A seamless steel pipe piercing wall thickness precision control method based on uneven deformation coefficient

Abstract

The application provides a seamless steel pipe piercing wall thickness precision control method based on a deformation uneven coefficient, and relates to the field of rolling automation control technology. The method first acquires the temperature, contact pressure, metal flow speed and guiding constraint parameters of the symmetric positions of a piercing deformation zone, and establishes a deformation uneven coefficient representing the deformation coordination degree of the piercing zone; then a quantitative relationship between the deformation uneven coefficient and the raw pipe wall thickness deviation is constructed, and a corresponding target control range is determined according to the target wall thickness precision requirement; when the actual deformation uneven degree exceeds the target range, the roll gap, guide plate gap and top extension are taken as the regulation and control parameters for correction, so as to reduce the deformation uneven degree of the piercing zone and improve the raw pipe wall thickness uniformity. The method is based on the actual adjustable process parameters in the piercing process, and can provide a method support for the stable control of the wall thickness precision of the seamless steel pipe piercing process.

Description

Technical Field

[0001] This invention relates to the field of automated rolling control technology, and in particular to a method for controlling the accuracy of piercing wall thickness of seamless steel pipes based on the deformation non-uniformity coefficient. Background Technology

[0002] Piercing seamless steel tubes is a crucial first hot deformation process that transforms solid round billets into hollow tubes. This process involves the combined action of rolls, guide plates, and mandrels, characterized by high temperature, large deformation, and multi-field coupling. The accuracy of the tube wall thickness during piercing directly affects the stability of subsequent rolling, the consistency of finished product dimensions, and material utilization. In current production, tube wall thickness deviations are usually closely related to uneven metal deformation in the piercing zone. Specifically, this manifests as differences in deformation resistance caused by uneven temperature distribution across the billet cross-section, stress imbalance caused by asymmetrical stress distribution between the rolls and the billet, and incoordination between lateral expansion and axial extension of the metal due to changes in the constraint state of the guide plates and the position of the mandrel.

[0003] Currently, the adjustment of capillary tube wall thickness deviation in the field is mainly corrected through process parameters such as roller gap, guide plate distance, and top extension. However, it is still mainly based on experience and lacks a unified physical criterion that can comprehensively characterize the uneven temperature, uneven stress, uneven flow, and uneven guiding constraints in the piercing zone. Furthermore, there is a lack of a control method to establish a quantitative relationship between this criterion and the wall thickness deviation and adjustable parameters in the field. In particular, the existing technology largely remains at the qualitative level regarding the combined effect of guide plate distance, local guide gap, and contact state on guiding constraints, making it difficult to incorporate into a unified wall thickness control model. Therefore, it is necessary to propose a mechanism-based formula-based method for controlling the piercing wall thickness accuracy of seamless steel tubes to achieve stable control of capillary tube wall thickness accuracy. Summary of the Invention

[0004] To address the issues in existing technologies regarding capillary tube wall thickness deviations caused by inconsistent metal deformation, uneven stress distribution, and differences in guiding constraints during the piercing process, and the fact that current seamless steel tube piercing wall thickness control primarily relies on empirical adjustments and lacks unified mechanistic criteria and quantitative correction methods, this invention provides a method for controlling the accuracy of seamless steel tube piercing wall thickness based on the deformation unevenness coefficient. The technical solution is as follows: A method for controlling the accuracy of perforated wall thickness in seamless steel pipes based on the deformation non-uniformity coefficient, characterized in that the method includes: S1. Obtain relevant data on the production process of the perforation deformation zone; S2. Construct the perforation deformation non-uniformity coefficient based on the data obtained in S1. K u ; S3. Define the capillary wall thickness deviation coefficient and establish the relationship between the wall thickness deviation coefficient and the deformation unevenness coefficient; S4. Based on the allowable wall thickness deviation of the target product, determine the target deformation non-uniformity coefficient. At the same time, compare the deformation non-uniformity coefficient constructed in S2 with the target deformation non-uniformity coefficient. If the deformation non-uniformity coefficient in S2 is not greater than the target deformation non-uniformity coefficient, output the final optimized process parameters; otherwise, continue to execute S5 and S6. S5. Using the roller gap, guide plate gap and top extension as control quantities, the uneven state of perforation deformation is corrected. The uneven force component, the uneven guide constraint component and the uneven flow component are defined. The process parameters are corrected according to the deviation between each component and the target component. S6. Based on the corrected process parameters obtained in S6, roll again and repeat the contents of steps S1 to S6.

