to be provided with connection pipe with brass union, waste pipe, waste
coupling, quarter turn brass Pillar Taps, Brackets, cutting and making good the walls,
all complete.
01.20.19 All W.C., Wash basin, Sink to be provided with CP brass quarter turn angular stop cock
with adjustable wall flange of Jaquar (Cont.-cat. No-FLR-5053N) or approved
equivalent make with all bye-works cutting and making good the walls, complete in all
respect.
01.20.20 S.S. liquid soap container to be provided near all Wash basins with brackets etc with all
bye-works cutting and making good the walls, complete in all respect.
01.20.21 600 mm long single towel rail with brackets of Jaquar (Cont.-cat. No-1111N) / similar
approved equivalent fixed on wooden plugs with CP brass screws to be provided with
all bye-works cutting and making good the walls, complete in all respect.
01.20.22 C P Brass Health faucet with flexible connection pipe for W.C. to be provided in all
toilets all complete.
01.20.23 C.P. Brass long nose bib cock/ long body bib cock of approved quality conforming to
IS standards to be provided for Drinking water area/ sink area (if required), complete in
all respect including all bye-works cutting and making good the walls.
01.21 Drawings
In case, the items are not available in the market or in case of a change in trade name,
equivalent makes/ re-designated manufacturer shall be used with prior approval of
MECON. In case of items are not covered in the list, the material shall procured after
approval of MECON as per the standard material available in the market and having
BIS certification mark.
01.01 General
This specification for Steel structural works furnished herein are intended as guidelines
for execution of the works satisfying the Owner’s requirements as also complying with
all technical norms in totality This specification shall apply to Design, Supply,
fabrication, erection of steel structures including paintings and cladding of structural
buildings in general on turnkey basis and dismantling for installation of Semi Dry Flue
Gas Desulphurization System/ Equipment in Mettur Thermal Power Station (MTPS- I:
4 x 210 MW)
01.01.01 Units
Structural steelwork under the scope of this specification shall consist of the units
broadly described under the clause no. 1.4.
The following gives only general description of steel structural work. The structural
work shall not be limited to these but shall be guided by Technological / Technical
requirements and aspects for the total scope of work for FGD system.
General description of structural work for structural buildings, structural shed, structural
platform, walkway, structural support for pipe rack/ trestle, stairs, etc. involved in
installation of Semi Dry Flue Gas Desulphurization System/ Equipment in Mettur
Thermal Power Station (MTPS - 4 x 210 MW). The structural work shall not be limited
to these but shall be guided by technical/technological aspects for the total scope of
work.
The above descriptions of steel structural works are indicative only and not limited only
to as mentioned, if any other units are deemed necessary for completion of the Project
those are to be supplied by the Bidder. Successful Bidder shall also ensure the adequacy
of the building parameters to suit equipment layout and technological requirement. If
the Bidder wants any deviation, he shall indicate the same and also the building
parameters unit wise in his offer.
01.01.05 The work to be performed under this specification consists of design, engineering ,
supply, fabrication, erection and cladding, as well as providing all labour, materials,
consumables, equipment, temporary works, temporary labour and staff colony,
constructional plant, fuel supply, transportation and all incidental items not shown or
specified but reasonably implied or necessary for the completion and proper functioning
of all the above units, all in strict accordance with the specifications, including revisions
and amendments thereto as may be required during the execution of the work.
01.01.06 Supply of all materials including structural steel, roof cladding & side-cladding sheets,
fasteners, paints, consumables like gas, electrodes etc. and all other materials as deemed
necessary for proper completion of the work, are included in the scope of the Bidder.
01.01.07 The work shall be carried out according to the design/drawings to be developed by the
Bidder and approved by the Owner/Consultant. For all buildings and structures,
necessary layout and details are to be developed by the Bidder keeping in view the
statutory & functional requirements of the plant and facilities and providing enough
space and access for operation, use and maintenance. Certain minimum requirements
are indicated in this specification for guidance purpose only. However, the Bidder’s
offer shall cover the complete requirements as per the best prevailing practices and to
the complete satisfaction of the Owner .
01.02.01 The scope of work shall cover, but shall not be exclusively limited to, the following:
This specification shall apply to steel work in buildings and general structural steel work.
For technological structures, additional stipulations shall be considered as per technical
requirements.
The Steel Structures shall generally be designed following IS: 800-2007 (Limit State
Design method )
Dead loads consist of the weights of the complete structure with finishes, fixtures,
partitions, wall panels and all equipment of semi-permanent nature including storage
structures (tanks, silo etc.), partitions, roofing, piping, cable trays, bus ducts etc. The
content of storage structures etc. shall be measured at full capacity for this purpose.
The piping loads, cable tray loads and the contents of the storage structures shall be
listed separately so that they can be excluded from dead load when dead loads are acting
as stabilizing load for uplift.
The following unit weight of material shall be considered for computation of loads.
Loads given in IS: 875 (part-I) shall be made use of for material not listed below.
