Multi-layer multi-channel intelligent welding equipment and welding method based on double-sided double arcs

Abstract

The invention provides multi-layer and multi-pass intelligent welding equipment based on double-face double arcs and a welding method, and relates to the technical field of multi-layer and multi-pass welding. The welding equipment comprises a stand column, a cross beam, two mechanical arms, a first visual detector, two second visual detectors, two moving seats, a base, a ground rail, a workbench and a rotary driver, the ground rail is arranged beside the workbench, the stand column is fixed to the base, one end of the cross beam is arranged at the top of the stand column, and the other end of the cross beam is arranged on the base. The rotary driver is used for driving the cross beam to rotate in the horizontal plane, the two moving seats are arranged on the two long edges of the cross beam correspondingly, each mechanical arm is arranged on the corresponding moving seat, and a welding gun is arranged at the tail end of each mechanical arm. Each second visual detector is arranged at the tail end of the corresponding mechanical arm, the first visual detector is arranged at the position of the cross beam, and the movable base is used for moving along the cross beam in a reciprocating mode.

Description

Technical Field

[0001] This invention relates to the field of multi-layer, multi-pass welding technology, and more specifically, to a multi-layer, multi-pass intelligent welding device and welding method based on double-sided, double-arc welding. Background Technology

[0002] There are numerous applications of welding medium and heavy plate components in shipbuilding and steel structure, such as columns and beams in typical steel structures, the bottom, sides, and longitudinal and transverse bulkheads of ships, and the segmented connection of various parts of the ship.

[0003] For these thicker plates, K-type or X-type bevels are required to reduce the amount of welding work, with K-type bevels being more commonly used. However, due to cumulative errors and inaccurate on-site inspections, the weld quality is poor. In addition, the complexity of the bevel structure makes the corresponding welding process complicated, resulting in low welding efficiency. Summary of the Invention

[0004] To address the aforementioned problems, this invention provides a multi-layer, multi-pass intelligent welding device based on a double-sided, double-arc design, comprising: a column, a crossbeam, two robotic arms, a first vision detector, two second vision detectors, two movable seats, a base, a ground rail, a worktable, and a rotary actuator. The ground rail is positioned beside the worktable, and the base is used for reciprocating movement along the ground rail. The column is fixed to the base, and one end of the crossbeam is positioned on the top of the column. The rotary actuator is positioned on the top of the column and is used to drive the crossbeam to rotate in a horizontal plane. The two movable seats are respectively positioned at the two long sides of the crossbeam. Each robotic arm is positioned at one of the movable seats, and each robotic arm has a welding torch at its end. Each second vision detector is positioned at the end of one robotic arm, and the first vision detector is positioned at the crossbeam. The movable seats are used for reciprocating movement along the crossbeam, and the second vision detectors are used to detect the area in front of the corresponding welding torch. The first vision detectors are used to detect the workpiece on the worktable.

[0005] Optionally, the rotary drive includes a servo motor, a bearing, a large gear, and a small gear. The servo motor is located at the top of the column, the bearing is located at the rotatable connection between the column and the crossbeam, the large gear is located at one end of the crossbeam, the small gear meshes with the large gear, the small gear is connected to the output shaft of the servo motor, and the bearing is a deep groove ball bearing.

[0006] The worktables are an even number and arranged in pairs on the left and right sides of the ground rail, with multiple pairs of worktables arranged along the extension direction of the ground rail.

[0007] The welding workstation consists of the column, beam, two robotic arms, a first vision detector, two second vision detectors, two moving seats, a base, a worktable, and a rotary drive. Multiple welding workstations are arranged sequentially on the ground rail.

[0008] Optionally, the column is a shell structure with an internal cavity. A side thread hole is provided on the side wall of the column, communicating with the cavity inside the column. A first top thread hole is provided at the top of one end of the crossbeam, communicating with the cavity of the column. A second top thread hole is provided at the top of the movable base, communicating with the bottom surface of the movable base. A wire spool is provided at the base for storing welding wire.

[0009] The welding wire extends from the wire spool and is inserted into the side wire hole. It then passes through the cavity and extends from the top of the crossbeam through the first top wire hole. It is then fed into the two second top wire holes, passes through the moving seat, and is fed along the robotic arm into the corresponding welding gun. A bracket is provided at the top of one end of the crossbeam, and the welding wire is suspended from the top of the bracket. Nylon sleeves are fitted on the side walls of the first top wire hole, the second top wire hole, and the side wire hole. The nylon sleeves are used to cover the welding wire.

[0010] Optionally, the welding equipment further includes two inductive switches, two fixed limit blocks, a rotation limit block, and a rotation controller. The output shaft of the servo motor is equipped with a torque sensor, which is used to detect the torque of the servo motor's output shaft.

[0011] Two fixed limiting blocks are respectively disposed on the left and right sides of the top of the column. Each inductive switch is disposed in front of one of the fixed limiting blocks and spaced apart from it. The rotating limiting block is disposed at one end of the crossbeam and is disposed on the axis of the crossbeam.

[0012] The rotation limiting block is used to rotate with the crossbeam between the two fixed limiting blocks.

[0013] When the rotation limit block passes the inductive switch, the inductive switch is triggered and sends a signal.

[0014] The two inductive switches, the torque sensor, and the servo motor are respectively connected to the rotation controller;

[0015] The rotation controller is used to control the rotation of the servo motor, and to control the servo motor to decelerate based on the signal emitted by the inductive switch. When the torque detected by the torque sensor is greater than the set value, the controller controls the servo motor to continue to rotate and output at low power.

[0016] Optionally, the first visual detector includes a plurality of first line scan detectors and a plurality of second line scan detectors.

[0017] The first line scan detector includes a first boom, a first line scan laser, and a first camera. The first boom is suspended from the bottom surface of the crossbeam, the first line scan laser is located at the front end of the first boom, and the first camera is located at the rear end of the first boom.

[0018] The second line scan detector includes a second boom, a second line scan laser, and a second camera. The second boom is suspended at the bottom surface of the crossbeam, the second line scan laser is located at the rear end of the second boom, and the second camera is located at the front end of the second boom. Multiple first and second line scan detectors are arranged alternately along the long side of the crossbeam.

[0019] When the crossbeam is positioned above the worktable, multiple first line-scanning lasers irradiate the front of the crossbeam with first line lasers. These first line lasers are arranged parallel or collinearly. Multiple first cameras are used to capture images of the front of the crossbeam. The images captured by the first cameras contain the first line lasers, and the image acquisition areas of the multiple first cameras extend along the long front side of the crossbeam.

[0020] Multiple second-line scanning lasers irradiate the rear of the crossbeam with second-line lasers. These lasers are arranged parallel or collinearly. Multiple second cameras capture images of the rear of the crossbeam, and these images contain the second-line laser light. The image acquisition areas of the multiple second cameras extend along the long rear side of the crossbeam.

[0021] Each of the first booms and each of the second booms intersects the crossbeam at the same first predetermined angle in the horizontal plane.

[0022] Optionally, the first line laser emitted by any two adjacent first line-scan lasers may be of different colors, and each first camera lens may be provided with a first filter, which is used to receive only the first line laser emitted by the first line-scan lasers located at the same first boom.

[0023] The second line laser emitted by any two adjacent second line scan lasers is of different colors. Each second camera lens is provided with a second filter, which is used to receive only the second line laser emitted by the second line scan laser at the same second boom.

