The rolling speed directly affects the production efficiency of the aluminum foil packaging material. The higher the rolling speed, the higher the production efficiency. However, the aluminum foil rolling speed is affected by the following conditions.
1. Aluminum coil quality
Since the acceleration and deceleration process during aluminum foil rolling will cause the thickness of the aluminum coil to be out of tolerance, high-speed rolling must have corresponding large-diameter coils. To increase the rolling speed, the acceleration and deceleration time must be shortened or the automatic thickness adjustment function must be improved during acceleration and deceleration, otherwise out-of-tolerance waste products will increase.
2. Aluminum foil shape
During the aluminum foil rolling process, due to the effects of deformation heat and frictional heat, the temperature of the rolling deformation zone changes rapidly, resulting in changes in the roll shape, and the aluminum foil plate shape will also change with the change in roll shape.
When the rolling speed exceeds 800m/min, in order to obtain good plate quality, an automatic plate shape control system must be used to control the plate shape. Since the plate shape automatic control system uses automatic spraying, roll bending, and tilting, and more advanced rolling mills also use plate shape control technologies such as VC and DRS, the aluminum foil rolling speed and plate shape control level have been greatly improved, and the online processing of aluminum foil plate shape can be controlled below ±(9I-20I).
3. Surface brightness
When other process conditions are the same, the rolling speed is low, the oil film between the rolls is thin, the aluminum foil surface is closer to the roll surface, and the rolled aluminum foil has good brightness. When the surface brightness of aluminum foil is required to be high, the rolling speed of double-pass aluminum foil with a thickness of 0.006-0.007mm should not exceed 600m/min.
4. Finished product thickness
When the front and rear tension and rolling force remain unchanged, the thickness of the alu foil packaging decreases as the rolling speed increases.
5. Roll roughness
Under other conditions being equal, the rolling speed increases as the roughness of the work roll increases and decreases as the roughness decreases.
6. Rolling oil
Under other conditions being equal, the rolling speed decreases as the additive content in the rolling oil increases and the oil viscosity increases, and increases as the rolling oil temperature increases.
At present, the maximum rolling speed of aluminum foil rough and medium rolling mills has reached 2500m/min, but the speed will not increase infinitely. Because the rolling speed needs to be further increased, for example to 2800m/min, a series of problems such as vibration and control need to be overcome in mechanical design.
The maximum speed of most rough rolling mills is preferably 1800-2000m/min, the maximum speed of intermediate rolling mills can be 1500m/min, and the maximum speed of finishing mills should not exceed 1200m/min.