Dilla Unv Ethio-Engineering

Design of spreader beam rigging Dilla university final
internship report and project
DILLA UNIVERSITY
COLLEGE OF ENGINEERING AND TECHNOLOGY
SCHOOL OF MECHANICAL AND AUTOMOTIVE
ENGINEERING
DEPARTMENT OF MECHANICAL ENG.
HOSTING COMPANY:
Ethio-engineering Group Power Equipment Manufacturing
Industry [EEGPEMI]
From February 2020 to December 2020
Name: Ephrem Milion
Submitted date: MARCH 03/2021 GC
BY EPHREM MILION
2021 GC
i
Design of EOT crane with spreader beam rigging Dilla university final internship and
project
DECLARATION
I Am 4th year mechanical Engineering student in Dilla University declare that
this report is my original work based on the past consecutive four month’s
internship program from February 2020 to December 2020 at Ethio-engineering
Group Power Equipment Manufacturing Industry.
In doing so, assuring that I agree with all written above with signature as follows.
Name signature
Ephrem Milion __________________________
This report has been approved by my supervisor and mentor:
In his stay in our company he has been excellent in performing work tasks
accurately and on time. He also developed team playing skills, communication
skills and work ethics. To the best of his knowledge and as per his declaration, the
report is an authentic work on the issue and has not been submitted to anywhere.
Approved by
Supervisor name -Teketel T. Approved On Internship Project Proposal
BY EPHREM MILION 2021 GC

ii
project
Acknowledgement
Words are in adequate to compensate the help of God and a great many people.
Firstly, I would like to thank Dilla University department of mechanical
engineering for its opportunity providing role and support. I would like to
appreciate the engineer’s cooperation their presence for consultation in their office
and work shop. I would like to express my deepest gratitude and appreciation to
my advisor Mr.Markos k.whose suggestions and encouragement helped me to
coordinate and conduct this internship project and report. The next thanks go to
brotherly supervisor Tewodros for his best advice and follow up helped me a lot. I
would like to express my deep sense of gratitude and appreciation to the workers
of transformer body manufacturing mechanical shop and electrical workshop that
helped me to acquire lots of knowledge and practices throughout my stay. My last
thank goes to Ethiopian Power Engineering Industry who made any type of
contribution in my performance of this internship session.

iii
project
Executive summary
The report focusses on describing the company’s history, services that the
company gives to the society, the organizational structure. Furthermore, it focuses
in describing the process of making transformer and specifically the body
manufacturing of transformer. With this regard, I have been working in Ethio-
engineering Group Power Equipment Manufacturing Industry, under Power factor
corrector, compact Distribution sub-station factory, which is responsible for the
production of Compact distribution substation, it is an integration of HV, LV
switchgear and transformer, also for the last two months I have been working in
transformer factory, which is found on tatek so it contains technical things about
transformers. In addition to this, it deals about the benefit that I gain from the
internship program in regarding of the practical and theoretical knowledge. Not
only this but also, I understand about the leadership, entrepreneurship and the
communication skills at. Finally, the challenge that I faced in the internship, the
solution taken to solve the challenges, problem identification and solution for the
problem is also described.

iv
project
Contents
CHAPTER ONE ........................................................................................................1
BACKGROUND OF ETHIO-ENGINEERING GROUP POWER EQUIPMENT
MANUFACTURING INDUSTRY ........................................................................1
1.1 History of EEGPEMI ....................................................................................1
1.2 Main products ................................................................................................2
1.3 Main customer of the factory ...........................................................................3
1.4 Organization flow .............................................................................................4
1.5 Work Flow ........................................................................................................5
CHAPTER TWO ....................................................................................................6
OVERALL INTERNSHIP EXPERIENCE............................................................6
2.1 The way I get into the company ....................................................................6
2.2 The Section of the Company I have worked in .............................................6
2.2.1 Sections in Power factor corrector, compact Distribution sub-station
Factory (saris) .........................................................................................................6
2.2.2 Sections in Tatek-Transformer Factory .........................................................8
ELECTRICAL SECTION ......................................................................................8
MECHANICAL SECTION .....................................................................................10
2.3 flow of the sections......................................................................................15
2.4 Work tasks you have been executing ..........................................................16
2.5 The procedures I have been using while performing work tasks ................16
CHAPTER THREE ..............................................................................................17
OVERALL BENEFITS GAINED FROM INTERNSHIP ..................................17
3.1 In terms of improving practical skill ..............................................................18
3.2 In terms of upgrading theoretically knowledge..............................................18
3.3 In terms of improving interpersonal communication skill .............................19
3.4 In terms of improving team playing skill .......................................................19
3.5 Improving Leadership skills ...........................................................................20
3.6 Understanding work ethics related issues ......................................................20
3.7 Improving entrepreneurship skills ..................................................................21
CHAPTER FOUR ....................................................................................................21
PROJECT DESIGN .................................................................................................21
4.1 DESIGN OF OVERHEAD CRANE WITH SPREADER BEAM RIGGING
..................................................................................................................................21
Literature review ......................................................................................................21
Bridge girder .....................................................................................................23

v
project
Mechanisms ..........................................................................................................27
ABBREVIATION ....................................................................................................30
4.1.1 Significance of EOT with spreader beam .......................................................33
4.1.2 Problem statement ...........................................................................................33
4.2 Objectives...........................................................................................................33
4.2.1 Main objective.................................................................................................33
4.2.2 Specific objective ............................................................................................33
4.3 Advantage of the project ....................................................................................33
4.5 Major parts of an EOT crane .............................................................................34
4.8 Advantages of Using a Spreader Beam .............................................................34
CHAPTER FIVE......................................................................................................35
DESIGN OF COMPONENTS ..................................................................................35
5.1 Design of Rope...................................................................................................35
5.3 Over all dimension of the trolley .......................................................................39
5.4 Design of bridge girder ......................................................................................40
5.5 Design of spreader beam rigging ....................................................................47
5.5.1 How spreader beam reduces horizontal forces? .............................................47
5.5.2 Loads on the Spreader Beam ..........................................................................48
5.6 Design of End carriage.......................................................................................51
5.6.1 Calculation of the loads that act upon the end carriages ...........................51
5.6.2 Conclusion and recommendation....................................................................56
5.6.3 Reference ........................................................................................................58
Appendix...................................................................................................................58

vi
project
LIST OF TABLE OF FIGURE

Figure 1 Low voltage switchgear .................................................................................................... 2
Figure 2 33kv High voltage switchgear ...................................................................................... 2
Figure 3 Transformers..................................................................................................................... 3
Figure 4 organization flow .............................................................................................................. 4
Figure 5 Work flow ....................................................................................................................... 5
Figure 6 bending machine ............................................................................................................... 7
Figure 7 CNC TURRET punching machine ................................................................................... 7
Figure 8 shearing machine .............................................................................................................. 8
Figure 9 winding machine .............................................................................................................. 9
Figure 10 CNC plasma cutter ....................................................................................................... 11
Figure 11 Drilling machine ........................................................................................................... 11
Figure 12 Rolling machine............................................................................................................ 12
Figure 13 arc welding ................................................................................................................... 13
Figure 14 lathe machine ................................................................................................................ 15
Figure 15 flow of the sections ...................................................................................................... 15
Figure 16 Sectional view of an EOT crane ................................................................................... 23
Figure 17 A typical bridge girder.................................................................................................. 23
Figure 22 spreader beam with sling ............................................................................................. 26
Figure 23 spreader beam ............................................................................................................... 26
Figure 18 Hoisting assembly ....................................................................................................... 28
Figure 19 Cross travel mechanism ................................................................................................ 28
Figure 20 Single girder cranes ...................................................................................................... 29
Figure 21 Double girder crane ..................................................................................................... 30
Figure 24 Cross travel wheel ........................................................................................................ 38
Figure 25 Overall dimension of the trolley ................................................................................... 39
Figure 26 spreader beam without load .......................................................................................... 47
Figure 27 spreader beam with transformer .................................................................................. 48
Figure 28 Plan view of a section of a crane .................................................................................. 51

