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 outer circle of the butterfly plate of the pneumatic butterfly valve adopts spherical shape, which improves the sealing performance and prolongs the service life of the valve. Zero leakage is still maintained after more than 50000 times of opening and closing under pressure. The sealing elements can be replaced, and the sealing is reliable to achieve two-way sealing. The butterfly plate can be coated according to user requirements, such as nylon or PTFE. The valve can be designed as flange connection and wafer connection. The driving mode can be manual, electric or pneumatic.