Method for controlling roll consumption by using roll shape of back-up roll of four-roll mill

Abstract

The invention provides a method for controlling roll consumption by using roll types of support rolls of a four-roll mill. The method comprises the following steps executed by a computer: collecting equipment, strips and rolling process parameters; determining iteration parameters of the calculation process; calculating a roll shape curve of the support roll through the roll shape parameters; dividing the length of a roller body and the width of a strip, and defining relevant parameters of a calculation process; calculating a load and deflection change influence function and a supporting force and deflection change influence function; calculating an inter-roller pressure value of each segment after segmentation; calculating an inter-roller pressure optimization function value; judging whether the roll shape is not the original roll shape or not and whether the optimization function value difference is smaller than a calculation error value or not; judging whether the height is not the initial shoulder cutting height and whether the difference value of the optimization function values is smaller than a calculation error value; outputting shoulder cutting height and shoulder cutting length results, and calculating the depth of the fatigue hardening layer of the roller. By optimizing the roller shape curve and calculating the depth of the fatigue hardening layer of the roller, the roller consumption of the supporting roller is reduced, and the economic benefit is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of maleic anhydride production, and in particular relates to a method for controlling roll consumption by utilizing the roll profile of a support roll of a four-roller rolling mill. Background Art

[0002] Effectively controlling the roll gap shape is crucial for adjusting the shape of hot-rolled strip steel. In the load-bearing roll gap shape and the initial equivalent convexity, the original roll shape of the roll is the most critical influencing factor. Adjusting the roll shape is the most sensitive, important and direct method to achieve shape control. At present, most domestic hot-rolled strip production sites have adopted this method to improve product quality. Therefore, it is of great significance to study and design the roll shape and establish a roll shape system suitable for hot-rolled strip steel shape control.

[0003] At present, the research mainly focuses on improving the stability of the rolling process and product quality through the design methods and devices of different types of rolls. The methods mentioned in various literatures include obtaining roll parameters, determining roll curve functions, and designing the target roll profile of support rolls or working rolls to solve problems that may occur during the rolling process, such as edge wave defects, uneven wear in the contact area, and reduced service life. These design methods improve the contact pressure distribution between rolls, reduce harmful contact and stress concentration at the edge of the rolls, achieve uniform wear of the rolls, and help extend the service life of the rolls and mechanical equipment. However, the research on the depth of the fatigue hardened layer of the rolls after the roll profile of the four-roll mill is optimized has not been involved.

[0004] Therefore, taking into account the rolling characteristics of the hot rolling finishing mill and the influence of factors such as rolling pressure and strip width, a method for controlling roll consumption by using the support roll profile of a four-roll mill is specially designed on the basis of combining the roll wear and fatigue mechanism model, the roll thermal convexity model, and the lateral distribution model of the inter-roll pressure and rolling force. By adjusting the roll profile curve parameters of the support roll, the peak inter-roll pressure during rolling is reduced, and the risk of roll spalling accidents is reduced. At the same time, the depth of the fatigue hardened layer after roll profile optimization is calculated, which provides more reliable guidance for the amount of grinding of the support roll, reduces unnecessary losses during grinding, thereby reducing the roll consumption of the support roll and improving the economic benefits of on-site strip production. Summary of the invention

[0005] In order to solve the above problems mentioned in the prior art, the present invention provides a method for controlling roll consumption by utilizing the roll profile of the support roll of a four-roll rolling mill.

