Summary： In the production of double sheet foil, the rolling of aluminum foil is divided into three processes: rough rolling, intermediate rolling, and finishing rollin
In the production of double sheet foil, the rolling of aluminum foil is divided into three processes: rough rolling, intermediate rolling, and finishing rolling. From the perspective of the process, it can be divided roughly from the thickness of the rolling exit. The general division method is that the exit thickness is greater than Or equal to 0.05mm is rough rolling, the exit thickness is between 0.013 and 0.05 for intermediate rolling, and the single sheet finished product and double rolled product with exit thickness less than 0.013mm are finish rolling. Rough rolling is similar to the rolling characteristics of aluminum sheet and strip. The thickness control mainly depends on rolling force and post tension. The thickness of the rough rolling process is very small. Its rolling characteristics are completely different from the rolling of aluminum sheet and strip. It has aluminum foil rolling. The special characteristics are mainly as follows:
(1) Rolling of aluminum plate and strip. To reduce the thickness of the aluminum sheet and strip mainly depends on the rolling force. Therefore, the automatic thickness control method is based on the constant roll gap as the main AGC control method. Even if the rolling force changes, the roll gap can be adjusted at any time to maintain the roll gap to obtain a certain thickness. Consistent plate and strip. For aluminum foil rolling to medium precision rolling, the thickness of the aluminum foil is extremely thin. When rolling, increasing the rolling force makes it easier for the roller to deform elastically than the material being plastically deformed. It is not possible to elastically flatten the roller. Ignoring the fact that the rolling and flattening of the roll determines that the aluminum foil rolling does not have the same rolling force as the rolled sheet. The aluminum foil rolling is generally performed under constant pressure without roll seam rolling, and the thickness of the aluminum foil is adjusted. Mainly depends on the adjusted tension and rolling speed.
(2) Rolling. For extremely thin aluminum foil with a thickness of less than 0.012mm (the thickness is related to the diameter of the work roll), it is very difficult to use single sheet rolling because of the elastic flattening of the roll, so the double rolling method is adopted, that is, the A method in which two sheets of aluminum foil are lubricated and then rolled together (also referred to as stacking). Overlap can not only roll extremely thin aluminum foil that cannot be produced by single sheet rolling, but also reduce the number of strip breaks and improve labor productivity. Using this process can produce single-sided light aluminum foil with a thickness of 0.006mm to 0.03mm.
(3) Speed effect. In the process of aluminum foil rolling, the phenomenon that the thickness of the foil becomes thinner with the increase of the rolling system is called the speed effect. The explanation of the mechanism of the speed effect still needs to be further studied. The reasons for the speed effect are generally considered to have the following three aspects:
1) The friction state between the work roll and the rolling material changes. As the rolling speed increases, the amount of lubricating oil increases, thereby changing the lubrication state between the roll and the rolling material. The friction coefficient decreases, the oil film becomes thicker, and the thickness of the aluminum foil decreases accordingly.
2) Changes in the rolling mill itself. Rolling mills with cylindrical bearings, with the increase of the rolling speed, the roll neck will float in the bearing, so that the two interacting and loaded rolls will move towards each other.
3) The material is softened when it is deformed by rolling. The rolling speed of the high-speed aluminum foil rolling mill is very high. As the rolling speed increases, the temperature in the rolling deformation zone increases. According to calculations, the metal temperature in the deformation zone can rise to 200 ° C, which is equivalent to an intermediate recovery annealing. Process softening of rolled materials.