Hot rolled strip finishing mill roll gap leveling method based on sample library self-learning
Through the self-learning method of the sample library, the leveling value of the hot-rolled plate and strip finishing mill rolling mill is automatically calculated, which solves the problem of inaccurate manual leveling after the finishing mill is replaced, and improves production stability and plate quality.
Patent Information
- Application Number
- CN202510552742.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-29
- Publication Date
- 2025-08-01
AI Technical Summary
In the prior art, after the rolling rolling mill is replaced, the roll joint leveling depends on manual experience, resulting in poor production stability and unstable rolling line position, which affects the surface quality and dimensional accuracy of the hot-rolled strip.
Using a self-learning method based on the sample library, a sample library of supporting rollers, working rollers and step pads is established by obtaining the characteristic values of the fifth strip steel after the roll replacement, and the roller seam leveling value is automatically calculated to reduce manual adjustments and improve production stability.
Automatic roll joint leveling without manual experience is achieved, the production stability of the finish rolling and opening stage is improved, the risk of strip steel running away from scrap steel is reduced, and the plate quality and rolling accuracy are improved.
Smart Images
Figure CN120394576A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of metallurgical rolling mill control, and particularly relates to a method for leveling the roll gap of a hot rolling strip finishing mill based on self-learning of a sample library. Background Art
[0002] During the production process of hot rolling strips, roll changing operations need to be carried out after each rolling cycle of the finishing mill. After each roll change, due to reasons such as changes in roll diameter and gaps in rolling mill equipment, operators need to calibrate the roll gap of the finishing mill as the reference value of the zero roll gap. After the roll gap calibration is completed, for the first few strips produced, the operator will manually adjust the roll gap inclination value according to the threading deviation of the strip, that is, the manual adjustment amount.
[0003] During the production process of hot rolling strips, the rolls are in direct contact with the hot rolling strips and generate friction, resulting in gradual wear on the roll surface; the surface of the over-worn rolls will lose luster and even show phenomena such as cracking and fatigue, which will reduce the production stability during the rolling process; at the same time, the wear of the rolls will cause changes in the roll profile curve on the roll surface, directly affecting the surface quality and dimensional accuracy of the hot rolling strips. In order to ensure the production quality and efficiency of the hot rolling strips, the rolls need to be replaced regularly.
[0004] When the finishing mill is in normal production, it is necessary to maintain a stable and unchanged rolling line so that the strip is always rolled at the same horizontal height. However, after replacing the rolls of the rolling mill, the position of the rolling line will be affected, so it is necessary to readjust the rolling line to the original position. Roll gap calibration can provide a scale and reference for rolling line adjustment, ensuring that the roll gap of the rolling mill is on the same horizontal line relative to the zero point, thereby ensuring the stability of the rolling line.
[0005] After the roll change is completed, the finishing mill controls the hydraulic cylinder to extend through the control system, so that the upper and lower working rolls are in contact, and the rolling force on the operating side and the driving side is adjusted to be basically balanced. Then, the rolling force is increased by further pressing down. When the sum of the rolling forces on both sides reaches 1000 - 1500 tons, record the extension amount of the hydraulic cylinders on both sides at this time, which is the extension amount of the hydraulic cylinders under the zero roll gap. However, due to the gaps in the assembly of the rolls and the bearing seats, and the oil stains on the surface of the stepped pads, etc., there will be deviations in the zero adjustment of the roll gap, and manual adjustment based on experience according to the threading situation of the first few strips before rolling is required.
[0006] From the above analysis, it can be seen that after the roll change of the finishing mill, the change of the roll system has a direct impact on production stability. The more accurate the recommended value of roll gap leveling is, the less the manual adjustment amount is, and the lower the production stability degree brought by the uncertainty of manual experience is.
[0007] At present, the preset roll gap of the finishing mill in the 2250 hot strip mill is mainly pre-adjusted by the operator according to the previous roll gap experience after the zero adjustment of the finishing mill to achieve the stability of passing steel. When manually exploring parameters, due to the limitation of human memory, only the recent parameters can be compared, and all the parameters of passing steel in the previous period cannot be compared. Therefore, there are problems such as unreasonable setting parameters, poor passing steel stability, and uncontrollable plate shape. Therefore, a roll gap leveling method for the finishing mill of hot rolled strip based on self-learning of the sample library is designed to solve the problem that the leveling of the finishing roll gap in the existing technology depends on manual labor. Summary of the Invention
[0008] Aiming at the problems existing in the prior art, the purpose of the present invention is to provide a roll gap leveling method for the finishing mill of hot rolled strip based on self-learning of the sample library.
