This manual is intended to give an overview of the role of control valves in the behaviour of a process control loop. This overview consists the information on fluid behaviour and valve installed performance as well as the theory and practices of control valve sizing. Computer based simulation, design and sizing programs have been developing fast during past years and these are well in used by advanced control valve manufacturers to provide and maximize the benefits of process controlling. Control valve is a critical element in achieving the desired accuracy in process control. A full understanding of the interaction between the control valves and the process is in a key role in further development of the control performance. This is the area we believe this manual can provide valuable information and help the plant instrumentation, maintenance and process engineers. We hope this manual provides valuable aid and we appreciate any comments and suggestions for further improvement.
METSO (2011) Flow Control with Control Valves