[0024] Optionally, the top of the column is a cylindrical structure, and the top sidewall of the column has multiple threaded holes. These threaded holes are evenly spaced along the circumference of the cylinder, and the inductive switch is located in front of these threaded holes.

[0025] One end of the fixed limiting block is connected to a handle, and the other end is connected to a bolt. The bolt is used for threaded connection to any one of the plurality of threaded holes, one of which is a reference hole. When the bolt is connected to the reference hole, and the rotating limiting block is blocked by the fixed limiting block, the crossbeam is in a reference position. The crossbeam in the reference position is perpendicular to the direction of movement of the base.

[0026] When the bolt is connected to other threads, and the rotation limit block is blocked by the fixed limit block, the position of the crossbeam is tilted at different angles in the horizontal plane relative to the reference position, so that the visual detection direction of the multiple first line scan detectors and the multiple second line scan detectors in the horizontal plane is tilted at different angles relative to the moving direction of the base, and the corresponding different angles are calculated by the servo motor.

[0027] In addition, the present invention also provides a welding method using the aforementioned welding equipment, the welding method comprising:

[0028] The crossbeam is rotated to a position parallel to the ground rail by a rotary drive, and the workpiece is hoisted onto the worktable. The workpiece is equipped with multiple vertical stiffeners.

[0029] The crossbeam is rotated to a position perpendicular to the ground rail by the rotary driver, and moved by the base, so that the first vision detector can obtain the three-dimensional point cloud of the workpiece.

[0030] Visual detection of bevel information: Based on the three-dimensional point cloud, the base, the two moving seats and the robotic arm move in coordination to enable the two second visual detectors to obtain the K-shaped bevel size information at the vertical stiffener.

[0031] Arrangement of weld layers: Based on the K-groove size information, calculate and arrange the weld layers on both sides of the vertical stiffener.

[0032] Multi-layer, multi-pass welding: Based on the layer arrangement of the weld seams on both sides of the vertical stiffener, two welding torches are used to perform multi-layer, multi-pass welding on the weld seams on both sides of the vertical stiffener.

[0033] The step of visually inspecting the bevel information for each of the multiple vertical stiffeners and then performing the multi-layer, multi-pass welding is performed.

[0034] Optionally, based on the K-type groove size information, calculating and arranging the weld passes on both sides of the vertical stiffener includes:

[0035] Based on the K-type bevel size information, bevel data for the bevel angle, bevel depth, and bevel root gap of each V-type bevel of the K-type bevel are calculated.

[0036] Determine the weld leg size based on the bevel data or manual settings;

[0037] Based on the bevel root gap and the weld leg size, the thickness and number of the first weld bead are determined, and the thickness of each subsequent weld bead is equal to the weld leg size.

[0038] Using the formula for the number of layers:

[0039] Ai = Ji / p + 1;

[0040] Calculate the number of weld beads in each layer after the first layer, where Ai is the number of weld beads in the i-th layer, i≥2, Ji is the root gap of the i-th layer, p is the weld leg size, and Ji / p is an integer.

[0041] Set the root of the bevel as the zero point of the coordinate system, and use the horizontal coordinate formula for the weld bead: Xi = (i-1)*p; the vertical coordinate formula for the weld bead: Zj = (j-1)*p; calculate the horizontal and vertical coordinates (Xi, Zj) of the j-th weld bead in the i-th layer.

[0042] Optionally, after calculating and arranging the weld passes on both sides of the vertical stiffener plate based on the K-type groove size information, the method further includes:

[0043] Based on the weld layers on both sides of the vertical stiffener, the welding gun posture angle corresponding to each weld layer is calculated for each welding gun, including:

[0044] Set the gun posture angle Q11 of the first weld pass in the first layer as the initial angle, and use the first angle formula:

[0045] Q11 = h + pk / 2;

[0046] The initial angle is calculated, where h is the normal welding angle and pk is the bevel angle;

[0047] The gun posture angle of the first weld pass in each layer is denoted as Qi1, where i is ≥2. Qi1 is an integer. When 2≤i<n, the second angle formula is used:

[0048] Qi1 = Q11 - (i-1) * sj;

[0049] The gun pose angle of the first weld pass in each layer is calculated, where sj is the set angle;

[0050] When n≤i≤m, Qi1=40°, m is the first weld pass of the last layer, and n is the first weld pass of any layer between the second layer and the last layer;

[0051] The gun posture angle of any weld bead is calibrated as Qij, which is the gun posture angle of the j-th weld bead in the i-th layer. The gun posture angle of any weld bead is calculated using the third angle formula Qij=Qi1+(j-1)*sj.

[0052] The gun angle of the last weld pass in each layer is set to be greater than the initial angle.

[0053] The technical effects of this invention include at least the following:

[0054] The welding equipment of this invention utilizes a rotary driver to drive a crossbeam to rotate relative to a column. During welding operations, the crossbeam rotates above the worktable and then moves relative to the worktable via a base on a ground rail. This movement causes a first vision detector to perform overall visual recognition of the workpiece on the worktable, obtaining a 3D point cloud of the workpiece. The 3D point cloud information of the workpiece is then matched with multiple stored theoretical workpiece models to identify the corresponding theoretical model and determine the weld position based on it. Two moving seats are then controlled to move to their corresponding positions, and two robotic arms drive corresponding second vision detectors along the determined weld position to perform precise visual recognition of the weld, thereby obtaining K-groove dimension information, such as groove angle, groove depth, and groove root gap. Based on the obtained K-groove dimension information, the welding layers are autonomously calculated and arranged. Then, two welding torches are used to perform double-sided, double-arc, multi-layer, multi-pass welding of the weld according to the autonomously calculated and arranged layers. Simultaneously, the two second vision detectors acquire real-time images of the weld at the tip of the welding torches. This enables highly efficient multi-layer, multi-pass welding.

[0055] In this way, the combination of columns, beams, two robotic arms, a first vision detector, two second vision detectors, two moving seats, a base, a ground rail, a worktable, and a rotary actuator significantly improves the welding efficiency of double-sided double-arc welding. In particular, by using the rotary actuator to rotate the beam relative to the column, interference between the beam and the worktable during hoisting and assembly can be avoided without moving the column, thus improving the hoisting and assembly efficiency of the workpiece.

[0056] Most existing weld bevel penetration processes require root cleaning to avoid common weld inclusions and incomplete fusion. This step is usually done manually, which is inefficient. While other existing equipment is mostly semi-automated, it still requires root cleaning. This embodiment uses a dual-gun, double-sided, double-arc welding method, eliminating the root cleaning step and simplifying the welding process while ensuring weld quality. Attached Figure Description

[0057] Figure 1 This is a schematic perspective view of the welding equipment according to a specific embodiment of the present invention;

[0058] Figure 2 A schematic top view of the welding equipment according to a specific embodiment of the present invention;

[0059] Figure 3 This is another schematic top view of the welding equipment according to a specific embodiment of the present invention;

[0060] Figure 4 This is a schematic perspective view of the rotating connection between the column and the crossbeam of the welding equipment according to a specific embodiment of the present invention.

[0061] Figure 5 This is a schematic side view of the rotating connection between the column and the crossbeam of the welding equipment according to a specific embodiment of the present invention.

[0062] Figure 6 This is a schematic perspective view showing the alternating arrangement of a first line scan detector and a second line scan detector in the welding equipment according to a specific embodiment of the present invention.

