The butterfly plate of the butterfly valve is installed in the diameter direction of the pipeline. In the cylindrical passage of the butterfly valve body, the disc-shaped butterfly plate rotates around the axis, and the rotation angle is between 0°and 90°. When the rotation reaches 90°, the valve is fully opened.

The Butterfly Valve with Pneumatic Actuator's power source is compressed air, the execution speed is relatively fast, and it is not easy to be damaged due to jamming , and manual operation is not required. It can not only be used as a shut-off valve, but also can be equipped with a valve positioner to realize the function of regulating and controlling the pipeline medium. There are two types of butterfly valves with pneumatic actuators, which are more safe.

The butterfly valve is simple in structure, small in size and light in weight, and consists of only a few parts. Moreover, it can be opened and closed quickly by rotating 90°, and the operation is simple. At the same time, the electric valve has good fluid control characteristics. When the butterfly valve is in the fully open position, the thickness of the butterfly plate is the only resistance when the medium flows through the valve body, so the pressure drop produced by the valve is small, so it has better flow control characteristics. The butterfly valve has two sealing types: elastic seal and metal seal. Elastic sealing valve, the sealing ring can be embedded in the valve body or attached to the periphery of the butterfly valve .