[0006] The present invention adopts the following technical solution:

[0007] A method for controlling roll wear using a four-high rolling mill support roll profile, comprising the following steps executed by a computer:

[0008] (A) According to the roll profile curve of the hot rolling four-high mill support roll, the equipment parameters, belt parameters and rolling process parameters of the four-high mill are collected: mainly the radius R of the working roll of the specific stand w , Working roll body length l w , Support roller radius R b , support roller body length l b , strip width B, average strip inlet thickness H, average strip outlet thickness h, rolling pressure P, roller profile power α;

[0009] (B) Determine the iterative parameters of the calculation process: including the initial shoulder length l L0 , initial shoulder length l H0 , shoulder cutting length iteration step Δ L , shoulder cutting height iteration step length Δ H , and the calculation error ε;

[0010] (C) calculating the support roller profile curve by using the roller profile parameters to obtain the support roller convexity;

[0011] (D) dividing the roller body length and the strip width and defining relevant parameters of the calculation process;

[0012] (E) Calculate the influence function of load and deflection change and the influence function of support force and deflection change;

[0013] (F) Calculate the roller pressure value of each segment after segmentation;

[0014] (G) Calculate the optimized function value of the pressure between the rollers. By uniformly distributing the pressure between the rollers, reducing the roller consumption and the peak value of the contact pressure between the rollers, the service life of the support rollers can be increased. The objective function can be expressed as:

[0015] f1(x)=(q max -q avg ) / q avg

[0016] Where: q max is the maximum inter-roller pressure per unit width along the roller body; q avg is the average roller pressure per unit width.

[0017] (H) Determine whether the roll type of the support roll is not the original one and whether |f1-f0|<ε during the calculation process. If it is the original roll type, let l L = l L0 , l H = l H0 , f0=f1, if the calculation error is not satisfied, let l L = l L +Δ L , f0=f1, go to step (C); if all are true, go to step (I);

[0018] (I) Determine whether the calculation process is the initial shoulder cutting height and whether |f1-f0|<ε. If one of the items is not true, let l H = l H +Δ H , f0=f1, go to step (C), and do not go to step (H) during the cycle; if all are true, go to step (J);

[0019] (J) Output shoulder length l L and shoulder height l H The final calculation results are used to calculate the roller fatigue hardening layer depth curve based on the inter-roller pressure value obtained according to the optimized roller profile parameters.

[0020] Furthermore, the calculation model of the support roller profile curve in step C) is as follows:

[0021]

[0022] Where: L b —Length of support roller; R b — Radius of support roller; l L , l H —The length and depth of the shoulder cut of the support roller after roller profile optimization; α—The power of the roller profile curve optimization target.

[0023] Further, in step D), the roll length of the support roll and the lateral division of the non-zero rolling pressure portion are divided into 2a+1 segments and 2b+1 segments respectively; let n2=2a+1 and n1=2b+1, which are the total number of lateral segments of the roll length of the support roll and the non-zero rolling pressure portion respectively; in these segments, select two specific segments i,j∈{1,2,...,2a+1} respectively, and the influence function a of the deflection of the working roll and the support roll of the i segment caused by the load of the j segment ij 、b ij , the influence function of the left and right support forces on the deflection of the i-th section working roll and support roll The pressure value P between the rollers in the jth section j , rolling pressure value P' in the jth section j , the total rolling force P for a specific stand.

[0024] Further, in step E), the influence function a of the change in deflection of the i-th section working roll and the support roll caused by the j-th section load is calculated based on the influence function model. ij 、b ij , and the influence function of the left and right support forces on the deflection change of the support roller And the calculation model is as follows:

[0025]

[0026] Where: k = 10 / 9,

[0027] Furthermore, the inter-roller pressure value P of each section is calculated based on the metal plastic deformation model and the roller system elastic deformation model. i , the calculation model is as follows:

[0028]

[0029] Where: K is the flexibility coefficient of the working roll and the support roll being pressed against each other, F is the process function, β is the rigid rotation angle of the working roll relative to the support roll, and after solving, β=0, q * is the contact pressure per unit roller length, B is half of the contact width of the two rollers, ν1 and ν2 are the Poisson's ratios on the two cylinders (rollers), and E1 and E2 are the Young's moduli on the two cylinders.

