Method for controlling temperature uniformity of inner ring and outer ring of aluminum plate strip coiled material
By adjusting the rolling speed of the strip head and tail during the hot-rolled aluminum strip processing, and using the gradient temperature control module, the problem of temperature difference between the inner and outer rings is solved, temperature uniformity control is achieved, and tissue performance is improved.
Patent Information
- Application Number
- CN202411946019.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-27
- Publication Date
- 2025-02-11
AI Technical Summary
During the processing of hot-rolled aluminum strips, the temperature difference between the inner and outer rings is large, resulting in uneven temperature during the annealing process, affecting the uniformity and performance of the material structure.
By adjusting the rolling speed of the strip head and tail during the rolling process, the gradient temperature control module is used to compensate for the difference between the inner and outer rings and ambient temperature, and the temperature uniformity control is achieved.
It effectively improves the structural performance after rolling and annealing, ensures the uniformity of the temperature of the inner and outer rings, extends the recrystallization time, and improves the fine uniformity of the material texture.
Smart Images
Figure CN119406936A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of aluminum alloy processing, and in particular to a method for controlling the temperature uniformity of inner and outer rings of an aluminum plate and strip coil. Background Art
[0002] During the hot rolling process of aluminum strip, the rolled piece is affected by factors such as the pass processing rate, rolling speed, ambient temperature, lubrication and cooling, and different temperature fields will be generated in different parts of the hot rolled aluminum strip along the coil diameter direction. Affected by heat conduction, the temperature difference between the inner and outer rings of the strip and the ambient temperature is large, and the temperature difference between the inner and outer rings is more obvious.
[0003] The hot rolling process involves hot working and corresponding annealing.
[0004] Hot working is the plastic forming process of aluminum and aluminum alloy ingots above the recrystallization temperature. During hot working, comprehensive dynamic recrystallization occurs inside the aluminum material. In each pass, the hardening and softening processes occur simultaneously. The rolled fibers extended during the plastic deformation process are crushed by rolling. After recrystallization, the material structure becomes relatively uniform and fine equiaxed grains. However, the uniformity and fineness of the equiaxed grains depends on the temperature and holding time of static recrystallization.
[0005] After the thermal deformation is completed, the static recrystallization of the annealing process quickly replaces the dynamic recrystallization process. Therefore, maintaining the temperature of the inner and outer rings of the strip is a sufficient condition for the static recrystallization of the annealing process and is the key control factor for maintaining uniform and fine equiaxed grains in the inner and outer rings of the strip. Therefore, how to compensate for the heat dissipation effect of the outer ring is the difficulty of this technical research. Summary of the invention
[0006] The present invention proposes a method for controlling the temperature uniformity of inner and outer rings of an aluminum plate and strip coil. The method can change the uneven temperature state of the inner and outer rings of the strip through gradient temperature input adjustment according to the final rolling temperature requirement of the hot-rolled strip, achieve the uniformity of the temperature of the inner and outer rings during the annealing process after the coil finish rolling, and improve the organizational properties after rolling annealing.
[0007] The present invention adopts the following technical solutions.
[0008] A method for controlling the temperature uniformity of inner and outer rings of an aluminum plate and strip coil. The coil is formed by rolling a strip rolled from an aluminum material. The head of the strip is located at the inner ring of the coil, and the tail of the strip is located at the outer ring of the coil. During the rolling process, the heat dissipation time at the inner ring of the coil is longer than that of the ring layer in the middle section of the coil, and the temperature difference between the temperature at the outer ring of the coil and the ambient temperature is greater than that of the ring layer in the middle section of the coil. The control method increases the temperature of the inner ring of the coil by increasing the rolling speed of the head of the strip during the rolling process, and increases the temperature of the outer ring of the coil by increasing the rolling speed of the tail of the strip during the rolling process, so as to compensate for the difference between the inner and outer rings of the coil and the ambient temperature.
[0009] The control method is used to optimize the rolling annealing process of hot-rolled strip, and the control method includes system joint control of a thermoelectric convexity meter, a pyrometer, and a rolling control secondary system.
