Method for improving cylinder bottom staggered layer during annealing of aluminum foil finished product

Abstract

The invention discloses a method for improving cylinder bottom staggered layers during annealing of an aluminum foil finished product, and belongs to the technical field of aluminum foils. Winding a layer of kraft paper on the metal tube core for bottoming, winding the aluminum foil on the kraft paper, then standing for 1-2 days to eliminate internal stress, and then annealing; two ends of the kraft paper are provided with gaps and are connected through a plurality of thin adhesive tapes to form a cylinder matched with the metal tube core, and the kraft paper is adhered to the metal tube core through the thin adhesive tapes; the width of the gap is 1.0 to 2.0 mm; two sides of the kraft paper in the width direction are flush with corresponding sides of the aluminum foil, the gram weight is 70-80g / m < 2 >, and the smooth surface of the kraft paper is positioned on one side of the aluminum foil. The method has the following beneficial effects that (1) the possibility of layer staggering is reduced, and the probability of layer staggering is reduced from about 50% to about 10%; (2) during layer staggering, the length of the staggered layer and the starting end is reduced to 100-200 m from 300-500 m; and (3) during layer staggering, the probability of belt breakage is reduced from 40-50% to 20-30%.

Description

Technical Field

[0001] The invention belongs to the technical field of aluminum foil, and particularly relates to a method for improving the bottom staggering of an aluminum foil product during annealing. Background Art

[0002] Double zero foil is a foil with two zeros after the decimal point when its thickness is measured in mm, usually aluminum foil with a thickness of less than 0.007mm. Double zero aluminum foil is generally delivered in O state and needs to be annealed after rolling and slitting. The purpose of annealing double zero foil is usually to obtain a certain plasticity and to obtain a bright, clean and oil-free surface quality.

[0003] In the actual production process, for double zero aluminum coils with a width of ≥1200mm, during the annealing process, there are 1-2 layers of aluminum foil misaligned at the bottom of the aluminum coil tube at 5-15mm. When rewinding, the strip breaks at the misaligned part, and the aluminum foil is found to have wrinkles at the broken strip. When used at the customer's site, the strip often breaks at the misaligned part, causing the 5-15mm thick aluminum coil at the bottom of the tube to be scrapped, and the materials compounded with the aluminum foil to be scrapped, resulting in a lot of waste.

[0004] In the prior art, the staggered layer situation can be avoided by the following methods.

[0005] For example, the patent with application number CN202011409269.7 discloses a method for solving the wrinkles of aluminum foil annealing, which includes the following steps: Step 1, take an aluminum foil inner ring primer, the aluminum foil inner ring primer includes a sleeve and an aluminum foil waste layer rolled on the sleeve; Step 2, roll the aluminum foil to be annealed outside the aluminum foil waste layer to form an aluminum foil outer ring new material layer; Step 3, place the aluminum foil inner ring primer together with the aluminum foil outer ring new material layer in an annealing furnace to complete the annealing treatment of the aluminum foil outer ring new material layer. This patent has the following problems: waste aluminum foil is not easy to process and roll on a sleeve. It is suitable for 0.45mm aluminum foil, and the situation of broken belt is not considered. Summary of the invention

[0006] In order to solve the above problems, the embodiment of the present invention provides a method for improving the bottom misalignment of aluminum foil during annealing, which can reduce the misalignment and belt breakage. The technical solution is as follows: The embodiment of the present invention provides a method for improving the bottom misalignment of an aluminum foil finished product during annealing. During annealing, the aluminum foil is wound on a metal tube core 1 and then sent into an annealing furnace for annealing; a layer of kraft paper 2 is wound on the metal tube core 1 as a base, and the aluminum foil is then wound on the kraft paper 2, and then left to stand for 1-2 days to eliminate internal stress, and then annealing is performed; both ends of the kraft paper 2 have gaps 3 and are connected by multiple pieces of thin tapes 4 to form a cylindrical shape that matches the metal tube core 1, and at the same time, the thin tapes 4 adhere the kraft paper 2 to the metal tube core 1; the width of the gap 3 is 1.0-2.0 mm; the two sides of the kraft paper 2 on the width are flush with the corresponding sides of the aluminum foil, and its gram weight is 70-80 g / m 2 , its smooth surface is located on the aluminum foil side, and its rough surface is located on the metal tube core 1 side.

[0007] Specifically, the width of the aluminum foil in the embodiment of the present invention is greater than or equal to 1200 mm, the thickness is less than 0.007 mm, and the material thereof is 8079.

[0008] Specifically, when the aluminum foil in the embodiment of the present invention is initially rolled up, alcohol is sprayed on the outer surface of the kraft paper 2, and the starting end of the aluminum foil adheres to the kraft paper 2 through the alcohol.

