During annealing, the tendency of aluminum foil to produce oil spots is related to factors such as process lubricating oil, annealing conditions and the degree of lubricating oil removal on the surface of aluminum foil after rolling. The single biggest influence is the type of lubricant.
Formation of oil spots: After the aluminum foil is rolled, a layer of lubricating oil remains on the surface. During annealing, the components with low volatile point in the formula oil volatilize first, while the components with high volatile point, such as mineral oil and additives with higher viscosity, not only It is not easy to volatilize, and some strong decomposition will occur, and there will be phenomena such as polymerization into chlorides. It can be produced under the conditions of aerobic production and can produce various complex reactions. These complex cracks, which polymerize into chlorination reactions, can eventually produce so-called oil spots on the foil surface.
|
Standard |
ASTM/DIN/GB/SUS |
|
Temper |
H32 H34 H36 H111 H112 H116 |
|
Thickness |
0.02mm ~ 350mm |
|
Width |
10mm ~ 2500mm |
The tendency to produce oil spots is also related to the smoke exhaust of the returned furnace and the atmosphere in the furnace: if the furnace has a ventilation system that is not equipped with a good exhaust steam, and the material is heated by hot air circulation, the lubricating oil will be removed from the inside of the reel. It is advantageous to remove quickly from the foil roll or out of the furnace. Therefore, the furnace should have a properly designed ventilation system. During operation, care must be taken to keep the chimney unobstructed and all the gates open.
In the atmosphere furnace for annealing with protective gas, since there is no chlorine gas, the heated product can be stabilized by repolymerization and continue to volatilize without residue. Therefore, for foils processed with high-viscosity lubricating oils, it is beneficial to prevent oil spots from occurring in this way.
Gnee is a diversified company, established in 2016 and headquartered in Tianjin, China. The main business scope of the company includes metal materials, daily necessities, and other fields. The company has been adhering to the corporate philosophy of integrity and innovation for development and has a professional R&D team and a high-quality sales and service team.
Hot Tags: aluminium foil raw material food grade, China aluminium foil raw material food grade manufacturers, suppliers, factory, Food Container Aluminium Foil, 3003 Aluminium Foil, Aluminum Foil for Food, Container Aluminium Foil
