P CHANDANKHEDEDy. Supdt, Operation

TG ROLLING PREPARATION

1. VACUUM PULLING & SEAL STEAM CHARGING

2. MS LINE WARMING & CHARGING3. HP BYPASS CHARGING4. LPBYPASS CHARGING

VACUUM PULLING

• ENSURE DRAIN BEFORE CRH NRV TO SDFT CRHV 101 , MS/HRH STRAINER DRAINS (to remove impurities) TO SDFT(MSV109,110 & HRHV 105,106) ARE OPEN.

• STATRT VACUUM P/P 1 RECIRCULATION P/P & OBSERVE THAT SEAL WATER FLOW (remember the water ring around impeller!) IS ADEQUATE,START VACUUM P/P 1.

• AIR IV V/V OPENS ON INTERLOCK & VAC STARTS BUILDINGUP.

• START 2ND VAC P/P FOR HOGGING OPERATION FOLLOWING THE SAME PROCEDURE & THAT CAN BE STOPPED DURING HOLDING OPERATION AFTER VAC BUILDS UPTO -0.90 Ksc .

SEAL STEAM CHARGING

• ENSURE OPENING OF SEAL STEAM HEADER DRAIN MAL 81 & WARM UP DRAIN V/V BEFORE SUPPLY HEADER.

• ENSURE SEAL STEAM SUPPLY HEADER IS ISOLATED.• CRACK CHARGE SEAL STEAM MANUAL ISOL V/V AT

8.5 M & PRDS SOURCE MOTORIZED V/V ASV-67 AT 17.

• OBSERVE THAT STEAM TEMP STARTS RISING & As AUX STEAM TEMP BEFORE SUPPLY HEADER INCREASES > 190 0 C , GRADUALLY FULL OPEN THE MAN & MOT V/Vs & CHARGE HEADER UPTO WARM UP DRAIN V/V.

SEAL STEAM CHARGING

• CRACK OPEN SUPPLY HEADER BYPASS V/V, SEAL STEAM HEADER PRESS STARTS BUILDING OPEN GSC SAFETY V/V TO ATMOSPHERE.

• START ONE GSC VAPOUR EXTRACTOR & ENSURE OPENING OF ITS I/L TO GSC.

• OPEN SEAL STEAM SUPPLY V/V TO GSC, SEAL STEAM SAFETY V/V CLOSES ON INTERLOCK.

• OPEN SUPPLY & LEAK OFF HEADER MAIN LINE V/VS. PUT SEAL STEAM HEADER PRESS CONTROL ON AUTO & MAINTAIN HEADER 200 MMWCL.

Stage 2 or 3

MS LINE WARM UP & CHARGING

• AT BOILER DRUM PRESS APPROX 2 to 3 Ksc, ENSURE DRUM VENTS & SH VENTS ARE CLOSED.

• AT APPROX 8 TO 10 Ksc ENSURE SH DRAINS ARE CLOSED.

• CONDENSER VAC IS PULLED.• ENSURE MS DRAINS TO IBD TANK BEFORE BOILER

STOP V/Vs (MSV 101 & MSV 102) ARE OPEN.

MS LINE WARM UP & CHARGING

• ENSURE MS STRAINER DRAIN V/Vs MSV105 & MSV106 TO UFT (TILL BYPASS IS NOT CHARGED) & HPBP DRAINS BEFORE BP V/Vs ( BPV 101 & BPV 102) TO UFT ARE OPEN.

• OPEN STOP V/VS EQUALIZING LI NE MOT V/Vs MSV3 & MSV4 & THEN CRACK CHARGE INCHING V/Vs MSV5 & MSV6 & OBSERVE MS TEMP BEFORE ESV IS RISING, GRADUALLY INCREASE INCHING V/Vs OPENING TO FULL & THEN OPEN MSV1 & MSV2. AFTRE MSV1 & MSV2 ARE FULL OPEN CLOSE THEIR EQUALISING LINE V/Vs.

HP BYPASS CHARGING

• Drain v/vs BPV 101 & BPV 102 to UFT of BP1 & BP2 warm up line are open & also ensure opening of bypass spray block v/v(BD v/v) man isolating v/v.

• Open BP1 & BP2 line warm up v/vs BPV-3,BPV-4 & close their drains to UFT.

