The Swedish company Ortic, together with Bemo of Germany, has developed a new method of roll-forming steel sections in curved or varying shapes. The method, dubbed Monroe, utilises high-precision computer control and infinitely adjustable rollers. It permits the fabrication of sections with curved sides, conical shapes and variable profiles, which could previously be achieved only by using much more expensive methods. In time, the new method promises substantial cost reductions in the production of vehicle parts.

The Monroe method has been in practical use by the German company Bemo (which also took part in its development) for a couple of years. Bemo has used the variable roll-forming method on several very large and spectacular construction projects, in which custom-designed roofing and cladding sections were manufactured at high production rates by means of a mobile Monroe machine.

The success of the Monroe method is now opening the way to more efficient production in other industries as well. The automotive industry, for example, has used roll-forming for many years, but notwithstanding its economic advantages, the method has suffered from being limited to the manufacture of straight sections.

“Generally speaking, roll-forming is an efficient and economical way of making sections at high production rates,” says Lars Ingvarsson, CEO and owner of the Borlänge-based Ortic AB. “Its limitation has been that traditional roll-forming machines have fixed rollers .The difference with the Monroe machine is that we use rollers that are infinitely adjustable in various directions. This means we can now produce parts that would have been quite unthinkable for roll-forming in the past.”

Examples of vehicle parts that Lars Ingvarsson can envisage being fabricated by a Monroe roll-forming machine are the A and B pillars of vehicle bodies, which are often of curved shape. The Monroe method would also be suitable for many curved impact protection bars. The fact that these components are made of extra-high and ultra-high strength steel is not a problem, but is actually an advantage according to Ingvarsson.

“Roll-forming is a near-optimal method of working high-strength steels, and the automotive industry has a lot to gain from the Monroe method,” says Lars Ingvarsson.

Text: Roger Blomqvist News Magazine No 1 2005