Rolling mill loop control method and device

Abstract

The invention discloses a rolling mill loop control method and device. The steel type and the thickness specification of to-be-rolled steel are obtained; according to the steel type and the thickness specification of the steel to be rolled, the proportionality coefficient and the integral time of a loop controller are dynamically adjusted; adjusting a loop angle position and a position ring setting reference value; the threading speed and head setting are optimized, and the loop rising height in the head tension building process is controlled. Thus, according to the scheme, through dynamic parameter adaptation, multi-system cooperative control and intelligent prediction maintenance, the adaptability bottleneck of traditional loop control on steel types and specifications is broken through, the precision, efficiency and stability of hot rolling production are remarkably improved, and meanwhile a foundation is laid for energy consumption optimization and intelligent upgrading.

Description

Technical Field

[0001] The present invention relates to the technical field of steel rolling, and particularly to a method and device for controlling a loop of a rolling mill. Background Art

[0002] In the process of hot rolling production, loop control and AGC (Automatic Gauge Control) system are key links to ensure product quality and production efficiency. Traditional loop control and automatic thickness control systems usually adopt fixed control parameters, which are difficult to adapt to the changes of different steel grades, thickness specifications and process conditions, resulting in problems such as tension fluctuations and uneven thickness in the production process, affecting product quality and production efficiency. Summary of the Invention

[0003] In view of the above problems, the present invention provides a method and device for controlling a loop of a rolling mill to improve the adaptability and control accuracy of the system.

[0004] According to a first aspect of the present invention, a method for controlling a loop of a rolling mill is provided, including the following steps:

[0005] Obtain the steel grade and thickness specification of the steel to be rolled;

[0006] Dynamically adjust the proportional coefficient and integral time of the loop controller according to the steel grade and thickness specification of the steel to be rolled;

[0007] Adjust the loop angle position and the set reference value of the position loop;

[0008] Optimize the head setting of the threading speed and control the loop height during the head tension establishment process.

[0009] Optionally, the dynamically adjusting the proportional coefficient and integral time of the loop controller according to the steel grade and thickness specification includes:

[0010] Obtain the historical rolling data of the historical rolled steel, where the historical rolling data includes the historical steel grade, historical thickness specification, and the proportional coefficient and integral time corresponding to the historical steel grade and the historical thickness specification;

[0011] Establish a mapping relationship table between the steel grade, thickness specification, proportional coefficient, and integral time according to the historical rolling data of the historical rolled steel;

[0012] Real-time obtain the steel grade and thickness specification of the steel to be rolled, and determine the proportional coefficient and integral time corresponding to the steel grade and specification thickness of the rolled steel according to the mapping relationship table, and send them to the loop controller.

[0013] Optionally, for high-hardness steel grades with a Rockwell hardness greater than 30, increase the proportionality coefficient and decrease the integration time; for thin-gauge strip steel with a thickness less than 4 mm, decrease the proportionality coefficient and increase the integration time.

[0014] Optionally, the adjustment of the loop angle position and the set reference value of the position loop includes:

[0015] Preset a static reference value for the loop angle position according to the rolling pass and the material elongation rate;

[0016] Obtain the strip speed difference in real time;

[0017] Perform dynamic compensation on the static reference value of the loop angle according to the strip speed difference;

[0018] Combine the hydraulic loop cylinder displacement feedback to correct the set reference value of the position loop.

[0019] Optionally, the combination of the hydraulic loop cylinder displacement feedback to correct the set reference value of the position loop includes:

[0020] Obtain the real-time displacement data of the hydraulic loop cylinder;

[0021] Calculate the deviation between the displacement data and the target displacement;

[0022] Adjust the proportionality coefficient and the integration time in the set reference value of the position loop according to the deviation and the change trend.

