A production control method for ultra-thin-walled steel pipes

Abstract

This invention discloses a production control method for ultra-thin-walled steel pipes, including obtaining first specification parameters of a solid round billet and second specification parameters of the finished steel pipe; sawing the solid round billet according to the second specification parameters to form short round billets; feeding the short round billets into an annular furnace, and sequentially passing through a heat recovery section, a preheating section, a preheating section, a heating section (sections one to four), and a soaking section for heating; monitoring the temperature of the short round billets in real time to ensure that the center temperature of the short round billets reaches a first temperature threshold. The first adjustment refers to the initial adjustment of the burner temperature based on the analysis results of the first image, used to address anomalies in the surface temperature of the short round billets; the second adjustment refers to the secondary adjustment of the burner temperature based on the analysis results of the second image, used to address anomalies in both the surface and internal temperatures of the short round billets, which helps to eliminate local non-uniformity in the temperature field of the short round billets on the surface and inside.

Description

Technical Field

[0001] This invention relates to the technical field of steel pipe production, and in particular to a production control method for ultra-thin-walled steel pipes. Background Technology

[0002] Ultra-thin-walled steel pipes refer to steel pipe products where the ratio of wall thickness to outer diameter reaches an extremely small value. They have advantages such as light weight, high material utilization, and good heat transfer performance, and are widely used in high-end manufacturing fields such as aerospace, petrochemicals, automobile manufacturing, and energy equipment. Due to the extremely thin wall thickness of ultra-thin-walled steel pipes, the temperature control precision requirements during hot rolling production are extremely high. Even slight temperature fluctuations can lead to quality problems such as uneven wall thickness, surface cracks, and dimensional deviations.

[0003] Currently, the hot rolling production process of seamless steel pipes typically includes major steps such as billet heating, piercing, continuous rolling, and sizing. In the billet heating stage, a ring furnace is commonly used to heat the solid round billet to a suitable plastic deformation temperature. However, in existing heating control methods, the temperature control of each heating section in the annular furnace is relatively independent, lacking real-time monitoring and regulation of the overall temperature field of the billet. Moreover, it mainly relies on thermocouples to measure the furnace temperature and adjusts the furnace temperature by controlling the gas flow of the burners. However, this method cannot directly obtain the temperature distribution inside the billet. Due to the influence of factors such as the thermal conductivity, geometric dimensions, and position of the billet in the furnace, there are often large temperature differences between the surface and center of the billet and different parts. This temperature non-uniformity will directly affect the processing quality of subsequent piercing and continuous rolling processes, resulting in uneven wall thickness or dimensional deviations. Before the piercing mill and sizing mill, the billet will experience a temperature drop during the conveying process. Currently, fixed heating parameters are usually used, which fail to dynamically adjust according to the actual temperature state of the billet, resulting in insufficient heating or overheating. Especially for ultra-thin-walled steel pipes, the temperature control deviation will be amplified into wall thickness deviation, affecting product quality. Summary of the Invention

[0004] The technical problems solved by this invention are: 1. In existing heating control methods, the temperature control of each heating section in the ring furnace is relatively independent, lacking real-time monitoring and regulation of the overall temperature field of the billet; 2. Without considering the internal temperature distribution of the billet, there are often large temperature differences between different parts. This temperature inhomogeneity directly affects the processing quality of subsequent piercing and continuous rolling processes, resulting in uneven wall thickness or dimensional deviations; 3. Using fixed heating parameters without dynamic adjustment according to the actual temperature state of the billet leads to insufficient heating or overheating. Especially for ultra-thin-walled steel pipes, temperature control deviations are amplified into wall thickness deviations, affecting product quality.

[0005] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a production control method for ultra-thin-walled steel pipes, comprising: Step S1: Obtain the first specification parameters of the solid round tube blank and the second specification parameters of the finished steel pipe, and cut the solid round tube blank into short round blanks according to the second specification parameters; Step S2: The short billet is fed into the ring furnace and is heated in sequence through the heat recovery section, the first preheating section, the second preheating section, the first to fourth heating sections and the soaking section. The temperature of the short billet is monitored in real time to ensure that the center temperature of the short billet reaches the first temperature threshold. Step S3: After the heated short billet is conveyed to the piercing mill for a first heating and temperature compensation, the temperature of the billet is raised to the second temperature threshold and then pierced to obtain a tube. Then the tube is subjected to borax treatment, continuous rolling treatment and rod removal treatment to obtain a steel pipe. Step S4: The steel pipe is transported to the sizing machine and subjected to secondary heating to raise the temperature of the steel pipe to the third temperature threshold. The steel pipe is then sizing to obtain the finished steel pipe and cooled.

[0006] As a preferred embodiment of the production control method for ultra-thin-walled steel pipes described in this invention, step S1 specifically includes: Step S11: Organize all the first specification parameters of the steel pipes into a parameter table in advance, match the first specification parameters with the second specification parameters as the first correspondence, and mark the corresponding processing parameters according to the second specification parameters. Step S12: The first specification parameters include length range, radius range and steel type; the second specification parameters include length, inner diameter, outer diameter, pipe wall thickness and steel type. The geometric model of the solid round tube blank is obtained by laser scanning, and the length and radius of the solid round tube blank are obtained. The steel type of the solid round tube blank is manually labeled. Step S13: The solid round tube blank is sawn according to the length in the second specification parameter to form a short round blank, and the geometric model of the solid round tube blank is also divided according to the same length to form a short round blank model.

[0007] As a preferred embodiment of the production control method for the ultra-thin-walled steel pipe described in this invention, the first temperature threshold includes the center temperature threshold of the short round billet in the processing parameters corresponding to the first preheating stage, the second preheating stage, the first to fourth heating stages, and the homogenization stage.

[0008] As a preferred embodiment of the production control method for ultra-thin-walled steel pipes described in this invention, step S2 specifically includes: Step S21: Set a temperature acquisition module on the side of the short material round billet, and use the temperature acquisition module to collect the temperature information of the short material round billet. The temperature acquisition module is an array of infrared thermometers distributed on both sides of the short material round billet, and each infrared thermometer is numbered. Step S22: Use the synchronization signal transmitter to send detection commands to each infrared thermometer. Each infrared thermometer receives the detection commands, feeds back the current temperature information of the short round billet, and records the feedback time point, as well as the number and location of the infrared thermometer in real time. Step S23: Map each temperature information onto the short material round billet model, and use different color values ​​to represent different temperature gradients to form the temperature field of the short material round billet model; Step S24: Add the thermal conductivity of the short billet and the heating source of the ring furnace to the short billet model, and set the position and temperature of the heating source to be the same as the burner of the ring furnace, and set the corresponding radiation model and boundary conditions to simulate the heating process of the short billet. Step S25: Monitor the heating process of the short billet and adjust the temperature of each burner.

