Prefabricated pipe joint welding system and method for offshore platform jacket

Abstract

The invention belongs to the field of welding systems, and particularly discloses an offshore platform jacket prefabricated pipe joint welding system and method.The offshore platform jacket prefabricated pipe joint welding system comprises a rack body, a positioning and mounting mechanism, a welding mechanism and a control module used for controlling the welding system to work; the rack body moves in the X-axis direction through the first guide rail. The positioning and mounting mechanism comprises a displacement rack and a rotary driving assembly, the displacement rack is arranged below the rack main body, a to-be-welded prefabricated pipe is detachably connected to the displacement rack, and the rotary driving assembly is arranged on the displacement rack and used for driving the to-be-welded prefabricated pipe to rotate with the axis of the to-be-welded prefabricated pipe as a rotating shaft; the welding mechanism comprises a welding robot and a welding gun, the welding robot is movably arranged on the machine frame body, the welding gun is fixedly connected to the tail end of the welding robot, and a linear driving assembly used for driving the welding robot to move in the Y-axis direction and the Z-axis direction is arranged on the machine frame body. By means of the method, the welding efficiency of the prefabricated pipe joints to be welded can be improved, and the welding precision is higher.

Description

Technical Field

[0001] This application belongs to the field of welding systems, and more specifically, relates to a welding system and method for prefabricated pipe joints of jacket framework for offshore platforms. Background Technology

[0002] Offshore platforms are large, complex, and technologically advanced engineering projects widely used in offshore oil and gas development, playing a vital role in the exploration and development of offshore oil and gas resources. The jacket structure is a key component of an offshore platform, and its quality directly affects the overall quality of the platform. In a jacket-type platform, the jacket is a framework constructed by welding intersecting steel pipes, containing numerous pipe joints (such as…). Figure 1 Since jacket platforms need to withstand extreme environmental loads such as storms and waves during service, it is necessary to ensure the welding quality and strength of the pipe joints.

[0003] Currently, the main pipe joints of offshore engineering jackets are T, K, Y, and their combinations. These joints are intersecting lines and require prefabrication and welding in a workshop. Because the intersecting line welds have complex spatial trajectories and the welding production cycle is generally long, it is difficult to guarantee the stability of weld quality. Currently, the welding of jacket pipe joints mostly relies on manual welding by experienced welders with professional qualifications. However, due to the harsh working environment, manual welding is labor-intensive and inefficient. Some methods for welding jacket pipe joints use clamps to clamp and fix the jacket, followed by welding robots. However, because the TKY pipe joint welds are complex spatial curve welds formed by pipe intersections, the welding path points and welding postures are complex, making it difficult for welding robots to precisely weld each weld. This results in certain errors during welding, affecting the welding quality of the pipe joints. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this application provides a welding system and method for prefabricated pipe nodes of offshore platform jackets, aiming to solve the problems of low welding efficiency and easy welding errors in current jacket pipe node welding.

[0005] This application provides a welding system for prefabricated pipe nodes of a jacket structure on an offshore platform, specifically including a frame body, a positioning and installation mechanism, a welding mechanism, and a control module for controlling the operation of the welding system; the frame body moves along the X-axis direction via a first guide rail; the positioning and installation mechanism includes a positioner frame and a rotary drive assembly, the positioner frame being disposed below the frame body, the prefabricated pipe to be welded being detachably connected to the positioner frame with its axis along the X-axis direction, and the rotary drive assembly being disposed on the positioner frame to drive the prefabricated pipe to be welded to rotate with its axis as the rotation axis; The welding mechanism includes a welding robot and a welding torch. The welding robot is movably mounted on the main frame, and the welding torch is fixedly connected to the end of the robotic arm of the welding robot. The main frame is equipped with a linear drive assembly for driving the welding robot to move along the Y and Z axes. The system also includes a vision positioning unit for acquiring the actual weld position and bevel size, and an arc tracking unit for correcting the welding path during the welding process. Both the vision positioning unit and the arc tracking unit are mounted on the welding robot and are electrically connected to the control module.

[0006] Compared with the prior art, the technical solution conceived in this application, by installing the prefabricated pipe to be welded on the positioner frame and driving the prefabricated pipe to be welded to rotate through the rotation drive assembly, adjusts the position of the pipe node, so that the robot can easily weld the pipe node at different positions. Moreover, the frame body can move along the X-axis direction, and the welding robot can move along the Y-axis and Z-axis directions on the frame body. The welding robot has a larger range of motion, which can improve the welding efficiency of the welding robot controlling the welding torch. At the same time, the welding accuracy can be improved through the vision positioning unit and the arc tracking unit.

