A bevel servo control method for a laser head of a pipe cutting machine

Abstract

The application discloses a kind of laser head bevel servo control methods of pipe cutting machine, it is related to the technical field of pipe cutting machine, the method includes: by laser head is scanned to pipe, ensure that always be positioned in the surface of pipe during calibration and calibration process;B-axis zero mark and swing length calibration are carried out, ensure that the mechanical system and control system of pipe cutting machine are in initial state, provide accurate reference datum for bevel processing;According to bevel calibration data and pipe parameter, the irradiation angle and power of laser head are calculated, the following height and feedback height of laser head are adjusted, ensure that laser head maintains optimum working condition during bevel processing process.By automation and accurate control, high quality, high efficiency of bevel processing are realized, and the burden of manual adjustment is reduced, can significantly improve the machining performance of pipe cutting machine, and is widely applied in the field needing high-precision bevel processing.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of pipe cutting machine, in particular to a pipe cutting machine laser head groove servo control method. BACKGROUND

[0002] In the field of industrial manufacturing, pipe cutting machine is a device widely used in pipe cutting. In the process of pipe cutting, in order to ensure the welding quality of pipe, it is usually necessary to carry out groove processing on the pipe. When carrying out groove processing, the traditional pipe cutting machine often uses fixed laser head to irradiate and heat, so that the angle and shape of the groove are difficult to control accurately. In addition, when carrying out groove processing, the traditional pipe cutting machine is easily affected by factors such as pipe material and thickness, resulting in unstable groove quality, which further affects the welding quality. The 3D laser cutting equipment needs to use groove servo control. Under different angles and different nozzle shapes and sizes, the sensor distance obtained by the same cutting height is different. Therefore, in order to solve this problem, a pipe cutting machine laser head groove servo control method is proposed.

[0003] Why calibrate the groove: because when laser cutting, the capacitance value of the sensor is used as the judgment of the distance from the nozzle at the end of the cutting head to the plate or pipe material. When 0°, the distance from the nozzle end to the plane is good to judge, but when the cutting head rotates a certain angle, the different shapes and sizes of the nozzle will cause the following height not to be equal to the feedback height, but we actually control the following height. SUMMARY

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

[0005] To achieve the above-mentioned purpose, the present application provides the following technical scheme: a pipe cutting machine laser head groove servo control method, comprising:

[0006] S1: scanning the pipe material by the laser head to ensure that it is always positioned on the surface of the pipe material during the calibration and calibration process;

[0007] S2: zero mark and swing length calibration of B axis are carried out to ensure that the mechanical system and control system of the pipe cutting machine are in the initial state, and to provide accurate reference datum for groove processing;

[0008] S3: according to the groove calibration data and pipe parameters, the irradiation angle and power of the laser head are calculated, the following height and feedback height of the laser head are adjusted, and the best working state of the laser head in the groove processing process is ensured.

[0009] The application is further provided with the B-axis zero-point calibration, which specifically comprises: adjusting the angle of the cutting head to 45°, moving the cutting head downward to touch the surface of the pipe to obtain the Z-axis height Z1, adjusting the angle of the cutting head to -45°, moving the cutting head downward to touch the pipe to obtain the Z-axis height Z2, obtaining the difference ΔZ of the Z-axis height of the cutting head at 45° and -45°, adjusting the angle of the cutting head when ΔZ is out of the range of -0.06-0.06, correcting the offset angle of 0.1 each time when the angle offset is too large, correcting the offset angle of 0.01 each time when the angle offset is small, until the B-axis is vertical when ΔZ is in the range of -0.06-0.06, obtaining the oscilloscope pattern by using the single-point test program of the bevel, and completing the calibration of the B-axis zero-point when the pattern is symmetrical at both ends.

