A method of preventing reannealing blocking of a buildup of aluminum foil rolls
By pre-treating and controlling the annealing process of aluminum foil rolls, the problems of interlayer adhesion and air bubbles during re-annealing of aluminum foil rolls were solved, achieving efficient conversion of unqualified aluminum foil rolls into qualified products, reducing scrap rate and production costs.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- SHENHUO NEW MATERIAL TECH CO LTD
- Filing Date
- 2026-02-06
- Publication Date
- 2026-06-05
AI Technical Summary
When aluminum foil rolls are re-annealed after being pressed for a long time, interlayer adhesion, bubbles, or even strip breakage are likely to occur. Existing technologies cannot effectively avoid this, resulting in high scrap rates and economic losses.
By pre-treating the aluminum foil rolls, including spray testing for wettability, loosening pre-treatment, and controlled annealing, the interlayer gap is increased, and a slow, medium-temperature annealing method is used to ensure the smooth escape of oil film decomposition gases and avoid adhesion and bubble phenomena.
This effectively avoids interlayer adhesion and air bubbles in aluminum foil rolls, reduces scrap rate, improves the pass rate and production efficiency of aluminum foil rolls, and reduces production costs.
Smart Images
Figure CN122147209A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of aluminum foil production technology, and more specifically to a method for preventing the adhesion of stockpiled aluminum foil rolls during re-annealing. Background Technology
[0002] Currently, aluminum foil rolls are usually packaged and stored after production. However, when aluminum foil rolls are stored and piled up for a long time, the lubricant on the surface of the aluminum foil roll is prone to aging, resulting in poor wettability of the aluminum foil roll surface and thus a decline in the performance of the aluminum foil roll. Therefore, aluminum foil rolls are usually subjected to a second high-temperature annealing treatment to improve their performance. This involves loading the aluminum foil rolls that need to be re-annealed into an annealing furnace and heating, holding, and cooling them according to a predetermined annealing process curve.
[0003] However, after re-annealing aluminum foil rolls that have been stored for a long time, interlayer adhesion, bubbles, and even strip breakage are likely to occur. For aluminum foil rolls that have been stored for a long time, the rolling oil remaining on the foil surface will oxidize and polymerize, forming a viscous product. When the aluminum foil roll is re-annealed, the heat in the annealing furnace will soften and migrate the aged oil film. Due to the tight winding between the layers of the aluminum foil roll, the oil and gas discharge channels are not smooth, and the viscous substance will re-solidify between the layers of the aluminum foil roll during the cooling process, acting as an adhesive. This will cause large-area, unpredictable random adhesion between the layers of the aluminum foil roll, and in severe cases, it may even cause the aluminum foil roll to unwind and break. At the same time, due to the small gaps between the layers of the aluminum foil roll and the tight winding, the gas volatilized from the decomposition of the oil film during the annealing process cannot be discharged smoothly and is trapped between the layers of the aluminum foil roll, thus forming bubble-like defects when the aluminum foil roll is cooled or used.
[0004] The occurrence of interlayer adhesion, bubbles, and even strip breaks in aluminum foil rolls is random and cannot be stably avoided by simply adjusting the annealing temperature and time. As a result, the re-annealing process for backlogged aluminum foil rolls becomes a high-risk process, with adhesion and strip breakage rates reaching over 80%, causing huge quality and economic losses. Summary of the Invention
[0005] This invention addresses the problem of interlayer adhesion, bubbles, and even strip breaks that easily occur when re-annealing stockpiled aluminum foil rolls in existing technologies. It provides a method to prevent adhesion during re-annealing of stockpiled aluminum foil rolls. This method pre-treats the stockpiled aluminum foil rolls that require re-annealing, effectively preventing interlayer adhesion, bubbles, and strip breaks. This allows for the stable and efficient conversion of substandard stockpiled aluminum foil rolls into qualified ones, reducing the scrap rate and production costs.
