A double-curved stretch bending processing technology

Abstract

The application relates to the technical field of curtain wall and special-shaped section processing, and particularly discloses a double-curved stretch bending processing technology, which comprises the following steps: performing stretch bending evaluation through three-dimensional modeling and a BIM system; performing section optimization on a mold drawing and storing the mold drawing; designing a processing mold according to model parameters; manufacturing a filling strip according to a negative tolerance and installing a chuck mold; performing stretch bending forming and automatic springback compensation through numerical control equipment; comparing and correcting through three-dimensional scanning; performing profiling detection and correction on a special jig; performing aging treatment to improve material performance; performing surface treatment and protection; and uploading full-process data to a cloud platform to realize traceable management. Through the integration of digitalization and intelligentization technology, the application realizes high-precision and batch manufacturing of double-curved and special-shaped sections, and effectively solves the problems of difficult precision control and unstable quality in traditional processes.

Description

Technical Field

[0001] This invention relates to the field of curtain wall and irregular profile processing technology, specifically a hyperbolic bending process. Background Technology

[0002] With the development of modern architectural aesthetics, the application of hyperboloid and irregular structure curtain walls is becoming increasingly widespread, which puts forward higher requirements for the precision and efficiency of metal profile bending processing. When faced with complex spatial curves, traditional bending processes often result in insufficient precision of finished products due to problems such as material springback and cross-sectional deformation, making it difficult to meet the high standards of architectural appearance and sealing performance. The industry usually uses methods such as physical filling and mold constraint to suppress the deformation of profiles during bending, but these methods often rely on the experience of operators and have poor process stability.

[0003] Currently, Chinese patent application number CN202121022900.8 discloses an auxiliary bending device for a crossbeam cover profile, comprising a closed-cavity profile, a crossbeam cover, and fine sand; the crossbeam cover is inserted into the closed-cavity profile, and the fine sand fills the hollow space of the closed-cavity profile; during the bending process, the closed-cavity profile provides constraint to the bottom and sides of the crossbeam cover by contacting the bottom and sides, controlling the deformation of the bottom and sides of the crossbeam cover during the bending process, and the fine sand adheres to the other side of the crossbeam cover, providing constraint to the upper part of the crossbeam cover and preventing the upper part of the crossbeam cover from deforming; after bending, the profile is undamaged and the surface is free from uneven deformation.

[0004] However, existing technologies mostly rely on loose fillers such as fine sand when bending profiles. The density and uniformity of the filler are difficult to control precisely, which may lead to inconsistent support force and affect the forming accuracy. Furthermore, existing bending methods lack digital modeling and process feedback mechanisms, making it difficult to accurately predict and compensate for springback. They are also not adaptable to hyperbolic components with complex curvature changes. In addition, the entire bending process chain does not form a data closed loop, making quality traceability and process optimization difficult and unable to meet the requirements of mass production and high consistency. Summary of the Invention

[0005] The purpose of this invention is to provide a hyperbolic bending process to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: a hyperbolic bending process, comprising the following steps: S1. Modeling and Evaluation Phase: Using the 3D modeling software Rhino and its parametric plugin Grasshopper, combined with the Building Information Modeling (BIM) system, a 3D geometric model of the target component is constructed. Based on parameters such as the curvature radius of the building facade, bending arc length, and profile thickness, the tensile and bending performance is simulated and evaluated to identify potential processing difficulties and generate a tensile and bending process simulation model to guide production. S2. Module simplification and storage: The template of the profile section required for bending is optimized and simplified. The rounded corners that affect the model calculation efficiency and the success rate of Boolean operations are converted into right angles. Repeated line segments are deleted and broken lines are corrected to ensure that the section is closed. Then, the optimized profile section, its spatial reference point and unique number information are established in a one-to-one correspondence through the plugin (such as Kettybin) and stored in the central database for subsequent use. S3. Template Design: Based on the bending radius, torsion angle, and curvature change rate set in the model, design the corresponding template and process the bending template. S4. Filling section processing and mold installation: Fill with PE / PP board or stainless steel auxiliary strip according to the profile cross-section design, fill according to the negative tolerance of 0.5-1mm, install iron clamp mold and fix it stably with bolts or buckles; S5. Bending and forming control: The two ends of the profile are clamped by a CNC bending machine, and a controllable tension is applied to the middle section. The ratio of clamping force to tension is set according to the calibration parameters, and the radius is reduced by 7-15% according to the required curvature to compensate for springback. S6. Reverse scanning and correction: After bending, the formed part is scanned and modeled using a 3D scanner to generate a comparison report with the design model. For areas where the deviation exceeds ±1.5mm, local mechanical or manual adjustment is performed. S7. Three-dimensional correction and contour testing: Place the corrected profile on the three-dimensional contour testing fixture, test the fit of the sides and bottom, control the fit error to within 2mm, and use the three-dimensional correction machine to rotate and twist to adjust when there is a deviation. S8. Aging and Hardness Treatment: High-temperature aging treatment is carried out on qualified profiles at 180°C-200°C. After holding at the temperature for 4 hours, the profiles are naturally cooled and the hardness is tested to reach ≥12HB. S9. Surface treatment and protection: After manual grinding, painting test and surface inspection of the formed profiles, implement anti-scratch tape protection and double packaging in accordance with project requirements. S10. Data Traceability and Digital Closed Loop: Upload the above BIM modeling data, processing parameters, scanning reports and quality inspection records to the cloud process platform to achieve digital closed-loop management from design, manufacturing, inspection to feedback.