Design of spreader beam rigging Dilla university final
internship report and project
CHAPTER ONE
BACKGROUND OF ETHIO-ENGINEERING GROUP POWER
EQUIPMENT MANUFACTURING INDUSTRY
1.1 History of EEGPEMI

Currently the Federal democratic republic of Ethiopia has given a special attention
to electrification especially for electric power generation, transmission and
distribution to make and ensure Ethiopian electric power management more
reliable and support the economy. To overcome electricity distribution problems
and to support the economy of the country EPEI plays high and beneficial role.
Ethiopian Power Engineering Industry is one of the biggest industries established
under metal and engineering corporation (METEC), now its name is changed to
Ethio-engineering group power equipment manufacturing industry (EEGPEMI)
Which includes six factories under it namely;
 Transformer Factory (AA TATEK)
 Cable and Wire Factory (MOJO)
 Power factor corrector, compact Distribution sub-station and Motor control
center Factory (AA SARIS)
 PCC & MCC Shop (AA SARIS)
 Motor & Generator Factory (BATU)
 Solar Energy Factory (SANDAFA)
 Engine Factory (MEKELLE)
I have been working in EEGPEMI under two companies Power factor corrector,
compact Distribution sub-station and Motor control center Factory (CDSS) (AA
SARIS) and Transformer Factory (AA TATEK), both companies work
together.
BY EPHREM MILION
2021 GC
2
project
1.2 Main products
 Power factor corrector, compact Distribution sub-station and Motor

control center Factory (AA SARIS)
In this factory the main product is compact distribution substation, it is an
integration of HV, LV switchgear and transformer, based on the user’s selected
distribution scheme to complete assembly of distribution substation in the
factory. It is a power distribution compartment which is an incoming voltage
(15kv or 33kv) inputted to high voltage side and out putted at low voltage side
by step down transformer located between HV and LV.
Figure 1 Low voltage switchgear

Figure 2 33kv High voltage switchgear
Transformer Factory (AA TATEK)

3
project
TATEK Transformer production Factory produces different KVA rating power

distribution Transformer. A transformer is considered a passive device capable of
storing and delivering finite amounts of energy. Practically all transformers utilize
magnetic material for shaping the magnetic fields which act as the medium for
transferring energy. The relationship between the magnetic-field quantities and
electric circuits with which they interact play an important part in describing the
operation of the device. The magnetic material determines the size of the
equipment, its capability, and introduces limitations because of saturation and loss
on the performance. Essentially, a transformer consists of two or more windings
interlinked by a mutual magnetic field. These windings are simply coiling of wires,
inductors.
In TATEK transformer production factory there are eight shops to manufacturing
transformer such as; Body production shop, Insulation production shop, Winding
production shop, Core production shop, core/ coil assembly and Connection shop,
Final assembly shop, Oil filling shop and final testing shop.
Figure 3 Transformers
Main supplier of the production factory Dubai Emirate, China, METEC different
industries, Tabor ceramic
1.3 Main customer of the factory

 Ethiopian Electric Utility
 Telecommunication
 Privet sector

4
project
1.4 Organization flow
Factory
Manager
Secretary
Deputy
Manager
Engineering Store production

Section
Body
shop
Maintenanc Productio Documentatio Quality Design Cost
e n plan n control Windin
Inventory g shop
control
Process Product Core

Production Production
Design Design cutting
planning control
Assemb
Electrical Mechanical ly shop
design design
Figure 4 organization flow

5
project
1.5 Work Flow
Figure 5 Work flow

6
project
CHAPTER TWO
OVERALL INTERNSHIP EXPERIENCE
2.1 The way I get into the company

First of all, Ethio- engineering group power equipment manufacturing (EEGPEMI)
head office is around lebu mebrat so I sent internship request paper in human
resource office. After one or two months later, they accepted me then they assign
me to work in Power factor corrector, compact Distribution sub-station Factory in
saris. After working two months I had a break because of COVID 19. When I have
begun the internship again, I started working in tatek transformer factory which is
the main branch of EEGPEMI because there are limited works in saris’s factory
specially on the mechanical shop. So, this is the way how I get in the company.
2.2 The Section of the Company I have worked in
As I mentioned in the above, I have been working in two factories which are
controlled and commanded by one head office. So, I have been working in
different sections in each company.
2.2.1 Sections in Power factor corrector, compact Distribution sub-station
Factory (saris)
I have been working in this factory on some sections, here in this factory the
primary product is Compact distribution substation (CDSS), it is an integration of
HV, LV switchgear and transformer, based on the user’s selected distribution
scheme to complete assembly of distribution substation in the factory. So, in this
factory the main section is compartment making section under this section there
are many sub sections they are mentioned below;
 Bending
Here in this factory the row material is sheet metal, we use these metals to make
the enclosure for CDSS. In order to make this compartment or enclosure we need
to shape the sheet metal so we use bending machine to bend the sheet metals in
different shapes with desired angle.

7
project
Figure 6 bending machine

 Punching
In this sub section, we cut out the metal sheet in different shape. This machine is
called CNC TURRET PUNCH machine. it punches, cut, drill metal plates with any
design. It has Electric SERVO Control for fast ram punching performance with 30-
ton capacity. Precise ram positioning control, with an accuracy of 0. 01mm.this
machine is digitally controlled machine.
Figure 7 CNC TURRET punching machine

 Shearing
It is where the sheet metal is cut with desired measurements by using
shearing machine itis digitally controlled machine.

8
project
Figure 8 shearing machine

 Painting
It is the final section where the enclosure is painted and to be ready for the housing
the CDSS.
 Testing
It is the main and the important section of CDSS production, here in this section
we take many tests for instance no load test, open circuit test, on load test on the
transformer and on CDSS.
2.2.2 Sections in Tatek-Transformer Factory
In this factory the main product is distribution transformer. There are two big
sections here in this factory they are Electrical section and mechanical (body work-
shop) section.
ELECTRICAL SECTION
It is where the electrical parts are installed so, there are many sub sections under
this main section. They are;
 Insulation
This section is the main and the important section for making transformer. Here in
this section where insulator materials are formed. Those materials are made up of

9
project
different size papers and woods. We use insulation for almost all transformer
making system or processes. Most works here are cutting the insulator materials in
different size and shapes in order to make it simple to insulate the materials which
are in the transformer.
 Winding
It’s where winding or turning of copper wire is formed, we done this process by
using manually operated winding machine. In this section we have two stages;
Primary winding
In step down transformer the primary winding has large number of turns. Its where
the high voltage is supplied to the transformer. In this section we also get out taps.
Secondary winding
Here the applied voltage in secondary coil smaller than the primary voltage, this
means that the voltage is stepped-down. Here the winding wire is thick and larger
than the primary winding wire. And it has smaller number of turns.
Figure 9 winding machine

 Core making section
In this section where core is made and we use iron silicon alloy (97%iron 3%
silicon).so in order to make the core there are procedures, Core cutting section,
Core assembling section, Core testing section.
 Core and winding assembling
In this section we assemble the core and the winding, this means that we insert the
winding into the core. So, we use three winding coils for one transformer because
it is three phase transformers.

