Roll forming method, apparatus, device and medium for strip steel

Abstract

The application discloses a strip steel roll forming method, device, equipment and medium, and belongs to the technical field of metallurgy. The method comprises the following steps: obtaining the identification code and feeding speed of the strip steel after the strip steel enters a roll forming production line; determining the target heating power of the strip steel according to the feeding speed; if the distance between the to-be-formed fillet area of the strip steel and the target position corresponding to the identification code is less than a preset distance threshold, controlling the heating device at the target position to heat the to-be-formed fillet area at the target heating power, so that the to-be-formed fillet area is roll formed into a fillet shape, and the target fillet radius of the fillet shape is less than a preset radius threshold; and bending the heated to-be-formed fillet area into a fillet shape with a fillet radius of the target fillet radius. The method can prevent the to-be-formed fillet area from cracking and rebounding when being bent into a shape with a small fillet radius after being heated, and meanwhile, the product qualification rate is not affected.

Description

Technical Field

[0001] This application relates to the field of metallurgical technology, and in particular to a method, apparatus, equipment and medium for roll forming of steel strip. Background Technology

[0002] With the current trend towards lightweighting in the automotive industry, ultra-high-strength steel strip (UHSS) with tensile strength exceeding 1000 MPa is being used more and more widely. However, when applying UHSS to roll forming, two key technical challenges are encountered: corner cracking and severe springback.

[0003] In the prior art, considering that micro-cracks, direct cracking or springback problems are prone to occur at the outer corner of the material when forming small fillet radii, the problem is solved by increasing the bending radius.

[0004] While this method can partially alleviate the aforementioned problems, it leads to a decrease in product qualification rate. Therefore, how to ensure product qualification rate during roll forming while preventing corner cracking and springback of the strip is a pressing technical problem that needs to be solved. Summary of the Invention

[0005] In view of the above problems, this application is made to provide a method, apparatus, equipment and medium for roll forming of strip steel to solve the above problems. By heating the area of ​​the strip steel to be bent into a small radius, the material plasticity of the strip steel in that area is improved, so that when the area is heated and then bent into a shape with a small radius, cracking and springback will not occur, and the product qualification rate will not be affected.

[0006] In a first aspect, this application provides a method for roll forming of steel strip, the method comprising: After the strip enters the roll forming production line, the identification code and feed speed of the strip are obtained; The target heating power of the strip is determined based on the feed rate; If the distance between the rounded corner area to be formed of the strip and the target position corresponding to the identification code is less than a preset distance threshold, then the heating device at the target position is controlled to heat the rounded corner area to be formed with the target heating power. After the rounded corner area to be formed is rolled, it becomes a rounded corner shape and the target rounded corner radius of the rounded corner shape is less than a preset radius threshold. The heated area to be formed is bent into a rounded shape with a radius equal to the target radius.

[0007] Optionally, determining the target heating power of the strip based on the feed rate includes: The target heating power of the strip corresponding to the feed speed is determined, and the feed speed is positively correlated with the target heating power.

[0008] Optionally, the method further includes: During the heating process, the thickness, yield strength, and real-time temperature of the strip are obtained; The target temperature of the fillet region to be formed is determined based on the thickness, the feed rate, the yield strength, and the target fillet radius. If the real-time temperature after a set time is less than the target temperature after the start of heating, the heating power of the heating device is increased until the real-time temperature after the increased heating power is greater than or equal to the target temperature.

[0009] Optionally, determining the target temperature of the fillet region to be formed based on the thickness, the feed rate, the yield strength, and the target fillet radius includes: Obtain the first weight corresponding to the thickness, the second weight corresponding to the feed rate, the third weight corresponding to the yield strength, and the fourth weight corresponding to the target fillet radius; The first compensation temperature is determined based on the thickness and the first weight; The second compensation temperature is determined based on the feed rate and the second weight. The third compensation temperature is determined based on the yield strength and the third weight. The fourth compensation temperature is determined based on the target fillet radius and the fourth weight. The target temperature of the rounded corner area to be formed is determined based on the sum of the preset reference temperature, the first compensation temperature, the second supplementary temperature, the third compensation temperature, and the fourth supplementary temperature.

[0010] Optionally, determining the second compensation temperature based on the feed rate and the second weight includes: The product of the natural logarithm of the feed rate and the second weight is used as the second compensation temperature.

[0011] Optionally, determining the third compensation temperature based on the yield strength and the third weight includes: The product of the yield strength and the third weight is taken as the third compensation temperature.

[0012] Optionally, determining the fourth compensation temperature based on the target fillet radius and the fourth weight includes: The product of the reciprocal of the target fillet radius and the fourth weight is used as the fourth compensation temperature.

