UNION FENOSA gas

SEGAS Services
UCUF

Gas Turbine
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine

TRAINING PROGRAM - PHASE IIA

FOR
LNG PLANT at DAMIETTA

Gas Turbine
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine

Introduction
Turbine Development
The origins of turbines go back
to an Egyptian
scientist/philosopher called Hero
in about 250 BC
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine
Although the basic theory of
how gas turbines should
function was known long ago ,
detailed knowledge of flow
and materials that could
withstand high temperatures
was not available to make the
gas turbine a useful power
supply.
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine
The following is a summary of the main points in gas
turbine history:

• A basic turbine patent was issued to John Barber in 1791

• One of the first gas turbines that actually worked was built in France
by Stolze, around 1900
• The Brown Boveri Company did considerable pioneering of gas
turbines used for power generation and industrial applications. One of
their fIrst sizable gas turbine power plants was used in Switzerland in
the 1930s.
• The first turbojet-powered flight was in 1939 .
• In the 1940s and 1950s extensive work was being done, primarily on
aircraft, to make the gas turbine a viable source of power
• Since then the gas turbine has been refined into a very reliable,
versatile engine, with a high power-to-weight ratio
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine
The Gas Turbine Today
The gas turbine is an internal combustion, constant flow engine designed
to convert the energy of fuel into useful power. The fuel is burned to add
heat to a gas ( usually compressed air ) .
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine
Objective One
General Applications
The efficiencies and power outputs of earlier gas turbines were
limited by the fuels available and by the lack of metals that could
withstand high temperatures. Early air compressor and turbine
efficiency was not high enough to give a reasonable net output of
power. The low efficiency of the compressor and turbine meant that
almost all of the turbine output was used to drive the compressor.
Efficiency has now increased to produce a more useable engine.
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine
TODAY gas turbine engines are being used extensively for aircraft
propulsion and have recently made more inroads into industrial
applications
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine
They are used in high-speed marine propulsion by many navy ships. Gas
turbines are currently used for stationary power generation both as
standby and main power generation. There have also been many
experimental units built and operated in railroad service, cars and heavy
equipment.
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine

Gas turbines are in general or experimental use in

the following applications:

• Aircraft
• Power plants
• Standby equipment
• Boat and ship propulsion
• Gas pipeline compressor drives
• Railroad (have been used but are not common)
• Automotive (extensive experimentation in the past)
• Heavy mobile equipment (experimentation)
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine

Stationary Industrial Applications

The research and development of the gas turbine has had II1ost of
its emphasis in aircraft applications because of use in the military
and aviation industry. Aircraft gas turbines have shown great
reliability and were successfully tried in industrial installations.
Demand lead to more development of aircraft turbines adapted for
stationary applications. Many designs have now become
specialized to the needs of stationary plants. In industrial
applications, the combustion chambers can be separated from the
main engine body and the air and hot gas ducted from the
compressor to the combustion chamber and then back to the
turbine.
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine
These external combustion
chambers (Figure 6) allow the
use of a wider range of fuels. The
external chambers also make it
easier for the addition of
regeneration and cogeneration
equipment, although this
equipment is not limited to
turbines with these external
combustion chambers.
(Regeneration is the term used
when some of the exhaust heat
is used to heat the air of
combustion. Cogeneration is the
term used when exhaust heat is
used to generate steam for
power generation of other plant
processes.)
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine
Some gas turbines are coupled
directly to the machines they are to
drive. Some commonly driven
industrial units are gas pipeline
centrifugal compressors and electric
generators. In many cases the most
appropriate and efficient speed of
the gas turbine is not the same as
the speed desired for-the driven
machine. In these cases, speed
reducers or speed increasers are
used to achieve the appropriate
output shaft speeds. Gas
transmission pipelines use many high-ratio centrifugal compressors that have step-up
gearboxes of approximately 2: 1 ratio. Generators for electric power must run at speeds
that are multiples of 60 for the correct cycles in the power grid. Direct drives are only
possible if the turbine is closely matched to the application.
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine

Objective Two Basic Categories for Gas Turbines

Shaft Types Single Shaft
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine

