Patent ID: 7971771

Claim:
A method for producing at least one tubular jacket, comprising: continuously forming a strip-shaped sheet material, transverse to a strip axis, into a closed jacket strip; welding of a longitudinal seam along the closed jacket strip; and cutting, the at least one tubular jacket from the closed and welded jacket strip, wherein a support edge arranged at one end of a piston-cylinder unit is provided on an inside of the continuously formed jacket strip for the cutting, essentially in the form of a closed circle and extending in a normal plane to the longitudinal axis of the jacket strip, which fits directly against the inside of the jacket strip and cooperates with at least one cutting tool to rotate around the strip axis, the at least one cutting tool being pivoted into the cutting position during the cutting operation along the support edge so that a cutting region rotates once around the longitudinal axis and, in the process, a tubular section of the jacket strip is cut off, and wherein during the cutting, the support edge and the at least one cutting tool are advanced along with the jacket strip and, following the cutting, the at least one cutting tool is moved to a non-contacting position relative to the support edge and together with the support edge, is moved counter to the movement of the jacket strip and back to the starting position occupied prior to the cutting operation wherein, before the welding, the strip-shaped sheet material is given a flat-pressed shape with two curving regions and, after welding, the flat-pressed jacket strip is expanded into the circular cross-section of the support edge by an expansion element arranged inside the jacket strip before the cutting.