[0030] Furthermore, the calculation model of the roller fatigue hardening layer depth curve in step J) is as follows:

[0031]

[0032] Where: b is the half width of the contact surface, mm; Z is the depth of the roller fatigue layer, mm; P is the line contact pressure, kg / mm; d w ,d b are the working roll diameter and the backup roll diameter, mm; E1 and E2 are the elastic moduli of the working roll and the backup roll, respectively.

[0033] The technical solution provided by the present invention has the following beneficial effects:

[0034] The present invention controls the roll profile curve of the support roll of the four-roll mill, comprehensively considers production parameters such as the diameter of the working roll, the diameter and length of the support roll, the entry thickness and exit thickness of the strip, and adjusts the roll profile curve parameters of the support roll to reduce the peak pressure between the rolls during the rolling process, thereby reducing the risk of roll peeling accidents. At the same time, the depth of the fatigue layer of the roll after the roll profile is optimized is calculated, and more reliable guidance is provided for the grinding amount of the support roll off the machine, thereby reducing unnecessary losses in grinding and reducing the support roll consumption, thereby providing better economic benefits for enterprise production.

[0035] Figure Description:

[0036] Figure 1 It is a flow chart of a method for controlling roll consumption by using the roll profile of a four-roller rolling mill support roll according to the present invention;

[0037] Figure 2 To optimize the pressure curve between the front rollers;

[0038] Figure 3 To optimize the pressure curve between the rear rollers;

[0039] Figure 4 To optimize the roller profile curve;

[0040] Figure 5 To optimize the fatigue hardening layer depth curve of the rear support roller;

[0041] Figure 6 To optimize the pressure curve between the front rollers;

[0042] Figure 7 To optimize the pressure curve between the rollers

[0043] Figure 8 To optimize the roller profile curve;

[0044] Fig. 9 This is the fatigue hardening layer depth curve of the optimized support roller. DETAILED DESCRIPTION

[0045] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions of the embodiments of the present invention. The following embodiments are only used to more clearly illustrate the technical solutions of the present invention, and are therefore only used as examples, and cannot be used to limit the scope of protection of the present invention.

[0046] The following is an example of a hot rolling finishing mill. Figure 1 The application of the method for controlling roll consumption by utilizing the roll profile of the support roll of a four-roll mill described in the present invention is further specifically described in the embodiments.

[0047] Embodiment 1:

[0048] Taking a product with a steel grade of Q235B and a specification of 310 mm×1.5 mm (width×thickness) as an example, the method of controlling roll consumption by utilizing the roll profile of the support roll of a four-roll rolling mill described in the present invention is described in detail.

[0049] A) First, collect the relevant parameters of the rolling process, mainly the radius R of the working roll of the specific stand w =325mm, working roll body length L w =650mm, support roller radius R b =325mm, support roller body length L b =670mm, strip width b=310mm, average strip entrance thickness H=28mm, average strip exit thickness h=16.8mm, rolling pressure P=380t and roller profile power α=4.

[0050] B) Then determine the calculation process iteration parameters, including the initial shoulder length l L0 =10mm, initial shoulder height l H0 =0.1mm, shoulder cutting length iteration step ΔL =10mm, shoulder height iteration step Δ H =0.05mm, and calculation error ε=0.00001.

[0051] C) Then calculate the support roller profile curve through the roller profile parameters to obtain the support roller convexity. The calculation model is as follows:

[0052]

[0053] Where: L b —Length of support roller; R b — Radius of support roller; l L , l H —The length and depth of the shoulder cut of the support roller after the roller profile is optimized; α—The power of the roller profile curve optimization target. The first step of iterative calculation is the original roller profile. The support roller of the machine frame is a flat roller, so the roller profile curve is a straight line with a height of 325mm;

[0054] D) defining the relevant parameters of the rolling process, including the length of the support roll and the transverse division of the non-zero rolling pressure section, dividing these into 2a+1 sections and 2b+1 sections respectively;

