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Slide 1
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Slide 2
Model Number Designation
Since April of 1983 all LM2500
engines have been identified by
a numbering system consisting
of a prefix, engine family
designation, type code, and
configuration code. Engines
manufactured before April 1983retain the old numbering system
and it is not anticipated that
they will be updated with the
new model numbers.
Example: 7LM2500-PE-MGW
7LM = Prefix
2500 = Engine family
designation
PE = Type code
MGW = Configuration code
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Slide 3
The prefix 7LM is a GEcompany designation for amechanical, aero derivative(non-aircraft) gas turbine or gasgenerator. The 7 is thedepartment number for theMarine & Industrial section ofthe GE Aircraft EngineCompany, L stands for landand M for Marine.
The Engine family designationis determined by taking thenominal brake horsepowerrating and dividing it by 10. TheLM2500 had an initial designrating of 25,000 bhp, dividingthis by 10 gives an engine
family designation of 2500.
The type code is alwayscomprised of two letters. If the
first letter is a G it would
mean that the engine is a gas
generatoronly, it was not
intended to be coupled to a GE
power turbine. The above
example indicates that the unit
is a gas turbine, by virtue of
the P. The second letter in
the type code indicates the
design differences of the unit.
Energy Learning Centerg
Slide 4
In the case of the LM2500+ the
second letter represents a
major design difference of the
same product. The letter K
would indicate a Single Annual
Combustor (SAC) engine. The
letter R would refer to a Dry
Low Emission (DLE) engine.
For a LM2500+ gas generator
engine built for a High Speed
Power Turbine (HSPT) the type
code would be GV for a SAC
engine and GY for a DLE
engine.
The configuration codeidentifies major physicalcharacteristics of the engine interms of utilization. Codes areassigned as follows:
HPT Blade Coatings
M = Marinized(CODEP orPlatinum Aluminide)
N = Non-Marinized
Fuel System
G = Natural Gas
L = Liquid Fuel
D = Dual Fuel (both types)
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Slide 5
NOx Suppression
A = Steam NOx with steam
power enhancementB = Water NOx with steam
power enhancement
C = Steam power
enhancement only
D = Dry low Emission
S = Steam NOx only
W = Water NOx only
X = NOx Suppressed with
water or steam (old
convention)
Accessories are considered tobe bolt on components whichcould be added or deleted fromthe engine anytime. Because ofthis they are not included in themodel designation of theengine. Accessories areidentified by kit identificationnumbers given on model lists orpurchase documents.
The following table illustratesthe difference between thevarious gas turbine modeldesignations and provides acorrelation between the old andnew numbering systems.
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Slide 6
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Slide 7
A Brief History
The LM2500 is an aero-
derivative gas turbine. At GEthis means that the basic design
has proven itself successful
initially as an aircraft engine,
with possibly several years and
and the experience of in-the-
field production engines to draw
from. The LM2500 is the most
successful aero-derivative in its
field. But, it was not the first, or
even in the first generation.
1959
The GE aero-derivative engine
makes its debut when provenaircraft engine designs are
adapted for use in two
experimental hydrofoils. A wide
variety of applications in marine,
industrial, electric utility and
other fields soon follow. The
following are the pioneering
derivatives and their uses.
Energy Learning Centerg
Slide 8
LM100
Derivation:
T58 Helicopter Turboshaft
engine
Applications:
V 169 Locomotive
HS Denison, Hydrofoil
HS Victoria, HydrofoilUSS President Van Buren
Hamilton Class USCG Cutter
100 ton ore hauling trucks
Bell SK 5 Air Cushion Vehicle
LM1500
Derivation:
J79 Airplane Turbojet
engine
Applications:
Portable aircraft catapult
USS Plainview, Hydrofoil
HS Denison, HydrofoilPG84 Class Gunboat
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Slide 9
1961
With the support of the U.S.
Navy, a long range programwas initiated to solve the
specific problems encountered
with operating in a marine
environment. This marinization
program included the
laboratory development and
testing of new materials,
protective coatings and control
devices that would operate
properly at sea. Through-out the
1960s this technology wasproven at sea and in industry.
1965
The U.S. Air Force awarded
General Electric a contract todevelop an engine for their new
super sized air transport, the
Lockheed C-5 Galaxy. This
engine, designated the TF39,
proved so successful that a
commercial version called the
CF6-6 was developed almost
immediately.
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Slide 10
1968
The basic design of the TF39(now in its second generation)was used in conjunction withthe marinization program tocreate the LM2500.
1969
The first production LM2500engine replaced one of twodevelopment engines installedaboard the GTS Adm. WilliamW. Callahan, a roll on/roll off(Ro-Ro) cargo ship with a GWTof 24,000 tons, and a cruisingspeed of 26 knots.
1971
The first engines were deliveredto industrial systems suppliersDresser-Rand and CooperEnergy Systems for natural gascompression applications.
Dresser-Rand
Columbia Gulf TransmissionCo., Delhi, Louisiana, USA
Great Lakes Transmission Co.,
Wakefield, Michigan, USA
Nova, Airdaire S/S, Canada
Nova, Clearwater, Canada
Westcoast Energy, Inc.,McLeod Lake, VBC, Canada
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Slide 13
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Slide 14
Genealogy
Derived from Proven Technology
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Slide 15
Gas Turbine Modules
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Slide 16
GLOSSARY
A
ABS - Absolute
ac - alternating current
ACCEL - Acceleration
Ac-dc - alternating current to
direct current
ACT - ActuatorAGB - Accessory Gearbox
ALF - Aft Looking forward
amp - amplifier, ampere, or
amperage
AOA - Angle of Attack
AR - As Required
Assy - Assembly
Ave - Avenue
@ - at
Alarms - predeterminedparametric values atwhich an automaticwarning is executed
B
Butt - Flanges that lie flatagainst each other
B/E - Base/Enclosure
bhp - brake horsepower
BSI - Borescope Inspection
Btu - British thermal unit
Blade - Rotating airfoil
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C
C - Degrees Centigrade
(Celsius)cc - cubic centimeter
CCW - Counterclockwise
CDP - Compressor
Discharge Pressure
CFF - Compressor Front
Frame
Chan - Channel
Check - Inspection off
CIP - Compressor Inlet
(PT2) Total Pressure
CIT (T2) - Compressor Inlet
Temperature
cm - centimeter CMD - Command
Co - Company
CO2 - Carbon Dioxide
Cont - Continued
Corp - Corporation
CRF - Compressor Rear
Frame
CW - Clockwise
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Slide 18
D
dc - direct current
distal - viewing lens in line
lens with object to be
viewed
DOD - Domestic Object
Damage
DLE - Dry Low Emissions
DVM - Digital Voltmeter
dwg - drawing
E
