Check valve is a kind of valve whose opening and closing parts depend on medium flow and force to move and prevent medium backflow.

The check valve is an automatic valve, which is mainly used for one-way flow of medium on the pipeline. Only one-way flow of medium is allowed. Fluid under pressure causes the disc to open and flow from the inlet side to the outlet side. When the pressure at the inlet side is lower than that at the outlet side, the valve disc will automatically close under the action of fluid pressure.

Check valve can be divided into Wafer Check Valve, Lifting Check Valve, Swing Check Valve and Counter Weight Check Valve according to its structural characteristics.

Wafer Check Valve

1. The flow resistance of wafer check valve is relatively large, it is not applicable to the outlet of high-pressure (Class 900 and above) pumps and compressors; Not suitable for pulsating medium conditions; Not suitable for oxygen conditions.

2. Due to the structure of the wafer check valve, it is not suitable for large diameter (DN600 or above) and high pressure (Class 900 or above) occasions.

3. Wafer check valve should be installed horizontally as far as possible. If it is a vertical pipe, make sure that the medium flows from top to bottom.

Lift Check Valve

1. According to the working principle, the lifting check valve can only be installed in the horizontal pipeline.

2. Compared with swing check valve, its flow resistance is larger. Lift check valve is not suitable for large diameter (DN50 and above) occasions, but generally suitable for DN40 and below.

Swing Check Valve

1. Swing check valve should be installed horizontally as far as possible. If it is a vertical pipe, make sure that the medium flows from top to bottom.

2. Due to structural limitations, swing check valves shall not be used for DN40 and below pipes.

3. For large diameter pipeline (such as DN400 and above), it is recommended to use inclined swing check valve.

Counter Weight Check Valve

1. Select as needed.

2. Counter weight check valve is used in places where severe water hammer may occur.