[0055] In order to simplify the calculation, let n2 = 2a + 1 and n1 = 2b + 1, which are the total number of transverse segments of the support roll body length and the non-zero rolling pressure. In these segments, two specific segments i, j ∈ {1, 2, ..., 2a + 1} are selected, and the influence function a of the deflection of the working roll and support roll in the i segment caused by the load of the j segment is ij 、b ij , the influence function of the left and right support forces on the deflection of the i-th section working roll and support roll The j-th roller pressure value P j , rolling pressure value P' in the jth section j , the total rolling force P for a particular stand;

[0056] E) Based on the influence function model, the influence function a of the change in the deflection of the i-th section working roll and support roll caused by the j-th section load is calculated. ij 、b ij , and the influence function of the left and right support forces on the change of support roller deflection And the calculation model is as follows:

[0057]

[0058] Where: k = 10 / 9,

[0059] F) Then, the inter-roller pressure value P of each section is calculated according to the metal plastic deformation model and the roller system elastic deformation model. iWhen the roller type is the original roller type, the roller pressure value P of each section i =[10.09, 9.95, 9.82, 9.71, 9.61, 9.52, 9.43, 9.35, 9.28, 9.21, 9.15, 9.09, 9.04, 8.99, 8.95, 8.92, 8.89, 8.87, 8.85, 8.84, 8.84, 8.85, 8.87, 8.89, 8.92, 8.95, 8.99, 9.04, 9.09, 9.15, 9.21, 9.28, 9.35, 9.43, 9.52, 9.61, 9.71, 9.82, 9.95, 10.09]t, the calculation model is as follows:

[0060]

[0061] Where: K is the flexibility coefficient of the working roll and the support roll being pressed against each other, F is the process function, β is the rigid rotation angle of the working roll relative to the support roll, and after solving, β=0, q * is the contact pressure per unit roller length, B is half of the contact width between the two rollers, ν1 and ν2 are the Poisson's ratios on the two cylinders (rollers), and E1 and E2 are the Young's moduli on the two cylinders;

[0062] G) Then calculate the optimization function value of the pressure between the rollers. In the case of the original roller profile, the optimization function value of the pressure between the rollers is f1(x) = 0.089. By uniformly distributing the pressure between the rollers, reducing the roller consumption and the peak value of the contact pressure between the rollers, the service life of the support rollers can be increased. The objective function can be expressed as:

[0063] f1(x)=(q max -q avg ) / q avg

[0064] Where: q max is the maximum inter-roller pressure per unit width along the roller body; q avg is the average inter-roller pressure per unit width;

[0065] H) Then determine whether the calculation process is not the original support roller profile and whether |f1-f0|<ε; because the first step of iterative calculation is the original roller profile, the condition is not met, and enter step 3) for the next iterative calculation, and let the roller profile curve parameters be the initial roller profile curve parameters; through iterative calculation, the optimized shoulder cutting length is finally obtained as l L =100mm.

[0066] I) Determine whether the shoulder cutting height is the initial shoulder cutting height and whether |f1-f0|<ε during the calculation process; at this time, the shoulder cutting height is the initial shoulder cutting height value, so the condition is not met, and the process goes to step C) for the next iterative calculation, and the shoulder cutting height is increased by one iteration step, that is, 0.05mm, and step H is not performed in the subsequent loop steps). Through iterative calculation, the optimized shoulder cutting height is finally obtained as l H =0.2mm, at this time the optimization function value of the pressure between rollers is reduced from 0.089 of the initial roller shape to 0.037.

