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CN-121832312-B - Method and system for optimizing drawing forming parameters of special-shaped steel bar

CN121832312BCN 121832312 BCN121832312 BCN 121832312BCN-121832312-B

Abstract

The application relates to the technical field of metal plastic processing, and discloses a method and a system for optimizing drawing forming parameters of a special-shaped steel bar. The method comprises the steps of extracting geometric features of a special-shaped cross section, carrying out flow field simulation to generate a flow velocity distribution map, identifying potential vortex areas through velocity gradient analysis and determining an influence range of the potential vortex areas, tracking material flow paths in the influence range to generate a vortex intensity distribution map, carrying out correlation analysis on vortex intensity distribution map and wall thickness deviation data, adjusting lubrication process parameters to generate a lubrication condition distribution map, carrying out superposition mapping on the lubrication condition distribution map and the flow velocity distribution map, analyzing influences of shearing extrusion stress on wall thickness evolution, determining a drawing velocity compensation field, updating simulation parameters according to the drawing velocity compensation field to generate a wall thickness prediction distribution map, carrying out iterative calculation on the drawing velocity compensation field by taking wall thickness uniformity as an objective function through an optimization algorithm to generate drawing molding control parameters. The application improves the uniformity of the wall thickness of the special-shaped steel bar and the processing precision.

Inventors

  • WANG XINYUAN

Assignees

  • 浙江高昶机械五金有限公司

Dates

Publication Date
20260508
Application Date
20260313

Claims (9)