[0010] The strip is a hot-rolled 1xxx series strip with a thickness of 3.5~4.5mm. The control method compensates for the difference between the inner ring, outer ring and ambient temperature of the coil, so that in the rolling annealing process, the temperatures of the inner ring, middle section and outer ring of the coil tend to be consistent and can be maintained at 310~320℃, and the insulation time is greater than 2 hours, so as to improve the texture fineness and uniformity of the coil material organization.
[0011] The control method is deployed in the production process of hot finished rolled strip of the rolling mill train, and a gradient temperature control module is added to the secondary rolling control system of the rolling mill train. By setting the target temperature of the strip head and the target temperature of the strip tail, the difference between the inner ring and the outer ring of the coil and the ambient temperature is compensated; and according to the needs, a uniform linear transition of the temperature distribution is achieved within the predetermined length or coil diameter range of the rolling process; The hot finished rolling strip production process is provided with a pyrometer at the finishing rolling exit to measure the strip temperature at the finishing rolling exit, and the measured strip actual temperature is compared with the target temperature set by the gradient temperature control module to control the rolling speed of the finishing rolling production process. If the measured strip temperature is lower than the target temperature, the rolling speed is increased; if the measured strip temperature is higher than the target temperature, the rolling speed is reduced, so as to ensure that the temperature of the aluminum coil produced by the hot finished rolling strip is within the temperature range set by the gradient temperature control module.
[0012] When the control method performs temperature compensation on the inner ring of the coil, the target temperature of the produced strip is compensated in advance in the program control of the rolling mill. Specifically, the target temperature of the strip head is set higher for the strip that is wound around the inner ring of the coil for a predetermined number of times, and the temperature of the inner ring is increased by increasing the rolling speed of the strip head.
[0013] When the control method performs temperature compensation on the outer ring of the coil, in the program control of the rolling mill, the target temperature of the tail of the strip is increased according to a preset slope by using a gradient temperature control module, specifically: the strip after the coil diameter reaches a preset target is set as the tail of the strip, and after the rolling length reaches the strip length at which the coil diameter reaches a preset target, the temperature control program of the gradient temperature module is started, and the acceleration amplitude of the rolling speed is controlled to achieve a gradual gradient temperature increase at the tail of the strip, that is, the target temperature of the strip in the outer ring area of the coil is set in advance, and the outer ring temperature is increased by increasing the rolling speed of the tail of the strip, so that the target temperature of the tail of the strip is gradually increased according to the preset slope.
[0014] The strip is a hot-rolled 1xxx series strip with a thickness of 3.5 to 4.5 mm; The gradient temperature control module automatically compensates for the heat exchange loss of the inner and outer rings of the coil to achieve a stable state of static recrystallization in the annealing process after finishing rolling, so as to obtain recrystallized grains with uniform structure, and improve material defects such as thickness difference and uneven structure. In the finishing rolling production process of the rolling mill, the relationship between the rolling acceleration value and the temperature is: In the setting of the gradient temperature control module, the greater the deviation between the actual temperature of the strip and the target temperature, the greater the acceleration of the finishing speed adjustment process; if the currently set rolling speed is higher, the temperature control acceleration is also greater, so as to increase the speed at which the actual temperature reaches the target value, while preventing the overshoot of the finishing speed from causing the rolling speed to oscillate.
[0015] In the setting of the gradient temperature control module, when the three conditions are met at the same time: the final rolling temperature control function is turned on, the deviation between the measured temperature and the target temperature is greater than 10°C, and the strip rolling length is greater than 60 meters, the temperature control program of the gradient temperature control module will adjust the final temperature of the product by controlling the acceleration of the main motor through the temperature deviation.
[0016] The gradient temperature control module controls the motor by controlling the main motor inverter and main motor encoder of the rolling mill to make the actual speed of the finishing process consistent with the set speed, so as to adjust the hot finishing production speed and realize the control of the strip temperature in the current rolling process; When the actual speed of the main motor is inconsistent with the set target speed, the temperature control program will automatically adjust the motor acceleration according to the amplitude of the speed deviation to prevent the thickness deviation of the aluminum coil caused by excessive speed changes.
