Development of a Profile Bending Process with Compressive Stress Superposition by Rolling

Funding: LeitmarktAgentur.NRW
Project: EFRE-0400139
Contact: Juri Martschin M.Sc.
Status: Completed

As part of this NRW patent validation, a process is developed that enables profile bending with compressive stress superposition.

When bending profiles made of high-strength steel, bending stresses of more than 1000 MPa may occur. High bending stresses cause process limitations such as the formation of wrinkles on the inner arc of the bent profile or the deformation of the profile cross section. As part of the NRW patent validation, a combined rolling and bending process is being developed for high-strength steels, which reduces the bending stresses by means of compressive stress superposition. To quantify the stress reduction, the resulting bending moment was determined by numerical simulations (see figure). In addition, an analytical model was developed for a simplified process design. A comparison of the applied bending moments taking into account the change in the cross section shows that a bending moment reduction of up to 80% is achieved. At present, the machine is under construction to test the process principle.

Bending moment reduction during bending with compressive stress superposition by rolling at const. bending radius RL and const. rolling 𝛥a = 𝛥b