Slide 1

Welcome to thePresentationOn Frame 9e Gas TurbineParadip Refinery Project (PDRP)

A Sunrise Project for a Sunshine FutureCOVERAGEFUNDAMENTALSFUNCTIONAL DESCRIPTION SUPPORT SYSTEMOPERATIONPROTECTIONS

TEMPTURB

ENTROPYCOMP

COMBCOOLING1234VOLUMECOMBTURBCOOLINGCOMP1234PRESSUREBRAYTON CYCLE

Compressed AirHSD/Naphtha / Natural Gas

Gas Turbine

ExhaustGasHRSGSteamTurbineGT GeneratorBypassStackST GeneratorCombined Cycle Power Plant

5AirFuelExhaust gasSteam TurbineSteamGGCombined Cycle Power PlantHRSG15%100%33%16%36%Gas TurbineInputCondensorTo Process UnitsCooling Tower

STARTING MOTORAccessory Gear BoxINPUT GEAR BOX & TORQUE CONVERTERATOMAIRCOMPFUELPUMP

MOP

MHOP

AIRFILTERFUEL

COMB

TURB

DIVERTERDAMPERHRSGBY PASSSTACK

GEN

EXC

MAIN COMP

BLOCK DIAGRAM OF GTTURNING GEAR MOTOR & CLUTCH ASSEM.

INLET FILTER HOUSESILENCERINLET DUCTACC. COMPINLET PLENUMTUR.COMPEXHAUT PLENUMSTACKHRSGSILENCERINLET AND EXHAUST SYSTEM

INLET & EXHAUST SYSTEM Gas turbine compressor sucks fresh & clean air from inlet air filter system through inlet plenum.

Hot exhaust gases produced as the result of combustion in turbine is released to atmosphere through exhaust plenum.

The noise generated during gas turbine operation is attenuated by means of absorptive silencing material and devices built in the inlet and exhaust plenum.

Axial flow type with 17th stages.

Each stage consist of rotating row of blades that increases the velocity of incoming air raising it kinetic energy, followed by a stationary row of blades that act as diffusers converting K.E to pressure increase.COMPRESSORCompressor air is used for following purposesCombustion of fuel in the combustion chamber.Cooling of various TURBINE Parts.Sealing of oil in the bearings.Atomization of liquid fuelPurging of Turbine hot gas path

The combustion system is the reverse flow type. The high-pressure air from the compressor reverses its path in the transition pieces and then moves to the annular spaces that surround each of the ten combustion chambers. The airflow through the combustion chamber has three functions:To oxidize the fuel. To cool the metal parts. To dilute the extremely hot product of combustion to the desired turbine inlet temperature.

Combustion SectionEach combustion chamber has the following main parts:

Nozzle flow sleeve Liner Transition piece Cross fire tube Spark plugs (2 nos.) Flame detectors (4nos)

Reaction zoneRetractableSpark plugFuel nozzleCross fire tubesAir from compressorTransition pieceMixing zoneCooling airDilution zoneCombustion linersTo Turbine nozzleReverse flow combustion system

i) TRANSITION PIECESIt directs the hot gases from the liners to the turbine nozzle.ii) NOZZLESIt disperses and mixes the fuel with proper amount of combustion air.iii) CROSS FIRE TUBESA passage to propagate the flame from one combustion chamber to another after the initiation of fire by spark plug.iv) COOLING OF LINER WALLA film of main compressor discharge air shields the liner wall from the hot combustion gases.

v) COMBUSTION CHAMBER

In the combustion chamber, hot gases from the reaction zone passes to the dilution zone where additional amount of air is mixed to bring the temperature of hot gases to the desired level.