[0007] As a further preferred embodiment, the linear drive assembly includes a Y-axis electric moving stage and a Z-axis electric moving stage. The Y-axis electric moving stage is fixedly mounted on the frame body, and the Z-axis electric moving stage is fixedly connected to the output end of the Y-axis electric moving stage. The welding robot is fixedly connected to the output end of the Z-axis electric moving stage.

[0008] By adopting the above technical solution, the Y-axis electric moving stage and the Z-axis electric moving stage work together to enable the welding robot to move in the Y-axis and Z-axis directions, so that the welding robot can better perform welding operations.

[0009] As a further preferred embodiment, the positioning frame includes a first mounting base and a second mounting base arranged coaxially. The second mounting base moves along the X-axis direction via a second guide rail to move closer to or further away from the first mounting base, and the precast tube to be welded is positioned between the first mounting base and the second mounting base.

[0010] By adopting the above technical solution, the precast pipe to be welded is hoisted between the first mounting base and the second mounting base, and the second mounting base is driven to approach the first mounting base, which can clamp and fix the precast pipe to be welded for welding purposes, making the installation convenient and quick.

[0011] As a further preferred embodiment, the rotary drive assembly includes a first rotary drive motor and two first turntables. The two first turntables are rotatably connected to the first mounting base and the second mounting base respectively and are arranged opposite to each other. The two first turntables are both located on the same axis with the axis as their rotation axis. The first rotary drive motor is fixedly connected to the first mounting base or the second mounting base. The first turntables are coaxially fixedly connected to the output shaft of the first rotary drive motor. At least three first limiting grippers are equidistantly arranged around the periphery of the first turntables.

[0012] By adopting the above technical solution, the precast pipe to be welded is located between two first turntables during installation. The position of the precast pipe to be welded is fixed by the first limiting gripper. The first rotary drive motor drives the turntable to rotate, which can drive the precast pipe to be welded to rotate, thereby realizing the rotation of the precast pipe to be welded, so as to realize the welding of different pipe nodes on the precast pipe to be welded.

[0013] As a further preferred embodiment, the positioning frame includes a fixed base, a rotating frame, and a rotating drive component. The rotating frame is rotatably connected to the fixed base, and the rotation axis of the rotating frame is set along the Y-axis direction. The precast tube to be welded is detachably connected to the rotating frame. The rotating drive component is set on the rotating frame and the rotating drive component is set on the fixed base for driving the rotating frame to rotate.

[0014] By adopting the above technical solution, after the precast pipe to be welded is installed on the rotating frame, the rotation of the rotating frame can drive the precast pipe to be welded to rotate, and adjust the angle of the pipe node of the precast pipe to be welded, making it easier for the welding robot to operate during welding, avoiding interference from the branch pipe, and improving the welding quality.

[0015] As a further preferred embodiment, the rotating frame includes a connecting plate, a first positioning plate, a second positioning plate, and a linear drive component. The connecting plate is rotatably connected to the fixed base. The first and second positioning plates are both disposed on the side of the connecting plate away from the fixed base and are located on the same axis. The linear drive component is fixedly connected to the connecting plate to drive the first and second positioning plates to move closer or further away. The second positioning plate slides towards the side closer to the first positioning plate to fix the prefabricated pipe to be welded.

[0016] By adopting the above technical solution, the precast pipe to be welded is hoisted between the first positioning plate and the second positioning plate. The linear drive drives the second positioning plate to slide closer to the first positioning plate to fix the precast pipe to be welded, thus realizing the installation of the precast pipe to be welded. The installation is convenient and quick.

[0017] As a further preferred embodiment, the rotary drive assembly includes a second rotary drive motor and two second turntables. The two second turntables are rotatably connected to the first positioning plate and the second positioning plate, respectively, and are arranged opposite to each other. The two second turntables are both located on the same axis with the axis as their rotation axis. The second rotary drive motor is fixedly connected to the first positioning plate or the second positioning plate. The second turntables are coaxially fixedly connected to the output shaft of the second rotary drive motor. At least three second limiting grippers are equidistantly arranged around the periphery of the second turntables.

[0018] By adopting the above technical solution, the precast pipe to be welded is installed between two second turntables. The position of the precast pipe to be welded is fixed by the second limiting gripper. The second rotary drive motor drives the turntable to rotate, which can drive the precast pipe to be welded to rotate, so as to realize the rotation of the precast pipe to be welded and to realize the welding of different pipe nodes on the precast pipe to be welded.

