| 摘要 |
<p>A dual isolation valve (10) comprises: a valve body (12) with opposed inlet (14) and outlet ports (40) that defines an inner cavity; a first valve member (22); and a second valve member (34). The valve members (22, 34) (preferably plugs) have narrower first ends (22a, 34a) and wider second ends (22b, 34b) and are rotatably mounted within the valve body cavity for rotation about a first and second axis of rotation substantially perpendicular to the flow axis F defined by the inlet and outlet ports (40). The valve members include substantially rectangular flow passages (24, 36). The first ends of the valve members exte nd away from the second ends along the first and second axis of rotation in opposed directions, and the valve members are rotatable between an open position, in which the flow passages (24, 36) are oriented to be generally aligned with and located on the flow axis F to enable fluid entering the inlet port to pass through the flow passage, and a closed position, in which the flow passages (24, 36) are oriented to be generally perpendicular to the flow axis F to enable fluid entering the inlet port to pass through the flow passage, and a closed position, in which the flow passages are oriented to be generally perpendicular to the flow axis F to prevent fluid entering the inlet port fr ompassing through the flow passage. In this configuration, the flow of fluid through valve can be disturbed less than with prior art dual isolation valves while permitting extensive flow through the valve.</p> |
