2gt-Startup & Shutdown Procedure_10!05!2011

Evonik Energy Services (I) Private Ltd Prepared by – Arvind Patil, EESI, Hazira

GT-6FA STARTUP & SHUTDOWN PROCEDURE

Rev: 00 Date: 09.05.2011

GAS TURBINE STARTUP & SHUTDOWN PROCEDURES PRE START CHECKUP: • All MCC modules are switched ‘ON’ and are kept on ‘AUTO’ • Lube Oil Level is OK and Oil Temp. is Normal. • Select ‘Cool down ON’ and ensure that the AC Lube Oil Pumps Start and Slow roll is OK. • Start EOP and ensure that the Pressure developed is OK. • Cooling water level is OK. • Visual Inspection of Machine is OK. NORMAL START: Select “UNIT CONTROL DISPLAY / START UP” in MARK-V or MARK-VI Operator Selects “CRANK/FIRE/AUTO” Then “Execute”. Protection System checks ‘Ready to Start’ Permissive. 1. Generator Lockout Relay is reset. 2. Turbine at zero speed / on slow roll. 3. Flame is not detected in all Scanners. 4. Compressor Bleed valve is open. 5. “OFF” is not selected. 6. “IGV” is closed.



Rev: 00 Date: 09.05.2011

7. Master Protective ‘L4’ logic is reset. 8. , , & Master Protective agree. 9. Emergency Lube Oil Pump Voltage is Normal. 10. , , & Communication links are healthy. 11. Generator Breaker is open. 12. Auxiliaries are healthy and Duel System faults reset. 13. Ignition transformers/exciters supply normal. 14. Lube Oil Temp. Normal. 15. Bleed Heat System Fault / TRIP are reset. 16. Primary Purge valves are close. Then ‘READY TO START’ DISPLAYED. Operator Presses “START” then “Execute”. 9 Start counter is Incremented. 9 DC Oil Pump is started for EOP TEST. 9 Unit Start continues if pressure switch 63QE-1 senses EOP discharge pressure within 8 sec. if not, START is aborted. 9 AC Lube oil pump started, if not already started. 9 Lube oil mist eliminator started along with Lube oil Pump. 9 Barring Gear is Started ( if ‘ OFF COOL DOWN’) 9 Master Protective system energizes ( L4 ) Then “STARTING” displayed, 9 Auxiliary Hydraulic Pump started.



Rev: 00 Date: 09.05.2011

9 SFC Speed reference is set to ‘ PURGE ’ Value= LK14CX1 for Cold start (30%) = LK14CXH1 for Hot start (16%) 9 LCI is started. 9 SFC accelerates. 9 Turbine Breaks Away. 9 Exhaust Compartment (88BX) starts. Then “CRANKING” Displayed, 9 After reaching beyond 8.4% speed load compartment vent fan (88VG) started. 9 20TV IGV Solenoid is energized(if NO IGV Trip) 9 Turbine reaches cranking Speed ( about 30% speed during Cold start and about 16% speed during Hot Start) 9 ** In CCPP-II, Cranking Speed reaches is only 30%, there is no provision of Hot/ Cold Start. 9 After reaching cranking speed, turbine is purged for 7 min. 9 Speed reference to SFC is withdrawn after completion of purge. With this Unit undergoes freefalls. 9 After L14HM Dropout (below 13.5% speed), SFC reference set to firing value LK14TMF1 (14%). When L14HM pick up (above 14% speed) firing permissive is enabled. Then “FIRING” Displayed



Rev: 00 Date: 09.05.2011

Energies Gas Fuel Trip Solenoid (20 FG ) permissible for SRV & GCV Enabled

1. Fuel Stroke reference (FSR) is set to firing value. Opening of GCV is Based on this 2. Ignition Transformers/Exciters is energized and sparking of spark plug take place for the 30 sec.

No

“Failure to Ignite” Alarms appears Turbine

Flame is detected in 2 out 4 Scanner and steady for 30 sec

Yes

FSR cuts back to WARM-UP Value

Then WARM-UP Displayed, 9 WARM-UP Timers starts ( 60 Seconds) 9 Turbine compartment Vent fan (88 BT) Started 9 Fired starts counter incremented. Fired hours timer energized.



Rev: 00 Date: 09.05.2011

9 After WARM-UP completion, SFC Speed Reference set to full Speed Value (100 %).FSR is increased at predetermined rate to accelerate the turbine. Then “ACCLERATING” displayed, 9 After approx. 85% speed, IGV starts opening with increase @ 5.27DGA/% increase in Speed to the FSNL, IGV Angle=CSKGVMN1= 54 DGA. 9 After L14HP pick up (approx. 87% speed), SFC Signal is self Cut Off and the unit become self sustaining. 9 Compressor bleed valve gets close. 9 Compressor Discharge Pressure reaches from 1 bar to 7 bars. Unit reaches 100% Speed, Then “Full Speed No Load” Displayed, 9 Enables MANUAL RAISE/LOWER of Turbine speed reference to synchronize the unit. 9 If AUTO SYNCH. Permissive are OK, Generator and Line are present and above minimums, the control system will modulate FSR to bring Speed to match the station line frequency and closes the Generator breaker when phase angle is OK. 9 Depending upon the load mode selection, turbine is loaded to the reference and load maintained.