• Open BP1 & BP2 5% manually & check HPBP D/S temp is rising & also temp is maintained by spray control v/vs BPE1 & BPE2.

• Raise boiler firing by increasing HFO pr. & close SH start up vents.

LP BYPASS CHARGING

• Open LPT exh hood spray isolation v/v & charge LPBP warm up line drains.

• LPBP spray from CEP is lined up. • LPBP both temp dependent solenoid v/vs are reset.• Keep LPBP controller in manual mode & give command to

controller until water injection v/v 1 & 3 open, then both bypass stop v/vs & control v/vs open in sequence. Regulate CVs opening & maintain HRH pr approx 4-6 ksc.

• IF LPBP D/S flow increases > 45%, check & ensure opening of second stage water injection v/vs.

• LPBP operation with ACI: it automatically opens LPBP CVs to 25% & holds it until HRH pr. reaches 12 Ksc, then ACI switches off.

TYPES OF TG ROLLING

1.Cold Start up – If HPC metal Tempr<1500C.

2.Warm start up – If HPC metal tempr betwn 150 to 3500C.

3.Hot start up – If HPC metal temp > 3500C.

HPC METAL TEMP IS THE DEFINING CRITERIA FOR DIFFERENT TYPES OF ROLLING

PRE-REQUISITES FOR TG ROLLING• Turbo-Generator on Barring gear with all Turbo

supervisory parameters are normal. • Boiler is lighted up condition with one /two oil

elevations are I/s.• VACUUM PULLED(S. STEAM PR./TEMP 0.02 KSC/>220

DEG C) & GLAND STEAM PR CONTROL ON AUTO.• HP-LP Bypass is in charged condition.• Boiler load index is 95 to 100 T/Hr.• Steam parameter are ready for rolling.

M.S. Pr. 35-40 Ksc. HRH Pr. 6-12 Ksc. M.S. and HRH Temp. – 320 to 3500C

START UP CONSIDERATIONS• During the startup the Turbine is subjected to “Non-

Steady state operation”.• This covers the operating condn where Speed, steam Pressure

and temperature change with time.• Under these condn turbine components which are exposed to

temperature changes subjected to thermal stress and expansion.

• For turbine life point of view, it is very much necessary to limit the extent of these temperature changes.

• To take care of the above factor the operator has to follow the recommendations from Turbine Stress Evaluator and start the Rolling procedure by following Criteria curves X1 to X7 right from the beginning.

TURBINE STRESS EVALUATOR

• The Turbine is equipped with the TSE which provides adequate guidance to the operator by indicating temp margins and Load margins.

• These Margins have been derived on the basis of Actual Thermal Stress and Material Fatigue.

• Frequent and substantial departures from criteria curves and TSE Indication can result

a. Reduction in total life of Turbineb. Non permissible deformation. c. Damage of Turbine Components

RESETTING THE TURBINE WHY?BEFORE STARTING ROLLING WITH ATRS TURBINE NEEDS

TO BE RESETTED AS DURING TURBINE TRIP DUE TO ELECTRICAL/ MECHANICAL PROTECTION TRIP OIL DRAINS

When the Turbine trips due to Electrical or Mechanical Protection Trip oil drains quickly.

• In the absence of the Trip oil Turbine Stop and Control valves closes quickly.

• So the Trip oil is basically required for keeping the ESVs and IVs in open condition and getting required Secondary oil pressure for opening the HPCVs and IPCVs.

• The Trip oil again can be generated again by resetting the Turbine.

KWU 500 MW TURBINE GOVERNING

RESETTING THE TURBINE • Reset the Unit Or Master Trip Relay.• Bring the Starting Device to Zero. • Unit or Master Trip Relay can be reset By

1.Resetting Boiler Master Fuel Trip Relays.2.All Generator Trip Relays Reset.

3.Turbine Electrical Protections to be Reset.• The Zero position of starting device generates

a. Start up oil and b. Aux start up oil. Aux start up oil is required to reset Trip gear.Start up oil is required for resetting ESVs and IVs.

It also ensures that the control valves opening are prevented till ESVs and IVs are opened.

