A method for controlling roll wear

Abstract

This invention relates to a method for controlling roll wear, belonging to the technical field of hot continuous rolling processes. The technical solution of this invention is as follows: collecting characteristic parameters of a four-high rolling mill; collecting performance and dimensional parameters of typical strip steel during rolling; setting initial roll profile parameters for the CVC work rolls; establishing a comprehensive objective function model for controlling strip exit shape and roll wear; optimizing the work roll profile parameters and outputting optimal parameter values. The beneficial effects of this invention are: minimizing roll wear while ensuring actual production, improving strip shape quality, bringing economic benefits to enterprises, and possessing good promotional value.

Description

Technical Field

[0001] This invention relates to a method for controlling roll wear, belonging to the technical field of hot continuous rolling methods. Background Technology

[0002] In recent years, with the continuous development of the steel industry and the continuous progress of rolling technology, the steel industry has occupied a pivotal position in the national economy. At the same time, customers' requirements for strip steel products are constantly increasing, especially in the fields of household appliances, aerospace, automobiles and ships, where the requirements for strip steel quality are more stringent. Among the quality of strip steel products, the strip shape quality is a key focus and challenge in production. Therefore, in order to meet the requirements of export products, a larger rolling process is often required during the hot rolling process of strip steel, which causes rapid wear of the rolls during operation. This not only has an adverse effect on strip shape control, but also increases production costs, which is not conducive to the economic development of enterprises.

[0003] During the hot rolling process, the strip exit shape depends on the roll gap shape between the work rolls. The work rolls are affected by bending forces and rolling forces, resulting in varying degrees of deformation during operation, which adversely affects strip shape control. Simultaneously, due to uneven distribution of inter-roll pressure and rolling pressure, the work rolls experience varying degrees of wear, leading to irregular wear of the work roll shape and affecting the roll gap shape, resulting in poor strip exit shape. Therefore, it is necessary to address work roll wear and strip shape control to improve strip product quality. Currently, according to literature reviews, many domestic and international studies use the influence function method to hypothesize and analyze the influencing factors of strip exit shape, studying the impact of each factor on shape control. However, the calculation results have significant errors compared to actual production requirements. Alternatively, the finite element method is used to analyze the rolling mill mechanism and strip as a whole, studying the control characteristics of the rolling equipment on strip shape. However, this method is complex, inefficient, and difficult to meet actual production requirements. Summary of the Invention

[0004] The purpose of this invention is to provide a method for controlling roll consumption. Taking into account the equipment characteristics of the rolling mill, this method studies the influence of CVC work roll profile changes on inter-roll pressure and rolling pressure distribution, establishes a comprehensive control model for roll consumption and strip shape, and optimizes new roll profile parameters. While ensuring actual production, this method minimizes roll consumption, improves strip shape quality, and brings economic benefits to enterprises. It has good promotional value and effectively solves the aforementioned problems existing in the background technology.

[0005] The technical solution of the present invention is: a method for controlling roll wear, comprising the following steps:

[0006] S1. Collect equipment characteristic parameters of the four-roll mill unit;

[0007] S2. Collect the performance and dimensional parameters of typical strip steel during the rolling process;

[0008] S3. Set the initial roll profile parameters for the CVC work roll;

[0009] S4. Establish a comprehensive control objective function model for strip steel exit shape and roll wear;

[0010] S5. Optimize the working roll profile parameters and output the optimal parameter values.

[0011] In step S1, the equipment characteristic parameters of the four-roll mill unit are collected, including total rolling pressure, support force, bending force, diameter of CVC work roll at axial displacement, maximum and minimum values ​​of the maximum diameter difference of CVC work roll, maximum and minimum values ​​of the distance between the maximum and minimum radius sections of CVC work roll, support roll diameter, CVC work roll length, and support roll length.

[0012] In step S2, typical strip steel performance and dimensional parameters during the rolling process are collected, including strip steel width, strip steel thickness, strip steel elastic modulus and Poisson's ratio, and strip steel deformation resistance.

[0013] In step S3, the initial roll profile parameters of the CVC working roll are set, including the CVC working roll profile optimization parameters, as well as the optimization step size and initial number of optimizations for the CVC working roll profile optimization parameters; the CVC working roll profile optimization parameters include the maximum roll diameter difference of the CVC working roll and the distance between the maximum diameter section and the minimum diameter section of the CVC working roll.

[0014] The specific steps in step S4 include:

[0015] S4.1 Calculate the initial roll profile D of the CVC work roll. g :

[0016]

[0017] Among them, D c y is the radius of the CVC working roll when y = ε, ΔD is the maximum diameter difference of the CVC working roll, s is the distance between the maximum diameter section and the minimum diameter section of the CVC working roll, ε is the axial displacement of the CVC working roll, and y is the corresponding number of working roll units;

[0018] S4.2 Calculate the pressure distribution between the CVC work roll and the support roll and the rolling pressure distribution between the CVC work roll and the strip steel under different incoming material specifications;

[0019] S4.3 Establish the objective function for CVC work roll wear control:

[0020] Based on the calculated pressure distribution between the CVC work roll and support roll under different incoming material specifications, the objective function N1(X) for controlling the pressure distribution between the CVC work roll and support roll under different incoming material specifications is calculated.

