The SM5 series high pressure ball valve adopts trunnion mounted, three-piece and bidirectional sealing structure. For all parts, such as body, body ends, ball, stem, seats and so on are forged and via precisely machining. These series ball valve possesses high pressure-bearing level, the single or double piston effect structure can be accessible according to actual working conditions. Nominal size can be up to DN600, and nominal pressure rating can be up to ANSI2500. Equipped with the soft seal seat or metal seal seat, the seat leakage rates meet requirements of API598 and API6D standards, which allows this series valve to be used in long-distance conveying pipeline, coal chemical industrial or other fluids at the bad conditions for a long time.