Unit Shutdown Checklist

Date : __________

Time : ___________

Reason of Tripping: ____________________________________________________________________________________________________________________

1. Unit Just Tripped / Stopped

First Up acted:

Turbine: ______________

Boiler: ______________

GRP Relays Acted: _____________

Boiler Side

S.No	Activity to be monitored	Remarks
	Both PA Fans tripped	Yes No
	All Mills Tripped	Yes No
	All Feeders Tripped	Yes No
	HFO Trip valve is closed	Yes No
	LDO trip valve is closed	Yes No
	All Scanners show NO – Flame	Yes No
	HFO/LDO Nozzle valves in closed condition	Yes No
	All Hot air gates are in closed condition	Yes No
	SH spray valves closed.	Yes No
	RH spray valves closed.	Yes No
	Burner Tilt became horizontal	Yes No
	Drum level normal.	If drum level could not be maintained, stop BCW pumps.
	PAPH outlet flue gas dampers Closed.	Yes No

Notes:

Close Boiler Stop valves if the Boiler is not going to be lighted up immediately.
If boiler trips due to either both FD fans trip or both ID fans trip, as soon as fans are ready start one set of ID/FD Fans and purge the boiler.
If Boiler forced cooling is required for any repair work on pressure parts, continue the running of ID/FD fans with around 1000 t/hr air flow along with at least one BCW pump in service. Other wise ID/FD fans can be stopped after purging the boiler.

Turbine/Generator Side

S.No	Activity to be monitored	Remarks
	All Turbine stop and control valves closed	Yes No
	GCB/Field breakers open	Yes No
	Turbine speed is coasting down	Yes No
	CRH NRV & Extraction FCNRVs closed	Yes No
	AOP came on auto < 2850 RPM	Yes No Lube oil pressure =
	Check HP evacuation valve is open	Yes No
	Condenser vacuum is Normal	Yes No
Note: If turbine trip is due to low condenser vacuum, trip boiler and close boiler stop valves & HP/LP bypass valves.
	All extraction valves closed LPH -2,3 ,D/A, HPH 5A , 5B , 6A , 6B	Yes No
	BFP C in service to maintaining Drum Level	Yes No
	TDBFPs running on Aux steam or on Turning gear.	Yes No
	HP Bypass valves in closed condition	Yes No
	HP Bypass spray line manual valve closed.	Yes No
	RH pressure should be less than 12 Ksc	If required RH can be de – pressurized by opening LP bypass
	Check all the MAL drains are open including HP Casing drain	Yes No
	Check Motorised drain in CRH line is in open condition	Yes No
	JOP started at 510 RPM	Yes No
	Gate valve gearing open at 210 RPM	Yes No
	Time taken for TG to come on barring speed from 3000 RPM to 1. Time taken to reach 540 RPM : 2. Time taken to reach 210 RPM : 3. Time taken to reach 120 RPM : 4. Time taken to reach 85 RPM : ( Vacuum Killed )	_______________ minutes _______________ minutes _______________ minutes _______________ minutes

Activities after TG came on barring

S.No	Activity to be monitored	Remarks
	Check Hot well / De-aerator levels Aux Steam enters the system through seal steam.	Hotwell level has the tendency to rise indefinitely - monitor the level continuously. Close Hotwell make up isolating valve Use deaerator overflow if deaerator level rises due to control valves passing.
	One CW Pump Stopped	Yes No
	Switch off all ESP fields after 02 Hrs of Boiler trip	Yes No
	Vacuum can be killed if immediate startup is not planned. Before killing vacuum ensure, 1. Boiler stop valves are closed. 2. MS, CRH and HRH pressures are zero else use HP/LP bypass for depressurization. 3. Close seal steam warm-up drain, drain valves before AS-1 and AS-3 of TDBFP A&B.	Monitor the Turbine speed if vacuum is killed
	Check for any oil leakages or fire or smoke at Turbine bearings / HP Bypass / Seal steam valves	Yes No
	Manual isolating valves at Oil elevations closed	Yes No
	Open GCB isolator opened if the unit will remain shut down for more than 02 hrs	Yes No

Remarks : ____________________________________________________________________________________________________________________________________________________________

