The pneumatic actuators executive branch and adjusting mechanism is unified whole, its enforcement agencies have film type, piston, fork type and gear rack type. Piston stroke long, apply to require a larger thrust circumstance; And the film type trip is small, can only direct drive the valve stem. Fork type of pneumatic operation instruments torque, space is small, torque curve more in line with the characteristics of torque curve valve, but not very beautiful; Commonly used in large torque on the valve. Super-modulus gear type pneumatic actuators have simple structure and action of the stable and reliable, and the security explosion-proof etc, and in the power plants, chemical, oil refineries to safety requirements of high production process is widely used.

Advantage

1, accept the breath of the continuous signal, the output linear displacement (plus electric/gas switching device, can also accept continuous electrical signal), some with rocker, angular displacement output.

2, there are, reaction function.

3, mobile speed, but the load increases becomes slower.

4, output force and the operating pressure.

5, high reliability, but air after interrupting the valve can not keep (plus the position after valve can keep).

6, inconvenience piecewise control and realize process control.

7, simple maintenance, adaptability to the environment of good.

8, output power is bigger.

9, has the explosion protection function.

Classification

Actuator according to the energy form divided into pneumatic, electric and hydraulic 3 kinds big, they have different features, suitable for different occasions. The pneumatic actuators is a category of actuators. The pneumatic actuators can also be divided into single function and DOUBLE role two types: the implementation of the switch movements are through the air to drive the implementation, called DOUBLE ACTING (DOUBLE function). SPRING RETURN (single function) switch action only open action is air drive, and shut action of the SPRING RETURN.