The pneumatic double-clamp type hard-sealing butterfly valve adopts a precise j-shaped elastic sealing ring and a three-eccentric multi-level metal hard sealing structure, and is widely used for treating gold, electric power, petrochemical industry, water supply and drainage and municipal construction of the medium temperature and 425 DEG C, And is used for regulating flow and carrying off fluid. Characteristics of Pneumatic clamping hard Seal Butterfly Valve 1. The pneumatic clamping hard seal butterfly valve adopts three eccentric sealing structure, and the valve seat and butterfly plate have almost no wear and tear, so it has the sealing function of more and more tight. 2. The sealing ring is made of stainless steel, and has the dual advantages of metal hard seal and elastic sealing, and has the characteristics of corrosion resistance, long service life and the like, both at low temperature and high temperature. 3. The sealing surface of the disc is made of hardfacing cobalt-based hard alloy, and the sealing surface is resistant to wear and has long service life. 4. The large size butterfly plate adopts quilting structure, which has the advantages of high strength, large overcurrent area and small flow resistance. 5. The valve has two-way sealing function. The valve is not limited by the flow of medium during installation, and is not affected by the space position. It can be installed in any direction. 6.The drive unit can be installed at multiple stations (rotated 90 ° or 180 °) for ease of use by the user The gas butterfly valve is mainly divided into hard seal gas butterfly valve and rubber soft seal butterfly valve according to different sealing forms.