A method for optimizing setting of process parameters for outer diameter of seamless steel pipe

Abstract

This invention discloses a method for optimizing and setting process parameters for the outer diameter of seamless steel pipes, belonging to the field of seamless steel pipe rolling technology. The method includes: establishing a prediction model for the outer diameter of seamless steel pipes based on the production process parameters; determining the process parameters to be optimized and their allowable adjustment ranges; determining adjustment strategies for process parameters under different degrees of outer diameter deviation; and, based on the prediction model, the allowable adjustment ranges of the process parameters to be optimized, and the adjustment strategies under different degrees of outer diameter deviation, combined with actual production process requirements, constructing a process parameter optimization and setting model with the goal of minimizing the outer diameter deviation of the seamless steel pipe, thereby achieving optimized setting of the process parameters. Using this method for optimizing and setting process parameters for the outer diameter of seamless steel pipes can improve the control accuracy of the outer diameter of seamless steel pipes and make the optimization and setting of process parameters more accurate.

Description

Technical Field

[0001] This invention relates to the field of seamless steel pipe rolling technology, and in particular to a method for optimizing and setting process parameters for the outer diameter of seamless steel pipes. Background Technology

[0002] Seamless steel pipes are widely used in the oil, natural gas, and chemical industries, thus requiring stringent precision in their outer diameter dimensions. During hot rolling production, process parameters such as piercing, rolling, and diameter reduction have a decisive impact on the outer diameter. For thick-walled seamless steel pipes, production is typically characterized by "multiple specifications, small batches," leading to frequent modifications to process parameters. Currently, in actual production, controlling outer diameter precision still relies heavily on operator experience, manually modifying process parameters for each stage based on the actual measurement results of the previous pipe. This highly experience-dependent control method introduces significant uncertainty and lag in parameter setting, resulting in large overall deviations in the outer diameter dimensions of some batches of steel pipes. Summary of the Invention

[0003] This invention provides a method for optimizing the setting of process parameters for the outer diameter of seamless steel pipes, in order to solve the technical problem that current methods for optimizing the outer diameter of seamless steel pipes produce significant uncertainties and lags in parameter setting, resulting in large overall deviations in the outer diameter of some batches of steel pipes.

[0004] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0005] On one hand, the present invention provides a method for optimizing and setting process parameters for the outer diameter of seamless steel pipes, including:

[0006] Establish a prediction model for the outer diameter of seamless steel pipes based on the production process parameters of seamless steel pipes;

[0007] Identify the process parameters that need to be optimized, and determine the allowable adjustment range for each process parameter that needs to be optimized;

[0008] Determine the process parameter adjustment strategy under different outer diameter deviations;

[0009] Based on the seamless steel pipe outer diameter prediction model, the allowable adjustment range of each process parameter that needs to be optimized, and the process parameter adjustment strategy under different outer diameter deviations, combined with the actual production process requirements, and with the goal of minimizing the outer diameter deviation of seamless steel pipes, a process parameter optimization setting model is constructed to achieve the optimized setting of process parameters.

[0010] Furthermore, the process parameters that need to be optimized are identified, and the allowable adjustment range for each process parameter that needs to be optimized is determined, including:

[0011] Identify the process parameters that can be modified in real time during the piercing, rolling, and diameter reduction deformation of seamless steel pipes, and use them as candidate process parameters.

[0012] Correlation analysis was performed on the candidate process parameters, and the parameters that had the greatest impact on the outer diameter of the seamless steel pipe were selected as the process parameters that need to be optimized.

[0013] Determine the allowable adjustment range for each process parameter that needs to be optimized.

[0014] Furthermore, the process parameters that need to be optimized include: the top extension of the piercing mill, the guide plate distance of the piercing mill, the roll gap of the piercing mill, the throat diameter of the tube rolling mill, and the roll speed of each stand of the reducing mill.

[0015] Furthermore, the process parameter adjustment strategies for different degrees of outer diameter deviation are determined, including:

[0016] Determine the range of seamless steel pipe outer diameter deviation [Δd] that can be adjusted by modifying process parameters. min Δd max ];

[0017] If the outer diameter deviation of the seamless steel pipe is within [Δd] min [Δd0] or [Δd3, Δd] max If the deviation of the seamless steel pipe's outer diameter is within the range of [Δd0, Δd1] or [Δd2, Δd3], then simultaneously optimize the piercing mill top extension, piercing mill guide plate distance, piercing mill roll gap, tube rolling mill throat diameter, and the roll speed of each stand in the reducing mill; if the deviation of the seamless steel pipe's outer diameter is within the range of [Δd1, Δd2], then no adjustment is made; where Δd min Δd represents the minimum outer diameter of the seamless steel pipe that can be adjusted by modifying process parameters. max This represents the maximum outer diameter of the seamless steel pipe that can be adjusted by modifying process parameters; Δd0, Δd1, Δd2, and Δd3 are different preset values, and Δd min <Δd0<Δd1<0<Δd2<Δd3<Δd max .

[0018] Furthermore, based on the seamless steel pipe outer diameter prediction model, the allowable adjustment range of each process parameter that needs optimization, and the process parameter adjustment strategies under different outer diameter deviations, combined with actual production process requirements, and with the goal of minimizing the outer diameter deviation of the seamless steel pipe, a process parameter optimization setting model is constructed to achieve optimized setting of process parameters, including:

[0019] Step 1: Based on the seamless steel pipe outer diameter prediction model, obtain the predicted value of the seamless steel pipe outer diameter in the current production process, and calculate the current seamless steel pipe outer diameter deviation value x0 in combination with the actual production process requirements.

[0020] Step 2, if x0 is less than Δd min or greater than Δd max If it is determined that the outer diameter cannot be adjusted simply by modifying process parameters, an alarm will be issued, suggesting: Replace the tooling; if x0 is within [Δd]... min [Δd0] or [Δd3, Δd] max If x0 is within the range of [Δd0, Δd1] or [Δd2, Δd3], proceed to step 3; if x0 is within the range of [Δd1, Δd2], proceed to step 5; if x0 is within the range of [Δd1, Δd2], it is determined that the optimization goal has been achieved, and production is carried out using the current process parameters.