Split Shaft
The split shaft turbine has two shafts. One shaft is connected to the
compressor and the gas generation turbine, anther shaft is attached to
the power turbine and the load or speed reducer. There are suitable for
variable speed operating conditions.
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine
Twin Spool Shaft
Twin spool shafts have one shaft running inside another. There are two
separate compressors and two separate turbines. The gas turbine engine
shown in has a twin spool gas generation section and split shaft type
power section.
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine
Gas Generation Section
The gas generation section of the gas turbine brings air in from the
compressor to mix with fuel in the combustion chamber to create hot
expanding gases that can be harnessed.
The main parts of this
section are:
-Compressor (s )
-Combustion Chamber (s )
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine

Regeneration
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine

Basic Turbine Principles

There are several laws of nature that apply to the operation of gas turbines. The
most important ones are Newton’s third law Bernoulli’s principle.
Newton’s Third Law
For every action there is an equal
and opposite reaction. The recoil
from firing a shotgun is a good
example of this law in action. As
the bullet leaves the barrel
( action) there is a force against
the hunter’s shoulder ( reaction ) .
When this is applied to a turbine,
the gas accelerates through the
reaction blading, pushing back on
the blades as it leaves.
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine
Bernoulli’s Principle
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine

Impulse
Blades
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine

Reaction Blades
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine
Gas Turbine
Blading ( Impulse
and Reaction
Blading )
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine
Nozzles ( Stationary Blades )
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine

Basic Turbine Operation

 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine
Comparison of Events in Gas Turbine and Piston Engines
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine

Objective Three
Gas Turbine Components

Air Filtering
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine

Air Intake
Compressors
The function of the
compressor is to provide
the turbine with
pressurized air for
combustion ( primary air )
and cooling ( secondary
air ) purposes.
There are two basic types
of air compressor
-Radial flow ( Centrifugal )
-Axial flow
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine
Radial Flow ( Centrifugal )
Compressor
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine
Axial Flow Compressor
As the name implies, the airflow through the axial flow compressor is
parallel to the shaft axis. There are two main components :
-Rotor with blades
-Stator with blades
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine

A typical Industrial Axial Flow Compressor

 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine

Axial Flow Compressor Rotor Blades

 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine
Combustion Chamber ( Combustor ) Parts and Operation
Most of the commonly used
combustors or combustion
chambers are designed with
several main parts and areas
so that combustion is
continuous and complete

The Parts of the

Combustor are
- The Combustion Chamber
housing ( Combustor ) is
the outside housing
-The Combustion Chamber Liner ( Flame Tubes ) is the inside of the housing
- The Fuel Nozzle ( Fuel Injector, Atomizer, or Vaporizer ) Injects the fuel
- The Igniter Ingnites the Fuel/Air Mixture
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine
Styles of Combustion Chambers ( Combustors )
Can Type
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine

Annular Type
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine

Can-Annular Type
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine
Turbine Power Assembly
The Turbine Assembly has two main Parts :
- Nozzles ( Stationary ), often called turbine nozzle vanes, turbine guide
vanes, nozzle diaphragms, or nozzle guide vanes
- Turbine Rotor ( Rotating
Turbine Wheels )
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine

Nozzles
The Nozzles are located
after the combustion
Chamber and Just
before the turbine
blades. Nozzles use
reaction-type blades
that are fastened in a
stationary diaphragm
that holds them in an
equally spaced circular
pattern .
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine
Nozzles are often made of high-strength steel to withstand the direct impact of hot
high-pressure ,high-velocity gases from the combustion chamber .
To increase the
endurance of the
nozzles, new alloys
,ceramic ,ceramic
coating and air-cooled
nozzle vanes are being
used .Some gas
turbines will use nozzle
vanes ( blades ) built
with many small holes
or slots on the leading
and trailing edges
where secondary air is
forced through them for
cooling
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine
Turbine Rotor
The rotor discs are welded or bolted to a low alloy stell shaft. The turbine exerts a
high torque load on the shaft which then exerts a high torque load on the
compressor. The blades on the rotor discs are attached and locked and locked
securely to the rotor with sufficient clearance to allow for thermal expansion
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine

Blade and Disc

Cooling
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine
This is done by pushing
air under a thermal
shield that protects the
shaft and part of the
disc, which keeps the
shaft from direct gas
exposure. The shield
directs the air to the
holes in the rotating
turbine blades
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine
This cooling can reduce blade
temperatures by as much as 300
°C ( 572 ° F ) . By cooling both
the turbine and nozzle blades,
higher combustion temperatures
are allowed which make for a
higher power, more efficient, and
longer lasting turbine engine.
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine

Seals
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine

Factors Affecting Maintenance and Overhaul

 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine

Engine
Wash
System
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine

Inlet and Exhaust

Ducting
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine
Gas Turbine Principles and Designs
Objective 1
GAS TURBINE ADVANTAGES
Modem gas turbines have a number of significant advantages over other
types of power plants, including:

• Capability to produce large amounts of power, currently up to 250 MW

• High power to weight ratio, making them especially suitable for applications
(such as offshore) where weight must be minimized
• Ability to use a wide range of liquid and gaseous fuels
• Ability to start rapidly, which is important for backup power generation
• Relatively simple and compact design with few and simple auxiliary systems
• High availability and reliability and ability to minimize outage time by quick
replacement of the gas turbine in case of major failure
• Remote operation capability with minimal operational manpower requirements
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine

DISADVANTAGES

• The turbine engine has a few drawbacks, which have prevented

its widespread use in automotive applications
• Turbine engines have high manufacturing costs - Because of
the complicated design, manufacturing is expensive
• A turbine engine changes speed slowly - A gas turbine is slow
to respond, relative to a reciprocating engine, to changes in
throttle request
• A gas turbine is less suitable for low-power applications - At
partial throttle conditions, the efficiency of the gas turbine
decreases
• A turbine requires intercoolers, regenerators and / or reheaters
to reach efficiencies comparable to current gasoline engines;
this adds significant cost and complexity to a turbine engine
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine

Types of Industrial Gas Turbines

There are tow basic types of industrial gas turbines : aero-derivative-derived from
the jet engines used in aircraft , and heavy- duty gas turbines- only designed for
land-based applications Each type has advantages and disadvantages, which
make them more suitable for certain applications .
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine
Heavy-duty gas turbines share many design aspects with steam turbines,
compressors and plant machinery. Because weight is less of an issue in
many applications, their layout is more flexible and their design is more
rugged than aero-derivatives.

In general, heavy-duty gas turbines are :

Larger and heavier than their aero-derivative equivalents

Very durable with long intervals between overhauls which makes them
especially suita1;Jle for base load applications
More efficient than aero-derivative engines of the same capacity
Able to use all fuels including distillates, residuals and crude oil
Able to accommodate a flexible layout between compressor, combustors
and turbine to allow for inter-cooling, regeneration, steam injection,
combined cycle, closed cycle and reheat
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine
An example is the gas turbine shown in Fig. 2. The identification of the
major components of the gas turbine unit, and in particular, that one of
those components is referred to specifically as the turbine. The term "gas
turbine" is commonly applied to the entire collection of components,
including the turbine section. However, when the term "turbine" is used
on its own, this refers only to the specific turbine section of the gas
turbine.
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine
Industrial Applications of Gas Turbines
Industrial gas turbines are used for a very wide range of applications, for both
electric power generation and to drive equipment such as pumps and
compressors.
Gas Turbine Major
Components
While gas turbines exist in
many different designs, every
gas turbine has three major
components, which are shown
in Fig. 3

-Compressor section
-Combustion section, also
called a combustor
-Turbine section
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine

Simple Gas Turbine Operating Principles

 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine
Objective 2
In the single shaft arrangements shown in Fig. 5, the compressor, turbine
and load are all connected and rotate at the same speed. The more
common situation is for the load to be connected to the turbine, as shown
in Fig. 5(a) and Fig.6 Another arrangement, as shown in Fig. 5 (b) is for the
load to be connected to the compressor.

