X-type six-roller mill plate shape rapid forecasting method based on model coupling method

Abstract

The invention provides an X-type six-high mill plate shape rapid forecasting method based on a model coupling method, and belongs to the technical field of metallurgical rolling. The method comprises the following steps: collecting equipment parameters of the X-type six-roller mill, strip characteristic parameters and corresponding rolling process parameters; dividing units and solving influence coefficients; forecasting the transverse distribution value of the pre-tensile stress of the strip during rolling; and strip outlet plate shape transverse distribution during rolling is forecasted. According to the method, the strip plastic deformation model and the roll system elastic deformation model are integrated into a unified linear equation set based on the model coupling method, and iterative calculation between the strip plastic deformation model and the roll system elastic deformation model can be avoided. Two calculation examples show that the calculation result of the X-type six-high rolling mill plate shape rapid forecasting method based on the model coupling method is well matched with that of a traditional method, and the calculation speed is increased by about 500 times.

Description

Technical Field

[0001] The invention relates to the technical field of metallurgical rolling, and in particular to a method for quickly predicting the plate shape of an X-type six-high rolling mill based on a model coupling method. Background Art

[0002] With the continuous development of the automotive, aerospace and other industries, the quality requirements for copper strips are also increasing, and the demand for thin strip products is particularly prominent. The traditional four- and six-roll rolling mills have a large working diameter and poor thinning ability due to the limitation of the minimum rollable thickness. [1] In addition, the rigidity of the traditional rolling mill may not meet the requirements when the copper strip is cold rolled. Although the twenty-high rolling mill meets the requirements for producing high-quality copper strip in terms of rolling capacity and rigidity, it has a complex rolling mill structure. [2] The X-type six-roller mill has the disadvantages of simple structure, low cost, high production efficiency, and the rigidity and thinning capacity of the mill can better meet the requirements of producing copper thin strips. [3-4] . In the actual production process of the X-type six-roll mill, the flatness problem is more obvious due to the thinness of the rolled strip. It is necessary to establish a mathematical model to quantitatively analyze the flatness problem and adjust the parameters to effectively control the flatness. By analyzing the mechanism of the rolling mill and establishing a flatness prediction model, the flatness can be predicted and feedback controlled. The traditional flatness prediction model iterates the strip plastic deformation model and the roller system elastic deformation model until convergence. The model has a large amount of calculation and poor convergence. [5] Domestic and foreign research on flatness prediction models mainly focuses on how to model the two sub-models and how to deal with the coupling relationship between the two.

[0003] References:

[0004] [1] Wang Dongcheng, Ren Yinjie, Lü Youchuang, et al. Rapid prediction model of flatness of Sendzimir 20-roll mill [J / OL]. Steel, 1-16.

[0005] [2] Zhang Qingdong, Dai Chang, Wen Jie, et al. Simulation study on the plate shape control performance of 20-high Sendzimir mill [J]. Steel Rolling, 2013, 30(03): 1-6.

[0006] [3] Chen Chuncan. Research on key technologies and equipment development of X-type 6-roll copper foil rolling mill[J]. Nonferrous Metal Processing, 2018, 47(01): 1-4+16.

[0007] [4]Cao Wenjuan. Research and development of copper foil working roll of X-type six-roll mill[J]. Heat Treatment, 2020, 35(06): 32-36.

[0008] [5] Wang Dongcheng, Zhang Wei, Wang Zhijie, et al. Rapid prediction method of strip shape of six-roll cold rolling mill [J]. Steel, 2016, 51(09): 51-56. Summary of the invention

[0009] According to the above technical problem that the X-type six-roll mill has poor plate shape (straightness) during the production process, a method for rapid prediction of plate shape of an X-type six-roll mill based on a model coupling method is provided. The present invention is a method for rapid prediction of plate shape of an X-type six-roll mill based on a model coupling method. The present invention integrates the strip plastic deformation model and the roller system elastic deformation model into a unified linear equation group based on the model coupling method, which can avoid iterative calculation between the two.

