摘要 |
<p>A damper assembly including a plurality of damper blades pivotable about parallel axes. Each blade includes a pair of parallel plates spaced apart by supporting members, the plates providing an open fluid passageway through the blade. When the damper blades are in the closed condition, the passageways form a single enclosed space into which pressurized sealing air may be introduced to render the damper gastight with respect to gases in the main duct. In the open condition the damper blades offer very little flow resistance by allowing conduit gases to flow through the passageways between the plates of the blades.</p> |