Pneumatic actuator
advantage
1. Accept continuous gas signal and output linear displacement (continuous electrical signal can be received after power/gas conversion device). Some can be equipped with angular arm displacement after outputting the rocker arm.
2. There are positive and negative functions.
3. The moving speed is large, but the speed will be slower when the load increases.
4. The output force is related to the operating pressure.
5, high reliability, but the valve can not be maintained after the gas source is interrupted (can be maintained after the retaining valve).
6. Inconvenient to implement segmentation control and program control.
7, easy maintenance and adaptability to the environment.
8, the output power is large.
9, with an explosion-proof function.
Disadvantage
1. The control precision is low. The double-acting pneumatic actuator can't return to the preset position after the air source is cut off.
2. The single-acting pneumatic actuator can return to the preset position by the spring after the gas source is cut off.
Electric actuator
advantage
1. Easy access to energy, fast transmission signal, and long signal transmission distance for centralized operation control.
2. The accuracy and sensitivity are relatively high. It is easy to operate with other electric adjustment instruments, and the wiring is simple to install.
3. The effect proves that the electric actuator has good anti-deviation ability, and the output torque or thrust is basically constant, which can overcome the imbalance force of the medium and ensure the precise control of relevant process parameters, so the product control The accuracy is slightly higher than the pneumatic actuator.
4. If equipped with a servo amplifier, it can easily realize the interchange of positive and negative effects, and can also easily set the status of the signal valve position. If it is in the event of a fault, it must stay in the original position. This capability is not possible with pneumatic actuator products. This is achieved because the pneumatic actuators must be equipped with a combined protection system to achieve the retaining function.
Disadvantage
1. It is only suitable for places where the explosion-proof requirements are not high and the gas source is lacking. The structure is relatively complicated, the thrust is small, and the average failure rate is higher than that of the pneumatic actuator. However, due to the complexity of the structure, the technical requirements for the field maintenance personnel are relatively high.
2. The motor will generate heat. If the adjustment frequency is large, it will easily cause the motor to overheat and increase the wear of the reduction gear.
3, there are slower running, from the regulator output signal, to the response of the valve to move to the specified position, often more time-consuming, the above is less than the performance of pneumatic or hydraulic actuators.
January 05, 2022
