Post on 12-Nov-2014
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Prepared By:Pranesh KumarPravin Gothwal
Vivek ShrivastavaRohtash Garg
POST TRIP ACTIVITIESCheck that all ESVs and IVs are closed and all
HPCVs & IPCVs are closed.Check that the swing check valves on cold reheat
line are closed and the extraction NRVs for Extractions 2,3,4,5,6 are closed from the indications available on turbine panel in UCB.
Open the drains before HPCV i.e MAL11, MAL 12, MAL - 13, MAL – 14 by operating its pushbutton on the turbine panel
At turbine speed of about 2850 rpm observe AOP-1 cut in on auto. In case if it fails to do so .,start the pump with manual command
At turbo-generator speed < 510 rpm observe the auto starting of JOP-1 .
Confirm the jacking oil pressure >125 Ksc. Start the JOP-1 in case of auto failure.
At Turbo-generator speed < 210 rpm observe that the barring gate valve starts opening. Note the time which will mark the end of coasting down period.
Confirm that the Turbine steadies at barring speed.
Check that the MAL drain valves are open through SLC drains as per requirement, if not open by manual command.
Condenser Vacuum may be killed at this stage if Bypass ( HP-LP) operation is not required and steam generator not in service.
ALCS to be retracted.Close manual valve for HPBP spray.Isolate SH ,RH spray system .
Important Pre-activitiesPTW should not be issued for bottom mills A
to D if any major breakdown is not reportedCST level adequate before boiler filling can
be ensuredOil gun cleaning doneHFO Day tank level adequate
BOILER SIDE ACTIVITIESBottom ash area – S/C, C/G can be taken i/s
after slag bath filling/trough seal chargingLow Point Drain Header related v/v should be
closed before boiler filling clearance receivedEBD manual isolating valve opening can be
ensuredFRS low and high range block valve and
control valve operation can be checked onceEco. R/C valve electrically normalized
At least two ESP pass I/O damper open (if permit not pending)
If any permit issued on any fan ID/FD/PA, its electrical and mechanical normalization (Suction/Discharge damper/IGV/Scoop/Blade pitch/EPB releas\ed etc.) should be ensured after permit cancellation.
Oil gun should be normalized (i.e. opening manual isolating valve of each gun can be ensured) from HFO/Atomising steam side.
HFO/Atomizing steam station should be normalized and can be charged after clearance from MM (in case of any permit issued)
Other unit HFO R/C v/v to be closedAll Coal mills should be normalized
electrically and mechanically(Air supply for HAD/CAD/HAG /CAG
operation checking done, LOP running and pressure healthy)
Phase failure of all Coal feeders can be re-setted
Purge permissive except Drum level normal and Air flow can be made ready
APH S/B lined up from AUX. PRDS SH/RH spray station normalization can be ensured
ESP field no communication failure can be ensured
S.H. air vents opening can be ensured
If boiler filling to be done by boiler fill p/p, fill p/p to be normalized & lined up. Trial to be taken
TURBINE SIDE ACTIVITYAll MAL drains & FT-5/6 drains manual isolating
valve opening can be ensured/no fault on any MAL valve
Normalize EHC, Stop valve gagging can must be removed
TDBFP seal water pressure to be normalized (if throttled) and main pump engaged/Gland steam pressure adequate
ATRS panel key availability can be ensured All SGC (oil /Evacuation/drain) faults not
persisting
Vacuum pulling Both CW pass charging ensured before one hour of light up Aux. PRDS HT/LT drains manual valve open, Drains can be open 30 min.
prior to vacuum pulling. Main turbine gland sealing steam temperature can be ensured before
vacuum pulling. (Aux. PRDS level HT header gland seal steam motorized v/v and 8.5m
Manual isolating v/v of seal steam and manual/motorized drains open Second ECW p/p can be TIS PW/Hydrogen/Exciter cooler normalization can be checked Hydrogen pressure as per normal working range can be ensured Generator side line and bus isolation closing from S/Y can be
communicated
AFTER SYNCHRONIZATION
ALCS to be advanceBall cleaning system to be taken in serviceAll energy drains to be checkedCBD to tightenAPH S/B C/O to be doneESP field to be charged after oil gun withdrawalAfter synchronization HP evacuation line closing can be ensured
•M/C on Load . •SH/RH spray control on auto. •Drum level control on auto. • Furnace pressure control on auto. •Aux. Steam pressure/temp. Control on auto. •Mill temp. on auto. •PA control on auto.
• SADC on auto. • HFO temp is adequate . • Four mills are in service(for Stage I)/ Six mills a• AB, CD, EF elevation oil guns are available. • Burner Tilt operation OK. • HP /LP bypass on auto. • EBD is available for operation. • FRS high range in service and low range is avai• Fire fighting equipments are available. • WW & APH Soot blowing system is available.