A method, system and storage medium for improving the quality of a cast strand by electromagnetic stirring

Abstract

The application discloses a method, system and storage medium for improving the quality of a casting blank through electromagnetic stirring. The method comprises the following steps: S1, detecting the equiaxed crystal ratio and the composition distribution of the produced casting blank; S2, judging whether the equiaxed crystal ratio reaches the first preset requirement and whether the composition distribution reaches the second preset requirement, if the equiaxed crystal ratio does not reach the first preset requirement or / and the composition distribution does not reach the second preset requirement, then analyzing to obtain an abnormal classification; S3, according to the abnormal classification, corresponding adjustment strategies are carried out; S4, the produced casting blank after the adjustment strategies is detected, whether the equiaxed crystal ratio and the composition distribution reach the preset requirement is judged: if not, then returning to step S2. The application adopts corresponding adjustment strategies for different abnormal classifications, adjusts the current and frequency parameters of the box-type electromagnetic stirrer and the roller-type electromagnetic stirrer, fully gives play to the synergistic effect of the two stirrers, and realizes the feedback and dynamic parameter adjustment of the casting blank quality.

Description

Technical Field

[0001] This invention relates to the field of steel production technology, and in particular to a method, system, and storage medium for improving the quality of cast billets through electromagnetic stirring. Background Technology

[0002] Continuous casting is one of the most widely used processes in modern steel production. The quality of the cast billet directly determines the mechanical properties, processing performance, and service life of the subsequently rolled products. Among these, equiaxed crystal ratio and uniformity of composition distribution are core indicators for evaluating the internal quality of the cast billet. Insufficient equiaxed crystal ratio can lead to defects such as well-developed columnar crystals, central porosity, and cracks within the cast billet. Uneven composition distribution (i.e., macroscopic segregation) can cause differences in chemical composition and properties in different regions of the cast billet, seriously affecting the overall reliability of the steel, especially restricting the production of high-end steel and making it difficult to meet the stringent requirements of high-quality and special steels in energy, transportation, and intelligent manufacturing. To improve the equiaxed crystal ratio and composition distribution of the cast billet, electromagnetic stirring technology, as a non-contact and pollution-free metallurgical control method, is widely used in continuous casting production. Its core principle is to drive the flow of molten steel through electromagnetic force, breaking up the columnar crystals formed during solidification, promoting an increase in nucleation centers to improve the equiaxed crystal ratio, and simultaneously stirring the pasty region at the end of solidification to promote the uniform distribution of solute elements and reduce macroscopic segregation. However, most existing electromagnetic stirring billet production processes use fixed electromagnetic stirring parameters for continuous production, lacking feedback mechanisms for billet quality and dynamic parameter adjustment mechanisms. Summary of the Invention

[0003] The present invention aims to at least solve one of the technical problems existing in the prior art. To this end, the present invention proposes a method, system, and storage medium for improving the quality of cast billets through electromagnetic stirring.

[0004] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A method for improving the quality of cast billets by electromagnetic stirring includes the following steps: S1, detecting the equiaxed crystal ratio and composition distribution of the produced cast billets; S2, determining whether the equiaxed crystal ratio meets a first preset requirement and whether the composition distribution meets a second preset requirement; if the equiaxed crystal ratio and composition distribution meet the first and second preset requirements respectively, then maintaining the current parameters for continuous production; if the equiaxed crystal ratio does not meet the first preset requirement and / or the composition distribution does not meet the second preset requirement, then analyzing and obtaining an anomaly classification; S3, according to the anomaly classification, implementing a corresponding adjustment strategy, the adjustment strategy including at least one of adjusting the current of the box-type electromagnetic stirrer, adjusting the frequency of the box-type electromagnetic stirrer, adjusting the current of the roller-type electromagnetic stirrer, and adjusting the frequency of the roller-type electromagnetic stirrer; the box-type electromagnetic stirrer is installed on the periphery of the billet exit section at the bottom of the crystallizer; the roller-type electromagnetic stirrer is used to guide the cast billets output from the billet exit section; S4, detecting the cast billets produced after implementing the adjustment strategy to obtain the equiaxed crystal ratio and composition distribution of the cast billets, and determining whether the equiaxed crystal ratio and composition distribution meet the preset requirements: if yes, then maintaining the current parameters for continuous production; if no, then returning to step S2.

[0005] Further, the equiaxed crystal ratio includes the equiaxed crystal ratio and the proportion of columnar crystals in the billet; the analysis to obtain the anomaly classification specifically includes: obtaining the proportion of columnar crystals, and determining whether the proportion of columnar crystals in the billet meets a third preset requirement; if the composition distribution meets a second preset requirement but the proportion of columnar crystals in the billet does not meet a third preset requirement, then the anomaly is classified as a first anomaly; if the composition distribution does not meet a second preset requirement but the proportion of columnar crystals in the billet meets a third preset requirement, then the anomaly is classified as a second anomaly; if the composition distribution meets a second preset requirement and the proportion of columnar crystals in the billet meets a third preset requirement, then the anomaly is classified as a third anomaly; if the composition distribution does not meet a second preset requirement and the proportion of columnar crystals in the billet does not meet a third preset requirement, then the anomaly is classified as a fourth anomaly.

[0006] Furthermore, the adjustment strategy includes a first adjustment strategy, a second adjustment strategy, a third adjustment strategy, and a fourth adjustment strategy, respectively corresponding to the first abnormality, the second abnormality, the third abnormality, and the fourth abnormality; the first adjustment strategy includes increasing the current of the box-type electromagnetic stirrer and increasing the current of the roller-type electromagnetic stirrer; the second adjustment strategy includes increasing the current of the box-type electromagnetic stirrer, increasing the frequency of the box-type electromagnetic stirrer, and increasing the current of the roller-type electromagnetic stirrer; the third adjustment strategy includes increasing or maintaining the current of the box-type electromagnetic stirrer, decreasing the frequency of the box-type electromagnetic stirrer, and increasing the current of the roller-type electromagnetic stirrer; the fourth adjustment strategy includes increasing the current of the box-type electromagnetic stirrer, increasing the frequency of the box-type electromagnetic stirrer, and increasing the current of the roller-type electromagnetic stirrer.

[0007] Furthermore, the roller electromagnetic stirrer is provided in three groups: a near roller stirrer, a middle roller stirrer, and a far roller stirrer; the near roller stirrer, the middle roller stirrer, and the far roller stirrer are distributed sequentially in the direction away from the crystallizer and are spaced apart along the extension direction of the billet.

[0008] Furthermore, the first anomaly, the second anomaly, the third anomaly, and the fourth anomaly each have multiple levels, and the first regulation strategy, the second regulation strategy, the third regulation strategy, and the fourth regulation strategy each have multiple levels of regulation strategies corresponding to the first anomaly, the second anomaly, the third anomaly, and the fourth anomaly, respectively.

[0009] Furthermore, the reference for adjusting the values ​​of each parameter in the first, second, third, and fourth adjustment strategies is the reference value of each parameter, which is determined based on the current process parameters.

