A butterfly valve is a rotary valve (quarter turn valve) using a disc as the closure member. Butterfly valves can be either symmetric or eccentric (=offset), the latter referring to the stem being displaced from the center of the disc. Neles and Jamesbury butterfly valve offering covers concentric, double eccentric and triple eccentric designs. Thus, Jamesbury and Neles butterfly valves are a superb choice for most applications.

Neles and Jamesbury butterfly valves are available with wafer style (no flanges), lugged (single flange) and double-flanged body types. This along with comparably short face-to-face dimension makes them versatile and cost-efficient solutions for a variety of on/off and control applications. Extreme tightness performance makes the butterfly valves optimal for tight shut-off on/off applications and their inherent modified equal percentage flow characteristic makes them an excellent solution for a control valve.