Fuel Oil Tank Valves

Marine fuel tank valves are used on discharge, drain, and emergency isolation lines serving fuel oil tanks, where controlled shut-off and limitation of fuel leakage are required during maintenance, equipment failure, or machinery-space incidents. Valve selection should be based on the vessel piping standard, flange pressure class, fuel type, tank connection location, and whether local or remote operation is required.

This category includes brass flanged valves to JIS 10K, straight-through pattern, for fuel tank service. Type F7398 is a self-closing drain valve intended for fuel discharge or draining duty. Type F7399 is an emergency shut-off valve intended for rapid isolation of the fuel line. Both types are specified to JIS dimensions, with flanged ends, brass body construction, and nominal pressure rating 10K.

The self-closing function on drain valves reduces the risk of a line being unintentionally left open after sampling, draining, or maintenance work. The emergency shut-off function is evaluated as part of the vessel’s fuel isolation philosophy, particularly on tanks supplying main engines, auxiliary engines, burners, or fuel transfer systems.

During installation, attention should be given to operator access, flow direction, seat tightness, gasket compatibility with fuel oil, galvanic compatibility with adjoining pipework, and protection against vibration. Maintenance should include periodic verification of return action, stem condition, packing integrity, flange tightness, and the presence of deposits or sludge that may affect shut-off integrity and response time.