| 摘要 |
<p>A walled body, has apertures formed in front and rear walls thereof in which resilient seats are set. The latter sealingly engage a plate-type gate, centrally apertured for aligr.ment with the seats, to define a portway through which to convey pipeline media. The gate is movable through the body to open and close the portway, and the body has sealing at the top and bottom to define thereof a pressure-containing shell. Further, sides of the body have openings formed therein, sealed off by removable plates. Exposure of the side openings allow for the venting of any seat leakage to the atmosphere, and inhibit any chance of solids buildup around the seats. The body is boltable to an upstream pipe of a pipeline, or for interpositioning in a pipeline.</p> |