[0009] The technical solution adopted by the present invention to solve its technical problems is: a roll gap leveling method for the finishing mill of hot rolled strip based on self-learning of the sample library, including the following steps:
[0010] S1. Obtain the rolling characteristic values of the 5th strip produced after roll change, including roll matching information: backup roll housing number, work roll housing number; roll change adjustment information: upper step pad number, lower step pad number; operation intervention characteristics: inclination of the cylinder in the stable state.
[0011] S2. According to the calculated characteristic values, the sample library of the current rolling mill is divided into a backup roll sample library, a work roll sample library, and a step pad sample library.
[0012] S3. After the zero adjustment and calibration of the rolling mill roll gap are completed, automatically select the sample library of the rolling mill according to the current roll matching information and roll change adjustment information of the rolling mill.
[0013] S4. Thus, the three sub-sample libraries jointly constitute the self-learning sample library for leveling recommendation of the current rolling mill. The number of samples in the backup roll sample library is M1, the number of samples in the step pad sample library is M2, and the number of samples in the work roll sample library is M3.
[0014] S5. According to the self-learning sample library for leveling recommendation, calculate the average value of the inclination of the cylinder in the stable state corresponding to the three sub-sample libraries, and its data expression is:
[0015]
[0016] S6. The recommended manual inclination adjustment value of the current rolling mill is Δlevel = Δh - Δh0.
[0017] Specifically, the backup roll housing number, work roll housing number, upper step pad number, and lower step pad number in step S1 are the data corresponding to the rolling mill at the moment of rolling the current strip.
[0018] Specifically, the inclination of the cylinder in the steady state in step S1 is the average value of the difference in the cylinder extension amounts from the 4th second to the 6th second after the current strip is bitten during rolling. The specific mathematical expression process is as follows:
[0019] h = (H WS - H DS ) avg ;
[0020] h represents the average inclination value of the cylinder extension amount of the current rolling mill;
[0021] H WS represents the extension amount of the screw-down cylinder on the operator side of the current rolling mill;
[0022] H DS represents the extension amount of the screw-down cylinder on the drive side of the current rolling mill.
[0023] Specifically, the support roll sample in step S2 includes the upper support roll box number, the lower support roll box number, and the inclination of the cylinder in the steady state;
[0024] The work roll sample includes the upper work roll box number, the lower work roll box number, and the inclination of the cylinder in the steady state;
[0025] The stepped pad sample includes the upper stepped pad number, the lower stepped pad number, and the inclination of the cylinder in the steady state.
[0026] Specifically, the sample library for automatically selecting a rolling mill in step S3 is to automatically select the support roll sample, work roll sample, and stepped pad sample with the same upper support roll box number, lower support roll box number, upper work roll box number, lower work roll box number, upper stepped data, and lower stepped data of the current rolling mill.
[0027] Specifically, in step S4, M1 support roll samples are selected from the leveling recommendation self-learning sample library. Priority is given to selecting the M1 samples with the latest data time. If there are only N1 samples and N1 < M1, then the number of samples to be added in the stepped pad sample number is M1 - N1;
[0028] M2 stepped pad samples are selected. Priority is given to selecting the M2 samples with the latest data time. If there are only N2 samples and N2 < M2, then the number of samples to be added in the work roll sample number is M2 - N2;
[0029] M3 work roll samples are selected. Priority is given to selecting the M3 samples with the latest data time. If there are only N3 samples and N3 < M3, then only N3 samples are selected, and N3 ≤ M3.
[0030] Specifically, in the data expression in step S5:
[0031] Δh represents the recommended value of the inclination of the cylinder extension of the current rolling mill;
[0032] h BUR represents the cylinder extension of the backup roll sample of the current rolling mill;
[0033] H WR represents the cylinder extension of the work roll sample of the current rolling mill;
[0034] H STEP represents the cylinder extension of the step pad sample of the current rolling mill;
[0035] where α, β, and γ are the influence factors of the backup roll, work roll, and step pad, and α + β + γ = 1;
[0036] The influence factors α, β, and γ of the backup roll, work roll, and step pad allow manual adjustment.