vi) SPARK PLUGCombustion is initiated by the spark plugs provided in the two combustion chambers where the firing command is given by mark-VIe. the spark plug operates at the voltage of 11 kV and this high voltage is supplied by ignition transformer. Spark plugs are installed in combustion chamber no-13 and 14 only. At the time of firing, spark plug ignites the fuel in the combustion chamber and fire in the remaining chambers is ignited through crossfire tubes. The spark plug are spring injected and pressure retracted type. As the rotor speed increases, chamber pressure causes the spark plugs to retract and the electrodes are removed from combustion zone. As the rotor speed increases, chambers are ignited through crossfire tubes only.vii) ULTRA VIOLET FLAME DETECTORSDuring the starting sequence, it is essential that indication of the presence or absence of flame in the combustion chambers be transmitted to the mark-V. The four nos. flame detectors are provided in combustion chamber 4,5,10 and 11 to meet the purpose.

viii) FUEL NOZZLESEach combustion chamber has one nozzle and each nozzle has four inlets for Natural Gas, Liquid Fuel, Purge Air, and Atomizing air. The liquid fuel is atomized by means of atomizing air. The swirl tip in the nozzle imparts a swirl in the combustion air for complete combustion and resulting in the smoke free operation of the unit.

GAS TURBINE SUPPORT SYSTEMLube Oil SystemTrip Oil SystemHydraulic Supply SystemLiquid Fuel SystemAtomizing Air SystemCooling and Sealing Air SystemStarting SystemCooling Water SystemHeating and Ventilation SystemFire Protection SystemInlet Air Filtration System

LUBRICATION SYSTEM

Three main turbine bearingsGenerator bearingsTurbine accessory gearControl fluid for hydraulic control devicesTrip Oil devices

Lubrication system major components includes: Lube oil tank in the turbine base Main lube oil pump (shaft driven from accessory gear) Auxiliary lube oil pump Emergency lube oil pump Pressure relief valve VR1 in the main pump discharge Lube fluid heat exchangers Main lube filters Bearing header pressure regulator VPR2

AGGMECWEOPAOP TRIP OILLUBE OILHEADERJBOR-1OR-3OR-2Mist EliminatorTo MOPOR-1 TO MHOPOR-2 TO ST.MEANSOR-3 TO AHOP

LO TANKGT LUBE OIL SYSTEM

VPR-2JOPCWF-1F-2CTHYDRAULIC SYSTEM

Hydraulic supply system provides the pressurized hydraulic oil required for operating the control components ( stop valve & control valve) of the GT fuel firing system and variable IGV mechanism.Main hydraulic oil pumpAuxiliary hydraulic oil pumpSystem filterTransfer valve & Hydraulic supply manifold assemblyLFBV actuator Inlet guides vane control valve & actuatorHYDRAULIC SYSTEM MAJOR COMPONENT INCLUDES:

OR-1ACC GEARMHOPAIR RELIEF VALVEAIR RELIEF VALVEPR.RELIEF VALVEPR.RELIEF VALVEAHOPOR-3HYD FILTER ASSEMBLYHYD ACCUMULATORSOH-3OH-4TO LIQUID FUELTO IGVGT HYDRAULIC SUPPLY

TRIP OIL SYSTEM

To Liquid fuel systemTo IGV system20FL-120TV-14.7 mm orfice2.36 mm orficeOIL From LO HdrTRIP OIL STSTEM27Off Base Lube Oil(Warren Pump) System

Tur.legsCW OutWarren pump oil coolerLube oil H.EFlame detectorsWater to water H.EVTR-1CW INCOOLING WATER SYSTEM

LIQUID FUEL SYSTEM

GT HSD FORWARDING SYSTEM 25 Filter25 Filter6 Filter6 FilterTo GTFrom HSD pumpsPCVPCVPCVPCVFrom Naphtha pumpsLRLR3 Way Valve 2m3 2m3 Naphtha Drain TankHSD Drain TankGT False Start DrainGT Purge DrainSlope Tank

Fuel inletPG

PSHydraulic oilStop valveFuel pumpLimit switchFlow divider magnetic pickupServo valveHyd. oilOH-3Control valveSelector assemblyConn. for purge airTypical for 14 nozzlesDrain manifoldSCHEME FOR LIQUID FUEL SYSTEMBRG#1BRG#2COMPTURBAE-5AE-11AE-11AD -1AD-2AD-3AD-8AD-4CPDVA2-2VA2-1EXHAUSTPLENUM88TK-188TK-2 AD-2: False start drainAD-3: APUAD-8: AA AD-5: Brg SealingSEALING AND COOLING SYSTEM

INLET AIR FILTER UNITREQUIREMENTTo provide protection against effects of contaminated air that may degrade GT performance.

