Automatic welding equipment and method for horizontal butt joints of large-diameter steel pipes

Abstract

This invention discloses an automatic welding equipment and method for horizontal butt joint circumferential seams of large-diameter steel pipes. The equipment includes an automatic welding host and a transfer trolley for transporting the automatic welding host. The automatic welding host includes a main frame, a welding system, a welding positioning mechanism for connecting the welding system and the main frame, a traveling mechanism for driving the main frame to move axially along the steel pipe, and a host positioning mechanism for fixing the relative position of the main frame and the steel pipe. The traveling mechanism includes a main lifting mechanism for raising and lowering the main frame and a sliding support mechanism mounted on the main frame and movable axially along the steel pipe. The main lifting mechanism and the sliding support mechanism alternately support the main frame to achieve step-by-step movement. The automatic welding host has an integral frame structure and adopts a safe and reliable step-by-step movement. It can adapt to situations where the axes of the two steel pipe sections do not coincide, the straightness of the steel pipe exceeds the standard, or the roundness does not meet the standard, enabling the automatic welding host 1 to successfully complete the automatic welding work.

Description

Technical Field

[0001] This invention relates to the field of pipeline welding technology, and in particular, to an automatic welding device for horizontal butt joints of large-diameter steel pipes. Furthermore, this invention also relates to an automatic welding method for horizontal butt joints of large-diameter steel pipes. Background Technology

[0002] In on-site manufacturing and installation of steel pipes for water conservancy and hydropower projects, steel pipes are typically welded into sections no longer than 6 meters. These pipes are transported to the installation site using specialized truck trailers or railcars, where they are then assembled and welded. On-site welding demands high quality, involves a large workload, and presents significant welding challenges. Currently, welding of the steel pipe assembly seams is primarily done manually. However, manual labor is characterized by high intensity, inconsistent quality, and low efficiency. Traditional manual welding can no longer meet the demands of on-site construction.

[0003] To improve welding efficiency, automatic welding devices for the inner circumferential seams of steel pipes have emerged. Since the assembly of steel pipes relies on a rail-guided trolley, it is difficult to adjust the angle, roundness, assembly spacing, and alignment of the axes of the two sections of steel pipe during the assembly process. This results in problems such as misalignment of the axes between steel pipes and failure to meet the required roundness.

[0004] For example, Chinese patent CN216730166 U discloses an automatic welding device for steel pipes inside tunnels. This device uses a circular sliding assembly to allow the welding torch to move circumferentially along the inner wall of a large steel pipe within the tunnel, thus automatically welding the circular end face of the pipe. However, this device has several drawbacks. First, as construction progresses, the welding workstation constantly changes, and the automatic welding device cannot move autonomously, making construction inside the steel pipe very inconvenient and reducing overall welding efficiency. Second, because the sliding rail is attached to the inner wall of the steel pipe through a positioning module, the circular track is difficult to set up when the roundness of the steel pipe does not meet requirements, leading to situations where welding cannot be effectively performed. Summary of the Invention

[0005] This invention provides an automatic welding device and method for horizontal butt joint circumferential seams of large-diameter steel pipes, to solve the technical problems of existing automatic welding equipment being inconvenient to construct inside steel pipes and difficult to apply when the axes of the steel pipes do not coincide or the roundness of the steel pipes exceeds the standard.

[0006] According to one aspect of the present invention, an automatic welding device for horizontal butt joint circumferential seams of large-diameter steel pipes is provided, comprising an automatic welding host and a transfer trolley for transferring the automatic welding host. The automatic welding host includes a main frame, a welding system, a welding positioning mechanism for connecting the welding system and the main frame, a traveling mechanism for driving the main frame to move axially along the steel pipe, and a host positioning mechanism for fixing the relative position of the main frame and the steel pipe. The traveling mechanism includes a main lifting mechanism for driving the main frame to rise and fall, and a sliding support mechanism arranged on the main frame and movable axially along the steel pipe. The main lifting mechanism and the sliding support mechanism alternately support the main frame to achieve step-by-step movement.

[0007] Furthermore, the main lifting mechanism includes a main lifting slide mounted on the main frame, a main lifting slide slidably connected to the main lifting slide, a main lifting cylinder for driving the main lifting slide to slide vertically relative to the main lifting slide, and a main lifting support shoe mounted on the main lifting slide for abutting against the inner wall of the steel pipe. The main lifting slide is provided with a support shoe slide seat, and the main lifting support shoe is provided with a support shoe slide rail slidably connected to the support shoe slide seat. The support shoe slide seat and the main lifting support shoe are connected by a support shoe translation cylinder.

[0008] Furthermore, the sliding support mechanism includes a slide rail arranged along the axial direction of the steel pipe on the main frame, a sliding seat slidably connected to the slide rail, a sliding support shoe arranged on the sliding seat, and a stepping drive device for driving the sliding seat to translate relative to the slide rail.

[0009] Furthermore, the sliding seat is equipped with a step-crossing hydraulic cylinder for driving the main frame to rise and fall, and a support pad is arranged on the free end of the step-crossing hydraulic cylinder.

[0010] Furthermore, the host positioning mechanism includes a telescopic frame mounted on the main frame, a telescopic rod slidably connected to the telescopic frame, a side support shoe mounted on the free end of the telescopic rod, and a side support cylinder for driving the telescopic rod to move the side support shoe to abut against the inner wall of the steel pipe in a horizontal direction.

[0011] Furthermore, the main unit positioning mechanism also includes a directional hydraulic cylinder. One end of the directional hydraulic cylinder is hinged to the telescopic frame, and the other end is hinged to the side support shoe. The side support shoe is hinged to the free end of the telescopic rod. The angle between the side support shoe and the horizontal plane is adjusted by extending and retracting the directional hydraulic cylinder so that the side support shoe fits against the inner wall of the steel pipe.

[0012] Furthermore, the welding system includes an arc welding mechanism for welding the top and side arcs of the circumferential seam and a flat welding mechanism for welding the bottom arc of the circumferential seam. The arc welding mechanism includes an arc track, an arc rack arranged on the arc track, a traveling trolley arranged on the arc track and adapted to the arc rack, and a first welding robotic arm arranged on the traveling trolley. The first welding robotic arm is equipped with a first welding torch, a first torch cleaner, a first vision system, and a first molten pool monitoring system.