[0013] Secondly, this application provides a strip steel roll forming apparatus, the apparatus comprising: The first acquisition module is used to acquire the identification code and feed speed of the strip after it enters the roll forming production line. The first determining module is used to determine the target heating power of the strip steel based on the feed speed; The control module is used to control the heating device at the target position to heat the rounded corner area to be formed with the target heating power if the distance between the rounded corner area to be formed of the strip and the target position corresponding to the identification code is less than a preset distance threshold. The rounded corner area to be formed is rolled into a rounded shape and the target rounded corner radius of the rounded shape is less than a preset radius threshold. The bending module is used to bend the heated rounded corner area into a rounded shape with a radius equal to the target rounded corner radius.

[0014] Thirdly, this application provides an electronic device, including: a memory and a processor, the memory and the processor being communicatively connected to each other, the memory storing computer instructions, and the processor executing the computer instructions to perform the method as described in the first aspect.

[0015] Fourthly, this application provides a computer-readable storage medium storing computer instructions for causing the computer to perform the method described in the first aspect.

[0016] The technical solutions provided in this application embodiment have at least the following technical effects or advantages: This application provides a method, apparatus, equipment, and medium for roll forming of steel strip. When the steel strip enters the roll forming production line, its identification code and feed speed are acquired. The identification code distinguishes the position of the fine bending stage, and the feed speed indicates the duration of the strip passing through the heating device. Based on the feed speed, the target heating power of the steel strip is determined; different heating durations result in different target heating powers. If the distance between the rounded corner area to be formed and the target position corresponding to the identification code is less than a preset distance threshold, the heating device at the target position is controlled to heat the rounded corner area to be formed at the target heating power. That is, the rounded corner area to be formed is heated when it moves to the heating area corresponding to the heating device. After heating, the plasticity of the rounded corner area to be formed changes. At this point, bending the heated rounded corner area into a rounded shape with a radius equal to the target radius prevents cracking and rebound. Specifically, the rounded corner area to be formed is a rounded shape after roll forming, and the target radius of the rounded corner shape is less than a preset radius threshold. This method improves the material plasticity of the strip by heating the area where the strip is to be bent into a small radius, so that cracking and springback will not occur when the area is heated and then bent into a small radius shape, and the product qualification rate will not be affected.

[0017] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0018] Various other advantages and benefits will become apparent to those skilled in the art upon reading the following detailed description of preferred embodiments. The accompanying drawings are for illustrative purposes only and are not intended to limit the scope of this application. Furthermore, the same reference numerals denote the same parts throughout the drawings. In the drawings: Figure 1 This is a flowchart of a strip roll forming method provided in an embodiment of this application; Figure 2 This is a schematic diagram of a closed cross section that is approximately square-shaped, according to an embodiment of this application. Figure 3 This is a structural block diagram of a strip roll forming apparatus provided in an embodiment of this application. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in further detail below with reference to the accompanying drawings. It should be understood that the embodiments of this disclosure and the specific features in the embodiments are detailed descriptions of the technical solutions of this application, rather than limitations on the technical solutions of this application. Unless otherwise specified, the embodiments of this application and the technical features in the embodiments can be combined with each other.

[0020] Before providing a detailed description of the strip roll forming method provided in the embodiments of this application, a brief introduction to its application scenarios will be given first.

[0021] Roll forming is a highly efficient continuous plastic forming process that uses multiple sequentially arranged forming rolls to gradually bend metal strip into the desired complex cross-sectional shape. It is widely used in the automotive, construction, and aerospace industries. With the current trend towards lightweighting in the automotive industry, ultra-high strength steel (UHSS) with tensile strength exceeding 1000 MPa is being used more and more extensively.

[0022] However, applying ultra-high strength steel to roll forming presents two major technical challenges: corner cracking and severe springback. Ultra-high strength steel typically exhibits low elongation and extremely high yield strength. During roll forming, especially when forming small corner radii, micro-cracks or direct cracking easily occur at the outer corners of the material. Furthermore, significant elastic recovery occurs after unloading, causing a severe deviation between the final geometry of the formed part and the die surface design, making it difficult to control product dimensional accuracy.

[0023] In the existing technology, the industry mostly adopts passive response strategies to the above problems, such as increasing the bending radius, but this strategy will lead to a decrease in product qualification rate.

[0024] Therefore, how to ensure the product qualification rate during roll forming while preventing the strip from cracking at the rounded corners and springback is a technical problem that urgently needs to be solved.

