Pipe cutting machine laser head groove follow-up control method

Abstract

The invention discloses a pipe cutting machine laser head groove follow-up control method, and relates to the technical field of pipe cutting machines, and the method comprises the following steps: scanning a pipe through a laser head to ensure that the pipe is always positioned on the surface of the pipe in the calibration and calibration process; b-axis zero marking and pendulum length calibration are conducted, it is ensured that a mechanical system and a control system of the pipe cutting machine are in the initial state, and an accurate reference basis is provided for groove treatment; and according to groove calibration data and pipeline parameters, the irradiation angle and power of the laser head are calculated, the following height and the feedback height of the laser head are adjusted, and it is ensured that the laser head keeps the optimal working state in the groove treatment process. Through automatic and accurate control, high quality and high efficiency of groove treatment are achieved, the burden of manual adjustment is reduced, the machining performance of the pipe cutting machine can be remarkably improved, and the pipe cutting machine is widely applied to the field needing high-precision groove treatment.

Description

Technical Field

[0001] The invention relates to the technical field of pipe cutting machines, and in particular to a pipe cutting machine laser head groove follow-up control method. Background Art

[0002] In the field of industrial manufacturing, pipe cutting machine is a kind of equipment widely used for pipe cutting. In the process of pipe cutting, in order to ensure the welding quality of the pipe, it is usually necessary to perform bevel processing on the pipe. When performing bevel processing, traditional pipe cutting machines often use fixed laser heads for irradiation and heating, which makes it difficult to accurately control the angle and shape of the bevel. In addition, when performing bevel processing, traditional pipe cutting machines are easily affected by factors such as pipe materials and thickness, resulting in unstable bevel quality, which further affects the welding quality. 3D laser cutting equipment needs to use bevel tracking control. At different angles and different nozzle shapes and sizes, the sensor distance obtained at the same cutting height is different. Therefore, in order to solve this problem, a bevel tracking control method for the laser head of a pipe cutting machine is proposed.

[0003] Why do we need to calibrate the groove? Because during laser cutting, the capacitance value of the sensor is used to judge the distance from the nozzle at the end of the cutting head to the plate or pipe. When it is 0°, the distance from the nozzle end to the plane is easy to judge. However, when the cutting head rotates to a certain angle, the different shapes and sizes of the nozzles will cause the following height to be not equal to the feedback height. However, what we actually control is the following height. Summary of the invention

[0004] Based on the above-mentioned shortcomings of the prior art, the purpose of the present invention is to provide a pipe cutting machine laser head groove follow-up control method to solve the above-mentioned technical problems.

[0005] To achieve the above object, the present invention provides the following technical solution: a method for controlling the groove of a laser head of a pipe cutting machine, comprising:

[0006] S1: Scan the tube with the laser head to ensure that it is always positioned on the tube surface during the calibration and calibration process;

[0007] S2: Perform B-axis zero mark and pendulum length calibration to ensure that the mechanical system and control system of the pipe cutting machine are in the initial state, providing an accurate reference benchmark for groove processing;

[0008] S3: According to the groove calibration data and pipeline parameters, calculate the irradiation angle and power of the laser head, adjust the follow height and feedback height of the laser head, and ensure that the laser head maintains the best working state during the groove processing.

[0009] The present invention is further configured such that the B-axis zeroing specifically includes: adjusting the angle of the cutting head to 45°, moving the cutting head downward until it touches the surface of the pipe, obtaining the Z-axis height Z1, then adjusting the angle of the cutting head to -45°, moving the cutting head downward until it touches the pipe, obtaining the Z-axis height Z2, obtaining the interpolation ΔZ of the two Z-axis heights of the cutting head at 45° and -45°, when ΔZ is outside the range of -0.06 to 0.06, adjusting the angle of the cutting head, correcting the offset angle by 0.1 each time when the angle deviation is too large, and correcting the offset angle by 0.01 each time when the angle deviation is small, until ΔZ is within the range of -0.06 to 0.06 and the B-axis is vertical, using the groove single-point test program to obtain an oscilloscope graph, and when the two ends of the graph are symmetrical, the calibration of the B-axis zero point is completed.

