A method and system for suppressing longitudinal oscillation of ultra-wide stainless steel slab continuous casting billets

Abstract

The application discloses a method and system for inhibiting longitudinal movement of an ultra-wide stainless steel slab continuous casting billet, and belongs to the field of high-end manufacturing. In view of the problem of longitudinal movement before cutting caused by the accumulation of elastic deformation energy of the billet in the straightening section and the horizontal section and the periodic release under the action of the crystallizer vibration, the application scheme comprises the following steps: reducing the accumulation of elastic deformation energy by reverse differential cooling regulation, that is, enhancing the cooling of the arc section and weakening the cooling of the straightening section; and configuring the power of the driving unit in the straightening and horizontal sections to the minimum power threshold required to inhibit the movement, so as to enhance the system damping. The two aspects are coordinated, and the disturbance is resisted from the source, so that the longitudinal movement of the billet is effectively inhibited, the flame cutting slit is ensured to be flat, and the quality of the ultra-wide stainless steel slab continuous casting is significantly improved.

Description

Technical Field

[0001] This invention belongs to the field of high-end manufacturing technology, specifically relating to continuous metal casting technology, and particularly to a method and system for suppressing longitudinal inching of ultra-wide stainless steel slabs in continuous casting. Background Technology

[0002] In the continuous casting production process of slabs, such as Figure 1 As shown, molten steel is poured into the tundish and flows into the inner cavity of the crystallizer. The periphery where the molten steel contacts the inner cavity begins to solidify, forming a billet shell. It then enters the area of ​​the support guide rollers equipped with cooling nozzles, further forming a fully solidified high-temperature billet. The billet continuously enters the cutting area of ​​a flame cutter, where it is cut into billets of a preset length before being conveyed to subsequent processing steps. (Reference) Figure 2a and Figure 2b To ensure that the kerf cut by the flame cutter is perpendicular and straight to the length of the billet, the guide wheel of the flame cutter disengages from the guide rail and sits on the billet by gravity, moving synchronously with the billet. The cutting torch moves relative to the flame cutter in a direction perpendicular to the length of the billet.

[0003] For ultra-wide stainless steel slabs, especially those 3 meters or wider, a frequent, intermittent longitudinal abnormal movement, known in the art as "longitudinal inching," occurs during continuous production before flame cutting. This phenomenon causes the flame cutter, which relies on gravity to contact the slab, to be unable to keep up with the slab's speed fluctuations in real time due to its own significant inertia. This results in unexpected relative displacement between the cutting torch and the slab, ultimately causing serrated or arc-shaped defects in the cut, such as... Figure 3 As shown in the image. This defect severely affects the quality of the cast billet, leading to rejection in subsequent rolling processes and requiring additional manual repairs, which significantly increases production costs.

[0004] Currently, conventional approaches to solving such problems tend to focus on two directions. First, at the electrical control level, speed compensation is applied to the drive roller motors to maintain dynamic load balance. This method emphasizes the balanced distribution of output among multiple motors, but it only addresses the consistency of the electrical drive system itself and does not intervene in the mechanical state and energy accumulation process of the billet itself. Therefore, it cannot fundamentally suppress the longitudinal inching caused by the accumulation and release of elastic deformation energy within the billet. Second, at the secondary cooling process level, the temperature field and stress-strain state of the billet are controlled by differentiating the cooling water volume between the inner and outer arc sides in different continuous casting sections. The technical purpose of this approach is to prevent bending deformation of the billet during continuous casting. The direction and dimension of its cooling differentiation are designed to control the overall morphology of the billet. The cooling intensity adjustment logic used is inner and outer arc differentiation, which is fundamentally different from the technical approach of "reverse differentiation along the casting direction" in this invention. It does not address the reverse configuration of the cooling strategy for the energy accumulation and periodic release mechanism unique to longitudinal inching.

[0005] After in-depth research, the inventors discovered that the fundamental mechanism that causes longitudinal inching of ultra-wide stainless steel slabs is: (1) After increasing the drawing speed, the solidified slab shell located in the arc section is relatively thin and has poor resistance to deformation. The slab shell undergoes significant tensile deformation as it slides down the guide roller.