[0009] As a preferred embodiment of the production control method for ultra-thin-walled steel pipes described in this invention, step S25 specifically includes: Step S251: Take a screenshot of the temperature field of the short material round billet model to obtain a first image, and divide the first image into regions according to different colors. According to the correspondence between color and temperature gradient, obtain the temperature information corresponding to each color, extract the region where the temperature information is greater than the temperature fluctuation threshold, and determine whether the region where the temperature information is greater than the temperature fluctuation threshold is a high temperature region or a low temperature region. If the temperature information of this area is less than the average temperature in the first image, it indicates that this area is a low-temperature area; If the temperature information of this area is greater than the average temperature in the first image, it indicates that this area is a high-temperature zone; Step S252: Adjust the burner temperature, including: If the area is a low-temperature zone, increase the opening of the gas valve of the burner closest to the area to increase the burner temperature; If the area is a high-temperature zone, reduce the gas valve opening of the burner closest to the area to lower the burner temperature; Step S252: According to the preset time interval and distance interval, slice the temperature field of the short material round billet model to obtain the second image of the short material round billet model, and divide the second image into regions according to different colors to obtain the temperature information corresponding to each color, extract the region where the temperature information is greater than the temperature fluctuation threshold, and determine whether the region where the temperature information is greater than the temperature fluctuation threshold is a high temperature region or a low temperature region. If the temperature information of this area is less than the average temperature in the second image, it indicates that this area is a low-temperature area; If the temperature information of this area is greater than the average temperature in the second image, it indicates that this area is a high-temperature zone; Step S252: Perform secondary adjustment of the burner temperature, including: If the area is a low-temperature zone, and the corresponding area in the first image is also a low-temperature zone, then increase the gas valve opening of the burner closest to that area to increase the burner temperature; If the area is a low-temperature zone and the corresponding area in the first image is a high-temperature zone, then maintain the gas valve opening of the burner; If the area is a high-temperature zone and the corresponding area in the first image is a low-temperature zone, then increase the gas valve opening of the burner closest to that area to increase the burner temperature; If the area is a high-temperature zone, and the corresponding area in the first image is also a high-temperature zone, then reduce the gas valve opening of the burner closest to that area to lower the burner temperature.

[0010] As a preferred embodiment of the production control method for the ultra-thin-walled steel pipe described in this invention, step S26: retrieve the center temperature thresholds corresponding to the first preheating stage, the second preheating stage, the first to fourth heating stages, and the homogenization stage respectively, and collect the temperature information of the short round billet in the first preheating stage, the second preheating stage, the first to fourth heating stages, and the homogenization stage in real time. Step S27: Calculate the heating time required for the center temperature of the short blank to reach the center temperature threshold.

[0011] As a preferred embodiment of the production control method for ultra-thin-walled steel pipes described in this invention, step S27 specifically includes: The mathematical expression for the Biot number is:

[0012] Where Bi represents the Biwoe number, h represents the thermal conductivity, L represents the radius of the short billet, and λ represents the thermal conductivity. The center temperature ratio is calculated based on the center temperature thresholds corresponding to the first preheating stage, the second preheating stage, the first to fourth heating stages, or the soaking stage, or the temperature information of the short billet. Its mathematical expression is:

[0013] in, Indicates heating time, Indicates the center temperature ratio, Indicates the temperature of the heating medium, This indicates the center temperature threshold that the short round billet needs to reach. This represents the temperature information of the short round billet at the first time point when heating begins. The heating time is calculated from this first time point. The heating time is determined by referring to the Heisler plot based on the Biot number and the center temperature ratio. The horizontal axis of the Heisler plot represents the Biot number, and the vertical axis represents the center temperature ratio. The corresponding Fourier number is found on the Heisler plot, and then the heating time is calculated. The calculation expression is as follows:

[0014] in, denoted by Fourier number, a by thermal diffusivity, and L by radius of the short round blank.

[0015] As a preferred embodiment of the production control method for the ultra-thin-walled steel pipe described in this invention, wherein: Step S3 includes: Step S31: Set up a set of temperature acquisition modules and medium frequency induction heating equipment in front of the piercing machine, and acquire the first real-time temperature information of the short round billet in front of the piercing machine through the temperature acquisition modules; Step S32: Calculate the heating time based on the first real-time temperature information and the second temperature threshold, and perform a heating compensation on the short material round blank based on the calculated heating time; Step S33: After the short round billet has been heated and reheated once, a piercing process is performed, and the temperature information of the short round billet during the piercing process is collected in real time. If the temperature of the short billet is less than the preset fourth temperature threshold, the power of the medium-frequency induction heating equipment will be increased. If the temperature of the short billet is higher than the set fourth temperature threshold, the power of the medium-frequency induction heating equipment will be reduced. Step S34: The short round blank is pierced to obtain a tube.

[0016] As a preferred embodiment of the production control method for the ultra-thin-walled steel pipe described in this invention, the borax treatment includes borax blowing onto the inner surface of the tube, with the blowing volume controlled at 120-150 kg per square meter. The continuous rolling process includes feeding the tube into a three-roll six-stand continuous rolling mill, using a mandrel for cyclic limited-motion rolling, preheating the mandrel to a first temperature range, and gradually increasing the hardness of the continuous rolling roll surface from a first hardness value to a second hardness value. The stripping process involves stripping the steel rods using a three-roller, three-stand stripping machine to obtain the steel pipe.

[0017] As a preferred embodiment of the production control method for ultra-thin-walled steel pipes described in this invention, step S4 includes: Step S41: Set up a set of temperature acquisition modules and medium frequency induction heating equipment in front of the sizing machine, and acquire the second real-time temperature information of the steel pipe in front of the sizing machine through the temperature acquisition modules; Step S42: Calculate the heating time based on the second real-time temperature information and the third temperature threshold, and perform secondary heating to compensate for the temperature of the steel pipe based on the calculated heating time; Step S43: The steel pipe after secondary heating and temperature compensation is fed into a three-roll sizing machine for micro-tension sizing to obtain the finished steel pipe; Step S45: Place the finished steel pipe into a cooling bed for slow cooling.

[0018] The beneficial effects of this invention are as follows: 1. By identifying temperature anomaly areas through image analysis and making a comprehensive judgment based on the results of two consecutive detections, the burner temperature is controlled. The first adjustment refers to the initial adjustment of the burner temperature based on the analysis results of the first image, which is used to adjust the burner temperature according to the anomaly of the surface temperature of the short material round billet. The second adjustment refers to the second adjustment of the burner temperature based on the analysis results of the second image, which is used to adjust the burner temperature according to the anomalies of the surface and internal temperature of the short material round billet. This helps to eliminate the local non-uniformity of the temperature field on the surface and inside of the short material round billet. Compared with the traditional method that only relies on furnace temperature control, it can directly monitor the temperature distribution on the surface and inside of the short material round billet and make targeted adjustments according to the type of temperature anomaly, which helps to improve the heating uniformity.

[0019] 2. By calculating the heating time, it is possible to ensure that the temperature at the center of the short round billet reaches the center temperature threshold, avoiding the problems of insufficient heating or overheating. This is beneficial to improving production efficiency and product quality, and can minimize the risk of insufficient or excessive heating. In production, overheating is generally used to prevent insufficient heating, but this method can reduce overheating and help save energy.

