As a component of pipeline system, high Performance triple offset butterfly valve is widely used in may fields such as petroleum, chemical, metallurgy, and hydropower. It adopts to sealing structure, whose material is rubber, polytetrafluoroethylene, etc. Due to the limitations of structural features, it is suitable for high resistance, high pressure, corrosion resistance and wear resistance industries. The body and seat of valve are connected members. And the sealing surface of seat is welded with a temperature-resistant and corrosion-resistant alloy material.