[0010] The application is further provided with the B-axis zero-point calibration, which specifically comprises: adjusting the angle of the cutting head to 45°, moving the cutting head downward to touch the surface of the pipe to obtain the Z-axis height Z1, adjusting the angle of the cutting head to -45°, moving the cutting head downward to touch the pipe to obtain the Z-axis height Z2, obtaining the difference ΔZ of the Z-axis height of the cutting head at 45° and -45°, adjusting the angle of the cutting head when ΔZ is out of the range of -0.06-0.06, correcting the offset angle of 0.1 each time when the angle offset is too large, correcting the offset angle of 0.01 each time when the angle offset is small, until the B-axis is vertical when ΔZ is in the range of -0.06-0.06, obtaining the oscilloscope pattern by using the single-point test program of the bevel, and completing the calibration of the B-axis zero-point when the pattern is symmetrical at both ends. , is the length of the pendulum, is the diameter of the pipe, is the angle of the cutting head, is the difference of the Z-axis coordinate values.

[0011] The application is further provided with the acquisition logic of the bevel calibration data, which comprises:

[0012] selecting a fixed length as the gap G between 2-16 mm, selecting 15 consecutive points according to the gap G, adjusting the cutting head to 0°, moving downward to touch the pipe to measure the Z-axis coordinate to obtain #206, closing the cutting head, adjusting the cutting head to 45°, and calculating the Z-axis distance between the rtcp point and the actual cutting point;

[0013] reading the gap value after swinging through 45°, reading the current gap feedback value for 3 times through filtering 0.15 s, taking the average value and storing it in the parameter BEVEL_GAP, calibrating the gap feedback values corresponding to different gaps G through program loop, and storing them in the parameter BEVEL_GAP in turn to complete the calibration.

[0014] ​The application is further provided 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, that is, the horizontal displacement between the point of touching the pipe at 0° of the cutting head and the touch point after the cutting head is rotated to 45°, #2 is the vertical height of the cutting head after being rotated 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 at 0°.

[0015] The application is further provided that the irradiation angle and power of the laser head are calculated, and the following height and feedback height of the laser head are adjusted, comprising:

[0016] The sensor in the vertical direction is calibrated, the pipe position is found in the 0° case, the cutting head is raised to the position of 2 mm, and the following height and the actual feedback height are recorded.

[0017] The bevel angle is rotated to 5°.

[0018] The actual feedback height of the current position is recorded, the cutting head is moved upward by 1 mm along the direction of the cutting head, the following height and the actual feedback height are recorded, and the process is repeated until the following height reaches 15 mm.

[0019] The bevel angle is rotated to 10°, 15°, 20°, 25°, 30°, 35°, 40°, 45°, -5°, -10°, -15°, -20°, -25°, -30°, -35°, -40°, and -45°, and the following height and the actual feedback height are recorded after each rotation.

[0020] The application is further provided that a fitting curve is obtained according to the relationship between the following height and the actual feedback height. , wherein, is the actual following height, is the reference height at 0°, is the current bevel angle, is 0°, is 45°, is the measured height at 45°, as shown in Figure 2 , the reference height (coordinate position column) can be set on the left side, the actual height data (ANGLE 1) of 45° angle is set, and the actual data curve is displayed on the right side.

[0021] The application is further provided that the actual following height is calculated according to the obtained fitting curve, the actual following height is set as a table, the current data is used by the CNC to calculate the current following height according to the actual bevel angle, and the accurate control following of the bevel is realized.

[0022] The present application provides a kind of laser head groove servo control method of pipe cutting machine, the method is scanned to pipe by laser head, ensure that it is always positioned on the surface of pipe during calibration and calibration process;B axis zero mark and swing length calibration are carried out, ensure that the mechanical system and control system of pipe cutting machine are in initial state, provide accurate reference datum for groove processing;According to the groove calibration data and pipe parameters, the irradiation angle and power of laser head are calculated, the following height of laser head is adjusted, and the beneficial effects include:

