The working principle and selection method of pneumatic actuator

The actuator and adjusting mechanism of the pneumatic actuator are a unified whole, and the actuator has a film type, a piston type, a fork type and a pinion and rack type. The piston type has a long stroke and is suitable for occasions requiring greater thrust; The film stroke is small, can only directly drive the valve stem.

Principle of single acting pneumatic actuator:

It is driven by the air source power to complete the opening action, and the opening process is basically similar to that of the double-action pneumatic actuator, but the reverse nozzle of the single-action pneumatic actuator is the exhaust hole and the compressor is not the entrance. The closing action of the single action pneumatic actuator is completed by the spring power driven valve.

Principle of double acting pneumatic actuator:

It is driven by the air source power to complete the switching action, compressed air from the nozzle of the pneumatic actuator into the pneumatic actuator, the gas will push the piston to move to both ends, and drive the gear on the rotating shaft through the rack to rotate, thus opening the valve. When the pneumatic actuator is closed, the air source enters from the reverse nozzle, pushing the piston to the middle movement, driving the valve to close.

The actuator and regulating mechanism of the pneumatic actuator are unified as a whole, and the parts of the actuator can be selected as film, piston or rack and pinion, of which the rack and pinion are more commonly used. The pinion and rack actuator has a compact structure, large output driving force, stable and reliable action, and is one of the more balanced performance among the three actuator components.

Structural and functional characteristics:

1. Compared with the actuator of the same specification structure, the weight is lighter.

2. positive and negative function, the output force is related to the operating pressure.

3, large output power, explosion-proof function, high reliability.

4. compact double piston gear, rack type structure, accurate mesh, high efficiency, constant output torque.

5. the inner surface texture is hard, strength, high hardness, low friction coefficient, flexible rotation, long service life.

6. The assembly hole of the bottom shaft of the pneumatic actuator is double square, which is convenient for linear or 45° Angle installation of the valve with square rod.