A comprehensive optimization setting method for the surface roughness of tension rolls suitable for a tandem cold rolling mill

Abstract

The present invention relates to a comprehensive optimization setting method for the surface roughness of tension rolls suitable for a pickling and cold rolling unit. The method comprises the following steps: A) Collect on-site equipment process parameters; B) Define the parameter variable i of the tension roll number and i ≤ m, and the parameter variable j of the micro-arc section number; C) Since it is necessary to calculate the frictional force, the mass of each micro-section is calculated here; D) During the calculation process, the initial values of the roll number and the micro-arc section need to be given to perform the next calculation; E) Initialize the parameter variable j of the micro-arc section number, and make it take values in ascending order from small to large. Here, let j = 1; F) Conduct a force analysis on the 4 rolls of the tension roll group; G) Similarly, the front tension of a certain micro-arc section is equal to the rear tension of the next micro-arc section; H) Next, conduct a force analysis on the strip steel on a certain micro-arc section, including gravity, tension, friction, etc. This solution ensures that no problems such as strip steel scratching and deviation occur during the online period of the tension rolls due to too low roughness.

Description

Technical Field

[0001] The present invention relates to a method, specifically to a comprehensive optimization setting method for the surface roughness of tension rolls suitable for a pickling and cold rolling mill unit, belonging to the technical field of cold rolling. Background Art

[0002] The tension roll group, also known as the tensioning roll group, is widely used in the continuous production line of strip steel. The function of the tension roll is to achieve the separation and adjustment of tension in the continuous production line of strip steel. For a pickling and cold rolling mill unit, the tension rolls are generally located before and after the loop. The arrangement of the tension rolls enables the strip steel to form an approximately 220° wrap angle on the surface of each tension roll. Such a design ensures the tension establishment of the strip steel in the pickling and cold rolling mill unit, greatly improving the phenomena such as strip deviation caused by slipping, which are harmful to the production of the unit, and is of great significance for improving the stable rolling of the pickling and cold rolling mill unit.

[0003] Through long-term on-site tracking, it is found that the surface roughness of the tension roll gradually decreases as the rolling kilometers increase. When the roughness of the tension roll is less than a certain value, it will cause the slipping phenomenon of the strip steel at this position, resulting in the strip deviation problem. Moreover, the slipping at the tension roll position will also cause fluctuations in the tension torque, thereby affecting the tension during the operation of the strip steel, and further affecting the centering effect of the strip steel of the unit. Therefore, the size of the surface roughness of the tension roll has an important impact on the surface quality of the strip steel and the tension layout, and has important research value for the influence on strip deviation. Moreover, it will also have a great impact on the stability of the entire unit, and serious consequences such as strip breakage may occur, causing huge economic losses.

[0004] Liu Canhong et al. improved the slipping phenomenon of the tension roll by adjusting the tension and the surface roughness of the tension roll (Patent No.: CN201911346564.X), and Wang Ye et al. controlled the slipping of the tension roll by controlling the rolling fluid parameters and improving the roll surface to increase the friction coefficient (Patent No.: CN201910704267.1). However, neither of the two authors involved the calculation and determination of the original roughness value of the tension roll in the article, and only gave a range value. Therefore, to ensure that the roughness of the tension roll does not become too small during the online stage, the present invention gives a method for determining the original roughness of the tension roll according to the roughness attenuation principle, so that under this roughness, when the rolling kilometers are certain, the roughness attenuation will not be too large to affect the production of the unit. Therefore, establishing a comprehensive optimization setting method for the surface roughness of the tension roll suitable for a pickling and cold rolling mill unit becomes the key to solving on-site problems. Summary of the Invention

[0005] The present invention precisely aims at the problems existing in the prior art and provides a comprehensive optimization setting method for the surface roughness of tension rolls suitable for a pickling and cold rolling unit. This technical solution addresses the problem of strip deviation caused by the reduction of the surface roughness of tension rolls in the pickling and cold rolling unit. Combining production equipment and actual on-site production, etc., within the reasonable range of ensuring the surface roughness of the tension rolls, the force analysis of the tension rolls is carried out, and the roughness attenuation model is used to optimize the roll installation time and the original roughness of the rolls, ensuring that no strip scratching and deviation problems occur due to too low roughness during the online period of the tension rolls.

