| 摘要 |
<p>The seal assembly is disclosed for use with a valve having a trim cage (24) with an inner surface extending along in axis and a plug (25) sized to fit inside the trim cage (24) inner surface, wherein the plug is adapted to move along the axis thereof. A seal ring (29) is attached to an upstream portion of the cage (24) to effectuate a seal with the plug (25). The plug is equipped with a wiper seal (35) that cleans or otherwise removes debris from the seating surface (32) of the seal ring (29), an interior surface of the seal ring (29) and an interior surface of the cage (24) during both the opening and the closing of the valve. Thus, the valve is self-cleaning. Further, the wiper seal (35) delays throttling action through the valve until the plug has moved a substantial distance away from the seating surface (32) of the seal ring (29) which reduces high pressure abrasive flow against the seating surface of the seal ring (29) to reduce wear on the trim set.</p> |