[0010] Further, the third preset requirement is that the proportion of columnar crystals ΔG is less than 50%; the multiple levels of the first anomaly are divided as follows: when 50%≤ΔG≤55%, it is the first mild anomaly level of the first anomaly, and the corresponding first mild adjustment strategy of the first adjustment strategy is: the current of the box-type electromagnetic stirrer is increased by a first preset adjustment value based on the first reference current, the current of the near-roller stirrer is increased by a second preset adjustment value based on the second reference current; the current of the middle roller stirrer is increased by a third preset adjustment value based on the third reference current; when 55<ΔG≤60%, it is the first moderate anomaly level of the first anomaly, and the corresponding first moderate adjustment strategy of the first adjustment strategy is: the current of the box-type electromagnetic stirrer is increased by a fourth preset adjustment value based on the first reference current, and the frequency is increased by a fifth preset adjustment value based on the first reference frequency; the current of the near-roller stirrer is increased by a sixth preset adjustment value based on the second reference current, and the frequency is increased by a seventh preset adjustment value based on the second reference frequency; the middle roller stirrer... The current of the box-type electromagnetic stirrer is increased by an eighth preset adjustment value based on the third reference current, and the frequency is increased by a ninth preset adjustment value based on the third reference frequency; the current of the far roller stirrer is increased by a tenth preset adjustment value based on the fourth reference current; when ΔG>60%, it is the first severe abnormality level of the first abnormality, and the corresponding first severe adjustment strategy of the first adjustment strategy is as follows: the current of the box-type electromagnetic stirrer is increased by an eleventh preset adjustment value based on the first reference current, and the frequency is increased by a twelfth preset adjustment value based on the first reference frequency; the current of the near roller stirrer is increased by a thirteenth preset adjustment value based on the second reference current, and the frequency is increased by a fourteenth preset adjustment value based on the second reference frequency; the current of the middle roller stirrer is increased by a fifteenth preset adjustment value based on the third reference current, and the frequency is increased by a sixteenth preset adjustment value based on the third reference frequency; the current of the far roller stirrer is increased by a seventeenth preset adjustment value based on the fourth reference current, and the frequency is decreased by an eighteenth preset adjustment value based on the fourth reference frequency.

[0011] Furthermore, before the return step S2, all preset adjustment values ​​are increased by their respective preset growth values.

[0012] This invention also provides a system for improving the quality of cast billets through electromagnetic stirring, comprising: a detection module for detecting the equiaxed crystal ratio and composition distribution of the produced cast billets; a judgment and analysis module for judging whether the equiaxed crystal ratio meets a first preset requirement and whether the composition distribution meets a second preset requirement; if the equiaxed crystal ratio and composition distribution meet the first and second preset requirements respectively, then production is maintained with the current parameters; if the equiaxed crystal ratio does not meet the first preset requirement and / or the composition distribution does not meet the second preset requirement, then an anomaly classification is obtained through analysis; and an adjustment module for implementing corresponding adjustment strategies based on the anomaly classification. The adjustment strategy includes at least one of adjusting the current of the box-type electromagnetic stirrer, adjusting the frequency of the box-type electromagnetic stirrer, adjusting the current of the roller-type electromagnetic stirrer, and adjusting the frequency of the roller-type electromagnetic stirrer; the box-type electromagnetic stirrer is installed on the periphery of the billet exit section at the bottom of the crystallizer; the roller-type electromagnetic stirrer is used to guide the billet output from the billet exit section; the detection feedback module is used to detect the billet produced after the adjustment strategy, obtain the equiaxed crystal ratio and composition distribution of the billet, and determine whether the equiaxed crystal ratio and composition distribution meet the preset requirements: if yes, the current parameters are maintained and production continues; if no, the analysis module and the adjustment module are to repeat their work.

[0013] The present invention also provides a storage medium storing a computer program that, when executed by a processor, implements a method for improving the quality of cast billets through electromagnetic stirring.

[0014] The present invention has the following beneficial effects: Step S1 detects the equiaxed crystal ratio and composition distribution of the cast billet, providing accurate data support for subsequent control. Step S2 determines whether the quality indicators meet the standards, clarifies the control requirements, and classifies abnormal situations, avoiding the problem of blind parameter adjustment in existing technologies. Step S3 adopts corresponding adjustment strategies for different abnormality classifications, adjusting the current and frequency parameters of the box-type electromagnetic stirrer and / or roller-type electromagnetic stirrer to fully utilize the synergistic effect of the two stirrers. The adjustment of the parameters of both can effectively break up columnar crystals, promote nucleation, and reduce macroscopic segregation, ultimately achieving stable equiaxed crystal ratio and composition distribution uniformity of the cast billet to meet the preset requirements, reducing defects such as well-developed columnar crystals, central porosity, cracks, and compositional segregation, improving the overall reliability of the cast billet, realizing feedback on the quality of the cast billet and dynamic parameter adjustment, and can automatically adjust parameters, instead of relying on manual setting and adjustment based on human experience, resulting in high adjustment efficiency.

[0015] In addition to the objectives, features, and advantages described above, the present invention has other objectives, features, and advantages. The invention will now be described in further detail with reference to the figures. Attached Figure Description

[0016] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings: Figure 1 This is a schematic diagram of the overall process of the present invention; Figure 2 This is a schematic diagram of the overall structural layout of the present invention.

[0017] Legend: Crystallizer 100; Box-type electromagnetic stirrer 200; Near roller agitator 300, medium roller agitator 310, far roller agitator 320; The billet is 400mm and the liquid core is 410mm. Detailed Implementation

[0018] It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0020] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0021] Furthermore, the use of terms such as "first" and "second" in this invention is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. Additionally, the technical solutions of the various embodiments can be combined with each other, but only on the basis of being achievable by those skilled in the art. When the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed by this invention.

[0022] Please refer to Figure 1 and Figure 2 A preferred embodiment of the present invention provides a method for improving the quality of a cast billet by electromagnetic stirring, comprising steps S1, S2, S3, and S4.

[0023] S1 detects the equiaxed crystal ratio and compositional distribution of the produced 400mm cast billet. This can be done manually using instruments or through image recognition analysis.

[0024] S2, determine whether the equiaxed crystal ratio meets the first preset requirement and whether the composition distribution meets the second preset requirement. If the equiaxed crystal ratio and composition distribution meet the first and second preset requirements respectively, then maintain the current parameters and continue production. If the equiaxed crystal ratio does not meet the first preset requirement and / or the composition distribution does not meet the second preset requirement, then analyze and obtain an anomaly classification. In this embodiment, the first preset requirement is an equiaxed crystal ratio η ≥ 65%.

[0025] S3. Based on the anomaly classification, implement the corresponding adjustment strategy. The adjustment strategy includes at least one of adjusting the current of the box-type electromagnetic stirrer, adjusting the frequency of the box-type electromagnetic stirrer, adjusting the current of the roller-type electromagnetic stirrer, and adjusting the frequency of the roller-type electromagnetic stirrer. The box-type electromagnetic stirrer is set in the zero-segment region of molten steel solidification, i.e., the initial solidification stage. The box-type electromagnetic stirrer 200 is installed at the bottom of the crystallizer 100. The roller-type electromagnetic stirrer is used to guide the billet output from the crystallizer 100.

[0026] S4. Inspect the billet produced after the adjustment strategy to obtain the equiaxed crystal ratio and composition distribution of the billet, and determine whether the equiaxed crystal ratio and composition distribution meet the preset requirements: if yes, maintain the current parameters and continue production; if no, return to step S2.

[0027] This invention detects the equiaxed crystal ratio and composition distribution of the cast billet in step S1, providing precise data support for subsequent control. Step S2 determines whether the quality indicators meet the standards, clarifies the control requirements, and classifies abnormal situations, avoiding the problem of blind parameter adjustment in existing technologies. Step S3 adopts corresponding adjustment strategies for different abnormal classifications, adjusting the current and frequency parameters of the box-type electromagnetic stirrer and / or roller-type electromagnetic stirrer to fully leverage the synergistic effect of the two stirrers. The box-type electromagnetic stirrer can specifically optimize the surface and near-surface quality of the cast billet and eliminate superheat in molten steel, while the roller-type electromagnetic stirrer can continuously optimize the internal structure and composition distribution of the cast billet. The adjustment of the parameters of both can effectively break up columnar crystals, promote nucleation, and reduce macroscopic segregation, ultimately achieving stable equiaxed crystal ratio and composition distribution uniformity of the cast billet to meet preset requirements, reducing defects such as well-developed columnar crystals, central porosity, cracks, and compositional segregation, and improving the overall reliability of the cast billet.