[0006] To achieve the above object, the technical solution of the present invention is as follows. A comprehensive optimization setting method for the surface roughness of tension rolls suitable for a pickling and cold rolling unit, the method comprising the following steps:

[0007] A) Collect on-site equipment process parameters, the front tension F of the tension roll group q , the rear tension F of the tension roll group h , the wrap angle α of the tension roll, the tension loss F caused by the elastic-plastic bending of the strip s , the number m of tension rolls in the tension roll group, the strip speed v, the strip density ρ, the strip width B, the strip thickness h, the tension roll diameter d, and the radius r;

[0008] B) Define the tension roll number parameter variable i and i ≤ m, the micro-arc segment number parameter variable j, and j ≤ n, as Figure 1 shown, the minimum friction coefficient parameter variable μ, and initialize μ = 1;

[0009] C) Since the calculation of friction force is required, the mass of each micro-segment is calculated here: According to the roll body length and considering the calculation amount problem, the differential precision n = 100 is taken here, and the angle θ between the gravity direction of each micro-segment and the micro-segment normal direction is collected ij , and the mass of each micro-segment is calculated

[0010] D) During the calculation process, the initial values of the roll number and the micro-arc segment need to be given for the next calculation, so the tension roll number parameter variable i is initialized here, and it takes values in ascending order from small to large. Here, let i = 1;

[0011] E) Initialize the micro-arc segment number parameter variable j, and it takes values in ascending order from small to large. Here, let j = 1;

[0012] F) Conduct a force analysis on the 4 rolls of the tension roll group. The front tension of the first roll is equal to the rear tension of the second roll, so the front tension F of the i-th roll can be calculated qi , and the rear tension F hi , where

[0013] G) Similarly, the front tension of a certain micro-arc segment is equal to the rear tension of the next micro-arc segment. Therefore, the front tension F of the j-th micro-arc segment on the i-th roller can be calculated. qij and the rear tension F hij , where

[0014] H) Next, perform a force analysis on the strip steel on a certain micro-arc segment, including gravity, tension, and friction. The frictional force F on the j-th micro-arc segment on the i-th roller can be calculated. fij , where l is a coefficient considering the movement direction of the strip steel, and δ is the angle between the movement direction of the strip steel and the direction of gravity;

[0015] I) Based on the previous step, the normal pressure F on the j-th micro-arc segment on the i-th roller can be calculated. Nij ,

[0016] J) Calculate the necessary friction coefficient μ of the j-th micro-arc segment on the i-th roller. ij , where λ is a coefficient considering the influence of on-site tension fluctuations on strip steel slipping, obtained by collecting historical data and performing regression processing. Each unit has its own influence coefficient. Here, for this unit, λ = 1.0 - 1.3 is taken;

[0017] K) Determine whether the inequality μ - μ ij ≥0 holds. If it holds, let μ = μ ij and go to step (l). If it does not hold, directly go to step (l);

[0018] L) Determine whether the inequality j < n holds. If it holds, let j = j + 1 and go to step (g). If it does not hold, go to step (m);

[0019] M) Determine whether the inequality i < m holds. If it holds, let i = i + 1 and go to step (e). If it does not hold, go to step (n);

[0020] N) Calculate the limit value ε of the roughness of the tension roller. min , ε min = aμ b + c. Through multiple on-site tests and combined with data statistical analysis, the values of the coefficients a, b, and c in the calculation formula can be obtained;

[0021] O) Calculate the necessary roughness ε of the tension roller. z , ε z = ε min + ε y , where ε ySet a margin for the minimum roughness, which is determined by the on-site situation and generally takes ε y = 0.1 - 0.2 μm;