[0009] Specifically, the metal tube core 1 in the embodiment of the present invention is a stainless steel tube core.

[0010] Specifically, after the aluminum foil is wound, the metal tube core 1 and the aluminum foil thereon are placed in a material frame, left to stand in the material frame for 1-2 days to eliminate internal stress, and then the material frame is sent to an annealing furnace for annealing.

[0011] Specifically, the kraft paper 2 is fixed on the metal tube core 1 before the aluminum foil is slitting, and the kraft paper 2 can be arranged on the slitting equipment.

[0012] The technical solution provided by the embodiment of the present invention has the following beneficial effects: (1) Reduce the possibility of misalignment, reducing the probability of misalignment from about 50% to about 10%; (2) When staggered, reduce the length between the staggered layer and the starting end; in the prior art, the distance between the staggered layer and the metal tube core is 5-15 mm, and the length of the waste aluminum foil is 300-500 m; this patent is 100-200 m; (3) When the layers are staggered, the probability of belt breakage is reduced. In the prior art, the probability of belt breakage after staggering is 40-50%; in this patent, it is 20-30%; (4) The slitting, winding and bonding of kraft paper are simple and can be achieved using common equipment with simple operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is a schematic diagram of the staggered layer in the prior art. Figure 1 ; Figure 2 This is a schematic diagram of the staggered layer in the prior art. Figure 2 ; Figure 3 It is a schematic diagram of a broken belt in the prior art; Figure 4 This is a schematic diagram of the aluminum foil unfolding at the staggered layer; Figure 5 It is a schematic diagram of the structure in which the aluminum foil of the present invention is wound on a metal tube core; Figure 6 yes Figure 5 A partial enlarged view of .

[0014] In the figure: 1 metal tube core, 2 kraft paper, 3 gap, 4 thin tape. DETAILED DESCRIPTION

[0015] In order to make the objectives, technical solutions and advantages of the present invention more clear, the present invention will be further described in detail below with reference to the accompanying drawings.

[0016] Example 1 Example 1 provides a method for improving the bottom staggering of aluminum foil during annealing. The annealing process is as follows: S101: Before slitting, apply a primer on the metal tube core 1. The two ends of the kraft paper 2 have a gap 3 and are connected by multiple thin tapes 4 to form a cylindrical shape that matches (tightly matches) the metal tube core 1. At the same time, the thin tapes 4 adhere the kraft paper 2 to the metal tube core 1. Among them, multiple thin tapes 4 are arranged side by side in the axial direction of the metal tube core 1, and the thin tapes 4 are perpendicular to the metal tube core 1 and the inner side thereof is an adhesive surface. Specifically, a piece of thin tape 4 is arranged at a distance of 200-300mm. The thickness of the thin tape 4 is 10um.

[0017] The two ends of the adhesive tape 4 are respectively bonded to the two ends of the kraft paper 1 , and the middle part thereof is recessed downward, passes through the gap 2 and is bonded to the metal tube core 1 .

[0018] The width of the gap 2 is 2 mm. The two sides of the kraft paper 2 are flush with the corresponding sides of the aluminum foil, and its gram weight is 75 g / m 2 The smooth surface is located on the side of the aluminum foil (specifically the outer side), and the rough surface is located on the side of the metal tube core 1 (specifically the inner side).

[0019] S102: During the slitting process, the aluminum foil is wound around the surface of the kraft paper 2 to form an aluminum foil roll with a length of 1200 m. When the aluminum foil is initially wound, alcohol is sprayed on the outer surface of the kraft paper 2, and the starting end of the aluminum foil adheres to the kraft paper 2 through the alcohol.

[0020] S103: Put the metal tube core 1 and the aluminum foil thereon into a material frame, and leave them in the material frame for 1-2 days to eliminate internal stress.

[0021] S104: sending the material frame into an annealing furnace for annealing, and the annealing conditions are the same as those in the prior art.

[0022] The annealing results of this patent are: the number of annealed rolls is 126 rolls, the number of staggered rolls is 11 rolls, the number of broken rolls is 2 rolls, and the average length of waste aluminum foil is 113m.

[0023] If no primer is performed: the number of annealed rolls is 126 rolls, the number of staggered rolls is 62 rolls, the number of broken rolls is 21 rolls, and the average length of waste aluminum foil is 471m.

[0024] Comparative Example 1 The gap is 4 mm, and the rest is consistent with Example 1.

[0025] Specifications of aluminum foil 1: length 12000m, width 1320mm; Specifications of aluminum foil 2: length 12000m, width 1520mm; Specifications of aluminum foil 3: length 12000m, width 1640mm.