[0019] As a further preferred embodiment, the welding torch includes a single-wire welding torch and a double-wire welding torch that can be automatically switched.

[0020] By adopting the above technical solution, according to welding requirements

[0021] This application discloses a welding method for prefabricated pipe nodes of jacket foundations for offshore platforms, which is implemented using the aforementioned welding system and includes the following steps:

[0022] S1: Install the precast pipe to be welded onto the positioner frame;

[0023] S2: Start the control module, retrieve the welding template program for the prefabricated pipe to be welded, and start it;

[0024] S3: Welding system operation:

[0025] S301: Based on the actual assembly position of the workpiece, a vision positioning unit or contact sensor is used to correct the intersection line laser vision scanning path point.

[0026] S302: The welding robot moves along the repaired laser vision scanning path points, while the vision positioning unit collects the weld point cloud of each path point of the intersection line according to the scanning path.

[0027] S303: Based on the collected weld points, the actual coordinates of the first welding path point and the actual bevel size of each intersection line path point are obtained through cloud computing.

[0028] S304: Replace the coordinates of the first weld path point in the welding template program with the actual coordinates described in step S303;

[0029] S305: Calculate the difference between the actual groove size described in step S303 and the theoretical groove size of the weld segment in the welding template for each weld segment of the intersection line. If the difference exceeds the limit, proceed to step S306; otherwise, proceed to step S309.

[0030] S306: Calculate the average actual bevel size of each path point described in step S303 within the weld segment, and calculate the width of a single weld pass under the average bevel size within the weld segment.

[0031] S307: Predict the welding process parameters corresponding to the weld width mentioned in S306, and refresh the process parameters in the welding template program;

[0032] S308: Based on the coordinates of the welding path points of the first weld bead and the width of the single weld bead obtained in steps S304-S307, obtain the offset and coordinates of the welding path points of the intersection lines of each layer, and refresh the welding template program.

[0033] S309: Preheat the workpiece to a specified temperature;

[0034] S310: Welding is performed according to the new welding template program, and the arc tracking unit is used to correct the welding path during the welding process;

[0035] S4: Determine whether all pipe node intersection welding has been completed; if completed, stop welding and finish the welding operation; if not completed, start welding the next pipe node intersection and proceed to step S3.

[0036] As a further preferred embodiment, in step S303, the bevel dimensions include the bevel angle, the bevel width, and the bevel height.

[0037] In summary, compared with the prior art, the technical solutions conceived in this application have the following main technical advantages:

[0038] 1. In this application, the precast pipe to be welded is installed on a positioner frame. The precast pipe to be welded is driven to rotate by a rotary drive assembly, and the position of the pipe node is adjusted so that the robot can easily weld the pipe node at different positions. The frame body can move along the X-axis, and the welding robot can move along the Y-axis and Z-axis on the frame body. The welding robot has a larger range of motion, which can improve the welding efficiency of the welding robot controlling the welding torch. At the same time, the welding accuracy can be improved by using a vision positioning unit and an arc tracking unit.

[0039] 2. After the precast pipe to be welded is installed on the rotating frame, the rotation of the rotating frame can drive the precast pipe to be welded to rotate, and adjust the angle of the pipe node of the precast pipe to be welded, so that the welding robot can operate easily during welding, ensure that the welding is in a near-ship welding posture, reduce the difficulty of welding process development, and improve welding quality.

[0040] 3. This application uses a visual positioning unit to detect the actual weld position and bevel size during the welding process. Based on the detection results, the welding trajectory, welding posture, and welding process parameters in the welding template program are corrected. This method avoids the problem of the program failing to execute due to large deviations between the actual weld and the theory. It also solves the problem that it is difficult to accurately plan the welding trajectory for complex spatial curve welds with intersection lines by only using weld positioning, thus ensuring the feasibility of automated welding of TKY pipe joint intersection lines. Attached Figure Description

[0041] Figure 1 This is a schematic diagram of the overall structure of the precast pipe to be welded;

[0042] Figure 2 This is a schematic diagram of the overall structure provided in Embodiment 1 of this application;

[0043] Figure 3 This is a schematic diagram of the overall structure provided in Embodiment 2 of this application;

[0044] Figure 4 This is a schematic diagram of the overall structure provided in Embodiment 3 of this application;

[0045] Figure 5 This is a schematic diagram of the intersection line and the path points of the intersection line;

[0046] Figure 6 This is a schematic diagram of the pipe joint bevel, where t b -Branch wall thickness, t D Supervisor wall thickness, t W - Bevel height, W - width of root pass weld, Ψ - dihedral angle (in the figure, the dihedral angle is equal to the angle between the main pipe and the branch pipe), Φ - bevel angle.