To avoid GT life reduction by erosion, corrosion, fouling, plugging of cooling passages.

To avoid particles impact on internals of GT & consequent removal of metals particularly on leading & trailing edges of compressor blades.

Size-20 micron & above are most erosiveSize-20 micron & below are much erosiveATOMISING & PURGE AIR SYSTEM

Purge air manifoldAtom. air manifoldCombustionchamberTypical for10 nozzlesTo liquid fuel nozzlesCopm. dischSCHEME FOR ATOMIZING AIR20PL20AAVA18VA1920ABVA22BoosterCompressor MotordriveAccessory gear driveAtomizing Air Pre Cooler

CIRCULATING DM WATER SYSTEM Surge TankDM Water INCW OutCW INAA INAA OutDM Circulating PumpsVTR-2Atomizing Air Pre CoolerWater to Water H.E

FH6-1INOUTTRIP RELAYHIGH PINDICATOROH-496TV-1,2OLT-5CLOSEOPENINLETGUIDEVANERINGHM3-1OLT-1TRIPOILHYDRAULIC SUPPLYDVH3-1SCHEME FOR IGV SYSTEMB3RP2190TV-1SERVOVENTILATING SYSTEM

88BA-1,288BT-1,288EX-1,2Acc..Compt88NSTurbineCompt.Exh.Compt.Load Tunnel Compt.Air IntakeAir IntakeAir IntakeVENTILATING AND HEATING SYSTEMCO2DampersWith flame established Turbine compartment vent fan and Accessory compartment vent fan will start.

At GT speed > 8.4 % (430 RPM), Load gear compartment vent fan will start.

88VG-1,2Air IntakeCOOLING WATER SYSTEM

In gas turbine, the cooling water system circulates water as a cooling medium to perform following functions:

a) Heat dissipation requirement of lubrication system.(Lube oil heat exchangers)b) Turbine support legs cooling.d) Flame detectors cooling.e) Warren pump oil cooler.

The cooling water is supplied at a pressure of 2.0 - 2.5 kg/cm2. In the heat exchanger, cooling water flows through tubes and lube oil through shell. The water flow through the heat exchanger is regulated by a temperature-actuated valve VTR1, which has a sensor, installed in the lube oil header downstream from the heat exchangers.

INLET & EXHAUST SYSTEM Gas turbine compressor sucks fresh & clean air from inlet air filter system through inlet plenum.

Hot exhaust gases produced as the result of combustion in turbine is released to atmosphere through exhaust plenum.

The noise generated during gas turbine operation is attenuated by means of absorptive silencing material and devices built in the inlet and exhaust plenum.

ACCESSORY GEAR BOX

Why Air filtration?Erosion of compressor & hot gas path componentsCompressor FoulingCompressor corrosion by wet deposits of sea salts & acidsCooling passage plugging

Typical Air flowsFr-5 123 kg/sFr-6 137 kg/sFr-9 475 kg/s

INLET SYSTEM

Static-barrier (Multi stage)Self cleaning

Environments: Clean Rural - Static Dusty Urban Static + Pre filter or Self cleaning Contaminated Sea coasts, Chemical, cement, smokes Static + Pre filter or Self cleaning Desert Sand - Self cleaning

INLET SYSTEM

4 INCHES H2O INLET DROP RESULTS IN: 1.50% POWER OUTPUT LOSS 0.50 % HEAT RATE INCREASE 1.2 DEG.F EXHAUST TEMP. INCREASE

PRESSURE DROP EFFECTS

INLET SYSTEM

Air filtration systems Suitable for ..