[0017] The strip material is a CTP hot-rolled billet with a final rolling temperature of 310°C, and the strip material is a hot-rolled 1xxx series strip material with a thickness of 3.5-4.5 mm. During the finishing rolling process, the heat exchange between the inner ring of the coil and the reel, the heat exchange between the outer ring of the coil and the surrounding environment, and the heat exchange between the coil and the saddle base when the coil is stored in the saddle are all heat exchanges in a natural cooling mode; The temperature uniformity control method for the inner and outer rings of the aluminum plate and strip coil starts the gradient temperature compensation function of the control system when the strip coil diameter is rolled to three-quarters, that is, the coil diameter starts to be put into the compensation program from 1800mm, and the control system automatically adjusts the rolling speed, that is, V1, according to the heating slope, and ends when the coil diameter is 2300mm at the end of rolling, so that the temperature is increased from 310℃ in the core as required by the process to 320℃ at a slope of 1℃ / min, so as to fully ensure the recrystallization temperature and time of the outer ring of the coil during the natural cooling process.
[0018] The present invention provides a method for controlling the temperature uniformity of the inner and outer rings of a hot-rolled aluminum strip. The method can change the uneven temperature state of the inner and outer rings of the strip through gradient temperature input adjustment according to the final rolling temperature requirement of the hot-rolled strip, achieve the uniformity of the temperature of the inner and outer rings of the coil, and improve the organizational performance.
[0019] The present invention includes the joint control of a thermoelectric convexity meter, a pyrometer, a secondary rolling control system and other systems. By programming the temperature and speed, the temperature of the inner and outer ring strips is automatically controlled, which can compensate for the low temperature problem of the strips caused by environmental factors, and achieve temperature uniformity of the inner and outer ring strips during the annealing process, thereby improving the strip structure and performance.
[0020] In the present invention, the temperature compensation program can achieve uniform linear temperature transition within a certain length or coil diameter range as required (for example, at the tail of the strip).
[0021] The present invention can control the temperature uniformity of the inner and outer rings of the hot-rolled aluminum strip through a program that can realize automatic temperature control within a certain range, and realize stable operation of static recrystallization in the annealing process by automatically supplementing the heat loss of the inner and outer rings, thereby obtaining recrystallized grains with uniform structure and improving defects such as thickness difference and uneven structure. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] The present invention is further described in detail below with reference to the accompanying drawings and specific embodiments: Attached Figure 1 Schematic diagram of the embodiment of the present invention at the finish rolling exit (the coil diameter is 1200 mm at this time); Attached Figure 2 is another schematic diagram of an embodiment of the present invention at a finishing rolling exit; Attached Figure 3 It is a schematic diagram comparing the temperature distribution of the head of the coil strip using the present invention and the temperature distribution of the head of the coil strip not using the present invention; Attached Figure 4 It is a comparative schematic diagram of the temperature distribution at the tail of the coil strip using the present invention and the temperature distribution at the tail of the coil strip not using the present invention; Attached Figure 5 It is a schematic diagram comparing the tissue texture of a strip using the present invention and the tissue texture of a strip not using the present invention. DETAILED DESCRIPTION
[0023] As shown in the figure, a method for controlling the temperature uniformity of the inner and outer rings of an aluminum plate and strip coil is provided. The coil is formed by rolling a strip from an aluminum material. The head of the strip is located at the inner ring of the coil, and the tail of the strip is located at the outer ring of the coil. During the rolling process, the heat dissipation time at the inner ring of the coil is longer than that at the ring layer in the middle section of the coil, and the temperature difference between the temperature at the outer ring of the coil and the ambient temperature is greater than that at the ring layer in the middle section of the coil. The control method increases the temperature of the inner ring of the coil by increasing the rolling speed of the head of the strip during the rolling process, and increases the temperature of the outer ring of the coil by increasing the rolling speed of the tail of the strip during the rolling process, so as to compensate for the difference between the inner and outer rings of the coil and the ambient temperature.