[0021] Step 3: Obtain the adjustment amounts of the piercing mill top extension, piercing mill guide plate distance, piercing mill roll gap, tube rolling mill throat diameter, and roll speed of each stand in the reducing mill. Obtain multiple different combinations of these parameter adjustment amounts. Input each combination into the seamless steel pipe outer diameter prediction model to obtain the predicted outer diameter value for the corresponding combination, and calculate the outer diameter deviation value for the corresponding combination. If the outer diameter deviation value for a certain combination is within the range [Δd1, Δd2], save this combination, perform inverse normalization to obtain the optimal process parameters, and issue them to the production system. If the outer diameter deviation values ​​for all combinations are within the range [Δd0, Δd1] or [Δd2, Δd3], proceed to Step 5. If the outer diameter deviation values ​​for all combinations are within the range [Δd0, Δd1] or [Δd2, Δd3], proceed to Step 5. min [Δd0] or [Δd3, Δd] max If the condition is within the specified range, proceed to step 4.

[0022] Step 4: The combination of the two minimum outer diameter deviation values ​​obtained in Step 3, or the combination of the smallest positive and negative deviation values, forms an interval as the optimization range for the piercing mill roll gap, piercing mill guide plate distance, piercing mill top extension, and tube mill throat diameter. The adjustment amount of the roll speed of each stand of the reducing mill calculated in Step 3 is used as the initial value to optimize the piercing mill roll gap, piercing mill guide plate distance, piercing mill top extension, tube mill throat diameter, and roll speed of each stand of the reducing mill.

[0023] Step 5: Obtain the adjustment amounts of the guide plate distance of the piercing mill, the throat diameter of the tube rolling mill, and the rotational speed of the rolls on each stand of the reducing mill. Obtain multiple different combinations of these adjustment amounts. Input each combination into the seamless steel pipe outer diameter prediction model to obtain the predicted outer diameter value for the corresponding combination, and calculate the outer diameter deviation value for the corresponding combination. If the outer diameter deviation value corresponding to a certain combination is within the range of [Δd1, Δd2], save this combination, perform inverse normalization to obtain the optimal process parameters, and issue them to the production system. If the outer diameter deviation values ​​corresponding to all combinations are within the range of [Δd0, Δd1] or [Δd2, Δd3], proceed to Step 6.

[0024] Step 6: The range corresponding to the combination of the two minimum outer diameter deviation values ​​obtained in Step 5, or the combination of the positive and negative deviations with the smallest deviation values, is used as the optimization range for the guide plate distance of the piercing mill and the throat diameter of the tube rolling mill. The adjustment amount of the roll speed of each stand of the reducing mill calculated in Step 5 is used as the initial value to optimize the guide plate distance of the piercing mill, the throat diameter of the tube rolling mill, and the roll speed of each stand of the reducing mill.

[0025] Furthermore, the adjustment amount of each parameter is obtained by dividing the allowable adjustment range of each process parameter into average segments; and determining the adjustment amount of each process parameter based on the segmentation results.

[0026] The adjustment amount of the guide plate distance of the perforating machine must meet the following formula:

[0027]

[0028] In the formula, b is the roll gap; l is the guide plate distance of the piercing mill; d z d0 is the diameter of the tube blank; d0 is the diameter of the tube cap.

[0029] The roll speeds of each stand in the reducing mill are calculated using the following formula:

[0030]

[0031] In the formula, d i d is the outer diameter of the steel pipe after passing through the i-th frame; i0 Let be the bore diameter of the i-th rack; i is the rack number; x is the current outer diameter deviation; a is the number of racks currently in use; N i N is the rotational speed of the i-th rack; i+1 d is the rotational speed of the (i+1)th rack; i+1 s is the outer diameter of the steel pipe after passing through the (i+1)th frame; s is the wall thickness of the rough pipe.

[0032] Furthermore, the optimized functions for the roll gap of the piercing mill, the guide plate distance of the piercing mill, the top extension of the piercing mill, the throat diameter of the tube rolling mill, and the roll speeds of each stand in the reduction mill are expressed as follows:

[0033]

[0034] In the formula, D p Δn represents the outer diameter deviation; b represents the roll gap; l represents the guide plate spacing of the piercing mill; y represents the mandrel extension of the piercing mill; e represents the throat diameter of the tube rolling mill; A represents the optimization range for the roll gap, guide plate spacing, mandrel extension, and throat diameter of the piercing mill; a represents the number of stands currently in use; Δn i Let Δn be the speed difference between the i-th frame and the previous frame; i+1 n represents the speed difference between the (i+1)th rack and the previous rack; i Let n be the rotational speed of the i-th rack; i+1 Let be the rotational speed of the (i+1)th rack; i is the rack number.

[0035] The Particle Swarm Optimization (PSO) algorithm is used to find the optimal solution for the optimization functions of the piercing mill roll gap, piercing mill guide plate distance, piercing mill top extension, tube mill throat diameter, and the roll speeds of each stand in the reduction mill. When the obtained solution corresponds to D... p When the value is within [Δd1, Δd2], stop optimization, save the combination of process parameters corresponding to the optimal solution, perform inverse normalization to obtain the optimal process parameters, and then issue them to the production system.

[0036] Furthermore, the optimized functions for the guide plate distance of the piercing mill, the throat diameter of the tube rolling mill, and the roll speeds of each stand in the reducing mill are expressed as follows:

[0037]

[0038] In the formula, D p b is the outer diameter deviation; e is the roll gap; b is the tube mill throat diameter; B is the optimized range for the piercing mill guide plate distance and the tube mill throat diameter; a is the number of stands currently in use; Δn i Let Δn be the speed difference between the i-th frame and the previous frame; i+1 Let n be the rotational speed difference between the (i+1)th rack and the previous rack; i Let n be the rotational speed of the i-th rack; i+1 Let be the rotational speed of the (i+1)th rack; i is the rack number.