[0010] The technical means adopted by the present invention are as follows:

[0011] A method for rapid prediction of plate shape of an X-type six-high rolling mill based on a model coupling method comprises the following steps:

[0012] Step 1: Obtain the basic equipment parameters of the X-type six-high rolling mill and the rolling process parameters of the strip;

[0013] Step 2: Divide the roller and the strip into units, a total of t units; the coordinate of the center point of each unit width is y i , i=1,2,…,t, each unit width is Δy i , i=1,2,…,t;

[0014] Step 3: Solve the support roller deflection influence coefficient α bij , working roll deflection influence coefficient matrix α wij And the working roll bending influence coefficient α Fwi ;

[0015] Step 4: Preset the initial value h of strip exit thickness distribution 1i ;

[0016] Step 5: Preset the initial value of the pressure distribution between the rollers to q i ;

[0017] Step 6: Calculate the strip plastic deformation by the strip element variation method in the three-dimensional plastic deformation model, and perform a simple deformation on the lateral displacement equation group at the node line outlet;

[0018] Step 7: Solve the roller flattening influence coefficient;

[0019] Step 8: List the deformation coordination equation between the rolls of the roll system;

[0020] Step 9: List the force and moment balance equations of the support roll and the working roll;

[0021] Step 10: From the perspective of elastic deformation of the roller system, obtain expression 1 of the strip outlet thickness distribution;

[0022] Step 11: From the perspective of strip plastic deformation, obtain expression 2 of strip outlet thickness distribution;

[0023] Step 12: Combine the expression 1 of the strip outlet thickness distribution in step 10 with the expression 2 of the strip outlet thickness distribution in step 11;

[0024] Step 13: According to the average thickness of the strip outlet is equal to Performing discrete integration on Expression 1 of the strip outlet thickness distribution;

[0025] Step 14: After discrete integration of the expression 1 of the strip outlet thickness distribution, substitute the equation on the right side of the equal sign in step 12;

[0026] Step 15: After the equations in steps 6, 7, 8, 9, 12, and 14 are combined, the number of unknowns is consistent with the number of equations, and all unknowns in the linear equation system are solved; since the coefficient matrix of the linear equation system contains the elastic flattening coefficient between rollers, and the elastic flattening coefficient between rollers is related to the pressure between rollers, it is necessary to iteratively calculate the pressure between rollers;

[0027] Step 16: Determine whether the calculated value q′ satisfies the inequality max|q′-q|<0.01; if not, set q=q+0.1(q′-q) and proceed to step 6; if yes, proceed to step 17;

[0028] Step 17: Output the transverse distribution value σ of the strip pre-tension stress 1i ;

[0029] Step 18: According to the transverse distribution value σ of the strip pre-tension stress 1i , calculate the strip shape distribution BX at the current moment i ;

[0030]

[0031] Furthermore, in step 1, the basic equipment parameters of the X-type six-high rolling mill include: the roll length, roll radius, crown, elastic modulus and Poisson's ratio of the support roll and the working roll, which are respectively denoted as L b , L w , R b , R w , ΔD b , ΔD w 、E b 、E w ,υ b and w , the distance between the two sides of the support point is Ls , the distance between the two bending roll hydraulic cylinders of the working roll is L Fw The angle between the line connecting the center points of the cross sections of the support roll and the working roll and the vertical direction is α.

[0032] Furthermore, in step 1, the rolling process parameters of the strip include the average thickness of the strip material. Average thickness of strip after rolling Width B, strip elastic modulus E s , Strip Poisson's ratio v s , strip deformation resistance σ s , strip shear deformation resistance k s , average post-tensioning stress of the strip Average pre-tension stress of strip Working roll bending force F w , calculate the allowable error ε and the relaxation factor χ.

[0033] Furthermore, in step 2, the coordinate origin is selected at the left pressure support of the support roller. The roller and the strip are divided into units, a total of t units; the coordinate of the center point of the width of each unit is y i , i=1,2,…,t, each unit width is Δy i , i=1,2,…,t; where the starting unit number of the contact part between the backup roll and the working roll is t1, and the ending unit number is t2; the starting unit number of the contact part between the working roll and the strip is t3, and the ending unit number is t4;

[0034] When calculating the plastic deformation of the strip, the outlet lateral displacement of the strip unit node line needs to be taken as an unknown quantity; therefore, the strip unit node lines are renumbered; the two node lines corresponding to unit t3 are numbered 0 and 1, and the two node lines corresponding to unit t4 are numbered n-1 and n, n=t4-t3+1, and the node line numbers of other units can be obtained by analogy.

[0035] Furthermore, in step 6, the expression after simple transformation is:

[0036]

[0037] Among them, u0, u1, ...u n They represent the lateral displacement of the strip unit node line outlet, which is an unknown quantity; They represent the lateral distribution of rolling pressure, which is an unknown quantity; ψ is related to unit width, strip elastic modulus, strip Poisson's ratio, strip shear deformation resistance, neutral point thickness, work roll elastic flattening radius, friction coefficient, average friction stress of contact surface in deformation zone, thickness before rolling, reduction, deformation zone length, and stress state coefficient; represents the equivalent deformation resistance,

[0038] Furthermore, in step 7, the elastic flattening influence coefficient γ between the rollers is i , the equation of the roller flattening amount and roller pressure distribution is:

[0039] δ i =γ i q i ,(i=t1~t2);

[0040] Among them, δ i Indicates the elastic flattening amount between rollers; q i Represents the roller pressure of the i-th unit.

