Friday, November 13, 2015

Eccentric Rotary Plug Control Valves

Eccentric plug valve
Eccentric plug valve
(courtesy of Neles/Metso)
A plug valve is typically a quarter-turn (90 deg rotation) on-off valve, while eccentric plug valves are often used for control applications. The plug may be cylindrical or tapered, and may be designed with a variety of port patterns. End connections are typically flanged, hub type, or butt weld.

Eccentric rotary plug valves are designed for liquid, gas, vapor and slurry control in general and demanding applications. They provide excellent control performance, and their capability to handle impure fluids makes them well suited in refining, petrochemical, chemical, natural gas, and fertilizer manufacturing applications.

The design of an eccentric plug valve uses a modified plug design (basically a plug cut in half) which is well suited for applications that require a higher seating force, but with minimal friction when cycling from open to closed position. Eccentric plug valves also provide improved shut off capabilities without significant increases in operating torque. This style valve is used for a wide range of flow control and isolation applications including clean water, dirty water, sewage, sludge, and slurries.