Welding equipment for steel pipes

Abstract

The invention relates to the field of steel pipe welding, and discloses a steel pipe welding device which comprises a workbench, a middle groove is formed in the middle of the upper face of the workbench, multi-directional limiting structures are arranged on the left side and the right side of the upper face of the workbench correspondingly, and U-shaped plates are fastened to the left side and the right side of the upper face of the workbench through bolts correspondingly; a pressing structure is arranged on the U-shaped plate, a rotating structure is arranged above the middle of the interior of the middle groove, abutting limiting structures are arranged on the two sides of the interior of the middle groove, and a collecting frame is arranged on the lower portion of the interior of the workbench. The steel pipes can be pressed on the multi-directional limiting structure, so that the steel pipes in different shapes can be directly limited and pressed, the operation is more labor-saving and convenient, the working cost is low, and the working efficiency is higher.

Description

Technical Field

[0001] This invention relates to the technical field of steel pipe welding, and in particular to a welding device for steel pipes. Background Technology

[0002] Steel pipe welding is a process that melts and fuses the two ends of a steel pipe through heating or pressurization to form a permanent connection. During welding, an electric arc or high temperature is used to melt the welding rod or base metal, melting the joint between the two ends of the steel pipe and then cooling and solidifying to form a strong connection. Welding equipment is used when welding steel pipes.

[0003] In existing steel pipe welding equipment, a replaceable limiting block is set in the connecting groove of the fixed block, and a limiting groove is set on the limiting block. The limiting groove can improve the firmness of the steel pipe segment on the limiting block. By replacing different limiting blocks, different steel pipe segments can be accommodated, thus improving the applicability of the welding fixture. A replaceable pressure plate is set on the connecting rod of the cylinder, and upper pressure grooves are set at both ends of the pressure plate. The upper pressure grooves can further improve the firmness of the steel pipe segment, thereby improving the welding quality of the steel pipe segment. By replacing different pressure plates according to different shapes of steel pipe segments, the applicability of the welding fixture is further expanded, and the cost of manufacturing multiple welding fixtures is reduced.

[0004] However, in actual use, different pressure plates need to be replaced, which not only increases the operation process and reduces work efficiency, but also requires the pressure plates to be customized according to the actual situation, which increases the cost. In addition, the pressure plates need to be moved to the corresponding positions for welding according to the actual situation, which is quite troublesome. Therefore, there are areas for improvement. Summary of the Invention

[0005] To address the problems mentioned in the background section, the present invention provides a welding device for steel pipes.

[0006] The present invention provides a welding device for steel pipes, which adopts the following technical solution:

[0007] A welding device for steel pipes includes a workbench with a central groove in the middle. Multi-directional limiting structures are provided on both the left and right sides of the workbench. U-shaped plates are bolted to both the left and right sides of the workbench, and a pressing structure is provided on the U-shaped plates. A rotating structure is provided at the upper center of the central groove, and abutting and limiting structures are provided on both sides of the central groove. A collection frame is provided at the lower center of the workbench.

[0008] The multi-directional limiting structure includes two support platforms mounted on the workbench. Multiple limiting rods move through the support platforms and are arranged in an array on the workbench. The top of each limiting rod is hemispherical. A limiting ring is fixedly fitted on the limiting rod near the center. A bottom block is provided at the bottom of each limiting rod. A spring is fitted on each limiting rod, and the two ends of the spring are respectively connected to the bottom block and the support platform.

[0009] The clamping structure includes a hydraulic cylinder mounted on a U-shaped plate, with the bottom end of the hydraulic cylinder's output shaft connected to a pressure plate.

[0010] Preferably, the clamping and limiting structure includes a bidirectional screw that rotates through the middle of the worktable. The two ends of the bidirectional screw have opposite thread directions. Handwheels are provided at both ends of the bidirectional screw that protrude from the worktable. Guide rods are connected to the left and right sides of the inner wall of the middle groove. Two movable plates are movably sleeved on the two sets of guide rods. A threaded groove for the bidirectional screw to pass through is opened in the middle of the movable plate. Vertical plates are fastened to the left and right sides of each movable plate by bolts. Two first fixed frames are fixedly passed through the vertical plates. A limiting cylinder is movably sleeved on each of the first fixed frames.

