After intensive research and various trials with soft roll tooling, we discovered much more. We managed to improve the situation by mixing in some proven DREISTERN rollforming tricks. However, the problem was only half- solved. We knew that in application the profile would be under great stress.

Eventually a profile form having two parallel welded seams proved to be stable enough. Commonly used welding methods, such as High Frequency, Spot or Resistance-Seam Welding were quickly excluded due to cross-section or welding speed. But could we avoid any surface imperfection after the profile was powder-coated? This question gave us the idea of laser welding. "Far too expensive!", was the first reaction, as two lasers would actually be necessary for both welding seams.

But we did not throw in our project engineer's towel so quickly. The final concept convinced our demanding customer: A pre-punching unit with a fast operating 200t press, 32 forming units, but with only one laser. An innovative beam guidance system handles both welding positions. The machine is now in operation at our customer's plant. The equipment capability study concerning all critical dimensions corresponds to a Cmk value of > 1.33. Which means that this roll forming system uses less than 75% of the challenging tight tolerance range, thus allowing the production manager to sleep soundly.