The working principle of the swing check valve is somewhat similar to the shut-off valve. The passage of the fluid through the lift check valve is also narrow, so the pressure through the lift check valve is larger than that of the swing check valve, and the swing is started. The flow rate of the check valve is limited.

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.

The check valve is an automatic valve whose main function is to prevent back flow of the medium, prevent the pump and drive motor from reversing, and discharge the container medium.

The ball of the floating ball valve is floating without a mounted shaft. Under the action of the medium pressure, the ball can generate a certain displacement and press on the sealing ring at the outlet end to ensure the sealing of the outlet end, which is a single-sided forced seal.