[0023] Optionally, the optimization of the threading speed head setting to control the loop height during the head building process includes:

[0024] Before the head of the steel to be rolled enters the loop, reduce the threading speed;

[0025] After the head of the steel to be rolled passes through each stand, gradually increase the speed according to a preset gradient;

[0026] Before the head of the steel to be rolled reaches the loop, lift the loop roll to a preset height;

[0027] Real-time monitor the loop roll height through a laser rangefinder or an encoder, and when the head of the steel to be rolled touches the loop, adjust it to the target loop height by using the PID algorithm.

[0028] Optionally, the preset height is 80% of the target loop height, and the error range of the target loop height is ±10 mm.

[0029] According to the second aspect of the present invention, there is provided a mill loop control device, including:

[0030] An acquisition module for acquiring the steel grade and thickness specification of the steel to be rolled;

[0031] A first adjustment module for dynamically adjusting the proportional coefficient and integral time of a loop controller according to the steel type and thickness specification of the steel to be rolled.

[0032] A second adjustment module for adjusting the loop angle position and the set reference value of the position loop.

[0033] A control module for optimizing the head setting of the threading speed and controlling the loop height during the head building tension process.

[0034] According to a third aspect of the present invention, there is provided a controller, which includes: a memory, a processor, and a computer program stored on the memory and executable on the processor, and the processor executes the foregoing mill loop control method.

[0035] According to a fourth aspect of the present invention, there is provided a mill device, characterized in that the mill device includes a mill and a controller installed on the mill, wherein the controller executes the foregoing mill loop control method.

[0036] One or more of the above technical solutions in the embodiments of this specification have at least the following technical effects:

[0037] A mill loop control method and device provided in the embodiments of this specification obtain the steel type and thickness specification of the steel to be rolled; dynamically adjust the proportional coefficient and integral time of the loop controller according to the steel type and thickness specification of the steel to be rolled; adjust the loop angle position and the set reference value of the position loop; optimize the head setting of the threading speed and control the loop height during the head building tension process. In this way, through dynamic parameter adaptation, multi-system collaborative control, and intelligent predictive maintenance, this solution breaks through the adaptability bottleneck of traditional loop control to steel types and specifications, significantly improves the accuracy, efficiency, and stability of hot rolling production, and at the same time lays a foundation for energy consumption optimization and intelligent upgrading.

[0038] The above description is only an overview of the technical solutions of the present invention. In order to be able to understand the technical means of the present invention more clearly, it can be implemented according to the content of the specification. And in order to make the above and other purposes, features, and advantages of the present invention more obvious and understandable, the following specifically describes the embodiments of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] By reading the following detailed description of the preferred embodiments, various other advantages and benefits will become clear to those of ordinary skill in the art. The drawings are only for the purpose of showing the preferred embodiments and are not considered to be a limitation of the present invention. And throughout the drawings, the same reference numerals are used to represent the same components. In the drawings:

[0040] Figure 1The flowchart of a loop control method for a rolling mill in an embodiment of the present invention is shown.

[0041] Figure 2 The schematic diagram of a loop of a rolling mill in an embodiment of the present invention is shown.

[0042] Figure 3 The block diagram of a loop control device for a rolling mill in an embodiment of the present invention is shown. Detailed implementation manners

[0043] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some but not all of the embodiments of the present invention. Generally, the components of the embodiments of the present invention described and illustrated in the accompanying drawings here can be arranged and designed in various different configurations.

[0044] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed present invention, but merely represents selected embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the scope of protection of the present invention.

[0045] It should be noted that: like reference numerals and letters denote like items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0046] In the description of the present invention, it should also be noted that, unless otherwise clearly defined and limited, the terms "arrange", "install", "connect", and "couple" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be a direct connection or an indirect connection through an intermediate medium, and it may be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0047] An embodiment of the present invention provides a loop control method for a rolling mill. Combining with Figure 1 the shown flowchart, the loop control method for the rolling mill includes steps 101 to 104:

[0048] Step 101: Obtain the steel grade and thickness specification of the steel to be rolled;

[0049] In this embodiment, the loop is an important part in the steel rolling production process of the rolling mill. Combining with Figure 2Schematic diagram of the mill loop. By adjusting the speeds of adjacent front and rear stands, "extra" rolled pieces are generated between the stands to form and dynamically maintain an arc-shaped loop, that is, the loop. The on-line loop scanner real-time feedbacks the measured loop height, and the loop controller compares it with the set loop height, and then adjusts the speed of the front stand to maintain the loop height unchanged at the given value, realizing the correct speed coordination between the front and rear stands.