Table 1.1
When thermal loads (such as produced by temperature changes in piping, equipment and
structures) results in friction between equipment and supports (exchangers) or piping and
supports, the friction force will be taken as the operating load on the support multiplied
by the applicable friction coefficient given below:
Loads considered in design shall allow fully for all aspects of:
b) Superimposed loads for roofs and floors plus any temporary machinery not allowed
within the general superimposed loads.
c) Crane loading.
g) Dynamic loads from screens and other such reciprocating/ vibrating machinery.
j) Seismic loads Zone-II as per IS:1893(latest). Zone factor shall be 0.1 & Importance
factor shall be considered as 1.75
o) Rain fall: Annual rainfall intensity shall be considered as 100mm per hour.
p) Spillage Load
gallery walk way : 1KN/sqm.
Seal plate : 1KN/sqm.
Belt tension for twin conveyor : One belt at start condition and one in running
condition
Impact factor for drive machine= 1.5
i) Besides technological loads, all platforms, walkways, stairs etc. shall be designed for the
following live loads:
i) Ladder : 0.9 KN
at middle of rung
k) All structures supporting vibrating equipment shall be overloaded by 25% of static load,
unless specified otherwise.
l) For design of monorails, hoists etc, an impact factor of 1.25 for electrically operated
cranes and 1.1 for hand operated cranes, shall be considered. Weight of pulley block and
other accessories shall be considered
ii) For all other loads, not specified above, the following codes shall be followed.
a) All live loads shall be considered in accordance with IS: 875(Part-2) -1987.
b) Wind loads shall be in accordance with IS: 875(Part-3) -2015 and any other
consideration specific to the site. For wind load calculation the following data may
be considered
- Terrain ht and Structure size factor (K2) shall be calculated with Category 2.
II. IS: 875(Part-2) -1987 for conditions not covered in IS: 800 unless more severe loads
have to be considered for technological/operational conditions.
e) Crane stopper shall be designed in accordance with clause 6.1.4 of IS: 875 (Part-5)
-1987.
f) For design of bins and loading hopper IS: 9178 (Part I to III) shall be followed.
f) In absence of any suitable provision for design loads, any other recognized code of
practice may be followed subject to prior approval of the Purchaser.
Vol. – VC STRUCTURAL WORKS Page 6 of 23
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CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION-I (4X210MW)
g) Equipment loads shall be considered over and above the imposed loads. Equipment
loads (apart from dead weight) shall be considered as given by equipment supplier.
Various design loads considered shall be combined in accordance with clause 8.0 of IS:
875(Part-5) -1987 and also to give the most severe loading condition for design of
structures.
Deflections are to be checked for the most adverse but realistic combination of service
loads and their arrangement by elastic analysis using a load factor 1.0
Vertical Deflection
Horizontal Deflection
prop )
iv) Sway of building frame structure at eaves level : H/400
v) End portal of Conveyor gallery girders : Height/325
vi) Sway of 2-legged trestles for supporting : Height/1000
Conveyor gallery girders in transverse
direction
vii) Sway of 4-legged trestles for supporting : Height/1000
Conveyor gallery girders in transverse
direction
viii) Sway of 4-legged trestles for supporting : Height/500
Conveyor gallery girders in longitudinal
direction
ix) Transverse deflection of Junction Houses : Height/500
x) Differential sway deflection between two : Height/1000
floors in Junction Houses where one conveyor
on upper floor feeding another conveyor on
lower floor
c) All other limits of deflection, not specified above, in various elements of structures shall
be in accordance with IS: 800-2007.
01.03.01.06 Camber
a) Longitudinal and transverse expansion joints shall be provided in buildings and structures
in accordance with IS: 800-2007.
b) For open gantry structures, pipe line stockades, cable galleries, open conv. galleries
expansion block width shall be limited to 120m.
c) Expansion joints shall be formed by providing double rows of columns, with overhanging
gantry girders, secondary roof and wall framing being detailed to allow the maximum
calculated movement for the specified temperature variation.
01.03.02.02 The effective ratio of utility of all sections & welds shall be limited to 0.85.
01.03.02.03 The minimum thickness of structural steel elements shall be in accordance with IS: 800.
Minimum size of beam members, channel members and angle members shall be ISMB
200, ISMC 75 & ISA 50X50X6 respectively. Channels used as floor beams shall not be
smaller than ISMC 150. For column bracings single angles shall not be used. All Plates
of a particular thickness, used in any specific package, shall be of same grade.
01.03.02.04 The diameter of structural bolts shall not be less than 20 mm except for those securing
roof and wall sheets, windows, doors and stitching of thin coverings. For bolted joints, at
least two bolts per joint shall be provided. Minimum diameter of sag rod shall be 16mm.
01.03.02.05 All butt welds shall be full penetration butt welds.
01.03.02.06 The size of fillet welds shall not be less than 6 mm or thickness of the part welded.
01.03.02.07 Structures shall be designed such that they are economical and safe and meet the
functional and service requirement of the technological process for which they are
designed. The architectural planning of the building shall be based on technological
requirements.
01.03.02.08 The structures shall be designed conforming to the relevant safety regulations, Factory
Acts, Electricity Rules and stipulations of statutory bodies as applicable to the project.
01.03.02.09 Natural ventilation shall be provided ensuring that it does not permit rain water entry
into the building. Scope of natural lighting shall be used to the maximum possible
extent. For this purpose, 15% of side sheeting area and 10% of roof sheeting area, unless
otherwise specified, shall be provided with translucent sheets. Protective grating shall be
provided below such sheets to prevent accidents due to damaged sheets.