[0028] In some embodiments of the present invention, the analysis to obtain anomaly classification specifically includes: detecting and obtaining the proportion of columnar crystals, and determining whether the proportion of columnar crystals in the billet meets a third preset requirement; if the composition distribution meets a second preset requirement but the proportion of columnar crystals in the billet does not meet the third preset requirement, then the anomaly is classified as a first anomaly; if the composition distribution does not meet the second preset requirement but the proportion of columnar crystals in the billet meets the third preset requirement, then the anomaly is classified as a second anomaly; if the composition distribution meets the second preset requirement and the proportion of columnar crystals in the billet meets the third preset requirement, then the anomaly is classified as a third anomaly; if the composition distribution does not meet the second preset requirement and the proportion of columnar crystals in the billet does not meet the third preset requirement, then the anomaly is classified as a fourth anomaly.

[0029] Specifically, the third preset requirement is that the proportion of columnar crystals ΔG is less than 50%, and a proportion greater than or equal to 50% is considered abnormal; the second preset requirement is that the absolute value of the deviation between the actual composition of the specified metal element and the standard design composition of the steel grade ΔC is less than or equal to 5%. Usually, it is calculated separately for each element, and the maximum value is taken for judgment. The core metal element of concern is taken as the specified metal element. For example, for silicon steel, Si and Mn are the core alloying elements of silicon steel. Both need to be tested and calculated. If either element exceeds the standard, the composition is judged to be abnormal.

[0030] This method precisely categorizes billet quality anomalies into four types, overcoming the shortcomings of existing technologies that only broadly assess substandard quality without pinpointing specific anomalies. By using compositional distribution and columnar crystal ratio as dual judgment dimensions, it achieves accurate attribution of billet quality anomalies, providing clear and quantifiable judgment criteria for subsequent targeted adjustment strategies. This avoids ineffective regulation due to mismatch between adjustment strategies and anomalies, making the adjustment of electromagnetic stirring parameters more targeted and improving the accuracy and effectiveness of regulation.

[0031] In some embodiments of the present invention, the adjustment strategy includes a first adjustment strategy, a second adjustment strategy, a third adjustment strategy, and a fourth adjustment strategy, respectively corresponding to the first abnormality, the second abnormality, the third abnormality, and the fourth abnormality.

[0032] The first adjustment strategy includes increasing the current of the box-type electromagnetic stirrer and increasing the current of the roller-type electromagnetic stirrer. The second adjustment strategy includes increasing the current of the box-type electromagnetic stirrer, increasing the frequency of the box-type electromagnetic stirrer, and increasing the current of the roller-type electromagnetic stirrer. The third adjustment strategy includes increasing or maintaining the current of the box-type electromagnetic stirrer, decreasing the frequency of the box-type electromagnetic stirrer, and increasing the current of the roller-type electromagnetic stirrer. The fourth adjustment strategy includes increasing the current of the box-type electromagnetic stirrer, increasing the frequency of the box-type electromagnetic stirrer, and increasing the current of the roller-type electromagnetic stirrer. These four anomaly classifications are matched with corresponding specific adjustment strategies, achieving precise adaptation between anomalies and control methods, and solving the problems of unclear rules for stirrer parameter adjustment and blind combinations of current and frequency in existing technologies. To address the causes and effects of different anomalies, the current and frequency adjustments of the box-type and roller-type electromagnetic stirrers are combined in a differentiated manner. For example, for the first anomaly, the current is increased only in a targeted manner; for the second and fourth anomalies, the current and frequency are increased in all dimensions; and for the third anomaly, the current and frequency of the box-type stirrer are adjusted in a differentiated manner. This approach fully leverages the synergistic effect of the box-type stirrer in optimizing the near-surface quality of the billet and the roller-type stirrer in optimizing the internal structure, while avoiding energy waste and new billet quality problems caused by excessive parameter adjustment.

[0033] like Figure 2 As shown, in some embodiments of the present invention, the roller electromagnetic stirrer is provided in three groups: a near roller stirrer 300, a middle roller stirrer 310, and a far roller stirrer 320. The near roller stirrer 300, the middle roller stirrer 310, and the far roller stirrer 320 are distributed sequentially in the direction away from the crystallizer 100 and spaced apart along the billet extension direction. That is, the near roller stirrer 300, the middle roller stirrer 310, and the far roller stirrer 320 are respectively distributed at the near downstream section of the crystallizer, the middle solidification stage of the billet liquid core 410, and the end solidification stage of the billet liquid core. By refining the roller electromagnetic stirrer into three groups of near roller stirrers 300, middle roller stirrers 310, and far roller stirrers 320 spaced apart along the billet extension direction, it adapts to the quality control requirements of different solidification stages after the billet exits the crystallizer 100, and solves the defect that the stirring range of a single roller stirrer is limited and cannot perform fine control of the entire solidification process of the billet. The near-roller agitator 300 can immediately agitate the billet that has just exited the crystallizer 100, while the middle-roller agitator 310 and the far-roller agitator 320 continuously apply agitation to the billet during the subsequent solidification stage. This achieves segmented and progressive electromagnetic agitation throughout the entire solidification process of the billet, making the agitation more closely match the solidification state at different locations of the billet and effectively improving the equiaxed crystal ratio and compositional homogenization. At the same time, the spaced distribution design of the three sets of roller agitators allows for targeted adjustment of one or more sets of parameters according to abnormal billet quality conditions, further enhancing the flexibility and precision of agitation parameter adjustment.

[0034] It is understood that in some other embodiments, the number and arrangement of roller electromagnetic stirrers can be selectively set according to process requirements and core length. For example, in some other embodiments, only one set of near roller stirrers 300 and one set of far roller stirrers 320 can be set.

[0035] The core function of the near-roller agitator 300 is to suppress the preferential growth of columnar crystals and achieve initial solute diffusion. The medium-roller agitator 310 corresponds to the core region in the middle stage of billet solidification, where the liquid core solidifies the fastest and is at the critical stage of equiaxed crystal nucleation, resulting in the most severe solute enrichment. Its core function is to promote nucleation core proliferation and achieve homogenization of the solute throughout the entire region. The far-roller agitator 320 corresponds to the fine-grained region in the late stage of billet solidification, where the liquid core gradually shrinks and crystal nuclei enter the growth stage. Local minor deviations in composition are prone to occur. Its core function is to assist in the uniform growth of crystal nuclei and achieve final minor adjustments in composition.

[0036] In a specific embodiment of the present invention, the first abnormality, the second abnormality, the third abnormality and the fourth abnormality each have multiple levels. The first adjustment strategy, the second adjustment strategy, the third adjustment strategy and the fourth adjustment strategy correspond to the first abnormality, the second abnormality, the third abnormality and the fourth abnormality having multiple levels of adjustment strategies, that is, each level of abnormality will correspond to a level of adjustment strategy. In this embodiment, the first anomaly has three levels: a first mild anomaly, a first moderate anomaly, and a first severe anomaly; the first adjustment strategy has a first mild adjustment strategy corresponding to the first mild anomaly, a first moderate adjustment strategy corresponding to the first moderate anomaly, and a first severe adjustment strategy corresponding to the first severe anomaly; the second anomaly includes three levels: a second mild anomaly, a second moderate anomaly, and a second severe anomaly; the second adjustment strategy has three levels: a second mild adjustment strategy corresponding to the second mild anomaly, a second moderate adjustment strategy corresponding to the second moderate anomaly, and a second severe adjustment strategy corresponding to the second severe anomaly; the third anomaly has three levels: a third mild anomaly, a third moderate anomaly, and a third severe anomaly; the third adjustment strategy has a third mild adjustment strategy corresponding to the third mild anomaly, a third moderate adjustment strategy corresponding to the third moderate anomaly, and a third severe adjustment strategy corresponding to the third severe anomaly; the fourth anomaly has three levels: a fourth mild anomaly, a fourth moderate anomaly, and a fourth severe anomaly; the fourth adjustment strategy has a fourth mild adjustment strategy corresponding to the fourth mild anomaly, a fourth moderate adjustment strategy corresponding to the fourth moderate anomaly, and a fourth severe adjustment strategy corresponding to the fourth severe anomaly.