[0022] P) Calculate the target value of the roughness of the grinding roll, where B l is the roughness attenuation coefficient of the tension roll, which is determined by the material of the tension roll and the production situation. A large amount of on-site data can be collected, and the roughness attenuation coefficient of the current unit can be obtained through regression processing. Here, take B l = 1.3×10 -4 ~1.5×10 -4 , and L is the length of the strip steel within the roll change cycle;

[0023] Q) During the roll change cycle, grind the roll with ε 0 as the roughness target value, which can ensure that the roughness of the tension roll is always within a reasonable value.

[0024] Compared with the prior art, the present invention has the following advantages. This technical solution can achieve the design criterion of the original roughness of the tension roll, maintain the surface roughness of the roll within the normal working range during the roll change cycle, and minimize the strip steel deviation problem caused by too small roughness. During the experimental stage, the deviation amount of the strip steel at the tension roll decreased significantly within half a year. The statistical data is shown in Table 1. It can be seen that this technology has obvious effects on controlling the strip steel deviation and strip steel scratching at the tension roll, providing better technical guarantee for the stable rolling of the unit.

[0025] Table 1 Statistical data of strip steel deviation at the tension roll within half a year

[0026] Brief description of the drawings

[0027] Figure 1 is a schematic diagram of the tension roll group described in the present invention;

[0028] Figure 2 is the overall flowchart of a comprehensive optimization setting method for the surface roughness of the tension roll suitable for the acid rolling unit of the present invention; Detailed implementation manners

[0029] To deepen the understanding of the present invention, the following detailed description is made in conjunction with the drawings for this embodiment.

[0030] Example 1: Refer to Figure 1 , a comprehensive optimization setting method for the surface roughness of the tension roll suitable for the acid rolling unit, the method includes the following steps:

[0031] A) Collect on-site equipment process parameters, the front tension F q of the tension roll group, and the rear tension F h, the wrap angle α of the tension roll, and the tension loss F caused by the elastic-plastic bending of the strip steel s , the number m of tension rolls in the tension roll group, the strip steel speed v, the strip steel density ρ, the strip steel width B, the strip steel thickness h, the tension roll diameter d, and the radius r;

[0032] B) Define the parameter variable i of the tension roll number and i ≤ m, and the parameter variable j of the micro-arc segment number, and j ≤ n, as Figure 1 shown, the parameter variable μ of the minimum friction coefficient, and initialize μ = 1;

[0033] C) Since it is necessary to calculate the frictional force, the mass of each micro-segment is calculated here: According to the roll body length and considering the calculation amount problem, the differential precision n = 100 is taken here, and the angle θ between the gravity direction of each micro-segment and the micro-segment normal direction is collected ij , calculate the mass of each micro-segment

[0034] D) During the calculation process, it is necessary to give the initial values of the roll number and the micro-arc segment for the next calculation, so the parameter variable i of the tension roll number is initialized here, and it takes values in ascending order. Here, let i = 1;

[0035] E) Initialize the parameter variable j of the micro-arc segment number, and it takes values in ascending order. Here, let j = 1;

[0036] F) Conduct a force analysis on the 4 rolls of the tension roll group. The front tension of the first roll is equal to the rear tension of the second roll, so the front tension F of the i-th roll can be calculated qi , the rear tension F hi , where

[0037] G) Similarly, the front tension of a certain micro-arc segment is equal to the rear tension of the next micro-arc segment. Therefore, the front tension F of the j-th micro-arc segment on the i-th roll can be calculated qij , the rear tension F hij , where

[0038] H) Next, conduct a force analysis on the strip steel on a certain micro-arc segment, including gravity, tension, and frictional force. The frictional force F received by the j-th micro-arc segment on the i-th roll can be calculated fij , In the formula, l is the coefficient considering the strip steel movement direction, and δ is the angle between the strip steel movement direction and the gravity direction;

