Method for on-line monitoring and compensation control of dimensional accuracy of aluminum profile extrusion process

Abstract

The application discloses a size precision online monitoring and compensation control method for an aluminum profile extrusion process and belongs to the technical field of aluminum profile production. The method comprises the following steps: acquiring real-time section data of hot aluminum profiles, wherein the real-time section data comprises hot section point cloud data, hot characteristic size data and section temperature field data; determining a cold section geometric model according to the real-time section data; determining size deviation data according to the cold section geometric model and a preset design model; and generating double-stage compensation control instructions according to the size deviation data, wherein the double-stage compensation control instructions comprise a first-stage macroscopic control instruction and a second-stage microscopic control instruction, the first-stage macroscopic control instruction is used for regulating and controlling an extrusion speed and a partition cooling air pressure, and the second-stage microscopic control instruction is used for controlling a die elastic compensation layer, so that the beneficial effect of improving production quality is achieved.

Description

Technical Field

[0001] This invention relates to the field of aluminum profile manufacturing technology, and in particular to a method for online monitoring and compensation control of dimensional accuracy during the aluminum profile extrusion process. Background Technology

[0002] In the aluminum profile extrusion process, the profile undergoes rapid cooling and shrinkage after exiting the die, resulting in a significant difference between its final geometric dimensions and the die opening dimensions at high temperature. Current quality control methods primarily rely on offline sampling inspection, where samples are taken from the end of the profile after it has fully cooled, and measured manually using a coordinate measuring machine or specialized gauges. This method has a low inspection frequency and lags significantly behind the production cycle, making it impossible to promptly detect die opening anomalies and implement closed-loop correction. While some production lines have introduced online measurement devices, the inspection points are typically located at the end of the cooling section or after the traction machine, far from the die opening. The measurement results reflect the cross-sectional dimensions after cooling, by which time the profile has already shrunk and solidified. The control loop cannot effectively provide feedback on the die exit status, thus hindering real-time die compensation in continuous production and leading to a decline in production quality.

[0003] The above content is only used to help understand the technical solution of the present invention and does not represent an admission that the above content is prior art. Summary of the Invention

[0004] The main objective of this invention is to provide an online monitoring and compensation control method for the dimensional accuracy of aluminum profiles during the extrusion process, aiming to improve production quality. To achieve the above objective, this invention provides a method for online monitoring and compensation control of the dimensional accuracy of aluminum profiles during the extrusion process, comprising the following steps: Real-time cross-sectional data of hot aluminum profiles are obtained, including: hot cross-sectional point cloud data, hot characteristic dimension data, and cross-sectional temperature field data; The cold-state cross-section geometric model is determined based on the real-time cross-section data; The dimensional deviation data are determined based on the cold-state cross-sectional geometric model and the preset design model; Based on the dimensional deviation data, a two-stage compensation control instruction is generated. The two-stage compensation control instruction includes a first-stage macro control instruction and a second-stage micro control instruction. The first-stage macro control instruction is used to regulate the extrusion speed and the zoned cooling air pressure, and the second-stage micro control instruction is used to control the mold elastic compensation layer.

[0005] Optionally, the step of determining the cold cross-section geometric model based on the real-time cross-section data includes: Obtain the preset material dynamic thermal shrinkage matrix; Based on the cross-sectional temperature field data and the material dynamic thermal shrinkage matrix, nonlinear reverse shrinkage calculations are performed on the hot cross-sectional point cloud data and the hot characteristic size data to obtain the cold cross-sectional geometric model.

[0006] Optionally, the step of determining the dimensional deviation data based on the cold-state cross-sectional geometric model and the preset design model includes: Align the cold-state cross-section geometric model with the preset design model in spatial coordinate system; Boolean difference operation is performed on the aligned cold cross-section geometric model and the preset design model to generate the full cross-section error matrix; The dimensional deviation data is determined based on the full cross-section error matrix, and the dimensional deviation data includes: local maximum dimensional deviation and overall deformation trend.

[0007] Optionally, the step of generating a two-order compensation control command based on the dimensional deviation data includes: When the overall deformation trend exceeds the preset deformation threshold, the first-order macroscopic control command is generated. When the local maximum size deviation exceeds the preset tolerance threshold, the second-order micro-control command is generated.

[0008] Optionally, the step of generating the first-order macroscopic control command when the overall deformation trend exceeds a preset deformation threshold includes: When the overall deformation trend is that the overall wall thickness is thinner or thicker in the same direction, a first speed adjustment command is generated to reduce or increase the extruder main plunger advance speed. When the overall deformation trend is overall bending or asymmetrical twisting, a first wind pressure adjustment command and a stretching straightening rate adjustment command are generated. The first wind pressure adjustment command is used to increase the wind pressure of the zoned cooling fan on the thinned side or the inner bending side, and the stretching straightening rate adjustment command is used to adjust the online stretching straightening rate towards the upper limit of the fitting.