[0006] To achieve the above objectives, the technical solution of the present invention is: a method for preventing the re-annealing and adhesion of stacked aluminum foil rolls, comprising the following steps:
[0007] S1: Aluminum Foil Roll Condition Determination: The aluminum foil rolls are sprayed with a spray agent, and the rolls requiring re-annealing are identified based on the wettability of the foil surface. The wettability of the surface of the accumulating aluminum foil rolls is used to determine whether re-annealing is necessary.
[0008] S2: Aluminum Foil Roll Loosening Pre-treatment: The aluminum foil roll that needs to be re-annealed is placed on a slitting machine or rewinding machine for rewinding. Loosening the aluminum foil roll increases the physical gap between the layers, thus providing a smooth escape channel for the oil film decomposition gases generated during the annealing process and preventing air bubbles from forming between the layers.
[0009] The tension of the aluminum foil being wound is controlled between 50% and 80% of the normal tension of the slitting and winding aluminum foil. A tapered tension control mode is used for winding to gradually reduce the tension of the aluminum foil being wound. The speed of winding the aluminum foil is also controlled to run the winding of the aluminum foil at a low speed.
[0010] S3: Aluminum foil roll annealing treatment: The aluminum foil roll that has undergone loosening pretreatment is put into an annealing furnace for annealing treatment.
[0011] The temperature inside the annealing furnace is raised to between 170℃ and 220℃ using a stepped or uniform slow heating method, and the aluminum foil roll is then heat-insulated before being cooled. This second annealing process, combined with the increased gap between the aluminum foil layers, effectively removes the aged oil film from the foil surface, thus preventing adhesion between the foil layers.
[0012] Furthermore, in step S1, when spraying the aluminum foil roll surface, the aluminum foil roll surface is unfolded, and water mist is sprayed onto the aluminum foil roll surface using a spray bottle, while observing the wettability of the aluminum foil roll surface. The wettability of the compressed aluminum foil roll is tested by spraying water mist onto the surface of the compressed aluminum foil roll.
[0013] Furthermore, in step S1, if the water mist can spread evenly on the surface of the aluminum foil roll, it is determined that the aluminum foil roll does not need to undergo re-annealing; if the water mist cannot spread evenly on the surface of the aluminum foil roll, it is determined that the aluminum foil roll needs to undergo re-annealing, and proceeds to the next step of aluminum foil roll unwinding pretreatment. The wettability of the accumulated aluminum foil roll and whether re-annealing is necessary are determined by the phenomenon of water mist sprayed on the surface of the aluminum foil roll.
[0014] Furthermore, in step S2, when rewinding the aluminum foil roll, the rewinding environment must be kept clean, and the width of the aluminum foil roll must not be changed.
[0015] Furthermore, in step S2, the tension of the normally slit and wound aluminum foil is 42 N / mm², and a tapered control mode with decreasing tension from the core to the outer edge of the aluminum foil roll is adopted, with the aluminum foil being wound at a speed of 120 m / min. This results in an aluminum foil roll that is tight inside and loose outside, with uniformly increased physical gaps between layers.
[0016] Furthermore, in step S3, the temperature inside the annealing furnace is raised to between 170°C and 220°C at a heating rate of 10-20°C / h, and then the aluminum foil roll is kept at a temperature range of 170°C to 220°C. The holding time is determined according to the specifications of the aluminum foil roll (thickness * width * length in meters). The purpose is to ensure that the aged oil film on the surface of the aluminum foil roll is fully decomposed and volatilized.
[0017] Furthermore, in step S3, when cooling the aluminum foil roll, after the temperature of the aluminum foil roll drops below 200°C, it is then cooled to below 150°C at a cooling rate of less than 20°C / h, and subsequently cooled in the furnace. Using a slow cooling rate ensures that any residual oil or gas between the aluminum foil roll layers has sufficient time to escape smoothly from the increased gaps between the layers.
[0018] The beneficial effects of the present invention through the above technical solution are as follows:
[0019] This invention pre-treats the stockpiled aluminum foil rolls that require re-annealing, effectively preventing interlayer adhesion, bubbles, and even strip breaks. This allows for the stable and efficient conversion of substandard stockpiled aluminum foil rolls into qualified ones, reducing the scrap rate and production costs.