[0007] Preferably, in the modeling and evaluation stage, the Grasshopper program realizes panel decomposition, node extraction and parametric control through logical battery connection, so that the node information of each component includes profile template number, reference plane, stretch line and processing number, thereby realizing one-click batch drawing and data-driven modeling.

[0008] Preferably, the bending template in the template design includes an iron plate template and a wooden template. The iron plate template is processed by a roller mill by reducing the radius of the template by 90% according to the drawing. The wooden template is made by a carving machine by reducing the radius and angle proportionally, and then stacked and fixed according to the numbering.

[0009] Preferably, during the bending forming control process, the reduction ratio of the bending radius is automatically calculated based on the change in the target radius: When the radius is ≤1000mm, the reduction is 7%; when it is around 5000mm, the reduction is 12%; and when it is above 10000mm, the reduction is 15% to compensate for material springback and ensure curvature accuracy.

[0010] Preferably, in the reverse scanning and correction step, a three-dimensional scanning detection system is used to establish an STL surface file and compare it with the STEP file provided by the design; the deviation results generate a color deviation map, and the out-of-tolerance parts are locally adjusted to within the tolerance of ±1.5mm by a manual hydraulic device or a computer-controlled shaping machine; for overall shape deviations, a shaping machine or a three-dimensional correction machine is used for mechanical correction to ensure that the hyperbolic shape accuracy of the profile meets the tolerance requirements.

[0011] Preferably, during 3D calibration and contour testing, the fixture base adopts a standardized modular design, which can adapt to different specifications of materials by adjusting the bolt spacing; during the testing process, the fit of the side wall and the flatness of the bottom surface are mainly checked, and the system will automatically prompt for recalibration when the deviation exceeds 2mm.

[0012] Preferably, before the aging and hardening treatment, the bending parts need to be spatially positioned using a special fixing frame to prevent the material from undergoing secondary deformation due to hot air disturbance; after treatment, a hardness meter is used to test the hardness at three points: the end, middle, and apex of the profile, and the average value is calculated.

[0013] Preferably, during the surface treatment and protection process, the grinding is carried out using a pneumatic grinder with 60, 120, and 320 grit sandpaper for graded grinding; 20% of the painted samples are randomly inspected; the exposed surfaces are covered with special high-temperature resistant white protective tape and labeled with numbers according to project requirements.

[0014] Preferably, in the data traceability and closed-loop control, the cloud platform includes three types of interfaces: design end, production end, and testing end, and its information synchronization structure includes: Design parameters, processing logs, 3D inspection reports, aging furnace temperature records and hardness test results are recorded, and the entire process is traceable through a unique profile ID.

[0015] Preferably, the process is applicable to the bending and forming of single-curved, double-curved, and irregularly shaped twisted profiles, and can be widely used in the production of irregularly shaped building structural components such as double-curved unitized curtain walls, curved sunroofs, and three-dimensional decorative components, to achieve mass production, high precision, and traceable digital manufacturing.

