A method, system, and storage medium for controlling a cast slab solidification structure

Abstract

The application discloses a kind of methods for controlling casting blank solidification structure, system and storage medium.The present application determines the electrode down distance by detecting the reference liquid level height of the medium in the crystallizer, combined with the preset insertion depth, can ensure that the electrode insertion depth accurately matches the process requirements, avoid the insertion too shallow or too deep leading to unstable control effect.Combined with the actual temperature of the medium in the crystallizer, electrode down distance and environmental characteristics determine the electrode preheating temperature, fully consider the heat loss of electrode from the initial position to the medium in the process, heat the electrode to the preheating temperature before moving, effectively make up the heat loss in the process of electrode movement, avoid the problem of too large temperature difference between electrode and molten steel caused by directly inserting low-temperature electrode into high-temperature molten steel or considering heat loss after heating in the prior art.

Description

Technical Field

[0001] This invention relates to the field of steel processing technology, and in particular to a method, system, and storage medium for controlling the solidification structure of cast billets. Background Technology

[0002] The solidification structure of a cast billet is the core microstructure that determines the subsequent processing performance and final product quality of the steel. Its grain size, morphological uniformity, and growth orientation directly affect key indicators such as the steel's strength, toughness, and formability. It also plays a decisive role in the process adaptability of subsequent rolling and annealing processes. A refined and uniform solidification structure can effectively improve the overall mechanical properties of the cast billet and reduce defects such as cracks and segregation during subsequent processing. Conversely, a coarse and uneven solidification structure will lead to the deterioration of steel properties and significantly reduce the product qualification rate.

[0003] Currently, the main methods for controlling the solidification structure of cast billets in industrial production include microalloying control, continuous casting process parameter optimization, and physical field control. Among these, pulsed current control has become an important technical means for controlling the solidification structure of cast billets due to its advantages such as being non-contact, pollution-free, not changing the composition of molten steel during the control process, and effectively intervening in the grain nucleation and growth process. Its principle is to use the electromagnetic force and electromigration force generated by the pulsed current to act on the molten steel, breaking the growth trend of coarse grains within the molten steel, promoting fine grain nucleation, and thus achieving a refined and homogenized solidification structure. However, existing pulse current control technology, when applied to the solidification structure control of cast billets, generally suffers from low control precision and poor stability. The dynamic changes in the liquid level within the crystallizer are not considered during control, and the electrode insertion depth is set entirely based on experience, making it impossible to precisely adjust the insertion distance according to the actual liquid level. This results in inaccurate electrode insertion depths—too shallow or too deep—leading to unstable control effects. Furthermore, the electrodes are not preheated before insertion into the high-temperature molten steel. Direct insertion of a low-temperature electrode into the high-temperature molten steel not only makes it susceptible to damage due to thermal stress but also disrupts the stability of the local temperature field in the molten steel, interfering with the normal solidification process and affecting the conduction efficiency and current distribution uniformity of the pulse current loop. Additionally, the heat loss during the heating process before insertion into the medium (molten steel) is not considered, causing the electrode temperature to drop during movement and resulting in a significant temperature difference between the electrode and the medium upon insertion. Summary of the Invention

[0004] 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 controlling the solidification structure of cast billets.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A method for controlling the solidification structure of a cast billet includes the following steps: S1, detecting the liquid level of the medium in the crystallizer and using the detected liquid level as a reference liquid level, obtaining the actual height difference between the reference liquid level and the lower end of the electrode at the initial position; S2, obtaining the downward insertion distance of the electrode based on a preset insertion depth and the actual height difference; S3, detecting the actual temperature of the medium in the crystallizer and obtaining the preheating temperature of the electrode based on the downward insertion distance of the electrode and environmental characteristics, wherein the preheating temperature is higher than the actual temperature of the medium; S4, the heating device heats the electrode at the initial position to the preheating temperature and then stops heating; S5, the driving mechanism drives the electrode to move and descend the downward insertion distance relative to the initial position, so that the electrode extends into the medium in the crystallizer; S6, the pulse current power supply device is turned on to energize the electrode and the roller conveyor of the straightening machine, forming a closed current loop, thereby applying a pulse current to the molten steel.

