Double Flange Butterfly Valve, ISO5211 butterfly valve  is type of resilient seated butterfly valves,with integral flanges cast on both ends.

same as all the other butterfly valves,it's a quarter-turn valve that rotates 90 degrees to open or close the media flow.  

Butterfly valve is also used as flow regulalting valve,if the disc does not rotate to a full quarter-turn, it means the valve is partially open,we can regulate the flow of fluids by various openning angle.

(CV/KV chart of resilient seated butterfly valve is available on request) 

NORTECH ISO5211 butterfly valve  is designed with long face to face,according to EN558-1 series 13. it can be used in many general applications such as in water distribution, water treatment, dams, power plants and in many other. The valve can be used as a stopper, a tap for discharging at the end of the pipeline, open/close and flow control. 

for large size pipeline,double flange butterfly valves are wided used.