10
project
MECHANICAL SECTION
Transformer body production

Here in this section the transformer body is produced by using sheet metal there
are many stages for making the body and the machine that used to make it, this
process is located in mechanical workshop section.
There are several steps for the transformer body being produced, explained below
Raw material entry
A raw material for transformer body is sheet metal made of mild steel. which
thickness is vary depend on the transformer power. Mild steel contains 0.15% to
0.3% of carbon contain, and it is used very extensively for structural work. The
main reason to choose mild steel is it has better weldability than other alloys.
Sheet metal forming
The sheet metal which is checked by the laboratory to fulfill the minimum standard
enter to the body workshop. Then it goes via different sheet metal forming.
 Cutting
Cutting of sheet metal is accomplished by a shearing action between two sharp
cutting edges. Shearing is used to cut large sheets into smaller sections for
subsequent press working operation.
Cutting by hydraulic pendulum CNC plate shear
The mild steel sheet metal is cut by hydraulic CNC shear machine into desired
shape or width and length. If the thickness is more than the machine can handle the
sheet metal can be cut by CNC plasma cutter. Mostly the hydraulic pendulum CNC
plate shear manufacturers suggest to shear maximum of 20mm thickness and for
the plasma to 120mmof mild steel sheet metal.

11
project
Figure 10 CNC plasma cutter
 Drilling
Drilling is used to create a round hole. It is accomplished by a rotating tool that
typically has two cutting edges. The tool is fed in a direction parallel to its axis of
rotation into the work part to form the round hole. In transformer body forming
there are many holes starting from small hole to a big one. Those which are bigger
are drawn or drilled by a plasma cutter.
Figure 11 Drilling machine

12
project
 Bending
Bending in sheet-metal work is the straining of the metal around a straight axis,
during the bending operation, the metal on the inside of the neutral plane is
compressed, while the metal on the outside of the neutral plane is stretched.
In transformer body forming sheet metals are bend as need by the design by using
a hydraulic CNC bending machine. This machine can be bend up to a thickness of
14mm. mostly this machine performs V bending.
Fines are form in a specially designed machine called hydro-pneumatic corrugated
machine which bend and stretch metal into a designed height and width.
 Rolling
This is a compressive deformation process in which the thickness of a slab or plate
is reduced by two opposing cylindrical tool called rolls. The rolls rotate so as to
draw the work into the gap between them and squeeze it. Sheet metal for
conservation is rolled by a roller machine.
Figure 12 Rolling machine
 Welding
Welding is a metal joining process in which two or more parts are joined or
coalesced at their contacting surface by suitable application of heat or/ and
pressure. In some welding processes a filer material is added to facilitate
coalescence.

13
project
In transformed body workshop there are different type of welding’s are take place.
Those are arc welding, oxy acetylene, MIG,TIG those are the most common ones.
Figure 13 arc welding

o Arc welding: arc welding refers to a group of welding processes in
which heating of the metal is accomplished by an electric arc. In
transformer body most structures are welded by this type of welding.
o Oxy-acetylene welding: these joining processes use oxy-fuel gas, such
as mixture of oxygen and acetylene, to produce a hot flame for melting
the base metal and filler metal, if one is used. In transformer body this
welding type is used for fin side alignment in case TIG welding is not
work.
o Metal inert gas (MIG): here in which the electrode is a consumable bar
metal wire, and shielding is accomplished by flooding the arc with a gas.
The bare wire is fed continuously and automatically from a spool through
the welding gun. In transformer body this welding type is used for
joining the fines with main transformer body with high accuracy.
o Tungsten inert gas welding (TIG): is an arc welding process that uses a
non-consumable tungsten electrode and an inert gas for arc shielding.
The term TIG welding is often applied to this process. TIG can be
implemented with or without a filler metal.

14
project
 Grinding
Grinding is generally called as fine machining or finishing operations of
removing materials from surface usually 0.25- 0.5 mm in most operation
through the use of grinding wheel. It may be used to finish almost all surface,
which has been previously roughly shaped by some other or processes or
remove the extra material which is too hard to be removed by other machining
processes.
 Inspection and painting
After transformer body is finished it must be passing through the inspection
process to check up if there is any leakage. This process is done by using
compressor and detergents. If there is any leakage found in transformer body it
will be welded again. After inspection it goes to final process of painting and
galvanizing.
 ?Other processes
There are other processes which are under taken by lathe machine which is used
to make hollow like structure of the cup for pouring the oil in the conservator.
And the other process is bending of tube in some manual machine to bend the
tube which is used to join the conservator and the breather. Final in case of
drilling and cutting if the thickness is large to cut or drill by hydraulic CNC
cutting machine and hydraulic drilling machine respectively, we use a plasma
cutter to cut and drill large thickness and wide diameter.
Generally, I get good experience here in mechanical workshop. In this
transformer body shop many processes are done. To have one transformer body
it passes through cutting, bending, welding, rolling, grinding, painting and
drilling are major processes. To have an effective transformer body every parts
must be done with accurate position and angle.

15
project
Figure 14 lathe machine
2.3 flow of the sections
insulation Cutting stage

making stage
bending
winding stage
drilling
core making
stage welding
core and winding

assembling inspection and painting
Insertion of core and winding into

transformer body
Figure 15 flow of the sections

16
project
2.4 Work tasks you have been executing

In Power factor corrector, compact Distribution sub-station Factory there are
limited works so not all machine was working. So, I have been working on
punching machine by making some simple designs using CAD. I also work on
shearing machine and cut some metal sheets.
In Tatek transformer factory there were many work tasks some of them are;
 Cutting of insulation papers into different shapes
 Winding of copper wire both primary and secondary windings
 Cutting of core metal in different shape and arrange them properly
 Insertion of winding coils into the core
 Making electrical connection (star-delta connection)
 Putting the core and the winding assembly into transformer.
 Testing of the transformer.
2.5 The procedures I have been using while performing work tasks
During my internship period I have seen that there are brief procedures that we
follow;
 The first thing is safety of workers so, closed shores are must and working
clothe.
 Steps to turn on the machine
 Turn on the machine
 Start the motor
 Put the machine in desired mode (automatic or manual mode)
 The following are steps that we follow when the fault is happened in the
machines;
 Turn off the machine
 Make switch off circuit breaker
 Make grounding for safety during maintenance.
 Trace fault
 Then identify problem and maintain it
 After the technician maintenance, Ground will be disconnected
first.

17
project
 Make switch on the circuit breaker

2.6 How good am I in my working task?
I was good in every section of my work. I have been tried to communicate with my
co-workers and we work together also they teach me many things specially how to
do things safely. I have been doing my best without being exhausted by keeping
work ethics being punctual and also by respecting each other during my internship
period.
2.7 Challenges I have faced
The first challenge I have been facing is the distance of the transformer factory
from my home is too far so I have to get up early to arrive on time. The second
challenge I have been facing there is no cafe and restaurant around company.
2.8 The measure taken in order to overcome these challenges

The first thing I have do to overcome the challenge is by getting up early and take
the companies service bus. For the second problem I pack my own food and eat in
the factory.
CHAPTER THREE
OVERALL BENEFITS GAINED FROM INTERNSHIP
Internship program is a method of letting the students to assume themselves

as potentially responsible workman for a particular work by assigning them to
actively participating in production control as well as maintenance in industrial
company. And such trends help to have valuable work experience. Internship
programs are also potentially valuable to the company. In this internship, I have
observed what the outside industrial world looks like more than the regular classes.
In this internship, I have got good opportunity to face difficulties in the real world.