[0020] This invention uses a loosening pretreatment step to rewind aluminum foil rolls that need to be re-annealed, increasing the physical gap between the layers of the aluminum foil roll. This provides a smooth escape channel for the oil film decomposition gas generated during the annealing process, ensuring that the oil film decomposition gas can be discharged smoothly. From a physical structure perspective, this avoids the formation of "bubbles" due to the retention of oil film decomposition gas and excessive accumulation between the layers of the aluminum foil roll caused by thermal expansion, thus achieving the effect of avoiding the phenomenon of bubbles between the layers of the aluminum foil roll.
[0021] This invention, by increasing the gap between aluminum foil roll layers and using a "medium-temperature, slow-speed" annealing process, enables heat to be applied more evenly to the aluminum foil roll. This allows the aged oil film on the foil roll surface to fully and steadily decompose and volatilize at a relatively low temperature, avoiding the sintering or re-condensation of residues due to localized overheating or rapid cooling. This effectively removes the aged oil film from the aluminum foil roll surface, eliminating the source of viscous substances that cause aluminum foil roll layers to stick together, thus preventing adhesion or even strip breakage between aluminum foil roll layers. At the same time, the slow cooling rate during the aluminum foil roll annealing process ensures that residual oil and gas between the aluminum foil roll layers have sufficient time to escape smoothly from the increased gap between the aluminum foil roll layers.
[0022] This invention loosens the aluminum foil roll through a loosening pretreatment step, which also solves the problem of interlayer adhesion caused by physical stress. The loosening structure of the aluminum foil roll provides space for the free expansion of the aluminum foil when heated, alleviates the interlayer shear and compressive stress caused by uneven thermal expansion, and avoids the aluminum foil surface from undergoing microscopic plastic deformation under high pressure, which would aggravate adhesion. Attached Figure Description
[0023] Figure 1 This is a flowchart of a method for preventing the adhesion of stacked aluminum foil rolls during re-annealing according to the present invention. Detailed Implementation
[0024] The present invention will be further described below with reference to the accompanying drawings and specific embodiments:
[0025] like Figure 1 As shown, a method for preventing stacked aluminum foil rolls from sticking together during re-annealing includes the following steps:
[0026] S1: Aluminum foil roll condition determination: Spray the aluminum foil roll surface to identify aluminum foil rolls that need to be re-annealed based on the wettability of the aluminum foil roll surface. Detect the wettability of the surface of the accumulating aluminum foil roll to determine whether the accumulating aluminum foil roll needs to be re-annealed.
[0027] In step S1, when spraying the aluminum foil roll surface, the aluminum foil roll surface is unfolded, and water mist is sprayed onto the aluminum foil roll surface using a spray bottle. The wettability of the aluminum foil roll surface is observed. The wettability of the compressed aluminum foil roll is tested by spraying water mist onto the surface of the compressed aluminum foil roll. If the water mist can spread evenly on the aluminum foil roll surface, it is determined that the aluminum foil roll does not need to be re-annealed and is a qualified product that can be directly shipped out. If the water mist cannot spread evenly on the aluminum foil roll surface, it is determined that the aluminum foil roll needs to be re-annealed and proceeds to the next step of aluminum foil roll unwinding pretreatment.
[0028] S2: Aluminum foil roll loosening pretreatment: The aluminum foil roll that needs to be re-annealed is put onto the slitting machine or rewinding machine for rewinding. When rewinding the aluminum foil roll, the rewinding environment must be kept clean and the width of the aluminum foil roll must not be changed.
[0029] The tension of the wound aluminum foil is controlled between 50% and 80% of the normal slitting and winding tension, which is 42 N / mm². A tapered tension control mode is used for winding, in which the tension decreases from the core of the aluminum foil roll to the outer edge, so that the tension of the wound aluminum foil gradually decreases, resulting in an aluminum foil roll that is tight inside and loose outside with uniformly increased physical gaps between layers. The winding speed is also controlled, with the aluminum foil being wound at a low speed, specifically at 120 m / min, to ensure that the aluminum foil roll is wound flat.