01.03.02.10 Expanded metal sheet of net size 200 mm X 75 mm and thickness 5 mm as per IS: 412 –
1975 OR standard wire gauge (SWG 10) or 3.251 mm wire mesh of net size 75 mm X
150 mm, shall be provided below the translucent sheets. The mesh shall be firmly fixed
with a frame made of flats of size 50 mm X 6 mm and connected to roof purlins for
safety against possible breakage of sheets due to continuous exposure to sun & heat and
due to live load. The mesh shall not touch the sheet. The mesh thus fixed shall be able to
cater for a load of 75 kg/sq.m or a point load of 75 kg in the middle.
01.03.02.11 Mild steel gutters and down-pipes with gutter outlets having grating cover shall be
provided to carry rain water from roofs of buildings to the drainage system at ground
level. All gutters shall be designed as walkable with 600 mm sole width.
01.03.02.12 Adequate facilities in the form of monorails, hoists, platforms etc. shall be provided to
facilitate repair and maintenance of overhead cranes, equipment, etc. Access to these
platforms shall be provided by stairs / ladders from the nearest accessible floor or
platform.
01.03.02.13 Access to all floors, gangways and landings shall be by staircases. Access to platforms
and landing of secondary importance or where such access is used only rarely, shall be
by vertical ladders with safety hoops. Roofs with access shall be provided with safety
handrails along the periphery of the roof.
01.03.02.14 Edges of floors, gangways, stairs and landings shall be provided with safety hand
railings. All hand railings shall be of tubular hand railings with vertical post, top rail and
mid rail made up with tubes.
01.03.02.15 At gable ends of buildings, platforms shall be provided connecting the walkways at
crane gantry level.
01.03.02.16 Floors, gangways and landings shall be covered as follows:
a) Gangways and landings shall have chequered plate with a minimum thickness of 6mm o/p
suitably stiffened to meet design load requirements.
b) Floors and operating platforms other than the above shall have chequered plate flooring or
electro-forged gratings, resting on steel structural framework, to suit the technological
requirements. Floor bracings shall be provided in all working floors to take care of the
horizontal loads, due to equipment / due to seismic consideration / owing to nominal skew
forces.
01.03.02.17 All buildings and their foundations shall be designed so that it shall be possible to extend
them in the longitudinal direction at a later date without further strengthening of gable
structures. Provision for transverse extension, if any, shall also be made at the initial
stage.
01.03.02.18 Sheeting on sides and gables shall generally terminate 2.5 m above ground floor level
unless required to be otherwise. Sides below this level shall be generally screened by
brick walls allowing sufficient air inlet to achieve natural ventilation, unless otherwise
required from technological / ventilation requirements.
01.03.02.19 Connection by permanent bolts to structural elements subject to vibration shall be
provided with lock nuts.
01.03.02.20 Monorails shall be designed for local bending both in transverse and longitudinal
direction. Any Mono Rail cantilevered for more than 1500 mm shall have vertical
support.
01.03.02.21 For Analysis of steel structural frame work STAAD PRO soft ware shall be used. And
for design of members EXCEL shall be used. Soft copy of the executable STAAD file
shall be submitted to purchaser / consultant along with the hard copy of the drawing for
its approval. Backup calculations for input loads as well as design of individual elements
carried out separately, shall also be submitted. The design sheets (e.g. editable EXCEL
files indicating active formulas) shall be submitted for all members. No separate design
criteria shall be proposed except for any clarifications / discrepancies.
01.03.02.22 Chequered plates, Purlins, Side runners, sheeting etc shall not be considered as structural
members for transferring horizontal loads. Except where purlins form part of bracing
system and designed for axial loads also.
01.03.02.23 Design drawings submitted by the vendor shall carry the signatures of the designer and
the approval authority of the vendor. Each drawing shall have a unique drawing number
& a unique description. Drawing shall have enough free space for client’s comments and
stamp of approval.
01.03.02.24 Vendor shall submit readable structural design drawings (including Bill of Material) to
purchaser / consultant for approval, along with the approved technological drawings. All
other supporting documents like the detailed load calculation, design sheets shall be
submitted for reference along with design drawings.
01.03.02.25 If any revised drawing is entirely different from its previous revision, this should be
given a fresh drawing number scrapping the earlier revision.
01.03.02.26 Even if the drawings are approved / Commented by the Purchaser / Consultant, the
Contractor shall not be relieved of the responsibilities for the accuracy of the detailed
dimensions shown in the drawings and the safety of all structural connections.
01.03.02.27 Design drawings shall contain design forces, major load data of equipment considered
and member design forces like moment, shear, axial force values, Section-wise Bill of
Quantity etc .Necessary number of prints of drawings and documents; as per contract
shall be submitted for approval.
01.03.02.28 After approval of the design drawings a scanned soft copy bearing the stamp of approval
shall be submitted to the Purchaser / Consultant for reference.
01.03.02.29 The slopes of bracings, lacings for columns, diagonal members of trusses, bridges,
girders etc shall be kept preferably in the range of 35 to 50 degrees.
01.03.02.30 Structural steel sections & plates shall be so selected that they are readily available in the
market. A list of such sections & plates shall be submitted for Purchaser’s approval
before commencing design works.
