Cleaning procedure for sea chest filters
Since there are two or more sea suctions, before opening a sea suction for maintenance, other sea chest must be put in use with proper isolation of valves. After change over, the sea water pressure has to be monitored for any abnormality. If everything normal, the sea chest can be opened up and filter element can be taken out and cleaned.
1. Put the unused sea chest in use by opening the valves in proper sequence.( purge the sea chest out of air by keeping the vent open)
2. When all the air is purged, after ensuring sea water coming out of the vent, then close the vent and open the other valve to put the sea chest in use.
3. Isolate the sea chest on which the maintenance is to be carried out.
4. Open the vent and drain valve on the sea chest.
5. Then with proper tools,equipments & lifting gears open the top cover of the sea chest and pull the filter element out. Take out all the debris like fish, shell, sea weeds, barnacles etc..
6. Put back the filter element and properly close the top cover. Tighten the cover by tightening the bolts of exactly opposite side.
7. After tightening, shut the drain and keep the vent open to purge all the air out of the sea chest by opening the sea chest valve.
8. After purging, shut the vent and keep the cleaned sea chest as stand-by.