[0010] The present invention is further configured such that, after the calibration of the B-axis zero point is completed, the pendulum length calibration specifically includes: obtaining a Z-axis coordinate value after the cutting head vertically descends and touches the pipe, and then obtaining a second Z-axis coordinate value after the cutting head is adjusted to 45° and descends and touches the pipe, and the pendulum length L is calculated according to a preset pendulum length calculation formula through the angle and the difference between the two Z-axis coordinate values, wherein the preset pendulum length calculation formula is: L=(ΦD / 2)*tanα*cosα+△z / (1-cosα(, L is the pendulum length, ΦD is the pipe diameter, α is the angle of the cutting head, and △z is the difference between the two Z-axis coordinate values.

[0011] The present invention is further configured that the logic for acquiring the groove calibration data includes:

[0012] Select a fixed length between 2-16mm as the gap G, select 15 consecutive points according to the gap G, adjust the cutting head to 0°, move downward to touch the pipe to measure the Z-axis coordinate to get #206, turn off the cutting head tracking, adjust the cutting head to 45°, and calculate the Z-axis distance between the rtcp point and the actual cutting point;

[0013] Read the gap value after swinging 45°, read the current gap feedback value three times through filtering for 0.15s, and store the average value in the parameter BEVEL_GAP. Calibrate the gap feedback values ​​corresponding to different gaps G through the program loop, and store them in the parameter BEVEL_GAP in turn to complete the calibration.

[0014] The present invention is further configured such that the calculation logic of the Z-axis distance between the rtcp point and the actual cutting point is: #1=#201*sin45°, #2=#206-#201*(1-cos45°), wherein #1 is the horizontal distance, i.e., the horizontal displacement between the point where the cutting head touches the pipe at 0° and the contact point after the cutting head rotates to 45°, #2 is the vertical height of the cutting head after rotating to 45°, #201 is the sum of the pendulum length and the set gap G, and #206 is the Z-axis coordinate of the following height when the cutting head is 0°.

[0015] The present invention is further configured to calculate the irradiation angle and power of the laser head and adjust the follow height and feedback height of the laser head, including:

[0016] Calibrate the sensor in the vertical direction, find the pipe position at 0°, and raise the cutting head to 2mm;

[0017] Rotate the groove angle to 5°;

[0018] Record the actual feedback height at the current position, move 1mm upward along the direction of the cutting head, record the position of the following height and the actual feedback height, and repeat until the following height reaches 15mm;

[0019] Rotate the groove angle to 10°, 15°, 20°, 25°, 30°, 35°, 40°, 45°, -5°, -10°, -15°, -20°, -25°, -30°, -35°, -40°, -45°, and record the position of the following height and the actual feedback height after each rotation.

[0020] The present invention is further configured to obtain a fitting curve according to the relationship between the following height and the actual feedback height: y=y1+(cos(x)-cos(x1)) / (cos(x2)-cos(x1))*(y2-y1), wherein y is the actual following height, y1 is the reference height when 0 degrees, x is the current groove angle, x1 is 0 degrees, x2 is 45 degrees, and y2 is the measured height when 45 degrees. Figure 2 As shown, on the left side you can set the reference height of the benchmark (coordinate position column), set the actual height data of the 45-degree angle (ANGLE 1), and the actual data curve will be displayed on the right side.

[0021] The present invention is further configured to calculate the actual following height according to the obtained fitting curve, set the actual following height as a table, and use the current data of the CNC to calculate the current following height according to the actual groove angle to achieve accurate groove control following.

[0022] The present invention provides a groove follow-up control method for a laser head of a pipe cutting machine. The method scans a pipe by a laser head to ensure that the laser head is always positioned on the surface of the pipe during the calibration and calibration process; performs B-axis zeroing and pendulum length calibration to ensure that the mechanical system and control system of the pipe cutting machine are in an initial state, thereby providing an accurate reference benchmark for groove processing; calculates the irradiation angle and power of the laser head according to groove calibration data and pipeline parameters, adjusts the follow height and feedback height of the laser head, and ensures that the laser head maintains an optimal working state during the groove processing process. The beneficial effects produced include:

[0023] 1. Accurately control the groove angle and follow height: Through multiple calibration steps, especially using the relationship curve between follow height and feedback height, the follow height of the laser head can be adjusted in real time. This method ensures that the laser head always maintains the best working state during the groove processing process, thereby significantly improving the accuracy of the groove angle;

[0024] 2. Improve cutting accuracy and welding quality: The follow-up height of the laser head can be adjusted according to real-time calculations to ensure that the laser head always works at the optimal cutting distance. This can reduce cutting errors, improve the accuracy of groove cutting, and thus improve welding quality, especially in processes with high requirements for welds;

[0025] 3. Adapt to different groove shapes and working conditions: By calibrating the following height at different angles, the laser head can flexibly cope with a variety of groove shapes (such as grooves at different angles and positions), increasing the applicability of the system. Adapting to a variety of pipes and groove types means that the system has broad application prospects in a variety of industrial environments.