[0020] 3. By installing a medium-frequency induction heating device before the piercing mill, the temperature of the short round billet is compensated, ensuring that the piercing process is carried out under optimal temperature conditions, thereby improving piercing quality and the dimensional accuracy of the tube. The process parameters for borax treatment, continuous rolling treatment, and rod removal treatment have been optimized to adapt to the deformation characteristics of ultra-thin-walled steel tubes, ensuring the stability and wall thickness uniformity of the continuous rolling process. Attached Figure Description

[0021] Figure 1 This is a basic flowchart illustrating a production control method for ultra-thin-walled steel pipes provided in one embodiment of the present invention. Detailed Implementation

[0022] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0023] Example 1, referring to Figure 1As an embodiment of the present invention, a production control method for ultra-thin-walled steel pipes is provided, comprising: including: Step S1: Obtain the first specification parameters of the solid round tube blank and the second specification parameters of the finished steel pipe, and cut the solid round tube blank into short round blanks according to the second specification parameters; Step S2: The short billet is fed into the annular furnace and sequentially passes through the heat recovery section, the first preheating section, the second preheating section, the first to fourth heating sections, and the soaking section for heating. The temperature of the short billet is monitored in real time to ensure that the center temperature of the short billet reaches the first temperature threshold. The billet temperature is monitored in real time during the heating process in the annular furnace to ensure that the center temperature reaches the set threshold. Step S3: After the heated short round billet is conveyed to the piercing mill for a first heating and temperature compensation, the temperature of the billet is raised to the second temperature threshold and then pierced to obtain a rough tube. Then, the rough tube is subjected to borax treatment, continuous rolling treatment and rod removal treatment to obtain a steel pipe. By optimizing the process parameters of borax treatment, continuous rolling treatment and rod removal treatment, the deformation characteristics of the ultra-thin-walled steel pipe are adapted, ensuring the stability of the continuous rolling process and the uniformity of wall thickness, and improving the quality consistency of the finished steel pipe.

[0024] Step S4: The steel pipe is conveyed to the sizing machine and subjected to secondary heating to raise its temperature to the third temperature threshold. The pipe is then sizing to obtain the finished steel pipe, which is then cooled. Precise heating is performed before piercing and sizing to ensure the processing temperature requirements of each step are met.

[0025] In practice, by collecting temperature data of short-material round billets in real time, constructing temperature information of short-material round billets, and constructing the temperature field of short-material round billet models, it is possible to grasp the surface temperature distribution and internal temperature distribution of short-material round billets. By identifying abnormal areas in the surface temperature distribution and internal temperature distribution of short-material round billets and adjusting the burner temperature, it is beneficial to eliminate local non-uniformity of the temperature field and ensure the uniformity of heating of short-material round billets.

[0026] Furthermore, a set of temperature acquisition modules and medium-frequency induction heating equipment are set up in front of the piercing mill and sizing mill respectively. The temperature is supplemented according to the actual temperature state of the short material round billet to ensure that the surface temperature of the short material round billet is uniform. This allows the piercing mill and sizing mill to operate under optimal temperature conditions, which helps to reduce quality problems such as uneven wall thickness or dimensional deviation caused by uneven temperature in the production of ultra-thin-walled steel pipes.

[0027] Example 2 is another embodiment of the present invention. This embodiment differs from the first embodiment in that step S1 specifically includes: Step S11: Organize all the first specification parameters of the steel pipes into a parameter table in advance, match the first specification parameters with the second specification parameters as the first correspondence, and mark the corresponding processing parameters according to the second specification parameters; the first specification parameters are a set of parameters describing the original state of the solid round tube blank, used to identify the initial geometric features and material information of the tube blank, and provide basic data for subsequent sawing and temperature control.

[0028] In this invention, the first specification parameter is read from the production management system by the parameter acquisition module or obtained manually. After data format conversion, it is stored in the database and mapped to the second specification parameter to guide the parameter settings for sawing and subsequent processes. The first correspondence is the mapping relationship between the first and second specification parameters, used to establish the correspondence rules between the specifications of the solid round billet and the specifications of the finished steel pipe. In one embodiment, the first correspondence is stored in the database in the form of a data table. Each record contains the specification range of the solid round billet and the corresponding range of finished steel pipe specifications, as well as the corresponding processing parameters. The processing parameters include process parameters such as temperature threshold, heating time, and rolling speed for each process.

[0029] Step S12: The first specification parameters include the length range, radius range and steel type; the second specification parameters include the length, inner diameter, outer diameter, pipe wall thickness and steel type. The geometric model of the solid round tube blank is obtained by laser scanning, and the length and radius of the solid round tube blank are obtained. The steel type of the solid round tube blank is manually marked. In this invention, the length range refers to the allowable range of the length of the solid round tube blank, usually measured in millimeters, used to determine whether the solid round tube blank meets production requirements; the radius range refers to the allowable range of the radius of the solid round tube blank, used to determine the size grade of the solid round tube blank; the steel grade refers to the material grade of the solid round tube blank, such as 20#, 45#, Q345, etc., used to determine the thermophysical parameters and processing parameters of the solid round tube blank; the second specification parameter is a set of parameters describing the target state of the finished steel pipe, used to define the geometric dimensions and material requirements of the final product. A method for obtaining the three-dimensional coordinates of an object's surface using existing laser measurement technology is used to establish a digital geometric model of the solid round tube blank. In one embodiment, a laser scanning device is set in the solid round tube blank loading area. When the solid round tube blank is transported to the scanning station, the laser scanning device scans the surface of the solid round tube blank, obtaining point cloud data of the solid round tube blank surface, and generating a geometric model of the solid round tube blank after data processing.

[0030] Furthermore, manual labeling involves operators inputting the billet steel type via a human-machine interface to supplement material information that laser scanning cannot obtain. In one embodiment, when loading the billet, the operator scans the label on the billet with a barcode scanner or manually inputs the steel type, and the system associates and stores the steel type with the geometric model.

[0031] Furthermore, the thin-walled varieties include: steel pipes with an outer diameter of 114mm ≤ D < 152mm and a wall thickness of 4.5-7mm when the bore type is 191; When the aperture is 235, the steel pipe has an outer diameter of 168mm ≤ D ≤ 219mm and a wall thickness of 5-6.5mm; When the bore type is 292, the steel pipe has an outer diameter of 229mm ≤ D ≤ 279mm and a wall thickness of 5.4-6.5mm.

[0032] Step S13: The solid round tube blank is sawn according to the length specified in the second specification parameter to form a short round blank. The geometric model of the solid round tube blank is also divided into short round blank models according to the same length. The geometric model of the solid round tube blank is stored in the form of a three-dimensional mesh model, containing geometric information such as the length, radius, and cylindricity of the tube blank. Through the geometric model, the length and radius of the solid round tube blank can be accurately obtained, providing accurate dimensional basis for sawing.

