Executive agencies can be divided into Electric actuator,,Pneumatic actuators, electro-hydraulic actuators, gas-liquid actuators. This is the most concerned with electric actuators and pneumatic actuators, but there is a big difference between them. There are great differences in performance and price, which affect the choice of users.
1. Main considerations for implementing agency selection
The main considerations for actuator selection are: 1 reliability; 2 economy; 3 smooth operation, sufficient output torque; 4 simple structure, easy maintenance, etc.
2.Electric actuators and comparison of pneumatic actuators：
The biggest shortcoming of pneumatic actuators is the need to set up a gas source station, which increases the huge cost; the drive source of the electric actuator is available anywhere. Generally need 380V or 220V power supply.
（2）Reliability and maintainability
The intelligent integrated electric actuator is free from opening and debugging. The superior performance of the product is obvious. Whether it is the introduction of foreign technology or the stability and reliability of the imported actuator, it is very high, and it can be repaired within 3-5 years. Its reliability. Even far exceeds the pneumatic actuator。
The pneumatic actuator response time is slightly faster than the electric actuator, ie the travel time is slightly shorter than the electric actuator.
（4）Thrust and stiffness
The thrust range of the electric actuator on the thrust is slightly larger than that of the pneumatic actuator. The stiffness is equal.
Pneumatic actuators must be equipped with a valve positioner, plus the air supply, the cost will be much higher than the price of the electric valve (the imported pneumatic valve positioner is similar to the imported electric actuator; domestic locator and The price of domestic electric actuators is slightly lower, but with the air source, the price of pneumatic valves will be higher than that of electric valves.
The “Pneumatic Actuator + Valve Positioner” has an explosion-proof rating of the intrinsically safe type, with the highest rating being Exdib II CT6; the electric actuator is explosion-proof and the highest rating is Exdib II CT4. In summary: Pneumatic actuators are slightly higher than electric actuators. In the fields of metallurgy, electric power, water conservancy and building materials, electric actuators are used. In the chemical and petroleum petrochemical pipelines, pneumatics are the mainstay.