Control Valve Study Material - Instrumentation Tools

Control Valve Positioners

The reason why a pneumatic control valve’s stem position corresponds linearly to the amount of air pressure applied to the

In some process applications, it is important that the control valve be able to completely stop fluid flow when placed

A completely different approach to packing is a device called a bellows seal : an accordion-like metal tube fastened to

Regardless of valve type, all stem-actuated control valves require some form of seal allowing motion of the stem from some

Valve actuators provide force to move control valve trim. For precise positioning of a control valve, there must be a

Disc valves (often referred to as eccentric disk valves, or as high-performance butterfly valves) are a variation on the butterfly

Electric motors have long been used to actuate large valves, especially valves operated as on/off (“shutoff”) devices. Advances in motor

A damper (otherwise known as a louvre) is a multi-element flow control device generally used to throttle large flows of

A different strategy for controlling the flow of fluid is to insert a rotary element into the flow path. Instead

Pneumatic actuators use instrument air pressure to apply force on the diaphragm to move the valve actuator and then to