[0006] Further, step S6 is followed by step S7, which specifically includes: S71, real-time detection and determination of whether molten steel is continuously added to the crystallizer: if yes, then proceed to step S72; if no, then proceed to step S74; S72, determination of whether the current liquid level of the medium in the crystallizer is lower than a first preset threshold: if yes, then turn off the pulse current power supply device; if no, then proceed to step S73; S73, determination of whether the difference between the current liquid level of the medium in the crystallizer and the reference liquid level is greater than a second preset threshold: if yes, then drive the electrode to rise and fall according to the liquid level difference, and update the reference liquid level to the current liquid level after the electrode rise and fall is completed; if no, then keep the electrode height unchanged; S74, determination of whether the difference between the current liquid level of the medium in the crystallizer and the reference liquid level is greater than a second preset threshold: if yes, then turn off the pulse current power supply device, and drive the electrode to move to the initial position.

[0007] Furthermore, the method of driving the electrode to rise and fall based on the liquid level difference specifically includes: when the current liquid level of the medium in the crystallizer is lower than the reference liquid level, the electrode is driven to fall and the falling distance is the liquid level difference; when the current liquid level of the medium in the crystallizer is higher than the reference liquid level, the electrode is driven to rise and the rising distance is the liquid level difference.

[0008] Furthermore, the heating device is an electromagnetic induction heating device.

[0009] Further, step S5 specifically includes: S51, the driving mechanism drives the electrode to rise to disengage from the electromagnetic induction heating device; S52, the driving mechanism drives the electrode to move horizontally above the crystallizer; S53, the driving mechanism drives the electrode to descend to a lower position relative to the initial position.

[0010] Further, step S53 specifically includes: S531, the driving mechanism drives the electrode to move at a first preset speed to a preset distance from the height of the reference liquid surface; S532, the driving mechanism drives the electrode to move at a second preset speed to descend a distance relative to the initial position, wherein the first preset speed is less than the second preset speed.

[0011] Furthermore, the environmental characteristics include the air temperature, humidity, and hot air velocity above the liquid surface in the crystallizer.

[0012] Furthermore, the electrodes are provided in multiple forms and are all mounted on an electrode support, and the driving mechanism is connected to the electrode support to drive all electrodes to move synchronously.

[0013] The present invention also provides a system for controlling the solidification structure of a cast billet, comprising: an actual height difference acquisition module for detecting the liquid level of the medium in the crystallizer and using the detected liquid level as a reference liquid level to obtain the actual height difference between the reference liquid level and the lower end of the electrode at the initial position; a downward insertion distance acquisition module for obtaining the downward insertion distance of the electrode based on a preset insertion depth and the actual height difference; a preheating temperature acquisition module for detecting the actual temperature of the medium in the crystallizer and obtaining the preheating temperature of the electrode based on the downward insertion distance of the electrode and environmental characteristics, wherein the preheating temperature is higher than the actual temperature of the medium; a heating device for heating the electrode at the initial position to the preheating temperature and then stopping heating; a driving mechanism for driving the electrode to move and descend the downward insertion distance relative to the initial position, so that the electrode extends into the medium in the crystallizer; and a pulse current power supply device for energizing the electrode and the straightening machine roller to form a closed current loop, thereby applying a pulse current to the molten steel.

[0014] The present invention also provides a storage medium storing a computer program that, when executed by a processor, implements the method for controlling the solidification structure of the cast billet.