[0009] Optionally, the step of generating the second-order micro-control command when the local maximum dimensional deviation exceeds a preset tolerance threshold includes: Calculate the target spatial coordinates of the local maximum dimensional deviation on the profile cross-section; When the local maximum dimensional deviation is a local wall thickness deviation or hole position offset, an elongation drive signal is output to the piezoelectric ceramic actuator corresponding to the target spatial coordinates to increase the frictional resistance of the working zone at that location. When the local maximum dimensional deviation is the cantilever size gradually opening or closing, a pressure adjustment signal is output to the micro high-pressure hydraulic chamber corresponding to the target spatial coordinates to apply reverse prestress to the mold cantilever.

[0010] Optionally, the first-order macroscopic control command and the second-order microscopic control command are executed decoupled. When the local maximum dimensional deviation exceeds a preset tolerance threshold and the overall deformation trend does not exceed a preset deformation threshold, only the second-order microscopic control command is executed, and the first-order macroscopic control command remains in its current state. When the overall deformation trend exceeds a preset deformation threshold and the local maximum dimensional deviation does not exceed a preset tolerance threshold, only the first-order macroscopic control command is executed, and the second-order microscopic control command remains in its current state.

[0011] Furthermore, to achieve the above objectives, the present invention also provides an online monitoring and compensation control device for the dimensional accuracy of aluminum profile extrusion processes, the online monitoring and compensation control device for the dimensional accuracy of aluminum profile extrusion processes comprising: The acquisition module is used to acquire real-time cross-sectional data of hot aluminum profiles. The real-time cross-sectional data includes: hot cross-sectional point cloud data, hot characteristic dimension data, and cross-sectional temperature field data. The modeling module is used to determine the cold cross-section geometric model based on the real-time cross-section data; The analysis module is used to determine dimensional deviation data based on the cold-state cross-sectional geometric model and the preset design model; The control module is used to generate two-stage compensation control instructions based on the dimensional deviation data. The two-stage compensation control instructions include: a first-stage macro control instruction and a second-stage micro control instruction. The first-stage macro control instruction is used to regulate the extrusion speed and the zoned cooling air pressure, and the second-stage micro control instruction is used to control the mold elastic compensation layer.

[0012] Furthermore, to achieve the above objectives, the present invention also provides an online monitoring and compensation control device for the dimensional accuracy of an aluminum profile extrusion process. The online monitoring and compensation control device for the dimensional accuracy of an aluminum profile extrusion process includes: a memory, a processor, and an online monitoring and compensation control program for the dimensional accuracy of an aluminum profile extrusion process stored in the memory and executable on the processor. The online monitoring and compensation control program for the dimensional accuracy of an aluminum profile extrusion process is configured to implement the steps of the online monitoring and compensation control method for the dimensional accuracy of an aluminum profile extrusion process as described above.

[0013] Furthermore, to achieve the above objectives, the present invention also provides a storage medium storing an online monitoring and compensation control program for the dimensional accuracy of an aluminum profile extrusion process. When the online monitoring and compensation control program for the dimensional accuracy of an aluminum profile extrusion process is executed by a processor, it implements the steps of the online monitoring and compensation control method for the dimensional accuracy of an aluminum profile extrusion process described in any of the above claims.

[0014] This invention proposes an online monitoring and compensation control method for dimensional accuracy in the aluminum profile extrusion process. The method acquires real-time cross-sectional data of the hot aluminum profile, determines the cold cross-sectional geometric model based on the real-time cross-sectional data, determines dimensional deviation data based on the cold cross-sectional geometric model and a preset design model, and generates a two-stage compensation control command based on the dimensional deviation data, thereby achieving high-precision extrusion compensation and improving the quality of the aluminum material. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of the online monitoring and compensation control device for the dimensional accuracy of aluminum profile extrusion process in the hardware operating environment involved in the embodiments of the present invention; Figure 2 This is a flowchart illustrating the first embodiment of the online monitoring and compensation control method for dimensional accuracy in the aluminum profile extrusion process of the present invention. Figure 3 This is a flowchart illustrating the second embodiment of the online monitoring and compensation control method for dimensional accuracy in the aluminum profile extrusion process of the present invention.

[0016] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0017] It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0018] Reference Figure 1 , Figure 1 This is a schematic diagram of the structure of an online monitoring and compensation control device for the dimensional accuracy of aluminum profile extrusion process in the hardware operating environment involved in the embodiments of the present invention.

