摘要 |
<p>A recirculation valve for cooling a centrifugal pump. The invention comprises a valve casing having a first chamber for connection to a centrifugal pump and a second chamber for connection to a fluid outlet, a recirculation port for redirecting fluid from the first chamber to the centrifugal pump. Between the first and second chambers is a check valve means for permitting fluid flow from the first to the second chamber. Connected to the check valve means is a hollow cylindrical valve stem permitting flow from the first chamber to the second chamber. The check valve means is comprised of a circular disc which opens when the fluid pressure in the first chamber exceeds the fluid pressure in the second chamber and closes when the fluid pressure in the second chamber approaches that in the first and intermediate chambers. A two angle control surface between the check valve disc and the valve casing controls the position of the check valve relative to the flow of fluid past the valve. A recirculation valve means caused by the hollow cylindrical tube controls the amount of fluid flowing from the first chamber to the recirculation port. When the recirculation valve means is open, flow through the recirculation port is impeded. When the valve means is closed, recirculation flow is permitted.</p> |