[0041] Furthermore, in step 8, the inter-roller deformation coordination equation is:

[0042] f wi =2cosα(f bi +δ i +ΔD i ),(i=t1~t2);

[0043] Among them, f w Indicates the deflection of the working roll in the vertical direction; f b It indicates the deflection of the support roll along the line connecting the center points of the support roll and the working roll. ΔD indicates the no-load gap between the rolls, i.e., the crown. ΔD i =(ΔD wi +ΔD bi ) / 2.

[0044] Furthermore, in step 9, the force and moment balance equation of the working roll is:

[0045]

[0046] Among them, p i Represents the rolling pressure of the i-th unit.

[0047] Furthermore, in step 10, the expression 1 for obtaining the strip outlet thickness distribution is:

[0048] h 1i =s0+2f wi +2δ wi +ΔD i ,(i=t3~t4);

[0049] Among them, δ wi Indicates the amount of elastic flattening of the working roll surface in contact with the workpiece.

[0050] Furthermore, in step 11, expression 2 for obtaining the strip outlet thickness distribution is:

[0051]

[0052] in, Respectively represent the average thickness of the strip at the entrance and exit, F i It represents constants related to unit width, strip elastic modulus, strip Poisson's ratio, neutral point thickness, average friction stress of contact surface in deformation zone, reduction, strip shear deformation resistance, and deformation zone length. Compared with the prior art, the present invention has the following advantages:

[0053] The invention takes the pressure distribution between the rolls of the X-type six-roll mill, the rolling force distribution, the strip outlet lateral displacement distribution, the rigid displacement and the no-load roll gap as the basic unknowns, and integrates the strip plastic deformation model and the roll system elastic deformation model into a unified linear equation set based on the model coupling method, which can avoid iterative calculation between the two. Two calculation examples show that the X-type six-roll mill plate shape rapid prediction method based on the model coupling method. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0055] Figure 1 It is the overall calculation flow chart of the present invention;

[0056] Figure 2 It is a schematic diagram of the segmented roller system of the X-type six-roller rolling mill of the present invention;

[0057] Figure 3 It is a distribution angle and number diagram of the roll system of the X-type six-roller rolling mill of the present invention;

[0058] Figure 4 It is a corresponding relationship diagram between the unit node line number and the unit number of the present invention;

[0059] Figure 5 It is the lateral distribution diagram of the plate shape of Examples 1 and 2 of the present invention. DETAILED DESCRIPTION

[0060] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0061] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0062] like Figure 1 As shown, the present invention provides a method for rapid prediction of plate shape of an X-type six-high rolling mill based on a model coupling method, comprising the following steps:

[0063] Step 1: Obtain the basic equipment parameters of the X-type six-high mill, including: the roll length, roll radius, crown, elastic modulus and Poisson's ratio of the support roll and the working roll, respectively denoted as L b , L w , R b , R w , ΔD b , ΔD w 、E b 、E w ,υ b and w , the distance between the two sides of the support point is L s , the distance between the two bending roll hydraulic cylinders of the working roll is L Fw The angle between the line connecting the center points of the cross sections of the support roll and the working roll and the vertical direction is α.

[0064] At the same time, the rolling process parameters of the strip are obtained, including: the average thickness of the incoming strip Average thickness of strip after rolling Width B, strip elastic modulus E s , Strip Poisson's ratio υ s , strip deformation resistance σ s , strip shear deformation resistance k s, average post-tensioning stress of the strip Average pre-tension stress of strip Working roll bending force F w , calculate the allowable error ε and the relaxation factor X.

[0065] Step 2: Unit division, such as Figure 2 As shown. The origin of the coordinates is selected at the left support point of the support roller. The roller and the strip are divided into units, a total of t units. The coordinate of the center point of each unit width is y i (i=1,2,…,t), each unit width is Δy i (i=1,2,…,t). Among them, the starting unit number of the contact part between the support roll and the working roll is t1, and the ending unit number is t2; the starting unit number of the contact part between the working roll and the strip is t3, and the ending unit number is t4. When calculating the plastic deformation of the strip, the exit lateral displacement of the strip unit node line needs to be taken as an unknown quantity. Therefore, the strip unit node lines are renumbered, such as Figure 4 As shown. The two node lines corresponding to unit t3 are numbered 0 and 1, and the two node lines corresponding to unit t4 are numbered n-1 and n, (n=t4-t3+1). The node line numbers of other units can be obtained by analogy;

