Influence of selected certain force and energy parameters of modern levelling machines on the reliability of sheet metal straightening processes in roll forming and slitting lines.

This study evaluates the reliability of an 11-roll leveler when processing high-strength steels (HSLA, DP) instead of conventional structural grades (S235JR). Key indicators: leveling force, torque, drive power, and critical roll loads, were analyzed to define safe operational zones. For DP steels (Re = 650 MPa), maintaining structural integrity necessitates a 30% speed reduction and a 43% width reduction (from 1500 to 850 mm). Under these conditions, the machine operates at its technical limit, utilizing 99% of drive power and 98% of allowable force. A 23% load increase on the third roll highlights potential risks to the bearing system’s fatigue life. The findings provide practical guidelines for process engineers to optimize roll forming lines, minimize residual stresses, and prevent mechanical failure. The results demonstrate that processing advanced materials on existing machines is feasible but requires radical parameter adjustments to ensure the durability of the drive transmission and roller supports.