| 摘要 |
PROBLEM TO BE SOLVED: To provide a heat exchanger 1 capable of improving a corrosion resistant life. SOLUTION: The heat exchanger 1 comprises two heat transfer plates 4 for forming a tube 2, assembled by laminating and rolling a laminating and rolling part 4a of a second heat transfer plate 4B on the end of a first heat transfer plate 4A. The assembled two plates 4 are connected to the second heat transfer plate 4B at both surfaces of the first plate 4A. However, a first connecting part 8 provided at an inside with respect to a folding part of the second plate 4B is connected by using a Cu brazing material, and a second connecting part 9 provided at an outside is connected by using an Ni brazing material. According to this constitution, since the Cu brazing material used for the first connecting part 8 is not exposed with a combustion gas, even when the combustion gas is condensed to generate a condensed water, a corrosion of the Cu brazing material can be prevented. As a result, a sufficiently connecting strength can be maintained, and the corrosion resistant life of the heat exchanger can be improved. |
