LFS was used on Aluminum Extruded Blade in Regular Model, and Brick is the only one to use the solution avoiding deformation of the blade shell which is inherent defect for vertical fastening solution.
Beside Classic Model, Brick recently launch Regular Model with Aluminum Extruded Blade to meet the requirement for more price competitive products and also for easy comparison with the similar fans in market.
Based on 14 years experiences on HVLS fan maintenance, we had witnessed many fracture accidents of Aluminum Extruded Blade, often we were requested to help for root cause analysis. The inspection results revealed that over 99% of the fracture occurred at the location of the root fastening bolts, the fastening bolts vertically penetrated the blade shell from top to bottom.
The “inherent defect” we mentioned above means the reliability of Vertical Fastening Solution is very easy be disturbed by machining precision of the blade shell or improper site installation, these factors directly affect the tightness of the bolts, once a little improper tightness occurs caused by a tiny clearance between, the bolt threads would cut the edge of the shell and resulted in enlarged holes and ultimately leading to fracture.
Birck innovatively develops LFS. Two 4mm-thick vertical ribs inside the blade cavity were used both as an integrated enhance structure and be a connection location with blade handle, an accommodating slot are opened on the upper surface of the blade shell. When the blade handle is fastened to the ribs, these slots compensate for any clearance, preventing blade deformation or indentations.
The challenge of LFS is that it requires drilling holes on side of the blade, which complicates the process and increases machining costs.