18
project
The overall benefits of internship are not limited to the practical skill only. The
overall benefits that I have gained in terms of different daily activities. Such as:
 Upgrading theoretical knowledge

 Entrepreneurship skill
 Increasing communication skill
 Become better in practical skills
 Improving leadership skill
 Get more knowledge about ethics related issue
3.1 In terms of improving practical skill

Since from lower grade our mind loaded with theoretical concepts even in campus.
Having a good practical skill is not that much available due to lack of materials
but, in this internship, program have got lots of practical skills and experiences.
Also, it can assist students to bridge the gap between the academic learning process
and the Practical world. There are many benefits that we get from our internship
program. These includes: -.
 Controlling of large machines (shearing, lath, bending and drilling

machines)
 How to weld different metal with different welding methods
 Arrangement of equipment in the workshop
 How to use working materials
 Develop the habit of safe working.
3.2 In terms of upgrading theoretically knowledge

This internship program provided chances to build intellectual knowledge and
practical skills. I have been familiarized with different types of machines such as
shearing machine, lath machine, bending machine, CNC machines, winding
machines and CNC plasma cutting machines which helped to have a better
19
project
understanding on what I have learned in class. Internship program is not only used
to improve practical skill, but also used to impose theoretical knowledge by
correlating the practical skill with theoretical knowledge. The appropriate
measures we undertake to improve theoretical knowledges are:
 To know what system the machine, use to work, also its controlling system.
 To know the details parts of the machine one by one.
3.3 In terms of improving interpersonal communication skill

Communication skill can involve one to one conversations or individuals
interacting with many people within a society. It also helps us to understand how
and why people behave and communicate in different ways to construct and
negotiate a social reality. Company that I have been involved in has different
people with various background came together. They are can vary in educational
level, economic situations, cultural backgrounds, life standards and etc. Since the
aim of the company is to accomplish the work in good way, to have good
communicative skills is important. During internship time, I have improved
communication skill by communicating starting from daily labor to project
manager learning different type of production terms.
3.4 In terms of improving team playing skill

When different individuals come together to work for common goals of the
company for increasing productivity, the most important point is just reaching an
agreement on different points on the work to be done at a time. A person with good
team playing skill will upgrade the following:
 To help and co-operate with others

 To give comment to the team
 To demonstrate reliability

20
project
 To treat others in respectful and supportive manner

 To increase the ability of active participant
 To become a problem solver on time
3.5 Improving Leadership skills

Leading a team or an organization holds the most basic and key place of
profession, hence requires well trained person. We have learned a good leading
skill from our supervisor and all be responsible and trusted. The engineers that we
work together some of the leader ship skills that we have performed are:
 To share our problems openly and get the team involved in solutions
whenever there is a setback.
 As a leader to be clear, active by working, to have goals, mission and vision
in our ability.
 During our working time, always ready to show smiley face for the workers
and supervisor.
 Respecting differences of all team members.
 Listening and accepting the ideas of our supervisor.
 To recognize, tell and solve mistakes and problems
3.6 Understanding work ethics related issues

Work ethics is a system of values in which central importance is described to work,
or purposeful activity, and to qualities of character believed to be promoted by
work. EEGPEMI workers and interns through the following work ethics.
 Punctuality: This means arriving at work on time

 Honesty: Honesty at work means spending working hours and resources
totally on work

21
project
 Willingness to learn: This means understanding the way things are done at
your work place and trying to do it better
 Initiative: Being prepared to see what needs doing and to do the work
without always being asked or told to do it
 Loyalty: Do what best for the growth of the organization
 Maximizing productivity: This is the ability to do high quality work faster
and efficiently.
3.7 Improving entrepreneurship skills

Entrepreneur means undertake the risk of new enterprises. This creation called
entrepreneurship. Being an intern student built an individual’s knowledgeable in
Selection of the effective way of doing work and develops entrepreneurship skills.
In this company we understand the following point which is related to the
entrepreneurship.
 Risk taking ability.

 Increasing efficiency of work.
 Able to invent new ideas.
 Creative mind in solving the problem of company and Work discipline.
CHAPTER FOUR
PROJECT DESIGN
4.1 DESIGN OF OVERHEAD CRANE WITH SPREADER BEAM RIGGING
Literature review
Beginning from the times that industrial development has changed from the
small to big industries, materials handling has played a crucial role in the

22
project
transportation of raw materials and finished products of the industries. And up till
now this field continues to be a very important part in industries. No modern
industrial plant would be conceivable without efficiently and organized materials
handling systems.
There are different types of materials handling equipment in practice. These are
continuous intermittent materials handling equipment. In this report an intermittent
materials handling equipment called overhead traveling crane will be discussed in
detail.
Overhead traveling crane with spreader beam rigging is one type of crane that most
people would recognize as a workshop or a factory crane. Although considerable
advances in design have been made over many years, the fundament concept has
not changed much.
Overhead crane,also known as bridge crane or EOT crane,is a crane equipment
which is installed across the workshop,warehouse and yard for material lifting.
The two ends of crane sit on tall concrete pillars or metal supports,its shape like
bridges.
A spreader beam is a simple device consisting of a long bar that holds two slings
apart. It’s designed to convert lifting loads into pure compressive forces and also
spread apart the legs of a sling.
Spreader beams mainly reduce horizontal forces and convert lifting loads into
compressive forces in the beam and tensile forces in the slings.
1In our environment, it is hard to lift or transfer a heavy object from one place to
another. To solve this problem, cranes are commonly employed in industries
either in domestic industries or warehouse. For example, crane is used in
industry for the transportation, loading and unloading of equipment, in the
construction industry for the movement of materials and in the manufacturing
industry for the assembling of heavy materials.
There are several components of the overhead crane that manufactured before
Bridge girders Motors

End carriages Brakes
23
project
Trolley Pulleys
Hook Wheels
Rope Electrical components
Gear boxes
Figure 16 Sectional view of an EOT crane
 Bridge girder
Figure 17 A typical bridge girder

Crane girders are made from structural shape box sections fabricated from steel
plate. They are designed to resist all vertical, horizontal and tensional forces.
Girders may be of symmetrical or asymmetrical design (different plate thickness

24
project
for top and bottom plates) Trolley rail sections may be welded or bolted with fish
plates to top plate directly. Maximum allowable vertical deflection due to live load
should also be limited.
Girders should be fabricated using high penetration continuous welding. Trolley
rails or crane rails on double girder cranes should be high strength steel bars
capable of carrying trolley wheel loads with a minimum wear.
 End carriages
End carriages are part of the crane that carries the whole crane body including the
trolley.
 Trolley
It is a steel frame carrying the hoist mechanism and cross travel mechanism.
Trolley wheels should be cast and machined from spherical graphite nodular
material for best wear characteristics.
 Hook
Crane hooks are used on the cranes to hoist materials. For load handling
applications they are in the form of letter ‘C’ with a shank for mounting the
bearing and a threaded portion for fixing the nut. Generally the hook is made by
forging. It can be manufactured with the specification of the load to be lifted, the
dimension of the rope, no of falls and acceleration of the hook.
The hook assembly consists of

1. Hook
2. Thrust bearing for taking the vertical load
3. Cross-pieces for supporting the thrust bearing
4. Radial bearing for the turning of the hook abut vertical axis
5. Nut for fixing the hook at the top

25
project
 Rope
Rope is one of the most important parts of a crane. As opposed to traditional ropes
which are made of vegetable fibers (also called hemp), all engineering applications
such as hoists and cranes use ropes made of steel wires and a core of hemp or steel.
 Brake
In hoisting machinery brakes are employed for controlling the speed of load
lowering and holding the suspended load at rest. Bridge and trolley shall have
electrically operated fail -safe brakes. Brakes shall be sized for the full load torque
of the motor with a safety factor.
 Pulleys
Hoisting pulleys consist of a central hub with a bore for the shaft, a circular rim
with a deep circumferential groove for accommodation the hoisting rope and web
or individual spokes connecting the hub and the rim.
 TROLLEY DRIVES
Motorized trolleys should be powered by slip ring or squirrel cage motor.

Acceleration and deceleration shall be limited to a maximum of 1.0
foot/second/second by means of an inertia wheel to minimize load swing. Trolley
brakes shall be provided.
Motor shall be protected from overheating by thermal protectors imbedded in the
windings. Totally enclosed motor and fully enclosed gearing should be directly
connected to the rotating axle. Wheel-to-axle connection is made by means of a
tapered lock system without keyway.