[0006] (2) After entering the straightening section and the horizontal section, the thickness of the billet shell increases and the temperature decreases significantly. At this time, the billet that stays between the rollers of each sector in the straightening section and the horizontal section undergoes significant elastic deformation due to its low temperature and high elastic modulus, accumulating huge elastic deformation energy.

[0007] (3) This accumulated elastic deformation energy is not stable. Under the influence of other dynamic factors of the casting machine, especially under the periodic downward thrust generated by the crystallizer vibration on the billet, it will be suddenly and violently released once it reaches its limit. This periodic release of energy is the direct driving force that causes the billet to have sometimes fast and sometimes slow longitudinal inching in the straightening and horizontal sections.

[0008] In existing technologies, neither motor load balancing control nor other techniques used to solve problems are based on the aforementioned mechanism of "elastic deformation energy accumulation and release" to systematically address the longitudinal inching problem of the cast billet. In particular, no existing technology combines specific modes of secondary cooling intensity regulation with specific configurations of drive power to synergistically suppress energy accumulation from both the source and the disturbance of energy release. Summary of the Invention

[0009] The present invention aims to solve the above-mentioned problems existing in the prior art and provides a method and system for suppressing longitudinal inching of ultra-wide stainless steel slabs in continuous casting, thereby ensuring the flatness of the flame cutting kerf and significantly improving the quality of the slab.

[0010] To achieve the above objectives, the present invention adopts the following technical solution: This invention provides a method for suppressing longitudinal inching in ultra-wide stainless steel slabs during continuous casting, applicable to continuous casting machines comprising an arc-shaped section, a straightening section, and a horizontal section arranged sequentially along the casting direction. The core of this method lies in addressing the inching mechanism simultaneously from two levels—"source reduction" and "dampening of disturbance"—based on a fundamental understanding of the aforementioned inching mechanism, thereby creating a synergistic effect. Specifically, it includes: First, the secondary cooling intensity of the arc-shaped section and the straightening section is adjusted in a reverse differential manner through the cooling control module. Specifically, the cooling intensity of the arc-shaped section is enhanced to be higher than the conventional first reference strength; at the same time, the cooling intensity of the straightening section is weakened to be lower than the conventional second reference strength. The purpose of this reverse configuration is: applying stronger cooling to the arc-shaped section causes the billet shell to thicken earlier, which gives the billet higher structural stiffness before entering the straightening zone, thereby significantly reducing the total amount of elastic deformation energy that can be accumulated subsequently from the source; applying weaker cooling to the straightening section can slow down the rate of temperature decrease of the billet and reduce its temperature gradient in the straightening zone, thereby reducing its elastic modulus and effectively delaying and reducing the accumulation rate and peak value of elastic deformation energy in the straightening and horizontal zones.

[0011] Second, the power configuration module configures the drive power for the drive units located in the straightening section and / or the horizontal section. The configured drive power no longer merely meets the conventional billet pulling resistance, but rather meets a minimum power threshold specifically designed to suppress longitudinal inching of the billet, determined based on the continuous casting machine's structural and process parameters. Increasing the drive power is significant because when elastic deformation energy is inevitably partially released, generating an instantaneous dynamic thrust on the billet, a drive unit with sufficient power reserves can provide a powerful electromagnetic torque to counteract this dynamic disturbance in real time, acting as a "damper" to stabilize the billet pulling speed.

[0012] Most importantly, the aforementioned "reverse differential control" and "power configuration" are not simply parallel operations, but rather have a deep synergistic effect. The former aims to weaken the intensity of the "disturbance source," while the latter enhances the system's "resistance" to residual disturbances. The ultimate effect of their synergistic effect is to fundamentally suppress the longitudinal inching of the cast billet.

[0013] In a preferred embodiment, the reverse differential regulation is achieved by introducing an enhancement coefficient. and reduction coefficient Quantification is performed. That is, the cooling water volume in the arc-shaped section is adjusted. ( Cooling water volume of straightening section (2) ( ).

