CLA-VAL 50-48 : Pressure Relief & Back Pressure Control Valve
The Cla-Val Model 50-48 Pressure Relief & Back Pressure Control Valve is a hydraulically operated, pilot-controlled, modulating valve designed to maintain constant upstream pressure within close limits. This valve can be used for pressure relief, pressure sustaining, back pressure, or unloading functions in a by-pass system. In relief applications, the valve opens fast to prevent upstream pressure from exceeding the maximum pressure setting while closing gradually to prevent a surge in the system. In the back pressure control applications, the valve modulates to maintain constant upstream pressure, regardless of changes in demand, preventing the upstream pressure from falling below the minimum pressure setting. Operation is completely automatic and pressure setting is easily adjusted. If a check feature is added and a pressure reversal occurs, the downstream pressure is admitted into the main valve cover chamber, closing the valve to prevent return flow.