[0025] Figure 1 This is a flowchart of a strip roll forming method provided in an embodiment of this application, as shown below. Figure 1 As shown, the method includes: Step S110: After the strip enters the roll forming production line, obtain the strip's identification code and feed speed.

[0026] In this embodiment, strips with different identification codes need to be bent into different geometric shapes. The number of bending passes required for different geometric shapes may also be different, and the degree of bending of the strip may also be different for each pass. Therefore, they can be distinguished by the identification code. The identification code can be recorded on the product process card. Before production, the data on the product process card will be input into the database of the production system. When needed, it can be retrieved from the database. The database also stores the material parameters of the strip and the target geometric parameters corresponding to the strips with different identification codes. The target geometric parameters include the shape to be bent into, the size of the fillet, etc. The feed speed of the strip is the moving speed of the strip on the roll forming production line.

[0027] Step S120: Determine the target heating power of the strip based on the feed rate.

[0028] In this embodiment, a heating device is used to heat the rounded corner area of ​​the strip to be formed. Since the heating device is fixed and cannot be moved, the faster the strip feeds, the shorter the time the rounded corner area takes to pass through the heating device, and the shorter the heating time. Therefore, using the same target heating power for strips with different feed speeds results in a worse heating effect with higher feed speeds. To ensure consistent heating, the target heating power is determined based on the feed speed to ensure uniform heating for strips with different feed speeds.

[0029] Step S130: If the distance between the rounded corner area to be formed of the strip and the target position corresponding to the identification code is less than a preset distance threshold, then control the heating device at the target position to heat the rounded corner area to be formed with the target heating power.

[0030] Among them, the rounded corner area to be formed is rolled into a rounded shape, and the target rounded corner radius of the rounded corner shape is less than the preset radius threshold.

[0031] In this embodiment, since strips with different identification codes will eventually be bent into different shapes, the number of bending passes required also varies. These bending passes are generally divided into pre-bending passes, intermediate forming passes, and fine bending passes, sequentially along the direction of strip movement. The heating device is typically located at the fine bending pass. Before fine bending, heating alters the material plasticity of the rounded corner area to be formed, preventing cracking and springback during the final fine bending. Therefore, the position of the heating device will be adjusted accordingly as the fine bending passes for strips with different identification codes are located. This position is recorded as the target position, hence different identification codes correspond to different target positions.

[0032] The heating device can be fixed on a rigid mounting bracket, which is fixed to the bearing seat of the roller in the precision bending stage. When the area to be formed (rounded corner) moves to the target position, the heating device is positioned above or below the area to be formed, at a certain distance. This unique installation method allows the heating point of the heating device to be synchronously and in real-time tracked as the roller is pressed down, fundamentally ensuring that the heating device maintains precise spatial alignment with the area to be formed during dynamic adjustments on the production line. The heating device includes one of the following: induction heating coil, laser heating head, flame heating nozzle, and resistance heater. When using an induction heating coil, it can be designed as a contoured coil, with its contour matching the contour of the area to be formed, to improve heating efficiency and uniformity.

[0033] In this embodiment, the mounting bracket is equipped with a position fine-tuning mechanism for precisely adjusting and locking the relative distance and angle between the heating device and the strip during the system installation and commissioning phase. The distance between the heating device and the surface of the rounded corner area to be formed on the strip can be in the range of 1mm to 10mm.

[0034] Step S140: Bend the heated rounded corner area into a rounded shape with a radius equal to the target rounded corner radius.

[0035] In this embodiment, the rounded corner area to be formed is heated by a heating device before fine bending, which changes the plasticity of the material in the rounded corner area after heating. Therefore, cracking and springback will not occur when the rounded corner area with changed material plasticity is finally fine bent. The rounded corner area to be formed after fine bending is bent into a rounded corner shape with a rounded corner radius equal to the target rounded corner radius, thereby realizing the bending of the strip steel with a small rounded corner radius. This roll forming method does not affect the qualification rate of the finished product and does not cause cracking and springback.

[0036] Optionally, step S120 includes: Determine the target heating power of the strip corresponding to the feed speed, as the feed speed is positively correlated with the target heating power.

[0037] In this embodiment, the final temperature of strip steel at different feed speeds can be collected when heated by the same heating device with different target heating powers. The feed speed and target heating power corresponding to the desired final temperature can be selected, resulting in multiple sets of one-to-one correspondences between feed speeds and target heating powers. A relationship fitting test is performed on these multiple sets of feed speeds and target heating powers to obtain the corresponding relationship between feed speed and target heating power. This allows for the pre-determination of the correspondence between feed speed and target heating power. Based on this correspondence, the target heating power corresponding to the feed speed can be determined. Specifically, according to this correspondence, it can be found that the higher the feed speed, the shorter the heating time of the strip steel, and the higher the corresponding target heating power, in order to achieve the desired final heating effect.