[0013] Furthermore, the welding positioning mechanism includes a mounting base arranged on the main frame, a lifting frame arranged on the mounting base, a floating seat arranged on the free end of the lifting frame, a transverse drive device arranged on the floating seat, a longitudinal drive device arranged on the transverse drive device, and a floating positioning plate arranged on the longitudinal drive device. The lifting frame, the transverse drive device, and the longitudinal drive device are arranged perpendicular to each other, and the transverse drive device or the longitudinal drive device is arranged along the axial direction of the steel pipe. The three arc-shaped welding mechanisms are respectively arranged on the corresponding floating positioning plates. The flat welding mechanism includes a second welding robotic arm arranged on the corresponding floating positioning plate. The second welding robotic arm is equipped with a second welding torch, a second torch cleaner, a second vision system, and a second molten pool monitoring system.

[0014] Furthermore, the main frame is provided with a walkway for observation and / or maintenance. The walkway includes a first walkway that can be raised and lowered in the vertical direction and a second walkway that can be extended and retracted in the horizontal direction. The two second walkways are arranged on both sides of the first walkway, respectively corresponding to the three arc-shaped welding mechanisms.

[0015] Furthermore, the transfer trolley includes a trolley body and a trolley lifting mechanism for driving the trolley body to rise and fall.

[0016] Furthermore, an equipment platform is provided on the main frame, and the equipment platform is equipped with a power supply for providing electricity, a pump station for providing hydraulic oil, and an electrical control cabinet.

[0017] According to another aspect of the present invention, an automatic welding method for horizontal butt joint circumferential seams of large-diameter steel pipes is also provided, comprising the following steps:

[0018] S1, Equipment Inlet Pipe

[0019] S11, the welding system, welding positioning mechanism, main machine positioning mechanism and walkway are all retracted to reduce the maximum external profile of the automatic welding equipment for horizontal butt joint circumferential seams of large-diameter steel pipes. The step-through cylinder of the sliding support mechanism extends and abuts against the body of the transfer trolley. The main frame is supported by the step-through cylinder, and the main lifting support shoe of the main lifting mechanism is suspended in the air.

[0020] S12. The transfer trolley transports the automatic welding equipment for the horizontal butt joint of large-diameter steel pipes to the front end of the steel pipe. The trolley body enters the lower end of the steel pipe cantilever section and extends the trolley lifting mechanism so that the trolley body supports the cantilever section of the steel pipe.

[0021] S13. The stepping drive device of the sliding support mechanism drives one end of the main frame into the steel pipe;

[0022] S14. The main lifting support shoe of the main lifting mechanism extends out, the main lifting support shoe at the front end of the main frame is supported on the inner wall of the steel pipe, the main lifting support shoe at the rear end of the main frame is supported on the vehicle body, the step-by-step cylinder retracts, and the stepping drive device drives the sliding seat to enter the steel pipe.

[0023] S15. The main lifting support shoe of the main lifting mechanism retracts, the sliding support shoe on the sliding seat supports the inner wall of the steel pipe, the main lifting support shoe of the main lifting mechanism is suspended in the air, and the stepping drive device drives the main frame to move forward until it is completely inside the steel pipe.

[0024] S16. The main lifting support shoe of the main lifting mechanism extends out. The main lifting support shoe is supported by the inner wall of the steel pipe, which makes the sliding support shoe suspended in the air. The stepping drive device drives the sliding seat to move forward.

[0025] S17. The main lifting support shoe of the main lifting mechanism retracts, the sliding support shoe on the sliding seat supports the inner wall of the steel pipe, the main lifting support shoe of the main lifting mechanism is suspended in the air, and the stepping drive device drives the main frame to move forward inside the steel pipe.

[0026] S18. Repeat steps S16 and S17 to bring the main frame into the welding station.

[0027] S2, circumferential welding.

[0028] S21. The welding positioning mechanism, main machine positioning mechanism and walkway are all deployed. Adjust the support height of the main lifting mechanism and the extension of the support shoe translation cylinder to keep the welding system and the steel pipe coaxial.

[0029] S22. Extend the main unit positioning mechanism to fix the relative position of the main frame and the steel pipe;

[0030] S23. Extend the lifting frame to ensure that the relative position of the welding system and the circumferential weld is within the preset range;

[0031] S24. Unfold the walkway to make it compatible with the diameter of the steel pipe for easy observation and maintenance;

[0032] S25. The vision system of the welding system performs laser ranging to determine the position of the welding system and calculates the deviation between the position of the welding system and the preset position.

[0033] S26. Adjust the lifting frame, lateral drive device and longitudinal drive device of the welding positioning mechanism to move the welding system to the preset position;

[0034] S27. Perform pre-welding preparations;

[0035] S28. The welding system performs circumferential welding;

[0036] S29. Post-weld treatment;

[0037] S3, Welder shifts.

[0038] S31, the lifting frame, main unit positioning mechanism and walkway are all retracted, the main lifting support shoe of the main lifting mechanism is retracted, the sliding support shoe on the sliding seat supports the inner wall of the steel pipe, the main lifting support shoe of the main lifting mechanism is suspended in the air, and the stepping drive device drives the main frame to move forward inside the steel pipe.

[0039] S32, The main lifting support shoe of the main lifting mechanism extends out. The main lifting support shoe is supported by the inner wall of the steel pipe, which makes the sliding support shoe suspended in the air. The stepping drive device drives the sliding seat to move forward.

[0040] S33. Repeat steps S31 and S32 to move the main frame to the next welding station.

[0041] S34. Repeat step S2 to perform circumferential welding;

[0042] S4. After all welds are completed, the automatic welding equipment for horizontal butt joint circumferential seams of large-diameter steel pipes exits the pipe.