[0019] like Figure 1As shown, the online monitoring and compensation control device for the dimensional accuracy of the aluminum profile extrusion process may include: a processor 1001, such as a central processing unit (CPU), a communication bus 1002, an interactive device 1003, a network interface 1004, and a memory 1005. The communication bus 1002 is used to enable communication between these components. The interactive device 1003 may include a display screen or an input unit such as a keyboard. Optionally, the interactive device 1003 may also be connected to the communication bus via standard wired or wireless interfaces. The network interface 1004 may optionally include standard wired or wireless interfaces (such as a Wi-Fi interface). The memory 1005 may be a high-speed random access memory (RAM) or a stable non-volatile memory (NVM), such as a disk drive. Optionally, the memory 1005 may also be a storage device independent of the aforementioned processor 1001. Optionally, the online monitoring and compensation control equipment for the dimensional accuracy of the aluminum profile extrusion process can be a device for controlling the operation of the production line.

[0020] Those skilled in the art will understand that Figure 1 The structure shown does not constitute a limitation on the online monitoring and compensation control equipment for dimensional accuracy of aluminum profile extrusion process. It may include more or fewer components than shown, or combine certain components, or have different component arrangements.

[0021] like Figure 1 As shown, the memory 1005, which serves as a storage medium, may include an operating system, a data storage module, a network communication module, a user interface module, and an online monitoring and compensation control program for the dimensional accuracy of the aluminum profile extrusion process.

[0022] exist Figure 1 In the online monitoring and compensation control device for the dimensional accuracy of the aluminum profile extrusion process shown, the network interface 1004 is mainly used for data communication with other devices; the interactive device 1003 is mainly used for data interaction with the user; the processor 1001 and memory 1005 in the online monitoring and compensation control device for the dimensional accuracy of the aluminum profile extrusion process of the present invention can be set in the online monitoring and compensation control device for the dimensional accuracy of the aluminum profile extrusion process. The online monitoring and compensation control device for the dimensional accuracy of the aluminum profile extrusion process calls the online monitoring and compensation control program for the dimensional accuracy of the aluminum profile extrusion process stored in the memory 1005 through the processor 1001, and executes the online monitoring and compensation control method for the dimensional accuracy of the aluminum profile extrusion process provided in the embodiment of the present invention.

[0023] This invention provides a method for online monitoring and compensation control of dimensional accuracy in aluminum profile extrusion processes, applied to an aluminum profile extrusion production line. The production line, arranged from top to bottom along the extrusion direction, includes an extrusion main unit, a die sensor array, a traction machine with zoned cooling, an online tension straightener, and a die elastic compensation layer integrated inside the extrusion die base. The main controller connects to each actuator and sensor via an industrial bus and is responsible for running the control algorithm. The sensor array is deployed at the front end of the cooling traction zone, 0.5 to 1.5 meters from the die exit, and includes two sets of orthogonally deployed high-frequency line laser scanners, a laser ranging array aligned with the hollow holes and the inner side of the open cantilever of the profile, and a multi-point infrared thermometer to acquire the instantaneous temperature at different wall thicknesses of the cross-section. The die elastic compensation layer comprises an array of piezoelectric ceramic actuators and a micro-high-pressure hydraulic chamber array distributed around the working zone of the profile cross-section, capable of generating axial displacement from 0 to 100 micrometers. (Refer to...) Figure 2 , Figure 2 This is a flowchart illustrating the first embodiment of the online monitoring and compensation control method for dimensional accuracy in the aluminum profile extrusion process of the present invention.

[0024] In this embodiment, the online monitoring and compensation control method for dimensional accuracy during the aluminum profile extrusion process includes: Step S1: Obtain real-time cross-sectional data of the hot aluminum profile. The real-time cross-sectional data includes: hot cross-sectional point cloud data, hot characteristic dimension data, and cross-sectional temperature field data. In this embodiment, a line laser scanner, a laser ranging array, and an infrared thermometer capture real-time point cloud data and key feature dimensions of the aluminum profile in its hot state across the entire cross-section, such as hole positions, wall thickness, and cross-sectional temperature field data, at a synchronous frequency greater than or equal to 50 Hz. Since the detection point is only 0.5 to 1.5 meters away from the die opening, data acquisition can be completed before the profile enters the cooling traction zone, and the total closed-loop response time of the control loop is controlled within 50 milliseconds.

[0025] Step S2: Determine the cold cross-section geometric model based on the real-time cross-section data; In this embodiment, the main controller calls the built-in material dynamic thermal shrinkage matrix to perform nonlinear reverse shrinkage calculations on the hot point cloud data and hot feature size data based on the cross-sectional temperature field data, and deduce the corresponding room temperature cold state full cross-section geometric model.

