Butt valve

The utility model discloses a butterfly valve, which belongs to the technical field of valves and comprises a valve body, a driving mechanism, a valve rod, a valve seat and a valve plate. The valve plate comprises a shaft sleeve and semicircular plate hinges arranged on the two sides of the shaft sleeve and arranged on the same plane. Grooves are formed in the arc-shaped outer edges of the plate hinges; a groove communicated with the groove is formed in the side surface of the plate hinge; the groove and the groove form an island-shaped boss on the side surface of the plate page; the peripheryof the island-shaped boss is sleeved with a sealing ring. A through hole is formed in the sealing ring; the through holes are filled with filling liquid, one section of the sealing ring is embedded in the groove, the other section of the sealing ring is located in the groove, an arc-shaped elastic piece is arranged in the groove, the middle of the arc-shaped elastic piece extrudes the sealing ring, the two ends of the ar