[0015] The present invention has the following beneficial effects: Step S1 detects the reference liquid level height of the medium inside the crystallizer, calculates the actual height difference between it and the lower end of the electrode at the initial position, and combines this with the preset insertion depth in step S2 to determine the electrode insertion distance. This solves the problem of existing technologies where the electrode insertion depth is set based on experience and does not consider dynamic changes in the liquid level. It ensures that the electrode insertion depth accurately matches the process requirements, avoiding unstable control effects caused by insertion that is too shallow or too deep. Step S3 determines the electrode preheating temperature based on the actual temperature of the medium inside the crystallizer, the electrode insertion distance, and environmental characteristics. This fully considers the heat loss during the electrode's movement from the initial position into the medium. Step S4 heats the electrode to this preheating temperature before moving it, effectively compensating for heat loss during electrode movement. This avoids the problem of excessive temperature difference between the electrode and molten steel caused by directly inserting a low-temperature electrode into high-temperature molten steel or by not considering heat loss after heating, which is common in existing technologies. This reduces damage to the electrode caused by instantaneous thermal stress, extends electrode life, and reduces production equipment wear and maintenance costs. It also avoids the damage to the local temperature field of the molten steel caused by excessive temperature differences, ensuring the normal progress of the molten steel solidification process. Step S6 energizes the electrodes and the straightening machine rollers using a pulsed current power supply device, forming a stable closed current loop. This eliminates the need for additional loop components, simplifying the process structure. Simultaneously, the existing structure of the straightening machine rollers is utilized to achieve loop conduction, enabling the electromagnetic and electromigration forces generated by the pulsed current to act efficiently on the molten steel. This precisely controls the grain nucleation and growth process, helping to obtain a refined and uniform solidification structure in the cast billet.

[0016] 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

[0017] 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 one embodiment of the method of the present invention; Figure 2 This is a flowchart illustrating step S7 of the method of the present invention; Figure 3 This is a schematic diagram of the electrode support structure. 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 A preferred embodiment of the present invention provides a method for controlling the solidification structure of a cast billet, comprising steps S1, S2, S3, S4, S5 and S6.

[0023] S1, detect the liquid level of the medium in the crystallizer, and use the detected liquid level as the reference liquid level to obtain the actual height difference between the reference liquid level and the lower end of the electrode at the initial position.

[0024] S2, based on the difference between the preset insertion depth and the actual height, obtain the electrode's downward probe distance.

[0025] S3 detects the actual temperature of the medium inside the crystallizer and obtains the preheating temperature of the electrode based on the electrode's downward probe distance and environmental characteristics.

[0026] S4, the heating device heats the electrode at the initial position to the preheating temperature and then stops heating.

[0027] S5, the driving mechanism drives the electrode to move and descend a distance relative to the initial position, so that the electrode extends into the medium inside the crystallizer.

[0028] S6 activates the pulse current power supply device to energize the electrodes and the leveling machine rollers, forming a closed current loop and applying a pulse current to the molten steel. The negative output of the pulse current power supply device is connected to the leveling machine rollers via a cable, and the leveling machine rollers are in contact with the solidified steel billet. The positive output cable of the pulse current power supply device is connected to the metal electrodes, which are inserted into the molten steel. The electrodes are then connected to the negative electrode through the molten steel and the steel billet, thus forming a current loop through the molten steel. Using a rectifier, the positive pulse current is filtered out, retaining only the negative pulse current. The voltage is adjusted to -30~0V, the current to 0~2000A, and the frequency to 1~100HZ.

[0029] This invention provides a method for controlling the solidification structure of cast billets. Step S1 detects the reference liquid level height of the medium within the crystallizer, calculates the actual height difference between this level and the lower end of the electrode at the initial position, and combines this with Step S2 to determine the electrode insertion distance based on a preset insertion depth. This solves the problem in existing technologies where the electrode insertion depth is set empirically without considering dynamic changes in the liquid level, ensuring that the electrode insertion depth accurately matches process requirements and avoiding unstable control due to excessively shallow or deep insertion. Step S3 determines the electrode preheating temperature based on the actual temperature of the medium within the crystallizer, the electrode insertion distance, and environmental characteristics, fully considering heat loss during the electrode's movement from its initial position into the medium. Step S4 heats the electrode to this preheating temperature before movement, effectively compensating for heat loss during electrode movement and avoiding the problem of excessive temperature difference between the electrode and molten steel caused by directly inserting a low-temperature electrode into high-temperature molten steel or by not considering heat loss after heating, as in existing technologies. This reduces damage to the electrode caused by instantaneous thermal stress, extends electrode lifespan, and reduces production equipment wear and maintenance costs. It also avoids damage to the local temperature field of the molten steel caused by excessive temperature differences, ensuring the normal progress of the molten steel solidification process. Step S6 energizes the electrodes and the leveling machine rollers using a pulsed current power supply, creating a stable closed-loop current circuit. This eliminates the need for additional circuit components, simplifying the process structure. Simultaneously, the existing structure of the leveling machine rollers is utilized to achieve circuit conduction, allowing the electromagnetic and electromigration forces generated by the pulsed current to efficiently act on the molten steel. This precisely controls the grain nucleation and growth process, contributing to a refined and uniform solidification structure in the cast billet. Through precise control of electrode insertion depth, matching of preheating temperature, and the construction of a stable closed-loop current circuit, this approach collaboratively solves problems such as low control accuracy, high equipment wear, and unstable solidification processes in existing pulsed current control technologies. It effectively improves the solidification structure quality of the cast billet, enhances the consistency of magnetic and mechanical properties, reduces subsequent processing difficulty and product defect rates, and eliminates the need for additional complex equipment or high costs. It is suitable for the large-scale production needs of high-end cast billets, demonstrating excellent industrial practicality and economic efficiency.