[0026] Step S3: Determine the dimensional deviation data based on the cold-state cross-section geometric model and the preset design model; In this embodiment, the cold-state cross-section geometric model is aligned with the preset initial design CAD model by best fitting in the spatial three-coordinate system, the full cross-section Boolean difference operation is performed to generate the error matrix of the full feature dimensions, and the local maximum size deviation and the overall deformation trend are extracted.

[0027] Step S4: Generate a two-stage compensation control instruction based on the dimensional deviation data. The two-stage compensation control instruction includes a first-stage macro control instruction and a second-stage micro control instruction. The first-stage macro control instruction is used to regulate the extrusion speed and the zoned cooling air pressure. The second-stage micro control instruction is used to control the mold elastic compensation layer.

[0028] In this embodiment, by acquiring real-time cross-sectional data of hot aluminum profiles, determining a cold cross-sectional geometric model based on the real-time cross-sectional data, determining dimensional deviation data based on the cold cross-sectional geometric model and a preset design model, and generating a two-stage compensation control command based on the dimensional deviation data, high-precision extrusion compensation can be achieved, thereby improving the quality of aluminum materials.

[0029] Furthermore, based on the first embodiment, a second embodiment of the present invention is proposed, which provides an online monitoring and compensation control method for dimensional accuracy in the aluminum profile extrusion process. In this embodiment, reference is made to... Figure 3 The step of determining the cold cross-section geometric model based on the real-time cross-section data includes: Step S21: Obtain the preset material dynamic thermal shrinkage matrix; In this embodiment, the material dynamic thermal shrinkage matrix is ​​pre-stored in the main controller or digital twin platform. This matrix describes the nonlinear shrinkage characteristics of different aluminum alloy materials under different temperature gradients, taking into account the differences in shrinkage rate caused by uneven wall thickness. The matrix construction process is as follows: For the target aluminum alloy grade, standard samples are prepared in a laboratory environment with different cross-sectional wall thicknesses, typically 5 to 8 typical wall thicknesses ranging from 1 mm to 10 mm. The samples are cooled stepwise from the die temperature, typically 450 to 550 degrees Celsius, to room temperature using a controlled-temperature chamber. The change in sample length is precisely measured at each temperature step, and the shrinkage rate of each wall thickness at each temperature point is recorded. The measured data are fitted into a three-dimensional nonlinear functional relationship between wall thickness, temperature, and shrinkage rate, and stored as the material dynamic thermal shrinkage matrix in the form of a two-dimensional lookup table or analytical function. The row index of the matrix represents the temperature gradient range, such as 450 to 400 degrees Celsius, 400 to 350 degrees Celsius, and up to 50 to 25 degrees Celsius. The column index represents the wall thickness level, and the matrix elements represent the shrinkage coefficient under the corresponding conditions.

[0030] Step S22: Based on the cross-sectional temperature field data and the material dynamic thermal shrinkage matrix, perform nonlinear reverse shrinkage calculation on the hot cross-sectional point cloud data and the hot characteristic size data to obtain the cold cross-sectional geometric model.

[0031] In this embodiment, the nonlinear reverse shrinkage calculation process is as follows: First, the hot cross-sectional point cloud data is divided into regions. Based on the three-dimensional coordinates and wall thickness information of each point in the point cloud data, the cross-section is divided into several wall thickness segments, such as thin-walled, medium-walled, and thick-walled regions. Second, the cross-sectional temperature field data is spatially mapped. Using the multi-point temperature values ​​obtained by the infrared thermometer, bilinear interpolation or thin-plate spline interpolation is used to assign a corresponding instantaneous temperature value to each data point in the point cloud. Then, the reverse shrinkage iterative calculation is performed point by point: starting from the hot temperature, the temperature decreases towards room temperature according to a preset temperature step size. At each temperature step, the material dynamic thermal shrinkage matrix is ​​queried to obtain the shrinkage coefficient corresponding to the current wall thickness and current temperature gradient at that point. The preset temperature step size can be 10 degrees Celsius. The coordinate value of the point is reduced proportionally along the shrinkage direction, and the feature size is reduced by the same shrinkage coefficient. Since the shrinkage coefficient changes nonlinearly with temperature and wall thickness, the shrinkage amount at each point is different. Therefore, the shrinkage rate of the thin-walled region and the thick-walled region are different, and it needs to be iterated separately until all points reach room temperature. During the iteration process, when the temperature at a certain point drops to room temperature, the shrinkage calculation stops at that point, marking it as a converged state. It should be noted that room temperature here generally refers to 25 degrees Celsius. The iteration ends when all points are marked as converged. Finally, the converged point cloud data undergoes boundary smoothing to eliminate numerical noise generated during the iteration process, resulting in a cold-state cross-sectional geometric model under room temperature conditions. This model accurately reflects the final solidified geometry of the profile after cooling, with shrinkage differences in different wall thickness regions accurately compensated for.

