An in-line pipe welder

Abstract

The application discloses a pipeline internal welding machine, which comprises a machine head, a machine body and a first connecting mechanism. The machine head is provided with a tensioning mechanism and a welding mechanism. The machine body is provided with a walking system for walking in a pipeline. The machine head and the machine body are connected through the first connecting mechanism. The first connecting mechanism has controllable activity freedom to enable the machine head and the machine body to relatively deflect. In the pipeline internal welding machine, the machine head can deflect relative to the machine body, so that the whole pipeline internal welding machine changes in the form of bending, and then the pipeline internal welding machine can smoothly pass through a curved pipe section of the pipeline, can adapt to curved pipelines with different bending radii, effectively improves the bending passing capacity and has a wide application range.

Description

Technical Field

[0001] This invention relates to the field of welding equipment technology, and in particular to a pipe internal welding machine. Background Technology

[0002] Pipeline internal welding machines are widely used in pipeline construction in petrochemical, power, coal, and water transportation industries. They are mainly used to connect two pipelines and perform internal root welding. Pipelines laid in various fields typically need to adapt to the terrain, thus often exhibiting slopes and bends, especially in mountainous areas where slopes are steep and bend radii are small. Slopes can reach over 25°, and in some areas even exceed 45°, with bend radii as small as 6D (D refers to the pipe's outer diameter). Existing pipeline internal welding machines suffer from low terrain adaptability, poor passability, limited climbing ability, and poor bending ability. These machines are limited in length and can only pass through bends with large radii. When encountering bends with smaller radii, the welding machine may get stuck, unable to pass through normally and thus unable to connect and weld pipelines in curved sections, resulting in poor applicability. Summary of the Invention

[0003] The technical problem to be solved and the technical task proposed by this invention is to improve the existing technology and provide a pipe internal welding machine to solve the problem that the traditional pipe internal welding machine has poor bending ability and is difficult to perform pipe docking and welding connection in curved pipe sections.

[0004] To solve the above technical problems, the technical solution of the present invention is as follows:

[0005] A pipe welding machine includes a head, a body, and a first connecting mechanism;

[0006] The machine head is equipped with a tensioning mechanism and a welding mechanism;

[0007] The machine body is equipped with a walking system for moving inside the pipe;

[0008] The head and body are connected by a first connecting mechanism, which has controllable degrees of freedom to allow relative deflection between the head and body.

[0009] The pipeline internal welding machine is connected between the machine head and the machine body through the first connecting mechanism which can be deflected, so that the machine head can be deflected relative to the machine body, and the overall bending mode of the pipeline internal welding machine is changed when the pipeline internal welding machine passes through the curved pipe section of the pipeline, the deflection angle of the machine head relative to the machine body is adjustable, so that the curved pipe section with different bending radii can be flexibly adapted, the pipeline internal welding machine can smoothly pass through the curved pipe section, the condition that the pipeline internal welding machine is stuck in the curved pipe section is avoided, the bending passing capacity of the pipeline internal welding machine is effectively improved, and the pipeline internal welding machine can better adapt to the requirements of different terrains.

[0010] Further, the first connecting mechanism includes a static end and a dynamic end, the static end is connected with the machine body, the dynamic end is connected with the machine head, and a plurality of movable components are arranged in parallel between the static end and the dynamic end to enable the static end and the dynamic end to be relatively movable. The movable end with a parallel structure is adopted as the first connecting mechanism, multi-degree-of-freedom movement adjustment can be realized, the bending passing requirements of the pipeline internal welding machine through various curved pipe sections are met, the first connecting mechanism is a positive active adjustment structure, the relative deflection between the static end and the dynamic end is actively adjustable by controlling the changes of the movable components, and the static end and the dynamic end can be stably kept in a relatively deflected state, so that the bending radius and bending direction of the curved pipe section can be actively and accurately adjusted, and the pipeline internal welding machine can better pass along the curved pipe section.

[0011] Further, the movable component is a linear telescopic component, one end of the linear telescopic component is movably connected with the static end, and the other end is movably connected with the dynamic end. The structure is simple and compact, the relative deflection state between the static end and the dynamic end can be controlled by controlling the extension and retraction amounts of the linear telescopic components, the control is easy and the control precision is high.

[0012] Further, the first connecting mechanism is a parallel kinematic mechanism or a serial kinematic mechanism, the first connecting mechanism has two degrees of freedom to six degrees of freedom, has high flexibility, can realize deflection or even translation of the machine head relative to the machine body, flexibly and accurately adjusts the posture of the machine head relative to the machine body, and further improves the passing performance of the pipeline internal welding machine.

[0013] Further, the sensor arranged on the machine head for detecting the pipeline is further included, the control system receives and analyzes the data collected by the sensor to obtain control parameters, and the first connecting mechanism acts according to the control parameters to adjust the pose of the machine head. The sensor is used to detect the condition of the pipeline to determine the pose state of the machine head relative to the pipeline, so that the pose of the machine head is adjusted by the first connecting mechanism to adjust the machine head to an accurate posture for bending passing or welding operation, the degree of automation is improved, the pipeline internal welding machine can automatically adjust the posture according to the specific condition of the pipeline to perform bending passing, and the tensioning mechanism and the welding mechanism on the machine head can accurately align the weld area of the pipeline port, and the welding quality is improved.

[0014] Further, the sensors are arranged at intervals along the circumference of the head, and the central axis of the circumference on which the sensors are arranged coincides with the central axis of the tensioning mechanism. The pipe is detected by the sensors at multiple positions in the circumferential direction, and the data collected by the sensors is analyzed and processed comprehensively to more accurately obtain the pose state of the tensioning mechanism and the welding mechanism relative to the pipe, and the pose of the head is adjusted more accurately to enable the tensioning mechanism and the welding mechanism to accurately match the pipe, thereby improving the welding precision and quality.

[0015] Further, the sensor is a stripe laser displacement sensor to detect and collect pipe profile data. The stripe laser displacement sensor emits a linear laser stripe to irradiate on the pipe, specifically on the inner wall of the pipe and on the bevel of the pipe end, thereby forming a laser profile line on the pipe. The laser profile line image collected by the sensor is the pipe profile data. Different laser profile line images are formed when the head is at different positions and poses relative to the pipe. The pose of the head relative to the pipe can be determined by analyzing and processing the laser profile line image, and the head can be adjusted to the most accurate pose by controlling the first connecting mechanism.

[0016] Further, the control system comprises a coaxial unit for analyzing and processing the data collected by the sensors to obtain control parameters for coaxial, and the first connecting mechanism acts according to the control parameters for coaxial to make the central axis of the welding mechanism on the head coincide with the central axis of the pipe at the position of the welding mechanism. The pose of the head is automatically controlled by the first connecting mechanism according to the data collected by the sensors, and the head is kept in a state where the central axis of the welding mechanism coincides with the central axis of the pipe to achieve coaxial bending. When passing through a curved pipe section, the central axis of the pipe is deflected due to bending, and the head needs to be deflected synchronously to keep the central axis of the welding mechanism coinciding with the central axis of the pipe. The first connecting mechanism acts in real time according to the data collected by the sensors to deflect the head to maintain the state where the central axis of the welding mechanism coincides with the central axis of the pipe, thereby enabling the pipe internal welding machine to automatically adjust the deflection pose of the head relative to the machine body when passing through a curved pipe section, making the overall shape of the pipe internal welding machine curved, and thereby ensuring that the pipe internal welding machine can smoothly pass through a curved pipe section and improving the bending capability.

[0017] Further, the control system comprises a docking unit which analyzes the data collected by the sensor to obtain a control parameter for docking, and the first connecting mechanism acts according to the control parameter for docking to make the welding mechanism face the center of the weld joint between the two pipes to be docked. The pose of the head is adjusted by the first connecting mechanism according to the data collected by the sensor to realize automatic docking, and the action accuracy of the first connecting mechanism is high, which can improve the docking accuracy and efficiency.

[0018] Further, the docking unit comprises:

[0019] a scene judgment module which analyzes the data collected by the sensor to judge whether it is in a docking scene of the pipe end detected by the sensor;

[0020] a measurement module which analyzes the data collected by the sensor to obtain the distance from the sensor to the plane where the pipe end is located when it is in the docking scene;

[0021] a parking module which sends an instruction to control the walking system to park the body when the distance from the sensor to the plane where the pipe end is located reaches a walking stop condition;

[0022] a docking fine adjustment module which analyzes the data collected by the sensor in the parked state of the body to obtain a control parameter for fine adjustment, and the first connecting mechanism acts according to the control parameter for fine adjustment to make the welding mechanism face the center of the weld joint between the two pipes to be docked.

[0023] When two pipes to be docked are welded and connected, if the welding quality is to be guaranteed, the welding gun of the welding unit of the welding mechanism needs to accurately face the center of the weld joint between the two pipes. The action accuracy of the walking system on the body is low, and it is difficult to make the welding mechanism accurately align the center of the weld joint only by controlling the stop position of the walking system. Therefore, when the pipe end is detected by the sensor, the walking system is first controlled to stop the pipe inner welding machine as a whole at a position near the weld joint of the welding mechanism, specifically by detecting the distance from the sensor to the plane where the pipe end is located to control the parking position of the walking system. Then, the pose of the head is accurately adjusted by the first connecting mechanism in the parked state of the body of the pipe inner welding machine to make the welding mechanism accurately face the center of the weld joint, which has high automation degree, does not need human intervention, has high docking accuracy and efficiency, and can effectively improve the quality of welding connection.

[0024] Further, the walking system comprises a walking mechanism, the walking mechanism comprises a plurality of walking wheel assemblies arranged along the circumference of the body and connected to the tensioning mechanism arranged on the body. The structure is simple and easy to implement. The walking mechanism is mainly used to drive the body to walk along the inner wall of the pipeline. The walking wheel assemblies are pressed on the inner wall of the pipeline by the tensioning mechanism, so as to ensure that the walking wheel assemblies can stably drive the whole pipeline welding machine to walk along the pipeline when the walking wheel assemblies are running, improve the climbing ability of the pipeline welding machine, avoid the situation of slipping and sliding, and be applicable to the inclined pipe section with large slope.

[0025] Further, the walking wheel assembly is arranged on both sides of the diameter direction of the body, and the tensioning mechanism is a tensioning hydraulic cylinder connected between the two walking wheel assemblies. The structure is simple and compact. The distance between the two walking wheel assemblies is adjusted by the tensioning hydraulic cylinder, so that the walking wheel assemblies are pressed on the inner wall of the pipeline. The tensioning hydraulic cylinder uses hydraulic pressure to provide tensioning force, which can improve the tensioning force without increasing the volume, and ensure the stability of the pipeline welding machine walking along the pipeline.

[0026] Further, each walking wheel assembly is provided with a walking motor, so that each walking wheel assembly can be independently controlled, and the rotating speed of each walking wheel assembly can be flexibly adjusted according to needs. In particular, when passing through a bend, the walking wheel assemblies are controlled by electronic differential, that is, the walking speed of the walking wheel assembly on the inner side of the curved pipe section is lower than that of the walking wheel assembly on the outer side of the curved pipe section, so as to improve the reliability of passing through the bend, avoid the situation that the pipeline welding machine is stuck in the curved pipe section, and avoid damage to the walking motor due to excessive resistance.

[0027] Further, the walking system comprises a brake mechanism, the brake mechanism comprises a brake cylinder, a brake pad and a retaining elastic member, the brake pad is driven by the brake cylinder to switch between the brake position and the release position, and the brake pad is further connected with the retaining elastic member for driving the brake pad to be retained in the brake position. The brake reliability is improved. Even if the brake cylinder is damaged and does not work, the brake pad can still be retained in the state of abutting against the brake position in the inner wall of the pipeline under the action of the retaining elastic member, so as to avoid the situation of sliding and make the pipeline welding machine stop stably in the pipeline with large slope, improve the reliability and safety.

[0028] Further, the walking system comprises a flexible wheel assembly, the flexible wheel assembly comprises a wheel, a wheel seat and an elastic assembly, the wheel is arranged on the wheel seat, the wheel seat is hinged on the body, the rotation plane of the wheel seat is along the radial direction of the body, and the elastic assembly is connected between the wheel seat and the body. The wheel in the flexible wheel assembly can be buffered and stretched in the radial direction of the body relative to the body. When the pipe internal welding machine is subjected to an external force, for example, the tensioning mechanism works against the inner wall of the pipe or the machine head collides with the inner wall of the pipe, the wheel can be deflected relative to the body with the wheel seat, and then the elastic assembly is elastically deformed. The elastic assembly can buffer and absorb the impact force, so that the pipe internal welding machine is not damaged by the impact, and the pipe internal welding machine is effectively protected.

[0029] Further, the flexible wheel assembly further comprises an angle adjusting motor arranged on the wheel seat and connected with the wheel, and the angle adjusting motor adjusts the traveling direction of the wheel. During the process that the pipe internal welding machine travels along the inner wall of the pipe, it is difficult to ensure that the posture of the pipe internal welding machine is constant. The pipe internal welding machine will inevitably rotate relative to the pipe. The angle adjusting motor drives the wheel to turn, so that the pipe internal welding machine rotates relative to the pipe, and then the pipe internal welding machine returns to the required posture.

[0030] Further, the battery unit is further included, and the battery unit supplies power for the tensioning mechanism, the welding mechanism, the walking system and the first connecting mechanism. The integrated degree is high, the battery unit is used for centralized power supply, and the application of the pipe internal welding machine is more flexible.

[0031] Further, the body is divided into a plurality of segments along the pipe axis direction, and adjacent segments are connected through a second connecting mechanism. The second connecting mechanism is a deflectable connecting mechanism. The body with a certain length is divided into a plurality of segments, and adjacent segments can be relatively deflected through the second connecting mechanism, so that the body itself can be curved and deformed, so that the pipe internal welding machine can pass through a curved pipe segment with a smaller bending radius, and the bending passing ability of the pipe internal welding machine is further improved.

[0032] Further, the second connecting mechanism comprises a first end, a second end, a universal joint and flexible connecting pieces, the universal joint and the flexible connecting pieces are connected between the first end and the second end, the flexible connecting pieces are distributed in the circumferential direction of the universal joint, the first end is connected with the front section, and the second end is connected with the rear section. The structure is simple and easy to implement, the second connecting mechanism is a passive deflection connecting structure, and active adjustment is not needed. When the pipe internal welding machine passes through the curved pipe section, each section of the machine body is in contact with the inner wall of the pipe, and under the abutting force of the inner wall of the pipe on each section, the adjacent sections are relatively deflected through the second connecting mechanism to match the bending radius of the curved pipe section, so that the machine body is passively changed into a bending shape matching the bending radius of the curved pipe section, and thus the pipe internal welding machine can smoothly pass through the curved pipe section.

[0033] In order to improve the flexibility of the internal welding machine in the pipe, the prior art sets the internal welding machine into multiple sections and connects them through universal joints to improve the bending passing capacity. However, in the process, the internal welding machine is affected by the inner circumferential surface of the pipe and rotates spirally when running in the pipe, changes the initial welding position of the welding head on the welding assembly of the internal welding machine, and thus affects the welding lap joint quality and construction efficiency. Generally, manual non-quantitative adjustment is needed for the posture, and the controllable precision and efficiency of the running posture are low.

[0034] The present application provides a posture adjusting system of an internal welding machine,

[0035] which comprises a posture adjusting device, a sensor and an electrical control module, the posture adjusting device is arranged between a first section and a second section of the internal welding machine,

[0036] the posture adjusting device comprises a moving platform, a fixed platform and a linear driving mechanism, the moving platform is connected with the first section, the fixed platform is connected with the second section, and the two ends of the linear driving mechanism are movably connected with the moving platform and the fixed platform respectively;

[0037] the sensor is used for collecting pipe profile data on the circumferential side of the moving platform of the first section;

[0038] the linear driving mechanism is connected with the electrical control module, the electrical control module is used for calculating a target posture of the first section according to the pipe profile data, and adjusting the linear driving mechanism so that the axis of the moving platform on the first section is in the target posture.

[0039] Further, the posture adjusting device further comprises a moving end mounting seat and a fixed end mounting seat,

[0040] the moving end mounting seat is fixed on the moving platform through bolts, and one end of the linear driving mechanism is movably connected on the moving end mounting seat through a universal joint,

[0041] The fixed end mounting base is fixed to the fixed platform by bolts, and the other end of the linear driving mechanism is detachably connected to the fixed end mounting base through a universal joint.

[0042] Further, the posture adjusting device is a six-degree-of-freedom motion platform including six linear driving mechanisms.

[0043] Further, the sensors are a plurality of sensors, and all the sensors are uniformly distributed along the circumference of the first section.

[0044] Further, the sensors are stripe laser sensors, and the sensors are used to obtain a laser profile line projected on the inner circumferential surface of the pipe to obtain pipe profile data of the first section.

[0045] Further, the electrical control module includes:

[0046] a motion controller configured to calculate a target posture of the first section according to the pipe profile data, and perform a motion inverse algorithm calculation on the target posture to generate a length change signal of the linear driving mechanism;

[0047] a servo driver configured to generate a corresponding pulse signal according to the length change signal issued by the motion controller;

[0048] a servo motor configured to rotate according to the pulse signal issued by the servo driver to drive the corresponding linear driving mechanism to perform a telescopic motion until the first section is in the target posture.

[0049] A posture adjusting method of an internal welding machine based on the system, for adjusting the positional relationship between the first section and the second section of the internal welding machine, including:

[0050] collecting pipe profile data of the first section;

[0051] calculating a target posture of the first section according to the pipe profile data, and generating an adjusting signal based on the target posture;

[0052] driving the linear driving mechanism based on the adjusting signal to make the axis of the first section in the target posture.

[0053] Further, the step of calculating a target posture of the first section according to the pipe profile data, and generating an adjusting signal based on the target posture specifically includes:

[0054] transforming the profile data scanned by each sensor into corrected profile data in the first section coordinate system based on a known sensor installation correction coefficient;

[0055] Based on the corrected contour data, the pipe pose information of the current pipe in the first sub-section coordinate system is calculated;

[0056] Based on the pipe pose information, the target pose of the first sub-section is calculated, and an adjustment signal is generated based on the target pose.

[0057] The application also provides a storage medium having a computer program stored thereon, wherein the computer program is executed to implement the steps of the pose adjustment method of the internal welding machine.

[0058] The application also provides an internal welding machine, comprising a first sub-section, a second sub-section, and a pose adjustment system.

[0059] The pose adjustment system comprises a pose adjustment device, an electrical control module, and a sensor.

[0060] The pose adjustment device is arranged between the first sub-section and the second sub-section, and comprises a moving platform, a fixed platform, a linear driving mechanism, and a universal joint. The moving platform is in an integral structure with the rack of the first sub-section, the fixed platform is in an integral structure with the rack of the second sub-section, and the two ends of the linear driving mechanism are connected with the moving platform and the fixed platform through the universal joint, respectively.

[0061] The sensor is used to collect the pipe contour data on the periphery of the moving platform of the first sub-section.

[0062] The electrical control module is used to calculate the target pose of the first sub-section according to the pipe contour data, and to generate a length change signal of the linear driving mechanism by solving the target pose. The electrical control module is also used to control the linear driving mechanism to perform extension and contraction movement by using the length change signal, so that the first sub-section is in the target pose.

[0063] The application provides a posture adjusting system of an internal welding machine, the internal welding machine comprising a first section, a second section and a posture adjusting device, the posture adjusting device being arranged between the first section and the second section; the posture adjusting device comprising a movable platform, a fixed platform, a linear driving mechanism and a universal joint, the movable platform and a rack of the first section being in an integral structure, the fixed platform and a rack of the second section being in an integral structure, two ends of the linear driving mechanism being connected with the movable platform and the fixed platform through the universal joint respectively; the sensor is used for collecting pipeline profile data of a position where the movable platform of the internal welding machine is located; the electrical control module is used for calculating a target posture of the first section according to the pipeline profile data, and performing calculation of a motion inverse solution algorithm on the target posture to generate a length change signal of the linear driving mechanism; the electrical control module is also used for controlling the linear driving mechanism to perform extension and contraction movement by using the length change signal, so that the first section is in the target posture.

[0064] The posture adjusting device provided by the application is arranged between the first section and the second section of the internal welding machine, and comprises a movable platform, a fixed platform, a linear driving mechanism and a universal joint. Since the movable platform and the rack of the first section are in an integral structure, and the fixed platform and the rack of the second section are in an integral structure, when the linear driving mechanism of the posture adjusting device performs extension and contraction movement, the posture of the first section can be changed. In the application, the electrical control module calculates a target posture of the first section according to the pipeline profile data in the working process, and performs calculation of a motion inverse solution algorithm on the target posture to generate a length change signal of the linear driving mechanism, and then controls the linear driving mechanism to perform extension and contraction movement by using the length change signal, so that the first section is in the target posture. The application can realize automatic adjustment of the posture of the internal welding machine according to the pipeline profile data, and improve the welding quality. The application also provides an internal welding machine posture adjusting method, a storage medium and an internal welding machine, which have the above beneficial effects.