[0043] The present invention has the following beneficial effects:

[0044] The automatic welding equipment for horizontal butt welds of large-diameter steel pipes of this invention involves a transfer trolley transporting the automatic welding host to the pipe opening. A traveling mechanism then enters the pipe and drives the entire equipment forward or backward within the pipe, facilitating adjustment of the relative position between the automatic welding host and the circumferential weld. When the automatic welding host moves to the welding point, a host positioning mechanism positions the relative position between the host and the pipe. This positioning mechanism effectively adjusts the positioning of the welding system, unaffected by the host's positioning. The automatic welding host is an integral frame structure, with the welding system, welding positioning mechanism, traveling mechanism, and host positioning mechanism all mounted on the main frame. The step-by-step movement of the traveling mechanism is safe and reliable, eliminating the need for a reversing mechanism. It can adapt to situations where the axes of two steel pipe sections do not coincide, the straightness of the pipe exceeds the standard, or the roundness does not meet the standard, allowing the automatic welding host to smoothly complete the automatic welding work. It is suitable for welding the inner circumferential welds of horizontally positioned steel pipes with a diameter of 5-7 meters or steel pipes with a slight horizontal slope.

[0045] In addition to the objectives, features, and advantages described above, the present invention has other objectives, features, and advantages. The invention will now be described in further detail with reference to the figures. Attached Figure Description

[0046] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0047] Figure 1 This is a schematic diagram of the structure of an automatic welding equipment for horizontal butt joint circumferential seams of large-diameter steel pipes according to a preferred embodiment of the present invention;

[0048] Figure 2 This is a schematic diagram of the structure of the automatic welding equipment for horizontal butt joint circumferential seams of large-diameter steel pipes in the welding working state according to a preferred embodiment of the present invention;

[0049] Figure 3 This is a side view of an automatic welding device for horizontal butt joints of large-diameter steel pipes according to a preferred embodiment of the present invention;

[0050] Figure 4 This is a schematic diagram of the structure of the automatic welding host according to a preferred embodiment of the present invention;

[0051] Figure 5 This is a schematic diagram of the main frame structure of a preferred embodiment of the present invention;

[0052] Figure 6 This is a schematic diagram of the structure of the device platform according to a preferred embodiment of the present invention;

[0053] Figure 7 This is a schematic diagram of the main lifting mechanism according to a preferred embodiment of the present invention;

[0054] Figure 8 This is a schematic diagram of the sliding support mechanism according to a preferred embodiment of the present invention;

[0055] Figure 9 This is a schematic diagram of the host positioning mechanism according to a preferred embodiment of the present invention;

[0056] Figure 10 This is a schematic diagram of the walking mechanism according to a preferred embodiment of the present invention;

[0057] Figure 11 This is a schematic diagram of the welding system according to a preferred embodiment of the present invention;

[0058] Figure 12 This is a schematic diagram of the welding positioning mechanism according to a preferred embodiment of the present invention;

[0059] Figure 13 This is a schematic diagram of the arc welding mechanism according to a preferred embodiment of the present invention;

[0060] Figure 14 This is a schematic diagram of the flat welding mechanism according to a preferred embodiment of the present invention;

[0061] Figure 15 This is a schematic diagram of the lifting frame according to a preferred embodiment of the present invention;

[0062] Figure 16 This is a schematic diagram of the structure of the floating seat according to a preferred embodiment of the present invention;

[0063] Figure 17 This is a schematic diagram of the walkway structure according to a preferred embodiment of the present invention;

[0064] Figure 18 This is a schematic diagram of the structure of the transfer trolley according to a preferred embodiment of the present invention;

[0065] Figure 19 This is a schematic diagram of the structure of the automatic welding equipment for horizontal butt joint circumferential seams of large-diameter steel pipes in the preferred embodiment of the present invention in the traveling state.

[0066] Legend:

[0067] 100. Steel pipe; 1. Automatic welding host; 2. Transfer trolley; 21. Car body; 22. Trolley lifting mechanism; 3. Main frame; 31. Equipment platform; 32. Power supply; 33. Pump station; 34. Electrical control cabinet; 35. Lighting system; 4. Welding system; 41. Arc welding mechanism; 411. Arc track; 412. Arc rack; 413. Traveling trolley; 414. First welding robotic arm; 415. First welding torch; 42. Flat welding mechanism; 421. Second welding robotic arm; 422. Second welding torch; 5. Welding positioning mechanism; 51. Mounting seat; 52. Lifting frame; 521. Base plate; 522. Linear drive device; 523. Connecting seat; 524. Guide sleeve; 525. Guide rod; 53. Floating seat; 54. 55. Lateral drive device; 56. Longitudinal drive device; 6. Floating positioning plate; 6. Traveling mechanism; 61. Main lifting mechanism; 611. Main lifting slide; 612. Main lifting slide rail; 613. Main lifting cylinder; 614. Main lifting support shoe; 615. Support shoe slide; 616. Support shoe slide rail; 617. Support shoe translation cylinder; 618. First support shoe connecting rod; 62. Sliding support mechanism; 621. Slide rail; 622. Sliding seat; 623. Sliding support shoe; 624. Step-crossing cylinder; 625. Support pad; 626. Second support shoe connecting rod; 7. Main unit positioning mechanism; 71. Telescopic frame; 72. Telescopic rod; 73. Side support shoe; 74. Side support cylinder; 75. Direction adjustment cylinder; 8. Walkway; 81. First walkway; 82. Second walkway. Detailed Implementation

[0068] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, the present invention can be implemented in many different ways as defined and covered below.

[0069] Please also refer to Figures 1 to 19The automatic welding equipment for horizontal butt joint circumferential seams of large-diameter steel pipes in this embodiment uses the horizontal radial direction of the steel pipe as the X-axis, the axial direction as the Y-axis, and the vertical diameter direction as the Z-axis. The X-axis is used for left and right directions, the Y-axis for front and back directions, and the Z-axis for up and down directions. It includes an automatic welding host 1 and a transfer trolley 2 for transferring the automatic welding host 1. The automatic welding host 1 includes a main frame 3, a welding system 4, a welding positioning mechanism 5 for connecting the welding system 4 and the main frame 3, a traveling mechanism 6 for driving the main frame 3 to move along the axial direction of the steel pipe, and a host positioning mechanism 7 for fixing the relative position of the main frame 3 and the steel pipe. The traveling mechanism 6 includes a main lifting mechanism 61 for driving the main frame 3 to rise and fall, and a sliding support mechanism 62 arranged on the main frame 3 and movable along the axial direction of the steel pipe. The main lifting mechanism 61 and the sliding support mechanism 62 alternately support the main frame 3 to achieve step-by-step movement.

