Non-iterative four-high mill plate shape forecasting method

Abstract

The invention provides a non-iterative four-high mill plate shape forecasting method, and belongs to the technical field of metallurgical rolling. The method comprises the following steps: collecting equipment parameters of a four-high rolling mill, characteristic parameters of a typical strip for rolling 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, direct solving is achieved, and no iteration is needed. Two calculation examples show that the calculation result of the non-iterative four-high mill plate shape forecasting method is well matched with that of a model coupling method, and the calculation speed is increased by about 10 times.

Description

Technical Field

[0001] The invention relates to the technical field of metallurgical rolling, and in particular to a non-iterative four-roll mill plate shape prediction method. Background Art

[0002] As competition in the global new energy raw materials market continues to intensify, how to improve the quality of copper strip has become an important challenge for manufacturers. [1] It is widely used in copper strip rolling. In the production process of copper strip, the problem of poor plate shape (straightness) is encountered many times. In order to reduce the occurrence of poor plate shape, it is necessary to effectively control the plate shape. Plate shape control technology [2] The core of the model is the flatness prediction model, that is, how to [3] , process parameters and plate shape adjustment parameters to accurately predict plate shape. Based on the plate shape prediction model, plate shape setting and feedback control can be realized to carry out rolling procedures [4] and roll profile optimization [5] . Flatness prediction model [6] It includes two mutually coupled sub-models: strip plastic deformation and roller elastic deformation. 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] Sun Zonghao. Analysis on the stability of roller system of four-roll copper strip reversible cold rolling mill[J]. Nonferrous Metal Processing, 2015, 44(02): 51-54+42.

[0005] [2] Xu Yue, Chai Tianyou, Mao Zhizhong. Research on the shape control system of four-roller reversible cold rolling mill [J]. Metallurgical Automation, 1995, (01): 8-12.

[0006] [3] Li Hong. Research on the optimal roll offset model of four-roll mill[J]. Metallurgical Equipment, 2019, (01): 26-30.

[0007] [4] Bai Zhenhua, Li Boyang, Zhao Weiquan, et al. Rolling schedule setting method for four-roll reversible narrow strip mill[J]. Journal of Iron and Steel Research, 2018, 30(06): 453-460.

[0008] [5] Wang Dongcheng, Ma Qinglong, Liu Hongmin. Research on roll profile optimization technology of cold strip skin pass mill support roll[J]. Steel, 2009, 44(08): 56-59.

[0009] [6] 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

[0010] According to the above technical problem that the four-roll mill has poor flatness (straightness) during the production process, a non-iterative four-roll mill flatness prediction method is provided. The present invention is a non-iterative four-roll mill flatness prediction method, which integrates the strip plastic deformation model and the roller system elastic deformation model into a unified linear equation group, and directly solves it without any iteration.

[0011] The technical means adopted by the present invention are as follows:

[0012] A non-iterative four-high mill shape prediction method comprises the following steps:

[0013] Step 1: Obtain the basic equipment parameters of the four-high rolling mill and the rolling process parameters of typical specification products;

[0014] Step 2: Divide the roller and the strip into t units; the coordinate of the width center point of each unit is y i , i=1,2,…,t, the width of each unit is Δy i , i=1,2,…,t;

[0015] Step 3: Solve the deflection influence coefficient of each roll; the roll deflection influence coefficient includes: working roll deflection influence coefficient α wij , support roller deflection influence coefficient α bij And the influence coefficient α of the working roll bending force on the working roll deflection Fwi ;

[0016] Step 4: Preset the initial value h of strip exit thickness distribution 1i ;

[0017] Step 5: Calculate the strip plastic deformation by the strip element variation method in the three-dimensional plastic deformation model, and deform the node line outlet lateral displacement equation group;

[0018] Step 6: Solve the simplified roller flattening influence coefficient;

[0019] Step 7: By analyzing the geometric deformation of the roll system of the four-high rolling mill, the deformation coordination equation between the working roll and the backup roll is listed;

[0020] Step 8: According to the force and moment balance, list the working roll force and moment balance equations respectively;

[0021] Step 9: From the perspective of roller system elastic deformation, obtain expression 1 of strip exit thickness distribution;

[0022] Step 10: From the perspective of strip plastic deformation, obtain expression 2 of strip outlet thickness distribution;

[0023] Step 11: Combine the expression 1 of the strip outlet thickness distribution in step 9 and the expression 2 of the strip outlet thickness distribution in step 10;

