Flange butterfly valve is a high-quality soft seal valve. It is mainly composed of the valve body, butterfly plate stem, operating mechanism, and other parts. It has the characteristics of a simple structure, good double-sided pressure bearing and corrosion resistance, light operating torque, and high reliability. Since the butterfly valve of this product adopts the centerline principle design, the spatial movement trajectory of the sealing surface is idealized. The sealing surfaces have no friction or interference with each other. In addition, the sealing material is properly selected, thereby improving the sealing performance and wear resistance of the butterfly valve. A reliable guarantee was obtained.