[0050] In this embodiment, information such as the steel grade and thickness specification of the steel to be rolled can be obtained manually or automatically by connecting to the production management system. This information will be used as the core basis for subsequent control parameter adjustment to ensure that the loop control strategy matches the steel characteristics.

[0051] Step 102: Dynamically adjust the proportional coefficient and integral time of the loop controller according to the steel grade and thickness specification of the steel to be rolled;

[0052] Specifically, historical rolling data of rolled steel in recent years (for example, historical rolling data in the recent 3 years) can be retrieved from the production database, covering at least 200 sets of different working condition records. Each set of historical rolling data includes the historical steel grade (such as subdivided types of carbon steel, alloy steel, stainless steel, etc.), historical thickness specification (accurate to 0.01 mm), and the proportional coefficient and integral time actually used by the loop controller during the corresponding rolling process. Clean the collected data to eliminate abnormal data caused by sensor failures and operation errors to ensure data accuracy.

[0053] Using clustering algorithms in machine learning (such as K-Means clustering), extract the characteristics of the chemical composition (contents of elements such as carbon, manganese, chromium, etc.) and mechanical properties (yield strength, hardness, etc.) of the historical steel grades, and classify the steel grades into categories such as high-hardness steel grades, medium-hardness steel grades, and soft steels. At the same time, establish interval divisions based on the thickness specification, such as ultra-thin specification (<0.5 mm), thin specification (0.5 - 4 mm), conventional specification (4 - 12 mm), and thick specification (>12 mm).

[0054] Establish a mapping relationship network. Taking the steel grade category and thickness specification interval as the input dimensions and the proportional coefficient and integral time as the output dimensions, construct a multi-dimensional mapping relationship network. Using regression analysis algorithms (such as multiple linear regression, support vector regression), explore the optimal control parameter laws under different combinations of steel grades and thickness specifications. For example, for the rolling data of a certain type of alloy steel in the thickness range of 2 - 4 mm, a mathematical model is obtained through regression analysis that the proportional coefficient is negatively correlated with the thickness and the integral time is positively correlated with the hardness.

[0055] Real-time parameter matching and optimization: After obtaining the steel grade and thickness specification of the steel to be rolled, the system inputs them into the mapping relationship network for matching. If there are completely matching historical data records, the corresponding proportional coefficient and integral time are directly retrieved; if there are no completely matching data, interpolation algorithms (such as bilinear interpolation) are used to estimate the parameter values under the current working conditions based on adjacent data points. At the same time, combining the data such as rolling force, temperature, and speed monitored in real time, the initial parameters are fine-tuned using an adaptive control algorithm. For example, when it is detected that the rolling temperature is 10% lower than the set value, the proportional coefficient is automatically increased by 5%-10% to enhance the response speed of the controller to tension fluctuations.

[0056] Dynamic correction can also be performed for special working conditions, specifically including:

[0057] For the treatment of high-hardness steel grades, that is, for high-hardness steel grades with a Rockwell hardness greater than 30, on the basis of the parameters obtained by matching, the proportional coefficient is additionally increased by 15%-25%, and the integral time is reduced by 20%-30%. By increasing the proportional coefficient, the controller responds more quickly to tension deviations and quickly overcomes the large deformation resistance of high-hardness steel grades; shortening the integral time avoids control lag caused by the accumulation of integral terms and ensures tension stability.

