Förfarande för rullformning av plåtämnen till profilbalkar och en anordning för genomförande av ett sådant förfarande

The invention concerns a method and an arrangement to control and monitor the profile form, in particular the thickness of the workpiece, of a profile beam (1), during the roll forming of sheet metal blanks (3) to profile beams (1) in a profile machine. A resulting profile beam (1) comprises a folded flange part (5) with a concave inner surface (7) and a convex outer surface (9). According to the method, a temperature difference (ΔΤ) is achieved in the material of the sheet metal blank (3) between the concave inner surface (7) and the convex outer surface (9) before the profiling operation or as a partial step during the profiling operation in the profile machine, through a region (13) that is intended to form the concave inner surface (7) being locally heated and a zone (15) that is influenced by heat being initiated at the said region (13).