[0039] The optimal solution for the optimization function of the guide plate distance of the piercing mill, the throat diameter of the tube rolling mill, and the roll speed of each stand in the reduction mill is obtained using PSO. When the obtained solution corresponds to D p When the value is within the range of [Δd1, Δd2], the optimization is stopped, the combination of process parameters corresponding to the optimal solution is saved, and after inverse normalization, the optimal process parameters are obtained and issued to the production system.

[0040] In another aspect, the present invention also provides an electronic device comprising a processor and a memory; wherein the memory stores at least one instruction, which is loaded and executed by the processor to implement the above-described method.

[0041] In another aspect, the present invention also provides a computer-readable storage medium storing at least one instruction, which is loaded and executed by a processor to implement the above method.

[0042] The beneficial effects of the technical solution provided by this invention include at least the following:

[0043] 1. The technical solution of the present invention predicts the outer diameter of the finished tube based on the process parameters of the three deformation processes of piercing, rolling and reducing, which provides support for the coordinated optimization of the process parameters of the three deformation processes.

[0044] 2. The technical solution of the present invention divides the process parameter combinations according to different outer diameter deviations, which is beneficial to improving the optimization speed and accuracy of the particle swarm algorithm.

[0045] 3. The technical solution of this invention is based on the outer diameter prediction model. An optimization setting model for the hot rolling process parameters of seamless steel pipe is established with the goal of minimizing the deviation between the predicted outer diameter and the target outer diameter. This is conducive to realizing the automatic optimization and pre-setting of process parameters and improving the stability of parameter control. Attached Figure Description

[0046] 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.

[0047] Figure 1 This is a flowchart of the seamless steel pipe outer diameter process parameter optimization setting method provided in the embodiments of the present invention;

[0048] Figure 2 This is a flowchart of the process parameter optimization algorithm provided in the embodiments of the present invention;

[0049] Figure 3 This is a system block diagram of the electronic device provided in the embodiments of the present invention. Detailed Implementation

[0050] To make the objectives, technical solutions, and advantages of the present invention clearer, the embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

[0051] First, it should be noted that in the embodiments of the present invention, the words "exemplarily," "for example," etc., are used to indicate that they are examples, illustrations, or descriptions. Any embodiment or design scheme described as "exemplary" in the present invention should not be construed as being more preferred or advantageous than other embodiments or design schemes. Specifically, the use of the term "exemplarily" is intended to present the concept in a specific manner. Furthermore, in the embodiments of the present invention, the meaning expressed by "and / or" can be both, or it can be either one or the other.

[0052] First Embodiment

[0053] This embodiment provides a method for optimizing the setting of process parameters for the outer diameter of seamless steel pipes, which can be implemented by electronic equipment. The execution flow of this method is as follows: Figure 1 As shown, it includes the following steps:

[0054] S1, Establish a prediction model for the outer diameter of seamless steel pipes based on the production process parameters of seamless steel pipes;

[0055] Specifically, in this embodiment, the implementation process of S1 is as follows: A prediction model for the outer diameter of the seamless steel pipe is established based on the production process parameters of the piercing, rolling, and diameter reduction deformation processes. The construction process is as follows:

[0056] S11. Collect production process parameters and production quality data for the piercing, tube rolling, and diameter reduction deformation processes during hot rolling production. The process parameters include: furnace exit temperature, roll gap, mandrel diameter, mandrel length, mandrel extension, feed angle, rolling angle, guide plate distance, roll speed, and roll bite speed during the piercing stage; throat diameter, mandrel diameter, mandrel speed, feed angle, rolling angle, and roll speed during the tube rolling stage; and last stand pass type, number of stands, roll speed of each stand, and incoming steel grade and specifications during the diameter reduction stage. The production quality data refers to the outer diameter of the finished tube corresponding to the production process parameters.

[0057] S12, perform outlier detection and normalization on the training sample data to generate training samples for the seamless steel pipe outer diameter prediction model.

[0058] S13, Construct a prediction model for the outer diameter of seamless steel pipes using the Support Vector Regression (SVR) algorithm. S2, Determine the process parameters that need optimization and the allowable adjustment range for each optimized process parameter;

[0059] Specifically, in this embodiment, the implementation process of S2 is as follows:

[0060] S21. Based on the steel pipe rolling mechanism, determine the process parameters that can be modified in real time during the piercing, rolling, and diameter reduction deformation of seamless steel pipes, and use them as candidate process parameters.

[0061] S22, perform correlation analysis on the above candidate process parameters, and select the process parameters that have a greater impact on the outer diameter of seamless steel pipes as the optimization settings, specifically including: piercing mill top extension, piercing mill guide plate distance, piercing mill roll gap, tube rolling mill throat diameter, and roll speed of each stand of the reducing mill.

[0062] S23, determine the range of allowable optimization for the selected process parameters, as shown in Table 1.

[0063] Table 1 Allowable Adjustment Range of Parameters

[0064]

[0065] S3, determine the process parameter adjustment strategy under different outer diameter deviations;

[0066] Specifically, in this embodiment, the implementation process of S3 is as follows:

[0067] S31, the range of outer diameter deviation that can be adjusted by modifying process parameters [-4.5mm, 4.5mm] was determined through industrial experiments;

[0068] S32, determine the process parameters to be adjusted for different degrees of outer diameter deviation and their adjustment methods, specifically including: when the outer diameter deviation is within the range of [2.5mm, 4.5mm] or [-4.5mm, -2.5mm], it is necessary to simultaneously optimize the piercing mill top extension, piercing mill guide plate distance, piercing mill roll gap, tube rolling mill throat diameter, and the roll speed of each stand in the reducing mill; when the outer diameter deviation is within the range of [0.5mm, 2.5mm] or [-2.5mm, -0.5mm], it is necessary to simultaneously optimize the piercing mill guide plate distance, tube rolling mill throat diameter, and the roll speed of each stand in the reducing mill; when the outer diameter deviation is within the range of [-0.5mm, 0.5mm], no adjustment is required. The process parameter adjustment methods are shown in Table 2.

