Swing check valve is also called one-way valve or check valve, its function is to prevent the medium in the pipeline from flowing back. The valve whose opening and closing parts are opened or closed by the flow and force of the medium to prevent the medium from flowing back is called a check valve. Check valves belong to the category of automatic valves, which are mainly used in pipelines where the medium flows in one direction, and only allow the medium to flow in one direction to prevent accidents. This type of valve should generally be installed horizontally in the pipeline.