Classification of check valves
Lift check valve (Lift Check Valve):
Lift Check Valve (Lift Check Valve): The valve is opened by the medium pressure, when the medium flows in the opposite direction, closed by self-weight (sometimes closed with the help of a spring), so the lift check valve can only be installed in the horizontal pipeline, subject to the limitations of the installation requirements, commonly used in small-diameter occasions (DN ≤ 40mm).
swing check valve (Swing Check Valve, Flap Check Valve):
Is to rely on media pressure to open the valve, rely on media pressure and gravity to close the valve, so it can be used in the horizontal pipeline, but also can be used in the vertical pipeline (at this time the medium must be from the bottom up), commonly used in DN ≥ 50mm occasions.
Clamp check valve (Wafer Type Check Valve):
Structural size is small, low manufacturing cost, commonly used instead of lift and rotary check valve.
Shuttle Check Valve (Shuttle Check Valve) is also called axial flow check valve:
Used to solve the lift check valve can not be used in the vertical pipe.
Foot Valve:
The valve is used at the suction inlet of the suction pipe of the pump. It is equipped with a strainer to prevent foreign matter in the water from being sucked into the pump. The purpose of using the foot valve is: to fill the pump and the inlet pipe with water before starting the pump; to keep the inlet pipe and the pump body full of water after stopping the pump in case it is started again, otherwise the pump will not be able to start.
