From the inner wall of the aluminum tube, since the refrigerant does not contain water, the inner wall of the copper aluminum connecting tube will not be corroded. The lower the heat transfer efficiency of the connecting pipeline between the indoor unit and the outdoor unit of the air conditioner, the more energy will be saved, or the better the insulation effect, the more power will be saved. Excellent bending performance, easy to install and move.

It is a kind of high-strength duralumin, which can be strengthened by heat treatment. It has medium plasticity in annealing, hard quenching and hot state, and good spot welding. When gas welding and argon arc welding are used, the aluminum tube tends to form intergranular cracks; The machinability of aluminum tube is good after quenching and cold work hardening, but it is not good in the annealing state.