[0069] Table 2. Methods for Adjusting Process Parameters

[0070]

[0071] In this symbol, "↓" indicates a decrease, and "↑" indicates an increase.

[0072] S4. Based on the seamless steel pipe outer diameter prediction model, the allowable adjustment range of each process parameter that needs to be optimized, and the process parameter adjustment strategy under different outer diameter deviations, combined with the actual production process requirements, and with the goal of minimizing the outer diameter deviation of the seamless steel pipe, a process parameter optimization setting model is constructed to achieve the optimized setting of process parameters.

[0073] Specifically, in this embodiment, the implementation process of S4 is as follows:

[0074] S41, based on the optimization range and adjustment strategy of the process parameters, formulate the initial adjustment combination of each process parameter. Specifically, this includes: dividing the allowable adjustment range of each process parameter into equal segments according to the adjustment strategy for different outer diameter deviations, to obtain the adjustment combination of each piercing mill and tube rolling mill process parameter under different outer diameter deviations; specifically: for the piercing mill top extension, piercing mill guide plate distance, piercing mill roll gap, and tube rolling mill throat diameter, select at least one data point as the adjustment amount within each segment of its allowable adjustment range according to its adjustment strategy; and the setting of the preset parameter adjustment amount for the piercing mill guide plate distance must satisfy the following formula:

[0075]

[0076] In the formula: b is the roll gap, mm; l is the guide plate spacing, mm; d z d0 is the diameter of the tube blank, in mm; d0 is the diameter of the tube cap, in mm.

[0077] Based on industrial experiments, the adjustment range of the guide plate distance of the perforating machine is as follows:

[0078] 1.06b≤l≤1.16b

[0079] In this embodiment, when the outer diameter deviation is within the range of [2.5mm, 4.5mm], the preset adjustment combination of the process parameters of the piercing mill and the tube rolling mill is as follows: [piercing mill roll gap, piercing mill overhang, tube rolling mill throat diameter]: [-2mm, 18mm, -6mm], [-1.5mm, 13.5mm, -4.5mm], [-1mm, 9mm, -3mm], [-0.5mm, 4.5mm, -1.5mm]. The guide plate distance is set to 1.1 times the roll gap of the piercing mill; when the outer diameter deviation is within the range of [0.5mm, 2.5mm], the preset adjustment combination of the process parameters of the piercing mill and the tube rolling mill is [piercing mill guide plate distance, tube rolling mill throat diameter]: [1.06b, -2.5mm], [1.07b, -2mm], [1.08b, -1.5mm], [1.09b, -1mm], [1.1b, -0.5mm], [1.11b] When the outer diameter deviation is within the range of [-4.5mm, -2.5mm], the preset adjustment combination of the process parameters of the piercing mill and the tube rolling mill is as follows: [piercing mill roll gap, piercing mill top extension, tube rolling mill throat diameter]: [2mm, -18mm, 6mm], [1.5mm, -13.5mm, 4.5mm], [1mm, -9mm, 3mm], [0.5mm, -4.5mm, 1.5mm], piercing mill guide plate The distance is set to 1.1 times the roll gap of the piercing mill; when the outer diameter deviation is within the range of [-2.5mm, -0.5mm], the preset adjustment combination of the process parameters of the piercing mill and the tube rolling mill is [piercing mill guide plate distance, tube rolling mill throat diameter]: [1.16b, 2.5mm], [1.15b, 2mm], [1.14b, 1.5mm], [1.13b, 1mm], [1.12b, 0.5mm], [1.11b, 0mm].

[0080] The rotational speed of each frame in the reducing mill is calculated using the following formula:

[0081]

[0082] In the formula: d i d represents the outer diameter of the steel pipe after passing through the i-th frame, in mm. i0 denoted as , where is the bore diameter of the i-th rack (in mm); 'x' is the outer diameter deviation (in mm); 'a' is the number of racks currently in use; N i is the rotational speed of the i-th frame, in r / min; s is the wall thickness of the rough tube, in mm.

[0083] S42, based on the outer diameter prediction value output by the seamless steel pipe outer diameter prediction model and the production process requirements, the outer diameter deviation value x0 is obtained;

[0084] S43: If x0 is less than -4.5mm or greater than 4.5mm, it is determined that the outer diameter cannot be adjusted by modifying the process parameters alone, and an alarm "It is recommended to change the tooling" is issued; if x0 is in the range of [-4.5mm, -2.5mm] or [2.5mm, 4.5mm], proceed to S44; if x0 is in the range of [-2.5mm, -0.5mm] or [0.5mm, 2.5mm], proceed to S46; if x0 is in the range of [-0.5mm, 0.5mm], it means that the optimization goal has been achieved, and production can be carried out using the currently set process parameters.

[0085] S44. The process parameters that need to be adjusted include the roll gap of the piercing mill, the guide plate distance of the piercing mill, the top extension of the piercing mill, the throat diameter of the tube rolling mill, and the roll speed of each stand of the reducing mill. At this time, four combinations of process parameters are obtained based on the preset adjustment combinations of the roll gap of the piercing mill, the guide plate distance of the piercing mill, the top extension of the piercing mill, and the throat diameter of the tube rolling mill, and the calculation method of the speed of each stand of the reducing mill. These combinations are then input into the prediction model to test the outer diameter deviation under all combinations. If the outer diameter deviation of any candidate combination is within the range of [-0.5mm, 0.5mm], this parameter combination is saved, denormalized, and then issued. If the outer diameter deviation is within the range of [-2.5mm, -0.5mm] or [0.5mm, 2.5mm], then proceed to S46. If all outer diameter deviations are within the range of [-4.5mm, -2.5mm] or [2.5mm, 4.5mm], then proceed to S45.

