High-efficiency production process of high-strength angle steel and forming preparation method thereof

Abstract

The application discloses a high-efficiency production process and a forming preparation method of high-strength angle steel, and comprises the following steps: raw material selection and pretreatment; segmented step-by-step heating treatment is performed on the pretreated raw material; continuous constant-tension precise rolling is performed on the raw material subjected to the segmented step-by-step heating treatment; fixed-length precise cutting treatment is performed on the raw material subjected to the continuous constant-tension precise rolling; cold bed integrated optimization type segmented temperature control cooling is performed on the raw material subjected to the fixed-length precise cutting treatment; the segmented gradient temperature control cooling mode is adopted to divide the angle steel cooling process into three stages, namely, a high-temperature rapid cooling section, a medium-temperature uniform temperature and pressure stabilization section and a low-temperature shaping slow cooling section; the cold bed integrated optimization type segmented temperature control cooling is matched with synchronous stepping type conveying and dynamic air volume self-adaptive adjustment, which comprises the following steps: based on an AI dynamic air volume calculation model and an AI deformation pre-judgment speed regulation model, the angle steel specification and the cooling state are matched in real time, and the conveying parameters and the ventilation parameters are self-adaptively adjusted; subsequent straightening, finishing and warehousing are performed on the material.

Description

Technical Field

[0001] This invention belongs to the field of hot rolling forming and processing technology of metal profiles, specifically involving an efficient production process and forming method for high-strength angle steel. It is applicable to the industrial continuous hot rolling production, cooling and shaping and finishing of various equal and unequal angle steels, and belongs to the field of refined manufacturing and efficient production technology of steel profiles. Background Technology

[0002] Angle steel, as a core basic material in steel structure buildings, machinery manufacturing, power towers, bridge engineering, and rail transit, is widely used in various industrial and civil construction projects due to its strong structural stability, excellent load-bearing capacity, and convenient assembly. With the rapid development of my country's steel structure industry towards high precision, high strength, long service life, and large-scale production, the market has placed higher technical demands on the dimensional accuracy, surface quality, mechanical property consistency, microstructure uniformity, and production efficiency of angle steel products.

[0003] Currently, the traditional industrial production process for angle steel in China generally adopts a conventional production flow of "raw material heating - continuous rolling - cut to length - natural air cooling / conventional cooling bed cooling - straightening and finishing". The overall production process is scattered, with poor matching between processes, resulting in obvious technical shortcomings and production defects. First, the heating process in traditional production processes mostly adopts a constant temperature heating mode, without segmented gradient control during the billet heating process. This leads to an excessive difference in heating rate between the surface and core of the billet, resulting in uneven temperature gradients inside the billet. After rolling, initial residual stress exists inside the profile, creating hidden dangers for subsequent deformation defects. Second, the tension control stability of traditional rolling processes is poor, with large tension fluctuations between stands. This easily causes forming defects such as deviations in angle steel cross-sectional dimensions, flange asymmetry, and uneven web thickness, reducing the dimensional accuracy of the product.

[0004] The most critical technical flaw lies in the cooling bed process. Traditional cooling beds employ a crude cooling model with uniform airflow and conveying speed across the entire area, failing to differentiate parameters based on the metallographic evolution and heat dissipation characteristics of angle steel at different cooling stages (high, medium, and low temperatures). After rolling and cutting, angle steel is generally at temperatures above 900℃. Traditional cooling methods cannot meet the heat dissipation requirements of different temperature ranges. In the high-temperature stage, a slow cooling rate leads to coarse grains and reduced profile strength. In the medium-temperature stage, uneven temperature fields cause inconsistent shrinkage rates in the flanges and webs, resulting in deformation problems such as bending, twisting, and warping. In the low-temperature stage, rapid cooling causes internal residual stress concentration, resulting in large dispersion in the mechanical properties of the finished angle steel and poor batch consistency. Subsequent straightening processes cannot completely eliminate internal stress, making the product prone to deformation failure and reduced load-bearing capacity during long-term use.

[0005] Meanwhile, in traditional production processes, the production cycle time of each step is independently controlled, and the connection between heating, rolling, cooling, and straightening processes is lagging, resulting in a large amount of idle redundancy time, a long overall production cycle, and low production efficiency. Conventional technical improvements mostly focus on optimizing single rolling or straightening equipment, without systematically integrating and optimizing the entire process, especially the core cooling process of the cooling bed. The improvement effect is limited, and most improvement solutions require the addition of large-scale production equipment, resulting in high equipment investment and modification costs and low cost-effectiveness for industrialization.

[0006] Furthermore, existing angle steel production processes lack intelligent dynamic control mechanisms. Cooling airflow and conveying speed are set with fixed parameters, making it impossible to adaptively adjust based on the real-time temperature, dimensions, and deformation trends of the angle steel. This makes it difficult to meet the production needs of different angle steel models, hindering the improvement of product qualification rates and production stability. Based on these numerous shortcomings of traditional technologies, there is an urgent need to develop a high-strength angle steel production process that optimizes the entire process, integrates and upgrades the cooling bed system, implements intelligent and precise control, and achieves low cost and high efficiency. This process would solve the technical problems of severe deformation, uneven performance, and low efficiency inherent in traditional processes. Summary of the Invention

[0007] The purpose of this invention is to overcome the technical defects of existing traditional angle steel production processes, such as lengthy processes, uneven cooling, large profile deformation, concentrated residual stress, poor consistency of mechanical properties, low process cycle matching, low production efficiency, and high modification costs. This invention provides a highly efficient production process and forming method for high-strength angle steel. Through a fully integrated and optimized design encompassing precise raw material selection, segmented stepped heating, constant tension precision rolling, precise length cutting, segmented temperature-controlled cooling on a cooling bed, dynamic adaptive airflow adjustment, synchronous stepping conveyor, and real-time intelligent model control, this invention addresses the shortcomings of traditional technologies from raw material selection, forming process, cooling and shaping, to finishing. Without significantly increasing equipment investment, it refines the metallographic structure of the profiles, eliminates deformation defects, unifies mechanical properties, and shortens the production cycle, achieving high-quality, high-efficiency, and low-cost continuous industrial production of angle steel.

[0008] To achieve the above technical objectives, the present invention adopts the following technical solution:

[0009] This invention provides an efficient production process and forming method for high-strength angle steel, comprising:

[0010] S1, Raw material selection and pretreatment;

[0011] S2, the pretreated raw material is subjected to segmented step heating treatment;

[0012] S3, the raw material that has undergone the segmented stepped heating treatment is subjected to continuous constant tension precision rolling;

[0013] S4, the raw material that has undergone continuous constant tension precision rolling is precisely cut to length.

[0014] S5 involves integrating optimized segmented temperature control cooling on a cooling bed to cool the raw material after precise cutting to length. S5 employs a segmented gradient temperature control cooling mode, dividing the angle steel cooling process into three stages: a high-temperature rapid cooling stage, a medium-temperature uniform temperature and pressure stabilization stage, and a low-temperature shaping and slow cooling stage. This achieves differentiated cooling rate control across different temperature ranges. The integrated optimized segmented temperature control cooling on the cooling bed, combined with synchronous step-by-step conveying and dynamic airflow adaptive adjustment, includes: based on an AI dynamic airflow calculation model and an AI deformation prediction speed adjustment model, real-time matching of angle steel specifications and cooling status, and adaptive adjustment of conveying and ventilation parameters.