[0030] Reference Figure 2Step S6 is followed by step S7. Step S7 specifically includes steps S71, S72, S73, and S74.

[0031] S71: Real-time detection and determination of whether molten steel is continuously added to the crystallizer: if yes, proceed to step S72; if no, proceed to step S74. As the core starting point for the entire subsequent liquid level and electrode control logic, this step enables real-time identification of the crystallizer's molten steel replenishment status. Sensors (visual and temperature sensors) can be used to monitor the tundish or submerged entry nozzle to determine if there is continuous molten steel injection. Step S71 divides the process control into two completely different branches, ensuring that subsequent liquid level determination, electrode operation, and pulse current control are matched to actual production conditions. Distinguishing between continuous molten steel pouring (normal production state) and molten steel replenishment cessation avoids equipment malfunction and pulse current control failure caused by using a unified control logic. This provides a basis for subsequent precise and differentiated process control, ensuring the targeted and reasonable nature of the control behavior.

[0032] S72, detect the current liquid level of the medium in the crystallizer and determine whether the current liquid level of the medium in the crystallizer is lower than the first preset threshold: if yes, turn off the pulse current power supply device, and after turning it off, continue to detect the liquid level. If the liquid level is higher than the first preset threshold, proceed to step S73; if no, execute step S73, and after executing step S73, turn on the pulse current power supply device. A safety threshold is determined for the liquid level height during continuous molten steel pouring, and a corresponding pulse current control action is triggered. The first preset threshold is the lower limit of contact between the molten steel and the crystallizer. That is, even if the electrode descends to the preset minimum position, the required contact length with the molten steel is not met. When the liquid level is lower than this value, the insufficient amount of molten steel will cause unstable contact between the electrode and the molten steel, and frequent switching of "contact-disconnection" will easily occur, causing repeated on / off switching of the pulse current circuit. This will not only completely disable the solidification structure control, but also generate current surges that will damage the power supply equipment and electrodes. Timely shutdown of the pulse current power supply equipment not only protects the pulse current power supply equipment, electrodes and other hardware, but also avoids the energy waste caused by ineffective current application, and prevents solidification quality defects of the billet caused by excessively low liquid level.

[0033] S73, determine whether the difference between the current liquid level height and the reference liquid level height in the current crystallizer is greater than a second preset threshold: if yes, drive the electrode to rise or fall according to the liquid level difference, and update the reference liquid level height to the current liquid level height after the electrode rise or fall is completed; if no, keep the electrode height unchanged. Under the premise of continuous steel pouring and the liquid level being within a safe range, accurately determine the dynamic small fluctuations of the liquid level, and realize adaptive fine-tuning or maintenance of the electrode position. During continuous molten steel pouring, the liquid level fluctuates dynamically. If the electrode position is fixed, the actual insertion depth will deviate from the preset value, reducing the control effect. When the liquid level difference exceeds the preset threshold, the electrode rises and falls precisely with the liquid level difference, ensuring that the electrode insertion depth is always consistent with the process preset value. This allows the pulse current to act continuously and stably on the target control area, ensuring the uniformity and stability of the solidification structure control effect. When the difference does not exceed the threshold, the electrode height remains unchanged to avoid frequent electrode raising and lowering that could cause equipment wear, while also reducing the redundancy of process operations and improving control efficiency. The operation of updating the reference liquid level height ensures that subsequent liquid level difference judgments are always based on the latest actual liquid level, guaranteeing the accuracy of subsequent control.