  1. 1. The method for optimizing the drawing forming parameters of the special-shaped steel bar is characterized by comprising the following steps of: S1, extracting geometric features of special-shaped section data, and performing flow field simulation based on the geometric features to generate a preliminary flow velocity distribution diagram; s2, carrying out velocity gradient analysis according to the flow velocity distribution diagram, identifying potential vortex areas with abnormal velocity gradients, and determining the influence range of the potential vortex areas; s3, tracking a flow path of the material in the influence range, and generating an eddy current intensity distribution diagram according to a tracking result; S4, performing correlation analysis on the vortex intensity distribution map and preset wall thickness deviation data, and adjusting lubrication process parameters based on analysis results to generate a lubrication condition distribution map; S5, carrying out space superposition mapping on the lubrication condition distribution diagram and the flow velocity distribution diagram, analyzing the influence of shearing extrusion stress on wall thickness evolution, and determining a drawing speed compensation field for correcting flow unevenness; s6, updating flow field simulation parameters according to the drawing speed compensation field, recalculating a material flow path, and generating a corresponding wall thickness prediction distribution diagram; And S7, carrying out iterative computation on the drawing speed compensation field by using the uniformity of the wall thickness prediction distribution diagram as an objective function through an optimization algorithm, and generating final special-shaped steel rod drawing forming control parameters.
  2. 2. The method of claim 1, wherein S1 comprises: Acquiring a global model space corresponding to the special-shaped section data, and performing initial grid division of basic density on the global model space; Extracting geometric corner features and curvature abrupt change features from the special-shaped section data through a finite element simulation tool; performing high-density meshing on the local area where the geometric corner feature and the curvature mutation feature are located on the basis of the basic density, and performing further self-adaptive encryption adjustment on the mesh density of any local area if the curvature mutation value of any local area is detected to exceed a preset mutation threshold value; Acquiring initial distribution data of the lubricant on the surface of the special-shaped steel bar, wherein the initial distribution data at least comprises the thickness of a lubricant coating and the viscosity grade of the lubricant; And generating the flow velocity distribution map through finite element simulation calculation based on the meshing result and the initial distribution data.
  3. 3. The method of claim 1, wherein S2 comprises: extracting velocity gradient data of each local area from the flow velocity distribution map; comparing the speed gradient data with a preset speed gradient threshold range, if the speed gradient data of any local area exceeds the speed gradient threshold range, judging the local area as a potential vortex area, and extracting the space coordinates of the potential vortex area; establishing a local addressing space by taking the space coordinates of the potential vortex area as a reference, acquiring a distribution uniformity index and local accumulation characteristic data of the lubricant in the local addressing space, and further analyzing the disturbance influence of the potential vortex area on the flow of peripheral materials; and according to the analysis result of the disturbance influence, determining the influence range of the potential vortex region by using the space coordinates of the potential vortex region as a reference through a boundary expansion algorithm.
  4. 4. The method of claim 1, wherein S3 comprises: in the influence range of the potential vortex area, adopting a virtual particle image velocimetry technology based on flow field simulation, tracking an equivalent flow path of a material in the potential vortex area, and extracting corresponding path deviation vector data; Acquiring nonlinear interface parameters corresponding to the equivalent flow path, wherein the nonlinear interface parameters at least comprise dynamic friction coefficients between the lubricant and the forming material and high-temperature stability parameters representing the heat generation state of the lubricant under shearing; combining the path deviation vector data with the nonlinear interface parameters, calculating local energy dissipation rate caused by flow disturbance based on an energy dissipation model, further generating the vortex intensity distribution diagram, and positioning and marking a vortex core position in the vortex intensity distribution diagram; and extracting peak intensity data of the vortex core position, and if the peak intensity data exceeds a preset vortex intensity threshold value, carrying out refined tracking analysis on the flow path of the vortex core position and the surrounding area of the vortex core position, and iteratively generating an updated vortex intensity distribution map until the accuracy requirement is met.
  5. 5. The method of claim 1, wherein S4 comprises: Carrying out space superposition comparison on the vortex intensity distribution diagram and the wall thickness deviation data, and identifying a key influence area in which the vortex intensity is higher than a preset intensity threshold value and the wall thickness deviation exceeds a preset diagnosis deviation range; Establishing a negative correlation response model of the vortex intensity and the friction coefficient of the lubrication interface aiming at the key influence area, and calculating a target friction coefficient distribution for inhibiting the vortex intensity based on the negative correlation response model; According to the target friction coefficient distribution, reversely solving corresponding lubrication process parameters through a preset lubrication mechanism function, wherein the lubrication process parameters at least comprise a lubricant application pressure range aiming at the key influence area and a dynamic update frequency of lubricant supply; and generating a lubrication condition distribution diagram based on the lubrication process parameters, and recording the change trend data of the local accumulation state of the lubricant in the key influence area under the adjustment of the lubrication process parameters so as to quantitatively represent the inhibition effect of the distribution state of the lubricant on the vortex intensity.
  6. 6. The method of claim 1, wherein S5 comprises: unifying the lubrication condition distribution diagram and the flow velocity distribution diagram to the same space coordinate system for space superposition mapping, and constructing a coupling physical model representing the association of a friction boundary and internal kinematics; Based on the coupling physical model, calculating the shearing extrusion stress distribution of each local area of the special-shaped section, and quantitatively analyzing the influence of the shearing extrusion stress distribution on the plastic deformation of the material by combining the incompressible principle of the volume of the material, and predicting the wall thickness deviation variance of the output local area; if the wall thickness deviation evolution quantity of any local area exceeds a preset allowable forming tolerance range, reversely calculating a drawing speed local adjustment vector of the corresponding local area with the aim of counteracting the wall thickness deviation evolution quantity; Extracting the drawing speed local adjustment vectors of each local area, introducing a drawing speed distribution uniformity correction mechanism based on space smoothing filtering or spline interpolation, and fitting and reconstructing the discrete drawing speed local adjustment vectors into a continuous drawing speed compensation field.
  7. 7. The method of claim 1, wherein S6 comprises: The drawing speed compensation field is used as a new kinematic boundary condition to replace or be overlapped on an initial drawing speed boundary of flow field simulation, so that the updating of flow field simulation parameters is completed; Driving a finite element solver by using the updated flow field simulation parameters, recalculating a material flow path in the drawing forming process of the special-shaped steel bar, and outputting transient flow field data; based on the recalculated material flow path and the transient flow field data, generating a corresponding wall thickness prediction distribution map through a volume integration or grid node displacement tracking algorithm; comparing the wall thickness prediction distribution map with a preset target wall thickness distribution, and calculating the wall thickness deviation amount of each local area; And if the wall thickness deviation of any partial area exceeds the preset allowable deviation range, triggering a correction instruction of the drawing speed compensation field, and entering step S7.
  8. 8. The method of claim 7, wherein S7 comprises: the uniformity of the wall thickness prediction distribution diagram is maximized as an optimization target, and an objective function with the variance or root mean square error of the wall thickness deviation amount of each local area minimized as a core is constructed; applying a drawing speed region segmentation strategy to a complex flow field containing a potential vortex region, and dividing the drawing speed compensation field into a plurality of independent control sub-regions; The speed compensation regulation and control amplitude values of the drawing speed compensation field in each independent control subarea and the drawing speed instruction transition time representing the speed change smoothness degree of the forming equipment are jointly used as independent variables to be encoded into decision variables of a genetic optimization algorithm; Adopting a genetic optimization algorithm, performing crossing, mutation and selection operation on the decision variable based on the objective function, generating an updated drawing speed compensation field, and returning to S6 for flow field recalculation and wall thickness prediction evaluation; continuously executing iteration closed loop until the objective function converges and the wall thickness deviation of each local area is smaller than a preset allowable deviation range, and stopping iteration; And packing the lubrication condition distribution diagram and the drawing speed compensation field in the final convergence state to generate final drawing forming control parameters of the special-shaped steel bar.
  9. 9. A profiled bar drawing forming parameter optimisation system for implementing a method as claimed in any one of claims 1 to 8, the system comprising: the geometric simulation module is used for extracting geometric features of the special-shaped section data, performing flow field simulation based on the geometric features and generating a preliminary flow velocity distribution diagram; the vortex recognition module is used for carrying out speed gradient analysis according to the flow speed distribution diagram, recognizing potential vortex areas with abnormal speed gradients and determining the influence range of the potential vortex areas; the path tracking module is used for tracking the flow path of the material in the influence range and generating an eddy current intensity distribution diagram according to the tracking result; The lubrication optimization module is used for carrying out correlation analysis on the vortex intensity distribution diagram and preset wall thickness deviation data, adjusting lubrication process parameters based on analysis results and generating a lubrication condition distribution diagram; the speed compensation module is used for carrying out space superposition mapping on the lubrication condition distribution diagram and the flow speed distribution diagram, analyzing the influence of shearing extrusion stress on wall thickness evolution, and determining a drawing speed compensation field for correcting uneven flow; The wall thickness prediction module is used for updating flow field simulation parameters according to the drawing speed compensation field, recalculating a material flow path and generating a corresponding wall thickness prediction distribution diagram; And the parameter optimization module is used for carrying out iterative computation on the drawing speed compensation field by using the uniformity of the wall thickness prediction distribution diagram as an objective function through an optimization algorithm to generate final special-shaped steel rod drawing forming control parameters.