[0021]

[0022] Among them, N1(X) i ) is the objective function for controlling the pressure distribution between the CVC work roll and support roll corresponding to the i-th strip specification, n is the total number of typical strip specifications, λ is the control coefficient for the pressure distribution between the CVC work roll and support roll, M is the total number of units bisected by the CVC work roll, and Y c (y) represents the pressure distribution between the CVC work roll and the support roll. It is the average pressure between the CVC work roll and the support roll;

[0023] Based on the calculated rolling pressure distribution between the CVC work roll and the strip, the objective function N2(X) for controlling the rolling pressure distribution between the CVC work roll and the strip under different incoming material specifications is calculated:

[0024]

[0025] Among them, N2(X) i ) is the objective function for controlling the rolling pressure distribution between the CVC work roll and the strip of the i-th type of strip, γ is the control coefficient for the rolling pressure distribution between the CVC work roll and the strip, N is the total number of units bisected by the strip, and F c (y) represents the rolling pressure distribution between the CVC work roll and the strip. It is the average rolling pressure between the CVC work roll and the strip;

[0026] Based on the calculated objective function N1(X) for controlling the pressure distribution between the CVC work roll and the support roll, and the objective function N2(X) for controlling the rolling pressure distribution between the CVC work roll and the strip, the objective function G1(X) for controlling the roll wear of the CVC work roll is calculated:

[0027] G1(X)=κN1(X)+(1-κ)N2(X)

[0028] Where κ is the weighting coefficient;

[0029] S4.4 Calculate the CVC work roll deflection and strip exit thickness distribution;

[0030] S4.5 Calculate the tension distribution and strip shape distribution before the strip exits;

[0031] S4.6 Establish the objective function for controlling the strip shape at the exit:

[0032]

[0033] Among them, G2(X) i ) is the objective function for controlling the strip shape at the exit of the i-th type of strip, ω is the strip shape control coefficient at the exit of the strip, and I y It is the strip steel export plate shape distribution, I max It is the maximum value of the strip steel export shape, I min It is the minimum value of the strip steel export shape;

[0034] S4.7 Establish a comprehensive control objective function that combines control of CVC work roll wear and strip exit shape.

[0035] G(X) = αG1(X) + βG2(X)

[0036] Where α and β are weighting coefficients.

[0037] In step S5, based on the established comprehensive control objective function G(X) for controlling both CVC work roll wear and strip exit shape, and in conjunction with relevant equipment and strip parameters, the comprehensive control objective function G(X) for controlling both CVC work roll wear and strip exit shape is calculated. Specific steps include:

[0038] Determine whether the Powell condition holds, i.e., calculate a certain objective function G. j (X) and the next objective function G j+1 Does (X) exist? If the condition is met, the optimization ends; otherwise, update the parameters of the maximum roll diameter difference of the CVC working roll and the distance between the maximum and minimum diameter sections of the CVC working roll, and continue the optimization.

[0039] Based on the optimization results, the optimal solution for the CVC work roll profile curve parameters is obtained, and the optimal values ​​of the CVC work roll profile curve parameters are output.

[0040] The optimal values ​​of the output CVC work roll profile curve parameters are used to update the maximum roll diameter difference of the CVC work roll and the distance between the maximum and minimum diameter sections of the CVC work roll. Specifically:

[0041]

[0042] Where, ΔD min It is the minimum difference between the maximum and minimum diameters of the CVC work rolls, ΔD max It is the maximum difference in diameter between the CVC work rolls, s min It is the minimum distance between the maximum and minimum diameter sections of the CVC work roll, s maxV(ΔD,s) is the maximum distance between the maximum and minimum diameter sections of the CVC work roll, and V(ΔD,s) is the combination of the maximum roll diameter difference of the CVC work roll and the distance between the maximum and minimum diameter sections of the CVC work roll. min (ΔD,s) is the minimum value of the optimization variables for the maximum roll diameter difference of the CVC working roll and the distance between the maximum and minimum diameter sections of the CVC working roll, k is the number of optimizations, and Δν(ΔD,s) is the optimization step size for the optimization variables for the maximum roll diameter difference of the CVC working roll and the distance between the maximum and minimum diameter sections of the CVC working roll.

[0043] The beneficial effects of this invention are: by comprehensively considering the equipment characteristics of the rolling mill unit, and by studying the influence of CVC work roll profile changes on the distribution of inter-roll pressure and rolling pressure, a comprehensive control model for roll consumption and plate shape is established, and new roll profile parameters are optimized. On the basis of ensuring actual production, roll consumption is minimized to the greatest extent, plate shape quality is improved, and economic benefits are brought to enterprise production. It has good promotion value. Attached Figure Description

[0044] Figure 1 This is the overall flowchart of the present invention;

[0045] Figure 2 This is a schematic diagram of the CVC roller profile curve of the present invention. Detailed Implementation

[0046] To make the purpose, technical solutions, and advantages of the invention's embodiments clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described are only a small part of the embodiments of the present invention, not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the protection scope of the present invention.

[0047] A method for controlling roll wear includes the following steps:

[0048] S1. Collect equipment characteristic parameters of the four-roll mill unit;

[0049] S2. Collect the performance and dimensional parameters of typical strip steel during the rolling process;

[0050] S3. Set the initial roll profile parameters for the CVC work roll;

[0051] S4. Establish a comprehensive control objective function model for strip steel exit shape and roll wear;

[0052] S5. Optimize the working roll profile parameters and output the optimal parameter values.