[0047] In all the accompanying drawings, the same reference numerals are used to denote the same elements or structures, wherein:

[0048] 1. Main frame; 11. Linear drive assembly; 111. Y-axis electric moving stage; 112. Z-axis electric moving stage; 2. Positioning and mounting mechanism; 21. Positioning frame; 211. First mounting base; 212. Second mounting base; 213. Fixed base; 214. Rotating frame; 2141. Connecting plate; 2142. First positioning plate; 2143. Second positioning plate; 2144. Linear drive component; 215. Rotary drive component; 22. Rotary drive assembly; 221. First rotary drive motor; 222. First turntable; 223. First limiting gripper; 224. Second rotary drive motor; 225. Second turntable; 226. Second limiting gripper; 3. Welding mechanism; 31. Welding robot; 32. Welding torch; 4. First guide rail; 5. Second guide rail; 6. Preheating device. Detailed Implementation

[0049] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0050] Example 1:

[0051] Reference Figure 2 This application discloses a welding system for prefabricated pipe nodes of offshore platform jackets, used for welding such as... Figure 1 The welding of the prefabricated pipe joints includes a frame body 1, a positioning and installation mechanism 2, a welding mechanism 3, and a control module for controlling the operation of the welding system. After the prefabricated pipe is installed on the positioning and installation mechanism 2, the welding mechanism 3 is started through the control module to perform the welding operation. The frame body 1 is a gantry frame, with both ends of the frame body 1 mounted on the ground. Two parallel first guide rails 4, both arranged along the X-axis, are fixedly connected to the ground. The bottom ends of both ends of the frame body 1 are fixedly connected to the first guide rails 4, allowing the frame body 1 to move along the X-axis via the first guide rails 4.

[0052] The positioning and installation mechanism 2 includes a positioner frame 21 and a rotary drive assembly 22. The positioner frame 21 is located below the frame body 1. The precast pipe to be welded is detachably connected to the positioner frame 21 and its axis is set along the X-axis. The rotary drive assembly 22 is set on the positioner frame 21 to drive the precast pipe to be welded to rotate with its axis as the rotation axis. By driving the precast pipe to be welded to rotate through the rotary drive assembly 22, the position of the pipe node is adjusted, so that the robot can easily weld the pipe nodes at different positions.

[0053] Welding mechanism 3 includes a welding robot 31 and a welding torch 32. The welding robot 31 is movably mounted on the frame body 1, and the welding torch 32 is fixedly connected to the end of the robotic arm of the welding robot 31. The frame body 1 is equipped with a linear drive assembly 11 for driving the welding robot 31 to move along the Y and Z axes. The Y axis is a direction perpendicular to the X axis on the horizontal plane, and the Z axis is a vertical direction. The welding robot 31 can move along the X axis with the frame body 1, and can also move in the Y and Z axes through the linear drive assembly 11, so as to facilitate welding. Human 31 controls welding torch 32 to perform welding operations. In this embodiment, welding robot 31 is a commonly used robot in the field, which can be a robotic arm or other control equipment. The welding torch 32 includes a single-wire welding torch 32 and a double-wire welding torch 32 that can be automatically switched. In addition, the welding mechanism 3 also includes a welding power source, a water cooler, a wire feeder, a shielding gas device, and an automatic torch changing device for switching between the single-wire welding torch 32 and the double-wire welding torch 32. The welding power source and welding torch 32 are preferably of the form of gas metal inert gas (MIG) welding. The automatic torch changing device is fixedly installed on the frame body 1.

[0054] In this embodiment, the linear drive assembly 11 includes a Y-axis electric moving stage 111 and a Z-axis electric moving stage 112. The Y-axis electric moving stage 111 is fixedly installed on the top of the frame body 1, and the Z-axis electric moving stage 112 is fixedly connected to the output end of the Y-axis electric moving stage 111. The welding robot 31 is fixedly connected to the output end of the Z-axis electric moving stage 112. The welding robot 31 can move in the Y and Z axis directions through the Y-axis electric moving stage 111 and the Z-axis electric moving stage 112. The frame body 1 drives the welding robot 31 to move in the X-axis direction, and the prefabricated pipe to be welded is arranged along the X-axis direction when it is installed, so that the welding robot 31 controls the welding torch 32 to weld the pipe node of the prefabricated pipe to be welded.