[0011] Preferably, the rotating structure includes connecting plates connected to the middle of the inner walls on both the front and rear sides of the intermediate groove, fixing rings are installed at the top of the two connecting plates, a rotating ring is rotatably arranged inside the fixing ring, a welding structure is provided on the inner wall of the rotating ring, and a driving structure is provided on the fixing ring.

[0012] Preferably, the drive structure includes a mounting plate connected to the side of the fixed ring, a motor is mounted on the mounting plate, a first gear is fixedly sleeved on one end of the motor output shaft, and a gear ring is fixedly sleeved on one end of the rotating ring, with the first gear and the teeth on the gear ring meshing together.

[0013] Preferably, the welding structure includes two inner plates connected to the inner wall of the rotating ring. A mounting block is connected to one side of the inner plate near the inner wall of the rotating ring. A second fixing frame is connected to the mounting block. A cylinder is installed on the inner wall of the second fixing frame. One end of the cylinder's output shaft is connected to a moving frame. A welding torch is installed inside the moving frame. A first shielding cover is fixedly installed on the welding torch near the welding head. A spray cooling structure is provided on the inner plate.

[0014] Preferably, the spray cooling structure includes a through groove formed on the inner plate, a movable block slidably disposed in the through groove, a connecting block connected to the movable block, a second shield installed at one end of the connecting block, a water storage tank disposed on the second shield, a water pump outlet connected to the water storage tank, a spray nozzle installed at one end of the water supply pipe inserted into the second shield, and a movable structure disposed in the through groove.

[0015] Preferably, the movable structure includes a rotating rod rotatably connected between the two end walls of the through groove, a spiral groove is formed on the rotating rod, a plug is fixedly inserted into the movable block, one end of the plug is movably inserted into the spiral groove, and a transmission structure is provided between the rotating rod and the movable frame.

[0016] Preferably, the transmission structure includes two sliding grooves formed on the inner plate, with sliding blocks slidably mounted in the grooves. A connecting strip connects the two sliding blocks, and a driving strip is connected to the middle of the connecting strip. A second gear is fixedly sleeved on the rotating rod near the driving strip, and the second gear meshes with the teeth on the driving strip. One end of the connecting strip is connected to a driving plate, and a first driving groove is formed on the driving plate. A second driving groove is formed on the driving plate, connecting one end of the first driving groove. An L-shaped rod is connected to the top of the moving frame, and one end of the L-shaped rod is movably inserted into the first driving groove.

[0017] In summary, the present invention has the following beneficial technical effects:

[0018] 1. By setting up a multi-directional limiting structure and a clamping structure, steel pipes of different shapes can be directly placed on multiple limiting rods of the multi-directional limiting structure during welding. In conjunction with the clamping structure, the steel pipes can be clamped onto the multi-directional limiting structure. This allows for direct limiting and clamping of steel pipes of different shapes, making the operation more labor-saving, convenient, cost-effective, and efficient.

[0019] 2. By setting a clamping and limiting structure, the present invention can clamp and limit two steel pipes to be welded to each other at one end, thus ensuring the welding quality.

[0020] 3. This invention, by setting up a welding structure, a rotating structure, and a driving structure, drives the rotating structure to rotate, thereby driving the welding structure to perform rotational welding, making the welding of steel pipes more thorough and comprehensive, and improving the welding quality.

[0021] 4. This invention, by setting up a spray cooling structure, a moving structure, and a transmission structure, utilizes the spray cooling structure to spray and cool the welded steel pipe. Furthermore, through the moving and transmission structures, during the resetting process of the welded structure, the second shield of the spray cooling structure is automatically moved to fit tightly onto the steel pipe, providing shielding during spraying and preventing water from splashing onto the workbench, thus reducing work quality. Simultaneously, when the welded structure is fully reset, the spray cooling structure can be automatically moved in the opposite direction to reset, thereby facilitating the removal of the welded steel pipe. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the structure of a welding device for steel pipes according to an embodiment of the present invention;

[0023] Figure 2 This is a schematic diagram of the structure at the support platform in an embodiment of the present invention;

[0024] Figure 3 This is an embodiment of the present invention. Figure 2 Enlarged view of the structure at point A;

[0025] Figure 4 This is a schematic diagram of the structure of the intermediate groove in an embodiment of the present invention;

[0026] Figure 5 This is a schematic diagram of the structure at the fixing ring in an embodiment of the present invention;

[0027] Figure 6 This is a schematic diagram of the structure of the inner plate in an embodiment of the present invention;

[0028] Figure 7 This is an embodiment of the present invention. Figure 6 Enlarged view of the structure at point B.

