PLT's forged metal seal ball valve is widely used in petrochemical and coal chemical industries because of its small fluid resistance, convenient operation, fast opening and closing, good sealing and high reliability. The movement, stop or direction in the process of fluid transmission are determined by the opening and closing of ball valve, so the sealing of ball valve is very important, safety and stability determine the normal operation of the whole transmission device. Due to the corrosive and large particles of chemical raw materials in petrochemical, coal chemical and other industries, it puts forward higher requirements for the valve's high pressure resistance, high temperature resistance, corrosion resistance and friction resistance. The traditional soft sealing pair is difficult to meet the requirements, Therefore, the high pressure metal hard seal ball valve with metal seat is more suitable for petrochemical and coal chemical industry. The metal hard seal ball valve uses spring preload and fluid ballast to make the seat and ball contact closely, so as to achieve the sealing of the ball valve. We provide full solution of metal seal ball valves which are applicable to sever medium and working conditions.