Dampers are utilized in multiple industries to regulate or constrict air flow. By analogy, dampers act as air valves. When open, they allow for air and when closed, prevent air flow. In the realm of isolation dampers (ID), the damper is used to prevent air or gas from entering a section of ductwork or machinery to retain it to a certain area.
Dampers can be square, rectangular or round. Square and rectangular dampers can be a one or two piece design or with multiple sections, as in a louvered design. Round dampers are often one piece, or a butterfly design, where the opening and closing is performed a central axis rod pivoting the round blade.
Gravity can be used to operate a damper, where the air flow itself opens and closes it. Gravity fed dampers are often seen in piping or ductwork, where the damper is intended to prevent back drafts, or air rushing through ductwork. In application where the machinery is large or where a more precise air flow regulation is necessary, dampers can be operated through an electric motor or hydraulic mechanism. Computerized components can be assembled to control the damper remotely.
In the residential field, most ductwork utilitizes dampers in the HVAC system. In the industrial field, the applications are limitless. In many industries, such as nuclear energy, the ID can be used to either expel noxious gases or prevent its escape into areas of human traffic. In other applications, such as biomanufacturing, medical equipment and electronic manufacturing, the ID can be used additionally for temperature control.
In industries where poisonous gases or extreme heat are present, the ID must be manufactured to precise standards. The components need to withstand extreme temperatures, caustic gas and corrosive conditions. Where hazardous gases are present, a minimal of leakage from the damper is vital. Leakage should be tested not only when first installed, but the product should be proven to allow minimal leaks after repeated use.
Most industries and military facilities have standards in which the components must be followed. ANSI standards for both manufacture and calibration of dampers should be certified by the damper manufacturer.
For military uses, the buyer should ensure military specifications MIL-I-45208A (quality program) and MIL-STD-45662A were followed. Welding is a necessary manufacturing step in nearly all dampers. The manufacturer should certify that all application standards of the American Welding Society and the ASTM were followed.