Desert

Clean

.. All environments, Desert, Marine and Clean

Marine

48Inlet Air Filtration System- Paradip Frame 9E Gas Turbine

Two stage filtrations

1st stage Non woven bag filters2nd stage Glass fibreNo Pulsation cleaning required Suitable for desert/marine applicationAdvantages:

1st Stage Pre filter2nd stage fine filter

Receives the exhaust gases exiting from the side of the exhaust plenum & leads to stackInternally insulated exhaust ductExhaust silencer in Bypass stack

EXHAUST SYSTEM

Straight up AxialHorizontalConfigurations: 4 INCHES H2O EXHAUST DROP RESULTS IN : 0.50 % POWER OUTPUT LOSS 0.50 % HEAT RATE INCREASE 1.2 DEG.F EXHAUST TEMP. INCREASEPRESSURE DROP EFFECTS

EXHAUST SYSTEM

Carbon steel outer shellInsulation: ceramic fiberLagging: SS - ASTM A176 TY409Silencer panels: SSASTM A 176 TY409 Perforated coveringMineral wool fillSelf supported stack, emission ports, platforms & ladders

EXHAUST SYSTEM Diverter dampers Guillotine dampers By-Pass stacks Exhaust Silencers Suitable to any lay out Internally insulated

Design features: Low pressure drop Parallel baffle absorptive silencer Low heat loss Low exterior surface temperatures

54Electrically operatedToggle arm typeFlap movement by toggle lever mechanismDuplex seals Sealing efficiency:99.98%with out pressurization 100% with pressurization)Seal material :Super alloy INCONEL 625Ceramic wool Insulation (128kg/m3) thk250mm2x100% Seal air fans

DIVERTER DAMPER

ActuatorGear BoxToggle armSealing arrangementDamper bodyFlapSeal air fansIsolation valves

Major ComponentsDIVERTER DAMPER

Seal arrangement

DIVERTER DAMPER

Insulation fixing detailElectrically operatedRack and Pinion driveBonnet constructionBlade Assembly2x100% Seal air fansSeal material :Super alloy INCONEL 625Ceramic wool Insulation (128kg/m3) thk250mmGUILLOTINE DAMPER

ActuatorGear BoxRack & pinionBonnet Damper bladeSeal air fansIsolation valve

GUILLOTINE DAMPER

Major Components

Noise containmentThermal protectionFixed volume for fire protectionExterior appearance for packageSupport live and dead loads

ACOUSTIC ENCLOSURES For Noise attenuation , Thermal protection..and Safety for the equipment

ACOUSTIC ENCLOSURES ON BASE OFF BASE

Noise attenuation On base enclosure - 93dBAOff base enclosure - 85dBA

VENTILATION SYSTEM2 x 100% vent fans for GT enclosure2 x 100 % vent fans for load Tunnel compartment Ventilation air exhausts to atmosphere (top of enclosure)Louvered dampers for enclosure openings

Types of ventilation Induced draft ventilation Positive ventilation

To maintain safe temperature within enclosure Heat dissipation to maintain safe temperature within enclosure .

FIRE PROTECTION SYSTEM CO2 Clean Agent (FM-200)

Total Flooding type as per NFPA1263Fire extinguishing methodsTotal flooding systemLocal application systemHand hose line systemStandpipe system and mobile supply

Total Flooding SystemFire fighting for fixed volume and enclosed spaceSupply of CO2 arranged to discharge into and fill to the proper concentration.Leakage of CO2 from the enclosure to be kept at minimum and any leakage to be compensated with extra Co2 supply

FIRE PROTECTION SYSTEM

FIRE PROTECTION SYSTEMS Co2 based fire protection system for GTG Initial & extended discharge for GT Main & standby discharge for generator Heat rise detectors mounted inside enclosures Co2 cylinder bank in an off-base enclosure Co2 operated latches for dampers Microprocessor based addressable control panel