[0033] In this invention, the second specification parameter is issued by the production planning system to the parameter acquisition module. After being matched with the first specification parameter, it is used to calculate the sawing length and determine the process parameters for each step. Here, length is the target length of the finished steel pipe; inner diameter is the inner diameter of the finished steel pipe; outer diameter is the outer diameter of the finished steel pipe; wall thickness is the wall thickness of the finished steel pipe; for extremely thin-walled steel pipes, the ratio of wall thickness to outer diameter is typically less than 0.05; and steel grade is the material grade of the finished steel pipe, which matches the steel grade of the solid round tube blank.

[0034] Furthermore, the sawing equipment employs a band saw or circular saw, and performs fixed-length sawing on the solid round tube billet based on the sawing length calculated by the parameter acquisition module. The calculation of the sawing length takes into account the length of the finished steel pipe, the metal consumption coefficient of each process, and sawing loss. The short round billets obtained after sawing are used for subsequent ring furnace heating and piercing processing. The length of the short round billets is determined according to the specifications of the finished steel pipe, typically between 1.5 meters and 4 meters. The short round billet model is a digital model obtained by dividing the geometric model of the solid round tube billet according to the sawing length, and is used for subsequent temperature field simulation and control. The short round billet model corresponds one-to-one with the actual short round billet, and each short round billet model contains the geometric information, material information, and positional information of the short round billet, providing geometric boundary conditions for temperature field simulation.

[0035] By establishing parameter tables and geometric models, digital management of billet specifications was achieved, providing a data foundation for subsequent temperature field simulation and control. By establishing the correspondence between the first specification parameter and the second specification parameter, automatic matching of processing parameters was realized, reducing manual intervention and improving production efficiency.

[0036] The first temperature threshold includes the center temperature threshold of the short round billet in the processing parameters corresponding to the first preheating stage, the second preheating stage, the first to fourth heating stages, and the homogenization stage.

[0037] Step S2 specifically includes: A ring furnace is a continuous heating device used to heat metal billets. Its furnace chamber is arranged in a ring shape, and the billet rotates and moves on the furnace bottom, passing through each heating section in sequence. In this invention, the ring furnace includes eight heating sections: a heat recovery section, a preheating section, a preheating section, a heating section, a heating section, a heating section, a heating section, a heating section, a heating section, and a soaking section. Each heating section is equipped with several burners, which generate heat by burning gas to heat the short round billet.

[0038] The heat recovery section utilizes waste heat from the flue gas to preheat the short billets just entering the furnace, improving energy efficiency. Preheating sections one and two involve gradual preheating of the short billets, typically at temperatures between 400℃ and 700℃. Heating sections one through four involve rapid heating of the short billets, typically at temperatures between 800℃ and 1200℃. The homogenization section aims to homogenize the temperature inside and outside the short billets, typically at temperatures between 1150℃ and 1250℃.

[0039] The first temperature threshold is the target center temperature value that the short round billet needs to reach in each heating section, used to determine whether the heating is sufficient. In this invention, the first temperature threshold includes the center temperature thresholds corresponding to the first preheating section, the second preheating section, the first to fourth heating sections, and the soaking section. The center temperature threshold for each heating section is determined according to the steel type and finished product specifications.

[0040] Step S21: A temperature acquisition module is installed on the side of the short billet to collect its temperature information. The temperature acquisition module is an array of infrared thermometers distributed on both sides of the short billet, and each infrared thermometer is numbered. The temperature acquisition module is used to collect the surface temperature of the short billet by combining infrared thermometers to obtain temperature distribution data of the billet surface. In this invention, the temperature acquisition module is an array of infrared thermometers distributed on both sides of the short billet. Each infrared thermometer is fixed to the outside of the annular furnace wall by a bracket, and the temperature probe passes through a temperature measuring hole on the furnace wall and is aimed at the surface of the short billet.

[0041] Step S22: A synchronization signal transmitter sends detection commands to each infrared thermometer. Each infrared thermometer receives the detection commands, returns the current temperature information of the short-material round billet, and records the feedback time point, as well as the number and location of the infrared thermometer in real time. In this invention, the infrared thermometer array is arranged along the circumference and axial direction of the ring furnace, covering the entire heating area of ​​the short-material round billet. Each infrared thermometer has a unique number to identify its location information. The synchronization signal transmitter sends detection commands to all infrared thermometers simultaneously to ensure that each thermometer collects temperature data synchronously. The synchronization signal transmitter connects to each infrared thermometer via wired or wireless means and sends detection commands at preset time intervals (e.g., once per second). The detection command includes timestamp information to identify the detection time. Temperature information includes temperature value, measurement time, infrared thermometer number, and measurement location coordinates. The feedback time point is the moment when the infrared thermometer returns temperature data, used to determine the time point of the temperature data.

[0042] Step S23: Map each temperature information onto the short billet model and use different color values ​​to represent different temperature gradients to form the temperature field of the short billet model; In this invention, the temperature field is a collection of temperature distributions at various points inside the short round billet, used to describe the temperature distribution state of the billet. The temperature field is displayed on the monitoring interface as a three-dimensional color image, with different colors representing different temperature values, forming an intuitive visualization of the temperature distribution. The temperature gradient is the degree to which temperature changes with spatial location, used to characterize the uniformity of the temperature distribution. The temperature gradient is calculated by the temperature difference between adjacent temperature measurement points; a larger temperature gradient indicates a more uneven temperature distribution. The correspondence between color values ​​and temperature gradients is a rule for mapping temperature values ​​to color values, used to achieve the visualization of the temperature field. Preferably, a color mapping scheme commonly used in thermal imaging is adopted, with low-temperature areas displayed as blue or green, high-temperature areas as yellow or red, and intermediate temperatures as orange.

[0043] Step S24: Add the thermal conductivity of the short billet and the heating source of the ring furnace to the short billet model, and set the position and temperature of the heating source to be the same as the burner of the ring furnace, and set the corresponding radiation model and boundary conditions to simulate the heating process of the short billet. In this invention, thermal conductivity is the material's ability to conduct heat and is used to calculate the temperature distribution inside the billet. The thermal conductivity is obtained from a material database based on the steel grade of the short billet, and it varies with temperature; in the simulation, it is calculated using variable physical property parameters. The heating source is the burner in the annular furnace that generates heat to heat the short billet. In this invention, the location and temperature of the heating source correspond one-to-one with the actual burners in the annular furnace, and the temperature of each heating source is acquired in real time by a temperature acquisition module or set by a control system. The radiation model is a mathematical model describing heat transfer through radiation, used to calculate the radiative heat transfer between the burner and the billet. The radiation model preferably uses the zone method or Monte Carlo method, considering multiple radiative heat transfers between the burner flame, furnace wall, and billet. Boundary conditions are the physical conditions on the boundaries of the simulation model, used to determine the constraints for the simulation calculation. Boundary conditions include parameters such as the convective heat transfer coefficient, radiative heat transfer coefficient, and furnace temperature distribution on the billet surface. Simulation is the process of solving the billet temperature field using numerical calculation methods to predict the temperature distribution inside the billet. The simulation is preferably performed using the finite element method or the finite difference method to solve the unsteady heat conduction equation and obtain the temperature change of each point inside the tube blank over time.