[0032] Furthermore, based on the first or second embodiment, a third embodiment of the present invention is proposed for an online monitoring and compensation control method for dimensional accuracy in the aluminum profile extrusion process. In this embodiment, the step of determining the dimensional deviation data based on the cold-state cross-section geometric model and the preset design model includes: Align the cold-state cross-section geometric model with the preset design model in spatial coordinate system; Boolean difference operation is performed on the aligned cold cross-section geometric model and the preset design model to generate the full cross-section error matrix; The dimensional deviation data is determined based on the full cross-section error matrix, and the dimensional deviation data includes: local maximum dimensional deviation and overall deformation trend.

[0033] In this embodiment, the preset design model is the initial design CAD model of the profile. The alignment process adopts the best fitting method of the three-coordinate system in space, specifically: select three or more non-collinear feature reference points on the cold-state cross-section geometric model, and find the corresponding theoretical reference points on the CAD model. These theoretical reference points can generally be: outer contour corner points, hole center points, etc. The rigid body transformation matrix between the two point sets is calculated by the least squares method, i.e., translation and rotation, to transform the cold-state model to a coordinate system unified with the CAD model, so as to minimize the root mean square deviation between the two.

[0034] Furthermore, in this embodiment, the Boolean difference operation can be specifically performed as follows: Under the aligned unified coordinate system, the cold-state cross-sectional geometric model is taken as the measured entity A, and the CAD design model is taken as the theoretical entity B, and the spatial difference between A and B is calculated. The operation process consists of three sub-steps: First, meshing processing, discretizing the two entity models into equally spaced three-dimensional voxel meshes or triangular facet meshes to ensure that the mesh resolution meets the dimensional accuracy detection requirements, which are typically 0.01mm to 0.05mm; Second, point-by-point difference calculation, at each mesh node or facet center point of the model, calculating the directed distance from the surface of the measured entity A to the surface of the theoretical entity B. If the surface of A is located outside the surface of B, i.e., the wall thickness is too large, the distance value is positive; if the surface of A is located inside the surface of B, i.e., the wall thickness is too small, the distance value is negative; Third, error matrix assembly, arranging the directed distance values ​​of all mesh points according to spatial coordinates to form a full-section error matrix. Each element in the error matrix records the dimensional deviation value at the corresponding spatial location, along with information on the direction of deviation, typically positive or negative. This is further transformed into a three-dimensional error cloud map, visually presenting the dimensional deviation distribution across different regions of the cross-section, facilitating operators' intuitive identification of the location and severity of out-of-tolerance areas. Further, the process of extracting two key indicators from the full-section error matrix involves: for the local maximum dimensional deviation, scanning element-by-element in the full-section error matrix and selecting the element with the largest absolute value as the local maximum dimensional deviation, while simultaneously recording the corresponding spatial coordinates for target positioning during subsequent second-order micro-compensation; for the overall deformation trend, principal component analysis is used to extract features from the full-section error matrix, calculating the first and second moments of the error distribution. The first moment is the mean vector, and the second moment is the covariance matrix. The mean vector reflects the overall systematic offset direction of the cross-section, such as thinning or thickening in the same direction. The eigenvector corresponding to the largest eigenvalue of the covariance matrix reflects the main direction of change in the error distribution, such as bending or twisting. The direction of the mean vector and the main eigenvalue direction of the covariance matrix are combined and encoded into the overall deformation trend, used to determine the systematic deformation mode of the profile. If all components of the mean vector have the same sign and similar values, it is determined to be either too thin or too thick in the same direction; if the mean vector shows opposite signs on both sides of the cross section, it is determined to be bending or asymmetrical twisting; if the eigenvalues ​​of the covariance matrix are evenly distributed without a clear main direction, it is determined to be random fluctuation rather than systematic deformation.

[0035] Furthermore, based on any of the above embodiments, a fourth embodiment of the present invention for an online monitoring and compensation control method for dimensional accuracy in an aluminum profile extrusion process is proposed, wherein the step of generating a two-stage compensation control command based on the dimensional deviation data includes: When the overall deformation trend exceeds the preset deformation threshold, the first-order macroscopic control command is generated. When the local maximum size deviation exceeds the preset tolerance threshold, the second-order micro-control command is generated.