Total Flooding type as per NFPA12

PRINCIPLE OF WORKINGInitially a quantity of CO2 greater than 34% of the compartment volume is discharged in one minuteOxygen concentration is reduced from 21% to less than 15% in the enclosureExtended discharge to maintain the required concentration for a period of 20 to 40 minutes to minimize the re-flash conditionAutomatic shut down of all ventilation fans and ventilation dampers are actuated by CO2 latches

FIRE PROTECTION SYSTEM

FIRE PROTECTION SYSTEM

EXHAUST FRAME BLOWERSTwo motor driven centrifugal BlowersInlet screen & silencerAir to turbine shell, exhaust frame via strut passages (Annular space)

For a typical Fr 9EFlow: 12400 CFM with two fans in operationEmergency:620 CFM with one fan in operationMotor rating :100HPTo cool the exhaust frame

NOx ABATEMENT SYSTEMS Water Injection

Steam Injection

In harmony with nature..

69WATER INJECTION SYSTEM

Provides water to the combustion system of Gas turbine to limit the level of nitrogen oxides (Nox )in the turbine exhaust.Schedules water flow to the turbine as a function of total fuel flow, relative humidity and ambient temperature. Supplies treats water at the required flow rate and pressure to the combustion system of GT.

Water is injected into the combustion reaction zone, reducing the peak flame temperature , thus controlling NOx emissions.

Power output increase due to increase in mass flow rate.Water injection skid(off-base)Multi stage water pump (motor driven)Flow meter for flow controlShut off valveDM water requirementSystem suitable for NOX target42ppm for natural gas65ppm for distillate #2

WATER INJECTION SYSTEM

Off & On line water wash systemWater wash on a skid located off-baseWater storage tank and heatingWater pumping systemDetergent storage and pumping systemCommon skid for each site

For heavy fuels turbine washing envisagedUse of detergent for cleaningOn-line washing reduces need for frequent

COMPRESSOR WATER WASH SYSTEM

Water tankDetergent tankDetergent pumpwater pumpOn-line manifolds and nozzlesOff-line manifold and nozzlesWATER WASH SYSTEM:High speed rotating machinery: High temperature and shearing action in bearings generates a large volume of very fine oil mist (droplets) plus a considerable amount of vapor Always maintain MOT Vacuum at -50mmWC at Base load operation of Gas turbineOil mist and oil vapor is vented from the lube oil tank, it causes a visible plume Stringent environmental laws and regulations at all government levels Coalescers combine small aerosols through the filter media to form large droplets. MIST ELIMINATOR

MIST ELIMINATOR Removes oil mist entrained in the LO vaporDemister pads-SS316 wire meshCoalescing filter element(99.97% for droplets and particles 0.3micron and larger)Outlet oil content not more than 5ppm by weightCentrifugal blowers (2 Nos) and motors

OPERATION

Pre Startup Checks:AC Lube Oil Pumps ON in Auto & Turning Gear motor operation is OK.EOP is testedAll MCC modules are switched ON' and are kept on AutoMain Oil Tank Lube Oil Level is OK & Oil temp. normalVisual Inspection of Machine is OKCHECKS DURING STARTUPFiring is Established in all Flame ScannersExhaust Temperatures are uniformAcceleration is Smooth and Time taken is in line with start up curvesRise in Exhaust Temperature is UniformExhaust Temperature profile is OK Spread Values are within LimitsRise in Wheelspace Temperature is UniformVibrations are within Limits and as per earlier valuesBearing Oil Drain Temperatures are Normal

77MACHINE DOS & DONTSDo not Force any Logic for StartupDo not attempt Subsequent Starts Without Troubleshooting if M/C trips during StartupRecord the trends & Analyze present Operation>>Load Vs Exhaust Temperatures>>Load Vs CPD>>Load Vs FSR>>Load Vs VibrationUse Vast Data from Mark VIe to Notice incipient Problems

STANDBY INSPECTIONWhen Unit is not run for a long time

Run the AOP once in a week along with Turning Gear operationCrank the Turbine once in a Fortnight to drive away MoistureCheck Battery system, Oil levels etc.

