Because of its unique design structure and special hardening treatment of spheres and sealing rings, this series of metal-sealed ball valves are suitable for high temperature, high pressure, anti-corrosion and fast cut-off control of various fluids containing impurities such as solid particles, slurry and fibers. The ball valve has flexible action, small opening and closing moment, excellent sealing performance and long service life. It is widely used in petroleum, petrochemical, chemical, power plant, metallurgy and other industries.