[0034] S74 determines whether the difference between the current liquid level and the reference liquid level in the crystallizer is greater than a second preset threshold. If yes, the pulse current power supply is shut off, and the drive mechanism moves the electrode to its initial position. If no, the electrode height remains unchanged. For the condition where molten steel supply stops, the magnitude of the liquid level drop is determined, triggering a linkage operation of pulse current shutdown and electrode reset. After molten steel supply stops, the liquid level in the crystallizer will continue to drop, at which point there is no need to continue applying pulse current to regulate the solidification structure. When the liquid level difference exceeds the preset threshold, the pulse current is shut off promptly to avoid abnormal continuity of the current circuit due to the drop in liquid level, especially when the liquid is about to separate from the molten steel but not completely separated. At this time, the current is prone to arc discharge, current spikes, and violent fluctuations, accompanied by alternating instantaneous open and short circuits. Current spikes and surges will exceed the rated operating range of the equipment, impacting the internal rectifier, inverter modules, and relay protection components. This can cause equipment protection tripping, or even burn out power devices, damage circuit boards, and reduce the equipment's service life. The high temperatures generated by the electric arc discharge can concentrate and burn the electrode tips, causing electrode erosion and melting, leading to electrode deformation. The localized high temperatures of the arc can disrupt the temperature field of the molten steel within the crystallizer, resulting in localized overheating, remelting of the solidified layer, and quality defects such as surface cracks and inclusion aggregation in the cast billet. Frequent switching on and off and current surges can generate a large amount of induced electromotive force, forming overvoltages that can break down insulating components in the circuit, causing safety hazards such as leakage and short circuits. Driving the electrode to its initial position prevents damage caused by friction and collision with crystallizer components, and also returns the electrode to its initial standby state, preparing it for the next pour, ensuring equipment safety and the continuity of subsequent production.

[0035] Step S7 enables steel replenishment detection, liquid level judgment, and adaptive electrode control, achieving real-time and intelligent response to dynamic changes in the liquid level within the crystallizer. This solves the problem of fixed electrode positions in existing processes, which cannot adapt to changes in liquid level. When steel is continuously replenished, the system can determine whether to continue applying pulse current based on the liquid level height threshold, preventing electrode control failure when the liquid level is too low. Simultaneously, the system uses liquid level difference judgment to achieve adaptive electrode raising and lowering, ensuring that the electrode insertion depth always matches process requirements and allowing the pulse current to operate stably. When steel replenishment stops, the system can promptly cut off power and reset the electrodes to their initial positions based on changes in liquid level. This avoids the application of ineffective pulse current, reduces energy waste, prevents equipment damage, and improves the continuity, stability, and safety of the process and equipment operation.

[0036] It is understandable that, to further ensure that the initial insertion depth of the electrode meets the requirements, a step S56 can be added between steps S5 and S6. Step S56 specifically includes: detecting the current liquid level height, determining the height difference between the current liquid level height and the reference liquid level height, adjusting the height of the electrode according to this difference, and updating the reference liquid level height to the current liquid level height after adjustment. That is, if the current liquid level height is higher than the reference liquid level height, the electrode is adjusted to rise by a distance equal to the height difference; if the current liquid level height is lower than the reference liquid level height, the electrode is adjusted to fall by a distance equal to the height difference. Usually, the liquid level does not change much during the electrode movement, and in some other embodiments, step S56 may be omitted.

[0037] In a specific embodiment of the present invention, the electrode is driven to rise and fall according to the liquid level difference driving mechanism. Specifically, when the current liquid level of the medium in the crystallizer is lower than the reference liquid level, the electrode is driven to fall by a distance equal to the liquid level difference; when the current liquid level of the medium in the crystallizer is higher than the reference liquid level, the electrode is driven to rise by a distance equal to the liquid level difference. This clarifies the precise matching relationship between the electrode lifting distance and the liquid level difference, providing a quantifiable execution standard for the dynamic control of the electrode. It eliminates the need to recalculate the descent distance, simplifies the control logic of electrode lifting and falling, and improves the process's response speed to changes in liquid level. Simultaneously, the electrode lifting distance is completely consistent with the liquid level difference, ensuring from an operational perspective that the electrode insertion depth is consistent with the preset insertion depth at the initial insertion, completely compensating for the difference in insertion depth caused by liquid level differences, and further ensuring the stability of the coagulation structure control effect.

