The butterfly check valve is a clip-on valve that consists of a valve body, a disc, a valve shaft and a spring. The butterfly check valve flap opens under the action of flowing medium from bottom to top, ie the medium flows in from the inlet and the outlet flows out. When the inlet pressure is lower than the outlet pressure, the valve flap is automatically closed under the action of the differential pressure of the flow, the spring force and the weight of the valve disc to prevent the medium from flowing backward.