[0038] The correspondence can be a relation table, a relation curve, or a relation formula, and this application does not limit it.

[0039] Optionally, the method also includes: Step S1301: During the heating process, obtain the thickness, yield strength, and real-time temperature of the strip. In this embodiment, the database stores material parameters including thickness and yield strength, so the thickness and yield strength of the strip can be obtained from the database. Real-time temperature can be detected using a temperature sensor or an infrared thermometer.

[0040] Step S1302: Determine the target temperature of the fillet area to be formed based on the thickness, feed rate, yield strength, and target fillet radius.

[0041] In this embodiment, the thickness of the strip, the feed rate, the yield strength, and the target fillet radius all affect the temperature change of the fillet area to be formed during the heating process. Therefore, the target temperature of the fillet area to be formed can be determined first based on the thickness, feed rate, yield strength, and target fillet radius. Then, the target heating power can be adjusted based on the target temperature so that the fillet area to be formed can be heated to the target temperature, and the heating effect can be met.

[0042] Optionally, step S1302 includes: The first step is to obtain the first weight corresponding to the thickness, the second weight corresponding to the feed rate, the third weight corresponding to the yield strength, and the fourth weight corresponding to the target fillet radius.

[0043] In this embodiment, the thickness, feed rate, yield strength, and target fillet radius have different effects on the temperature change of the fillet region to be formed during the heating process, so different weights can be assigned to the thickness, feed rate, yield strength, and target fillet radius.

[0044] This process involves heating strip steel at different feed rates, thicknesses, yield strengths, and target fillet radii (target fillet radius less than a radius threshold) to obtain strip steel at different test temperatures. The strip steel at these test temperatures is then bent into a target fillet shape with a fillet radius equal to the target fillet radius. The test temperature at which the strip steel does not crack or spring back after bending into the target fillet shape is recorded. The feed rate, thickness, yield strength, and target fillet radius corresponding to this test temperature are recorded one-to-one. The lowest temperature among all test temperatures at the same rate, thickness, yield strength, and target fillet radius is taken as the target temperature. This establishes a one-to-one correspondence between feed rate, thickness, yield strength, target fillet radius, and target temperature. Based on heat conduction theory, a large number of one-to-one correspondences of feed rate, thickness, yield strength, and target fillet radius are fitted with target temperature using multivariate nonlinear regression to obtain the degree of influence of each factor on the target temperature. The weights of each factor are then determined based on their respective degrees of influence, thus calibrating each weight.

[0045] For example, the higher the yield strength, the higher the target temperature needs to be set so that the plasticity of the rounded corner area to be formed after heating meets the requirements and that cracking and springback will not occur after precision bending.

[0046] The second step is to determine the first compensation temperature based on the thickness and the first weight.

[0047] In this embodiment, strips of different thicknesses have different heat capacities, different plasticities, and different heat dissipation rates. Therefore, based on the thickness and the first weight of the thickness's influence on the target temperature, a first compensation temperature is determined. The influence of heat capacity on plasticity and the influence of heat dissipation rate on the target temperature are compensated by the first compensation temperature, so that the plasticity of the fillet area to be formed at the final target temperature meets the requirements.

[0048] In this embodiment, based on heat conduction theory, a large number of one-to-one correspondences of feed rate, thickness, yield strength, and target fillet radius are fitted with target temperature using multivariate nonlinear regression. The fitting results show that the influence of thickness on target temperature is nonlinear, denoted by g(t). g(t) is a monotonically increasing function of thickness t, which can nonlinearly characterize the combined influence of heat capacity and heat dissipation rate of strips of different thicknesses on the temperature change of the strip during heating. Therefore, the first compensation temperature can be the product of g(t) and the first weight.

[0049] The third step is to determine the second compensation temperature based on the feed rate and the second weight.

[0050] In this embodiment, the feed rate affects the heating time of the fillet area to be formed. Therefore, a second compensation temperature is determined based on the feed rate and the second weight of the feed rate's influence on the target temperature. The difference in heating time is compensated for by the second compensation temperature.

[0051] Optional, the third step includes: The product of the natural logarithm of the feed rate and the second weight is used as the second compensation temperature.

[0052] In this embodiment of the application, based on the heat conduction theory, a large number of one-to-one corresponding feed rates, thicknesses, yield strengths, and target fillet radii are fitted with target temperatures using multivariate nonlinear regression. The fitting results show that the influence of feed rate on target temperature is logarithmic. Therefore, the product of the natural logarithm of the feed rate and the second weight can be directly used as the second compensation temperature.