[0070] In this embodiment, the automatic welding equipment for horizontal butt welds of large-diameter steel pipes utilizes a transfer trolley 2 to transport the automatic welding host 1 to the pipe opening of the steel pipe 100. The traveling mechanism 6 then enters the steel pipe 100 and drives the entire equipment forward or backward within the pipe, facilitating adjustments to the relative position between the automatic welding host 1 and the circumferential weld seam. When the automatic welding host 1 moves to the welding work point, the host positioning mechanism 7 positions the relative position between the automatic welding host 1 and the steel pipe 100. The welding positioning mechanism 5 effectively adjusts the positioning of the welding system 4, unaffected by equipment limitations. The positioning of the main welding host 1 is affected; the automatic welding host 1 is an integral frame structure. The welding system 4, welding positioning mechanism 5, walking mechanism 6 and host positioning mechanism 7 are all installed on the main frame 3. The stepping movement of the walking mechanism 6 is safe and reliable, and the reversing operation can be completed without the need for a reversing mechanism. It can adapt to the situation where the axes of two steel pipes do not coincide, the straightness of the steel pipe exceeds the standard, or the roundness does not meet the standard, so that the automatic welding host 1 can complete the automatic welding work smoothly. It is suitable for welding the inner ring seam of steel pipes with a diameter of 5 to 7 meters in horizontal positions or steel pipes with a small slope in the horizontal direction.

[0071] Figure 5 , Figure 6 and Figure 7In this embodiment, the four main lifting mechanisms 61 are divided into two groups, respectively arranged at the front and rear ends of the main frame 3. The two main lifting mechanisms 61 in each group are symmetrically arranged on both sides of the main frame 3. Each main lifting mechanism 61 includes a main lifting slide 611 arranged on the main frame 3, a main lifting slide rail 612 slidably connected to the main lifting slide 611, a main lifting cylinder 613 for driving the main lifting slide rail 612 to slide vertically relative to the main lifting slide 611, and a main lifting support shoe 614 arranged on the main lifting slide rail 612 for abutting against the inner wall of the steel pipe. A support shoe slide 615 is arranged on the main lifting slide rail 612. The lifting support shoe 614 is equipped with a support shoe slide rail 616 that is slidably connected to the support shoe slide seat 615. The support shoe slide seat 615 and the main lifting support shoe 614 are connected by a support shoe translation cylinder 617. After the main lifting support shoe 614 presses against the inner wall of the steel pipe 100, the main lifting slide 612 drives the main frame 3 to rise and fall by extending and retracting, which can adjust the vertical height difference between the welding system 4 and the axis of the steel pipe 100. The extension and retraction of the support shoe translation cylinder 617 drives the main frame 3 to move left and right along the X-axis, which can adjust the horizontal distance between the welding system 4 and the axis of the steel pipe 100, thereby ensuring that the welding system 4 and the steel pipe remain coaxial during welding. Optionally, a soft pad is provided on the support surface of the main lifting support shoe 614 to ensure that the main lifting support shoe 614 fits against the pipe wall, reduce the pressure of the main lifting support shoe 614 on the inner wall of the steel pipe 100, and avoid damage to the paint surface of the inner wall of the steel pipe 100. Optionally, two adjacent main lifting support shoes 614 are connected by a first support shoe connecting rod 618, which can improve the support stability of the main lifting mechanism 61 and prevent the main lifting support shoes 614 from tilting.

[0072] Figure 5 , Figure 6 and Figure 8 In this embodiment, the sliding support mechanism 62 includes a slide rail 621 arranged along the axial direction of the steel pipe on the main frame 3, a sliding seat 622 slidably connected to the slide rail 621, a sliding support shoe 623 arranged on the sliding seat 622, and a stepping drive device for driving the sliding seat 622 to translate relative to the slide rail 621. When the automatic welding host 1 is supported by the main lifting support shoe 614, the sliding support shoe 623 is suspended, and the stepping drive device drives the sliding seat 622 to move forward. When the automatic welding host 1 is supported by the sliding support shoe 623, the lifting support shoe 614 is suspended, and the stepping drive device drives the main frame 3 to move forward, thereby realizing step-changing walking. Optionally, a soft pad is provided on the support surface of the sliding support shoe 623 to ensure that the sliding support shoe 623 fits against the pipe wall, reduce the pressure of the sliding support shoe 623 on the inner wall of the steel pipe 100, and avoid damage to the paint surface of the inner wall of the steel pipe 100. Optionally, two adjacent sliding support shoes 623 are connected by a second support shoe link 626, which can improve the support stability of the sliding support mechanism 62 and prevent the sliding support shoes 623 from tilting.

[0073] like Figure 5 , Figure 6 and Figure 8 As shown, in this embodiment, the sliding seat 622 is provided with a step-crossing cylinder 624 for driving the main frame 3 to rise and fall, and a support pad 625 is provided on the free end of the step-crossing cylinder 624. When the transfer trolley 2 carries the automatic welding host 1, the step-crossing cylinder 624 extends out and abuts against the body 21 of the transfer trolley 2. The main frame 3 is supported by the step-crossing cylinder 624, and the main lifting support shoe 614 of the main lifting mechanism 61 is suspended in the air. When the automatic welding host 1 enters and exits the steel pipe, the step-crossing cylinder 624 can compensate for the height difference between the steel pipe 100 and the transfer trolley 2, avoid interference between the main lifting mechanism 61 and the steel pipe, and ensure that the automatic welding host 1 can smoothly enter and exit the steel pipe 100.