Description

Method and system for optimizing drawing forming parameters of special-shaped steel bar Technical Field The application relates to the technical field of metal plastic processing, in particular to a method and a system for optimizing drawing forming parameters of a special-shaped steel bar. Background The special-shaped steel bar has the characteristics of asymmetric cross sections, multi-curvature turning, local size mutation and the like, so that the requirements of light mechanical structure, functional integration and specific assembly and matching can be met, and the special-shaped steel bar is widely applied to the fields of automobiles, engineering machinery, rail transit, high-end equipment and the like. Compared with round bars or regular sectional materials, the special-shaped steel bars are more prone to phenomena of uneven material flow, partial thinning or stacking and the like in the drawing forming process, so that the problems of uneven wall thickness (or equivalent thickness) distribution, fluctuation of dimensional accuracy, uncontrollable subsequent machining allowance and the like are caused, and the consistency and service reliability of products are affected. The method mainly comprises the steps of setting a process mechanism analysis by experience parameters and simulating auxiliary optimization, carrying out iterative optimization and closed-loop control evolution by data driving, wherein early multi-reliance process personnel set drawing speed, lubricant type and supply mode according to material marks, die structures and drawing pass experiences, obtaining available parameters in a trial-and-correction mode, but the mode has limited adaptability to different cross section shapes and different die states, then, for improving process repeatability, the industry gradually introduces finite element simulation and other means to analyze stress strain and metal flow in the drawing process, optimize parameters such as die angle, face reduction rate, speed and the like according to the analysis, and further, for coping with local flow abnormality of a complicated special-shaped cross section in a corner and curvature mutation area, researching and engineering practice begin to pay attention to coupling influence between friction boundaries, lubrication states and material flow, and attempt to correct a process window by adopting a multi-parameter optimizing method. However, the existing scheme has the defects that on one hand, uneven wall thickness is often related to flow disturbance phenomena such as overlarge local flow velocity gradient, flow separation, vortex/backflow and the like, but the traditional optimization mainly comprises macroscopic process parameters, reliable identification and quantitative characterization of disturbance areas are difficult, on the other hand, parameters such as lubrication conditions, drawing speed and the like are generally uniformly set as a main part globally, and a spatial compensation and cooperative regulation mechanism aiming at local areas of different sections is lacked, so that the parameter regulation efficiency is low, the parameter is sensitive to working condition change, and the forming result of high wall thickness uniformity is difficult to stably obtain. Therefore, how to effectively identify and quantify the flow disturbance such as material flow velocity distribution and vortex in the drawing and forming process of the special-shaped steel bar, and accordingly realize cooperative optimization and iterative compensation of lubrication parameters and drawing speed, so that the uniformity of wall thickness and the forming stability are improved, and the method is a key technical problem to be solved in the field. Disclosure of Invention Aiming at the problems that uneven wall thickness (or equivalent thickness) and insufficient forming stability are caused by uneven material flow speed distribution, difficult identification and quantification of local flow disorder (such as vortex/reflux) and lack of regional cooperative regulation and control of technological parameters such as lubrication and drawing speed and the like in the conventional special-shaped steel bar drawing forming process due to structural characteristics such as section corners, curvature mutation and the like, the application provides a special-shaped steel bar drawing forming parameter optimization method and system for realizing effective control of wall thickness uniformity. In a first aspect, the application provides a method for optimizing drawing forming parameters of a special-shaped steel bar, which comprises the following steps: S1, extracting geometric features of special-shaped section data, and performing flow field simulation based on the geometric features to generate a preliminary flow velocity distribution diagram; S2, carrying out velocity gradient analysis according to a flow velocity distribution diagram, identifying potential vortex areas with abn