The difference between electric valve and pneumatic valve

The operating force distance of pneumatic valves is larger than that of electric valves. The switching speed of pneumatic valves can be adjusted. The structure is simple and easy to maintain. Due to the buffering characteristics of the gas itself during the operation, it is not easy to be damaged by jamming. However, it must have a gas source, and its control system is also more complicated than electric valves. Pneumatic valves are responsive, safe and reliable. Many factories with high control requirements set up compressed air stations specifically for pneumatic instrument control components. The power source of the pneumatic valve actuator is the air source, which comes from the air compressor. The positioner is used to convert the electrical control signal into a pneumatic control signal, and drives the pneumatic actuator to adjust the valve position.

The power source of the electric valve actuator is the power supply. If the circuit board or motor fails, sparks are likely to occur. Therefore, it is generally used in situations where the environment is not high and there is no danger. Comparing the regulation performance of pneumatic actuators and electric actuators, pneumatic actuators respond faster and are more suitable for use in regulating conditions. Therefore, manufacturers of regulating valves also produce pneumatic actuators to match them.

The adjustment response speed of electric actuators is not fast enough. Taking ROTORK as an example, the adjustment times of adjusting actuators are only 1,200 times per hour, so pneumatic actuators are used more often on control valves than electric actuators.

The essential difference between electric valves and pneumatic valves lies in the use of different driving devices, that is, actuators, while the regulating valve itself has no difference. Cooperating with different actuators mainly depends on the working conditions. For example, in chemical industry and other explosion-proof situations, pneumatic valves are mostly used because they have high safety requirements and are cheap. They can be connected to the bus with an intelligent positioner, and the control method is simple.