Normal Start up/ Shut DownCHECK LIST FOR STARTUP OF GAS TURBINEEnsure that all the work permits taken are returned.Check that no personal is working in the GT enclosure.Check for power supply to all the motors given from MCC.Check healthiness of Fire Protection System.Switch ON the supply of MARK-VIe panel.Check for all alarms coming on the screen and acknowledge accordingly.Check for any logic forcing, if it is there inform to concerned engineer.

Come to UNIT DISPLAY MENU on MARK-V and RESET the Unit by executing the command.Switch ON seal air fan and open its damper towards diverter damper.Check the oil level at Turning gear motor gear and Booster compressor casingPut the machine in ON COOLDOWN mode. AOP and Turning gear Operation will come in service.Check for lube oil flow to each bearing; lube oil header pressure (1.8 kg/cm2), check for any leakage during oil circulation and check for rotation of the shaft continuously at 3 RPM. Check the vapour mist fan for its normal operation.Check AUTO start of EOP by stopping the AOP. Note down the Lube oil header pressure (1.8 kg/cm2).Check AUTO start of EOP by stopping the AOP. Note down the Lube oil header pressure (1.8 kg/cm2).

Again start AOP and normalize the system. Charge cooling water to lube oil cooler and to flame detectors/ Turbine aft legsKeep the machine on Turning Gear for at least 12hrs. Before CRANK/FSNL.Check at HSD/NAPH day tank all the concerned valves are in opened conditions. For HSD tank suction valve to forwarding skid, short & long recirculation valves, centrifuge inlet & outlet valves should be in opened condition.

Run the HSD centrifuge at least for 4hrs. in a shift.

Receive Raw HSD if tank level is below 40% by opening its receiving valve & coordinate with UCR. Fill the Clean HSD day tanks max. up to 90% as HSD is the back up fuel and need in emergency during fuel changeover.

Check all the valves on suction, discharge and recirculation lines of liquid fuel forwarding pump, it should be in opened condition, check all pressure & temperature gauges on local panel.Check at fine filter skid for opening of all necessary valves( CV inlet & outlet and long recirculation valves).Check all the drains before starting the pump, it should be in closed condition.Start the forwarding pump from DCS and maintain pump discharge pressure 7 -kg/cm2 and CV outlet pressure 4 kg/cm2 by giving set point.

Check for DP of both fine filters, if it is more than 1.5 kg/cm2 then changeover to stand by filterCheck for AUTO start of standby forwarding fuel pump.Start DMCW pump and check its discharge pressure, maintain 3.5 4.0 kg/cm2.Check for AUTO start of DMCW pump in case of either of the pump stops.Open the liquid fuel manual isolation valve, which is just before Stop Valve.Check the IR value of starting motor. Ensure the breaker is tested in Test position and put it in service position and its spring is Charged.Start the seal air fan of diverter damper and ensure that diverter damper is opened towards bypass stack.At this point of time there should be good communication between the startup engineer and the observer at the machine. Be careful not to use radio transmitters (walkie-talkie sets) too close to speedtronic panels.

Execute MASTER RESET and acknowledge/reset all alarms in Alarm Display.Select AUTO mode on MARK-VIe panel and give START command.CRANK HT motor starts and will run on 750 RPM speed for 1 minutes for warm-up and then cranking starts i.e. 10% speed is attained, purging is done for 2 minutes at this speed.Check OFF Base lube oil system, its pressure in supply & return line, oil tank level & temperature, charge CW to its oil cooler if line temperature goes beyond 50 0C. maintain lube oil temperature 45 to 50 0C.

After purging time completes firing starts, ensure the flame indication on MARK-VIe is established. Check that false start drain solenoid is closed & ensure that there is no gas coming out from the drain and Check for spark plug retracting at around 80% speed. If they do not do, pull them out manually because, the tip, which is spot-welded, may come out and damage the turbine blades.

