General Air visited a Broomfield fabricator of steel ventilation data center floor grids made of 1.5” by .80” mild steel straps. The fabricator was happy to show us their Fanuc 100i robot cell integrated with a Lincoln Powerwave 455M. While welding, it was clear by the sound of the MIG arc that the mode of weld transfer was a hybrid between short circuit and pulse, a combination that has no useful purpose in any application. Consequently, they needed to optimize their robotic welding procedure.
As expected, the hybrid transfer didn’t allow for optimal travel speeds and produced significant spatter that had to be removed. Shielding gas flow was also observed to be too high producing venturi effect porosity.
Moving as fast as possible from point A to B, without compromising weld integrity/quality, is one of the easiest ways to reduce labor costs, especially with robotic welding. Reducing spatter and porosity are others.
First, we had to find the arc length “sweet spot” that put us into a pure pulsed spray transfer. Then we incrementally increased wire feed speed and travel speed, maintaining arc balance and bead size, until we doubled travel speed from 20 to 40 IPM. We further reduced spatter 90% and, upon turning the shielding gas flow down to 45 CFH, eliminated porosity. The subject fabricator became a General Air customer because, in their words, “no distributor had ever delivered such powerful productivity solutions to our operation.”
Success Highlights: Over $21,933 Annual Savings
- Doubled travel speed from 20 to 40 IPM
- Cut Labor costs from $0.75 to $.035/per foot
- Reduced spatter by 75%
- Eliminated porosity