[0063] Figure 7 This is a schematic flowchart illustrating the main steps of the welding method according to a specific embodiment of the present invention.

[0064] Figure 8 A schematic perspective view of a welded workpiece according to a specific embodiment of the present invention;

[0065] Figure 9 This is a schematic diagram of the three-dimensional point cloud at the bevel of the welded workpiece according to a specific embodiment of the present invention.

[0066] Figure 10 This is a schematic diagram of the layer arrangement of the welding method according to a specific embodiment of the present invention;

[0067] Figure 11 This is a schematic diagram of the welding torch posture angle transformation in the welding method described in a specific embodiment of the present invention.

[0068] Figure 12 This is a schematic diagram illustrating the change in the welding torch posture angle of the welding method described in a specific embodiment of the present invention. Detailed Implementation

[0069] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of the embodiments of the present invention. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. The embodiments of the present invention can be implemented in many ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0070] Unless otherwise defined, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used in this invention and in its specification is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

[0071] See Figures 1 to 12 This embodiment provides a multi-layer, multi-pass intelligent welding device based on double-sided double-arc design, including: a column 11, a crossbeam 12, two robotic arms 13, a first vision detector, two second vision detectors 132, two movable seats 14, a base 15, a ground rail 16, a worktable 17, and a rotary actuator. The ground rail 16 is disposed beside the worktable 17, and the base 15 is used for reciprocating movement along the ground rail 16. The column 11 is fixed on the base 15, one end of the crossbeam 12 is disposed on the top of the column 11, and the rotary actuator is disposed on the top of the column 11. The rotary actuator is used to drive the crossbeam 12. The beam 12 rotates in the horizontal plane. Two movable seats 14 are respectively located at the two long sides of the beam 12. Each robotic arm 13 is located at one of the movable seats 14. Each robotic arm 13 has a welding torch 131 at its end. Each second vision detector 132 is located at the end of one robotic arm 13. The first vision detector is located at the beam 12. The movable seats 14 are used to reciprocate along the beam 12. The second vision detector 132 is used to detect the front of the corresponding welding torch 131. The first vision detector is used to detect the workpiece on the worktable 17.

[0072] It should be noted that the workpiece in this embodiment can be a steel plate, and a fixing tool is used to fix the vertical stiffener 6 to the steel plate so that a K-shaped bevel is maintained between the vertical stiffener 6 and the steel plate. Of course, the bevel between the workpieces can also be an X-shaped bevel, as long as the crossbeam 12 can drive the two moving seats 14 and the robotic arm 13, and be processed by the welding torch 131.

[0073] Alternatively, the base can be moved back and forth on the ground rail using a rack and pinion mechanism and a drive motor. Similarly, the movable seat can also move relative to the crossbeam using a rack and pinion mechanism and a drive motor.

[0074] In addition, the movable seat 14 is fixed to the crossbeam 12 by a linear guide rail.

[0075] In addition, the second visual detector 132 can be a line-scanning visual recognition device composed of a line-scanning laser and a CCD camera, used to visually recognize a designated area at a designated position in front of the welding torch 131.

[0076] The welding equipment of the present invention utilizes a rotary driver to drive the crossbeam 12 to rotate relative to the column 11, so that during the welding operation, the crossbeam 12 rotates above the worktable 17, and then moves on the ground rail 16 via the base 15, causing the crossbeam 12 to move relative to the worktable 17, thereby driving the first vision detector to perform overall visual recognition of the workpiece on the worktable 17 to obtain the three-dimensional point cloud of the workpiece. Then, the three-dimensional point cloud information of the workpiece is matched with multiple stored workpiece theoretical model information to find the corresponding workpiece theoretical model, and the weld position is determined based on the workpiece theoretical model. Then, the two movable seats 14 are moved to their corresponding positions, and the two robotic arms 13 drive the corresponding second vision detectors 132 along the determined weld position to perform precise visual recognition of the weld, thereby obtaining the K-groove size information, such as the groove angle, groove depth, and groove root gap, etc. Based on the obtained K-groove size information, the welding layers are autonomously calculated and arranged. Then, two welding torches 131 are used to perform double-sided, double-arc, multi-layer, multi-pass welding of the weld according to the autonomously calculated and arranged layers. At the same time, the two second vision detectors 132 perform real-time image acquisition of the weld at the front end of the welding torches 131. This achieves high-efficiency multi-layer, multi-pass welding.

[0077] In this way, the combination of column 11, crossbeam 12, two robotic arms 13, first vision detector, two second vision detectors 132, two moving seats 14, base 15, ground rail 16, worktable 17 and rotary drive greatly improves the welding efficiency of double-sided double arc welding. In particular, by rotating the crossbeam 12 relative to the column 11 through the rotary drive, interference of the crossbeam 12 with the worktable 17 during hoisting and assembly can be avoided without moving the column 11, thus improving the hoisting and assembly efficiency of the workpiece.

[0078] Most existing weld bevel penetration processes require root cleaning to avoid common weld inclusions and incomplete fusion. This step is usually done manually, which is inefficient. While other existing equipment is mostly semi-automated, it still requires root cleaning. This embodiment uses a dual-gun, double-sided, double-arc welding method, eliminating the root cleaning step and simplifying the welding process while ensuring weld quality.

[0079] See Figures 1 to 12 Furthermore, the rotary drive includes a servo motor, a bearing, a large gear, and a small gear. The servo motor is located at the top of the column 11, the bearing is located at the rotatable connection between the column 11 and the crossbeam 12, the large gear is located at one end of the crossbeam 12, the small gear meshes with the large gear, the small gear is connected to the output shaft of the servo motor, and the bearing is a deep groove ball bearing.

[0080] A servo motor drives a small gear to rotate a large gear, thereby driving the crossbeam 12 to rotate. At the same time, a deep groove ball bearing is used to cope with the overturning moment of the bearing during rotation, ensuring the smooth rotation of the crossbeam 12.

[0081] See Figures 1 to 12 Furthermore, the worktables 17 are an even number and arranged in pairs on the left and right sides of the ground rail 16, and multiple pairs of worktables 17 are arranged along the extension direction of the ground rail 16.

[0082] The column 11, crossbeam 12, two robotic arms 13, a first vision detector, two second vision detectors 132, two moving seats 14, base 15, worktable 17 and rotary drive constitute a welding workstation, and multiple welding workstations are arranged sequentially on the ground rail 16.

[0083] First, by arranging multiple workstations between multiple pairs of worktables 17, and utilizing the rotatable feature of the crossbeam 12, the crossbeam 12 can be rotated to the left or right worktable 17 as needed. Then, the corresponding two robotic arms 13 of each welding workstation perform welding or visual inspection on the corresponding parts of the workpiece, significantly improving the utilization efficiency of each welding workstation. This enhances the utilization rate and welding efficiency of the entire welding equipment.

[0084] See Figures 1 to 12Furthermore, the column 11 is a shell structure with an internal cavity. A side thread hole 111 is provided on the side wall of the column 11, communicating with the cavity inside the column 11. A first top thread hole 121 is provided at the top of one end of the crossbeam 12, communicating with the cavity of the column 11. A second top thread hole 141 is provided at the top of the movable base 14, communicating with the bottom surface of the movable base 14. A wire spool 151 is provided at the base 15 for storing welding wire 122.