[0074] like Figure 5 , Figure 6 and Figure 9 As shown, in this embodiment, two main positioning mechanisms 7 are arranged at the front and rear ends of the main frame 3. The main positioning mechanism 7 includes a telescopic frame 71 arranged on the main frame 3, a telescopic rod 72 slidably connected to the telescopic frame 71, a side support shoe 73 arranged on the free end of the telescopic rod 72, and a side support cylinder 74 for driving the telescopic rod 72 to drive the side support shoe 73 to abut against the inner wall of the steel pipe in the horizontal direction. The side support shoe 73 is adapted to the inner wall of the steel pipe 100. The main positioning mechanism 7 is a bidirectional telescopic structure. After the side support shoe 73 extends laterally and abuts against the inner wall of the steel pipe 100, the main frame 3 can be fixed to the inner wall of the steel pipe 100. Optionally, a soft pad is provided on the support surface of the side support shoe 73. On the one hand, this can ensure that the side support shoe 73 fits in close contact with the pipe wall, reduce the pressure of the side support shoe 73 on the inner wall of the steel pipe 100, and avoid damage to the paint surface of the inner wall of the steel pipe. On the other hand, it can increase the friction between the side support shoe 73 and the inner wall of the steel pipe 100, thereby ensuring the stability of the main frame 3.

[0075] like Figure 9 As shown, in this embodiment, the main unit positioning mechanism 7 further includes a directional hydraulic cylinder 75. One end of the directional hydraulic cylinder 75 is hinged to the telescopic frame 71, and the other end is hinged to the side support shoe 73. The side support shoe 73 is hinged to the free end of the telescopic rod 72. By extending and retracting the directional hydraulic cylinder 75, the angle between the side support shoe 73 and the horizontal plane is adjusted so that the side support shoe 73 fits against the inner wall of the steel pipe. This reduces the pressure of the side support shoe 73 on the inner wall of the steel pipe 100, avoids damage to the paint surface of the inner wall of the steel pipe 100, and ensures the stability of the main frame 3.

[0076] like Figures 10 to 16As shown, in this embodiment, the welding system 4 includes an arc welding mechanism 41 for welding the top and side arcs of the circumferential weld and a flat welding mechanism 42 for welding the bottom arc of the circumferential weld. The arc welding mechanism 41 includes an arc track 411, an arc rack 412 arranged on the arc track 411, a traveling trolley 413 arranged on the arc track 411 and adapted to the arc rack 412, and a first welding robotic arm 414 arranged on the traveling trolley 413. The first welding robotic arm 414 is equipped with a first welding torch 415, a first torch cleaner, a first vision system, and a first molten pool monitoring system. The arc welding mechanism 41 is suitable for welding arc welds of steel pipes. The trolley 413 travels along the arc-shaped track 411, driving the first welding robotic arm 414 to rotate along the arc-shaped track 411. A first vision system is mounted on the first welding robotic arm 414, using its extension and a preset program to measure its position. The position signal is fed back to the welding positioning mechanism 5, which calculates the positions of the first welding robotic arm 414 and the trolley 413 according to a preset algorithm. The welding positioning mechanism 5 then performs movement calculations. After the arc-shaped welding mechanism 41 and the flat welding mechanism 42 move to the designated positions, the circumferential weld of the steel pipe is performed. The molten pool monitoring system can monitor the automatic welding process remotely in real time, avoiding frequent movement of observers on the walkway. Optionally, the trolley 413 is driven by a servo motor. Optionally, the first welding robotic arm 414 is a six-axis robotic arm, which is flexible in operation, has a wide range of applications, and is suitable for a large range of steel pipe diameters.

[0077] like Figures 10 to 16As shown, in this embodiment, the welding positioning mechanism 5 includes a mounting base 51 mounted on the main frame 3, a lifting frame 52 mounted on the mounting base 51, a floating seat 53 mounted on the free end of the lifting frame 52, a transverse driving device 54 mounted on the floating seat 53, a longitudinal driving device 55 mounted on the transverse driving device 54, and a floating positioning plate 56 mounted on the longitudinal driving device 55. The lifting frame 52, the transverse driving device 54, and the longitudinal driving device 55 are arranged perpendicular to each other, and the transverse driving device 54 or the longitudinal driving device 55 is arranged along the axial direction of the steel pipe; Each arc-shaped welding mechanism 41 is respectively arranged on a corresponding floating positioning plate 56. The flat welding mechanism 42 includes a second welding robotic arm 421 arranged on a corresponding floating positioning plate 56. The second welding robotic arm 421 is equipped with a second welding torch 422, a second torch cleaner, a second vision system, and a second molten pool monitoring system. Taking the arc-shaped welding mechanism 41 at the top as an example, on the one hand, when changing walking distances, the arc-shaped welding mechanism 41 can be retracted towards the main frame 3, reducing the maximum external dimensions of the entire equipment and facilitating movement; on the other hand, the lifting frame 52 can provide arc-shaped welding mechanisms. The positioning adjustment of the arc welding mechanism 41 in the Z-axis direction; the floating positioning disk 56 provides positioning adjustment of the arc welding mechanism 41 in the X and Y axes; the first vision system on the first welding robot arm 414 uses laser positioning to measure the position data, the controller calculates the deviation value between the position of the arc track 411 and the preset position, and the welding positioning mechanism 5 adjusts the position of the arc track 411 according to the deviation value to make it reach the preset welding position; the arc welding mechanisms 41 on both sides perform the same positioning; for the flat welding mechanism 42, the second vision system on the second welding robot arm 421 uses laser positioning to measure the position data, the controller calculates the deviation value between the position of the second welding robot arm 421 and the preset position, and the welding positioning mechanism 5 quickly adjusts the position of the second welding robot arm 421 according to the deviation value to make it reach the preset welding position; the three sets of arc welding mechanisms 41 and one set of flat welding mechanisms 42 are controlled independently by their respective control systems. The entire welding system 4 can realize the welding of all welds of the steel pipe circumferential seam and realize automated welding. The robot arm moves in circles on multiple arc tracks, which can reasonably allocate welding efficiency. The welding mechanism will not be idle, and the working efficiency is high. Optionally, the lifting frame 52 includes a base plate 521, a connecting seat 523, and a linear drive device 522. The linear drive device 522 is mounted on the base plate 521. The base plate 521 is connected to the mounting base 51 via a guide sleeve 524. A guide rod 525 is slidably embedded in the guide sleeve 524. The connecting seat 523 is mounted on the free end of the linear drive device 522 and connected to the guide rod 525. The linear drive device 522 drives the connecting seat 523 to rise and fall relative to the mounting base 51. The guide rod 525 improves the stability of the connecting seat 523, preventing vibration and displacement, thereby ensuring the stability of the welding system 4. Optionally, the linear drive device 522, the transverse drive device 54, and the longitudinal drive device 55 are each driven by a servo motor.

