Like other instrumentation components, the connection sizes of valves in process instrumentation are characteristically small, ranging from 1/8 inch (3.175 mm) to 1 inch (25.4 mm).
In this blog post, we’ll discuss the different valve types, which include the following:
- Ball Valves are quarter-turn valves which use a hollow, pivoting ball (a.k.a. floating ball) to control flow through.
- Bonnet Needle Valves make fine and precise adjustments in the amount of fluid or gas flow.
- High Performance Actuated Ball Valves automatically generate torque that is transmitted to an output shaft which is connected to the valve's stem rotating the valve's ball in opening or closing the orifice to allow or block the media flow.
- Plug Valves have a one-piece top-entry design and are very similar to one-piece, top-entry ball valves.
- Toggle Valves allow the control of flow via a directional toggle switch.
- Metering Valves are designed to provide metered stability and accuracy of flow rates in instrumentation, laboratory equipment and analyzers where accurate flow control is necessary.
- Check Valves are one-way safety valves designed to prevent backflow. There is a backflow preventer that is held open by the forward flow.
- Excess Flow Valves are like check valves. Excess flow valves incorporate a spring-loaded shut-off which will only close based on specified conditions when the flow through the valve exceeds a predetermined closing flow rate.
- Relief Valves are designed to control a system’s pressure. Relief valves open in direct proportion to the increase in systems pressure.
- Bleed Valves are used in process control applications to shut off the upstream pressure and bleed off excess fluid or pressure in the system.
- Metering Ball Valves play an integral part in many process systems. They incorporate both metering and shut-off functions in one unit that combines an accurate micro-meter control mechanism for gases and liquids, along with a sealing device in a single unit.
- Manifold Valves are a type of process connection system that connects one or more block or isolation valves that provide venting, isolation, and equalization for a variety of pressure measurement applications.
- Valve Packing uses some form of packing as a sealing mechanism to prevent leakage from the space between the stem and the bonnet.
Learn more about how these valves are used in this BluPrint called, “Evolution of Process Instrumentation Valves into the IoT Era.”