[0055] To improve welding accuracy, the system also includes a vision positioning unit for acquiring the actual weld position and bevel size, and an arc tracking unit for correcting welding path deviation during the welding process. Both the vision positioning unit and the arc tracking unit are fixedly connected to the welding robot 31 and are electrically connected to the control module. Specifically, the vision positioning unit includes a laser vision camera and point cloud processing software. The laser vision camera enables the welding robot 31 to accurately acquire the actual weld position, and the point cloud processing software is used to calculate the weld position and bevel size. The arc tracking unit determines the welding path deviation by monitoring the changes in welding current or welding voltage in real time and controls the swing amplitude of the welding torch 32 to compensate for it.

[0056] To facilitate the installation of the precast pipe to be welded, in this embodiment, the positioning frame 21 includes a first mounting base 211 and a second mounting base 212 coaxially arranged along the X-axis. The first mounting base 211 is fixedly installed on the ground, and a second guide rail 5 arranged along the X-axis is fixedly connected to the ground. The second mounting base 212 moves along the X-axis to approach or move away from the first mounting base 211 via the second guide rail 5. The precast pipe to be welded is placed between the first mounting base 211 and the second mounting base 212. The precast pipe to be welded is hoisted between the first mounting base 211 and the second mounting base 212, and the second mounting base 212 is driven to approach the first mounting base 211. This allows for clamping and fixing of precast pipes of different lengths to facilitate welding. The positioning frame 21 has a load-bearing capacity of 10-60 tons, which meets the requirements for welding the intersection line of pipe nodes in large guide frames.

[0057] To drive the precast tube to rotate around its axis, the rotary drive assembly 22 in this embodiment includes a first rotary drive motor 221 and two first turntables 222. The two first turntables 222 are rotatably connected to the first mounting base 211 and the second mounting base 212 respectively and are arranged opposite to each other. Both first turntables 222 rotate around their axes and are located on the same axis. The first rotary drive motor 221 is fixedly connected to the first mounting base 211 or the second mounting base 212. The first turntables 222 are coaxially fixedly connected to the output shaft of the first rotary drive motor 221. At least three first limiting grippers 223 are fixedly connected at equal intervals around the periphery of the first turntables 222. When the precast tube to be welded is installed, it is located between the two first turntables 222. The position of the precast tube to be welded is fixed by the first limiting grippers 223. The first rotary drive motor 221 drives the turntables to rotate, which can drive the precast tube to be welded to rotate, thereby facilitating the welding of different tube nodes on the precast tube to be welded.

[0058] Example 2:

[0059] Reference Figure 3 The difference between this embodiment and embodiment 1 is that a preheating device 6 is also provided on the frame body 1. The preheating device 6 includes a vertical shaft, a preheating robot, a flame gun and a flame preheater. The vertical shaft is set on the frame body 1, the preheating robot is connected to the output end of the vertical shaft and moves up and down, the flame gun is fixed at the end of the preheating robot's robotic arm, and the flame preheater provides energy to the flame gun.

[0060] Example 3:

[0061] Reference Figure 4 The difference between this embodiment and embodiments 1 and 2 is that the positioner frame 21 includes a fixed base 213, a rotating frame 214, and a rotating drive component 215. The rotating frame 214 is rotatably connected to the fixed base 213, and the rotation axis of the rotating frame 214 is set along the Y-axis. The precast tube to be welded is detachably connected to the rotating frame 214. The rotating drive component 215 is set on the fixed base 213 to drive the rotating frame 214 to rotate, so that the precast tube to be welded can be flipped. The rotating drive assembly 22 is set on the rotating frame 214 to enable the precast tube to be welded to rotate around the axis. With this structure, different tube nodes on the precast tube to be welded can be welded, and the angle of the same tube node can be adjusted during welding, which is convenient for the welding robot 31 to control the welding gun 32 to weld, thereby improving the welding effect.

[0062] To facilitate the installation of the precast pipe to be welded, the rotating frame 214 includes a connecting plate 2141, a first positioning plate 2142, a second positioning plate 2143, and a linear drive component 2144. The connecting plate 2141 is rotatably connected to the fixed base 213, and the rotation axis is set along the Y-axis. The first positioning plate 2142 and the second positioning plate 2143 are both slidably connected to the side of the connecting plate 2141 away from the fixed base 213 and are located on the same axis. The linear drive component 2144 includes two hydraulic cylinders, which are respectively fixedly connected to... The first positioning plate 2142 and the second positioning plate 2143 are driven to move closer or further away from each other at both ends of the connecting plate 2141. The second positioning plate 2143 slides towards the side closer to the first positioning plate 2142 to fix the prefabricated pipe to be welded. The prefabricated pipe to be welded is hoisted between the first positioning plate 2142 and the second positioning plate 2143. The linear drive 2144 drives the second positioning plate 2143 to slide towards the side closer to the first positioning plate 2142 to clamp and fix the prefabricated pipe to be welded, thereby realizing the installation of the prefabricated pipe to be welded.