Contd.
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine
Objective 2
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine

Dual Shaft
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine
Open Cycle
Operation
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine
Closed Cycle Operation
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine
Gas Turbine
Installation
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine

Objective 4
EFFICIENCY AND RATING OF GAS TURBINES

Gas turbines are normally rated in terms of the power produced at the
output shaft where it connects to the generator or compressor. The power
rating specified by the manufacturer will be in kilowatts, at a standard of
15°C and at sea level, using natural gas as a fuel, air with 60% humidity
and with no intake or exhaust losses.
Thermal efficiency is the ratio in % of the rated power and the fuel energy
rate. The fuel energy rate is calculated by multiplying the fuel flow rate by
the lower heating value of the fuel. Modem gas turbines are able to reach
efficiencies of 35% to 40% in simple cycle mode without the cycle
improvements or combined cycle described below.
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine
Cycle Improvements

Regeneration
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine
Combined Cycle
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine

Objective 5
COMPRESSOR DESIGNS

A highly efficient and capable compressor is critical for the efficient

operation of a gas turbine. Two types of compressors are used in gas
turbines:
.Centrifugal or radial Axial
.In small gas turbines, centrifugal compressors are often used, in
combination with several axial stages. The majority of large gas turbines
use a multi-stage axial compressor. Since the compressor absorbs up to
7j of the energy provided by the fuel, it must be structurally sound, as well
as efficient.
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine
CENTRIFUGAL
(RADIAL)
COMPRESSORS
These compressors take air in
at the centre or "eye" of the
rotor. Due to the high
rotational speeds of the rotor,
the air is accelerated by the
blades and forced radially to
the edge of the rotor at high
velocity by centrifugal force.
There, the air is received by
the diffuser, which in turn,
convens the high velocity to
pressure energy. The
components of a centrifugal
( Contd. )
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine
compressor rotor are shown1'n Fig;13. A multistage centrifugal compressor
design is shown in Fig. 14. Advantages of the radial or centrifugal compressor are
simplicity, strength and short length.
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine
Axial Compressors
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine

Objective 6
Combustors

Contd.
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine

Can-Annular
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine

Annular
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine

Objective 7
Turbine Materials
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine

Objective 8
Control Systems
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine

Objective 9
Operating
Parameters
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine

Gas Turbine Auxiliaries and Operation

Objective 1
Bearings
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine

Radial Tilt-Pad
Bearing
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine

Tilt-Pad Thrust
Bearing ( Solar
Turbines )
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine
Aero-Derivative
Gas Turbine
Lube Oil
System
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine

Heavy- Duty
Gas Turbine
Lube Oil
System
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine
Objective 2 Fuel Gas System
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine

Fuel Gas Metering

Valve (General
Electric )
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine

Monitoring
Screen for the
Fuel Gas
Control System
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine
Fuel Oil System
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine

Dual Fuel Systems

 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine

Objective 4
NOx Emissions
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine
Dry Low NOx
Combustion
System
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine

Objective 5
Pneumatic Starters
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine
1. Clutch Lubrication
Fixed Orifice
2. Gas Shutoff Pilot
Solenoid Valve
3. Pneumatic Starter
Motor
4. Gas Shutoff Valve
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine

Electric Starters
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine

Electric Starters
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine

Objective 6
Air Intake
System
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine

Anti- Icing
Systems
The formation of ice the air
intake or on the first few
stages of the compressor
can occur if a combination of
temperature and humidity
takes place . If chunks of ice
are ingested into the
compressor, major damage
can result including
catastrophic destruction of
the compressor section
blading
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine
Anti-icing systems
may operate by :
- Bleeding air from the
compressor and
injecting it into the front
of the compressor
through the nose cone
and the first few stator
vanes
- Installing heating coils in
the air intake
- Feeding heating air from
some other source such
as the exhaust into the
air intake
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine
Exhaust System
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine

Objective 7
Gas Turbine Start-Up
Procedure
The basic steps in starting a gas turbine are :
-Preparation for startup
-Start initiation
-Crank and lightoff
-Warmup
-Loading
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine
These steps must occur
in a specific sequence
and at certain time
intervals. They are
usually managed by the
control system and the
operator often has no
role except to watch the
process. If certain
conditions occur or
specific requirements are
not met at some point in
the startup sequence, the
startup will be aborted
and the unit stopped. The
progress of the startup is
displayed on a control
panel such as the one
shown in Fig. 22.
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine

Crank and Light off

 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine

Objective 9
Off- Line-
Waterwash
 UNION FENOSA gas
SEGAS Services
UCUF

Gas Turbine

Waterwash Cart