[0086] S45 uses the two sets of piercing and rolling process parameters with the smallest outer diameter deviation obtained in S44, or the positive and negative deviation combinations with the smallest deviation values, to form an interval to obtain the optimization range of piercing mill roll gap, piercing mill guide plate distance, piercing mill top extension, and rolling mill throat diameter. The combination of roll speeds of each stand of the reducing mill calculated in S44 is used as the initial value to further optimize the piercing mill roll gap, piercing mill guide plate distance, piercing mill top extension, rolling mill throat diameter, and roll speeds of each stand of the reducing mill.

[0087] In this process, the range formed by the two sets of piercing and rolling process parameters with the smallest outer diameter deviation obtained in the previous step, or the positive and negative deviation combinations with the smallest deviation values, determines the optimization range for the piercing mill roll gap, piercing mill guide plate distance, piercing mill top extension, and rolling mill throat diameter. It should be noted that although the variation law of the piercing and rolling process parameters on the outer diameter at the process exit is relatively clear, the outer diameter of the finished tube is affected by the combined effect of multiple processes. The process parameters of each process may restrict each other, thus making their variation law on the outer diameter of the finished tube unclear. Therefore, when the outer diameter deviations of all candidate combinations are concentrated in the range of [-4.5mm, -2.5mm] or [2.5mm, 4.5mm], it indicates that the optimal process parameter combination may have been missed in the pre-selection stage. In this case, if the outer diameter deviations have the same sign, the two sets of process parameter combinations with the smallest deviations are selected; if the outer diameter deviations have opposite signs, the positive and negative deviation combinations with the smallest deviation values ​​are selected respectively. Finally, the Particle Swarm Optimization (PSO) algorithm is used to perform a fine search for the optimal process parameter combination that may exist between these two sets of minimum deviations. The core objective of searching between two sets of minimum deviations is to capture potential optimal process parameter combinations. When the distribution of outer diameter deviations is concentrated within two deviation ranges (e.g., [-4.5mm, -2.5mm] or [2.5mm, 4.5mm]), there may be optimal solutions not covered by the initial candidate combinations. In this case, the two sets of parameter combinations with the minimum deviations usually represent the region closest to the optimal solution. If the deviations have the same sign, searching between the two sets of minimum deviations can narrow the range and quickly locate potential optimal solutions; if the signs are opposite, selecting the two sets with the smallest positive and negative deviations covers the transition points in the direction of process parameter adjustment, thereby more comprehensively uncovering hidden optimal process parameters. For example, if the outer diameter deviation is smallest among all the combinations of piercing and rolling process parameters, the two sets of adjustment values ​​[-1.5mm, 13.5mm, -4.5mm] and [-1mm, 9mm, -3mm] indicate that the optimal solution with the smallest outer diameter deviation lies between the two sets of process parameter combinations. Then, the optimization ranges for the piercing mill roll gap, piercing mill top extension, and rolling mill throat diameter are [-1.5mm, -1mm], [9mm, 13.5mm], and [-4.5mm, -3mm], respectively, and the piercing mill guide plate distance is 1.1 times the piercing mill roll gap.

[0088] Using the combination of roll speeds of each stand in the reducing mill calculated in the previous step as initial values, the roll gap of the piercing mill, the guide plate distance of the piercing mill, the top extension of the piercing mill, the throat diameter of the tube rolling mill, and the roll speeds of each stand in the reducing mill are further optimized. The specific function for optimizing these process parameters is as follows:

[0089]

[0090] In the formula: D pΔn represents the outer diameter deviation in mm; b represents the roll gap of the piercing mill in mm; l represents the guide plate spacing of the piercing mill in mm; y represents the mandrel extension of the piercing mill in mm; e represents the throat diameter of the tube rolling mill in mm; A represents the optimization range for the roll gap, guide plate spacing, mandrel extension, and throat diameter of the piercing mill; i n represents the speed difference between the i-th frame and the previous frame, in r / min; i The rotational speed of the i-th frame is expressed in r / min.

[0091] The PSO algorithm is used to solve the optimal solution of the above equation. Random values ​​are selected within the range A to initialize the piercing and rolling process parameters, using the combination of reducing mill roll speeds calculated in S44 as the initial values. When the outer diameter deviation D... p Stop the PSO optimization process when the value is within the range of [-0.5mm, 0.5mm].

[0092] S46. The parameters that need to be adjusted include the guide plate distance of the piercing mill, the throat diameter of the tube rolling mill, and the roll speed of each stand of the reducing mill. Based on the preset adjustment combination of the guide plate distance of the piercing mill and the throat diameter of the tube rolling mill, and the calculation method of the roll speed of each stand of the reducing mill, six combinations of process parameters that need to be adjusted are obtained. Input them into the prediction model to test the outer diameter deviation under all combinations. If the outer diameter deviation of a candidate combination is within the range of [-0.5mm, 0.5mm], then save this parameter combination, perform inverse normalization, and then issue the result; if all outer diameter deviations are within the range of [-2.5mm, -0.5mm] or [0.5mm, 2.5mm], then proceed to S47.

[0093] S47 uses the two sets of piercing and rolling process parameter combinations with the smallest outer diameter deviation obtained in S46, or the positive and negative deviation combinations with the smallest deviation values, to form an interval to obtain the optimization range of the piercing mill guide plate distance and the rolling mill throat diameter. If the outer diameter deviation obtained by the two sets of adjustment values ​​[1.14b, 1.5mm] and [1.13b, 1mm] are the smallest among all piercing and rolling process parameter combinations, then the optimization ranges of the piercing mill guide plate distance and the rolling mill throat diameter are [1.13b, 1.14b] and [1mm, 1.5mm], respectively, where b is the piercing mill roll gap. Using the combination of roll speeds of each stand in the reduction mill calculated in S46 as the initial values, the piercing mill guide plate distance, the rolling mill throat diameter, and the roll speeds of each stand in the reduction mill are further optimized. The process parameter optimization function is:

[0094]

[0095] In the formula: B is the optimized range of the guide plate distance of the piercing mill and the throat diameter of the tube rolling mill.