[0044] Step S25: Monitor the heating process of the short-material round billet and adjust the temperature of each burner. Step S25 specifically includes: Step S251: Take a screenshot of the temperature field of the short round billet model to obtain the first image, and divide the first image into regions according to different colors. According to the correspondence between color and temperature gradient, obtain the temperature information corresponding to each color, extract the region where the temperature information is greater than the temperature fluctuation threshold, and determine whether the region where the temperature information is greater than the temperature fluctuation threshold is a high temperature region or a low temperature region. The first image is a screenshot of the temperature field at a certain moment, which is used to analyze the temperature distribution state at that moment.

[0045] In this invention, the first image is stored in color image format. Each pixel in the image corresponds to a position on the short round billet model, and the color value of the pixel corresponds to the temperature value at that position. Region segmentation is a process of dividing the first image according to color to identify the boundaries of different temperature regions. Region segmentation preferably uses image segmentation algorithms, such as threshold segmentation or clustering segmentation, to divide the image into several regions with similar temperatures. The temperature fluctuation threshold is a critical value for judging whether the temperature is abnormal and is used to identify temperature abnormal regions. The temperature fluctuation threshold is preferably set according to process requirements, typically ±10℃ to ±20℃ of the target temperature. When the temperature deviation of a certain region from the target temperature exceeds the temperature fluctuation threshold, the region is determined to be a temperature abnormal region.

[0046] If the temperature information of this area is less than the average temperature in the first image, it indicates that this area is a low-temperature area; If the temperature information of this area is greater than the average temperature in the first image, it indicates that this area is a high-temperature zone; Step S252: Adjust the burner temperature, including: If the area is a low-temperature zone, increase the gas valve opening of the burner closest to the area to raise the burner temperature. The amount of reduction in the gas valve opening is determined by the size of the temperature deviation. The larger the temperature deviation, the larger the reduction in opening; the smaller the temperature deviation, the smaller the increase in opening.

[0047] If the area is a high-temperature zone, reduce the gas valve opening of the burner closest to the area to lower the burner temperature; the first adjustment is based on the analysis results of the first image and is used to make an initial adjustment to the burner temperature according to the abnormal surface temperature of the short material round billet.

[0048] Step S252: According to the preset time interval and distance interval, slice the temperature field of the short material round billet model to obtain the second image of the short material round billet model, and divide the second image into regions according to different colors to obtain the temperature information corresponding to each color. Extract the regions where the temperature information is greater than the temperature fluctuation threshold, and determine whether the regions where the temperature information is greater than the temperature fluctuation threshold are high temperature regions or low temperature regions. After a certain time interval, take another temperature field screenshot to evaluate the effect of the first adjustment.

[0049] In this invention, the time interval is determined based on the thermal response time of the tube blank, typically ranging from 30 seconds to 2 minutes. The distance interval is the slicing spacing along the axial or circumferential direction of the tube blank, used to obtain the temperature distribution at different locations on the tube blank.

[0050] If the temperature information of this area is less than the average temperature in the second image, it indicates that this area is a low-temperature area; If the temperature information of this area is greater than the average temperature in the second image, it indicates that this area is a high-temperature zone; Step S252: Perform secondary adjustment of the burner temperature, including: If the area is a low-temperature zone, and the corresponding area in the first image is also a low-temperature zone, then increase the gas valve opening of the burner closest to that area to increase the burner temperature; If the area is a low-temperature zone and the corresponding area in the first image is a high-temperature zone, then maintain the gas valve opening of the burner; If the area is a high-temperature zone and the corresponding area in the first image is a low-temperature zone, then increase the gas valve opening of the burner closest to that area to increase the burner temperature; If the area is a high-temperature zone, and the corresponding area in the first image is also a high-temperature zone, then reduce the gas valve opening of the burner closest to that area to lower the burner temperature.

[0051] By identifying abnormal temperature areas through image analysis and combining the results of two consecutive detections, the burner temperature is controlled. The first adjustment is based on the analysis results of the first image, used to make an initial adjustment to the burner temperature according to the abnormal surface temperature of the short billet. The second adjustment is based on the analysis results of the second image, used to make a second adjustment to the burner temperature according to the abnormal surface and internal temperature of the short billet. This helps to eliminate local non-uniformity of the temperature field on the surface and inside of the short billet. Compared with traditional methods that rely solely on furnace temperature control, this method can directly monitor the temperature distribution on the surface and inside of the short billet and make targeted adjustments according to the type of temperature abnormality. This helps to improve heating uniformity and avoid underheating or overheating. In production, overheating is generally used to prevent underheating, but this method can reduce overheating and save energy.

[0052] Step S26: Retrieve the center temperature thresholds corresponding to the first preheating stage, the second preheating stage, the first to fourth heating stages, and the soaking stage respectively, and collect the temperature information of the short material round billet in the first preheating stage, the second preheating stage, the first to fourth heating stages, and the soaking stage in real time; the center temperature threshold is the target center temperature value that the short material round billet needs to reach in each heating stage, which is used to determine whether the heating is sufficient.

[0053] In this invention, the center temperature threshold is retrieved from the process parameter database based on the steel type and finished product specifications. For example, for 20# steel, the center temperature threshold for the first preheating stage is approximately 400°C, for the second preheating stage it is approximately 600°C, for the first heating stage it is approximately 800°C, for the second heating stage it is approximately 950°C, for the third heating stage it is approximately 1100°C, for the fourth heating stage it is approximately 1200°C, and for the soaking stage it is approximately 1230°C.

[0054] Step S27: Calculate the heating time required for the center temperature of the short round billet to reach the center temperature threshold. Step S27 specifically includes: The mathematical expression for the Biot number is:

[0055] Where Bi represents the Biwoe number, h represents the thermal conductivity, L represents the radius of the short billet, and λ represents the thermal conductivity. The center temperature ratio is calculated based on the center temperature thresholds corresponding to the first preheating stage, the second preheating stage, the first to fourth heating stages, or the soaking stage, or the temperature information of the short billet. Its mathematical expression is:

[0056] Among them, among them, Indicates heating time, Indicates the center temperature ratio, Indicates the temperature of the heating medium, This indicates the center temperature threshold that the short round billet needs to reach. This represents the temperature information of the short round billet at the first time point when heating begins. The heating time is calculated from this first time point. The heating time is determined by referring to the Heisler plot based on the Biot number and the center temperature ratio. The horizontal axis of the Heisler plot represents the Biot number, and the vertical axis represents the center temperature ratio. The corresponding Fourier number is found on the Heisler plot, and then the heating time is calculated. The calculation expression is as follows:

[0057] in, denoted by Fourier number, a by thermal diffusivity, and L by radius of the short round blank.

