Pneumatic actuator operated butterfly valve is composed of pneumatic actuator and butterfly valve. In general, pneumatic actuator operated butterfly valves operate similarly to ball valves. Both are quarter-turn valves for stopping, regulating, starting, and throttling flow, but the butterfly valve is far lighter and require less structural support. The pneumatic actuator operated butterfly valve operates on the idea that compressed air enters the actuator to drive the piston, which then rotates or lifts the torsion shaft to drives the stem.