[0024] The control method is used to optimize the rolling annealing process of hot-rolled strip, and the control method includes system joint control of a thermoelectric convexity meter, a pyrometer, and a rolling control secondary system.
[0025] The strip is a hot-rolled 1xxx series strip with a thickness of 3.5~4.5mm. The control method compensates for the difference between the inner ring, outer ring and ambient temperature of the coil, so that in the rolling annealing process, the temperatures of the inner ring, middle section and outer ring of the coil tend to be consistent and can be maintained at 310~320℃, and the insulation time is greater than 2 hours, so as to improve the texture fineness and uniformity of the coil material organization.
[0026] The control method is deployed in the production process of hot finished rolled strip of the rolling mill train, and a gradient temperature control module is added to the secondary rolling control system of the rolling mill train. By setting the target temperature of the strip head and the target temperature of the strip tail, the difference between the inner ring and the outer ring of the coil and the ambient temperature is compensated; and according to the needs, a uniform linear transition of the temperature distribution is achieved within the predetermined length or coil diameter range of the rolling process; The hot finished rolling strip production process is provided with a pyrometer at the finishing rolling exit to measure the strip temperature at the finishing rolling exit, and the measured strip actual temperature is compared with the target temperature set by the gradient temperature control module to control the rolling speed of the finishing rolling production process. If the measured strip temperature is lower than the target temperature, the rolling speed is increased; if the measured strip temperature is higher than the target temperature, the rolling speed is reduced, so as to ensure that the temperature of the aluminum coil produced by the hot finished rolling strip is within the temperature range set by the gradient temperature control module.
[0027] When the control method performs temperature compensation on the inner ring of the coil, the target temperature of the produced strip is compensated in advance in the program control of the rolling mill. Specifically, the target temperature of the strip head is set higher for the strip that is wound around the inner ring of the coil for a predetermined number of times, and the temperature of the inner ring is increased by increasing the rolling speed of the strip head.
[0028] When the control method performs temperature compensation on the outer ring of the coil, in the program control of the rolling mill, the target temperature of the tail of the strip is increased according to a preset slope by using a gradient temperature control module, specifically: the strip after the coil diameter reaches a preset target is set as the tail of the strip, and after the rolling length reaches the strip length at which the coil diameter reaches a preset target, the temperature control program of the gradient temperature module is started, and the acceleration amplitude of the rolling speed is controlled to achieve a gradual gradient temperature increase at the tail of the strip, that is, the target temperature of the strip in the outer ring area of the coil is set in advance, and the outer ring temperature is increased by increasing the rolling speed of the tail of the strip, so that the target temperature of the tail of the strip is gradually increased according to the preset slope.
[0029] The strip is a hot-rolled 1xxx series strip with a thickness of 3.5 to 4.5 mm; The gradient temperature control module automatically compensates for the heat exchange loss of the inner and outer rings of the coil to achieve a stable state of static recrystallization in the annealing process after finishing rolling, so as to obtain recrystallized grains with uniform structure, and improve material defects such as thickness difference and uneven structure. In the finishing rolling production process of the rolling mill, the relationship between the rolling acceleration value and the temperature is: In the setting of the gradient temperature control module, the greater the deviation between the actual temperature of the strip and the target temperature, the greater the acceleration of the finishing speed adjustment process; if the currently set rolling speed is higher, the temperature control acceleration is also greater, so as to increase the speed at which the actual temperature reaches the target value, while preventing the overshoot of the finishing speed from causing the rolling speed to oscillate.
[0030] In the setting of the gradient temperature control module, when the three conditions are met at the same time: the final rolling temperature control function is turned on, the deviation between the measured temperature and the target temperature is greater than 10°C, and the strip rolling length is greater than 60 meters, the temperature control program of the gradient temperature control module will adjust the final temperature of the product by controlling the acceleration of the main motor through the temperature deviation.
