During setting up a fluid control system, there are dozens of different types of valves to choose from. Each serves a specific purpose, but keeping them straight can get confusing. Many people have problems with the difference between control valves and on-off valves. On-off valves and control valves are similar in some senses, but the difference lies in their degrees of control. Where control valves can be very precise, on-off valves can do exactly what their name suggests i.e, turn on or turn off. Control valves are used in situations where specific control over a piece of a system is needed. Control valves and on-off valves serve different purposes depending on the degree of control for the system. An on-off valve is a much less-precise instrument than the control valve. It either allows for unimpeded flow or it shuts off flow completely. There are a couple of different styles of on-off valves, including Gate, Butterfly, Globe, Ball and Plug valves. On the other hand, Control valves are more precise. Control valves are used to maintain a process variable as close as possible to the desired set point. Controller set points are typically flow rate and pressure. Control valves are used to control fluid flow by varying the size of the flow passage as directed by a signal from a controller.
SIGMAFLOW offers state-of-the-art Control valves as below :
- Automatic control valve Diaphragm actuated
- Plunger flow control valve