Numerical analysis of draw bending of load-adapted sheet metal profiles

In comparison to traditional roll forming processes, draw bending process represents a flexible and inexpensive production of open sheet metal profiles. Draw bending technologies allow the fabrication of load-adapted parts for applications in lightweight design. It enables the fabrication for predominantly bearing-like parts with adjustable cross sections along the longitudinal axis. This paper introduces the draw bending process with its functional principle and specifies the most important characteristics. It includes the key results of some research projects dealing with draw bending, which prove the applicability of this technique to produce load-adapted profiles. The fabrication of u-shaped profiles with various dimensions and adjusted cross sections as well as the fabrication of hat-shaped profiles with various widths of flange and adjusted longitudinal warping was investigated. The profiling is, in contrast to deep drawing processes, not bound to the form of the tools. The control of the draw bending process defines the contour of the profile during its production. Thereby an increased flexibility is achieved which is particularly useful for small series. Moreover numerical results are presented. The production of load adapted profiles and the buckling of the bottom area, as a result of a cross-sectional variation along the longitudinal axis are in the focus of the numerical and experimental investigations.