The FWB Guide to Valve Types
16 February 2021
Valves are pipe fittings used to control the flow of fluids, such as liquids, gases, and slurries, through a pipe system. This is achieved by opening, closing, or sometimes partially obstructing the pipe to control the flow of the fluid(s).
At FWB, we stock a wide range of different valves, such as ball valves, check valves and butterfly valves available in various materials such as brass, stainless steel and ductile iron. Below are some of the more common valve types and their uses:
Ball Valves – Ball valves feature a metal ball which is bored through the centre. The valve is open when the ball’s hole lines up with the flow of the fluid running through the pipe and is closed otherwise.
Non-Return (Check) Valves – Non-return, or ‘Check’ valves are designed to prevent ‘back-flow’. They allow fluid to flow in one direction, but if the flow becomes reversed, it is prevented from travelling back up the pipe by a hinged disc (on a ‘swing’ check valve).
There are other types of non-return valves, including spring, ball and piston. They are designed for specific environments, but all serve the same purpose.
Globe Valves – the Globe valve, so called because of it’s (usually) spherical shaped body is widely used in plants where the flow of liquid/gas may need to be “throttled” to regulate the flow of the media. Unlike the Gate Valve, Globe valves have a disc (or plug) that sits in a spherical seat. As the valve seat is parallel to the line of flow, by turning the handwheel on a manual Globe valve, the rate of flow can be adjusted. Compared to Ball Valves and Gate Vales, Globe valves suffer a higher pressure loss, due to the flow of liquid having to change direction as it flows through the valve.
Gate Valves – Gate valves feature fully open and fully closed positions and are designed to completely shut off the flow of fluids through a pipe system when closed. When open, fluids will be allowed to flow through the system unrestricted. Although there is limited scope, they are not generally designed for ‘throttling’.
Needle Valves – Needle valves allow fine control over the flow of fluids through a system, giving engineers the ability to stop, start and regulate flow and pressure.
Butterfly Valves – Butterfly valves are quarter-rotational valves that feature a mounted disc that can be turned using a handle. They are very quick to open and close.
Solenoid Valves are used when the control of fluid or air needs to be controlled automatically.
There is a large variety of solenoid valves that are designed to suit specific applications. In brief, they are a valve that opens or closed by way of an actuator being either energised or de-energised. There are a large variety of solenoid valves, with different port configurations, body materials and types of valve operation to suit many requirements.
To browse our range of valves, please click here.