| 摘要 |
<p>A disc valve includes a seat ring having a butt portion anchored to the body of the valve and a seal portion which extends axially from the butt portion. The disc of the valve is axially aligned with the seal portion of the seat ring so that the valve is sealed via engagement of the seal portion with the periphery of the disc. An annular cavity is formed about the seal portion of the seat ring and opposite ends of the cavity are vented to the valve chamber on opposite sides of the disc. An elastomeric seal disposed in the cavity is responsive to pressures of opposite ends of the cavity to close the vent to the low pressure side of the disc such that the higher of the fluid pressures on opposite sides of the disc is exerted on the outer periphery of the seal portion of the seat ring to force the seal portion against the disc when the valve is closed.</p> |
