| 摘要 |
<p>A pilot operated safety relief valve (14) having a main piston valve member (26). A dome chamber (42) is provided in the valve body (18) over piston valve member (26) and a cap (44) forms a closure for dome chamber (42). A pilot valve (46) is mounted on the cap (44) and has a diaphragm actuated fluid inlet sensing tube (60) received within a bore (30) of the piston valve member (26). Inlet fluid pressure is communicated through bore (61) of sensing tube (60) to the inlet fluid sensing chamber (84) on the outer side of diaphragm (65). Exhaust chamber (56) is positioned between dome chamber (42) and inlet sensing chamber (84). Adjustment spring (67) continuously urges O-ring (72) in dome chamber (42) to a seated position on seat (70). An annular clearance (78) is provided between sensing tube (60) and piston (26) for providing a restricted fluid flow between dome chamber (42) and the inlet (20).</p> |