01.03.02.31 Purlins and side runners shall be considered as part of cladding unit and shall be
subjected to local wind coefficients as specified in IS 875(Part-3)-2015.
01.03.02.32 Resonance in structures: Structures supporting vibratory/reciprocating equipments shall
be designed so as to obviate occurrence of resonance. The ratio of applied frequency to
natural frequency shall not lie within the range 0.7 to 1.5.
01.03.02.33 All 2-legged trestles shall be completely braced in vertical plane. All 4-legged trestles
shall be completely braced in all four vertical planes. In addition, specified horizontal
planes shall be completely braced to provide stiffness against torsional sway.
01.03.02.34 All bunkers shall have liner plates as specified by technological sections according to
their requirements.
01.03.02.35 The design drawings shall be submitted in complete for a unit along with design
calculations both in hard copy and soft copy.
01.03.02.36 Structural schematic general arrangement with plans at various levels, elevations along
each row and axes, sections, considered loads and load diagrams with location etc. and
Structural design drawings with BOQ and Table of members containing design forces
along with design calculations shall be submitted for Purchaser’s/Consultant’s approval.
However the approval shall be limited to checking of overall dimensions, general
stability of system, effective load transfer and deflection limits etc. The approval shall
not relieve the contractor of his responsibility of correctness in design, adequacy of
connections, accuracy etc.
01.03.02.37 Submission of Stability certificate for all the steel structures is under the scope of the
contractor.
01.03.02.38 Main structural elements shall be welded continuously. Intermittent welding shall be
used only on secondary members who are not exposed to weather or other corrosive
influence.
01.03.02.39 Field connection and splices shall be made in one of the following ways:
01.03.03.01 Columns
a) Shear force at the column base shall be resisted either by shear keys shop welded to the
underside of column base plates or by welding base plate to inserts provided in
foundation.
b) The level of underside of column base shall be so chosen such that the base plate/ anchor
table lies above the finished ground level, by at least 500mm.
c) Minimum thickness of base plate for columns at ground level shall be 20 mm (at other
levels 16 mm) and minimum thickness of washer plate at any level shall be 0.5 times of
Base Plate thickness.
Vol. – VC STRUCTURAL WORKS Page 12 of 23
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TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION-I (4X210MW)
d) All Built-up columns shall be provided with nominal stiffeners to maintain orthogonal &
torsional rigidity, at a spacing not exceeding 1500 mm centre to centre.
e) All laced columns having individual depth more than 600 mm, shall have diaphragm
plates at alternate lacing points.
i) Screen supporting shall be preferably concrete floor, slab / beam system which will
adequately dampen the vibrations.
ii) Dynamic load imposed by screen is considerable and shall be taken into account while
designing the supporting system.
iii) Concrete supporting system is preferred to structural steel for its larger mass that
imparts better dampening quality.
iv) Supporting beams should have a natural frequency greater than 1.5 times the operational
frequency of the machine.
v) Natural frequency condition is generally fulfilled if the length to depth ratio is less than
12.
vi) Beam span to be kept to a minimum.
a) The main supporting element for roof shall preferably be roof rafters, made of rolled
sections or built-up sections, provided at uniform spacing to suit the Junction House.
b) Roof shall have suitable slope (1:5, i.e. 1 Vertical: 5 Horizontal, unless otherwise
specified) to meet technological as well as rainwater drainage requirements.
c) System of bracings shall be provided in the roof top chord and bottom chord levels along
with longitudinal ties to ensure stability and rigidity of the roof structures.
d) Galvanized wind tie (45x6 mm flat) shall be provided at the free edge of roof sheeting.
Suitable arrangement of anchors shall be provided at the ridge of roof sheeting for holding
lanyards of safety belts.
e) For design of roof and side wall frame work, purlins / side runners shall be treated as part
of cladding unit and shall be subjected to local wind coefficients as given in codes.
a) Wall runners with necessary sag rod arrangements shall be provided to support wall and
gable sheeting, including internal partition wall, wherever required.
Vol. – VC STRUCTURAL WORKS Page 13 of 23
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CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION-I (4X210MW)
b) Hanging wall posts shall generally terminate at 2.8 m above ground floor level unless
required to be otherwise.
c) Gables of buildings shall have wall post spaced at intervals to suit bay width
d) Walls shall be provided with louvers and translucent sheeting at appropriate levels, to
provide natural ventilation and lighting.
e) Adequate framing arrangement shall be provided both in roof and side wall framing, for
fixing of ventilator fans / exhaust fans as per requirement.
f) Sheeting on sides and gables shall generally terminate 2.5 m above ground floor level
unless required to be otherwise. Sides below this level shall be generally screened by
brick walls allowing sufficient air inlet to achieve natural ventilation, unless otherwise
required from technological / ventilation requirements.
b) All floor beams of working floors shall be designed for a limiting deflection of span/500
without impact.
c) Beams along-with framework, shall be provided with both horizontal and vertical bracing
(wherever permissible) to achieve overall rigidity.
a) Vertical bracings shall be provided on all column rows for each expansion block.
b) Vertical bracings shall extend from ground level to roof level and shall be designed to
transmit longitudinal forces i.e wind forces, seismic forces, etc. to the foundation.
c) Columns with depth 500 mm or less shall have bracings in single plane at the centre line
of the column. For columns of depth more than 500 mm, bracings shall be provided in
both planes with spacing equal to depth of column. Beam column joints shall be detailed
as per seismic resistant joint with adequate ductility.
b) All walkways and stairs leading to working platforms shall have minimum 1000 mm
width of walkways/flight of stair.
