Aluminum foil can be divided into industrial aluminum foil and packaging aluminum foil. Industrial aluminum foil chemical composition is pure, the thickness of 0.005 ~ 0.2 mm, mainly for the electrical industry and the electronics industry, capacitors, insulation materials, moisture-proof materials. Packaging aluminum foil thickness is generally 0.007 ~ 0.1 mm, a flat foil, printing foil, color printing foil and Biaozhi aluminum foil and other products, mainly for food, tea, paper and other packaging materials. The minimum thickness of the aluminum foil produced by the belt production method is 0.0025 mm and the width is 1800 mm. The aluminum foil is rolled to roll without roll gap, and the roll is always in an elastic flattened state. The control of the thickness of the foil is achieved by adjusting the rolling force, the rolling speed and the control tension during rolling. In the rough rolling, the thickness of the foil is controlled by the rolling force. When the finish rolling, the thickness of the foil decreases with the increase of the rolling speed. The larger the tension is, the smaller the thickness is. In order to prevent the cutting, the tension selection is usually foil The conditional yield strength of the material is 0.2 to 0.4 of σ0.2. Low-speed rolling often in the lubricating oil by adding "thick oil" or "thin oil" to adjust the rolling thickness of aluminum foil. Lubricant and roll status have a very important impact on foil quality. Aluminum foil billet from cold rolled aluminum roll, generally by 340 ~ 480 ℃ pre-annealing, the thickness of 0.4 to 0.7 mm. Rolling deformation rate of about 50%, the total deformation rate of up to 95% or more. Finished thickness of less than 0.01 to 0.02 mm foil should be co-roll, double stack rolling.