Application of automatic recirculation valve in pump system protection

Automatic recirculation valve, a kind of pump system protection valve, has a simple integrated structure, which can improve the value of NPSH of centrifugal pump to avoid the cavitation erosion in pump. Even if the outlet valve is closed by misoperation, the minimum flow in pump with automatic recirculation valve can recycle in bypass pipe and the outlet pressure of pump can be reduced by integrated multistage pressure release valve in bypass pipe. Some negative influences like vibration and valve surge can be reduced. And centrifugal pump and valve damage can be avoided. As a result, the centrifugal pump is protected and the safety of system is guaranteed. Automatic recirculation valves have been successfully applied in process pump system in the engineering design of refined oil tankfarm in Beira, Mozambique. Facts have proved that all the design guarantee figures have been reached since the valve has been put into production. And it has also obtained the approval of the owner.