[0085] The welding wire 122 extends from the wire spool 151 and is inserted into the side wire hole 111. Then it passes through the cavity and extends from the top of the crossbeam 12 through the first top wire hole 121. It is then fed into the two second top wire holes 141, passes through the moving seat 14, and is fed along the robotic arm 13 into the corresponding welding gun 131. A bracket 123 is provided at the top of one end of the crossbeam 12. The welding wire 122 is suspended from the top of the bracket 123. The side walls of the first top wire hole 121, the second top wire hole 141, and the side wire hole 111 are all fitted with nylon sleeves. The nylon sleeves are used to cover the welding wire 122.

[0086] Furthermore, the inventors of this invention discovered during the use of the welding equipment that, since welding torches 131 are installed at both robotic arms 13, the welding wire 122 needs to be fed to the two welding torches 131 after passing through one end of the crossbeam 12. During the rotation of the crossbeam 12, the welding wire 122 can become entangled at one end of the crossbeam 12. Especially since the crossbeam 12 rotates back and forth between the two worktables 17, the repeated entanglement of the welding wire 122 can cause it to tensile breakage or snap, resulting in the interruption and cessation of the welding operation.

[0087] To address this emerging problem, this embodiment provides a first top screw hole 121 at one end of the crossbeam 12, which communicates with the cavity of the column 11. The column 11 has a side screw hole 111 on its side wall, and a second top screw hole 141 at the top of the moving seat 14. The welding wire 122 extends from the wire spool 151 and is inserted into the side screw hole 111. It then passes through the cavity, extends from the top of the crossbeam 12 through the first top screw hole 121, and is fed into the two second top screw holes 141, then through the moving seat 14 and along the robotic arm 13 to the corresponding welding torch 131. A bracket 123 supports the welding wire 122 to prevent it from becoming too long and tangling. Furthermore, the sidewalls of the first top screw hole 121, the second top screw hole 141, and the side screw hole 111 are all fitted with nylon sleeves to prevent the sharp walls of the top screw hole and the side screw hole 111 from damaging the welding wire 122.

[0088] Preferably, the side wire holes are located on the front or rear side of the column. This is to adequately accommodate the lateral swaying of the crossbeam relative to the column and to effectively eliminate the entanglement and bending force of the welding wire.

[0089] In this way, no matter how the crossbeam 12 rotates, the bracket 123, the first top screw hole 121, the second top screw hole 141, the side screw hole 111 and the nylon sleeve work together to allow the welding wire 122 to pass directly from the top of the column 11 through one end of the crossbeam 12, preventing the welding wire 122 from getting tangled during the rotation of the crossbeam 12 and ensuring that the welding wire 122 will not be damaged.

[0090] See Figures 1 to 12 Furthermore, the welding equipment also includes two inductive switches 31, two fixed limit blocks 32, a rotation limit block 33, and a rotation controller. The output shaft of the servo motor is equipped with a torque sensor, which is used to detect the torque of the servo motor's output shaft.

[0091] Two fixed limiting blocks 32 are respectively disposed on the left and right sides of the top of the column 11. Each inductive switch 31 is disposed in front of one of the fixed limiting blocks 32 and spaced apart from it. The rotating limiting block 33 is disposed at one end of the crossbeam 12 and is disposed on the axis of the crossbeam 12.

[0092] The rotation limiting block 33 is used to rotate with the crossbeam 12 between the two fixed limiting blocks 32.

[0093] When the rotation limit block 33 passes the inductive switch 31, the inductive switch 31 is triggered and sends a signal.

[0094] The two inductive switches 31, the torque sensor, and the servo motor are respectively connected to the rotation controller;

[0095] The rotation controller is used to control the rotation of the servo motor, and based on the signal emitted by the inductive switch 31, to control the servo motor to decelerate, and when the torque detected by the torque sensor is greater than the set value, to control the servo motor to continue to rotate and output at low power.

[0096] The inventors of this invention discovered that although the crossbeam 12 can rotate, the crossbeam 12 is also equipped with many devices such as two robotic arms 13, two moving seats 14, and two welding torches 131, resulting in a large overall weight and mass. During the process of the crossbeam 12 rotating to its position and stopping, due to the large inertia of the crossbeam 12, it cannot stop immediately when it reaches the designated position, causing a serious angular deviation in the crossbeam 12. This leads to a positioning deviation in the two robotic arms 13 on the crossbeam 12, affecting the positioning accuracy of automatic welding.

[0097] To address this newly discovered problem, before the crossbeam 12 rotates to the designated position and stops, the sensor switch 31 detects that the crossbeam 12 is approaching the stop position and controls the servo motor to begin deceleration. A fixed limit block 32 is placed at the positioning point of the crossbeam 12 to block and limit the rotation limit block 33 at one end of the crossbeam 12, preventing the crossbeam 12 from continuing to rotate. Furthermore, during this process, a torque sensor monitors the rotation status of one end of the crossbeam 12 in real time and adjusts the deceleration force of the servo motor until the rotation limit block 33 touches the fixed limit block 32.

[0098] Meanwhile, due to the gap between the teeth of the large and small gears, even if the servo motor stops rotating when the crossbeam 12 rotates to the designated position, this gap will still cause the crossbeam 12 to sway slightly relative to the column 11. This will cause the two robotic arms 13 to shake along with the crossbeam 12 during operation, affecting the detection accuracy of the first and second vision detectors 132. To address this, this embodiment uses a torque sensor to continuously monitor the output torque of the servo motor in real time, ensuring that the servo motor remains in a rotating state. Even if the rotation limit block 33 is restricted from moving by the fixed limit block 32, the servo motor still maintains its driving state and continues to output torque at a low level. At this time, the torque detected by the torque sensor is greater than the set value, and the controller causes the servo motor to continue rotating and outputting at low power, so that the teeth of the small gear always push against the large gear, eliminating the aforementioned gap and preventing the crossbeam 12 from swaying slightly.

[0099] This ensures the detection accuracy of the first and second visual detectors 132, as well as the welding accuracy of the two welding torches 131.

[0100] See Figures 1 to 12 Furthermore, the first visual detector includes a plurality of first line scan detectors 4 and a plurality of second line scan detectors 5.

[0101] The first line scan detector 4 includes a first boom 42, a first line scan laser 43, and a first camera 41. The first boom 42 is suspended at the bottom surface of the crossbeam 12. The first line scan laser 43 is located at the front end of the first boom 42, and the first camera 41 is located at the rear end of the first boom 42.

[0102] The second line scan detector 5 includes a second boom 52, a second line scan laser 53, and a second camera 51. The second boom 52 is suspended at the bottom surface of the crossbeam 12. The second line scan laser 53 is located at the rear end of the second boom 52, and the second camera 51 is located at the front end of the second boom 52. Multiple first line scan detectors 4 and second line scan detectors 5 are arranged alternately along the long side of the crossbeam 12.

[0103] When the crossbeam 12 is positioned above the worktable 17, multiple first line-scanning lasers 43 irradiate the front of the crossbeam 12 with first line lasers. These first line lasers are arranged parallel or collinearly to each other. Multiple first cameras 41 are used to capture images of the front of the crossbeam 12. The images captured by the first cameras 41 contain the first line lasers, and the image acquisition areas of the multiple first cameras 41 extend along the long front side of the crossbeam 12.

