First step is degreasing.
As far as we all know,
we will use some volatile oil for lubrication in the production process .
Normally at ordinary temperature, 90% of the volatile oil has been evaporated.
Next, we using 200℃~220℃ high temperature to further remove the rest 10% oil.
Second step is Spraying.
Mix purified water and brazing flux based on certain ratio
then use double row spray to ensure that each part can be spray in place
(if the spray pressure is low, the alarm system will ring.)
After spraying, air blade will remove excess flux and make the surface flux more uniform.
Third step is drying. After spraying, the core need to enter the drying furnace.
The temperature is controlled at 220℃~240℃ to avoid the oxide formed
on the surface of aluminum core due to overheating.