[0078] like Figure 4 and Figure 17 As shown, in this embodiment, the main frame 3 is provided with a walkway 8 for welding observation and / or maintenance. The walkway 8 includes a first walkway 81 that can be raised and lowered vertically and a second walkway 82 that can be extended and retracted horizontally. The two second walkways 82 are arranged on both sides of the first walkway 81, corresponding to the three arc-shaped welding mechanisms 41 respectively. Optionally, the two walkways 8 are arranged on the front and rear sides of the welding system 4 respectively. Optionally, the walkway 8 is provided with guardrails.

[0079] like Figure 18 As shown, in this embodiment, the transfer trolley 2 includes a car body 21 and a trolley lifting mechanism 22 for driving the car body 21 to rise and fall. The transfer trolley 2 can realize the transportation and turning along the track in the tunnel, and can transfer the automatic welding host 1 to the predetermined work location. At the same time, the transfer trolley 2 has a lifting function. After transporting the automatic welding host 1 to the position of entering the steel pipe 100, the support height can be adjusted to assist the automatic welding host 1 in entering the steel pipe.

[0080] like Figure 5 and Figure 6 As shown, in this embodiment, an equipment platform 31 is mounted on the main frame 3. The equipment platform 31 is equipped with a power supply 32 for providing electricity, a pump station 33 for providing hydraulic oil, and an electrical control cabinet 34. Optionally, a lighting system 35 is mounted on the main frame 3 to facilitate image acquisition by the vision system and for personnel to observe and perform maintenance. Optionally, a wire feeder and a welding wire spool are mounted on the equipment platform 31.

[0081] An automatic welding method for horizontal butt joints of large-diameter steel pipes includes the following steps:

[0082] S1, Equipment Inlet Pipe

[0083] S11, such as Figure 19 As shown, the welding system 4, welding positioning mechanism 5, main machine positioning mechanism 7 and walkway 8 are all retracted to reduce the maximum external profile of the automatic welding equipment for horizontal butt joint circumferential seam of large diameter steel pipes. The step-over cylinder 624 of the sliding support mechanism 62 extends and abuts against the car body 21 of the transfer trolley 2. The main frame 3 is supported by the step-over cylinder 624, and the main lifting support shoe 614 of the main lifting mechanism 61 is suspended in the air.

[0084] S12, the transfer trolley 2 transports the automatic welding equipment for the horizontal butt joint of the large-diameter steel pipe to the front end of the steel pipe. The trolley body 21 enters the lower end of the steel pipe cantilever and extends the trolley lifting mechanism 22 so that the trolley body 21 supports the cantilever section of the steel pipe.

[0085] S13, the stepping drive device of the sliding support mechanism 62 drives one end of the main frame 3 into the steel pipe;

[0086] S14, the main lifting support shoe 614 of the main lifting mechanism 61 extends, the main lifting support shoe 614 at the front end of the main frame 3 is supported on the inner wall of the steel pipe, the main lifting support shoe 614 at the rear end of the main frame 3 is supported on the vehicle body 21, the step cylinder 624 retracts, and the stepping drive device drives the sliding seat 622 to enter the steel pipe.

[0087] S15, the main lifting support shoe 614 of the main lifting mechanism 61 retracts, the sliding support shoe 623 on the sliding seat 622 supports the inner wall of the steel pipe, the main lifting support shoe 614 of the main lifting mechanism 61 is suspended, and the stepping drive device drives the main frame 3 to move forward until it is fully inside the steel pipe.

[0088] S16. The main lifting support shoe 614 of the main lifting mechanism 61 extends out. The main lifting support shoe 614 is supported by the inner wall of the steel pipe, which makes the sliding support shoe 623 suspended in the air. The stepping drive device drives the sliding seat 622 to move forward.

[0089] S17, the main lifting support shoe 614 of the main lifting mechanism 61 retracts, the sliding support shoe 623 on the sliding seat 622 supports the inner wall of the steel pipe, the main lifting support shoe 614 of the main lifting mechanism 61 is suspended, and the stepping drive device drives the main frame 3 to move forward inside the steel pipe.

[0090] S18. Repeat steps S16 and S17 to bring the main frame 3 into the welding station.

[0091] In this embodiment, step S15 specifically includes:

[0092] The main lifting support shoe 614 of the main lifting mechanism 61 retracts, the sliding support shoe 623 at the front end of the sliding seat 622 is supported on the inner wall of the steel pipe, the sliding support shoe 623 at the front end of the sliding seat 622 is on the vehicle body 21, the main lifting support shoe 614 of the main lifting mechanism 61 is suspended in the air, and the stepping drive device drives the main frame 3 to move forward into the steel pipe.

[0093] The main lifting support shoe 614 of the main lifting mechanism 61 extends out and is supported by the inner wall of the steel pipe. The sliding support shoe 623 is suspended in the air. The stepping drive device drives the sliding seat 622 to move forward and completely enter the steel pipe 100.

[0094] The main lifting support shoe 614 of the main lifting mechanism 61 retracts, and the sliding support shoe 623 on the sliding seat 622 is supported on the inner wall of the steel pipe. The main lifting support shoe 614 of the main lifting mechanism 61 is suspended in the air, and the stepping drive device drives the main frame 3 to move forward until it is fully inserted into the steel pipe 100.

[0095] S2, circumferential welding.

[0096] S21, such as Figure 2As shown, the welding positioning mechanism 5, the main machine positioning mechanism 7 and the walkway 8 are all deployed. The support height of the main lifting mechanism 61 and the extension amount of the support shoe translation cylinder 617 are adjusted to keep the welding system 4 and the steel pipe coaxial.

[0097] S22. Extend the main unit positioning mechanism 7 to fix the relative position of the main frame 3 and the steel pipe;

[0098] S23. Extend the lifting frame 52 to ensure that the relative position of the welding system 4 and the circumferential weld is within the preset range;

[0099] S24. Unfold the walkway 8 to make it compatible with the diameter of the steel pipe, so as to facilitate observation and maintenance;

[0100] S25. The vision system of welding system 4 performs laser ranging to determine the position of welding system 4 and calculates the deviation value between the position of welding system 4 and the preset position.

