Highly Challenging Manufacturing and Application of Aluminum Micro channel Flat Tubes in the Air Conditioning Field

Micro channel aluminum flat tubes, also known as parallel flow aluminum flat tubes, are thin-walled, porous flat-shaped materials made from refined aluminum rods. They undergo a process of thermal extrusion and surface zinc spraying for corrosion protection. Originally used in automotive air conditioning systems, they are now extensively applied in both residential and commercial air conditioning systems.

The technology involved in micro channel aluminum flat tubes is highly sophisticated, with significant manufacturing difficulties, especially given their small dimensions, with a width of only 12mm and a thickness of merely 1mm, requiring 12-16 pores. The challenges mainly lie in the following six aspects:

Extrusion Ratio: The cross-sectional area of micro channel aluminum tubes is only about 4px2, requiring an extrusion ratio of over 400 times, which is more than 8 times that of regular aluminum extrusion processes.

Air-Tightness: The quality standard is measured in PPM (parts per million), with a measurement standard of below 15PPM.

Dimensional Precision: The width deviation of micro channel aluminum tubes is ±0.03mm, and for high requirements, it needs to be improved to ±0.01～±0.02mm.

High-Quality Rod Material: Manufacturing micro channel aluminum flat tubes necessitates high-quality aluminum rods as raw materials.

Surface Zinc Spraying Technology: Micro channel aluminum tubes are susceptible to corrosion and may cause leakage. Hence, a thin layer of zinc must be sprayed on the outer surface to protect the tube walls from corrosion.

Online Inspection and Testing Technology: Due to the high complexity and numerous difficulties in the process, advanced online inspection and testing technology are required.