[0053] In step S1, the equipment characteristic parameters of the four-roll mill unit are collected, including total rolling pressure, support force, bending force, diameter of CVC work roll at axial displacement, maximum and minimum values ​​of the maximum diameter difference of CVC work roll, maximum and minimum values ​​of the distance between the maximum and minimum radius sections of CVC work roll, support roll diameter, CVC work roll length, and support roll length.

[0054] In step S2, typical strip steel performance and dimensional parameters during the rolling process are collected, including strip steel width, strip steel thickness, strip steel elastic modulus and Poisson's ratio, and strip steel deformation resistance.

[0055] In step S3, the initial roll profile parameters of the CVC working roll are set, including the CVC working roll profile optimization parameters, as well as the optimization step size and initial number of optimizations for the CVC working roll profile optimization parameters; the CVC working roll profile optimization parameters include the maximum roll diameter difference of the CVC working roll and the distance between the maximum diameter section and the minimum diameter section of the CVC working roll.

[0056] The specific steps in step S4 include:

[0057] S4.1 Calculate the initial roll profile D of the CVC work roll. g :

[0058]

[0059] Among them, D c y is the radius of the CVC working roll when y = ε, ΔD is the maximum diameter difference of the CVC working roll, s is the distance between the maximum diameter section and the minimum diameter section of the CVC working roll, ε is the axial displacement of the CVC working roll, and y is the corresponding number of working roll units;

[0060] S4.2 Calculate the pressure distribution between the CVC work roll and the support roll and the rolling pressure distribution between the CVC work roll and the strip steel under different incoming material specifications;

[0061] S4.3 Establish the objective function for CVC work roll wear control:

[0062] Based on the calculated pressure distribution between the CVC work roll and support roll under different incoming material specifications, the objective function N1(X) for controlling the pressure distribution between the CVC work roll and support roll under different incoming material specifications is calculated.

[0063]

[0064] Among them, N1(X) i) is the objective function for controlling the pressure distribution between the CVC work roll and support roll corresponding to the i-th strip specification, n is the total number of typical strip specifications, λ is the control coefficient for the pressure distribution between the CVC work roll and support roll, M is the total number of units bisected by the CVC work roll, and Y c (y) represents the pressure distribution between the CVC work roll and the support roll. It is the average pressure between the CVC work roll and the support roll;

[0065] Based on the calculated rolling pressure distribution between the CVC work roll and the strip, the objective function N2(X) for controlling the rolling pressure distribution between the CVC work roll and the strip under different incoming material specifications is calculated:

[0066]

[0067] Among them, N2(X) i ) is the objective function for controlling the rolling pressure distribution between the CVC work roll and the strip of the i-th type of strip, γ is the control coefficient for the rolling pressure distribution between the CVC work roll and the strip, N is the total number of units bisected by the strip, and F c (y) represents the rolling pressure distribution between the CVC work roll and the strip. It is the average rolling pressure between the CVC work roll and the strip;

[0068] Based on the calculated objective function N1(X) for controlling the pressure distribution between the CVC work roll and the support roll, and the objective function N2(X) for controlling the rolling pressure distribution between the CVC work roll and the strip, the objective function G1(X) for controlling the roll wear of the CVC work roll is calculated:

[0069] G1(X)=κN1(X)+(1-κ)N2(X)

[0070] Where κ is the weighting coefficient;

[0071] S4.4 Calculate the CVC work roll deflection and strip exit thickness distribution;

[0072] S4.5 Calculate the tension distribution and strip shape distribution before the strip exits;

[0073] S4.6 Establish the objective function for controlling the strip shape at the exit:

[0074]

[0075] Among them, G2(X) i ) is the objective function for controlling the strip shape at the exit of the i-th type of strip, ω is the strip shape control coefficient at the exit of the strip, and I y It is the strip steel export plate shape distribution, I max It is the maximum value of the strip steel export shape, I min It is the minimum value of the strip steel export shape;

[0076] S4.7 Establish a comprehensive control objective function that combines control of CVC work roll wear and strip exit shape.

[0077] G(X) = αG1(X) + βG2(X)

[0078] Where α and β are weighting coefficients.

[0079] In step S5, the roll profile parameters of the work roll are optimized, and the optimal parameter values ​​are output. Specific steps include:

[0080] Determine whether the Powell condition holds, i.e., calculate a certain objective function G. j (X) and the next objective function G j+1 Does (X) exist? If the condition is met, the optimization ends; otherwise, update the parameters of the maximum roll diameter difference of the CVC working roll and the distance between the maximum and minimum diameter sections of the CVC working roll, and continue the optimization.

[0081] Based on the optimization results, the optimal solution for the CVC work roll profile curve parameters is obtained, and the optimal values ​​of the CVC work roll profile curve parameters are output.

[0082] The optimal values ​​of the output CVC work roll profile curve parameters are used to update the maximum roll diameter difference of the CVC work roll and the distance between the maximum and minimum diameter sections of the CVC work roll. Specifically:

[0083]

[0084] Where, ΔD min It is the minimum difference between the maximum and minimum diameters of the CVC work rolls, ΔD max It is the maximum difference in diameter between the CVC work rolls, s min It is the minimum distance between the maximum and minimum diameter sections of the CVC work roll, s max V(ΔD,s) is the maximum distance between the maximum and minimum diameter sections of the CVC work roll, and V(ΔD,s) is the combination of the maximum roll diameter difference of the CVC work roll and the distance between the maximum and minimum diameter sections of the CVC work roll. min (ΔD,s) is the minimum value of the optimization variables for the maximum roll diameter difference of the CVC working roll and the distance between the maximum and minimum diameter sections of the CVC working roll, k is the number of optimizations, and Δν(ΔD,s) is the optimization step size for the optimization variables for the maximum roll diameter difference of the CVC working roll and the distance between the maximum and minimum diameter sections of the CVC working roll.