[0104] Multiple second-line scanning lasers 53 irradiate the rear of the crossbeam 12 with second-line lasers. These lasers are arranged parallel or collinearly. Multiple second cameras 51 are used to capture images of the rear of the crossbeam 12. The images captured by the second cameras 51 contain the second-line lasers. The image acquisition area of ​​the multiple second cameras 51 extends along the long rear side of the crossbeam 12.

[0105] Each of the first boom 42 and each of the second boom 52 intersects the crossbeam 12 at the same first predetermined angle in the horizontal plane.

[0106] During the process of visually recognizing the workpiece on the worktable 17 using a conventional line-scan laser image acquisition device, some of the vertical stiffeners 6 on the workpiece surface have their long sides intersecting the extension direction of the ground rail 16. In other words, the extension direction of the long side of the vertical stiffener 6 is not parallel to the moving direction of the crossbeam 12. This causes the conventional line-scan laser vision inspection equipment to be unable to acquire the weld seams behind these vertical stiffeners 6, resulting in an incomplete 3D point cloud generated based on the first vision detector, which cannot match the pre-stored theoretical model of the workpiece.

[0107] To address this issue, this embodiment employs multiple first line scan detectors 4 to visually detect the worktable 17 on the front side of the crossbeam 12, while multiple second line scan detectors 5 visually detect the worktable 17 on the rear side of the crossbeam 12. Thus, when the crossbeam 12 moves forward relative to the worktable 17, although the rear of the aforementioned vertical stiffener 6 cannot be identified due to the forward movement of the multiple first visual detectors, when the crossbeam 12 passes the rear of the aforementioned vertical stiffener 6, the second visual detector 132, positioned at the rear of the crossbeam 12 and performing image acquisition backward, can identify the shape of the rear of the aforementioned vertical stiffener 6 and the corresponding weld position. Then, the image information detected by the first and second visual detectors 132 is stitched together at equal distances according to the deviation distance between the image acquisition areas of the first and second visual detectors 132, thereby obtaining complete three-dimensional point cloud information of the workpiece.

[0108] Furthermore, each of the first boom 42 and each of the second boom 52 intersects the crossbeam 12 at the same predetermined angle in the horizontal plane, ensuring the integrity and accuracy of the visual detection information stitching from multiple first line scan detectors 4 and second line scan detectors 5, and preventing the stitched images from overlapping. This compensates for blind spots in visual detection.

[0109] Furthermore, by utilizing the fact that each of the first boom 42 and each of the second boom 52 intersects the crossbeam 12 at the same predetermined angle in the horizontal plane, the first line scan detector 4 and multiple second line scan detectors 5 can detect the root weld positions of most of the vertical stiffeners. This ensures accurate visual inspection of the workpiece and prevents incomplete point clouds generated from the workpiece.

[0110] Preferably, the first set angle is between 5 and 20 degrees.

[0111] See Figures 1 to 12 Furthermore, the colors of the first line laser emitted by any two adjacent first line-scan lasers 43 are different, and a first filter is provided at the lens of each first camera 41. The first filter is used to receive only the first line laser emitted by the first line-scan laser 43 located at the same first boom 42.

[0112] The colors of the second line laser emitted by any two adjacent second line scan lasers 53 are different. A second filter is provided at the lens of each second camera 51. The second filter is used to receive only the second line laser emitted by the second line scan laser 53 at the same second boom 52.

[0113] For example, in six positions from one end of the crossbeam 12 to the other, the first, third, and fifth positions are respectively equipped with first line scan detectors 4, and the second, fourth, and sixth positions are respectively equipped with second line scan detectors 5, so that the first line scan detectors 4 and second line scan detectors 5 are arranged alternately. Specifically, the first line scan lasers 43 at the first and fifth positions emit green lasers, while the first line scan laser 43 at the third position emits red lasers; similarly, the second line scan lasers 53 at the second and sixth positions emit green lasers, while the second line scan laser 53 at the fourth position emits red lasers. Furthermore, the filters at the first and fifth positions, and the second and sixth positions can only detect green lasers, while the filters at the third and fourth positions can only detect red lasers.

[0114] During use, it was found that because the lasers emitted by the first line scan detectors 4 that are separated by one are in the same position or the same adjacent area, the first camera 41 of one first line scan detector 4 recognizes the line laser emitted by the first line scan laser 43 of another first line scan detector 4 that is separated by one, resulting in visual acquisition errors.

[0115] To address this issue, this embodiment employs a first filter that only receives line lasers emitted by the first line-scan laser 43 located at the same first boom 42, and a second filter that only receives line lasers emitted by the second line-scan laser 53 located at the same second boom 52. Furthermore, the colors of the first line-scan lasers 43 at any two adjacent first line-scan detectors 4 and the colors of the second line-scan lasers 53 at any two adjacent second line-scan detectors 5 are different. Specifically, the first line-scan lasers 43 at the first and fifth positions emit green lasers, while the first line-scan laser 43 at the third position emits red lasers; the second line-scan lasers 53 at the second and sixth positions emit green lasers, while the second line-scan laser 53 at the fourth position emits red lasers. The filters at the first and fifth positions, and the second and sixth positions, can only detect green lasers, while the filters at the third and fourth positions can only detect red lasers.

[0116] This prevents visual acquisition errors and prevents the third position from emitting a green laser, which is then incorrectly identified by the first and fifth positions. It ensures that each first camera 41 and second camera 51 can only acquire the line laser emitted by the line scan laser located on the same boom.

[0117] See Figures 1 to 12 Furthermore, the top of the column 11 is a cylindrical structure, and the top sidewall of the column 11 has multiple threaded holes 112. The multiple threaded holes 112 are evenly distributed along the circumference of the cylinder, and the inductive switch 31 is located in front of the multiple threaded holes 112.

[0118] One end of the fixed limiting block 32 is connected to a handle, and the other end is connected to a bolt. The bolt is used for threaded connection to any one of the plurality of threaded holes 112, one of which is a reference hole. When the bolt is connected to the reference hole, and the rotation limiting block 33 is blocked by the fixed limiting block 32, the crossbeam 12 is in a reference position. The crossbeam 12 in the reference position is perpendicular to the movement direction of the base 15.

[0119] When the bolt is connected to other threads, and the rotation limit block 33 is blocked by the fixed limit block 32, the position of the crossbeam 12 is tilted at different angles in the horizontal plane relative to the reference position, so that the visual detection direction of the multiple first line scan detectors 4 and the multiple second line scan detectors 5 in the horizontal plane is tilted at different angles relative to the moving direction of the base 15, and the corresponding different angles are calculated by the servo motor.

[0120] Considering that the angles between the multiple vertical stiffeners 6 on the top surface of the workpiece and the moving direction of the base 15 frequently change depending on the type of workpiece, multiple first line scan detectors 4 and multiple second line scan detectors 5 are still subject to occlusion, resulting in partial loss of the generated point cloud.

[0121] To this end, the fixed limiting block 32 is detachably connected to the corresponding threaded hole 112 via threads, allowing the crossbeam 12 to tilt forward or backward relative to the reference position at different angles. This enables multiple first line scan detectors 4 and multiple second line scan detectors 5 to visually identify the back of the vertical stiffener 6 at various angles, and calculate the accurate angle of tilt of the crossbeam 12 relative to the reference position by converting the angle of rotation of the servo motor. Alternatively, the positions of the multiple threaded holes 112 can be preset in advance. For example, there can be a total of five threaded holes 112 arranged sequentially from front to back along the circumference of the top of the column 11, with an included angle of 10 degrees between each threaded hole 112, and the third threaded hole 112 in the center serving as the reference hole. Based on this, the angle of the visual recognition information from the multiple first line scan detectors 4 and multiple second line scan detectors 5 is adjusted to restore the generated 3D point cloud to a normal angle state. Furthermore, the fixed limiting block 32 can be easily switched between the multiple threaded holes 112 using a handle.