[0065] When the internal welding machine works on a bent pipe, since the shape of the pipe changes, the internal welding machine is prone to have a large deviation between the welding position and the weld position of the pipe bevel, and the alignment accuracy is low, and often needs to be manually adjusted by the staff. The internal welding machine has a heavy self weight, and the manual adjustment by the staff often needs a long adjustment time and is inconvenient to operate.

[0066] The application provides an internal welding machine alignment method, comprising:

[0067] detecting pipeline profile data of a welding unit of the internal welding machine, and judging whether a pipe end face is detected based on the pipeline profile data;

[0068] When the sensor for detecting the pipe profile data meets a preset distance with the plane where the pipe end surface is located, the control of the inner welding machine driving mechanism makes the inner welding machine stop driving along the pipe axis direction;

[0069] The pose information is obtained by calculating the positional relationship between the sensor and the pipe end surface, and the multi-degree-of-freedom adjusting mechanism between the inner welding machine cone head mechanism and the body mechanism is adjusted through the pose information, so that the welding unit on the inner welding machine cone head mechanism is directly opposite to the to-be-welded groove and the inner welding machine is relatively fixed with the pipe.

[0070] Further, the step of detecting the pipe profile data around the welding unit of the inner welding machine comprises:

[0071] The pipe profile data is obtained by the sensor on the inner welding machine cone head mechanism,

[0072] The pipe profile data is obtained by the sensor on the inner welding machine cone head mechanism,

[0073] According to the comparison result, it is judged whether the pipe end surface is detected.

[0074] Further, the sensor is a stripe laser displacement sensor, and the sensor is used to obtain the pipe profile data containing the pipe inner circumferential surface or the pipe end surface data through linear laser scanning.

[0075] Further, the step of controlling the inner welding machine driving mechanism to stop driving along the pipe axis direction when the sensor for detecting the pipe profile data meets a preset distance with the plane where the pipe end surface is located comprises:

[0076] When the pipe end surface is detected and the matching result is greater than 1,

[0077] It is judged whether the positional relationship between the sensor and the plane where the pipe end surface is located meets a preset distance relationship, and when the preset distance relationship is met, the control of the inner welding machine driving mechanism makes the inner welding machine stop driving along the pipe axis direction, so that the welding unit stops in the groove area.

[0078] Further, the step of controlling the inner welding machine driving mechanism to stop driving along the pipe axis direction before the step further comprises:

[0079] The pipe profile data is processed to obtain the coarse error translation and coarse error rotation values of the pipe profile compared with the cone head mechanism;

[0080] The multi-degree-of-freedom platform is adjusted so that the central axis of the welding unit is coaxial with the central axis of the pipe around it.

[0081] Further, the step of calculating the positional relationship between the sensor and the pipe end surface to obtain the pose information comprises:

[0082] Collecting profile data of the pipeline to obtain a profile image, and performing corner point detection to obtain coarse error coordinate values of each vertex of the profile image;

[0083] Taking the coarse error coordinate values of each vertex of the profile image as initial values, fitting the profile data according to a bevel profile shape to obtain accurate coordinates of each vertex of the profile;

[0084] Converting the accurate coordinates of each vertex of the profile into bevel feature space coordinates in a coordinate system of the cone head mechanism;

[0085] Calculating the position and pose of the current bevel in the coordinate system of the cone head mechanism through the bevel feature point space coordinates;

[0086] Obtaining pose information, the pose information including an angle offset and a displacement between the bevel and the cone head mechanism.

[0087] Further, the step of fitting the profile data according to a bevel profile shape to obtain accurate coordinates of each vertex of the profile includes:

[0088] Constructing a bevel profile mathematical model corresponding to the profile data with the coordinates of the corner points as initial values;

[0089] Solving the profile mathematical model by using an optimization objective function of the least square method to obtain accurate coordinates of each vertex of the profile.

[0090] Further, the step of adjusting a multi-degree-of-freedom adjusting mechanism between the cone head mechanism and the body mechanism of the internal welding machine according to the pose information, so that a welding unit on the cone head mechanism of the internal welding machine is directly opposite the to-be-welded bevel and the internal welding machine is relatively fixed to the pipeline includes:

[0091] Adjusting the multi-degree-of-freedom adjusting mechanism between the cone head mechanism and the body mechanism of the internal welding machine according to the pose information, and making the welding torch in the welding unit on the cone head mechanism directly opposite the bevel by adjusting the extension amount of one or more electric cylinders in the multi-degree-of-freedom adjusting mechanism;

[0092] After the pose of the cone head mechanism is adjusted, the tensioning mechanism is extended to relatively fix the internal welding machine to the pipeline.

[0093] The application also provides an internal welding machine alignment device, which includes tensioning units distributed circumferentially along a head of an internal welding machine, and further includes:

[0094] A sensor for detecting profile data of a pipeline on a circumferential side of a welding unit of the internal welding machine, and determining whether a pipe end surface is detected based on the profile data;

[0095] A control system for controlling a driving mechanism of the internal welding machine to stop driving the internal welding machine along an axial direction of the pipeline when the sensor for detecting the profile data and a plane in which the pipe end surface is located satisfy a preset distance;

[0096] The control system is also used to calculate pose information of a position relationship between the sensor and the pipe end face, and adjust a multi-degree-of-freedom adjusting mechanism between the inner welding machine cone head mechanism and the machine body through the pose information, so that the welding unit on the inner welding machine cone head mechanism is directly opposite the to-be-welded groove and the inner welding machine is relatively fixed with the pipe.

[0097] The application also provides an inner welding machine, which comprises a cone head mechanism, a machine body mechanism, a sensor, a multi-degree-of-freedom adjusting mechanism, a memory and a processor, the sensor is arranged on the cone head mechanism, the multi-degree-of-freedom adjusting mechanism is arranged between the cone head mechanism and the machine body mechanism, the memory stores a computer program, and the processor realizes the steps of the above-mentioned inner welding machine alignment method when calling the computer program in the memory.

[0098] The application also provides a storage medium, which stores a computer program, and the computer program realizes the steps of the above-mentioned inner welding machine alignment method when being executed.

[0099] The application provides an inner welding machine alignment method, which comprises a sensor arranged on a cone head mechanism and a multi-degree-of-freedom adjusting mechanism arranged between the cone head mechanism and a machine body mechanism, and the inner welding machine alignment method comprises the following steps: collecting pipe profile data by using the sensor, determining a target stop position by using the pipe profile data, and controlling the inner welding machine to move to the target stop position; wherein, when the inner welding machine moves to the target stop position, a welding unit in the cone head mechanism moves to a groove area; determining a groove feature point according to the pipe profile data, determining groove pose information of a pipe groove in a cone head mechanism coordinate system according to the spatial coordinates of the groove feature point in the cone head mechanism coordinate system; adjusting the pose of the cone head mechanism according to the groove pose information by using the multi-degree-of-freedom adjusting mechanism, so that the welding torch of the welding unit is directly opposite the weld center of the pipe groove; and performing pipe alignment operation at a position corresponding to the pipe groove.

[0100] The application adjusts the pose of the cone head mechanism according to the groove pose information by using the multi-degree-of-freedom adjusting mechanism, so that the welding torch of the welding unit is directly opposite the weld center of the pipe groove. Through the above-mentioned mode, the welding torch of the welding unit of the inner welding machine can be automatically adjusted to a position directly opposite the weld center of the pipe groove in the alignment scene, so that the inner welding machine realizes high-precision automatic alignment, and the welding quality is improved. The application also provides an inner welding machine alignment device, a storage medium and an inner welding machine, which have the above-mentioned beneficial effects, and details are not repeated here.

[0101] Compared with the prior art, the application has the following advantages:

[0102] The head of the pipe internal welding machine can be deflected relative to the machine body, so that the overall pipe internal welding machine changes in bending mode, and the pipe internal welding machine can smoothly pass through the curved pipe section of the pipe, can adapt to the curved pipe with different bending radii, effectively improves the bending passing capacity, and flexibly adapts to the requirements of different terrains;

[0103] The first connecting mechanism is a positive active adjustment structure, which can actively adjust the deflection posture of the head relative to the machine body, and can more smoothly pass through the curved pipe section without obstruction;

[0104] The degree of automation is high, without human intervention, the posture of the machine body can be automatically adjusted according to the pipe condition to realize automatic bending passing, and automatic alignment can be realized, the welding mechanism is accurately aligned with the center of the weld, the alignment efficiency is high, the precision is high, and the welding quality is improved. BRIEF DESCRIPTION OF DRAWINGS

[0105] Figure 1 It is a whole schematic view of the pipe internal welding machine of the application;

[0106] Figure 2 It is a top view structural schematic view; Figure 1

[0107] Figure 3 It is a structure schematic view of the tensioning mechanism and the welding mechanism arranged on the head;

[0108] Figure 4 It is a structure view of the welding unit;

[0109] Figure 5 It is a structure schematic view of the tensioning mechanism and the welding mechanism on the head and the two pipes to be connected;

[0110] Figure 6 It is a structure schematic view of the first connecting mechanism;

[0111] Figure 7 It is another structure schematic view of the first connecting mechanism;

[0112] Figure 8 It is a structure schematic view of the movable member;

[0113] Figure 9 It is a structure schematic view of an end view of the head;

[0114] Figure 10 It is a structure schematic view of the laser stripe emitted by the sensor irradiating on the pipe to form a laser contour line;

[0115] Figure 11 It is another structure schematic view of the laser stripe emitted by the sensor irradiating on the pipe to form a laser contour line; ​

[0116] Figure 12 A schematic diagram of another structure for the laser stripe emitted by the sensor to form a laser profile line on the pipe;

[0117] Figure 13 A schematic diagram of a structure for the traveling mechanism;

[0118] Figure 14 A schematic diagram of a structure for the brake mechanism;

[0119] Figure 15 A schematic diagram of a structure for the flexible wheel assembly;

[0120] Figure 16 A schematic diagram of a structure for the hydraulic system;

[0121] Figure 17 A schematic diagram of the overall structure of another pipe internal welding machine according to the present application;

[0122] Figure 18 A schematic diagram of the structure of an integrated intelligent pipe internal welding machine provided by the present application;

[0123] Figure 19 A schematic diagram of the structure of a posture adjustment system provided by the present application;

[0124] Figure 20 A schematic diagram of the structure of a posture adjustment device provided by the present application;

[0125] Figure 21 A flowchart of a posture adjustment method for an internal welding machine provided by the present application;

[0126] Figure 22 A schematic diagram of the structure of an internal welding machine for bending pipes provided by the present application;

[0127] Figure 23 A general design diagram of a control system provided by the present application;

[0128] Figure 24 A flowchart of a method for aligning the opening of an internal welding machine provided by the present application;

[0129] Figure 25 A schematic diagram of the structure of an internal welding machine provided by the present application;

[0130] Figure 26 A local enlarged schematic diagram of the welding unit and the bevel during the aligning process provided by the present application;

[0131] Figure 27 A schematic diagram of the bevel profile data collected by the sensor being converted into a picture through downsampling provided by the present application;

[0132] Figure 28 A schematic diagram of the result of the angle point detection of the groove profile provided by the embodiment of the present application;

[0133] Figure 29 A schematic diagram of the result of the groove profile provided by the embodiment of the present application;

[0134] In the figure:

[0135] Head 1, body 2, first connecting mechanism 3, static end 31, dynamic end 32, movable member 33, inclined slide rail 331, sliding block 332, driving mechanism 333, actuator rod 334, tensioning mechanism 11, front tensioning assembly 111, rear tensioning assembly 112, welding mechanism 12, welding unit 121, sensor 4, traveling mechanism 51, traveling wheel assembly 511, clamping mechanism 512, traveling motor 513, brake mechanism 52, brake cylinder 521, brake pad 522, retaining elastic member 523, flexible wheel assembly 53, wheel 531, wheel seat 532, elastic assembly 533, angle adjusting motor 534, rear wheel 54, battery unit 6, welding power supply 7, hydraulic system 8, front tensioning cylinder 81, rear tensioning cylinder 82, traveling cylinder 83, protection gas cylinder 9, second connecting mechanism 10, first end 101, second end 102, universal joint 103, flexible connecting member 104;

[0136] First sub-section 201, welding device 202, tensioning assembly 203, attitude adjusting device 204, second sub-section 205, movable platform 2041, linear driving mechanism 2042, fixed platform 2043, movable end mounting seat 2044, fixed end mounting seat 2045;

[0137] Conical head mechanism 301, multi-degree-of-freedom adjusting mechanism 303, welding unit 304, tensioning device 306, body mechanism 302, traveling device 308, brake device 309, flexible front wheel 3010, fixed steel pipe 3011, groove region 3012. DETAILED DESCRIPTION

[0138] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0139] The embodiment of the present application discloses a pipeline internal welding machine, which effectively improves the bending capacity and passing performance, has good controllability and high precision in attitude adjustment, and can accurately and efficiently perform pipeline butt joint and welding connection.

[0140] Embodiment one

[0141] As shown in Figure 1 and Figure 2 , a pipe welding machine mainly comprises a head 1, a body 2 and a first connecting mechanism 3;

[0142] The head 1 is provided with a tensioning mechanism 11 and a welding mechanism 12;

[0143] The body 2 is provided with a walking system for walking inside the pipe;

[0144] The head 1 and the body 2 are connected through the first connecting mechanism 3, which has controllable activity freedom to enable the head 1 and the body 2 to relatively deflect.

[0145] As shown in Figures 1 to 3 , the tensioning mechanism 11 comprises a front tensioning assembly 111 and a rear tensioning assembly 112 which are axially spaced along the pipe, and the welding mechanism 12 is arranged between the front tensioning assembly 111 and the rear tensioning assembly 112, the front tensioning assembly 111 and the rear tensioning assembly 112 each comprise a plurality of tensioning units which are distributed along the circumference, the welding mechanism 12 comprises a plurality of welding units 121 which are distributed along the circumference, the tensioning mechanism 11 and the welding mechanism 12 have the same central axis, that is, the distribution circumferences of the tensioning units and the welding units have the same central axis, and the welding unit 121 is a welding execution mechanism which is provided with components such as a wire reel, a wire feeder and a welding gun, as shown in Figure 4 , and performs welding operation on the annular gap between the bevels of the two pipe ends, so that the internal bevels of the two pipe ends are welded into one body;

[0146] The body 2 of the pipe welding machine walks along the inside of the fixed pipe through the walking system, the head 1 moves together with the body 2, and finally the head 1 is moved to the position of the welding seam between the two pipes to be connected, as shown in Figure 5The welding torch of each welding unit of the welding mechanism 12 on the machine head 1 is directly opposite the welding seam center between the two pipe end bevels to be butt-jointed (here, the welding seam refers to the annular gap between the two pipe end bevels to be butt-jointed which has not been welded and connected yet), and the front and rear tensioning assemblies 111 and 112 are located on the two sides of the welding mechanism 12 in the axial direction, so that the front and rear tensioning assemblies 111 and 112 are respectively located in the two pipes to be butt-jointed, and the front and rear tensioning assemblies 111 and 112 respectively expand to the radial outside to tightly press the inner wall of the pipes, so that the two pipes are fixed with the front and rear tensioning assemblies 111 and 112 respectively, and the welding seam between the two pipes is kept in a fixed state, and the welding mechanism 12 is kept in a state of directly opposite to the welding seam center, so that the welding operation can be stably and accurately performed, and the welding quality is improved.

[0147] In the present embodiment, as Figure 1 , Figure 2 and Figure 6As shown, the first connecting mechanism 3 is a controllable movable connecting mechanism, which can make the head 1 deflect controllably relative to the body 2 as needed, so that the whole pipe internal welding machine becomes curved, thereby being able to pass through the curved pipe section of the pipe, improving the bending passing ability of the pipe internal welding machine. Specifically, the first connecting mechanism 3 includes a static end 31 and a dynamic end 32, the static end 31 is connected with the body 2, and the dynamic end 32 is connected with the head 1. A plurality of controllable movable members 33 are arranged in parallel between the static end 31 and the dynamic end 32 to enable the static end 31 and the dynamic end 32 to move relative to each other. The first connecting mechanism 3 is a multi-degree-of-freedom parallel motion mechanism. Preferably, six movable members 33 are arranged in parallel between the static end 31 and the dynamic end 32, so that the first connecting mechanism 3 constitutes a six-degree-of-freedom parallel motion mechanism, which has six degrees of freedom. In terms of a three-dimensional orthogonal coordinate system, the first connecting mechanism 3 includes movement degrees of freedom along x, y and z axes respectively, and also includes rotation degrees of freedom around x, y and z axes respectively. Specifically, when the pipe internal welding machine is in the pipe, the head 1 and the body 2 are distributed forward and backward along the axial direction of the pipe, so that the static end 31 and the dynamic end 32 of the first connecting mechanism 3 are distributed forward and backward along the axial direction of the pipe. The axial direction of the pipe is defined as the z-axis direction, and the cross-sectional direction of the pipe is defined as the x-y plane direction. When the body 2 of the pipe internal welding machine is in the pipe, the body 2 is in a stable state relative to the pipe, while the head 1 can translate along the axial direction of the pipe, or translate along the cross-sectional direction of the pipe, or rotate around the axial direction of the pipe, or rotate around any radial direction of the cross-sectional direction of the pipe, under the action of the first connecting mechanism 3 relative to the body 2. Overall, the head 1 can move and deflect flexibly and accurately relative to the body 2 under the action of the first connecting mechanism 3, and can accurately match the needs of the curved pipe section with various bending radii, so that the whole pipe internal welding machine can be bent to the required bending degree, and then smoothly pass through the curved pipe section.

[0148] In the embodiment, the movable member 33 is a linear telescopic member, one end of which is movably connected with the static end 31, and the other end of which is movably connected with the dynamic end 32. Specifically, the two ends of the linear telescopic member are connected with the static end 31 and the dynamic end 32 through universal joints, respectively. The dynamic end 32 can be driven to move relative to the static end 31 by controlling the telescopic amount of each linear telescopic member. The first connecting mechanism 3 includes the movement of six degrees of freedom, and the dynamic end 32 can move in translation and deflection relative to the static end 31. The structure is compact, and the control is convenient and accurate. The linear telescopic member can be a pneumatic cylinder, a hydraulic cylinder, an electric cylinder, etc. In the embodiment, an electric cylinder is preferably used. Compared with pneumatic and hydraulic forms, the electric cylinder has the advantages of high transmission efficiency, high speed, high positioning accuracy, silent operation, simple structure, easy maintenance, high reliability and safety, stable operation, long service life, etc. Thus, the pose of the head 1 can be accurately adjusted, the head 1 is deflected relative to the body 2 to make the whole pipe welding machine become a curved shape to pass through the curved pipe section, the overbending ability is improved, the head 1 can also move in translation along the axis direction of the pipe, so that the tensioning mechanism 11 and the welding mechanism 12 on the head 1 can accurately match the end of the pipe, and finally the welding mechanism 12 accurately points to the center of the weld between the two pipe ends to be connected, thereby improving the welding quality.

[0149] The first connecting mechanism 3 in the embodiment specifically adopts a six-degree-of-freedom parallel motion mechanism. The first connecting mechanism 3 can also adopt a six-degree-of-freedom serial motion mechanism, for example, a jointed mechanical arm, or three linear motion mechanisms connected in series and each provided with a rotating mechanism. Compared with the six-degree-of-freedom serial motion mechanism, the six-degree-of-freedom parallel motion mechanism has large rigidity and good structural stability. Since the six-degree-of-freedom parallel motion mechanism has larger rigidity, it has higher carrying capacity under the condition that the six-degree-of-freedom parallel motion mechanism and the six-degree-of-freedom serial motion mechanism have the same weight or volume. The output error of the end of the six-degree-of-freedom serial motion mechanism is the accumulation and amplification of the errors of each joint, so the overall movement error is large and the precision is low. The six-degree-of-freedom parallel motion mechanism has no accumulation and amplification relationship, and the overall movement error of the six-degree-of-freedom parallel motion mechanism is the average of the errors of each moving component, so the error is small and the precision is high. The walking motor and transmission system of the six-degree-of-freedom serial motion mechanism are mostly placed on the moving jointed arm, which increases the inertia of the system and worsens the dynamic performance. The walking motor of the six-degree-of-freedom parallel motion mechanism is usually arranged on the static end, which reduces the movement load. The six-degree-of-freedom parallel motion mechanism adopts a symmetrical structure, and each moving component is symmetrically distributed in the circumferential direction, so it has good isotropy. The working space of the six-degree-of-freedom parallel motion mechanism is small, that is, it can be adjusted in a small space range. The working space of the six-degree-of-freedom serial motion mechanism is large. Further, in position solving, the six-degree-of-freedom serial motion mechanism has easy forward solution but complex inverse solution, while the six-degree-of-freedom parallel motion mechanism has complex forward solution but very easy inverse solution. The forward solution of the six-degree-of-freedom parallel motion mechanism refers to solving the position and attitude of the moving end when the extension amount of the moving component is known, and the inverse solution refers to solving the extension amount of the moving component when the position and attitude of the moving end are known.

