Offshore wind turbine tower welding device

Abstract

The present invention discloses an offshore wind turbine tower welding device, comprising an external tower welding device and an internal tower welding device. The internal tower welding device comprises a self-propelled vehicle and a welding robot, which is fixed to the self-propelled vehicle. The self-propelled vehicle comprises a vehicle body, a driving wheel, and a plurality of follower wheels. The driving wheel is disposed in the middle of the lower side of the vehicle body via a slewing mechanism, and the plurality of follower wheels are distributed around the lower side of the vehicle body. The present invention uses the external tower welding device and the internal tower welding device to simultaneously weld the inner and outer sides of the tower, thereby shortening the tower welding time and improving the tower welding efficiency.

Description

Technical Field

[0001] The invention relates to a welding device, in particular to an offshore wind turbine tower welding device, belonging to the technical field of wind power. Background Art

[0002] Offshore wind turbine monopile foundations are important components of offshore wind power. As the capacity of current offshore wind power projects increases, the weight of the latest ultra-large offshore wind turbine monopiles has reached over 3,000 tons. Compared with current conventional towers, the diameter and thickness of ultra-large wind turbine monopiles have increased significantly. Currently, for tower welding, welding is mainly performed on the outside of the tower. When the diameter and thickness of the tower increase significantly, the external welding method alone increases the welding time, and the welding efficiency of ultra-large sleeves is relatively low. Therefore, it is necessary to design a new tower welding device that can weld from both the outside and inside of the tower at the same time, shortening the tower welding time and improving the sleeve welding efficiency. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide an offshore wind turbine tower welding device to improve the welding efficiency of super-large wind turbine towers.

[0004] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0005] An offshore wind turbine tower welding device includes an external tower welding device and an internal tower welding device. The internal tower welding device includes a self-propelled vehicle body and a welding robot. The welding robot is fixed on the self-propelled vehicle body. The self-propelled vehicle body includes a vehicle body, a driving wheel and a plurality of follower wheels. The driving wheel is arranged in the middle of the lower side of the vehicle body through a rotating mechanism, and the plurality of follower wheels are distributed around the lower side of the vehicle body.

[0006] The transmission gear of the present invention is connected with the transmission gear of the first gear to the transmission gear of the second end face wall, and the transmission gear of the second gear is connected with the transmission gear of the second gear to the transmission gear of the second end face.

[0007] The gear train is connected to the first gear and the second gear is connected to the first gear via a gear rotation, and the gear train is connected to the first gear via a gear rotation, so that the gear train is connected to the first gear and the second gear is connected to the first gear via a gear rotation.

[0008] Furthermore, the pendulum is a fan-shaped pendulum.

[0009] Furthermore, the driving wheel includes an outer wheel body and a hub motor. The outer wheel body is fixed on the outer rotor of the hub motor and driven by the hub motor. The internal stator of the hub motor is fixed on the motor support. The motor support is rotated by a rotating shaft mechanism and is set in the middle of the lower side of the vehicle body.

[0010] Furthermore, the rotating shaft mechanism includes a rotating shaft sleeve, a rotating shaft slide, a second electric push rod and a fixed sleeve. The rotating shaft mounting plate is fixed to the upper end of the rotating shaft sleeve, and the rotating shaft sleeve is rotatably set in the middle position of the vehicle body through the rotating shaft mounting plate. The upper end of the rotating shaft slide is slidably set in the cylinder body of the lower end of the rotating shaft sleeve and can slide up and down along the inner wall of the cylinder body of the rotating shaft sleeve. The lower end of the rotating shaft slide is fixed to the motor support, and the fixed sleeve is arranged on the outside of the rotating shaft slide and is fixedly connected to the rotating shaft slide. The second electric push rod is vertically fixed to the side of the rotating shaft sleeve and the push rod end of the second electric push rod is hinged to the fixed sleeve to drive the rotating shaft slide to rise and fall vertically in the rotating shaft sleeve.