[0067] J) Final output shoulder cutting length l L =100mm and shoulder height l H =0.2mm is taken as the final calculation result, and the optimized roller curve is R=[324.80, 324.86, 324.91, 324.94, 324.97, 324.98, 325.00, 325.00, 325, 00, 325.00, 325.00, 325.00, 325.00, 325.00, 325.00, 325.00, 325.00, 325.00, 325.00, 325.00, 325.00 0, 325, 00, 325.00, 325.00, 325.00, 325.00, 325, 00, 325.00, 325.00, 325.00, 325.00, 325, 00, 325.00, 325.00, 325, 00, 325.00, 324.98, 324.97, 324.94, 924.91, 324.86, 324.80] mm, and the roller pressure value P obtained according to the optimized roller parameters i=[9.47, 9.56, 9.61, 9.61, 9.59, 9.56, 9.53, 9.45, 9.37, 9.30, 9.24, 9.18, 9.13, 9.08, 9.04, 9.01, 8.98, 8.96, 8.94, 8.93, 9.93, 9.93, 9.94, 8.96, 8.98 , 9.01, 9.04, 9.08, 9.13, 9.18, 9.24, 9.30, 9.37, 9.45, 9.53, 9.56, 9.59, 9.61, 9.61, 9.56, 9.47]t, the calculated roller fatigue hardening layer depth curve is h = [0.583, 0.586, 0.587, 0.587, 0. 587, 0.585, 0.585, 0.582, 0.580, 0.578, 0.576, 0.574, 0.572, 0.571, 0.569, 0.568, 0.567, 0.567, 0.566, 0.566, 0.566, 0.566, 0.566, 0.567, 0.567, 0.568, 0.569, 0.571, 0.572, 0.574, 0.576, 0.578, 0.580, 0.582, 0.525, 0.585, 0.587, 0.587, 0.587, 0.586, 0.583] mm, provides guidance for the grinding amount of the backup roller after the roll shape is optimized. The calculation model is as follows:

[0068]

[0069] Where: b is the half width of the contact surface, mm; Z is the depth of the roller fatigue layer, mm; P is the line contact pressure, kg / mm; d w ,d b are the working roll diameter and the backup roll diameter, mm; E1 and E2 are the elastic moduli of the working roll and the backup roll, respectively.

[0070] The invention controls the roll profile curve of the support roll of the four-high rolling mill, comprehensively considers production parameters such as the diameter of the working roll, the diameter and length of the support roll, the inlet thickness and outlet thickness of the strip, and adjusts the roll profile curve parameters of the support roll to reduce the peak pressure between the rolls during the rolling process and reduce the risk of roll peeling accidents. Figure 2 To optimize the pressure curve between the front rollers, Figure 3 The pressure curve between the rolls is optimized. At the same time, the fatigue layer depth of the roll after roll type optimization is calculated, which provides more reliable guidance for the grinding amount of the support roll, reduces unnecessary losses in grinding, reduces the consumption of the support roll, and thus provides better economic benefits for the production of enterprises. Figure 4 To optimize the rear roll profile, Figure 5 This is the fatigue hardening layer depth curve of the optimized support roller.

[0071] Embodiment 2:

[0072] Taking a product with a steel grade of Q235D and a specification of 350 mm×2.0 mm (width×thickness) as an example, the method of controlling roll consumption by utilizing the roll profile of the support roll of a four-roll mill described in the present invention is described in detail.

[0073] A) First, collect the relevant parameters of the rolling process, mainly the radius R of the working roll of the specific stand w =325mm, working roll body length L w =650mm, support roller radius R b =325mm, support roller body length L b =670mm, strip width b=350mm, average strip entrance thickness H=16.8mm, average strip exit thickness h=10.42mm, rolling pressure P=345t and roller profile power α=4.

[0074] B) Then determine the calculation process iteration parameters, including the initial shoulder length l L0 =10mm, initial shoulder length l H0 =0.1mm, shoulder cutting length iteration step Δ L =10mm, shoulder height iteration step Δ H =0.05mm, and calculation error ε=0.00001.

[0075] C) Then calculate the support roller profile curve through the roller profile parameters to obtain the support roller convexity. The calculation model is as follows:

[0076]

[0077] Where: L b —Length of support roller; R b — Radius of support roller; l L , l H —The length and depth of the shoulder cut of the support roller after the roll shape optimization; α—The power of the roll shape curve optimization target. The first step of iterative calculation is the original roll shape. The support roller of the machine frame is a flat roll, so the roll shape curve is a straight line with a height of 325mm.

