Shut-Down Procedure: 500 MW
- Reduce load from 500 MW to 400 MW
- Gradualy Reduce Pr SP from 170 ksc to 130 ksc, Load is still 400 MW
- Take unit of TFM
- Stop Topmost Mill to reduce firing, Reduce o/p of fuel maser manually
- Close HP Heaters 5B & 6B Extraction block valves, Drip also closes slowly
- Boiler Pr increases momentarily then drops as FW Temp has reduced
- Further Reduce o/p of fuel master, steam temperatures.(Ensure TFM & IP mode)
- The load will drop automatically in TFM to maintain Pressure SP
- Stop one more mill, reduce o/p of fuel master manually
- Maintain Drum, Furnace Pressure, PA Header Pressure during transient
- Now Load is around 350 MW with 4-5 mills
- Reduce Pr SP to 100 ksc and reduce fuel master and
- 3 Feeders with Loading mill((>75%, 45 Tons) may not need oil support
- Adjust HPBP to match existing Throttle Pressure, LPBP in auto
- Transfer IP mode to LP mode, Reduce Load Ref further
- Change-over UT to ST at 200 MW
- Reduce firing in one of the three mills, take out that pulverizer before that take gun support for the Running mill (AB Elevation)
- Close Extraction of LPH 2. 3 once load <100 MW
- Transfer FRS 100% to FRS 30 %
- Stop one CEP, Close PRDS supply from Unit
- Maintain Hotwell, Deaerator level
- Take HPBP and LPBP in manual and reduce Opening of HP/LP bypass
- Stop bottom Pulveriser after cutting it to minimum
- Bring BT to the horizontal position
- Remove the oil guns, moment 4th corner gun stopped, Boiler will trip and Loss of all fuel flow alarm comes
- MFT Tripped alarm comes, Both MFR relays REd lamp glows
- Bring air flow to less than 40% by FD Fan blade pitch
- Close HPBP, LPBP manually and Increase SP Higher than Existing Pressure
- Purge the boiler, MFR got reset
- Maintain air flow between 30% to 40%
- After maintaining drum level, close FRS line, close MDBFP discharge valve
- Wait till BCW suction temp comes 93 then Stop BCW and then MDBFP
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