What is the working principle of the check valve?

Check valve is an automatic opening and closing valve, it does not require manpower or other operations. It relies on the flow of the pipeline medium to open or close the valve. It is mainly used to prevent the reverse flow control of the medium. The check valve has only one flow direction, that is, it can only flow along the water inlet and cannot be reversed. When the medium flows back, the valve disc is closed. 

The check valve is generally installed to prevent the medium from flowing back. A check valve is always installed at the outlet of water pump, it can prevent high-pressure water from flowing backward into the water pump, and the impeller of the water pump or other parts are loosened or damaged due to hydraulic impact, which may lead to accidents. In short, check valves are used in pipelines that prevent the backflow of the medium.

The principle of the check valve is very simple. As shown in the figure, the medium flows in the specified direction. When the flow pressure exceeds the opening pressure of the check valve, the disc is pushed open under the action of the fluid pressure, and the medium flows into the pipeline. Conversely, when the pipeline medium flows backwards, the disc is pressed against the body under the pressure of the fluid, and the valve is closed at this time, thereby cutting off the flow of the pipeline medium. Moreover, the greater the pressure of the backflow medium, the tighter the valve flap is closed, and the better the sealing effect, which completely eliminates the possibility of medium backflow.

More details of check valves, please go to https://www.mingpinmetals.com/Check-Valve-pl3017724.html