Precautions when operating the boiler and exhaust gas economizer water circulating pump

1) During main engine running, always pay attention to the running condition of the boiler water circulating pump, and keep a sufficient quantity of water in circulation for the exhaust gas economizer. Never stop the boiler water circulating pump during main engine running.

2) After stopping the main engine, the boiler water circulating pump must be run continuously for at least 24 hours. (There have been cases of soot fires occurring after the main engine had been stopped for 12 hours.) It is actually desirable to keep the circulating pump operating constantly, even when the main engine has been stopped for an extended period of time. However, when water washing of the exhaust gas economizer is to be carried out, the boiler water circulating pump can be stopped within this 24 hour period.

3) Before starting the main engine, to avoid dry out of the inside of the heating tube confirm the operational condition of the boiler water circulating pump and confirm the water flow of the exhaust gas economizer. It is important to carry out adequate air purging in the piping when the boiler water circulating pump is re-started after water washing of the exhaust gas economizer.

4) Because the revolutions and discharge pressure and temperature of the boiler water circulating pump are high, the ball bearings and oil seals are usually used under severe conditions. Therefore, careful attention needs to be paid to the running condition of the pump, such as sound and temperature.

5) The following preventive measures against the incorrect operation and circulating pump sudden stopping should be carried out:

• When changing over the running pump, crewmembers should be arranged at the pump side and the engine control room. In the engine control room, all operations should be confirmed using monitoring devices etc. and reporting of the pump condition should be done by the crewmembers who are assigned pump side.

• Should the pump be accidentally stopped due to incorrect use of the stop/start button of a pump, very serious damage can be caused to the economizer. The close proximity of the stop/start button to other buttons may result in the accidental stopping of a pump. It is therefore very important that a protective cover is permanently placed over the button to prevent accidental usage.