Patent ID: 7134456
Filing Date: 2006-11-14
Classification: B21D

Abstract:
1. A pipe body having a rectangular cross section, comprising a metal plate having a pair of edges parallel to each other and a plurality of bending lines parallel to the pair of edges, wherein: the metal plate further comprises at least one malleable portion extending in a direction perpendicular to the bending lines of the metal plate; the metal plate is bent at the plurality of bending lines such that the metal plate includes a center bottom wall, first and second adjoining walls adjoining the center bottom wall, and two upper walls including the edges of the metal plate, respectively; the pair of edges in the two upper walls are brought into intimate contact with each other; and the at least one malleable portion is formed in at least one of the first and second adjoining walls; the metal plate further comprises at least one hole formed in at least one of the first and second adjoining walls, the at least one hole being adjacent to the at least one malleable portion; the at least one malleable portion is formed at at least one side of the at least one hole; and the at least one malleable portion has a longitudinal length which is greater than a diameter of the at least one hole.