[0005] The relevant data for the perforation deformation zone production process in S1 includes the current maximum wall thickness of the capillary tube. S max Minimum wall thickness S min The current roller spacing used for perforation E 0. Guide plate distance A 0. Top extension L 0; The temperature of the perforated deformation zone at the symmetrical position of the contact area between the left and right guide plates and the capillary tube, obtained by on-site measurement. T 1. T 2; The contact pressure at the symmetrical position of the contact area between the upper and lower rolls and the tube obtained by on-site measurement. p 1. p 2; The metal flow velocity at the symmetrical position of the contact area between the left and right guide plates and the capillary tube, obtained through on-site measurement. v 1. v 2; Diameter of the guide zone top D Lateral offset of the capillary center relative to the guide center y ;No. i Actual contact length between the side guide plate and the capillary tube ;No. i Side average contact pressure Reference contact length Reference contact pressure And the equivalent guiding constraint at the symmetrical positions of the left and right guide plates. g 1. g 2.

[0006] The equivalent guiding constraint g 1. g 2. The calculation method is as follows:

[0007]

[0008] in,A The guide plate distance; l 1. l 1 is a correction factor, obtained by fitting actual production data from the field; e To avoid small positive numbers with a denominator of zero, the value takes any value between [0,1] when the denominator is not zero, and takes 1 when the denominator is zero.

[0009] The perforation deformation non-uniformity coefficient in S2 K u The construction process is as follows: S21. Calculate the average value of the data:

[0010]

[0011]

[0012]

[0013] in, The average temperature of the left and right guide plates in the perforated deformation zone. Temperature of the left guide plate in the perforated deformation zone. The temperature of the right guide plate is located symmetrically to the left guide plate in the perforation deformation zone. This represents the average contact pressure between the upper and lower rolls. The contact pressure of the upper roll. To achieve the contact pressure of the lower roll, which is symmetrical to the upper roll, This represents the average metal flow velocity of the left and right guide plates. The metal flow velocity of the left guide plate. The metal flow velocity of the right guide plate, which is symmetrical to the left guide plate. The average value of the equivalent guiding constraint quantity. , This represents the equivalent constraint quantity at the symmetrical positions of the left and right guide plates; S22. Calculate the unevenness difference:

[0014]

[0015]

[0016]

[0017] in, The difference in temperature between the left and right guide plates at symmetrical positions in the perforated deformation zone. This represents the difference in contact pressure between the symmetrical positions of the upper and lower rolls. This represents the difference in metal flow velocity at symmetrical positions on the left and right guide plates. The difference in equivalent guiding constraint amount between the symmetrical positions of the left and right guide plates; S23, Constructing the coefficient of non-uniform perforation deformation K u :

[0018] in: a , b , c , d Let the weighting coefficients satisfy: .

[0019] The coefficient of deformation non-uniformity K u Used to characterize the degree of inconsistency between the temperature field, force field, flow field, and guiding constraint state during the perforation process; K u The larger the value, the more severe the uneven deformation in the perforated area.

[0020] The capillary wall thickness deviation coefficient in S3 for:

[0021] in: S max This represents the maximum wall thickness of the capillary tube. S min This is the minimum wall thickness of the capillary tube.