[0053] Step 4: Determine the third compensation temperature based on the yield strength and the third weight.

[0054] In the embodiments of this application, strips with different yield strengths have different deformation resistances, and strips with different deformation resistances have different plasticity. Therefore, a third compensation temperature is determined based on the yield strength and the third weight of the influence of yield strength on the target temperature, and the influence of the difference in deformation resistance on plasticity is compensated by the third compensation temperature.

[0055] Optional, the fourth step includes: The product of the yield strength and the third weight is used as the third compensation temperature.

[0056] In this embodiment of the application, based on the heat conduction theory, a large number of one-to-one corresponding feed rates, thicknesses, yield strengths, and target fillet radii are fitted with target temperatures using multivariate nonlinear regression. The fitting results show a linear relationship between yield strength and target temperature. Therefore, the product of yield strength and the third weight is directly used as the third compensation temperature.

[0057] Step 5: Determine the fourth compensation temperature based on the target fillet radius and the fourth weight.

[0058] In this embodiment, the smaller the target fillet radius, the easier it is to crack and spring back during precision bending. Therefore, better plasticity after heating is required to avoid cracking and springback. Thus, a fourth compensation temperature is determined based on the target fillet radius and the fourth weight of the influence of the target temperature on the target fillet radius. Different fourth compensation temperatures are used to compensate for the different plasticity requirements of different target fillet radii.

[0059] Optional, step five includes: The product of the reciprocal of the target fillet radius and the fourth weight is used as the fourth compensation temperature.

[0060] In this embodiment of the application, based on the heat conduction theory, a large number of one-to-one corresponding feed rates, thicknesses, yield strengths, and target fillet radii are fitted with target temperatures using multivariate nonlinear regression. The fitting results show that the target fillet radius is negatively correlated with the target temperature. Therefore, the product of the reciprocal of the target fillet radius and the fourth weight can be used as the fourth compensation temperature.

[0061] Step 6: Determine the target temperature of the rounded corner area to be formed based on the sum of the preset reference temperature, first compensation temperature, second supplementary temperature, third compensation temperature and fourth supplementary temperature.

[0062] In this embodiment, based on the theory of heat conduction, a large number of one-to-one corresponding feed rates, thicknesses, yield strengths, and target fillet radii are fitted with target temperatures using multivariate nonlinear regression to obtain a fitting formula. The target temperature can be calculated using this fitting formula, which is as follows: T=T0+K1×g(t)+K2×ln(V)+K3×σ b +K4×(1 / R); Where T represents the target temperature, T0 represents the reference temperature (a constant), K1 represents the first weight, g(t) represents an increasing function with respect to thickness t, K2 represents the second weight, V represents the feed rate, K3 represents the third weight, and σ b K represents the yield strength, K4 represents the fourth weight, and R represents the target fillet radius. For example, the fitted... .

[0063] Step S1303: If the real-time temperature after a set time is less than the target temperature after the start of heating, increase the heating power until the real-time temperature after increasing the heating power is greater than or equal to the target temperature.

[0064] In this embodiment, the heating device at the target location heats the rounded corner area to be formed to the target temperature so that the plasticity of the rounded corner area after heating meets the requirements and cracking and springback will not occur during precision bending.

[0065] In this process, the heating device at the target location heats the rounded corner area to the target temperature. A temperature monitoring unit continuously monitors the real-time temperature of the rounded corner area and sends this information to the control unit. The control unit receives the real-time temperature from the monitoring unit and, if the real-time temperature is lower than the target temperature after a preset target time since the start of heating, determines the increase in heating power based on the difference between the real-time and target temperatures. The heating power is then increased until the increased real-time temperature is greater than or equal to the target temperature. This method of adjusting heating power eliminates steady-state errors and unknown disturbances, ensuring that the rounded corner area is heated to the target temperature. To significantly improve material plasticity while avoiding excessive phase transformation or strength loss due to excessively high temperatures, the target temperature must be within a set range. This range can be set according to the material properties of the strip. For example, the set range is 200℃ to 700℃.

[0066] In this embodiment, the temperature monitoring unit is located at the entrance side of the first bend after the target position and is aligned with the heating area of ​​the heating device. A non-contact infrared thermometer can be used as the temperature monitoring unit. The control unit is connected to the heating device, the temperature monitoring unit, and the main control system of the roll forming production line, forming the intelligent core of the system. The control unit also executes the strip roll forming method described in the above embodiment.