[0078] D) Then define the relevant parameters of the rolling process, including the roll length of the support roll and the lateral segmentation of the non-zero rolling pressure, which are divided into 2a+1 segments and 2b+1 segments respectively. In order to simplify the calculation, let n2 = 2a+1 and n1 = 2b+1, which are the total number of lateral segments of the roll length of the support roll and the non-zero rolling pressure, respectively. Among these segments, select two specific segments i, j∈{1,2,...,2a+1}, and the influence function a of the deflection of the working roll and support roll in segment i caused by the load of segment j is ij 、bij , the influence function of the left and right support forces on the deflection of the i-th section working roll and support roll The pressure value P between the rollers in the jth section j , rolling pressure value P' in the jth section j , the total rolling force P for a specific stand.

[0079] E) Then, based on the influence function model, the influence function a of the deflection change of the i-th section working roll and support roll caused by the j-th section load is calculated. ij 、b ij , and the influence function of the left and right support forces on the deflection change of the support roller And the calculation model is as follows:

[0080]

[0081] Where: k = 10 / 9,

[0082] F) Then calculate the inter-roller pressure value P of each section according to the metal plastic deformation model and the roller system elastic deformation model i When the roller type is the original roller type, the roller pressure value P of each section i =[9.12, 9.00, 8.90, 8.80, 8.71, 8.63, 8.56, 8.49, 8.42, 8.36, 8.31, 8.26, 8.22, 8.18, 8.14, 8.11, 8.09, 8.07, 8.06, 8.05, 8.05, 8.05, 8.06, 8.07, 8.09, 8.11, 8.14, 8.18, 8.22, 8.26, 8.31, 8.36, 8.42, 8.49, 8.56, 8.63, 8.71, 8.80, 8.90, 9.00, 9.12]t, the calculation model is as follows:

[0083]

[0084] Where: K is the flexibility coefficient of the working roll and the support roll being pressed against each other, F is the process function, β is the rigid rotation angle of the working roll relative to the support roll, and after solving, β=0, q * is the contact pressure per unit roller length, B is half of the contact width of the two rollers, ν1 and ν2 are the Poisson's ratios on the two cylinders (rollers), and E1 and E2 are the Young's moduli on the two cylinders.

[0085] G) Calculate the optimized function value of the pressure between the rollers. In the case of the original roller profile, the optimized function value of the pressure between the rollers is f1(x) = 0.084. By uniformly distributing the pressure between the rollers, reducing the roller consumption and the peak value of the contact pressure between the rollers, the service life of the support rollers can be increased. The objective function can be expressed as:

[0086] f1(x)=(q max -q avg ) / q avg

[0087] Where: q max is the maximum inter-roller pressure per unit width along the roller body; q avg is the average roller pressure per unit width.

[0088] H) Then determine whether the calculation process is not the original support roller profile and whether |f1-f0|<ε. Because the first step of iterative calculation is the original roller profile, the condition is not met, and enter step C) for the next iterative calculation, and let the roller profile curve parameters be the initial roller profile curve parameters. Through iterative calculation, the optimized shoulder cutting length is finally obtained as l L =90mm.

[0089] I) Determine whether the calculation process is the initial shoulder cutting height and whether |f1-f0|<ε. At this time, the shoulder cutting height is the initial shoulder cutting height value, so the condition is not met, and the next iterative calculation is performed in step C), and the shoulder cutting height is increased by one iteration step, that is, 0.05mm, and step H is not performed in the subsequent loop steps). Through iterative calculation, the optimized shoulder cutting height is finally obtained as l H =0.15mm, at this time the optimization function value of the pressure between rollers is reduced from 0.089 of the initial roller shape to 0.036.