[0011] Furthermore, a plurality of electromagnet sheets are provided on the circumferential surface of the outer wheel body, each of which is a V-shaped electromagnet sheet. The plurality of electromagnet sheets are arranged on the circumferential surface of the outer wheel body in the same clockwise order and adjacent electromagnet sheets are separated by insulating non-magnetic materials. The electromagnet sheet located at the lower end of the outer wheel body is powered by an electromagnet power supply mechanism.

[0012] Furthermore, the electromagnet power supply mechanism includes a circular power supply slot mounting bracket, multiple power supply slots and power supply terminals. The number of power supply slots is equal to the number of electromagnet sheets. The multiple power supply slots are fixedly arranged in the circular power supply slot mounting bracket and are evenly spaced along the circumference of the circular power supply slot mounting bracket. Each power supply slot is connected to the corresponding electromagnet sheet through a wire. One end of the power supply terminal is fixed on the internal stator of the hub motor and connected to the power supply, and the other end of the power supply terminal is slidably arranged in the power supply slot.

[0013] Furthermore, the power supply slot includes a first arc-shaped conductor piece, a second arc-shaped conductor piece, an insulating bolt, an insulating nut and an insulating gasket. One end of the first arc-shaped conductor piece and the second arc-shaped conductor piece is provided with mounting parts parallel to each other, and the insulating gasket is provided between the mounting parts of the first arc-shaped conductor piece and the second arc-shaped conductor piece. Screw holes are provided on the mounting parts of the first arc-shaped conductor piece and the second arc-shaped conductor piece and the insulating gasket. The insulating bolt passes through the screw holes of the mounting part of the first arc-shaped conductor piece, the insulating gasket and the second arc-shaped conductor piece and is then locked and fixed by the insulating nut. The power supply terminal includes a spherical end and a cylindrical terminal body. The contact parts of the two sides of the spherical end with the first arc-shaped conductor piece and the second arc-shaped conductor piece are conductors. The conductors on both sides of the spherical end are separated by insulating material. The spherical end is fixed to the end of the cylindrical terminal body. The other end of the first arc-shaped conductor piece and the second arc-shaped conductor piece forms an opening smaller than the diameter of the spherical end.

[0014] Furthermore, the follower wheel includes a universal wheel and a follower wheel bracket, the universal wheel is arranged at the lower end of the follower wheel bracket, the upper end of the follower wheel bracket is fixed at the four corners of the lower side of the vehicle body, and the follower wheel bracket is bent and protruded outward.

[0015] Compared with the prior art, the present invention has the following advantages and effects:

[0016] 1. The present invention provides an offshore wind turbine tower welding device, which simultaneously welds the inner and outer sides of the tower through an external tower welding device and an internal tower welding device, thereby shortening the tower welding time and improving the tower welding efficiency;

[0017] 2. The present invention uses driving wheels to drive the self-propelled vehicle body for movement and steering. Multiple follower wheels support the vehicle body and move with the driving wheels. The driving wheels can be raised and lowered to accommodate towers of different diameters.

[0018] 3. The present invention uses a pendulum to detect whether the self-propelled vehicle body is deviated. When deviated, the pendulum swings to drive the third gear to rotate, and finally drives the driving wheel to adjust the steering so that the self-propelled vehicle body keeps moving in a straight line.

[0019] 4. The driving wheel of the present invention adopts an electromagnet sheet to be adsorbed on the inner wall of the tower to prevent the wheel body and the inner wall of the sleeve from slipping, thereby ensuring the synchronization of the welding robots on both sides. The driving wheel is designed with a unique power supply structure. Only the electromagnet sheet at the bottom is energized for adsorption, which simplifies control and reduces energy consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic diagram of the offshore wind turbine tower welding device of the present invention.

[0021] Figure 2 Schematic diagram of the internal tower welding device of the present invention.

[0022] Figure 3 Schematic diagram of a self-propelled vehicle body of the present invention.

[0023] Figure 4 It is a schematic diagram of the rotary mechanism of the present invention.

