Pneumatic valve actuators are mainly used in nuclear power plants or power plants because a stable, smooth and slow process is required in high pressure water systems. The advantages of electric actuators are high stability and fairly stable thrust that can be applied by users. Only hydraulic actuators can achieve such a large thrust, but the cost of hydraulic actuators is much higher than that of electric ones. The anti-deviation ability of the electric actuator is very good, the output thrust or torque is basically stable, it can well overcome the unbalanced force of the medium, and achieve the precise control of the process parameters, so the control accuracy is higher than that of the pneumatic actuator. high. If it is equipped with a servo amplifier, it can easily realize the exchange of positive and negative effects, and can also easily set the state of the off-signal valve position (persistent/full open/full close), and when it fails, it must stay in the original position, which is pneumatic The actuator can't do it, and the pneumatic actuator must use a combined maintenance system to keep it in place.
The main disadvantages of electric actuators are:
The structure is more complex, and it is easier to fail, and because of its complex nature, the technical requirements for on-site maintenance personnel are relatively higher; the operation of the motor will generate heat, if the adjustment is too frequent, it will easily cause the motor to overheat and generate thermal maintenance. It will also increase the wear of the reduction gear; there is also a slow operation, which takes a long time to output a signal from the regulator to the corresponding position of the regulating valve, which is not as good as pneumatic and hydraulic execution. place of the device.
The actuator and regulator of the valve pneumatic actuator are the same as a whole, and the actuators are of two types: diaphragm type and piston type. The piston type is suitable for occasions requiring large thrust due to its long stroke; while the diaphragm type has a small stroke and can only directly drive the valve stem. Because pneumatic actuators have the advantages of simple structure, stable and reliable action, large output thrust, and safety and explosion-proof, they are widely used in chemical, power plant, oil refining and other production processes with high safety requirements.
The main advantages of pneumatic actuators: they can accept continuous gas signals, output linear displacement, and some can output angular displacement after being equipped with a rocker arm; they have positive and negative effects; the moving speed is large, but the speed will change when the load increases Slow; the output force is related to the operating pressure; the reliability is high, but the valve cannot be maintained after the air source is interrupted; Explosion-proof function.
The above is the relevant content about the comparison of the advantages and disadvantages of electric valves and pneumatic valves. Assuming you have a demand for our company's products, you are welcome to contact the online customer service to inquire about quotations and other information. You are also welcome to come to our company for inquiries and sincerely invite you to cooperate. !