[0039] I) Based on the previous step, the normal pressure F received by the j-th micro-arc segment on the i-th roll can be calculated Nij ,

[0040] J) Calculate the necessary friction coefficient μ of the j-th micro-arc segment on the i-th roller ij , where λ is the influence coefficient considering the influence of on-site tension fluctuation on strip slippage, which is obtained by collecting historical data and performing regression processing. Each unit has its own influence coefficient. Here, for this unit, λ = 1.0 - 1.3;

[0041] K) Judge whether the formula μ - μ ij ≥0 holds. If it holds, let μ = μ ij and transfer to step (l). If it does not hold, directly transfer to step (l);

[0042] L) Judge whether the formula j < n holds. If it holds, let j = j + 1 and transfer to step (g). If it does not hold, transfer to step (m);

[0043] M) Judge whether the formula i < m holds. If it holds, let i = i + 1 and transfer to step (e). If it does not hold, transfer to step (n);

[0044] N) Calculate the limit value ε of the roughness of the tension roller min , ε min = aμ b + c. Through multiple on-site tests and combined with data statistical analysis, the values of the coefficients a, b, and c in the calculation formula can be obtained;

[0045] O) Calculate the necessary roughness ε of the tension roller z , ε z = ε min + ε y , where ε y is the minimum roughness setting margin, which is determined by the on-site situation. Generally, ε y = 0.1 - 0.2 μm;

[0046] P) Calculate the grinding roll target value of the roughness, where B l is the roughness attenuation coefficient of the tension roller, which is determined by the material of the tension roller and the production situation. A large amount of on-site data can be collected, and the roughness attenuation coefficient of the current unit can be obtained by regression processing. Here, B l = 1.3×10 -4 ~1.5×10 -4 , and L is the length of the strip within the roll change cycle;

[0047] Q) During the roll change cycle, grind the roll with ε 0 as the roughness target value, and the roughness of the tension roller can always be ensured to be a reasonable value.

[0048] Specific Embodiment 1: A comprehensive optimization setting method for the surface roughness of a tension roll suitable for an acid rolling mill unit, the method comprising the following steps:

[0049] A) Collect on-site parameters, the front tension F of the tension roll group q = 58 KN, the rear tension F of the tension roll group h = 53 KN, the wrap angle α of the tension roll = 200°, the tension loss F caused by the elastic-plastic bending of the strip s = 50 N, the number m of tension rolls in the tension roll group = 4, the strip speed v = 4 m / s, the strip density ρ = 7850 kg / m 3 , the strip width B = 1000 mm, the strip thickness h = 3 mm, the diameter d of the tension roll = 1200 mm, the radius r = 600 mm; The tension roll arrangement is as Figure 1 shown;

[0050] B) Define the tension roll number parameter variable i, and i ≤ 4, the micro-arc segment number parameter variable j, and j ≤ n, as Figure 1 shown, the minimum friction coefficient parameter variable μ, and initialize μ = 1;

[0051] C) Since it is necessary to calculate the frictional force, the mass of each micro-segment is calculated here: Considering the calculation amount according to the roll body length, the differential precision n = 100 is taken here, and the angle θ between the gravity direction of the first micro-arc segment and the micro-segment normal direction is collected 11 = 180°, and the mass of the first micro-arc segment is calculated

[0052] D) During the calculation process, it is necessary to give the initial values of the roll number and the micro-arc segment for the next calculation, so the tension roll number parameter variable i is initialized here, and it takes values in ascending order from small to large. Here, i = 1 is set;

[0053] E) Initialize the micro-arc segment number parameter variable j, and it takes values in ascending order from small to large. Here, j = 1 is set;

[0054] F) Analyze the forces on the 4 rolls of the tension roll group. The front tension of the first roll is equal to the rear tension of the second roll, so the front tension F of the first roll can be calculated q1 = 54.2 KN, the rear tension F h1 = 53 KN;

