The wafer check valve is applied to various lines of Class150~Class2500 and PN20～PN420 to prevent the medium in the pipeline from flowing back. Different materials are used, and the check valve can be applied to water, steam, oil, nitric acid, acetic acid, oxidizing medium, urea and other media.

A ball check valve is a check valve in which the closing member, the movable part to block the flow, is a ball. In some ball check valves, the ball is spring-loaded to help keep it shut. For those designs without a spring, reverse flow is required to move the ball toward the seat and create a seal.

The swing check valve is also called a check valve or a check valve, and its function is to prevent the medium in the pipeline from flowing backward. The valve of the opening and closing member is opened or closed by the medium activity and force to prevent the back flow of the medium.

A swing check valve or tilting disc check valve is a check valve in which the disc, the movable part to block the flow, swings on a hinge or trunnion, either onto the seat to block reverse flow or off the seat to allow forward flow.