[0014] Furthermore, after extensive process experiments, it has been verified that for ultra-wide stainless steel slabs, The preferred value range is , The preferred value range is Even more ingenious is that the aforementioned and The specific value is not fixed, but is set to be adapted to the high-temperature elastic modulus of the steel being cast. The larger the high-temperature elastic modulus of the steel, the stronger its ability to accumulate elastic deformation energy under the same deformation. Therefore, a larger reverse cooling gradient is needed to suppress it, i.e., the adaptation is to take a larger value. Values ​​and smaller ones The specific adaptation relationship is as follows: the higher the high-temperature elastic modulus of the steel, the greater the required reverse gradient of cooling intensity, i.e., a larger value should be selected. Values ​​and smaller ones value.

[0015] In another preferred embodiment, based on regression analysis of a large amount of process data and the construction of a composite load model of "bulging force-straightening force-elastic dynamic release force", this invention proposes and discloses for the first time a quantitative calculation formula for determining the minimum power threshold: In the formula: The motor power of the drive unit (4) is expressed in kW. This represents the maximum width of the cast billet, in meters (m). This represents the maximum thickness of the cast billet, in meters (m). The basic radius of the arc of the continuous casting machine is given in meters. The radius of curvature of the outer arc at the position of the drive roller in the drive unit (4) is in meters; This is the maximum production speed, expressed in m / min. This represents the combined transmission efficiency of the reducer and motor. The coefficients 488, exponents 1.26, -1.26, and 0.056 in this formula are empirical parameters specifically determined to evaluate the damping power required for ultra-wide stainless steel slabs to generate and release elastic deformation energy under specific process conditions. They are derived from data regression of the composite load model and can accurately guide motor selection, avoiding power redundancy or insufficiency.

[0016] The present invention also provides a continuous casting system for implementing the above-described method. The core of this system lies in the integration of a cooling control module and a power configuration module, in addition to the conventional arc-shaped section, straightening section, horizontal section, and drive unit arranged along the casting flow direction. The cooling control module is used to execute the aforementioned reverse-differentiated cooling intensity control strategy; the power configuration module is coupled to the drive unit to ensure that the configured drive power meets the aforementioned minimum power threshold for suppressing longitudinal inching of the billet.

[0017] Further optimization: To avoid thermal stress on the billet surface caused by abrupt changes in cooling intensity between the arc-shaped and straightening sections, this invention proposes setting a transition cooling zone between the two to achieve a smooth transition in cooling intensity. Furthermore, the roll gap shrinkage of multiple fan-shaped segments in the straightening and horizontal sections can be optimized to create a gradient distribution from large to small, thereby further mitigating the mechanical clamping force applied to the billet and eliminating mechanical factors that may induce inching.

[0018] Compared with the prior art, the technical solution of the present invention can achieve the following significant beneficial effects: A fundamental solution to the inching problem: Based on a breakthrough understanding of its mechanism, this solution addresses both the source of energy accumulation and the damping of disturbance release simultaneously, achieving a fundamental and effective suppression of inching, rather than a temporary relief of the phenomenon.

[0019] Unexpected synergistic effects were produced: comparative experiments of the examples show that the combined use of "reverse cooling regulation" and "power threshold configuration" produced a superior suppression effect that far exceeds the simple summation of the two.

[0020] Precise power configuration is achieved: The first proposed empirical power formula provides a quantitative design basis for suppressing inching of specific mechanisms, making motor selection scientific and precise, and taking into account both reliability and economy.

[0021] It has broad material adaptability: the correlation rule between the cooling coefficient and the high-temperature elastic modulus of steel makes this method flexible and accurate to various steel grades such as 304 stainless steel, 316L stainless steel, and high carbon steel, and has strong universality.

[0022] The overall quality of the billet has been significantly improved: Through optimizations such as smooth cooling transition and gradient roll gap setting, while solving the problem of inching, the overall temperature and stress distribution of the billet has been further improved, which is conducive to improving the overall quality of the billet. Attached Figure Description

[0023] Figure 1 This is a simplified diagram of the slab continuous casting production process.