[0026] The annealing furnace annealed 100 coils each time (the maximum number of coils annealed was 126), half of which were Comparative Example 1 and the other half were Example 1. The results are shown in Table 1: Table 1

[0027] As can be seen from Table 1, if the gap is too large, the length of the waste aluminum foil will increase significantly, the probability of staggered rolls is about 16% (11.3% in this patent), and the possibility of broken tape is 25% (slightly higher than this patent, which is 23.5% in this patent).

[0028] Comparative Example 2 The gap is 0 mm, and the rest is consistent with Example 1.

[0029] Specifications of aluminum foil 1: length 12000m, width 1320mm; Specifications of aluminum foil 2: length 12000m, width 1520mm; Specifications of aluminum foil 3: length 12000m, width 1640mm.

[0030] The annealing furnace annealed 100 coils each time (the maximum number of coils annealed was 126), half of which were Comparative Example 2 and the other half were Example 1. The results are shown in Table 2: Table 2

[0031] It can be seen from Table 2 that without setting the gap, the number of staggered rolls increases significantly (34%, 10.7% in this patent), and the probability of belt breakage increases slightly (35.3%, 25% in this patent).

[0032] Comparative Example 3 The gram weights of kraft paper are 40, 50, 60, 72, 75, 90 and 100 g / m 2 , the rest is consistent with Example 1.

[0033] Specifications of aluminum foil 1: length 12000m, width 1320mm; Specifications of aluminum foil 2: length 12000m, width 1520mm; Specifications of aluminum foil 3: length 12000m, width 1640mm.

[0034] The annealing furnace annealed 100 coils each time (the maximum number of coils annealed was 126), half of which were Comparative Example 3 and the other half were Example 1. The results are shown in Table 3: Table 3

[0035] As can be seen from Table 3, the gram weight is 70-80g / m 2 The product quality is stable, the probability of staggered layers is low, the length of waste aluminum foil under staggered layers is short, and the probability of broken tape under staggered layers is low, which are the more preferred conditions.

[0036] Comparative Example 4 It is not placed to eliminate internal stress, and the rest is consistent with Example 1.

[0037] Specifications of aluminum foil: length 12000m, width 1520mm; The annealing furnace anneals 100 coils each time (the maximum number of coils annealed is 126), half of which are comparative example 4 and the other half are example 1. The results are shown in Table 4: Table 4

[0038] It can be seen from Table 4 that if the material is not left to stand to eliminate stress, the method of the present invention will be greatly reduced.

[0039] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A method for improving the bottom staggering of aluminum foil finished products during annealing. During annealing, the aluminum foil is wound on a metal tube core (1) and then sent into an annealing furnace for annealing; the method is characterized in that: A layer of kraft paper (2) is wound around the metal tube core (1) as a base, and aluminum foil is then wound around the kraft paper (2), and then left to stand for 1-2 days to eliminate internal stress, and then annealed; the two ends of the kraft paper (2) have gaps (3) and are connected by multiple thin tapes (4) to form a cylindrical shape that matches the metal tube core (1). At the same time, the thin tapes (4) adhere the kraft paper (2) to the metal tube core (1); the width of the gap (3) is 1.0-2.0 mm; the two sides of the kraft paper (2) on the width are flush with the corresponding sides of the aluminum foil, and its gram weight is 70-80 g / m 2 The smooth surface is located on the aluminum foil side, and the rough surface is located on the metal tube core (1) side.

2. The method for improving the bottom staggering of aluminum foil during annealing according to claim 1 is characterized in that: The width of the aluminum foil is greater than or equal to 1200 mm, the thickness is less than 0.007 mm, and the material thereof is 8079.

3. The method for improving the bottom staggering of aluminum foil during annealing according to claim 1, characterized in that: When the aluminum foil is initially rolled up, alcohol is sprayed on the outer surface of the kraft paper (2), and the starting end of the aluminum foil adheres to the kraft paper (2) through the alcohol.

4. The method for improving the bottom staggering of aluminum foil during annealing of finished product according to claim 1, characterized in that: The metal tube core (1) is a stainless steel tube core.

5. The method for improving the bottom staggering of aluminum foil during annealing according to claim 1, characterized in that: After the aluminum foil is wound, the metal tube core (1) and the aluminum foil thereon are placed in a material frame and left to stand in the material frame for 1-2 days to eliminate internal stress, and then the material frame is sent to an annealing furnace for annealing.

6. The method for improving the bottom staggering of aluminum foil during annealing of finished product according to claim 1, characterized in that: The kraft paper (2) is fixed on the metal tube core (1) before the aluminum foil is cut.

Images