[0024] Step 12: 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 13: 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 14: After the equations in steps 5, 7, 8, 11, and 13 are combined, the number of unknowns is consistent with the number of equations, and the rolling pressure distribution, the pressure distribution between the rolls, the lateral displacement of the strip outlet, the rigid displacement, and the no-load roll gap are calculated;

[0027] Step 15: Output the transverse distribution value σ of the strip pre-tension stress 1i ;

[0028] Step 16: According to the transverse distribution value σ of the strip pre-tension stress 1i , calculate the strip shape distribution F at the current moment i ;

[0029]

[0030] Compared with the prior art, the present invention has the following advantages:

[0031] The present invention takes the pressure distribution between the rolls of the four-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, integrates the strip plastic deformation model and the roll system elastic deformation model into a unified linear equation set, and solves it directly without any iteration. Two calculation examples show that the calculation results of the non-iterative four-roll mill shape prediction method are in good agreement with the model coupling method, while the calculation speed is increased by about 10 times. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] 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.

[0033] Figure 1 It is the overall flow chart of the present invention;

[0034] Figure 2 It is a schematic diagram of the segmented roll system of a four-roller rolling mill of the present invention;

[0035] Figure 3 It is a corresponding relationship diagram between the unit node line number and the unit number of the present invention;

[0036] Figure 4 It is the lateral distribution diagram of the plate shape of the present invention; among them, (a) is Example 1; (b) is Example 2. DETAILED DESCRIPTION

[0037] 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.

[0038] 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.

[0039] like Figures 1 to 4 As shown, the present invention provides a non-iterative four-high mill shape prediction method, comprising the following steps:

[0040] Step 1: Collection of basic equipment parameters of the four-high rolling mill: working roll body radius R w , support roller body radius R b , elastic modulus of working roll E w , elastic modulus of support roller E b , Poisson's ratio of working roll w , Poisson's ratio of the support roller b , the distance between the two sides of the support point is L s , working roller length L w , support roller body length L b , roll crown ΔD of working roll and backup roll wbi , working roll bending hydraulic cylinder distance L Fw And the working roll bending force F w .

[0041] At the same time, the rolling process parameters of typical specifications of products are collected, mainly including the average thickness of the incoming strip 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 And the average pre-tension stress of the strip

[0042] Step 2: Unit division, such as Figure 2 As shown. The origin of the coordinate is selected at the midpoint of the strip. 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). The starting unit number of the contact part between the working roll and the strip is t5, and the ending unit number is t6. 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 As shown. The two node lines corresponding to unit t5 are numbered 0 and 1, and the two node lines corresponding to unit t6 are numbered n-1 and n, (n=t6-t4+1). The node line numbers of other units can be obtained by analogy;

[0043] Step 3: Solve the deflection influence coefficient of each roll, including: Calculate the deflection influence coefficient α of the working roll wij , support roller deflection influence coefficient α bij And the influence coefficient α of the working roll bending force on the working roll deflection Fwi ;

[0044] Step 4: Given the initial value h of the strip exit thickness distribution 1i ;

[0045] Step 5: 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 lateral displacement equation group at the node line outlet:

[0046]

[0047] 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 respectively; represents the equivalent deformation resistance,

[0048] Step 6: A non-iterative four-high mill shape prediction method according to claim 1, characterized in that in step 6, the elastic flattening influence coefficient ξ between the simplified working roll and the backup roll is calculated wbi ;

[0049]

[0050] The equation for the flattening amount between the rollers and the pressure distribution between the rollers is:

[0051] δ wbi =ξ wbi q wbi ,(i=1~t);

[0052] Among them, q wbi Indicates the pressure distribution between the working roll and the backup roll;

[0053] Step 7: By analyzing the geometric deformation of the four-high mill roll system, the deformation coordination equation between the working roll and the backup roll can be listed:

[0054] f wi =f bi +δ wbi +ΔD wbi ,(i=1~t);

[0055] Among them, f wi is the deflection of the working roll on unit i, f bi is the deflection of the support roller on unit i;

[0056] Step 8: According to the force and moment balance, the working roll force and moment balance equation can be listed as follows:

[0057]

[0058] Step 9: From the perspective of elastic deformation of the roller system, the expression for the strip outlet thickness distribution is as follows:

[0059] h 1i =s0+2f wi +2δ wi +ΔD wi ,(i=t5~t6);

[0060] Where: s0 is the no-load roll gap value, ΔDwi is the working roll profile distribution value, δ wi is the elastic flattening amount between the working roll and the strip, β ij is the elastic flattening influence coefficient of the strip on the working roll;

