Pre-coated aluminum foil used for punching various containers, commonly used alloy 8011, 3003, 3004, 1145, etc., thickness is 0.02-0.08mm. Oiling thickness is 150-400mg/m².
The use of aluminum foil as a semi-rigid container to hold food has been widely adopted at home and abroad. With the continuous development of the national economy and the continuous improvement of people’s living standards, people’s health awareness has been continuously strengthened, and people’s awareness of environmental protection has increased. Rigid container aluminum foil gradually replaced traditional foam and plastic food boxes.
Semi-rigid container foils are generally made of single zero foil, and in order to make containers of various shapes, the aluminum foil needs to be stamped and formed by a stamping method. However, without any treatment on the aluminum foil, in the stamping process, the aluminum foil will be scratched due to friction and the product quality will decrease. Therefore, the surface of the aluminum foil is coated with oil before stamping. The lubricating effect of the oil can protect the surface of the aluminum foil from being affected and improve the quality of the product.
The traditional oiling method is mainly the roller coating method. The roller coating method is the most primitive oiling method. Using the roller coating method to apply oil on the surface of the aluminum foil often causes uneven oil on the surface of the aluminum foil, which makes the production uneven during the stamping process. smooth. The lubrication effect is not obvious when the amount of oil is small, and the aluminum foil will be scratched; the amount of oil is too large, which will cause various problems such as adhesion of the aluminum foil and the stamping parts.
Inspired by the steel rolling industry’s anti-rust treatment on the surface of strip steel, people began to use electrostatic spraying to spray the surface of aluminum foil. Whether it is an imported electrostatic oiling machine or a domestic electrostatic oiling machine, the effect is obviously better than that of the traditional roller-coating oiling machine. It not only spreads the oil evenly, but also saves the oil, which has been praised by many customers. The oiling principle of the electrostatic oiling machine is shown in the figure.
Electrostatic oiling principle diagram
It can be seen that the changing form of the oil after flowing out from the cutting edge of the spray beam can be roughly divided into three stages: oil discharge, atomization, and oil application. When the oil is discharged from the cutting edge of the upper fuel injection beam 1, it is relatively thick and sparse negatively charged oil droplets. Under the action of the mutual repulsion of the same electric charges, the oil droplets will disperse into small particles at a certain distance from the cutting edge. The farther away from the cutting edge, the smaller the oil particles and the larger the quantity. The oil flow gradually becomes atomized. Such as fuel injection beam “fuel injection”. Negatively charged oil particles move quickly along the lines of power in the electric field toward the surface of the aluminum foil, and countless densely small oil particles are finally adsorbed on the surface of the moving aluminum foil to achieve classic oiling.