Top-mounted cast steel ball valve, integral valve body design, top-mounted pivot fixed support, flange structure, integral pivot fixed club, double-block discharge function, high-strength integral club structure. To ensure the precise positioning of the ball, the pivot adopts the anti-blowout protection structure, 2 groups of O-rings, plus the fireproof packing structure on the valve stem. Effectively prevent leakage and anti-corrosion, the bearings with low coefficient of friction can move the nylon sealed metal valve seat towards the ball due to nickel corrugated spring. Standard nylon and PEEK valve seats with excellent performance of inlet and outlet two-way sealing functions ensure the effective sealing sealant residents design under low pressure, and can live in sealants in emergency conditions, and the valve stem or valve seat is sealed using unique seat retractable technology. Replaceable clubs online. The torque of the stem sealing ring metal valve seat and corrugated spring is reduced to a minimum, which is convenient for the electric valve to operate the effective contact between the ball stem and the valve body, and the drive device platform and screw hole of the anti-static grounding equipment with superior performance can be equipped with the fire prevention function of the drive device at any time; When the valve seat is burned out or damaged, the metal valve seat automatically clings to the ball, and there is a small leakage between the valve seat and the ball.