[0067] For example, taking the crossbeam of a new energy vehicle seat as an example, ultra-high strength steel of DP1470 is selected for the roll forming process. The thickness of the strip is 1.6mm, the tensile strength is 1470MPa, the yield strength is 1000MPa, and the target shape is a closed cross section of approximately U-shape. Figure 2 A schematic diagram of a closed cross section in an approximate U-shape provided in an embodiment of this application, as shown below. Figure 2 As shown, the top two rounded corner radii are R5, the bottom left rounded corner radius is R8, and the bottom right rounded corner radius is R3. R5 and R8 are both greater than the radius threshold, while R3 is less than the radius threshold. The rounded corner with R3 was prone to cracking during the roll forming process.

[0068] Next, to address the specific requirements of the R3 small fillet, the induction heating coil was made into a contour coil, with its inner contour precisely matching the curvature of the R3 fillet. The induction heating coil was directly fixed to the roller bearing seat of the precision bending stage via a rigid mounting bracket, with the installation distance precisely set to 2mm using a position fine-tuning mechanism. The production line started at a speed of 10m / min, the strip feed speed was 10m / min, and the calculated target heating power of the induction heating coil was 30kW. An infrared thermometer was placed on the entrance side of the precision bending stage to detect the real-time temperature of the R3 fillet area.

[0069] Based on the theory of heat conduction, a large number of one-to-one correspondences of feed rate, thickness, yield strength, and target fillet radius are fitted with target temperature using multivariate nonlinear regression. The fitted model formula is: T=T0+K1×g(t)+K2×ln(V)+K3×σ b +K4×(1 / R). Where, σ b =1000MPa, R=3mm, V=10m / min, t=1.6mm, With preset weighting coefficients: K1=0.15, K2=10, K3=25, K4=30, and a reference temperature T0=350℃, the target temperature T is calculated to be 599℃.

[0070] When the R3 rounded corner area of ​​the strip moves to the induction heating coil, the coil is activated and locally heats the R3 rounded corner area with a heating power of 30kW. An infrared thermometer monitors the real-time temperature of the heated R3 rounded corner area and sends this data back to the control unit. The control unit compares the real-time temperature after a set time with the target temperature. If the real-time temperature after the set time is lower than the target temperature, the increase in heating power is determined based on the difference. The sum of this increase and the target heating power is used as the new heating power, achieving precise closed-loop temperature control and ultimately stabilizing the real-time temperature of the R3 rounded corner area within the range of 599±10℃.

[0071] The R3 fillet area of ​​the precisely heated strip then enters the bending roller, where the R3 fillet is plastically deformed under conditions of significantly enhanced material plasticity. This achieves high-quality forming of the R3 fillet on a 1.6mm thin sheet of DP1470 ultra-high strength steel at a production line speed of 10m / min. No microcracks are found at the bent R3 fillet, and the product dimensional accuracy is controlled within ±0.5mm.

[0072] Based on the same concept, embodiments of the present invention also provide a strip roll forming apparatus. Figure 3 This is a structural block diagram of a strip steel roll forming apparatus provided in an embodiment of this application, as shown below. Figure 3As shown, the device 300 includes an acquisition module 301, a determination module 302, a control module 303, and a bending module 304.

[0073] The first acquisition module 301 is used to acquire the strip's identification code and feed speed after the strip enters the roll forming production line. The first determining module 302 is used to determine the target heating power of the strip based on the feed rate; The control module 303 is used to control the heating device at the target position to heat the rounded corner area to be formed with the target heating power if the distance between the rounded corner area to be formed and the target position corresponding to the identification code is less than a preset distance threshold. After the rounded corner area to be formed is rolled, it will be a rounded corner shape and the target rounded corner radius of the rounded corner shape will be less than a preset radius threshold. The bending module 304 is used to bend the heated rounded corner area into a rounded shape with a radius equal to the target rounded corner radius.

[0074] Optionally, the first determining module 302 is also used for: Determine the target heating power of the strip corresponding to the feed speed, as the feed speed is positively correlated with the target heating power.

[0075] Optionally, device 300 also includes: The second acquisition module is used to acquire the thickness, yield strength and real-time temperature of the strip during the heating process; The second determining module is used to determine the target temperature of the fillet area to be formed based on the thickness, feed rate, yield strength and target fillet radius; The adjustment module is used to increase the heating power of the heating device if the real-time temperature after a set time is less than the target temperature after the start of heating, until the real-time temperature after the increased heating power is greater than or equal to the target temperature.