[0150] The prior art also has a flexible deflection mechanism connected between the machine head and the machine body, so that the machine head can be deflected relative to the machine body to realize overbending. However, the flexible deflection mechanism used in the prior art is usually a universal joint structure or a structure composed of a universal joint and an elastic component. This kind of flexible deflection mechanism realizes passive deflection, that is, only when the pipe internal welding machine travels to the curved pipe section and the machine head touches the inner wall of the curved pipe section, the flexible deflection mechanism can be activated under the reaction force of the inner wall of the curved pipe section on the machine head, so that the machine head is deflected relative to the machine body, and then the machine head passes through the curved pipe section in a deflected state. During the entire process of passing through the curved pipe section, the machine head is always in contact with the inner wall of the curved pipe section, which can easily cause wear between the machine head and the inner wall of the pipe. The first connecting mechanism 3 of the present embodiment realizes active deflection. By controlling the first connecting mechanism, the moving end 32 is actively deflected relative to the static end 31, that is, the machine head 1 is deflected relative to the machine body 2 as the pipe bends, so that the pipe internal welding machine becomes curved to pass through the curved pipe section. Preferably, the machine head 1 can be actively maintained in a state where the central axis of the machine head 1 coincides with the central axis of the pipe at the position of the machine head 1 in the pipe (the welding units 121 of the welding mechanism 12 are circumferentially distributed on the machine head 1, and the central axis of the welding mechanism 12 coincides with the central axis of the machine head 1, so that when the central axis of the machine head 1 coincides with the central axis of the pipe at the position of the machine head 1 in the pipe, the central axis of the welding mechanism 12 also coincides with the central axis of the pipe at the position of the welding mechanism 12 in the pipe). Thus, the outer periphery of the tensioning mechanism 11 and the connecting mechanism 12 on the machine head 1 maintains a uniform spacing with the inner wall of the pipe in the entire circumferential direction. During the entire process of passing through the curved pipe section, the machine head does not come into contact with the inner wall of the curved pipe section, which can better ensure the smoothness and safety and reliability of overbending. Of course, if only to realize active and smooth overbending, as long as the machine head 1 can be deflected relative to the machine body 2 and the machine head 1 does not come into contact with the inner wall of the pipe, the central axis of the machine head 1 does not need to completely coincide with the central axis of the pipe at the position of the machine head 1 in the pipe. The central axis of the machine head 1 can be parallel to or have a small angle with the central axis of the pipe at the position of the machine head 1 in the pipe. As long as there is a spacing between the machine head 1 and the pipe in the entire circumferential direction, the spacing does not need to be uniform in the entire circumferential direction.

[0151] In the case that the pipe inner welding machine connects the head 1 to the body 2 through the first connecting mechanism 3, the pipe inner welding machine can adopt the manual control of the first connecting mechanism 3 to bend, specifically, the movable end 32 is moved relative to the static end 31 by manually controlling each movable member 33 in the first connecting mechanism 3, in other words, the first connecting mechanism 3 is manually controlled to make the head 1 translate or deflect relative to the body 2, specifically, it can be observed in the field, that is, the position and attitude of the head 1 relative to the curved pipe segment are observed, and then the first connecting mechanism 3 is manually controlled to move the head 1 relative to the body 2 until the distance between the head 1 and the inner wall of the curved pipe segment is substantially uniform in the entire circumference, that is, the head 1 deflects relative to the body 2 and reaches the state that the central axis of the head 1 coincides with the central axis of the pipe at the position of the head 1, in other words, the pipe inner welding machine actively and adaptively deforms according to the curved pipe segment, so that the pipe inner welding machine can smoothly pass through the curved pipe segment; or the deflection attitude of the head 1 relative to the body 2 is calculated according to the bending radius of the curved pipe segment, and then the first connecting mechanism 3 is manually controlled or system controlled to move the head 1 relative to the body 2 to accurately deflect, so that the pipe inner welding machine actively and adaptively deforms according to the curved pipe segment, and finally ensures that the pipe inner welding machine can smoothly pass through the curved pipe segment.

[0152] Embodiment Two

[0153] As Figure 7 and Figure 8As shown, on the basis of the first connecting mechanism 3 of the embodiment, the first connecting mechanism 3 is replaced by another structure, the first connecting mechanism 3 includes a static end 31 and a dynamic end 32, the static end 31 is connected with the machine body 2, the dynamic end 32 is connected with the machine head 1, six controllable movable members 33 are arranged in parallel between the static end 31 and the dynamic end 32 to enable the static end and the dynamic end to be relatively movable, specifically, the movable member 33 includes an actuating rod 334 and an inclined movement mechanism, the inclined movement mechanism includes an inclined slide rail 331, a sliding block 332 and a driving mechanism 333, the inclined slide rail 331 is fixedly arranged on the static end 31, the sliding guide direction of the inclined slide rail 331 is inclined to the reference plane formed by the static end 31, the sliding block 332 is slidably arranged on the inclined slide rail 331, the sliding block 332 is driven by the driving mechanism 333 to slide along the inclined slide rail 331, the driving mechanism 333 can be a motor-driven screw pair mechanism, a motor-driven gear and rack cooperation structure, a synchronous belt mechanism and the like, the actuating rod 334 is a rigid body with a length that cannot be extended or retracted, one end of the actuating rod 334 is connected with the sliding block 332 through a universal joint, the other end of the actuating rod 334 is connected with the dynamic end 32 through a universal joint, every two movable members 33 are symmetrically arranged to form a group, the six movable members 33 between the static end 31 and the dynamic end 32 are divided into three groups, the three groups are annularly formed and uniformly distributed in the circumferential direction, specifically, the inclined slide rail 331 is projected on the reference plane formed by the static end 31 to form a regular hexagon distribution, the inclination angle of the inclined slide rail 331 relative to the reference plane formed by the static end 31 is 20°-50°, different inclination angles have different motion space ranges to adapt to different requirements.

[0154] The first connecting mechanism 3 described above is also a six-degree-of-freedom parallel movement mechanism, the sliding block 332 slides along the inclined slide rail 331 to drive the end of the actuating rod 334 to synchronously slide along the inclined slide rail 331, the six-degree-of-freedom movement of the dynamic end 32 in the three-dimensional space is realized through the cooperation of the sliding blocks 332 on the six movable members 33 along the inclined slide rails 331, so that the dynamic end 32 can perform translation and deflection actions relative to the static end 31, so that the first connecting mechanism 3 described above is applied to the in-pipe welding machine, and the controllable deflection of the machine head 1 relative to the machine body 2 can also be realized, so that the in-pipe welding machine as a whole becomes curved, thereby being capable of passing through the curved pipe section of the pipeline, and the bending passing ability of the in-pipe welding machine is improved.

[0155] The first connecting mechanism can be a parallel kinematic mechanism or a serial kinematic mechanism, and the first connecting mechanism can have only two controllable active degrees of freedom, three active degrees of freedom, etc. For the parallel kinematic mechanism, various active degrees of freedom can be achieved by designing the number of active members parallelly connected between the static end and the dynamic end, the specific structure of the active members, and the connection relationship between the active members and the static end and the dynamic end. The specific structures of the active members in Embodiment I and Embodiment II are different, but both achieve six degrees of freedom. For example, three active members can be parallelly arranged between the static end and the dynamic end, and the active members specifically adopt linear telescopic members, two ends of two linear telescopic members are connected to the static end and the dynamic end through universal joints respectively, and two ends of the third linear telescopic member are hingedly connected to the static end and the dynamic end respectively. The first connecting mechanism with such a structure has three active degrees of freedom, including two moving degrees of freedom and one rotating degree of freedom. Of course, the active members can also be arranged in other numbers, and the active members can also adopt other types of structures, thereby forming a multi-degree-of-freedom kinematic mechanism meeting the needs. For the serial kinematic mechanism, various active degrees of freedom can be achieved by setting the number of joints and the connection relationship of the joint members.

[0156] When only overbending needs to be achieved through the first connecting mechanism, the first connecting mechanism can have only two controllable active degrees of freedom. Figure 6 The two active degrees of freedom can be rotating degrees of freedom around the x and y axes respectively, rotating degrees of freedom around the x and z axes respectively, or rotating degrees of freedom around the y and z axes respectively. Specifically, when the body of the pipe internal welding machine keeps a posture of not rotating relative to the pipe and travels along the pipe axis, the first connecting mechanism having only two controllable active degrees of freedom can deflect the machine head in any direction to pass through the pipe bent in any direction, for example, the pipe is bent around the y axis. When the two active degrees of freedom of the first connecting mechanism are rotating degrees of freedom around the x and y axes respectively, the first connecting mechanism can achieve overbending by adjusting the posture of the machine head through the rotating activity around the y axis. When the two active degrees of freedom of the first connecting mechanism are rotating degrees of freedom around the x and z axes respectively (the first rotating axis is along the x axis, and the second rotating axis is along the z axis), the first connecting mechanism can first change the first rotating axis of the first connecting mechanism from the x axis direction to the y axis direction through the rotating activity around the z axis through the second rotating axis, and then the first rotating axis of the first connecting mechanism can perform the rotating activity around the y axis, so that the machine head can also be deflected around the y axis to achieve overbending. When the body of the pipe internal welding machine can rotate relative to the pipe, the first connecting mechanism only needs to have one rotating degree of freedom (the rotating axis is along the x-y plane) to achieve passing through the pipe bent in any direction.

[0157] When the alignment is needed to be achieved through the first connecting mechanism, the first connecting mechanism can include three controllable active degrees of freedom, which can be a moving degree of freedom in the z-axis direction and rotating degrees of freedom around the x-axis and y-axis respectively, so that the deflection posture of the head relative to the body can be adjusted through the rotating degrees of freedom around the x-axis and y-axis, preferably so that the central axis of the welding mechanism on the head coincides with the central axis of the pipe to achieve the coaxial state, and the moving degree of freedom in the z-axis direction can move the head in the axial direction of the pipe end, so that the welding mechanism on the head can accurately face the weld center between the two pipes to be connected, thereby realizing accurate alignment on the curved pipe section of the pipe; the three active degrees of freedom can also include the moving degree of freedom in the z-axis direction and rotating degrees of freedom around the y-axis and z-axis respectively, which can also realize accurate alignment; when the body of the pipe internal welding machine itself can rotate relative to the pipe, the first connecting mechanism only needs the moving degree of freedom in the z-axis direction and one rotating degree of freedom (the rotating axis is along the x-y plane) to meet the needs of alignment adjustment.

[0158] Embodiment Three

[0159] As shown in Figure 1 and Figure 2 , on the basis of embodiment one or embodiment two, a sensor 4 for detecting the pipe is further arranged on the head 1, the control system receives the data collected by the sensor 4 and analyzes and processes to obtain control parameters, and the first connecting mechanism 3 acts according to the control parameters to adjust the pose of the head 1. In this embodiment, the sensor 4 is used to automatically control the action of the first connecting mechanism 3, the relative pose relationship between the pipe and the head 1 is obtained by detecting the pipe through the sensor 4, so that the pose of the head 1 relative to the body 2 is automatically adjusted according to the condition of the pipe, the pipe internal welding machine can smoothly pass the bend and accurately perform alignment and welding work, the degree of automation is improved, and the welding quality is guaranteed.

[0160] In this embodiment, the sensor 4 is arranged on the head 1 along the circumference and is spaced apart, as shown in Figure 9As shown, the sensors 4 are specifically provided with three, and the sensors 4 are uniformly distributed along the circumference, the middle axis of the circumference where the sensors 4 are located coincides with the middle axis of the tensioning mechanism 11, that is, the middle axis of the circumference where the sensors 4 are located coincides with the middle axis of the welding mechanism 12. The pipeline is detected by the sensors 4 at multiple positions in the circumferential direction, and the data collected by each sensor 4 is analyzed and processed to more accurately control and adjust the pose of the torch head 1. First, the sensor 4 can be used to detect whether the torch head 1 is located at the middle axis of the welding mechanism 12 and coincides with the middle axis of the pipeline at the position of the welding mechanism 12 (specifically, the pipeline includes a straight pipe section and a curved pipe section, the middle axis of the straight pipe section is linear, and when the welding mechanism 12 is located at the straight pipe section, the middle axis of the welding mechanism 12 coincides with the middle axis of the straight pipe section, and the middle axis of the curved pipe section is curved, and when the welding mechanism 12 is located in the curved pipe section, the middle axis of the welding mechanism 12 actually coincides with the tangent direction of the middle axis of the pipeline at the cross section of the pipeline where the welding mechanism 12 is located, which can be referred to as the middle axis of the welding mechanism 12 coincides with the middle axis of the pipeline). Since the middle axis of the circumference where the sensors 4 are located coincides with the middle axis of the welding mechanism 12, a distance measuring method can be used. When the distances from the three sensors 4 to the inner wall of the pipeline are equal, it can be judged that the middle axis of the welding mechanism 12 coincides with the middle axis of the pipeline at the position of the welding mechanism 12, so that the torch head 1 with the tensioning mechanism 11 is located at the center of the pipeline cross section. During the entire process of the pipeline welding machine traveling along the pipeline, the sensor 4 is used for real-time detection and the first connecting mechanism 3 is used for real-time adjustment of the pose of the torch head 1, so as to maintain the state that the middle axis of the welding mechanism 12 coincides with the middle axis of the pipeline, so that the pipeline welding machine smoothly travels along the pipeline. When the tensioning mechanism 11 on the torch head 1 does not expand outward in the radial direction, the outer diameter size of the torch head 1 as a whole is smaller than the inner diameter of the pipeline. During the traveling process of the pipeline welding machine, the torch head 1 always maintains the state of being located at the center of the pipeline, and the torch head 1 does not contact the inner wall of the pipeline during the traveling process, thereby ensuring the smoothness. When the pipeline welding machine passes through the curved pipe section of the pipeline, the middle axis of the pipeline is bent. Through the detection of the sensor 4 and the automatic adjustment of the first connecting mechanism 3, the middle axis of the welding mechanism 12 coincides with the middle axis of the pipeline at the position of the welding mechanism 12, that is, the torch head 1 deflects relative to the machine body 2, so that the pipeline welding machine as a whole is bent and deformed, thereby smoothly passing through the curved pipe section. During the entire process of passing through the curved pipe section, the torch head 1 maintains the state that the middle axis of the welding mechanism 12 coincides with the middle axis of the pipeline, and the torch head 1 does not collide with the inner wall of the curved pipe section, thereby ensuring the smoothness of passing through the bend.The sensor 4 can also be used for automatic alignment, which refers to accurately aligning the welding mechanism 12 on the head 1 with the center of the weld between the beveled ends of the two pipes to be connected. Specifically, the sensor 4 is used to detect the position of the pipe ends, and then the walking system is controlled to stop the pipe welding machine at a desired position so that the welding mechanism 12 on the head 1 of the pipe welding machine can be aligned with the weld between the two pipes. The walking system has relatively low accuracy, and it is difficult to accurately align the welding mechanism 12 with the center of the weld between the two pipes. Therefore, the walking system can be used in cooperation with the first connecting mechanism 3, that is, the walking system first stops the pipe welding machine at a position with coarse accuracy, at which time the welding mechanism 12 on the head 1 is in the area near the weld between the two pipes, and then the first connecting mechanism 3 drives the head 1 to move for fine adjustment, so that the welding guns of each welding unit of the welding mechanism 12 are accurately aligned with the center of the weld between the beveled ends of the two pipes to be connected, that is, the welding mechanism 12. The degree of automation is high, and human intervention is not required. The alignment accuracy is high, the efficiency is high, and the quality of the welded connection can be improved.

[0161] Specifically, the sensor 4 is a stripe laser displacement sensor. The laser stripe emitted by the sensor 4 is irradiated on the pipe, thereby forming a laser profile line on the pipe. The laser profile line image collected by the sensor 4 is pipe profile data, which is sent to the control system for analysis and processing. The pose of the head 1 relative to the pipe can be obtained, and then the control system analyzes and processes the control parameters and sends them to the first connecting mechanism 3. The first connecting mechanism 3 adjusts according to the control parameters to make the head 1 relative to the pipe reach the required accurate pose.

[0162] More specifically, the control system includes a coaxial unit for analyzing and processing the data collected by the sensor 4 to obtain control parameters for coaxial. The first connecting mechanism 3 moves (specifically, each movable member 33 in the first connecting mechanism 3 moves to make the moving end 32 deflect and / or translate relative to the static end 31) according to the control parameters for coaxial, so that the central axis of the welding mechanism 12 on the head 1 coincides with the central axis of the pipe at the position of the welding mechanism 12 on the pipe. The coaxial unit is used to keep the head 1 in a state where the central axis of the welding mechanism 12 coincides with the central axis of the pipe when the pipe welding machine moves along the pipe, so that when the pipe is bent, the first connecting mechanism 3 automatically drives the head 1 to deflect relative to the body 2 to adapt to the bending of the pipe. The pipe welding machine as a whole becomes curved, and the pipe welding machine maintains the state where the central axis of the welding mechanism 12 coincides with the central axis of the pipe to smoothly pass through the curved pipe section, realizing automatic coaxial passing through the bend.

[0163] Specifically, the walking system on the machine body 2 drives the machine body 2 to move along the pipeline to the side where the machine head 1 is located, the position of the sensor 4 on the machine head 1 is in front of the advancing direction relative to the tensioning mechanism 11 and the welding mechanism 12, in other words, the sensor 4 is farther away from the machine body 2 relative to the tensioning mechanism 11 and the welding mechanism 12, the outgoing direction of the laser stripe of the sensor 4 is toward the side where the tensioning mechanism 11 and the welding mechanism 12 are located, and the outgoing direction of the laser stripe of the sensor 4 is inclined to the axial direction of the tensioning mechanism 11 and toward the radial outer side of the tensioning mechanism 11, and the length direction of the laser stripe of the sensor 4 is in the plane passing through the central axis of the tensioning mechanism 11, further, the irradiation area of the laser stripe of the sensor 4 covers the radial outer side area opposite to the welding mechanism 12, so as to ensure that the pose of the machine head 1 can be detected and accurately adjusted in real time to make the welding mechanism 12 accurately opposite to the center of the weld between the two pipelines.

[0164] The laser stripe emitted by the sensor 4 irradiates on the pipeline to form a laser profile line, when the pose of the machine head 1 relative to the pipeline is different, the laser stripe emitted by the sensor 4 irradiates on the pipeline to form laser profile lines with different shapes. Specifically, when the deflection state of the central axis of the welding mechanism 12 on the machine head 1 relative to the central axis of the pipeline is different, laser profile lines with different shapes are formed, for example, when the machine head 1 is in the straight pipe section of the pipeline, when the central axis of the welding mechanism 12 is completely coincident with the central axis of the pipeline, the laser profile line formed by the laser stripe emitted by the sensor 4 irradiating on the inner wall of the pipeline is a straight line as shown in the shadow area in Figure 10 When there is an angle of deviation between the central axis of the welding mechanism 12 and the central axis of the pipeline, at this time, the length direction of the laser stripe emitted by the sensor 4 is inclined to the axial direction of the pipeline, so that the laser profile line formed by the laser stripe emitted by the sensor 4 on the inner wall of the pipeline is a spiral line as shown in the shadow area in Figure 11 Therefore, the deviation state of the central axis of the welding mechanism 12 relative to the central axis of the pipeline can be judged by analyzing and processing the laser profile line image, which can be matching and comparing the laser profile line image collected by the sensor 4 in real time with the preset profile image (the preset profile image can be specifically a standard laser profile line image formed by the laser stripe irradiating on the inner wall of the pipeline when the central axis of the welding mechanism 12 is completely coincident with the central axis of the pipeline) to obtain the control parameter for the coaxial, and then the first connecting mechanism 3 is automatically controlled to act to keep the machine head 1 in the state that the central axis of the welding mechanism 12 is coincident with the central axis of the pipeline, so that the pipeline internal welding machine can smoothly move along the pipeline and smoothly pass through the curved pipe section, and automatic passing through the bend is realized.