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

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

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

[0026] The above description is only a summary of the technical solutions of the present application, in order to more clearly understand the technical means of the present application, which can be implemented according to the content of the specification, and in order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the following specific embodiments of the present application are described. BRIEF DESCRIPTION OF DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings needed in the embodiment description. Obviously, the drawings in the following description are only some embodiments of the present application, and those skilled in the art can obtain other drawings according to these drawings without creating any creative labor.In the drawings:

[0028] Figure 1 A flow chart of a groove servo control method of laser head of pipe cutting machine is shown for an exemplary embodiment of the present application;

[0029] Figure 2An implementation interface diagram of a bevel following control method of a laser head of a pipe cutting machine is shown for an exemplary embodiment of the present application;

[0030] Figure 3 An oscilloscope diagram after successful calibration of B-axis zero point of a bevel following control method of a laser head of a pipe cutting machine is shown for an exemplary embodiment of the present application;

[0031] Figure 4 A diagram of following height and feedback height of a bevel following control method of a laser head of a pipe cutting machine is shown for an exemplary embodiment of the present application;

[0032] Figure 5 A diagram of bevel angle of a bevel following control method of a laser head of a pipe cutting machine is shown for an exemplary embodiment of the present application. DETAILED DESCRIPTION

[0033] Other advantages and effects of the present application can be easily understood by those skilled in the art from the above description of the preferred embodiments. The present application can also be implemented or applied in other different specific embodiments, and the details in the specification can be modified or changed based on different views and applications without departing from the spirit of the present application. It should be understood that the preferred embodiments are only for illustrating the present application, but not for limiting the protection scope of the present application.

[0034] It should be noted that the diagrams provided in the following embodiments only schematically illustrate the basic concept of the present application, and only the components related to the present application are shown in the diagrams, but not the number, shape and size of the components when actually implemented. The type, number and proportion of the components when actually implemented can be arbitrarily changed, and the layout type of the components can also be more complex.

[0035] In the following description, a large number of details are discussed to provide a more thorough explanation of the embodiments of the present application, however, it is obvious to those skilled in the art that the embodiments of the present application can be implemented without these specific details, and in other embodiments, the known structures and devices are shown in the form of block diagrams instead of details, to avoid making the embodiments of the present application difficult to understand.

[0036] A bevel following control method of a laser head of a pipe cutting machine, as shown in Figure 1 includes:

[0037] S1: scanning the pipe by the laser head to ensure that the pipe surface is always positioned during the calibration and calibration process;

[0038] S2: Perform B-axis zero calibration and swing length calibration to ensure that the mechanical system and control system of the pipe cutting machine are in the initial state, and provide accurate reference for the bevel processing;

[0039] S3: According to the bevel calibration data and the pipe parameters, the irradiation angle and power of the laser head are calculated, and the following height and feedback height of the laser head are adjusted to ensure that the laser head maintains the best working state during the bevel processing.

[0040] Specifically, first, the laser head is used to scan the pipe to ensure that the calibration and calibration processes can be performed on the pipe. Before performing the bevel follow-up control of the laser head of the pipe cutting machine, B-axis zero calibration and swing length calibration are first performed. 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 to prepare for subsequent bevel processing.

[0041] The present application further provides that the B-axis zero calibration specifically includes: adjusting the angle of the cutting head to 45°, moving the cutting head downward to touch the pipe surface to obtain the Z-axis height Z1, then adjusting the angle of the cutting head to -45°, moving the cutting head downward to touch the pipe to obtain the Z-axis height Z2, obtaining the difference ΔZ between the two Z-axis heights when the cutting head is at 45° and -45°, when ΔZ is outside the range of -0.06~0.06, adjusting the angle of the cutting head, when the angle deviation is too large, correcting the offset angle by 0.1 each time, when the angle deviation is small, correcting the offset angle by 0.01 each time, until ΔZ is within the range of -0.06~0.06, the B-axis is vertical, and the oscilloscope pattern is obtained using the bevel single-point test program. When the pattern is symmetrical at both ends, the calibration of the B-axis zero point is completed. Specifically, in the above logic, the core objective 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 during bevel processing. This logic can be divided into several key steps, each step aims to adjust the position of the laser head to ensure that the distance between the cutting head and the pipe surface is accurate at different angles. Finally, through this process, the vertical state of the B-axis is ensured, and the accuracy of the bevel angle during cutting is guaranteed.

