Improvements in or relating to Valves

摘要

1,188,153. Valves. M. H. GROVE, and J. M. E. GROVE, [trading as M. & J. ENG. CO.]. 4 May, 1967 [9 May, 1966], No. 20705/67. Heading F2V. Leakage past the upstream seat of a gate valve 10 is detected by closing switch 47 at remote station 37 to vent the interior of the valve 10 through valve 38, and then closing the latter and closing switch 46 such that any rise in the internal pressure is sensed at 39 and indicated at 44. Valve 38 may be replaced by a three-way three-position valve (51) which can connect the interior of valve 10 to exhaust or to the inlet duct or to neither of these. The gate valve seats (Fig. 5) comprise a nylon ring 73 mounted in a groove in a spring- loaded carrier ring 74. Ring 73 carries a softer ring 76 and a seal ring 77.