[0026] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work. In the drawings:

[0028] Figure 1 A flow chart of a method for controlling the groove of a laser head of a pipe cutting machine according to an exemplary embodiment of the present invention;

[0029] Figure 2 This is an interface diagram showing an implementation method of a laser head groove follow-up control method for a pipe cutting machine according to an exemplary embodiment of the present invention;

[0030] Figure 3 An oscilloscope diagram showing a method for following-up control of a groove of a laser head of a pipe cutting machine after the B-axis zero point is successfully calibrated according to an exemplary embodiment of the present invention;

[0031] Figure 4 A schematic diagram of a follow-up height and a feedback height of a pipe cutting machine laser head groove follow-up control method according to an exemplary embodiment of the present invention;

[0032] Figure 5 A schematic diagram of a groove angle of a method for following-motion control of a groove of a laser head of a pipe cutting machine is shown as an exemplary embodiment of the present invention. DETAILED DESCRIPTION

[0033] The following will describe the embodiments of the present invention with reference to the accompanying drawings and preferred embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the preferred embodiments are only for illustrating the present invention, not for limiting the scope of protection of the present invention.

[0034] It should be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present invention, and thus the drawings only show components related to the present invention rather than being drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed arbitrarily, and the component layout may also be more complicated.

[0035] In the following description, numerous details are discussed to provide a more thorough explanation of the embodiments of the present invention. However, it is obvious to those skilled in the art that the embodiments of the present invention can be implemented without these specific details. In other embodiments, well-known structures and devices are shown in the form of block diagrams rather than in detail to avoid making the embodiments of the present invention difficult to understand.

[0036] A method for controlling the groove of a laser head of a pipe cutting machine Figure 1 As shown, including:

[0037] S1: Scan the tube with the laser head to ensure that it is always positioned on the tube surface during the calibration and calibration process;

[0038] S2: Perform B-axis zero mark and pendulum length calibration to ensure that the mechanical system and control system of the pipe cutting machine are in the initial state, providing an accurate reference benchmark for groove processing;

[0039] S3: According to the groove calibration data and pipeline parameters, calculate the irradiation angle and power of the laser head, adjust the follow height and feedback height of the laser head, and ensure that the laser head maintains the best working state during the groove processing.

[0040] Specifically, first scan the pipe with the laser head to ensure that the calibration and alignment are on the pipe; before performing the groove follow-up control of the laser head of the pipe cutting machine, it is necessary to first perform B-axis zeroing and pendulum length calibration. The purpose of this step is to ensure that the mechanical system and control system of the pipe cutting machine are in the initial state, and prepare for the subsequent groove processing.

[0041] The present invention is further configured such that the B-axis zero mark specifically includes: adjusting the angle of the cutting head to 45°, moving the cutting head downward to touch the surface of the pipe, obtaining the Z-axis height Z1, then adjusting the angle of the cutting head to -45°, moving the cutting head downward to touch the pipe, obtaining the Z-axis height Z2, obtaining the interpolation ΔZ of the Z-axis heights of the cutting head at 45° and -45°, and when ΔZ is outside the range of -0.06 to 0.06, adjusting the angle of the cutting head, correcting the offset angle by 0.1 each time when the angle deviation is too large, and correcting the offset angle by 0.01 each time when the angle deviation is small, until ΔZ is within the range of -0.06 to 0.06 when the B-axis is vertical, using the groove single-point test program to obtain the oscilloscope graph, and when the two ends of the graph are symmetrical, the calibration of the B-axis zero point is completed. Specifically, in the above logic, the core goal is to calibrate the zero point of the B-axis by adjusting the angle and height of the laser cutting head to ensure the accuracy of the laser cutting equipment in groove processing. This logic can be divided into several key steps, each of which aims to adjust the position of the laser head to ensure that the distance between the cutting head and the tube surface is accurate at different angles. Ultimately, this process ensures the vertical state of the B axis and ensures the accuracy of the bevel angle during cutting.