[0063] To drive the precast tube to be welded to rotate, the rotary drive assembly 22 includes a second rotary drive motor 224 and two second turntables 225. The two second turntables 225 are rotatably connected to the first positioning plate 2142 and the second positioning plate 2143, respectively, and are arranged opposite to each other. The two second turntables 225 are both located on the same axis with their axis as the rotation axis. The second rotary drive motor 224 is fixedly connected to the first positioning plate 2142 or the second positioning plate 2143. The second turntables 225 are coaxially fixedly connected to the output shaft of the second rotary drive motor 224. At least three second limiting claws 226 are fixedly connected at equal intervals around the periphery of the second turntables 225. When the precast tube to be welded is installed, it is located between the two second turntables 225. The position of the precast tube to be welded is fixed by the second limiting claws 226. The second rotary drive motor 224 drives the turntables to rotate, which can drive the precast tube to be welded to rotate, so as to realize the rotation of the precast tube to be welded and to realize the welding of different tube nodes on the precast tube to be welded.

[0064] This application also discloses a welding method for prefabricated pipe nodes of offshore platform jackets, which is implemented using the above-mentioned welding system and includes the following steps:

[0065] S1: Install the prefabricated pipe to be welded on the positioner frame; the prefabricated pipe to be welded must be a qualified pipe joint workpiece, and a qualified pipe joint workpiece is one that has completed the root pass welding and weld surface cleaning, and meets the following requirements: the angle between the main pipe and the branch pipe is between 29° and 90°; the bevel error of the weld along the entire intersection line is ≤5% of the branch pipe wall thickness; there are no protrusions on the bevel processing surface; the root pass welding quality meets the requirements.

[0066] S2: The operator inputs the pipe node workpiece number into the integrated control software interface, starts the control module, retrieves the welding template program for the prefabricated pipe to be welded, and starts the process after confirming that everything is correct. The welding template program is a welding program for standard pipe node workpieces established by technicians using robot offline programming software before the welding system runs. Standard pipe node workpieces refer to pipe nodes where the pipe dimensions, assembly accuracy, and bevel dimensions are all standard values. The pre-established welding template program can achieve automatic welding of standard pipe node workpieces, ensuring that the welding quality meets the requirements. Figure 6 As shown, the bevel dimensions include the bevel angle, bevel width, and bevel height.

[0067] S3: Welding system operation:

[0068] S301: Call the laser vision scanning program. Based on the actual assembly position of the workpiece, use the laser vision camera or contact sensor in the vision positioning unit to correct the coordinates of the welding start point of the intersection line in the laser vision scanning program, thereby correcting the laser vision scanning path points of the entire intersection line; for example... Figure 5 As shown, the intersection path points are set as discrete points with equal spacing on the intersection line. The welding robot can form a smooth intersection trajectory by moving according to these discrete path points.

[0069] S302: The welding robot moves along the repaired laser vision scanning path, while the laser vision camera in the vision positioning unit collects weld point clouds at each path point of the intersection line according to the scanning path.

[0070] S303: Point cloud processing software is used to obtain the actual coordinates and actual bevel size of the first welding path point of each intersection line path point based on the collected weld point cloud computing. When the current weld bevel width is less than 20mm, a single wire welding gun is used. In the welding of pipe joints of multiple branch pipes, a single wire welding gun is used for adjacent positions of two branch pipes that cannot be reached by a double wire welding gun. For other positions that can be reached by a double wire welding gun, a double wire welding gun is selected first.

[0071] S304: Replace the coordinates of the first weld path point in the welding template program with the actual coordinates described in step S303.

[0072] S305: Calculate the difference between the actual bevel size in step S303 and the theoretical bevel size in the welding template for each weld segment of the intersection line. Different positions of the weld segment correspond to theoretical bevel sizes. If the difference exceeds the limit, proceed to step S306; otherwise, proceed to S309. The weld segment is preferably divided into segments according to the bevel cross-sectional area change rate and welding angle. The multi-layer, multi-pass welding arrangement method and welding process are the same within the same weld segment.