26
project
For large size trolleys, individual CT drives are used.
 Hoist motor and braking system

Hoist motor shall develop sufficient power to lift the rated load at the specified
speed.
Motor shall be rated for the number of starts per hour expected in the application
and for duty cycle.
 Spreader beam rigging
Figure 18 spreader beam with sling
Figure 19 spreader beam

27
project
Spreader beams are used in rigging and loading for a variety of construction as
well as transportation, they are basically just a very rigid steel section with
multiple connection points to attach both the lifter (usually a crane) and the object
being lifted.
Two lifting lugs on the top of the beam attach to the legs of a chain sling or
synthetic sling at a particular angle designed to ensure pure compression. This
evenly distributes the weight of the load across the two slings, which then connect
to a crane, hoist, or other lifting machine. Two lugs on the bottom (one at each
end) connect to a sling or hook which are then connected to the load
Mechanisms
An overhead travelling crane comprises of

 Hoisting,
 Cross travel And
 Long travel mechanism.
 Hoisting
The hoist mechanism mounted in a cross travel crab or trolley supported by the
crane bridge. The hoisting mechanism consists of
A drum made from rolled steel with helical
groove on its outer surface for winding and
unwinding of the hoisting rope, welded end
flanges and shaft

28
project
End bearing housings and bearings for supporting the drum and the shaft Drive
consisting of electric motor, gear box, couplings,
brake and supporting structural frames
Figure 20 Hoisting assembly
 Limit switches to prevent over-travel of the hook block.

 Cross travel mechanism
Figure 21 Cross travel mechanism
The hoist mechanism is mounted on the trolley or crab which is a structural

rectangular frame with traveling wheels at all the four corners. The trolley or the
crab fixed to the top of the bridges, one rail on each bridge along its length. The
cross travel mechanism consists of electric motor, gear box, coupling and brake.
The output shaft of the gear box is coupled to the long shaft on which are
connected
to the cross travel wheels.
 Long travel mechanism
The whole trolley with the hoist and the cross travel mechanism travels on rails
mounted on another large rectangular structural frame consisting of two bridge

29
project
girders and two end carriages. Wheels are provided at the four corners of this
frame and the long travel consists of motor, gear box, coupling, brake and wheels.
A) Single Girder Cranes
Single girder cranes are most cost effective for capacities up to 10 tons and 60 ft.
spans. By utilizing box girder technology, EMH can also provide this version up to
15 tons and 120 ft. spans. Reduced wheel loads combined with very low headroom
standard hoists provide outstanding value.
Figure 22 Single girder cranes

The advantages of single girder traveling cranes are evident with load capacities up
to 10 tons and spans up to 120m.
B) Double Girder Cranes
Double Girder Bridge Cranes are most frequently applied in capacities over 10
tons and or spans of 60 ft. They can be utilized at any capacity where extremely
high hook lift is required because the hook can be pulled up between the girders.
Double Girder Bridge Cranes are also ideal where high speeds and heavy service
are required. They are also highly suitable where the crane needs to be fitted with
walkways, crane lights, cabs, magnet cable reels or other special equipment.

30
project
Figure 23 Double girder crane

The advantages of double girder traveling bridge cranes become particularly
evident with load capacities over 10 tons, or spans of over 50'.
ABBREVIATION
WT ........................................................................................................................................total weight
Mt ......................................................................... total mass to be lifted
g ....................................................................................................gravity
Wd .........................................................................................design load
F.S .................................................................................. factor of safety
D ................................................................................................ diameter
W ................................................................................weight of the rope
A ..................................................................................................... .area
σb .................................................................................. bending strength
wr ..................................................................... toatal weight of the rope
Er......................................................................................youngs moduls of the rope
D ...................................................................................... drum diameter
Wb ............................................................................ .equivalent bending
Wacc.................................................................... load due to acceleration
Wsrt ........................................................................... load due to starting
Weff ................................................................................... effective load
P....................................................................................................... pitch
h1.......................................................................................... grove height
r ................................................................................ radius of the grove
a ...........................................................................................acceleration
F....................................................................................................... force
Nout............................................................................... output revolution
H .................................................................................................... power
Nin ................................................................................. input revolution

31
project
G.R ................................................................................... gear reduction

I ................................................................................................ gear ratio
V ................................................................................................. velocity
Σ ..................................................................................................... stress
σsur ..................................................................................... surface stress
σmax ................................................................................ maximum stress
k…………………………………………………………………….……load factor
Np ............................................................................ revolution of pinion
Nw. ................................................................................................................................... Revolution of
A ...................................................................... Center to center distance
ψA ………………………………………………face width to center distance ratio
kc ..............................................................................................................................................Static load
kd ..................................................................................................................................... Dynamic load
m .................................................................................................. module
mn …………………………………………………………………...normal module
ms……………………………………………………………….....standard module
γ……………………………………………………………………...pressure angle
f .............................................................................................. face width
β…………………………………………………………face width to module ratio
Zp ........................................................................... no of teeth on pinion
Zw.................................................................................. no of .teeth on w
J .................................................................................... factor for pitting
Sb......................................................................................................bending strangth
kl ................................................................................. factor for bending
ka...................................................................................................appplication factor
kv…………………………………………………………………….dynamic factor
km…………………………………………………………….……machining factor
kR ............................................................................................................................ Reliability factor
Cl………………………………………………………………….contact life factor
Sc………………………………………………………………...…allowable stress
Wn ........................................................................................ normal load
Wt .................................................................................... tangential load
T ................................................................................................... torque
Dp......................................................................... diameter of the pinion
Me ................................................................................. .equivalent load
M...................................................................................................................moment
pCT......................................................................... power for cross travel
pLT .......................................................................... power for long travel
Pso…………………………………………………………..wheel material strength
c1, c2, c3 .......................................................... factors in design of wheels
32
project
dwc ..................................................................... diameter of cross travel

tw ................................................................................... thickness of web
tf .................................................................................thickness of flange
b ....................................................................................... width of girder
h ...................................................................................... height of girder
Ixx ....................................................... .moment of inertia in xx direction
σ min, .............................................................................. minimum stress
σ max ............................................................................... maximum stress
τ all ....................................................................... .allowable shear stress
y .............................................................................................. .deflection
W .................................................................................... distributed load
E……………………………………………………………………youngs modulus
f ye …………………………………………………………….design shear strength

33
project
4.1.1 Significance of EOT with spreader beam

It gains a dominant relevance in engineering workshops to move extremely heavy
or bulky loads through aisles or on the floor during daily operations with
safest,accurate,and short period of travelling time with the help of spreader beam
rigging mounted on it.
4.1.2 Problem statement
The problem that observe when you entering to the shops is mainly lack of suitable
rigging system to that of overhead crane found on both tatek transformer
manufacturing industry and saris power factor correction industry.And also lack of
the overhead crane itself in some shops of the industry where they need this system
highly.
So I decide to overcome this problem by designing mainly spreader beam rigging

mechanism and also the design of main components of the EOT crane.
4.2 Objectives
4.2.1 Main objective
The main objective of this project is to design mainly spreader beam rigging for
suitable manufacturing area and the EOT crane itself.
4.2.2 Specific objective

 Design a hoisting mechanism with spreader beam rigging instead of sling
rigging that the company uses now.
 Design main components of EOT crane like bridge,rope,cross travel
trolly,end carriage
4.3 Advantage of the project

 Avoid or eliminate crushing or damage the load.
 Having long life span of the transformer by protecting it from mechanical
failures occured when hoisting and transporting of transformer.
 Saving foreign currency by manufacturing the crane in our country.
 Having high production rate to the manufacturing by reducing time to
transport products.
 Inorder to move or transport products(transformer and compact substation
transformers) by only oprating the crane using radio with out the help of
labour.

34
project
4.5 Major parts of an EOT crane
4.8 Advantages of Using a Spreader Beam

Spreader beams convert lifting loads into compressive forces in the bar and tensile
forces in the slings. Because of this, spreader beams are highly efficient in their use
of material, so they’re typically smaller, lighter, and less expensive to design and
manufacture.
Because they use two lifting points instead of one singular lifting point, the weight
of the load is distributed evenly across the beam, which eliminates the stress on a
single lifting point. Spreader beams are ideal for lifting very wide or heavy-duty
loads.
Spreader beams also help to control the load and when rigged properly, can reduce
the chances of:
Load tipping, sliding, or bending
Crushing or damage to the load because you can control the sling angles
They can also be designed in fixed dimensions or can be engineered to allow for
incremental adjustment of the sling angle, and the length of the beam itself, for off-
center load adjustments.

