Abstract: A method for producing hollow profiles provided with different cross sections along the length thereof includes shaping the profiles in a die from one piece of cut metal sheet. According to said method, a convex or concave rounding produced on the edges of a longitudinal section results in material excess or material shortage in the transition regions, thereby preventing the material thinning or thickening in said transition regions during forming.

Abstract: The invention relates to a method for producing hollow profiles provided with different cross sections along the length thereof. Said profiles are shaped in a die from one piece of cut metal sheet (5, 6, 7). According to said invention, a convex or concave rounding produced on the edges of a longitudinal section (8a, 8b, 9a, 9b) results in material excess or material shortage in the transition regions (8, 9), thereby preventing the material thinning or thickening in said transition regions (8, 9) during forming.

Abstract: A bending device is described for thin-walled metal tubes (R) made of a straight tube guide (1), a core template (2), which adjoins the tube guide (1) and is pivotable in relation thereto, having a connection strip (3), and a mandrel, having a mandrel tip (4), which is flexible in the region of the core template (2), and a mandrel shaft (5), which adjoins the mandrel tip (4) and is rigidly connected thereto and is axially fixed (1) in the tube guide. In order to support the metal tube (R) to be bent over its entire surface on the inside in the active bending region during the bending procedure, the flexible mandrel tip (4), which comprises a radially incompressible solid cylinder made of elastomer, extends only over the starting section of the bending curve, where the bending procedure occurs.

Abstract: The invention relates to a method for manufacturing a sectionally reinforced member made of a tubular hollow profile (1) made of metal. For sectional reinforcement of the hollow profile (1), a sleeve (3) made of metal is slid onto the hollow profile (1) and on the entire area of the section to be reinforced is bonded with bonding agent (2), so that the wall of the tubular hollow section (1) and the sleeve (3) as a result of the bonding agent (2) form a bond. In order to facilitate sliding the sleeve (3) onto the hollow profile (1), the sleeve (3) is enlarged by heating, and/or the external dimensions of the hollow section (1) are reduced by cooling. Forming the hollow section (1) comprising the sleeve (3) into a member takes place prior to a finishing additional treatment step for the purpose of curing the bonding agent (2).

Abstract: The invention relates to a bending mandrel for a bending device and also to a bending method for pipes, more particularly pipes which have a large diameter-to-wall thickness ratio and are to be bent by a small radius, for example, of the order of magnitude of the pipe diameter. To this end use is made of a bending mandrel (5, 6) to whose rigid head (5) assembly (6) of springy sheet metal lamellae (6a, 6b) is attached to improve the bendability of the bending mandrel (5, 6) while maintaining a satisfactory supporting action, the lamellae (6a), with the exception of the outer lamellae (6b), having window-like cutaway portions (6c).

Abstract: A bending device is described for thin-walled metal tubes (R) made of a straight tube guide (1), a core template (2), which adjoins the tube guide (1) and is pivotable in relation thereto, having a connection strip (3), and a mandrel, having a mandrel tip (4), which is flexible in the region of the core template (2), and a mandrel shaft (5), which adjoins the mandrel tip (4) and is rigidly connected thereto and is axially fixed (1) in the tube guide. In order to support the metal tube (R) to be bent over its entire surface on the inside in the active bending region during the bending procedure, the flexible mandrel tip (4), which comprises a radially incompressible solid cylinder made of elastomer, extends only over the starting section of the bending curve, where the bending procedure occurs.

Abstract: The invention relates to a double-layered sheet metal with a first layer (5) of sheet metal comprising indented knobs (4.sub.I -4.sub.IV ; 4.sub.V -4.sub.VII ; 4.sub.VIII -4.sub.XIII), with several of these knobs forming the corner points of a geometrical segment (8.sub.I, 8.sub.II, 8.sub.III) of the first layer (5) of sheet metal, with a second layer (6) of sheet metal which is connected to the first layer (5) of sheet metal in the area of the tips (4a) of the knobs (4.sub.I -4.sub.IV ; 4.sub.V -4.sub.VII ; 4.sub.VIII -4.sub.XIII), and with a filling (7) made of filling material arranged in the void remaining between the layers (5, 6) of sheet metal. With such a double-layered sheet metal the danger of "total failure" in the case of a load exceeding elastically endured deformation is reduced in that the geometrical segment (8.sub.I, 8.sub.II, 8.sub.