[0076] Optionally, the second determining module includes: The acquisition unit is used to acquire the first weight corresponding to the thickness, the second weight corresponding to the feed rate, the third weight corresponding to the yield strength, and the fourth weight corresponding to the target fillet radius; The first determining unit is used to determine the first compensation temperature based on the thickness and the first weight. The second determining unit is used to determine the second compensation temperature based on the feed rate and the second weight. The third determining unit is used to determine the third compensation temperature based on the yield strength and the third weight. The fourth determining unit is used to determine the fourth compensation temperature based on the target fillet radius and the fourth weight. The fifth determining unit is used to determine the target temperature of the rounded corner area to be formed based on the sum of the preset reference temperature, the first compensation temperature, the second supplementary temperature, the third compensation temperature and the fourth supplementary temperature.

[0077] Optionally, the second determining unit is also used for: The product of the natural logarithm of the feed rate and the second weight is used as the second compensation temperature.

[0078] Optionally, the third determining unit is also used for: The product of the yield strength and the third weight is used as the third compensation temperature.

[0079] Optionally, the fourth determining unit is also used for: The product of the reciprocal of the target fillet radius and the fourth weight is used as the fourth compensation temperature.

[0080] It is understood that the device provided in the above embodiments is only illustrated by the division of the above functional modules. In actual applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above.

[0081] This invention also provides an electronic device that may include a processor and a memory, wherein the processor and the memory may be interconnected via a bus or other means.

[0082] The processor can be a central processing unit (CPU), or an application-specific integrated circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of this application, or it can be other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, or other chips, or combinations of the above types of chips.

[0083] Memory may include mass storage for data or instructions. For example, and not limitingly, memory may include hard disk drives (HDDs), floppy disk drives, flash memory, optical disks, magneto-optical disks, magnetic tape, or Universal Serial Bus (USB) drives, or combinations of two or more of these. Where appropriate, memory may include removable or non-removable (or fixed) media. Where appropriate, memory may be internal or external to an electronic device. In a particular embodiment, memory may be non-volatile solid-state memory.

[0084] In one instance, the memory may be read-only memory (ROM). In one instance, the ROM may be a mask-programmed ROM, a programmable ROM (PROM), an erasable PROM (EPROM), an electrically erasable PROM (EEPROM), an electrically rewritable ROM (EAROM), or flash memory, or a combination of two or more of these.

[0085] The processor reads and executes computer program instructions stored in the memory to implement any of the strip roll forming methods in the above embodiments.

[0086] In one example, the electronic device may further include a communication interface and a bus. The processor, memory, and communication interface are connected via the bus to communicate with each other. The communication interface is primarily used to enable communication between the various modules, devices, units, and / or equipment in the embodiments of this application. Where appropriate, the bus may include one or more buses.

[0087] Furthermore, in conjunction with the strip roll forming method in the above embodiments, this invention can be implemented using a computer-readable storage medium. This computer-readable storage medium stores computer program instructions; when executed by a processor, these computer program instructions implement any of the strip roll forming methods described in the above embodiments.

[0088] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, it can include the processes of the embodiments of the methods described above. The storage medium can be read-only memory (ROM), random access memory (RAM), flash memory, hard disk drive (HDD), or solid-state drive (SSD), etc.; the storage medium can also include combinations of the above types of memory.

[0089] The technical solutions described in the embodiments of this application have at least the following technical effects or advantages: This application provides a method, apparatus, equipment, and medium for roll forming of steel strip. When the steel strip enters the roll forming production line, its identification code and feed speed are acquired. The identification code distinguishes the position of the fine bending stage, and the feed speed indicates the duration of the strip passing through the heating device. Based on the feed speed, the target heating power of the steel strip is determined; different heating durations result in different target heating powers. If the distance between the rounded corner area to be formed and the target position corresponding to the identification code is less than a preset distance threshold, the heating device at the target position is controlled to heat the rounded corner area to be formed at the target heating power. That is, the rounded corner area to be formed is heated when it moves to the heating area corresponding to the heating device. After heating, the plasticity of the rounded corner area to be formed changes. At this point, bending the heated rounded corner area into a rounded shape with a radius equal to the target radius prevents cracking and rebound. Specifically, the rounded corner area to be formed is a rounded shape after roll forming, and the target radius of the rounded corner shape is less than a preset radius threshold. This method improves the material plasticity of the strip by heating the area where the strip is to be bent into a small radius, so that cracking and springback will not occur when the area is heated and then bent into a small radius shape, and the product qualification rate will not be affected.

[0090] Numerous specific details are set forth in the specification provided herein. However, it will be understood that embodiments of the invention may be practiced without these specific details. In some instances, well-known methods, structures, and techniques have not been shown in detail so as not to obscure the understanding of this specification.