RELEASE FOR SGC TURBINE START-UP

1. STARTING DEVICE AT ZERO POSITION ORANY ONE HP ESV OPEN AND ANY ONE INTCPT ESV OPEN

2. TURBINE CONTROLLER POSITION SET POINT < O% ORSTARTING DEVICE > 42 % AND STARTING DEVICE > 56 %

3. GENERATOR BREAKER OFF AND FIELD BREAKER OFFORTURBINE SPEED > 2850 RPM

4. DRAINS BEFORE HPCVs 1 & 2 (MAL 11, MAL 12) : NOT CLOSED OR

(ANY ONE HP ESV OPEN AND ANY ONE INTCPT ESV OPEN) OR (TURBINE SPEED > 300 RPM)

5. LIMIT PRESSURE MODE: ON6. POWER/LOAD CONTROL: ON 7. TG LUB OIL PRESS > 4.8 Ksc8. SYNCHRONIZER: OFF9. PROTECTION SHUTDOWN NOT INITIATED

SEQUENCE STEP –1

SGC Turbine startup sequence on COMMAND SLC DRAINS:ON

SEQUENCE STEP –2

1. SLC DRAINS: ON2. All HP & IP ESVs :CLOSED

OR STARTING DEVICE > 42% AND ESVs: OPEN

3. ALL HPCVs & ALL IPCVs: CLOSED AND CRH NRV: CLOSEDOR

STARTING DEVICE >56% AND TURBINE POSITION CONTROLLER SET POINT > 0%

4. ALL EXTRAXTION NRVs (A2, A3, A4.1, A4.2, A5) POSITION < 5 % OR

GENERATOR LOAD > 10%

COMMAND MS STRAINER DRAIN1: OPENMS STRAINER DRAIN2: OPENHRH STRAINER DRAIN1 : OPENHRH STRAINER DRAIN2 : OPEN

MONITORING TIME: 2 Secs

SEQUENCE STEP - 31. CONDENSER PRESSURE < -0.5 Ksc2. TRIP FLUID PRESSURE > 5 Ksc3. CEP DISCHARGE HEDER PRESSURE > 19 Ksc 4. SLC DRAINS: NO FAULT5. TURBINE SPEED > 15 RPM6. HPC MID TOP/BOTTOM DT > -550K AND < 550 K 7. IPC FRONT TOP/BOTTOM DT > -300K AND < 300 K 8. IPC REAR TOP/BOTTOM DT > -300K AND < 300 K 9. MS STAINER 1,2 & HRH STRAINER 1,2 DRAINS: NOT CLOSED

ORTURBINE SPEED > 300 RPM

COMMAND DRAIN BEFORE HPCV1 (MAL 11): CLOSEDRAIN BEFORE HPCV2 (MAL 12): CLOSE

MONITORING TIME: 60 Secs

SEQUENCE STEP - 41. DRAINS BEFORE HPCV 1,2 (MAL 11, MAL 12): CLOSED

ORESVs: OPEN

COMMAND :NIL

SEQUENCE STEP – 51. FLAME IN BOILER: ON2. HP CF TEMP > 500C 3. STEAM TEMP BEFORE HPBP (BP1,BP2) SUPERHEAT > 300 K

AND STEAM TEMP BEFORE LPBP 1,2 SUPERHEAT > 300 KOR

HPCV 1,2 MIDWALL TEMP < 1000 C4. DT (MS TEMP BEFORE HPBP 1,2 – HPCV 1,2 MIDWALL TEMP) > X1

5. DT (WET STEAM BEFORE HPBP 1,2 –HPCV 1,2 MIDWALL TEMP ) < X26. LUB OIL TEMP AFTER OIL COOLER > 350 C

COMMAND : Starting device raise

NOTE: CRITERION X1 & X2 SHOULD BE FULFILLED BEFORE OPENING THE HP ESVs

CRITERIA X3 (PRESSURE CRITERIA ) IS ALSO REQUIRED WHILE OPENING THE ESVs. MAX MS PRESS BEFORE ESVs, pMS = f ( TMCV50% )