[0015] S6, perform subsequent straightening, finishing and warehousing on the material that has completed the integrated optimized segmented temperature-controlled cooling of the cooling bed;

[0016] Preferably, the raw material selection and pretreatment in S1 specifically includes: selecting Q235B and Q355B carbon structural steel continuous casting billets as production raw materials, with billet cross-sectional dimensions of 150mm×150mm, 180mm×180mm, and 200mm×200mm, and billet length of 6000mm~12000mm; performing surface pretreatment on the selected steel billets, removing oxide scale, rust, and impurities from the billet surface by shot blasting, and simultaneously flattening and grinding the billet end faces to ensure that the billet surface roughness is ≤6.3μm and the end face flatness error is ≤0.5mm / m; when selecting raw materials, steel billets with carbon content of 0.12%~0.22%, manganese content of 1.20%~1.60%, sulfur content ≤0.035%, and phosphorus content ≤0.035% are preferred.

[0017] Preferably, step S2 includes: using a three-stage walking beam furnace to heat the steel billet, which is divided into a preheating stage, a heating stage, and a soaking stage; wherein the temperature of the preheating stage is controlled at 650℃~750℃, and the preheating holding time is 20min~35min; the temperature of the heating stage is controlled at 950℃~1050℃, and the heating time is 40min~55min; the temperature of the soaking stage is controlled at 1180℃~1220℃, and the soaking holding time is 25min~40min; the excess air coefficient in the furnace is controlled at 1.05~1.15, and the furnace pressure is maintained at -5Pa~5Pa to ensure uniform heating temperature of the steel billet and temperature difference fluctuation ≤±5℃.

[0018] Preferably, S3 includes: employing a multi-pass continuous hot rolling process, with 8 to 12 rolling passes, controlling the initial rolling temperature at 1150℃ to 1190℃, and controlling the final rolling temperature at 900℃ to 950℃; maintaining constant tension between stands during rolling through a tension control system, with a tension control value of 800N to 1500N and a tension fluctuation error ≤ ±30N; adaptively adjusting the roll speed according to the angle steel specifications, with a speed range of 2.5m / s to 5.0m / s, and controlling the rolling dimensional accuracy within ±0.1mm to ensure uniform cross-sectional dimensions and a surface free of rolling scratches and wrinkles after rolling.

[0019] Preferably, S4 includes: using a flying shear machine for online dynamic fixed-length cutting, setting the fixed length of the finished angle steel to 6m to 12m according to production needs, with a cutting response delay time ≤0.2s and a cutting end face perpendicularity error ≤0.3mm; after cutting, removing end burrs and flash defects in real time to ensure that the cutting end face is flat and smooth, without stress concentration gaps, providing a basic forming structure for subsequent uniform cooling.

[0020] Preferably, the integrated optimized segmented temperature-controlled cooling system of the cooling bed in S5 specifically includes: a high-temperature rapid cooling section with a temperature range of 700℃ to 900℃ and a cooling rate controlled at 8℃ / s to 12℃ / s; a medium-temperature uniform temperature and pressure stabilization section with a temperature range of 400℃ to 700℃ and a cooling rate controlled at 3℃ / s to 6℃ / s; and a low-temperature shaping and slow cooling section with a temperature range of room temperature to 400℃ and a cooling rate controlled at 0.5℃ / s to 2℃ / s. The surface and core temperatures of the angle steel are collected in real time throughout the three-stage cooling process to ensure that the temperature difference between the flange and the web of the angle steel is ≤8℃, thereby eliminating deformation stress caused by local temperature differences.

[0021] Preferably, in the synchronous stepping conveying and dynamic air volume adaptive adjustment of S5, the synchronous stepping conveying adopts an intermittent uniform speed stepping mode, with a step distance of 80mm to 150mm, a stepping interval of 1.5s to 3.0s, and the conveying speed is stably controlled at 0.8m / min to 1.5m / min; the dynamic air volume adjustment adopts a zoned independent ventilation structure, dividing the cooling bed into three independent ventilation units: a high-temperature cooling zone, a medium-temperature uniform temperature zone, and a low-temperature shaping zone. The frequency adjustment range of the fan in each unit is 20Hz to 50Hz, and the ventilation air volume adjustment range is 3000m³ / h to 8000m³ / h.

[0022] Preferably, the calculation formula of the AI ​​dynamic air volume calculation model is shown in equation (1):

[0023] (1);

[0024] in, Real-time adaptive ventilation volume, unit m³ / h; The real-time internal and external temperature difference of the angle steel, in °C; The effective heat dissipation surface area of ​​the angle steel, in m²; This refers to the real-time conveying speed of the cooling bed, expressed in m / min. The density of the angle steel is taken as 7.85 g / cm³. The ambient reference temperature is expressed in °C. , , These are adaptive correction coefficients, with values ​​ranging from 0.85 to 0.95, 1.20 to 1.35, and 0.05 to 0.15, respectively.

[0025] Preferably, the calculation formula for the AI ​​deformation prediction speed regulation model is as shown in equation (2):

[0026] (2);

[0027] in, To optimize conveying speed in real time, the unit is m / min; The reference conveying speed is expressed in m / min. This is the real-time deformation deviation coefficient, with a value ranging from 0 to 0.2; This represents the real-time residual stress value of the angle steel, in MPa. The residual stress threshold allowed by the standard for angle steel is 120 MPa.

[0028] Preferably, step S7 includes: feeding the angle steel cooled to room temperature into a multi-roller straightener for overall straightening, with the number of straightening rolls set to 7 to 11 rolls, and the straightening pressure controlled at 30kN to 60kN. After straightening, the straightness error of the angle steel is ≤1.0mm / m, and the torsion error is ≤0.5mm / m. After straightening, surface finishing, dimensional re-inspection, and non-destructive testing are performed. Unqualified products with excessive dimensions, surface defects, or internal cracks are removed, and finally, they are classified, packaged, and stored. The overall production process cycle time is shortened by 15% to 25% compared to traditional processes, and the product mechanical property qualification rate is ≥99.2%.

[0029] The beneficial effects of the method of the present invention are as follows:

[0030] This invention addresses the technical problems in traditional angle steel production by constructing a fully integrated optimization system encompassing raw material optimization, heating and temperature control, precise rolling, intelligent cooling, and cycle time coordination. The technical principles include "uniform temperature field, controllable stress, precise forming, high-efficiency production, and intelligent regulation," which offers significant technical advantages and beneficial effects compared to traditional processes.

[0031] (1) In the raw material and heating forming process, this invention solves the problems of material performance dispersion, uneven heating and high initial stress in traditional processes by accurately selecting raw material composition ratios and using a segmented stepped heating system. This ensures uniform temperature and stable structure of the billet before forming, laying the foundation for high-precision and high-performance profile forming. The constant tension multi-pass rolling process can refine metallographic grains, unify cross-sectional dimensions, improve the structural strength of the profile, avoid rolling deformation and dimensional deviation defects, and the forming accuracy is much higher than that of the traditional extensive rolling process.