[0037] By classifying four types of anomalies into multiple levels and matching corresponding adjustment strategies, graded control of billet quality anomalies is achieved, solving the problem of inaccurate parameter adjustment caused by using a single fixed adjustment method for anomalies of different severity in existing technologies. The strength of the adjustment strategy is designed differently according to the severity of the anomaly, ensuring that the adjustment range of the parameters of the box-type electromagnetic stirrer 200, near-roller stirrer 300, medium-roller stirrer 310, and far-roller stirrer 320 matches the severity of the anomaly. This ensures that severe anomalies are effectively controlled while avoiding problems such as excessive stirring force and new defects on the billet surface caused by over-adjustment of parameters for mild anomalies. This achieves refined and gradient adjustment of electromagnetic stirring parameters. Simultaneously, the graded control rules enhance process adaptability, enabling the handling of different degrees of quality fluctuations caused by changes in raw materials and equipment operating conditions during production, thus improving process stability.

[0038] In some embodiments of the present invention, the reference for adjusting the values ​​of each parameter (current and frequency of the box-type electromagnetic stirrer and the three sets of roller stirrers) in the first, second, third, and fourth adjustment strategies is the reference value of each parameter, which is determined according to the current process parameters. Clearly defining the reference for stirrer parameter adjustment as the reference value determined by the current process parameters solves the shortcomings of existing technologies where parameter adjustment lacks a unified reference and fixed values ​​cannot adapt to different production processes. By using the current process parameters as a reference for relative adjustment of the box-type electromagnetic stirrer 200, the near-roller stirrer 300, the middle-roller stirrer 310, and the far-roller stirrer 320, the adjustment strategy can adapt to the production needs of different steel grades, different billet specifications, and different production conditions, avoiding the problem of fixed-value parameter adjustment failing after process changes, and significantly improving the process adaptability and versatility of the method of the present invention. Simultaneously, since the parameter reference value is determined by the current process parameters, real-time dynamic updates of the parameter adjustment reference can be achieved, ensuring that the adjustment strategy always matches the current production state, further guaranteeing the accuracy and effectiveness of control. For example, in one embodiment, the current process parameters include steel type, billet cross-sectional dimensions, casting speed, superheat, and secondary cooling strength. The parameter reference values ​​(current and frequency of box-type electromagnetic stirrer and three-roller stirrer) of each combination of process parameters can be manually set. For example, in this embodiment, the process parameters are as follows: the steel type is medium grade non-oriented silicon steel W600, the billet cross-sectional dimensions are: thickness 200mm~250mm, width 1000mm~1300mm, casting speed: 1.0m / min~1.2m / min, molten steel superheat: 20℃~25℃, secondary cooling water ratio (secondary cooling strength): 0.30L / kg~0.40L / kg, and the corresponding reference values ​​for each parameter are: the first reference current of the box-type electromagnetic stirrer 200 is 400A, and the first reference frequency is 3HZ; the second reference current of the near-roller stirrer 300 is 300A, and the second reference frequency is 4.5HZ; the third reference current of the middle-roller stirrer 310 is 350A, and the third reference frequency is 4HZ; and the fourth reference current of the far-roller stirrer 320 is 400A, and the fourth reference frequency is 3.5HZ.

[0039] It is understandable that both box-type electromagnetic stirrers and roller stirrers have their own limited parameter adjustment ranges. For example, the parameters of box-type electromagnetic stirrers are limited to 400-1000A / 1.0-6.0Hz, and the parameters of roller stirrers are limited to 200-500A / 1.0-6.0Hz. When the adjusted parameter value exceeds the limited range, the endpoint value of the closest limited range is taken.

[0040] In a specific embodiment of the present invention, the third preset requirement is that the proportion of columnar crystals ΔG is less than 50%; the core reason for the first anomaly is the excessive growth of columnar crystals in the molten steel in the region corresponding to the box-type electromagnetic stirrer 200 and the region corresponding to the near-roller stirrer 300, which squeezes the nucleation space of equiaxed crystals. The adjustment principle is that the box-type electromagnetic stirrer 200 is the main adjustment object, and the adjustment amount of the near-roller stirrer 300, the middle roller stirrer 310, and the far roller stirrer 320 decreases in sequence.

[0041] The first abnormality has multiple levels, which are divided as follows: When 50%≤ΔG≤55%, it is the first mild anomaly level of the first anomaly. The corresponding first mild adjustment strategy is as follows: the current of the box-type electromagnetic stirrer is increased by a first preset adjustment value based on the first reference current; the current of the near-roller stirrer 300 is increased by a second preset adjustment value based on the second reference current; and the current of the middle roller stirrer 310 is increased by a third preset adjustment value based on the third reference current. The box-type electromagnetic stirrer and the near-roller stirrer 300 are the main adjustment targets. In this embodiment, the first preset adjustment value is 50A, the second preset adjustment value is 20A, and the third preset adjustment value is 10A. The increase in the current of the box-type electromagnetic stirrer achieves slight melting of the zero-segment dendrites; the small increase in the near-roller stirrer 300 suppresses the growth of columnar crystals in the coarse-grained region; the slight increase in the middle roller stirrer 310 forms a stirring relay; and the absence of an increase in R3 avoids unnecessary disturbance to the initial crystal nuclei.

[0042] When 55 < ΔG ≤ 60%, it represents the first moderate level of the first anomaly. The corresponding first moderate adjustment strategy is as follows: the current of the box-type electromagnetic stirrer is increased by a fourth preset adjustment value based on the first reference current, and the frequency is increased by a fifth preset adjustment value based on the first reference frequency; the current of the near-roller stirrer 300 is increased by a sixth preset adjustment value based on the second reference current, and the frequency is increased by a seventh preset adjustment value based on the second reference frequency; the current of the middle-roller stirrer 310 is increased by an eighth preset adjustment value based on the third reference current, and the frequency is increased by a ninth preset adjustment value based on the third reference frequency; the current of the far-roller stirrer 320 is increased by a tenth preset adjustment value based on the fourth reference current. In this embodiment, the fourth preset adjustment value is 70A, the fifth preset adjustment value is 0.5Hz, the sixth preset adjustment value is 40A, the seventh preset adjustment value is 0.5Hz, the eighth preset adjustment value is 30A, the ninth preset adjustment value is 0.5Hz, and the tenth preset adjustment value is 10A. The box-type electromagnetic stirrer incrementally enhances zero-segment stirring, the near-roller stirrer 300 significantly increases stirring volume to strongly suppress columnar crystals in the coarse crystal zone, the medium-roller stirrer 310 synchronously increases stirring volume to expand stirring coverage, and the far-roller stirrer 320 slightly increases stirring volume to assist in the initial dispersion of crystal nuclei, making it suitable for moderate columnar crystal over-standard.