[0061] Step 10: From the perspective of strip plastic deformation, the expression for strip outlet thickness distribution is as follows:

[0062]

[0063]

[0064] In the formula: Respectively represent the average thickness of the strip at the entrance and exit, F i It is related to the unit width, strip elastic modulus, strip Poisson's ratio, neutral point thickness, average friction stress of the contact surface in the deformation zone, reduction, strip shear deformation resistance and deformation zone length;

[0065] Step 11: Combine step 9 and step 10 to get:

[0066]

[0067] Among them, C7 and C8 are respectively the vertical rigid displacements of the left and right end axes of the working roll body;

[0068] Step 12: According to the average thickness of the strip outlet is equal to This condition, the left and right sides of the equation in step 9 are discretely integrated, and the integral on the left side of the equation is:

[0069]

[0070] Step 13: After integrating the right side of the equation in step 9, substitute the equation in step 12 to obtain:

[0071]

[0072] Step 14: After combining the equations in steps 5, 6, 8, 11, and 13, the number of unknowns is the same as the number of equations, so they can be solved directly;

[0073] Step 15: Output the transverse distribution value σ of the strip front tensile stress during rolling by the four-high rolling mill 1i ;

[0074] Step 16: According to the transverse distribution value σ of the strip pre-tension stress 1i , calculate the strip shape distribution F when the four-high rolling mill rolls this strip i :

[0075]

[0076] Example 1

[0077] Take a four-roll mill in a factory as an example. Figure 1 The overall calculation flow chart of the non-iterative four-high mill shape prediction method is shown in FIG. First, in step 1, the basic equipment parameters of the four-high mill are collected: the radius R of the working roll body w =140mm, support roller body radius R b =325mm, working roll elastic modulus E w =236GPa, elastic modulus of support roller E b =210GPa, 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 =1450mm, working roll body length L w =800mm, support roller body length L b =800mm, roll crown of working roll and backup roll ΔD wbi , working roll bending hydraulic cylinder distance L Fw =1370mm and working roll bending force F w =10000N;

[0078] 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 Width B = 420 mm, elastic modulus of strip E s =105GPa, strip Poisson's ratio υ s =0.35, strip deformation resistance σ s =300MPa, strip shear deformation resistance k s =173.1MPa, average post-tension stress of strip And the average pre-tension stress of the strip

[0079] 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 midpoint of the strip. The roller and the strip are divided into 81 units. The coordinate of the center point of each unit width is y i (i=1,2,…,81), each unit width is ΔY i (I=1,2,…,81). The starting unit number of the contact part between the working roll and the strip is 20, and the ending unit number is 62. 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 As shown. The two node lines corresponding to unit 20 are numbered 0 and 1, the two node lines corresponding to unit 62 are numbered 42 and 43, and the node line numbers of other units can be obtained by analogy;

[0080] Then, in step 3, the deflection influence coefficient of each roll is solved, including: calculating the deflection influence coefficient α of the working roll wij , support roller deflection influence coefficient α bij And the influence coefficient α of the working roll bending force on the working roll deflection Fwi ;

[0081] Then, in step 4, the initial value H of the strip exit thickness distribution is given 1i ;

[0082] Then, in step 5, 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:

[0083]

[0084] Then, in step 6, the simplified elastic flattening influence coefficient ξ between the working roll and the support roll is calculated wbi ;

[0085]

[0086] The equation for the flattening amount between the rollers and the pressure distribution between the rollers is:

[0087] δ wbi =ξ wbi q wbi ,(i=1~81);

[0088] Then, in step 7, the deformation coordination equation between the working roll and the backup roll is:

[0089] f wi =f bi +δ wbi +ΔD wbi ,(i=1~81);

[0090] Then, in step 8, based on the force and moment balance, the work roll force and moment balance equation can be listed as follows:

[0091]

[0092] Then, in step 9, from the perspective of elastic deformation of the roller system, the expression of the strip outlet thickness distribution is as follows:

[0093] h 1i =s0+2f wi +2δ wi +ΔDwi ,(i=20~62);

[0094] Subsequently, in step 10, from the perspective of strip plastic deformation, the expression for the strip outlet thickness distribution is as follows:

[0095]

[0096] Then, in step 11, step 9 is combined with step 10 to obtain:

[0097]

[0098] Then, in step 12, according to the strip outlet average thickness equal to This condition, the left and right sides of the equation in step 9 are discretely integrated, and the integral on the left side of the equation is:

[0099]

[0100] Then, in step 13, after integrating the right side of the equation in step 9, substitute the equation in step 12 to obtain:

[0101]

[0102] Then, in step 14, after combining steps 5, 6, 8, 11, and 13, the number of unknowns is the same as the number of equations, so they can be solved directly;

[0103] Then, in step 15, the transverse distribution value σ of the strip front tensile stress obtained during rolling by the four-high rolling mill is output. 1i ;

[0104] Finally, in step 16, according to the transverse distribution value σ of the strip pre-tension stress 1i , calculate the strip shape distribution F when the four-high rolling mill rolls this strip i ,See Figure 4 (a).