[0085] Example 1:

[0086] like Figure 1 The present invention includes the following steps:

[0087] S1. Collect equipment characteristic parameters of the four-roll mill unit;

[0088] S2. Collect typical strip steel performance and dimensional parameters during the rolling process;

[0089] S3. Set the initial roll profile parameters for the CVC work roll;

[0090] S4. Establish a comprehensive control objective function model for strip steel exit shape and roll wear;

[0091] S5. Optimize the working roll profile parameters and output the optimal parameter values.

[0092] Specifically, it includes:

[0093] The main equipment characteristic parameters collected for the four-roll mill unit include total rolling pressure, support force 1400t, bending force 80t, radius of axial displacement of CVC work roll 900mm, maximum and minimum difference in maximum roll diameter of CVC work roll 18mm and 8mm, maximum and minimum distance between maximum and minimum radius sections of CVC work roll 1200mm and 800mm, support roll diameter 1400mm, CVC work roll length 2000mm, and support roll length 1800mm.

[0094] The main performance and dimensional parameters of typical strip steel collected during the rolling process include: typical strip steel width [800, 900, 1000, 1100, 1200, 1300, 1400] mm; typical strip steel average incoming thickness [17.85, 18.15, 18.44, 18.96, 19.28, 19.87, 21.25] mm; and strip steel elastic modulus 2.1 × 10⁻⁶. 5 MPa and Poisson's ratio 0.3, strip deformation resistance 115MPa;

[0095] Define the roll wear control objective function G1(X), the strip exit shape control objective function G2(X), and the combined strip exit shape and roll wear control objective function G(X);

[0096] The initial roll profile parameters of the CVC working roll are set, mainly including the optimization step size of 1mm and the initial number of optimizations of the CVC working roll roll profile optimization parameters of 0, the initial value of the maximum roll diameter difference of the CVC working roll of 8mm, the maximum roll diameter difference of the CVC working roll and the distance between the maximum diameter section and the minimum diameter section of the CVC working roll of 800mm.

[0097] The steps for establishing a comprehensive control objective function model for strip exit shape and roll wear are as follows:

[0098] Based on the initial roll profile parameters of the CVC work roll, combined with Figure 2 Calculate the initial roll profile D of the CVC work roll.g :

[0099]

[0100] Among them, D c The radius of the CVC work roll when y = ε, ΔD is the maximum roll diameter difference of the CVC work roll, s is the distance between the maximum and minimum diameter sections of the CVC work roll, ε = 0 mm is the axial displacement of the CVC work roll, and y is the corresponding number of work roll units. The initial roll profile D of the CVC work roll can be calculated from this. g =[900.18,900.165,900.15,900.135,900.12,900.105,900.09,900.075,900.06,900.045,900.03,900.015, 900,899.985,899.97,899.955,899.94,899.925,899,91,899.9,899.88,899.87,899.85,899.84,899.82]mm;

[0101] Based on the equipment characteristic parameters of the four-roll mill unit and the performance and dimensional parameters of the strip during the rolling process, the pressure distribution between the CVC work roll and the support roll, and the rolling pressure distribution between the CVC work roll and the strip are calculated under different incoming material specifications. The following details the pressure distribution between the CVC work roll and the support roll using a strip specification of [1400×21.25] mm width × thickness. 524427.63,501101.95,480562.29,462694.55,447400.17,434595.51,424211.11,416191.14,410492.75,407085.73,405952.04,407085.73,410492.75,416191.14,424211.11,434595.11,447400.17,462694.55, 480562.29,501101.95,524427.63,550669.64,579975.03,612507.94,650630.38,694478.16] Rolling pressure distribution between N and CVC work rolls and strip [595768.11,591945.96,586189.28,579141.4,571373.25,563386.07,555614.28,548428.12,5 42136.23,536987.86,533174.81,530832.95,533174.81,536987.86,542136.23,548428.12,555614.28,563386.07,571373.25,591945.96,595768.11]N, Similarly, calculate the pressure distribution between the CVC work roll and the support roll and the rolling pressure distribution between the CVC work roll and the strip for other strip specifications;

[0102] Based on the calculated pressure distribution between the CVC work roll and the support roll, the objective function N1(X) for controlling the pressure distribution between the CVC work roll and the support roll is calculated:

[0103]

[0104] Where λ = 0.5 is the pressure distribution control coefficient between the CVC work roll and the support roll, M = 31 is the total number of units equally divided by the CVC work roll, and Y c (y) represents the pressure distribution between the CVC work roll and the support roll. It is the average pressure between the CVC work roll and the support roll. N1(X) can be calculated from this. i= {0.78, 0.81, 0.74, 0.86, 0.79, 0.81, 0.85}, the objective function for controlling the pressure distribution between the CVC work roll and support roll is N1(X) = 0.806;

[0105] Based on the calculated rolling pressure distribution between the CVC work roll and the strip, the objective function N2(X) for controlling the rolling pressure distribution between the CVC work roll and the strip is calculated:

[0106]

[0107] Where γ = 0.4 is the rolling pressure distribution control coefficient between the CVC work roll and the strip, N = 25 is the total number of units that divide the strip equally, and F c (y) represents the rolling pressure distribution between the CVC work roll and the strip. It is the average rolling pressure between the CVC work roll and the strip, which can be calculated to obtain N2(X). i The objective function for controlling the rolling pressure distribution between the CVC work roll and the strip is N2(X) = 0.739, where X = {0.71, 0.66, 0.87, 0.71, 0.71, 0.77, 0.74}.