[0037] Specifically, in the formula of step S6:
[0038] Δlevel represents the recommended value of the manual inclination adjustment amount;
[0039] Δh0 represents the inclination amount of the cylinder extensions on both sides when the zero adjustment calibration of the current rolling mill is completed.
[0040] The present invention has the following beneficial effects:
[0041] The method for leveling the roll gap of the hot-rolled strip finishing mill based on self-learning of the sample library designed by the present invention obtains the characteristic values of each strip production, establishes the sample library of the current rolling mill, and automatically recommends the optimal roll gap leveling value through self-learning, without relying on manual experience adjustment, improving the production stability in the finishing rolling start stage, reducing the risk of strip deviation and scrap, improving the strip shape quality, and avoiding the quality objection of waviness. BRIEF DESCRIPTION OF THE DRAWINGS
[0042] Figure 1 It is a schematic diagram for collecting the sample library of the hot-rolled strip finishing mill according to the embodiment of the present invention.
[0043] Figure 2 It is a schematic diagram of the steps for leveling the roll gap of the hot-rolled strip finishing mill according to the embodiment of the present invention.
[0044] Figure 3 It is a schematic diagram of the final output screen of the present invention. DETAILED DESCRIPTION OF THE INVENTION
[0045] The following will further clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the 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 protection scope of the present invention.
[0046] As shown Figures 1 - 3 in the figure, a method for leveling the roll gap of a hot rolling strip finishing mill based on self-learning of a sample library includes the following steps:
[0047] 1. Obtain the rolling characteristic values of the 5th strip produced after roll change, including roll matching information: backup roll housing number, work roll housing number; roll change adjustment information: upper step pad number, lower step pad number; operation intervention feature: cylinder tilt amount in the stable state.
[0048] The backup roll housing number, work roll housing number; the roll change adjustment information: upper step pad number, lower step pad number are the data corresponding to the rolling mill at the current strip rolling time.
[0049] The cylinder tilt amount in the stable state is the average value of the difference in the cylinder extension amount from the 4th second to the 6th second after the current strip is bitten during rolling. The specific mathematical expression process is as follows:
[0050] h = (H WS - H DS ) avg ; h represents the average tilt value of the cylinder extension amount of the current rolling mill; H WS represents the cylinder extension amount of the current rolling mill on the operator side; H DS represents the cylinder extension amount of the current rolling mill on the drive side.
[0051] 2. According to the calculated characteristic values, the sample library of the current rolling mill is divided into a backup roll sample library, a work roll sample library, and a step pad sample library; the backup roll samples include the upper backup roll housing number, lower backup roll housing number, and cylinder tilt amount in the stable state; the work roll samples include the upper work roll housing number, lower work roll housing number, and cylinder tilt amount in the stable state; the step pad samples include the upper step pad number, lower step pad number, and cylinder tilt amount in the stable state.
[0052] 3. After the zero adjustment calibration of the rolling mill roll gap is completed, automatically select the sample library of the rolling mill according to the roll matching information and roll change adjustment information of the current rolling mill; automatically selecting the sample library of the rolling mill is to automatically select the backup roll samples, work roll samples, and step pad samples with the same upper backup roll housing number, lower backup roll housing number, upper work roll housing number, lower work roll housing number, upper step data, and lower step data of the current rolling mill.
[0053] 4. These three sub-sample libraries together constitute the self-learning sample library for leveling recommendation of the current rolling mill. The number of samples in the backup roll sample library is M1, the number of samples in the step pad sample library is M2, and the number of samples in the work roll sample library is M3.
[0054] Select M1 support roller samples from the leveling recommended self-learning sample library. Preferentially select the M1 samples with the latest data time. If there are only N1 samples and N1 < M1, then increase the number of samples in the step pad samples by the difference M1 - N1.
[0055] Select M2 step pad samples. Preferentially select the M2 samples with the latest data time. If there are only N2 samples and N2 < M2, then increase the number of samples in the work roll samples by the difference M2 - N2.
[0056] Select M3 work roll samples. Preferentially select the M3 samples with the latest data time. If there are only N3 samples and N3 < M3, then only select N3 samples, and N3 ≤ M3.