[0055] G) Similarly, the front tension of a certain micro-arc segment is equal to the rear tension of the next micro-arc segment. Therefore, the front tension F of the first micro-arc segment on the first roll can be calculated q11 = 54 KN, the rear tension F h11 = 53 KN;

[0056] H) Next, perform a force analysis on the strip steel in a certain micro-arc section, including gravity, tension, and friction, and calculate the friction force F on the first micro-arc section of the first roller. f11 = 73.95 N, where l is the coefficient considering the strip steel movement direction, and here l = 1;

[0057] I) Based on the previous step, the normal pressure F on the first micro-arc section of the first roller can be calculated. N11 = 986 N;

[0058] J) Calculate the necessary friction coefficient μ of the first micro-arc section of the first roller. 11 , and by collecting historical data and performing regression processing, the influence coefficient of the tension fluctuation of the unit on strip steel slipping is taken as λ = 1.0.

[0059] Through the loop calculation from step K) to step M), the result of step N) is obtained;

[0060] N) Calculate the roughness limit value ε. min , and through experiments, the fitting coefficients a = 0.65, b = 0.3, c = 0.37 are obtained, so as to obtain ε. min = aμ b + c = 0.65 × 0.095 0.3 + 0.37 = 0.69 (μm);

[0061] O) Calculate the allowable minimum roughness ε. z , according to the on-site situation, here the roughness setting margin ε y = 0.28 μm, ε z = ε min + ε y = 0.69 + 0.28 = 0.97 (μm);

[0062] P) Calculate the target value of the roughness of the grinding roll. First, collect a large amount of on-site production data, and through regression processing, obtain the roughness attenuation coefficient B of the current unit. l = 1.×8 -5 , L = 1×10 5 km.

[0063] Q) Therefore, under the working conditions described in the embodiment, when the rolling kilometer number is 1×10 5 km, the original roughness of the surface of the tension roll is required to be designed as 6.2 μm.

[0064] Specific Embodiment 2: A comprehensive optimization setting method for the surface roughness of the tension roll suitable for the acid rolling unit, the method includes the following steps:

[0065] A) Collect on-site parameters, the front tension F of the tension roll group q = 57 KN, the rear tension F of the tension roll group h = 52 KN, the wrap angle α of the tension roll is 200°, the tension loss F caused by the elastic-plastic bending of the strip s = 50 N, the number m of tension rolls in the tension roll group is 4, the strip speed v = 4.2 m / s, the strip density ρ = 7850 kg / m 3 , the strip width B = 950 mm, the strip thickness h = 2.5 mm, the diameter d of the tension roll is 1200 mm, the radius r = 600 mm; the layout of the tension rolls is as Figure 1 shown;

[0066] B) Define the parameter variable i of the tension roll number, and i ≤ 4, the parameter variable j of the micro-arc segment number, and j ≤ n, as Figure 1 shown, the parameter variable μ of the minimum friction coefficient, and initialize μ = 1;

[0067] C) Since it is necessary to calculate the frictional force, the mass of each micro-segment is calculated here: According to the roll body length and considering the calculation amount problem, the differential precision n = 100 is taken here, and the angle θ between the gravity direction and the micro-segment normal direction of the first micro-arc segment is collected 11 = 180°, and the mass of the first micro-arc segment is calculated

[0068] D) In the calculation process, it is necessary to give the initial values of the roll number and the micro-arc segment for the next calculation, so the parameter variable i of the tension roll number is initialized here, and it takes values in ascending order from small to large. Here, let i = 1;

[0069] E) Initialize the parameter variable j of the micro-arc segment number, and it takes values in ascending order from small to large. Here, let j = 1;

[0070] F) Conduct a force analysis on the 4 rollers of the tension roll group. The front tension of the first roller is equal to the rear tension of the second roller, so the front tension F of the first roller can be calculated q1 = 53.5 KN, the rear tension F h1 = 52 KN;

