Pneumatic butterfly valve, as a component used to control pipeline flow and make and break, has been widely used in many fields such as petroleum, chemical industry, metallurgy, hydropower and so on. Among the known pneumatic butterfly valve technologies, the sealing forms of pneumatic butterfly valves include soft sealing and hard sealing. The sealing materials of soft sealing surfaces are mostly rubber, polytetrafluoroethylene, etc., while the hard sealing materials are mostly various alloys and metal materials. Metal sealed valves generally have longer service life than elastic sealed valves, but it is difficult to achieve complete sealing.

The pneumatic regulating butterfly valve has the smallest operating torque among all valves. It can be opened and closed quickly, powered by compressed air, through the mechanical transmission valve rod of the piston rack and gear, and rotate the valve plate 0~90o with the torque output from the angular stroke. It has simple structure, small volume, light weight, small flow resistance, large flow coefficient, and good sealing performance. Large adjustment range. It is the execution unit of instruments in the automatic control system;