Welded metal seal butterfly valve is suitable for use as a hoist or adjust medium of high temperature, high pressure, fire protection, thermal insulation pipes. Features a compact structure, small size, light weight, flexible, easy to use; 2, using a three-dimensional multi-level hard eccentric resilient seal structure, reliable sealing performance to achieve zero leakage; 3, the valve can not be blue, and the pipeline insulation wrap bring great convenience and aesthetics; 4, with a high temperature, high pressure, corrosion resistance, wear-resistant characteristics. The main parts of the material Part Name Material Body cast steel, stainless steel, chrome molybdenum steel and special steel material of the disc, alloy steel (hard chrome plating), stainless steel, chrome molybdenum steel and special steel material seals, valve stem wear-resistant material 2Cr13,1Cr13 stainless steel, chrome molybdenum steel flexible graphite packing