[0058] For the treatment of thin-gauge strip steel, that is, thin-gauge strip steel with a thickness less than 4 mm, the proportional coefficient is reduced by 10%-20% and the integral time is increased by 15%-25% on the basis of the basic parameters. Reducing the proportional coefficient can prevent the thin strip steel from being deformed by pulling and narrowing due to excessive adjustment, and increasing the integral time makes the output of the controller smoother and reduces the influence of tension fluctuations on the thin strip steel.

[0059] In another implementation manner, historical rolling data of historical rolled steel can also be provided, and then according to the historical rolling data of the historical rolled steel, a mapping relationship table of steel grade, thickness specification, proportional coefficient, and integral time is established; the steel grade and thickness specification of the steel to be rolled are obtained in real time, and according to the mapping relationship table, the proportional coefficient and integral time corresponding to the steel grade and specification thickness of the rolled steel are determined and sent to the loop controller.

[0060] Step 103: Adjust the loop angle position and the set reference value of the position loop;

[0061] In this embodiment, the static reference value of the loop angle position can be preset according to the rolling pass and material elongation rate; the strip steel speed difference is obtained in real time; according to the strip steel speed difference, dynamic compensation is performed on the static reference value of the loop angle to achieve the adjustment of the loop angle position; combined with the displacement feedback of the hydraulic loop cylinder, the set reference value of the position loop is corrected to achieve the purpose of adjusting the set reference value of the position loop. Specifically, it can include:

[0062] According to the division of rolling process stages, in the rough rolling stage, considering that the strip steel requires a large amount of deformation, the static reference value of the loop angle position is set in the range of 8 degrees - 12 degrees. This angle range can provide sufficient tension for the strip steel to ensure that the strip steel passes through each stand smoothly during rough rolling and avoid stacking. After entering the finish rolling stage, in order to achieve high-precision shape control, the static reference value of the loop angle is adjusted to 3 degrees - 6 degrees to reduce the tension fluctuation of the strip steel during finish rolling and improve the thickness uniformity of the finished product.

[0063] The material elongation rate of the strip steel is obtained in real time through on-line detection equipment. For steels with a large elongation rate (for example, greater than 25%), in the same rolling pass, the static reference value of the loop angle is appropriately increased by 1 degree - 2 degrees to balance the relaxation trend of the strip steel caused by the high elongation rate; for steels with a small elongation rate (for example, less than 15%), the static reference value of the loop angle is correspondingly reduced by 1 degree - 2 degrees to prevent the strip steel from being narrowed or torn due to excessive tension.

[0064] High-precision speed sensors are installed before and after each stand of the rolling mill equipment, and the sampling frequency is not less than 50Hz to collect the running speed of the strip steel at different positions in real time. By calculating the difference in the strip steel speed between adjacent stands, the strip steel speed difference data is obtained. For example, when the strip steel speed of the upstream stand is 5m / s and the strip steel speed of the downstream stand is 4.8m / s, the speed difference is 0.2m / s.

[0065] A mathematical model of the speed difference and the loop angle compensation amount is established. When the speed difference is positive (the upstream speed is greater than the downstream speed), the following formula is used to calculate the loop angle that needs to be increased:

[0066] Δθ = k1×Δv

[0067] Where, Δθ is the angle compensation amount, k1 is the compensation coefficient, and the value range is 0.5 - 1.0, and Δv is the speed difference.

[0068] When the speed difference is negative, the following formula is used to calculate the loop angle that needs to be reduced:

[0069] Δθ = k2×Δv

[0070] Where, the value range of k2 is -1.0 to -0.5. The compensated loop angle is updated to the control system in real time to ensure the stability of the strip steel tension.

[0071] In one implementation manner, the modification of the position loop setting reference value in combination with the displacement feedback of the hydraulic loop cylinder may include:

[0072] Obtain the real-time displacement data of the hydraulic loop cylinder;

[0073] Calculate the deviation between the displacement data and the target displacement;

[0074] Adjust the proportional coefficient and integral time in the position loop setting reference value according to the deviation and change trend.

