| 摘要 |
<p>The valve includes a closure disc (34) sealable at its rim to a valve seat (18) so that in this position the seat (18) and rim define between them an annular space (54) which is connected to a port (60) by passages (54, 56, 58) extending through a mating face (e.g. carbon fibre gasket (22)) of the valve seat (18). As shown the space (54) is a recess in the disc rim defined between fibre seal rings (46, 48) but other arrangements are disclosed in which the seal rings and/or recess may be accommodated in the valve seat. The port (60) may be used for leakage detection, pressure monitoring or bleeding, or fluid injection.</p> |