[0024] Figure 5 It is a right side view of the third gear drive mechanism of the present invention.

[0025] Figure 6 1 is a top view of the third gear drive mechanism of the present invention.

[0026] Figure 7 It is a schematic diagram of the driving wheel of the present invention.

[0027] Figure 8 It is a side view of the driving wheel of the present invention.

[0028] Figure 9 Schematic diagram of the power supply terminal of the present invention. DETAILED DESCRIPTION

[0029] In order to elaborate on the technical solutions adopted by the present invention to achieve the predetermined technical purpose, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments, and the technical means or technical features in the embodiments of the present invention can be replaced without creative work. The present invention will be described in detail below with reference to the drawings and in conjunction with the embodiments.

[0030] like Figure 1 As shown, an offshore wind turbine tower welding device of the present invention includes an external tower welding device 1 and an internal tower welding device 2. The external tower welding device and the internal tower welding device are used to weld the inner and outer sides of the tower at the same time, thereby shortening the tower welding time and improving the tower welding efficiency.

[0031] like Figure 2As shown, the internal tower welding device 2 includes a self-propelled vehicle body 3 and a welding robot 4 , and the welding robot 4 is fixed on the self-propelled vehicle body 3 .

[0032] like Figure 3 As shown, the self-propelled vehicle 3 includes a body 5, a driving wheel 6, and several follower wheels 7. The driving wheel 6 is arranged in the middle of the lower side of the body 5 through a slewing mechanism, and the several follower wheels 7 are distributed around the lower side of the body 5. The driving wheel 6 drives the self-propelled vehicle 3 and controls the steering of the self-propelled vehicle 3, while the several follower wheels 7 follow the driving wheel 6.

[0033] like Figure 4 As shown, the rotary mechanism includes a shaft mechanism, a shaft mounting plate 8, a limiting ring 9, a first gear 10, a first electric push rod 11, a second gear 12, a gear drive motor 13, a third gear 14 and a third gear drive mechanism. The shaft mounting plate 8 is fixed to the upper end of the shaft mechanism. The limiting ring 9 is sleeved on the outside of the shaft mechanism and is fixedly connected to the shaft mechanism. The first gear 10 is sleeved on the outside of the shaft mechanism through a spline and can slide up and down along the outer wall of the shaft mechanism between the shaft mounting plate 8 and the limiting ring 9. The presence of the spline structure prevents the first gear 10 from rotating relative to the shaft mechanism. The lower side of the first gear 10 is connected to the first electric push rod 11 and is driven by the first electric push rod 11. The first electric push rod 11 is vertically fixed to the outside of the shaft mechanism. The first electric push rod 11 drives the first gear 10 to slide up and down along the outer wall of the shaft mechanism between the shaft mounting plate 8 and the limiting ring 9. When the lower side of the first gear 10 abuts against the upper side of the limit ring 9, that is, when the first gear 10 drops to the lowest position, the first gear 10 meshes with the second gear 12, and the second gear 12 is connected to the gear drive motor 13 and driven by the gear drive motor 13. In this state, the gear drive motor 13 drives the second gear 12 to rotate, and the second gear 12 drives the first gear 10 to rotate, thereby controlling the steering of the driving wheel 6. When the upper side of the first gear 10 abuts against the lower side of the rotating shaft and turntable 8, that is, when the first gear 10 rises to the highest position, the first gear 10 meshes with the third gear 14, and the third gear 14 is rotatably mounted on the vehicle body and driven by the third gear drive mechanism. In this state, the third gear drive mechanism drives the third gear 14 to rotate, and the third gear 14 drives the first gear 10 to rotate, thereby controlling the steering of the driving wheel 6.