[0032] (2) In the core cooling and shaping stage, the innovative three-stage gradient temperature control cooling mode of this invention accurately matches the metallographic evolution and heat dissipation characteristics of angle steel in different temperature ranges, specifically solving the industry problems of coarse grains at high temperatures, phase deformation at medium temperatures, and stress accumulation at low temperatures, and completely breaking through the technical bottleneck of the traditional single cooling mode. The synchronous stepping conveyor and zoned dynamic ventilation structure realize uniform, uniform, and stable heat dissipation in the cooling process, ensuring that the cooling sequence and heat dissipation effect of each batch and each angle steel are completely consistent, greatly improving the consistency of product batches.

[0033] (3) In the intelligent control process, the two sets of AI dynamic calculation models independently constructed by the present invention realize the real-time adaptive iterative optimization of cooling air volume and conveying speed, abandon the limitations of traditional fixed parameter production, and can adapt to the production needs of angle steel of different materials, different specifications and different production conditions. It realizes closed-loop intelligent control of deformation prediction, parameter self-adjustment and defect self-correction, without the need for manual repeated parameter adjustment, thus improving the level of production intelligence and product stability.

[0034] (4) In terms of production efficiency and cost control, the present invention eliminates the standby redundancy time between each process by optimizing the cycle time of the whole process, which greatly shortens the production cycle and increases the production capacity. At the same time, the technology upgrade is achieved only through process modification and control system optimization, without the need to add large-scale production equipment, and the equipment investment and modification costs are extremely low.

[0035] (5) In terms of comprehensive technical effects, the present invention effectively refines the metallographic structure of angle steel, improves the uniformity of the structure and structural strength of the profile, significantly reduces deformation defects such as bending, twisting and warping of the profile, thoroughly improves the consistency of mechanical properties of the product, significantly improves the product qualification rate, dimensional accuracy and surface quality, greatly improves production efficiency, and can be fully adapted to the industrial continuous production of various equal and unequal angle steels, taking into account the production needs of high quality, high efficiency and low cost. Attached Figure Description

[0036] To more clearly illustrate the technical solutions in the specific embodiments or related technologies of the present invention, the drawings used in the description of the specific embodiments or related technologies will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0037] Figure 1 This is a flowchart illustrating an efficient production process and forming method for high-strength angle steel according to an embodiment of the present invention. Detailed Implementation

[0038] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0039] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0040] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0041] like Figure 1 As shown, this embodiment provides an efficient production process and forming method for high-strength angle steel, including:

[0042] S1, Raw material selection and pretreatment;

[0043] S2, the pretreated raw material is subjected to segmented step heating treatment;

[0044] S3, the raw material that has undergone the segmented stepped heating treatment is subjected to continuous constant tension precision rolling;

[0045] S4, the raw material that has undergone continuous constant tension precision rolling is precisely cut to length.

[0046] S5 involves integrating optimized segmented temperature control cooling on a cooling bed to cool the raw material after precise cutting to length. S5 employs a segmented gradient temperature control cooling mode, dividing the angle steel cooling process into three stages: a high-temperature rapid cooling stage, a medium-temperature uniform temperature and pressure stabilization stage, and a low-temperature shaping and slow cooling stage. This achieves differentiated cooling rate control across different temperature ranges. The integrated optimized segmented temperature control cooling on the cooling bed, combined with synchronous step-by-step conveying and dynamic airflow adaptive adjustment, includes: based on an AI dynamic airflow calculation model and an AI deformation prediction speed adjustment model, real-time matching of angle steel specifications and cooling status, and adaptive adjustment of conveying and ventilation parameters.

[0047] S6, the material that has completed the integrated optimized segmented temperature-controlled cooling of the cooling bed is then straightened, finished and put into storage.

[0048] This embodiment adopts a fully integrated optimization approach, defining six steps: raw material pretreatment, stepped heating, constant tension rolling, length cutting, segmented temperature-controlled cooling on a cooling bed (dynamic conveying airflow adjustment), and finishing and warehousing. This constructs a refined, intelligent, and collaborative production system that differs from traditional extensive production methods. The core innovation of this invention lies in the systematic integration and transformation of the cooling bed process. Traditional methods use a single cooling mode; this embodiment innovatively divides the cooling process into three independent stages: high-temperature rapid cooling, medium-temperature uniform temperature and pressure stabilization, and low-temperature shaping and slow cooling. This achieves differentiated rate control at each stage, precisely matching the metallographic transformation and heat dissipation characteristics of angle steel at different temperature ranges. Furthermore, this embodiment introduces two sets of AI dynamic calculation models adapted to angle steel cooling and forming for the first time, enabling real-time adaptive optimization of ventilation airflow and conveying speed. This solves the technical problem that traditional fixed-parameter production cannot adapt to angle steel of different specifications and temperature conditions. The collaborative optimization design of the entire process realizes the rhythm matching and performance linkage of each production link, and controls the quality and production efficiency of profiles from the molding source, cooling process and shaping end. This is the core overall architecture technical solution of the present invention.

[0049] As a preferred embodiment, the raw material selection and pretreatment in S1 specifically includes: selecting Q235B and Q355B carbon structural steel continuous casting billets as production raw materials, with billet cross-sectional dimensions of 150mm×150mm, 180mm×180mm, and 200mm×200mm, and billet length of 6000mm~12000mm; performing surface pretreatment on the selected steel billets, removing oxide scale, rust, and impurities from the billet surface by shot blasting, and simultaneously flattening and grinding the billet end faces to ensure that the billet surface roughness is ≤6.3μm and the end face flatness error is ≤0.5mm / m; when selecting raw materials, steel billets with carbon content of 0.12%~0.22%, manganese content of 1.20%~1.60%, sulfur content ≤0.035%, and phosphorus content ≤0.035% are preferred.

[0050] This embodiment involves precise selection and standardized pretreatment of raw materials, clearly defining the billet material, cross-sectional specifications, length dimensions, and composition parameters, while also establishing standardized surface pretreatment processes. The technical reason for selecting Q235B and Q355B carbon structural steel continuously cast billets is that these two types of steel have a reasonable carbon-manganese ratio, low impurity content, strong plasticity and toughness compatibility, excellent grain refinement effect during high-temperature rolling, and balanced strength, toughness, and deformation resistance of the formed profiles, fully meeting the performance requirements of high-strength angle steel. Furthermore, these billets have low industrial procurement costs, wide applicability, and strong continuous rolling stability, making them suitable for large-scale mass production. The core principle of strictly limiting the carbon, manganese, sulfur, and phosphorus content parameters is as follows: controlling the carbon content between 0.12% and 0.22% ensures sufficient strength and hardness in the steel, while avoiding increased brittleness and decreased weldability due to excessive carbon content; a manganese content of 1.20% to 1.60% effectively refines the metallographic grains of the steel, improves its hardenability and strength, and enhances rolling performance; as harmful impurities in steel, strictly limiting the content of sulfur and phosphorus completely avoids problems such as localized stress concentration, uneven mechanical properties, and cracking and deformation caused by impurity segregation. Limiting the billet size allows for compatibility with the forming parameters of the rolling equipment of this invention, ensuring the stability of the rolling process; surface shot blasting and end-face grinding pretreatment thoroughly remove oxide scale and defects from the billet surface, preventing impurities from being pressed into the profile surface during rolling and causing quality defects; a flat end face prevents forming deviations caused by uneven rolling stress, laying a solid foundation for subsequent high-precision forming and uniform cooling.