[0016] Compared with the prior art, the beneficial effects of the present invention are: This invention constructs a technical solution integrating parametric BIM modeling, intelligent template design, precise springback compensation, and reverse scanning correction, realizing the digital and intelligent reshaping of the hyperbolic bending process. This process fundamentally changes the traditional processing mode that relies on worker experience and trial and error. Through digital twin technology, the entire bending process is accurately simulated and optimized in a virtual environment, thereby predicting and avoiding potential defects before physical manufacturing begins. In the physical processing stage, the precise springback control based on model data and the real-time three-dimensional scanning feedback correction mechanism form a dynamically optimized closed loop, which can actively compensate for errors caused by nonlinear deformation of materials. This ensures that even hyperbolic or irregularly shaped twisted components with extremely complex spatial relationships can achieve high forming accuracy and excellent batch consistency, significantly improving the engineering applicability and architectural expressiveness of the final product.

[0017] The front end of this invention employs a parametric design method, enabling one-click generation of processing drawings and process models based on architectural models, greatly shortening the technical preparation cycle. The intelligent template design and manufacturing in the middle transforms complex spatial geometry problems into precisely executable CNC instructions, achieving rapid response and accurate replication. The integrated 3D scanning and contour detection system at the end automates and intelligentizes quality inspection. The entire process is interconnected, minimizing manual intervention and waiting time in intermediate links, enabling complex irregular components to move from being machinable to efficient mass production. It demonstrates strong rapid response and delivery capabilities when facing large-scale and urgent engineering projects.

[0018] This invention enables unified traceability and in-depth data mining across the entire process through a cloud platform, achieving rapid source tracing and root cause analysis of quality issues, ensuring the superior quality of products leaving the factory, and enabling the production process to continuously self-optimize. Furthermore, this system breaks down information barriers between design and manufacturing, promoting efficient cross-professional and cross-departmental collaboration, allowing constraints in the manufacturing process to be fed back to the design stage in advance, optimizing design schemes from the source and improving process feasibility. Ultimately, this transparent and traceable manufacturing model provides a solid data foundation for subsequent on-site installation, operation and maintenance, and even the digital management of the entire building lifecycle, driving a profound transformation of the building manufacturing industry towards high-end and intelligent directions. Attached Figure Description

[0019] Figure 1 This is an overall flow chart of the hyperbolic bending process of the present invention; Figure 2 This is a schematic diagram of the contouring design for the template of this invention; Figure 3 This is a schematic diagram of the profile conformal testing method of the present invention; Figure 4 This is a schematic diagram of the analysis report generated by automatically comparing the model scanned by a 3D scanner with the original STEP format 3D model according to the present invention. Figure 5 This is a schematic diagram of the profile manufactured using the hyperbolic bending process of this invention. Detailed Implementation

[0020] To further explain the technical solution of the present invention, a detailed description is provided below through specific embodiments.

[0021] Please see Figures 1-5 This invention provides a hyperbolic bending process, such as... Figure 1 The overall process flow of the hyperbolic bending process of the present invention shown includes the following steps: S1. Modeling and Evaluation Phase: Using the 3D modeling software Rhino and its parametric plugin Grasshopper, combined with the Building Information Modeling (BIM) system, a 3D geometric model of the target component is constructed; based on key parameters such as the curvature radius of the building facade, bending arc length, and profile wall thickness, a bending capacity simulation evaluation is conducted to identify potential processing difficulties and generate a bending process simulation model to guide production.

[0022] S2. Simplification and Storage of Profile Diagrams: The profile cross-section diagrams required for bending are optimized and simplified. Rounded corners that affect the model's calculation efficiency and the success rate of Boolean operations are converted into right angles. Duplicate line segments are deleted, and broken lines are corrected to ensure that the cross-section is closed. A one-to-one correspondence is established between the optimized profile cross-section, its spatial reference point, and unique number information through a dedicated plugin (such as Kettybin), and stored in a central database for later retrieval.

[0023] S3. Template Design: Based on the bending process simulation model generated in S1, extract the geometric features of the component, such as bending radius, torsion angle, and rate of curvature change, and design a matching physical template (e.g., ...). Figure 2 (The diagram shows a contouring of the template). The template system includes an iron plate template for main forming support and a wooden template for auxiliary positioning and detection. The iron plate template is processed by a roller mill according to the radius of the drawing and reduced by a preset ratio (such as 90%) and then springback is calculated. The wooden template is made by a carving machine after the radius and angle are reduced by a preset ratio, and then stacked and fixed according to the number to meet the spatial shape requirements.