[0034] like Figure 4 、 Figure 5 and Figure 6As shown, the third gear drive mechanism includes a pendulum 15, a swing arm 16, a vertical slide rod 17, a horizontal slide rod 18 and a horizontal slide rod bracket 19. The pendulum 15 is hinged on the lower side of the vehicle body 5, and the lower end of the swing arm 16 is fixedly connected to the upper end of the pendulum 15. Since the pendulum 15 is hinged on the vehicle body 5, when the self-propelled vehicle body 3 moves axially along the sleeve to the weld position, since the cross-section of the tower is circular, when the self-propelled vehicle body 3 deviates in direction, the self-propelled vehicle body 3 is not located at the lowest end of the circular tower, and the self-propelled vehicle body 3 will be deflected. At this time, the pendulum 15 will deflect toward the lowest end of the tower under the action of gravity, and the swing arm 16 at the upper end will swing to the other side. The upper end of the swing arm 16 is hinged to the lower end of the vertical slide rod 17, the horizontal slide rod 18 is horizontally arranged along the radial direction of the first gear 10 and the two ends of the horizontal slide rod 18 are fixed on the horizontal slide rod bracket 19, the upper end of the vertical slide rod 17 is sleeved on the horizontal slide rod 18 and can slide back and forth along the horizontal slide rod 18, the third gear 14 is provided with a slide rod guide groove 20, the slide rod guide groove 20 is inclined to the radial direction of the third gear 14, the vertical slide rod 17 is slidably arranged in the slide rod guide groove 20, when the swing arm 16 is horizontally arranged along the radial direction of the first gear 10 and the two ends of the horizontal slide rod 18 are fixed on the horizontal slide rod bracket 19, the upper end of the vertical slide rod 17 is sleeved on the horizontal slide rod 18 and can slide back and forth along the horizontal slide rod 18, the third gear 14 is provided with a slide rod guide groove 20, the slide rod guide groove 20 is inclined to the radial direction of the third gear 14, the vertical slide rod 17 is slidably arranged in the slide rod guide groove 20, When the hammer 15 swings to the left, the self-propelled vehicle 3 deflects to the right. The swing arm 16 drives the vertical slide 17 to slide radially along the third gear 14 toward the center of the third gear 14, thereby driving the third gear 14 to rotate clockwise through the slide guide groove 20. When the first gear 10 engages with the third gear 14, the first gear 10 is driven by the third gear 14 to rotate counterclockwise, thereby driving the driving wheel 6 to the left, returning the self-propelled vehicle 3 to the center of the lowest end of the tower. When the pendulum 15 swings to the right, the self-propelled vehicle 3 deflects to the left. The swing arm 16 drives the vertical slide 17 to slide radially along the third gear 14 toward the edge of the third gear 14, thereby driving the third gear 14 to rotate counterclockwise through the slide guide groove 20. When the first gear 10 engages with the third gear 14, the first gear 10 is driven by the third gear 14 to rotate clockwise, thereby driving the driving wheel 6 to the right, returning the self-propelled vehicle 3 to the center of the lowest end of the tower.

[0035] The pendulum 15 is a fan-shaped pendulum, and the structure of the fan-shaped pendulum is more sensitive to the offset position of the self-propelled vehicle body 3 in the circular tower.

[0036] like Figure 4 As shown, the driving wheel 6 includes an outer wheel body 21 and a hub motor 22. The outer wheel body 21 is fixed on the outer rotor of the hub motor 22 and driven by the hub motor 22. The internal stator of the hub motor 22 is fixed on the motor support 23. The motor support 23 is rotated by a rotating shaft mechanism and is set in the middle of the lower side of the vehicle body 5.