EEA - Electronic Enclosure
Assembly
F
F - Degree Fahrenheit
fig - figure
FIR - Full Indicated Runout
flex - flexible
FMP - Fuel ManifoldPressure
FOD - Foreign ObjectDamage. Thatdamage which occursto gas turbine internal
airflow pathsurfaces
Frame - Establishes therotational axis (housesbearing sumps)
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Ft - foot (0.3048 meter) or
feet
FWD - Forward
G
gal - gallon (3.785 liters)
GE - General Electric
Company
GG - Gas Generator
gpm - gallons per minute
Green - Repair weld on a weld
(previously) fully heat
treated part, not subjected
to heat treatment beforewelding. (No re- quirement for
solutioning,
re-solutioning, stress- reliving, or
aging of repair weld.)GT - Gas Turbine
H
Hg - Mercury
H2O - Water
HPT - High Pressure Turbine
hr - hour
HSCS - High Speed Coupling
Shaft
Hz - Hertz (cycles per
second)HPTN - High Pressure Turbine
Nozzle (vanes)
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Slide 20
I
id - inside diameter
IGB - inlet Gearbox
IGV - Inlet Guide Vane
in - inch
insp - inspection
I/O - Input/Output
IP - Idle PositionK
kg - kilogram
kg cm - kilogram centimeter
kg m - kilogram meter
kg/sq cm - kilogram per square
centimeter
kPa - kilopascal
kw - kilowatt
L
L or l - Liter
lb - pound
Lb ft - pound foot
Lb in - pound inch
LH - Left HandLS & CA- Lube Storage and
Conditioning Assembly
LSP - Lube Supply Pressure
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M
m - meter
ma - milliampere
max - maximum
MCU - Manual Control Unit
MFC - Main Fuel Control
Mfg - Manufacturer
mils - 0.001 inc
min - minimum or minute
ml - milliliter
mm - millimeter
mv - millivoltMw, - Mega watt MW or Meg
N
NGG (N1) - Gas Generator Speed
No. - Number
Nom - Nominal
Nozzle - Turbine Stators
NPT (N2) Power Turbine Speed
O
OAT - Outside Air Temperature
OD - Outside Diameter
OGV - Outlet Guide Vane
OS - Overspeed
OT - Overtorque
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Slide 22
P
para - paragraph
PLA - Power Lever Angle
PN(s) - Part Number(s)
pot - potentiometer
pph - pounds per hour
PPM - Parts per Million
press - pressurepsi - pounds per square inch
pressure
psia - pounds per square inch
absolute pressure
Psid - pounds per square (P)
inch differential pressure
psig - pounds per square inch
gage pressure
PS3 - Compressor Discharge
Pressure, Static
PT - Power Turbine
PT2 -Compressor Inlet (CIP)Total Pressure
PT5.4, - Power Turbine Inlet
PT4.8 Total Pressure
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Q
QAD - Quick AccessoryDisconnect
Qt - quart
Qty - quantity
R
Rabbet - Overlapping flange orjoint
Ref - Reference
Req - Required
Rpm - revolutions per minute
Reqd - Required
RTD - Resistance Temperature
DetectorRun on - The torque required to
Torque bring a fastener toa sealed position
S
SC - Signal Conditioner
SCP - Ships Control Panelsec - second
SFC - Specific Fuel
Consumption (lbs/bhp-hr)
SG - Specific Gravity
SIG - Signal
SN - Serial Number
SST - Signal Shank Turbine
Blade
Stall - A disruption of the
normally smooth airflowthrough the gas turbine
Energy Learning Centerg
Slide 24
Std Day- Standard Day 59 deg
29.92hg,0%hum,Sea
level
Stator - Casing which Case
houses internal
located vanes
Station - Location of a point on an
imaginary line through aturbine engine from front to
rear identifying
specific parts or sections in
Arabic numerals
Sys - System
T
Tabs - small protrusions
(for attachment or
alignment)
Tach - tachometer
Tangs - alignment tabs (fit into
slots or sockets)
TBD - to be determined
T/C - Thermocouple
Temp - Temperature
TGB - Transfer Gearbox
TM - Torque Motor
TMF - Turbine Mid Frame
TNH - High Speed Turbine
Speed
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Slide 25
TNL - Low Speed Turbine
Speed
TST - Twin Shank TurbineBlade
T2 - Compressor Inlet (CIT)
Temperature
T5.4,4.8- Power Turbine Inlet
T54,48 Temperature
U
US - United States
USA - United States of
America
VV - Volt
VA - Voltamps
Vac -volts, alternating
current
Vane - stationary airfoilsVdc - volts, direct current
VSV - Variable Stator Vane
W
W - Watt
WP - Work Package
X
X - By
X DCR- Transducer
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Slide 26
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All references to location or
position on the LM2500 are based
on the assumption that theindividual is standing behind the
engine and looking forward. This is
true in all cases unless stated
otherwise.
Unless otherwise stated, all views
in this training manual are from the
left side of the engine, with the
intake on the observers left and the
exhaust on the right.
All GE engines rotate CW aft
looking forward, (ALF) Generatorsare viewed forward looking aft.
(FLA)
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Slide 28
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Slide 29
Rubber Gasket
Keep Clean Room Clean!
P=P0 vs. P1
1H20=Alarm
2H20=S/D
Inlet has minimum of 200 lbs/sec airflow
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Slide 30
Inlet Components
The inlet components direct air into
the inlet of the gas generator to
provide for smooth, non-turbulent
airflow into the compressor.
These components consist of:
1. Inlet duct
2. Centerbody.
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Slide 31
Inlet Duct
The inlet duct is constructed of
aluminum (AMS4026) and shapedlike a bellmouth. The inlet duct is
painted white, and must be
maintained in the painted condition.
Centerbody
The centerbody is a flow divider
bolted to the front of the gas
generator. The centerbody is
sometimes known as the
bulletnose, and is made of a
graphite reinforced fiberglasscomposite.
unpainted
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Slide 32
Airflows
Introduction
Primary and secondary airflowsare supplied to the gas turbinethrough the inlet.
Primary air is supplied to theenclosure inlet plenum area, andflows through the gas turbine.Secondary air is supplied to the
enclosure gas turbineenvironment, and provides acooling flow around the gasturbine.
Most primary air within the engineis used to support the gas turbinepower cycle (inlet, compression,ignition,
expansion and exhaust). This
airflow is referred to as the main
gas flow, and its flow path is the
Main Gas Path.
Some of the primary air is
extracted from the main gas path
at the 9th and 13th stages of
compression, and from the
compressor discharge chamber tosupply various cooling and
pressurization functions essential
to the operation of the engine.
This reduces the total amount of
air available to the power cycle,
and for this reason, these are
referred to as parasitic airflows.
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Slide 33
Customer bleed air requirements
for off-engine functions, are also
supplied by parasitic airflow fromthe compressor discharge
chamber.
Main Gas Path
Between the gas turbine inlet and
the compressor discharge, the
airflow duct formed by the inlet
components, CFF, and
compressor is continuously
convergent.
To produce airflow between these
two points, work is done on the airby the rotating compressor blades.
From the compressor discharge
chamber; through the combustor,
HPT, TMF, LPT, TRF, and gasturbine exhaust the airflow duct is
almost continuously diffusive.
