Quick Closing Valves
A quick closing valve is an important part of the engine room fire fighting system. During emergencies, it cuts off one of the main sources of fire prominently present in the engine room - fuel oil.
The quick closing valves are installed in all fuel tanks in the engine room. They can be closed from a remote position outside the engine room, normally from fire control station. These valves are spring loaded and are normally operated by following methods:Wire-pulley system Pneumatic system Hydraulic system
Wire pulley system operation:Check for any slackness in the wire Ensure all the wires are seated on the pulley From the remote station, first release the required lever from its seat Pull the lever with a jerk to operate the required quick closing valve Once the quick closing valve is operated, the wire will be slackened
Pneumatic system operation:
A pneumatic cylinder with piston is fitted in the quick closing valve housing which operates the spring to close the valve. The normal working air pressure required is 7 kg/cm2 supplied from an air tank fitted in the fire station. This system covers all the oil tanks in the engine room.
A separate bank of quick closing valves, which includes main engine and generator engines fuel oil supply lines, is operated by a different local station fitted near the 2nd deck of the engine room or near the main starting air receiver. The air for operation of these valves is provided normally by the control air system.
Operating Procedure:Check the air tank in fire station is full Ensure the inlet valve of the tank is always open For operating the engine room fuel tank valve, go to the fire station To shut a group quick closing valve for tank system, operate/ push/ open the air valve for that quick closing valve This will supply the air to the piston instead of venting which closes the quick closing valve Emergency generator valve tanks are not included in the pneumatic system and a local wire pulley system is installed outside the emergency generator
The system is similar to pneumatic system with the operating media as oil.
Operating ProcedureCheck the hydraulic tank for oil level Ensure there is no leakages from any hydraulic piping For operating the engine room fuel tank valve, go to the fire station To shut a quick closing valve for tank system, operate/ push/ open the hydraulic valve for that quick closing valve This will supply the oil to the piston which closes the quick closing valve Emergency generator valve tanks are not covered and a local wire pulley system is installed outside the emergency generator
A Pocket Guide To Fixed Fire Fighting Systems and Emergency Procedures For Ship’s Engine Room (Author: Marine Insight)