[0043] When ΔG > 60%, it represents the first severe level of the first anomaly. The corresponding first severe adjustment strategy is as follows: the current of the box-type electromagnetic stirrer is increased by an eleventh preset adjustment value based on the first reference current, and the frequency is increased by a twelfth preset adjustment value based on the first reference frequency; the current of the near-roller stirrer 300 is increased by a thirteenth preset adjustment value based on the second reference current, and the frequency is increased by a fourteenth preset adjustment value based on the second reference frequency; the current of the middle roller stirrer 310 is increased by a fifteenth preset adjustment value based on the third reference current, and the frequency is increased by a sixteenth preset adjustment value based on the third reference frequency; the current of the far-roller stirrer 320 is increased by a seventeenth preset adjustment value based on the fourth reference current, and the frequency is decreased by an eighteenth preset adjustment value based on the fourth reference frequency. In this embodiment, the eleventh preset adjustment value is 100A, the twelfth preset adjustment value is 0.5Hz, the thirteenth preset adjustment value is 60A, the fourteenth preset adjustment value is 0.5Hz, the fifteenth preset adjustment value is 40A, the sixteenth preset adjustment value is 0.5Hz, the seventeenth preset adjustment value is 20A, and the eighteenth preset adjustment value is 0.5Hz. The box-type electromagnetic stirrer significantly increases the volume to achieve severe dendrite melting at the zero stage. The near-roller stirrer 300 / medium-roller stirrer 310 significantly increases the volume to form a strong stirring band, which completely suppresses columnar crystals. The far-roller stirrer 320 increases the volume synchronously to ensure that the melted dendrites are evenly dispersed to the end of solidification.

[0044] Using a columnar crystal ratio of 50% as the core threshold, the first anomaly is specifically classified into mild, moderate, and severe levels. For each level, specific current and frequency adjustment methods are matched with a box-type electromagnetic stirrer 200 and near-roller stirrer 300, medium-roller stirrer 310, and far-roller stirrer 320. This quantifies the anomaly classification and concretizes the adjustment strategy, solving the problem of lacking specific quantitative standards and implementation feasibility in graded control. By clearly defining numerical thresholds to classify anomaly levels, anomaly judgment becomes quantifiable. Simultaneously, precise adjustment combinations of current and frequency for each stirrer are designed for each level. Mild anomalies only require adjustment of some stirrer currents, while moderate and severe anomalies gradually increase the adjustment dimensions and amplitude, making the adjustment strategy highly operable. The far-roller stirrer 320 is gradually activated for different anomaly levels to achieve a gradient enhancement of the stirring effect, allowing the columnar crystal ratio in the cast billet to be efficiently and steadily reduced below the preset requirements.

[0045] The second anomaly is primarily due to solute enrichment during solidification in the liquid core regions of the box-type electromagnetic stirrer 200, near-roller stirrer 300, and middle-roller stirrer 310, resulting in insufficient mass transfer capacity and compositional segregation. The adjustment principle is that the box-type electromagnetic stirrer 200, near-roller stirrer 300, and middle-roller stirrer 310 serve as the core areas for solute homogenization, employing a larger increment to form a dual-core stirring zone of initial diffusion in the near section and full-range mixing in the middle section; the far-roller stirrer 320 enables fine-tuning of composition at the end of solidification.

[0046] The multiple levels of the second abnormality and their corresponding regulation strategies are classified as follows: When 5% < ΔC ≤ 7%, it is the second mild abnormality level of the second abnormality. The corresponding second mild adjustment strategy is as follows: the current of the box-type electromagnetic stirrer is increased by the nineteenth preset adjustment value (50A in this embodiment) based on the first reference current, and the frequency is increased by the twentieth preset adjustment value (0.2Hz in this embodiment) based on the first reference frequency; the current of the near roller stirrer is increased by the twenty-first preset adjustment value (40A in this embodiment) based on the second reference current, and the frequency is increased by the twenty-second preset adjustment value (0.2Hz in this embodiment) based on the second reference frequency; the current of the middle roller stirrer is increased by the twenty-third preset adjustment value (40A in this embodiment) based on the third reference current, and the frequency is increased by the twenty-fourth preset adjustment value (0.2Hz in this embodiment) based on the third reference frequency; the current of the far roller stirrer is increased by the twenty-fifth preset adjustment value (20A in this embodiment) based on the fourth reference current. The box-type electromagnetic stirrer achieves initial mixing of the solute in the zero stage with small increments, while the near roller stirrer 300 and the medium roller stirrer 310 increase their increments simultaneously to form a gentle, full-area circulating flow field, achieving slight diffusion of the solute. The far roller stirrer 320 makes slight increments to fine-tune the final composition.

[0047] When 7% < ΔC ≤ 9%, it is the second moderate level of the second anomaly. The corresponding second moderate adjustment strategy is as follows: the current of the box-type electromagnetic stirrer is increased by the twenty-sixth preset adjustment value (70A) based on the first reference current, and the frequency is increased by the twenty-seventh preset adjustment value (0.5Hz) based on the first reference frequency; the current of the near roller stirrer is increased by the twenty-eighth preset adjustment value (60A) based on the second reference current, and the frequency is increased by the twenty-ninth preset adjustment value (0.5Hz) based on the second reference frequency; the current of the middle roller stirrer is increased by the thirtieth preset adjustment value (60A) based on the third reference current, and the frequency is increased by the thirty-first preset adjustment value (0.5Hz) based on the third reference frequency; the current of the far roller stirrer is increased by the thirty-second preset adjustment value (40A) based on the fourth reference current, and the frequency is decreased by the thirty-third preset adjustment value (0.5Hz) based on the fourth reference frequency. The box-type electromagnetic stirrer incrementally enhances zero-stage mixing, while the near-roller stirrer 300 and the medium-roller stirrer 310 significantly increase the turbulence of the flow field, enabling rapid mass transfer of solute and global mixing. The far-roller stirrer 320 simultaneously incrementally enhances the uniformity of the final composition, making it suitable for moderate segregation.

[0048] When ΔC > 9%, it is the second severe level of the second anomaly. The corresponding second severe adjustment strategy is as follows: the current of the box-type electromagnetic stirrer is increased by the thirty-fourth preset adjustment value (100A) based on the first reference current, and the frequency is increased by the thirty-fifth preset adjustment value (0.5Hz) based on the first reference frequency; the current of the near roller stirrer is increased by the thirty-sixth preset adjustment value (80A) based on the second reference current, and the frequency is increased by the thirty-seventh preset adjustment value (0.8Hz) based on the second reference frequency; the current of the middle roller stirrer is increased by the thirty-eighth preset adjustment value (80A) based on the third reference current, and the frequency is increased by the thirty-ninth preset adjustment value (0.8Hz) based on the third reference frequency; the current of the far roller stirrer is increased by the fortieth preset adjustment value (60A) based on the fourth reference current, and the frequency is decreased by the forty-first preset adjustment value (0.5Hz) based on the fourth reference frequency. In order to improve the penetration ability of the far roller stirrer, the frequency of the far roller stirrer can usually be reduced to ensure that it penetrates the thicker billet shell and acts on the liquid core. The box-type electromagnetic stirrer has a significant increase in volume, forming a strong stirring in the zero segment. The near roller stirrer 300 and the medium roller stirrer 310 have a significant increase in volume and frequency, forming a strong global closed-loop circulating flow field to flush the solute enrichment zone. The far roller stirrer 320 has a full-amplitude increase in volume to achieve fine-tuning of the final composition, which is suitable for severe segregation.

[0049] The second anomaly is specifically classified into mild, moderate, and severe levels, and each level is matched with specific current and frequency adjustment methods for box-type electromagnetic stirrers and near-roller, medium-roller, and far-roller stirrers. This achieves quantification of anomaly classification and concretization of adjustment strategies, solving the problems of lack of specific quantitative standards and clear basis for adjusting the control of uneven composition. By classifying anomaly levels with clear numerical thresholds, the determination of composition segregation has a precise quantitative standard. At the same time, an adjustment combination of near- and medium-stage core stirring and far-stage auxiliary stirring is designed for each level. Mild anomalies are gently adjusted to achieve initial solute diffusion, while moderate and severe anomalies gradually increase stirring intensity and frequency to form a full-domain stirring cycle, allowing the billet composition to reach the preset requirements efficiently and uniformly, and avoiding recurrence of composition segregation.

