Dadri Stage-1 Start up Write-up

 

SOP to avoid unit disturbance/tripping during litup/turbine rolling/unit synchronization

1.    APH oil carryover probe to be checked hourly during light up. Oil gun having poor flame to be removed. APH soot blowing to  continue till oil guns in service. CBD to be opened after boiler litup and closed as per chemistry clearance. SCAPH charging &Dearator heating / pegging to be done . Condensate dumping to be done.

2.    Fire personnel should be called before lit up.

3.    Economizer recirculation valve kept open till load raised more than 10%.

4.     Raise PA header pressure slowly to avoid rupturing of NMEJ.

5.    APH flue gas to be charged slowly after air charging.

6.    Both TDBFP should be rolled before turbine rolling.

7.    Turbine should be rolled as per X1-X7 rolling criteria.

8.    MS silica to be recorded before turbine rolling (Inform Chemistry  to check sample for checking silica after HP/LP bypass charging).

9.    HP/IP trimming device kept ON (normal).

10.  Turbine speed/load signal should be healthy.

11.  Keep all MAL drains open.

12.  DCLOP & DC SOP trial should be taken before rolling.

13.  CRH NRV status (ON/OFF) should be healthy before rolling.

14.  SLC of lube oil system, JOP, barring gear valve, HPCF system, stator water& seal oil system kept ON.

15.  Monitor TG Lube oil filter choking before rolling.

16.  TG lubeoil ,HPCF, H2 cooler & PSW cooler controller kept in auto.

17.  All standby equipment to be kept in auto.

18.  MS / RH pressure to maintained as per casing temperature & type of start up.

19.  All TG parameters to be seen before rolling of turbine including MAL drain temperatures.

20.  Turbine throttle pressure to set at zero before turbine rolling

21.  TSE margin to be monitored and have sufficient margin during rolling & unit loading.

22.  Turbine stop valve gagging should be removed and EHTC oil supply kept normal. Keep speeder gear 100%.

23.  TG luboil  temperature to be maintained at 45 degree.

24.  TSI parameters & TG bearing temperatures  to be monitored.

25.  TG gland seal pressure (200-250 mmwc) & temperature (> 280 degree) to be maintained.

26.  DN/dt to be maintained close to 600rpm/min²during rolling.

27.  PR (max ) to be set at 10% of load and raise after unit synchronization andon seeing turbine protection inputs.

28.  Monitor closing/stopping of barring gear valve/JOP/AOP as per logic.

29.  GT oil pump running status to be confirmedfrom local after excitation made ON.

30.  HPT exhaust temperature to be monitored at 3000 rpm.

31.  GRP relay to reset at 3000 rpm. GCB isolator to be closed and kept in remote.Switchyard person to inform before rolling & synchronization.

32.  Unit synchronization should be done through auto synchronizer.

33.  Block load(20 Mw for stage-I & 50 MW for stage-2) to be raised as quickly as possible. Unit control to be shifted from speed control to load control and speed reference should start tracking actual speed .

34.  Ensure GCB ON status should appear after unit synchronization.

35.  HP/IP control valve status to be monitored.

36.  HP/IP top bottom DT to be monitored.

37.  Try to keep IPCV full open during load raising

38.  Load to be restrict less than 70 MW , If turbine extended protection value are in tripping range.

39.  MAL drains to be closed as per ATRS criteria.

40.  HP/LP bypass to be kept in manual after turbine rolling and valve to be closedafter watching change in boiler pressure to avoid load hunting at part load during warm rolling. Bypass tobe kept in auto after load stabilization.

41.  Generator seal oil temperature to be monitored.

42.  Generator temperatures to be monitored during load raising

43.  Cold gas ,stator water,  & exciter air temperature to be monitored.

44.  Stator water conductivity to be monitored.

45.  LLD level to be monitored during startup.

46.  Generator voltage to be maintained during load raising.

47.  H2 pressure & seal oil DP to be monitored

48.  Condenser vacuum to be monitored during load raising.

49.  Turbine extraction to be charged after proper draining.LPH/Deaerator extraction to be charged below 100 MW & HPH extraction at 150 MW.

50.  Boiler pressure to be maintained as per load.

51.  Feed water low range to high range changeover to be done after keeping DP zero.

52.  Maintain hotwell, dearator, drum level, MS/RH steam temperature and drum pressure during load raising.

53.  Bunker outlet /Feeder inlet gate should be open.

54.  Oil gun to be removed afterboiler healthy flame.

55.  All ESP flue gas gates to be opened after 02 mills in service. (since lit up is done with ESP two pass charged).

56.  ESP fields to be charged after oil gun removal.

57.  Coal feeding to be done slowly to avoid boiler pressure & temperature rise abruptly.

58.  Maintain furnace pressure, PA header pressure, O2 %  during load raising.

59.  Maintenance personnel should be present during load raising/unit stabilization

60.  Unit protection to be normalized as early as possible.

61.  Observe MOT/HPCF/TDBFP oil levels