Rotary valve

From Wikipedia, the free encyclopedia

A rotary valve is a type of valve in which the rotation of a passage or passages in a transverse plug regulates the flow of liquid or gas through the attached pipes. The common stopcock is the simplest form of rotary valve. Rotary valves have been applied in numerous applications, including:

• Changing the pitch of brass instruments.
• Controlling the steam and exhaust ports of steam engines, most notably in the Corliss engine.
• Periodically reversing the flow of air and fuel across the open hearth furnace.
• Loading sample on chromatography columns

Contents 1 Use in brass instruments 2 Use in industry 3 Use in chromatography 4 See also

[edit] Use in brass instruments

In the context of brass instruments, rotary valves are found on French horns, trumpets, trombones, and tubas. Many European trumpet players tend to favor rotary valves. The valve on trombones with an f-attachment is a rotary valve.

Joseph Riedlin is credited with the rotary valve for brass instruments in 1832.

[edit] Use in industry

In industry, a rotary valve (which can also be called Airlock) is often used to enter or extract material from two chamber with different pressure level.

As part of the material exchange process, the valve is often used as a measuring or metering device.

Coates' International Ltd. has developed a spherical rotary valve for internal combustion engines which replaces the poppet valve system. The spherical rotary valve combustion engine possesses several significant advantages over the conventional poppet valve assembly, including significantly higher compression ratios.

[edit] Use in chromatography

The most common use of a rotary valve is for loading samples on columns used for liquid or gas chromatography. The valves used in these methods are usually 6-port, 2-position rotary valves.

[edit] See also

• Airlock
• Rotary feeder