Why does aluminum coil bulge in the production of aluminum foil during high-speed rolling? Feiya Machinery makes a simple analysis on this issue.
1 Definition of bulging: bulging means that the surface of the rolled aluminum foil is partially or continuously raised along the rolling direction. The essence is that the aluminum foil is loose at this place, and the void ratio of the protrusion after winding is larger than that at the flat place. As the drumming becomes heavier, the drumming portion will bump, wrinkle or even crush.
2 Causes of drum kick: During the rolling of aluminum foil, a large amount of deformation heat and friction heat will be generated. The rolling deformation zone is always in a heated state. If the local temperature of the rolls in the deformation zone is too high, exceeding the maximum cooling capacity of the rolling cooling oil, so that the thermal expansion at this place becomes larger, the aluminum foil at the corresponding outlet becomes loose, such as in the process of aluminum foil winding If it is flattened, then the porosity after coiling is larger than that of the flattened area, and it will form a bulge after accumulation.
However, in actual production, the main causes of aluminum roll drums are as follows:
(1) The crown of the roller is large (2) The shape parameter is unreasonable, and the convexity of the blank is large
(3) Insufficient coolant injection pressure or blocked nozzle
(4) Unreasonable preparation of process lubricants
(5) The support roller has scratches
(6) The pressure of the flattening machine is large
(7) Large amount of pass reduction