[0029] Explanation of reference numerals in the attached drawings: 1. Workbench; 2. Support platform; 3. U-shaped plate; 4. Hydraulic cylinder; 5. Pressure plate; 6. Limiting rod; 7. Limiting ring; 8. Base block; 9. Spring; 10. Intermediate groove; 11. Collection frame; 12. Bidirectional screw; 13. Handwheel; 14. Guide rod; 15. Moving plate; 16. Vertical plate; 17. First fixed frame; 18. Limiting cylinder; 19. Connecting plate; 20. Fixing ring; 21. Rotating ring; 22. Inner plate; 23. Mounting plate; 24. Motor; 25. First gear; 26. 27. Gear ring; 28. Mounting block; 29. ​​Second fixed frame; 30. Cylinder; 31. Moving frame; 32. Welding torch; 33. First shield; 34. Through groove; 35. Moving block; 36. Connecting block; 37. Second shield; 38. Nozzle; 39. Water storage cylinder; 40. Insert rod; 41. Rotating rod; 42. Spiral groove; 43. Sliding groove; 44. Connecting strip; 45. Second tooth; 46. Driving strip; 47. Driving plate; 48. L-shaped rod; 49. First driving groove; 50. Second driving groove. Detailed Implementation

[0030] The following is in conjunction with the appendix Figures 1-7 The present invention will be described in further detail below.

[0031] Reference Figures 1-7 This invention discloses a welding device for steel pipes, including a workbench 1, a central groove 10 formed in the middle of the workbench 1, multi-directional limiting structures on both the left and right sides of the workbench 1, U-shaped plates 3 fastened to both the left and right sides of the workbench 1 by bolts, a pressing structure on the U-shaped plates 3, a rotating structure in the upper middle of the central groove 10, abutting and limiting structures in both sides of the central groove 10, and a collection frame 11 in the lower part of the workbench 1.

[0032] The multi-directional limiting structure includes two support platforms 2 set on the workbench 1. Multiple limiting rods 6 move through the support platforms 2. The multiple limiting rods 6 are arranged in an array on the workbench 1. The top of each limiting rod 6 is hemispherical. A limiting ring 7 is fixedly sleeved on the limiting rod 6 near the middle. A bottom block 8 is set at the bottom of each limiting rod 6. A spring 9 is sleeved on each limiting rod 6. The two ends of the spring 9 are respectively connected to the bottom block 8 and the support platform 2.

[0033] The clamping structure includes a hydraulic cylinder 4 mounted on a U-shaped plate 3, with the bottom end of the output shaft of the hydraulic cylinder 4 connected to a pressure plate 5;

[0034] The clamping and limiting structure includes a bidirectional screw 12 that rotates through the middle of the worktable 1. The two ends of the bidirectional screw 12 have opposite thread directions. Handwheels 13 are provided at both ends of the bidirectional screw 12 that protrude from the worktable 1. Guide rods 14 are connected to the left and right sides of the inner wall of the middle groove 10. Two movable plates 15 are movably sleeved on the two sets of guide rods 14. The movable plates 15 have threaded grooves in the middle for the bidirectional screw 12 to pass through. Each movable plate 15 has a vertical plate 16 fastened to its left and right sides by bolts. Two first fixed frames 17 are fixedly passed through the vertical plate 16. A limiting sleeve 18 is movably sleeved on each first fixed frame 17. First, the two steel pipes are placed directly onto the two... The two steel pipes are positioned on the limit rod 6 and adjusted so that the ends of the two steel pipes to be welded are pressed together. Then, the hydraulic cylinder 4 is started to drive the pressure plate 5 to move down. The moving pressure plate 5 squeezes the steel pipes and pushes the corresponding limit rod 6 down. After the upper limit ring 7 of part of the limit rod 6 moves down and fits against the support platform 2, the pressure plate 5 stops moving down. In this way, by using the pressure of the pressure plate 5 and the limit rod 6 to limit the steel pipes, steel pipes of different shapes can be directly pressed. Then, the handwheel 13 is used to rotate the double screw 12, and the two moving plates 15 drive the limit cylinder 18 to move and fit against the two steel pipes, ensuring that the steel pipes are more tightly fitted and improving the welding quality.