[0090] J) Final output shoulder cutting length l L =100mm and shoulder height l H =0.2mm is taken as the final calculation result, and the optimized roller curve is R=[324.85, 324.89, 324.93, 324.95, 324.97, 324.98, 324.99, 325.00, 325.00, 325.00, 325.00, 325.00, 325.00, 325.00, 325.00, 325.00, 325.00, 325.00, 325.00, 325.00, 325.00, 3 25.00, 325.00, 325.00, 325.00, 325.00, 325.00, 325.00, 325.00, 325.00, 325.00, 325.00, 325.00, 325.00, 325.00, 325.00, 324.99, 324.98, 324.97, 324.95, 324.93, 321.89, 324.85] mm; and the roller pressure value P obtained according to the optimized roller profile parameters i=[8.61, 8.68, 8.71, 8.71, 8.69, 8.66, 8.64, 8.57, 8.50, 8.44, 8.39, 8.34, 8.29, 8.25, 8.22, 8.19, 8.16, 8.14, 8.13, 8.12, 8.12, 8.12, 8.13, 8.14, 8.16 , 8.19, 8.22, 8.25, 8.29, 8.34, 8.39, 8.44, 8.50, 8.57, 8.64, 8.66, 8.69, 8.71, 8.71, 8.68, 8.61]t, the calculation curve of the roller fatigue hardening layer depth is h = [0.556, 0.558, 0.559, 0.559, 0. 558, 0.557, 0.557, 0.554, 0.552, 0.550, 0.548, 0.547, 0.545, 0.544, 0.543, 0.542, 0.541, 0.540, 0.540, 0.540, 0.540, 0.540, 0.540, 0.540, 0.541, 0.542, 0.543, 0.544, 0.545, 0.547, 0.548, 0.550, 0.552, 0.554, 0.557, 0.557, 0.558, 0.559, 0.559, 0.558, 0.556] mm, provides guidance for the grinding amount of the backup roller after the roll shape is optimized. The calculation model is as follows:

[0091]

[0092] Where: b is the half width of the contact surface, mm; Z is the depth of the roller fatigue layer, mm; P is the line contact pressure, kg / mm; d w d b are the working roll diameter and the backup roll diameter, mm; E1 and E2 are the elastic moduli of the working roll and the backup roll, respectively.

[0093] The invention controls the roll profile curve of the support roll of the four-high rolling mill, comprehensively considers production parameters such as the diameter of the working roll, the diameter and length of the support roll, the inlet thickness and outlet thickness of the strip, and adjusts the roll profile curve parameters of the support roll to reduce the peak pressure between the rolls during the rolling process and reduce the risk of roll peeling accidents. Figure 6 To optimize the pressure curve between the front rollers, Figure 7 The pressure curve between the rolls is optimized. At the same time, the fatigue layer depth of the roll after roll type optimization is calculated, which provides more reliable guidance for the grinding amount of the support roll, reduces unnecessary losses in grinding, reduces the consumption of the support roll, and thus provides better economic benefits for the production of enterprises. Figure 8 To optimize the rear roll profile, Fig. 9 This is the fatigue hardening layer depth curve of the optimized support roller.

[0094] The above are only preferred embodiments of the present invention. It should be pointed out that, for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as the inventive contents of the present invention.