[0057] 5. According to the leveling recommended self-learning sample library, calculate the average value of the stable state cylinder tilt of the three sub-sample libraries. Its data expression is:
[0058]
[0059] In the formula: Δh represents the recommended value of the cylinder extension tilt of the current rolling mill; h BUR represents the cylinder extension of the support roller sample of the current rolling mill; H WR represents the cylinder extension of the work roll sample of the current rolling mill; H STEP represents the cylinder extension of the step pad sample of the current rolling mill; where α, β, and γ are the influence factors of the support roller, work roll, and step pad, and α + β + γ = 1; the influence factors α, β, and γ of the support roller, work roll, and step pad allow manual adjustment.
[0060] 6. The recommended manual tilt adjustment value of the current rolling mill is Δlevel = Δh - Δh0.
[0061] In the formula: Δlevel represents the recommended value of the manual tilt adjustment amount; Δh0 represents the tilt amount of the cylinder extensions on both sides when the zero adjustment calibration of the current rolling mill is completed. Specific embodiments
[0063] Figure 1 Shown is a schematic diagram of the collection of the hot-rolled strip sample library of the embodiment of the present invention, including:
[0064] When the strip steel enters the rolling process of the rolling mill, collect the current upper support roll box number, lower support roll box number, upper work roll box number, lower work roll box number, upper step pad number, and lower step pad number, and calculate the average value of the roll gap tilt from the 4th second to the 6th second during the current rolling process to form the sample library as shown in Table 1 below.
[0065] Table 1 Sample library.
[0066]
[0067] After each roll change, the production data of the 5th strip is automatically recorded into the sample library. And it is classified according to backup rolls, work rolls, and stepped pads to form a backup roll sample library, a work roll sample library, and a stepped pad sample library. As shown in Table 2 below.
[0068] Table 2 Backup roll sample library.
[0069]
[0070]
[0071] The work roll sample library and the stepped pad sample library are similar.
[0072] After the mill calibration is completed, the data in the same sub-sample library is automatically screened according to the current roll system data. For example, after the zero adjustment of the current F1 mill is completed, the roll gap inclination of the zero adjustment calibration is -0.32 mm, and the current roll system data is:
[0073] Upper backup roll: ZYZ-39;
[0074] Upper work roll: G50000;
[0075] Lower work roll: G50007;
[0076] Lower backup roll: ZYZ-12;
[0077] Upper stepped pad: 2;
[0078] Lower stepped pad: 3;
[0079] Assume that the determined number of backup roll samples, work roll samples, and stepped pad samples are 7, 4, and 3 respectively.
[0080] According to the sample quantity, the historical cylinder inclination data with the same box number as the current backup roll is automatically screened as: -0.82 mm, -0.98 mm, -0.85 mm, -0.92 mm, -0.72 mm, -0.97 mm, -0.64 mm.
[0081] According to the sample quantity, the historical cylinder inclination data with the same box number as the current work roll is automatically screened as: -0.72 mm, -0.69 mm, -0.54 mm, -0.26 mm.
[0082] According to the sample quantity, the historical cylinder inclination data with the same pad number as the current stepped pad is automatically screened as: -0.82 mm, -0.81 mm, -0.83 mm.
[0083] Then calculate the recommended value of the cylinder inclination of the current mill as
[0084]
[0085] Then the recommended manual adjustment amount is -0.78 - (-0.32) = -0.46 mm.
[0086] In summary, the present solution has the following characteristics: 1. The recommended leveling accuracy keeps getting higher. It continuously learns based on the current sample library of the rolling mill itself. As production progresses, the number of the sample library increases, and the recommended accuracy becomes higher and higher; 2. It has a wide range of applications and can be applied to hot-rolled strip production lines with any number of rolling mills. After manual calibration is completed, the system automatically calculates the recommended roll gap leveling value, which not only ensures the continuity of production but also ensures the stability of the strip steel at the initial rolling stage, improves the rolling accuracy, and guarantees the product quality.
[0087] The present invention is not limited to the above embodiments. Anyone should know that structural changes made under the inspiration of the present invention, as long as they have the same or similar technical solutions as the present invention, all fall within the protection scope of the present invention.
[0088] The technologies, shapes, and structures not described in detail in the present invention are all well-known technologies.