[0035] See Figure 1 , Figure 4 , Figure 5 and Figure 6 The rotating structure includes a connecting plate 19 connected to the middle of the inner walls of the front and rear sides of the intermediate groove 10. A fixing ring 20 is installed at the top of the two connecting plates 19. A rotating ring 21 is rotatably arranged inside the fixing ring 20. A welding structure is provided on the inner wall of the rotating ring 21. A driving structure is provided on the fixing ring 20.

[0036] The drive structure includes a mounting plate 23 connected to the side of the fixed ring 20, a motor 24 mounted on the mounting plate 23, a first gear 25 fixedly sleeved on one end of the output shaft of the motor 24, and a gear ring 26 fixedly sleeved on one end of the rotating ring 21. The first gear 25 and the teeth on the gear ring 26 are meshed and connected.

[0037] The welding structure includes two inner plates 22 connected to the inner wall of the rotating ring 21. A mounting block 27 is connected to one side of the inner plate 22 near the inner wall of the rotating ring 21. A second fixed frame 28 is connected to the mounting block 27. A cylinder 29 is mounted on the inner wall of the second fixed frame 28. One end of the output shaft of the cylinder 29 is connected to a moving frame 30. A welding torch 31 is mounted inside the moving frame 30. A first shielding cover 32 is fixedly installed on the welding torch 31 near the welding head. A spray cooling structure is provided on the inner plate 22. During welding, the cylinder 29 is activated to move the first shielding cover 32 close to the position on the steel pipe to be welded. The welding torch 31 is then activated to perform welding on the steel pipe. Simultaneously, the motor 24 on the mounting plate 23 drives the rotating ring 21 to rotate within the fixed ring 20, causing the welding torch 31 to perform welding work on different positions on the steel pipe, resulting in more comprehensive welding. Furthermore, the first shielding cover 32 can be used to shield the debris and strong light generated during welding, improving the quality of the working environment.

[0038] See Figure 1 , Figure 6 and Figure 7 The spray cooling structure includes a through groove 33 on the inner plate 22, a movable block 34 slidably disposed in the through groove 33, a connecting block 35 connected to the movable block 34, a second shield 36 installed at one end of the connecting block 35, a water storage tank 38 disposed on the second shield 36, a water pump outlet end of the water storage tank 38 connected to a water supply pipe, a nozzle 37 installed at one end of the water supply pipe inserted into the second shield 36, and a movable structure disposed in the through groove 33.

[0039] The movable structure includes a rotating rod 40 rotatably connected between the two end walls of the through groove 33, a spiral groove 41 is opened on the rotating rod 40, a plug rod 39 is fixedly inserted into the movable block 34, one end of the plug rod 39 is movably inserted into the spiral groove 41, and a transmission structure is provided between the rotating rod 40 and the movable frame 30.

[0040] The transmission structure includes two slide grooves 42 formed on the inner plate 22. Slide blocks 43 are slidably mounted on the slide grooves 42. A connecting strip 44 connects the two slide blocks 43. A drive strip 46 is connected to the middle of the connecting strip 44. A second gear 45 is fixedly sleeved on the rotating rod 40 near the drive strip 46. The second gear 45 meshes with the teeth on the drive strip 46. One end of the connecting strip 44 is connected to a drive plate 47. A first drive groove 49 is formed on the drive plate 47. A second drive groove is formed on the drive plate 47 that connects to one end of the first drive groove 49. 50. An L-shaped rod 48 is connected to the upper part of the movable frame 30. One end of the L-shaped rod 48 is movably inserted into the first driving groove 49. After welding, the cylinder 29 drives the first shield 32 to move in the reverse direction and reset. During the reverse movement and reset process of the first shield 32 and the movable frame 30 as a whole, the movable frame 30 drives one end of the L-shaped rod 48 to move towards the mounting block 27 in the second driving groove 50. By using the pressure of one end of the L-shaped rod 48 against the groove wall of the second driving groove 50, the driving plate 47 is pushed to move, and the driving bar 46 and the second... Gear 45 drives rotating rod 40 to rotate. Since one end of the insert rod 39 on the moving block 34 is slidably positioned in the spiral groove 41 on the rotating rod 40, it drives the second shield 36 to move and press against the steel pipe. At this time, the first shield 32 stops moving. This activates the water pump on the water storage tank 38, channeling water from the tank to the nozzle 37, which sprays it onto the steel pipe to cool the welded areas. The second shield 36 also shields the sprayed water, preventing it from splashing onto the workbench 1 and improving efficiency. In addition to improving work quality, the motor 24 can be started to drive the rotating ring 21 to rotate, spraying water to cool various positions on the steel pipe. After cooling, the cylinder 29 continues to drive the first shield 32 to move in the reverse direction and reset, and drives one end of the L-shaped rod 48 to slide into the first driving groove 49. The L-shaped rod 48 presses the groove wall of the first driving groove 49, thereby driving the driving plate 47 to reset, thereby driving the rotating rod 40 to rotate in the reverse direction, so as to drive the second shield 36 to move in the reverse direction and reset automatically. In this way, the welding work of the steel pipe can be realized.