Airflow between these two points
is produced by the internal energy
stored in the air during its
transition through the compressor,
and by energy added to the air by
combustion.
During its transition through the
compressor, ambient pressure
present at the gas turbine inlet isincreased by an 23:1 ratio.
Energy Learning Centerg
Slide 34
At the compressor discharge, the
combustor diffuser cowl forms an
airflow divider that routes
approximately 20% of the high
pressure air into the combustor
dome area. The remaining 80%
continues to diffuse into the
compressor discharge chamber
around the combustor.
As the 20% flow supplied to the
combustor dome area passes
through the swirler cups, it is mixed
with fuel, and ignites upon
reaching the combustion chamber.
The resulting combustion reaction
releases tremendous amounts of
heat, and causes violent and rapid
expansion of the ignited gases.
Large masses of high pressure
dilution air entering the
combustion chamber through
holes in the inner and outer liners
center the ignition flame within thechamber, and create an instant
cooling effect as they are
expanded by the super heated
combustion gases.
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Slide 35
Small film cooling holes drilled in
the leading edge of the inner and
outer liner rolled ring segmentsprovide a thin layer of cool
compressor discharge air between
liners and the hot combustion
gases (SAC only).
The constant inflow of high
pressure air through ignition,
dilution, and film cooling channels
forces the hot combustion gases
to expand aft-ward through the
turbines.
Most of the energy contained inthe expanding combustion
gases is dissipated against the
HPT rotor blades to drive the
compressor.The expanding gases discharged
from the HPT still contain
considerable amounts of energy,
and continue to expand through
the LPT.
After passing through the LPT all
usable energy is consumed, and
the depleted gases are expelled
from the engine through the
exhaust components.
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Slide 36
MAIN GAS PATH
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Slide 37
Aerodynamic Stations
Various instrumentation points
along the main gas path areidentified with aerodynamic
station numbers for monitoring
temperature and pressure
characteristics of the main gas
flow.
The system used to identify these
instrumentation points is mainly
intended for use by various
engineering functions in the
design phase and production
testing of the engine. However,some of terminology has spread
into the field.
Actual aerodynamic station
numbers range from 0 to 9, but
only military aircraft applicationsrequire this many numbers to
describe the main gas path.
LM2500+ applications require
only three numbers.
Station 2 (Compressor inlet)
Station 3 (Compressor
Discharge)
Station 5.4 (4.8) (Power
Turbine Inlet)
Combining the monitored
parameters with the station
numbers produces the
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Slide 38
Following terminology.
T2 (Compressor Inlet
Temperature or CIT)
Pt2 (Compressor Inlet
Total Pressure or CDP)
Ps3 (Compressor
Discharge Static
Pressure of CDP)
T3 Compressor DischargeTemperature
T5.4 (4.8) (Power Turbine
Inlet Temperature)
Pt5.4 (4.8) (Power Turbine
Inlet Total Pressure)
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Slide 39
Component Heritage
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Slide 40
Comparison
Maximizes Design Commonality with
Technology Advancements
=13.8 longer
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Slide 41
Frames
The LM2500 has 4 frames:
1. Compressor Front Frame (CFF)
2. Compressor Rear Frame (CRF)
3. Turbine Mid Frame (TMF)
4. Turbine Rear Frame (TRF)
Frames are rigid, non-moving,
engine structural elements. The
primary purpose of a frame is to
provide support.
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Slide 42
Each of these frames is an
assembly consisting of a central
hub connected to an outer casing
through the use of hollow struts.
These struts provide access for
cooling, lubrication, and
pressurization.
Compressor Front Frame
The CFF supports the forwardstub shaft of the compressor rotor
through the use of a roller
bearing, which is situated in the
hub of the frame, the walls of
which form the A bearing sump.
The CFF also supports the
forward
portion of the compressor stator,
inlet duct, centerbody, and the
front of the gas turbine.
The outer portion of the frame is
supported by 5 equally spaced
struts that radiate axially from the
hub. The struts are hollow to
provide services to and from the
engine, and are shaped likeairfoils to provide a turbulent free
airflow path for compressor inlet
air.
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Slide 43
#3 oil supply
#3R Bearing
A
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Slide 44
Compressor Section
The compressor is a 17 stage,
high pressure ratio, axial flow
design.
Air, taken in through the
compressor front frame, is forced
by rotating airfoils called blades to
pass into a successively smaller
volume. Passing through the 17th
and final stage results in a
compression ratio of
approximately 23:1.
The primary purpose of the
compressor is to provide high
volumes of compressed air to
support combustion; however
some air is extracted for cooling
purposes and customer use.
The major components of the
compressor are:
1. Compressor Front Frame (CFF)
2. Compressor Rotor
3. Compressor Stator
4. Compressor Rear Frame (CRF)
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Slide 45
Complete rotor weighs 1609 lbs
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Slide 46
Compressor Rotor
The HPCR is a spool/disk
structure. It is supported at the
forward end by the No. 3 roller
bearing, which is housed in the
CFF (A-sump). The aft end of the
rotor is supported by the No. 4 ball
and roller bearings, which are
housed in the CRF (B-sump).There are six major structural
elements and five bolted joints as
follows:
-Stage 0 blisk with wide chord,
shroudless blade
-Stage 1 disk
-Stage 2 disk with airduct
interface
-Stages 3-9 spool
-Stages 10-13 spool withintegral aft shaft
-Overhung stages 14-16spool
All rotor joints are bolted andinterfering rabbets are used in allflange joints for good positioningof parts and rotor stability.
A slip fit, single wall designed airduct that is supported by theshafts and a stage 2 disk, routespressurization air aft through thecenter of the rotor forpressurization of the B-sumpseals.
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Slide 47
Use of spools reduces thenumber of joints and makes itpossible for several stages ofblades to be carried on a singlepiece of rotor structure.
Stages 1 and 2 disks have aseries of single blade axialdovetails, while each of stages 3through 16 have onecircumferential dovetail groove inwhich blades are retained.
DisksDisks are major structuralelements providing strength and
rigidity to the assembly-andcontain only a single stage ofblades.
Spools
Spools span the distance between
disks, or are suspended from disks.A spool will contain more than 1
stage of blades and allows for
weight and material reduction.
Blades
Blades are airfoils retained by axial
dovetail grooves in stages 1 and 2,
and by circumferential dovetail
grooves-in stages 3 through 16.
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Slide 48
Blisk
Blade disk combination comes as
one unit. The blades are not
removable.
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Slide 49
Muff spline
Stage 0 blisk
Stage 1 retainers
Stage 2 retainers
1 stage of Compression= 1 stage of rotation & 1 stage of stator
#3R bearing
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Slide 50
HP Compressor
(midspan deleted)
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Slide 52
Circumferential Dovetail Slot Blade Retention
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Slide 53
Zero Indexing of HPC Rotor and HPT RotorForward Looking Aft
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Slide 54
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Slide 57
Stationary Vanes
Bleed air is extracted from the 9th and
13th stages through cut-outs in the
base of the vanes
-shows seal leakage
Safetied to preset lengthCross bleed orifice
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Slide 58
Variable Vanes
The Inlet Guide Vanes (IGVs) and
next 7 stages of vanes are called
Variable Stator Vanes, or VSVs.