[0037] The rotating shaft mechanism includes a rotating shaft sleeve 24, a rotating shaft slide 25, a second electric push rod 26 and a fixed sleeve 27. The rotating shaft mounting plate 8 is fixed to the upper end of the rotating shaft sleeve 24. The rotating shaft sleeve 24 is rotated and set in the middle position of the vehicle body 5 through the rotating shaft mounting plate 8. The upper end of the rotating shaft slide 25 is slidably set in the cylinder body of the lower end of the rotating shaft sleeve 24 and can slide up and down along the inner wall of the cylinder body of the rotating shaft sleeve 24. The lower end of the rotating shaft slide 25 is fixed to the motor support 23. The fixed sleeve 27 is sleeved on the outside of the rotating shaft slide 25 and is fixedly connected to the rotating shaft slide 25. The second electric push rod 26 is vertically fixed to the side of the rotating shaft sleeve 24 and the push rod end of the second electric push rod 26 is hinged to the fixed sleeve 27 to drive the rotating shaft slide 25 to rise and fall vertically in the rotating shaft sleeve 24. Since the cross-section of the tower is a circle, when towers of different specifications need to be welded, the height of the driving wheel 6 of the self-propelled vehicle body 3 also needs to be adjusted as the diameter of the tower changes, so that the arc formed by the driving wheel 6 and the driven wheels 7 on both sides can match the arc of the tower. Therefore, the second electric push rod 26 drives the fixed sleeve 27 to drive the rotating shaft slide rod 25 to rise and fall in the rotating shaft sleeve 24 to adjust the height of the driving wheel 6.

[0038] like Figure 7 and Figure 8 As shown, the circumferential surface of the outer wheel body 21 is provided with multiple electromagnet plates 28, each of which is V-shaped. Multiple electromagnet plates 28 are sequentially arranged on the circumference of the outer wheel body 21 along the same clockwise direction, and adjacent electromagnet plates 28 are separated by insulating, non-magnetic material. The electromagnet plate 28 at the bottom end of the outer wheel body 21 is powered by an electromagnet power supply mechanism. In this embodiment, the outer wheel body 21 itself is made of an insulating, non-magnetic material such as polyurethane. Then, a V-shaped groove is formed on the outer surface of the outer wheel body 21, and the electromagnet plates 28 are embedded in the V-shaped groove for installation.

[0039] The electromagnet power supply mechanism includes a circular power supply slot mounting bracket 29, multiple power supply slots 30 and power supply terminals 31. The number of power supply slots 30 is equal to the number of electromagnet pieces 28. The multiple power supply slots 30 are fixedly arranged in the circular power supply slot mounting bracket 29 and are evenly spaced along the circumference of the circular power supply slot mounting bracket 29. The circular power supply slot mounting bracket 29 is fixed on the outer rotor of the hub motor 22. Each power supply slot 30 is connected to the corresponding electromagnet piece 28 through a wire 32. One end of the power supply terminal 31 is fixed on the internal stator of the hub motor 22 and connected to the power supply. The other end of the power supply terminal 31 is slidably set in the power supply slot 30. When working, the hub motor 22 drives the outer wheel body 21 to rotate. During the rotation of the outer wheel body 21, the power supply terminal 31 always maintains its position due to being fixed on the stator, and the power supply slot 30 rotates synchronously with the outer wheel body 21 due to being fixed on the mover. At the same time, only one power supply slot 30 is always connected to the power supply terminal 31, so that only the electromagnet sheet 28 at the bottom is working, and the rest of the electromagnet sheets 28 are not working, thereby reducing energy consumption.

[0040] like Figure 9 As shown, the power supply slot 30 includes a first arc-shaped conductor piece 33, a second arc-shaped conductor piece 34, an insulating bolt 35, an insulating nut 36 and an insulating gasket 37. One end of the first arc-shaped conductor piece 33 and the second arc-shaped conductor piece 34 is provided with mutually parallel mounting portions. The insulating gasket 37 is provided between the mounting portions of the first arc-shaped conductor piece 33 and the second arc-shaped conductor piece 34. Screw holes are provided on the mounting portions of the first arc-shaped conductor piece 33 and the second arc-shaped conductor piece 34 and the insulating gasket 37. The insulating bolt 35 passes through the mounting portion of the first arc-shaped conductor piece 33. The power supply terminal 31 includes a spherical end 38 and a cylindrical terminal body 39. The contact portions of the spherical end 38 on both sides with the first and second arc-shaped conductor pieces 33 and 34 are conductors. The conductors on both sides of the spherical end 38 are separated by insulating material. The spherical end 38 is fixed to the end of the cylindrical terminal body 39. The other ends of the first and second arc-shaped conductor pieces 33 and 34 form an opening smaller than the diameter of the spherical end 38. During installation, the spherical end 38 of the power supply terminal 31 is inserted into the opening at the other end of the first and second arc-shaped conductor pieces 33 and 34 and then slides between the first and second arc-shaped conductor pieces 33 and 34. With this structure, only one set of power supply slots 30 and power supply terminals 31 is needed to realize the conductive structure of the electromagnet sheet 28 , making the overall power supply structure simpler and more compact, saving space for the driving wheel 6 .