IF TMCV50% > TSAT , PRESSURE CRITERIA IS NOT OBSERVED

TMCV50% = MIDWALL TEMP OF MCV1,2

TSAT = SAT STEAM TEMP BELONGING TO MS PRESSURE

X1 CURVE

STEAM TEMPERATURE BEFORE HPBP-1 & 2

100

600

600

100

500

300

200

400

300200 400 500MID

WAL

L TE

MPE

RATU

RE H

PCV-

1 &

2

SEQUENCE STEP – 61. ANY ONE ESVs: NOT CLOSED OR

STARTING DEVICE > 42 %

COMMAND NILMONITORING TIME: 30 Secs

SEQUENCE STEP – 7 1. BOTH HP ESVs: OPEN

NO COMMANDMONITORING TIME: 60 Secs

SEQUENCE STEP – 8 1. MS FLOW > 15 %

ORTURBINE SPEED > 2850 rpm

2. STEAM TEMP BEFORE HPBP 1,2 SUPERHEAT >300 K3. STEAM TEMP BEFORE LPBP 1,2 SUPERHEAT> 300 K

COMMAND : Drain before HPCV in auto

SEQUENCE STEP – 9 1. DRAIN BEFORE HPCV1,2: AUTO

ORTURBINE SPEED > 540 rpm

OR GENERATOR BREAKER: ONCOMMAND TRACKING DEVICE: ON

MONITORING TIME: 20 Secs

SEQUENCE STEP – 10 1. TRACKING DEVICE: ON2. BOTH INTCPT ESVs: OPEN

COMMAND : Speeder gear raise ( Condition : Turbine speed <2800 rpm AND Speeder gear

<100% )

SEQUENCE STEP – 11 1. DRAINS: NO FAULT2. GLAND STEAM PRESS CONTROL: AUTO3. SPEEDER GEAR > 100%4. LUB OIL TEMP CONTROL: AUTO5. GENERATOR CONDITIONS: FULFILLED6. ANY ONE VAPOUR EXTRACTOR: ON

COMMAND : Power set point raise GENERATOR CONDITIONS FULFILLED

1. COLD GAS TEMP CONTROL: AUTO2. H2 PURITY IN AIR > 94 % 3. H2 CASING PRESS > 3 Ksc 4. SEAL OIL DPAIR(TE)-H2 SIDE > 0.9 Ksc 5. SEAL OIL DPAIR(EE)-H2 SIDE > 0.9 Ksc 6. SEAL OIL PRESS BEHIND PUMP H2 SIDE > 7 Ksc7. SEAL OIL PRE-CHAMBER TE LEVEL < MAX

GENERATOR CONDITIONS CONTINUED…

8. SEAL OIL PRE-CHAMBER EE LEVEL < MAX 9. LIQUID IN GENERATOR TE < MAX10. LIQUID IN GENERATOR CENTRE< MAX11. LIQUID IN GENERATOR LEAD BOTTOM 1 &2 < MAX12. ANY ONE AIR SIDE AC SEAL OIL PUMP: ON 13. H2 SEAL OIL PUMP: ON 14. AIR SIDE DC SEAL OIL PUMP VOLTAGE: PRESENT15. PW TEMP CONTROL: AUTO16. PW CONDUCTIVITY <1 mho 17. ANY ONE GENERATOR BEARING CHAMBER FAN: ON 18. ANY ONE PW PUMP: ON 19. PRESS AFTER PW PUMP >5 Ksc

5. DT (HRH STEAM TEMP BEFORE LPBP – MEAN TEMP IPCASING TIPT50%)> X5 AND RH STEAM TEMP BEFORE LPBP > 4800C

ORTURBINE SPEED > 2850 RPM

6. DRAIN BEFORE HPCV 1 & 2: NOT CLOSEDOR

TURBINE SPEED > 2850 RPM 7. POWER SET POINT > 10% 8. CONDENSER PRESSURE < -0.8 KscCOMMAND TURBINE SPEED SET POINT : RAISE

SEQUENCE STEP – 121. GENERATOR CONDITIONS FULFILLED2. STEAM PRESS BEFORE HP ESVs SUPERHEAT > X3 3. DT (STEAM TEMP BEFORE HP ESV 1,2 -HP CASING) > X4 4. TURBINE SPEED > 15 rpm

