What are Butterfly Dampers?
Butterfly dampers are used to restrict the flow of materials in ducting systems where flow control and low leakage isolation are a priority. These dampers are especially useful in applications such as incinerators, balancing systems, control air systems, stack isolation, and scrubber systems. Butterfly dampers function best in round ducts, as their central pivot point allows them to maintain a tight, continuous seal around the damper’s circumference. Various types of seals can be used with butterfly dampers to offer better isolation and sealing potential. The best type of seal to use will also depend on the kind of gas being fed through the ductwork.
HOW DO BUTTERFLY DAMPERS WORK?
Butterfly dampers consist of a single round blade that pivots on a single, central hinge. The damper has a seal that the edge of the blade connects with all the way around the circumference of the pipe or duct. When the damper is fully closed, the edges of the blade press firmly against the seal to keep 90%-99% of materials isolated. The central hinge allows butterfly dampers to maintain even pressure on both sides of the damper blade, meaning that there is very little strain on the control mechanisms, and this makes them incredibly low maintenance. When maintenance is required to replace seals, the work can be done with fairly easy access. Because most of the butterfly damper’s mechanical workings are inside the duct, there is very little external space required for these dampers to be used.
- Sizes ranges from 6″ to 144″.
- Process temperature ranges to 2200° F.
- Round, square or rectangular configurations.
- Stainless steel or painted carbon steel construction.
- Shutoff options of 99% (tadpole seals), 97% (metal seat) & 90% (swingthru; control & balancing). Ball bearings and shaft packing glands standard.
- Actuation options of manual, electric, pneumatic with spring return and failsafe available. Open/Closed or modulating control.
- Standard designs to 1-PSI & 4000 FPM process air with higher available.