[0022] The relationship between the wall thickness deviation coefficient and the deformation unevenness coefficient in S3 is as follows:

[0023] in: C u The wall thickness response coefficient is obtained by calibrating on-site production data to ensure consistent wall thickness deviation caused by the same degree of deformation unevenness under the same specifications.

[0024] The target deformation non-uniformity coefficient in S4 for:

[0025] in, d lim The allowable wall thickness deviation for the current target product. C u is the wall thickness response coefficient.

[0026] In step S4, if the deformation non-uniformity coefficient in S2 is less than the target deformation non-uniformity coefficient, then the current process parameters are directly output as the final optimized process parameters. These process parameters include the roll gap. E fina guide plate distance A fina and top extension L fina .

[0027] The uneven force component in S5 K P Uneven component of guidance constraints K G and flow non-uniformity components K V Specifically:

[0028] in, This represents the difference in contact pressure between the symmetrical positions of the upper and lower rolls. This represents the difference in metal flow velocity at symmetrical positions on the left and right guide plates. The difference in equivalent guiding constraint amount between the symmetrical positions of the left and right guide plates is the value of the unevenness. b , c , d These are the weighting coefficients; The target component in S5 is specifically:

[0029] in, , , These are the target components of the force non-uniformity component, the guiding constraint non-uniformity component, and the flow non-uniformity component, respectively. a , b , c , d The weighting coefficients are determined by fitting different parameters and corresponding wall thickness data from actual on-site production. The difference in temperature between the left and right guide plates at symmetrical positions in the perforated deformation zone. The average temperature of the left and right guide plates in the perforated deformation zone. This represents the temperature non-uniformity component. The process parameters in S5 include the roller spacing. E guide plate distance A and top extension L， The specific revisions are as follows:

[0030] in, , , These are the corrected roller gap, guide plate distance, and top extension, respectively. , , These are the roller spacing, guide plate spacing, and top extension amount used for the previous steel pipe, respectively. k E , k A , k L The correction factor was determined based on the actual production conditions on site. i This is the serial number of the steel pipe.

[0031] The temperature at the symmetrical positions of the left and right guide plates in the perforation deformation zone, the contact pressure at the symmetrical positions of the upper and lower rolls, the metal flow velocity at the symmetrical positions of the left and right guide plates, the capillary wall thickness, and the mandrel diameter are measured by online detection devices to ensure the timeliness, accuracy, and stability of the collected data. Specifically, the temperature data is obtained by infrared thermometers installed at the symmetrical positions of the guide plates, the contact pressure data is obtained by the upper and lower mill force detection devices and the pressing force detection devices, the metal flow velocity is obtained by online speed measuring devices installed at the symmetrical positions of the guide plates, the capillary wall thickness data is obtained by online thickness measuring devices, and the mandrel diameter data is obtained by infrared diameter measuring devices.

[0032] The preferred detection accuracy of the online detection device is as follows: the capillary wall thickness detection deviation is controlled within ±1mm, the capillary outer diameter detection deviation is controlled within ±2mm, the temperature detection deviation is controlled within ±50℃, the contact pressure detection deviation is controlled within ±1%, and the speed detection deviation is controlled within ±1%.

[0033] The beneficial effects of the technical solutions provided in the embodiments of the present invention include at least the following: The above solution can effectively control the accuracy of the tube wall thickness during the piercing process of seamless steel tubes, reduce wall thickness deviation, improve the uniformity of tube wall thickness and dimensional consistency, thereby improving the stability of the piercing process and product quality. Attached Figure Description

[0034] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0035] Figure 1 This is a flowchart of a method for controlling the perforation wall thickness accuracy of seamless steel pipe based on the deformation non-uniformity coefficient, provided by an embodiment of the present invention. Figure 2 This is a comparison chart of wall thickness control using manual setting and the control method of the present invention for a certain specification provided in an embodiment of the present invention. Detailed Implementation

[0036] The technical solution of the present invention will now be described with reference to the accompanying drawings.

