PRESSURE-SENSITIVE TEMPERATURE-RESPONSIVE ROTARY VALVE FOR CRYOGENIC TEMPERATURES

摘要

Abstract of the DisclosureA rotary valve for providing control of fluid flowthroughout a wide range of pressures and temperatures. Thevalve includes a pressure-sensitive and temperature-responsiveflexible annular seat that cooperates with the valve's flowcontrol element to establish a fluid seal, and a temperature-responsive rigid energizer ring for maintaining both a radialand an axial load on the seat through a wide range of ambient:and low temperatures. The valve seat includes an annular,radially outward extending support leg that is held in positionagainst a radial surface of the valve's body by the energizerring, at least one outer annular sealing lip that extends is agenerally axial direction from the leg, and a central sealinglip that extends radially inwardly from the support leg towardthe flow control element. At ambient temperatures a portionof the outer sealing lip presses against the flow controlelement when the valve is closed, and when the temperatureis lowered toward the cryogenic range the central sealinglip moves into fluid-tight contact with the flow controlelement, thereby providing an additional seal at the lowertemperatures. The energizer ring has a generally wedge-shapedcross-sectional configuration, and is held in position in thevalve body by a retainer ring that is releasably secured, asby screws, to the valve body for quick and easy servicing ofthe seat. The energizer ring has a frusto-conical radialsurface that cooperates with the corresponding surface on theretainer ring to maintain the energizer ring constantlywedged tightly against the valve seat, thereby assuring thatthe seat is retained securely in the valve body and is con-tinually forced against the valve's flow control elementthroughout the entire range of operating temperatures andpressures.-1a-