[0066] Step 3: Solve the deflection influence coefficient of each roll and the bending influence coefficient of the working roll, including: Calculate the deflection influence coefficient α of the working roll wij , Working roll bending influence coefficient α Fwi and the support roller deflection influence coefficient α bij ;

[0067] Step 4: Given the initial value h of the strip exit thickness distribution 1i ;

[0068] Step 5: Given the initial value of the pressure distribution between the rollers as q i Among them, q i It represents the contact pressure between the backup roll and the working roll on the i unit;

[0069] Step 6: Use the strip element variation method in the three-dimensional plastic deformation model to calculate the strip plastic deformation and perform a simple deformation on the node line outlet lateral displacement equation group:

[0070]

[0071] Among them, u0, u1, ...u n They represent the lateral displacement of the strip unit node line outlet, which is an unknown quantity; They represent the lateral distribution of rolling pressure, which is an unknown quantity; ψ is related to unit width, strip elastic modulus, strip Poisson's ratio, strip shear deformation resistance, neutral point thickness, work roll elastic flattening radius, friction coefficient, average friction stress of contact surface in deformation zone, thickness before rolling, reduction, deformation zone length, and stress state coefficient; represents the equivalent deformation resistance,

[0072] Step 7: Solve for the roller flattening influence coefficient γ i , the equation of the roller flattening amount and roller pressure distribution is:

[0073] δ i =γ i q i ,(i=t1~t2);

[0074] Among them, δ i Indicates the amount of elastic flattening between rollers;

[0075] Step 8: By analyzing the geometric deformation of the roll system of the X-type six-high rolling mill, the deformation coordination equation between the rolls can be listed:

[0076] f wi =2cosα(f bi +δ i +ΔD i ),(i=t1~t2);

[0077] Among them, f w Indicates the deflection of the working roll in the vertical direction; f b It indicates the deflection of the support roll along the line connecting the center points of the support roll and the working roll. ΔD indicates the no-load gap (convexity) between the rolls. ΔD i =(ΔD wi +ΔD bi ) / 2;

[0078] Step 9: According to the force and moment balance, the force and moment balance equation of the working roll can be listed as follows:

[0079]

[0080] Step 10: From the perspective of elastic deformation of the roller system, the expression for the strip outlet thickness distribution is as follows:

[0081] h 1i =s0+2f wi +2δ wi +ΔD i ,(i=t3~t4);

[0082] Where: s0 is the no-load roll gap value, ΔD i is the working roll profile distribution value, δ wiIndicates the elastic flattening amount of the working roll surface in contact with the rolled product. β ij is the elastic flattening influence coefficient of the strip on the working roll;

[0083] Step 11: From the perspective of strip plastic deformation, the expression for strip outlet thickness distribution is as follows:

[0084]

[0085] in, Respectively represent the average thickness of the strip at the entrance and exit, F i Indicates that there are constants with unit width, strip elastic modulus, strip Poisson's ratio, neutral point thickness, average friction stress of contact surface in deformation zone, reduction, strip shear deformation resistance, and deformation zone length;

[0086] Step 12: Combine step 10 with step 11 to get:

[0087]

[0088] Among them, C1 and C2 are respectively the vertical rigid displacements of the left and right end axes of the working roll body;

[0089] Step 13: According to the average thickness of the strip outlet is equal to This condition, the left and right sides of the equation in step 10 are discretely integrated, and the integral on the left side of the equation is:

[0090]

[0091] Step 14: After integrating the right side of the equation in step 10, substitute the equation in step 13 to obtain:

[0092]

[0093] Step 15: After combining the equations in steps 6, 7, 9, 12, and 14, the number of unknowns is the same as the number of equations, so they can be solved directly. In addition, since the coefficient matrix of the linear equation system contains the elastic flattening coefficient between the rollers, and the elastic flattening coefficient between the rollers is related to the pressure between the rollers, it is necessary to iteratively calculate the pressure between the rollers;

[0094] Step 16: Determine whether the inequality max|q′-q|<0.01 holds. If not, let q=q+0.1(q′-q) and go to step 6. If it holds, go to step 17.