[0165] The cooperation between the first connecting mechanism 3 and the sensor 4 not only realizes the automatic coaxial bending, but also realizes the automatic accurate alignment, which refers to adjusting the pose of the machine head 1 so that the welding mechanism 12 on the machine head 1 is aligned with the weld center between the bevels of the two pipeline ends to be connected. The control system comprises an alignment unit which analyzes and processes the data collected by the sensor 4 to obtain the control parameters for alignment, and the first connecting mechanism 3 acts according to the control parameters for alignment so that the welding mechanism 12 is aligned with the weld center between the two pipelines to be connected. The first connecting mechanism 3 is a multi-degree-of-freedom motion mechanism, which can be a parallel motion mechanism or a serial motion mechanism. The first connecting mechanism 3 can have two to six degrees of freedom, and the specific number of degrees of freedom satisfies the alignment adjustment. The first connecting mechanism 3 has a certain adjustment range, as long as the error between the current position of the welding mechanism 12 on the machine head 1 and the optimal accurate position is less than or equal to the adjustment range of the first connecting mechanism 3, the alignment of the welding mechanism 12 with the weld center between the two pipelines to be connected, that is, the accurate alignment, can be realized through the adjustment action of the first connecting mechanism 3.

[0166] Specifically, as shown in Figure 10 and Figure 12 , the position of the machine head 1 relative to the pipeline end will form different shapes of laser profile lines. Taking the pipeline internal welding machine as an example, the machine head 1 keeps in the state that the central axis of the welding mechanism 12 coincides with the central axis of the pipeline, and walks along the pipeline. When the machine head 1 is completely inside the straight pipe section or the tensioning mechanism 11 and the welding mechanism 12 are still completely inside the straight pipe section, the laser stripe emitted by the sensor 4 is only irradiated on the inner wall of the pipeline, so that the laser profile line formed is a straight line as shown by the shaded area in Figure 10 . When the pipeline internal welding machine continues to walk until the laser stripe emitted by the sensor 4 is irradiated on the bevel of the pipeline end, the laser profile line formed at this time is approximately L-shaped as shown by the shaded area in Figure 12 . The shape of the laser profile line changes, so that the position of the machine head 1 of the pipeline internal welding machine relative to the pipeline end can be judged by analyzing and processing the image of the laser profile line, that is, the image of the laser profile line collected by the sensor 4 in real time can be matched and compared with the preset profile image (the preset profile image can be a standard laser profile line image formed when the laser stripe is irradiated on the pipeline end in the state that the central axis of the welding mechanism 12 coincides with the central axis of the pipeline), so that whether the sensor 4 scans and detects the pipeline end, that is, the distance between the machine head 1 and the pipeline end, can be judged, and then the walking system and the first connecting mechanism 3 can be automatically controlled to cooperate to adjust the machine head 1 to the accurate alignment of the welding mechanism 12 with the weld center between the two pipelines to be connected, so as to finally realize the automatic alignment.

[0167] The aligning unit comprises:

[0168] The scene judging module is configured to analyze and process the data detected and collected by the sensor 4 to determine whether the aligning scene of the pipe end is detected and collected by the sensor 4. When the pipe internal welding machine travels along the pipe through the walking system, the laser stripe emitted by the sensor 4 is irradiated on the pipe to form a laser profile line. When the head 1 of the pipe internal welding machine is at different positions relative to the pipe end, the laser profile line formed by the sensor 4 on the head 1 has different shapes. Specifically, the laser profile line formed when the laser stripe emitted by the sensor 4 is only irradiated on the inner wall of the pipe is different from the laser profile line formed when the laser stripe emitted by the sensor 4 is irradiated on the pipe end. By analyzing and processing the laser profile line image detected and collected by the sensor 4, the position of the head 1 relative to the pipe end can be determined. When the laser stripe is only irradiated on the inner wall of the pipe, it indicates that the welding mechanism 12 on the head 1 is still far away from the pipe end. Therefore, the aligning scene does not occur and the positioning and traveling scene occurs. The pipe internal welding machine continues to travel along the pipe through the walking system. When the laser stripe emitted by the sensor 4 is irradiated on the pipe end, it indicates that the welding mechanism 12 on the head 1 is close to the pipe end. Therefore, the aligning scene occurs and the automatic aligning action is started. Specifically, the sensor 4 detects and collects the pipe profile image. The scene judging module matches and compares the pipe profile image detected and collected by the sensor 4 with a preset image to determine whether the pipe end is detected and collected by the sensor 4. The preset image is a standard profile image containing the pipe end, which is collected by the sensor 4 when the center axis of the welding mechanism 12 coincides with the center axis of the pipe. Therefore, when the pipe profile image detected and collected by the sensor 4 matches the preset image, the head 1 is in the coaxial posture in which the center axis of the welding mechanism 12 coincides with the center axis of the pipe. In other words, when the aligning scene occurs, the head 1 is in the coaxial posture in which the center axis of the welding mechanism 12 coincides with the center axis of the pipe, which is beneficial to the efficiency and accuracy of subsequent aligning adjustment. During the process in which the pipe internal welding machine travels along the pipe through the walking system, the coaxial unit is always in the working state to keep the head 1 in the coaxial posture in which the center axis of the welding mechanism 12 coincides with the center axis of the pipe. Therefore, the state in which the center axis of the welding mechanism 12 coincides with the center axis of the pipe is maintained when the aligning scene occurs.

[0169] The metering module analyzes and processes the data detected and collected by the sensor 4 to obtain the distance from the sensor 4 to the plane where the pipe end is located when the pipe end is in the alignment scene. The sensor 4 detects and collects laser profile line images containing various data information. The relative position information between the pipe end and the sensor 4 can be obtained by analyzing and processing the laser profile line images. The welding mechanism 12 on the head 1 has a fixed position relationship with the sensor 4. That is, the current relative position information between the pipe end and the welding mechanism 12 is obtained. Then, the pose of the head 1 is adjusted by the first connecting mechanism 3 to make the welding mechanism 12 directly face the weld center between the end bevels of the two pipes to be connected.

[0170] The parking module sends an instruction to control the walking system to stop the body 2 when the distance from the sensor 4 to the plane where the pipe end is located reaches the walking stop condition. The walking accuracy of the walking system is low, and it is difficult to make the welding mechanism 12 directly face the weld center between the end bevels of the two pipes to be connected by controlling the walking system to stop the body 2. Therefore, the walking system is used to stop the pipe welding machine at a position with coarse accuracy. At this time, the welding mechanism 12 is in the vicinity of the weld between the end bevels of the two pipes to be connected. Then, the pose of the head 1 is accurately adjusted by the first connecting mechanism 3, so that the welding mechanism 12 can accurately face the weld center between the end bevels of the two pipes to be connected. The alignment efficiency and accuracy are high. More specifically, a plurality of sensors 4 are arranged on the head 1 along the circumference. When the distance from at least two sensors 4 to the plane where the pipe end is located reaches the walking stop condition or when the distance from more than half of the sensors 4 to the plane where the pipe end is located reaches the walking stop condition, the parking module sends an instruction to control the walking system to stop the body 2.

[0171] The alignment fine adjustment module analyzes and processes the data detected and collected by the sensor 4 in the parked state of the body 2 to obtain control parameters for fine adjustment (the control parameters for alignment include the instruction to control the walking system to stop the body 2 and the control parameters for fine adjustment). In the state where the walking system stops the body 2 in the pipe, the first connecting mechanism 3 acts according to the control parameters for fine adjustment (specifically, each movable member 33 in the first connecting mechanism 3 performs corresponding actions to make the moving end 32 deflect and / or translate relative to the static end 31). When the distance from the sensor 4 to the plane where the pipe end is located reaches the preset alignment distance, the first connecting mechanism 3 stops acting. At this time, the welding mechanism 12 accurately faces the weld center between the two pipes to be connected, and the central axis of the welding mechanism 12 coincides with the central axis of the pipe end bevel. The tensioning mechanism 11 expands to the radial outside to tightly fix the pipe. Then, the welding mechanism 12 can perform welding work.

[0172] The aligning method of the pipe internal welding machine is that the walking system drives the whole pipe internal welding machine to move in the pipe, so that the head 1 of the pipe internal welding machine moves from the inside of the pipe to the outside of the pipe end, the control system analyzes and processes the data detected and collected by the sensor 4 to determine whether the sensor 4 detects and collects the pipe end, that is, to determine whether the pipe internal welding machine moves to the aligning scene, and the sensor 4 detects and collects the laser profile line of the pipe. The control system analyzes and processes the laser profile line, which can specifically be that the pipe profile image detected and collected by the sensor 4 is matched and compared with a preset image to determine whether the sensor 4 detects and collects the pipe end. For example, when the laser profile line is a straight line as shown in FIG. 6, it represents that the laser stripe emitted by the sensor 4 is only irradiated on the inner wall of the pipe. At this time, the tensioning mechanism 11 and the welding mechanism 12 on the head 1 are still far away from the end of the pipe, and the pipe internal welding machine is still in the locating and moving scene. Therefore, the walking system continues to normally work to drive the whole pipe internal welding machine to move along the pipe. Figure 10 When the laser profile line becomes L-shaped as shown in FIG. 7, it represents that the laser stripe emitted by the sensor 4 has irradiated on the bevel of the pipe end. In other words, the sensor 4 has detected the pipe end at this time, and the pipe internal welding machine has moved to the aligning scene. Figure 12

[0173] When in the aligning scene, the control system analyzes and processes the pipe profile data (laser profile line image) detected and collected by the sensor 4 to obtain the distance from the sensor 4 to the plane where the pipe end is located, so as to control the position of the walking system to stop the body 2 by the distance from the sensor 4 to the plane where the pipe end is located.

[0174] The walking system continues to normally work to drive the whole pipe internal welding machine to move along the pipe, and the head 1 further moves to the outside of the pipe end. The distance from the sensor 4 to the plane where the pipe end is located will continue to increase. When the distance from the sensor 4 to the plane where the pipe end is located reaches the walking stopping condition (the walking stopping condition can be a specific preset distance value, which is a set value and can be set according to specific conditions), the walking system stops the body 2, that is, the body 2 of the pipe internal welding machine is stopped in the inside of the pipe. At this time, the welding mechanism 12 on the head 1 is in the area range close to the weld joint between the two pipes. Specifically, when the distance from the sensor 4 to the plane where the pipe end is located exceeds a preset distance value, the walking system stops the body 2. Preferably, the walking stopping condition is set to be that when the walking system stops the body 2, the welding mechanism 12 is still on the inside of the pipe end, so that the head 1 needs to continue to move to the outside of the pipe end under the adjusting action of the first connecting mechanism 3 to make the welding mechanism 12 face the center of the weld joint between the two pipes to be butt-jointed.

[0175] ​In the state that the walking system has stopped the body 2, the control system analyzes and processes the laser profile image detected by the sensor 4 at this time to obtain the control parameter, and the first connecting mechanism 3 acts according to the control parameter to drive the head 1 to fine-tune, and when the distance between the sensor 4 and the plane where the pipe end is located reaches the preset butt distance, the first connecting mechanism 3 stops acting (the accurate automatic butt is realized by accurately controlling the distance between the sensor 4 and the plane where the pipe end is located, and the distance between the welding mechanism 12 and the sensor 4 in the axis direction of the tensioning mechanism 11 is definite and fixed, so the preset butt distance is actually equal to the distance between the welding mechanism 12 and the sensor 4 in the axis direction of the tensioning mechanism 11 plus half of the gap between the end bevels of the two pipes, and when the distance between the sensor 4 and the plane where the pipe end is located reaches the preset butt distance, it can be determined that the welding torch of each welding unit of the welding mechanism 12 is accurately opposite to the weld center between the end bevels of the two pipes to be butt-jointed, and the accurate automatic butt is realized), and specifically, the three sensors 4 are uniformly arranged along the circumference, and when the distance between the three sensors 4 and the plane where the pipe end is located reaches the preset butt distance, the welding mechanism 12 is accurately opposite to the weld center between the two pipes to be butt-jointed, and the automatic butt action process is completed.

[0176] In the automatic butt process, the state that the central axis of the welding mechanism 12 on the head 1 coincides with the central axis of the pipe is maintained, that is, in the process that the walking system drives the pipe internal welding machine to travel in the pipe, the control system always analyzes and processes the data detected by the sensor 4 to obtain the control parameter for coaxiality, the first connecting mechanism 3 acts according to the control parameter for coaxiality to maintain the head 1 in the state that the central axis of the welding mechanism 12 coincides with the central axis of the pipe, and the state that the central axis of the welding mechanism 12 coincides with the central axis of the pipe is also maintained in the process that the first connecting mechanism 3 drives the head 1 to fine-tune after the walking system stops the body 2, and the state that the central axis of the welding mechanism 12 coincides with the central axis of the pipe is also required after the automatic butt is completed, so that the tensioning mechanism 11 can be evenly and stably expanded to the radial outside to tension and fix the pipe, and then the welding mechanism 12 can accurately weld the weld between the two pipes to be butt-jointed.

[0177] In addition to the foregoing specific sensor structure, other sensor structures can also be used, such as replacing the foregoing stripe laser displacement sensor with a distance sensor, a vision system, etc. The sensor can also be arranged in other ways or at other positions, such as being arranged on the machine body 2. For example, a circular track is arranged on the machine head 1, the central axis of the circular track coincides with the central axis of the welding mechanism 12, and the sensor is arranged on the circular track to move along the circular track. The sensor can stop at any position on the circular track and detect the pipe, so as to detect data at any position on the entire circumference of the pipe, improve the detection accuracy, and have better flexibility and applicability.

[0178] Embodiment Four

[0179] As shown in Figure 1 , Figure 2 and Figure 13 , on the basis of Embodiment One, the walking system on the machine body 2 specifically includes a traveling mechanism 51, the traveling mechanism 51 includes a plurality of walking wheel assemblies 511 arranged at intervals along the circumference of the machine body 2, the walking wheel assemblies 511 are connected to a clamping mechanism 512 arranged on the machine body 2, the walking wheel assemblies 511 are driving wheel mechanisms for driving the machine body 2 to travel inside the pipe, and the clamping mechanism 512 is used to press the walking wheel assemblies 511 against the inner wall of the pipe, so that there is enough friction between the walking wheel assemblies 511 and the inner wall of the pipe, thereby avoiding the situation that the walking wheel assemblies 511 slip or slide when operating, improving the climbing ability of the pipe internal welding machine, and being suitable for large slope inclined pipe sections.

[0180] Specifically, the walking wheel assemblies 511 are arranged at two sides in the diameter direction of the machine body 2, and the clamping mechanism 512 is a clamping hydraulic cylinder connected between the two walking wheel assemblies 511. The clamping hydraulic cylinder is connected to the machine body 2, and the extension and retraction of the clamping hydraulic cylinder drives the walking wheel assemblies 511 to move along the diameter direction of the machine body 2, thereby pressing the walking wheel assemblies 511 against the inner wall of the pipe. The structure is simple and compact, the clamping hydraulic cylinder uses hydraulic pressure to provide clamping force, and the clamping force can be improved without increasing the volume, thereby better avoiding the situation that the walking wheel assemblies 511 slip or slide when operating, improving the climbing ability, and improving the safety and reliability of the pipe internal welding machine when traveling inside the pipe.

[0181] Further, each walking wheel assembly 511 is provided with a walking motor 513, which is a motor with a brake. Compared with a traditional pneumatic motor, the walking motor 513 has greater power and can be self-locked through the brake. When the walking motor 513 is self-locked through the brake, the wheels of the walking wheel assembly 511 cannot rotate, thereby providing an additional layer of protection for the pipe internal welding machine to stop at an inclined pipe section of the pipeline. Since each walking wheel assembly 511 is provided with an independent walking motor 513, the walking wheel assemblies 511 on both sides can work relatively independently, that is, the walking speeds of the walking wheel assemblies 511 on both sides can be different, so that differential speed overbending can be realized when passing through a curved pipe section. Specifically, the walking speeds of the walking wheel assemblies 511 on both sides are controlled in an electronic differential control mode when overbending. The radii of the inner bending side and the outer bending side of the curved pipe section are different, and the walking wheel assembly 511 on the outer bending side needs to rotate at a higher speed than the walking wheel assembly 511 on the inner bending side to smoothly overbend.

[0182] Specifically, when the pipe internal welding machine overbends, if the control parameters of the two walking motors are consistent, the rotation speed of the walking wheel assembly on the outer bending side is consistent with that of the walking wheel assembly on the inner bending side. In the speed control mode of the motor drive, the speed control mode requires the speed to be constant. If the speeds of the two motors do not change at this moment, the resistance experienced by the wheels of the walking wheel assembly on the outer bending side is different from that experienced by the wheels of the walking wheel assembly on the inner bending side. To keep the motor speed constant, the driving force provided by the drivers of the walking motors on the outer bending side and the inner bending side needs to be different. The driving force provided by the drivers of the two walking motors can read this small difference, and this torque difference is used as an input feedback. Through PID adjustment, the running speeds of the walking wheel assembly on the outer bending side and the walking wheel assembly on the inner bending side can be adjusted in real time, so that differential speed overbending of the inner and outer wheels is realized, and the stable operation of the equipment is ensured. Unlike the traditional pipe internal welding machine, which is easily stuck at the curved pipe section because the wheels on the inner and outer bending sides do not have differential speed, the walking motor needs to overcome a large clamping force to forcibly pass through, which is easy to cause damage to the equipment.

[0183] Further, as shown in FIG. 6, the walking wheel assembly 511 is provided with a walking wheel 512, and the walking wheel 512 is provided with a plurality of wheels. The walking wheel 512 is provided with a plurality of wheels, and the walking wheel 512 is provided with a plurality of wheels. Figure 1 、 Figure 2 and Figure 14As shown, the walking system further comprises a brake mechanism 52, which specifically comprises a brake cylinder 521, a brake pad 522 and a retaining elastic member 523. The brake cylinder 521 is connected to the machine body 2. The brake pad 522 is driven by the brake cylinder 521 to switch between a braking position and a release position. When the brake pad 522 is in the braking position, the brake pad 522 is pressed against the inner wall of the pipeline by the brake cylinder 521 to achieve reliable braking, ensuring that the pipeline internal welding machine stops stably in the pipeline. Even if the pipeline section is inclined, the vehicle will not slip, improving safety and reliability. When the brake pad 522 is in the release position, the brake pad 522 is separated from the inner wall of the pipeline. At this time, the pipeline internal welding machine can reliably travel along the inside of the pipeline under the drive of the walking mechanism 51. The brake pad 522 is also connected to the retaining elastic member 523 for driving the brake pad 522 to remain in the braking position. Even if the brake cylinder 521 is damaged and does not work, the brake pad 522 can still remain in the state of abutting against the braking position in the pipeline under the action of the retaining elastic member 523, avoiding the condition of slipping. Only when the brake cylinder 521 is normal and actively retracts the brake pad 522 to the release position can the braking condition be cancelled. The retaining elastic member 523 is specifically a gas spring. The speed is relatively slow, the dynamic force changes little, it is easy to control, has an almost linear elastic curve, and the pressing force applied to the brake pad is more stable, ensuring the stability of the brake.

[0184] Further, as shown in Figure 1 and Figure 15 The walking system comprises a flexible wheel assembly 53 arranged near the front of the machine body 2. The front of the machine body 2 refers to the side close to the machine head 1. The walking wheel assembly 511 is arranged in the middle of the machine body 2. The rear of the machine body 2 is also provided with a rear wheel 54. The flexible wheel assembly 53 and the rear wheel 54 are driven wheels. The machine body 2 is supported on the inner wall of the pipeline by the flexible wheel assembly 53, the walking wheel assembly 511 and the rear wheel 54, so that the machine body 2 can reliably travel along the inside of the pipeline.

[0185] The flexible wheel assembly 53 specifically includes a wheel 531, a wheel seat 532, and an elastic component 533. The wheel 531 is mounted on the wheel seat 532, which is hinged to the machine body 2. The rotation plane of the wheel seat 532 is along the radial direction of the machine body 2. The elastic component 533 is connected between the wheel seat 532 and the machine body 2. The elastic component 533 is specifically a flexible spring. The wheel 531 in the flexible wheel assembly 53 can buffer and expand relative to the machine body 2 in the radial direction of the machine body 2 through the wheel seat 532 hinged to the machine body 2. When the pipe welding machine is subjected to external force, such as when the tensioning mechanism works against the inner wall of the pipe or when the machine head 1 contacts and collides with the inner wall of the pipe, the wheel 531 can deflect relative to the machine body 2 along with the wheel seat 532, thereby causing the elastic component to undergo elastic deformation. The elastic component buffers and absorbs the impact force, which can prevent the pipe welding machine from being damaged by impact and effectively protect the pipe welding machine.

