There are many factors affecting the sealing performance of pneumatic ball valve, such as the coaxiality between the pneumatic ball valve, upper valve stem and lower valve stem. The roundness and smoothness of the ball, the roundness of the 90 degree conical surface of the valve seat, the preload of the O-ring of the valve seat, the preload of the compression spring, etc. Therefore, how to solve these problems has become the key to the sealing of pneumatic ball valves.

2. Assemble the valve after maintenance. (1) Before assembly, all elements of the valve shall be cleaned and inspected. The assembly sequence shall be from bottom to top. The added gasket shall be coated with grease and the added filler shall be filled evenly. (2) All fastening bolts and packing shall be coated with grease before assembly to facilitate the next maintenance and lubrication.