[0036] In this embodiment, the preset deformation threshold is set according to the product tolerance requirements. When the overall deformation trend exceeds this threshold, it indicates that the profile has systematic deformation, and overall correction needs to be performed by adjusting the process parameters. In this embodiment, the preset tolerance threshold is set according to the product wall thickness tolerance requirements. When the maximum local dimensional deviation exceeds this threshold, it indicates that there is a local area of ​​dimensional deviation, and microscopic correction needs to be performed through the mold elastic compensation layer.

[0037] Furthermore, the step of generating the first-order macroscopic control command when the overall deformation trend exceeds the preset deformation threshold includes: When the overall deformation trend is that the overall wall thickness is thinner or thicker in the same direction, a first speed adjustment command is generated to reduce or increase the extruder main plunger advance speed. When the overall deformation trend is overall bending or asymmetrical twisting, a first wind pressure adjustment command and a stretching straightening rate adjustment command are generated. The first wind pressure adjustment command is used to increase the wind pressure of the zoned cooling fan on the thinned side or the inner bending side, and the stretching straightening rate adjustment command is used to adjust the online stretching straightening rate towards the upper limit of the fitting.

[0038] In this embodiment, an overall thinner wall thickness in the same direction indicates insufficient metal filling pressure within the die or a mismatch between the extrusion speed and the material supply. In this case, an instruction to reduce the main plunger advance speed of the extruder is generated. Conversely, an overall thicker wall thickness in the same direction generates an instruction to increase the advance speed. This adjustment is a macroscopic, common adjustment that affects the wall thickness distribution of the entire profile. Overall bending or asymmetrical twisting indicates uneven cooling on both sides of the cross-section, resulting in asymmetrical residual thermal stress. In this case, the air pressure of the zoned cooling fans on the thinned side or the inner bending side is increased to balance the cooling on both sides. Simultaneously, the online stretching straightening rate is adjusted towards the upper limit of 1.2% to eliminate residual stress. If it is below 0.5%, residual stress cannot be effectively eliminated; if it is above 1.2%, it will lead to work hardening of the aluminum material and secondary necking shrinkage of the cross-section. Therefore, the stretching straightening rate is precisely limited to the range of 0.5% to 1.2%.

[0039] Furthermore, the step of generating the second-order microscopic control command when the local maximum dimensional deviation exceeds a preset tolerance threshold includes: Calculate the target spatial coordinates of the local maximum dimensional deviation on the profile cross-section; When the local maximum dimensional deviation is a local wall thickness deviation or hole position offset, an elongation drive signal is output to the piezoelectric ceramic actuator corresponding to the target spatial coordinates to increase the frictional resistance of the working zone at that location. When the local maximum dimensional deviation is the cantilever size gradually opening or closing, a pressure adjustment signal is output to the micro high-pressure hydraulic chamber corresponding to the target spatial coordinates to apply reverse prestress to the mold cantilever.

[0040] In this embodiment, based on the location information of the local maximum dimensional deviation in the full-section error matrix, the target spatial coordinates of the deviation on the profile cross-section are determined, which are used to locate the mold elastic compensation layer unit that needs to be activated. Local wall thickness deviation or hole position offset indicates that the mold working zone has undergone local elastic yielding due to high temperature and pressure, or that the metal flow rate at that location is too fast. At this time, a nanosecond-level voltage signal is output to the piezoelectric ceramic actuator corresponding to the target spatial coordinates, causing it to extend from 0 to 100 micrometers, increasing the effective friction length of the working zone at that location, thereby limiting the local metal flow rate and restoring the wall thickness to within the tolerance range. The gradual opening or closing of the cantilever size indicates that the core cantilever position of the mold has undergone thermal fatigue creep deformation under long-cycle extrusion. At this time, a pressure adjustment signal is output to the micro-high pressure hydraulic chamber corresponding to the back of the cantilever, applying reverse prestress to the mold cantilever, forcing it to reset, thereby correcting the cantilever size of the open profile.

[0041] Furthermore, based on any of the above embodiments, a fifth embodiment of the present invention for an online monitoring and compensation control method for dimensional accuracy in an aluminum profile extrusion process is proposed. The first-order macroscopic control command and the second-order microscopic control command are executed decoupled. Specifically, when the local maximum dimensional deviation exceeds a preset tolerance threshold and the overall deformation trend does not exceed a preset deformation threshold, only the second-order microscopic control command is executed, while the first-order macroscopic control command remains in its current state. Conversely, when the overall deformation trend exceeds a preset deformation threshold and the local maximum dimensional deviation does not exceed a preset tolerance threshold, only the first-order macroscopic control command is executed, while the second-order microscopic control command remains in its current state.