[0186] Furthermore, the flexible wheel assembly 53 also includes an angle adjustment motor 534 connected to the wheel 531 and mounted on the wheel seat 532. The angle adjustment motor 534 adjusts the direction of travel of the wheel 531. During the process of the pipe welding machine traveling along the inner wall of the pipe, it is difficult to ensure that the posture of the pipe welding machine remains constant. Inevitably, the pipe welding machine will rotate relative to the pipe. For example, when the pipe welding machine is traveling in a horizontal pipe, if the pipe welding machine rotates clockwise to the left, the angle adjustment motor 534 can be used to adjust the direction of the wheel 531, so that the wheel 531 rotates to the right by a certain angle, thereby guiding the pipe welding machine to rotate counterclockwise to the right to return to the normal posture. A gyroscope can be installed on the body 2 of the pipe welding machine to monitor the posture of the body 2 based on the information from the gyroscope, and then control the angle adjustment motor 534 to drive the wheel 531 to turn in order to adjust and control the posture of the pipe welding machine.

[0187] Example 5

[0188] like Figure 1 As shown in Embodiment 4, the pipe welding machine further includes a battery unit 6 integrated on the machine body 2. The battery unit 6 supplies power to the tensioning mechanism 11, welding mechanism 12, walking system, and first connecting mechanism 3. It achieves high efficiency and energy saving through a power distribution management system, rationally managing and distributing power. The battery unit 6 uses lithium batteries and is managed by a BMS system to improve safety. The battery unit 6 also includes a heating component to heat the battery unit 6 when it is at a low temperature, improving its operational safety and reliability. Fast charging ensures charging is completed within 1.5 hours, greatly facilitating on-site construction.

[0189] The pipe welding machine also includes a welding power source 7 integrated on the machine body 2, eliminating the delivery rod of traditional internal welding machines and greatly facilitating on-site construction. The welding power source 7 integrates multiple traditional welding power sources, which have three or four positive welding cables and one negative welding cable. It is powered by the battery unit 6 built into the pipe welding machine, and the welding power source 7 is electrically connected to the welding unit of the welding mechanism 12 via the welding cables.

[0190] Furthermore, the body 2 also integrates a hydraulic system 8, which provides hydraulic power to the tensioning mechanism 11, the braking mechanism 52, and the clamping mechanism 512 of the traveling mechanism 51, such as... Figure 16 As shown, the hydraulic system 8 includes a front tensioning cylinder 81, a rear tensioning cylinder 82, a traveling cylinder 83, and a brake cylinder 521 arranged in parallel. The front tensioning cylinder 81 corresponds to the front tensioning component 111 of the tensioning mechanism 11, and the rear tensioning cylinder 82 corresponds to the rear tensioning component 112 of the tensioning mechanism 11, to achieve tensioning and fixing of the pipeline. The traveling cylinder 83 corresponds to the clamping mechanism 512 of the traveling mechanism 51, so that the traveling wheel assembly 511 can be tightly pressed against the inner wall of the pipeline to ensure stability. A reversing valve is connected to each of the front tensioning cylinder, rear tensioning cylinder, traveling cylinder, and brake cylinder. The hydraulic system 8 flexibly controls the action state of each cylinder to achieve the function of each component. The machine body 2 also integrates a protective gas cylinder 9, which provides protective gas to the welding mechanism 12 to ensure welding quality.

[0191] Example 6

[0192] like Figure 17 As shown in Embodiment 5, the body 2 can be divided into several sections along the pipeline axis. Adjacent sections are connected by a second connecting mechanism 10. The second connecting mechanism 10 is a deflectable connecting mechanism. Specifically, the second connecting mechanism 10 can also adopt the same structure as the first connecting mechanism 3 described in Embodiment 1. That is, the second connecting mechanism 10 can be an actively controllable movable connecting mechanism. However, compared with the head 1 which has a tensioning mechanism 11 and a welding mechanism 12, the high precision required for attitude control of the sections of the body 2 is relatively low. It is only necessary for the sections of the body 2 to be able to deflect relative to each other to improve the bending performance. Therefore, the second connecting mechanism 10 can be a passive movable connecting mechanism.

[0193] Specifically, the body 2 in the embodiment only contains two segments, and the second connecting mechanism 10 between the two segments includes a first end 101, a second end 102, a universal joint 103, and a plurality of flexible connecting members 104 distributed in the circumferential direction of the universal joint 103, the first end 101 is connected with the previous segment, and the second end 102 is connected with the next segment. The second connecting mechanism 10 has a simple structure and is easy to implement. The second connecting mechanism can passively deflect without active adjustment. When the pipe internal welding machine passes through the curved pipe segment, each segment of the body 2 contacts the inner wall of the pipe. Under the abutting force of the inner wall of the pipe on each segment, the adjacent segments deflect relative to each other through the second connecting mechanism to match the bending radius of the curved pipe segment, so that each segment of the body 2 changes from the original linear arrangement to the curved arrangement. The curved shape of the body 2 at this time matches the bending radius of the curved pipe segment, so that the pipe internal welding machine can smoothly pass through the curved pipe segment, further improving the bending passing ability of the pipe internal welding machine.

[0194] Further, the body 2 is divided into two segments, and modules with different functions can be integrated on the same segment according to similar categories. The segment close to the head 1 is mainly provided with a walking system and a battery unit. Specifically, the segment close to the head 1 is provided with a traveling mechanism 51, a brake mechanism 52, a flexible wheel assembly 53, and a rear wheel 54, etc. The segment away from the head 1 is mainly an energy segment, and is mainly provided with a protection gas cylinder 9, a welding power supply 7, and a hydraulic oil tank, etc.

[0195] Posture adjusting system of internal welding machine

[0196] The embodiment of the present application provides an internal welding machine posture adjusting system, which comprises a posture adjusting device 204, an electrical control module and a sensor 4, and the posture adjusting device 204 is arranged between a first segment 201 and a second segment 205 of the internal welding machine. The electrical control module can control the posture adjusting device 204 to adjust the posture of the internal welding machine according to the data collected by the sensor 4. Specifically, the posture adjusting device 204 can be arranged between any two segments of the internal welding machine, and each segment can be a rigid non-rotatable component or can be additionally designed with a hinged structure in the segment. As a preferred embodiment of the present application, as shown in the figure, the first segment 201 is a cone head mechanism, and the cone head mechanism is provided with electrical elements, a tensioning assembly 203 and a welding mechanism; the second segment 205 is a body mechanism, and the body mechanism is provided with a walking device, a brake device, a driving device, etc. Figure 18

[0197] ​The posture adjusting device 204 comprises a moving platform 2041, a fixed platform 2043, a linear driving mechanism 2042 and a universal joint. The moving platform 2041 is in an integral structure with the rack of the first sub-section 201, the fixed platform 2043 is in an integral structure with the rack of the second sub-section 205, and the two ends of the linear driving mechanism 2042 are connected with the moving platform 2041 and the fixed platform 2043 through the universal joint respectively. One linear driving mechanism 2042 corresponds to two universal joints, that is, the first end of the linear driving mechanism 2042 is connected with the moving platform 2041 through one universal joint, and the second end of the linear driving mechanism 2042 is connected with the fixed platform 2043 through another universal joint. Further, the posture adjusting device 204 is a six-degree-of-freedom motion platform 2041 comprising six linear driving mechanisms 2042. For the posture adjusting device 204 arranged between any two sub-sections of the internal welding machine, the active driving of the posture adjusting device 204 can be detected through the sensor 4, that is, the side connected with the moving platform 2041 can adapt to the pipe contour to enable the internal welding machine to freely walk in the pipe without collision. For the above preferred embodiment, the moving platform 2041 is installed on one side of the taper head mechanism, that is, the moving platform 2041 is located close to the tensioning assembly 203 and the welding device 202, so that the posture adjusting device 204 can flexibly adjust the taper head mechanism (including the tensioning assembly 203 and the welding device 202) to make the head of the internal welding machine more adapt to the pipe.

[0198] The sensor 4 can be used to collect the pipe contour data of the position where the internal welding machine is located, and the posture adjusting device 204 can comprise a plurality of sensors 4 to collect comprehensive pipe contour data.

[0199] An electrical control module is used to calculate the target posture of the first sub-section 201 according to the pipe contour data, and to generate a length change signal of the linear driving mechanism 2042 through the calculation of the motion inverse algorithm of the target posture. The electrical control module is also used to control the linear driving mechanism 2042 to perform the extension and contraction movement through the length change signal, so that the first sub-section 201 is in the target posture. Specifically, the current relative position between the pipe and the internal welding machine can be determined according to the pipe contour data, and the target posture of the first sub-section 201 can be determined according to the above current relative position. The target posture can be the posture that enables the internal welding machine to normally travel in the pipe without collision.

[0200] The posture adjusting device 204 provided by the embodiment is arranged between the first section 201 and the second section 205 of the internal welding machine. Since the moving platform 2041 is in an integrated structure with the rack of the first section 201, and the fixed platform 2043 is in an integrated structure with the rack of the second section 205, when the linear driving mechanism 2042 of the posture adjusting device 204 performs the extension and retraction movement, the posture of the first section 201 can be changed. In the working process of the electrical control module in the embodiment, the target posture of the first section 201 is calculated according to the pipe profile data, and the length change signal of the linear driving mechanism is generated by performing the motion inverse algorithm calculation on the target posture, and then the linear driving mechanism 2042 is controlled to perform the extension and retraction movement through the length change signal, so that the first section 201 is in the target posture. The embodiment can realize the automatic posture adjustment of the internal welding machine according to the pipe profile data, and improve the welding quality.

[0201] As a feasible implementation, the posture adjusting system includes a plurality of sensors 4, all the sensors 4 are uniformly distributed on the first section 201, all the sensors 4 are in the same plane, the installation positions of all the sensors 4 are approximately in a plane, the plane is perpendicular to the axis of the first section 201, and the sensors 4 are arranged towards the tensioning assembly 203. For example, the posture adjusting device 204 can include three sensors 4, each sensor 4 is distributed on the first section 201 at an interval of 120°, and is arranged towards the pipe area on the peripheral side of the tensioning assembly 203.

[0202] As a feasible implementation, the posture adjusting device 204 of the posture adjusting system further includes a moving end mounting seat 2044 and a fixed end mounting seat 2045, and the universal joint includes a first type of universal joint and a second type of universal joint. The moving end mounting seat 2044 is fixed to the moving platform 2041 by bolts, the first type of universal joint is fixed to the moving end mounting seat 2044 by bolts, and the first end of the linear driving mechanism 2042 is connected to the first type of universal joint by bolts. The fixed end mounting seat 2045 is fixed to the fixed platform 2043 by bolts, the second type of universal joint is fixed to the fixed end mounting seat 2045 by bolts, and the second end of the linear driving mechanism 2042 is connected to the second type of universal joint by bolts.

[0203] As a feasible implementation, the above-mentioned electrical control module includes a motion controller, a servo driver and a servo motor. The motion controller is configured to calculate a target pose of the first sub-section 201 according to the pipe profile data, and to generate a length change signal of the linear drive mechanism 2042 by performing a motion inverse algorithm on the target pose. The servo driver is configured to generate a corresponding pulse signal according to the length change signal issued by the motion controller. The servo motor is configured to rotate according to the pulse signal issued by the servo driver, so as to drive the corresponding linear drive mechanism 2042 to perform a telescopic motion until the first sub-section 201 is in the target pose.

[0204] Figure 18 The sensor 4 installed on the first sub-section 201 of the integrated intelligent pipe internal welding machine shown in the figure detects the pipe profile data and transmits the pipe profile data to the motion controller. The motion controller calculates the telescopic length of each linear drive mechanism 2042 in the pose adjusting device 204, so as to control the action of the moving platform 2041, thereby achieving the effect of active bending of the first sub-section 201 of the internal welding machine head.

[0205] Figure 19 The pose adjusting system shown in the figure includes a sensor 4, an Ethernet line, a controller area network (CAN), an electrical control cabinet, a motion controller, a digital module, other expansion modules, a direct current (DC) power supply, a servo driver, a control system, and a pose adjusting device 204. The pose adjusting device 204 can include a moving platform 2041, a universal joint, a linear drive mechanism 2042, and a fixed platform 2043, as shown in the figure. The control system includes a control cabinet (which can be distributed on the internal welding machine), a multi-axis motion controller, a driver, and a servo motor. Figure 20

[0206] The working principle of the above-mentioned pose adjusting device 204 is as follows: the sensor 4 detects the pipe profile data, and then transmits the pipe profile data to the control system. The control system converts the pipe profile data into a length change signal of the linear drive mechanism 2042 by using a motion inverse algorithm, and sends a driving signal to the servo driver through the motion controller, so as to drive the servo motor, so that the linear drive mechanism 2042 performs a telescopic motion according to the given length change. The linear drive mechanism 2042 drives the moving platform 2041 to change the pose through the mechanism connected with the moving platform 2041 and the fixed platform 2043, so that the moving platform 2041 moves according to the trajectory of the pipe bending change.

[0207] Figure 21 The flowchart of the pose adjusting method of the internal welding machine provided in the embodiments of the present application can include the following specific steps:

[0208] ​S301: Obtain the pipe profile data of the first sub-section 201 of the inner welding machine;

[0209] In combination Figure 18 The inner welding machine comprises a first sub-section 201, a second sub-section 205 and a pose adjusting device 204, the first sub-section 201 is provided with a sensor 4 for detecting the pipe profile data near the movable platform 2041. For some preferred embodiments of the system, the pose adjusting device 204 is arranged between the taper head mechanism and the body mechanism, so that the movable platform 2041 is adjacent to the tensioning assembly 203, and the sensor 4 detects the pipe profile data near the tensioning assembly 203 and the welding device 202.

[0210] The pose adjusting device 204 is arranged between the first sub-section 201 and the second sub-section 205, and comprises a movable platform 2041, a fixed platform 2043, a linear drive mechanism 2042 and a universal joint, the movable platform 2041 is connected to the frame of the first sub-section 201, the fixed platform 2043 is connected to the frame of the second sub-section 205, and the two ends of the linear drive mechanism 2042 are respectively hinged to the movable platform 2041 and the fixed platform 2043.

[0211] In a preferred embodiment, the sensor 4 is a stripe laser sensor, the laser stripe emitted by the sensor 4 is irradiated on the pipe to form a laser profile line on the pipe, and the image of the laser profile line is collected for analysis and processing, so as to determine whether the sensor 4 detects the pipe end face;

[0212] More specifically, the walking device on the second sub-section 205 drives the second sub-section 205 to move along the pipe towards the side where the first sub-section 201 is located, the position of the sensor 4 on the taper head mechanism is in front of the tensioning assembly 203 and the welding device 202 in the moving direction, in other words, the sensor 4 is farther away from the second sub-section 205 relative to the tensioning assembly 203 and the welding device 202, the emission direction of the laser stripe of the sensor 4 is towards the side where the tensioning assembly 203 and the welding device 202 are located, and the emission direction of the laser stripe of the sensor 4 is inclined to the axial direction of the tensioning assembly 203 and towards the radial outer side of the tensioning assembly 203, and the length direction of the laser stripe of the sensor 4 is in the plane passing through the central axis of the tensioning assembly 203, further, the irradiation area of the laser stripe of the sensor 4 covers the radial outer side area opposite to the welding device 202, so as to ensure that the pose of the first sub-section 201 can be adjusted in real time and accurately to make the welding device 202 accurately opposite to the weld center between the two pipes.

[0213] The laser stripe emitted by the sensor 4 irradiates on the pipeline to form a laser profile line. The position and posture of the first sub-section 201 relative to the pipeline are different, and the laser stripe irradiates on the pipeline to form a laser profile line with different shapes. Specifically, the deflection state of the central axis of the tensioning assembly 203 on the first sub-section 201 relative to the central axis of the pipeline is different, which forms a laser profile line with different shapes. For example, when the first sub-section 201 is in a straight pipe section of the pipeline, when the central axis of the tensioning assembly 203 coincides with the central axis of the pipeline, the laser profile line formed by the laser stripe emitted by the sensor 4 on the inner wall of the pipeline is a straight line. When there is an angle of deviation between the central axis of the tensioning assembly 203 and the central axis of the pipeline, the length direction of the laser stripe emitted by the sensor 4 is inclined to the axis direction of the pipeline, so that the laser profile line formed by the laser stripe emitted by the sensor 4 on the inner wall of the pipeline is an arc.

[0214] More specifically, the laser profile lines formed by the three sensors 4 are sent to the controller, the control system analyzes the images of the laser profile lines formed by the sensors 4 to obtain corresponding control parameters, and the posture adjusting device 204 acts according to the control parameters for centering to maintain the first sub-section 201 in a state that the central axis of the tensioning assembly 203 coincides with the central axis of the pipeline, that is, to maintain the first sub-section 201 in the center of the pipeline cross section, so as to ensure that the internal welding machine smoothly travels along the inner wall of the pipeline.

[0215] The sensor 4 for detecting the profile data can also be implemented by a laser ranging sensor, an image sensor or the like arranged on the internal welding machine. In other possible embodiments, the sensor 4 can be arranged on the taper head mechanism, or on or near part or all of the tensioning units of the tensioning assembly 203 or the welding device 202. Of course, considering the timeliness of the posture adjustment, it is more optimal to arrange the sensor 4 near the advancing direction of the internal welding machine, and arranging the detection area of the sensor 4 near the tensioning units or the welding device 202 can better guarantee the effectiveness of the posture adjustment.

[0216] If the central axes of the uniformly distributed tensioning units and the welding device 202 deviate from the central axis of the pipeline, different image sensors and laser ranging sensors will detect different feedback results. Through the corresponding signal changes detected by the sensors, the internal welding machine can be adjusted in real time, and the posture adjustment can be realized.

[0217] S302: calculating a target posture of the first sub-section 201 according to the pipeline profile data, and generating an adjustment signal based on the target posture;

[0218] In combination Figures 18 to 20 , specifically comprising:

[0219] Based on the known sensor installation correction coefficient, the profile data scanned by each sensor 4 is transformed into corrected profile data in the first section 201 coordinate system;

[0220] Based on the corrected profile data, the position and pose of the current pipe in the first section 201 coordinate system are calculated;

[0221] The pipe mathematical model is solved to obtain the pipe pose information of the current pipe in the first section 201 coordinate system;

[0222] The pose (i.e., the deflection angle relative to the first section 201) and position (i.e., the offset relative to the first section 201) between the pipe and the first section 201 are obtained, and an adjustment signal is generated.

[0223] Furthermore, since the sensors 4 and the tensioning assembly 203 and the welding device 202 are at a distance in the pipe axis direction, in order to ensure accuracy, the measurement error of the sensors 4 also needs to be corrected. In this embodiment, the sensor installation correction coefficient is a homogeneous transformation matrix composed of each installation design size and the actual installation error measurement value of each sensor 4. By multiplying the profile data scanned by each sensor 4 by the homogeneous transformation matrix, the profile data of each sensor 4 can be transformed into the first section 201 coordinate system.

[0224] Further, the pipe profile data collected by each sensor 4 is converted in the first section 201 coordinate system; then, based on the corrected profile data, the position and pose of the current pipe in the first section 201 coordinate system are calculated using an optimal fitting algorithm;

[0225] The pipe mathematical model is solved using the optimization objective function of the least squares method to obtain the pipe pose information of the current pipe in the first section 201 coordinate system.

[0226] S303: Based on the adjustment signal, the linear drive mechanism 2042 is driven to make the axis of the moving platform 2041 on the first section 201 be in the target pose.

[0227] As Figures 18 to 21The posture adjusting device 204 provided in the embodiment is arranged between the first section 201 and the second section 205 of the internal welding machine, and when the linear driving mechanism 2042 of the posture adjusting device 204 performs the extension and retraction movement, the posture of the first section 201 can be changed. In the embodiment, the electrical control module calculates the target posture of the first section 201 according to the pipe profile data in the working process, and generates the length change signal of the linear driving mechanism 2042 through the calculation of the motion inverse algorithm of the target posture, and then controls the linear driving mechanism 2042 to perform the extension and retraction movement through the length change signal, so that the first section 201 is in the target posture. The embodiment can realize the automatic posture adjustment of the internal welding machine according to the pipe profile data, and improve the welding quality.