Unit Start – Up Checklist

Date: ________

Time: ________

Just Before maintenance give clearance for boiler light up

Boiler Side

S.No	Activity to be monitored	Remarks
1.	Ensure that isolations of pending permits do not affect unit startup.	Yes No
2.	At least one CW pump in service.	Yes No
3.	Two ACW pumps in service, Standby in auto.	Yes No
4.	SGECW pump in service. Standby available. Tank level normal.	Yes No
5.	Cooling water is Charged for all the auxiliaries like ID , FD , PA , Mills & APHs	Yes No
6.	Lube oil system for ID, FD, PA, APH and Mill in service and filters are clean.	Yes No
7.	Check APHs for actual rotation from local & air motor is in normalized condition	Yes No
8.	Scanner air fan is running and header Pr. Normal - > 250 mm	Yes No
9.	Primary and secondary SCAPH I/L and O/L dampers open, bypass closed	Yes No
10.	PAPH Gas O/L dampers closed.	Yes No
11.	Available ESP passes I/L and O/L Gates open, ACP in service, Fields ready to be taken into service.	Yes No
12.	Burner Tilt Horizontal	Yes No
13.	Boiler expansion indicating rods are in position	Yes No
14.	Instrument & Service air pressures are adequate	Yes No
15.	Aux. PRDS Unit header charged from Station Header, Pressure and Temperature o.k.	Yes No
16.	Bottom/Fly ash evacuation system ready.	Yes No
17.	Trough seal over flow is OK	Yes No
18.	Ensure all the manholes and peep holes of the Boiler are closed.	Yes No
19.	HFO/LDO trip valves in closed condition	Yes No
20.	HFO, LDO, Atomising steam and Air manual isolating valves are open.	Yes No
21.	Ensure short recirculation valve is open.	Yes No
22.	Available oil guns properly clamped. Fuel oil, Atomising Steam/Air corner manual valves are open.	Yes No
23.	Raise the HFO temp>120⁰C	Yes No
24.	Ensure Tracing steam is in normalized condition and lines at oil elevations are hot.	Yes No
25.	Available mills are kept normalized electrically and mechanically	Yes No
26.	Pulveriser discharge valves, Burner isolation gates are open	Yes No
27.	Boiler corners fire protection system is in service	Yes No
If drum pressure is less than 2 kg/cm² before light up
28.	Ensure SH header drain valves and master drain valve are open.	Yes No
29.	SH/Drum vent valves are open.	Yes No
30.	Boiler shutoff valves are closed	Yes No
31.	SH startup vents are open.	Yes No
If drum pressure is >2 kg/cm²
32.	SH startup vents open or Condenser vacuum available for charging HP/LP bypass system immediately after lightup.	Yes No
33.	Boiler filled up to normal drum level.	Yes No
34.	Economiser Recirculation valve open	Yes No
35.	At least one BCW pump (preferably two pumps) in service.	Yes No
36.	SH , RH spray valves normalized	Yes No
37.	MS, CBD, SH sampling points are normalized.	Yes No
38.	CBD manual valves at Drum and EF elevation are kept open	Yes No
39.	Ensure HP Bypass spray manual valve is kept closed.	Yes No
40.	All available ERVs motorized isolating valves are in open condition	Yes No
41.	APH soot blowing steam lined up from Aux steam.	Yes No
42.	APH – oil carryover probe is kept after cleaning / Lights are glowing in cold end air side	Yes No
43.	SCAPH isolating valves are kept open	Yes No

TG Side

S.No	Activity to be monitored	Remarks
	TG on barring and Turbine lube oil pressure is O.K.	Yes No Lube Oil Pressure =
	Lube oil filter DP Noraml.	Yes No
	SLCs of Turbine lube/Jacking oil pumps, turning gear ON	Yes No
	SLC of ASOPs, DCSOP and H₂SOP ON	Yes No
	Condenser CW passes are charged and ACW system in service.	Yes No
	Both CW pumps are in service.	Yes No
	Two TG ECW pumps are in service. Tank level normal	Yes No
	MOT / FRF / BFPs – oil levels are OK	Yes No
	MOT / TDBFP A / B ; Control Fluid ; SOST vapor exhausters are in service	Yes No
	MOT , C.F. , BFPs , H₂Gas , Exciter , Primary water , Seal oil coolers in charged condition	Yes No
	One HPCF pump in service with standby available.	Yes No
	HPCF regeneration circuit in service.	Yes No
	SLC HPCF pumps and heaters ON.	Yes No
	Any one primary water pump in service with standby available.	Yes No
	SLC of PW pumps ON.	Yes No
	PW tank level normal	Yes No
	PW winding and bushing flows are normal	Yes No
	Primary water alkalyser is in service & conductivity normal.	Yes No
	Gen casing H₂ pressure >3.3 kg/cm² and purity >99%	Yes No
	H₂Driers are in service.	Yes No
	Sufficient H₂ and CO₂ cylinders are available in stock.	Yes No
	Lube oil, HPCF, PW and H₂ gas temp controllers are on auto.	Yes No
	Generator LLDs are clear.	Yes No
	Governing rack is in normalized condition with EHC isolating valves in open condition	Yes No
	On EHTC Mimic Speed SP < Turning gear speed EHTC output is -10% Load controller ON Throttle Pressure SP around 50 kg/cm²	Yes No
	Check all the manual isolating valves provided in the turbine side drains are in open condition	Yes No
	No “MCC disturbance” in MAL valves, MS/HRH strainer drain valves, CRH NRV drain valve, HP/LP bypasses warm-up drain valves.	Yes No
	HP evacuation valve open	Yes No
	Available BFPs are kept normalized	Yes No
	Turbine Stop and control valves – gags in removed condition ( C.F. valves are normalized )	Yes No
	Check all the TG bearings return oil flow / vacuum O.K.	Yes No
	All DM Make up pumps available including CST pumps	Yes No
	Both CPUs are in service	Yes No
	GT back charged, coolers in service, ensured locally	Yes No
	UT A & B coolers in service.	Yes No
	11 kv buses 5UA and 5UB charged from UT A & B.	Yes No
	Supply to all the HT / LT SWGRs available	Yes No
	LP dosing pumps ready to be run along with BFP	Yes No
	Fire protection systems for transformers, Oil tanks and cable galleries are in service	Yes No
	Written clearance from PP / RM / C&I / TM / AHM / EM in communication register	Yes No

