Innovative Bending Strategies - Optimization of Bent Components to Suit Individual Load Cases Using Overbending and Underbending Strategies for the Free-Form Bending Process

The six independent axes available for free-form bending enable the production of complex three-dimensional bent tube and profile geometries. In industrial environments, only tangential bending strategies are currently used, which means that the bending head is always positioned parallel to the cross-section of the tube in the current bending section. Therefore, the individually controllable axes make it possible to apply other, non-tangential bending strategies. In so-called overbending, the bending head is rotated more in comparison to tangential bending. However, in order to ensure that the bending radius does not change compared to tangential bending, the translational deflection of the bending head must be reduced at the same time. In contrast, the bending head is rotated less during underbending and the translational deflection is increased. Overbending and underbending offer the possibility of improving the mechanical properties while maintaining the same bending geometry. These strategies allow the components to be optimized for individual load cases. As part of this work, a structural component was produced multiple times using free-form bending. Both conventional tangential bending strategies as well as innovative overbending and underbending strategies were applied. The mechanical stiffness of the bent components was then examined on a test bench. The influence of the bending strategy on the cross-sectional change in the bent area was investigated by using a tactile coordinate measuring machine. Furthermore, residual stress measurements were performed on the bent tubes, which allowed the different mechanical behavior of the tangentially bent, overbent and underbent tubes to be explained.     «

The six independent axes available for free-form bending enable the production of complex three-dimensional bent tube and profile geometries. In industrial environments, only tangential bending strategies are currently used, which means that the bending head is always positioned parallel to the cross-section of the tube in the current bending section. Therefore, the individually controllable axes make it possible to apply other, non-tangential bending strategies. In so-called overbending, the be...     »