[0071] G) Similarly, the front tension of a certain micro-arc segment is equal to the rear tension of the next micro-arc segment. Therefore, the front tension F of the first micro-arc segment on the first roller can be calculated q11 = 53 KN, the rear tension F h11 = 52 KN;

[0072] H) Next, conduct a force analysis on the strip on a certain micro-arc segment, including gravity, tension, and frictional force. The frictional force F received by the first micro-arc segment on the first roller can be calculated f11= 54.69 N, where l is the coefficient considering the strip movement direction, and here l = 1;

[0073] I) Based on the previous step, the normal pressure F on the first micro-arc segment of the first roller can be calculated N11 = 875 N;

[0074] J) Calculate the necessary friction coefficient μ of the first micro-arc segment on the first roller 11 , and by collecting historical data and performing regression processing, the influence coefficient of the tension fluctuation of this unit on strip slippage is taken as λ = 1.2,

[0075] Through the loop calculation from step K) to step M), the result of step N) is obtained;

[0076] N) Calculate the roughness limit value ε min , and through experiments, the fitting coefficients a = 0.65, b = 0.3, c = 0.2 are obtained, and ε min = aμ b + c = 0.65 × 0.095 0.3 + 0.27 = 0.59 (μm);

[0077] O) Calculate the allowable minimum roughness ε z , and according to the on-site situation, the roughness setting margin ε y = 0.12 μm is taken here, ε z = ε min + ε y = 0.59 + 0.12 = 0.71 (μm);

[0078] P) Calculate the target value of the roughness of the grinding roll. First, collect a large amount of on-site production data, and through regression processing, the roughness attenuation coefficient B of the current unit is obtained l = 1.×8 -5 , L = 1.2 × 10 5 km,

[0079] Q) Therefore, under the working conditions described in the embodiment, when the rolling kilometer number is 1 × 10 5 km, the original roughness of the surface of the tension roll is required to be designed as 6.5 μm.

[0080] From the above two specific embodiments, it can be seen that from the known on-site data, the set value of the original roughness of the surface of the tension roll under the target rolling kilometer number can be calculated to guide on-site production. The data of the optimized tension roll in Table 1 is the original roughness in Embodiment 1. Through the actual inspection of on-site production, it can be clearly seen that the roughness of the optimized tension roll ensures the safe and stable production of the unit.

[0081] It should be noted that the above embodiments are not intended to limit the protection scope of the present invention, and equivalent transformations or substitutions made on the basis of the above technical solutions all fall within the protection scope of the claims of the present invention.

Claims

1. A comprehensive optimization setting method for the surface roughness of tension rolls suitable for a pickling and cold rolling mill unit, characterized in that, the method comprises the following steps: A) Collect on-site equipment process parameters, B) Define the tension roll number parameter variable i and i ≤ m, the micro-arc section number parameter variable j, and j ≤ n, and the minimum friction coefficient parameter variable μ, and initialize μ = 1; C) Since it is necessary to calculate the frictional force, the mass of each micro-section is calculated here; D) During the calculation process, the initial values of the roll number and the micro-arc section need to be given for the next calculation, so the tension roll number parameter variable i is initialized here to take values in ascending order, and here i = 1 is set; E) Initialize the micro-arc section number parameter variable j to take values in ascending order, and here j = 1 is set; F) Analyze the forces on the 4 rolls of the tension roll group, G) Similarly, the front tension of a certain micro-arc section is equal to the rear tension of the next micro-arc section, H) Next, analyze the forces on the strip steel on a certain micro-arc section, including gravity, tension, and friction, I) Based on the previous step, calculate the normal pressure F exerted on the j-th micro-arc segment of the i-th roller Nij , J) Calculate the necessary friction coefficient μ for the j-th micro-arc segment on the i-th roller ij , K) Determine if the expression μ - μ ij ≥ 0 holds. If it holds, let μ = μ ij and proceed to step (l). If it does not hold, directly proceed to step (l); L) Judge whether the formula j < n holds. If it holds, set j = j + 1 and transfer to step (g). If it does not hold, transfer to step (m); M) Judge whether the formula i < m holds. If it holds, set i = i + 1 and transfer to step (e). If it does not hold, transfer to step (n); N) Calculate the limit value ε of the roughness of the tension roller min , ε min = aμ b + c. Through multiple on-site tests and combined with data statistical analysis, the values of the coefficients a, b, and c in the calculation formula can be obtained; O) Calculate the necessary roughness ε of the tension roller z , ε z = ε min + ε y , where ε y is the minimum roughness setting margin, determined by the on-site situation, and take ε y = 0.1 - 0.2 μm; P) Calculate the target value of the roughness of the grinding roll, where B l is the roughness attenuation coefficient of the tension roll, which is determined by the material and production conditions of the tension roll. A large amount of on-site data is collected, and the roughness attenuation coefficient of the current unit is obtained by regression processing. Here, take B l = 1.3×10 -4 ~ 1.5×10 -4 , and L is the length of the strip steel within the roll change cycle; Q) During the roll change cycle, grinding the rolls with ε 0 as the roughness target value can ensure that the roughness of the tension roll is always a reasonable value.

