摘要 |
<p>A tube (200) and a heat exchanger with tubes, the tube (200) formed by rolling and brazing a metallic band-shaped material (A) recrystallized by annealing comprising a flat part (204) shaped by forming flat the material after bending; the heat exchanger comprising the tubes (200). A roll forming device (10) for roll-forming, comprising a plurality of rolls (11) continuously disposed with each other, wherein the transfer direction of the material between the plurality of rolls is set non-linear and, in the roll forming, the width of the material is sized and, after the material is folded up, the material is bent from the edge part of the material as a base point P.</p> |