[0122] In this way, by rotating the crossbeam 12 and combining the first line scan detector 4 and the second line scan detector 5, accurate visual detection and recognition of the vertical stiffeners 6 at various angles are achieved, ensuring the accuracy of the 3D point cloud generation.

[0123] In addition, this embodiment also provides a welding method, which uses the aforementioned welding equipment, and the welding method includes:

[0124] The crossbeam 12 is rotated to a position parallel to the ground rail 16 by a rotary drive, and the workpiece is hoisted onto the worktable 17. The workpiece is provided with multiple vertical stiffeners 6.

[0125] The crossbeam 12 is rotated to a position perpendicular to the ground rail 16 by the rotary driver and moved by the base 15, so that the first vision detector can obtain the three-dimensional point cloud of the workpiece.

[0126] Visual inspection of bevel information: Based on the three-dimensional point cloud, the base 15, the two moving seats 14 and the robotic arm 13 move in coordination, so that the two second visual detectors 132 can obtain the K-shaped bevel size information at the vertical stiffener 6;

[0127] Arrangement of weld layers: Based on the K-type groove size information, calculate and arrange the weld layers on both sides of the vertical stiffener 6;

[0128] Multi-layer multi-pass welding: Based on the layer arrangement of the weld seams on both sides of the vertical stiffener 6, two welding guns 131 are used to perform multi-layer multi-pass welding on the weld seams on both sides of the vertical stiffener 6 respectively.

[0129] The visual inspection of the bevel information is performed on each of the multiple vertical stiffeners 6 to achieve the multi-layer, multi-pass welding.

[0130] It should be noted that the vertical stiffener 6 in this embodiment can be erected and fixed to the top of the workpiece using tooling fixtures. For example, a T-joint can be used to fix the vertical stiffener 6.

[0131] In addition, by using double-sided double-arc synchronous welding, full penetration of the weld seams on both sides of the vertical stiffener 6 is achieved, resulting in high welding quality and high efficiency of double-sided double-arc welding.

[0132] See Figures 1 to 12 Furthermore, based on the K-type groove size information, the weld layers on both sides of the vertical stiffener 6 are calculated and arranged as follows:

[0133] Based on the K-type bevel size information, bevel data for the bevel angle, bevel depth, and bevel root gap of each V-type bevel of the K-type bevel are calculated.

[0134] Determine the weld leg size based on the bevel data or manual settings;

[0135] Based on the bevel root gap and the weld leg size, the thickness and number of the first weld bead are determined, and the thickness of each subsequent weld bead is equal to the weld leg size.

[0136] The number of weld beads in each layer after the first layer is calculated using the formula: Ai = Ji / p + 1. Ai is the number of weld beads in the i-th layer, i ≥ 2, Ji is the root gap of the i-th layer, p is the weld bead size, and Ji / p is an integer.

[0137] It should be noted that the root gap can refer to the distance between the two plates at the root of the bevel when they are not welded. When the root gap increases, it is equivalent to an equal increase in all heights of the bevel in the horizontal direction.

[0138] Additionally, the weld leg size can refer to the minimum distance from the weld toe on one right-angled face to the surface of another right-angled face in the cross-section of a fillet weld during welding.

[0139] For example, if the gap at the root of the bevel is small, such as 6mm, then the thickness of the first weld bead can be 7mm, and the thickness of each subsequent weld bead, that is, the weld leg size, can be set to 5mm.

[0140] Using the layer number formula Ai = Ji / p + 1, the second layer is calculated as 5 divided by 5 plus 1, which equals 2, meaning the second layer has 2 weld passes. This process is repeated to obtain the third layer, which has 3 weld passes. During the follow-up process of the welding torch 131, the second vision detector 132 visually identifies a designated area at a specified position in front of the welding torch 131, thus knowing in advance the root gap Ji of the i-th layer at the bevel in front of the welding torch 131. In this way, the second vision detector 132 visually detects the bottom surface of the bevel in front of the welding torch 131 in advance. Combined with the simplicity of the layer number formula, the number of weld passes in each layer can be quickly calculated.

[0141] Next, the root of the bevel is set as the zero point of the coordinate system. The horizontal coordinate formula of the weld bead is: Xi = (i-1)*p; the vertical coordinate formula of the weld bead is: Zj = (j-1)*p; the horizontal and vertical coordinates (Xi, Zj) of the j-th weld bead in the i-th layer are calculated.

[0142] For example, with the root of the bevel as the zero point (0 for horizontal and 0 for vertical), the horizontal and vertical coordinates (0, 0) of the first weld bead in the first layer are calculated, the weld leg size is 5mm, and the offset position of the second pass in the third layer is (10, 5).

[0143] In this way, by using only two second vision detectors 132 to independently visually identify the two V-shaped bevels of the K-type bevel, and by visually identifying the root gap of the next weld pass in advance during each weld pass welding process, and by using only simple arithmetic formulas such as addition, subtraction, multiplication, and division, the coordinate position of each weld pass and the number of weld passes per layer of the bevel can be calculated. This significantly simplifies the automatic pass routing calculation for multi-layer, multi-pass welding based on real-time vision detection. It also improves the adaptability of vision-based multi-layer, multi-pass automatic welding.

[0144] See Figures 1 to 12 Furthermore, after calculating and arranging the weld passes on both sides of the vertical stiffener 6 based on the K-type groove size information, the process further includes:

[0145] Based on the weld layers on both sides of the vertical stiffener 6, the gun posture angle corresponding to each weld bead welded by each welding gun 131 is calculated, including:

[0146] Set the gun posture angle Q11 of the first weld bead of the first layer as the initial angle, and use the first angle formula: Q11=h+pk / 2; calculate the initial angle, where h is the normal welding angle and pk is the bevel angle;

[0147] The gun posture angle of the first weld pass in each layer is marked as Qi1, where i is ≥2. Qi1 is an integer. When 2≤i<n, the second angle formula is used: Qi1=Q11-(i-1)*sj;

[0148] The gun posture angle of the first weld pass in each layer is calculated, where sj is the set angle; when n≤i≤m, Qi1=40°, m is the first weld pass of the last layer, and n is the first weld pass of any layer between the second layer and the last layer;

[0149] The gun posture angle of any weld bead is calibrated as Qij, which is the gun posture angle of the j-th weld bead in the i-th layer. The gun posture angle of any weld bead is calculated using the third angle formula Qij=Qi1+(j-1)*sj.

[0150] The gun angle of the last weld pass in each layer is set to be greater than the initial angle.

[0151] Preferably, the gun angle of the last weld pass in each layer is 70 to 90 degrees.