[0038] In a specific embodiment of the present invention, the heating device is an electromagnetic induction heating device. By limiting the heating device to an electromagnetic induction heating device, the advantages of rapid heating rate and high temperature control accuracy can be utilized. This allows the electrodes to be quickly heated to a preset preheating temperature, effectively shortening the electrode heating time and improving overall process efficiency. Furthermore, electromagnetic induction heating is a non-contact heating method, avoiding physical contact wear between the electrodes and the heating device. This extends the service life of the heating device and prevents surface roughness caused by contact friction from affecting the contact area with molten steel, thus ensuring the integrity of the electrode structure. Simultaneously, the electromagnetic induction heating process generates no contaminants, meeting the requirements for steel cleanliness in billet production and preventing the introduction of impurities during the heating process from affecting material properties.

[0039] In a specific embodiment of the present invention, step S5 specifically includes steps S51, S52 and S53.

[0040] S51, the drive mechanism drives the electrode to rise until it is detached from the electromagnetic induction heating device; S52, the drive mechanism drives the electrode to move horizontally above the crystallizer; S53, the drive mechanism drives the electrode to descend to its initial position, decreasing the distance it would otherwise travel. By first raising the electrode to detach from the heating device, then moving it horizontally above the crystallizer, and finally lowering it, the movement trajectory avoids any scraping or collision between the electrode and the electromagnetic induction heating device during movement, preventing equipment damage and electrode deformation, and ensuring the safety and stability of the electrode movement.

[0041] In a further embodiment of the present invention, step S53 specifically includes: S531, the driving mechanism drives the electrode to move at a first preset speed to a preset distance from the reference liquid surface; S532, the driving mechanism drives the electrode to move at a second preset speed to descend a distance relative to the initial position, wherein the first preset speed is less than the second preset speed. Dividing the electrode descent process into two levels of speed control—low speed when approaching the reference liquid surface and high speed when moving away from the liquid surface—achieves a balance between process stability and efficiency. Low-speed approach and insertion into the liquid surface effectively avoids molten steel splashing caused by the electrode rapidly impacting the molten steel surface, preventing damage to the molten steel surface, ensuring the stability of the temperature and flow fields of the molten steel within the crystallizer, and avoiding interference with the solidification process; high-speed movement significantly shortens the overall time of electrode descent, reduces additional heat loss during the descent process, and improves process execution efficiency.

[0042] Reference Figure 3In some embodiments of the present invention, multiple electrodes 100 are provided and all are mounted on electrode supports 200. The driving mechanism is connected to the electrode supports to drive all electrodes to move synchronously. This enables multi-position pulse current output, expands the range through which the pulse current passes, and improves internal uniformity. It is understood that the driving mechanism includes a translation driving mechanism and a lifting driving mechanism. A guide rail 500 can be provided above the crystallizer, and a translation frame 300 is slidably mounted on the guide rail 500. The translation frame 300 is driven to move by the translation driving mechanism. The electrode supports 200 are movably mounted on the translation frame 300 via guide rods 210, and the electrode supports 200 are driven to rise and fall by the lifting driving mechanism. The translation drive mechanism can be a motor and a lead screw and nut pair to move the translation frame, or it can be a drive mechanism with telescopic drive function such as an electric push rod or a hydraulic cylinder. The lifting drive mechanism can be a hydraulic rod, a winch, or a motor. If a motor is used, different transmission forms can be used to drive the electrode support to lift and lower. For example, a rack 220 can be set on the electrode support 200, and the output shaft of the lifting drive mechanism (motor) is connected to a gear 400 adapted to the rack. The rotation of this gear drives the electrode support 200 to lift and lower. A wire guide can be set on one side of the electrode support 200, and a wire hole 230 can be set on the wire guide for the cable 110 connected to the upper end of the electrode 100 to pass through.