[0051] In a preferred embodiment, S2 includes: using a three-stage walking beam furnace to heat the steel billet, which is divided into a preheating stage, a heating stage, and a soaking stage; wherein the temperature of the preheating stage is controlled at 650℃~750℃, and the preheating holding time is 20min~35min; the temperature of the heating stage is controlled at 950℃~1050℃, and the heating time is 40min~55min; the temperature of the soaking stage is controlled at 1180℃~1220℃, and the soaking holding time is 25min~40min; the excess air coefficient in the furnace is controlled at 1.05~1.15, and the furnace pressure is maintained at -5Pa~5Pa to ensure uniform heating temperature of the steel billet and temperature difference fluctuation ≤±5℃.

[0052] This embodiment employs a three-stage stepped heating system, which offers significant technical advantages compared to the traditional single constant-temperature heating process. The core principle behind setting up independent preheating, heating, and soaking sections is as follows: During the heating process of the steel billet from room temperature to high temperature, there are significant differences in the heat conduction rate, grain activation state, and structural stress changes across different temperature ranges. Stepped heating effectively avoids problems such as excessive temperature difference between the billet surface and core, thermal stress concentration, and surface cracking caused by rapid heating. Specifically, the 650℃~750℃ preheating section allows for slow heating of the billet, releasing initial casting residual stress and uniformly increasing the overall temperature of the billet, avoiding a sudden increase in the internal and external temperature gradient caused by direct high-temperature heating; the 950℃~1050℃ heating section quickly raises the billet to the initial rolling temperature range, improving production efficiency; and the 1180℃~1220℃ soaking section ensures a uniform overall temperature of the billet, eliminating localized low-temperature areas and ensuring uniform plastic flow of metal during subsequent rolling, thus preventing rolling deformation and performance deviations from the outset. By strictly controlling the excess air coefficient and furnace pressure in the furnace, the combustion state in the furnace can be precisely controlled, avoiding excessive oxidation and decarburization of the billet caused by excessive air. At the same time, it can prevent heat loss and temperature fluctuations caused by abnormal furnace pressure, and control the overall temperature difference of the billet within ±5℃, maximizing the heating uniformity and providing a stable temperature basis for precise rolling.

[0053] In a preferred embodiment, S3 includes: employing a multi-pass continuous hot rolling process, with 8 to 12 rolling passes, controlling the initial rolling temperature at 1150℃ to 1190℃, and the final rolling temperature at 900℃ to 950℃; maintaining constant tension between stands during rolling through a tension control system, with a tension control value of 800N to 1500N and a tension fluctuation error ≤ ±30N; adaptively adjusting the roll speed according to the angle steel specifications, with a speed range of 2.5m / s to 5.0m / s, and controlling the rolling dimensional accuracy within ±0.1mm to ensure uniform cross-sectional dimensions and a surface free of rolling scratches and wrinkles after rolling.

[0054] This embodiment employs a multi-pass continuous constant tension precision rolling process, limiting the rolling passes, initial rolling temperature, final rolling temperature, rolling tension, and roll speed parameters. The technical principle behind setting 8-12 passes for multi-pass rolling is that multiple passes with small reductions can gradually refine the metallographic grains of the steel, avoiding problems such as uneven metal flow, profile cracking, and dimensional deviations caused by single-pass large reduction rolling, effectively improving the profile forming accuracy and structural strength. The selection of initial rolling temperature (1150℃-1190℃) and final rolling temperature (900℃-950℃) is based on the high-temperature plasticity characteristics of steel. Within this temperature range, the steel exhibits optimal plasticity and moderate deformation resistance, ensuring smooth rolling while avoiding excessively high temperatures that lead to coarse grains and reduced strength, and simultaneously mitigating problems such as high rolling resistance, high equipment wear, and high residual stress in the profile caused by excessively low temperatures. Constant tension control of 800N to 1500N completely solves the problem of large tension fluctuations between traditional rolling mill stands. Stable tension ensures matching of metal feed and discharge rates in each pass, eliminating stretching and compression deformation of the profiles and guaranteeing symmetrical flanges, flat webs, and uniform cross-sectional dimensions for the angle steel. Adaptive roll speed adjustment can accommodate the rolling needs of angle steel of different specifications, balancing the stability of large-size profile rolling with the efficiency of small-size profile rolling, controlling rolling dimensional accuracy to ±0.1mm, and significantly improving the dimensional accuracy and consistency of the finished product.

[0055] In a preferred embodiment, S4 includes: using a flying shear machine for online dynamic fixed-length cutting, setting the fixed length of the finished angle steel to 6m to 12m according to production needs, with a cutting response delay time ≤0.2s and a cutting end face perpendicularity error ≤0.3mm; after cutting, removing end burrs and flash defects in real time to ensure that the cutting end face is flat and smooth, without stress concentration gaps, providing a basic forming structure for subsequent uniform cooling.

[0056] This embodiment employs an online dynamic length-cutting process to precisely control cutting accuracy and end-face quality. The online dynamic cutting of the flying shear machine enables seamless integration of rolling and cutting processes, eliminating the need for offline secondary processing, significantly shortening the production process and improving efficiency. A cutting response delay of ≤0.2s ensures the accuracy of length-cutting, avoiding length deviations caused by fluctuations in rolling feed speed. High-precision control with an end-face perpendicularity error of ≤0.3mm ensures that each section of angle steel billet has a flat and regular end face, resulting in uniform stress and symmetrical heat dissipation during subsequent cooling. This prevents problems such as abnormal heat dissipation, stress concentration, and end deformation / bending caused by end-face tilting, burrs, or flash. Real-time removal of end burrs and flash after cutting eliminates stress gaps at the profile ends, preventing end cracking and deformation defects during subsequent cooling and straightening, and ensuring the overall structural integrity and forming accuracy of the profile.

[0057] As a preferred embodiment, the integrated optimized segmented temperature-controlled cooling system of the cooling bed in S5 specifically includes: a high-temperature rapid cooling section with a temperature range of 700℃ to 900℃ and a cooling rate controlled at 8℃ / s to 12℃ / s; a medium-temperature uniform temperature and pressure stabilization section with a temperature range of 400℃ to 700℃ and a cooling rate controlled at 3℃ / s to 6℃ / s; and a low-temperature shaping and slow cooling section with a temperature range of room temperature to 400℃ and a cooling rate controlled at 0.5℃ / s to 2℃ / s. The surface and core temperatures of the angle steel are collected in real time throughout the three-stage cooling process to ensure that the temperature difference between the flange and the web of the angle steel is ≤8℃, thereby eliminating deformation stress caused by local temperature differences.

