Safety stop valve for gas pipe has spring-loaded flat plate which remains in open position with gas flow below threshold value and moves to closed position if flow exceeds threshold

摘要

The stop valve (1) has a flange (6) which fits in the gap between two sections of pipe (2,2'). It has a cylindrical outer surface (8) in contact with the inside of the upstream pipe, with a groove (10) accommodating a sealing ring (12). It has a conical valve seat (36) against which the valve disk (24) may be forced by the drag caused by the gas flow (32). The valve disk has a sealing ring (26) at its edge. A spider (33) supports a cylinder containing a spring surrounding a central rod (16) supporting the disk. The spring is compressed as the disk moves toward the valve seat.