Development of a Technology for Bending U-Profiles

Funding: BMWi/ZIM-ZF
Project: ZF4101104US6
Contact: Johannes Gebhard M. Sc.

Bending of metal profiles is currently restricted to high bending radii and, therefore, bent products are limited to spacious constructions.

The failures that limit the bending radius are wrinkling at the profile walls and cracks. In cooperation with the company FLORA GmbH & Co. KG, a technology has been developed to bend U-profiles with small bending radii. The used three-pointbending process is investigated analytically, numerically, and experimentally and has been developed to a modular roller-bending device with additional blankholder (see figure a). The blankholder supports the profile walls at the roller and can be used with constant holding force or with a fixed distance to the roller. Reliant on the setup of the blankholder, wrinkling can not entirely be prevented because the profile wall does not move uniformly in the gap between roller and holder (see figure b). Dependent on blankholder force or distance, width and height of the profile and bending radius, the process limits can be determined.

 

a) Bending device, b) Comparison of experimental and numerical results