[0095] Step 17: Output the transverse distribution value σ of the strip front tensile stress during rolling by the X-type six-high rolling mill 1i ;

[0096] Step 18: According to the transverse distribution value σ of the strip pre-tension stress 1i , calculate the strip shape distribution BX when the X-type six-high rolling mill is rolling i :

[0097]

[0098] Example 1

[0099] Taking a certain X-type six-roller rolling mill as an example, according to Figure 1 The overall calculation flow chart of the X-type six-high mill plate shape rapid prediction method based on the model coupling method is shown in the figure. First, in step 1, the basic equipment parameters of the X-type six-high mill are collected: the radius R of the working roll body w =62.5mm, support roller radius R b =300mm, working roll elastic modulus E w =236GPa, elastic modulus of support roller E b =236GPa, Poisson's ratio of working roll w =0.3, Poisson's ratio of support roller b =0.3, the distance between the left and right pressing support points is L s =1000mm, working roll body length L w =800mm, distance between two bending roller hydraulic cylinders of working roller l Fw =1000mm, support roller body length l b =800mm, the angle between the line connecting the center points of the working roll and the support roll and the vertical direction is α=50°, and the crown of the working roll is ΔD w =0mm, the convexity of the support roller is ΔD b =0mm.

[0100] At the same time, in step 1, the rolling process parameters of typical specifications of products are collected, mainly including the average thickness of the incoming strip Average thickness of strip after rolling Width B = 600 mm, strip elastic modulus E s =194GPa, strip Poisson's ratio υ s =0.3, strip deformation resistance σ s =300MPa, strip shear deformation resistance k s =173.1MPa, average post-tension stress of strip Average pre-tension stress of strip Working roll bending force F w =0KN, calculation tolerance ε=0.01, relaxation factor χ=0.1;

[0102] Then, in step 2, unit division is performed, and the strip and roll system unit division is as follows Figure 2As shown. The origin of the coordinates is selected at the left support point of the support roller. The roller and the strip are divided into units, a total of 100 units. The coordinate of the center point of each unit width is y i (i=1,2,…,100), each unit width is Δy i (i=1,2,…,100). The starting unit number of the contact part between the support roll and the working roll is 11, and the ending unit number is 90; the starting unit number of the contact part between the working roll and the strip is 21, and the ending unit number is 80. When calculating the plastic deformation of the strip, the exit lateral displacement of the strip unit node line needs to be taken as an unknown quantity. Therefore, the strip unit node lines are renumbered, such as Figure 3 The two node lines corresponding to unit 21 are numbered 0 and 1, the two node lines corresponding to unit 80 are numbered 59 and 60, and the node line numbers of other units can be deduced by analogy;

[0103] Then, in step 3, the deflection influence coefficient of each roll and the bending influence coefficient of the working roll are solved, including: calculating the deflection influence coefficient α of the working roll wij , Working roll bending influence coefficient α Fwi and the support roller deflection influence coefficient α bij ;

[0104] Then, in step 4, the initial value h of the strip exit thickness distribution is given 1i ;

[0105] Then, in step 5, the initial value of the pressure distribution between the rollers is given as q i ;

[0106] Then, in step 6, the strip plastic deformation is calculated using the strip element variation method in the three-dimensional plastic deformation model, and a simple deformation is performed on it:

[0107]

[0108] Then, in step 7, the inter-roller flattening influence coefficient γ is calculated i , the equation of the roller flattening amount and roller pressure distribution is:

[0109] δ i =γ i q i ,(i=11~90);

[0110] Then, in step 8, the roll-to-roll deformation coordination equation is listed:

[0111] f wi =2cosα(f bi +δ i +ΔD i ),(i=11~90);

[0112] Then, in step 9, according to the force and moment balance, the force and moment balance equation of the working roll can be listed as follows:

[0113]

[0114] Then, in step 10, from the perspective of the elastic deformation of the roller system, the expression of the strip outlet thickness distribution is as follows:

[0115] h 1i =s0+2f wi +2δ wi +ΔD i ,(i=21~80);

[0116] Subsequently, in step 11, from the perspective of strip plastic deformation, the expression for strip outlet thickness distribution is as follows:

[0117]

[0118] Then, in step 12, step 10 is combined with step 11 to obtain:

[0119]

[0120] Then, in step 13, according to the strip outlet average thickness equal to This condition, the left and right sides of the equation in step 10 are discretely integrated, and the integral on the left side of the equation is:

[0121]

[0122] Then, in step 14, after integrating the right side of the equation in step 10, substitute the equation in step 13 to obtain:

[0123]

[0124]

[0125] Then, in step 15, after combining steps 6, 7, 9, 12, and 14, the number of unknowns is consistent with the number of equations, so the solution can be directly obtained. In addition, since the coefficient matrix of the linear equation system contains the elastic flattening coefficient between rollers, and the elastic flattening coefficient between rollers is related to the pressure between rollers, it is necessary to iteratively calculate the pressure between rollers;

[0126] Then, in step 16, determine whether the inequality max|q′-q|<0.01 holds. The inequality 813.712<0.01 obviously does not hold, q=q+0.1(q′-q), go to step 6, loop until the inequality 0.0097<0.01, then go to step 17;

[0127] Then, in step 17, the transverse distribution value σ of the strip front tensile stress obtained during rolling by the X-type six-high rolling mill is output. 1i ;

[0128] Finally, in step 18, according to the transverse distribution value σ of the strip pre-tension stress 1i , calculate the strip shape distribution BX when the X-type six-high rolling mill is rolling i ,See Figure 5 (a).

