Pneumatic Actuators

Valve Pneumatic Actuator Models: AW / GT / AT A valve pneumatic actuator is a control device that uses compressed air as its power source to drive valve opening, closing, or regulation through a cylinder. It uses air as the working medium, converting pressure energy into mechanical energy, outputting linear displacement or angular displacement to drive the corresponding type of valve. It mainly consists of a cylinder, piston (or diaphragm), spring (for single-action return), end caps, and stroke limiting mechanism, etc.By output motion type:Quarter-turn: Drives ball valves, butterfly valves, plug valves.Linear-stroke: Drives globe valves, gate valves, control valves.By action mode:Double-acting: Air-to-open, air-to-close.Single-acting (spring return): Air-to-open, spring-to-close, or vice versa — automatically returns to a safe position upon air failure.Technical characteristics of pneumatic actuators:Fast action speed with high response frequency; switching time is typically 0.1 to 0.5 seconds.Simple structure, small size, high power output per unit volume.Fire-proof and explosion-proof, intrinsically safe — especially suitable for flammable and explosive environments such as petrochemical plants and coal mines.However, they require an air compressor and air purification system, creating dependence on an air supply.Key selection considerations:Output torque/thrust must meet the valve's opening/closing requirements.Single-acting or double-acting mode must match the process safety failure position.Additional factors to confirm: air supply pressure (typically 0.4–0.7 MPa), ambient temperature, explosion-proof and ingress protection rating (explosion-proof types are flameproof or intrinsically safe designs), and the configuration of accessories such as solenoid valves, limit switches, and positioners.