[0091] Similarly, it should be understood that, in order to simplify this disclosure and aid in understanding one or more of the various aspects of the invention, in the above description of exemplary embodiments of the invention, various features of the invention are sometimes grouped together in a single embodiment, figure, or description thereof. However, this method of disclosure should not be construed as reflecting an intention that the claimed invention requires more features than are expressly recited in each claim. Rather, as reflected in the following claims, inventive aspects lie in fewer than all features of a single foregoing disclosed embodiment. Therefore, the claims following the detailed description are hereby expressly incorporated into this detailed description, wherein each claim itself is a separate embodiment of the invention.

[0092] It should be noted that the above embodiments are illustrative of the invention and not restrictive, and that those skilled in the art can devise alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses should not be construed as limiting the claims. The word "comprising" does not exclude the presence of components or steps not listed in the claims. The word "a" or "an" preceding a component does not exclude the presence of a plurality of such components. The invention can be implemented by means of hardware comprising several different components and by means of a suitably programmed computer. In the unit claims enumerating several means, several of these means may be embodied by the same item of hardware. The use of the words first, second, and third, etc., does not indicate any order. These words can be interpreted as names.

Claims

1. A method for roll forming of steel strip, characterized in that, The method includes: After the strip enters the roll forming production line, the identification code and feed speed of the strip are obtained; The target heating power of the strip is determined based on the feed rate; If the distance between the rounded corner area to be formed of the strip and the target position corresponding to the identification code is less than a preset distance threshold, then the heating device at the target position is controlled to heat the rounded corner area to be formed with the target heating power. After the rounded corner area to be formed is rolled, it becomes a rounded corner shape and the target rounded corner radius of the rounded corner shape is less than a preset radius threshold. The heated area to be formed is bent into a rounded shape with a radius equal to the target radius.

2. The strip forming method according to claim 1, characterized in that, Determining the target heating power of the strip based on the feed rate includes: The target heating power of the strip corresponding to the feed speed is determined, and the feed speed is positively correlated with the target heating power.

3. The strip forming method according to claim 1, characterized in that, The method further includes: During the heating process, the thickness, yield strength, and real-time temperature of the strip are obtained; The target temperature of the fillet region to be formed is determined based on the thickness, the feed rate, the yield strength, and the target fillet radius. If the real-time temperature after a set time is less than the target temperature after the start of heating, the heating power of the heating device is increased until the real-time temperature after the increased heating power is greater than or equal to the target temperature.

4. The strip forming method according to claim 3, characterized in that, Determining the target temperature of the fillet region to be formed based on the thickness, the feed rate, the yield strength, and the target fillet radius includes: Obtain the first weight corresponding to the thickness, the second weight corresponding to the feed rate, the third weight corresponding to the yield strength, and the fourth weight corresponding to the target fillet radius; The first compensation temperature is determined based on the thickness and the first weight; The second compensation temperature is determined based on the feed rate and the second weight. The third compensation temperature is determined based on the yield strength and the third weight. The fourth compensation temperature is determined based on the target fillet radius and the fourth weight. The target temperature of the rounded corner area to be formed is determined based on the sum of the preset reference temperature, the first compensation temperature, the second supplementary temperature, the third compensation temperature, and the fourth supplementary temperature.

5. The strip forming method according to claim 4, characterized in that, The determination of the second compensation temperature based on the feed rate and the second weight includes: The product of the natural logarithm of the feed rate and the second weight is used as the second compensation temperature.

6. The strip forming method according to claim 4, characterized in that, The step of determining the third compensation temperature based on the yield strength and the third weight includes: The product of the yield strength and the third weight is taken as the third compensation temperature.

7. The strip forming method according to claim 4, characterized in that, The step of determining the fourth compensation temperature based on the target fillet radius and the fourth weight includes: The product of the reciprocal of the target fillet radius and the fourth weight is used as the fourth compensation temperature.

8. A strip steel roll forming apparatus, characterized in that, The device includes: The first acquisition module is used to acquire the identification code and feed speed of the strip after it enters the roll forming production line. The first determining module is used to determine the target heating power of the strip steel based on the feed speed; The control module is used to control the heating device at the target position to heat the rounded corner area to be formed with the target heating power if the distance between the rounded corner area to be formed of the strip and the target position corresponding to the identification code is less than a preset distance threshold. The rounded corner area to be formed is rolled into a rounded shape and the target rounded corner radius of the rounded shape is less than a preset radius threshold. The bending module is used to bend the heated rounded corner area into a rounded shape with a radius equal to the target rounded corner radius.

9. An electronic device, characterized in that, include: A memory and a processor, the memory and the processor being communicatively connected to each other, the memory storing computer instructions, the processor executing the computer instructions to perform the method of any one of claims 1-7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer instructions for causing the computer to perform the method of any one of claims 1-7.

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