| 摘要 |
<p>A plug valve, a check valve for a plug valve, a pressure regulator for a plug valve, and a check valve for a conduit. A plug valve having a plug closure member for sealing off the open end of a conduit and thereby preventing flow of a first fluid through the conduit, the plug closure member connected to a hollow stem, a channel for the flow of a second fluid extending through the hollow stem and plug closure member, the plug closure member and stem movable in a guide tube toward and away from the open end of the conduit, the plug closure member seatable in the open end of the conduit. In one embodiment the plug valve may have a pressure regulating member in the channel through which the second fluid flows. In another embodiment a check valve may be disposed within the channel to prevent flow of the first fluid down the hollow stem. The pressure regulating member and check valve may be combined in one embodiment. A conduit for use with a plug valve, the conduit having a check valve.</p> |
