Check valve is to rely on the media itself flow and automatically open, closed disc, used to prevent the backflow of the valve, also known as the non-return valve, one-way valve, countercurrent valves, and back pressure valve. Check valve is an automatic valve, its main role is to prevent the flow of the media, prevent the pump and drive motor reversal, as well as the release of the container medium.

Check valve, the function of this type of valve is to allow only the media to flow in one direction and to prevent the flow in reverse direction. Usually this valve is automatically working, in a direction of flow of fluid pressure, the disc opened, fluid in the opposite direction, by the fluid pressure and the weight of the disc valve flap acting on the seat, thus cutting off the flow.