[0043] In a further embodiment of the present invention, the environmental characteristics include the air temperature, humidity, and hot air velocity above the liquid surface of the crystallizer. Temperature, humidity, and wind speed sensors can be preset at the opening at the top of the crystallizer to obtain these three data points. Step S3 specifically includes: S31, inputting the detected actual temperature of the medium inside the crystallizer, the electrode's downward insertion distance, and the environmental characteristics into the prediction model; S32, obtaining the electrode's preheating temperature. By defining the environmental characteristics as the air temperature, humidity, and hot air velocity above the liquid surface of the crystallizer, and obtaining the electrode preheating temperature through the prediction model, a comprehensive and accurate quantification of the factors affecting heat loss during electrode movement is achieved. This solves the problem of deviations in preheating temperature determination caused by considering only a single parameter and ignoring environmental factors in existing processes. By incorporating key environmental parameters such as temperature, humidity, and hot air velocity, the calculation of electrode temperature drop is more closely aligned with actual working conditions. Simultaneously, the application of the prediction model upgrades the determination of the preheating temperature from empirical judgment to scientific calculation, minimizing the deviation of the preheating temperature, ensuring that heat loss after electrode movement is accurately compensated, and ensuring that the temperature difference between the electrode and the medium is within a controllable range when the electrode is inserted into the molten steel.

[0044] In a specific embodiment of the present invention, the prediction model is established according to the following steps: S301, set the model input features as the actual temperature of the medium, the electrode probing distance, the ambient air temperature, and the ambient relative humidity; set the model output label as the electrode preheating temperature, which is the sum of the actual temperature of the medium and the measured temperature drop during the electrode movement process; S302: Collect historical process operation data of the billet continuous casting production line. The historical data includes valid samples. Each sample set contains input features and actual temperature drop values ​​during electrode movement. The electrode preheating temperature corresponding to this set of data is obtained by adding the actual temperature drop value of the electrode movement to the actual temperature of the medium. All input features and output labels are normalized.

[0045] S302, use historical data to train the prediction model to obtain the prediction model after training.

[0046] The model is trained using historical process data from the continuous casting production line, ensuring that the model's predictions closely match actual production conditions and avoiding a disconnect between the theoretical model and actual production. Normalization of input features and output labels effectively improves the model's training accuracy and prediction stability. The preheating temperature is defined as the actual temperature of the medium plus the measured temperature drop during electrode movement. This ensures, in principle, that the preheating temperature accurately compensates for the heat loss during electrode movement, avoiding subjective errors in temperature drop calculations and ensuring that the determination of the preheating temperature is rigorously scientific and data-driven. The prediction model can be based on gradient boosting trees, random forests, backpropagation (BP) neural networks, etc.

[0047] This invention also provides a system for controlling the solidification structure of a cast billet, comprising: an actual height difference acquisition module for detecting the liquid level of the medium in the crystallizer and using the detected liquid level as a reference liquid level to obtain the actual height difference between the reference liquid level and the lower end of the electrode at the initial position; a downward insertion distance acquisition module for obtaining the downward insertion distance of the electrode based on a preset insertion depth and the actual height difference; a preheating temperature acquisition module for detecting the actual temperature of the medium in the crystallizer and obtaining the preheating temperature of the electrode based on the downward insertion distance of the electrode and environmental characteristics, wherein the preheating temperature is higher than the actual temperature of the medium; a heating device for heating the electrode at the initial position to the preheating temperature and then stopping heating; a driving mechanism for driving the electrode to move and descend the downward insertion distance relative to the initial position, so that the electrode extends into the medium in the crystallizer; and a pulse current power supply device for energizing the electrode and the leveling machine rollers to form a closed current loop, thereby applying a pulse current to the molten steel. This system achieves integrated control of electrode insertion depth calculation, preheating temperature acquisition, electrode driving, and pulse current application, significantly improving the automation level of solidification structure control.

[0048] The present invention also provides a storage medium storing a computer program, which, when executed by a processor, implements a method for controlling the solidification structure of a cast billet.