Vol. – VC STRUCTURAL WORKS Page 14 of 23
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TAMIL NADU GENERATION AND DISTRIBUTION
CORPORATION LIMITED (TANGEDCO)
METTUR THERMAL POWER STATION-I (4X210MW)
c) All other walkways and stairs leading to areas for maintenance purpose, or due to
restriction of space, shall have a minimum width of 800 mm of walkway/flight of stair,
unless required otherwise.
e) Staircases shall be generally designed with slope of approximate 37.5 with the horizontal
(in no case the slope shall exceed 40 with the horizontal). All flights of a particular
stairwell shall have same slope.
Intermediate landings shall be provided wherever required such that vertical rise of each
flight does not exceed 3000 mm. Risers in one flight shall be equally spaced.
f) Walkway floors shall be designed with Chequered plate (or non-slip type plates).
g) However all stair treads shall be provided with electro forged gratings of suitable loading
capacity and of approved make.
h) Rise of treads in staircases shall not exceed 200 mm. Width of treads shall not be less than
250 mm.
j) Cat ladders shall be provided for access, wherever provision of staircase is impractical
due to limitations of space, or the access is required very infrequently.
k) Wherever the height of cat ladder exceeds 4.0 m, safety cage shall be provided.
Intermediate landing shall be provided to cat ladders such that vertical height of single
rise does not exceed 8.0 m.
I. For normal cat-ladders, slope shall be within the range of 75-90 with the
horizontal.
II. For ship-type ladders (i.e. cat-ladders with short side handrails) the slope shall be
within the range of 65-75 with the horizontal.
m) All walkways, platforms and stairs shall be provided with safety handrails. All handrails
shall be constructed with steel tubes. The vertical posts shall be located at maximum 1000
mm intervals. The vertical post shall be of 40 NB(M), top rail and mid rail shall be of 32
NB(M) tubes. The toe guard shall be made of skelp. In case of stairs, the toe guards need
not be provided.
n) The vertical height of hand-railings on walkways and stairs shall be minimum 1000 mm
above floor level.
01.03.04.01 Every endeavor shall be made to achieve standardization and uniformity amongst the steel
structures of different units of the plant.
a) Uniform layout module shall be adapted to the extent possible consistent with economy. It
is suggested to adapt a basic module of 3 m for building width and 6 m for column spacing
along building length.
b) Uniform slopes of roofs matching with existing buildings unless specifically required
otherwise for any particular unit.
01.03.05 Documentation
Bidder shall submit the 6 copies of design drawings along with the design calculation &
soft copy of staad input file for the approval of design drawings.
b. After approval of the above, Submit Two (2) prints of each design drawing (supported
by design calculation documents) for Purchaser’s/Consultant’s review/reference as per
the approved schedule, till the drawing is finally accepted. Design drawings shall not be
of greater than A1 size.
On completion of approval of all drawings in any unit, one (1) scanned soft copy on CD
of all approved and stamped design drawings shall be submitted along with the list of
these drawings.
shall either be given part marks or wired on to the main erection mark for
despatch.
The erection clearances for cleat-connected ends of members connecting steel to
steel shall preferably not be greater than 10 mm. at each end. The erection
clearance at ends of beams shall not be more than 20mm. at each end but where
for particular reasons greater clearance is necessary, suitably designed seats shall
be provided.
The fabrication drawings shall be prepared in such a manner that structures are
despatched with maximum transportable lengths and work involved at site is
minimum. Steelwork shall be shop-fitted and shop- assembled as far as
practicable.
All edge preparations for welding shall conform to IS:9595.
The Bidder shall ensure correctness & completeness of fabrication drawings.
The Bidder has to submit the drawings in CD form also for every quarter both for
approval & approved categories.
Approved Steel fabrication & erection drawings (to be submitted directly at site based
on approved Structural drawings).
01.04.01 Drawings
The Bidder shall prepare fabrication drawings, erection drawings, bill of materials,
drawing office despatch lists / shipping documents, schedule of bolts and nuts and as
built drawings based on the approved design drawings. All drawing work shall be in
metric system and all writing work shall be in English.
01.04.02.01 All steel and other materials used for steelwork and in association with steelwork shall
conform to appropriate Indian standards. Only tested materials shall be used unless
written authority is obtained for the use of untested materials for certain secondary
structural members.
a) All rolled sections and plates up to & including 20 mm thickness shall conform to
Grade E250 QUALITY "A” as per IS : 2062-2011.
01.04.02.03 Steel tubes for structural purpose shall conform to IS : 1161 (of Grade Yst 240)
01.04.02.04 Permanent Colour coated (non-insulated) metal sheets shall be troughed (Minimum
depth of trough= 28 mm & Maximum pitch of trough= 205 mm) zinc-aluminium alloy
(55% Aluminium, 43.4% Zinc and 1.6% Silicon) coated, not less than 200 gm/sq m,
having High Tensile sheet (Fy=550 MPa) of thickness commensurate with purlin
spacing adopted, subject to a minimum Base Metal Thickness of 0.5 mm. The sheets
shall meet the general requirement of IS: 15965 and shall conform to class 4 for the
durability.
