What is a butterfly valve?

A butterfly valve is a shut-off valve with a relatively simple concept. In closed position, the disc blocks the valve bore while in open position, the disc is turned to allow flow. A quarter turn takes the butterfly valve from fully open to fully closed position, or opposite, and thus the butterfly valve allows for quick opening and closure. The openings or closing time can also be regulated.

Where are butterfly valves used?

Butterfly valves can be used for a broad range of applications within water supply, wastewater treatment, fire protection and gas supply, in the pharma-, (petro) chemical and oil industries, in fuel handling systems, power generation, marine industry. Some of the advantages of this type of valve are the simple construction not taking up too much space, and the light weight and lower cost compared to other valve designs.

The butterfly valves can be operated by handles, gears or actuators according to any specific customer requirement.

Main design of butterfly valves

The butterfly valve can be centric or eccentric. On a centric (concentric) butterfly valve the stem is centered in the middle of the disc and the disc is centered in the bore. The eccentric butterfly valve has one or more offsets from the center depending if it is a  double or triple offset valve.