[0108] Based on the calculated objective function N1(X) for controlling the pressure distribution between the CVC work roll and the support roll, and the objective function N2(X) for controlling the rolling pressure distribution between the CVC work roll and the strip, the objective function G1(X) for controlling the roll wear of the CVC work roll is calculated:

[0109] G1(X)=κN1(X)+(1-κ)N2(X)

[0110] Where κ=0.5 is the weighting coefficient, the objective function for CVC work roll wear control is calculated to be G1(X)=0.7725;

[0111] Based on the calculated pressure distribution between the CVC work roll and the support roll, and the rolling pressure distribution between the CVC work roll and the strip, the CVC work roll deflection and the strip exit thickness are calculated. The following details the calculation using a strip specification of [1400×21.25] mm (width × thickness). The CVC work roll deflection is [0.076, 0.086, 0.0878, 0.082, 0.074, 0.065, 0.055, 0.046, 0.036, 0.027, 0.02, 0.013, 0.007, 0.003, 0.0008, 0, 0.008, 0.003, 0.007, 0.013, 0.02, 0.0]. The values ​​are 27, 0.036, 0.046, 0.055, 0.065, 0.074, 0.082, 0.088, 0.086, 0.076] and the strip exit thickness distribution is [13.96, 13.97, 13.98, 13.99, 14, 14, 14, 14.01, 14.02, 14.02, 14.02, 14.02, 14.02, 14.02, 14.02, 14.02, 14.02, 14.01, 14, 14, 14, 13.98, 13.97, 13.96] mm. Similarly, calculate the CVC work roll deflection and strip exit thickness distribution for other strip specifications.

[0112] Based on the calculated CVC work roll deflection and strip exit thickness distribution, the strip exit tension distribution and shape distribution are calculated. The following details the distribution using a strip specification of [1400×21.25] mm width × thickness. The strip exit tension distribution is [10.75, 10.89, 11.09, 11.34, 11.61, 11.88, 12.15, 12.62, 12.8, 12.93, 13.01, 13.04, 13.01, 12.93, 12.8, 12.62, 12.4, 12.15, 11.88, ... [11.61,11.34,11.09,10.89,10.75] and strip shape distribution [3.61,3.21,2.62,1.91,1.13,0.33,-0.45,-1.16,-1.79,-2.31,-2.69,-2.92,-3,-2.69,-2.31,-1.79,-1.16,-0.45,0.33,1.13,1.19,2.62,3.21,3.61] MPa. Similarly, calculate the strip tension distribution and strip shape distribution before exit for other strip specifications.

[0113] Based on the calculated strip exit shape distribution, the objective function G2(X) for strip exit shape control is established:

[0114]

[0115] Where ω=0.7 is the strip shape control coefficient at the strip exit, I y It is the strip steel export plate shape distribution, I max It is the maximum value of the strip steel export shape, I min It is the minimum strip shape at the export point, and G2(X) can be calculated. i ={2.11,2.05,2.05,1.74,1.81,1.8}8, the objective function for strip steel outlet shape control is G2(X) = 1.946;

[0116] Based on the obtained CVC work roll wear control objective function G1(X) and strip exit shape control objective function G2(X), a comprehensive control objective function G(X) for both CVC work roll wear and strip exit shape control is established:

[0117] G(X) = αG1(X) + βG2(X)

[0118] Where α=β=0.5 are weighting coefficients, the comprehensive control objective function G(X)=1.359 for the combined control of CVC work roll wear and strip exit shape can be obtained;

[0119] The Powell condition is determined to be invalid. The parameters of the maximum roll diameter difference of the CVC work roll and the distance between the maximum and minimum diameter sections of the CVC work roll are updated, and the optimization continues. Through iterative calculations, the result is obtained... The loop has ended.

[0120] Based on the optimization results, the optimal solution of the CVC working roll profile curve parameters is obtained, and the optimal values ​​of the CVC working roll profile curve parameters are output. The maximum roll diameter difference of the CVC working roll is 12mm, and the distance between the maximum diameter section and the minimum diameter section of the CVC working roll is 918mm.

[0121] As shown in Table 1, it can be seen that by optimizing the CVC work roll profile curve parameters, the optimal values ​​of the CVC work roll profile curve parameters are determined. Under the premise of ensuring unit production, the roll consumption of the work roll is reduced to the greatest extent, while improving the strip exit shape and increasing production efficiency.