[0024] S4. Filler Section Processing and Mold Installation: Based on the cross-sectional shape and cavity structure of the profile, the filler is designed and processed, usually PE (polyethylene) sheet / strip or PP (polypropylene) sheet / strip. For complex cavities, stainless steel auxiliary strips can be used to enhance support. The dimensions of the filler are processed with a negative tolerance of 0.5-1mm to ensure that it can be smoothly filled and closely fit the inner wall of the profile. Subsequently, specially designed iron clamp molds are installed at both ends of the profile and fixed stably by bolts or buckle mechanisms to provide reliable clamping points for the bending machine.

[0025] S5. Bending Forming Control: The CNC bending machine is used to form the profile with the mold installed. The clamping force at both ends of the profile and the tensile force applied in the middle section are precisely controlled. The ratio of clamping force to tensile force is preset according to the material type, cross-sectional shape and bending radius through calibration parameters. In order to compensate for material springback, the target radius is reduced when setting the bending path. The reduction ratio is automatically calculated according to the target radius: when the radius is ≤1000mm, the reduction is about 7%; when the radius is about 5000mm, the reduction is about 12%; and when the radius is ≥10000mm, the reduction is about 15%, to ensure that the actual curvature after unloading and springback meets the design requirements.

[0026] S6. Reverse Scanning and Correction: Immediately after bending, a 3D scanner is used to scan the workpiece from all angles, generating a high-precision STL surface model file. This scanned model is then automatically compared with the original STEP format 3D model provided during the design phase, generating a result such as... Figure 4The report provides an intuitive color-coded deviation analysis. For areas where the deviation exceeds the ±1.5mm tolerance range, local correction is performed: minor deviations are fine-tuned using a manual hydraulic device in conjunction with PP boards, angle irons, and other tooling. For overall or large-scale shape deviations, a computer-controlled shaping machine or a three-dimensional straightening machine is used for precise mechanical correction until the hyperbolic shape accuracy of the profile meets the tolerance requirements.

[0027] in, Figure 4 This is a schematic diagram of deviation analysis generated from 3D scanning comparison. The deviation values ​​shown in the diagram (such as +0.68, -0.23, +1.25, +0.51, etc.) and the legend markings represent the detection results of a certain engineering example. Different deviation values ​​in the diagram are displayed in different colors, which can intuitively show the deviation range. It is used to demonstrate the distribution of positive and negative deviation areas and the method of judging out-of-tolerance.

[0028] S7. Three-dimensional correction and contour testing: The preliminarily corrected profile is placed in a specially designed three-dimensional contour testing fixture (such as...). Figure 3 As shown, the fixture base adopts a standardized and modular design, which can be adjusted by adjusting the bolt spacing (e.g., one spacing every 200mm) to adapt to different specifications of profiles (especially ribbed profiles). During inspection, the focus is on checking the fit between the profile sidewall and the fixture and the flatness of the bottom surface, controlling the fit error to within 2mm. When the inspection system finds that the deviation exceeds the set threshold, it automatically prompts the operator to recalibrate. For profiles with torsional deviations, a three-dimensional calibration machine can be used for rotational torsional adjustment to bring them back to the correct spatial posture.

[0029] in, Figure 3 This is a schematic diagram of the profilometry testing fixture. The dimension markings (such as 1400) and node numbers (such as 07140-003-01, 07140-003-02, 07140-004-01, 07140-004-02, etc.) shown in the diagram are schematic identifiers of the specific engineering profile corresponding to the fixture (UN140), used to illustrate the fit and testing position of the profile's side and bottom surface with the fixture (UN140) and the testing principle.

[0030] S8. Aging and Hardness Treatment: Heat treatment is performed on profiles that have passed the shape accuracy inspection to improve their mechanical properties. The profiles are placed in an aging furnace, heated to 180°C-200°C and held for 4 hours. Then the furnace door is opened to allow the workpiece to cool to room temperature in a natural environment. This process can increase the hardness of the bending material (such as 6063-T4) to T6. After treatment, a hardness tester is used to test the hardness at at least three points on the end, middle and apex of the profile to ensure that the hardness value meets the requirement of ≥12HB (Webster hardness).

