| 摘要 |
PROBLEM TO BE SOLVED: To provide a heat exchanger which is equipped with a structure that achieves power saving and efficient temporary fixing with high accuracy when temporarily fixing flat pipes to each other by resistance welding.SOLUTION: An EGR cooler is equipped with a flat pipe 12, which has a midsection 31 with a rectangular cross section consisting of a short side 31a and a long side 31b and an opening 32 at one end and an opening 33 at the other end with rectangular cross sections consisting of short sides 32a and long sides 31b larger than the short side 31a, and a case, which stores seven flat pipes 12 in a lamination manner in a direction of short side. In this cooler, a side wall 32b is cut out at an edge of the long side 31b of at least either of the opening 32 at one end and an opening 33 at the other end of the flat pipe 12, whereby cut pieces 35, which are coupled partially within the same plane as the side wall 32b, are formed. |