[0031] The gradient temperature control module controls the motor by controlling the main motor inverter and main motor encoder of the rolling mill to make the actual speed of the finishing process consistent with the set speed, so as to adjust the hot finishing production speed and realize the control of the strip temperature in the current rolling process; When the actual speed of the main motor is inconsistent with the set target speed, the temperature control program will automatically adjust the motor acceleration according to the amplitude of the speed deviation to prevent the thickness deviation of the aluminum coil caused by excessive speed changes.
[0032] The strip material is a CTP hot-rolled billet with a final rolling temperature of 310°C, and the strip material is a hot-rolled 1xxx series strip material with a thickness of 3.5-4.5 mm. During the finishing rolling process, the heat exchange between the inner ring of the coil and the reel, the heat exchange between the outer ring of the coil and the surrounding environment, and the heat exchange between the coil and the saddle base when the coil is stored in the saddle are all heat exchanges in a natural cooling mode; The temperature uniformity control method for the inner and outer rings of the aluminum plate and strip coil starts the gradient temperature compensation function of the control system when the strip coil diameter is rolled to three-quarters, that is, the coil diameter starts to be put into the compensation program from 1800mm, and the control system automatically adjusts the rolling speed, that is, V1, according to the heating slope, and ends when the coil diameter is 2300mm at the end of rolling, so that the temperature is increased from 310℃ in the core as required by the process to 320℃ at a slope of 1℃ / min, so as to fully ensure the recrystallization temperature and time of the outer ring of the coil during the natural cooling process.
[0033] Example: In this example, if Figure 1 , Figure 2 As shown in the figure, the hot finished rolling strip production is feedback controlled according to the final rolling temperature. That is, the strip temperature at the outlet is measured by the finishing exit pyrometer and compared with the set target temperature to control the finishing production speed. If the actual measured strip temperature is lower than the target temperature, the production speed is increased; if the actual measured strip temperature is higher than the target temperature, the production speed is reduced to ensure that the temperature of the aluminum coil produced by the finishing rolling is within the set temperature range.
[0034] After the strip is curled at the mandrel position, the inner ring directly contacts the curling mandrel, and the head of the strip is threaded slowly, so the head has a longer heat dissipation time. Therefore, after a roll of aluminum coil is produced, the temperature of the inner ring is lower than that of the outer ring. At the same time, there is a huge difference between the temperature of the outer ring of the aluminum coil and the ambient temperature. Affected by heat transfer, the heat loss of the outer ring aluminum coil far exceeds that of the middle part, so the temperature of the outer ring aluminum coil drops faster. Since the lower final rolling temperature will affect the static recrystallization process, it will lead to problems such as unqualified product performance. In this example, in order to solve the problem of low temperature of the inner and outer rings of the finished aluminum coil head, a gradient temperature control function is added to the program. That is, the target temperature of the production strip is compensated in advance in the program control. The method is: 1. The target temperature is set higher within a certain number of inner ring windings, and the inner ring temperature is increased by increasing the head rolling speed.
[0035] 2. To solve the problem of low outer ring temperature of finished aluminum coil, a gradient temperature compensation function is added to the program after the hot rolled strip is rolled to a certain coil diameter. That is, after the coil diameter reaches a certain target, the gradient temperature control program is put into use to achieve gradual gradient temperature increase. That is, by setting the target temperature of the outer ring production strip in advance on the operation screen, the outer ring temperature is increased by increasing the tail rolling speed.
[0036] like Figure 3 As shown, after the gradient temperature function is turned on, the target temperature of the strip head is higher, and the pyrometer measured temperature of the strip head with the gradient temperature function turned on is higher than that of the strip without the gradient temperature function turned on.
[0037] like Figure 4 As shown, after the gradient temperature function is turned on, the target temperature at the tail of the strip is gradually increased according to the preset slope. The pyrometer measured temperature at the tail of the coil with the gradient temperature function turned on is higher than that of the coil without the gradient temperature function turned on.
[0038] In this example, the control technology uses the electrical control program to perform temperature compensation with preset values, and adjusts the exit rolling speed of the finishing rolling process F3 through exit pyrometer temperature control, thereby controlling the strip final rolling temperature to reach the predetermined target.