[0049] 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 controlling the solidification structure of a cast billet, characterized in that, Includes the following steps: S1, detect the liquid level of the medium in the crystallizer, and use the detected liquid level as the reference liquid level to obtain the actual height difference between the reference liquid level and the lower end of the electrode at the initial position; S2, based on the difference between the preset insertion depth and the actual height, the downward probe distance of the electrode is obtained; S3, detect the actual temperature of the medium inside the crystallizer, and obtain the preheating temperature of the electrode based on the electrode's downward probe distance and environmental characteristics. The preheating temperature is higher than the actual temperature of the medium. S4, the heating device heats the electrode at the initial position to the preheating temperature and then stops heating; S5, the driving mechanism drives the electrode to move and descend a distance relative to the initial position, so that the electrode extends into the medium inside the crystallizer; S6 activates the pulse current power supply equipment to energize the electrodes and the straightening machine rollers, forming a closed current loop, thereby applying a pulse current to the molten steel.

2. The method for controlling the solidification structure of a cast billet according to claim 1, characterized in that, Step S6 is followed by step S7. Step S7 specifically includes: S71, real-time detection and determination of whether molten steel is continuously added to the crystallizer: If so, proceed to step S72; If not, proceed to step S74; S72, determine whether the current liquid level of the medium in the crystallizer is lower than the first preset threshold: If so, then shut down the pulse current power supply device; If not, proceed to step S73; S73, determine whether the difference between the current liquid level height of the medium in the crystallizer and the reference liquid level height is greater than the second preset threshold: If so, the electrode will be driven to rise and fall according to the liquid level difference driving mechanism, and the reference liquid level height will be updated to the current liquid level height after the electrode rise and fall is completed; If not, then keep the electrode height unchanged; S74, determine whether the difference between the current liquid level height of the medium in the crystallizer and the reference liquid level height is greater than the second preset threshold: If so, the pulse current power supply device is turned off, and the drive mechanism drives the electrode to move to the initial position.

3. The method for controlling the solidification structure of a cast billet according to claim 2, characterized in that, The step of driving the electrode to rise and fall based on the liquid level difference specifically includes: When the current liquid level of the medium inside the crystallizer is lower than the reference liquid level, the drive electrode descends and the descent distance is the liquid level difference. When the current liquid level of the medium inside the crystallizer is higher than the reference liquid level, the drive electrode rises and the rising distance is the liquid level difference.

4. The method for controlling the solidification structure of a cast billet according to claim 1, characterized in that, The heating device is an electromagnetic induction heating device.

5. The method for controlling the solidification structure of a cast billet according to claim 4, characterized in that, Step S5 specifically includes: S51, the drive mechanism drives the electrode to rise and disengage from the electromagnetic induction heating device. S52, the drive mechanism drives the electrode to translate above the crystallizer; S53, the drive mechanism drives the electrode to descend to a relative initial position and descend a certain distance.

6. The method for controlling the solidification structure of a cast billet according to claim 5, characterized in that, Step S53 specifically includes: S531, the drive mechanism drives the electrode to move at a first preset speed to a preset distance from the height of the reference liquid level; S532, the driving mechanism drives the electrode to move at a second preset speed to descend a distance relative to the initial position, wherein the first preset speed is less than the second preset speed.

7. The method for controlling the solidification structure of a cast billet according to claim 1, characterized in that, The environmental characteristics include the air temperature, humidity, and hot air velocity above the liquid surface in the crystallizer.

8. The method for controlling the solidification structure of a cast billet according to claim 1, characterized in that, The electrode is provided in multiple parts and is mounted on an electrode support. The driving mechanism is connected to the electrode support to drive all electrodes to move synchronously.

9. A system for controlling the solidification structure of a cast billet, characterized in that, include: The actual height difference acquisition module is used to detect the liquid level of the medium in the crystallizer and use the detected liquid level as the reference liquid level to obtain the actual height difference between the reference liquid level and the lower end of the electrode at the initial position. The insertion distance acquisition module is used to obtain the insertion distance of the electrode based on the preset insertion depth and the actual height difference; The preheating temperature acquisition module is used to detect the actual temperature of the medium inside the crystallizer and obtain the preheating temperature of the electrode based on the electrode's downward probe distance and environmental characteristics. The preheating temperature is higher than the actual temperature of the medium. A heating device is used to heat the electrodes at the initial position to the preheating temperature and then stop heating. A drive mechanism is used to drive the electrode to move and descend a distance relative to its initial position, so that the electrode extends into the medium inside the crystallizer. The pulse current power supply equipment is used to energize the electrodes and the roller conveyor of the straightening machine, forming a closed current loop, thereby applying a pulse current to the molten steel.

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

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