Considered as one of the oldest types of valves, plug valves are also called cock or stop cock valves. Plug valves are members of the rotary control valve family. Oftentimes, it belongs to the quarter-turn valve family.
As its name connotes, plug valves have a disc that looks like a plug. Plug valves are better as isolation valves although it is possible to act as a throttle valve.
Plug valves can be found in corrosive and neutral liquid and steam applications. Plug valves are common in gas and liquid fuel control applications. Because of its design, plug valves work well in low-pressure steam. It is also efficient in applications where low pressure and temperature apply.
Plug valves are also in applications where there is a need for multi-directional flow. While generally used for vapor and liquid operations, it can also handle slurries.