[0105] Example 2

[0106] Take a four-roll mill in a factory as an example. Figure 1 The overall calculation flow chart of the non-iterative four-high mill shape prediction method is shown in FIG. First, in step 1, the basic equipment parameters of the four-high mill are collected: the radius R of the working roll body w =140mm, support roller body radius R b =325mm, working roll elastic modulus E w =236GPa, elastic modulus of support roller E b =210GPa, 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 =1450mm, working roll body length L w =800mm, support roller body length L b =800mm, roll crown of working roll and backup roll ΔD wbi , working roll bending hydraulic cylinder distance L Fw =1370mm and working roll bending force F w =20000N;

[0107] 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 Width B = 630 mm, strip elastic modulus E s =105GPa, strip Poisson's ratio v s =0.35, strip deformation resistance σ s =300MPa, strip shear deformation resistance k s =173.1MPa, average post-tension stress of strip And the average pre-tension stress of the strip

[0108] 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 midpoint of the strip. The roller and the strip are divided into 81 units. The coordinate of the center point of each unit width is y i (i=1,2,…,81), each unit width is Δy i (i=1,2,…,81). The starting unit number of the contact part between the working roll and the strip is 10, and the ending unit number is 72. 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 As shown. The two node lines corresponding to unit 10 are numbered 0 and 1, the two node lines corresponding to unit 72 are numbered 62 and 63, and the node line numbers of other units can be deduced by analogy;

[0109] Then, in step 3, the deflection influence coefficient of each roll is solved, including: calculating the deflection influence coefficient α of the working roll wij , support roller deflection influence coefficient α bij And the influence coefficient α of the working roll bending force on the working roll deflection Fwi ;

[0110] Then, in step 4, the initial value h of the strip exit thickness distribution is given 1i ;

[0111] Then, in step 5, 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:

[0112]

[0113] Then, in step 6, the simplified elastic flattening influence coefficient ξ between the working roll and the support roll is calculated wbi ;

[0114]

[0115] The equation for the flattening amount between the rollers and the pressure distribution between the rollers is:

[0116] δ wbi =ξ wbi q wbi ,(i=1~81);

[0117] Then, in step 7, the deformation coordination equation between the working roll and the backup roll is:

[0118] f wi =f bi +δ wbi +ΔD wbi ,(i=1~81);

[0119] Then, in step 8, based on the force and moment balance, the work roll force and moment balance equation can be listed as follows:

[0120]

[0121] Then, in step 9, from the perspective of elastic deformation of the roller system, the expression of the strip outlet thickness distribution is as follows:

[0122] h 1i =s0+2f wi +2δ wi +ΔD wi ,(i=10~72);

[0123] Subsequently, in step 10, from the perspective of strip plastic deformation, the expression for the strip outlet thickness distribution is as follows:

[0124]

[0125] Then, in step 11, step 9 is combined with step 10 to obtain:

[0126]

[0127] Then, in step 12, according to the strip outlet average thickness equal to This condition, the left and right sides of the equation in step 9 are discretely integrated, and the integral on the left side of the equation is:

[0128]

[0129] Then, in step 13, after integrating the right side of the equation in step 9, substitute the equation in step 12 to obtain:

[0130]

[0131] Then, in step 14, after combining 5, 6, 8, 11, and 13, the number of unknowns is the same as the number of equations, so they can be solved directly;

[0132] Then, in step 15, the transverse distribution value σ of the strip front tensile stress obtained during rolling by the four-high rolling mill is output. 1i ;

[0133] Finally, in step 16, according to the transverse distribution value σ of the strip pre-tension stress 1i , calculate the strip shape distribution F when the four-high rolling mill rolls this strip i ,See Figure 4 (b).

[0134] The serial numbers of the above embodiments of the present invention are only for description and do not represent the advantages and disadvantages of the embodiments. 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, please refer to the relevant description of other embodiments. In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways.