[0096] The PSO algorithm is used to solve the optimal solution of the above equation. Random values ​​are selected within the range B to initialize the piercing and rolling process parameters, using the combination of reducing mill roll speeds calculated in S46 as the initial values. When the outer diameter deviation D... P When the value is within the range of [-0.5mm, 0.5mm], stop the PSO optimization process, save this parameter combination, perform inverse normalization, and then issue the next parameter.

[0097] The parameter optimization process is as follows Figure 2 As shown in the figure. Following the optimization steps described above, the relevant parameters of the PSO algorithm were set as follows: particle swarm size of 24, learning factors c1 and c2 of 1.8, inertia weight w of 0.9, and a maximum allowed number of iterations of 60. A set of data with large outer diameter deviations during the production process was collected for optimization, and the optimization results are shown in Table 3. Table 3 shows that the outer diameter deviation was significantly reduced after optimization, and all process parameters changed, conforming to the rolling process mechanism of steel pipes. This proves the effectiveness of the parameter optimization model of this invention for optimizing the process parameters of hot rolling production lines.

[0098] Table 3 Results of Process Parameter Optimization

[0099]

[0100] In summary, this embodiment provides a method for optimizing the process parameters of seamless steel pipe outer diameter. This method employs predictive control technology for parameter optimization, solving the problem that traditional seamless steel pipe rolling process theory cannot fully consider the complex and ever-changing environment and numerous real-time variables in the actual rolling process. Simultaneously, it selects three deformation processes that significantly impact the outer diameter and can be modified in real time for adjustment. Compared to traditional predictive control technology that optimizes process parameters for a single process, this method achieves control over the dimensional accuracy of the seamless steel pipe outer diameter under the combined action of multiple processes. It also solves the uncertainty and lag problems caused by relying on production experience and manual modification for process parameter setting, thus improving the accuracy of outer diameter control. Furthermore, it uses industrial big data to establish the objective function, fully considering the complex and ever-changing conditions in the production process, making the optimized setting of process parameters more accurate.

[0101] Second Embodiment

[0102] This embodiment provides an electronic device, such as... Figure 3As shown, the electronic device includes a processor and a memory; wherein the processor and the memory can be connected via a communication bus; the memory stores at least one instruction, which is loaded and executed by the processor to implement the method of the first embodiment described above. Furthermore, the electronic device may also include a transceiver, the processor and the transceiver can be connected via a communication bus, and the transceiver is used to communicate with other devices.

[0103] Below, in conjunction with Figure 3 A detailed introduction to each component of this electronic device is provided below:

[0104] The processor is the control center of the electronic device. The electronic device may include multiple processors, each of which can be a single-core processor (single-CPU) or a multi-core processor (multi-CPU). The term "processor" can refer to a single processor or a collective term for multiple processing elements. For example, a processor can be one or more central processing units (CPUs), other general-purpose processors, application-specific integrated circuits (ASICs), or one or more integrated circuits configured to implement embodiments of the present invention, such as one or more digital signal processors (DSPs), one or more field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor can be a microprocessor or any conventional processor. The processor can perform various functions of the electronic device by running or executing software programs stored in memory and by calling data stored in memory.

[0105] In a specific implementation, as one example, the processor may include one or more CPUs, for example... Figure 3 CPU0 and CPU1 shown are, of course, merely illustrative examples.

[0106] The memory is used to store the software program that executes the solution of the present invention, and the processor controls its execution. For specific implementation methods, please refer to the above method embodiments, which will not be repeated here.

[0107] Optionally, the memory may be a read-only memory (ROM) or other type of static storage device capable of storing static information and instructions, random access memory (RAM) or other type of dynamic storage device capable of storing information and instructions, or electrically erasable programmable read-only memory (EEPROM), compact disc read-only memory (CD-ROM) or other optical disc storage, optical disc storage (including compressed optical discs, laser discs, optical discs, digital universal optical discs, Blu-ray discs, etc.), magnetic disk storage media or other magnetic storage devices, or any other medium capable of carrying or storing desired program code in the form of instructions or data structures and accessible by a computer, but not limited thereto. The memory may be integrated with the processor or may exist independently, and may be accessed through the interface circuit of the electronic device (…). Figure 3 (Not shown in the image) is coupled to the processor; however, this embodiment of the invention does not impose specific limitations on this.

[0108] The transceiver may include a receiver and a transmitter. Figure 3 (Not shown separately). The receiver is used to implement the receiving function, and the transmitter is used to implement the transmitting function. The transceiver can be integrated with the processor or exist independently, and is connected through the interface circuit of the electronic device (…). Figure 3 (Not shown in the image) is coupled to the processor, and this embodiment of the invention does not specifically limit this.

[0109] In addition, it should be noted that, Figure 3 The structure of the electronic device shown is not intended to limit the device. Actual devices may include more or fewer components than shown, or combine certain components, or have different component arrangements. Furthermore, the technical effects achieved by this electronic device when performing the method of the first embodiment described above can be referenced to the technical effects described in the first embodiment; therefore, they will not be repeated here.

[0110] Third Embodiment

[0111] This embodiment provides a computer-readable storage medium storing at least one instruction, which is loaded and executed by a processor to implement the method of the first embodiment described above. The computer-readable storage medium may be a ROM, random access memory, CD-ROM, magnetic tape, floppy disk, or optical data storage device, etc. The instruction stored therein can be loaded and executed by a processor in a terminal.

[0112] Furthermore, it should be noted that the present invention can be provided as a method, apparatus, or computer program product. Therefore, embodiments of the present invention can take the form of a completely or partially hardware embodiment, a completely or partially software embodiment, or an embodiment combining software and hardware aspects. Moreover, when implemented in software, embodiments of the present invention can take the form of a computer program product implemented on one or more computer-usable storage media containing computer-usable program code. The computer program product includes one or more computer instructions or computer programs. When the computer instructions or computer program are loaded or executed on a computer, all or part of the processes or functions described in the embodiments of the present invention are generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any usable medium accessible to a computer or a data storage device such as a server or data center containing one or more sets of usable media. The available medium can be a magnetic medium (e.g., floppy disk, hard disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium. A semiconductor medium can be a solid-state drive (SSD).