[0101] S26. Adjust the lifting frame 52, the transverse drive device 54 and the longitudinal drive device 55 of the welding positioning mechanism 5 to move the welding system 4 to the preset position.

[0102] S27. Perform pre-welding preparations, including grinding and preheating;

[0103] S28, Welding System 4 performs circumferential welding, circumferential root pass, automated welding by robotic arm, and root cleaning;

[0104] S29. Post-weld treatment.

[0105] In this embodiment, in step S28, the automated welding by the robotic arm is either segmented welding in the same layer and same pass or simultaneous welding of multiple weld seams.

[0106] S3, Welder shifts.

[0107] S31, lifting frame 52, main unit positioning mechanism 7 and walkway 8 are all retracted, the main lifting support shoe 614 of the main lifting mechanism 61 is retracted, the sliding support shoe 623 on the sliding seat 622 supports the inner wall of the steel pipe, the main lifting support shoe 614 of the main lifting mechanism 61 is suspended, and the stepping drive device drives the main frame 3 to move forward inside the steel pipe.

[0108] S32, the main lifting support shoe 614 of the main lifting mechanism 61 extends out. The main lifting support shoe 614 is supported by the inner wall of the steel pipe, which makes the sliding support shoe 623 suspended in the air. The stepping drive device drives the sliding seat 622 to move forward.

[0109] S33. Repeat steps S31 and S32 to move the main frame 3 to the next welding station.

[0110] S34. Repeat step S2 to perform circumferential welding.

[0111] S4. After all welds are completed, the automatic welding equipment for horizontal butt joint circumferential seams of large-diameter steel pipes exits the pipe.

[0112] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. An automatic welding device for horizontal butt joints of large-diameter steel pipes, characterized in that, The system includes an automatic welding host (1) and a transfer trolley (2) for transferring the automatic welding host (1). The automatic welding host (1) includes a main frame (3), a welding system (4), a welding positioning mechanism (5) for connecting the welding system (4) and the main frame (3), a traveling mechanism (6) for driving the main frame (3) to move along the steel pipe axis, and a host positioning mechanism (7) for fixing the relative position of the main frame (3) and the steel pipe. The traveling mechanism (6) enters the steel pipe and drives the entire equipment to move forward or backward within the steel pipe. The traveling mechanism (6) includes a main lifting mechanism (61) for lifting the main frame (3) and a sliding support mechanism (62) arranged on the main frame (3) and movable along the steel pipe axis. The main lifting mechanism (61) and the sliding support mechanism (62) alternately support the main frame (3) to achieve step-by-step movement. The main lifting mechanism (61) includes a main lifting slide (611) mounted on the main frame (3), a main lifting slide rail (612) slidably connected to the main lifting slide (611), a main lifting cylinder (613) for driving the main lifting slide rail (612) to slide vertically relative to the main lifting slide (611), and a main lifting support shoe (614) mounted on the main lifting slide rail (612) for abutting against the inner wall of the steel pipe. The main lifting slide rail (612) is provided with a support shoe slide (615), and the main lifting support shoe (614) is provided with a support shoe slide rail (616) slidably connected to the support shoe slide (615). The support shoe slide (615) and the main lifting support shoe (614) are connected by a support shoe translation cylinder (617). The sliding support mechanism (62) includes a slide rail (621) arranged along the axial direction of the steel pipe on the main frame (3), a sliding seat (622) slidably connected to the slide rail (621), a sliding support shoe (623) arranged on the sliding seat (622), and a stepping drive device for driving the sliding seat (622) to translate relative to the slide rail (621). When the automatic welding host (1) is supported by the main lifting support shoe (614), the sliding support shoe (623) is suspended, and the stepping drive device drives the sliding seat (622) to move forward; when the automatic welding host (1) is supported by the sliding support shoe (623), the lifting support shoe (614) is suspended, and the stepping drive device drives the main frame (3) to move forward, thereby realizing step-changing walking. The sliding seat (622) is provided with a step-through cylinder (624) for driving the main frame (3) to rise and fall, and a support pad (625) is provided on the free end of the step-through cylinder (624).

2. The automatic welding equipment for horizontal butt joints of large-diameter steel pipes according to claim 1, characterized in that, The main positioning mechanism (7) includes a telescopic frame (71) mounted on the main frame (3), a telescopic rod (72) slidably connected to the telescopic frame (71), a side support shoe (73) mounted on the free end of the telescopic rod (72), and a side support cylinder (74) for driving the telescopic rod (72) to drive the side support shoe (73) to abut against the inner wall of the steel pipe in the horizontal direction.

3. The automatic welding equipment for horizontal butt joints of large-diameter steel pipes according to claim 2, characterized in that, The main positioning mechanism (7) further includes a directional cylinder (75). One end of the directional cylinder (75) is hinged to the telescopic frame (71), and the other end is hinged to the side support shoe (73). The side support shoe (73) is hinged to the free end of the telescopic rod (72). The angle between the side support shoe (73) and the horizontal plane is adjusted by the extension and retraction of the directional cylinder (75) so that the side support shoe (73) fits against the inner wall of the steel pipe.

4. The automatic welding equipment for horizontal butt joints of large-diameter steel pipes according to claim 1, characterized in that, The welding system (4) includes an arc welding mechanism (41) for welding the top arc and the two side arcs of the circumferential seam and a flat welding mechanism (42) for welding the bottom arc of the circumferential seam. The arc welding mechanism (41) includes an arc track (411), an arc rack (412) arranged on the arc track (411), a traveling trolley (413) arranged on the arc track (411) and adapted to the arc rack (412), and a first welding robot arm (414) arranged on the traveling trolley (413). The first welding robot arm (414) is equipped with a first welding torch (415), a first torch cleaner, a first vision system, and a first molten pool monitoring system.