[0135] 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 non-iterative four-high mill shape prediction method, characterized in that: The following steps are involved: Step 1: Obtain the basic equipment parameters of the four-high rolling mill and the rolling process parameters of typical specification products; Step 2: Divide the roller and the strip into t units; the coordinate of the width center point of each unit is y i , i = 1, 2, ..., t, the width of each unit is Δy i , i=1,2,…,t; Step 3: Solve the deflection influence coefficient of each roll; the roll deflection influence coefficient includes: working roll deflection influence coefficient α wij , support roller deflection influence coefficient α bij And the influence coefficient α of the working roll bending force on the working roll deflection Fwi ; Step 4: Preset the initial value h of strip exit thickness distribution 1i ; Step 5: Calculate the strip plastic deformation by the strip element variation method in the three-dimensional plastic deformation model, and deform the node line outlet lateral displacement equation group; Step 6: Solve the simplified roller flattening influence coefficient; Step 7: By analyzing the geometric deformation of the roll system of the four-high rolling mill, the deformation coordination equation between the working roll and the backup roll is listed; Step 8: According to the force and moment balance, list the working roll force and moment balance equations respectively; Step 9: From the perspective of roller system elastic deformation, obtain expression 1 of strip exit thickness distribution; Step 10: From the perspective of strip plastic deformation, obtain expression 2 of strip outlet thickness distribution; Step 11: Combine the expression 1 of the strip outlet thickness distribution in step 9 and the expression 2 of the strip outlet thickness distribution in step 10; Step 12: According to the average thickness of the strip outlet is equal to Performing discrete integration on Expression 1 of the strip outlet thickness distribution; Step 13: 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 14: After the equations in steps 5, 7, 8, 11, and 13 are combined, the number of unknowns is consistent with the number of equations, and the rolling pressure distribution, the pressure distribution between the rolls, the lateral displacement of the strip outlet, the rigid displacement, and the no-load roll gap are calculated; Step 15: Output the transverse distribution value σ of the strip pre-tension stress 1i ; Step 16: According to the transverse distribution value σ of the strip pre-tension stress 1i , calculate the strip shape distribution F at the current moment i ; 2. A non-iterative four-high mill shape prediction method according to claim 1, characterized in that: In step 1, the basic equipment parameters of the four-high rolling mill include: the radius R of the working roll body w , support roller body radius R b , elastic modulus of working roll E w , elastic modulus of support roller E b , Poisson's ratio of working roll w , Poisson's ratio of the support roller b , the distance between the two sides of the support point is L s , working roller length L w , support roller body length L b , roll crown ΔD of working roll and backup roll wbi , working roll bending hydraulic cylinder distance L Fw And the working roll bending force F w .

3. A non-iterative four-high mill shape prediction method according to claim 1, characterized in that: In step 1, the rolling process parameters of the typical specification products include: the average thickness of the incoming strip 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 And the average pre-tension stress of the strip 4. A non-iterative four-high mill shape prediction method according to claim 1, characterized in that: In step 2, the coordinate origin is set at the midpoint of the strip; 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 working roll and the strip is t5, and the ending unit number is t6; when calculating the plastic deformation of the strip, the outlet lateral displacement of the strip unit node line is taken as an unknown quantity; therefore, the strip unit node lines are renumbered; the two node lines corresponding to unit t5 are numbered 0 and 1, and the two node lines corresponding to unit t6 are numbered n-1 and n, n=t6-t5+1, and the node line numbers of other units are obtained by analogy.

5. A non-iterative four-high mill shape prediction method according to claim 1, characterized in that: In step 5, the transformed expression 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, pre-rolling thickness, reduction, deformation zone length and stress state coefficient; represents the equivalent deformation resistance, 6. A non-iterative four-high mill shape prediction method according to claim 1, characterized in that: In step 6, the elastic flattening influence coefficient ξ between the simplified working roll and the support roll is calculated. wbi ; The equation for the flattening amount between the rollers and the pressure distribution between the rollers is: d wbi =ξ wbi q wbi ,(i=1~t); Among them, q wbi Indicates the pressure distribution between the working roll and the backup roll.

7. A non-iterative four-high mill shape prediction method according to claim 1, characterized in that: In step 9, the expression 1 for obtaining the strip outlet thickness distribution is: h 1i =s0+2f wi +2δ wi +ΔD wi ,(i=t5~t6)。 8. A non-iterative four-high mill shape prediction method according to claim 1, characterized in that: In step 10, 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 It is related to the unit width, strip elastic modulus, strip Poisson's ratio, neutral point thickness, average friction stress of the contact surface in the deformation zone, reduction, strip shear deformation resistance and deformation zone length.

Images