[0113] Embodiments of the present invention are described with reference to flowchart illustrations and / or block diagrams of methods, terminal devices (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, embedded processor, or other programmable data processing terminal device to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing terminal device, generate instructions for implementing the flowchart illustrations. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0114] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing terminal device to operate in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1The functions specified in one or more boxes. These computer program instructions may also be loaded onto a computer or other programmable data processing terminal equipment to cause a series of operational steps to be performed on the computer or other programmable terminal equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable terminal equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0115] It should also be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. The terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or terminal device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or terminal device. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or terminal device that includes said element. Furthermore, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, and B alone, where A and B can be singular or plural. Additionally, the character " / " in this text generally indicates an "or" relationship between the preceding and following objects, but it can also indicate an "AND / OR" relationship. Please refer to the context for specific interpretations. "At least one" refers to one or more items, while "more than" refers to two or more items. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of single or multiple items. For example, at least one of a, b, or c can be represented as: a, b, c, ab, ac, bc, or abc, where a, b, and c can be single or multiple.

[0116] Furthermore, it is understood that in various embodiments of the present invention, the order of the above-mentioned process numbers does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

[0117] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this invention.

[0118] In the several embodiments provided by this invention, it should be understood that the disclosed devices, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative. For instance, the division of functional modules / units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another device, or some features may be ignored or not executed. Furthermore, the shown or discussed mutual couplings or direct couplings or communication connections may be through some interfaces; indirect couplings or communication connections between devices or units may be electrical, mechanical, or other forms. Units described as separate components may or may not be physically separate, and components shown as units may or may not be physical units, i.e., they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs. Additionally, the functional units in the various embodiments of this invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0119] If the method is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0120] Finally, it should be noted that the above description is merely a preferred embodiment of the present invention. It should be pointed out that although preferred embodiments of the present invention have been described, those skilled in the art, once they understand the basic inventive concept of the present invention, can make several improvements and modifications without departing from the principles described herein. These improvements and modifications should also be considered within the scope of protection of the present invention. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of the embodiments of the present invention.

Claims

1. A method for optimizing and setting process parameters for the outer diameter of seamless steel pipes, characterized in that, include: Establish a prediction model for the outer diameter of seamless steel pipes based on the production process parameters of seamless steel pipes; Identify the process parameters that need to be optimized, and determine the allowable adjustment range for each process parameter that needs to be optimized; Determine the process parameter adjustment strategy under different outer diameter deviations; Based on the seamless steel pipe outer diameter prediction model, the allowable adjustment range of each process parameter that needs to be optimized, and the process parameter adjustment strategy under different outer diameter deviations, combined with the actual production process requirements, and with the goal of minimizing the outer diameter deviation of seamless steel pipes, a process parameter optimization setting model is constructed to achieve the optimized setting of process parameters. Determine the process parameter adjustment strategies for different degrees of outer diameter deviation, including: Determine the range of seamless steel pipe outer diameter deviation [Δd] that can be adjusted by modifying process parameters. min Δd max ]; If the outer diameter deviation of the seamless steel pipe is within [Δd] min [Δd0] or [Δd3, Δd] max Within the specified range, the following parameters are simultaneously optimized: piercing mill top extension, piercing mill guide plate distance, piercing mill roll gap, tube mill throat diameter, and roll speeds of each stand in the reduction mill. The optimization functions for these parameters are expressed as follows: ； The Particle Swarm Optimization (PSO) algorithm is used to find the optimal solution for the optimization functions of the piercing mill roll gap, piercing mill guide plate distance, piercing mill top extension, tube mill throat diameter, and the roll speeds of each stand in the reduction mill. When the obtained solution corresponds to... When the value is within [Δd1, Δd2], stop optimization, save the combination of process parameters corresponding to the optimal solution, perform inverse normalization to obtain the optimal process parameters, and issue them to the production system. If the outer diameter deviation of the seamless steel pipe is within the range of [Δd0, Δd1] or [Δd2, Δd3], then the guide plate distance of the piercing mill, the throat diameter of the tube rolling mill, and the roll speed of each stand of the reducing mill are simultaneously optimized; the optimization function for the guide plate distance of the piercing mill, the throat diameter of the tube rolling mill, and the roll speed of each stand of the reducing mill is expressed as: ； The optimal solution for the optimization function of the guide plate distance of the piercing mill, the throat diameter of the tube rolling mill, and the roll speed of each stand in the reduction mill is obtained using PSO. When the value is within the range of [Δd1, Δd2], stop the optimization, save the combination of process parameters corresponding to the optimal solution, perform inverse normalization to obtain the optimal process parameters, and then issue them to the production system. If the outer diameter deviation of the seamless steel pipe is within the range of [Δd1, Δd2], no adjustment is required; Where, Δd min Δd represents the minimum outer diameter of the seamless steel pipe that can be adjusted by modifying process parameters. max This represents the maximum outer diameter of the seamless steel pipe that can be adjusted by modifying process parameters; Δd0, Δd1, Δd2, and Δd3 are different preset values, and Δd min <Δd0<Δd1<0<Δd2<Δd3<Δd max ; y is the outer diameter deviation; b is the roll gap; l is the guide plate spacing of the piercing mill; y is the mandrel extension of the piercing mill; e is the throat diameter of the tube rolling mill; A is the optimization range of the roll gap, guide plate spacing, mandrel extension, and throat diameter of the piercing mill; a is the number of stands currently in use. Let be the speed difference between the i-th frame and the previous frame; The rotational speed difference between the (i+1)th rack and the previous rack; Let be the rotational speed of the i-th rack; Let be the rotational speed of the (i+1)th stand; i be the stand number; B be the optimization range for the guide plate distance of the piercing mill and the throat diameter of the tube rolling mill; Δd min , Δd0, Δd1, Δd2, Δd3, Δd max , The units for b, l, y, e, A, and B are all mm; , , and The units are all r / min.