[0042] The present application further provides that after completing the calibration of the B-axis zero point, the swing length calibration specifically includes: obtaining a Z-axis coordinate value when the cutting head is vertically lowered to touch the pipe, then adjusting the angle of the cutting head to 45° and lowering it to touch the pipe to obtain a second Z-axis coordinate value, calculating the swing length according to a preset swing length calculation formula through the difference between the angle and the two Z-axis coordinate values , wherein the preset swing length calculation formula is: , is the swing length, is the diameter of the pipe, is the angle of the cutting head, The difference between the two Z-axis coordinate values is G. Specifically, the core of the above logic is to calibrate the perpendicularity of the B-axis and calculate the swing 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 45° and -45°, the precise distance change between the cutting head and the pipe surface is obtained, and then the swing length L is calculated using geometric relationships and trigonometric functions.

[0043] The application further provides that the acquisition logic of the bevel calibration data comprises:

[0044] Select a fixed length as the gap G between 2-16mm, select 15 consecutive points according to the gap G, adjust the cutting head to 0°, move it down to touch the pipe and measure the Z-axis coordinate to get #206, turn off the cutting head, 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 through 45°, read the current gap feedback value 3 times through filtering 0.15s, take the average value and store it in the parameter BEVEL_GAP, calibrate the gap feedback value corresponding to different gaps G through program loop, and store it in the parameter BEVEL_GAP in turn to complete the calibration. Specifically, the core goal of the above logic is to obtain bevel calibration data through multiple position calibration of the laser cutting head, and ensure that the laser head can maintain accurate follow-up height under different bevel angles. By selecting a series of fixed points and obtaining data, further filtering and average value calculation are performed to finally complete the calibration of different gap values G, ensuring that the height control of the cutting head under different bevel angles is accurate. As shown in Figure 3 The oscilloscope diagram after successful calibration of the B-axis zero point is shown in FIG. 8. After calibration, the calibration result is observed through the oscilloscope to ensure that the B-axis zero point calibration is successful. The waveform diagram 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 application is further configured 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, that is, the horizontal displacement between the point of touching the pipe at 0° of the cutting head and the touch point after the cutting head is rotated to 45°, #2 is the vertical height of the cutting head after being rotated 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 at 0°. Specifically, the above logic core target 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, the gap G, the rotation angle (such as 45°) of the laser cutting head and the Z-axis coordinate, and the horizontal and vertical displacements of the laser head at different angles are calculated by using trigonometric functions. Finally, these calculation results are used to optimize the servo height control of the laser head in the cutting process.

[0047] As shown in Figure 4 and Figure 5 The application is further configured to calculate the irradiation angle and power of the laser head, and adjust the following height and feedback height of the laser head, including:

[0048] Calibrate the sensor in the vertical direction, find the position of the pipe material under the condition of 0°, and raise the cutting head to a position of 2mm;

[0049] Rotate the bevel angle to 5°;

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

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

[0052] The application is further configured that a fitting curve is obtained according to the relationship between the following height and the actual feedback height: , wherein, is the actual following height, is the reference height at 0°, is the current bevel angle, is 0°, is 45°, The height is measured when the angle is 45 degrees. Specifically, the core objective of the above logic is to record the follow-up height and feedback height at each angle by adjusting the rotation angle of the laser cutting head, and gradually obtain a fitting curve to ensure that the laser head can accurately control its follow-up height at different bevel angles. The actual working height is obtained by recording the difference between the follow-up height and the feedback height of the laser head multiple times and combining the fitting calculation of the trigonometric function.