[0041] The follower wheel 7 includes a universal wheel and a follower wheel bracket. The universal wheel is arranged at the lower end of the follower wheel bracket. The upper end of the follower wheel bracket is fixed at the four corners of the lower side of the vehicle body and the follower wheel bracket is bent and protruded outward.

[0042] The present invention provides an offshore wind turbine tower welding device, which simultaneously welds the inner and outer sides of the tower through an external tower welding device and an internal tower welding device, shortening the tower welding time and improving the tower welding efficiency. Moreover, since the welding on both sides adopts a structure of cutting 45-degree grooves on both sides, less waste is generated compared with cutting 45-degree grooves on one side, and the welding materials required for filling are also greatly reduced; the present invention drives the self-propelled vehicle body to move and turn through a driving wheel, and a plurality of follower wheels support the vehicle body and move with the driving wheel. The driving wheel can be raised and lowered to cope with towers of different diameters; the present invention detects whether the self-propelled vehicle body is offset through a pendulum. When offset occurs, the pendulum swings to drive the third gear to rotate and finally drives the driving wheel to perform steering adjustment so that the self-propelled vehicle body keeps moving in a straight line; the driving wheel of the present invention adopts an electromagnet sheet to be adsorbed on the inner wall of the tower to prevent the wheel body from slipping with the inner wall of the sleeve, thereby ensuring the synchronization of the welding robots on the inner and outer sides. The driving wheel is designed with a unique power supply structure, and only the electromagnet sheet at the bottom is energized for adsorption, which is simple to control and reduces energy consumption.

[0043] The above description is merely a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Although the present invention has been disclosed as a preferred embodiment as above, it is not intended to limit the present invention. Any technician familiar with the present profession can make some changes or modifications to equivalent embodiments of equivalent changes using the technical content disclosed above without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent replacement and improvement of the above embodiments made according to the technical essence of the present invention, within the spirit and principles of the present invention, without departing from the content of the technical solution of the present invention, shall still fall within the scope of protection of the technical solution of the present invention.

Claims

1. An offshore wind turbine tower welding device, characterized by: It includes an external tower welding device and an internal tower welding device. The internal tower welding device includes a self-propelled vehicle body and a welding robot. The welding robot is fixed on the self-propelled vehicle body. The self-propelled vehicle body includes a vehicle body, a driving wheel and a plurality of follower wheels. The driving wheel is arranged in the middle of the lower side of the vehicle body through a slewing mechanism, and the plurality of follower wheels are distributed around the lower side of the vehicle body. The first gear is engaged with the second gear, and the second gear is connected with the gear driving motor and is driven by the gear driving motor. When the upper side surface of the first gear abuts against the lower side surface of the rotating shaft mounting plate, the first gear meshes with the third gear, and the third gear is rotatably arranged on the vehicle body and driven by the third gear driving mechanism; The first gear is connected with the. second gear of the vehicle body to the first transmission gear and the second gear is connected with the transmission gear of the vehicle body to the first transmission gear. When the vehicle body is turned to the left, the first gear is turned to the first transmission gear and the second gear is connected with the transmission gear of the vehicle body to the first transmission gear.

2. The offshore wind turbine tower welding device according to claim 1, characterized in that: The pendulum is a fan-shaped pendulum.