[0050] The main cause of the third anomaly is insufficient number of nucleation nuclei and uneven distribution of supercooling. The adjustment principle is that the medium roller stirrer 310 is the nucleation nucleus multiplication core area; the near roller stirrer 300 assists in breaking the dendrites that have melted in the zero segment, providing nucleation nuclei for the medium roller stirrer 310; and the far roller stirrer 320 ensures that the crystal nuclei grow uniformly until the end of solidification.

[0051] The third abnormality has multiple levels, which are divided as follows: When 60%≤η<65%, it is the third mild abnormality level of the third abnormality. The corresponding third mild adjustment strategy is as follows: the frequency of the box-type electromagnetic stirrer is reduced by the forty-third preset adjustment value (0.5Hz) based on the first reference frequency; the current of the near roller stirrer is increased by the forty-fourth preset adjustment value (80A) based on the second reference current, and the frequency is increased by the forty-fifth preset adjustment value (1.0Hz) based on the second reference frequency; the current of the middle roller stirrer is increased by the forty-sixth preset adjustment value (100A) based on the third reference current, and the frequency is increased by the forty-seventh preset adjustment value (1.2Hz) based on the third reference frequency; the current of the far roller stirrer is increased by the forty-eighth preset adjustment value (60A) based on the fourth reference current, and the frequency is reduced by the forty-ninth preset adjustment value (0.8Hz) based on the fourth reference frequency. The box-type electromagnetic stirrer reduces the frequency to retain the nucleation supercooling, the near roller stirrer 300 increment breaks dendrites to provide the initial nucleation core, the middle roller stirrer 310 maximum increment generates high-frequency micro-perturbation to trigger a large number of non-spontaneous nucleations, and the far roller stirrer 320 increment ensures the initial growth of crystal nuclei and adapts to slight nucleation deficiency.

[0052] When 55% ≤ η < 60%, it is the third moderate anomaly level (advanced step) of the third anomaly. The corresponding third moderate adjustment strategy is as follows: the current of the box-type electromagnetic stirrer is increased by the fiftieth preset adjustment value (10A) based on the first reference current, and the frequency is decreased by the fifty-first preset adjustment value (0.3Hz) based on the first reference frequency; the current of the near roller stirrer is increased by the fifty-second preset adjustment value (100A) based on the second reference current, and the frequency is increased by the fifty-third preset adjustment value (1.2Hz) based on the second reference frequency; the current of the middle roller stirrer is increased by the fifty-fourth preset adjustment value (120A) based on the third reference current, and the frequency is increased by the fifty-fifth preset adjustment value (1.6Hz) based on the third reference frequency; the current of the far roller stirrer is increased by the fifty-sixth preset adjustment value (80A) based on the fourth reference current, and the frequency is decreased by the fifty-seventh preset adjustment value (1.2Hz) based on the fourth reference frequency.

[0053] When η < 55%, it is the third severe abnormality level (enhanced ladder) of the third abnormality. The corresponding third severe adjustment strategy is as follows: the current of the box-type electromagnetic stirrer is increased by the fifty-eighth preset adjustment value (20A) based on the first reference current, and the frequency is decreased by the fifty-ninth preset adjustment value (0.2Hz) based on the first reference frequency; the current of the near roller stirrer is increased by the sixtieth preset adjustment value (120A) based on the second reference current, and the frequency is increased by the sixty-first preset adjustment value (1.5Hz) based on the second reference frequency; the current of the middle roller stirrer is increased by the sixty-second preset adjustment value (150A) based on the third reference current, and the frequency is increased by the sixty-third preset adjustment value (2.0Hz) based on the third reference frequency; the current of the far roller stirrer is increased by the sixty-fourth preset adjustment value (100A) based on the fourth reference current, and the frequency is decreased by the sixty-fifth preset adjustment value (1.5Hz) based on the fourth reference frequency. The box-type electromagnetic stirrer maintains flow field stability with small increments and retains supercooling by reducing frequency. The near-roller stirrer with a larger increment of 300 violently breaks dendrites and forms nanoscale nucleation cores. The medium-roller stirrer with a larger increment of 310 generates strong high-frequency micro-disturbances, triggering large-scale non-spontaneous nucleation. The far-roller stirrer with a larger increment of 320 ensures uniform growth of crystal nuclei until the end of solidification, which is suitable for severe nucleation insufficiency.

[0054] The third type of anomaly is classified, and specific current and frequency adjustment methods are matched for each level of the box-type electromagnetic stirrer and the near-roller, medium-roller, and far-roller stirrers, realizing the quantification of anomaly classification and the visualization of adjustment strategies. By clearly defining the equiaxed crystal ratio threshold to classify the anomaly level, the determination of insufficient nucleation has an intuitive and quantitative standard; mild anomalies focus on nucleation core proliferation, while severe anomalies enhance the supply and growth of nucleation cores. Non-spontaneous nucleation is triggered by high-frequency micro-perturbations, allowing the equiaxed crystal ratio of the billet to be rapidly and stably increased to above the preset requirements.

[0055] In some embodiments of the present invention, the main cause of the fourth anomaly is the coupling between columnar crystal growth and component segregation. In the near-roller stirrer region 300, columnar crystal growth intensifies solute enrichment, which in turn accelerates columnar crystal growth. Therefore, it is necessary to simultaneously suppress columnar crystal growth and homogenize the components. The fourth anomaly can be considered a combination of the first and second anomalies. Two adjustment strategies can be set using the first and second anomalies respectively, and the larger parameter adjustment value in the two strategies is taken as the final determined adjustment value.

[0056] Of course, in some other embodiments, adjustment strategies can also be set separately. The adjustment principle is as follows: the near roller stirrer 300 takes into account both columnar crystal suppression and initial solute diffusion; the middle roller stirrer 310 mainly adjusts the homogenization of components and assists in suppressing columnar crystals; and the far roller stirrer 320 realizes the end-stage assistance of dual defect treatment.

[0057] Specifically, the fourth anomaly is classified into multiple levels based on the degree of coupling between compositional deviation and the proportion of columnar crystals: When 5%≤ΔC+ΔG<62%, it is the fourth mild anomaly level (mild coupling) of the fourth anomaly. The corresponding fourth mild adjustment strategy of the fourth adjustment strategy is as follows: the current of the box-type electromagnetic stirrer is increased by the sixty-sixth preset adjustment value (80A) based on the first reference current, and the frequency is increased by the sixty-seventh preset adjustment value (0.2Hz) based on the first reference frequency; the current of the near roller stirrer is increased by the sixty-eighth preset adjustment value (50A) based on the second reference current, and the frequency is increased by the sixty-ninth preset adjustment value (0.5Hz) based on the second reference frequency; the current of the middle roller stirrer is increased by the seventieth preset adjustment value (40A) based on the third reference current, and the frequency is increased by the seventy-first preset adjustment value (0.5Hz) based on the third reference frequency; the current of the far roller stirrer is increased by the seventy-second preset adjustment value (20A) based on the fourth reference current. The box-type electromagnetic stirrer with a strong incremental increase simultaneously achieves zero-segment dendrite melting and solute mixing. The near-roller stirrer with a superimposed incremental increase takes into account both columnar crystal suppression in the coarse-grained region and initial solute diffusion. The medium-roller stirrer with a micro-increase assists in component homogenization. The far-roller stirrer with a micro-increase fine-tunes the final indicators.