[0058] In this embodiment, the segmented gradient temperature-controlled cooling process precisely sets the cooling rate based on the metallographic evolution law, thermal conductivity, and deformation stress change characteristics of angle steel in different temperature ranges. The high-temperature rapid cooling section from 900℃ to 700℃ is the stable austenitic structure range of the steel. During this stage, the steel has good plasticity and low deformation stress sensitivity. A rapid cooling rate of 8℃ / s to 12℃ / s is adopted to quickly remove the residual heat from the rolling of the profile, inhibit the continuous growth of austenitic grains at high temperatures, refine the metallographic structure, improve the overall strength and hardness of the profile, and at the same time avoid surface oxidation and decarburization defects caused by prolonged high-temperature exposure, thereby improving the surface quality of the profile. The 700℃~400℃ medium-temperature uniform cooling and pressure stabilization section is the core phase transformation range from austenite to ferrite and pearlite. During this stage, the metallographic transformation is unstable and the deformation sensitivity is extremely high. This is the core temperature range where bending and torsional deformation occur in traditional processes. Therefore, a medium-speed uniform cooling of 3℃ / s~6℃ / s is adopted, with strict control of the cooling rate to ensure synchronous heat dissipation and phase transformation between the angle steel flange and web. This eliminates the structural stress and deformation deviations caused by differences in the phase transformation sequence in different parts, achieving overall temperature uniformity and pressure stabilization of the profile. In the low-temperature shaping and slow cooling section below 400℃, the steel's metallographic transformation is basically complete, and the overall profile structure is stabilized. A low-speed slow cooling mode of 0.5℃ / s~2℃ / s is adopted to slowly release residual stress inside the profile, avoiding stress lock-in and residual stress accumulation problems caused by rapid low-temperature cooling, and significantly improving the dimensional stability and mechanical property consistency of the profile. By controlling the temperature difference between the inside and outside of the profile to ≤8℃ throughout the process, uneven shrinkage and deformation caused by local temperature differences can be completely eliminated, solving the deformation defects of traditional profiles from the root cause of cooling.

[0059] In a preferred embodiment, in the synchronous stepping conveying and dynamic air volume adaptive adjustment of S5, the synchronous stepping conveying adopts an intermittent uniform speed stepping mode, with a step distance of 80mm to 150mm, a stepping interval of 1.5s to 3.0s, and the conveying speed is stably controlled at 0.8m / min to 1.5m / min; the dynamic air volume adjustment adopts a zoned independent ventilation structure, dividing the cooling bed into three independent ventilation units: a high-temperature cooling zone, a medium-temperature uniform temperature zone, and a low-temperature shaping zone. The frequency adjustment range of the fan in each unit is 20Hz to 50Hz, and the ventilation air volume adjustment range is 3000m³ / h to 8000m³ / h.

[0060] This embodiment integrates and optimizes the traditional cooling bed conveying and ventilation system using synchronous stepping conveying and zoned dynamic airflow adaptive adjustment technology. The synchronous stepping conveying mode solves the problems of traditional continuous uniform speed conveying. Through intermittent stepping conveying with a step distance of 80mm to 150mm and an interval of 1.5s to 3.0s, the angle steel can be fully stationary for heat dissipation during the cooling process, avoiding the problems of profile swaying, offset, and uneven stress caused by continuous movement. Simultaneously, it ensures that the conveying trajectory and heat dissipation time of each angle steel are completely consistent, achieving batch-to-batch cooling consistency. The stable conveying speed of 0.8m / min to 1.5m / min can precisely match the duration requirements of the three cooling processes, ensuring that the profile passes through the high-temperature, medium-temperature, and low-temperature cooling zones sequentially, achieving precise matching of process sequence. The zoned independent ventilation structure precisely corresponds the cooling bed to the three cooling zones. Each ventilation unit independently controls the fan frequency of 20Hz to 50Hz and the ventilation volume of 3000m³ / h to 8000m³ / h, which can be specifically matched to the heat dissipation requirements of different cooling stages. The high-temperature zone has a large air volume for rapid heat dissipation, the medium-temperature zone has a moderate air volume for uniform temperature, and the low-temperature zone has a small air volume for slow cooling. This completely solves the problems of poor cooling adaptability and uneven temperature field caused by the uniform air volume throughout the traditional cooling bed, and maximizes the improvement of cooling control accuracy and profile shaping quality.

[0061] As a preferred embodiment, the calculation formula of the AI ​​dynamic air volume calculation model is shown in equation (1):

[0062] (1);

[0063] in, Real-time adaptive ventilation volume, unit m³ / h; The real-time internal and external temperature difference of the angle steel, in °C; The effective heat dissipation surface area of ​​the angle steel, in m²; This refers to the real-time conveying speed of the cooling bed, expressed in m / min. The density of the angle steel is taken as 7.85 g / cm³. The ambient reference temperature is expressed in °C. , , These are adaptive correction coefficients, with values ​​ranging from 0.85 to 0.95, 1.20 to 1.35, and 0.05 to 0.15, respectively.

[0064] In this embodiment, the AI ​​dynamic airflow calculation model is based on the coupling theory of heat conduction, convection heat dissipation, and profile deformation to construct a real-time iterative calculation system. Each parameter in the formula has a clear technical and physical meaning. The core principle of this model is to adaptively calculate the optimal ventilation airflow by real-time collection of key production parameters such as the internal and external temperature difference of the angle steel, heat dissipation area, conveying speed, and ambient temperature, replacing the traditional fixed airflow parameter mode. Among these parameters, the temperature difference... As a basis for control, the greater the temperature difference, the greater the required heat dissipation airflow, in order to quickly balance the temperature field of the profile; heat dissipation surface area To match the dimensional differences of angle steel of different specifications, differentiated airflow control is achieved for different profile models; conveying speed This directly affects the heat dissipation time of the profile; the faster the speed, the larger the airflow needs to be to ensure matching heat dissipation efficiency; ambient temperature Corrects for interference from the external environment on cooling performance, avoiding fluctuations in cooling quality caused by seasonal and ambient temperature changes; three sets of correction coefficients. , , Through extensive industrial trials and iterative optimization, it has been found that the model parameters can be accurately and adaptively corrected, ensuring the accuracy and real-time performance of airflow calculation under different production conditions and profile specifications, realizing intelligent and precise control of cooling airflow, and ensuring a uniform and stable cooling temperature field.

[0065] As a preferred embodiment, the calculation formula of the AI ​​deformation prediction speed regulation model is as shown in equation (2):

[0066] (2);

[0067] in, To optimize conveying speed in real time, the unit is m / min; The reference conveying speed is expressed in m / min. This is the real-time deformation deviation coefficient, with a value ranging from 0 to 0.2; This represents the real-time residual stress value of the angle steel, in MPa. The residual stress threshold allowed by the standard for angle steel is 120 MPa.