01.04.02.05 Polycarbonate sheet shall be 3 mm thick of matching profile with metal cladding profile
confirming to IS:14443-1997. The designation/classification of the sheet shall be
IS:14443*PC1S0*LUTN*2520
01.04.02.06 Gutters shall be of copper bearing steel conforming to Grade E250 QUALITY Grade
"A" as per IS :2062-2011.
01.04.02.08 All black bolts, nuts and locknuts shall conform to IS : 1363 and IS : 1364 (for
precision and semi precision hexagonal bolts) of property class 6.4 unless otherwise
specified. Washers shall conform to IS : 6610
01.04.02.09 All tapered washer shall be as per IS:5372 for channels, and IS:5374 for Joists. Spring
washers shall conform to IS:3063.
01.04.02.10 Covered electrodes for arc welding shall conform to IS: 814-2004.
01.04.02.13 Certified mill test reports of materials used in the work shall be made available for
inspection by the Owner / Consultant upon request.
01.04.03 Fabrication
01.04.03.01 Fabrication of all structural steelwork shall be in accordance with IS:800-2007 and in
conformity with various clauses of the Technical Specification.
01.04.03.02 Wherever practicable and wherever perfect matching of parts is required at site,
members shall be shop assembled before despatch to minimise site work. Parts not
completely assembled in the shop shall be secured, to the extent possible, to prevent
damage during despatch.
01.05.01 Scope
The scope of work under erection includes in addition to provision of erection and
transport equipments, tools and tackles, consumables, materials, labour and
supervision, the following:
i) Removal of bends, kinks, twists, etc. for parts damaged during transportation and
handling;
ii) Cutting chipping, filing, grinding, etc., if required, for preparation and finishing of
site connections;
iii) Reaming for use of next higher size bolt for holes which do not register or which
are damaged.
iv) Welding of connections in place of bolting for which holes are either not drilled at
all or wrongly drilled during fabrication.
h) Making arrangements for and providing all facilities for conducting ultrasonic X-ray or
gamma ray tests on welds; getting the tests conducted by reputed testing laboratories,
making available test films/ graphs, reports and interpretation.
i) Rectifying at site, damaged portions of shop primer by cleaning and touch-up paint.
j) Erection of structures including making connections by bolts/high strength friction grip
bolts / welding.
k) Alignment of all structures true to line, level plumb and dimensions within specified
limits of tolerances as per IS :12843 “Tolerance for Erection of Steel Structures”.
l) Application of second coat of primer paint and two coats of finishing paint at site after
erection.
m) Grouting of all column bases after proper alignment of columns and only after obtaining
clearance from Owner / Consultant.
o) Conducting preliminary acceptance and final acceptance tests.
p) Preparation of as built drawings, preparing of sketches/drawings to suit field
engineering decisions, availability of material, convenience of fabrication,
transportation and erection and changes during fabrication and erection.
01.06.01 All steel structural work shall be painted as follows unless otherwise stated in the
drawing / Technical Specification.
The steel surface which is to be painted shall be cleaned of dirt and grease, and the
heavier layers of rust shall be removed by chipping prior to actual surface preparation to
a specified grade.
Grade Sa-2½: This involves very thorough blast cleaning. Mill scale, rust and foreign
matter shall be removed to the extent that the only traces remain in the form of slight
stains. Finally the surface is cleaned with a vacuum cleaner, clean dry compressed air or
a clean brush. It shall then correspond in appearance to the prints designated as Sa 2½.
All paints shall be of approved and shade as per Owner / Consultant's requirements.
Manufacture of paints, mixing of paints, etc. shall be generally according to the relevant
IS codes of practice.
Guarantee period shall commerce from the date of completion of finishing coat of paint
on entire structures. The guarantee period shall be indicated depending on the type of
surface preparation and system of painting. To fulfill this obligations, the Bidder may
obtain from the painting manufacturer, guarantee for the performance of paint/painted
surfaces.
All structures shall receive one coats of primer paint at shop after fabrication before
despatch after surface preparation has been done as per requirements.
Unless otherwise specified all structures after erection shall be given one coat of primer
and two coats of finishing paint of approved colour and quality. The under coat shall
have different tint to distinguish the same from the finishing coat.
The proposed make, quality and shade of paint shall have the approval of Owner /
Consultant’
The bidder shall indicate the estimated quantities of structural items of work ie
fabrication/ erection tonnage , sheeting in sq.m etc. Bidder shall not make any
additional claim if structural quantity of any items required for completion of entire
package as per terms of contract exceed the quantity indicated by the bidder.