[0129] Example 2

[0130] Taking a certain X-type six-roller rolling mill as an example, according to Figure 1 The overall calculation flow chart of the X-type six-high mill plate shape rapid prediction method based on the model coupling method is shown in the figure. First, in step 1, the basic equipment parameters of the X-type six-high mill are collected: the radius R of the working roll body w =62.5mm, support roller radius R b =300mm, working roll elastic modulus E w =236GPa, elastic modulus of support roller E b =236GPa, Poisson's ratio of working roll w =0.3, Poisson's ratio of support roller b =0.3, the distance between the left and right pressing support points is L s =1000mm, working roll body length L w =800mm, distance between two bending roll hydraulic cylinders of working roll L Fw =1000mm, support roller body length L b =800mm, the angle between the line connecting the center points of the working roll and the support roll and the vertical direction is α=50°, and the crown of the working roll is ΔD w =0mm, the convexity of the support roller is ΔD b =0mm.

[0131] At the same time, in step 1, the rolling process parameters of typical specifications of products are collected, mainly including the average thickness of the incoming strip Average thickness of strip after rolling Width b = 600 mm, strip elastic modulus E s =194GPa, strip Poisson's ratio υ s =0.3, strip deformation resistance σ s =300MPa, strip shear deformation resistance k s =173.1MPa, average post-tension stress of strip Average pre-tension stress of strip Working roll bending force F w =0KN, calculation tolerance ε=0.01, relaxation factor χ=0.1;

[0133] Then, in step 2, unit division is performed, and the strip and roll system unit division is as follows Figure 2 As shown. The origin of the coordinates is selected at the left support point of the support roller. The roller and the strip are divided into units, a total of 100 units. The coordinate of the center point of each unit width is y i (i=1,2,…,100), each unit width is Δy i (i=1,2,…,100). The starting unit number of the contact part between the support roll and the working roll is 11, and the ending unit number is 90; the starting unit number of the contact part between the working roll and the strip is 21, and the ending unit number is 80. When calculating the plastic deformation of the strip, the exit lateral displacement of the strip unit node line needs to be taken as an unknown quantity. Therefore, the strip unit node lines are renumbered, such as Figure 3 The two node lines corresponding to unit 21 are numbered 0 and 1, the two node lines corresponding to unit 80 are numbered 59 and 60, and the node line numbers of other units can be deduced by analogy;

[0134] Then, in step 3, the deflection influence coefficient of each roll and the bending influence coefficient of the working roll are solved, including: calculating the deflection influence coefficient α of the working roll wij , Working roll bending influence coefficient α Fwi and the support roller deflection influence coefficient α bij ;

[0135] Then, in step 4, the initial value h of the strip exit thickness distribution is given 1i ;

[0136] Then, in step 5, the initial value of the pressure distribution between the rollers is given as q i ;

[0137] Then, in step 6, the strip plastic deformation is calculated using the strip element variation method in the three-dimensional plastic deformation model, and a simple deformation is performed on it:

[0138]

[0139] Then, in step 7, the inter-roller flattening influence coefficient γ is calculated i , the equation of the roller flattening amount and roller pressure distribution is:

[0140] δ i =γ i q i ,(i=11~90);

[0141] Then, in step 8, the roll-to-roll deformation coordination equation is listed:

[0142] f wi =2cosα(f bi +δ i+ΔD i ),(i=11~90);

[0143] Then, in step 9, according to the force and moment balance, the force and moment balance equation of the working roll can be listed as follows:

[0144]

[0145] Then, in step 10, from the perspective of the elastic deformation of the roller system, the expression of the strip outlet thickness distribution is as follows:

[0146] h 1i =d0+2f wi +2δ wi +ΔD i ,(i=21~80);

[0147] Subsequently, in step 11, from the perspective of strip plastic deformation, the expression for strip outlet thickness distribution is as follows:

[0148]

[0149] Then, in step 12, step 10 is combined with step 11 to obtain:

[0150]

[0151] Then, in step 13, according to the strip outlet average thickness equal to This condition, the left and right sides of the equation in step 10 are discretely integrated, and the integral on the left side of the equation is:

[0152]

[0153] Then, in step 14, after integrating the right side of the equation in step 10, substitute the equation in step 13 to obtain:

[0154]

[0155]

[0156] Then, in step 15, after combining steps 6, 7, 9, 12, and 14, the number of unknowns is consistent with the number of equations, so the solution can be directly obtained. In addition, since the coefficient matrix of the linear equation system contains the elastic flattening coefficient between rollers, and the elastic flattening coefficient between rollers is related to the pressure between rollers, it is necessary to iteratively calculate the pressure between rollers;

[0157] Then, in step 16, determine whether the inequality max|q′-q|<0.01 holds. The inequality 1356.966<0.01 obviously does not hold, q=q+0.1(q′-q), go to step 6, loop until the inequality 0.0095<0.01, then go to step 17;

[0158] Then, in step 17, the transverse distribution value σ of the strip front tensile stress obtained during rolling by the X-type six-high rolling mill is output. 1i ;

[0159] Finally, in step 18, according to the transverse distribution value σ of the strip pre-tension stress 1i , calculate the strip shape distribution BX when the X-type six-high rolling mill is rolling i ,See Figure 5 (b) The serial numbers of the above embodiments of the present invention are for description only and do not represent the advantages or disadvantages of the embodiments.

[0160] In the above embodiments of the present invention, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0161] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. Among them, the device embodiments described above are only schematic. For example, the division of the units can be a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of units or modules, which can be electrical or other forms.

[0162] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple units. Some or all of the units may be selected according to actual needs to achieve the purpose of the present embodiment.

[0163] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0164] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions for a computer device (which can be a personal computer, a server or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), mobile hard disk, magnetic disk or optical disk and other media that can store program codes.

[0165] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for rapid prediction of plate shape of an X-type six-high rolling mill based on a model coupling method, characterized in that: The following steps are involved: Step 1: Obtain the basic equipment parameters of the X-type six-high rolling mill and the rolling process parameters of the strip; Step 2: Divide the roller and the strip into units, a total of t units; the coordinate of the center point of each unit width is y i , i=1,2,…,t, each unit width is Δy i , i=1,2,…,t; Step 3: Solve the support roller deflection influence coefficient α bij , working roll deflection influence coefficient matrix α wij And the working roll bending influence coefficient α Fwi ; Step 4: Preset the initial value h of strip exit thickness distribution 1i ; Step 5: Preset the initial value of the pressure distribution between the rollers to q i ; Step 6: Calculate the strip plastic deformation by the strip element variation method in the three-dimensional plastic deformation model, and perform a simple deformation on the lateral displacement equation group at the node line outlet; Step 7: Solve the roller flattening influence coefficient; Step 8: List the deformation coordination equation between the rolls of the roll system; Step 9: List the force and moment balance equations of the support roll and the working roll; Step 10: From the perspective of elastic deformation of the roller system, obtain expression 1 of the strip outlet thickness distribution; Step 11: From the perspective of strip plastic deformation, obtain expression 2 of strip outlet thickness distribution; Step 12: Combine the expression 1 of the strip outlet thickness distribution in step 10 with the expression 2 of the strip outlet thickness distribution in step 11; Step 13: Based on the average thickness of the strip outlet being equal to h1, discrete integration is performed on Expression 1 of the strip outlet thickness distribution; Step 14: After discrete integration of the expression 1 of the strip outlet thickness distribution, substitute the equation on the right side of the equal sign in step 12; Step 15: After the equations in steps 6, 7, 8, 9, 12, and 14 are combined, the number of unknowns is consistent with the number of equations, and all unknowns in the linear equation system are solved; since the coefficient matrix of the linear equation system contains the elastic flattening coefficient between rollers, and the elastic flattening coefficient between rollers is related to the pressure between rollers, it is necessary to iteratively calculate the pressure between rollers; Step 16: Determine whether the calculated value q′ satisfies the inequality max|q′-q|<0.01; if not, set q=q+0.1(q′-q) and proceed to step 6; if yes, proceed to step 17; Step 17: Output the transverse distribution value σ of the strip pre-tension stress 1i ; Step 18: According to the transverse distribution value σ of the strip pre-tension stress 1i , calculate the strip shape distribution BX at the current moment i ; 2. The method for rapid prediction of plate shape of an X-type six-high rolling mill based on a model coupling method according to claim 1 is characterized in that: In step 1, the basic equipment parameters of the X-type six-high rolling mill include: the roll length, roll radius, crown, elastic modulus and Poisson's ratio of the support roll and the working roll, respectively denoted as L b , L w , R b , R w , ΔD b , ΔD w 、E b 、E w 、v b and v w , the distance between the two sides of the support point is L s , the distance between the two bending roll hydraulic cylinders of the working roll is L Fw The angle between the line connecting the center points of the cross sections of the support roll and the working roll and the vertical direction is α.