[0024] Figure 2a This is a schematic diagram of the cutting process of a flame cutting machine.

[0025] Figure 2b This is a diagram illustrating an engineering application of a flame cutting machine.

[0026] Figure 3 This is a schematic diagram of the sawtooth-shaped defect at the right end of the cast billet.

[0027] Figure 4 This is a schematic diagram of the curvature radius of the straightening point and the radius of the main machine during the straightening stage of the billet.

[0028] Figure 5 This is a schematic diagram illustrating the kerf cutting effect of a cast billet produced using the method described in this embodiment of the invention.

[0029] Explanation of reference numerals in the attached figures: 1. Liquid core; 2. Solidification shell; 3. Straightening starting roller; 4. Straightening roller; 5. Straightening ending roller; R, main machine radius; Rs, outer arc curvature radius at the straightening roller; 6. Ladle; 7. Intermediate tank; 8. Crystallizer; 9. Cooling nozzle; 10. Support rail; 11. Flame cutter; 12. First cutting gun; 13. Second cutting gun; 14. Track. Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the embodiments described herein are for illustrative purposes only and are not intended to limit the scope of protection of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without inventive effort are within the scope of protection of this invention.

[0031] In the description of this invention, "stretching direction" refers to the main direction of movement of the billet in the continuous casting machine, that is, the direction from the crystallizer to the flame cutter; "longitudinal inching" refers to the unstable motion state of the billet along the stretching direction, with its speed sometimes fast and sometimes slow; "reverse differential control" refers to the control method that enhances and weakens the cooling intensity of the arc section and the straightening section along the stretching direction, respectively, so that they exhibit opposite changing trends.

[0032] To facilitate understanding of the application scenarios and technical problems solved by this invention, let's first combine... Figure 1 , Figure 2a and Figure 4 A brief description of the main equipment components and process parameters involved in the traditional continuous casting process and cutting device is provided.

[0033] refer to Figure 1In the traditional slab continuous casting production process, ladle 6 receives and holds molten steel, which is then buffered by intermediate ladle 7 before being injected into the inner cavity of crystallizer 8. The molten steel begins to solidify at the periphery in contact with the inner cavity of crystallizer 8, forming a slab shell. The slab with its liquid core then enters the area of ​​support guide rollers 10 equipped with cooling nozzles 9. In this area, the cooling nozzles 9 spray secondary cooling water to continuously cool the slab, while the support guide rollers 10 provide support and guidance. The fully solidified, high-temperature slab then continuously enters the cutting area of ​​flame cutter 11, where it is cut to a predetermined length.

[0034] refer to Figure 2a The flame cutter 11 is equipped with a first cutting gun 12, a second cutting gun 13, and a track 14. During cutting, the first cutting gun 12 and the second cutting gun 13 reciprocate along the track 14 in a direction perpendicular to the length of the billet, so as to complete the transverse cutting of the billet.

[0035] refer to Figure 4 During the billet straightening stage, a liquid core 1 still exists inside the billet, surrounded by a solidified shell 2. The billet is straightened sequentially by the straightening starting roller 3, several straightening rollers 4, and the straightening ending roller 5. In the figure, R is the main machine radius, and R_s is the outer arc curvature radius at the straightening roller. These parameters form the geometric basis for determining the configuration of the drive unit in the straightening section.

[0036] Example 1 This embodiment is used to specifically illustrate the core method of the present invention, and through comparative experiments, strongly demonstrates the synergistic effect between "reverse differential cooling" and "specific power configuration".

[0037] The basic arc radius of the continuous casting machine selected in this embodiment The length is 9.8m, mainly producing ultra-wide stainless steel slabs. Specific slab specifications are as follows: width... m, thickness m. The steel grade used is 304 stainless steel, and the maximum production drawing speed is... The speed is 1.3 m / min. In the straightening section, the radius of curvature of the outer arc at the drive roller where the force is greatest is... The combined transmission efficiency of the reducer and motor is 1384m. The value is 0.9.