[0152] For example, 45 degrees is the normal welding angle, and the bevel angle is also 45 degrees. The initial angle is the welding angle of the first pass of the first layer, which is 45 degrees + 22.5 degrees. Starting from the second layer, the angle of the first pass of each layer is the initial angle minus 5 degrees, that is, sj = 5 degrees. The angle of the first pass of the third layer is minus 10 degrees, and so on, until it is reduced to 40 degrees and no longer decreases. The angle of the first pass of subsequent layers is 40 degrees. The angle of the second pass is the angle of the first pass of each layer plus 5 degrees, the angle of the third pass plus 10 degrees, and the angle of the intermediate layers is increased by 5 degrees based on the first pass.

[0153] Setting the welding torch angle prevents interference between the tail of the welding torch 131 and the end of the rack and pinion robotic arm 13 and the workpiece during welding, thus avoiding collisions, especially with other vertical stiffeners. Adjusting the torch angle also ensures the integrity of the weld bead. The torch angle is adjusted according to the number of layers, with a minimum angle of 40 degrees. Once 40 degrees is reached, the torch angle for the first pass of each subsequent layer increases sequentially.

[0154] Furthermore, considering the limitations and interference experienced by the first pass of each layer's welding angle, the welding angle of the first pass in each layer is calculated first, and then the other welding angles for each layer are calculated based on the welding angle of the first pass. Moreover, the formula for calculating the welding angle is simple, allowing for real-time adjustment of the welding angle according to the welding position, avoiding complex calculations that could lead to interference or collisions due to untimely adjustment of the welding angle.

[0155] It should be noted that the gun position angle here refers to the gun position angle in a vertical plane perpendicular to the direction of weld extension.

[0156] Furthermore, considering that the upper weld bead, which is the last weld bead of each layer, is prone to undercut defects during welding, a method is used to eliminate undercut defects by setting the torch angle of the last weld bead of each layer to be greater than the initial angle. This results in the torch 131 being slightly inverted. Simultaneously, this ensures a smooth transition for this weld bead.

[0157] In addition, to address the issue of poor full penetration at the weld root, the similarity in beveling techniques between shipbuilding and steel structures is utilized. Different beveling methods are employed for plates of varying thicknesses. For example, the common single V-groove leaves an appropriate gap (5mm) at the root to ensure penetration, and ceramic or metal backings are used to ensure proper forming. Alternatively, oscillating welding can be employed, where the welding torch 131 oscillates during the welding process to increase the heating area and time of the arc on the base material, thereby ensuring penetration at the weld root.

[0158] In addition, for thicker plates, to reduce the amount of beveling welding, for K-type or X-type beveling, no gap or a gap of less than 2mm is left at the root of the workpiece assembly. A double-sided, double-arc design is used, which eliminates the root cleaning process, improving welding efficiency while ensuring welding quality.

[0159] In addition, a weld is generated on each side of the K-groove workpiece at the position to be welded. Based on the preliminary weld information extracted by the first vision detector, an initial detection point of the welding torch 131 is generated outside the safe distance of the workpiece. Then, the two robotic arms 13 use the second vision detector 132 at the welding torch 131 to accurately scan the groove welds on both sides of the long side of the vertical stiffener 6. Each robotic arm generates a corresponding weld bead point cloud map and calculates the layer of welds arranged on both sides of the vertical stiffener 6.

[0160] There are numerous applications of medium and thick plate components in shipbuilding and steel structure, such as columns and beams in typical steel structures, the bottom, sides, and longitudinal and transverse bulkheads of ships, and the segmented joints of various parts of ships. The welding of these thick plates, similar to box beams, often results in large errors due to deviations in bevel cutting and workpiece assembly from various manufacturers. This leads to significant discrepancies with the originally designed bevel parameters, making it impossible to weld according to the originally set multi-layer, multi-pass welding parameters. Consequently, the previously set process parameters are not universal. Therefore, a first vision detector and a second vision detector 132 are combined. The second vision detector 132 collects the actual bevel dimensions, and based on the actual bevel dimension information, the corresponding weld beads are generated layer by layer during the multi-layer, multi-pass welding process.

[0161] In addition, during welding, the robotic welding torch 131 is positioned on both sides of the vertical stiffener 6 of the T-joint, employing asymmetrical double-sided double-arc MAG welding with a spacing of more than 60mm between the two arcs. One torch moves 60mm first before the other torch initiates its arc. A tracking method is used during welding; a fixed length is measured at the starting point, and the remaining weld bead is welded using laser tracking, measured by a second vision detector 132. Simultaneously, the ending point is automatically searched. The penetration depth and width of the root pass in double-sided double-arc welding are primarily influenced by the power of the front arc, while the rear arc mainly provides post-heating. Therefore, by adjusting the welding parameters of the front arc, full root penetration is achieved, resulting in a single-sided weld with double-sided forming. At a welding speed of 6mm / s, a current of 290A, and a voltage of 30V, a weld with good penetration on both the front and back sides can be obtained.

[0162] While the present invention has been disclosed above, its scope of protection is not limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention, and all such changes and modifications will fall within the scope of protection of the present invention.

Claims

1. A multi-layer, multi-pass intelligent welding device based on double-sided double-arc welding, characterized in that, include: The system comprises a column, a crossbeam, two robotic arms, a first vision detector, two second vision detectors, two movable seats, a base, a ground rail, a worktable, and a rotary actuator. The ground rail is located beside the worktable, and the base is used for reciprocating movement along the ground rail. The column is fixed to the base, and one end of the crossbeam is located on the top of the column. The rotary actuator is located on the top of the column and is used to drive the crossbeam to rotate in a horizontal plane. The two movable seats are respectively located at the two long sides of the crossbeam. Each robotic arm is located at one of the movable seats, and each robotic arm has a welding torch at its end. Each second vision detector is located at the end of one robotic arm, and the first vision detector is located at the crossbeam. The movable seats are used for reciprocating movement along the crossbeam, and the second vision detectors are used to detect the area in front of the corresponding welding torch. The first vision detectors are used to detect the workpiece on the worktable.

2. The welding equipment according to claim 1, characterized in that, The rotary drive includes a servo motor, a bearing, a large gear, and a small gear. The servo motor is located at the top of the column, the bearing is located at the rotatable connection between the column and the crossbeam, the large gear is located at one end of the crossbeam, the small gear meshes with the large gear, and the small gear is connected to the output shaft of the servo motor. The bearing is a deep groove ball bearing. The worktables are an even number and arranged in pairs on the left and right sides of the ground rail, with multiple pairs of worktables arranged along the extension direction of the ground rail. The welding workstation consists of the column, beam, two robotic arms, a first vision detector, two second vision detectors, two moving seats, a base, a worktable, and a rotary drive. Multiple welding workstations are arranged sequentially on the ground rail.

3. The welding equipment according to claim 2, characterized in that, The column is a shell structure with an internal cavity. Side thread holes are formed on the side walls of the column, communicating with the internal cavity. A first top thread hole is formed at the top of one end of the crossbeam, communicating with the cavity of the column. A second top thread hole is formed at the top of the movable base, communicating with the bottom surface of the movable base. A wire spool is provided at the base for storing welding wire. The welding wire extends from the wire spool and is inserted into the side wire hole. It then passes through the cavity and extends from the top of the crossbeam through the first top wire hole. It is then fed into the two second top wire holes, passes through the moving seat, and is fed along the robotic arm into the corresponding welding gun. A bracket is provided at the top of one end of the crossbeam, and the welding wire is suspended from the top of the bracket. Nylon sleeves are fitted on the side walls of the first top wire hole, the second top wire hole, and the side wire hole. The nylon sleeves are used to cover the welding wire.