These vanes are all mechanically
ganged together, and will change
their angular pitch in response to a
change in compressor inlet
temperature or a change in gasgenerator speed. The purpose of
this is to provide stall-free
operation of the compressor
through-out a wide range of speed
and inlet temperatures.
Due to their long length the IGVs
and stages 0, 1and 2 are
shrouded. The shrouds are
aluminum extrusions split into a
matched set of forward and aft
halves.
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Slide 59
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Slide 60
Variable Stator Control System
The variable stator vane (VSV)
control is an electrohydraulic
system consisting of an engine-
mounted hydraulic pump,
servovalve, and VSV actuators with
integral linear-variable differential
transformer (LVDT) to provide
feedback position signals to themain engine control. The system
positions the IGVs and first seven
stages of stator vanes (Stages 0
through 6) as a function of
compressor inlet temperature and
gas generator speed to maintain
optimal compressor
performance over the full range of
operating conditions.
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Slide 61
LVDT
Rod End
Drain Line
Head End
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Slide 62
BLEED AIR SYSTEM
Stage 16 compressor discharge
pressure (CDP), bleed air is used
for control of flame temperature in
DLE applications. Air is also bled
from stage 9 of the compressor for
sump pressurization and TMF
cooling. Stage 13 compressor bleed
air cools the turbine nozzles andused for LPT piston thrust balance.
COMPRESSOR DISCHARGE
PRESSURE BLEED
The CDP bleed manifold combines
two compressor case bleed ports
into a single interface. The
purchaser is required to provide the
interconnecting piping between this
interface and the package installed
CDP bleed valve (DLE only).
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Slide 63
STAGE 9 BLEED AIR
Stage 9 bleed air is extracted
though holes bored in the statorcasing aft of the stage 9 vane
dovetails. A manifold combines the
two HPC case ports into a single
interface.
STAGE 13 BLEED AIR
Stage 13 air is bled from the
compressor through holes in the
casing into a manifold and is used
to cool the turbine nozzles.
HIGH PRESSURE RECOUP
SYSTEM
The CRF B-sump pressurizationsystem is isolated from the HPC by
the CDP and vent labyrinth seals.
These seals serve to form HP
recoup chamber. The HP recoup
airflow results from compressor
discharge air leaking across the
CDP seal.
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Slide 64
Gas Generator Strut
Functions
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Slide 65Gas Generator Piping Left Side View
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Slide 66Gas Generator Piping Right Side View
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COMPRESSOR REAR FRAME
The compressor rear frame (CRF)
is an assembly constructed of aninconel alloy.
The CRF outer case supports the
compressor rear case, combustor,
fuel manifold, 30 fuel nozzles, 2 or
1 spark igniters and the stage 2
high pressure turbine nozzles.
Bearing axial and radial loads, and
a portion of the 1st stage high
pressure turbine nozzle load are
taken in the hub and transferred to
the CRF outer case through 10axially mounted struts.
The hub inner wall forms the B
sump area, and houses the #4
roller bearing (4R) and the #4 ballbearing (4B) or the #4 thrust
bearing.
There are 8 borescope ports
located in the CRF. Six (6) of
these ports are positioned just
forward of the mid flange. This
allows for the inspection of the
combustor, fuel nozzles and the
1st stage high pressure turbine
nozzle. Two (2) additional
borescope ports are located in theaft portion of the case to provide
access for the inspection of the
high pressure turbine blades and
nozzles.
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Slide 68
COMPRESSOR REAR FRAME
AFT CASE (DLE)
CRF aft case provides the transition
from the CRF to the TMF. Located
in the CRF aft outer case are the
stages 1 and 2 nozzle assemblies.
The CRF aft case supports the clap
traps. Two (2) borescope ports are
provided in the aft portion of thecase for inspection of the turbine
blades and nozzle.
Compressor Rear Frame
SAC
Same as base except 2nd T3 port
has been added
B
Made of
Inconel 718
CDP discharge
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Slide 69
DLE CRF
B
(6 ea)
Fire eyes UV Flame Detectors (2 ea)
With air cooled sapphire lenses
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Slide 70
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Slide 71
Compressor Rear Frame Assembly
#4B
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Slide 72
Customer Bleed
In SAC applications high pressure
air can be extracted from the
compressor discharge chamber
for anti-icing of the inlet ducts.
High pressure airflow for
customer use, is supplied through
a customer bleed chamber
located within the CRF cavity.High pressure air to supply the
flow, passes into the customer
bleed chamber through holes in
the CRF.
A baffle forming the aft wall of the
chamber reduces Ps3 fluctuations,
these fluctuations are caused by
load variations reflected through
the bleed air piping.
Ports machined into CRF struts 3,
4, 8 and 9 route the air to
manifolds mounted to the left and
right-hand sides of the engine.#4 Bearing Thrust Balancing
The CDP seal support and the
HPT rotor forward shaft form the
#4 Bearing Thrust Balance
Chamber.
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Slide 73
During engine operation, the
compressor exerts a forward
thrust load on the #4B bearing.High Pressure air in the thrust
balance chamber exerts an aft
directed force on the HPT rotor to
counteract the forward directed
thrust load.
Frame Vent and HP Recoup
From the CDP seal mini-nozzles,
air leaks in the forward direction
across two rotating seals to
supply the Frame Vent HP
Recoup flows.
Frame vent air leaks into an
isolation chamber surrounding the
B Sump, and continues flowoutward to secondary pressure
through ports machined into CRF
struts 7 and 10.
This flow cools the sump area
and prevents fouling of the CRF
cavity in the event of sump oil
seal failure.
HP Recoup air is routed to the
forward side of the CRF through
series of tubes, combined with
high pressure seal leakage air onthe aft end of the compressor
rotor, and ported out of CRF
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Slide 74
struts 5 and 6. The air pressure is
used to regulate bearing loads on
the high pressure system.
External piping carries the HP
Recoup flow into the TMF. There
it cools the area between the
frame and the TMF liner, before it
is released to the main gas flow.