35
project
CHAPTER FIVE
DESIGN OF COMPONENTS
5.1 Design of Rope

Given parameters
Load to be lifted (300KVA transformer have estimated) 1000 k.g weight
Weight of the hook block 80 k.g
No of fall=4
Calculating the total weight on the rope

W= Mt*g
=1080 * 9.81
= 10594.8 N.
The weight acting on individual ropes will be;
10594.8 = 2648.7 N
4
Selecting a suitable type of rope from standards.
6*37 Steel wire rope has been selected which is used for an extra flexible hoisting
rope used in steel mill ladles, hoisting, cranes, high speed elevators.
1) Calculating the design load by taking a factor of safety for wire ropes used
for overhead crane and gantry cranes.
F.S = 5
Therefore the design load (Wd ) will be:
Wd =F.S * W
= 5*2648.7
= 13243.5N
2) Determining the working diameter of the rope (d).

From standards and tables the tensile strength for 6*37 steel wire rope is ;
For 550 d2 …………………1900MPa.

36
project
Evaluating d;
d = 15.5 mm Say 16mm
3) Calculating wire diameter (dw) and area of wire rope (A)

From standard table
dw = 0.045d= 0.72mm
A = 0.38d2 = 97.28mm2
4) Determining various stresses that act on the rope.
a) Determining the weight of the rope.

From standard tables w= 0.037d2= 9.47 N/m
wr = w * total length of the rope
wr = 473.6 N.
Where the total length of the rope is

(No of falls * Lift height) + Allowance (4*10)+10 = 50m.
b) Calculating the bending stress

σb = Er * dw
D
From standard tables the recommended ratio of drum diameter to rope
diameter is From 18 – 27d
Taking 25*d
D = 400 mm
Substituting the values:
σb = 144 N/mm2
The equivalent bending load on the rope will be
Wb = σb * A
Wb = 14008.32 N
c) Assuming the acceleration of low speed hoisting to be 0.34 m/s2, then the
load due to the acceleration is
Wacc = WT + w * a
g
Substituting the values above
Wacc = 3688.4 N.
d) Load due to impact loads during starting due to the absence of slackness in ropes.
37
project
Wsrt =2 (W + w)
Wsrt = 212843.2 N.
6) The normal or effective working stress during uniform lifting or lowering will be
Weff = W +w + Wb
Weff = 120429.92 N
Actual factor of safety during normal working condition will be
Design load = 132435 = 1.02 < 5
Effective load 120429.92
Effective load on the rope during starting

=Wsrt + Wb
= 226851.52 N
The actual factor of safety during starting
F.Ssrt = 1.65 < 5
Effective load on the rope during acceleration of the load
= W + w + Wb + Wa
= 124118.32 N.
The actual safety factor during acceleration
F.Sacc = 1.12 < 5
Since the ratios obtained are < 5 the above assumptions and selections of the rope
are safe.

38
project
5.2 Design of cross travel wheels
Figure 24 Cross travel wheel

Taking the rim width, bs to be 40mmfrom standard rim table
To find the minimum diameter that will support the total load acting on each wheel
will be calculated by using the empirical formula
d min >=W eff /Pso*c1*c2*c3*(bs-2rs)
d min= 4013
56Kg/cm2*0.89*1.05*1* (4cm-2*0.5cm)
= 25.56cm
d min= 300mm
Table factor of for wheel diameter calculation
Tensile stress of Material Min-1 C2 Duty % Duty
material factor factor
(Kg/cm2)
45 0.77 50 0.94 <16 1.25
50…52 0.89 45 0.96 >16<25 1.16
60 1.00 40 0.97 25<40 1.00

39
project
70 1.16 35.5 1.00 >40<63 0.9

31.5 1.02 >63 0.8
28 1.03
25 1.04
5.3 Over all dimension of the trolley
Figure 25 Overall dimension of the trolley
Clearance C1=300mm C’1=100mm

C2=150mm C’2=50mm
C3=50mm C’3=100mm
Total length of the trolley = C1 +length of gear box of hoisting +C2 + Width gear
box for cross travel + C3
= 300+500+150+250+50 = 1250 say 1300mm
Total width of the trolley=2*C’1+C’2+length of the drum +C’3+ Width of the
hoisting gear box
=2*100+50+800+100+350 = 1500mm
Trolley wheel gauge =C’1+ length of the drum+C’3+width of the hoisting gear box
+ dWCT/2

40
project
Wheel center to center distance =width of cross travel gear box +C2+length of
hoisting gear box 2
= 1250 +150 + [500-40-105] + 120
= 750mm
5.4 Design of bridge girder

The main bridge Girders are fabricated from high quality steel plates forming a
rectangular box section. To achieve the desired stiffness diaphragms are fitted at
regular distance.
The girders are provided with the required camber so that the Girder deflection in
full load condition will remain well within its allowable limit of 1/900. Internal
surface of the box girder is free from corrosion as the box is welded and there is
not contact with outside atmosphere.
The heavy box type structural construction of Double Girder Crane ensures safety
and gives feeling of security to the worker while handling heavy loads and it also
reduces chances of damage in transit
h = 1000mm
b = 600mm
tf =10mm
tw =8mm
Calculating the second area moment of inertia

I =IG+AY2
In the x direction
 For area 1 and 2 (web plates)
Ixx1=bh3/12*2= [[1000-20]3*6]*2 = 1254.9*106mm4
12
 For area 3 and 4(flange plates)
Ixx2= bh3/12 +AY2 = [[600*103] + [600*10]*[500-4]2]*2 = 2940.4*106
12
Total Ixx =Ixx1+Ixx2 = 4195.3*106 mm4
In the z direction
41
project
 For web plates

IZZ1 =bh3/12 +AY2= [6*[1000-20]3 + 6[1000-20]*2502 *2
= 1607.5*106 mm4
 For flange plates
IZZ2 = bh3/12 = 0.1*106 mm4
Total IZZ = IZZ1+ IZZ2 = 1607.6 *106 mm4

42
project
Finding the bending moment due to dead weight

Calculating the dead weight of the girder
Flanges thickness ………10mm
Width………….500mm
Length………...2000mm
Volume = 0.008*0.5*20 =0.12m3
Web thickness………..8mm
Width…………. [1000-20] mm
Length………..2000mm
Volume = 0.008*[1000-20]*2000 = 0.16m3
Total volume =0.12*2 +0.16*2 =0.595m2
Density of mild steel (ρ) =7680 Kg/m3
Total mass of the girder = 0.595*7680=4569.6Kg and the weight became
44.83*103 N
Calculating the weight mass of the diaphragms
Thickness ……….. 6mm
Width……… [500-8] mm
Length…….. [1000-20] mm
Volume =0.0029m3 because the 40% of the volume is knock out the left volume=
0.0012m3 and in the girder there are 20 number of diaphragms Vtotal
=0.0012*20=0.024m3
The mass of the diaphragms =184.32 Kg and the weight =1808.18 N
Calculating the weight of the rib
Thickness…………..0.04mm
Width………………0.04mm
43
project
Length……………...2000mm
Volume =0.032m3
The mass of the rib =0.032* 7690=245.76 Kg and the weight =2410.9N
Therefore the total dead weight distributed on the length of the girder, ( W
)=2410.9N +1808.18 N+44.83*103 N =49049.08N/20m = 2452.45N/m
The bending moment will be
∑FY=0, RA+RB=2452.45N since RA and RB are at same distance from the center
RA=RB
RA=RB=1226.23N
∑FY=0, V1x +W*X –RA=0
V1x= W*X - RA =47822.85N
∑MA=0, M1x +W*X*X/2 –RA*X=0
M1x=RA*X – WX2/2
M1x= 1226.23 *10-2452.45*102/2
= 116.49*103Nm
Finding the bending stress of the girder
 σ = MZ/I
σ x = M max Z / Ixx where, Mmax = M max + M1x

