Control Valve Overview
Control Valves are valves used to control conditions such as Flow, Pressure, Temperature and Liquid Level. The range of valves used for these purposes is extensive and varied, so this section is only representative of the type of valves that we can supply, but is by no means complete.
The accuracy of control is determined by the type of control valve selected, the correct calibration of the type of positioning device and correct valve “sizing”. “Sizing” control valves is essential and relies on obtaining and inputting all of the various application data…pressure, temperature, SG, viscosity and the min/normal/max flow control ranges. We have excellent sizing programs to assist us with these calculations.
We have decided to present this section by starting with the simplest type of self acting valves and progressing through to more sophisticated valves that are generally operated by a pneumatic actuator and positioned by a pneumatic or electro-pneumatic positioner, which receives a 3-15 psi or 4-20mA signal from a PLC or other control instrument.