Check DP of HP filter which is after Warren pump inside the GT skid, it shouldnt be more than 1 kg/cm2

Trip immediately in case of any abnormality. If machine trips ensure that AOP starts and Turning Gear operation comes automatically after zero speed.Record fuel nozzle pressure with the help of selector valve downstream of flow divider.Ensure normal burning of all combustors within short period after initial firing. This can be noticed by the more or less equal temperatures in all the exhaust thermocouples.Ensure that there are no leaks.Observe for a gradual rise in exhaust temperatures up to about 480 0C. Check that rapid rises or surges or a drop in exhaust temperature are not occurring.Check that all exhaust & wheel space thermocouples indicate a raise in temperature.

Check for any rubs on machine or unusual noise.Check for starting means shut down: Generally occurs at 60% speed (14HA). Clutch disengages and starting device goes to cool down cycle and after 15 minutes it stops, if it does not stops the Motor manually .Check the main lube oil pump takes over at about 60% speed and aux. Lube oil pump stops after pressure is build up at 95% speed.Check that compressor bleed valves are closed.At FULL SPEED NO LOAD check the following check Lube oil pressure and temperature at all the brg., Brg. Drain temperatures, Uniformity in exhaust temperatures records the spread, Leaks in turbine compartment, Vibration on all bearings, All wheel space temperatures, FSR value of fuel system stability.

Atomizing air temperatures and pressure after pre cooler, maintain its temp. at 107 deg c through VTR-1.Position of compressor bleeds valves, Hydraulic oil pressure with main pump in line, Check for fuel system stability at FSNL. The speed of the machine should not vary bearings. Check brg. Header temperatures and adjust lube cooling water control (VTR 1). The ideal lube oil header temperature is from 42o C to 54o C.Record all field parameters at FSNL.Ensure that Starting HT motor breaker is kept in Test position after attaining FSNL successfully.

Give clearance for synchronization/loading the machine. Naphtha fuel changeover Procedure: Ensure that electrical load on GT is at least 5-10 MW. Start and line up the pumps as per the procedure adopted for HSD pumps. Maintain naphtha pressure after the CV 4.5 to 5 kg/cm2 . Check Hi-Tech level in the tank, it should not be below 20 cm level. Start one hi-tech pump and keep the other one in AUTO. Now fuel change over may be done. Select Naphtha in FUEL SELECT and execute the command. In case GT trips ensure that it is in ON COOLDOWN Mode & see that AOP starts in AUTO and machine comes on Turning Gear after zero speed is reached. In case GT trips while running in Naphtha fuel, then before restarting the machine purging of the fuel line with HSD is necessary. Click EXIT on CRT and then click Naphtha Purging Display and follow the procedure of Naphtha purging as displayed on the screen. Before purging ask the field operator to open all the 10 nos. of naphtha purge drain valves and ensure that all this drains are closed fully after completion of purging, then select AUTO in MASTER SELECT on Main Display Unit.

Emergency Shut Down Protective Emergency Shut DownIn case GT trips on Protection this leads to shuts of the Fuel immediately by closing Fuel Stop ValvesManual Emergency Stop to be used JudiciouslyEmergency Push Buttons are Provided on-Mark VIe Panel/Co2 Control panel

PROTECTIONS

PROTECTIVE STATUS TRIP (L4PST): PRE-IGNITION TRIP (L4PRET):POST-IGNITION TRIP (L4POST):STARTING MEANS TRIP (L3SMT):IGV TROUBLE TRIP (L4IGVT): L86TXT: EXHAUST OVER TEMPERATURE TRIPL86TFB: EXHAUST THERMOCOUPLE OPEN TRIPL30SPT: HIGH EXHAUST TEMP SPREAD (L30 SPT)L28FDT: LOSS OF FLAME TRIPL39VT: VIBRATION HIGH TRIP (FIRIED SHUTDOWN)