[0058] In this invention, the convective heat transfer coefficient h represents the intensity of convective heat transfer between the fluid and the solid surface, and is related to factors such as the airflow velocity in the furnace, the furnace gas composition, and the surface condition of the tube blank. The convective heat transfer coefficient is determined based on the operating conditions of the annular furnace, typically ranging from 50 to 200 W / (m²·K). The thermal conductivity is obtained from a material database, and considering the influence of temperature on the thermal conductivity, an interpolation method is used to calculate the thermal conductivity value at the current temperature. For example, the thermal conductivity of 20# steel is approximately 30 W / (m·K) at 800℃ and approximately 25 W / (m·K) at 1200℃. The heating medium temperature T∞ is the gas temperature inside the furnace, obtained by thermocouple measurement. The temperature of the heating medium is determined according to the set temperature of each heating section, and is usually 50°C to 150°C higher than the target temperature of the billet. The corresponding Fourier number is obtained by referring to the Heisler plot based on the Biot number and the center temperature ratio. The Heisler plot is a dimensionless graph used to solve unsteady heat conduction problems, and the Fourier number is a dimensionless time characterizing the unsteady heat conduction process, used to describe the degree of heat penetration into an object. By calculating the heating time, it is possible to ensure that the temperature at the center of the short billet reaches the center temperature threshold, avoiding the problems of insufficient heating or overheating, which is beneficial to improving production efficiency and product quality.

[0059] Step S3 includes: Step S31: Set up a set of temperature acquisition modules and medium frequency induction heating equipment in front of the piercing mill. The temperature acquisition modules collect the first real-time temperature information of the short round billet in front of the piercing mill. The piercing mill is a rolling equipment used to pierce solid round billets into hollow tubes. It is a key process in the production of hot-rolled seamless steel pipes.

[0060] In this invention, the piercing mill is a two-roll skew rolling piercing mill or a three-roll piercing mill. Two or three inclined rolls rotate and move the billet forward, while the mandrel pierces a hole in the center of the billet. The medium-frequency induction heating equipment uses an alternating magnetic field generated by a medium-frequency current to induction heat the metal, and is used for rapid temperature replenishment of the tube billet. In this invention, the frequency range of the medium-frequency induction heating equipment is 500Hz to 2500Hz, and the power range is 500kW to 2000kW. It can raise the surface temperature of the tube billet by 50°C to 150°C in a short time. The first real-time temperature information is collected in real time by a temperature acquisition module at a frequency of 1 to 10 times per second. The second temperature threshold is the target temperature value of the tube billet required for the piercing process, used to ensure piercing quality. The second temperature threshold is determined according to the steel type; for carbon steel, it is typically 1200°C to 1280°C, and for alloy steel, it is typically 1150°C to 1250°C.

[0061] Step S32: Calculate the heating time based on the first real-time temperature information and the second temperature threshold. Perform a heating compensation on the short blank based on the calculated heating time. The calculation method for the heating time is the same as that for step S27. In one embodiment, if the time to move to the piercing machine is very short, the heating time can be omitted, and only the surface of the short blank can be heated to reach the second temperature threshold.

[0062] Step S33: After the short round billet has been heated and reheated once, a piercing process is performed, and the temperature information of the short round billet during the piercing process is collected in real time. If the temperature of the short billet is less than the preset fourth temperature threshold, the power of the medium-frequency induction heating equipment will be increased. In this invention, the piercing process is completed on a piercing mill. The short billet rotates and moves forward under the action of the rolls, and the mandrel pierces a hole in the center of the billet to form a tube. The fourth temperature threshold is the lower limit of the billet temperature during the piercing process, used to ensure piercing quality. The fourth temperature threshold is determined according to the steel grade and is usually 20°C to 50°C lower than the second temperature threshold. If the temperature of the short billet is lower than the fourth temperature threshold, defects such as inward folding and outward folding may occur during the piercing process.

[0063] Real-time temperature acquisition is an operation that continuously monitors the billet temperature during the piercing process to promptly detect temperature anomalies. In this invention, the temperature acquisition module is located at the inlet and outlet of the piercing mill to collect the surface temperature of the billet in real time. Step S34: The short round blank is pierced to obtain a tube.

[0064] Borax treatment involves borax blowing onto the inner surface of the capillary tubes, with the blowing volume controlled at 120-150 kg per square meter; In this invention, borax treatment is a process of blowing borax onto the inner surface of the mandrel to improve lubrication conditions during continuous rolling. Nitrogen gas is used as the carrier gas to blow borax powder into the inner hole of the mandrel. The borax melts at high temperature to form a lubricating film, reducing friction between the mandrel and the inner surface of the mandrel. The amount of borax blown is controlled at 120-150 kg per square meter. Too little blown amount will result in insufficient lubrication, while too much blown amount will cause waste and environmental pollution.

[0065] The continuous rolling process includes feeding the tube into a three-roll six-stand continuous rolling mill, using a mandrel for cyclic limited-motion rolling, preheating the mandrel to the first temperature range, and gradually increasing the hardness of the continuous rolling roll surface from the first hardness value to the second hardness value. In this invention, continuous rolling is a process of continuously rolling a tube into a continuous rolling mill to reduce its wall thickness and extend its length. The continuous rolling process uses a three-roll, six-stand continuous rolling mill, with three rolls arranged at 120° intervals in each stand, and the six stands connected in series. A mandrel is inserted into the tube, and under the action of the rolls, the wall thickness is reduced, the outer diameter decreases, and the length is extended. The mandrel is a tool used to support the inner hole of the tube and control the inner diameter during rolling; it is a key component of the continuous rolling process. The mandrel operates in a cyclic, limited-movement mode, meaning that the mandrel moves at a speed lower than that of the tube during rolling, and is withdrawn from the tube after rolling and returned to the inlet side for reuse. The mandrel is preheated to a first temperature range, typically 100°C to 200°C. Preheating aims to reduce the temperature difference between the mandrel and the tube, preventing thermal cracks on the mandrel surface. The surface hardness of the continuous rolling rolls is the hardness value of the working surface of the rolls, affecting the wear resistance and rolling quality of the rolls. The surface hardness of the rolling mill rolls gradually increases from a first hardness value to a second hardness value. The first hardness value is typically HRC55 to HRC60, and the second hardness value is typically HRC60 to HRC65. The purpose of gradually increasing the surface hardness of the rolls is to accommodate the decrease in hardness caused by the increase in roll temperature during rolling, and to maintain the stability of the rolling process.

[0066] The stripping process involves stripping the steel rods using a three-roll, three-stand stripping machine to obtain the steel pipe.