[0073] S306: Calculate the average actual bevel size of each path point in step S303 within the weld segment, and use the automatic weld bead planning program to calculate the width of a single weld bead under the average bevel size within the weld segment.

[0074] S307: Enable the welding process parameter prediction model to predict the welding process parameters corresponding to the weld width of S306 and refresh the process parameters in the welding template program.

[0075] S308: Based on the coordinates of the welding path points of the first weld bead and the width of a single weld bead obtained in steps S304-S307, obtain the offset and coordinates of the welding path points of the intersection lines of each layer, and refresh the welding template program.

[0076] S309: After the welding template program is refreshed, the workpiece is preheated to the specified temperature; the preferred method for preheating the workpiece is flame or resistance heating.

[0077] S310: Welding is performed according to the new welding template program. During the welding process, the arc tracking unit is used to correct the welding path and ensure welding quality.

[0078] S4: Determine whether all pipe node intersection welding has been completed; if completed, stop welding and finish the welding operation; if not completed, start welding the next pipe node intersection and proceed to step S3.

[0079] It should be understood that expressions such as "comprising" and "may include" as used in this application indicate the existence of the disclosed functions, operations, or constituent elements, and do not limit one or more additional functions, operations, and constituent elements. In this application, terms such as "comprising" and / or "having" may be interpreted as indicating a specific characteristic, number, operation, constituent element, component, or combination thereof, but should not be interpreted as excluding the existence or possibility of adding one or more other characteristics, numbers, operations, constituent elements, components, or combinations thereof.

[0080] It should be understood that the terms “center,” “upper,” “lower,” “front,” “rear,” “left,” “right,” “vertical,” “horizontal,” “inner,” “outer,” “clockwise,” “counterclockwise,” “axial,” “radial,” and “circumferential” indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0081] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0082] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0083] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. An offshore platform jacket pre-fabricated pipe node welding system, characterized by, The system comprises a rack body (1), a positioning and mounting mechanism (2), a welding mechanism (3) and a control module for controlling the welding system to work. The rack body (1) is moved along the X-axis direction through a first guide rail (4). The positioning and mounting mechanism (2) comprises a variable-position rack (21) and a rotary driving assembly (22), the variable-position rack (21) is arranged below the rack body (1), a prefabricated pipe to be welded is detachably connected to the variable-position rack (21) and the axis of the prefabricated pipe to be welded is arranged along the X-axis direction, the rotary driving assembly (22) is arranged on the variable-position rack (21) and is used for driving the prefabricated pipe to be welded to rotate around the axis as the rotary shaft. The welding mechanism (3) comprises a welding robot (31) and a welding torch (32), the welding robot (31) is movably arranged on the rack body (1), the welding torch (32) is fixedly connected to the end of the mechanical arm of the welding robot (31), and a linear driving assembly (11) for driving the welding robot (31) to move along the Y and Z-axis directions is arranged on the rack body (1). The system further comprises a visual positioning unit for acquiring the actual welding seam position and the groove size and an arc tracking unit for correcting the welding path during the welding process, the visual positioning unit and the arc tracking unit are arranged on the welding robot (31), and the visual positioning unit and the arc tracking unit are electrically connected with the control module.

2. An offshore platform jacket pre-fabricated pipe joint welding system as claimed in claim 1, wherein, The linear driving assembly (11) comprises a Y-axis electric moving table (111) and a Z-axis electric moving table (112), the Y-axis electric moving table (111) is fixedly mounted on the rack body (1), the Z-axis electric moving table (112) is fixedly connected to the output end of the Y-axis electric moving table (111), and the welding robot (31) is fixedly connected to the output end of the Z-axis electric moving table (112).

3. An offshore platform jacket pre-fabricated pipe joint welding system as defined in claim 1 wherein, The variable-position rack (21) comprises coaxially arranged first and second mounting seats (211) and (212), the second mounting seat (212) is moved along the X-axis direction through a second guide rail (5) to approach or move away from the first mounting seat (211), and the prefabricated pipe to be welded is arranged between the first and second mounting seats (211) and (212).

4. An offshore platform jacket pre-fabricated pipe joint welding system as claimed in claim 3, wherein, The rotary driving assembly (22) comprises a first rotary driving motor (221) and two first rotary tables (222), the two first rotary tables (222) are rotationally connected to the first and second mounting seats (211) and (212) and are oppositely arranged, the two first rotary tables (222) are both rotary around the axis as the rotary shaft and are located on the same axis, the first rotary driving motor (221) is fixedly connected to the first or second mounting seat (211) or (212), the first rotary table (222) is coaxially fixedly connected to the output shaft of the first rotary driving motor (221), and at least three first limiting clamps (223) are equidistantly arranged on the circumferential side of the first rotary table (222).