[0030] The aluminum foil roll loosening pretreatment step loosens the aluminum foil roll that needs to be re-annealed, increasing the physical gap between the layers of the aluminum foil roll, fundamentally creating exhaust conditions, and providing a smooth escape channel for the oil film decomposition gas generated during the annealing process of the aluminum foil roll.
[0031] S3: Aluminum foil roll annealing treatment: The aluminum foil roll that has undergone loosening pretreatment is put into an annealing furnace for annealing treatment.
[0032] The temperature inside the annealing furnace is raised to between 170℃ and 220℃ using a stepped or uniform slow heating method, with a heating rate of 10-20℃ / h. The aluminum foil roll is then heat-insulated within the lower temperature range of 170℃ to 220℃. The holding time is determined based on the specifications of the aluminum foil roll (thickness * width * length in meters) to ensure the complete decomposition and volatilization of the aged oil film. The aluminum foil roll is then cooled. During cooling, after the temperature drops below 200℃, it is further cooled to below 150℃ at a rate of less than 20℃ / h, and then cooled with the furnace. This slow cooling rate allows sufficient time for residual oil and gas between the layers of the aluminum foil roll to escape smoothly from the increased interlayer gaps, thus preventing recondensation. After annealing, the aluminum foil roll is sprayed again to test its wettability. If it passes the test, it can be shipped out to the customer.
[0033] Specific Implementation Example 1: S1: Aluminum Foil Roll Status Determination: Spray the aluminum foil roll surface. Identify aluminum foil rolls that need to be re-annealed based on the wettability of the aluminum foil roll surface. Unfold the aluminum foil roll surface and spray water mist onto the aluminum foil roll surface using a spray bottle. If the water mist cannot spread evenly on the aluminum foil roll surface, then the aluminum foil roll is a wettability defective product. According to the record, it has been stored and accumulated for 92 days after its initial annealing.
[0034] S2: Aluminum foil roll loosening pretreatment: The accumulated aluminum foil roll is hoisted onto a slitting machine or rewinding machine for rewinding. The initial winding tension of the aluminum foil is set to 70% of the normal slitting and winding tension. A tapered control mode with a 30% decrease in tension from the core to the outer edge of the aluminum foil roll is adopted. Rewinding is performed at 40% of the normal speed to obtain loose aluminum foil roll.
[0035] S3: Aluminum foil roll annealing treatment: The loosely rolled aluminum foil obtained after loose pretreatment is loaded into an annealing furnace for annealing treatment. The temperature inside the annealing furnace is raised to 190℃ at a heating rate of 20℃ / h and held at 190℃ for 12 hours. Then, it is slowly cooled to below 150℃ at a cooling rate of 15℃ / h and then cooled in the furnace.
[0036] After the aluminum foil roll is annealed, there is no adhesion or air bubbles between the layers. The aluminum foil roll surface is then sprayed again. The wettability of the aluminum foil roll surface is tested and found to be qualified. Then the aluminum foil roll is shipped out and delivered to the customer for use.
[0037] Specific Implementation Example 2: S1: Aluminum Foil Roll Status Determination: Spray the aluminum foil roll surface. Identify aluminum foil rolls that need to be re-annealed based on the wettability of the aluminum foil roll surface. Unfold the aluminum foil roll surface and spray water mist onto the aluminum foil roll surface using a spray bottle. If the water mist cannot spread evenly on the aluminum foil roll surface, then the aluminum foil roll is a wettability defective product. According to the record, it has been stored and accumulated for 55 days after its initial annealing.
[0038] S2: Aluminum foil roll loosening pretreatment: The accumulated aluminum foil roll is hoisted onto a slitting machine or rewinding machine for rewinding. The initial winding tension of the aluminum foil is set to 55% of the normal slitting and winding tension. A tapered control mode with a 25% decrease in tension from the core to the outer edge of the aluminum foil roll is adopted. Rewinding is performed at 40% of the normal speed to obtain loose aluminum foil roll.