[0042] The present invention is further configured such that after the calibration of the zero point of the B axis is completed, the pendulum length calibration specifically includes: obtaining a Z axis coordinate value after the cutting head vertically descends and touches the pipe, and then adjusting the angle of the cutting head to 45° and descending and touching the pipe to obtain a second Z axis coordinate value, and calculating the pendulum length L according to the preset pendulum length calculation formula through the angle and the difference between the two Z axis coordinate values, wherein the preset pendulum length calculation formula is: L = (ΦD / 2)*tanα*cosα+△z / (1-cosα), L is the pendulum length, ΦD is the pipe diameter, α is the angle of the cutting head, and △z is the difference between the two Z axis coordinate values. Specifically, the core of the above logic is to calibrate the verticality of the B axis and calculate the pendulum length L of the cutting head by adjusting the angle and height of the laser cutting head. Specifically, first, by adjusting the height difference of the cutting head at two angles of 45° and -45°, the precise distance change between the cutting head and the surface of the pipe is obtained, and then the pendulum length L is calculated using geometric relationships and trigonometric functions.

[0043] The present invention is further configured that the logic for acquiring the groove calibration data includes:

[0044] Select a fixed length between 2-16mm as the gap G, select 15 consecutive points according to the gap G, adjust the cutting head to 0°, move downward to touch the pipe to measure the Z-axis coordinate to get #206, turn off the cutting head tracking, adjust the cutting head to 45°, and calculate the Z-axis distance between the rtcp point and the actual cutting point;

[0045] Read the gap value after swinging 45°, read the current gap feedback value 3 times through filtering for 0.15s, and take the average value and store it in the parameter BEVEL_GAP. Calibrate the gap feedback values ​​corresponding to different gaps G through the program loop, and store them in the parameter BEVEL_GAP in turn to complete the calibration. Specifically, the core goal of the above logic is to obtain the groove calibration data through multiple position calibration of the laser cutting head to ensure that the laser head can maintain accurate following height at different groove angles. By selecting a series of fixed points and acquiring data, further filtering and averaging calculations are performed to finally complete the calibration of different gap values ​​G to ensure that the height control of the cutting head at different groove angles is accurate. Figure 3 As shown in the figure, the oscilloscope graph after the B-axis zero point is successfully calibrated is displayed. After the calibration is completed, the calibration result is observed through the oscilloscope to ensure that the B-axis zero point calibration is successful. The waveform graph on the oscilloscope is symmetrical at both ends, indicating that the system has completed the B-axis calibration and the laser head can maintain accurate follow-up height at different angles.

[0046] The present invention is further configured such that the calculation logic of the Z-axis distance between the rtcp point and the actual cutting point is: #1=#201*sin45°, #2=#206-#201*(1-cos45°), wherein #1 is the horizontal distance, i.e., the horizontal displacement between the point where the cutting head touches the pipe at 0° and the point where the cutting head rotates to 45°, #2 is the vertical height of the cutting head after rotating to 45°, #201 is the sum of the pendulum length and the set gap G, and #206 is the Z-axis coordinate of the following height at 0° of the cutting head. Specifically, the core goal of the above logic is to accurately control the height and position of the laser cutting head by calculating the Z-axis distance between the rtcp point and the actual cutting point. The logic is based on the measurement of the pendulum length, gap G, the rotation angle of the laser cutting head (such as 45°), and the Z-axis coordinate, and uses trigonometric functions to calculate the horizontal and vertical displacements of the laser head at different angles. Ultimately, these calculation results are used to optimize the follow-up height control of the laser head during the cutting process.

[0047] like Figure 4 and Figure 5 As shown, the present invention is further configured to calculate the irradiation angle and power of the laser head and adjust the follow height and feedback height of the laser head, including:

[0048] Calibrate the sensor in the vertical direction, find the pipe position at 0°, and raise the cutting head to 2mm;

[0049] Rotate the groove angle to 5°;

[0050] Record the actual feedback height at the current position, move 1mm upward along the direction of the cutting head, record the position of the following height and the actual feedback height, and repeat until the following height reaches 15mm;

[0051] Rotate the groove angle to 10°, 15°, 20°, 25°, 30°, 35°, 40°, 45°, -5°, -10°, -15°, -20°, -25°, -30°, -35°, -40°, -45°, and record the position of the following height and the actual feedback height after each rotation.