Rev: 00 Date: 09.05.2011

“SPINNING RESERVE for CCPP-I/PART LOAD/PRESELECTED LOAD/BASE LOAD” Displayed. CHECKS DURING START UP: ¾ Flame is sensed in all Flame Scanners. ¾ Exhaust Temperature are uniform and Spread is normal. ¾ Acceleration is smooth and time taken is in line with earlier values. ¾ Rise in Exhaust Temperature is uniform. ¾ Exhaust Temperature profile is OK and Spread values are within limits. ¾ Rise in Wheel Space Temperature is uniform. ¾ Vibrations are within limits and as per earlier values. ¾ Bearing Oil Drain Temperatures are normal. GAS TURBINE SHUTDOWN: SHUTDOWN OPERATIONS: Gas Turbine Shutdown can be achieved by two means. NORMAL OR FIRED SHUTDOWN EMERGENCY SHUTDOWN MANUAL EMERGENCY SHUTDOWN



Rev: 00 Date: 09.05.2011

PROTECTIVE EMERGENCY SHUTDOWN FIRED SHUTDOWN: o Normal Shutdown reduces the fuel to the Turbine in a controlled way ( Up to 20% of Speed and shuts of the fuel totally) so as to reduce the overall thermal shock to Turbine Internals o It is executed by using “STOP” Push buttons on UNIT CONTROL DISPLAY in MARK-V/ STARTUP display in MARK-VI. o This is the most preferred shutdown mode. EMERGENCY SHUTDOWN: o Shuts of the Fuel Immediately by closing the Fuel Stop Valves. o Manual Emergency Stop to be used judiciously. o Emergency Push Buttons are provided on - MARK-V/ MARK-VI Control Panels. - The Manual push lever on over speed bolt. STANDBY OPERATIONS: When the machine is not run for long time? Put the machine on Ratcheting/Barring for at least 30 min daily.



Rev: 00 Date: 09.05.2011

Crank the turbine once in a fortnight to drive away moisture. Operate the GT to FSNL once every month to avoid corrosion of turbine wheel dovetails. Daily Check Battery System, Oil levels etc.



Rev: 00 Date: 09.05.2011

Do’s and Don’ts in Shutdown, Startup and Running GT 1. Check the Evaporating cooling system parameters DP after evaporating system, Relative humidity; ambient temp and also check Air pulsating system should be in service daily. DM water to be used in evaporating cooling system. 2. Ensure all the Doors of Turbine compartment, Diffuser compartment and Load Gear Compartment to be in closed position otherwise GT will trip. Advantage of closed doors, bearings have thin casing. If doors opens continuously casing may be cooled and causes rotor rub. 3. Venting and draining of filters and line of water injection system and after water injection put in service. 4. IGV, SRV and GCV sluggishness /stroke operation manually checked in every shutdown as per earlier values. 5. Water injection Purge feed valves sluggishness/stroke operation manually checked in every shutdown. Operated as per earlier time 6. Compressor Bleed valves passing of valves /Sluggishness +/stroke operation manually in every shutdown operated as per earlier time. 7. Air inlet DP Switches, AFPCS and AFPAP impulse line flushed in every shutdown. 8. Lube oil filter to be cleaned in every shutdown and also check its oil pressure and hydraulic oil pressure as per earlier values. 9. All pumps, vent fans and blowers actual current rating to be measured weekly and change over the entire stand by drives every 15 days. 10. Turbine and Diffuser compartment DP switches checked in every shutdown. 11. Mark-V Card Inspection Inspect all PWB in each core. Verify all plug in relays are firmly connected into their sockets.



Rev: 00 Date: 09.05.2011

Check to see each card is held firmly. Check to see card identifier is on left top corner in each core. This is to ensure card orientation. 12. Mark-V card inspection using appropriate caution while replacing cards in card carriers. Avoid binding/ pinching/chafting of ribbon cables and wire hardness. 13. Verify polarity and voltage of DC/AC supplies of Mark-V 14. Energies the processors (,, & , ) one at a time while monitoring the supply. The LCC display should indicate state A4,A5,A6 or A7 and possibly with several messages in Mark-V 15. Control constants are to be verified or updated as per site control specification document. Approximation of any number or constant is strictly not allowed. Qualified Person only should update the control constants and such up dation or amendment to be avoided when the Gas Turbine is running. 16. Do not force any logic for Startup. 17. Do not attempt subsequent starts without troubleshooting if machine trips during startup. 18. Maintain AC temperature between 16 deg C min to 20 deg C max for Mark-V panel. 19. Record the TREND and ANALYZE present operation. a. Load Vs Exhaust Temperature b. Load Vs FSR c. Load VS CPD d. Load Vs Vibration. e. Load Vs Wheel space Temp. f. Load Vs IGV and load tunnel temp. g. Load Vs GCV, SRV etc h. Use all trend from MARK-V/MARK-VI to notice incipient problem.

2gt-Startup & Shutdown Procedure_10!05!2011

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