For the ball valve, the ball body rotates around the vertical axis of the valve body by 90°to open or close the passageway. High-class ball valves are provided with the safety structures for preventing fire, static, valve rod blowout, etc., and the ball valves installed on pipelines are mainly used to cut off or distribute medium or change medium flow direction. Generally, ball valves can be widely applied as the medium cutoff-connection control equipment in the industrial fields of petroleum and natural gas storage & transmission, chemical product, metallurgy, papermaking, food, shipbuilding, etc., and the ball valves configured with pneumatic or electric actuators, etc. can be used to realize remote operation. Less