Safely design brazed aluminum heat exchangers to avoid thermal shock

Although brazed aluminum heat exchangers (BAHEs) are designed per American Society of Mechanical Engineers (ASME) Pressure Vessel Code Section 8, they are still very sensitive to temperature fluctuations. The corrugated aluminum plates are tightly brazed with one another, and they expand and contract together. This expansion/contraction between the corrugated plates or other parts of the BAHE can be disproportionate if the rate of temperature change is high, resulting in metal fatigue and possible cracks or leaks. The material will be slightly deformed due to these external forces. If these forces are lower than its yield strength, then the material will return to its original shape as the