| 摘要 |
<p>A pressure relief valve 10 comprises a valve body having an inlet 34, a valve seat 36, a valve closure member 38 engageable with the valve seat, and a spring 40 for biasing the valve closure member 38 into engagement with the valve seat 36. The valve further comprises a valve closure abutment member 54 and second springs 56, 58 for biasing the valve closure abutment member 54 into engagement with the valve closure member 38, thereby further biasing the valve closure member 38 towards engagement with the valve seat 36. Retaining means 92 retains the valve closure abutment member 54 in position against the force of the second springs 56, 58 when the valve closure abutment member 54 has been displaced a predetermined distance from the valve seat 36.</p> |
