What are a start-up and shut down procedures for turbine-driven Cargo Oil Pump on board tanker vessel?
Before COP can be started it must be primed through from the tank. Separator and pump itself must be full of liquid and discharge valve closed. Important to fill the separator and pump slowly.
Start up
1) Lubricating oil sump to be checked for water contamination and drained as needed. Check LO and governor oil levels and top up to maintain normal working level.
2) Open the vacuum condenser inlet and outlet cooling water valves, cooling pump suction and discharge valves. Start the pump. Vent any air from the condenser.
3) Open ejector inlet and outlet valves.
4) Open lubricating oil cooler inlet and outlet cooling water valves. Start the pre-lubricating oil pump.
5) Recheck the oil level in the lubricating oil sump. The priming pressure should be around 0.3kg/cm2. Put the priming pump on auto.
6) Check trip cylinders for free movement out and that the trip latch is in a position to engage.
7) Open the turbine exhaust valves.
8) Open the vacuum condenser condensate pump inlet and outlet valves, balance line valves, condenser recirculation and level control valves.
9) Start condensate pump. Check hot well level is maintained.
10) Warm through the air ejector steam lines.
11) Open ejector drain to the vacuum condenser valve.
12) Note that working vacuum will t be achieved after gland steam is supplied.
13) Open the turbine drain valves, steam chest drain valves, steam line drain valves, steam trap valves and drain separator steam trap drain valves. This required to avoid excessive hammering and vibration while starting.
14) Gradually open warming-through valve. Warm and drain the steam lines and turbine.
15) Warm through and supply gland steam to the turbine gland. Adjust pressure to around 0.15 Kg/cm2.
16) Check whether the condensate vacuum, gland steam pressure, steam inlet pressure, and lube oil pressure are normal.
17) After one hour of warming up open master steam v/v slowly and shut the warming v/v.
18) Set the governor lever to start position the turbine should start rotating slowly.
19) Run COP in warm up mode and it will rotate at minimum speed for 3-5 minutes.
20) Change over the control cargo oil pump to Cargo Control Room.
Shut down
1) Close turbine main steam valve and gland steam valves.
2) Open turbine, steam line and steam chest drains.
3) Keep lubricating oil priming pump running.
4) Close turbine exhaust valves.
5) Shut down the ejector.
6) Stop the condensate pump.
7) Keep the water-cooling running for some time.
8) After the system has cooled down, close the LO cooler water inlet and outlet valves.
9) Keep lubricating pump running to reduce corrosion.
10) Stop cooling to the ejector condenser and seawater cooling to the vacuum condenser.