[0228] The target posture is in the most ideal state, in which the central axis of the movable platform 2041 coincides with the central axis of the pipe section where the movable platform 2041 is located, and at this time, the first section 201 of the internal welding machine passes through the linear driving mechanism 2042 to adapt to the pipe without collision and interference. In the actual situation, the axis of the movable platform 2041 and the axis of the pipe section where the movable platform 2041 is located cannot be completely ideal, and at this time, the axis of the movable platform 2041 and the axis of the pipe section where the movable platform 2041 is located are approximately coincident or approximately parallel, which is also included in the target posture of the present application.

[0229] Further, after the pipe profile data of the position where the internal welding machine is located is collected by using the sensor 4, the following operation can be performed: determining the pipe type of the position where the internal welding machine is located according to the pipe profile data; if the pipe type is a bent pipe, entering the step of calculating the target posture of the first section 201 according to the pipe profile data, so that the internal welding machine can adapt to the inner profile of the pipe in real time; if the pipe type is a straight pipe, controlling the extension distances of all the linear driving mechanisms 2042 to be the same, so that the internal welding machine can keep stable running.

[0230] Based on the above system, the internal welding machine with the posture adjusting system can also reduce the forward speed of the internal welding machine if the pipe type is a bent pipe after determining the pipe type of the position where the internal welding machine is located according to the pipe profile data, so that the running of the internal welding machine at the bent pipe is more stable, and the impact is reduced.

[0231] Please refer to Figure 20 , Figure 20 The posture adjusting device 204 provided in the embodiment is shown in the structural schematic view, which shows the fixed platform 2043 (connected to the second section 205 in the internal welding machine), the fixed end mounting seat 2045, the universal joint, the linear driving mechanism 2042, the movable end mounting seat 2044 and the movable platform 2041 (connected to the first section 201 in the internal welding machine). Figure 18 Figure 18 ​The first sub-section 201) in the figure; the central axis of the platform 2043 in the figure is the Z-axis direction, the horizontal direction perpendicular to the Z-axis is the X-axis direction, and the vertical direction perpendicular to the X-axis is the Y-axis direction, X, Y and Z represent the coordinate axes of a rectangular coordinate system, ΦX represents pitch, ΦY represents roll, and ΦZ represents yaw.

[0232] The above embodiments are supplemented by a specific attitude adjustment method, which comprises:

[0233] The pipeline profile data collected by the sensor 4;

[0234] The pipeline profile data collected by each sensor 4 is converted and spliced under the first sub-section 201 coordinate system by using the sensor installation correction coefficient obtained by pre-measurement;

[0235] The sensor installation correction coefficient is a homogeneous transformation matrix composed of the actual installation error measurement value of each sensor 4 and the installation design size of each structure. The profile data of each sensor 4 can be transformed to the first sub-section 201 coordinate system by multiplying the profile data scanned by each sensor 4 by the homogeneous transformation matrix. The specific process is as follows:

[0236] Suppose the pipeline profile data collected by one of the sensors 4 is A(x i , y i , 0), and the homogeneous transformation matrix is obtained according to the installation design size and the installation error: The Rot matrix is composed of the included angle between the coordinate axes of the sensor coordinate system and the first sub-section 201 coordinate system, and represents the rotation transformation; the p vector is composed of the coordinate values of the origin of the sensor coordinate system in the first sub-section 201 coordinate system, and represents the translation transformation.

[0237] The spliced pipeline profile data is represented as:

[0238]

[0239] Where P(x i , y i , z i ) represents the overall pipeline profile data, A, B, C... represent the pipeline profile data collected by each sensor 4, T A , T B , T C ... correspond to the homogeneous transformation matrix of each sensor 4, x i represents the X-axis coordinate of the i-th point on the pipeline profile data, y i represents the Y-axis coordinate of the i-th point on the pipeline profile data, and Z i represents the Z-axis coordinate of the i-th point on the pipeline profile data.

[0240] The process of solving the correction profile data by using the optimization objective function of the least square method to obtain the pipeline pose information of the current pipeline in the first segment 201 coordinate system is as follows:

[0241] The overall pipeline profile data is P(x i , y i , z i ) where i = 1, 2,..., n, n represents the number of points in the pipeline profile data, P0 represents a point (x0, y0, z0) on the pipeline axis, the point on the pipeline axis can also be represented as P0(x0, y0, z0), x0 represents the X-axis coordinate of the point on the pipeline axis, y0 represents the Y-axis coordinate of the point on the pipeline axis, and z0 represents the Z-axis coordinate of the point on the pipeline axis, V represents the axial vector of the pipeline, the axial vector of the pipeline can also be represented as V(a, b, c), a represents the coordinate of the axial vector V of the pipeline on the X-axis, b represents the coordinate of the axial vector V of the pipeline on the Y-axis, and c represents the coordinate of the axial vector V of the pipeline on the Z-axis, R i represents the distance from the profile point cloud data point P i (x i , y i , z i ) to the pipeline axis, and the mathematical description (i.e., the pipeline mathematical model) of the pipeline is represented as follows:

[0242] [c(y i -y0)-b(z i -z0)] 2 +[a(z i -z0)-c(x i -x0)] 2 +[b(x i -x0)-a(y i -y0)] 2 =R i 2

[0243] In this example, the following formula is used as the optimization objective function F(X), where R represents the pipeline radius:

[0244]

[0245] Solving the pipeline pose parameters: P0(x0, y0, z0), V(a, b, c), and R into solving the extreme value point X corresponding to the minimum value of F(X), where X = [P0, V, R].

[0246] Therefore, the nonlinear optimization problem is converted into the X corresponding to the minimum value of F(X), which is represented as follows:

[0247]

[0248] X represents P0(x0, y0, z0) in the parameters of the pipe mathematical model, V(a, b, c) represents the axial vector of the pipe, and R represents the radius of the pipe. That is, X = [x0; y0; z0; a; b; c; R].

[0249] For the extremum problem of the nonlinear function in this embodiment, the nonlinear function is linearized, the Jacobian matrix is constructed, singular value decomposition is performed, and the parameters in the nonlinear equation of the pipe mathematical model are solved by solving the linear equation set and iteration.

[0250] Specifically, the process of solving X is as follows:

[0251] Step 1: Set the initial value of the pipe pose parameter Among them: represents the coordinate estimation value of a point P0 on the pipe axis (in this embodiment, the pipe offset can be represented by the coordinates of a point on the pipe axis), represents the coordinate estimation value of a point P0 on the pipe axis (in this embodiment, the pipe offset can be represented by the coordinates of a point on the pipe axis), represents the coordinate estimation value of a point P0 on the pipe axis (in this embodiment, the pipe offset can be represented by the coordinates of a point on the pipe axis), represents the coordinate estimation value of a point P0 on the pipe axis (in this embodiment, the pipe offset can be represented by the coordinates of a point on the pipe axis), represents the estimation value of the pipe axial vector (in this embodiment, the pipe offset angle can be represented by the pipe axial vector), represents the coordinate estimation value of a point P0 on the pipe axis (in this embodiment, the pipe offset can be represented by the coordinates of a point on the pipe axis), represents the coordinate estimation value of a point P0 on the pipe axis (in this embodiment, the pipe offset can be represented by the coordinates of a point on the pipe axis), represents the coordinate estimation value of a point P0 on the pipe axis (in this embodiment, the pipe offset can be represented by the coordinates of a point on the pipe axis), represents the estimation value of the pipe radius.

[0252] Step 2: In order to reduce the operation amount of the derivative of F(X) in the optimization iteration process, a space rectangular coordinate system is established with as the origin and as the Z axis, and the pipe profile data P i (x i , y i , z i ) is converted to this coordinate system through the homogeneous transformation matrix U, so These constants are brought into F(X), the derivative of F(X) with respect to is taken, and the derivative function is set to 0 to obtain the following linear equation set:

[0253]

[0254] where Jac is the Jacobian matrix obtained by taking the partial derivative of f(X) with respect to its arguments:

[0255]

[0256] where the vector D expressing the fitting error is:

[0257]

[0258] Since is an overdetermined system of equations, the vector D is not in the column space of the Jac matrix, so the singular value decomposition method is used to solve ΔX. The iteration step ΔX is expressed as follows, the elements Δa, Δb, Δx, Δy and ΔR in ΔX are the coefficients of the projection vector of the vector D in the column space of Jac:

[0259]

[0260] Step 3: After solving the above linear equations to obtain the ΔX matrix, update the iteration parameters, and T is the symbol of the transpose matrix:

[0261]

[0262]

[0263]

[0264] Step 4: Determine whether the norm of ΔX is less than the required precision of iteration, if not, go to step 2 and continue iteration; if yes, stop iteration and output The X obtained by solving is the pipe pose information, which includes the attitude (i.e., the deflection angle relative to the first section 201) and the position (i.e., the offset relative to the first section 201) between the pipe and the first section 201. The attitude and position are sent to the multi-degree-of-freedom adjustment mechanism (such as a six-degree-of-freedom motion platform), so that the axis of the first section 201 and the axis of the pipe always coincide. At the same time, the walking mechanism makes the internal welding machine move forward along the pipe, so that the first section 201 can well adapt to the internal welding scene of walking motion in the curved pipe.

[0265] The posture adjusting device 204 (in the preferred embodiment, specifically a six-degree-of-freedom motion platform) can also, after obtaining the target pose, first perform workspace analysis on the target pose to determine whether the target pose is within the workspace of the posture adjusting device 204, and if not, give an execution target exception, and modify the target pose to the data closest to the original target pose within the executable workspace range. In combination with robot inverse kinematics, trajectory curve constraints generate the extension and retraction amounts of each electric cylinder of the six-degree-of-freedom motion platform, and the extension and retraction amounts of each electric cylinder are transmitted to the motor drivers of each electric cylinder through real-time network communication. The drivers drive the motor to rotate through a three-ring PID control. At the same time, each motor driver reports the current extension and retraction amounts of each axis to the communication master station, and reports the actual pose of the motion platform to the trajectory planning and generator through robot forward kinematics solution, so that the trajectory planning and generator can adjust the planned pose in a timely manner according to the actual pose, and improve the control accuracy of the multi-degree-of-freedom adjusting mechanism.

[0266] In the above preferred embodiment, the second section 205 is the inner welding machine body, and the fixed platform 2043 and the frame of the inner welding machine body are designed in an integrated structure, i.e., the fixed platform 2043 is part of the frame of the body, and the body moves accordingly, and the fixed platform 2043 also moves accordingly. The fixed platform 2043 is designed with mounting holes, the fixed end mounting seat 2045 is fixed on the fixed platform 2043 by bolts, the universal joint is fixed on the fixed end mounting seat 2045 by bolts, and the linear driving mechanism 2042 is connected with the universal joint by bolts.

[0267] Correspondingly, in this embodiment, the first section 201 is a taper head mechanism, and the movable platform 2041 and the frame of the inner welding machine taper head mechanism are designed in an integrated structure, i.e., the movable platform 2041 is part of the frame of the taper head mechanism, and the movable platform 2041 moves accordingly, and the taper head mechanism also moves accordingly. The movable platform 2041 is designed with mounting holes, the movable end mounting seat 2044 is fixed on the movable platform 2041 by bolts, and the linear driving mechanism 2042 is connected with the movable end mounting seat 2044 by bolts.

[0268] Through the above structure, when the pose of the movable platform 2041 relative to the fixed platform 2043 changes, the pose of the first section 201 relative to the second section 205 will also change, thereby ensuring that the inner welding machine can automatically turn when encountering a bent pipe under the control of the control system.

[0269] Please refer to Figure 22 , Figure 22 A structure diagram of an inner welding machine passing through a bent pipe is provided in the embodiments of the present application, which shows the second section 205, the posture adjusting device 204, the tensioning assembly 203, the first section 201, the sensor 4, the movable platform 2041, the linear driving mechanism 2042, the fixed platform 2043, and the pipe.

[0270] Each linear drive mechanism 2042 in the posture adjusting device 204 can realize a separate telescopic motion in space, and the control system can control the motion platform 2041 to complete a six-degree-of-freedom motion in space by controlling the telescopic amount of the linear drive mechanism 2042, so as to realize the change of the posture of the motion platform 2041 and achieve the purpose of the inner welding machine passing through a bend. The six degrees of freedom refer to the translational motion of the platform along the X, Y and Z coordinate axes, and the rotational motion (pitch φX, roll φY, yaw φZ, lateral X, longitudinal Z and vertical Y) around the three coordinate axes.

[0271] According to the motion state of the motion platform 2041, the response position and speed instruction signals of each linear drive mechanism 2042 are calculated, so as to control the motion of the motion platform 2041 and ensure that the motion is according to the predetermined trajectory; when the motion platform 2041 reaches the required position, the speed instruction signals of each linear drive mechanism 2042 are given as zero, and the motion platform 2041 stops moving to achieve the purpose of accurate point control. The inner welding machine moves forward and backward under the action of the walking mechanism, and when a bend is encountered, the distances that each linear drive mechanism 2042 needs to act are calculated according to the data input by the sensor 4, so that the motion platform 2041 moves to a suitable position to ensure that the inner welding machine does not collide with the inner wall of the pipe when passing through the bend. When the inner welding machine walks on a straight pipe section, the motion platform 2041 is parallel to the fixed platform 2043, the linear drive mechanisms 2042 of the motion platform 2041 have the same extension distance, and the initial posture is as shown in Figure 18 When the inner welding machine passes through a bend, the motion platform 2041 rotates relative to the fixed platform 2043, and the posture when passing through a lower bend is as shown in Figure 22 .

[0272] In order to improve the real-time performance, high speed and use efficiency of the control system, the controller analyzes the functions of each control module, and then combines the real-time requirements of each function in the control system to adopt the following overall design scheme of the platform control system:

[0273] Please refer to Figure 23 , Figure 23 for the overall design diagram of the control system provided by the embodiment of the application, which shows that the control system includes an upper computer management module (including an initialization module, a parameter setting, a communication module and a running parameter display), a communication interface, a multi-axis motion controller and a lower computer control module (including an electric mode, a test mode, an automatic mode, a servo drive module and an I / O module).

[0274] The real-time module in the embodiment, i.e., the platform control system, has a strong real-time requirement. Mainly includes: a position servo module, a servo drive module, a fault detection module. In the running process of the platform, the position servo module is the accurate position control of each axis, which is related to whether the actuator can successfully complete the corresponding motion trajectory; the servo drive module is the monitoring and control of the running state of each axis and the switching of the running state of each axis; the fault detection module detects the running state of each axis and the actuator, and when a fault occurs, the motion of the platform is immediately stopped to achieve the purpose of protecting personnel safety and the platform from damage.

[0275] The control system can also perform rationality analysis on the task according to the parameters input by the user, and has the function of shielding the control instruction of the super motion range. The control system has reasonable settings and monitoring on the motion parameter ranges such as the maximum speed and the maximum acceleration of the platform. If it is found that the input instruction of the user is unreasonable, the motion platform will be implemented according to the set reasonable maximum motion parameters, complete the continuous motion control, and also will alarm.

[0276] Since the examples in the method part correspond to the examples in the device part, the examples in the method part are described in the description of the examples in the device part, and will not be described here.

[0277] The application also provides a storage medium having a computer program stored thereon, which can implement the steps provided by the above-mentioned embodiments when executed. The storage medium can include: 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 media that can store program codes.

[0278] The application also provides an inner welding machine, which comprises a first section 201, a second section 205 and a posture adjusting system.

[0279] The posture adjusting system comprises a posture adjusting device 204, an electrical control module and a sensor 4.

[0280] The posture adjusting device 204 is arranged between the first section 201 and the second section 205; the posture adjusting device 204 comprises a movable platform 2041, a fixed platform 2043, a linear driving mechanism 2042 and a universal joint, the movable platform 2041 and the rack of the first section 201 are in an integral structure, the fixed platform 2043 and the rack of the second section 205 are in an integral structure, and the two ends of the linear driving mechanism 2042 are connected with the movable platform 2041 and the fixed platform 2043 through the universal joint respectively.

[0281] The sensor 4 is configured to collect pipeline profile data of a position of the internal welding machine.

[0282] The electrical control module is configured to calculate a target pose of the first sub-section 201 according to the pipeline profile data, and perform a motion inverse algorithm calculation on the target pose to generate a length change signal of the linear driving mechanism 2042; and the electrical control module is further configured to control the linear driving mechanism 2042 to perform extension and contraction movement by using the length change signal, so that the first sub-section 201 is in the target pose.

[0283] Internal welding machine alignment method

[0284] Figure 24 A flowchart of an internal welding machine alignment method provided by an embodiment of the present application.

[0285] The specific steps can include:

[0286] S101: detecting internal welding machine welding unit 304 circumferential pipeline profile data, and determining whether the pipeline end face is detected based on the pipeline profile data;

[0287] In the embodiment, the internal welding machine can be provided with a sensor 4 and a multi-degree-of-freedom adjusting mechanism 303. The internal welding machine can further include a cone head mechanism 301 and a machine body mechanism 302. Specifically, the sensor 4 can be arranged on the outer surface of the cone head mechanism 301, the multi-degree-of-freedom adjusting mechanism 303 can be arranged between the cone head mechanism 301 and the machine body mechanism 302, and the welding unit 304, the expansion shoe 305 and the expansion device 306 can be arranged on the cone head mechanism 301.

[0288] Referring to Figure 25 , Figure 25 A structural schematic diagram of an internal welding machine provided by an embodiment of the present application is shown in the figure, which shows the cone head mechanism 301, the sensor 4, the multi-degree-of-freedom adjusting mechanism 303, the welding unit 304, the expansion shoe 305, the expansion device 306 and the machine body mechanism 302. The machine body mechanism 302 includes a walking device 308, a brake device 309 and a flexible front wheel 3010.

[0289] In the embodiment, a plurality of sensors 4 can be arranged on the cone head mechanism 301, and each sensor 4 is configured to collect profile data of a corresponding pipeline wall surface around the welding unit 304 of the internal welding machine, including profile data of an inner wall of the pipeline and / or profile data of a pipeline end face groove.

[0290] In a preferred embodiment, the sensor 4 is a stripe laser displacement sensor, the laser stripe emitted by the sensor 4 irradiates on the pipe to form a laser profile line on the pipe, and the image of the laser profile line is collected and analyzed to determine whether the sensor 4 detects the end face of the pipe.

[0291] More specifically, the traveling device 308 on the body mechanism 302 drives the body mechanism 302 to move along the pipe towards the side where the taper head mechanism 301 is located, and the sensor 4 is located on the taper head mechanism 301 at the front side of the traveling direction relative to the tensioning device 306 and the welding unit 304, in other words, the sensor 4 is farther away from the body mechanism 302 relative to the tensioning device 306 and the welding unit 304, the emitting direction of the laser stripe of the sensor 4 is towards the side where the tensioning shoe 305 and the welding unit 304 are located, and the emitting direction of the laser stripe of the sensor 4 is inclined to the axial direction of the tensioning device 306 and towards the radial outer side of the tensioning device 306, and the length direction of the laser stripe of the sensor 4 is in the plane passing through the central axis of the tensioning device 306, further, the irradiation area of the laser stripe of the sensor 4 covers the radial outer side area opposite to the welding unit 304, so as to ensure that the pose of the taper head mechanism 301 can be detected and adjusted in real time to ensure that the welding unit 304 accurately faces the center of the weld between the two pipes.

[0292] The laser stripe emitted by the sensor 4 irradiates on the pipe to form a laser profile line, and the position and pose of the taper head mechanism 301 relative to the pipe are different, and the laser profile line formed by the laser stripe irradiating on the pipe is different in shape. Specifically, the deflection state of the central axis of the tensioning device 306 on the taper head mechanism 301 relative to the central axis of the pipe is different, and different shapes of laser profile lines are formed. For example, when the taper head mechanism 301 is in the straight pipe section of the pipe, when the central axis of the tensioning device 306 coincides with the central axis of the pipe, the laser profile line formed by the laser stripe emitted by the sensor 4 irradiating on the inner wall of the pipe is a straight line, and when the central axis of the tensioning device 306 has an angle of deviation with the central axis of the pipe, the length direction of the laser stripe emitted by the sensor 4 is inclined to the axial direction of the pipe, so that the laser profile line formed by the laser stripe emitted by the sensor 4 on the inner wall of the pipe is an arc, and the laser profile image collected by the sensor 4 in real time can be matched and compared with the preset bevel image, and then the bevel is recognized for alignment.

[0293] In a preferred embodiment of the method, the sensors 4 are preferably three, evenly distributed along the circumference. When the laser image of the sensor 4 changes to an L shape in the current sequential step, it is determined whether the sensor 4 detects the pipe bevel end face according to whether the detected laser profile image matches the preset profile image. Specifically, the profile data of each sensor 4 is converted into a binary profile image by equal proportion downsampling; the profile image is matched with the preset bevel profile image (such as a standardized bevel image); if the profile image matches the pre-stored bevel profile image (such as the similarity is greater than a preset value), it can be determined that the bevel is detected.

