Regulating valve, also called as control is a kind of valves which receive control signal and change flow of fluid with the help of motive power. Regulating valve consists of actuator and valve. Based on motive power, regulating valve can be classified into pneumatic regulating valve(using compressed air), electric regulating valve(using electricity) and hydraulic regulating valve(useing pressure of liquid medium).
Regulating valve has a lot of varieties. The most common used regulating valve is straight regulating valve, straight two-way regulating valve, butterfly regulating valve and ball regulating valve, etc. Choosing regulating valve should be based on the following situations:
(1)Structure
Consider characteristics of fluid and unbalanced force.
(2)Wearing-resistance
For medium having high concentration of pellet, inner materials of valve should be hard.
(3)Corrosion-resistance
Valves which have simple structure are suitable for corrosive medium.
(4)Tempaerature & pressure of medium
When medium having high temperature and high pressure which change a lot, it should use the valve whose materials of core and sead having small changing temperature and pressure.
(5)Avoid flash and cavitation
Fluid medium can cause flash and cavitation. During utilization, flash and cavitation form vibration and noise, reducing long service life of valve. For that, choosing valve should avoid flash and cavitation.
