Swing-up check valve is one of the most widely used check valve series. The disc of swing-up check valve is disc-shaped and rotates around the rotating axis, making the inner passage of the valve streamlined, with small flow resistance. It is suitable for large caliber occasions with low flow rate and unstable flow. Swing-up check valve has three types: single-disc, double-disc and multi-half. These three types mainly depend on the caliber of the valve. It can effectively alleviate the washout of the disc and body seals when the medium backflow, thus prolonging the service life of the valve.