[0075] Specifically, use the displacement sensor installed on the hydraulic loop cylinder to collect the real-time displacement data of the hydraulic loop cylinder at a frequency of 100 Hz. Filter the collected data to remove the noise interference caused by factors such as equipment vibration, and ensure the accuracy and reliability of the data.

[0076] Compare the processed real-time displacement data with the target displacement, and calculate the displacement deviation:

[0077] e(t) = y(t) - r(t)

[0078] Where, y(t) is the real-time displacement and r(t) is the target displacement. At the same time, by calculating the deviation change amount Δe(t) = e(t) - e(t - 1) at adjacent moments, analyze the change trend of the deviation.

[0079] According to the magnitude and change trend of the deviation, adopt the adaptive PID control algorithm to adjust the position loop setting reference value. When the deviation |e(t)| > e1, where e1 is the set larger deviation threshold, and Δe(t) has the same sign as e(t), significantly increase the proportional coefficient Kp (the increase range is 15% - 25% of the current value) to accelerate the system response speed; when |e(t)| < e2, where e2 is the set smaller deviation threshold, and Δe(t) approaches 0, appropriately reduce the integral time Ti (the reduction range is 10% - 20% of the current value) to eliminate the static error; dynamically adjust the differential coefficient Kd according to the magnitude of the deviation change rate to enhance the stability of the system.

[0080] Step 104: Optimize the head setting of the threading speed and control the loop height during the head building process.

[0081] In this embodiment, before the head of the steel to be rolled enters the loop, the threading speed can be reduced; after the head of the steel to be rolled passes through each stand, the speed is gradually increased according to a preset gradient; before the head of the steel to be rolled reaches the loop, the loop roll is lifted to a preset height; the height of the loop roll is monitored in real time by a laser rangefinder or an encoder. When the head of the steel to be rolled touches the loop, it is adjusted to the target loop height by the PID algorithm. The preset height is 80% of the target loop height, and the error range of the target loop height is ±10 mm.

[0082] Specifically, when the head of the steel to be rolled is 5 - 8 meters away from the loop entrance, the threading speed is reduced to trigger the low - speed threading mode. At this time, the threading speed is reduced to 50% - 60% of the normal rolling speed (for example, when the normal speed is 6 m / s, the low - speed threading speed is set to 3 - 3.6 m / s). Through the PLC controller of the main drive system, the output frequency of the motor is smoothly reduced using a ramp function to avoid the strip impact caused by sudden speed changes. The speed - down slope is controlled within 0.5 - 1.0 m / s to ensure the smooth entry of the strip head into the loop area.

[0083] During the transition speed - up stage, after the strip head passes through the exit guide device of the upstream stand, the speed is gradually increased at an acceleration of 0.3 - 0.5 m / s². For each 0.5 m / s increase in speed, it is maintained for 1 - 2 seconds to form a stepped acceleration curve. According to the feedback data of the loop tension sensor, the acceleration is adjusted in real - time. When the tension fluctuation exceeds ±5%, the acceleration is paused for 1 second and then continues after the tension stabilizes.

[0084] During the steady - state rolling stage, after the strip head passes through the loop and a stable tension is established, it is accelerated to the normal rolling speed set by the process (error range ±0.2 m / s). Through the load distribution algorithm of the mill main drive system, the speed synchronization rate of each stand is ensured to reach more than 99.8% to avoid loop fluctuations caused by speed asynchronization.

[0085] 0.5 - 1 second before the strip head reaches the loop, the loop roller is pre - lifted to 75% - 80% of the target loop - raising height (for example, when the target height is 500 mm, it is pre - lifted to 375 - 400 mm).

[0086] The lifting speed of the loop hydraulic cylinder is set to 200 - 300 mm / s, and the opening degree of the hydraulic proportional valve is controlled using a PID algorithm to ensure a position accuracy of ±5 mm.