[0039] Since the production speed of the finishing mill is controlled by the difference between the actual temperature of the aluminum coil and the target temperature, when the temperature of the strip measured by the pyrometer is lower than the set target temperature, the production speed is increased, and vice versa. The deviation between the actual temperature and the target temperature will directly affect the set speed of the main motor. As the set speed of the motor changes, the main motor inverter and the main motor encoder can be used to control the actual speed of the motor to be consistent with the set speed, thereby adjusting the hot finishing production speed and ultimately achieving control of the strip temperature during the current rolling process.
[0040] When the actual speed of the main motor is inconsistent with the target speed, the program will automatically adjust the motor acceleration according to the magnitude of the speed deviation to prevent problems such as thickness deviation of the aluminum coil caused by excessive speed changes.
[0041] The setting range of the gradient temperature function and the amplitude of the temperature change are adjusted by the actual measurement results of the produced strip. The operator sets whether the gradient temperature function is currently used, the temperature gradient range and the effective range of the function on the HMI screen. By measuring the inner and outer ring temperatures of the current aluminum coil and testing the performance of aluminum coils in different rings of the product, it can be determined whether the product quality has been improved, so as to further optimize the set value and ultimately achieve the purpose of improving product quality.
[0042] In this case, the final rolling temperature of the CTP hot-rolled billet is 310℃. In the actual production process, the outer ring of the coil is affected by the ambient temperature and the temperature drops significantly, especially in the natural cooling process of the flat warehouse, where the contact part with the saddle is more affected by heat transfer. If the outer ring drops rapidly due to heat exchange with the environment, and the strip temperature is lower than the recrystallization temperature, the self-recovery recrystallization annealing will stop, and the microstructure and performance will be uneven. The subsequent cold rolling will produce defects such as thickness difference due to different deformation resistance of the strip during rolling.
[0043] In order to ensure that the recrystallization temperature and time of the outer ring of the coil are close to those of the inner ring of the coil, this embodiment uses the gradient temperature compensation technology when the coil diameter of the strip is rolled to three-quarters, that is, the coil diameter starts to be put into use when it is 1800mm, and the control system automatically adjusts the rolling speed (i.e. V1) according to the heating slope, and ends when the coil diameter (2300mm) is rolled. The temperature is increased from 310℃ in the core part according to the process requirement to 320℃ at a slope of 1℃ / min, which can fully ensure the recrystallization temperature and time of the outer ring of the coil during the natural cooling process. Vice versa, the temperature uniformity control of the inner ring can also be controlled by this technology.
[0044] In this example, the grain size of the hot-rolled 1xxx series 3.5~4.5mm thick strip is greatly affected by the final rolling temperature and the length of time kept at the recrystallization temperature. The higher the temperature, the faster the recrystallization and the more uniform the grains; the longer the holding time, the more uniform the grain growth. Of course, too high a temperature and too long a holding time will also cause adverse effects such as coarse grains. Therefore, to ensure that the strip can be kept at a suitable temperature for a suitable time is the key point of this technology control.
[0045] To achieve self-recovery recrystallization annealing of the coil after hot rolling, the final rolling temperature of the hot rolled billet is usually controlled to be 20~30℃ higher than the recrystallization temperature.
[0046] In the traditional rolling process, after the final rolling temperature is set, the rolling processing rate and rolling speed between the finishing mill stands are carried out according to fixed parameters. When the environmental factors are not compensated, that is, the first pass is 32→16mm, the second pass is 16→8mm, and the third pass is 8→4.0mm. The final rolling temperature is set to 310℃, and the whole coil rolling process remains unchanged. After the rolling is completed, due to the large temperature difference between the billet temperature and the environment, the coil temperature drops significantly. Therefore, the recrystallization time of the inner and outer rings is significantly shorter than that of the coil core, and the recrystallization of the inner and outer rings is not sufficient.
