Abstract: In recent years, aluminum has gained widespread attention as a substitute material for copper. Compared with copper tubes, the physical properties and wall thickness of aluminum tubes are inconsistent. The existing manufacturing process for copper fin-tube heat exchangers cannot be directly reused, and the manufacturing process needs to be optimized to meet the application requirements. Through theoretical analysis and experimental research comparison, analyzed the influence of different tube expansion processes on the heat transfer performance of aluminum round fin-tube heat exchangers. By optimizing the design of the expansion balls and adding an oiling process, experimental comparisons show that for the φ7 mm aluminum round tube finned heat exchanger, the heat exchange capacity is increased by approximately 2.2%; for the φ9.52 mm aluminum round tube finned heat exchanger, the heat exchange performance is enhanced by about 3.3%.

Key words: Aluminum pipe, Expanding ball, Lubrication, Heat exchanger