Butterfly valve featuring two-way metallic seal of bellows

The invention relates to a butterfly valve, in particular to a butterfly valve featuring two-way metallic seal of a bellows, comprising a valve body, a vale seat, a butterfly plate, a valve rod which is in leakage connection with the butterfly plate and an operation mechanism which drives the valve rod to rotate; wherein, a sealing working surface of the butterfly plate in circumferential direction is a conical inclined plane; the working surface of the valve seat is accordingly an inclined plane; the butterfly valve is characterized in that a suspension type structure is formed between the periphery of the valve seat and the inner wall of the valve body; a ring-shaped convex plate is arranged at the inner wall of a channel of the valve body; the end surface of the valve seat is connected with the end surface of the ring-shaped convex plate by the bellows; the outer layer of the bellows is communicated with the clearance between the valve seat and the inner wall of the channel of thevalve body; the inner laye