[0037] In embodiments of the present invention, words such as "exemplarily," "for example," etc., are used to indicate that something is an example, illustration, or description. Any embodiment or design described as "exemplary" in the present invention should not be construed as being more preferred or advantageous than other embodiments or designs. Specifically, the use of the word "exemplary" is intended to present the concept in a concrete manner. Furthermore, in embodiments of the present invention, the meaning expressed by "and / or" can be both, or either one.

[0038] In this embodiment of the invention, sometimes a subscript such as W1 may be written in a non-subscript form such as W1. When the difference is not emphasized, the meaning they express is the same.

[0039] To make the technical problems, technical solutions and advantages of the present invention clearer, a detailed description will be given below in conjunction with the accompanying drawings and specific embodiments.

[0040] This invention provides a method for controlling the accuracy of perforated wall thickness in seamless steel pipes based on the deformation non-uniformity coefficient. For example... Figure 1 The flowchart shown is a method for controlling the wall thickness accuracy of seamless steel pipes through perforation based on the deformation non-uniformity coefficient. This method may include the following steps: S1. Obtain relevant data on the production process of the perforation deformation zone; S2. Construct the perforation deformation non-uniformity coefficient based on the data obtained in S1. K u ; S3. Define the capillary wall thickness deviation coefficient and establish the relationship between the wall thickness deviation coefficient and the deformation unevenness coefficient; S4. Based on the allowable wall thickness deviation of the target product, determine the target deformation non-uniformity coefficient. At the same time, compare the deformation non-uniformity coefficient constructed in S2 with the target deformation non-uniformity coefficient. If the deformation non-uniformity coefficient in S2 is not greater than the target deformation non-uniformity coefficient, output the final optimized process parameters; otherwise, continue to execute S5 and S6. S5. Using the roller gap, guide plate gap and top extension as control quantities, the uneven state of perforation deformation is corrected. The uneven force component, the uneven guide constraint component and the uneven flow component are defined. The process parameters are corrected according to the deviation between each component and the target component. S6. Based on the corrected process parameters obtained in S6, roll again and repeat the contents of steps S1 to S6.

[0041] The following description, in conjunction with specific embodiments, illustrates this point.

[0042] The production of seamless steel tubes is controlled according to the following steps: S1. Obtain relevant data on the production process of the perforation deformation zone; Taking a tube with a nominal wall thickness of 23.5 mm as an example, in this embodiment, the billet steel grade, heating regime, roll speed, and equipment structure remain unchanged. The roll gap, guide plate distance, and top extension are used as the main adjustment parameters for controlling the tube wall thickness accuracy. The initial setting parameters are: roll gap... E 0 = 181.1 mm, guide plate distance A 0=206.0mm, top extension L 0 = 124.0 mm.

[0043] Online detection yielded the following temperatures at symmetrical positions on the left and right guide plates in the perforation deformation zone: T 1 = 1186℃ T 2 = 1162℃; the contact pressures at the symmetrical positions of the upper and lower rolls are respectively p 1 = 154 MPa p 2 = 142 MPa; the metal flow velocities at the symmetrical positions of the left and right guide plates are respectively v 1 = 1.28 m / s v 2 = 1.14 m / s; diameter of the guide zone tip D =178.0mm; Lateral offset of the capillary center relative to the guide center y =1.20mm.

[0044] The data that needs to be calculated is as follows: Calculate the average of the data:

[0045]

[0046]

[0047]

[0048] Calculate the uneven difference:

[0049]

[0050]

[0051]

[0052] Equivalent guiding constraint at symmetrical positions of the left and right guide plates g 1. g 2. The calculation method is as follows:

[0053]

[0054] Among them: the reference contact length is measured on site. =100mm; Reference contact pressure =10MPa; the contact lengths on both sides are respectively =42mm =31mm; the average contact pressure on both sides is respectively =9.0MPa =7.4MPa. Take the correction factor. l 1 = 0.20 l 2 = 0.10, a tiny positive number e =0.50mm.

