Methods for making curved pieces from continuous metal elements are provided. Such methods include advancing a continuous metal element through a calendering station such that each length of the element assumes a pre-established curvature; stopping advancement of the element after a curved length thereof has passed through a wrap-bending station located downstream of the calendering station; wrap-bending the length of the element located at the station, while simultaneously conveying the curved portion to a stretch-bending station; stretch-bending the curved portion; resuming advancement of the element until the wrap-bent length is at a cutting station; and cutting the element in the wrap-bent length, thus producing the desired curved piece. Curved pieces produced by such methods are also provided.

Methods for making curved pieces from continuous metal elements are provided. Such methods include advancing a continuous metal element through a calendering station such that each length of the element assumes a pre-established curvature; stopping advancement of the element after a curved length thereof has passed through a wrap-bending station located downstream of the calendering station; wrap-bending the length of the element located at the station, while simultaneously conveying the curved portion to a stretch-bending station; stretch-bending the curved portion; resuming advancement of the element until the wrap-bent length is at a cutting station; and cutting the element in the wrap-bent length, thus producing the desired curved piece. Curved pieces produced by such methods are also provided.

A workpiece material is fed between rollers to bend the workpiece material while rolling, wherein the workpiece has a first thickness portion and a second thickness portion connected to each other with a setting angle of 90 degrees. The first thickness portion increases from an inner side toward an outer side, and a thickness on an outer peripheral side of the first thickness portion is M, and a thickness of a cross section of the second thickness portion is N. The workpiece material is rolled in such that at a completion of bending, a thickness of a cross section of a first thickness portion is m, an outer radius of the first thickness portion is R, an inner radius of the first thickness portion is r, and a thickness of a cross section of a second thickness portion is n, and M equals to m(R/r), and N equals to n(R/r).

A workpiece material is fed between rollers to bend the workpiece material while rolling, wherein the workpiece has a first thickness portion and a second thickness portion connected to each other with a setting angle of 90 degrees. The first thickness portion increases from an inner side toward an outer side, and a thickness on an outer peripheral side of the first thickness portion is M, and a thickness of a cross section of the second thickness portion is N. The workpiece material is rolled in such that at a completion of bending, a thickness of a cross section of a first thickness portion is m, an outer radius of the first thickness portion is R, an inner radius of the first thickness portion is r, and a thickness of a cross section of a second thickness portion is n, and M equals to m(R/r), and N equals to n(R/r).

Disclosed is a tube bending device which includes at least one bending roller mounted to be rotatably movable relative to a frame and at least one crease erasing member. This device is specific in that it includes a plate designed with: reception surfaces to receive, support and position the crease erasing member which is attached thereto, a unit for fixing to the frame, and guide surfaces pivotably connected for the roller.

A processing device processes a frame-shaped workpiece which extends in a prescribed extension direction, and includes, integrally, a plate-shaped web surface portion, a plate-shaped first flange portion that bends and extends from one end of the web surface portion, and a plate-shaped second flange portion which bends from the other end of the web surface portion and extends in the opposite direction to the first flange portion. The processing device includes a shaping device which conveys the workpiece in the extension direction, and an exit side pinch roll device provided further downstream, in the workpiece conveying flow direction, than the shaping device. The exit side pinch roll device includes a first roll which presses a central region of an upper surface side of the web surface portion, and a second roll which presses a central region of a lower surface side of the web surface portion.

A roll bender apparatus is disclosed for bending a work piece, the apparatus including a base, a bending roller rotatably disposed on the base, a first guide roller rotatably disposed on base. and a second guide roller rotatably disposed on the base. A first work piece guide assembly is movable about the first guide roller and a second work piece guide assembly movable about the second guide roller. The first and second work piece guide assemblies are oriented to receive the work piece, and the first and second work piece guide assemblies are configured to move about the first and second guide rollers respectively in response to the work piece being bent as the work piece is advanced between the bending roller and the first and second guide rollers.

Tube bending machines configured to bend a tube at a target bend location. The tube bending machines include a frame, a bending die assembly, and an alignment stem. The bending die assembly is supported on the frame and configured to bend the tube. The bending die assembly includes a bending die, a wheel frame, and a clamp. The wheel frame is coaxially mounted to the bending die. The clamp is configured to secure the tube to the wheel frame. The bending die, the wheel frame, and the clamp cooperate to define an actual bend location where the tube will be bent by the bending die assembly. The alignment system is operatively supported on the frame and configured to align the target bend location with the actual bend location.

To suppress occurrence of stress corrosion cracking in a weld due to tensile residual stress generated in a web or a middle rib in case of bend forming of an aluminum alloy extrusion having the weld on the web or/and the middle rib. In bend forming of the aluminum alloy extrusion, a peak position of tensile residual stress generated in the middle rib exists in a region other than the vicinity of the weld. Since the peak position is away from the weld by a distance, tensile residual stress in the weld is reduced, making it possible to suppress occurrence of stress corrosion cracking.

To suppress occurrence of stress corrosion cracking in a weld due to tensile residual stress generated in a web or a middle rib in case of bend forming of an aluminum alloy extrusion having the weld on the web or/and the middle rib. In bend forming of the aluminum alloy extrusion, a peak position of tensile residual stress generated in the middle rib exists in a region other than the vicinity of the weld. Since the peak position is away from the weld by a distance, tensile residual stress in the weld is reduced, making it possible to suppress occurrence of stress corrosion cracking.