[0058] When 62%≤ΔC+ΔG<69%, it is the fourth moderate anomaly level (moderate coupling) of the fourth anomaly. The corresponding fourth moderate adjustment strategy is as follows: the current of the box-type electromagnetic stirrer is increased by the seventy-third preset adjustment value (100A) based on the first reference current, and the frequency is increased by the seventy-fourth preset adjustment value (0.5Hz) based on the first reference frequency; the current of the near roller stirrer is increased by the seventy-fifth preset adjustment value (70A) based on the second reference current, and the frequency is increased by the seventy-sixth preset adjustment value (0.5Hz) based on the second reference frequency; the current of the middle roller stirrer is increased by the seventy-seventh preset adjustment value (60A) based on the third reference current, and the frequency is increased by the seventy-eighth preset adjustment value (0.5Hz) based on the third reference frequency; the current of the far roller stirrer is increased by the seventy-ninth preset adjustment value (40A) based on the fourth reference current, and the frequency is decreased by the eightieth preset adjustment value (0.5Hz) based on the fourth reference frequency. The box-type electromagnetic stirrer has a large increment to suppress zero-segment columnar crystals and achieve solute mixing; the near-roller stirrer 300 has a large increment to take into account the treatment of dual defects; the medium-roller stirrer 310 has an increment to enhance the homogenization of components; and the far-roller stirrer 320 assists in the dispersion of crystal nuclei and fine-tuning of components.

[0059] When 69% ≤ ΔC + ΔG, it is the fourth severe anomaly level (severe coupling) of the fourth anomaly. The corresponding fourth severe adjustment strategy is as follows: the current of the box-type electromagnetic stirrer is increased by the eighty-first preset adjustment value (100A) based on the first reference current, and the frequency is increased by the eighty-second preset adjustment value (0.5Hz) based on the first reference frequency; the current of the near roller stirrer is increased by the eighty-third preset adjustment value (90A) based on the second reference current, and the frequency is increased by the eighty-fourth preset adjustment value (0.8Hz) based on the second reference frequency; the current of the middle roller stirrer is increased by the eighty-fifth preset adjustment value (80A) based on the third reference current, and the frequency is increased by the eighty-sixth preset adjustment value (0.8Hz) based on the third reference frequency; the current of the far roller stirrer is increased by the eighty-seventh preset adjustment value (60A) based on the fourth reference current, and the frequency is decreased by the eighty-eighth preset adjustment value (0.5Hz) based on the fourth reference frequency. The box-type electromagnetic stirrer significantly increases the volume to suppress columnar crystals in the zero segment. The near-roller stirrer (300mm) significantly increases the volume to form a strong stirring zone that suppresses columnar crystals and promotes solute diffusion. The medium-roller stirrer (310mm) significantly increases the volume to achieve full-domain homogenization of severe segregation. The far-roller stirrer (320mm) significantly increases the volume to ensure that the dual-defect treatment effect continues until the end of solidification. The fourth anomaly is specifically classified into mild, moderate, and severe according to the degree of coupling. For each level, specific adjustment methods for the current and frequency of the box-type electromagnetic stirrer, near-roller stirrer, medium-roller stirrer, and far-roller stirrer are matched. This realizes the quantification of the classification of complex anomalies and the visualization of the adjustment strategy, solving the problems of no targeted control scheme for complex defects and the inability to simultaneously treat dual defects. An adjustment combination is designed for each level, which takes into account dual defects in the near segment, adjusts the main composition in the middle segment, and assists in optimization in the far segment. Mild coupling and gentle control simultaneously alleviate dual defects, while moderate and severe coupling enhance the stirring intensity, achieving simultaneous improvement in columnar crystal suppression and composition homogenization, allowing the various indicators of the cast billet to efficiently meet the preset requirements.

[0060] In some embodiments of the present invention, before returning to step S2, all preset adjustment values ​​are increased by their respective preset growth values. For example, if the initial value of the first preset adjustment value is 50A, and further parameter adjustment is needed when the equiaxed crystal ratio requirement is not met, the first preset adjustment value needs to be increased by 20A (the preset growth value corresponding to the first preset adjustment value) before returning to step S2. By increasing all preset adjustment values ​​before returning to step S2, the adaptive strengthening of the control strategy is achieved, solving the problem of repeated parameter adjustment after a single ineffective adjustment in the prior art. When a single adjustment strategy fails to meet the preset quality requirements, the preset adjustment values ​​corresponding to the box-type electromagnetic stirrer 200, the near-roller stirrer 300, the middle roller stirrer 310, and the far-roller stirrer 320 are automatically increased, giving the subsequent adjustment strategy a stronger control intensity. This allows for targeted solutions to unresolved quality anomalies, avoiding prolonged production cycles and increased production costs caused by repeated inefficient parameter adjustments. Simultaneously, the adaptive parameter adjustment amplitude strengthening design gives the method of the present invention the ability to self-optimize and iteratively provide feedback. Of course, in some other embodiments, other adjustable process parameters can be adjusted before returning to step S2. For example, if the equiaxed crystal ratio of the billet is low and the columnar crystals are well-developed, the casting speed can be appropriately reduced to prolong the action time of the molten steel in the electromagnetic stirring zone, which is conducive to the breakage and nucleation of columnar crystals. If the composition of the billet is severely segregated, the casting speed can be slightly reduced to prolong the stirring and mass transfer time in the liquid phase cavity and improve the uniformity of solute distribution. If the equiaxed crystal ratio is insufficient, the superheat can be appropriately reduced to reduce the liquid phase temperature gradient and promote grain nucleation and equiaxed crystal growth. If the superheat is too high, it is easy to cause rapid growth of columnar crystals. The superheat can be controlled within the target range by controlling the temperature of the molten steel and using reasonable sedation and heat preservation methods. If there is central looseness, segregation, and excessively long columnar crystals, the secondary cooling intensity can be appropriately weakened to make the solidification front more gentle, which is conducive to the development of equiaxed crystals. If there are surface cracks and excessive reheating, the secondary cooling intensity can be appropriately enhanced to improve the uniformity of billet shell growth and achieve quality synergy optimization with electromagnetic stirring.

[0061] It is understandable that all the above preset adjustment values ​​can be adjusted and changed as needed to adapt to different working conditions.

[0062] This invention also provides a system for improving the quality of cast billets through electromagnetic stirring, comprising: a detection module for detecting the equiaxed crystal ratio and composition distribution of the produced cast billets; a judgment and analysis module for judging whether the equiaxed crystal ratio meets a first preset requirement and whether the composition distribution meets a second preset requirement; if the equiaxed crystal ratio and composition distribution meet the first and second preset requirements respectively, then production is maintained with the current parameters; if the equiaxed crystal ratio does not meet the first preset requirement and / or the composition distribution does not meet the second preset requirement, then an anomaly classification is obtained through analysis; and an adjustment module for adjusting the billets according to the anomaly classification and implementing corresponding adjustment strategies. The strategy includes adjusting at least one of the following: adjusting the current of the box-type electromagnetic stirrer, adjusting the frequency of the box-type electromagnetic stirrer, adjusting the current of the roller-type electromagnetic stirrer, and adjusting the frequency of the roller-type electromagnetic stirrer. The box-type electromagnetic stirrer 200 is installed at the bottom of the crystallizer 100. The roller-type electromagnetic stirrer is used to guide the cast billet output from the crystallizer 100. A detection feedback module is used to detect the cast billet produced after the adjustment strategy is applied, obtain the equiaxed crystal ratio and composition distribution of the cast billet, and determine whether the equiaxed crystal ratio and composition distribution meet the preset requirements. If yes, the current parameters are maintained and production continues; if not, the analysis module and the adjustment module repeat their work. This significantly improves the intelligence and automation level of the production process.

[0063] The present invention also provides a storage medium storing a computer program that, when executed by a processor, implements a method for improving the quality of a cast billet through electromagnetic stirring.

