What is the difference between an electric actuator and a pneumatic actuator?

Actuators generally include pneumatic actuators, electric actuators, and Hydraulic Actuators. The general definition of actuator is: a driving device that can provide linear or rotary motion, use the driving energy and under the action of the control signal, automatically operate some equipment and devices, control its switch and adjustment, and replace manual operation. The actuator is the terminal control unit in the process control industry, which usually consists of a valve and an actuator. Electric actuators are controlled by various currents, while pneumatic actuators use air pressure to control their operation.
In the process of production in a variety of industries, actuators are an indispensable kind of machines, usually according to the application environment and application industry can be divided into two categories, that is, electric actuators and Pneumatic Actuators, the functions of these two actuators are almost the same, but from other aspects of comparison is quite different, the following is a list of differences in several aspects.
One. How easy it is to get the drive source
(1) Electric actuator: The drive source is the power supply, whether it is a three-phase power supply or a single-phase power supply, which is very convenient to obtain in the industrial site.
(2) Pneumatic actuator: the driving source is the gas source, which needs to be specially equipped with the gas source station and laying the pipeline, and the construction is more cumbersome and the budget is increased. The air source is generally compressed air, so it is also equipped with a large air compressor.
Power is readily available at all types of industrial sites. For some small equipment, it is more convenient to use electric solutions (usually small equipment is without compressed gas, such as: plate press, shield machine, etc.)
Two. energy conservation
(1) Electric actuator: only when changing the opening of the Control Valve, the motor needs to be driven, and the motor is powered off when the required opening is reached. In standby mode, only a small amount of power is required to maintain the operation of the control unit.
(2) Pneumatic actuator: There needs to be a certain air pressure in the whole Control Valve operation and standby state, and when the air pressure drops, the compressor will run and pressurize.
In general, electric actuators are more energy-efficient than pneumatic actuators.Three. Differences at the technical level
The obvious difference between pneumatic actuators and electric actuators is their technical differences, the overall structure of pneumatic actuators is unified, so its load capacity is better, and because it uses gas as the power source, it is particularly suitable for high torque output; The size of the electric actuator is relatively small, and the structure is simpler than that of the pneumatic actuator, so from the technical point of view, it is easy to equip and the power drive is also very flexible.
Four. Differences in the usage environment
The difference in the use environment is also one of the important differences between pneumatic actuators and electric actuators, this difference is also caused by the difference between them in structure and energy. Electric actuators, on the other hand, have environmental requirements, and they must be strictly complied with in any case.
From the basic characteristics of electric actuators, we can know that there is a big difference between electric actuators and pneumatic actuators, among which the three obvious differences are their structure, technical level, use environment, etc., but these will not affect the use, because the fields of application of these two actuators are different.
Summary: The electric actuator will have more advantages in the selection, it is compact in structure, small in size, compared with pneumatic actuators, the structure of electric actuators is relatively simple, the energy is convenient, there is no danger of "air leakage", and the reliability is high. The performance of the electric valve will be higher than that of the pneumatic one, after all, it relies on the motor to drive the valve, so its torque will be greater. This can adapt to more working conditions, and at the same time, the electric valve is no longer limited to the quarter-stroke valve in terms of valve type, but can be used on the straight-stroke valve such as gate valve and globe valve.