[0068] The AI ​​deformation prediction and speed regulation model in this embodiment is built based on the coupling relationship between residual stress and deformation deviation of the profile. Its core function is to predict the cooling deformation trend of the angle steel in real time and adaptively optimize the cooling bed conveyor speed. In the formula, the reference speed V0 is the optimal conveyor speed under normal working conditions, and the deformation deviation coefficient η provides real-time feedback on the current deformation state of the profile. When a slight deformation trend is detected, the value of η increases, automatically reducing the conveyor speed, extending the heat dissipation resting time, and correcting the deformation deviation. The residual stress ratio √(σ_t / σ0) is the core control factor, which compares the current residual stress with the standard threshold in real time. The higher the residual stress, the more appropriately the conveyor speed is reduced to slow down the cooling rhythm, promote the slow release of internal stress, and avoid deformation defects caused by continuous stress accumulation. This model can realize closed-loop intelligent control of deformation prediction, dynamic speed regulation, and deviation correction, further ensuring the profile shaping accuracy from the perspective of conveyor rhythm and significantly reducing the deformation defect rate.

[0069] In a preferred embodiment, step S7 includes: feeding the angle steel cooled to room temperature into a multi-roller straightener for overall straightening, with the number of straightening rolls set to 7 to 11 rolls, and the straightening pressure controlled at 30kN to 60kN. After straightening, the straightness error of the angle steel is ≤1.0mm / m, and the torsion error is ≤0.5mm / m. After straightening, surface finishing, dimensional re-inspection, and non-destructive testing are performed. Unqualified products with excessive dimensions, surface defects, or internal cracks are removed, and finally, they are classified, packaged, and stored. The overall production process cycle time is shortened by 15% to 25% compared to traditional processes, and the product mechanical property qualification rate is ≥99.2%.

[0070] In this embodiment, standardized process parameters are defined for subsequent straightening, finishing, and warehousing, constructing a complete finished product quality assurance system. 7-11 roll multi-roll straightening enables precise straightening of angle steel from all directions and angles. A controllable straightening pressure of 30kN-60kN precisely eliminates minor bending and torsional deformations generated during cooling, while avoiding secondary deformation and stress damage caused by excessive straightening pressure. Straightness and torsion errors are strictly controlled within the industry's high-precision standard range. Subsequent dimensional re-inspection and non-destructive testing thoroughly eliminate unqualified products with outdated dimensions, internal cracks, and surface defects, ensuring the overall quality stability of the finished product. Through optimized matching of all processes, this invention effectively solves the problems of redundant cycle times and delayed connections in traditional processes, shortening the overall production cycle by 15%-25%, significantly improving industrial production efficiency. Simultaneously, the product mechanical property qualification rate is increased to over 99.2%, mechanical property dispersion is significantly reduced, and batch consistency is significantly improved. High-quality, high-efficiency, and low-cost large-scale production is achieved without adding large-scale equipment, only by optimizing process parameters and the control system.

[0071] The technical solution of the present invention will be described in detail and completely below with reference to two specific application embodiments. This embodiment is based on the core process system of the present invention. Without changing the overall technical concept and core technical features of the present invention, it is adapted to the industrial production of angle steel of different specifications, and verifies the feasibility, stability and technical advantages of the process of the present invention.

[0072] Application Example 1: High-efficiency production process of Q355B unequal angle steel (100mm×80mm×8mm)

[0073] This embodiment focuses on the industrial continuous production of Q355B high-strength unequal angle steel (100mm×80mm×8mm) specifically for industrial equipment supports and steel structure frames. The optimized process of this invention is employed, and the specific production steps and parameters are as follows:

[0074] S1. Raw Material Selection and Pretreatment: Q355B continuously cast steel billets with a cross-section of 180mm×180mm and a length of 9000mm are selected. The billet composition is strictly controlled to have a carbon content of 0.18%, a manganese content of 1.45%, a sulfur content of 0.028%, and a phosphorus content of 0.030%, with impurity content below the national standard limits. The billets undergo fully automated shot blasting to remove surface oxide scale and rust. The end faces of the billets are ground to control the surface roughness at 5.2μm and the end face flatness error at 0.3mm / m. After cleaning, surface impurities are blown away to ensure that the billets are clean and defect-free. The technical advantages of this raw material selection are that Q355B material has the characteristics of high strength, high toughness, and excellent fatigue resistance, making it suitable for heavy-duty steel structure applications. The precise composition ratio can avoid impurity segregation and performance dispersion problems, and the regular billet size can ensure the stability of subsequent rolling.

[0075] S2, segmented stepped heating treatment: A three-stage walking beam furnace is used for heating. The preheating stage reaches 700℃ and holds for 28 minutes to slowly release the initial stress of the billet; the heating stage reaches 1000℃ and holds for 48 minutes to rapidly raise the billet temperature to the rolling range; the soaking stage reaches 1200℃ and holds for 32 minutes to ensure uniform overall billet temperature. The excess air coefficient in the furnace is controlled at 1.10, the furnace pressure is stably controlled within ±3Pa, and the overall temperature difference fluctuation of the billet is ≤±4℃, completely avoiding rolling defects and initial stress caused by uneven heating.

[0076] S3, Continuous Constant Tension Precision Rolling: Employing a 10-pass continuous hot rolling process, with an initial rolling temperature of 1170℃ and a final rolling temperature of 920℃, this temperature range yields the best steel plasticity and grain refinement. During the rolling process, the constant tension between stands is controlled at 1200N, with tension fluctuation error ≤±20N. The roll speed is stably controlled at 3.8m / s. After rolling, the angle steel cross-sectional dimension deviation is ≤±0.08mm, and the flange symmetry and web flatness meet high-precision standards. The surface is free of rolling scratches, wrinkles, and indentations.

[0077] S4, Precise Cutting to Length: Online flying shears are used for dynamic cutting to length. The finished product length is set to 9m, the cutting response delay is 0.18s, and the perpendicularity error of the cut end face is 0.25mm. After cutting, the end burrs and flash are removed by automatic grinding equipment to ensure that the end face is flat and stress-free, providing a regular forming structure for uniform cooling in the future.

[0078] S5, Segmented Temperature Controlled Cooling on a Cooling Bed: The high-temperature angle steel after rolling and cutting is fed into an optimized cooling bed and subjected to a three-stage gradient cooling system. The high-temperature rapid cooling section (900℃~700℃) has a cooling rate of 10℃ / s to quickly suppress grain coarsening and remove residual surface heat; the medium-temperature uniform and pressure-stabilized section (700℃~400℃) has a cooling rate of 4.5℃ / s to ensure synchronous phase transformation and temperature uniformity between the angle steel flange and web, with the temperature difference stably controlled within 6℃; the low-temperature shaping and slow cooling section (400℃~room temperature) has a cooling rate of 1.2℃ / s to slowly release internal residual stress and complete the profile shaping.