[0039] S3: Aluminum foil roll annealing treatment: The loosely rolled aluminum foil obtained after loose rolling pretreatment is loaded into the annealing furnace for annealing treatment. The temperature inside the annealing furnace is raised to 180℃ at a heating rate of 15℃ / h and held at 180℃ for 10 hours. Then, it is slowly cooled to below 150℃ at a cooling rate of 18℃ / h and then cooled in the furnace.
[0040] It can also achieve no adhesion or air bubbles between aluminum foil roll layers, and the wettability of the aluminum foil roll surface is well restored.
[0041] After the aluminum foil roll is annealed, there is no adhesion or air bubbles between the layers. The aluminum foil roll surface is then sprayed again. The wettability of the aluminum foil roll surface is tested and found to be qualified. Then the aluminum foil roll is shipped out and delivered to the customer for use.
[0042] The embodiments described above are merely preferred embodiments of the invention and are not intended to limit the scope of the invention. Therefore, any equivalent changes or modifications made to the technical solutions described in the claims of this invention should be included within the scope of the patent application of this invention.
Claims
1. A method of preventing re-annealing blocking of a buildup of aluminum foil rolls, characterized by, Includes the following steps: S1: Aluminum foil roll condition determination: Spray the foil surface of the aluminum foil roll and identify the aluminum foil rolls that need to be re-annealed based on the wettability of the foil surface. S2: Aluminum foil roll loosening pretreatment: The aluminum foil roll that needs to be re-annealed is put onto the slitting machine or rewinding machine for rewinding. The tension of the aluminum foil being wound is controlled between 50% and 80% of the normal slitting and winding tension. A tapered tension control mode is used for winding to gradually reduce the tension of the aluminum foil. The winding speed is also controlled to operate the aluminum foil winding at a low speed. S3: Aluminum foil roll annealing treatment: The aluminum foil roll that has undergone loosening pretreatment is put into the annealing furnace for annealing treatment; The temperature inside the annealing furnace is raised to between 170℃ and 220℃ using a stepped or uniform slow heating method, and the aluminum foil roll is then heat-insulated before being cooled.
2. The method for preventing the adhesion of stacked aluminum foil rolls during re-annealing according to claim 1, characterized in that, In step S1, when spraying the aluminum foil roll surface, the aluminum foil roll surface is unfolded, and water mist is sprayed onto the aluminum foil roll surface using a spray bottle, while observing the wetness of the aluminum foil roll surface.
3. The method for preventing the adhesion of stacked aluminum foil rolls during re-annealing according to claim 2, characterized in that, In step S1, if the water mist can spread evenly on the surface of the aluminum foil roll, it is determined that the aluminum foil roll does not need to be re-annealed; if the water mist cannot spread evenly on the surface of the aluminum foil roll, it is determined that the aluminum foil roll needs to be re-annealed, and the process proceeds to the next step of aluminum foil roll unwinding pretreatment.
4. The method for preventing the adhesion of stacked aluminum foil rolls during re-annealing according to claim 1, characterized in that, In step S2, when rewinding the aluminum foil roll, the rewinding environment must be kept clean, and the width of the aluminum foil roll must not be changed.
5. The method for preventing the adhesion of stacked aluminum foil rolls during re-annealing according to claim 4, characterized in that, In step S2, the tension of the normally cut and rolled aluminum foil is 42 N / mm², and a tapered control mode with decreasing tension from the core to the outer edge of the aluminum foil roll is adopted, and the aluminum foil is wound up at a speed of 120 m / min.
6. The method for preventing the adhesion of stacked aluminum foil rolls during re-annealing according to claim 1, characterized in that, In step S3, the temperature inside the annealing furnace is raised to between 170°C and 220°C at a heating rate of 10-20°C / h, and then the aluminum foil roll is kept at a temperature range of 170°C to 220°C. The holding time is determined according to the specifications (thickness * width * length in meters) of the aluminum foil roll.
7. The method for preventing the adhesion of stacked aluminum foil rolls during re-annealing according to claim 6, characterized in that, In step S3, when the aluminum foil roll is cooled, after the temperature of the aluminum foil roll drops below 200°C, it is then cooled to below 150°C at a cooling rate of less than 20°C / h, and then cooled in the furnace.