[0122] Table 1 Comparison of roll consumption and plate shape effect before and after optimization of work roll profile curve in Example 1

[0123]

[0124] Example 2:

[0125] like Figure 1 The steps of this invention are as follows:

[0126] S1. Collect equipment characteristic parameters of the four-roll mill unit;

[0127] S2. Collect typical strip steel performance and dimensional parameters during the rolling process;

[0128] S3. Set the initial roll profile parameters for the CVC work roll;

[0129] S4. Establish a comprehensive control objective function model for strip steel exit shape and roll wear;

[0130] S5. Optimize the working roll profile parameters and output the optimal parameter values.

[0131] Specifically, it includes:

[0132] The main characteristic parameters of the four-roll mill unit collected include total rolling pressure, support force 810t, bending force 75t, radius of axial displacement of CVC work roll 1000mm, maximum and minimum difference in maximum roll diameter of CVC work roll 20mm and 14mm, maximum and minimum distance between maximum and minimum radius sections of CVC work roll 1400mm and 900mm, support roll diameter 1200mm, CVC work roll length 2200mm, and support roll length 1900mm.

[0133] The main performance and dimensional parameters of typical strip steel collected during the rolling process include strip width [960, 1040, 1160, 1240, 1360, 1440, 1560] mm, average incoming strip thickness [22.14, 22.85, 23.17, 23.89, 24.22, 24.91, 25.65] mm, and strip elastic modulus of 2.1 × 10⁻⁶. 5 MPa and Poisson's ratio 0.3, strip deformation resistance 107MPa;

[0134] Define the roll wear control objective function G1(X), the strip exit shape control objective function G2(X), and the combined strip exit shape and roll wear control objective function G(X);

[0135] The initial roll profile parameters of the CVC working roll are set, mainly including the optimization step size of 1mm and the initial number of optimizations of the CVC working roll roll profile optimization parameters of 0, the initial value of the maximum roll diameter difference of the CVC working roll of 8mm, the maximum roll diameter difference of the CVC working roll and the distance between the maximum diameter section and the minimum diameter section of the CVC working roll of 800mm.

[0136] The steps for establishing a comprehensive control objective function model for strip exit shape and roll wear are as follows:

[0137] Based on the initial roll profile parameters of the CVC work roll, combined with Figure 2 Calculate the initial roll profile D of the CVC work roll. g :

[0138]

[0139] Among them, D c The radius of the CVC work roll when y = ε, ΔD is the maximum roll diameter difference of the CVC work roll, s is the distance between the maximum and minimum diameter sections of the CVC work roll, ε = 0 mm is the axial displacement of the CVC work roll, and y is the corresponding number of work roll units. The initial roll profile D of the CVC work roll can be calculated from this. g =[1000.16,1000.15,1000.13,1000.12,1000.11,1000.09,1000.08,1000.07,1000.05,1000.04,1000.03,1000. 01,1000,999.99,999.97,999.96,999.95,999.93,999.92,999.91,999.89,999.88,999.87,999.85,999.84]mm;

[0140] Based on the equipment characteristic parameters of the four-roll mill unit and the performance and dimensional parameters of the strip during the rolling process, the pressure distribution between the CVC work roll and the support roll, and the rolling pressure distribution between the CVC work roll and the strip are calculated under different incoming material specifications. The following details the pressure distribution between the CVC work roll and the support roll using a strip specification of [1560×25.65] mm width × thickness: [645492.2, 604824.9, 569445.8, 539230.8, 511]. 994.8,487588.4,465878.5,446747.8,430094.2,415829.7,403880.3,394184.4,386693,381368.5,378184.2,377124.6,378184.2,381368.5,386693,394184.4,403880.3,415829.7,430094.2,446747 .8,465878.5,487588.4,511994.8,539230.8,604824.9,645492.2] Rolling pressure distribution between N and CVC work rolls and strip [555791.8,551952.1,546175.3,539111.6,531335.4,523349,515586,508414.3,502139.9,497009,493210.7, 490878.7,490092.5,490878.7,493210.7,497009,502139.9,508414.3,515586,523349,531335.4,539111.6,546175.3,551952.1,555791.8]N, Similarly, calculate the pressure distribution between the CVC work roll and the support roll and the rolling pressure distribution between the CVC work roll and the strip for other strip specifications;

[0141] Based on the calculated pressure distribution between the CVC work roll and the support roll, the objective function N1(X) for controlling the pressure distribution between the CVC work roll and the support roll is calculated:

[0142]

[0143] Where λ = 0.5 is the pressure distribution control coefficient between the CVC work roll and the support roll, M = 31 is the total number of units equally divided by the CVC work roll, and Y c (y) represents the pressure distribution between the CVC work roll and the support roll. It is the average pressure between the CVC work roll and the support roll. N1(X) can be calculated from this. i={0.82,0.85,0.79,0.83,0.76,0.79,0.79}, the objective function for controlling the pressure distribution between the CVC work roll and the support roll is N1(X) = 0.804;

[0144] Based on the calculated rolling pressure distribution between the CVC work roll and the strip, the objective function N2(X) for controlling the rolling pressure distribution between the CVC work roll and the strip is calculated:

[0145]

[0146] Where γ = 0.4 is the rolling pressure distribution control coefficient between the CVC work roll and the strip, N = 25 is the total number of units that divide the strip equally, and F c (y) represents the rolling pressure distribution between the CVC work roll and the strip. It is the average rolling pressure between the CVC work roll and the strip, which can be calculated to obtain N2(X). i ={0.83,0.75,0.81,0.72,0.74,0.75,0}.7, the objective function for controlling the rolling pressure distribution between the CVC work roll and the strip is N2(X) = 0.767;