Claims

1. A method for controlling roll wear by using the roll profile of a four-high rolling mill support roll, characterized in that: It includes the following steps, which are performed by a computer: (A) According to the roll profile curve of the hot rolling four-high mill support roll, the equipment parameters, belt parameters and rolling process parameters of the four-high mill are collected: mainly the radius R of the working roll of the specific stand w , Working roll body length l w , Support roller radius R b , support roller body length l b , strip width B, average strip inlet thickness H, average strip outlet thickness h, rolling pressure P, roller profile power α; (B) Determine the iterative parameters of the calculation process: including the initial shoulder length l L0 , initial shoulder length l H0 , shoulder cutting length iteration step Δ L , shoulder cutting height iteration step length Δ H , and the calculation error ε; (C) calculating the support roller profile curve by using the roller profile parameters to obtain the support roller convexity; (D) dividing the roller body length and the strip width and defining relevant parameters of the calculation process; (E) Calculate the influence function of load and deflection change and the influence function of support force and deflection change; (F) Calculate the roller pressure value of each segment after segmentation; (G) Calculate the optimized function value of the pressure between the rollers. By uniformly distributing the pressure between the rollers, reducing the roller consumption and the peak value of the contact pressure between the rollers, the service life of the support rollers can be increased. The objective function can be expressed as: f1(x)=(q max -q avg ) / q avg Where: q max is the maximum inter-roller pressure per unit width along the roller body; q avg is the average roller pressure per unit width. (H) Determine whether the roll type of the support roll is not the original one and whether |f1-f0|<ε during the calculation process. If it is the original roll type, let l L = l L0 , l H = l H0 , f0=f1, if the calculation error is not satisfied, let l L = l L +Δ L , f0=f1, go to step (C); if all are true, go to step (I); (I) Determine whether the calculation process is the initial shoulder cutting height and whether |f1-f0|<ε. If one of the items is not true, let l H = l H +Δ H , f0=f1, go to step (C), and do not go to step (H) during the cycle; if all are true, go to step (J); (J) Output shoulder length l L and shoulder height l H The final calculation results are used to calculate the roller fatigue hardening layer depth curve based on the inter-roller pressure value obtained according to the optimized roller profile parameters.

2. The method for controlling roll wear by using the roll profile of the backup roll of a four-high rolling mill according to claim 1, characterized in that: The calculation model of the support roller profile curve in step C) is as follows: Where: L b —Length of support roller; R b — Radius of support roller; l L , l H —The length and depth of the shoulder cut of the support roller after roller profile optimization; α—The power of the roller profile curve optimization target.

3. The method for controlling roll wear by using the roll profile of the backup roll of a four-high rolling mill according to claim 1, characterized in that: In step D), the roll length of the support roll and the lateral division of the non-zero rolling pressure portion are divided into 2a+1 segments and 2b+1 segments respectively; let n2=2a+1 and n1=2b+1, which are the total number of lateral segments of the roll length of the support roll and the non-zero rolling pressure portion respectively; among these segments, select two specific segments i,j∈{1,2,...,2a+1} respectively, and the influence function a of the deflection of the working roll and the support roll of the i segment caused by the load of the j segment ij , b ij , the influence function of the left and right support forces on the deflection of the i-th section working roll and support roll The j-th roller pressure value P j , rolling pressure value P' in the jth section j , the total rolling force P for a specific stand.

4. The method for controlling roll wear by using the roll profile of the backup roll of a four-high rolling mill according to claim 1, characterized in that: In step E), the influence function a of the change in the deflection of the i-th section working roll and the support roll caused by the j-th section load is calculated based on the influence function model. ij , b ij , and the influence function of the left and right support forces on the deflection change of the support roller And the calculation model is as follows: Where: k = 10 / 9, 5. The method for controlling roll wear by using the roll profile of the backup roll of a four-high rolling mill according to claim 1, characterized in that: The inter-roller pressure value P of each section is calculated based on the metal plastic deformation model and the roller system elastic deformation model. i , the calculation model is as follows: Where: K is the flexibility coefficient of the working roll and the support roll being pressed against each other, F is the process function, β is the rigid rotation angle of the working roll relative to the support roll, and after solving, β=0, q * is the contact pressure per unit roller length, B is half of the contact width of the two rollers, ν1 and ν2 are the Poisson's ratios on the two cylinders (rollers), and E1 and E2 are the Young's moduli on the two cylinders.

6. The method for controlling roll wear by using the roll profile of the backup roll of a four-high rolling mill according to claim 1, characterized in that: The calculation model of the roller fatigue hardening layer depth curve in step J) is as follows: Where: b is the half width of the contact surface, mm; Z is the depth of the roller fatigue layer, mm; P is the line contact pressure, kg / mm; d w d b are the working roll diameter and the backup roll diameter, mm; E1 and E2 are the elastic moduli of the working roll and the backup roll, respectively.

Images