The invention discloses a hard sealing double eccentric
butterfly valve for an S-shaped elastic double O-shaped
metal sealing ring, which comprises a double eccentric butterfly plate, a valve body and a valve rod and is characterized in that the S-shaped elastic double O-shaped
metal sealing ring is placed between the double eccentric butterfly plate and the valve body, and a regulation mechanism consisting of a pressing ring, a control ring, a positioning plate, a regulating screw bolt and a
retainer ring is arranged at the sealing ring part. The S-shaped elastic double O-shaped
metal sealing ring structure is adopted, so the problem of complicated sealing structures or single static sealing design structures caused by the dynamic and static sealing
coupling is effectively solved, and the sealing structure is simplified. The sealing ring part is provided with a regulating structure, the elastic deformation quantity and the deformation direction of large and small elastic O-shaped metal sealing rings can be simultaneously regulated, the elastic deformation quantity and the elastic force can be effectively provided, the reliability of the sealing performance is improved, the deformation caused by the heat expansion and cold contraction of materials can be obviously and perfectly compensated particularly in high and low temperature application occasions with sharp temperature change, and the internal sealing performance of the
butterfly valve is ensured.