3. The method for rapid prediction of flatness of an X-type six-high rolling mill based on a model coupling method according to claim 1, characterized in that: In step 1, the rolling process parameters of the strip include the average thickness of the strip material. Average thickness of strip after rolling Width B, strip elastic modulus E s , Strip Poisson's ratio v s , Strip deformation resistance σ s , strip shear deformation resistance k s , average post-tensioning stress of the strip Average pre-tension stress of strip Working roll bending force F w , calculate the allowable error ε and the relaxation factor X.

4. The method for rapid prediction of flatness of an X-type six-high rolling mill based on a model coupling method according to claim 1, characterized in that: In step 2, the coordinate origin is selected at the left pressure support of the support roller. The roller and the strip are divided into units, a total of t units; the coordinate of the center point of the width of each unit is y i , i=1,2,…,t, each unit width is Δy i , i=1,2,…,t; where the starting unit number of the contact part between the backup roll and the working roll is t1, and the ending unit number is t2; the starting unit number of the contact part between the working roll and the strip is t3, and the ending unit number is t4; When calculating the plastic deformation of the strip, the outlet lateral displacement of the strip unit node line needs to be taken as an unknown quantity; therefore, the strip unit node lines are renumbered; the two node lines corresponding to unit t3 are numbered 0 and 1, and the two node lines corresponding to unit t4 are numbered n-1 and n, n=t4-t3+1, and the node line numbers of other units can be obtained by analogy.

5. The method for rapid prediction of flatness of an X-type six-high rolling mill based on a model coupling method according to claim 1, characterized in that: In step 6, the expression after simple transformation is: Among them, u0, u1, ...u n They represent the lateral displacement of the strip unit node line outlet, which is an unknown quantity; They represent the lateral distribution of rolling pressure, which is an unknown quantity; ψ is related to unit width, strip elastic modulus, strip Poisson's ratio, strip shear deformation resistance, neutral point thickness, work roll elastic flattening radius, friction coefficient, average friction stress of contact surface in deformation zone, thickness before rolling, reduction, deformation zone length, and stress state coefficient; represents the equivalent deformation resistance, 6. The method for rapid prediction of flatness of an X-type six-high rolling mill based on a model coupling method according to claim 1, characterized in that: In step 7, the elastic flattening influence coefficient γ between rollers i , the equation of the roller flattening amount and roller pressure distribution is: d i =c i q i ,(i=t1~t2); Among them, δ i Indicates the elastic flattening amount between rollers; q i Represents the roller pressure of the i-th unit.

7. The method for rapid prediction of flatness of an X-type six-high rolling mill based on a model coupling method according to claim 1, characterized in that: In step 8, the roll deformation coordination equation is: f wi =2cosα(f bi +d i +ΔD i ),(i=t1~t2); Among them, f w Indicates the deflection of the working roll in the vertical direction; f b It indicates the deflection of the support roll along the line connecting the center points of the support roll and the working roll. ΔD indicates the no-load gap between the rolls, i.e., the crown. ΔD i =(ΔD wi +ΔD bi ) / 2.

8. The method for rapid prediction of flatness of an X-type six-high rolling mill based on a model coupling method according to claim 1, characterized in that: In step 9, the force and moment balance equation of the working roll is: Among them, p i Represents the rolling pressure of the i-th unit.

9. The method for rapid prediction of flatness of an X-type six-high rolling mill based on a model coupling method according to claim 1, characterized in that: In step 10, the expression 1 for obtaining the strip outlet thickness distribution is: h 1i =s0+2f wi +2δ wi +ΔD i ,(i=t3~t4); Among them, δ wi Indicates the amount of elastic flattening of the working roll surface in contact with the workpiece.

10. The method for rapid prediction of flatness of an X-type six-high rolling mill based on a model coupling method according to claim 1, characterized in that: In step 11, the expression 2 for obtaining the strip outlet thickness distribution is: in, Respectively represent the average thickness of the strip at the entrance and exit, F i Represents constants related to unit width, strip elastic modulus, strip Poisson's ratio, neutral point thickness, average friction stress of contact surface in deformation zone, reduction, strip shear deformation resistance, and deformation zone length.

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