TENDER SPECIFICATION
FOR
SEMI DRY FLUE GAS DESULPHURIZATION
(FGD) SYSTEM & ITS AUXILIARIES
VOLUME – VI
MANDATORY SPARES AND TOOLS & TACKLES
MECON LIMITED
RANCHI – 834 002
INDEX TO VOLUMES
Volumes Title
Volume – I Commercial
Volume – II Technical
Volume - IIA General Technical Specification
Section 01.00 Preamble
Section 02.00 Intent of specification
Section 03.00 Project information
Section 04.00 Special instructions to Bidder
Section 05.00 Scope of work, supply & Services
Section 06.00 Quality Assurance system / Requirement
Section 07.00 Painting
Section 08.00 Finalization of sub-vendors / sub-contractors
Section 09.00 Performance Guarantees
Section 10.00 Terminal points & Exclusion
Section 11.00 Layout and maintenance requirement
Section 12.00 Drawings / Documents to be submitted along with Bid / Offer
and after award of contract
Volume - IIB Technical Specification
Section 01.00 Flue Gas Desulphurization System (Semi Dry)
Section 02.00 Technical Data Sheets – Mechanical
Volume -IIC Balance of Plant (BOP) Facilities
Section 01.00 Water Supply System
Section 02.00 Air Conditioning & Ventilation System
Section 03.00 Elevators, Cranes & Hoists
Section 04.00 Fire Protection System
Section 05.00 Piping, Valves & Fittings
Section 06.00 Thermal Insulation, Lagging, Cladding
Section 07.00 Compressed Air System
Volumes Title
Volume - III Instrumentation & Control System
Volume -IV Electrical System
Volume -V Civil, Architectural & Structural Works
Volume -VA Civil Works
Volume - VB Architectural Works
Volume - VC Structural Works
Volume - VI Mandatory Spares and Tools & Tackles
Volume - VII Tender Drawings
01.01 General
The Bidder shall include in his scope of supply all the necessary Mandatory
spares, as indicated hereunder.
01.02 Scope
This section covers the general requirements regarding the mandatory spares and tools
and tackles for all the equipment and systems in the power plant.
The Contractor shall supply in his scope mandatory spares as specified in this Volume.
The supply of mandatory spares shall be started with the consignments of the first unit
and completed before the provisional takeover of the first unit
The Contractor shall supply the Special Tools & Tackles as listed in this Volume.
The supply of Mandatory spares and tools & tackles shall be delivered with the last
consignment of the respective equipment of first FGD unit. The Mandatory spares and
tools and tackles will be handed over at the Purchaser’s stores after the provisional
takeover of the first FGD unit.
01.05 Prices
The itemized Prices of the mandatory spares and special tools and tackles shall be
indicated and the sum total price of mandatory shall be indicated in the respective price
table in Volume I of the Specification
01.06 Detailed Guidelines for Mandatory Spares and Tools and Tackles
a) The Bidder shall supply the mandatory spares and tools and tackles as listed.
b) The Bidder shall give itemized unit price for the spare parts, tools and tackles while
submitting the bid. The Owner reserves the right to modify or delete the items/quantity of
the spares/tools & tackles. The quoted price for taxes & duties, transport, insurance etc.
shall get reduced proportionately to the extent of the value of ordered spares/tools and
tackles. The list of such spares/tools and tackles to be ordered by the Purchaser shall be
finalised by the Owner before signing of the Contract.
c) In case the description / nomenclature of any of the items of spares/tools and tackles is
differing from the description / nomenclature indicated in the list of mandatory
spares/tools and tackles, the bidder shall offer functionally equivalent part in lieu of the
listed item.
d) In case if such items of spares/tools & tackles indicated as “not applicable”, are found
applicable at a later date during execution of the project, such items of spares/tools &
tackles are to be supplied within the ordered cost of the mandatory spares.
e) If any of the items of spares/tools & tackles ordered is found to be not applicable during
detailed engineering stage/execution stage, the contractor shall have to supply alternative
items of spares/tools & tackles. The alternative items of spares/tools & tackles are to be
mutually agreed between the Owner and Supplier.
f) In respect of quantity mentioned as 'Set' means the total quantity of all the
components/items used in particular equipment unless otherwise specified.
Example-1
One set of spare part which is having four different items of which first item is having 2
similar parts, second one is having 3 similar parts and other two are having one part each,
then one set means, combination of 2 similar parts of first item and 3 similar parts of
second and one each of 3rd & 4th items.
Example-2
If the quantity of particular spare part is more than one, set means the total no. of similar
parts.
g) Wherever % is indicated for the mandatory spares, the quantity shall be calculated for %
of supply for total quantity for 2 units, unless otherwise specified. The quantity to be
reckoned for % indicated shall be rounded off to the next higher whole number. For
example if the % arrived is 0.2 the quantity to be supplied shall be 1 and if the % arrived
is 5.1 the quantity to be supplied shall be 6.
h) All relevant drawings to identify of spares/tools & tackles are to be furnished when called
for by the OWNER.
This above details shall be applicable for electrical, C & I and Civil system also.
S. No Description Quantity
1.0 Complete set of CEMS 10% of total quantity or 1 no. whichever is
analyzer more (for each Make, Type/Model)
2.0 PLC Controller, I/O cards 10% of total quantity or 1 no. whichever is
(AI,AO,DI,DO) more (for each Make, Type/Model)
communication Modules,
Interfacing cables etc
3.0 OWS,EWS – Computer CPU 10% of total quantity or 1 no. whichever is
and accessories like Monitor, more (for each Make, Type/Model)
key board, Mouse, SMPS,
Hard disk, etc
4.0 Different field instruments like 10% of total quantity or 1 no. whichever is
Transmitters (press., flow, more (for each Make, Type/Model)
temp, level), switches, Gauges,
indicators, Thermocouples,
RTDs, Vibration pick ups, root
valves etc.
