The ball of the soft seal pneumatic ball valve is carbon steel chrome plated, the seal ring is extruded PTFE or RPTFE, and the contact surface between the valve seat seal ring and the ball is conical. Taking the pneumatic ball valve process produced by most manufacturers as an example, when closing the pneumatic ball valve, the length of both ends of the ball is 58mm and the large end of the cone plane of the valve seat seal ring Ф 58.5mm coaxial. When the valve cover is fastened, the sealing ring is pressed evenly in the circumferential direction, that is, the deformation on the circumference of the sealing ring is the same. However, in fact, it rarely achieves the ideal state. The position of the ball is often caused by the position error of the ball and the connecting groove of the valve stem, the position error of the valve stem head, the error of the valve block and the small clearance of the connecting groove. After the valve cover is fastened, the circumference of the seal ring likes to squeeze to form a boss. The larger the compression amount, the more serious the boss will be, and the opening and closing torque of the pneumatic ball valve will also be greater. Even if the square hole of the handle is damaged, it still cannot be started. The formed boss will cause uneven movement and leakage during the opening and closing process.

7、 Long term outdoor storage will lead to corrosion of valve body and components, which can not be used normally. The ball valve shall be rain proof, waterproof and moisture-proof when stored, and the flange cover shall be tightly covered. The valves stored for more than 12 months shall be retested during use to ensure stable performance.