[0055] Calculations show that:

[0056]

[0057]

[0058]

[0059] S2. Construct the perforation deformation non-uniformity coefficient based on the key state parameters described in S1; Construct the perforation deformation non-uniformity coefficient:

[0060] The coefficient of deformation non-uniformity K u Used to characterize the degree of inconsistency between the temperature field, force field, flow field, and guiding constraint state during the perforation process; K u The larger the value, the more severe the uneven deformation in the perforated area.

[0061] To ensure computational stability, the following values ​​are used during the calculation: a =0.20、 b =0.30、 c =0.25、 d =0.25.

[0062] Therefore, the deformation non-uniformity coefficient of this capillary tube can be calculated:

[0063] S3. Define the capillary wall thickness deviation coefficient and establish the relationship between the wall thickness deviation coefficient and the deformation unevenness coefficient; (1) Define the capillary wall thickness deviation coefficient:

[0064] in:S max This represents the maximum wall thickness of the capillary tube. S min This represents the minimum wall thickness of the capillary tube. Online thickness measurement results show that the maximum wall thickness of the capillary tube under initial operating conditions is... S max =24.32mm, minimum wall thickness S min =22.82mm. The capillary wall thickness deviation coefficient can be calculated as follows: d s =0.0636.

[0065] (2) Establish the relationship between the wall thickness deviation coefficient and the deformation unevenness coefficient:

[0066] in: C u The wall thickness response coefficient is obtained through calibration using on-site production data to ensure consistent wall thickness deviations caused by the same degree of deformation unevenness under the same specifications. The wall thickness response coefficient can be obtained by calibrating a batch of capillary tubes of this specification. C u =0.60.

[0067] S4. Based on the allowable wall thickness deviation of the target product, determine the target deformation non-uniformity coefficient. Simultaneously, compare the deformation non-uniformity coefficient in S2 with the target deformation non-uniformity coefficient. If the deformation non-uniformity coefficient in S2 is greater than the target deformation non-uniformity coefficient, proceed to the following steps; otherwise, output the final optimized process parameters (roller gap). E fina guide plate distance A fina and top extension L fina ); According to the production requirements of this specification, the allowable wall thickness deviation coefficient is: d lim =0.04. Based on the relationship between the wall thickness response coefficient, wall thickness deviation coefficient, and deformation non-uniformity coefficient obtained in S3, the target deformation non-uniformity coefficient can be calculated as follows: .

[0068] By comparing the deformation coefficient obtained in S2 with the target deformation coefficient obtained this time, we can obtain... K u > Therefore, this capillary tube does not meet the requirements and needs to be adjusted. Continue to perform the following steps.

[0069] S5. Using the roller gap, guide plate gap and top extension as control quantities, the uneven state of perforation deformation is corrected. The uneven force component, the uneven guide constraint component and the uneven flow component are defined. The process parameters are corrected according to the deviation between each component and the target component. (1) Define the component of uneven force. K P Uneven component of guidance constraints K G and flow non-uniformity components K V They are respectively:

[0070] (2) Define the target values ​​for each component:

[0071] (3) Adjust the roller spacing E guide plate distance A and top extension L Adjust as follows:

[0072] in: k E , k A , k L The correction factors, calculated based on actual production conditions, are -145.9, -144.5, and -156.3. From this, a new set of parameter combinations can be obtained through calculation. E 1 = 181.22 mm A 1 = 210.33 mm L 1 = 125.46 mm.

[0073] S6. Based on the set parameters obtained in S5, roll again and repeat the contents of steps S1 to S6. Using the new parameter combination obtained in S5, production data is collected during production, and a new deformation coefficient is calculated. =0.0409, by comparing with the target deformation coefficient in S4 =0.0667. Comparison shows that the wall thickness is within the allowable error range.