[0053] The application further provides that the actual follow-up height is calculated according to the obtained fitting curve, and the actual follow-up height is set in a table, and the CNC calculates the current follow-up height according to the actual bevel angle to realize accurate control of the bevel. Specifically, the actual follow-up height at each bevel angle is calculated through the establishment of the fitting curve, and is set in the system table for use by the numerical control system (CNC). During the cutting process, the CNC system automatically adjusts the follow-up height of the laser cutting head according to the current bevel angle and the data in the table, thereby realizing accurate control of the bevel.

[0054] The above embodiments can be realized wholly or partially by software, hardware, firmware or any combination thereof. When realized by software, the above embodiments can be realized wholly or partially 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 processes or functions described in the embodiments of the present application are wholly or partially generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network or other programmable devices. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another, for example, the computer instructions can be transmitted from one website, computer, server or data center to another website, computer, server or data center through wired (such as infrared, wireless, microwave, etc.) mode. The computer-readable storage medium can be any available medium that can be accessed by a computer or a data storage device such as a server, data center, etc. containing one or more available medium collections. The available medium can be a magnetic medium (such as a floppy disk, a hard disk, a magnetic tape), an optical medium (such as a DVD), or a semiconductor medium. The semiconductor medium can be a solid state disk.

[0055] It should be understood that the term "and / or" in this document is merely used to describe associated relationship, and it can mean three relationships, for example, A and / or B can mean that A exists alone, A and B exist together, and B exists alone, where A and B can be singular or plural. In addition, the character " / " in this document generally means that the associated objects before and after the " / " are in an "or" relationship, but can also mean an "and / or" relationship, which can be understood according to the context before and after.

[0056] In this application, "at least one" means one or more, and "multiple" means two or more. "At least one of the following" or the like means any combination of the items, including any combination of single or multiple items. For example, at least one of a, b, or c can mean a, b, c, a-b, a-c, b-c, or a-b-c, where a, b, and c can be single or multiple.

[0057] It should be understood that in various embodiments of the present application, the size of the sequence number of the above-mentioned processes does not mean the order of execution, and the execution order of the processes should be determined according to its function and inherent 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 can realize that the units and algorithm steps of the examples described in combination with the embodiments disclosed herein can be realized by electronic hardware or a combination of computer software and electronic hardware. Whether the functions are realized in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of the present application.

[0059] Those skilled in the art can clearly understand that, for the convenience and brevity of the description, the specific working process of the above-mentioned system, device and unit can be referred to the corresponding process in the foregoing method embodiments, which will not be repeated here.

[0060] In several embodiments provided in the present application, it should be understood that the disclosed system can be implemented in other ways. For example, the above-described device embodiments are only schematic, for example, the division of the units is only a logical function division, and actual implementation can have another division manner, for example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the coupling or direct coupling or communication connection between the shown or discussed objects can be indirect coupling or communication connection through some interface, device or unit, and can be electrical, mechanical or other forms.

[0061] The units described as separate components may or may not be physically separate, and the components displayed as units may or may not be physical units, that is, may be located in one place, or may be distributed on multiple network units. Part or all of the units can be selected according to actual needs to achieve the purpose of the embodiment scheme.

[0062] In addition, the functional units in each embodiment of the present application can be integrated in one processing unit, or each unit can be physically present separately, or two or more units can be integrated in one unit.

[0063] The functions, if realized in the form of software functional units and sold or used as independent products, can be stored in a computer readable storage medium. Based on such understanding, the technical solutions of the present application or the part of the present application that essentially contributes to the prior art or the part of the technical solutions can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes a plurality of instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: a U disk, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, and various program code storage media.

