News Center

 Pneumatic regulating valve refers to the pneumatic control valve, which takes the air source as the power, the cylinder as the actuator, the 4-20mA signal as the driving signal, and drives the valve by means of the accessories such as the electrical valve positioner, converter, solenoid valve and holding valve, so as to make the valve perform the regulation action with linear or equal flow characteristics, Thus, the flow, pressure, temperature and other process parameters of the pipeline medium can be adjusted in a proportional way.

    Pneumatic control valve has the advantages of simple control, fast response and intrinsic safety, and when used in flammable and explosive occasions, it does not need to take additional explosion-proof measures.

Working principle of pneumatic regulating valve:

    The pneumatic control valve is usually composed of pneumatic actuator and regulating valve connection, installation and commissioning. The pneumatic actuator can be divided into two types: single action type and double action type. There is a return spring in single action actuator, but there is no return spring in double action actuator. The single acting actuator can automatically return to the opening or closing state set by the valve when the air source is lost or the valve fails.

Action mode of pneumatic regulating valve:

    Air opening (normally closed) is when the air pressure on the membrane head increases, the valve moves towards the direction of increasing opening. When the input air pressure is reached, the valve is in full open state. In turn, when the air pressure decreases, the valve moves in the closed direction, and when no air is input, the valve is fully closed. Generally speaking, we call the air opening regulating valve as the fault closed valve.

    The action direction of air closing type (normally open type) is exactly opposite to that of air opening type. When the air pressure increases, the valve moves in the closed direction; when the air pressure decreases or does not, the valve will open or fully open. Generally speaking, we call the gas shut type regulating valve as the fault open valve.