摘要 |
<p>In a plate heat exchanger, it is aimed to enhance strength, such as the pressure resistance and the internal pressure fatigue resistance, by increasing the joint area of a joint portion joined by brazing in a wave-patterned portion. Before a brazing process of the plate heat exchanger, a plurality of plates are stacked and pressure is applied thereto. By this pressure process, indentations of approximately "0.05 mm to 0.1 mm" are formed at contact points 9 of wave patterns in adjoining lower and upper plates. By brazing the plates after this pressure process, the joint area of the joint portion joined by brazing is increased. The increased joint area enhances the joint strength, and thus the strength of the plate heat exchanger such as the pressure resistance and the internal pressure fatigue resistance can be enhanced.</p> |