SEQUENCE STEP – 14

TURBINE SPEED > 300 RPM COMMAND : MS strainer 1 drain close

MS strainer 2 drain closeHRH strainer 1 drain closeHRH strainer 2 drain close

SEQUENCE STEP – 131. TURBINE SPEED SET POINT > 360 RPM

ORGENERTOR BREAKER: ON

COMMAND :NIL

SEQUENCE STEP – 15

1. TSE TEST PROGRAMME: BLOCKED AND SGC TURBINE STEP 14 ON DELAYED: 180 Secs

ORWALL TEMP HP CASING > 2500 C

2. TSE MARGIN > 300 K OR

TURBINE SPEED > 2850 RPM3. DT (MS TEMP BEFORE HPBP 1 & 2 – MIDWALL TEMP HP

CASING) < X64. MS STRAINER DRAINS 1 & 2: CLOSE5. HRH STRAINER DRAINS 1 & 2: CLOSE

COMMAND : Drains HPCV in manual

NOTE: 1. AFTER STEP 14 TSE MARGIN IS NOT CHECKED FURTHER IN

ATRS, AS IF STEAM TEMP IS MAINTAINED MARGINS WILL NOT DECREASE.

2. HOWEVER, TSE MARGIN EFFECT WILL BE PRESENT THROUGH EHC IF TSE INFLUENCE IS ON.

3. IF TSE INFLUENCE IS MADE OFF, SGC TURBIN BECOMES OFF THROUGH PROTECTION CIRCUIT.

4. IN CASE OF TSE FAULT SGC TURBINE WILL NOT BE OFF & LAST MARGINS ARE FROZEN UNTIL SPEED REACHES 2850 RPM.

dn/dt PROTECTIONBRINGS DOWN TURBINE SPEED TO SOAKING SPEED (360 RPM)

1. IF ATRS PROGRAMME IS MADE OFF BEFORE NR > 2850 RPM

2. IF TSE MARGIN RESTRICTS TURBINE ACCELERATION < 108 RPM/MIN THROUGH EHC.

SEQUENCE STEP - 16DRAINS BEFORE HPCV 1 & 2: MANUAL

COMMAND : Turbine Speed set point raiseDrain before HPCV 1 closeDrain before HPCV 2 close

SEQUENCE STEP – 171. TURBINE SPEED SET POINT > 3036 RPM

ORGENERATOR BREAKER : ON

COMMAND NIL

SEQUENCE STEP – 181. TURBINE SPEED SET POINT < 2950 RPM

ORGENERATOR BREAKER : ON

COMMAND:AVR in auto Field breaker ON

SEQUENCE STEP – 191. AVR: AUTO

ORGENERATOR BREAKER: ON

2. FIELD BREAKER: ONCOMMAND DRAIN BEFORE HPCV 1 & 2 : CLOSE

SEQUENCE STEP – 201. BOTH AOPs OFF TD10s 2. DT (RH STEAM TEMP BEFORE LPBP –MEAN TEMP IP SHAFT) < X7 3. H2 CASING PRESS > 3 Ksc 4. CG TEMP AFTER H2 COOLER A & B < 450 C5. CG TEMP AFTER H2 COOLER C & D < 450 C6. DRAIN BEFORE HPCV 1 & 2: CLOSE

7. ANY ONE AIR SIDE AC SEAL OIL PUPMP: ON8. BOTH AIR SIDE AC SEAL OIL PUPMP : AVAILABLE 9. PW TEMP < 500 C 10. PW FLOW THROUGH STATOR WINDING & BUSHING: NOT LOW 11. DT (PW - H2) > 10 K TD15 MIN12. CONDUCTIVITY AFTER MAIN FILTER < 2.5 mho13. EXCITER COLD AIR TEMP < 450 C

COMMAND AVR: AUTOMONITORING TIME BLOCKED

SEQUENCE STEP – 211. SGC TURBINE STEP 20 COMMAND DELAYED: 15 Secs2. AVR on AUTO3. GENERATOR VOLTAGE > 95 %

ORGENERATOR BREAKER ON AND GENERATOR LOAD > 10 %

COMMAND SYNCHRONISER: ON

SEQUENCE STEP - 221. GENERATOR BREAKER: ON

COMMAND Speed set point raise

SEQUENCE STEP - 231. WAITING TIME: 2 Secs

OR GENERATOR LOAD >10%

SEQUENCE STEP - 241. GENERATOR BREAKER: ON

2. TURBINE SPEED > 2850 RPM

END OF PROGRAMME

SYNCHRONIZATION• Generator breaker will close once permissive are matched.• Immediately raise speed reference to pick up the load on the

machine to avoid reverse power trip or low forward power trip.

