Abstract: A method and a roll-forming system for producing a metal profile are provided, wherein the wall thickness of the metal profile varies along its longitudinal axis. For this purpose, a sheet-metal strip with a thickness that varies along its length is used. Before welding together the profile or tube, which is manufactured through shaping into a closed profile or tube, this piece is sized to a desired outer diameter and in this way any existing ripples in the strip edges are made level, so that a simple, conventional straight welding of the profile or tube is possible.

Abstract: The invention relates to a method that can be applied to data processing programs that allow the user to repeatedly change data (10), especially programs that process electronic forms such as spreadsheet routines. The invention provides a method with which an erroneous overwriting of initially correct data (10) can be avoided. To this end, the method allows an automatic selection of critical data (12), that is data that shall not be overwritten, from the quantity of data (10) to be processed. Said critical data (12) are automatically protected from being unintentionally overwritten.