[0042] In this embodiment, decoupled execution is one of the core control logics of the solution. When only local wall thickness deviations exist while the overall deformation trend is normal, the first-order process parameters remain unchanged, and the second-order elastic compensation layer independently completes the micron-level correction, avoiding interference from macroscopic adjustments to local accuracy. When only overall bending exists while local dimensions are within acceptable limits, the problem is solved by wind pressure and elongation rate, and the second-order compensation layer is not triggered, avoiding the impact of microscopic adjustments on overall deformation. This decoupled control design, compared to the blind adjustment mode of traditional technology where everything moves with a single change, can effectively reduce the tolerance fluctuation range.

[0043] Furthermore, this invention also proposes an online monitoring and compensation control device for the dimensional accuracy of aluminum profiles during the extrusion process. The online monitoring and compensation control device for the dimensional accuracy of aluminum profiles during the extrusion process includes: The acquisition module is used to acquire real-time cross-sectional data of hot aluminum profiles. The real-time cross-sectional data includes: hot cross-sectional point cloud data, hot characteristic dimension data, and cross-sectional temperature field data. The modeling module is used to determine the cold cross-section geometric model based on the real-time cross-section data; The analysis module is used to determine dimensional deviation data based on the cold-state cross-sectional geometric model and the preset design model; The control module is used to generate two-stage compensation control instructions based on the dimensional deviation data. The two-stage compensation control instructions include: a first-stage macro control instruction and a second-stage micro control instruction. The first-stage macro control instruction is used to regulate the extrusion speed and the zoned cooling air pressure, and the second-stage micro control instruction is used to control the mold elastic compensation layer.

[0044] Furthermore, this invention also proposes an online monitoring and compensation control device for the dimensional accuracy of an aluminum profile extrusion process. The device includes a memory, a processor, and an online monitoring and compensation control program for the dimensional accuracy of an aluminum profile extrusion process stored in the memory and executable on the processor. The program is configured to implement the steps of the online monitoring and compensation control method for the dimensional accuracy of an aluminum profile extrusion process as described above.

[0045] Furthermore, this embodiment of the invention also proposes a storage medium storing an online monitoring and compensation control program for the dimensional accuracy of the aluminum profile extrusion process. When the processor executes the online monitoring and compensation control program for the dimensional accuracy of the aluminum profile extrusion process, it implements the steps of the online monitoring and compensation control method for the dimensional accuracy of the aluminum profile extrusion process described above.

[0046] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or system that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or system. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or system that includes that element.

[0047] The sequence numbers of the above embodiments of the present invention are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0048] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) as described above, and includes several instructions to cause a terminal device (which may be a mobile phone, computer, server, or network device, etc.) to execute the methods described in the various embodiments of the present invention.

[0049] The above are merely preferred embodiments of the present invention and do not limit the scope of the patent. Any equivalent structural or procedural transformations made based on the description and drawings of the present invention, or direct or indirect applications in other related technical fields, are similarly included within the scope of patent protection of the present invention.

Claims

1. A method for online monitoring and compensation control of dimensional accuracy in the aluminum profile extrusion process, characterized in that, The method for online monitoring and compensation control of dimensional accuracy during the aluminum profile extrusion process includes the following steps: Real-time cross-sectional data of hot aluminum profiles are obtained, including: hot cross-sectional point cloud data, hot characteristic dimension data, and cross-sectional temperature field data; The cold-state cross-section geometric model is determined based on the real-time cross-section data; The dimensional deviation data are determined based on the cold-state cross-sectional geometric model and the preset design model; Based on the dimensional deviation data, a two-stage compensation control instruction is generated. The two-stage compensation control instruction includes a first-stage macro control instruction and a second-stage micro control instruction. The first-stage macro control instruction is used to regulate the extrusion speed and the zoned cooling air pressure, and the second-stage micro control instruction is used to control the mold elastic compensation layer.

2. The method for online monitoring and compensation control of dimensional accuracy in the aluminum profile extrusion process as described in claim 1, characterized in that, The step of determining the cold cross-section geometric model based on the real-time cross-section data includes: Obtain the preset material dynamic thermal shrinkage matrix; Based on the cross-sectional temperature field data and the material dynamic thermal shrinkage matrix, nonlinear reverse shrinkage calculations are performed on the hot cross-sectional point cloud data and the hot characteristic size data to obtain the cold cross-sectional geometric model.

3. The method for online monitoring and compensation control of dimensional accuracy in the aluminum profile extrusion process as described in claim 1, characterized in that, The step of determining the dimensional deviation data based on the cold-state cross-sectional geometric model and the preset design model includes: Align the cold-state cross-section geometric model with the preset design model in spatial coordinate system; Boolean difference operation is performed on the aligned cold cross-section geometric model and the preset design model to generate the full cross-section error matrix; The dimensional deviation data is determined based on the full cross-section error matrix, and the dimensional deviation data includes: local maximum dimensional deviation and overall deformation trend.

