摘要 |
A pressure rise rate limiter valve (10) is designed to limit a pressure surge of a gas or fluid through a rapidly opening valve, thus avoiding hazardous heat buildup in the system. The valve has an inlet port (14) and an outlet port (16) with a spool (24) having a passageway (32) communicating between the two ports. Said passageway (32) also communicates with a cavity (123) in the valve housing (12) through a restricted orifice (36) located at the end opposite the outlet port (16). The gas introduced at the inlet (14) is directed through a series of feeder ports (38) in the spool (24) into the passageway (32) wherein the gas is dispersed both toward the outlet port (16) and toward the cavity (123) in the housing (12). The flow directed towards the cavity (123) causes a pressure rise at the wall surrounding the restricted orifice (36), which urges the spool (24) axially towards the cavity ( 123), compressing a retaining spring and moving the feeder ports (38) out of alignment with the inlet port (14), thereby cutting off the gas flow. Once the gas bleeds through the restricted orifice (36) into the cavity (123), the downstream pressure and the cavity pressure will begin to equalize, whereupon the compressed spring (46) gradually urges the spool (24) back towards the full flow position.
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