| 摘要 |
PROBLEM TO BE SOLVED: To provide a heat exchange tube capable of reducing stress caused by heat, thus a pair of plates defining a flow channel, can be improved to have a longer service life in comparison with a conventional technology.SOLUTION: This invention relates to a heat exchanger including an integrally configured tube or a tube composed of two basin-shaped plates, in particular, an exhaust gas cooler. These tubes configure first and second fluid passages, and the fluid passages are disposed in adjacent to each other. The first fluid passage is formed in a state that at least one of end portions is opened so that the first fluid can flow in and out. The tube includes a stepped portion toward an inner side or an outer side at the end portion, thus an end face of the second fluid passage is closed. The stepped portion has an extended portion T larger than that in an edge region, in a longitudinal direction of the tube in the edge region of the tube.SELECTED DRAWING: Figure 1 |