[0038] S1: Establish a "reverse differentiation" cooling strategy Based on the high-temperature elastic modulus characteristics of 304 stainless steel, which falls within the medium-low elastic modulus range, the adjustment coefficient for cooling intensity is determined as follows: The strengthening coefficient is taken as... That is, the amount of cooling water applied to the arc-shaped section 1. Its benchmark cooling water volume 1.1 times; take the reduction coefficient. That is, the amount of cooling water applied to the straightening section 2. Its benchmark cooling water volume 0.95 times.

[0039] This scheme achieves a reverse differentiated cooling intensity configuration along the billet pulling direction: "arc-shaped reinforcement - straightening reduction." The principle is as follows: applying enhanced cooling to the arc section promotes earlier billet shell growth and thickening, making it more rigid, thereby reducing the upper limit of elastic deformation energy that can accumulate after the billet enters the straightening zone; applying reduced cooling to the straightening section slows down the rate of temperature drop of the billet, maintaining a lower elastic modulus in the straightening and horizontal sections, thus reducing the ability to accumulate elastic deformation energy under given deformation conditions. The combined effect of these two methods significantly reduces the driving energy of inching at its source.

[0040] S2: Calculate and configure the drive power to meet the "inching suppression threshold". Substitute all the above parameters into the power condition formula for calculation: The calculated result is approximately 28.56 kW.

[0041] This means that in order for drive unit 4 to have sufficient dynamic damping capability to suppress the inching caused by the release of elastic deformation energy, its motor power must reach at least 28.56kW. Therefore, the motor power configured for drive unit 4 here is 30kW. This power value is significantly higher than the power required under conventional design when only considering steady-state billet pulling resistance (e.g., 20-22kW). The core function of its added power margin is to act as an "active damper" to offset the instantaneous dynamic thrust on the billet when elastic deformation energy is released in real time.

[0042] S3: Collaborative Operation and Effect Comparison Verification To accurately verify and quantify the "synergistic effect," three operating condition groups were set up for comparative experiments in the engineering practice of the same continuous casting machine. Each group ran for 100 heats, and the average number of longitudinal inching events of the billet per hour and the resulting defective rate of the cut quality were recorded and statistically analyzed. During the experiment, other process parameters, equipment status, and environmental conditions of the continuous casting machine remained consistent.

[0043] Comparative Example A (using cooling control only): The implementation scheme is to execute only the "reverse differentiation" cooling strategy determined in S1 of this embodiment. , However, the motor power of drive unit 4 remains at the conventional design power of 22kW without being increased. Results show that the average frequency of longitudinal inching of the cast billet is 8.0 times / hour, resulting in a cut defect rate of 15.0%.

[0044] Analysis: This solution reduces the accumulation of elastic deformation energy at its source, thus alleviating inching to some extent compared to when no measures are taken. However, when the residual elastic deformation energy inevitably accumulates to a certain level and is suddenly released, a conventional power motor cannot provide a sufficiently strong dynamic damping torque to counteract the disturbance, and therefore cannot completely suppress inching.

[0045] Comparative Example B (Power Configuration Only): The implementation scheme uses a conventional, uniform cooling method (i.e., , (A reference cooling water volume is applied to both the arc section and the straightening section), but the motor power of the drive unit 4 is increased to 30kW according to the calculation result of S2 in this embodiment. The results show that the average frequency of longitudinal inching of the billet is 6.0 times / hour, and the defect rate of the cut is 10.0%.

[0046] Analysis: This solution enhances the system's dynamic damping capability, providing more effective resistance to inching disturbances. However, because it doesn't control the problem at its source, the billet's stiffness is low when it enters the straightening section, resulting in a still significant accumulation of elastic deformation energy in the straightening and leveling sections. When this enormous energy is released, the impact intensity frequently exceeds the damping limit provided by the 30kW motor. Therefore, while the inching phenomenon is improved, it remains quite severe.

[0047] Example 1 (Collaborative Solution of this Application): The implementation scheme is to simultaneously execute S1 (reverse differential cooling) of this example. , S1 and S2 (drive power configured at 30kW) work together to achieve the desired effect. Results show that the average frequency of longitudinal inching in the cast billet is reduced to below 1.0 times / hour, and the cut quality is extremely smooth, as shown in the image. Figure 5 As shown, the non-compliance rate dropped to below 1.0%.

