setting mechanical pump driven by pressure, the correct way is to make the driving pressure higher than the back pressure 1-1.5kg/cm2 (15-20psig). This is in most cases is correct. But sometimes to meet the requirements of displacement pump needs to be the driving pressure was set slightly higher. Driving pressure is high, the downside is easy to wear and tear caused by the intake valve. If the driving pressure is higher than required value, would cause serious wear and tear of intake valve had to replace the intake valve in advance. 

      In this case, it is recommended the use of pressure reducing valve or pressure reducing valve stations. Valve can either allow the pressure to maintain the drive to meet the pump displacement of set pressure, but also can protect the intake valve from wear and tear. In addition, the use of space narrow, it is recommended to use with a set of steam pipe valve stop. Pump water in the pump process, the set of steam pipes to pump steam supply pump so as to provide a buffer. The buffer zone so that the whole devices, gentle movements to reduce wear and tear on the valve.