[0087] When the laser rangefinder detects that the distance between the loop roller and the strip surface is less than 20 mm, it is determined that the strip head touches the loop. Immediately after touching the loop, PID closed - loop control is started, and the laser ranging data is read at a sampling frequency of 50 Hz. The control quantity is calculated by the following formula:

[0088] u(t)=Kp×e(t)+Ki×∫0 t e(t)dt+Kd×de(t) / dt

[0089] Among them, the initial value of Kp is 0.8 - 1.2, the initial value of Ki is 0.05 - 0.1, and the initial value of Kd is 0.2 - 0.4, which are adjusted in real - time according to the strip thickness and material.

[0090] Fluctuation suppression: Within 1 - 2 seconds after the strip head passes through the loop, if the loop - raising height fluctuation exceeds ±15 mm, the fuzzy control algorithm is automatically enabled:

[0091] When the fluctuation frequency is greater than 0.5Hz, increase the Kd value by 10%-20%;

[0092] When the fluctuation amplitude is greater than 20 mm, increase the Kp value by 5%-10%.

[0093] Within 3-5 seconds after the strip head passes through the loop, the loop height is locked within the range of ±10mm of the target value and enters the steady-state monitoring mode.

[0094] Regarding abnormal working condition handling:

[0095] Strip warping: When the laser rangefinder detects a strip surface height change rate greater than 50 mm / s at the looper entrance, it is identified as warping. The strip threading speed must be immediately reduced to below 2 m / s, and the looper roller must be quickly raised 20-30 mm to prevent the strip from hitting the looper roller.

[0096] Steel pile prevention control: When the loop angle exceeds the preset value by 15 degrees or the tension suddenly drops by more than 30%, a steel pile warning is triggered. At this time, the upstream frame is urgently braked at a deceleration rate of 1m / s0, and the loop roller is quickly lowered to the lowest position (less than 100mm) to prevent strip accumulation.

[0097] Recovery from threading failure: automatically record the threading failure position and lower the loop roller to the initial position; start the strip head shearing program to cut off the damaged part; reset the threading parameters (reduce the speed by 10%-15%, increase the pre-looping height by 5%-10%) and perform a second threading.

[0098] The above contents, from speed control strategy, height control mechanism, multi-sensor fusion monitoring to abnormal working condition processing, form a complete threading head control system.

[0099] In summary, the embodiments of this specification provide a rolling mill looper control method that obtains the steel grade and thickness specifications of the steel to be rolled; dynamically adjusts the proportional coefficient and integral time of the looper controller based on the steel grade and thickness specifications; adjusts the looper angle position and position loop setting reference value; and optimizes the threading speed head setting to control the looper start height during the head stretching process. Thus, through dynamic parameter adaptation, multi-system coordinated control, and intelligent predictive maintenance, this solution breaks through the bottleneck of traditional looper control's adaptability to steel grades and specifications, significantly improving the precision, efficiency, and stability of hot rolling production, while also laying the foundation for energy consumption optimization and intelligent upgrades.

[0100] Based on the same inventive concept, combined Figure 3 As shown, an embodiment of the present invention further provides a rolling mill looper control device, comprising:

[0101] An acquisition module is used to obtain the steel type and thickness specifications of the steel to be rolled;

[0102] The first adjustment module is used to dynamically adjust the proportional coefficient and integral time of the loop controller according to the steel grade and thickness specification of the steel to be rolled.

[0103] The second adjustment module is used to adjust the loop angle position and the set reference value of the position loop.

[0104] The control module is used to optimize the head setting of the threading speed and control the loop height during the head building tension process.

[0105] Optionally, for high-hardness steel grades with a Rockwell hardness greater than 30, increase the proportional coefficient and decrease the integral time; for thin-gauge strip steel with a thickness less than 4 mm, decrease the proportional coefficient and increase the integral time.

[0106] Optionally, the second adjustment module is further used for:

[0107] Preset the static reference value of the loop angle position according to the rolling pass and material elongation rate.

[0108] Obtain the strip speed difference in real time.

[0109] Dynamically compensate the static reference value of the loop angle according to the strip speed difference.