[0052] The present invention is further configured to obtain a fitting curve based on the relationship between the following height and the actual feedback height: y=y1+(cos(x)-cos(x1)) / (cos(x2)-cos(x1))*(y2-y1), wherein y is the actual following height, y1 is the reference height at 0 degrees, x is the current groove angle, x1 is 0 degrees, x2 is 45 degrees, and y2 is the measured height at 45 degrees. Specifically, the core goal of the above logic is to adjust the rotation angle of the laser cutting head, record the following height and feedback height at each angle, and gradually obtain a fitting curve to ensure that the laser head can accurately control its following height at different groove angles. This process records the difference between the following height and feedback height of the laser head multiple times, and calculates the actual working height in combination with the fitting of trigonometric functions.

[0053] The present invention is further configured to calculate the actual following height according to the obtained fitting curve, set the actual following height as a table, and use the current data of the CNC to calculate the current following height according to the actual groove angle, so as to achieve accurate control and following of the groove. Specifically, by establishing the fitting curve, the actual following height at each groove angle is calculated, and it is set in the system table for use by the numerical control system (CNC). During the cutting process, the CNC system will automatically adjust the following height of the laser cutting head according to the current groove angle and the data in the table, so as to achieve accurate control of the groove.

[0054] The above embodiments can be implemented in whole or in part by software, hardware, firmware or any other combination. When implemented by software, the above embodiments can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions or computer programs. When the computer instructions or computer programs are loaded or executed on a computer, the process or function described in the embodiment of the present application is generated in whole or in part. 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 computer-readable storage medium. For example, the computer instructions can be transmitted from one website site, computer, server or data center to another website site, computer, server or data center by wired (e.g., infrared, wireless, microwave, etc.). The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that contains one or more available media sets. The available medium can be a magnetic medium (e.g., a floppy disk, a hard disk, a tape), an optical medium (e.g., a DVD), or a semiconductor medium. The semiconductor medium can be a solid-state hard disk.

[0055] It should be understood that the term "and / or" in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. A and B can be singular or plural. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship, but it may also indicate an "and / or" relationship. Please refer to the context for specific understanding.

[0056] In this application, "at least one" means one or more, and "more than one" means two or more. "At least one of the following" or similar expressions refers to any combination of these items, including any combination of single or plural items. For example, at least one of a, b, or c can be represented by: a, b, c, ab, ac, bc, or abc, where a, b, c can be single or multiple.

[0057] It should be understood that in the various embodiments of the present application, the size of the serial numbers of the above-mentioned processes does not mean 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 application.

[0058] Those of ordinary skill in the art will appreciate that the units and algorithm steps of each example 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 performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0059] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0060] In the several embodiments provided in the present application, it should be understood that the disclosed system can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0061] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0062] In addition, each functional unit in each embodiment of the present application 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.

[0063] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application can be essentially or partly embodied in the form of a software product that contributes to the prior art. The computer software product is stored in a storage medium and includes several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the methods described in the various embodiments of the present application. The aforementioned storage media include: various media that can store program codes, such as USB flash drives, mobile hard disks, read-only memories (ROM), random access memories (RAM), magnetic disks or optical disks.

[0064] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A method for controlling the groove of a laser head of a pipe cutting machine, characterized in that: include: S1: Scan the tube with the laser head to ensure that it is always positioned on the tube surface during the calibration and calibration process; S2: Perform B-axis zero mark and pendulum length calibration to ensure that the mechanical system and control system of the pipe cutting machine are in the initial state, providing an accurate reference benchmark for groove processing; S3: According to the groove calibration data and pipeline parameters, calculate the irradiation angle and power of the laser head, adjust the follow height and feedback height of the laser head, and ensure that the laser head maintains the best working state during the groove processing.