= 368.4*10 Nm + 116.49*103Nm
3
= 484.89*103Nm
σ x = 57.75MPa
σ Z = Mmax X / IZZ
σZ = 75MPa
σ min, σ max = σ x + σ Z/2 + √( σx – σ Z)2 + τxz) 2
τ max = σ min + σ max = 66.5 MPa
44
project
2
σ min =54 MPa
σ max =79MPa
τ all = 210 Mpa
σ all = σ Y / F.s where the factor of safety = 2
σ all = 110MPa
Because σ max =79MPa < σ all = 110MPa the design of the bridge girder is safe

45
project
Calculation on deflection of the girders
Deflection of girders is one of the most important factors in the design of EOT
cranes. This is because stability is a major criterion for the dynamic activities
carried out during the operation of the crane. For mid range cranes having two
girders, the recommended value of the deflection should be less or equal to
1/1000th (<=20mm in this design case) of the length of the girder.
The loads that act upon the girders are; two wheel loads on each girder, self weight
(also called dead weight) of the girder, self weight of stiffeners1, weight of
railways for the wheels.
Determination of the self weight ….
Determination of stiffeners weight…
Since there are there different loads acting on a single girder, the principle of
superposition is imposed.
The deflections obtained are at midways of the girders.
Self weight
For simply supported beam with uniformly distributed load, the maximum
deflection is given as
 5wl 4
y(1) max 
384EI
 Where the negative sign indicates the direction of the deflection

-ve y direction.
 5 * 1351N / m * 20m
4
y (1) max 
384 * 200 * 109 pa * 4195.3 * 10 6 m 4
y(1) max  3.354 *103 m
a) Concentrated loads due to the wheels
1 Stiffeners will be explained later.

46
project
Since the position of where the maximum deflection is not known,

continuous iteration /deflections should be checked.
i) Taking load 1 to be at center.
By the principle of superposition, the effects of loads 1 and 2 will be finally added
with the deflection found in a.
The deflection equation that will apply for a simply supported beam with
concentrated load acting at the center will be,
 wl 3
y( 2) max atL / 2 
48EI
y(2) max atL / 2  8.99 *103 m
When load 1 is at the center, load 3 will be 750mm offset from the center because
the center to center distance between these two wheels is 750mm.
For a simply supported beam with a concentrated load acting eccentrically to the
center with a>b,
y(3) max atL / 2 


 wb L2  B 2
*

4 EI 43
y(3) max atL / 2  5.542*104 m
ytotal  y (1) max  y ( 2) max atL / 2  y (3) max atL / 2
ytotal  0.01289m  12.89mm
Since ytotal  12.89 < 20mm then the selection of the girder section dimension is
safe for deflection.
2nd position of the trolley
When the trolley is at the center of the girder i.e. when loads 1 and 3 are 350 mm
apart from the center of the girder.
On conducting similar procedures as in b;
ymax 2  12.946mm
Is less than 20mm and is safe.

47
project
5.5 Design of spreader beam rigging
Figure 26 spreader beam without load

Spreader Beams are a very versatile solution for multiple lifting requirements.
From 2 points of lift, to 4, to 6 or 8, as long as you have the head height available
(distance between the hook and the load) then a spreader beam system is a cost
effective and easily accessible lifting solution.
5.5.1 How spreader beam reduces horizontal forces?

Spreader beams reduce the risk of damage to the load with the ability to control of
the sling angles, spreader beams can protect a load from damage. Keeping the
angle from the pick points to the beam means there are no angular forces on the
load, ensuring no damage or pinching on the load. At the outset, it is important to
clarify the difference between a spreader and a lifting beam. A spreader beam is
designed to take primarily compressive loads, as can be seen in the figure above.
If we resolve the forces on the whole beam, we get the force diagram as above. We
can see that the vertical downward forces of Fv1 and Fv2 are balanced by the
components F1y and F2y, while F1x and F2x are the compressive forces on the
spreader. Some bending may be experienced as the forces F1x and F2x are acting
at the hole of the pad-eye, which is offset from the centerline of the spreader by
some distance. However, the primary load on the spreader is compressive stress.
There can be some lateral-torsional buckling too if it is an I-beam spreader.
Lifting beams, on the other hand, are designed to take bending loads. A simple
lifting beam is shown below:

48
project
We can see that it has a lifting eye at its top in the middle, while the eyes below are
used to connect the slings to the lifted object. If we resolve the forces, we can
immediately see that the lifting beam will be primarily under bending stress.
5.5.2 Loads on the Spreader Beam

Next, we analyze the loads which affect the spreader’s design.
Following are the loads which affect the spreader:
Sling
Hook
pad eye and d-shackle
Spreader beam
Sling
Distribution transformer
Figure 27 spreader beam with transformer
Lifted object weight and CoG – the lifted object’s weight is to be borne by the
spreader beam. Further, the location of the CoG of the lifted object has critical
effect on the sling loads. If the CoG is not located at mid-point of the cargo

49
project
(lengthwise, see Fig 1), then the loads on the slings will not be the same. The
sling which is closer to the CoG is expected to take more load
Rigging Weight – additionally, the rigging weight below the spreader is to be
added
Dynamic Amplification factor – depending on the environment of the lifting
(onshore or offshore), a Dynamic Amplification Factor is to be added to the load.
Sling Angles and Loads

The angles of the slings 1 & 2 (in figure 1) made with the vertical must be less than
45 degrees. It is to be noted that the center of gravity (COG) of the lifted object has
to be in line (on the same vertical) as the crane hook. The sling lengths are to be
accordingly adjusted. If not, the object will experience a tilt during lifting which is
not desirable.
The next step is to calculate the loads on the slings above the spreader, i.e., the line
using a simple mathematical formulation, the sling loads are determined. It is
expected that the lift point which is closer to the COG will take more load.
Sling angle
 Sling angle of sling 1 with the horizontal α=tan-1(XCOG/HS TOP)
α1=tan-1(0.75/0.6)
=51.34˚
α2 =tan-1((1.20-0.75)/0.6)
=36.87˚
Lifting point and sling loads
 Load at lifting point 1
W1=DHL*SKL*(Lx-XCOG)
W1=10.87N
 Load on sling 1
FS1=W1/cosα1
=15.38 N
 Load at lifting point 2
W2=DHL*SKL*(LX-XCOG)
W2=10.87N
 Load on sling 2
FS2=W2/Cosα2
FS2=15.38N
Stresses
The next step is the calculation of stresses. The spreader experiences the following
stresses:
50
project
 Compressive Stress – this is the governing stress of the spreader. This is

calculated by dividing the compressive force on the spreader by the section
area of the spreader. COMPRESSIVE STRESS ON THE SPREADER
 Allowable compressive stress
(𝑘𝑙/𝑟)2
1− ]𝐹𝑦
σc;allow= 𝑘𝑙
2𝐶𝑐!
5 3( 𝑟 ) 𝑘𝑙
+ −( )2/(8𝐶𝑐2)
3 8𝐶𝑐 𝑟
=134.04 Mpa
Where; Effective length factor for spreader ;k=1
Slenderness ratio for spreader; kl/r=81.47
Value of Cc;Cc=√(2π2E/Fy)=108.06
Compressive force on the spreader beam;
Pspreader=Fs1*sin α1
=10.87
Compressive stress on spreader beam;
σc;spreader=pspreader/Aspreader
=17.78
 The spreader beam is safe because σc;spreader ≤σc;allow

51
project
5.6 Design of End carriage
As mentioned in the literature review, end carriages are placed on both sides of the
ends of the bridge girders to support the whole trolley frame and the material to be
lifted where the wheels of the long travel are fixed to which enables the whole
crane to travel along the length of the workshop bay.
The material for end carriages is also the same as the girders and for this design
case and for most practical cranes it is Mild Steel.
Figure 28 Plan view of a section of a crane

The end carriages and the girders should be fixed together as tight as possible
because the whole structure relies on this fixture. The design and selection of this
fixture is sophisticated and needs lot of calculation. Most crane manufacturers use
tight fitting or reamer bolts which are fitted by hammering and to assure the
strength they use black bolts or idle bolts at intervals specified by the design.
5.6.1 Calculation of the loads that act upon the end carriages
The loads that act upon the end carriage
are;
o Self weight or dead weight of
the girder
o The weight to be lifted
o The weights of the whole trolley
frame, railway etc.