[0064] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for improving the quality of cast billets by electromagnetic stirring, characterized in that, Includes the following steps: S1, to detect the equiaxed crystal ratio and composition distribution of the produced billet; S2, determine whether the equiaxed crystal ratio meets the first preset requirement and whether the composition distribution meets the second preset requirement. If the equiaxed crystal ratio and composition distribution meet the first and second preset requirements respectively, then maintain the current parameters and continue production. If the equiaxed crystallinity does not meet the first preset requirement or / and the composition distribution does not meet the second preset requirement, the analysis will obtain an anomaly classification. S3, according to the abnormal classification, the corresponding adjustment strategy is implemented. The adjustment strategy includes at least one of adjusting the current of the box electromagnetic stirrer, adjusting the frequency of the box electromagnetic stirrer, adjusting the current of the roller electromagnetic stirrer, and adjusting the frequency of the roller electromagnetic stirrer. The box electromagnetic stirrer (200) is installed at the bottom of the crystallizer (100). The roller electromagnetic stirrer is used to guide the billet output by the crystallizer (100). S4. Inspect the billet produced after adjusting the strategy to obtain the equiaxed crystal ratio and composition distribution of the billet, and determine whether the equiaxed crystal ratio and composition distribution meet the preset requirements: if yes, maintain the current parameters and continue production; if no, return to step S2.

2. The method for improving the quality of cast billets by electromagnetic stirring according to claim 1, characterized in that, The analysis yields anomaly classifications, specifically including: Obtain the proportion of columnar crystals and determine whether the proportion of columnar crystals in the cast billet meets the third preset requirement; If the composition distribution meets the second preset requirement and the proportion of columnar crystals in the billet does not meet the third preset requirement, the anomaly is classified as the first anomaly. If the composition distribution does not meet the second preset requirement and the proportion of columnar crystals in the billet meets the third preset requirement, the abnormality is classified as the second abnormality. If the composition distribution meets the second preset requirement and the proportion of columnar crystals in the billet meets the third preset requirement, then the abnormality is classified as the third abnormality. If the composition distribution does not meet the second preset requirement and the proportion of columnar crystals in the billet does not meet the third preset requirement, then the abnormality is determined to be the fourth abnormality.

3. The method for improving the quality of cast billets by electromagnetic stirring according to claim 2, characterized in that, The adjustment strategies include a first adjustment strategy, a second adjustment strategy, a third adjustment strategy, and a fourth adjustment strategy, respectively corresponding to the first abnormality, the second abnormality, the third abnormality, and the fourth abnormality; The first adjustment strategy includes increasing the current of the box-type electromagnetic stirrer and increasing the current of the roller-type electromagnetic stirrer; The second adjustment strategy includes increasing the current of the box-type electromagnetic stirrer, increasing the frequency of the box-type electromagnetic stirrer, and increasing the current of the roller-type electromagnetic stirrer; The third adjustment strategy includes increasing or maintaining the current of the box-type electromagnetic stirrer, decreasing the frequency of the box-type electromagnetic stirrer, and increasing the current of the roller-type electromagnetic stirrer. The fourth adjustment strategy includes increasing the current of the box-type electromagnetic stirrer, increasing the frequency of the box-type electromagnetic stirrer, and increasing the current of the roller-type electromagnetic stirrer.

4. The method for improving the quality of cast billets by electromagnetic stirring according to claim 3, characterized in that, The roller electromagnetic stirrer is provided in three groups: a near roller stirrer (300), a middle roller stirrer (310), and a far roller stirrer (320). The near roller stirrer (300), the middle roller stirrer (310), and the far roller stirrer (320) are distributed sequentially in the direction away from the crystallizer (100) and spaced apart along the billet extension direction.

5. The method for improving the quality of cast billets by electromagnetic stirring according to claim 4, characterized in that, The first, second, third, and fourth anomalies each have multiple levels, and the first, second, third, and fourth adjustment strategies correspond to the first, second, third, and fourth anomalies, respectively, and have multiple levels of adjustment strategies.

6. The method for improving the quality of cast billets by electromagnetic stirring according to claim 4, characterized in that, The reference for adjusting the values ​​of each parameter in the first, second, third, and fourth adjustment strategies is the reference value of each parameter, which is determined based on the current process parameters.

7. The method for improving the quality of cast billets by electromagnetic stirring according to claim 6, characterized in that, The third preset requirement is that the proportion of columnar crystals ΔG is less than 50%; the multiple levels of the first anomaly are divided according to the following: When 50%≤ΔG≤55%, it is the first mild abnormality level of the first abnormality. The corresponding first mild adjustment strategy of the first adjustment strategy is: the current of the box electromagnetic stirrer is increased by a first preset adjustment value based on the first reference current, and the current of the near roller stirrer (300) is increased by a second preset adjustment value based on the second reference current. The current of the medium roller agitator (310) is increased by a third preset adjustment value based on the third reference current; When 55 < ΔG ≤ 60%, it is the first moderate abnormality level of the first abnormality. The corresponding first moderate adjustment strategy is: the current of the box electromagnetic stirrer is increased by a fourth preset adjustment value based on the first reference current, and the frequency is increased by a fifth preset adjustment value based on the first reference frequency. The current of the near-roller agitator (300) is increased by a sixth preset adjustment value based on the second reference current, and the frequency is increased by a seventh preset adjustment value based on the second reference frequency. The current of the medium roller agitator (310) is increased by the eighth preset adjustment value based on the third reference current, and the frequency is increased by the ninth preset adjustment value based on the third reference frequency. The current of the remote roller agitator (320) is increased by the tenth preset adjustment value based on the fourth reference current; When ΔG>60%, it is the first severe abnormality level of the first abnormality. The corresponding first severe adjustment strategy is: the current of the box electromagnetic stirrer is increased by the eleventh preset adjustment value based on the first reference current, and the frequency is increased by the twelfth preset adjustment value based on the first reference frequency. The current of the near-roller agitator (300) is increased by a thirteenth preset adjustment value based on the second reference current, and the frequency is increased by a fourteenth preset adjustment value based on the second reference frequency. The current of the medium roller agitator (310) is increased by the fifteenth preset adjustment value based on the third reference current, and the frequency is increased by the sixteenth preset adjustment value based on the third reference frequency; The current of the remote roller mixer (320) is increased by the seventeenth preset adjustment value based on the fourth reference current, and the frequency is decreased by the eighteenth preset adjustment value based on the fourth reference frequency.

8. The method for improving the quality of cast billets by electromagnetic stirring according to claim 1, characterized in that, Before the return step S2, it also includes increasing all preset adjustment values ​​by their respective preset growth values.

9. A system for improving the quality of cast billets by electromagnetic stirring, characterized in that, include: The detection module is used to detect the equiaxed crystal ratio and composition distribution of the produced billets; The judgment and analysis module is used to determine whether the equiaxed crystal ratio meets the first preset requirement and whether the composition distribution meets the second preset requirement. If the equiaxed crystal ratio and composition distribution meet the first and second preset requirements respectively, then the current parameters are maintained and production continues. If the equiaxed crystallinity does not meet the first preset requirement or / and the composition distribution does not meet the second preset requirement, the analysis will obtain an anomaly classification. An adjustment module is used to perform corresponding adjustment strategies according to the anomaly classification. The adjustment strategies include at least one of adjusting the current of the box-type electromagnetic stirrer, adjusting the frequency of the box-type electromagnetic stirrer, adjusting the current of the roller-type electromagnetic stirrer, and adjusting the frequency of the roller-type electromagnetic stirrer. The box-type electromagnetic stirrer (200) is installed at the bottom of the crystallizer (100). The roller-type electromagnetic stirrer is used to guide the billet output from the crystallizer (100). The detection feedback module is used to detect the billet produced after the adjustment strategy is implemented, obtain the equiaxed crystal ratio and composition distribution of the billet, and determine whether the equiaxed crystal ratio and composition distribution meet the preset requirements.

10. A storage medium storing a computer program, characterized in that, When the computer program is executed by the processor, it implements the method for improving the quality of the billet by electromagnetic stirring as described in any one of claims 1 to 8.

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