a butterfly valve controls the flow of material
“A BUTTERFLY VALVE is used to control the flow of material through a circular pipe or tube. They consist of a circular disc with its pivot axis at right angles to the direction material is flowing.”
Some of the applications that use butterfly valves are air, gas, steam and liquid. The body can be made up of different materials such as cast iron, ductile iron, aluminum, carbon steel, stainless steel and exotic metals.
“Depending on the application, additional valve features that may need to be considered. Some of these features include: the manner in which the stem and disc are attached, the way the stem and disc assembly mount inside the valve body, undercutting of disc, type of material used in stem bushings and packing, and availability of a ring seal between the seat and valve body.”