[0074] In this embodiment, the parameter setting data and output quality data of one of the capillaries are shown in Table 1, and the parameter setting data and capillary quality index data obtained through this optimized control method are shown in Table 2.

[0075] Table 1 Original on-site parameters and quality indicators

[0076] Table 2 Optimized parameter settings and quality indicators

[0077] Combination Figure 2 Comparing the two methods in Table 1 and Table 2, it can be found that using the optimized parameters can make the actual wall thickness of the capillary closer to the target value and with less fluctuation. This indicates that by using the method of the present invention, the wall thickness accuracy of the capillary with a nominal wall thickness of 23.5mm can be effectively controlled, wall thickness unevenness can be reduced, and dimensional consistency can be improved.

[0078] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A method for controlling the accuracy of perforated wall thickness in seamless steel pipes based on the deformation non-uniformity coefficient, characterized in that, The method includes: S1. Obtain relevant data on the production process of the perforation deformation zone; S2. Construct the perforation deformation non-uniformity coefficient based on the data obtained in S1. K u ; S3. Define the capillary wall thickness deviation coefficient and establish the relationship between the wall thickness deviation coefficient and the deformation unevenness coefficient; S4. Based on the allowable wall thickness deviation of the target product, determine the target deformation non-uniformity coefficient. At the same time, compare the deformation non-uniformity coefficient constructed in S2 with the target deformation non-uniformity coefficient. If the deformation non-uniformity coefficient in S2 is not greater than the target deformation non-uniformity coefficient, output the final optimized process parameters; otherwise, continue to execute S5 and S6. S5. Using the roller gap, guide plate gap and top extension as control quantities, the uneven state of perforation deformation is corrected. The uneven force component, the uneven guide constraint component and the uneven flow component are defined. The process parameters are corrected according to the deviation between each component and the target component. S6. Based on the corrected process parameters obtained in S6, roll again and repeat the contents of steps S1 to S6.

2. The method for controlling the accuracy of perforated wall thickness of seamless steel pipe based on the deformation non-uniformity coefficient according to claim 1, characterized in that, The relevant data for the perforation deformation zone production process in S1 includes the current maximum wall thickness of the capillary tube. S max Minimum wall thickness S min The current roller spacing used for perforation E 0. Guide plate distance A 0. Top extension L 0; The temperature of the perforated deformation zone at the symmetrical position of the contact area between the left and right guide plates and the capillary tube, obtained by on-site measurement. T 1. T 2; The contact pressure at the symmetrical position of the contact area between the upper and lower rolls and the tube obtained by on-site measurement. p 1. p 2; The metal flow velocity at the symmetrical position of the contact area between the left and right guide plates and the capillary tube, obtained through on-site measurement. v 1. v 2; Diameter of the guide zone top D Lateral offset of the capillary center relative to the guide center y ;No. i Actual contact length between the side guide plate and the capillary tube ; No. i Side average contact pressure Reference contact length Reference contact pressure And the equivalent guiding constraint at the symmetrical positions of the left and right guide plates. g 1. g 2.

3. The method for controlling the accuracy of perforated wall thickness of seamless steel pipe based on the deformation non-uniformity coefficient according to claim 2, characterized in that, The equivalent guiding constraint g 1. g 2. The calculation method is as follows: in, A The guide plate distance; λ 1. λ 1 is a correction factor, obtained by fitting actual production data from the field; ε To avoid small positive numbers with a denominator of zero, the value takes any value between [0,1] when the denominator is not zero, and takes 1 when the denominator is zero.