[0048] Synergistic effect analysis: The above experimental results demonstrate that the combined approach in Example 1—with an inching frequency below 1 time per hour—is far superior to the individual effects of Comparative Example A (8 times per hour) and Comparative Example B (6 times per hour). More importantly, this effect is not a simple linear summation of the two approaches. A simple summation would have resulted in an expected frequency of 4 to 6 times per hour. The actual result is that the combined approach improved the inching frequency by an order of magnitude—reducing it from the tens digit to below the single digit—achieving an unexpected technical effect that no other individual technique could possibly achieve.

[0049] The underlying mechanism of this significant synergistic effect lies in the fact that reverse cooling regulation physically "reduces" the energy source of the inching phenomenon—namely, the total amount of elastic deformation energy that the billet can accumulate in the straightening and horizontal sections—so that the drive unit only needs to resist the residual disturbances that have been "reduced." Simultaneously, the enhanced drive power provides a powerful dynamic damping torque, which can easily and efficiently suppress the impact of these residual, periodic energy releases on the billet speed. The combination of these two factors perfectly achieves the systemic optimization goal of "1+1 is far greater than 2," which is also the core manifestation of the significant inventiveness of this invention.

[0050] Example 2 This embodiment is used to illustrate the enhancement coefficient. and reduction coefficient The method of adapting values ​​to different steel grades demonstrates the flexible applicability of the method of the present invention to different steel grades.

[0051] For steel grades with different high-temperature elastic moduli, the principle of "the larger the elastic modulus, the more intense the reverse cooling gradient" should be followed when adapting parameters to provide inching suppression capability that matches the inherent properties of the material.

[0052] When the steel grade is 316L stainless steel, its high-temperature modulus of elasticity is at a medium level. Suitable parameter: reinforcement coefficient. Attenuation coefficient The power configuration is based on the actual production casting speed corresponding to that steel grade. The process parameters are then substituted back into the power condition formula to calculate the minimum power threshold and select the appropriate motor.

[0053] When the steel grade is high-carbon steel slab, its high-temperature elastic modulus is relatively high. Suitable parameter: reinforcement coefficient. Attenuation coefficient The power configuration method is the same as above.

[0054] By adapting parameters related to the high-temperature elastic modulus of the steel grade, it is ensured that the "source reduction" capability of cooling intensity control is precisely matched with the inherent properties of the material for steel grades with different inching sensitivities, thus achieving the goal of effectively suppressing inching. This demonstrates the wide applicability and precise adjustability of the method of this invention.

[0055] Example 3 This embodiment illustrates optimized techniques for the distribution of the transition cooling zone and the shrinkage roll gap gradient. These optimized techniques, when combined with the core synergistic solution of Embodiment 1, result in superior surface and internal quality of the cast billet.

[0056] Implementation of smooth cooling transition: In the continuous casting system, an independent transition cooling zone 8 is set between the end of the arc section 1 and the beginning of the straightening section 2. The cooling control module 5 finely adjusts the cooling nozzles in this zone, ensuring that the cooling water volume is 1.1 times the reference volume. The water volume will be smoothly transitioned to 0.95 times the baseline volume using a linear decreasing method. The cooling curve, which might have exhibited a step-like abrupt change at the junction of the arc-shaped section 1 and the straightening section 2, transforms into a smoothly descending oblique line within the transition cooling zone 8. This smooth transition completely avoids the sudden change in the surface temperature gradient of the billet that could be caused by a step change in cooling intensity, thereby effectively preventing the generation of surface thermal stress cracks and ensuring the surface quality of the billet while suppressing inching.