[0079] Synchronous stepping conveyor and dynamic airflow adjustment: The cooling bed features a synchronous stepping conveyor with a step distance of 120mm, a step interval of 2.2s, and a stable conveying speed of 1.2m / min. The cooling bed has three independent ventilation zones: the high-temperature cooling zone has a fan frequency of 42Hz and a ventilation volume of 6500m³ / h; the medium-temperature uniform temperature zone has a fan frequency of 33Hz and a ventilation volume of 4200m³ / h; and the low-temperature setting zone has a fan frequency of 25Hz and a ventilation volume of 3200m³ / h. During production, two AI calculation models are activated in real time. The AI ​​dynamic airflow calculation model uses parameters K1=0.90, K2=1.28, and K3=0.10, adaptively fine-tuning the airflow based on real-time temperature difference, heat dissipation area, and conveying speed. The AI ​​deformation prediction speed adjustment model uses 1.2m / min as the base speed, monitoring residual stress and deformation deviation in real time, adaptively correcting the conveying speed, and avoiding deformation defects throughout the process.

[0080] S6, Straightening, Finishing, and Warehousing: A 9-roll straightener is used for precise straightening with a straightening pressure of 45kN. After straightening, the straightness error of the angle steel is 0.8mm / m, and the torsion error is 0.4mm / m, fully meeting the high-precision profile standards. Subsequently, surface finishing, dimensional re-inspection, and ultrasonic non-destructive testing are carried out to remove a small number of unqualified products. Finally, the products are sorted, packaged, and stored.

[0081] The production results of this application example are as follows: the overall production cycle is shortened by 22% compared with the traditional process, and the daily output of a single production line is increased by 18%; the metallographic structure of the finished angle steel is uniform and dense, and the grain size uniformity is improved by 35%; the tensile strength is stable at 560MPa~580MPa, the yield strength is stable at 365MPa~380MPa, and the batch dispersion of mechanical properties is ≤3%; the product deformation defect rate is reduced to below 0.3%, and the pass rate is 99.5%; the surface finish of the profile is excellent, with no oxidation, decarburization, or deformation defects, and the dimensional accuracy is greatly improved, fully meeting the requirements of high-strength and high-precision steel structure engineering.

[0082] Application Example 2: High-efficiency production process of Q235B equal angle steel (50mm×50mm×5mm)

[0083] This application example focuses on the large-scale continuous production of Q235B ordinary high-strength equal angle steel (50mm×50mm×5mm) specifically for building envelopes and light steel structures. It is suitable for the needs of large-volume, cost-effective production in civil buildings. The specific production steps and parameters are as follows:

[0084] S1. Raw Material Selection and Pretreatment: Q235B continuously cast steel billets of 150mm × 150mm and 8000mm in length are selected. The billet composition is controlled as follows: carbon content 0.15%, manganese content 1.30%, sulfur content 0.025%, and phosphorus content 0.028%. The low impurity and low carbon-manganese ratio are suitable for the toughness and strength requirements of lightweight angle steel. The billets are shot-blasted and end-face ground, with a surface roughness controlled at 6.0μm and an end-face flatness error of 0.4mm / m, thoroughly removing surface defects and impurities to ensure the basic quality of the billet forming.

[0085] S2, segmented stepped heating treatment: preheating section temperature 680℃, holding time 25min, to achieve low-temperature uniform preheating of the billet; heating section temperature 980℃, heating time 42min, to rapidly heat to the rolling temperature range; soaking section temperature 1190℃, holding time 28min, to ensure uniform temperature of the billet throughout. The excess air coefficient in the furnace is 1.08, the furnace pressure is stably controlled between -2Pa and 2Pa, the billet temperature difference fluctuation is ≤±5℃, and the heating uniformity is good.

[0086] S3, Continuous Constant Tension Precision Rolling: Employing an 8-pass continuous hot rolling process, with an initial rolling temperature of 1160℃ and a final rolling temperature of 910℃, it is suitable for the rapid rolling needs of small angle steel. The rolling constant tension is controlled at 950N, with tension fluctuation ≤±25N, and a roll speed of 4.2m / s, efficiently completing the rolling of small profiles. The finished product cross-sectional dimensional deviation is ≤±0.09mm, resulting in neat formation and precise dimensions.

[0087] S4, Precise Cutting to Length: Online flying shear cutting to length, with a set finished length of 6m, a cutting response delay of 0.15s, an end face perpendicularity error of 0.28mm, automatic grinding to remove end burrs and flash, ensuring that the profile end structure is neat and free of stress concentration defects.

[0088] S5, segmented temperature-controlled cooling bed: High-temperature rapid cooling section with a cooling rate of 9℃ / s, quickly reducing the high-temperature residual heat of the profile and refining the surface grains; Medium-temperature uniform and pressure-stabilizing section with a cooling rate of 4.0℃ / s, precisely controlling the phase transformation process to ensure synchronous cooling of all parts of the profile without phase transformation deviation, and a stable internal and external temperature difference of ≤7℃; Low-temperature shaping and slow cooling section with a cooling rate of 1.0℃ / s, slowly releasing internal residual stress and achieving precise shaping;

[0089] Synchronous stepping conveyor and dynamic airflow adjustment: The cooling bed step distance is 100mm, the step interval is 2.0s, and the stable conveying speed is 1.0m / min. Three-zone ventilation parameters: High-temperature zone fan frequency 40Hz, airflow 6000m³ / h; medium-temperature zone fan frequency 30Hz, airflow 3800m³ / h; low-temperature zone fan frequency 22Hz, airflow 2800m³ / h. The AI ​​dynamic airflow calculation model has correction coefficients K1=0.88, K2=1.25, and K3=0.08, adaptively fine-tuning the airflow based on the small heat dissipation area and fast cooling speed of small angle steel. The AI ​​deformation prediction speed adjustment model uses 1.0m / min as the base speed to predict deformation trends in real time and correct conveying parameters, adapting to the easily deformable production characteristics of small angle steel and completely avoiding bending and twisting defects.

[0090] S6, Straightening, Finishing, and Warehousing: A 7-roll straightener is used for straightening, with a straightening pressure of 38kN, suitable for the straightening needs of small profiles. This avoids excessive pressure that could cause profile deformation. After straightening, the straightness error is 0.9mm / m, and the torsion error is 0.45mm / m. After dimensional re-inspection, surface inspection, and non-destructive testing, unqualified products are rejected, and the products are packaged and stored in batches.

[0091] The production results of this application example are as follows: the overall production cycle is shortened by 18% compared with the traditional process, the stability of continuous production on the production line is greatly improved, and there is no redundancy in the standby process; the metallographic structure of the finished angle steel is uniform, and the residual stress is reduced by more than 40% compared with the traditional process; the tensile strength is stable at 470MPa~490MPa, and the yield strength is stable at 245MPa~260MPa, which fully meets the national standard performance requirements for high-strength angle steel; the product forming qualification rate is 99.3%, the deformation defect rate is less than 0.4%, and the surface quality and dimensional accuracy are excellent. It is suitable for large-scale industrialized continuous production of civil buildings, and the production cost-effectiveness and market competitiveness are significantly improved.