[0147] Based on the calculated objective function N1(X) for controlling the pressure distribution between the CVC work roll and the support roll, and the objective function N2(X) for controlling the rolling pressure distribution between the CVC work roll and the strip, the objective function G1(X) for controlling the roll wear of the CVC work roll is calculated:

[0148] G1(X)=κN1(X)+(1-κ)N2(X)

[0149] Where κ=0.5 is the weighting coefficient, the objective function for CVC work roll wear control is calculated to be G1(X)=0.78;

[0150] Based on the calculated pressure distribution between the CVC work roll and the support roll, and the rolling pressure distribution between the CVC work roll and the strip, the CVC work roll deflection and the strip exit thickness are calculated. The following details the calculation using a strip specification of [1560×25.65] mm (width × thickness). The CVC work roll deflection is [0.065, 0.075, 0.077, 0.072, 0.065, 0.057, 0.049, 0.04, 0.032, 0.024, 0.017, 0.011, 0.006, 0.003, 0.001, 0, 0.001, 0.003, 0.006, 0.011, 0.01]. The values ​​are 7, 0.024, 0.032, 0.04, 0.049, 0.057, 0.065, 0.072, 0.077, 0.075, 0.065] and the strip exit thickness distribution [13.97, 13.98, 13.98, 13.99, 14, 14, 14, 14, 14.01, 14.02, 14.02, 14.02, 14.02, 14.02, 14.02, 14.02, 14.01, 14, 14, 14, 13.99, 13.98, 13.97] mm. Similarly, the CVC work roll deflection and strip exit thickness distribution are calculated for other strip specifications.

[0151] Based on the calculated CVC work roll deflection and strip exit thickness distribution, the strip exit tension distribution and strip shape distribution are calculated. The following details the distribution using a strip specification of [1560×25.65] mm width × thickness. The strip exit tension distribution is [12.05, 12.15, 12.31, 12.49, 12.7, 12.91, 13.12, 13.31, 13.47, 13.61, 13.71, 13.77, 13.79, 13.77, 13.71, 13.61, 13.47, 13.31, 13.12, .12]. The strip tension distribution and strip shape distribution are calculated as follows: [91, 12.7, 12.49, 12.31, 12.15, 12.05] MPa and [2.75, 2.45, 2, 1.46, 0.86, 0.25, -0.34, -0.89, -1.37, -1.76, -2.05, -2.23, -2.29, -2.23, -2.05, -1.76, -1.37, -0.89, -0.34, 0.25, 0.86, 1.46, 2, 2.45, 2.75]. Similarly, the tension distribution and strip shape distribution before exiting the strip are calculated for other strip specifications.

[0152] Based on the calculated strip exit shape distribution, the objective function G2(X) for strip exit shape control is established:

[0153]

[0154] Where ω=0.7 is the strip shape control coefficient at the strip exit, I y It is the strip steel export plate shape distribution, I max It is the maximum value of the strip steel export shape, I min It is the minimum strip shape at the export point, and G2(X) can be calculated. i ={1.98,1.87,1.85,1.21,1.28,1.45,1}.5, the objective function for strip steel export shape control is G2(X) = 1.6;

[0155] Based on the obtained CVC work roll wear control objective function G1(X) and strip exit shape control objective function G2(X), a comprehensive control objective function G(X) for both CVC work roll wear and strip exit shape control is established:

[0156] G(X) = αG1(X) + βG2(X)

[0157] Where α=β=0.5 are weighting coefficients, the comprehensive control objective function G(X)=1.19 for the combined control of CVC work roll wear and strip exit shape can be obtained;

[0158] The Powell condition is determined to be invalid. The parameters of the maximum roll diameter difference of the CVC work roll and the distance between the maximum and minimum diameter sections of the CVC work roll are updated, and the optimization continues. Through iterative calculations, the result is obtained... The loop has ended.

[0159] Based on the optimization results, the optimal solution of the CVC working roll profile curve parameters is obtained, and the optimal values ​​of the CVC working roll profile curve parameters are output. The maximum roll diameter difference of the CVC working roll is 17mm, and the distance between the maximum diameter section and the minimum diameter section of the CVC working roll is 1024mm.

[0160] As shown in Table 2, it can be seen that by optimizing the CVC work roll profile curve parameters, the optimal values ​​of the CVC work roll profile curve parameters are determined. Under the premise of ensuring unit production, the roll consumption of the work roll is reduced to the greatest extent, while improving the strip exit shape and increasing production efficiency.

[0161] Table 2 Comparison of roll consumption and plate shape effect before and after optimization of work roll profile curve in Example 2

[0162]