5. An offshore platform jacket pre-fabricated pipe node welding system as defined in claim 1, wherein, The variable position frame (21) comprises a fixed seat (213), a rotating frame (214) and a rotating driving member (215), the rotating frame (214) is rotationally connected to the fixed seat (213), the rotating shaft of the rotating frame (214) is arranged along the Y-axis direction, the prefabricated pipe to be welded is detachably connected to the rotating frame (214), the rotating driving assembly (22) is arranged on the rotating frame (214), and the rotating driving member (215) is arranged on the fixed seat (213) and used for driving the rotating frame (214) to rotate.

6. An offshore platform jacket pre-fabricated pipe node welding system as claimed in claim 5, wherein, The rotating frame (214) comprises a connecting plate (2141), a first positioning plate (2142), a second positioning plate (2143) and a linear driving member (2144), the connecting plate (2141) is rotationally connected to the fixed seat (213), the first positioning plate (2142) and the second positioning plate (2143) are arranged on the side, away from the fixed seat (213), of the connecting plate (2141) and are located on the same axis, the linear driving member (2144) is fixedly connected to the connecting plate (2141) and is used for driving the first positioning plate (2142) and the second positioning plate (2143) to move close to or away from each other, and the second positioning plate (2143) slides towards the side close to the first positioning plate (2142) to fix the prefabricated pipe to be welded.

7. An offshore platform jacket pre-fabricated pipe node welding system as claimed in claim 6, wherein, The rotating driving assembly (22) comprises a second rotating driving motor (224) and two second rotating discs (225), the two second rotating discs (225) are rotationally connected to the first positioning plate (2142) and the second positioning plate (2143) respectively and are oppositely arranged, the two second rotating discs (225) are rotationally arranged around the same axis, the second rotating driving motor (224) is fixedly connected to the first positioning plate (2142) or the second positioning plate (2143), the second rotating disc (225) is coaxially fixedly connected to the output shaft of the second rotating driving motor (224), and at least three second limiting clamping jaws (226) are equidistantly arranged on the circumferential side of the second rotating disc (225).

8. A system for welding pre-fabricated tubular joints for an offshore platform jacket according to any one of claims 7, wherein, The welding gun (32) comprises a single-wire welding gun (32) and a double-wire welding gun (32) capable of automatic switching.

9. A method of welding a pre-fabricated tubular joint for an offshore platform jacket, characterised in that, The welding system is realized by adopting any one of the welding systems in claims 1-8, and comprises the following steps: S1: installing the prefabricated pipe to be welded on the variable position frame (21); S2: starting the control module, calling the welding template program of the prefabricated pipe to be welded and starting; S3: the welding system runs: S301: according to the actual assembly position of the workpiece, using the visual positioning unit or the contact sensing to correct the laser visual scanning path points of the intersecting line; S302: the welding robot (31) moves according to the corrected laser visual scanning path points, and the visual positioning unit collects the weld point cloud of each path point of the intersecting line according to the scanning path; S303: calculating the actual coordinate of the first welding path point of each intersecting line path point and the actual groove size according to the collected weld point cloud; S304: replacing the coordinate of the first welding path point in the welding template program with the actual coordinate in step S303. S305: Calculate the difference between the actual groove size of each weld segment of the intersecting line and the theoretical groove size of the weld segment in the welding template, and if the difference exceeds the limit, run step S306, otherwise run S309; S306: Calculate the average value of the actual groove size of each path point in the weld segment in step S303, and calculate the single-pass weld width under the average groove size in the weld segment; S307: Predict the welding process parameters corresponding to the weld width in S306, and refresh the process parameters in the welding template program; S308: Obtain the offset and coordinates of each layer of intersecting line welding path points according to the first-pass welding path point coordinates and single-pass weld width obtained in steps S304-S307, and refresh the welding template program; S309: Preheat the workpiece to a specified temperature; S310: Weld according to the new welding template program, and enable the arc tracking unit to correct the welding path during the welding process; S4: Determine whether all pipe node intersecting line welding is completed; if completed, stop welding and complete the welding operation; if not completed, start the next pipe node intersecting line welding and go to step S3.

10. A method of welding a pre-fabricated tubular joint for an offshore platform jacket according to claim 9, wherein, In step S303, the groove size includes the groove angle, the groove width and the groove height.

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