Roll forming of linear flow split profiles


Linear flow splitting is a massive forming process and is an alternative to conventional manufacturing processes concerning material properties and stiffness of cold rolled profiles. In the linear flow splitting process a flat sheet metal is moved translational through a tool system, which consists of supporting and splitting rolls. Through high hydrostatic compressive stresses the sheet metal material flows at the band edge and a bifurcation is created (Figure [1]).

Cold rolled profiles are often joined mechanically and have cut-outs, which have to be manufactured in an additional process.


Current researches at PtU concern further processing of linear flow split profiles, which enables a mechanical joining of several parts. For this purpose the linear flow split flanges have to be formed by a roll forming process to integral joining areas without an additional manufacturing process. Furthermore the high work hardened flanges are placed at the joining areas and offer durable and bearing bond of profiles (Figure [2]).

Picture: PtU Bildarchiv
[2] Bond of linear flow split profiles

Methodical approach

The linear flow split flanges are ultra-fine grained, which show a high strength by limited formabiliy. Therefore the profile flanges will be thermically (e.g. laser, induction) or mechanically (e.g. rolling) processed for a stable roll forming process to maintain the specific material properties.


The project “CRC 666 – Integral Sheet Metal Design with Higher Order Bifurcations” is funded by Deutsche Forschungsgemeinschaft (DFG)