• Increase the load as per TSE margin and close HP/LP bypass valves.

• Close all the drains which were opened during rolling.• Turn off the synchroscope switch to de energize

synchroscope.• Ensure that load reference set point is higher than the actual

load value.• Observed that changeover from speed controller to load

controller takes place once output of load controller is greater than that of speed controller.

SYNCHRONIZATION

• The load controller active light glows on Turbine desk. • Ensure tracking device is on.• Increase the load limiter value to about 150MW.• Check the Generator winding, exciter air, cold gas temp.,

generator stator core temp. & all TSI parameter are normal.• Raise the HP bypass pressure set point to 10KSC more than

throttle steam pr and temp. Set point to about 340C to avoid HP by pass opening on auto.

• Ensure that LP bypass stop valves and spray valves are closed.

UNIT IS SYNCHRONISED WITH LOAD CONTROLLER IN SERVICE.

LP HEATER CHARGING• Check that LPH-1 inlet/outlet valves are in open condition and

bypass valve in closed condition.• Ensure all LP heater shell vents to condenser are in open

condition.• Charge both LP heaters 2 and 3 from condensate side by

opening I/L valves and O/L valve and closing their bypass valve respectively.

• Charge LP heater-2 by opening its extraction valve. Note there is increase in level. Put its cascading drip to LP heater-1 and emergency drip to auto when the normal level is reached. Before putting to auto ensures that level set point of emergency drip is greater than normal drip set point.

• Repeat above for LP heater-3. • Ensure drain valves in extraction line closes once Ext is

charged

TO TAKE PULVERIZER INTO SERVICE

Starting of PA FAN • Can be started if flue gas outlet temperature

at Platen outlet is>300C• Check all the permissive is satisfied.• Any PRAPH is running.• Give command –check Discharge damper will

open on auto. PAPH FG & air side in/out let opens on auto.

*PA FAN IN SERVICE*

Starting Mill• Line-up from local and check all the per missives.• Start Coal mill A(bottom most available Mill)• open HAG/CAG & dampers to achieve air flow >

80T/Hr & temp>65C• Start feeder and ensure flame gets stabilized.• If pressure rises, Then increase load.• Control MS & HRH temp to get sufficient margin.• Maintain 100C more MS & HRH temp than

HPS/HPC/IPS/HPSV/HPCV.• Raise load as DC/SG. 75MW• Take another mill into service. Load 120MW.

• Maintain MST & HRH temp by BT & spray.• Take another mill into service. Pr 90 KSC & load 200MW.• Take another Mill into service. Pr 110 ksc & load 250MW.• Take another mill into service. Pr 120 Ksc & load 300MW.• Remove oil support.• Take another Mill and raise the load. Pr 130KSC & load

400MW• Take 6th Mill in to service & raise the load.Pr 170 & load

500MW.• Maintain O2 3.5%. CO less than 40.• Maintain draft on auto.(IGV & VFD both on auto)

Charge ESP when flue gas temperature at outlet of APH reaches above 100C

Steam Temperature Control• To line-up &charge super heater attemperation

system.• To line-up & charge reheater attemperation system.

Charging Of Unit Transformer• To charge unit Transformer put synchronizing key to

the breaker leading to UA/UB bus end.• Put key to check position.

• Close the breaker when in-synchronism light glows and hold it for 2sec.

• Note that the incomer breaker from SA/SB bus, is tripped.

LOAD RAISING OPERATION• If unit is in EHTC and in load control mode, load

increase command can be given from the desk (by increasing load reference)

• Pressure variation should be minimum to set throttle pressure. If throttle pressure is decreasing after giving certain load set point, increase boiler firing (by PA header pressure or by opening control damper or by taking oil guns)or decrease load set point.

• At load around 150-200 MW take feed water Hi-range in service. Now varying the BFP speed will control drum level. If the speed is put to auto , FW master will give the command to BFP speed. FW master may be put in auto if normal level is achieved.

• It is advisable to put primary air pressure control in auto to facilitate good control over firing.

Taking Second Set Of Auxiliaries

STARTING OF TDBFP• Lube oil system• Jacking Oil system• Turbine on Barring Gear• Steam charging and rolling

TO LINE UP AND TAKE HP HEATER IN SERVICE

RAISE THE LOAD TO RATED VALUE