Installation method of check valve

Swing check valve: The disc of the swing check valve is in a circular shape and rotates around the axis of the valve seat channel. Due to the streamlined channel inside the valve, the flow resistance is smaller than that of the lift check valve. It is suitable for large diameter applications with low flow rates and infrequent flow changes, but not suitable for pulsating flow. Its sealing performance is not as good as that of the lift check valve. Swivel check valves are divided into three types: single disc, double disc, and multi disc. These three forms are mainly classified according to the valve diameter, in order to prevent hydraulic shock when the medium stops flowing or flows back.

Lift check valve: a check valve with a disc sliding along the vertical centerline of the valve body. Lift check valves can only be installed on horizontal pipelines, and on high-pressure small diameter check valves, the disc can be spherical. The shape of the valve body of a lift check valve is the same as that of a globe valve (which can be used interchangeably with globe valves), so its fluid resistance coefficient is relatively large. Its structure is similar to that of a globe valve, with the same valve body and disc as the globe valve. The upper part of the valve disc and the lower part of the valve cover are processed with guide sleeves. The guide sleeve of the valve disc can freely rise and fall within the guide sleeve of the valve disc. When the medium flows downstream, the valve disc opens by the thrust of the medium. When the medium stops flowing, the valve disc falls vertically on the valve seat, playing a role in preventing the reverse flow of the medium. The direction of the medium inlet and outlet channels of the through type lifting check valve is perpendicular to the direction of the valve seat channel; The vertical lifting check valve has a medium inlet and outlet channel direction that is the same as the valve seat channel direction, and its flow resistance is smaller than that of the straight through type.