Butterfly valve

Butterfly valve is a quarter-turn rotational motion valve, that is used to stop, regulate, and start flow.

Butterfly valves are easy and fast to open. A 90° rotation of the handle provides a complete closure or opening of the valve. Large Butterfly valves are usually equipped with a so-called gearbox, where the handwheel by gears is connected to the stem. This simplifies the operation of the valve, but at the expense of speed.

Butterfly valves possess many advantages over gate, globe, plug, and ball valves, especially for large valve applications. Savings in weight, space, and cost are the most obvious advantages. The maintenance costs are usually low because there are a minimal number of moving parts and there are no pockets to trap fluids.

Advantages of Butterfly valves
▪️Compact design requires considerably less space, compared to other valves
▪️Light in weight
▪️Quick operation requires less time to open or close
▪️Available in very large sizes
▪️Low-pressure drop and high-pressure recovery

Disadvantages of Butterfly valves
▪️Throttling service is limited to low differential pressure
▪️Cavitation and choked flow are two potential concerns
▪️Disc movement is unguided and affected by flow turbulence