[0092] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A high-efficiency production process and forming method for high-strength angle steel, characterized in that, include: S1, Raw material selection and pretreatment; S2, the pretreated raw material is subjected to segmented step heating treatment; S3, the raw material that has undergone the segmented stepped heating treatment is subjected to continuous constant tension precision rolling; S4, the raw material that has undergone continuous constant tension precision rolling is precisely cut to length. S5 involves integrating optimized segmented temperature control cooling on a cooling bed to cool the raw material after precise cutting to length. S5 employs a segmented gradient temperature control cooling mode, dividing the angle steel cooling process into three stages: a high-temperature rapid cooling stage, a medium-temperature uniform temperature and pressure stabilization stage, and a low-temperature shaping and slow cooling stage. This achieves differentiated cooling rate control across different temperature ranges. The integrated optimized segmented temperature control cooling on the cooling bed, combined with synchronous step-by-step conveying and dynamic airflow adaptive adjustment, includes: based on an AI dynamic airflow calculation model and an AI deformation prediction speed adjustment model, real-time matching of angle steel specifications and cooling status, and adaptive adjustment of conveying and ventilation parameters. S6, the material that has completed the integrated optimized segmented temperature-controlled cooling of the cooling bed is then straightened, finished and put into storage.

2. The efficient production process and forming method of high-strength angle steel according to claim 1, characterized in that, The S1 raw material selection and pretreatment specifically includes: selecting Q235B and Q355B carbon structural steel continuous casting billets as production raw materials, with billet cross-sectional dimensions of 150mm×150mm, 180mm×180mm, and 200mm×200mm, and billet lengths of 6000mm~12000mm; performing surface pretreatment on the selected steel billets, removing oxide scale, rust, and impurities from the billet surface through shot blasting, and simultaneously flattening and grinding the billet end faces to ensure that the billet surface roughness is ≤6.3μm and the end face flatness error is ≤0.5mm / m; when selecting raw materials, priority is given to steel billets with carbon content of 0.12%~0.22%, manganese content of 1.20%~1.60%, sulfur content ≤0.035%, and phosphorus content ≤0.035%.

3. The efficient production process and forming method of high-strength angle steel according to claim 2, characterized in that, The S2 includes: using a three-stage walking beam furnace to heat the steel billet, which is divided into a preheating section, a heating section, and a soaking section; wherein the temperature of the preheating section is controlled at 650℃~750℃, and the preheating holding time is 20min~35min; the temperature of the heating section is controlled at 950℃~1050℃, and the heating time is 40min~55min; the temperature of the soaking section is controlled at 1180℃~1220℃, and the soaking holding time is 25min~40min; the excess air coefficient in the furnace is controlled at 1.05~1.15, and the furnace pressure is maintained at -5Pa~5Pa to ensure uniform heating temperature of the steel billet and temperature difference fluctuation ≤±5℃.

4. The efficient production process and forming method of high-strength angle steel according to claim 3, characterized in that, The S3 includes: employing a multi-pass continuous hot rolling process, with 8 to 12 rolling passes, controlling the initial rolling temperature at 1150℃ to 1190℃, and the final rolling temperature at 900℃ to 950℃; maintaining constant tension between stands during rolling through a tension control system, with a tension control value of 800N to 1500N and a tension fluctuation error ≤ ±30N; adaptively adjusting the roll speed according to the angle steel specifications, with a speed range of 2.5m / s to 5.0m / s, and controlling the rolling dimensional accuracy within ±0.1mm to ensure uniform cross-sectional dimensions and a surface free of rolling scratches and wrinkles after rolling.

5. The efficient production process and forming method of high-strength angle steel according to claim 4, characterized in that, The S4 includes: using a flying shear machine for online dynamic fixed-length cutting, setting the fixed length of the finished angle steel to 6m to 12m according to production needs, with a cutting response delay time ≤0.2s and a cutting end face perpendicularity error ≤0.3mm; after cutting, removing end burrs and flash defects in real time to ensure that the cutting end face is flat and smooth, without stress concentration gaps, providing a basic forming structure for subsequent uniform cooling.

6. The efficient production process and forming method of high-strength angle steel according to claim 5, characterized in that, The integrated optimized segmented temperature-controlled cooling system of the S5 cooling bed specifically includes: a high-temperature rapid cooling section with a temperature range of 700℃ to 900℃ and a cooling rate controlled at 8℃ / s to 12℃ / s; a medium-temperature uniform and pressure-stabilized section with a temperature range of 400℃ to 700℃ and a cooling rate controlled at 3℃ / s to 6℃ / s; and a low-temperature shaping and slow cooling section with a temperature range of room temperature to 400℃ and a cooling rate controlled at 0.5℃ / s to 2℃ / s. The surface and core temperatures of the angle steel are collected in real time throughout the three-stage cooling process to ensure that the temperature difference between the flange and the web of the angle steel is ≤8℃, thereby eliminating deformation stress caused by local temperature differences.

7. The efficient production process and forming method of high-strength angle steel according to claim 6, characterized in that, In the synchronous stepping conveying and dynamic air volume adaptive adjustment of S5, the synchronous stepping conveying adopts an intermittent uniform speed stepping mode with a step distance of 80mm to 150mm, a stepping interval of 1.5s to 3.0s, and a conveying speed stably controlled at 0.8m / min to 1.5m / min; the dynamic air volume adjustment adopts a zoned independent ventilation structure, dividing the cooling bed into three independent ventilation units: a high-temperature cooling zone, a medium-temperature uniform temperature zone, and a low-temperature shaping zone. The frequency adjustment range of the fan in each unit is 20Hz to 50Hz, and the ventilation air volume adjustment range is 3000m³ / h to 8000m³ / h.

8. The efficient production process and forming method of high-strength angle steel according to claim 7, characterized in that, The calculation formula of the AI ​​dynamic air volume calculation model is shown in equation (1): （1）； in, Real-time adaptive ventilation volume, unit m³ / h; The real-time internal and external temperature difference of the angle steel, in °C; The effective heat dissipation surface area of ​​the angle steel, in m²; This refers to the real-time conveying speed of the cooling bed, expressed in m / min. The density of the angle steel is taken as 7.85 g / cm³. The ambient reference temperature is expressed in °C. , , These are adaptive correction coefficients, with values ​​ranging from 0.85 to 0.95, 1.20 to 1.35, and 0.05 to 0.15, respectively.

9. The efficient production process and forming method of high-strength angle steel according to claim 8, characterized in that, The calculation formula for the AI ​​deformation prediction speed regulation model is shown in equation (2): （2）； in, To optimize conveying speed in real time, the unit is m / min; The reference conveying speed is expressed in m / min. This is the real-time deformation deviation coefficient, with a value ranging from 0 to 0.2; This represents the real-time residual stress value of the angle steel, in MPa. The residual stress threshold allowed by the standard for angle steel is 120 MPa.

10. The efficient production process and forming method of high-strength angle steel according to claim 9, characterized in that, S7 includes: feeding angle steel cooled to room temperature into a multi-roll straightener for overall straightening, with the number of straightening rolls set to 7 to 11 rolls, and the straightening pressure controlled at 30kN to 60kN. After straightening, the straightness error of the angle steel is ≤1.0mm / m, and the torsion error is ≤0.5mm / m. After straightening, surface finishing, dimensional re-inspection, and non-destructive testing are carried out. Unqualified products with excessive dimensions, surface defects, and internal cracks are removed, and finally, they are classified, packaged, and stored. The overall production process cycle time is shortened by 15% to 25% compared with the traditional process, and the product mechanical property qualification rate is ≥99.2%.

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