| 摘要 |
<p>1529532 Valves FMC CORP 19 Jan 1977 [23 Feb 1976] 02046/77 Heading F2V Lugs 70, 72 on the downstream side of check valve closure flaps 16, 18 are wedged against a stop shaft 26 so that the flaps remain in a stable open condition during high flow. The shaft 26 and the shaft 20 which supports the flaps are loosely mounted in the valve housing so that they may be forced together when the lugs 70, 72 engage the shaft 26. A resilient sealing ring 52, 54 for each flap 16, 18 comprises a main body portion which provides a seal against high back pressure and a bead 80, 82 which seals the valve against low back pressure. The sealing rings 52, 54 form the invention of Specification 1,529,533.</p> |
