Method for manufacturing l-shaped square pipe, device for manufacturing l-shaped square pipe, and l-shaped square pipe

Abstract

Provided is a method for manufacturing an L-shaped square pipe that ensures adequate strength even without welding, a device for manufacturing the L-shaped square pipe, and the L-shaped square pipe. Provided is a method for manufacturing an L-shaped square pipe, comprising: a groove section forming step for forming a groove section by pressing one surface of a square steel pipe, along the shorter direction of the one surface, towards another surface positioned on the reverse side of the one surface; and a bending step for bending the square pipe so that the sides of the first surface sandwiching the groove section approach each other.

1 . A method for manufacturing an L-shaped square pipe, the method comprising:
 a groove section forming step for forming a groove section by pressing one surface of a square pipe along a shorter direction of the one surface to a side of an other surface located on a reverse side of the one surface; and   a bending step for bending the square pipe such that both sides of the one surface sandwiching the groove section approach each other.   
     
     
         2 . The method for manufacturing an L-shaped square pipe according to  claim 1 , wherein in
 the groove section forming step, the groove section is formed by pressing, to the one surface, a corner portion of a V-shaped portion in a pressing member having the V-shaped portion.   
     
     
         3 . The method for manufacturing an L-shaped square pipe according to  claim 2 , wherein
 an angle of the corner portion of the V-shaped portion corresponds to a bending angle of the square pipe.   
     
     
         4 . The method for manufacturing an L-shaped square pipe according to  claim 1 , the method further comprising,
 before the groove section forming step, a buckling line forming step for forming buckling lines by pressing two side surfaces between the one surface of the square pipe and the other surface inward along a longitudinal direction of the side surfaces.   
     
     
         5 . A device for manufacturing an L-shaped square pipe, the device comprising:
 a groove section forming device for forming a groove section by pressing one surface of a square pipe along a shorter direction of the one surface to a side of an other surface located on a reverse side of the one surface; and   a bending device for bending the square pipe such that both sides of the one surface sandwiching the groove section approach each other.   
     
     
         6 . An L-shaped square pipe, wherein a square pipe is bent through a groove section provided along a shorter direction of one surface thereof.