Patent ID: 8793850

Claim:
A method for producing a tube with a folded progression of a bend formed as a transverse progression, comprising: making two miter cuts at a first position of a straight tube to be folded or for each fold of the transverse progression, resulting in two tube sections with miter cut surfaces extending along faces of cutting planes and a cutting wedge, the miter cuts are placed such that the cutting planes intersect at a point located inside the tube wall and at this point a bendable bar is left intact connecting the two tube sections, wherein the miter cuts are made such that the cutting wedge first remains in the tube for tube transport via not-severed or incompletely severed holding points that are spaced apart from the bendable bar; after tube transport, removing the cutting wedge from the two tube sections; bending the miter cut surfaces to each other at the miter cut surfaces; and connecting the miter cut surfaces to one another by welding around.