What are the working principles and advantages of pneumatic control valves?

 

With the development of industrial automation, the pneumatic control valve has also been widely used as a good actuator. This kind of control valve has the characteristics of reliable action and simple structure, which is of great significance for ensuring the safe operation of the system. The following is an in-depth analysis of the principle and advantage of pneumatic control valves in the chemical automatic control process.

 

 

The working principle and advantages of pneumatic control valve

The power source of the pneumatic actuated ball valve is compression control, and the pneumatic actuator is a pneumatic cylinder. The valve can be driven by the solenoid valve, converter, positioner, retaining valve and other components of the electric valve, and it can also realize the proportional adjustment of the switch, and then use various control signals to complete the pipeline medium temperature, pressure, flow and other parameter settings.

 

The pneumatic check valve has the characteristics of rapid response, simple control, and intrinsic safety, and no additional explosion-proof device is required. After the air chamber has a certain pressure signal, the membrane will have thrust, pulling the thrust plate, valve stem, push rod, compression spring, and valve core to move. After the valve core leaves the valve seat, the compressed air will circulate. After the signal pressure reaches a certain value, the valve will remain at the corresponding opening.

 

Pneumatic control valve has high reliability and simple structure, and there is no electric spark during operation. Therefore, its application range is very wide, and it can also be used in oil transmission stations with explosion-proof requirements.

 

 

Analysis of flow characteristics of control valve

The flow characteristics of the regulating valve include working flow and ideal flow. When the pressure difference between the inlet and the outlet is constant, the flow through the regulating valve is the ideal flow. This ideal flow has the characteristics of linear, parabolic, quick opening, and percentage.

 

In terms of adjustment quality, the chemical automatic control process mainly relies on the principle of characteristic compensation for production. The production of the system has strict regulations on the characteristics of the control valve. Based on this factor, when making a selection, it is necessary to analyze the control valve amplification factor in detail to prevent the adjustment coefficient from changing.

 

 In terms of flow characteristics, the flow rate of the regulating valve will change during use, which can easily cause oscillation problems. When the large opening operation is implemented, the regulating valve will appear slow, and it is easy to be adjusted in time and insensitive. Considering this factor, the linear flow control valve should not be used in a system with large changes.

 

 

Under the development of science and technology, chemical automatic control also puts forward higher requirements for regulating valves. This requires in-depth research on regulating valves to continuously improve the reliability and stability of regulating valves. Follow us to learn more about pneumatic actuated valves, electric actuated valves and valve actuator accessories.