[0047] In this example, the temperature uniformity control method of the inner and outer rings of the aluminum plate and strip coil of the present invention is used, which comprehensively considers the heat exchange between the inner ring of the coil and the reel, the heat exchange between the outer ring of the coil and the surrounding environment, and the heat exchange between the coil and the saddle base when stored in the saddle. Through the temperature compensation program of this technology, the final rolling temperature of the inner and outer rings is appropriately increased, which can effectively extend the recrystallization time of the inner and outer rings, eliminate the influence of environmental factors, improve the difference in the structure of the aluminum coil core and the inner and outer rings, and achieve the purpose of improving the performance of aluminum materials.
[0048] like Figure 5As shown, when the present invention is not used, when the annealing temperature is lower than 300°C, the self-recovery recrystallization rate of the hot-rolled strip is significantly reduced, and the final microstructure and texture of the strip is relatively coarse; when the temperature uniformity control method of the inner and outer rings of the aluminum plate and strip coil of the present invention is used, when the annealing temperature is maintained at 310-320°C, the holding time is greater than 2 hours, and the final microstructure and texture of the strip is relatively fine and uniform.
Claims
1. A method for controlling the temperature uniformity of inner and outer rings of an aluminum plate and strip coil, characterized in that: The coil is formed by rolling a strip rolled from an aluminum material, the strip head is located at the inner ring of the coil, and the strip tail is located at the outer ring of the coil. During the rolling process, the heat dissipation time at the inner ring of the coil is longer than that of the ring layer in the middle section of the coil, and the temperature difference between the temperature at the outer ring of the coil and the ambient temperature is greater than that of the ring layer in the middle section of the coil. The control method increases the temperature of the inner ring of the coil by increasing the rolling speed of the strip head during the rolling process, and increases the temperature of the outer ring of the coil by increasing the rolling speed of the strip tail during the rolling process, so as to compensate for the difference between the inner ring, outer ring and ambient temperature of the coil.
2. The method for controlling the temperature uniformity of the inner and outer rings of an aluminum plate and strip coil according to claim 1, characterized in that: The control method is used to optimize the rolling annealing process of hot-rolled strip, and the control method includes system joint control of a thermoelectric convexity meter, a pyrometer, and a rolling control secondary system.
3. The method for controlling the temperature uniformity of the inner and outer rings of an aluminum plate and strip coil according to claim 2, characterized in that: The strip is a hot-rolled 1xxx series strip with a thickness of 3.5~4.5mm. The control method compensates for the difference between the inner ring, outer ring and ambient temperature of the coil, so that in the rolling annealing process, the temperatures of the inner ring, middle section and outer ring of the coil tend to be consistent and can be maintained at 310~320℃, and the insulation time is greater than 2 hours, so as to improve the texture fineness and uniformity of the coil material organization.
4. The method for controlling the temperature uniformity of inner and outer rings of an aluminum plate and strip coil according to claim 1, characterized in that: The control method is deployed in the production process of hot finished rolled strip of the rolling mill train, and a gradient temperature control module is added to the secondary rolling control system of the rolling mill train. By setting the target temperature of the strip head and the target temperature of the strip tail, the difference between the inner ring and the outer ring of the coil and the ambient temperature is compensated; and according to the needs, a uniform linear transition of the temperature distribution is achieved within the predetermined length or coil diameter range of the rolling process; The hot finished rolling strip production process is provided with a pyrometer at the finishing rolling exit to measure the strip temperature at the finishing rolling exit, and the measured strip actual temperature is compared with the target temperature set by the gradient temperature control module to control the rolling speed of the finishing rolling production process. If the measured strip temperature is lower than the target temperature, the rolling speed is increased; if the measured strip temperature is higher than the target temperature, the rolling speed is reduced, so as to ensure that the temperature of the aluminum coil produced by the hot finished rolling strip is within the temperature range set by the gradient temperature control module.
5. The method for controlling the temperature uniformity of inner and outer rings of an aluminum plate and strip coil according to claim 4, characterized in that: When the control method performs temperature compensation on the inner ring of the coil, the target temperature of the produced strip is compensated in advance in the program control of the rolling mill. Specifically, the target temperature of the strip head is set higher for the strip that is wound around the inner ring of the coil for a predetermined number of times, and the temperature of the inner ring is increased by increasing the rolling speed of the strip head.