2. The method for optimizing and setting process parameters for the outer diameter of seamless steel pipes as described in claim 1, characterized in that, Identify the process parameters that need optimization, and determine the allowable adjustment range for each process parameter, including: Identify the process parameters that can be modified in real time during the piercing, rolling, and diameter reduction deformation of seamless steel pipes, and use them as candidate process parameters. Correlation analysis was performed on the candidate process parameters, and the parameters that had the greatest impact on the outer diameter of the seamless steel pipe were selected as the process parameters that need to be optimized. Determine the allowable adjustment range for each process parameter that needs to be optimized.

3. The method for optimizing and setting process parameters for the outer diameter of seamless steel pipes as described in claim 1, characterized in that, The process parameters that need to be optimized include: the top extension of the piercing mill, the guide plate distance of the piercing mill, the roll gap of the piercing mill, the throat diameter of the tube rolling mill, and the roll speed of each stand of the reducing mill.

4. The method for optimizing and setting process parameters for the outer diameter of seamless steel pipes as described in claim 1, characterized in that, Based on the seamless steel pipe outer diameter prediction model, the allowable adjustment range of each process parameter that needs optimization, and the process parameter adjustment strategies under different outer diameter deviations, combined with actual production process requirements, and with the goal of minimizing the outer diameter deviation of seamless steel pipes, a process parameter optimization setting model is constructed to achieve optimized setting of process parameters, including: Step 1: Based on the seamless steel pipe outer diameter prediction model, obtain the predicted value of the seamless steel pipe outer diameter in the current production process, and calculate the current seamless steel pipe outer diameter deviation value x0 in combination with the actual production process requirements. Step 2, if x0 is less than Δd min or greater than Δd max If it is determined that the outer diameter cannot be adjusted simply by modifying process parameters, an alarm will be issued, suggesting: Replace the tooling; if x0 is within [Δd]... min [Δd0] or [Δd3, Δd] max If x0 is within the range of [Δd0, Δd1] or [Δd2, Δd3], proceed to step 3; if x0 is within the range of [Δd1, Δd2], proceed to step 5; if x0 is within the range of [Δd1, Δd2], it is determined that the optimization goal has been achieved, and production is carried out using the current process parameters. Step 3: Obtain the adjustment amounts of the piercing mill top extension, piercing mill guide plate distance, piercing mill roll gap, tube rolling mill throat diameter, and roll speed of each stand in the reducing mill. Obtain multiple different combinations of these parameter adjustment amounts. Input each combination into the seamless steel pipe outer diameter prediction model to obtain the predicted outer diameter value for the corresponding combination, and calculate the outer diameter deviation value for the corresponding combination. If the outer diameter deviation value for a certain combination is within the range [Δd1, Δd2], save this combination, perform inverse normalization to obtain the optimal process parameters, and issue them to the production system. If the outer diameter deviation values ​​for all combinations are within the range [Δd0, Δd1] or [Δd2, Δd3], proceed to Step 5. If the outer diameter deviation values ​​for all combinations are within the range [Δd0, Δd1] or [Δd2, Δd3], proceed to Step 5. min [Δd0] or [Δd3, Δd] max If the condition is within the specified range, proceed to step 4. Step 4: The combination of the two minimum outer diameter deviation values ​​obtained in Step 3, or the combination of the smallest positive and negative deviation values, forms an interval as the optimization range for the piercing mill roll gap, piercing mill guide plate distance, piercing mill top extension, and tube mill throat diameter. The adjustment amount of the roll speed of each stand of the reducing mill calculated in Step 3 is used as the initial value to optimize the piercing mill roll gap, piercing mill guide plate distance, piercing mill top extension, tube mill throat diameter, and roll speed of each stand of the reducing mill. Step 5: Obtain the adjustment amounts of the guide plate distance of the piercing mill, the throat diameter of the tube rolling mill, and the rotational speed of the rolls on each stand of the reducing mill. Obtain multiple different combinations of these adjustment amounts. Input each combination into the seamless steel pipe outer diameter prediction model to obtain the predicted outer diameter value for the corresponding combination, and calculate the outer diameter deviation value for the corresponding combination. If the outer diameter deviation value corresponding to a certain combination is within the range of [Δd1, Δd2], save this combination, perform inverse normalization to obtain the optimal process parameters, and issue them to the production system. If the outer diameter deviation values ​​corresponding to all combinations are within the range of [Δd0, Δd1] or [Δd2, Δd3], proceed to Step 6. Step 6: The range corresponding to the combination of the two minimum outer diameter deviation values ​​obtained in Step 5, or the combination of the positive and negative deviations with the smallest deviation values, is used as the optimization range for the guide plate distance of the piercing mill and the throat diameter of the tube rolling mill. The adjustment amount of the roll speed of each stand of the reducing mill calculated in Step 5 is used as the initial value to optimize the guide plate distance of the piercing mill, the throat diameter of the tube rolling mill, and the roll speed of each stand of the reducing mill.

5. The method for optimizing and setting process parameters for the outer diameter of seamless steel pipes as described in claim 4, characterized in that, The adjustment amount for each parameter is obtained by dividing the allowable adjustment range of each process parameter into equal segments; and determining the adjustment amount for each process parameter based on the segmentation results. The adjustment amount of the guide plate distance of the perforating machine must meet the following formula: ； In the formula, b is the roll gap; l is the guide plate distance of the piercing mill; The diameter of the tube blank; For capillary diameter; b, l, and The units are all mm; The roll speeds of each stand in the reducing mill are calculated using the following formula: ； ； In the formula, Let be the outer diameter of the steel pipe after passing through the i-th frame; Let be the bore diameter of the i-th rack; i is the rack number; x is the current outer diameter deviation; a is the number of racks currently in use. Let be the rotational speed of the i-th rack; Let be the rotational speed of the (i+1)th rack; is the outer diameter of the steel pipe after passing through the (i+1)th frame; s is the wall thickness of the rough pipe; , x The units for both 's' and 's' are mm; and The units are all r / min.

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