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Slide 75
Thrust Balance
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Slide 76
Bottom View
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Slide 77
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Slide 78
High Pressure Recoup
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Slide 79
HP Recoup
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Slide 80
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Combustion System/Fuel System
Available with standard annular or dry low emissions combustors
DLE combustor same design provided on the LM2500
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Slide 82
Made of
Hastelloy X
120 lbs
Strut
Clearance
Small holes=film cooling
Large holes=Dilution
Fishmouth seals
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Slide 83
A=Outer ring
B=Pilot ring
C=Inner ring
3 zones
75 premixed
areas
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Slide 84
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DLE vs. Standard Combustor
With dry low emissions combustor
With standard combustor
DLE requires a lower heating value to be
800-1200 Btu per standard cubic foot and
Less than 300 deg. F supply tempLess than 25 ppm Nox
25 ppm CO
15 ppm UHC
2 PX36 combustor dynamic pressure 0-10 psi
2 flame detectors 0-1(on or off)
Heat shields are investment cast
Impingement and convection
cooled
Combustor is TBC coated and has
No film cooling
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Slide 86
Combustor
The combustor is mounted in the
compressor rear frame on 10
equally spaced mounting pins in
the forward low temperature
section of the cowl assembly. The
mounting hardware is enclosed
within the CRF struts so that it will
not affect airflow.The combustor is annular and
consists of the following
components riveted together:
1. Cowl assembly
2. Dome
3. Inner & outer liner
Cowl Assembly
The cowl assembly in conjunction
with the compressor rear frame,
serves as a diffuser and distributor
of compressor discharge air. The
cowl furnishes air to the combustion
chamber, providing for uniform
combustion and even-temperature
distribution at the high pressureturbine.
Dome
The dome provides flame
stabilization and mixing of fuel and
air. The interior surface of the dome
is protected from the high
temperatures of combustion by a
cooling air film.
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Inner & Outer Liner
The combustor liners are a series of
overlapping rings joined by weldedand brazed joints. They are
protected from the high combustion
heat by circumferential film cooling.
Primary combustion and cooling air
enters through closely spaced holes
in each ring. These holes help to
center the flame, and admit the
balance of combustion air. Dilution
holes are employed on the outer
and inner liners for additional mixing
to lower the gas temperature at theturbine inlet.
Combustion Section/Triple
Annular Combustor
The LM2500+ DLE GT utilizes alean premix combustion system
designed for operation on natural
gas fuel.
The combustor is of a triple
annular design consisting of five
major components: cowl
(diffuser) assembly, dome inner
liner, outer liner, and baffle.
The triple annular configuration
enables the combustor to operate
in a uniformly mixed lean fuel toair
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Slide 88
ratio (premix mode) across the
entire power range, minimizing
emissions.
The head end or dome of the
combustor supports 75 segmented
heat shields that form the three
annular burning zones in the
combustor, known as the outer or
A-dome, the pilot or B-dome, andthe inner of C-dome. In addition to
forming the three annular domes,
the heat shields isolate the
structural dome plate from hot
combustion gases. The heat
shields are an investment-cast
superalloy, are impingement and
convection cooled, and have a
thermal barrier coating. The
combustion liners are aft mounted
with thermal barrier coating and no
film cooling.
Gas fuel is introduced into the
combustor via 75 air/gas
premixers packaged in 30externally removable and
replaceable modules. Half of these
modules have two premixers, and
the other half have three. The
premixers produce a very
uniformly mixed, lean fuel/air
mixture.
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Slide 89
High Pressure Turbine
The high pressure turbine rotor
(HPTR) extracts energy from thegas stream to drive the
compressor rotor. The HPTR and
the compressor rotor are directly
coupled by means of a spline and
coupling nut. The HPT nozzles
direct the hot gas from the
combustor onto the HPTR blades
at the optimum angle and velocity.
The high pressure turbine (HPT)
consists of :
1. High pressure turbinerotor (HPTR)
2. 1st stage nozzles (HPTN1)
3. 2nd stage nozzles (HPTN2)
4. Turbine Mid Frame (TMF)
High Pressure Turbine Rotor
(HPTR)
The HPTR has two stages of
blades. Each stage of blades are
retained in its respective disk by
axial fir-tree slots. Both sets of
blades have long hollow shanks
which prevent heat from being
convected to the rotor, and allow
cooling air that enters the rotor to
exit, thereby cooling both bladesand rotor. The
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Slide 90
cooling air that enters the bladeshank is serpentined throughthe blade to distribute thecooling evenly.
High Pressure Turbine Rotor
Cooling
Cooling air enters HPT rotor
forward shaft, provides a cooling
flow to the rotor cavity and disks,
then is discharged through the
rotor blades.
Stage 1 blades are cooled by a
combination of internal
convection, leading edge internal
impingement, and external film
cooling.
Stage 2 cooling is accomplished
entirely by convection.
Cooling channels within the
blades are serpentine to ensure a
uniform temperature distribution
across blade surface.
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Slide 91
Stage 1 Blades
Stage 2 Blades
Approx. 2200 deg F
CDP
Forward
Shaft
Disks are made of
Inco 718
Laminar
Flow
Cooling
Sacrificial
=RENE 80
=RENE 80
450-500 deg F
Cooler than stg 1
Internal convection& external film
cooling
Convection cooled
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Slide 92
HPT Rotor Cooling
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HPTN1 Cooling
Impingement, convection and film
cooling circuits within eachindividual HPTN1 vane are
supplied with high pressure
cooling air directly from the
compressor discharge chamber.
To distribute the cooling flows,
inserts are installed into forward
and aft cooling chambers
machined into the vanes.
High pressure air from the
compressor discharge chamber
enters the forward insert throughthe underside of the HPTN1
forward inner seal.
Holes in the insert impinge the
high pressure air directly against
the inner walls of the forwardchamber, displacing hot air, and
providing a continuous supply of
cool air to absorb heat directly
from the metal structure of the
vane.
Hot air displaced by the
impingement flow is carried out of
the vanes through nose holes by
convection.
Gill holes in side of the vane
maintains a thin layer of filmcooling air between the metal
structure of the vane and the hot
combustor discharge gases.
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Slide 96
Impingement and convection
cooling circuits in the aft chamber
function similar to those in the
forward chamber. Film cooling is
not provided.
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Slide 97
Knife edge seals
10 pins, silver coated
For anti-siezing
Ignitor
Made of
X-40
Air goes into impingement inserts for even
Distribution, chambers have same area.
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Slide 98
Stage 1 High Pressure
Nozzle Cooling
Nozzle= converging duct which
Increases velocity and decreases
pressure
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Slide 99
Stage 2 Nozzles (HPTN2)
The stage 2 nozzle is also made of
a pair of vanes. The nozzle vane iscooled by convection from 13th
stage bleed air that enters through
the cooling air tubes and cools the
center area and leading edge.
Some of the air is discharged
through holes in the trailing edge,
while the remainder is used for
cooling the inter-stage seals and
the HPTR blade shanks.
13th Stage Parasitic Flows
HPTN2 Cooling
Delivered through the CRF casingat four different locations (2 per
side), and flows through air tubes
on the nozzle support into the
individual nozzle vanes.
Inserts installed in the vanes are
divided into forward and aft
chambers.
Cooling in the forward chamber is
by convection and impingement.
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Slide 100
Cooling in the aft chamber is
by convection.
Cooling air released through
the bottom of the vanes
provides cooling to the HPT
rotor thermal shield and
interstage seal.If shroud clearance is too large, more
Fuel is needed which=more temp
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Slide 101
PARASITIC AIRFLOWS
Parasitic airflows supplied through
the compressor discharge chamberare provided to supply customer
bleed air requirements and the
following cooling and
pressurization functions.
