Pipe body, method of manufacturing pipe body, and image forming apparatus using the pipe body

摘要

A method of manufacturing a pipe body having a rectangular cross section, including preparing a metal plate having edges parallel to each other and bending lines parallel to the edges, forming malleable portions extending perpendicular to the bending lines, forming the metal plate into an intermediate product by bending at the bending lines such that the intermediate product includes a center bottom wall, adjoining walls, and two upper walls, applying external forces to the adjoining walls so as to expand and curve the center bottom wall outward, thereby bringing the edges in the upper walls into intimate contact, and applying external force to the curved center bottom wall so as to flatten the center bottom wall and maintain the edges in close contacted condition with a spring back force in the center bottom wall, wherein the malleable portions are formed in the adjoining walls.