BigPatents India

A pressure relief apparatus (20) includes a valve (22) having a body (23). A shaft (56) is rotatably disposed in the body and has an exterior end (58) extending through the body. A plug (65), which may contain an internal passageway (72), is mounted on the shaft and is disposed in the fluid flow path (50). The body is engage able with the system to expose the plug to the pressurized fluid so that the pressurized fluid acts on the plug to exert a torque on the shaft which is offset from the center line of the plug. The apparatus further includes a linkage assembly (26) configured to translate the torque exerted on the shaft into an output force. A release device (181), such as a buckling pin (182), a magnet, an electromagnet or a fusible plug (258), is connected to the linkage assembly and is configured to release the shaft when the output force exceeds a predetermined limit. Preferably, the linkage assembly is adjustable to vary the magnitude of the output force corresponding to a given torque. A low torque seal (84) secured in place by a retaining ring (64) is disposed in the body to prevent fluid from leaking through the body past the plug. (FIG.1)