4. The welding equipment according to claim 3, characterized in that, The welding equipment also includes two inductive switches, two fixed limit blocks, a rotation limit block, and a rotation controller. The output shaft of the servo motor is equipped with a torque sensor, which is used to detect the torque of the servo motor's output shaft. Two fixed limiting blocks are respectively disposed on the left and right sides of the top of the column. Each inductive switch is disposed in front of one of the fixed limiting blocks and spaced apart from it. The rotating limiting block is disposed at one end of the crossbeam and is disposed on the axis of the crossbeam. The rotation limiting block is used to rotate with the crossbeam between the two fixed limiting blocks. When the rotation limit block passes the inductive switch, the inductive switch is triggered and sends a signal. The two inductive switches, the torque sensor, and the servo motor are respectively connected to the rotation controller; The rotation controller is used to control the rotation of the servo motor, and to control the servo motor to decelerate based on the signal emitted by the inductive switch. When the torque detected by the torque sensor is greater than the set value, the controller controls the servo motor to continue to rotate and output at low power.

5. The welding equipment according to any one of claims 1 to 4, characterized in that, The first visual detector includes multiple first line scan detectors and multiple second line scan detectors. The first line scan detector includes a first boom, a first line scan laser, and a first camera. The first boom is suspended from the bottom surface of the crossbeam, the first line scan laser is located at the front end of the first boom, and the first camera is located at the rear end of the first boom. The second line scan detector includes a second boom, a second line scan laser, and a second camera. The second boom is suspended at the bottom surface of the crossbeam, the second line scan laser is located at the rear end of the second boom, and the second camera is located at the front end of the second boom. Multiple first and second line scan detectors are arranged alternately along the long side of the crossbeam. When the crossbeam is positioned above the worktable, multiple first line-scanning lasers irradiate the front of the crossbeam with first line lasers. These first line lasers are arranged parallel or collinearly. Multiple first cameras are used to capture images of the front of the crossbeam. The images captured by the first cameras contain the first line lasers, and the image acquisition areas of the multiple first cameras extend along the long front side of the crossbeam. Multiple second-line scanning lasers irradiate the rear of the crossbeam with second-line lasers. These lasers are arranged parallel or collinearly. Multiple second cameras capture images of the rear of the crossbeam, and these images contain the second-line laser light. The image acquisition areas of the multiple second cameras extend along the long rear side of the crossbeam. Each of the first booms and each of the second booms intersects the crossbeam at the same first predetermined angle in the horizontal plane.

6. The welding equipment according to claim 5, characterized in that, The first line laser emitted by any two adjacent first line-scan lasers is of a different color. Each first camera lens is equipped with a first filter, which is used to receive only the first line laser emitted by the first line-scan laser located at the same first boom. The second line laser emitted by any two adjacent second line scan lasers is of different colors. Each second camera lens is provided with a second filter, which is used to receive only the second line laser emitted by the second line scan laser at the same second boom.

7. The welding equipment according to claim 5, characterized in that, The top of the column is cylindrical, and multiple threaded holes are formed on the top sidewall of the column. These threaded holes are evenly spaced along the circumference of the cylinder, and the inductive switch is located in front of these threaded holes. One end of the fixed limiting block is connected to a handle, and the other end is connected to a bolt. The bolt is used for threaded connection to any one of the plurality of threaded holes, one of which is a reference hole. When the bolt is connected to the reference hole, and the rotating limiting block is blocked by the fixed limiting block, the crossbeam is in a reference position. The crossbeam in the reference position is perpendicular to the direction of movement of the base. When the bolt is connected to other threads, and the rotation limit block is blocked by the fixed limit block, the position of the crossbeam is tilted at different angles in the horizontal plane relative to the reference position, so that the visual detection direction of the multiple first line scan detectors and the multiple second line scan detectors in the horizontal plane is tilted at different angles relative to the moving direction of the base, and the corresponding different angles are calculated by the servo motor.

8. A welding method, wherein the welding method uses the welding equipment according to any one of claims 1 to 7, the welding method comprising: The crossbeam is rotated to a position parallel to the ground rail by a rotary drive, and the workpiece is hoisted onto the worktable. The workpiece is equipped with multiple vertical stiffeners. The crossbeam is rotated to a position perpendicular to the ground rail by the rotary driver, and moved by the base, so that the first vision detector can obtain the three-dimensional point cloud of the workpiece. Visual detection of bevel information: Based on the three-dimensional point cloud, the base, the two moving seats and the robotic arm move in coordination to enable the two second visual detectors to obtain the K-shaped bevel size information at the vertical stiffener. Arrangement of weld layers: Based on the K-groove size information, calculate and arrange the weld layers on both sides of the vertical stiffener. Multi-layer, multi-pass welding: Based on the layer arrangement of the weld seams on both sides of the vertical stiffener, two welding torches are used to perform multi-layer, multi-pass welding on the weld seams on both sides of the vertical stiffener. The step of visually inspecting the bevel information for each of the multiple vertical stiffeners and then performing the multi-layer, multi-pass welding is performed.

9. The welding method according to claim 8, characterized in that, Based on the K-type groove size information, the weld passes on both sides of the vertical stiffener are calculated and arranged as follows: Based on the K-type bevel size information, bevel data for the bevel angle, bevel depth, and bevel root gap of each V-type bevel of the K-type bevel are calculated. Determine the weld leg size based on the bevel data or manual settings; Based on the bevel root gap and the weld leg size, the thickness and number of the first weld bead are determined, and the thickness of each subsequent weld bead is equal to the weld leg size. Using the formula for the number of layers: Ai = Ji / p + 1; Calculate the number of weld beads in each layer after the first layer, where Ai is the number of weld beads in the i-th layer, i≥2, Ji is the root gap of the i-th layer, p is the weld leg size, and Ji / p is an integer. Set the root of the bevel as the zero point of the coordinate system, and use the horizontal coordinate formula for the weld bead: Xi = (i-1)*p; the vertical coordinate formula for the weld bead: Zj = (j-1)*p; calculate the horizontal and vertical coordinates (Xi, Zj) of the j-th weld bead in the i-th layer.

10. The welding method according to claim 9, characterized in that, Based on the K-groove size information, after calculating and arranging the weld passes on both sides of the vertical stiffener, the process further includes: Based on the weld layers on both sides of the vertical stiffener, the welding gun posture angle corresponding to each weld layer is calculated for each welding gun, including: Set the gun posture angle Q11 of the first weld pass in the first layer as the initial angle, and use the first angle formula: Q11 = h + pk / 2; The initial angle is calculated, where h is the normal welding angle and pk is the bevel angle; The gun posture angle of the first weld pass in each layer is denoted as Qi1, where i is ≥2. Qi1 is an integer. When 2≤i<n, the second angle formula is used: Qi1 = Q11 - (i-1) * sj; The gun pose angle of the first weld pass in each layer is calculated, where sj is the set angle; When n≤i≤m, Qi1=40°, m is the first weld pass of the last layer, and n is the first weld pass of any layer between the second layer and the last layer; The gun posture angle of any weld bead is calibrated as Qij, which is the gun posture angle of the j-th weld bead in the i-th layer. The gun posture angle of any weld bead is calculated using the third angle formula Qij=Qi1+(j-1)*sj. The gun angle of the last weld pass in each layer is set to be greater than the initial angle.

Images