Precautions for Starting and StoppingPosted by: MarinerGalaxy
The engine should be tried out from the engine control room and bridge before departure from a port.
On starting the engine, the following should be checked:
- Direction of propeller rotation corresponds to the telegraph order.
- Turbochargers for proper lubrication and running.
- Lubricating oil pressures.
- External temperature of air starting pipe.
- Whether all the cylinders are firing.
- All the units exhaust valves are operating correctly and their temperatures.
- Any abnormal noise.
- Temperatures of lubricating oil, camshaft lubricating oil, fuel oil, cooling water, scavenge air, thrust and intermediate bearing.
- Working of cylinder lubricators and oil mist detector.
The engine speed should be increased gradually as recommended by the manufacturer. Most of the engine automatic control systems of main engine
have a loading program which loads the engine gradually once the required speed is set. Monitor and maintain the parameters within the limit.
The units in which maintenance were carried out should be inspected thoroughly. The running in procedure should be followed if cylinder liners, piston rings or any main bearings were renewed.
Procedures to follow with the main propulsion plant, once Full Ahead is given (including, changing over to heavy fuel oil for the main engine, putting the Exhaust Gas Economizer and Fresh Water Generator, on load).
For the propulsion plant to operate efficiently it is essential that, once, the manoeuvring is over, correct parameters are steadily maintained as per the engine maker’s specifications. Hence at this stage a proper Engine room round needs to be taken to ensure that all parameters have steadied down and are maintained so, and that there is no abnormality. The following actions need to be taken:-
- Close the main air starting valve.
- Check the jacket cooling water temperature and if preheating steam / auxiliary engine outlet was used, ensure same is shut off so that no further external preheating is being done.
- Once the additional fluctuating power requirements for winches, windlass, cranes etc. are over, stop the second generator.
- If high sea suction was in use, change-over to low sea suction (depending on the draft).
- Change over to HFO if Diesel/Gas oils/LS fuel oil was being used during manoeuvring.
This change over of fuel should only be done if the vessel is out of Sulphur Emission Control Area (SECA) and that should be done as per the shipboard procedures along with relevant record keeping.
- Start the fresh water generator.
- Load the shaft generator, if fitted.
Putting the exhaust gas economizer on load: Following procedure to be carried out before starting
- Ensure the boiler-circulating pump valves are free.
- Slowly open the inlet/outlet valve.
- Check valves, flanges etc. for leakage.
- Allow economizer unit to warm through, with the temperature and flow of the exhaust gases from the main engine having steadied (once fullaway is given, with no immediate need of manoeuvring). Unless the economizer unit is hot enough (too much heating may lead to lifting of the safety valves), the circulating pump must not be started for preventing acid-condensation due to the sulphur content in the exhaust gases.
- Start the circulating pump (with the water temperature hot enough for preventing any thermal shock to boiler) and ensure that the stand-by unit is on auto mode.
- Check pump pressures, motor load etc.
- Check that the gas side differential pressure manometer is operational.
Taking the economizer off load
- Soot blow prior to the end of sea passage
- Ensure steam dump-valve settings are adjusted once the manoeuvring is set to start
- Ensure that the main boiler is in auto mode and cuts in when the steam pressure drops
After main engine stops and circulation of the water to/from the economizer is required to be interrupted.
- Stop the circulating pumps, before the boiler gets substantially cooled, for reasons explained in the 4th bullet under “Putting the exhaust gas economizer on load”, above.
- Shut the boiler circulating pump valves.
- Procedures to follow with the main propulsion plant, once the ship gets near a destination port, i.e., into maneuvering mode (including, changing back to diesel oil for the main engine, taking the Exhaust Gas Economizer and Fresh Water Generator off –load, keeping air bottles pressed-up, starting the second generator etc.).
- Take standby generator on load and offload shaft generator.
- Ensure Main Engine Auxiliary blowers and Boiler is in auto mode
- Stop the Fresh Water Generator while monitoring jacket cooling water temperature.
- The Diesel oil (assuming this would be used for manoeuvring) settling and service tanks are pressed up,
- Check and comply with the standing instructions for fuel change over
- Change over the sea chest if required.
- Drain the air bottles, check that both the bottles are pressed up and open main starting air valve.
- Take rounds of steering gear room to check parameters /oil levels
- Carry out steering gear tests in consultation with wheel house.
- Once the manoeuvring rpm is reached, proceed with engine test in ahead and astern direction in consultation with the navigation bridge.
Procedures to follow with the main propulsion plant, once Finished with Engines, is given
- If manoeuvring was on diesel oil, stop the fuel oil pumps. Fuel oil pumps to run and temperatures to be maintained as per shipboard operating procedures, if M.E. manoeuvring is done on heavy oil
- Close main air starting valve.
- Stop ME Auxiliary blowers.
- Open indicator cocks of all the units.
- Lub oil pumps should run at least 30 minutes after stopping Main Engine.
- Main engine jacket cooling water to be kept on preheat, unless the next sailing particulars are unknown.
- Stop the boiler water circulating pump, once the economizer has moderately cooled down.
- Depending on power requirements at port, check and offload the additional running generator.
- Take rounds of the engine room.
Prior to port arrival
In engines where manoeuvring is carried out on diesel oil, the change over should be carried out one hour before manoeuvring. Start an additional generator and take on load before manoeuvring. Try out the engine in astern direction and ensure that reversing mechanism is working properly.
After arrival in port
When the finished with engine order is given, switch over to engine control room control.
Open the indicator cocks. Take permission from bridge and blow through the engine to expel the residual exhaust gases. Engage the Turning Gear. Turn the engine with turning gear.
Stop the lubricating pump after two hours. In engines where manoeuvring is done on heavy oil do not stop the fuel oil circulating pump. Maintain the temperature of the fuel oil. Keep the jacket cooling water circulating pump on maintain the prescribed temperature by preheater .