Core structure of heat exchanger

摘要

In a core structure of a heat exchanger, tubes (3) and corrugated fins are alternately arranged between seat plates (2) arranged opposite to each other with a predetermined space interposed therebetween. End portions (3c) of the tubes (3) are inserted into tube holes (2b) formed respectively in each of the top and bottom seat plates (2) to be fixed. On the seat plates (2), there are provided connection portions (2c) having wall portions (2f) slanting from main body portions (2h) thereof toward the tubes (3). When a thickness of the tubes (3) is 0.13 mm to 0.23 mm, a slant angle θ of the wall portions (2f) of the connection portions (2c) is set to satisfy: slant angle θ (°) ≥ 25 × (thickness (mm) of sheet plate) + (-125 × (thickness (mm) of tube) + 25).