| 摘要 |
<p>Improved burst disk-type pressure responsive valve assemblies (20, 184) of the pressure relief and shutdown variety are provided which utilize frangible burst disks (30, 204) which largely determine the set point pressures for the valves. The assemblies (20, 184) include a housing (22, 186) having an inlet (24, 188), an outlet (26, 190) with a valve seat (28, 192) therein. The housing (22, 186) also supports a frangible burst disk (30, 204). An actuating unit (32, 210) within the housing (22, 186) includes a shiftable, pressure responsive piston (78, 212) supporting a valve stem actuator rod (82, 214); the rod (82, 214) is operatively coupled with a disk actuating element (84, 216) located adjacent a face of the rupture disk (30, 204). When an overpressure is sensed at the inlet (24, 188), the actuating unit (32, 210) serves to burst the disk (30, 204), allowing the piston (78, 212) to move relative to the valve seat (28, 192) to establish or close communication between the inlet (24, 188) and outlet (26, 190). The valve assemblies (20, 184) can be easily repaired or retrofitted in the field, without the need for extensive dismantling of conduits or the like. Use of disks (30, 204) which rupture during valve operation affords a visual indication of valve operation and permits fabrication of high capacity, long stroke length valves.</p> |
