| 摘要 |
<p>A safety valve comprises a valve body (11) including an annular valve seat (5) which comprises a seating portion (6) surrounding an annular lip (4) upstanding from that seat, a slidable plunger (10), an elastomeric seal (13) carried in a recess (12) of the plunger, and means for biassing the plunger in a direction (A) towards the valve seat to force the seal into sealing contact with the lip (4) and the valve seat. In order to limit deformation of the seal during periods between actuation of the valve, the full depth of the seal (13) lies within the length of the plunger (10) so that, in the closed position of the valve an end face of the plunger rests in direct contact with the valve seat (5). <IMAGE></p> |