5. The automatic welding equipment for horizontal butt joints of large-diameter steel pipes according to claim 4, characterized in that, The welding positioning mechanism (5) includes a mounting base (51) on the main frame (3), a lifting frame (52) on the mounting base (51), a floating seat (53) on the free end of the lifting frame (52), a lateral drive device (54) on the floating seat (53), a longitudinal drive device (55) on the lateral drive device (54), and a floating positioning plate (56) on the longitudinal drive device (55). The longitudinal drive devices (55) are arranged perpendicular to each other, and the transverse drive device (54) or the longitudinal drive device (55) is arranged along the axial direction of the steel pipe; the three arc welding mechanisms (41) are respectively arranged on the corresponding floating positioning disks (56), and the flat welding mechanism (42) includes a second welding robot arm (421) arranged on the corresponding floating positioning disks (56). The second welding robot arm (421) is equipped with a second welding torch (422), a second torch cleaner, a second vision system, and a second molten pool monitoring system.

6. The automatic welding equipment for horizontal butt joints of large-diameter steel pipes according to claim 5, characterized in that, The main frame (3) is provided with a walkway (8) for observation and / or maintenance. The walkway (8) includes a first walkway (81) that can be raised and lowered in the vertical direction and a second walkway (82) that can be extended and retracted in the horizontal direction. The two second walkways (82) are arranged on both sides of the first walkway (81) and correspond to the three arc welding mechanisms (41) respectively.

7. The automatic welding equipment for horizontal butt joints of large-diameter steel pipes according to claim 6, characterized in that, The transfer trolley (2) includes a car body (21) and a trolley lifting mechanism (22) for driving the car body (21) to rise and fall.

8. The automatic welding equipment for horizontal butt joints of large-diameter steel pipes according to claim 1, characterized in that, The main frame (3) is provided with an equipment platform (31), and the equipment platform (31) is provided with a power supply (32) for providing electricity, a pump station (33) for providing hydraulic oil and an electrical control cabinet (34).

9. An automatic welding method for horizontal butt joints of large-diameter steel pipes, characterized in that, The automatic welding equipment for horizontal butt joints of large-diameter steel pipes as described in claim 7 includes the following steps: S1, Equipment inlet pipe; S11, welding system (4), welding positioning mechanism (5), main machine positioning mechanism (7) and walkway (8) are all contracted to reduce the maximum outline of the automatic welding equipment for horizontal butt joint circumferential seam of large diameter steel pipe. The step-over cylinder (624) of the sliding support mechanism (62) extends and abuts against the car body (21) of the transfer trolley (2). The main frame (3) is supported by the step-over cylinder (624). The main lifting support shoe (614) of the main lifting mechanism (61) is suspended in the air. S12, the transfer trolley (2) transports the automatic welding equipment for the horizontal butt joint of the large-diameter steel pipe to the front end of the steel pipe. The trolley body (21) enters the lower end of the steel pipe cantilever and extends the trolley lifting mechanism (22) so that the trolley body (21) supports the cantilever section of the steel pipe. S13, The stepping drive device of the sliding support mechanism (62) drives one end of the main frame (3) into the steel pipe; S14, the main lifting support shoe (614) of the main lifting mechanism (61) extends out, the main lifting support shoe (614) at the front end of the main frame (3) is supported on the inner wall of the steel pipe, the main lifting support shoe (614) at the rear end of the main frame (3) is supported on the vehicle body (21), the step cylinder (624) retracts, and the stepping drive device drives the sliding seat (622) to enter the steel pipe; S15, the main lifting support shoe (614) of the main lifting mechanism (61) retracts, the sliding support shoe (623) on the sliding seat (622) supports the inner wall of the steel pipe, the main lifting support shoe (614) of the main lifting mechanism (61) is suspended, and the stepping drive device drives the main frame (3) to move forward until it is fully inside the steel pipe. S16, The main lifting support shoe (614) of the main lifting mechanism (61) extends out. The main lifting support shoe (614) is supported by the inner wall of the steel pipe, and the sliding support shoe (623) is suspended in the air. The stepping drive device drives the sliding seat (622) to move forward. S17, the main lifting support shoe (614) of the main lifting mechanism (61) retracts, the sliding support shoe (623) on the sliding seat (622) supports the inner wall of the steel pipe, the main lifting support shoe (614) of the main lifting mechanism (61) is suspended, and the stepping drive device drives the main frame (3) to move forward in the steel pipe; S18. Repeat steps S16 and S17 to bring the main frame (3) into the welding station. S2, circumferential welding; S21. The welding positioning mechanism (5), the main machine positioning mechanism (7) and the walkway (8) are all deployed. The support height of the main lifting mechanism (61) and the extension of the support shoe translation cylinder (617) are adjusted so that the welding system (4) and the steel pipe remain coaxial. S22, Extend the main unit positioning mechanism (7) to fix the relative position of the main frame (3) and the steel pipe; S23. Extend the lifting frame (52) to make the relative position of the welding system (4) and the circumferential weld within the preset range; S24. Unfold the walkway (8) to make it compatible with the diameter of the steel pipe for easy observation and maintenance; S25. The vision system of the welding system (4) performs laser ranging to determine the position of the welding system (4) and calculates the deviation value between the position of the welding system (4) and the preset position. S26. Adjust the lifting frame (52), the transverse drive device (54) and the longitudinal drive device (55) of the welding positioning mechanism (5) to move the welding system (4) to the preset position; S27. Perform pre-welding preparations; S28. Welding system (4) performs circumferential welding; S29. Post-weld treatment; S3, Welding worker shifts; S31, the lifting frame (52), the main positioning mechanism (7) and the walkway (8) are all retracted, the main lifting support shoe (614) of the main lifting mechanism (61) is retracted, the sliding support shoe (623) on the sliding seat (622) supports the inner wall of the steel pipe, the main lifting support shoe (614) of the main lifting mechanism (61) is suspended, and the stepping drive device drives the main frame (3) to move forward in the steel pipe; S32, the main lifting support shoe (614) of the main lifting mechanism (61) extends out, the main lifting support shoe (614) is supported by the inner wall of the steel pipe, and the sliding support shoe (623) is suspended in the air, and the stepping drive device drives the sliding seat (622) to move forward; S33. Repeat steps S31 and S32 to move the main frame (3) to the next welding station; S34. Repeat step S2 to perform circumferential welding; S4. After all welds are completed, the automatic welding equipment for horizontal butt joint circumferential seams of large-diameter steel pipes exits the pipe.

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