[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 can easily think of changes or replacements within the technical scope disclosed in the present application, which should be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to 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: Comprise: S1: by laser head scanning pipe, ensure calibration and calibration process always located on the pipe surface; S2: B-axis zero and swing length calibration, to ensure that the pipe cutting machine mechanical system and control system in the initial state, for the bevel processing to provide accurate reference; The B-axis zero-point calibration specifically comprises: adjusting the angle of the cutting head to 45°, moving the cutting head downward to touch the surface of the pipe, obtaining a Z-axis height Z1, adjusting the angle of the cutting head to -45°, moving the cutting head downward to touch the pipe, obtaining a Z-axis height Z2, obtaining the difference ΔZ of the Z-axis height of the cutting head at 45° and -45°, when the ΔZ is out of the range of -0.06~0.06, adjusting the angle of the cutting head, when the angle deviation is too large, correcting the deviation angle by 0.1 each time, when the angle deviation is small, correcting the deviation angle by 0.01 each time, until the B-axis is vertical when the ΔZ is in the range of -0.06~0.06, using a bevel single-point test program to obtain an oscilloscope pattern, when the pattern is symmetrical at both ends, the calibration of the B-axis zero-point is completed; after the calibration of the B-axis zero-point is completed, the pendulum length calibration specifically comprises: obtaining a Z-axis coordinate value after the cutting head vertically descends to touch the pipe, obtaining a second Z-axis coordinate value after the angle of the cutting head is adjusted to 45° and the cutting head descends to touch the pipe, calculating the pendulum length according to a preset pendulum length calculation formula through the angle and the difference of the two Z-axis coordinate values , wherein the preset pendulum length calculation formula is: , is the pendulum length, is the diameter of the pipe, is the angle of the cutting head, is the difference of the two Z-axis coordinate values; S3: according to the bevel calibration data and pipe parameters, the calculation of laser head irradiation angle and power, adjust the laser head follow height and feedback height, ensure that the laser head in the bevel processing process to maintain the best working condition; Calculation of laser head irradiation angle and power, adjust the laser head follow height and feedback height, including: Calibration of sensors in the vertical direction, in the case of 0°, find the pipe location, raise the cutting head to 2mm position; Rotating bevel angle to 5°; Record the actual feedback height of the current position, move 1mm along the cutting head direction, record the position of the follow height and the actual feedback height, repeat to the follow height reaches 15mm; Rotating bevel angle to 10°, 15°, 20°, 25°, 30°, 35°, 40°, 45°, -5°, -10°, -15°, -20°, -25°, -30°, -35°, -40°, -45°, after each rotation, the position of the follow height and the actual feedback height are recorded; A fitting curve is obtained according to the relationship between the following height and the actual feedback height: wherein, is the actual following height, is the reference height at 0 degree, is the current bevel angle, is 0 degree, is 45 degree, is the measured height at 45 degree; According to the obtained fitting curve, the actual follow height is calculated, and the actual follow height is set as a table, and the numerical control system calculates the current follow height according to the actual bevel angle, so as to realize accurate control of the bevel.

2. The laser head bevel following control method of a pipe cutting machine according to claim 1, characterized in that, The logic of obtaining bevel calibration data includes: Select a fixed length as gap G between 2-16mm, select 15 consecutive points according to gap G, adjust the cutting head to 0°, move down to touch the pipe to measure the Z axis coordinate to get #206, close the cutting head follow, adjust the cutting head to 45°, calculate the Z axis distance between rtcp point and actual cutting point; Read the gap value after swinging through 45°, read the current gap feedback value for 3 times through filtering 0.15s, and take the average value and store it in parameter BEVEL_GAP, through program loop, the gap feedback value corresponding to different gap G is calibrated, and is stored in parameter BEVEL_GAP in turn to complete the calibration.

3. The laser head bevel following control method of a pipe cutting machine according to claim 2, characterized in that, The calculation logic of the Z axis distance between rtcp point and actual cutting point is: #1 = #201*sin45°, #2 = #206-#201*(1-cos45°), wherein, #1 is the horizontal distance, that is, the horizontal displacement between the point of touching the pipe when the cutting head is 0° and the touch 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 swing length and the set gap G, #206 is the Z axis coordinate of the follow height when the cutting head is 0°.

Images