Inflow of the production mannered null fluid of the heat exchanger, the tube and the

摘要

PROBLEM TO BE SOLVED: To prevent the collision of an abutting surface, formed at the end of a metallic material, against a projection, formed at the center of the metallic material, in a tube formed by bending the metallic material. ;SOLUTION: Upon shaping a metallic material, a projection 101 is formed at the center thereof and abutting parts 102 are formed by bending at the ends of the metallic material in the same direction as that of the projection 101. Then, the tip ends of the abutting parts 102 are slanted toward the projection 101 side and, thereafter, the metallic material is bent about bending parts 103 between the abutting parts 102 and the projection 101 to form a tube. In this case, relief parts 105 are bent forward the side of bending parts 103 in the final configuration whereby the abutting parts 102 are prevented effectively from colliding against the projection 101 by the relief parts 105 when the abutting parts 102 are maintained at the vicinity of the projection 101.;COPYRIGHT: (C)1998,JPO