Claims
1. A roll gap leveling method for a hot rolling strip finishing mill based on self-learning of a sample library, characterized in that It includes the following steps: S1. Obtain the rolling characteristic values of the 5th strip produced after roll change, including roll matching information: backup roll housing number, work roll housing number; roll change adjustment information: upper step pad number, lower step pad number; operation intervention feature: inclination of the cylinder in the stable state; S2. According to the calculated characteristic values, the sample library of the current rolling mill is divided into a backup roll sample library, a work roll sample library, and a step pad sample library; S3. After the zero adjustment calibration of the rolling mill roll gap is completed, automatically select the sample library of the rolling mill according to the roll matching information and roll change adjustment information of the current rolling mill; S4. Thus, the three sub-sample libraries jointly constitute the self-learning sample library for leveling recommendation of the current rolling mill. The number of samples in the backup roll sample library is M1, the number of samples in the step pad sample library is M2, and the number of samples in the work roll sample library is M3; S5. According to the self-learning sample library for leveling recommendation, calculate the average value of the inclination of the cylinder in the stable state corresponding to the three sub-sample libraries, and its data expression is: S6. The recommended manual inclination adjustment value for the current rolling mill is Δlevel = Δh - Δh0.
2. The method for roll gap leveling of a hot rolling strip finishing mill based on self-learning from a sample library according to claim 1, characterized in that The backup roll housing number, work roll housing number, upper step pad number, and lower step pad number in step S1 are the data corresponding to the rolling mill at the moment of the current rolled strip.
3. The roll gap leveling method for the finishing mill of hot rolled strip based on self-learning from a sample library according to claim 1, characterized in that, The inclination of the cylinder in the stable state in step S1 is the average value of the difference in the cylinder extension amount from the 4th second to the 6th second after the current strip is bitten during rolling. The specific mathematical expression process is: h = (H WS - H DS ) avg ; h represents the average inclination value of the cylinder extension amount of the current rolling mill; H WS Indicates the extension amount of the screwdown cylinder on the operator side of the current rolling mill; H DS Indicates the extension of the screwdown cylinder on the drive side of the current rolling mill.
4. The method for leveling the roll gap of the finishing mill of hot-rolled strip based on self-learning of the sample library according to claim 1, characterized in that, The backup roll samples in step S2 include the upper backup roll housing number, lower backup roll housing number, and inclination of the cylinder in the stable state; The work roll samples include the upper work roll housing number, lower work roll housing number, and inclination of the cylinder in the stable state; The step pad samples include the upper step pad number, lower step pad number, and inclination of the cylinder in the stable state.
5. The method for leveling the roll gap of the finishing mill of hot-rolled strip based on self-learning from a sample library according to claim 4, characterized in that, The automatic selection of the sample library of the rolling mill in step S3 is to automatically select the upper backup roll housing number, lower backup roll housing number, upper work roll housing number, lower work roll housing number, upper step data, and lower step data of the current rolling mill that are the same as those in the backup roll samples, work roll samples, and step pad samples.
6. The method for leveling the roll gap of the finishing mill of hot-rolled strip based on self-learning from a sample library according to claim 1, wherein In the self-learning sample library for leveling recommendation in step S4, select M1 backup roll samples, and preferentially select the M1 samples with the latest data time. If there are only N1 samples and N1 < M1, then increase the number of samples in the step pad sample number by the difference M1 - N1; Select M2 step pad samples, and preferentially select the M2 samples with the latest data time. If there are only N2 samples and N2 < M2, then increase the number of samples in the work roll sample number by the difference M2 - N2; Select M3 work roll samples, and preferentially select the M3 samples with the latest data time. If there are only N3 samples and N3 < M3, then only select N3 samples, and N3 ≤ M3.
7. The method for leveling the roll gap of a hot rolling strip finishing mill based on self-learning from a sample library according to claim 1, characterized in that, In the data expression in step S5: Δh represents the inclination recommendation value of the cylinder extension amount of the current rolling mill; h BUR Indicates the extension of the current mill backup roll sample oil cylinder; H WR Indicates the extension of the current rolling mill work roll sample oil cylinder; H STEP Indicates the cylinder extension of the current rolling mill step pad sample; Where αβγ are the influence factors of the backup roll, work roll, and step pad, and α + β + γ = 1; The influence factors αβγ of the backup roll, work roll, and step pad allow manual adjustment.
8. The roll gap leveling method for a hot rolling strip finishing mill based on self-learning from a sample library according to claim 1, characterized in that, In the formula in step S6: Δlevel represents the recommended value of the manual tilt adjustment amount; Δh0 represents the tilt amount of the cylinder extension on both sides when the zero adjustment calibration of the current rolling mill is completed.