[0110] Combine the hydraulic loop cylinder displacement feedback to correct the set reference value of the position loop.

[0111] Optionally, the second adjustment module is further used for:

[0112] Obtain the real-time displacement data of the hydraulic loop cylinder.

[0113] Calculate the deviation between the displacement data and the target displacement.

[0114] Adjust the proportional coefficient and integral time in the set reference value of the position loop according to the deviation and the change trend.

[0115] Optionally, the control module is further used for:

[0116] Reduce the threading speed before the head of the steel to be rolled enters the loop.

[0117] After the head of the steel to be rolled passes through each stand, gradually increase the speed according to a preset gradient.

[0118] Lift the loop roll to a preset height before the head of the steel to be rolled reaches the loop.

[0119] Real-time monitor the loop roll height through a laser rangefinder or encoder, and when the head of the steel to be rolled touches the loop, adjust it to the target loop height with a PID algorithm.

[0120] Optionally, the preset height is 80% of the target loop height, and the error range of the target loop height is ±10 mm.

[0121] In summary, a loop control device for a rolling mill provided by an embodiment of this specification obtains the steel type and thickness specification of the steel to be rolled; dynamically adjusts the proportional coefficient and integral time of the loop controller according to the steel type and thickness specification of the steel to be rolled; adjusts the loop angle position and the position loop setting reference value; optimizes the head setting of the threading speed, and controls the loop height during the head tension establishment process. In this way, through dynamic parameter adaptation, multi-system collaborative control, and intelligent predictive maintenance, this solution breaks through the adaptability bottleneck of traditional loop control for steel types and specifications, significantly improves the accuracy, efficiency, and stability of hot rolling production, and at the same time lays a foundation for energy consumption optimization and intelligent upgrading.

[0122] Those skilled in the art can clearly understand that for the convenience and simplicity of description, the specific working process of the above-described loop control device for a rolling mill can refer to the corresponding process in the foregoing method, and will not be elaborated here.

[0123] Based on the same inventive concept, an embodiment of the present invention further provides a controller, which includes a loop control device for a rolling mill, a memory, a processor, and a communication unit. The memory stores machine-readable instructions executable by the processor. When the controller runs, the processor and the memory communicate through a bus. The processor executes the machine-readable instructions and executes the loop control method for a rolling mill.

[0124] The memory, the processor, and the communication unit are electrically connected directly or indirectly to each other to achieve signal transmission or interaction. For example, these components can be electrically connected to each other through one or more communication buses or signal lines. The loop control device for a rolling mill includes at least one software function module that can be stored in the memory in the form of software or firmware. The processor is used to execute the executable module stored in the memory (such as the software function module or computer program included in the loop control device for a rolling mill).

[0125] Among them, the memory can be, but is not limited to, a Random Access Memory (RAM), a Read Only Memory (ROM), a Programmable Read-Only Memory (PROM), an Erasable Programmable Read-Only Memory (EPROM), an Electric Erasable Programmable Read-Only Memory (EEPROM), etc.

[0126] In some embodiments, a processor is used to execute one or more functions described in this embodiment. In some embodiments, the processor may include one or more processing cores (e.g., a single-core processor(s) or a multi-core processor(s)).

[0127] In this embodiment, a memory is used to store a program, and a processor is used to execute the program after receiving an execution instruction. The method defined by the process disclosed in any implementation manner of this embodiment can be applied to or implemented by the processor.

[0128] A communication unit is used to establish a communication connection between the controller and other devices through a network, and is used to transmit and receive data through the network.

[0129] Those skilled in the art can clearly understand that for the convenience and conciseness of description, the specific working process of the controller described above can refer to the corresponding process in the foregoing method, and will not be elaborated herein too much.

[0130] Based on the same inventive concept, an embodiment of the present invention further provides a rolling mill device, characterized in that the rolling mill device includes a rolling mill and a controller installed on the rolling mill, wherein the controller executes the foregoing rolling mill loop control method.