[0057] Implementation of the gradient distribution of shrinkage roll gap: For the multiple fan-shaped segments 9 arranged sequentially within the straightening section 2 and the horizontal section 3, the roll gap shrinkage between adjacent fan-shaped segments is optimized. Conventional configurations may result in equal or irregular shrinkage between adjacent fan-shaped segments, while the optimized scheme of this invention configures them to have a gradient decreasing distribution along the billet pulling direction. For example, the shrinkage between the first and second fan-shaped segments near the straightening starting point is set to a maximum of 3mm, and then decreases to 2mm, 1mm, and 0.5mm respectively. This gradient shrinkage configuration makes the radial constraint force applied to the outer surface of the billet change more gently along the pulling direction, avoiding the induction or aggravation of elastic deformation and subsequent inching of the billet due to sudden changes in mechanical clamping force. This, together with the aforementioned temperature control and power configuration methods, forms a triple comprehensive guarantee.

[0058] Example 4 This embodiment illustrates the continuous casting system provided by the present invention. According to the continuous casting machine structure described in the above embodiments, the continuous casting system for suppressing longitudinal inching of ultra-wide stainless steel slabs includes, in sequence along the casting flow direction: a crystallizer, an arc section 1, a straightening section 2, a horizontal section 3, and a flame cutter 6.

[0059] The key difference between this system and existing continuous casting systems is that it also integrates a cooling control module 5 and a power configuration module.

[0060] Cooling control module 5 internally stores reinforcement coefficients corresponding to different steel grades. and reduction coefficient Configuration parameters and baseline cooling water volume , The data enables the execution of the reverse differential cooling strategy as described in Examples 1 and 2. The cooling control module 5 is connected to the control valves of the cooling nozzle groups respectively located in the arc section 1, the straightening section 2, and the optional transition cooling zone 8 via control lines, so as to realize independent and precise control of the cooling water volume in each section.

[0061] The power configuration module is typically integrated into the main programmable logic controller (PLC) of the continuous casting machine. The module's memory stores the power condition formula and its coefficients: 488, 1.26, -1.26, and 0.056. During actual operation, the operator inputs the continuous casting machine's structural parameters under the current production conditions. , , , and process parameters , The power configuration module automatically calculates the minimum power threshold required to suppress inching and issues a power configuration command to the inverter of drive unit 4 or directly to the motor controller to ensure the straightening section motor. and horizontal section motor The output driving torque meets the threshold requirement.

[0062] In addition, the continuous casting system also includes a transition cooling zone 8 to realize the above-mentioned optimization scheme and a fan-shaped section group 9 with a gradient roll gap shrinkage configuration in terms of physical structure configuration, in order to further optimize the quality of the cast billet on the basis of synergistic suppression of inching.

[0063] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Those skilled in the art can make various modifications or equivalent substitutions without departing from the essence and spirit of the present invention. 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 suppressing longitudinal inching of ultra-wide stainless steel slabs in continuous casting, applied to a continuous casting machine comprising an arc-shaped section (1), a straightening section (2), and a horizontal section (3) arranged sequentially along the casting direction, characterized in that, The method includes: The cooling intensity of the arc section (1) and the straightening section (2) is adjusted in a reverse differential manner by the cooling control module (5), so that the cooling intensity of the arc section (1) is higher than its first reference intensity, and the cooling intensity of the straightening section (2) is lower than its second reference intensity. The power configuration module configures the driving power for the drive unit (4) set in the straightening section (2) and / or the horizontal section (3), and the driving power meets the minimum power threshold required to suppress longitudinal inching caused by the accumulation and release of elastic deformation energy of the billet, which is determined based on the structural parameters and process parameters of the continuous casting machine. The reverse differential regulation works in conjunction with the power configuration to jointly suppress the longitudinal inching of the billet by reducing the accumulation of elastic deformation energy in the straightening section (2) and the horizontal section (3) and enhancing the damping ability of the system to release disturbances of elastic deformation energy.

2. The method according to claim 1, characterized in that, The method of controlling the secondary cooling intensity of the arc-shaped section (1) and the straightening section (2) in a reverse differential manner is specifically as follows: After adjustment, the cooling water volume of the arc-shaped section (1) satisfy: ; After adjustment, the cooling water volume of the straightening section (2) satisfy: ; in, The reference cooling water volume corresponding to the first reference strength. The reference cooling water volume corresponding to the second reference strength; For enhancement coefficients with values ​​greater than 1, This is the attenuation coefficient, which takes a value less than 1.