HPTN1 Cooling
HPT Rotor Cooling
#4B Bearing Thrust Balancing
B Sump Isolation and Cooling
(Frame Vent)
TMF Liner Cooling (HPRecoup)
Turbine Mid Frame
The turbine mid frame (TMF)
supports the aft end of the HPTR,and the forward end of the power
turbine rotor.
The TMF is bolted between the
CRF and the power turbine stator
case and provides a smooth
diffuser flow passage for the HPT
exhaust gas into the power
turbine.
The stage 1 power turbine nozzles
are attached to the rear of the
TMF.
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Slide 102
Turbine Mid Frame Strut and Liner Cooling
HP
Recoup
9th stage
P4.8
Liner is aerodynamically shaped for smooth airflow
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Turbine Mid FrameMade of Inco 718, Hastelloy X and HS 188
8- T4.8 probes
Ground handling mounts deleted from Plus
#5 brg- supports aft end of HPT
#6 brg- supports forward end of PT
PTs are attached here
GE, Dresser, Pignone, Ruston
If oil is present, seal is leaking
C
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Slide 104
Six Stage Power Turbine-Low Speed
Six stage power turbine (3,600 rpm design point)
-10% increase in flow function for 20% increase in airflow
-Modified stage 1 blade and nozzle, stage 5 and 6 blades
-Stage 1-3 nozzles supported from new casing liners to isolate
casing from flowpath temperature.
-Disks and drive train strengthened for higher torque loads
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Power Turbine
The power turbine is composed of :
1. Low Pressure Turbine Rotor
2. Low Pressure Turbine Stator
3. Turbine Rear Frame (TRF).
The Power turbine is
aerodynamically coupled to the gas
generator and is driven by the gas
generator exhaust gas.
Low Pressure Turbine Rotor
The power turbine rotor is a low
pressure rotor consisting of 6stages of blades. Each stage of
blades is retained in its own disk
by axial fir-tree slots, and
incorporate interlocking tip
shrouds to prevent blade tip
vibration.
Rotating seals are secured
between the disk spacers, and
mate with the stationary seals to
prevent excessive gas leakage
between stages.
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Slide 106
Low Pressure Turbine Stator
The power turbine stator consistsof:
1. Two (2) Case halves splithorizontally.
2. Stages 2 though 6power turbine nozzles
3. Six (6) stages of bladeshrouds
4. Five (5) stages of interstageseals
Case Halves
The power turbine stator casehalves are the improved thick flangedesign. They are amachined/matched set of cases.This means that damage
sufficient to cause the replacementof one half, will result in thereplacement of both halves.
Power Turbine Nozzles
The power turbine nozzles providepressure recovery and direct theexhaust gases of the gas generatoragainst the rotor blades. The stage1 nozzles are connected to, and
considered part of the turbine midframe. Stages 2 through 6 arebolted to the power turbine statorcase.
Blade Shrouds
The blade shrouds are ahoneycomb material mounted incasing channels of the stator
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case. These honeycomb shrouds
mate with the interlocking tip
shrouds of the blades to provideclose-clearance seals, and to act as
a casing heat shield. Insulation is
installed between the
nozzle/shrouds and casing to
protect the casing from the high
temperature of the gas stream.
Inter-stage Seals
The stationary interstage seals are
attached to the inner ends of the
nozzle vanes to maintain low air
leakage between stages.
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Slide 108
Six Stage Power Turbine 6 Pack
9th Stg sump pressurization
7B 7R
Speed
Sensor
Ring
PT can only expand in forward direction
Seal added to prevent oil from entering
PT spool (revent)
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Turbine Rear FrameTurbine Case Half
Unfilled honeycomb
Made of Hastelloy
Antirotation lugs prevent
Nozzle rotation
Stg 1 nozzles are attached to Aft flange of TMF
Upper and Lower Cases are matched set
Monitor TB
D
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Slide 110
Turbine Rear Frame
The turbine rear frame (TRF) forms
the exhaust gas flow path for the
exhaust gases leaving the power
turbine, and provides support for
the aft end of the power turbine,
and the flexible coupling adapter
for the high speed coupling shaft.
The forward portion of the TRFouter casing supports the aft end of
the power turbine stator case, and
the aft portion supports the outer
exhaust cone. The outer case also
provides attaching points for the
gas turbine rear mounts.
Turbine Rear Frame
Frame vent
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The struts are hollow and contain
service lines for lubrication,
scavenge, and vent. The powerturbine speed transducers are also
mounted in the struts.
The hub of the TRF houses both
7B ball and 7R roller bearing
assemblies. The hub and bearing
housings have flanges to which air
and oil seals are attached to form
the D sump.
Flexible Coupling Adapter
The PT rotor terminates in a bolted
flange adapter. The purchasersflexible coupling mates with this
adapter.
Exhaust Components
The exhaust duct consists of an
inner and outer duct forming the
diffusing passage from the turbine
rear frame. The inner diffuser duct
can be moved aft to gain access to
the high speed coupling shaft. The
exhaust duct is mounted
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Slide 112
separately from the gas turbine,
and piston-ring type expansion
joints are used to accommodate
the thermal growth.
Note: The exhaust duct may not
be supplied as part of the gas
turbine.
Made of 321 stainless steel
Approximate weight is 2240 lbsWithout HSCS.
Not GE Supplied Anymore
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High Speed Coupling Shaft
The high speed coupling shaft
adapter is connected to the powerturbine rotor and provides shaft
power to the connected load.
The high speed coupling shaft
(HSCS) consists of:
1. Forward adapter
2. 2 flexible couplings
3. Distance piece
4. Aft adapter
Note: Flexible couplings, distance
piece and aft adapter may not besupplied as part of the gas turbine.
The forward and aft adapters are
connected to the distance piece bythe flexible couplings. The flexible
couplings allow for axial and radial
deflections between the gas turbine
and the connected load during
operation. Inside the aft adapter and
the rear flexible seal is an axial
damper system consisting of a
cylinder and piston assembly. The
damper system prevents excessive
cycling of the flexible couplings.
Anti-deflection rings restrict radialdeflection of the couplings during
shock loads.
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Slide 114
Must be less than 20 gram inches of unbalance
Max diameter of 24
Body bound bolts
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7B Bearing Thrust Balancing
A portion of 13th bleed air is
delivered into TRF through strut #8.The airflow is then ported into the
7B bearing thrust balance chamber.
Aft wall of chamber is formed by a
thrust balance seal mounted to the
TRF hub. Forward wall is formed by
the power turbine aft air seal
mounted to the LPT rotor.
Air pressure inside the chamber
exerts a forward directed force on
the LPT rotor to counteract aft
directed thrust
forces caused by the main gas
flow operating against the LPT
rotor blades.The #2 strut of the TRF has a
plate over it, it maybe used by the
packager to measure the pressure
in the thrust balance chamber.
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Slide 116
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Bearings
The LM2500 Plus contains seven
sets of bearings. Five of these setsare roller bearings numbered form
3R to 7R, and the remaining two
sets are ball bearings numbered
4B and 7B. These bearings are
used to support two separate
rotating systems; the gas generator
and the power turbine.