2. The comprehensive optimization setting method for the surface roughness of tension rolls suitable for a pickling and cold rolling mill unit according to claim 1, characterized in that, Step A) Collect the process parameters of on-site equipment, the front tension F of the tension roll group q , the rear tension F of the tension roll group h , the wrap angle α of the tension roll, the tension loss F caused by the elastic-plastic bending of the strip s , the number m of tension rolls in the tension roll group, the strip speed v, the strip density ρ, the strip width B, the strip thickness h, the tension roll diameter d.

3. The comprehensive optimization setting method for the surface roughness of tension rolls suitable for a pickling and cold rolling mill unit according to claim 2, characterized in that, Step C) Since it is necessary to calculate the frictional force, the mass of each micro-segment is calculated here: Considering the roll body length and the calculation amount, the differential precision n = 100 is taken here, and the angle θ between the gravity direction of each micro-segment and the normal direction of the micro-segment is collected ij , and the mass ΔM of each micro-segment is calculated:

4. The comprehensive optimization setting method for the surface roughness of tension rolls suitable for a pickling and cold rolling mill unit according to claim 3, characterized in that, Step F) Analyze the forces on the four rollers of the tension roller group. The front tension of the first roller is equal to the rear tension of the second roller, so the front tension Fi of the i-th roller can be calculated qi , and the rear tension Fi hi , where 5. The comprehensive optimization setting method for the surface roughness of tension rolls suitable for a pickling and cold rolling mill unit according to claim 4, characterized in that, Step G) Similarly, the front tension of a certain micro-arc segment is equal to the rear tension of the next micro-arc segment. Therefore, the front tension F qij , and the rear tension F hij can be calculated, where 6. The comprehensive optimization setting method for the surface roughness of tension rolls suitable for a pickling and cold rolling mill unit according to claim 5, characterized in that, Step H) Next, perform a force analysis on the strip steel in a certain micro-arc segment, including gravity, tension, and friction, and calculate the frictional force F on the j-th micro-arc segment of the i-th roller. fij , where l is a coefficient considering the movement direction of the strip steel, and δ is the angle between the movement direction of the strip steel and the direction of gravity.

7. The comprehensive optimization setting method for the surface roughness of tension rolls suitable for a pickling and cold rolling mill unit according to claim 6, characterized in that, Step J) Calculate the necessary friction coefficient μ of the j-th micro-arc segment on the i-th roller ij , where λ is the influence coefficient considering the effect of on-site tension fluctuations on strip slippage, obtained by collecting historical data and performing regression processing. Each unit has its own influence coefficient, and here λ = 1.0 - 1.3 is taken for this unit.

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