6. The method for controlling the temperature uniformity of inner and outer rings of an aluminum plate and strip coil according to claim 4, characterized in that: When the control method performs temperature compensation on the outer ring of the coil, in the program control of the rolling mill, the target temperature of the tail of the strip is increased according to a preset slope by using a gradient temperature control module, specifically: the strip after the coil diameter reaches a preset target is set as the tail of the strip, and after the rolling length reaches the strip length at which the coil diameter reaches a preset target, the temperature control program of the gradient temperature module is started, and the acceleration amplitude of the rolling speed is controlled to achieve a gradual gradient temperature increase at the tail of the strip, that is, the target temperature of the strip in the outer ring area of the coil is set in advance, and the outer ring temperature is increased by increasing the rolling speed of the tail of the strip, so that the target temperature of the tail of the strip is gradually increased according to the preset slope.
7. A method for controlling the temperature uniformity of inner and outer rings of an aluminum plate and strip coil according to claim 5 or 6, characterized in that: The strip is a hot-rolled 1xxx series strip with a thickness of 3.5 to 4.5 mm; The gradient temperature control module automatically compensates for the heat exchange loss of the inner and outer rings of the coil to achieve a stable state of static recrystallization in the annealing process after finishing rolling, so as to obtain recrystallized grains with uniform structure, and improve material defects such as thickness difference and uneven structure. In the finishing rolling production process of the rolling mill, the relationship between the rolling acceleration value and the temperature is: In the setting of the gradient temperature control module, the greater the deviation between the actual temperature of the strip and the target temperature, the greater the acceleration of the finishing speed adjustment process; if the currently set rolling speed is higher, the temperature control acceleration is also greater, so as to increase the speed at which the actual temperature reaches the target value, while preventing the overshoot of the finishing speed from causing the rolling speed to oscillate.
8. The method for controlling the temperature uniformity of inner and outer rings of an aluminum plate and strip coil according to claim 7, characterized in that: In the setting of the gradient temperature control module, when the three conditions are met at the same time: the final rolling temperature control function is turned on, the deviation between the measured temperature and the target temperature is greater than 10°C, and the strip rolling length is greater than 60 meters, the temperature control program of the gradient temperature control module will adjust the final temperature of the product by controlling the acceleration of the main motor through the temperature deviation.
9. The method for controlling the temperature uniformity of inner and outer rings of an aluminum plate and strip coil according to claim 7, characterized in that: The gradient temperature control module controls the motor by controlling the main motor inverter and main motor encoder of the rolling mill to make the actual speed of the finishing process consistent with the set speed, so as to adjust the hot finishing production speed and realize the control of the strip temperature in the current rolling process; When the actual speed of the main motor is inconsistent with the set target speed, the temperature control program will automatically adjust the motor acceleration according to the amplitude of the speed deviation to prevent the thickness deviation of the aluminum coil caused by excessive speed changes.
10. The temperature uniformity control method of an aluminum plate and strip coil inner and outer ring temperature of an aluminum plate and strip coil according to claim 7, characterized in that: The strip material is a CTP hot-rolled billet with a final rolling temperature of 310°C, and the strip material is a hot-rolled 1xxx series strip material with a thickness of 3.5-4.5 mm. During the finishing rolling process, the heat exchange between the inner ring of the coil and the reel, the heat exchange between the outer ring of the coil and the surrounding environment, and the heat exchange between the coil and the saddle base when the coil is stored in the saddle are all heat exchanges in a natural cooling mode; The temperature uniformity control method for the inner and outer rings of the aluminum plate and strip coil starts the gradient temperature compensation function of the control system when the strip coil diameter is rolled to three-quarters, that is, the coil diameter starts to be put into the compensation program from 1800mm, and the control system automatically adjusts the rolling speed, that is, V1, according to the heating slope, and ends when the coil diameter is 2300mm at the end of rolling, so that the temperature is increased from 310℃ in the core as required by the process to 320℃ at a slope of 1℃ / min, so as to fully ensure the recrystallization temperature and time of the outer ring of the coil during the natural cooling process.