Dampers

BFD

The BFD is a rectangular backflow damper used in ventilation system where back flow or return air is to be prevented. Typically used when two fans in parallel (one running, one standby) to prevent backflow over idle fan.

The BFD is made in sizes from 100x100 to 1600x1600.

Image of BFD
Summary

Design

The BFD is a fully mechanical design, opening on air flow and closing on gravity using carefully calibrated counterweights.

It can be installed vertically for horizontal air flow or installed horizontal, either with upwards airflow or downwards airflow (should be used with caution.)

It is made in a balanced version for low pressure drop (suitable for low airspeeds) or an unbalanced version for higher airspeed (at lower cost).


Execution

Standard execution is in AISI316L stainless steel.

It can also be made with the frame in hot dip galvanized steel (blades in stainless steel 304/316) or aluminium (frame and blades).


Customizations

  • Can be made in with smaller depth (200 and 250mm) if space in limited
  • Regulation possibility (to allow damper to work as regulating damper as well)
  • Low or high temperature operation


Accessories

  • Sealing gaskets for low leakage (NORSOK)
  • Adapting plates for circular adaption
  • Lenkage arm on right side (seen from outlet)
  • Special flange
  • Thicker frame (e.g. if installed under fan.