[0294] More specifically, the laser profile lines formed by the three sensors 4 are sent to the controller, the controller analyzes the images of the laser profile lines formed by the sensors 4 to obtain corresponding control parameters, and the multi-degree-of-freedom adjusting mechanism 303 acts according to the control parameters that are coaxial with the pipe, so that the cone head mechanism 301 is maintained in a state where the central axis of the tensioning device 306 coincides with the central axis of the pipe, i.e., the cone head mechanism 301 is maintained in the center of the pipe cross section, ensuring that the pipe internal welding machine smoothly travels along the inner wall of the pipe.

[0295] Meanwhile, the position of the cone head mechanism 301 relative to the pipe end will form laser profile lines of different shapes. Taking the pipe internal welding machine walking along the pipe while the cone head mechanism 301 of the pipe internal welding machine is maintained in a state where the central axis of the tensioning device 306 coincides with the central axis of the pipe as an example, when the cone head mechanism 301 is completely inside the straight pipe section or the tensioning device 306 and the welding unit 304 are also completely inside the straight pipe section, the laser stripes emitted by the sensors 4 only irradiate on the inner wall of the pipe, so that the laser profile line formed presents a straight line. When the pipe internal welding machine continues to travel to the bevel of the pipe end where the laser stripes emitted by the sensors 4 irradiate, the laser profile line formed is approximately L-shaped, and the shape of the laser profile line changes, so that the position of the cone head mechanism 301 of the pipe internal welding machine relative to the pipe end can be determined by analyzing and processing the image of the laser profile line. The laser profile image collected by the sensor 4 in real time can be matched and compared with the preset profile image (the preset profile image can be a standard laser profile line image formed when the laser stripes irradiate on the pipe end), so as to determine whether the sensor 4 scans and detects the pipe end, i.e., to know the position distance of the cone head mechanism 301 relative to the pipe end, and then the walking system can be automatically controlled to stop, and the multi-degree-of-freedom pose adjusting mechanism can be controlled to adjust the pose of the cone head so that the welding unit 304 in the cone head mechanism 301 of the internal welding machine is approximately stopped in the bevel region 3012.

[0296] S102: When the sensor 4 for detecting the profile data and the plane where the pipe end surface is located satisfy a preset distance, the internal welding machine driving mechanism is controlled to stop driving the internal welding machine along the pipe axis.

[0297] The target stop position is determined according to the pipe profile data, so that when the inner welding machine moves to the target stop position, the welding unit 304 in the taper head mechanism 301 moves into the bevel area 3012 (i.e. the area where the pipe bevel is located). After the target stop position is determined, the walking device 308 of the inner welding machine can be controlled to stop moving, so that the welding unit 304 and the expansion shoe 305 of the inner welding machine are substantially stopped near the pipe bevel.

[0298] In order to improve the accuracy and avoid the interference of the protrusions on the inner surface of the pipe on the detection image of the sensor, when the number of sensors 4 detecting the end face of the pipe is greater than 1, it is determined that the expansion shoe 305 of the inner welding machine is substantially in the bevel area 3012.

[0299] The inner welding machine is controlled to stop walking along the axial direction of the pipe by determining the distance relationship between the plane where the bevel is located and the sensors 4. When the profile image matches the pre-stored bevel profile image (e.g. the similarity is greater than a preset value), and the number of images matched by the sensors 4 is greater than 1, it can be determined that the bevel is detected by multiple sensors 4, avoiding the interference caused by the uneven inner wall of the pipe. At the same time, since the relative position between the sensor 4 and the expansion shoe 305 is known and unchanged, the relative position relationship between the expansion shoe 305 and the bevel can be substantially determined, and then the walking device 308 of the inner welding machine is controlled to stop, so that the welding unit 304 in the taper head mechanism 301 of the inner welding machine is substantially stopped in the bevel area 3012.

[0300] When the number of image matching sensors 4 is greater than 1, it can be determined that the multiple sensors 4 detect the groove, at this time the internal welding machine continues to walk a distance for the time difference of signal processing, inertia and / or system preset control flow in the pipe, in the process of detecting the pipe end face groove and determining that the sensor 4 detecting the pipe contour data and the plane where the pipe end face is located meet the preset distance, the system also processes the pipe contour data to obtain the position relationship of the pipe contour compared to the taper head mechanism 301, that is, in the image matching process, the approximate translation and rotation values of the groove shape in the contour image can also be determined, so that the welding unit 304 is made to be approximately coplanar with the plane where the groove is located by adjusting the multi-degree-of-freedom platform, and the central axis of the welding unit 304 is approximately coaxial with the central axis of the pipe on its side. If the welding unit 304 is located at the pipe groove at this time, the central axis of the welding unit 304 is approximately coaxial with the central axis of the groove. That is, the groove template image matched when starting the corner detection and the optimal fitting of the groove contour shape is basically located in the center of the contour image, and the position and pose of the taper head mechanism 301 are adjusted by outputting parameters to control the multi-degree-of-freedom attitude adjustment mechanism. In this way, the multi-degree-of-freedom platform can not only realize the alignment, but also adjust the position and pose of the internal welding machine relative to the pipe before alignment, when the axis of the internal welding machine is basically kept in the same line with the axis of the pipe where it is located, the walking system is automatically controlled to stop, so that the welding unit 304 in the taper head mechanism 301 of the internal welding machine is approximately stopped in the groove area 3012; for the possible deflection of the internal welding machine during walking or the offset caused by the internal welding machine passing the bend in the case of pipe bending, the attitude adjustment can make the alignment more accurate and fast.

[0301] When the position relationship between the sensor 4 and the plane where the pipe end face is located reaches the preset distance relationship, the alignment position is fine-adjusted by the multi-degree-of-freedom adjustment mechanism 303.

[0302] In other embodiments of the present application, whether the sensor 4 detecting the contour data and the plane where the pipe end face is located meet the preset distance can also be realized by a laser ranging sensor, an image sensor, a magnetic flux sensor and the like arranged on the internal welding machine. In other possible embodiments, the sensor 4 can be arranged on the taper head mechanism 301, the expansion shoe 305 of the expansion device 306, the welding unit 304 or near it, or on the body mechanism 302; when arranged on the expansion shoe 305, the welding unit 304 or near it, if the expansion shoe 305 and the welding unit 304 just protrude from the groove area 3012 of the pipe, the distance between them, the image, the light flux and the magnetic flux (when the pipe is a metal pipe) will change, and the corresponding signal change is detected by the sensor 4 to make the internal welding machine stop moving along the axial direction of the pipe, so that the sensor 4 and the plane where the pipe end face is located meet a certain distance.

[0303] Due to the large size and heavy weight of the internal welding machine, the alignment by only driving the internal welding machine through the walking device 308 cannot accurately achieve the alignment, and therefore, in the above embodiments, the internal welding machine can be first stopped in the pipe and the expansion shoe 305 is approximately located in the welding area, and then the alignment is finely adjusted through the following steps to achieve the automatic alignment.

[0304] S103: Calculate the positional relationship between the sensor 4 and the pipe end face, and adjust the multi-degree-of-freedom adjusting mechanism 303 between the cone head mechanism 301 and the machine body mechanism 302 through the pose information, so that the welding unit 304 on the cone head mechanism 301 is directly opposite the welding bevel, and the internal welding machine is relatively fixed with the pipe.

[0305] After the internal welding machine moves to the target stop position, the positional relationship between the sensor 4 and the pipe end face can be calculated from the pipe contour data. Specifically, the corner point detection can be performed on the obtained contour image; the coarse error coordinate values of the contour image vertices are obtained, and the contour data is fitted with a multi-joint polyline to obtain the accurate coordinates of the contour vertices; the accurate coordinates of the contour vertices are converted into the bevel feature space coordinates in the coordinate system of the cone head mechanism 301, and then the bevel pose information of the pipe bevel in the coordinate system of the cone head mechanism 301 is determined. The pose information includes the angle and offset data between the bevel and the cone head mechanism 301. According to the pose information, the multi-degree-of-freedom adjusting mechanism 303 between the cone head mechanism 301 and the machine body mechanism 302 is adjusted, and the welding torch in the welding unit 304 on the cone head mechanism 301 is directly opposite the bevel by adjusting the extension amount of one or more electric cylinders in the multi-degree-of-freedom adjusting mechanism 303. After the pose adjustment of the cone head mechanism 301 is completed, the expansion device 306 is extended to relatively fix the internal welding machine with the pipe.

[0306] The above-mentioned coordinate system of the cone head mechanism 301 is the coordinate system of the cone head mechanism 301, and the pipe bevel is the part to be welded in the pipe.

[0307] Since the scene using the internal welding machine is generally large in pipe diameter, and the welding area formed by the butt joint of the two pipes is relatively narrow, slight deviation of the internal welding machine during walking in the pipe can cause the pipe to be unable to accurately align.

[0308] After the bevel pose information is determined, the bevel pose information can be input to the multi-degree-of-freedom adjusting mechanism 303, and then the pose of the cone head mechanism 301 is adjusted by using the multi-degree-of-freedom adjusting mechanism 303, so that the welding torch of the welding unit 304 on the cone head mechanism 301 is directly opposite the weld center of the pipe bevel after the adjustment.

[0309] Further, the multi-degree-of-freedom adjusting mechanism 303 is a six-degree-of-freedom motion platform including multiple electric cylinders; correspondingly, the pose of the taper head mechanism 301 can be adjusted by: inputting the bevel pose information into the multi-degree-of-freedom adjusting mechanism 303, and changing the extension and retraction amounts of one or more electric cylinders according to the bevel pose information by using the multi-degree-of-freedom adjusting mechanism 303, so as to adjust the pose of the taper head mechanism 301.

[0310] When the pose adjustment is completed, the boots 305 are inflated to tighten the inner circumferential surface of the pipeline, so that the welding unit 304 is fixed relative to the inner circumferential surface of the pipeline.

[0311] Among them, after the welding torch of the welding unit 304 is aligned with the weld center of the pipeline bevel, the boots 305 located in the pipeline are inflated to tighten the inner wall of the pipeline, and after the other pipeline to be welded is butted from one side of the taper head mechanism 301, the boots 305 on the other side are inflated to tighten, and the alignment operation is completed. In other embodiments in the art, after the welding torch of the welding unit 304 is aligned with the weld center of the pipeline bevel, the other pipeline to be welded can be roughly aligned with the pipeline bevel first, and then the two groups of boots 305 are inflated to tighten the inner wall of the pipeline in sequence or simultaneously. At this time, the six-degree-of-freedom platform can also be used to adjust the interface width between the two pipelines to be welded to adapt to the welding requirements.

[0312] By the above-mentioned manner, the welding torch of the internal welding machine welding unit 304 can be automatically adjusted to a position aligned with the weld center of the pipeline bevel in the alignment scene, so that the internal welding machine realizes high-precision automatic alignment, and the welding quality is improved.

[0313] More specifically, the precise coordinates of each vertex of the contour can be determined by: constructing a bevel contour mathematical model corresponding to the contour data with the coordinates of the corner point as the initial value; and solving the contour mathematical model by using an optimization objective function of the least square method to obtain the precise coordinates of each vertex of the contour.

[0314] As for Figure 24In the corresponding other embodiments, the working scene of the internal welding machine can also be determined by the sensors 4. If the current working scene is a locating scene, the internal welding machine can further perform the following operations: performing splicing and coordinate system conversion on the pipe profile data collected by all the sensors 4 according to the sensor installation correction parameters, to obtain overall pipe profile data in the coordinate system of the taper head mechanism 301; determining pipe pose information of the current pipe in the coordinate system of the taper head mechanism 301 according to the overall pipe profile data; wherein the current pipe is the pipe corresponding to the pipe profile data; and adjusting the pose of the taper head mechanism 301 according to the pipe pose information by using the multi-degree-of-freedom adjusting mechanism 303, so that the axis of the taper head mechanism 301 coincides with the axis of the current pipe. The overall pipe profile data is the splicing result of the pipe profile data collected by each sensor 4, and is used to describe the overall profile shape of the inner wall of the pipe.

[0315] Specifically, if the internal welding machine is provided with M sensors 4, the current working scene of the internal welding machine can be determined in the following manner: collecting the pipe profile data by using the M sensors 4, and generating a binary profile image corresponding to the pipe profile data collected by each sensor 4; matching the binary profile image corresponding to each sensor 4 with a preset bevel profile image; if the number of successfully matched binary profile images is greater than or equal to N, it is determined that the current working scene of the internal welding machine is a butting scene; if the number of successfully matched binary profile images is less than N, it is determined that the current working scene of the internal welding machine is a locating scene, i.e., a working scene of walking along the pipe axis. Wherein, 0 < N ≤ M.

[0316] In the above process, the binary profile image is matched with the preset bevel profile image, and if the similarity of part or all of the binary profile image and the preset bevel profile image is greater than a preset similarity (such as 90%), it is determined that the binary profile image is successfully matched. In this embodiment, whether the current working scene is a butting scene or a locating scene is determined according to the number of successfully matched binary profile images. In order to improve the detection accuracy of the working scene, N can be equal to M, so as to avoid the interference caused by the local protrusions of the inner wall of the pipe. As a feasible implementation manner, M (such as M = 3) sensors 4 can be uniformly arranged on the taper head mechanism 301, so as to improve the comprehensiveness of collecting the pipe profile data.

[0317] The above-described processes are described in the following embodiments. Figures 26 to 29 The above-described processes are described in the following embodiments. Figure 26 A local enlarged view of the butting process between the welding unit 304 and the bevel provided by the embodiment of the present application; Figure 27 A schematic view of the bevel profile data collected by the sensor converted into a picture by downsampling provided by the embodiment of the present application;Figure 28 A schematic diagram of the result of the corner point detection of a groove profile provided by an embodiment of the present application is shown in the figure; Figure 29 A schematic diagram of the result of the groove profile fitting provided by an embodiment of the present application is shown in the figure.

[0318] Figure 26 The fixed steel pipe 3011, the groove area 3012, the welding unit 304, and the tensioning device 306 are shown in the figure. The multi-sensor acquisition system includes a stripe laser displacement sensor acquisition head, a sensor controller, and a network communication module. The alignment control processing flow includes corner point detection, groove profile optimal fitting, determination of a sensor correction coefficient, groove feature point splicing, groove pose calculation, cone head mechanism system adjustment control system, control of the working of the tensioning device of the front tensioning shoe 305, new pipe placement, and control of the working of the tensioning device of the rear tensioning shoe 305.

[0319] In the related art, there are two difficulties in the alignment of a bent pipe. (1) In the process of shaping the groove of the bent pipe, the groove cutting surface cannot be perpendicular to the pipe axis due to the inevitable installation error of the groove machine. (2) When aligning inside the bent pipe, the front wheel of the cone head mechanism cannot effectively fit the pipe wall, so that the cone head mechanism and the pipe axis form an included angle. At this time, the pose of the cone head mechanism of the internal welding machine needs to be adjusted following the pose of the groove, so that the welding torch in the welding unit 304 can be directly opposite the center of the weld. In view of the technical problems existing in the related art, the present application provides an automatic alignment device of an internal welding machine and an alignment method thereof, which is used to improve the ability of adjusting the pose of the cone head mechanism of the internal welding machine when the machine body moves forward and backward to find the alignment area during the alignment process. At the same time, the above scheme can take into account factors such as personnel safety, alignment quality, and equipment weight.

[0320] Specifically, the automatic alignment device of the internal welding machine and the alignment method thereof provided by the present application can be applied to the internal welding scene of the butt joint of the curved pipe. The alignment device can flexibly adjust the pose of the cone head mechanism 301, adaptively walk inside the bent pipe, and use the sensor detection system to provide feedback for the multi-degree-of-freedom adjustment mechanism 303 to achieve precise alignment. The present embodiment uses a precise sensor detection system to perform pipe profile data acquisition work for automatic alignment. The high-precision and high-flexibility six-degree-of-freedom motion platform enables the cone head mechanism 301 to adjust its position and pose within a certain range without constraints. The image matching algorithm with rotation scaling invariance can stably distinguish the positioning scene and the alignment scene. The corner point detection in the image space can obtain high-time-efficiency robust corner point position estimation. The profile fitting method based on the least square method can accurately obtain the feature point position of the actual groove. The product combining the multi-sensor acquisition system and the cone head mechanism pose adjustment system can be applied to the curved pipe alignment welding operation scene.

[0321] The automatic alignment device of the internal welding machine comprises a cone head mechanism 301, a sensor 4, a multi-degree-of-freedom adjusting mechanism 303, and a machine body mechanism 302. The cone head mechanism 301 comprises a plurality of welding units 304 and a tensioning device 306. The sensor 4 is installed on the rack of the cone head mechanism 301 and comprises a plurality of laser vision sensors (e.g., a stripe laser displacement sensor). The multi-degree-of-freedom adjusting mechanism 303 is connected between the cone head mechanism 301 and the machine body mechanism 302 and comprises a plurality of electric cylinders. The multi-degree-of-freedom adjusting mechanism 303 can make the cone head mechanism 301 deflect and offset relative to the machine body mechanism by controlling the lengths of the electric cylinders. The machine body mechanism 302 comprises a walking device 308, a brake device 309, and a flexible front wheel 3010, which can meet the requirements of the internal welding machine in terms of forward movement, backward movement, and stop movement in a curved pipeline.

[0322] The automatic alignment method of the internal welding machine comprises the following steps:

[0323] In step one, a plurality of laser vision sensors (e.g., three stripe laser displacement sensors) are used to detect the pipeline profile data around the internal welding machine tensioning shoe 305. The pipeline profile data collected by each laser vision sensor is converted into a binary profile image through downsampling, and the binary profile image is matched with a preset bevel profile image.

[0324] In order to improve the data scene discrimination rate, the pipeline profile data needs to be downsampled, and the image should be scaled in proportion to prevent image distortion. The sensor data is the coordinate value of the pipeline profile point, so the mapping relationship between the profile coordinate value and the pixel coordinate is established. The pixel where the coordinate value is located is assigned a value of 1, and the background pixel is assigned a value of 0, to obtain the binary profile image of the bevel profile.

[0325] The binary profile image and the preset bevel profile image exist in translation (Δx, Δy), rotation Δα, and scaling λ transformation. (Δx, Δy) represents the translation amount of the horizontal and vertical coordinates, Δα represents the rotation angle, and λ represents the scaling coefficient. The transformation relationship between the two is as follows:

[0326] m′[x, y] = t[λ(x cos Δα + y sin Δα) - Δx, λ(-x sin Δα + y cos Δα) - Δy];

[0327] wherein m[x, y] is the profile image, m′[x, y] is the part of the profile image corresponding to the template (preset bevel profile image), t[x, y] is the preset bevel profile image, x represents the horizontal coordinate, and y represents the vertical coordinate. Fourier transform is performed on both ends of the equation to obtain:

[0328] M′[u, v] = λ -2 e -2πj(uΔx+vΔy) T[λ-1 (u·cosΔα+v·sinΔα), λ -1 [(-u·sinΔα+v·cosΔα)];

[0329] M′[u, v] represents the result of the Fourier transform of m[x, y]; u and v represent the horizontal and vertical coordinates of the image coordinate system after the Fourier transform of the original image m′[x, y], i.e., the pixel position after the Fourier transform, so as to express the frequency and wavefront direction information of the original image; e represents the natural constant; j represents the imaginary number; T represents the result of the Fourier transform of the preset bevel contour image t.

[0330] Removing phase information from the above equation, it can be expressed in logarithmic polar coordinates as follows:

[0331] M[1gρ,α]=λ -2 T[1gρ-1gλ,α-Δα];

[0332] M[1gρ,α] represents removing phase information e -2πj(uΔx+vΔy) The result of the logarithmic-polar coordinate transformation is then performed. ρ represents the polar radius in the polar coordinate system. α represents the polar angle of the image M[1gρ, α] in the logarithmic-polar coordinate system. In this embodiment, α can be regarded as a reference about the image without rotation transformation, and α-Δα represents a rotation of Δα with respect to this image.

[0333] The rotation Δα and scaling λ are calculated using a phase correlation algorithm based on T[1gρ-1gλ, α-Δα]. The template image is then transformed according to the Δα and λ parameters, and the translation (Δx, Δy) is calculated by applying a phase correlation algorithm to the contour image. Based on the translation and rotation, the multi-degree-of-freedom attitude adjustment mechanism is adjusted so that when the bevel contour image is in the center of the entire image, the axis of the cone mechanism 301 always remains near the pipe axis, thus avoiding collision with the pipe wall during the pipe exit process of the cone mechanism 301.