[0067] In this invention, the mandrel removal process is the process of extracting the mandrel from the tube to complete the continuous rolling process. The mandrel removal process uses a three-roll, three-stand tube removal mill. The tube passes through the mill, and the mandrel is pulled out by a clamping mechanism. After mandrel removal, a steel tube is obtained, and the wall thickness of the steel tube is close to the finished product requirements. By setting up a medium-frequency induction heating device before the piercing mill, the temperature of the short round billet is compensated, ensuring that the piercing process is carried out under optimal temperature conditions, improving piercing quality and tube dimensional accuracy. The process parameters for borax treatment, continuous rolling, and mandrel removal are optimized to adapt to the deformation characteristics of the ultra-thin-walled steel tube, ensuring the stability and wall thickness uniformity of the continuous rolling process.

[0068] Step S4: The steel pipe is transported to the sizing machine and subjected to secondary heating to raise the temperature of the steel pipe to the third temperature threshold. The steel pipe is then sizing to obtain the finished steel pipe and cooled.

[0069] The calculation method for the secondary heating and temperature compensation time in this invention is the same as that in step S27, except that the radius L representing the short billet is replaced by the wall thickness of the steel pipe. The medium-frequency induction heating time is calculated based on the billet's temperature rise requirement, inductor power, and heating efficiency. Since the steel pipe wall is very thin, the internal temperature of the steel pipe can be calculated without further calculation; sizing can be performed directly after the surface temperature reaches the third temperature threshold. The sizing mill is a rolling mill used to precisely sizing the outer diameter of steel pipes, ensuring the dimensional accuracy of the finished steel pipe. In this invention, the sizing mill is a three-roll sizing mill with multiple stands arranged in series, each stand having three rolls arranged at 120° intervals.

[0070] Step S41: Set up a set of temperature acquisition modules and medium frequency induction heating equipment in front of the sizing machine, and collect the second real-time temperature information of the steel pipe in front of the sizing machine through the temperature acquisition modules; Step S42: Calculate the heating time based on the second real-time temperature information and the third temperature threshold, and perform secondary heating to compensate for the temperature of the steel pipe based on the calculated heating time; the third temperature threshold is the target temperature value of the steel pipe required by the sizing process, which is used to ensure the sizing quality.

[0071] In this invention, the third temperature threshold is determined based on the steel type. For carbon steel, it is typically 800°C to 950°C, and for alloy steel, it is typically 750°C to 900°C. Excessive sizing temperature leads to severe oxidation, while insufficient temperature makes sizing difficult. Secondary heating compensation utilizes medium-frequency induction heating equipment to compensate for temperature drops during continuous rolling and conveying. The goal of secondary heating compensation is to raise the steel pipe temperature to the third temperature threshold, with a compensation range typically between 50°C and 150°C.

[0072] Step S43: The steel pipe after secondary heating and temperature compensation is fed into a three-roll sizing machine for micro-tension sizing to obtain the finished steel pipe; micro-tension sizing is a sizing process carried out under slight tension to control the outer diameter and wall thickness accuracy of the steel pipe.

[0073] In this invention, micro-tension sizing is achieved by controlling the rolling speed of each stand, with the speed of each subsequent stand slightly higher than that of the previous stand, generating slight tension to keep the steel pipe straight during the sizing process. The finished steel pipe is the steel pipe that has reached the final size requirements after sizing and is used for subsequent cooling and finishing processes. In this invention, the outer diameter tolerance of the finished steel pipe is controlled within ±0.5%, and the wall thickness tolerance is controlled within ±5%.

[0074] Step S45: Place the finished steel pipe into a cooling bed for slow cooling. A cooling bed is a device used to slowly cool hot-rolled steel pipes to avoid thermal and structural stresses caused by rapid cooling.

[0075] In this invention, the cooling bed adopts a stepping or chain structure, and the steel pipe moves slowly on the cooling bed, gradually cooling to room temperature through natural convection and radiation. Slow cooling is a cooling method that controls the cooling rate to reduce residual stress in the steel pipe. In one embodiment, the slow cooling rate is controlled between 5°C and 20°C per minute to avoid structural stress and deformation caused by excessively rapid cooling.

[0076] By performing secondary heating and temperature compensation before the sizing machine, the steel pipe is ensured to reach a suitable temperature during the sizing process, effectively controlling the dimensional accuracy of the finished steel pipe. Slow cooling avoids thermal stress and structural stress caused by rapid cooling, eliminates temperature drop defects during the transportation process, helps reduce the deformation resistance of the steel pipe, improves its plasticity, and ensures its quality. Compared with the traditional method of using fixed parameter control, dynamic temperature compensation based on the actual temperature state of the steel pipe improves the accuracy of temperature control and reduces dimensional deviations caused by temperature fluctuations.

[0077] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, 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 storage medium can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as Static Random Access Memory (SRAM), Electrically Erasable Programmable Read-Only Memory (EEPROM), Erasable Programmable Read Only Memory (EPROM), Programmable Red-Only Memory (PROM), Read-Only Memory (ROM), magnetic storage, flash memory, magnetic disk, or optical disk. These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function 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 1One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0078] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A production control method for ultra-thin-walled steel pipes, characterized in that, include: Step S1: Obtain the first specification parameters of the solid round tube blank and the second specification parameters of the finished steel pipe, and cut the solid round tube blank into short round blanks according to the second specification parameters; Step S2: The short billet is fed into the ring furnace and is heated in sequence through the heat recovery section, the first preheating section, the second preheating section, the first to fourth heating sections and the soaking section. The temperature of the short billet is monitored in real time to ensure that the center temperature of the short billet reaches the first temperature threshold. Step S3: After the heated short billet is conveyed to the piercing mill for a first heating and temperature compensation, the temperature of the billet is raised to the second temperature threshold and then pierced to obtain a tube. Then the tube is subjected to borax treatment, continuous rolling treatment and rod removal treatment to obtain a steel pipe. Step S4: The steel pipe is transported to the sizing machine and subjected to secondary heating to raise the temperature of the steel pipe to the third temperature threshold. The steel pipe is then sizing to obtain the finished steel pipe and cooled.

2. The production control method for ultra-thin-walled steel pipes as described in claim 1, characterized in that: Step S1 specifically includes: Step S11: Organize all the first specification parameters of the steel pipes into a parameter table in advance, match the first specification parameters with the second specification parameters as the first correspondence, and mark the corresponding processing parameters according to the second specification parameters. Step S12: The first specification parameters include length range, radius range and steel type; the second specification parameters include length, inner diameter, outer diameter, pipe wall thickness and steel type. The geometric model of the solid round tube blank is obtained by laser scanning, and the length and radius of the solid round tube blank are obtained. The steel type of the solid round tube blank is manually labeled. Step S13: The solid round tube blank is sawn according to the length in the second specification parameter to form a short round blank, and the geometric model of the solid round tube blank is also divided according to the same length to form a short round blank model.

3. The production control method for ultra-thin-walled steel pipes as described in claim 2, characterized in that: The first temperature threshold includes the center temperature threshold of the short round blank in the processing parameters corresponding to the first preheating stage, the second preheating stage, the first to fourth heating stages, and the homogenization stage.

