Control Valve is a final element that is widely used in the industry. The Control Valve is used as the final element for regulating process variables such as flow, pressure, level, and temperature.
Following is the control diagram of the control valve in a process control loop.
Generally, the control valve is defined as a valve with an actuator that has an assembled local control system (positioner, regulator, multi-way valves, quick opening valves, transmitter, etc. ) that will receive the control signal by the process controller (PLC, DCS, etc) both electric and pneumatic systems.
The control valve can consist of various types of actuators, such as diaphragms, spring-diaphragms, pistons, motors, and so on. The following is an example of a construction diagram of a control valve.
The following is a schematic diagram of electric-pneumatic control valves.