METHOD OF MANUFACTURING PIPE

To restrain occurrence of a clearance in a butting part of a pipe.SOLUTION: A pipe is formed by performing press molding on a U-shaped member having a U-shaped cross section. The U-shaped cross section has at least five curved parts. As the curved parts, a central curved part facing an opening between opposite ends of the U-shaped cross section is provided, and also right first and right second curved parts and left first and left second curved parts are provided. Each of at least the central curved part, the right first curved part and the left first curved part are smaller in radius of curvature of the part than a radius of curvature of a part corresponding to that part in a pipe cross section.SELECTED DRAWING: Figure 5 【課題】パイプの突合せ部に隙間が生じるのを抑制する。【解決手段】Ｕ字状断面を有するＵ字部材に対しプレス成形を行うことで、パイプが形成される。Ｕ字状断面は、少なくとも５つの湾曲部を有する。そして、湾曲部として、Ｕ字状断面の両端の間の開口に対面する中央湾曲部が設けられていると共に、右第１及び右第２湾曲部と、左第１及び左第２湾曲部とが設けられている。少なくとも中央湾曲部、右第１湾曲部、及び、左第１湾曲部の各部位は、当該部位の曲率半径が、パイプ断面における当該部位に相当する部位の曲率半径よりも小さい。【選択図】図５