Advantages and disadvantages of pneumatic valves and electric valves
The action torque of the pneumatic valve is larger than that of the electric valve. The switching speed of the pneumatic valve is adjustable. Simple structure and easy maintenance. Due to the cushioning characteristics of the gas itself, it is not easy to be damaged due to jamming during the action. It has an air source, and its control system is also more complicated than an electric valve.
Pneumatic valves are sensitive and reliable. Many plants with high control requirements set up compressed air stations for pneumatic instrument control components. Electricity is electricity.
The function of the pneumatic valve positioner is to receive the output signal of the pneumatic regulator, and then generate a pneumatic signal proportional to the output signal of the regulator to control the pneumatic control valve.
There are many types of pneumatic valve positioners. According to its working principle, it can be divided into two categories: displacement balance type and force (moment) balance type.