The present invention provides a method for manufacturing a torsion beam, the method comprising: a planarization step, in which a protruding portion of an upper mold presses the opposite end portions in the width direction of the blank to be plastically deformed to be flat while the opposite end portions in the width direction of the blank are supported by a side cam to face each other; a welding and bonding step for bonding the planarized opposite end portions in the width direction of the blank via welding; and a quenching step for heating the welded and bonded blank within a range of 900 to 970? C. for a retaining time within a range of 1 to 20 minutes and for cooling down the blank in a treatment liquid including at least one of water and oil in a range of 20 to 90? C.

A method for manufacturing a double pipe includes: drawing a plate (1), which has a predetermined shape corresponding to the desired final shape of a curved outer pipe (4), into a curved, substantially U-shape in cross-section to produce a half pipe (2). Then, an inner pipe (3), which has a curved shape similar to the desired final curved shape of the outer pipe, is inserted into and positioned within the interior space of the half pipe. Subsequently, the inner pipe is welded to the half pipe at one longitudinal end thereof. Thereafter, longitudinally-extending edges of the half pipe are curled towards each other until they abut and a substantially circular cross-section is formed that surrounds the exterior of the inner pipe. The abutting longitudinally-extending edges (22) of the half pipe are then welded together to produce the curved outer pipe (4).

A method for manufacturing a double pipe includes: drawing a plate (1), which has a predetermined shape corresponding to the desired final shape of a curved outer pipe (4), into a curved, substantially U-shape in cross-section to produce a half pipe (2). Then, an inner pipe (3), which has a curved shape similar to the desired final curved shape of the outer pipe, is inserted into and positioned within the interior space of the half pipe. Subsequently, the inner pipe is welded to the half pipe at one longitudinal end thereof. Thereafter, longitudinally-extending edges of the half pipe are curled towards each other until they abut and a substantially circular cross-section is formed that surrounds the exterior of the inner pipe. The abutting longitudinally-extending edges (22) of the half pipe are then welded together to produce the curved outer pipe (4).

An article of furniture may include a component such as a frame, leg, or support. The component may be constructed from a strip of material and the strip of material may include a strip length, a strip width, and a strip thickness. The component may include a longitudinal welding joint that may be disposed between a first strip end or a first strip side and a second strip end or second strip side. A profile may be embossed into a surface of the strip of material and the component may be manufactured in a continuous inline roll forming process.

The disclosure relates to a method for producing a shaped sheet metal part from a billet by UO forming. First, a preform is created by the U-forming. Then, final forming to give a final form is carried out by the O-forming. The preform has in cross section a maximum width that is smaller than the maximum width of the final form produced after the O-forming.

A method for producing open-seam pipes from sheet metal panels, in particular thick sheet metal panels. A sheet metal panel, having bending edges on the long sides thereof, is fed to a pipe forming press, in which the sheet metal panel is formed, lying on a lower tool having of two supporting elements which are horizontally spaced apart from each other, by an upper tool, which can be raised and lowered, by application of a bending force, progressively into an open-seam pipe having bending edges on opposite long sides with a gap for later longitudinal seam welding. In order that the sheet metal panel can be easily, progressively formed or shaped from the start, at least the bending sections immediately adjacent on the bending edges of the sheet metal panel are each formed from the outside to the inside, deviating from a numerically ascending bending step sequence in the pilgering process.

A method of producing a polygonal closed cross-section structural component includes press-forming a metal sheet into a gutter-shaped pre-processed part with a curved form along its longitudinal direction having plural ridge lines corresponding to corner portions of the polygonal closed cross-section in a cross-sectional form developed by cutting the component at a position corresponding to the ridge line located at the innermost side in the radial direction to provide a flange portion extending along the ridge line at the resulting respective ends, and press-forming the pre-processed part to deform inwardly in the cross-sectional direction at a position of one or more of the plural ridge lines to butt the ridge lines located at the innermost side and the flange portions to each other.

A method of producing a polygonal closed cross-section structural component includes press-forming a metal sheet into a gutter-shaped pre-processed part with a curved form along its longitudinal direction having plural ridge lines corresponding to corner portions of the polygonal closed cross-section in a cross-sectional form developed by cutting the component at a position corresponding to the ridge line located at the innermost side in the radial direction to provide a flange portion extending along the ridge line at the resulting respective ends, and press-forming the pre-processed part to deform inwardly in the cross-sectional direction at a position of one or more of the plural ridge lines to butt the ridge lines located at the innermost side and the flange portions to each other.

A producing method to be disclosed is a producing method for producing a formed metal item that includes a tubular part with a slit. This producing method includes a step (i) of forming U-shaped part having a U-shaped cross section by deforming a metal plate, and a step (ii) of forming the tubular part with the slit by deforming the U-shaped part using a die assembly with a protruding part in such a manner that two end parts of the U-shaped part clamp the protruding part. In step (ii), a cross-section peripheral length LH of the tubular part is made shorter than a cross-section length LU of the U-shaped part.

A producing method to be disclosed is a producing method for producing a formed metal item that includes a tubular part with a slit. This producing method includes a step (i) of forming U-shaped part having a U-shaped cross section by deforming a metal plate, and a step (ii) of forming the tubular part with the slit by deforming the U-shaped part using a die assembly with a protruding part in such a manner that two end parts of the U-shaped part clamp the protruding part. In step (ii), a cross-section peripheral length LH of the tubular part is made shorter than a cross-section length LU of the U-shaped part.