Efficient Multi Louver Type Dampers
Multi louver type of dampers consist of several blades mounted parallel across a duct, with centrally provided shafts extending out through a frame and driven by a linkage system. Louver dampers are versatile, able in theory to handle any application in the power plant. Some of their advantages:
- Drive and linkage more readily accessible
- Control function simple with opposed blades.
- Thin metal blade construction gives quick response to thermal transients.
- Fast opening and closing.
- Low leakage to outside environment.
- Good modulation and control characteristics.
- Actuation power requirements are low.
- The drive for a louvered damper is simple, needing only 90° of motion. Louver dampers are best applied to balance or control flow. The normal leak path of 0.7% of duct area produces a three to five percent leak rate in average applications.
- A variety of options are available. Metallic spring seals, sealed (dust tight) blade ends, shear seals, and many materials are available.