Claims

1. A method for controlling roll wear, characterized in that... Includes the following steps: S1. Collect equipment characteristic parameters of the four-roll mill unit; S2. Collect the performance and dimensional parameters of typical strip steel during the rolling process; S3. Set the initial roll profile parameters for the CVC work roll; S4. Establish a comprehensive control objective function model for strip steel exit shape and roll wear; S5. Optimize the working roll profile parameters and output the optimal parameter values; The specific steps in step S4 include: S4.1 Calculate the initial roll profile D of the CVC work roll. g : Among them, D c y is the radius of the CVC working roll when y = ε, ΔD is the maximum diameter difference of the CVC working roll, s is the distance between the maximum diameter section and the minimum diameter section of the CVC working roll, ε is the axial displacement of the CVC working roll, and y is the corresponding number of working roll units; S4.2 Calculate the pressure distribution between the CVC work roll and the support roll and the rolling pressure distribution between the CVC work roll and the strip steel under different incoming material specifications; S4.3 Establish the objective function for CVC work roll wear control: Based on the calculated pressure distribution between the CVC work roll and support roll under different incoming material specifications, the objective function N1(X) for controlling the pressure distribution between the CVC work roll and support roll under different incoming material specifications is calculated. Among them, N1(X) i ) is the objective function for controlling the pressure distribution between the CVC work roll and support roll corresponding to the i-th strip specification, n is the total number of typical strip specifications, λ is the control coefficient for the pressure distribution between the CVC work roll and support roll, M is the total number of units bisected by the CVC work roll, and Y c (y) represents the pressure distribution between the CVC work roll and the support roll. It is the average pressure between the CVC work roll and the support roll; Based on the calculated rolling pressure distribution between the CVC work roll and the strip, the objective function N2(X) for controlling the rolling pressure distribution between the CVC work roll and the strip under different incoming material specifications is calculated: Among them, N2(X) i ) is the objective function for controlling the rolling pressure distribution between the CVC work roll and the strip for the i-th type of strip, γ is the control coefficient for the rolling pressure distribution between the CVC work roll and the strip, N is the total number of units bisected by the strip, and F c (y) represents the rolling pressure distribution between the CVC work roll and the strip. It is the average rolling pressure between the CVC work roll and the strip; Based on the calculated objective function N1(X) for controlling the pressure distribution between the CVC work roll and the support roll, and the objective function N2(X) for controlling the rolling pressure distribution between the CVC work roll and the strip, the objective function G1(X) for controlling the roll wear of the CVC work roll is calculated: G1(X)=κN1(X)+(1-κ)N2(X) Where κ is the weighting coefficient; S4.4 Calculate the CVC work roll deflection and strip exit thickness distribution; S4.5 Calculate the tension distribution and strip shape distribution before the strip exits; S4.6 Establish the objective function for controlling the strip shape at the exit: Among them, G2(X) i ) is the objective function for controlling the strip shape at the i-th exit, ω is the strip shape control coefficient at the exit, and I y It is the strip steel export plate shape distribution, I max It is the maximum value of the strip steel export shape, I min It is the minimum value of the strip steel export shape; S4.7 Establish a comprehensive control objective function that combines control of CVC work roll wear and strip exit shape. G(X) = αG1(X) + βG2(X) Where α and β are weighting coefficients; In step S5, the roll profile parameters of the work roll are optimized, and the optimal parameter values ​​are output. Specific steps include: Determine whether the Powell condition holds, i.e., calculate a certain objective function G. j (X) and the next objective function G j+1 Does (X) exist? If the condition is met, the optimization ends; otherwise, update the parameters of the maximum roll diameter difference of the CVC working roll and the distance between the maximum and minimum diameter sections of the CVC working roll, and continue the optimization. Based on the optimization results, the optimal solution of the CVC work roll profile curve parameters is obtained, and the optimal value of the CVC work roll profile curve parameters is output. The updated parameters for the maximum roll diameter difference of the CVC work roll and the distance between the maximum and minimum diameter sections of the CVC work roll are as follows: Where, ΔD min It is the minimum difference between the maximum and minimum diameters of the CVC work rolls, ΔD max It is the maximum difference in diameter between the CVC work rolls, s min It is the minimum distance between the maximum and minimum diameter sections of the CVC work roll, s max V(ΔD,s) is the maximum distance between the maximum and minimum diameter sections of the CVC work roll, and V(ΔD,s) is the combination of the maximum roll diameter difference of the CVC work roll and the distance between the maximum and minimum diameter sections of the CVC work roll. min (ΔD,s) is the minimum value of the optimization variables for the maximum roll diameter difference of the CVC working roll and the distance between the maximum and minimum diameter sections of the CVC working roll, k is the number of optimizations, and Δν(ΔD,s) is the optimization step size for the optimization variables for the maximum roll diameter difference of the CVC working roll and the distance between the maximum and minimum diameter sections of the CVC working roll.

2. The method for controlling roll wear according to claim 1, characterized in that: In step S1, the equipment characteristic parameters of the four-roll mill unit are collected, including total rolling pressure, support force, bending force, diameter of CVC work roll at axial displacement, maximum and minimum values ​​of the maximum diameter difference of CVC work roll, maximum and minimum values ​​of the distance between the maximum and minimum radius sections of CVC work roll, support roll diameter, CVC work roll length, and support roll length.

3. The method for controlling roll wear according to claim 1, characterized in that: In step S2, typical strip steel performance and dimensional parameters during the rolling process are collected, including strip steel width, strip steel thickness, strip steel elastic modulus and Poisson's ratio, and strip steel deformation resistance.

4. The method for controlling roll wear according to claim 1, characterized in that: In step S3, the initial roll profile parameters of the CVC working roll are set, including the CVC working roll profile optimization parameters, as well as the optimization step size and initial number of optimizations for the CVC working roll profile optimization parameters; the CVC working roll profile optimization parameters include the maximum roll diameter difference of the CVC working roll and the distance between the maximum diameter section and the minimum diameter section of the CVC working roll.

Images