3. The method according to claim 2, characterized in that, The enhancement coefficient The range of values ​​is The attenuation coefficient The range of values ​​is .

4. The method according to claim 3, characterized in that, The enhancement coefficient and the reduction coefficient The specific value is configured in relation to the high-temperature elastic modulus of the steel being cast; Specifically, when the high-temperature elastic modulus of the steel increases, the adaptation is to select a larger value within the range specified in the value list. Value, and select the smaller one. The value, the high-temperature elastic modulus and , The fit relationship for the values ​​is: the higher the high-temperature elastic modulus, the greater the required reverse cooling gradient, i.e. The larger the value, The smaller the value.

5. The method according to claim 1, characterized in that, The minimum power threshold of the drive unit (4) is determined by the following power conditions: ； In the formula: The motor power of the drive unit (4) is expressed in kW. This represents the maximum width of the cast billet, in meters (m). This represents the maximum thickness of the cast billet, in meters (m). The basic radius of the arc of the continuous casting machine is given in meters. The radius of curvature of the outer arc at the position of the drive roller in the drive unit (4) is in meters; This is the maximum production speed, expressed in m / min. To improve the overall transmission efficiency of the reducer and motor; The coefficients 488, exponents 1.26, -1.26, and 0.056 are empirical parameters derived from a composite load model of "bulging force - straightening force - elastic dynamic release force" for the continuous casting process of ultra-wide stainless steel slabs, and obtained through regression analysis of a large amount of process data. They are specifically used to evaluate the damping power required to suppress longitudinal inching caused by the release of elastic deformation energy.

6. The method according to claim 5, characterized in that, The basic arc radius of the continuous casting machine The width of the cast billet is 9.8m. Not less than 3.0m, thickness The maximum production speed is between 0.20m and 0.25m. The speed is 1.3 m / min, and the radius of curvature of the outer arc of the drive roller is... The length is 1384m, and the transmission efficiency is... In the application scenario of taking 0.9, it is calculated that the drive unit (4) is equipped with a motor power of not less than 30kW.

7. The method according to claim 1, characterized in that, Also includes: A transition cooling zone (8) is provided between the end of the arc section (1) and the beginning of the straightening section (2). The cooling intensity in the transition cooling zone (8) is adjusted to smoothly transition from the enhanced cooling intensity of the arc section (1) to the weakened cooling intensity of the straightening section (2).

8. The method according to any one of claims 1 to 7, characterized in that, Also includes: The shrinkage roll gap of the multiple fan-shaped segments (9) set in the straightening section (2) and the horizontal section (3) is optimized so that the roll gap shrinkage between adjacent fan-shaped segments (9) is distributed in a gradient from large to small along the drawing direction.

9. A continuous casting system for suppressing longitudinal inching of ultra-wide stainless steel slabs in continuous casting, used to implement the method as described in any one of claims 1 to 8, the continuous casting system comprising an arc-shaped section (1), a straightening section (2), a horizontal section (3) arranged sequentially along the casting flow direction, and a drive unit (4) disposed in the straightening section (2) and / or the horizontal section (3), characterized in that, Also includes: The cooling control module (5) is configured to perform reverse differential cooling intensity control on the arc section (1) and the straightening section (2), such that the cooling intensity of the arc section (1) is higher than its first reference intensity and the cooling intensity of the straightening section (2) is lower than its second reference intensity. The power configuration module is coupled to the drive unit (4) and is configured to configure the drive unit (4) with a drive power that meets the minimum power threshold required to suppress longitudinal inching of the billet based on the structural and process parameters of the continuous casting system. The cooling control module (5) works in conjunction with the power configuration module.

10. The continuous casting system according to claim 9, characterized in that, It also includes a transition cooling zone (8) located between the end of the arc section (1) and the beginning of the straightening section (2), and the cooling control module (5) is further configured to regulate the cooling intensity of the transition cooling zone (8) so that it smoothly transitions from the enhanced cooling intensity of the arc section (1) to the weakened cooling intensity of the straightening section (2).

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