4. The method for controlling the wall thickness accuracy of seamless steel pipe perforation based on the deformation non-uniformity coefficient according to claim 1, characterized in that, The perforation deformation non-uniformity coefficient in S2 K u The construction process is as follows: S21. Calculate the average value of the data: in, The average temperature of the left and right guide plates in the perforated deformation zone. Temperature of the left guide plate in the perforated deformation zone. The temperature of the right guide plate is located symmetrically to the left guide plate in the perforation deformation zone. This represents the average contact pressure between the upper and lower rolls. The contact pressure of the upper roll. To achieve the contact pressure of the lower roll, which is symmetrical to the upper roll, This represents the average metal flow velocity of the left and right guide plates. The metal flow velocity of the left guide plate. The metal flow velocity of the right guide plate, which is symmetrical to the left guide plate. The average value of the equivalent guiding constraint quantity. , This represents the equivalent constraint quantity at the symmetrical positions of the left and right guide plates; S22. Calculate the unevenness difference: in, The difference in temperature between the left and right guide plates at symmetrical positions in the perforated deformation zone. This represents the difference in contact pressure between the symmetrical positions of the upper and lower rolls. This represents the difference in metal flow velocity at symmetrical positions on the left and right guide plates. The difference in equivalent guiding constraint amount between the symmetrical positions of the left and right guide plates; S23, Constructing the coefficient of non-uniform perforation deformation K u : in: a , b , c , d Let the weighting coefficients satisfy: 。 5. The method for controlling the wall thickness accuracy of seamless steel pipe perforation based on the deformation non-uniformity coefficient according to claim 1, characterized in that, The capillary wall thickness deviation coefficient in S3 for: in: S max This represents the maximum wall thickness of the capillary tube. S min This is the minimum wall thickness of the capillary tube.

6. The method for controlling the wall thickness accuracy of seamless steel pipe perforation based on the deformation non-uniformity coefficient according to claim 1, characterized in that, The relationship between the wall thickness deviation coefficient and the deformation unevenness coefficient in S3 is as follows: in: C u The wall thickness response coefficient is obtained by calibrating on-site production data to ensure consistent wall thickness deviation caused by the same degree of deformation unevenness under the same specifications.

7. The method for controlling the wall thickness accuracy of seamless steel pipe perforation based on the deformation non-uniformity coefficient according to claim 1, characterized in that, The target deformation non-uniformity coefficient in S4 for: in, δ lim The allowable wall thickness deviation for the current target product. C u is the wall thickness response coefficient.

8. The method for controlling the accuracy of perforated wall thickness of seamless steel pipe based on the deformation non-uniformity coefficient according to claim 1, characterized in that, In step S4, if the deformation non-uniformity coefficient in S2 is less than the target deformation non-uniformity coefficient, then the current process parameters are directly output as the final optimized process parameters. These process parameters include the roll gap. E fina guide plate distance A fina and top extension L fina .

9. The method for controlling the accuracy of perforated wall thickness of seamless steel pipe based on the deformation non-uniformity coefficient according to claim 1, characterized in that, The uneven force component in S5 K P Uneven component of guidance constraints K G and flow non-uniformity components K V Specifically: in, This represents the difference in contact pressure between the symmetrical positions of the upper and lower rolls. This represents the difference in metal flow velocity at symmetrical positions on the left and right guide plates. The difference in equivalent guiding constraint amount between the symmetrical positions of the left and right guide plates is the value of the unevenness. b , c , d These are the weighting coefficients; The target component in S5 is specifically: in, , , These are the target components of the force non-uniformity component, the guiding constraint non-uniformity component, and the flow non-uniformity component, respectively. a , b , c , d The weighting coefficients are determined by fitting different parameters and corresponding wall thickness data from actual on-site production. The difference in temperature between the left and right guide plates at symmetrical positions in the perforated deformation zone. The average temperature of the left and right guide plates in the perforated deformation zone. This represents the temperature non-uniformity component. The process parameters in S5 include the roller spacing. E guide plate distance A and top extension L， The specific revisions are as follows: in, , , These are the corrected roller gap, guide plate distance, and top extension, respectively. , , These are the roller spacing, guide plate spacing, and top extension amount used for the previous steel pipe, respectively. k E , k A , k L The correction factor was determined based on the actual production conditions on site. i This is the serial number of the steel pipe.

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