DUAL PILOT MANIFOLD ASSEMBLY FOR A SAFETY RELIEF VALVE

摘要

A manifold assembly (10) for operating a safety relief valve (12) includes a manifold block (60) having a block inlet port (230), a block dome pressure port (232), and a pair of control cavities (220 and 222) each adapted for receiving a pilot valve (70) or auxiliary control member (80). Inlet control valves (74, 84) dome pressure control valves (76, 86) and test control valves (78, 88) are each mounted on the manifold block. One of the pilot valves may be maintained on-line for controlling operation of the safety relief valve, while the other pilot valve may be isolated for service. A cartridge pilot valve assembly (70) includes a bushing (126) for facilitating installation and removal of the cartridge valve assembly from the valve block. An improved metal washer (122) is provided having inner and outer knife edges (330, 334) for sealing engagement between the valve body (110) and the block (60).