4. The method for online monitoring and compensation control of dimensional accuracy in the aluminum profile extrusion process as described in claim 1, characterized in that, The step of generating a two-order compensation control command based on the size deviation data includes: When the overall deformation trend exceeds the preset deformation threshold, the first-order macroscopic control command is generated. When the local maximum size deviation exceeds the preset tolerance threshold, the second-order micro-control command is generated.

5. The method for online monitoring and compensation control of dimensional accuracy in the aluminum profile extrusion process as described in claim 4, characterized in that, The step of generating the first-order macroscopic control command when the overall deformation trend exceeds the preset deformation threshold includes: When the overall deformation trend is that the overall wall thickness is thinner or thicker in the same direction, a first speed adjustment command is generated to reduce or increase the extruder main plunger advance speed. When the overall deformation trend is overall bending or asymmetrical twisting, a first wind pressure adjustment command and a stretching straightening rate adjustment command are generated. The first wind pressure adjustment command is used to increase the wind pressure of the zoned cooling fan on the thinned side or the inner bending side, and the stretching straightening rate adjustment command is used to adjust the online stretching straightening rate towards the upper limit of the fitting.

6. The method for online monitoring and compensation control of dimensional accuracy in the aluminum profile extrusion process as described in claim 4, characterized in that, The step of generating the second-order microscopic control command when the local maximum size deviation exceeds the preset tolerance threshold includes: Calculate the target spatial coordinates of the local maximum dimensional deviation on the profile cross-section; When the local maximum dimensional deviation is a local wall thickness deviation or hole position offset, an elongation drive signal is output to the piezoelectric ceramic actuator corresponding to the target spatial coordinates to increase the frictional resistance of the working zone at that location. When the local maximum dimensional deviation is the cantilever size gradually opening or closing, a pressure adjustment signal is output to the micro high-pressure hydraulic chamber corresponding to the target spatial coordinates to apply reverse prestress to the mold cantilever.

7. The method for online monitoring and compensation control of dimensional accuracy in the aluminum profile extrusion process as described in any one of claims 1 to 6, characterized in that, The first-order macroscopic control command and the second-order microscopic control command are executed in a decoupled manner. When the local maximum dimensional deviation exceeds a preset tolerance threshold and the overall deformation trend does not exceed a preset deformation threshold, only the second-order microscopic control command is executed, and the first-order macroscopic control command remains in its current state. When the overall deformation trend exceeds a preset deformation threshold and the local maximum dimensional deviation does not exceed a preset tolerance threshold, only the first-order macroscopic control command is executed, and the second-order microscopic control command remains in its current state.

8. A device for online monitoring and compensation control of dimensional accuracy in the aluminum profile extrusion process, characterized in that, The online monitoring and compensation control device for dimensional accuracy during the aluminum profile extrusion process includes: The acquisition module is used to acquire real-time cross-sectional data of hot aluminum profiles. The real-time cross-sectional data includes: hot cross-sectional point cloud data, hot characteristic dimension data, and cross-sectional temperature field data. The modeling module is used to determine the cold cross-section geometric model based on the real-time cross-section data; The analysis module is used to determine dimensional deviation data based on the cold-state cross-sectional geometric model and the preset design model; The control module is used to generate two-stage compensation control instructions based on the dimensional deviation data. The two-stage compensation control instructions include: a first-stage macro control instruction and a second-stage micro control instruction. The first-stage macro control instruction is used to regulate the extrusion speed and the zoned cooling air pressure, and the second-stage micro control instruction is used to control the mold elastic compensation layer.

9. An online monitoring and compensation control device for dimensional accuracy in the aluminum profile extrusion process, characterized in that, The online monitoring and compensation control device for dimensional accuracy of the aluminum profile extrusion process includes: a memory, a processor, and an online monitoring and compensation control program for dimensional accuracy of the aluminum profile extrusion process stored in the memory and executable on the processor. The online monitoring and compensation control program for dimensional accuracy of the aluminum profile extrusion process is configured to implement the steps of the online monitoring and compensation control method for dimensional accuracy of the aluminum profile extrusion process as described in any one of claims 1 to 7.

10. A storage medium, characterized in that, The storage medium stores an online monitoring and compensation control program for the dimensional accuracy of the aluminum profile extrusion process. When the processor executes the online monitoring and compensation control program for the dimensional accuracy of the aluminum profile extrusion process, it implements the steps of the online monitoring and compensation control method for the dimensional accuracy of the aluminum profile extrusion process as described in any one of claims 1 to 7.

Images