[0031] S9. Surface Treatment and Protection: Perform surface finishing on the heat-treated profiles; use a pneumatic grinder with 60-grit, 120-grit, and 320-grit sandpaper for graded grinding and polishing to eliminate surface defects and achieve the required smoothness; conduct paint spraying tests on 20% of key profiles (such as corrugated and transverse profiles) to review and confirm coating quality; after processing, the profiles... Figure 5 As shown; finally, apply special high-temperature resistant white protective tape to the exposed surface of the profile to prevent scratches in subsequent processes, and affix labels containing number and specification information according to project requirements.

[0032] S10. Data Traceability and Digital Closed Loop: Key data generated throughout the entire process, including BIM design models, processing parameters (tension and bending force, temperature, time, etc.), 3D scanning reports, aging furnace temperature control curves, hardness test results, and quality inspection records, are linked through a unique profile ID and uploaded to a cloud-based process management platform. This platform integrates three types of interfaces: design, production, and testing, to achieve digital closed-loop management and full-process quality traceability from design, manufacturing, testing to feedback optimization.

[0033] Example: This example uses the bending process of hyperbolic aluminum profiles used in the hyperbolic unitized curtain wall of a large commercial building.

[0034] Preparations before implementation: Confirm that the profile material is 6063-T4 aluminum, and the target hardness after treatment is T6 (≥12HB). Prepare hardware and software equipment such as Rhino 7.0, Grasshopper, Kettybin plugin, BIM collaboration platform, CNC bending machine, 3D scanner, aging furnace, and hardness tester.

[0035] Implementation steps: Step 1: Modeling and Evaluation The architect provides a digital model of the building's facade, and the operators use Rhino and Grasshopper for parametric detailed design, creating accurate BIM models of curtain wall units and profiles. Through Grasshopper's logic modules, the panels are automatically decomposed, boundary lines are extracted, and stored profile sections are retrieved. The system performs a bending feasibility analysis based on the profile's bending radius (e.g., a hyperbolic member with a radius of 3500mm in one direction and 12000mm in the other), wall thickness (e.g., 3mm), arc length, etc., assesses stress concentration areas, and generates a digital model containing all processing information. Each component in the model includes information such as profile module number, reference plane, stretching line, and processing number.

[0036] Step 2: Simplifying and storing the model diagram: Import the CAD drawing of the profile section from the design node into Rhino. Using Grasshopper scripts or manual operation, simplify the rounded corners of non-critical parts of the section to right angles, delete duplicate outlines, and ensure that all line segments are connected end to end to form a closed section. Then, use the Kettybin plugin to bind the simplified section to a defined reference point (such as the lower left corner of the section) and store it in the project database with a template number (such as "VMU1-HengLiao-01").

[0037] Step 3: Template Design The centerline curvature data of the target profile is extracted from the BIM model. For components that mainly bear the bending load, a steel plate template is designed. Springback compensation is calculated (e.g., for a target radius of 5000mm, a 12% reduction is applied, and the bending die radius is set to 4400mm). The data is then input into a roller mill to produce a curved steel plate mold that meets the requirements. For complex twisted parts that require inspection or auxiliary positioning, multi-layer wooden templates are designed. Based on the compensated 3D data, each layer of wooden boards is processed separately using a CNC engraving machine. These layers are then stacked in numerical order and fixed with screws to form a contour template that matches the spatial shape of the target profile.

[0038] Step 4: Filling section processing and mold assembly: Based on the profile cross-sectional cavity dimensions, a laser cutting machine is used to process the PE sheet into strips with a width slightly smaller than the cavity (negative tolerance 0.8mm). For long-span profiles, a 5mm thick stainless steel plate is sandwiched in the middle of the PE strip to increase rigidity. The filler strip is then tightly inserted into the profile cavity, ensuring full filling. Pre-machined wire-cut iron clamping molds are then installed at both ends of the profile. The clamping mold's inner cavity cross-section is 1mm smaller than the profile cross-section, and its length is approximately 150mm. These molds are then bolted to the ends of the profile.

[0039] Step 5, Bending and Forming Control: The prepared profiles are clamped onto the CNC bending machine. Process parameters are set: for 50mm x 100mm aluminum square tubes, the clamping force is set to 11 MPa, and the tension force is set to 9 MPa. The bending machine automatically performs the bending operation based on the input, springback-compensated path data (radius 4400mm). The operator monitors the pressure and displacement curves in real time to ensure process stability.