Support for the gas generator rotor
consists of:
1. 3R bearing in A sump
supporting the forwardcompressor shaft.
2. 4R bearing in B sump
supporting the aftcompressor shaft.
3. 4B bearing in B sump
carrying the thrust loads.
4. 5R bearing in C-sump
supporting the aft high
pressure turbine shaft.
Power turbine support consists of:
1. 6R bearing in C sump
supporting the forward
power turbine rotor shaft.
2. 7R bearing in D sump
supporting the aft power
turbine rotor shaft.
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Slide 118
3. 7B bearing in D sump
carrying the thrust loads of the
power turbine rotor.
NOTE: The rolling member of 6R
bearing is mounted in the TMF.
Mounting
All bearing outer races, except 4B,
5R and 7R are flanged. The 4B
bearing is retained by a spannernut across its outer face. The 5R
and 7R bearings are retained by a
tabbed ring which engages slots in
the outer race.
Bearing 3R and 5R, under some
conditions, can be lightly loaded.
To prevent skidding of the rollers
under these conditions, the outer
race is very slightly elliptical to
keep the rollers turning.
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Two Stage Power Turbine
Supported by 2 hydrodynamic journal bearings
and 1 hydrodynamic thrust bearing.
Total weight is 21,243 lbs!
Rotor weighs 4919 lbs.
3 reluctance type NPT sensors
Exhaust frame/TRF has 6 equally spaced struts.
6 ejectors are used to mix bleed air and ambient
Air for cooling of struts (54 psi,375 deg F, and
.180 lbs/sec.
PT stator is made up of transition case, 1st stage
Case w/40 shrouds and 2nd stage case w/ 40 shroud
Transition case mates
To GG TMF flange,
Fwd flange is nickel baseAlloy, rear flange is
Carbon steel.
Off engine lube system
ac motor driven pump
heat exchanger, filters
and tank not on GG
Required oil is ISO VG32
mineral oil w/supply
pressure approx 22 psi
@122-140 deg F
PT wheelspace temp has
8 t/cs for monitoring
cooling air temp between
turbine disks and disk
cooling cavities
Rated at 6100 rpm/ 40,200 hp
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Two Stage Power Turbine
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Two Stage Power Turbine
6,100 rpm Design Point
M&I is providing a two stage high speed power turbine option
HSPT being sold to packagers for mechanical drive and otherapplications where continuous shaft output speeds up to 6,400 rpmare desirable
Design will be more industrial than aeroderivative
Weight ~22,000 lbs.
Hydrodynamic bearings
Design speed 6,100 rpm; operating speed 3,050-6,400 rpm
Direction of rotation is clockwise (aft looking forward)
Overall efficiency for gas turbine > 40% @ 40,200 SHP (29,980 KWs)rating (ISO)
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Slide 122
Industrial Gas Turbine
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Accessory Drive Section
The accessory drive section consists
of:1. Inlet gearbox (IGB).
2. Radial driveshaft.
3. Transfer gearbox (TGB).
Power to drive the accessories is
extracted from the gas generator at
the front of the compressor, through
a large diameter hollow splined
shaft. The IGB is bolted to the
compressor front frame and mated
to the compressor shaft through the
splines. The IGB then transfers this
power to the radial driveshaft by
means of a
set of beveled gears. Another set of
bevel gears in the TGB receives the
power from the radial driveshaft, anddistributes it to the accessories
through a planetary gear train.
During a start sequence this
arrangement is reversed, with the
accessory drive section extracting
power from the starter, and
transferring it through the TGB to the
radial driveshaft, to the IGB, to the
gas generator.
Inlet Gearbox (IGB)
The inlet gearbox is bolted to thehub of the compressor front frame.
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Radial Driveshaft
The radial driveshaft is a hollow
tube externally splined at each end
allowing it mate with the IGB and
TGB. The radial driveshaft also
contains a shear section to help
prevent damage to the accessory
drive section.
Transfer Gearbox (TGB)The forward section of the TGB,
also called the bevel gearbox,
contains the set of bevel gears and
a horizontal drive shaft which
transmits the power to the gear
train in the main body of the TGB.
An access cover in the bottom of
the casing facilitates removal
and installation of the radial
driveshaft.
In the main body of the TGB the
following may be removed and
replaced without disassembly of
the gearbox:
1. Gears
2. Bearings
3. Seals and adaptersassemblies
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splines
Sheer point
on top in case
of failure, IGB
can be removed
Aluminum
AMS 4218
Duplex bearings on
each bevel gear
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1.3 revolutions of compressor
Equals 1 revolution of ratchet
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LUBE
OIL
SYSTEM
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15-80 psi depending on oil temp
low temp=higher viscosity and
higher delta P on filters
Check valve prevents
gravity drain of
tank into engine
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Lube Oil System for G Series Engine
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RTDs for temp
detection
Positive displacement vane type
Pump, moves air and oilTo air/oil separator
Lube supply temps must be over
20 deg F for MIL-L-23699 or over
-20 deg F for MIL-L-7808 for VSVs
Control interlock- Lube pressure must be over 8 psi
At idle and 15 psi at 8000 rpm
Oil must be filtered to 10 micron nominal
Scavenge capability is approx twice that of supply
Scavenge temp is approx 160-275 deg F
W/ max of 340 degF
Maximum 3.5 psig head pressur
Supply 140-160 deg F
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Sump Philosophy
The LM2500 has 4 oil sumps, onein the hub of each frame. Thesumps are designatedalphabetically from front to back asA sump (CFF), B sump (CRF),C sump (TMF) and D sump(TRF).
The purpose of the oil sump is to
contain the lubricating oil, and notallow the oil to migrate to otherareas of the engine.
The design of the sumps do notallow oil to pool or collect. For thisreason they are called dry sumps.To accomplish this the oil iscollected or scavenged from thesump at about twice the rate ofsupply.
The oil is retained in the sump
through the use of slingers,
windback threads and air/oil seals.
Slingers are notched elements
mounted on the turbine shaft that
throw oil against the windback
threads.
Windback threads are stationaryelements containing threaded
grooves that route the oil back into
the sump.
The air/oil seals retain oil in the
sump by allowing pressurized air to
flow across the seal elements and
into the sump, thereby preventing oil
from flowing out of the sump.
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The sumps are vented to
ambient to promote this airflow.
Sump Philosophy
Seal is teflon or
Phonelic resin
Prevents oil from
hanging in this area
Approx. 18 psi
To A/O sep
Approx 40 psi
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Lube Supply and Scavenge Pump, Bottom View
300 psi relief valve
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Lube Supply & Scavenge
Pump Screens
Air/Oil Separator
Finger screens and
Electronic chip detectors
AGB,B,C,D & TGB
Usually ferrous material
is from bearings
Connection kit # 537L317G06
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FUEL
SYSTEMS
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Fuel Systems Liquid Fuel System
ALWAYS anti-seize bolts!!!!!