S. No Description Quantity
1.0 Floor Mounted VCB (7.2kV, 1 No.
2000A, 40kA) (one to one
interchangeable)
2.0 Bushing CTs, Core balance 1 Set
CTs, Relays, Meters, Surge
absorbers etc.
TENDER SPECIFICATION
FOR
SEMI DRY FLUE GAS DESULPHURIZATION
(FGD) SYSTEM & ITS AUXILIARIES
VOLUME – VII
TENDER DRAWINGS
MECON LIMITED
RANCHI – 834 002
INDEX TO VOLUMES
Volumes Title
Volume – I Commercial
Volume – II Technical
Volume - IIA General Technical Specification
Section 01.00 Preamble
Section 02.00 Intent of specification
Section 03.00 Project information
Section 04.00 Special instructions to Bidder
Section 05.00 Scope of Work, Supply & Services
Section 06.00 Quality Assurance system / Requirement
Section 07.00 Painting
Section 08.00 Finalization of sub-vendors / sub-contractors
Section 09.00 Performance Guarantees
Section 10.00 Terminal Points & Exclusion
Section 11.00 Layout and Maintenance Requirement
Section 12.00 Drawings / Documents to be submitted along with Bid / Offer
and after award of contract
Volume - IIB Technical Specification
Section 01.00 Flue Gas Desulphurization System (Semi Dry)
Section 02.00 Technical Data Sheets – Mechanical
Volume -IIC Balance of Plant (BOP) Facilities
Section 01.00 Water Supply System
Section 02.00 Air conditioning & Ventilation System
Section 03.00 Elevators, Cranes & Hoists
Section 04.00 Fire Protection System
Section 05.00 Piping, Valves & Fittings
Section 06.00 Thermal Insulation, Lagging, Cladding
Section 07.00 Compressed Air System
Volumes Title
Volume - III Instrumentation & Control System
Volume -IV Electrical System
Volume -V Civil, Architectural & Structural Works
Volume -VA Civil Works.
Volume - VB Architectural Works
Volume - VC Structural Works
Volume - VI Mandatory Spares and Tools & Tackles
Volume - VII Tender Drawings
TENDER DRAWINGS
WATER
1
I
(FABRIC FILTER)
GATE GATE GATE
ABSORBER
B B DAMPER DAMPER DAMPER
BY PRODUCT
SILO
4 2
PROCESS
WATER
NOTE-5
TANK
PROCESS WATER
SUPPLY PUMPS
2x100% RECIRCULATION LINE
I
EXISTING NOTE-3
STACK PDT
NOTE-4
B AT
SO2 GATE
DAMPER
1
B I
SILO VENT
DUST FILTER
BY PRODJCT
DISCHARGE
AIR BY PRODUCT
SILO
(PENUMATIC
SILO VENT CONVEYING)
DUST FILTER
3
3
BIPLANE
DAMPER NOTE-2
TC
BIOLER
CONTROL
SILO VENT
DUST FILTER
DISCHARGE TERMINAL POINT
A B A HYDRATED
LIME
BOILER SILO B
FOR EACH
UNIT
SILO VENT B
B B B (7 DAYS) DUST FILTER
STORAGE AIR LIME
BIPLANE BOOSTER BIPLANE CARRYING TRUCK
ID FAN DAMPER DAMPER
COMPRESSED AIR 3
FAN FOR FGD PLANT (BY OTHERS)
3
DUST FILTER
SILO VENT
B
SURGE BIN
SERVICE WATER FROM 1x100%
EXISTING PLANT
COMPRESSER AIR
B FOR FGD PLANT
SERVICE WATER
TANK TO PLANT SERVICE GRAVIMETRIC
WATER RQUIREMENT FEEDER
2x100%
SERVICE WATER
TRANSFER PUMPS
FEEDER
2x100%
3
AIR
MECON LIMITED
PDT
PDT
1
GATE
(FABRIC FILTER)
DAMPER GATE GATE GATE
DAMPER DAMPER DAMPER
SPRAY DRYER
ABSORBER
(PNEUMATIC
CONVEYING)
SILO VENT
STACK DUST FILTER AIR
HYDRATED
LIME
SILO VENT
STORAGE B
SILO DUST FILTER
AT
B SO 2 (7 DAYS)
STORAGE B
1
LIME
B CARRYING TRUCK
GRAVIMETRIC (BY OTHERS)
FEEDER
2x100% 2 SILO VENT
(PNEUMATIC DUST FILTER
AIR CONVEYING)
2
3
SLAKING
BY PRODUCT
WATER
SILO
LIME
SLAKER
2x100%
TC
A A
B
BOILER
LIME SLURRY PUMP
B
2x100% B
B B
BIPLANE BOOSTER BIPLANE SERVICE WATER FROM
ID FAN DAMPER DAMPER EXISTING PLANT
FAN B
COMPRESSED AIR
SERVICE WATER
FOR FGD PLANT
TANK TO PLANT SERVICE
WATER RQUIREMENT
SERVICE WATER
PROCESS TRANSFER PUMPS
WATER FROM 2x100%
EXISTING PLANT B
COMPRESSER AIR
FOR FGD PLANT
PROCESS
WATER TANK 3
PROCESS
WATER SUPPLY PUMPS
MECON LIMITED
IS
O ny
90 pa
01 Com