[0131] Those skilled in the art can clearly understand that for the convenience and conciseness of description, the specific working process of the controller of the vehicle described above can refer to the corresponding process in the foregoing method, and will not be elaborated herein too much.

[0132] The above are only various embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, and all should be covered by the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A loop control method for a rolling mill, characterized in that, It includes the following steps: Obtain the steel grade and thickness specification of the steel to be rolled; Dynamically adjust the proportional coefficient and integral time of the loop controller according to the steel grade and thickness specification of the steel to be rolled; Adjust the loop angle position and the set reference value of the position loop; Optimize the head setting of the threading speed and control the loop height during the head building tension process.

2. The loop control method for a rolling mill according to claim 1, characterized in that The dynamically adjusting the proportional coefficient and integral time of the loop controller according to the steel grade and thickness specification includes: Obtain the historical rolling data of the historical rolled steel, where the historical rolling data includes the historical steel grade, historical thickness specification, and the proportional coefficient and integral time corresponding to the historical steel grade and historical thickness specification; Establish a mapping relationship table between the steel grade, thickness specification, proportional coefficient, and integral time according to the historical rolling data of the historical rolled steel; Obtain the steel grade and thickness specification of the steel to be rolled in real time, and determine the proportional coefficient and integral time corresponding to the steel grade and specification thickness of the rolled steel according to the mapping relationship table, and send them to the loop controller for adjustment.

3. The loop control method for a rolling mill according to claim 2, wherein For high-hardness steel grades with Rockwell hardness greater than 30, increase the proportional coefficient and decrease the integral time; for thin-gauge strip steel with a thickness less than 4 mm, decrease the proportional coefficient and increase the integral time.

4. The loop control method for a rolling mill according to claim 1, characterized in that The adjusting the loop angle position and the set reference value of the position loop includes: Preset the static reference value of the loop angle position according to the rolling pass and material elongation; Obtain the strip speed difference in real time; Dynamically compensate the static reference value of the loop angle according to the strip speed difference; Combine the hydraulic loop cylinder displacement feedback to correct the set reference value of the position loop.

5. The loop control method for a rolling mill according to claim 4, characterized in that, The combining the hydraulic loop cylinder displacement feedback to correct the set reference value of the position loop includes: Obtain the real-time displacement data of the hydraulic loop cylinder; Calculate the deviation between the displacement data and the target displacement; Adjust the proportional coefficient and integral time in the set reference value of the position loop according to the deviation and the change trend.

6. The loop control method of the rolling mill according to claim 1, wherein The optimizing the head setting of the threading speed and controlling the loop height during the head building tension process includes: Before the head of the steel to be rolled enters the loop, reduce the threading speed; After the head of the steel to be rolled passes through each stand, gradually increase the speed according to a preset gradient; Before the head of the steel to be rolled reaches the loop, lift the loop roll to a preset height; Real-time monitor the height of the loop roll through a laser rangefinder or encoder, and when the head of the steel to be rolled touches the loop, adjust it to the target loop height with a PID algorithm.

7. The loop control method for a rolling mill according to claim 6, characterized in that, The preset height is 80% of the target loop height, and the error range of the target loop height is ±10 mm.

8. A loop control device for a rolling mill, characterized in that, It includes: An acquisition module for obtaining the steel grade and thickness specification of the steel to be rolled; A first adjustment module for dynamically adjusting the proportional coefficient and integral time of the loop controller according to the steel grade and thickness specification of the steel to be rolled; A second adjustment module for adjusting the loop angle position and the set reference value of the position loop; A control module for optimizing the head setting of the threading speed and controlling the loop height during the head building tension process.

9. A controller, characterized in that, The controller includes: a memory, a processor, and a computer program stored on the memory and executable on the processor, and when the processor executes the computer program, it implements the mill loop control method according to any one of claims 1-7.

10. A rolling mill device, characterized in that, The mill equipment includes a mill and a controller installed on the mill, wherein the controller executes the mill loop control method according to any one of claims 1-7.

Images