52
project
Since the maximum loads are loads 1 and 3, these two loads are considered for the
design.
Case I) When the trolley is on the extreme left end.
Fro
m
pre
vio
us calculations,
WL= 44.83*103 N
W1= 45.3*103 N
W3 = 27.5*103 N
Using singularity theorem,
V ( x)  89.9  x  0 45.3  x  1.175  0

 27.5  x  1.925  0 44.83  x  10  0
M ( x)  89.9  x 1 45.3  x  1.175 1
 27.5  x  1.925 1 44.83  x  10 1
 Fy  0
R1  R2  WL  W1  W 3
53
project
R1  R2  117.6 * 103 N
 M1  0
R2 L  WL * L / 2  W1 * a  W 3 * b
 R2  27.7 * 103 N and
R1  89.9 * 103 N
Case II when the trolley is on the extreme right side.
Bending moment diagram

54
project
Since the loads acting didn’t change, R1  R2  117.6 * 103 N will hold for this also.
Using singularity theorem;
V ( x)  28.03  x 0 44.83  x  10 0
 45.3  x  18.175 0 27.5  x  18.925 0
M ( x)  28.03  x 1 44.83  x  10 1
 45.3  x  18.175 1 27.5  x  18.925 1
M2  0
R * 20  W 20 * 20 / 2  W 1 * 1.825  W 3 * 1.075
1
R  28.03KN
1
R  89.57KN
2
The maximum of the above reaction forces is used to design the end carriages.
Therefore R1=R2=89.9KN
Say 90KN.
On Checking the reaction of girder 2 i.e. when the loads acting are W2 and W4, the
same principle applies and the results that are obtained are,
i) When the trolley is on the left extreme end,
R’1=82.16KN.
R’2=27.24KN.
ii) When the trolley is on the extreme right side,
R’1=27.28 KN and
R’2= 82.12 KN
Finally since the reaction forces when checked with loads 1 and 3 is greater than
the reactions obtained by forces 2 and 4,the maximum of the above two is taken.

55
project
Assumptions
The diameter of the long travel wheels is 500mm.
Self-weight of the end carriages when compared to the loads applied is neglected.
The end carriage is a simply supported beam.
 Fy  0
R R  2R
A B 2
R R  180KN
A B
M A  0
R * 3.2  R * 2.25  R * 0.95
B 2 2
 R B  R A  90KN
Calculation of the bending moment.
Taking section A-A

56
project
 Fy  0
R  V  90KN
A
M A  0
 M  85.5kNm
Taking section at the center,
 Fy  0
 V=0
 MBB = 90kNm
Checking the bending stress with the material property
M Y
x  max
Ixx
Since the end carriage’s cross section is the same as the girder, Ixx is the same
 Ixx=4195.3*106 mm4
 x  10.7 MPa
 y  14.3 MPa
The principal stress will be
  (   )2
 max 
x

y x y
2 2
 max  15Mpa << 110 Mpa Therefore the design for bending is safe
5.6.2 Conclusion and recommendation
Overhead cranes are one of the most important materials handling equipment used
in industrial workshops and factories. Regardless of their priceless importance,
most of our country’s factories and workshops are not using them. This is due to
lack of manufacturing firms and designing companies that manufacture EOT
cranes. Since this problem has to be solved by engineers, the importance of this
project has become undoubted.

57
project
Therefore in this project designing electric overhead cranes components that can
be manufactured are performed and the parts that need special manufacturing
process or components which are not familiar in our country has been selected
from the standard table and aimed to bought from manufacturers of the parts of
cranes from abroad.
In designing overhead cranes for our country’s standard and demand, it’s believed
that this design report will have a lot to contribute.
And also the spreader beam rigging mechanism that is new to the company is the
best way to solve the problems which we see in the previous lessons.

58
project
5.6.3 Reference
 Grundlagen der Fordertechhnik ,Prof.Dr.-Ing.Habil.G.Pajer, Prof.Dr.-Ing M
Scheffler , Prof.Dr.-Ing F.Kurth
 Schaum’s outline of theory and problems of strength of materials, William
A.Nash ,4th edition,McGraw-Hill
 A Text Book Of Machine Design , R.S KHURMI & J.K GUPTA ,Eurasia
Publishing House (Pvt.) Ltd. 2002, New Delhi
 Mechanics of materials 1, EJ. Hearn, 3rd edition,Mc Graw-Hill.
 Different web sites from internet(www.the naval arh.com,www.marine
hoisting.com)
Appendix

59
project

60
project

Dilla Unv Ethio-Engineering

Uploaded by

Copyright:

Available Formats

Dilla Unv Ethio-Engineering

Uploaded by

Document Information

Original Description:

Copyright

Available Formats

Share this document

Share or Embed Document

Sharing Options

Did you find this document useful?

Is this content inappropriate?

Copyright:

Available Formats

Dilla Unv Ethio-Engineering

Uploaded by

Copyright:

Available Formats

Design of spreader beam rigging Dilla university final

internship report and project

From February 2020 to December 2020

Name: Ephrem Milion

Submitted date: MARCH 03/2021 GC

Ephrem Milion __________________________

This report has been approved by my supervisor and mentor:

Supervisor name -Teketel T. Approved On Internship Project Proposal

BY EPHREM MILION 2021 GC

BY EPHREM MILION 2021 GC

BY EPHREM MILION 2021 GC

BY EPHREM MILION 2021 GC

BY EPHREM MILION 2021 GC

LIST OF TABLE OF FIGURE

BY EPHREM MILION 2021 GC

1.1 History of EEGPEMI

1.2 Main products

 Power factor corrector, compact Distribution sub-station and Motor

Figure 1 Low voltage switchgear

Transformer Factory (AA TATEK)

BY EPHREM MILION 2021 GC

TATEK Transformer production Factory produces different KVA rating power

1.3 Main customer of the factory

BY EPHREM MILION 2021 GC

1.4 Organization flow

Engineering Store production

Process Product Core

Figure 4 organization flow

BY EPHREM MILION 2021 GC

1.5 Work Flow

Figure 5 Work flow

BY EPHREM MILION 2021 GC

2.1 The way I get into the company

BY EPHREM MILION 2021 GC

Figure 6 bending machine

Figure 7 CNC TURRET punching machine

BY EPHREM MILION 2021 GC

Figure 8 shearing machine

BY EPHREM MILION 2021 GC

Figure 9 winding machine

BY EPHREM MILION 2021 GC

Transformer body production

BY EPHREM MILION 2021 GC

Figure 10 CNC plasma cutter

Figure 11 Drilling machine

BY EPHREM MILION 2021 GC

Figure 12 Rolling machine

BY EPHREM MILION 2021 GC

Figure 13 arc welding

BY EPHREM MILION 2021 GC

BY EPHREM MILION 2021 GC

Figure 14 lathe machine

2.3 flow of the sections

insulation Cutting stage

core and winding

Insertion of core and winding into

Figure 15 flow of the sections

BY EPHREM MILION 2021 GC

2.4 Work tasks you have been executing