In the production of double sheet foil, aluminum foil rolling is split into three processes: rough rolling, middle rolling and finishing rolling. From the purpose of view of the method, it may be roughly divided from the rolling exit thickness. the overall classification is that the exit thickness is bigger than or capable 0.05mm for rough rolling, and therefore the exit thickness between 0.013 and 0.05 for middle rolling. The finished sheet and double rolled products with outlet thickness but 0.013mm are finished rolling. The rolling characteristics of rough-rolled aluminum plate and strip are similar. The thickness control mainly depends on rolling force and post-tension. The thickness of rough-rolled processing rate is extremely small.
(1) aluminum plate and strip rolling. to create the aluminum strip thin mainly depends on the rolling force, that the automatic control mode of plate thickness relies on the control mode of constant roll gap because the main body of AGC. whether or not the rolling force changes, adjust the roll gap at any time to stay a specific value of the roll gap, the strip with the identical thickness is obtained. In rolling foil to finishing, thanks to the thickness of thin tin foil, rolling, increasing rolling force, make the rolls elastic deformation is less complicated than being rolled material to provide plastic deformation, the elastic flattening of roll cannot be ignored, roll play flattening determines the foil rolling, rolling force has been but like mill role, aluminum foil rolling is usually rolled without roll gap under constant pressure, and therefore the adjustment of tin foil thickness mainly depends on the adjusted tension and rolling speed.
(2) pack rolling. For the thickness of but 0.012mm(thickness size and therefore the diameter of the work roll) of tin foil, thanks to the elastic flattening of the roll, with one rolling method is incredibly difficult, therefore the use of double rolling method, that is, two pieces of foil with oil within the middle, then together rolling method (also referred to as rolling). Laminated rolling cannot only roll aluminum foil which may not be produced by single sheet rolling, but also reduce the amount of broken belt, improve labor productivity, using this process can produce 0.006mm ~ 0.03mm single light aluminum foil.
(3) Speed effect. During aluminum foil rolling, the phenomenon that the foil thickness decreases with the increase of the rolling system is termed velocity effect. the reason of the mechanism of speed effect remains to be further studied. the explanations for the speed effect are generally considered as follows:
1) The friction state between the work roll and therefore the rolled material changes. With the rise of the rolling speed, the number of grease is increased, so the lubrication state between the roll and therefore the rolled material changes. because the friction coefficient decreases, the oil film thickens and also the thickness of foil decreases.
2) Changes within the mill itself. In rolling mills with cylindrical bearings, because the rolling speed increases, the roller neck will float within the bearing, so the 2 rollers under interaction will move in a very direction near one another.
3) the processing softening of the fabric when it’s deformed by rolling. The rolling speed of high-speed foil mill is extremely high. With the rise of the rolling speed, the temperature of the rolling deformation zone increases. per calculation, the metal temperature within the deformation zone can rise to 200℃, which is reminiscent of an intermediate recovery annealing, thus causing the processing softening phenomenon of the rolling material.
Post time: Jan-04-2022