2. A method for controlling the groove of a laser head of a pipe cutting machine according to claim 1, characterized in that: The B-axis zeroing specifically includes: adjusting the angle of the cutting head to 45°, moving the cutting head downward until it touches the surface of the pipe, obtaining the Z-axis height Z1, then adjusting the angle of the cutting head to -45°, moving the cutting head downward until it touches the pipe, obtaining the Z-axis height Z2, obtaining the interpolation ΔZ of the two Z-axis heights of the cutting head at 45° and -45°, when ΔZ is outside the range of -0.06 to 0.06, adjusting the angle of the cutting head, when the angle deviation is too large, correcting the offset angle by 0.1 each time, and when the angle deviation is small, correcting the offset angle by 0.01 each time, until ΔZ is within the range of -0.06 to 0.06 and the B-axis is vertical, using the groove single-point test program to obtain an oscilloscope graph, and when the two ends of the graph are symmetrical, the calibration of the B-axis zero point is completed.

3. A pipe cutting machine laser head groove follow-up control method according to claim 1, characterized in that: After completing the calibration of the B-axis zero point, the pendulum length calibration specifically includes: obtaining a Z-axis coordinate value after the cutting head vertically descends and touches the pipe, and then adjusting the angle of the cutting head to 45° and descending to touch the pipe to obtain a second Z-axis coordinate value, and calculating the pendulum length L according to the preset pendulum length calculation formula through the angle and the difference between the two Z-axis coordinate values, wherein the preset pendulum length calculation formula is: L = (ΦD / 2)*tanα*cosα+△z / (1-cosα), L is the pendulum length, ΦD is the pipe diameter, α is the angle of the cutting head, and △z is the difference between the two Z-axis coordinate values.

4. A pipe cutting machine laser head groove follow-up control method according to claim 1, characterized in that: The logic for obtaining groove calibration data includes: Select a fixed length between 2-16mm as the gap G, select 15 consecutive points according to the gap G, adjust the cutting head to 0°, move downward to touch the pipe to measure the Z-axis coordinate to get #206, turn off the cutting head tracking, adjust the cutting head to 45°, and calculate the Z-axis distance between the rtcp point and the actual cutting point; Read the gap value after swinging 45°, read the current gap feedback value three times through filtering for 0.15s, and store the average value in the parameter BEVEL_GAP. Calibrate the gap feedback values ​​corresponding to different gaps G through the program loop, and store them in the parameter BEVEL_GAP in turn to complete the calibration.

5. A pipe cutting machine laser head groove follow-up control method according to claim 4, characterized in that: The calculation logic of the Z-axis distance between the rtcp point and the actual cutting point is: #1=#201*sin45°, #2=#206-#201*(1-cos45°), where #1 is the horizontal distance, that is, the horizontal displacement from the point where the cutting head touches the pipe at 0° to the contact point after the cutting head rotates to 45°, #2 is the vertical height of the cutting head after it rotates to 45°, #201 is the sum of the pendulum length and the set gap G, and #206 is the Z-axis coordinate of the following height when the cutting head is 0°.

6. A method for controlling the groove of a laser head of a pipe cutting machine according to claim 1, characterized in that: Calculate the irradiation angle and power of the laser head, and adjust the following height and feedback height of the laser head, including: Calibrate the sensor in the vertical direction, find the pipe position at 0°, and raise the cutting head to 2mm; Rotate the groove angle to 5°; Record the actual feedback height at the current position, move 1mm upward along the direction of the cutting head, record the position of the following height and the actual feedback height, and repeat until the following height reaches 15mm; Rotate the groove angle to 10°, 15°, 20°, 25°, 30°, 35°, 40°, 45°, -5°, -10°, -15°, -20°, -25°, -30°, -35°, -40°, -45°, and record the position of the following height and the actual feedback height after each rotation.

7. A pipe cutting machine laser head groove follow-up control method according to claim 6, characterized in that: The fitting curve is obtained according to the relationship between the following height and the actual feedback height: y=y1+(cos(x)-cos(x1)) / (cos(x2)-cos(x1))*(y2-y1), where y is the actual following height, y1 is the reference height at 0 degrees, x is the current groove angle, x1 is 0 degrees, x2 is 45 degrees, and y2 is the measured height at 45 degrees.

8. A method for controlling the groove of a laser head of a pipe cutting machine according to claim 7, characterized in that: The actual following height is calculated based on the obtained fitting curve, and the actual following height is set in a table. The CNC uses the current data to calculate the current following height according to the actual groove angle to achieve accurate groove control following.

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