Check Valve

摘要

1,193,359. Valves. GRAY TOOL CO. 22 Aug., 1968 [29 Nov., 1967], No. 40262/68. Heading F2V. A valve includes a housing 14, Fig. 2, having a through passageway 36 with a chamber 22 delimited at one end by a radially directed annular seat, a valve disc 58 having two aligned trunnions 60 laterally offset from a diameter of the disc and received in slots 32, 34 axially longer than the diameter of the trunnion, sockets 28, 30 communicating with the slots and containing compression springs 92 resiliently pressing the trunnions upstream against the housing, and further spring means 78 resiliently pressing the disc against the seat, whereby upstream fluid flowing against the disc moves the disc downstream by compressing the springs 92 and rotates the disc against the restoring force of the further spring means 78. The latter may be made from Inconel (Registered Trade Mark) and has a tip 88 connected by lateral coils to horizontal legs received in parallel grooves in the upper face of the disc 58. The seat is provided with an annular groove containing an O-ring 54 for engagement with the lower face of the disc. The body may consist of two parts in threaded engagement with each other and have a corrosion resistant cladding of stainless steel in a carbon steel jacket. Each part has an external flange for engagement by a clamp connector and an internal conical face to receive a sealing ring inserted between the valve and adjoining pipe section. Fig. 11 shows a further modification, for low pressure applications in which the springs engaging the trunnions 260 are omitted and a spring 278 anchored on a retainer ring 279 resists both longitudinal and pivotal movement of the disc 258. Guide ears 272 having surfaces 273 curved about the trunnion axis and a point below the trunnion axis bear against a shoulder 246 during displacement of the disc to ensure smooth operation. The Specification includes examples of dimensions for some of the valve parts.