[0040] Step Six: Reverse Scanning and Correction After stretch bending is completed, unload the workpiece and place it on the scanning station, with the bottom raised by more than 10 mm. Use a 3D scanner to obtain the STL point cloud data of the whole workpiece. The scanning software automatically aligns and compares the STL data with the designed STEP model to generate a color deviation map. It is found that the arch height deviation at a certain place is +2.2 mm, exceeding the upper limit of +1.5 mm. According to the report, the operator uses a manual hydraulic jack device and cooperates with a customized angle iron tooling to perform local micro-pressure correction in this area. After correction, rescan to confirm that the deviation has been reduced to +1.0 mm, meeting the requirements.

[0041] Step 7. 3D correction and profiling detection: Lift the corrected profile to the profiling detection platform. The support screws of the platform fixture have been pre-adjusted to the corresponding positions according to the profile number. Slowly lower the profile so that its side and bottom surfaces contact the profiling blocks of the fixture. Use a feeler gauge to check the fitting gap and find that there is a side gap of 2.5 mm in the middle. The system gives an alarm prompt. The operator activates the 3D correction machine, holds this section of the profile, and performs a small amount of rotational twisting operation until, when detected again, the fitting gap at all inspection points is less than 2 mm.

[0042] Step 8. Aging and hardness treatment: Transfer the qualified profiles to the aging furnace area, fix them with a special frame to prevent shaking caused by the hot air circulation in the furnace. Close the furnace door, set the furnace temperature to 190 °C, start heating and keep it warm for 4 hours. After the time is up, cool it naturally to room temperature. After taking it out, the quality inspection personnel use a hardness tester to measure the hardness at both ends and the middle of the arc top of the profile. The readings are 13 HB, 13 HB, and 14 HB respectively, with an average value of 13.3 HB, meeting the requirement of ≥12 HB.

[0043] Step 9. Surface treatment and protection: Grind the visible surface of the profile. First, use 60-mesh sandpaper to remove slight stretch bending marks, then use 120-mesh sandpaper to refine it, and finally use 320-mesh sandpaper for fine polishing. Randomly select 20% of the profiles from this batch for a fluorocarbon spraying test. After quality inspection and review, confirm that the paint adhesion and color are qualified. Finally, paste the specified white protective adhesive paper on the visible surface of all profiles and attach a QR code label containing the profile ID, length, and unit number.

[0044] Step 10. Data traceability and digital closed-loop: All key data from the above steps, such as the processing drawings generated by Grasshopper, the process parameter logs of the bending machine, the 3D scanning report, the temperature control records of the aging furnace, hardness test values, and the paint test report, are automatically or manually uploaded to the enterprise cloud platform by scanning QR code labels. The platform associates this data with the initial BIM design model to form a complete digital twin. Managers can use the platform to monitor production progress and quality status in real time, achieving full-chain digital closed-loop management from virtual design to physical manufacturing.

[0045] Through the above implementation process, the present invention successfully produced high-precision hyperbolic curtain wall profiles for a large commercial building, proving the feasibility and superiority of the process.

[0046] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A hyperbolic bending process, characterized in that, Includes the following steps: S1. Modeling and Evaluation Stage: Using the 3D modeling software Rhino and its parametric plugin Grasshopper, combined with the BIM system, a 3D geometric model of the target component is constructed. Based on parameters such as the curvature radius of the building facade, bending arc length, and profile thickness, the flexibility is evaluated, and a bending process simulation model is generated. S2. Simplification and storage of template: The cross-section of the bending template is optimized, the rounded corners that affect the accuracy are converted into right angles, duplicate line segments are deleted and the fault line segments are corrected. Then, the profile cross-section and its reference points and numbers are stored in the database one by one through the plug-in. S3. Template Design: Based on the bending radius, torsion angle, and curvature change rate set in the model, design the corresponding template and process the bending template. S4. Filling section processing and mold installation: Fill with PE / PP board or stainless steel auxiliary strip according to the profile cross-section design, fill according to the negative tolerance of 0.5-1mm, install iron clamp mold and fix it stably with bolts or buckles; S5. Bending and forming control: The two ends of the profile are clamped by a CNC bending machine, and a controllable tension is applied to the middle section. The ratio of clamping force to tension is set according to the calibration parameters, and the radius is reduced by 7-15% according to the required curvature to compensate for springback. S6. Reverse scanning and correction: After bending, the formed part is scanned and modeled using a 3D scanner to generate a comparison report with the design model. For areas where the deviation exceeds ±1.5mm, local mechanical or manual adjustment is performed. S7. Three-dimensional correction and contour testing: Place the corrected profile on the three-dimensional contour testing fixture, test the fit of the sides and bottom, control the fit error to within 2mm, and use the three-dimensional correction machine to rotate and twist to adjust when there is a deviation. S8. Aging and Hardness Treatment: High-temperature aging treatment is carried out on qualified profiles at 180°C-200°C. After holding at the temperature for 4 hours, the profiles are naturally cooled and the hardness is tested to reach ≥12HB. S9. Surface treatment and protection: After manual grinding, painting test and surface inspection of the formed profiles, implement anti-scratch tape protection and double packaging in accordance with project requirements. S10, Data Traceability and Digital Closed Loop: The 3D geometric model and bending process simulation model data generated by S1, the processing parameters such as the clamping force to tension ratio and springback compensation reduction ratio set in S5, the 3D scanning comparison report generated by S6, and the quality inspection records such as the conformal testing fit record in S7, the aging hardness test record in S8, and the painting test record in S9 are uploaded to the cloud process platform. Through the association of unique profile IDs, a digital closed-loop management is realized from design, manufacturing, testing to feedback. In the bending forming control process, the reduction ratio of the bending radius is automatically calculated according to the change of the target radius: 7% when the radius is ≤1000mm, 12% when the radius is 5000mm, and 15% when the radius is above 10000mm, in order to compensate for material springback and ensure curvature accuracy.

