Device used to open/close or control the valve. Key types include electrical, hydraulic and pneumatic. Movement may be quarter-turn or multi-turn. Actuators may be used when (i) valves are remotely located (eg, on pipelines) (ii) valves are located in hazardous areas (iii) manual operation would be time-consuming (eg, with larger valves)
Valve that is used to control the flow of air. Flows are normally small, so solenoid valves are suited.