Customized pneumatic actuator with top mounted handwheel
Advantages of pneumatic actuators and their common three types
The advantage of pneumatic actuator is that even if the leakage will not pollute the environment, it has good adaptability to the working environment and will not be affected by the harsh environment such as inflammable, explosive, strong magnetic, strong radiation, etc. It can reset the valve to the preset safe position in the power supply, oil source and signal to protect the valve system. Due to the air compression, the stability of pneumatic movement is slightly poor.
According to its working principle, pneumatic actuators can be divided into three types: ordinary type, quick closing type and regulating type
Ordinary type
Air source treatment triple element (including filter, pressure reducing valve and oil mist) and solenoid valve are a basic form. When the valve needs to be opened, the solenoid valve enters the actuator chamber A through the solenoid valve (the gas in the actuator chamber B is discharged into the atmosphere through the solenoid valve), pushes the left side of the piston and opens the valve. When the valve needs to be closed, the solenoid valve loses power, the pressure gas enters the chamber B of the actuator through the solenoid valve (the gas in the chamber A of the actuator is discharged into the atmosphere through the solenoid valve), pushes the piston to the right, and closes the valve. When the actuator is a single function, the solenoid valve selects the two position three-way type. When the actuator is of dual function, the solenoid valve shall be of two position five way type; when the valve is de energized to maintain its position, the solenoid valve shall be of three position five way type when it is of air selection.
Quick closing type
Single acting actuators are usually used for quick valve closure. The quick opening pneumatic actuator is to add a quick exhaust valve on the basis of the ordinary pneumatic actuator to quickly discharge the gas in chamber A and speed up the closing of the actuator. When the valve needs to be opened, the solenoid valve is energized, gas enters the actuator chamber A through the solenoid valve and quick exhaust valve, the compression spring pushes the left side of the piston, and the valve opens. When the valve needs to be closed, the solenoid valve loses power, and the gas is cut off. Under the pressure of the spring, A rapidly discharges the gas in the chamber through the quick exhaust valve, and the piston right travel valve quickly closes.
Regulating type
The regulating pneumatic actuator can receive current, voltage or air flow signals from the system (current signals are common). The opening of the valve can be adjusted according to the size of the signal. The opening of the valve can be fed back to the system in the form of signals according to user requirements, forming a closed loop control. An adjustable pneumatic actuator is formed by replacing the solenoid valve in an ordinary pneumatic actuator with an electric pneumatic positioner or a pneumatic pneumatic positioner actuator. As the default values of factory parameters set by locators from different manufacturers are different, they should be adjusted according to user requirements.
