A manufacturing method for a pipe structure includes a pipe bending step for implementing for a plurality of times a bending process of bending a part of a straight pipe by wrapping the part around a peripheral surface of a rolling block to form a plurality of bend portions in intermediate locations along a longitudinal direction of the pipe. When a final bending process is implemented during the pipe bending step, a position of a rear end portion of the pipe is determined, and relative positions of the pipe and the rolling block in a predetermined y direction are controlled on the basis of the position of the rear end portion so that after the bending process, a y-direction position of the rear end portion is aligned with a y-direction position of the front end portion. According to this configuration, complicated operations such as cutting the respective end portions of the pipe after bending the pipe can be eliminated, and a pipe structure such as a meandering pipe body in which the positions of the respective end portions are aligned can be manufactured appropriately and with favorable productivity.

A manufacturing method for a pipe structure includes a pipe bending step for implementing for a plurality of times a bending process of bending a part of a straight pipe by wrapping the part around a peripheral surface of a rolling block to form a plurality of bend portions in intermediate locations along a longitudinal direction of the pipe. When a final bending process is implemented during the pipe bending step, a position of a rear end portion of the pipe is determined, and relative positions of the pipe and the rolling block in a predetermined y direction are controlled on the basis of the position of the rear end portion so that after the bending process, a y-direction position of the rear end portion is aligned with a y-direction position of the front end portion. According to this configuration, complicated operations such as cutting the respective end portions of the pipe after bending the pipe can be eliminated, and a pipe structure such as a meandering pipe body in which the positions of the respective end portions are aligned can be manufactured appropriately and with favorable productivity.

A method for warm forming an aluminum beam, such as an aluminum component for a vehicle, includes providing an extruded aluminum beam with a hollow cross-sectional shape. A portion of a forming die is heated to a desired temperature, so as to heat a portion of the aluminum beam in the die to a temperature below the artificial aging temperature of the aluminum beam. The heated aluminum beam is deformed to a desired shape with the die in a direction transverse to a length of the aluminum beam.

A round metal pipe 1 including a bend portion 10 is configured such that on an axial direction cross-section of the bend portion 10, an outer half portion 11b of a peripheral wall portion 11 of the bend portion 10 has an outwardly projecting, non-circular arc shape in which a central portion in a y direction, which is orthogonal to a bend radius direction x of the bend portion 10, forms an outermost peripheral portion 13, and a distance Lb from respective intermediate portions 15 between the outermost peripheral portion 13 and a pair of proximal end portions 14 of the outer half portion 11b to a pipe center O is shorter than a distance La from the outermost peripheral portion 13 to the pipe center O. Thus, advantages such as suppressing reductions in the sectional area and minimum inside width of the bend portion 10 and reducing flow path resistance can be obtained, and the round metal pipe 1 can be manufactured easily and appropriately.

A method for warm forming an aluminum beam, such as an aluminum component for a vehicle, includes providing an extruded aluminum beam with a hollow cross-sectional shape. A portion of a forming die is heated to a desired temperature, so as to heat a portion of the aluminum beam in the die to a temperature below the artificial aging temperature of the aluminum beam. The heated aluminum beam is deformed to a desired shape with the die in a direction transverse to a length of the aluminum beam.

A method of bending a tube arrangement including an inner tube disposed within an outer tube is performed using a bending die having a concave groove including a curved portion extending around a peripheral surface of the bending die, the curved portion of the concave groove having at least one ridge projecting therefrom. The tube arrangement is located within the concave groove and a force is applied to the tube arrangement in a direction toward the curved portion of the bending die to cause the tube arrangement to conform to the shape of the concave groove. The at least one ridge projecting from the concave groove causes the outer tube to deform such that an interior surface of the outer tube contacts an exterior surface of the inner tube, securing a position of the inner tube within the outer tube.

A method of bending a tube arrangement including an inner tube disposed within an outer tube is performed using a bending die having a concave groove including a curved portion extending around a peripheral surface of the bending die, the curved portion of the concave groove having at least one ridge projecting therefrom. The tube arrangement is located within the concave groove and a force is applied to the tube arrangement in a direction toward the curved portion of the bending die to cause the tube arrangement to conform to the shape of the concave groove. The at least one ridge projecting from the concave groove causes the outer tube to deform such that an interior surface of the outer tube contacts an exterior surface of the inner tube, securing a position of the inner tube within the outer tube.