The valve control is one of the most important instrumentation equipment and most of the time it acts as the final element of the loop controller. Usually, for precise control of flow fluids, a valve control is used, which can be in the form of a rose valve or a butterfly valve, which can be used in different types depending on the conditions. An operator or actuator is required to have a control though.
The most important operators for controlling the valve are as follows:
1) PNEUMATIC Pneumatic or pneumatic or diaphragm and electric actuators
2) Pneumatic or hydraulic
3) Electric or SOLENOID VALVE
Also, the valve control can equip the amount of fluid passing through the valve control faster and more accurately by equipping it with the POSITIONER positioner, which is a device for valve feedback and acceleration in the control command.
Another tool used in controlling I / P valves is I / P. Since the control signal commanded by the control valve can be of the type of 4-20 mA current, by adding this tool in pneumatic valves, the electric current signal can be converted into a pneumatic signal.