Suitable substitute=UNFLAVOREDPhillips milk of magnesia
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Natural Gas Fuel System(New Configuration)
Dual Fuel System(Natural Gas/Liquid Fuel)
VIEW FORWARD LOOKING AFT
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Liquid Fuel Shutoff Valve Liquid Fuel Pump & Filter
2 ea inline for dual redundancy
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Liquid Fuel Pump & Filter Liquid Fuel Filter
35 psi delta
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Natural Gas Fuel System
With Steam Injection (STIG) STIG Fuel Nozzle Steam Manifold
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Fuel Systems with
Nox Suppression
Liquid Fuel System
with Water Injection
Water injection temp= 80-90 deg F
Flame temp is lowered to reduce NOX
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START
&
IGNITION
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Hydraulic StarterVickers
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Hydraulic Starter Operating Principle
Oil in
Oil out to reservoir
Squash Plate
Input drive shaft to
drive starter
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Pneumatic StarterGarret (Air Research)
Unshrouded
Exhaust
Exhaust
CCW
FLA
Air/gas in
1200-1700 Ignition
And fuel added
Approx. 4500 rpm
Starter disengaged
Spring pushes on pall
CW ALF
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Pneumatic Starter with Continuous Lubrication
For gas application
From lube pump
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Pneumatic Starter Operating
Principle (Sheet #1)
Prior to Start, Engine Shut-Down
Pneumatic Starter Operating
Principle (Sheet #2)
Start Initiated
Air/Gas in
Exhaust
Approx.75,000 rpm
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Slide 153Location of Components in Housing
Converts 115V, 60 or 50 HZ
To high voltage
14.5-16 joules
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Igniter Immersion Depth
Immersion depth gauge
DLE measured to here per GEK 105048 Vol.II
WP 103, table 1
SAC to here
Maximum of 8 shims
Approx. .030 each
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SENSORS
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Inlet Sensors Lube Oil System
Temperature Sensor
P2
Pt2/T2
Duplex RTDs
T2 operates from 65 to 130 deg F
Pt2 operates from 0 to 16 psia
Dual element platinum RTDs
Read from 40 to 400 deg F
-40 to 204 deg C
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Gas Generator Speed sensor
Magnet creates frequency
off ferrous gear
2 each Reluctance type
Reads 100-12,000 rpm
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T3 Sensor Accelerometer
Operates from 40 to 2000 deg F
-40 to 1093 deg C
Piezoelectric
1 on GG @ CRF 0-4 ips velocity
1 on PT @TRF (6 pk) 0-2 ips velocity
@ Bearing support on 2 stage
Dual element thermocoupleAlumel/Chromel
Bypassed with GG
Speed less than 5500 rpm
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Vibration Sensors Gas Generator
Discharge T4.8 (T5.4) Temperature
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T4.8 (5.4) Thermocouple Harness T4.8 (5.4) Thermocouple
A
B
C
DE
F
G
H
Reads between
-40 to2000 deg F
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Gas Generator Discharge
Pressure PT4.8 (PT5.4) SensorOLD STYLE
Different lengths
Give gas path average
Reads 0- 125 psia
Magnesium
Oxide
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Slide 164Power Turbine Speed Pickups
Reads 0-10,000 rpm
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WATER
WASH
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On-Line Compressor Cleaning
A method of removing the build up
of deposits on compressorcomponents while the engine is
operating. On-line cleaning is
accomplished by spraying
cleaning solution into the inlet of
the engine while the engine is
operating.
Crank-Soak Compressor
Cleaning
A method of removing the buildup
of deposits on compressor
components while the engine ismotored by the starter. Crank-soak
cleaning is accomplished
by spraying cleaning solution into
the inlet of the engine while the
engine is operating unfired at crankspeed.
Liquid Detergent
A concentrated solution of water
soluble surface active agents and
emulsifiable solvents.
Cleaning Solution
A solution of emulsion of liquid
detergent and water or a water and
antifreeze mixture for direct engine
application. The recommended
dilution of liquid detergent and watershall be specified by the liquid
detergent manufacturer.
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B&B 3100 (solvent base)
ARDROX 6322 (solvent base)
R-MC Engine cleaner (solvent base)
Rochem Fyrewash (solvent base)
ZOK 27 and ZOK27LA (water base)
Turbotect 950 (water base)
Techniclean GT (water base)
Other detergents that meet therequirements of
MID-TD-0000-5.
For on-line cleaning RochemFyrewash, R-MC, B&B TC100,Trubotect 950 and Airworthy
ZOK27 have been used.
At present, only acceptable anit-
freeze solutions are:
Isopropyl alcohol
MEK (methyl ethyl ketone)
Acetone
Use of non-isopropyl alcohol,
ethylene glycol, or additives
containing chlorine, sodium, or
potassium is not permitted; they
might attack titanium and other
metals in the installation.
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Crank-Soak Cleaning Procedure
The temperature of the cleaning
solution and rinse water should be100 to 150F. If crank-soak
compressor cleaning is necessary
in below freezing weather, acetone,
MEK, or isopropyl alcohol can be
added to the water to prevent
freezing. See Appendix A5 (MID-
TD-0000-5) for antifreeze/water
mixtures.1. If the engine has been
operating, allow it to cool sothat the outside surfaces areunder 200F. Cooling can beexpedited by motoring
the engine on the starter.
2. Prepare a 20 gallon solution
of detergent and water. Theliquid detergent manufacturershould be contacted for therecommended dilution. Liquiddetergents meeting therequirements of MID-TD-0000-5 and water meetingthe requirements of MID-TD-0000-4 are acceptable. Thetemperature of the cleaningsolution should be 100 to150F.
3. Motor the engine with thestarter. After the gasgenerator stars to rotate,open the water supply valve
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Slide 170
to the spray manifold on theengine. When the gasgenerator reaches 1200 rpm,de-energize the starter, closethe water supply valve, andlet engine speed decrease to100 rpm. At 100 rpm,energize the starter, open thewater supply valve, andrepeat the cycle until thesolution is used up.
4. Allow the engine to coast to astop, wait a minimum of 10minutes, and then rinse byspraying 40 gallons of waterthrough the spray manifoldwhile motoring the enginebetween 100 and 1200 rpm
until the water is used up.
5. Blow residual water from thespray manifold withcompressed air.
6. Start the engine and operateit at idle for 5 minutes to dryit.
On-Line Cleaning ProcedureRecommended flow rate of the
cleaning solution is 5 +/- 1 gpmwith engine operating above8500 rpm. Recommendedmaximum duration of on-linecleaning is 10 minutes perwash, and the recommendedmaximum cleaning solution useis 100 gallons per 24 hour
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period. Performance monitoringmay indicate that this frequency
and duration of washing shouldbe adjusted. The temperature ofthe cleaning solution should be100 to 150F. If heated wateris not used, it shall not be colderthan ambient air at the time ofcleaning. Cleaning solutionshould not be injected at anambient air temperature lowerthan 50F. If it is necessary toon-line clean at lower ambienttemperatures, an antifreezesolution will be required. See
MID-TD-0000-5 (Appendix A5)for antifreeze mixtures.
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