PROTECTIONS

L12H: ELECTRICAL OVER SPEED TRIP-HPL63ETX: HIGH EXHAUST PRESSURE TRIP (2oo3 LOGIC)L63TFH: INLET AIR FILTER DP HIGH FIRED SHUTDOWN (2oo3 LOGIC)L63QT: LOW LUBE OIL PRESSURE TRIP. (2oo3 LOGIC)L26QT: LUBE OIL HEADER TEMPERATURE HIGH TRIP(2oo3 LOGIC)L63QT: LOW TRIP OIL PRESSURE TRIP. (2oo3 LOGIC)L90TKL: EXHAUST FRAME COOLING AIR PRESSURE LOW (2oo2 LOGIC)

PROTECTIONS

L86CBT: COMPRESSOR BLEED VALVE TROUBLE TRIPL4IGVT: IGV CONTROL TROUBLE TRIPL2SFT: START UP FUEL FLOW EXCESSIVE TRIPL3SMT: STARTING DEVICE TRIPL63FLZ: LIQUID FUEL PR. LOW (2oo3 LOGIC)LOAD COUPLING COMPARTMENT TEMPERATURE HIGH

98

Thank YouThe lube oil system meets the lubrication requirements of the gas turbine and performs cooling of various parts by absorption of heat load. The lube oil is circulated through the following turbine parts

Lube oil from the GT bearing header is used for trip functions (abnormal & emergency shutdown of the turbine) and normal start-up/shutdown thus the oil is called Trip oil.

The trip oil is supplied to the inlet guide vane trip device 20TV-1, and to the GT fuel stop valve arrangement 20 FL-1. The turbine shutdown initiated by the trip system occurs due to the depressurisation of trip oil header, which is caused by draining of oil from the system. When oil in the trip oil line is dumped, the central pressure acting on the fuel stop valve by the hydraulic oil is relieved and in turn the valve gets close by spring action. In the absence of Trip Oil pressure IGV opening also falls to minimum position.The liquid fuel system provides fuel oil to the gas turbine in response to the speed and load demands and within temperature limitations of the turbine.Fuel is supplied at a positive pressure through the primary filter and the stop valve to the on base fuel pump inlet by the fuel forwarding system.

The fuel pump is a positive displacement pump with a bypass arrangement.The servo valve controls the bypass valve stroke according to the difference between the requirement and the sensed flow & accordingly bypass valve closed to increase fuel flow to turbine or vice-versa.The Fuel oil flow to turbine is proportional to flow divider speed hence the fuel flow is sensed by the magnetic pickups 77FD 1.2 and 3 which are mounted on the flow divider. This flow gives a feed back to bypass valve servo system. The purpose of the flow divider is to equally divide the fuel oil to each of the fuel nozzles of the turbine. The flow divider consists of

a series of small positive displacement gear pumps. The pumps are driven by fuel pressure at the inlet of the gears of each pump; and this equally divides fuel flow. The selector valve pressure gauge assembly is provided to monitor the fuel pressure of individual nozzle inlet line. The position of the selector valve determines the nozzles pressure of the selected line.

The purge air system is necessary to prevent the accumulation of oil fuel in the oil fuel nozzle passage and fouling of nozzles during the gas fuel operation as a result of oil fuel cooking thus keeping the oil fuel nozzles clean and ready for oil fuel operation.

Atomizing air is required to break the fuel jet coming out of the fuel nozzle into a fine mist by impinging the air on it & this helps in the combustion of the fuel at an increased efficiency.

The ventilating capabilities have been incorporated into the turbine accessory & Load Tunnel compartments with each using thermally insulated side panels and roof.

Gravity operated dampers are used in the system to automatically provide a tight enclosure when the fire protection system is activated.

The gravity closing outlet dampers are normally held open by fire extinguishing agent pressure operated latches, which must be manually reset after damper release.

When the agent is discharged, pressure on the latch forces a lever, which release the latch allowing the damper to close.