How Control Valve Works - Animation
Any Valve can be turn in to a Control Valve simply by adding an Actuator.
Valve actuates in response to a signal move about to a desired position using an outside power source.These outside power sources may be in the form of pneumatic,electronics or hydraulics.
Pneumatic Actuators move a valve position by converting air pressure into linear or rotary motion.
Linear motion devices opening close valves such as Gate,Globe,Diaphragm,and others with a sliding stem to control the position up the flow control element.
Rotary Motion devices typically operates quarter turn type valve such as ball,plug,and butterfly.A quarter turn valve is one which can be opened 100 percent by turning the flow control element just 90 degree.
There are three types of Pneumatic Actuators