Control valves are widely used in process industry to control different parameters of a process service such as - pressure, temperature, flow, level etc.
There are different types of valves which can be used as control valves. A suitable type of valve is usually selected based on the process requirements.
Furthermore, applications of these control valves will be determined by what kind of process control needs to be implemented - for example whether control over pressure, temperature or flow is desired.
Control valve sizing calculations have a significant importance in process design, as a properly functioning control mechanism can ensure the process works as designed. For more details on control valve sizing, check out the theory behind sizing calculations and more detailed control valve sizing guidelines for you to get started.