Introduction
The document provides technical specifications and details for the RSK Backdraught Damper, also known as the non-return damper, manufactured by LUCOMA AG. These dampers are designed to prevent unwanted air inflow and maintain consistent conditions in complex ducting networks.

Functionality
The backdraught dampers are equipped with special seals and bearings for the lamella axes, ensuring secure and reliable operation. They are suitable for both horizontal and vertical air flows and can be mounted in round ducts with flange connections or plug-in ends.

Construction
The housing is made from C-profiles in galvanized steel or aluminum, joined by screwed corner-pieces without welding. The dampers feature torsion-free, hollow-profile lamellas made of aluminum with replaceable seals, temperature-resistant up to 80°C. The damper axes are supported by slide-bearings made of oil-soaked sintered bronze.

Specifications
- Leak-rate: CEN 1751, Class 2
- Diameter of axes: 18 mm
- Connecting flanges: 25, 36, or 50 mm
- Housing depth: 165 mm

Options
- Interior insulation made of mineral wool
- Anodized or powder-painted damper
- Stainless steel construction (1.4301 or 1.4571)
- Ball bearing
- Isolated lamellae
- Limit switch
- Mesh grid
- 200° version
- Vertical airflow
- Combination with WSG

Dimensions and Pressure Loss
The document includes a graph illustrating pressure loss against inflow air-speed, indicating performance characteristics when the damper is completely open.

Conclusion
The RSK Backdraught Dampers are customizable to meet specific customer requirements in size and material, offering reliable performance in various ducting applications.