3. The offshore wind turbine tower welding device according to claim 1, characterized in that: The driving wheel includes an outer wheel body and a hub motor. The outer wheel body is fixed on the outer rotor of the hub motor and driven by the hub motor. The internal stator of the hub motor is fixed on the motor support. The motor support is rotated by a shaft mechanism and is arranged in the middle of the lower side of the vehicle body.

4. The offshore wind turbine tower welding device according to claim 3, characterized in that: The rotating shaft mechanism includes a rotating shaft sleeve, a rotating shaft slide, a second electric push rod and a fixed sleeve. The rotating shaft mounting plate is fixed to the upper end of the rotating shaft sleeve. The rotating shaft sleeve is rotated and set in the middle position of the vehicle body through the rotating shaft mounting plate. The upper end of the rotating shaft slide is slidably set in the cylinder body of the lower end of the rotating shaft sleeve and can slide up and down along the inner wall of the cylinder body of the rotating shaft sleeve. The lower end of the rotating shaft slide is fixed to the motor support. The fixed sleeve is arranged on the outside of the rotating shaft slide and is fixedly connected to the rotating shaft slide. The second electric push rod is vertically fixed to the side of the rotating shaft sleeve and the push rod end of the second electric push rod is hinged to the fixed sleeve to drive the rotating shaft slide to rise and fall vertically in the rotating shaft sleeve.

5. The offshore wind turbine tower welding device according to claim 3, characterized in that: A plurality of electromagnet sheets are arranged on the circumferential surface of the outer wheel body, each of which is a V-shaped electromagnet sheet. The plurality of electromagnet sheets are arranged on the circumferential surface of the outer wheel body in the same clockwise order and adjacent electromagnet sheets are separated by insulating non-magnetic materials. The electromagnet sheet located at the lower end of the outer wheel body is powered by an electromagnet power supply mechanism.

6. The offshore wind turbine tower welding device according to claim 5, characterized in that: The electromagnet power supply mechanism includes a circular power supply slot mounting bracket, multiple power supply slots and power supply terminals. The number of power supply slots is equal to the number of electromagnet sheets. The multiple power supply slots are fixedly arranged in the circular power supply slot mounting bracket and are evenly spaced along the circumference of the circular power supply slot mounting bracket. Each power supply slot is connected to the corresponding electromagnet sheet through a wire. One end of the power supply terminal is fixed on the internal stator of the hub motor and connected to the power supply, and the other end of the power supply terminal is slidably arranged in the power supply slot.

7. The offshore wind turbine tower welding device according to claim 6, characterized in that: The power supply slot includes a first arc-shaped conductor piece, a second arc-shaped conductor piece, an insulating bolt, an insulating nut and an insulating gasket. One end of the first arc-shaped conductor piece and the second arc-shaped conductor piece is provided with mounting parts parallel to each other. The insulating gasket is arranged between the mounting parts of the first arc-shaped conductor piece and the second arc-shaped conductor piece. Screw holes are opened on the mounting parts of the first arc-shaped conductor piece and the second arc-shaped conductor piece and the insulating gasket. The insulating bolt passes through the screw holes of the mounting part of the first arc-shaped conductor piece, the insulating gasket and the second arc-shaped conductor piece and is then locked and fixed by the insulating nut. The power supply terminal includes a spherical end and a cylindrical terminal body. The contact parts of the two sides of the spherical end with the first arc-shaped conductor piece and the second arc-shaped conductor piece are conductors. The conductors on both sides of the spherical end are separated by insulating material. The spherical end is fixed to the end of the cylindrical terminal body. The other ends of the first arc-shaped conductor piece and the second arc-shaped conductor piece form an opening smaller than the diameter of the spherical end.

8. The offshore wind turbine tower welding device according to claim 1, characterized in that: The follower wheel includes a universal wheel and a follower wheel bracket. The universal wheel is arranged at the lower end of the follower wheel bracket. The upper end of the follower wheel bracket is fixed at the four corners of the lower side of the vehicle body and the follower wheel bracket is bent and protruded outward.

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