Boiler lighted up and HP/LP bypass charged

S.No	Activity To be Monitored	Remarks
	APH Soot blowing is in progress	Yes No
	Sec SCAPH is kept in service	Yes No
	Air and Flue gas out let temperatures of APHs are normal	Yes No
4.	Drum metal temperatures Top / Bottom
5.	Seal steam pressure controller in auto and supply temperature >250^oC	Yes No
6.	De-aerator Pegging steam charged – after any BFP is kept in service & Pressure and Temperatures are OK –3.5 Ksc & >120^oC	Yes No
	No change in turbine speed after charging HP/LP bypass	Yes No
	Check - Load reference should be at 55 MW as per logic on auto while rolling through ATRS	Yes No
	PR_Max ( load limiter ) at > 250MW	Yes No
	CBD is kept open	Yes No
	Check Hotwell , Dearator ,Drum levels , HFO / LDO pressures	Yes No
	HP / LP dosing as per chemist advice	Yes No
	Both the vacuum pumps are in service	Yes No
	Check for any oil leakages or fire or smoke at Turbine bearings / HP Bypass / Seal steam valves	Yes No
	Open HP Bypass spray manual valve just before taking 1^st mill in service	Yes No
	Check seal air fan took start on auto along with PA Fan and DP >500mmwcl	Yes No
	ESP fields are put in service after 1^st mill is put in service	Yes No
	GRP relays reset	Yes No
	Note down D/A , Hotwel levels	Yes No
	Note down condenser Vacuum
	Written clearance obtained from Chemist for Turbine rolling	Yes No
	Keep all the Turbine side drains open before starting Turbine rolling	Yes No

4. Turbine Rolled upto 3000 rpm

S.No	Activity To be Monitored	Remarks
	Gate valve gearing closed at Turbine speed > 240 RPM	Yes No
	JOP stopped at Turbine speed > 540RPM	Yes No
	HP evacuation valve should close at Turbine speed > 2850 RPM	Yes No
	AOP stopped at turbine speed >2850 rpm and lube oil pressure normal.	Yes No
	Both sets of ID/FD fans in service before synchronisation	Yes No
	Check HP Bypass / seal steam area for any oil spillage / Fire	Yes No
	One TDBFP rolled and running on recirculation	Yes No

2. Unit Synchronised

S.No	Activity To be Monitored	Remarks
	Excitation is on AUTO	Yes No
	Tracking device in auto and tracking EHC	Yes No
	Load controller active, raise set point if required.	Yes No
	Ensure speed set point is tracking actual speed by 15 rpm after load controller takes over.	Yes No
	SLC Drains on auto.	Yes No
	HP/LP bypass closed.	Yes No
	All the heaters LPH 2 , 3 , D/A and extraction valve to TDBFPs are charged	Yes No
	LPH-2&3 level controls on auto	Yes No
	Note down D/A , Hotwell levels	Yes No
	Note down condenser Vacuum
	Keep the CRH header drain open for some more time.	Yes No
	All the Turbine side drains (other than extraction 5&6) are closed	Yes No
	HP Turbine Top / Bottom DT< 10 ^oC	Yes No
	IP Front / Rear Top / Bottom DT less than 10^oC	Yes No
	Gland Seal steam controller on auto	Yes No
	Check TSE Margins > 10^oK always	Yes No
	Check HP Exhaust temperature	Yes No
	Check RH pressure corresponding with the load	Yes No
	Furnace pressure controller, PA header pressure controller on auto.	Yes No

After crossing 60% load

S.No	Activity To be Monitored	Remarks
1.	HP heaters are charged, Level controllers on auto.	Yes No
2.	Ext-5 &6 drains closed	Yes No
3.	Check BC, DE flame scanners for healthy Fireball flame before withdrawing oil support.	Yes No
4.	ESP fields are charged	Yes No
5.	APH Soot blowing stopped	Yes No
6.	SCAPH is isolated	Yes No
7.	Mill rejects cleaning is in progress	Yes No
8.	CBD silica / Drum Pressure Restrictions are monitored	Yes No
9.	Check all the level controllers like Drum , HOTWEL / Dearator , PW , CF , L.O , Gas temp are on auto	Yes No
10.	Both TDBFPs are in service and on auto.	Yes No
11.	All FCNRVs in extraction lines are open.	Yes No
12.	Oil support withdrawn.	Yes No
13.	Scanners show healthy flame.	Yes No

Remarks:

______________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

Energy Tab

Monday, January 29, 2024

Dadri stage-1 start up & shutdown Checklist

Unit Shutdown Checklist

1. Unit Just Tripped / Stopped

Activities after TG came on barring

Unit Start – Up Checklist

Date: ________

Just Before maintenance give clearance for boiler light up

Boiler lighted up and HP/LP bypass charged

2. Unit Synchronised

After crossing 60% load

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