4. The production control method for ultra-thin-walled steel pipes as described in claim 3, characterized in that: Step S2 specifically includes: Step S21: Set a temperature acquisition module on the side of the short material round billet, and use the temperature acquisition module to collect the temperature information of the short material round billet. The temperature acquisition module is an array of infrared thermometers distributed on both sides of the short material round billet, and each infrared thermometer is numbered. Step S22: Use the synchronization signal transmitter to send detection commands to each infrared thermometer. Each infrared thermometer receives the detection commands, feeds back the current temperature information of the short round billet, and records the feedback time point, as well as the number and location of the infrared thermometer in real time. Step S23: Map each temperature information onto the short material round billet model, and use different color values ​​to represent different temperature gradients to form the temperature field of the short material round billet model; Step S24: Add the thermal conductivity of the short billet and the heating source of the ring furnace to the short billet model, and set the position and temperature of the heating source to be the same as the burner of the ring furnace, and set the corresponding radiation model and boundary conditions to simulate the heating process of the short billet. Step S25: Monitor the heating process of the short billet and adjust the temperature of each burner.

5. The production control method for ultra-thin-walled steel pipes as described in claim 4, characterized in that: Step S25 specifically includes: Step S251: Take a screenshot of the temperature field of the short material round billet model to obtain a first image, and divide the first image into regions according to different colors. According to the correspondence between color and temperature gradient, obtain the temperature information corresponding to each color, extract the region where the temperature information is greater than the temperature fluctuation threshold, and determine whether the region where the temperature information is greater than the temperature fluctuation threshold is a high temperature region or a low temperature region. If the temperature information of this area is less than the average temperature in the first image, it indicates that this area is a low-temperature area; If the temperature information of this area is greater than the average temperature in the first image, it indicates that this area is a high-temperature zone; Step S252: Adjust the burner temperature, including: If the area is a low-temperature zone, increase the opening of the gas valve of the burner closest to the area to increase the burner temperature; If the area is a high-temperature zone, reduce the gas valve opening of the burner closest to the area to lower the burner temperature; Step S252: According to the preset time interval and distance interval, slice the temperature field of the short material round billet model to obtain the second image of the short material round billet model, and divide the second image into regions according to different colors to obtain the temperature information corresponding to each color, extract the region where the temperature information is greater than the temperature fluctuation threshold, and determine whether the region where the temperature information is greater than the temperature fluctuation threshold is a high temperature region or a low temperature region. If the temperature information of this area is less than the average temperature in the second image, it indicates that this area is a low-temperature zone; If the temperature information of this area is greater than the average temperature in the second image, it indicates that this area is a high-temperature zone; Step S252: Perform secondary adjustment of the burner temperature, including: If the area is a low-temperature zone, and the corresponding area in the first image is also a low-temperature zone, then increase the gas valve opening of the burner closest to that area to increase the burner temperature; If the area is a low-temperature zone and the corresponding area in the first image is a high-temperature zone, then maintain the gas valve opening of the burner; If the area is a high-temperature zone and the corresponding area in the first image is a low-temperature zone, then increase the gas valve opening of the burner closest to that area to increase the burner temperature; If the area is a high-temperature zone, and the corresponding area in the first image is also a high-temperature zone, then reduce the gas valve opening of the burner closest to that area to lower the burner temperature.

6. The production control method for ultra-thin-walled steel pipes as described in claim 4, characterized in that: Step S26: Retrieve the center temperature thresholds corresponding to the first preheating stage, the second preheating stage, the first to fourth heating stages, and the homogenization stage respectively, and collect the temperature information of the short round billet in the first preheating stage, the second preheating stage, the first to fourth heating stages, and the homogenization stage in real time; Step S27: Calculate the heating time required for the center temperature of the short blank to reach the center temperature threshold.

7. The production control method for ultra-thin-walled steel pipes as described in claim 6, characterized in that: Step S27 specifically includes: The mathematical expression for the Biot number is: ； Where Bi represents the Biwoe number, h represents the thermal conductivity, L represents the radius of the short billet, and λ represents the thermal conductivity. The center temperature ratio is calculated based on the center temperature thresholds corresponding to the first preheating stage, the second preheating stage, the first to fourth heating stages, or the soaking stage, or the temperature information of the short billet. Its mathematical expression is: ； in, Indicates heating time, Indicates the center temperature ratio, Indicates the temperature of the heating medium, This indicates the center temperature threshold that the short round billet needs to reach. This represents the temperature information of the short round billet at the first time point when heating begins. The heating time is calculated from this first time point. The heating time is determined by referring to the Heisler plot based on the Biot number and the center temperature ratio. The horizontal axis of the Heisler plot represents the Biot number, and the vertical axis represents the center temperature ratio. The corresponding Fourier number is found on the Heisler plot, and then the heating time is calculated. The calculation expression is as follows: ； in, denoted by Fourier number, a by thermal diffusivity, and L by radius of the short round blank.

8. The production control method for ultra-thin-walled steel pipes as described in claim 7, characterized in that: Step S3 includes: Step S31: Set up a set of temperature acquisition modules and medium frequency induction heating equipment in front of the piercing machine, and acquire the first real-time temperature information of the short round billet in front of the piercing machine through the temperature acquisition modules; Step S32: Calculate the heating time based on the first real-time temperature information and the second temperature threshold, and perform a heating compensation on the short material round blank based on the calculated heating time; Step S33: After the short round billet has been heated and reheated once, a piercing process is performed, and the temperature information of the short round billet during the piercing process is collected in real time. If the temperature of the short billet is less than the preset fourth temperature threshold, the power of the medium-frequency induction heating equipment will be increased. If the temperature of the short billet is higher than the set fourth temperature threshold, the power of the medium-frequency induction heating equipment will be reduced. Step S34: The short round blank is pierced to obtain a tube.

9. The production control method for ultra-thin-walled steel pipes as described in claim 8, characterized in that: The borax treatment includes borax blowing onto the inner surface of the capillary tube, with the blowing volume controlled at 120-150 kg per square meter; The continuous rolling process includes feeding the tube into a three-roll six-stand continuous rolling mill, using a mandrel for cyclic limited-motion rolling, preheating the mandrel to a first temperature range, and gradually increasing the hardness of the continuous rolling roll surface from a first hardness value to a second hardness value. The stripping process involves stripping the steel rods using a three-roller, three-stand stripping machine to obtain the steel pipe.

10. The production control method for ultra-thin-walled steel pipes as described in claim 9, characterized in that: Step S4 includes: Step S41: Set up a set of temperature acquisition modules and medium frequency induction heating equipment in front of the sizing machine, and acquire the second real-time temperature information of the steel pipe in front of the sizing machine through the temperature acquisition modules; Step S42: Calculate the heating time based on the second real-time temperature information and the third temperature threshold, and perform secondary heating to compensate for the temperature of the steel pipe based on the calculated heating time; Step S43: The steel pipe after secondary heating and temperature compensation is fed into a three-roll sizing machine for micro-tension sizing to obtain the finished steel pipe; Step S45: Place the finished steel pipe into a cooling bed for slow cooling.

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