Muffler valve is the rely on the media itself, the flow of automatic opening and closing the valve, backflow valve to prevent the media, also known as check valve, check valve, check valve upstream valve silencer, and back pressure valve . Check Valve is an automatic valve, and its main role is to prevent the media back to prevent the pump and drive motor reverses, and the container medium discharge. Check valve can also be used to the pressure may rise to more than one system, the auxiliary pressure supply system pipeline. Check valve can be divided into Swing Check and Lift Check Valve.