Profile wall upsetting during the last transitions is one of the features of C-shaped profiles formation. It is typical for both sequential and combined pre-bending schemes. Profile wall upsetting allows getting the required radius zone and reducing profile springing back. At the same time, as a result of upsetting, there are significant effects on the outer part of profile flanging, which can lead to applied coating damaging.

 Finite element modelling was performed with LS-DYNA to analyze the effect of C-shaped profile upsetting. The FE model of the last transition and the billet before upsetting was built. Upsetting was carried out with the limiting value of 2.5S.

Modes allowing to get a high-quality section of parts with minimum internal radii and no defect in the coating were selected.