[0334] This process can occur not only before the alignment method but also during the alignment method. That is, after determining whether the pipe end face has been detected and before controlling the inner welding machine drive mechanism to stop the inner welding machine from driving along the pipe axis, the translation and rotation obtained by the above method can be used as the gross translation and gross rotation values ​​of the pipe profile relative to the cone mechanism 301. This allows for attitude adjustment before the inner welding machine stops, making the alignment more accurate and faster.

[0335] According to the sensor installation correction parameter, the pipeline profile data collected by all the sensors is spliced and converted in the coordinate system to obtain overall pipeline profile data in the coordinate system of the taper head mechanism; the pipeline pose information of the current pipeline in the coordinate system of the taper head mechanism is determined according to the overall pipeline profile data; the pose of the taper head mechanism 301 is adjusted according to the pipeline pose information by using the pose adjusting mechanism of the taper head mechanism, so that the axis of the taper head mechanism 301 coincides with the axis of the current pipeline. The overall pipeline profile data is the splicing result of the pipeline profile data collected by each sensor 4, which is used to describe the overall profile shape of the inner wall of the pipeline. The sensor installation correction coefficient obtained by pre-measurement is used to splice and convert the pipeline profile data (i.e., overall pipeline profile point cloud data) collected by each sensor 4 in the coordinate system of the taper head mechanism;

[0336] The sensor installation correction coefficient is a homogeneous transformation matrix composed of the installation design size of each structure and the actual installation error measurement value of each sensor. By multiplying the profile data scanned by each sensor 4 by the homogeneous transformation matrix, the profile data of each sensor 4 can be transformed into the coordinate system of the taper head mechanism. The specific process is as follows:

[0337] Suppose the pipeline profile data collected by one of the sensors 4 is A(x i , y i , 0), and the homogeneous transformation matrix is obtained according to the installation design size and the installation error: where Rot represents the matrix of the rotation transformation, and the matrix is composed of the included angle of the corresponding coordinate axes of the sensor coordinate system and the taper head mechanism coordinate system; the p vector is composed of the coordinate values of the origin of the sensor coordinate system in the coordinate system of the taper head mechanism, and represents the translation transformation.

[0338] The spliced pipeline profile data is represented as:

[0339]

[0340] where P(x i , y i , z i ) represents the overall pipeline profile data, A, B, C... represent the pipeline profile data collected by each sensor 4, T A , T B , T C ... are the homogeneous transformation matrices of each sensor 4.

[0341] Step two: according to the matching result of the profile image, the stopping position of the walking device 308 of the inner welding machine is controlled, so that the welding unit 304 in the taper head mechanism 301 is stably stopped in the bevel region 3012. Figure 26The stop position of the welding unit 304 in the groove region 3012 is shown. When the image matching indicates that the pipe end face is detected, and the matching result is greater than 1, whether the positional relationship between the sensor 4 and the plane where the pipe end face is located reaches the preset distance relationship is calculated, and when it is satisfied, the internal welding machine is controlled to stop walking, so that the welding unit 304 stops in the groove region 3012.

[0342] Step three: based on the position of the stopped internal welding machine, the contour data at this time is obtained by each sensor 4, the contour image (i.e. the image corresponding to the pipe contour data) is obtained by binarization and downsampling, and the coarse error coordinates of each feature point in the contour image are obtained by corner detection.

[0343] Using the corner detection algorithm, the stable coarse error coordinates of each feature point of the contour can be obtained, and the corner detection result is as shown in Figure 25 .

[0344] Taking the coarse error coordinate value of the feature point in the contour image as the initial value, the contour data is optimally fitted to obtain the accurate coordinates of the groove contour feature point (i.e. the groove feature point);

[0345] Specifically, the process of fitting calculation based on the least square method of the pipe contour data taking the coordinates of the corner as the initial value to obtain the groove feature point is as follows:

[0346] Taking the coordinates of the corner as the initial value, the groove contour mathematical model corresponding to the pipe contour data is constructed, and the groove contour mathematical model y(x) can be expressed as:

[0347]

[0348] n represents the number of straight line segments;

[0349] a represents the intercept of y(x);

[0350] k j represents the slope difference of adjacent front and rear two line segments, j = 1, 2,..., n-1;

[0351] b j represents the horizontal coordinate of the position of the feature point, j = 1, 2,..., n-1;

[0352] ε(x-b j ) represents that if x ≥ b j , then ε(x-b j ) = 1, otherwise ε(x-b j ) = 0;

[0353] Through the obtained coarse error coordinates of each feature point of the contour image, it is converted into as an initial estimate value, and the symbol “^” is used to distinguish the initial value and the final value of the above letters.

[0354] The process of solving the contour mathematical model using the least squares method to obtain the bevel feature points is as follows:

[0355] The mathematical model y(x) of the bevel profile is a nonlinear function, and the optimization function F(x) is established as follows:

[0356]

[0357] The model parameters of y(x) are obtained by solving for the minimum value of the nonlinear function: a, b. j k j .

[0358] Plot the fitted result y(x) as Figure 29 As shown, the point where the slope of the function changes is taken as the feature point of the slope.

[0359] The coordinates of the precise feature points of the bevel profile in each sensor coordinate system are spliced ​​and transformed to the coordinate system of the cone mechanism to obtain the spatial coordinates of the bevel feature points. The homogeneous transformation matrix is ​​obtained by measuring the installation dimensions, and the coordinates of the bevel feature points in each sensor 4 are transformed to the coordinate system of the cone mechanism.

[0360] The position and orientation of the current pipe bevel circle in the cone mechanism coordinate system are calculated by using the spatial coordinates of the bevel feature points.

[0361] Let the bevel feature point be A. i (x i y i , z i When i = 3, three bevel feature points A1, A2, and A3 are extracted. The data parameters of the circle containing the bevel are obtained using the following formula:

[0362] 1. Normal vector of the bevel circle:

[0363] in

[0364] 2. Center coordinates:

[0365] in

[0366] In the above formula, the subscripts x, y, and z of R1 represent the coordinates of each coordinate axis.

[0367] 3. Circle radius R:

[0368] R = ||o-A1||.

[0369] According to the normal vector of the plane and the contour of the pipe groove (i.e., the deflection angle relative to the taper head mechanism 301) and the center coordinate (i.e., the deflection relative to the taper head mechanism 301), the welding torch of the welding unit 304 on the taper head mechanism 301 can be directed to the center of the groove weld by using the multi-degree-of-freedom adjusting mechanism 303 (i.e., a six-degree-of-freedom motion platform).

[0370] After the pose adjustment of the taper head mechanism 301 is completed, the expansion shoe 305 in the rear expansion mechanism on the taper head mechanism 301 is extended and tightly attached to the inner wall of the pipe; the new pipe to be aligned is installed, and the expansion shoe 305 in the front expansion mechanism on the taper head mechanism 301 is extended and tightly attached to the inner wall of the pipe, and the alignment is completed.

[0371] The embodiment can better suppress the interference of random errors introduced in the sensor measurement process by constructing a nonlinear optimization problem to solve the groove model parameters. At the same time, the use of the groove mathematical model can make the extraction accuracy of the groove feature points higher than the image resolution of the stripe laser displacement sensor, and provide strong guarantee for the alignment accuracy of the internal welding machine to be below 0.2 mm.

[0372] The alignment device provided in the embodiment is based on the cooperation of the sensor 4 and the multi-degree-of-freedom adjusting mechanism 303, realizes the groove pose detection and feedback to the multi-degree-of-freedom adjusting mechanism 303, and realizes the control of the position and attitude of the taper head mechanism 301 in the pipe by the multi-degree-of-freedom adjusting mechanism 303 through forward and inverse kinematics solving and controlling the extension and retraction amount of the electric cylinder, so as to achieve the effect of flexible alignment required by welding. The embodiment constructs a laser vision sensor measurement system to collect the spatial position information of the target object in the pipe alignment operation process of the internal welding machine; the pipe and groove pose calculation is completed through the image data processing unit; the calculated pose information is fed back to the multi-degree-of-freedom adjusting mechanism 303, and the spatial pose of the taper head mechanism 301 is adjusted in real time.

[0373] In the alignment method provided in the embodiment, the mathematical model of the groove is used to accurately describe the geometric shape of the pipe groove and the deflection angle and deflection existing between the taper head mechanism 301, and the numerical solution of the groove or part of the pipe contour geometric shape is iterated by the optimization method, so that the random errors of environmental interference factors and the manufacturing errors of the pipe and the groove can be better suppressed.

[0374] In the process of extracting the precise coordinates of the contour vertex, the traditional Douglas-Peucker polygon fitting uses the method of comparing the distance values of each contour point to obtain some special points, and taking the special points as the feature points of the polygon contour. However, in practical application, the following difficulties exist: on the one hand, due to the reflection characteristics of light, when measuring the intersection angle of two straight lines, the contour does not present a "sharp" triangular shape, so the actual groove contour angle point does not exist on the laser contour data; on the other hand, due to the influence of the visual obstruction of the laser sensor, the blurred edge of the steep contour, and the interference of stray light, the contour data always jumps. The least square fitting used in the embodiment can effectively suppress the contour data jump, and the least square fitting introduced in the contour fitting can accurately estimate the actual groove feature point which does not exist on the laser contour data. In the process of contour fitting, the initial iteration value of the feature point needs to be set, the contour data is converted to the image space by sampling the contour data in the X and Y directions at the same ratio, and the Hanis corner detection is used to obtain the coarse error estimation coordinates of the contour feature point. In this way, while reducing the data processing amount, the robust estimation value of the groove feature point coordinates can still be obtained. The estimation value is brought into the initial value of the groove contour fitting iteration, so that the iteration result can converge to the true value of the groove feature point coordinate. The embodiment extracts the groove vertex, calculates the position and attitude of the circular groove in the cone head mechanism coordinate system, and feeds back to the multi-degree-of-freedom adjusting mechanism 303 (six-degree-of-freedom motion platform) to adjust the attitude of the cone head mechanism in real time, which greatly increases the flexibility of the porting.

[0375] The inner welding machine aligning device provided by the embodiment of the application is used in an inner welding machine which comprises a sensor 4 arranged on a cone head mechanism 301 and a multi-degree-of-freedom adjusting mechanism 303 arranged between the cone head mechanism 301 and a body mechanism 302, and the inner welding machine aligning device comprises:

[0376] a boot 305 distributed circumferentially along the head of the inner welding machine,

[0377] a sensor 4 for detecting the contour data of the pipeline on the side of the welding unit 304 of the inner welding machine and judging whether the pipeline end face is detected based on the contour data;

[0378] a control system for controlling the driving mechanism of the inner welding machine to stop driving the inner welding machine along the axis of the pipeline when the sensor 4 for detecting the contour data and the plane where the pipeline end face is located satisfy a preset distance;

[0379] The control system is further used to calculate the position relationship between the sensor 4 and the pipeline end face to obtain pose information, and adjust the multi-degree-of-freedom adjusting mechanism 303 between the cone head mechanism 301 and the body of the inner welding machine through the pose information, so that the directly facing to-be-welded groove on the cone head mechanism 301 of the inner welding machine is obtained and the inner welding machine is relatively fixed with the pipeline.

[0380] Since the embodiments of the device part correspond to the embodiments of the method part, the embodiments of the device part are described with reference to the description of the embodiments of the method part, which will not be repeated here.

[0381] The application further provides a storage medium, which has a computer program stored thereon, and the computer program can implement the steps provided by the above embodiments when executed. The storage medium can include 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 media that can store program codes.

[0382] The application further provides an inner welding machine, which comprises a taper head mechanism 301, a body mechanism 302, a sensor 4, a multi-degree-of-freedom adjusting mechanism 303, a memory and a processor, the sensor 4 is arranged on the taper head mechanism 301, the multi-degree-of-freedom adjusting mechanism 303 is arranged between the taper head mechanism 301 and the body mechanism 302, the memory has a computer program stored therein, and the processor implements the steps provided by the above embodiments when calling the computer program in the memory.

[0383] The above embodiments are described in a progressive manner, and each embodiment mainly explains the difference from other embodiments, and the same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiments, since it corresponds to the method disclosed in the embodiments, the description is relatively simple, and the related parts can be referred to the description of the method part.

[0384] The above only is the preferred embodiment of the application, it should be pointed out that the above preferred embodiment should not be regarded as the limitation of the application, the protection scope of the application should be limited by the range defined by the claims. For ordinary skilled in the art, without departing from the spirit and scope of the application, can make several improvements and refinements, these improvements and refinements should also be regarded as the protection scope of the application.

Claims

1. A pipe welding machine characterized by, The utility model relates to a kind of pipe welding machines, including head (1), body (2) and first connecting mechanism (3); The head (1) is provided with tensioning mechanism (11) and welding mechanism (12); The body (2) is provided with walking system for walking in pipeline; The head (1) is connected with body (2) by first connecting mechanism (3), and the first connecting mechanism (3) has controllable activity freedom to enable the head (1) and body (2) to be relatively deflected; Further comprising sensor (4) for detecting pipeline arranged on the head (1), and the control system receives the data detected by the sensor (4) and analyzes and processes to obtain control parameters, and the first connecting mechanism (3) acts according to the control parameters to adjust the pose of the head (1), and the sensor (4) is circumferentially spaced apart on the head (1), and the central axis of the circumferential line where the sensor (4) is located coincides with the central axis of the tensioning mechanism (11), and the sensor (4) is a stripe laser displacement sensor to detect and collect pipeline profile data, and the control system analyzes and processes the form of laser profile line formed when the laser stripe emitted by the sensor (4) is irradiated on the pipeline to obtain control parameters; Based on sensor installation correction coefficient, the profile data scanned by each sensor (4) is transformed into corrected profile data in the head (1) coordinate system; Based on the corrected profile data, the position and attitude of the current pipeline in the head (1) coordinate system are calculated out; The pipeline mathematical model is solved to obtain the pipeline pose information of the current pipeline in the head (1) coordinate system; The attitude and position between the pipeline and the head (1) are obtained, and adjustment signal is generated.

2. The pipe welder of claim 1, wherein, The first connecting mechanism (3) includes static end (31) and dynamic end (32), the static end (31) is connected with the body (2), the dynamic end (32) is connected with the head (1), and a plurality of activity components (33) are arranged in parallel between the static end (31) and the dynamic end (32) to enable the static end and the dynamic end to be relatively movable.

3. The pipe welder of claim 2, wherein, The activity component (33) is a linear telescopic component, one end of the linear telescopic component is movably connected with the static end (31), and the other end is movably connected with the dynamic end (32).

4. The pipe welder of claim 1, wherein, The first connecting mechanism (3) is a parallel kinematic mechanism or a serial kinematic mechanism, and has two degrees of freedom to six degrees of freedom.

5. The pipe welder of claim 1, wherein, The emission direction of the laser stripe of the sensor (4) is towards the side where the tensioning mechanism (11) and the welding mechanism (12) are located, the emission direction of the laser stripe of the sensor (4) is inclined to the axial direction of the tensioning mechanism (11) and towards the radial outer side of the tensioning mechanism (11), the length direction of the laser stripe of the sensor (4) is in the plane passing through the central axis of the tensioning mechanism (11), and the laser stripe irradiation area of the sensor (4) covers the radial outer side area opposite to the welding mechanism (12).

6. The pipe welder of claim 1, wherein, The control system comprises a coaxial unit for analyzing and processing data detected by the sensor (4) to obtain a coaxial control parameter, and the first connecting mechanism (3) acts according to the coaxial control parameter to make the central axis of the welding mechanism (12) on the head (1) coincide with the central axis of the pipeline at the position of the welding mechanism (12).

7. The pipe welder of claim 1, wherein, The control system comprises a butting unit for analyzing and processing data detected by the sensor (4) to obtain a butting control parameter, and the first connecting mechanism (3) acts according to the butting control parameter to make the welding mechanism (12) face the center of the weld between the two pipelines to be butt-jointed.

8. The pipe welder of claim 7, wherein, The butting unit comprises: A scene judgment module for analyzing and processing data detected by the sensor (4) to determine whether the scene is a butting scene in which the sensor (4) detects the end of the pipeline; the sensor (4) is provided with M sensors, the M sensors are used to collect pipeline profile data, and a binary profile image corresponding to the pipeline profile data collected by each sensor (4) is generated; each binary profile image corresponding to the sensor (4) is matched with a preset bevel profile image; if the number of matched binary profile images is greater than or equal to N, it is determined that the current working scene of the pipeline internal welding machine is a butting scene; if the number of matched binary profile images is less than N, it is determined that the current working scene of the pipeline internal welding machine is a locating scene in which the pipeline internal welding machine walks along the pipeline axis, wherein 0 A measurement module for analyzing and processing data detected by the sensor (4) to obtain the distance from the sensor (4) to the plane of the end of the pipeline when the scene is a butting scene; A parking module for issuing an instruction to control the walking system to park the body (2) when the distance from the sensor (4) to the plane of the end of the pipeline reaches a walking stop condition; A butting fine adjustment module for analyzing and processing data detected by the sensor (4) in the parked state of the body (2) to obtain a fine adjustment control parameter, wherein the profile data at this time is obtained by each sensor (4), the profile image is obtained by binaryzation and downsampling, the coarse error coordinates of each feature point in the profile image are obtained by corner point detection, the accurate coordinates of the bevel profile feature points are obtained by fitting the profile data with the coarse error coordinates of the feature points in the profile image as initial values, the accurate coordinates of the bevel profile feature points in the coordinate system of each sensor are spliced and converted to the coordinate system of the head (1) to obtain the spatial coordinates of the bevel feature points, the homogeneous transformation matrix is obtained by measuring the installation size, the spatial coordinates of the bevel feature points in each sensor (4) are converted to the coordinate system of the head (1), the position and attitude of the circle of the current pipeline bevel in the coordinate system of the head (1) are calculated according to the spatial coordinates of the bevel feature points, and the first connecting mechanism (3) acts according to the fine adjustment control parameter to make the welding mechanism (12) face the center of the weld between the two pipelines to be butt-jointed.

9. The pipe welder of claim 1, wherein, The walking system comprises a traveling mechanism (51), the traveling mechanism (51) comprises a plurality of walking wheel assemblies (511) arranged along the circumference of the body (2) at intervals, and the walking wheel assemblies (511) are connected to a tensioning mechanism (512) arranged on the body (2).

10. The pipe welder of claim 9, wherein, The walking wheel assemblies (511) are arranged on both sides of the body (2) in the diameter direction, and the tensioning mechanism (512) is a tensioning hydraulic cylinder connected between the two walking wheel assemblies (511).

11. The pipe welder of claim 9, wherein, Each walking wheel assembly (511) is provided with a walking motor (513), and the walking wheel assemblies (511) are controlled by electronic differential when turning.

12. The pipe welder of claim 1, wherein, The walking system comprises a brake mechanism (52), the brake mechanism (52) comprises a brake cylinder (521), a brake pad (522), and a retaining elastic element (523), the brake pad (522) is driven by the brake cylinder (521) to move between a braking position and a releasing position, and the brake pad (522) is further connected with the retaining elastic element (523) for driving the brake pad (522) to be retained in the braking position.

13. The pipe welder of claim 1, wherein, The walking system comprises a flexible wheel assembly (53), the flexible wheel assembly (53) comprises a wheel (531), a wheel seat (532), and an elastic assembly (533), the wheel (531) is arranged on the wheel seat (532), the wheel seat (532) is hinged to the body (2), the rotation plane of the wheel seat (532) is along the radial direction of the body (2), and the elastic assembly (533) is connected between the wheel seat (532) and the body (2).

14. The pipe welder of claim 13, wherein, The flexible wheel assembly (53) further comprises an angle adjusting motor (534) arranged on the wheel seat (532) and connected with the wheel (531), and the angle adjusting motor (534) is used for adjusting the traveling direction of the wheel (531).

15. The pipe welder of claim 1, wherein, A battery unit (6) is further provided, and the battery unit (6) is used for supplying power to the tensioning mechanism (11), the welding mechanism (12), the walking system, and the first connecting mechanism (3).

16. The pipe welder of claim 1, wherein, The body (2) is divided into a plurality of segments along the pipeline axis direction, adjacent segments are connected through a second connecting mechanism (10), and the second connecting mechanism (10) is a deflectable connecting mechanism.

17. The pipe welder of claim 16, wherein, The second connecting mechanism (10) comprises a first end (101), a second end (102), a universal joint (103), and a flexible connecting element (104), the universal joint (103) and the flexible connecting element (104) are connected between the first end (101) and the second end (102), the flexible connecting element (104) is distributed in the circumference of the universal joint (103), the first end (101) is connected with a previous segment, and the second end (102) is connected with a next segment.

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