The sealing principle of lift check valve

The structure of the lift check valve is generally similar to that of the globe valve, and its disc is raised and lowered along the centerline of the channel. The sealing principle is: for the vertical lift check valve, it is closed by its own weight. Once the valve disc is closed, the pressure during the reverse flow of the medium acts on the valve disc to form a sealing pressure. The higher the pressure, the valve disc and the valve seat are sealed. The higher the specific pressure of the seal on the face, the easier it is to seal. On the contrary, the lower the medium pressure, the lower the sealing specific pressure on the sealing surface of the valve disc and the valve seat, and the more difficult the sealing is.

In order to ensure the sealing, it is necessary to ensure that the actual specific pressure of the sealing surface is greater than the necessary specific pressure to ensure the sealing, but also less than the allowable specific pressure allowed by the material. In this way, for the vertical lift check valve with higher working pressure, the sealing surface can be designed to be wider according to the allowable specific pressure of the material; on the contrary, for the vertical lift check valve with lower working pressure In other words, due to the low working pressure, the sealing force must be small. To ensure sufficient sealing specific pressure, the sealing surface needs to be designed to be narrower.

The fluid resistance of the lift check valve is relatively large. This is because during the flow of the medium, it is necessary to turn an S-shaped detour, but the action is reliable. Due to the structural relationship, it is only suitable for occasions with small diameters.

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