2. The hyperbolic bending process according to claim 1, characterized in that: During the modeling and evaluation phase, the Grasshopper program uses logical battery connections to achieve panel decomposition, node extraction, and parametric control, so that the node information of each component includes profile template number, reference plane, stretching line, and processing number, thereby realizing one-click batch drawing output and data-driven modeling.

3. The hyperbolic bending process according to claim 1, characterized in that: The bending template in the template design includes an iron plate template and a wooden template. The iron plate template is made by a roller mill that reduces the radius of the drawing by 90% and then rebounds. The wooden template is made by a carving machine that reduces the radius and angle proportionally, and then stacks and fixes them according to the numbering.

4. The hyperbolic bending process according to claim 1, characterized in that: In the reverse scanning and correction steps, a three-dimensional scanning detection system is used to create an STL surface file and compare it with the STEP file provided by the design. The deviation results generate a color deviation map. The out-of-tolerance parts are locally adjusted to within the tolerance of ±1.5mm by a manual hydraulic device or a computer-controlled shaping machine. For overall shape deviations, a shaping machine or a three-dimensional correction machine is used for mechanical correction to ensure that the hyperbolic shape accuracy of the profile meets the tolerance requirements.

5. The hyperbolic bending process according to claim 1, characterized in that: During 3D calibration and contour testing, the fixture base adopts a standardized modular design, which can adapt to different specifications of materials by adjusting the bolt spacing. During the testing process, the fit of the side wall and the flatness of the bottom surface are mainly checked. If the deviation exceeds 2mm, the fixture will automatically prompt for recalibration.

6. The hyperbolic bending process according to claim 1, characterized in that: Before the aging and hardening treatment, the bending parts need to be spatially positioned using a special fixed frame to prevent the material from undergoing secondary deformation due to hot air disturbance; after the treatment, a hardness meter is used to test the hardness at three points: the end, middle and apex of the profile, and the average value is calculated.

7. The hyperbolic bending process according to claim 1, characterized in that: During the surface treatment and protection process, the grinding is carried out by using a pneumatic grinder with 60, 120 and 320 grit sandpaper for graded grinding; 20% of the painted samples are randomly inspected; the exposed surfaces are covered with special high-temperature resistant white protective tape and labeled with numbers according to project requirements.

8. The hyperbolic bending process according to claim 1, characterized in that: In the aforementioned data traceability and digital closed loop, the cloud-based process platform includes three types of interfaces: design, production, and testing. Its information synchronization structure includes: Design parameters, processing logs, 3D inspection reports, aging furnace temperature records and hardness test results are recorded, and the entire process is traceable through a unique profile ID.

9. The hyperbolic bending process according to claim 1, characterized in that: The process is applicable to the bending and forming of single-curved, double-curved, and irregularly shaped twisted profiles. It can be widely used in the production of irregularly shaped building structural components such as double-curved unitized curtain walls, arched sunroofs, and three-dimensional decorative components, realizing mass production, high precision, and traceable digital manufacturing.

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