[0041] The implementation principle of a welding device for steel pipes according to an embodiment of the present invention is as follows: First, two steel pipes are placed directly on two sets of limiting rods 6, and the positions of the two steel pipes are adjusted so that the ends of the two steel pipes to be welded are close together. Then, the hydraulic cylinder 4 is activated to drive the pressure plate 5 to move downward. The moving pressure plate 5 squeezes the steel pipes, pushing the corresponding limiting rods 6 downward. After the upper limit rings 7 of some limiting rods 6 move downward and fit against the support platform 2, the pressure plate 5 stops moving downward. In this way, by using the pressing of the pressure plate 5, combined with the limiting rods 6 to limit the steel pipes, steel pipes of different shapes can be directly pressed. Next, the handwheel 13 is used to rotate the bidirectional screw 12, and the two moving plates 15 drive... The limiting cylinder 18 moves and presses against the two steel pipes, ensuring a tighter fit and improving welding quality. Next, the cylinder 29 is activated, moving the first shielding cover 32 to the welding position on the steel pipe. The welding torch 31 is then activated to begin welding. Simultaneously, the motor 24 on the mounting plate 23 drives the rotating ring 21 to rotate within the fixed ring 20, causing the welding torch 31 to weld different positions on the steel pipe, resulting in more comprehensive welding. The first shielding cover 32 also shields the welding process from debris and strong light, improving the working environment. Then, the cylinder 29 moves the first shielding cover 32 in the reverse direction to reset, and the first shielding cover 32 and the moving frame... During the reverse movement and reset process of the entire assembly, the moving frame 30 drives one end of the L-shaped rod 48 to move towards the mounting block 27 in the second driving groove 50. The pressure of the L-shaped rod 48 against the wall of the second driving groove 50 pushes the driving plate 47 to move. This, in turn, drives the rotating rod 40 to rotate via the driving bar 46 and the second gear 45. Since one end of the insert rod 39 on the moving block 34 is slidably positioned in the spiral groove 41 on the rotating rod 40, the second shield 36 moves and presses against the steel pipe. At this point, the first shield 32 stops moving. This activates the water pump on the water storage tank 38, channeling water from the tank to the nozzle 37, which then sprays it onto the steel pipe. Cooling is performed at the welding position on the pipe, and the second shield 36 blocks the sprayed water to prevent it from splashing onto the workbench 1, thus improving work quality. At the same time, the motor 24 can be started to drive the rotating ring 21 to rotate, spraying water to cool various positions on the steel pipe. After cooling, the cylinder 29 continues to drive the first shield 32 to move in the reverse direction and reset, and drives one end of the L-shaped rod 48 to slide into the first driving groove 49. The L-shaped rod 48 presses against the wall of the first driving groove 49, thereby driving the driving plate 47 to reset, which in turn drives the rotating rod 40 to rotate in the reverse direction, thereby driving the second shield 36 to automatically move in the reverse direction and reset. In this way, the welding work of the steel pipe can be realized.

[0042] The above are all preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Therefore, all equivalent changes made in accordance with the structure, shape and principle of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A welding device for steel pipes, comprising a workbench (1), characterized in that: A central groove (10) is provided in the middle of the workbench (1). Multi-directional limiting structures are provided on both the left and right sides of the workbench (1). U-shaped plates (3) are fastened to both the left and right sides of the workbench (1) by bolts. A pressing structure is provided on the U-shaped plate (3). A rotating structure is provided in the upper middle of the central groove (10). A clamping limiting structure is provided on both sides of the central groove (10). A collection frame (11) is provided in the lower part of the workbench (1). The multi-directional limiting structure includes two support platforms (2) set on the workbench (1). Multiple limiting rods (6) move through the support platforms (2). The multiple limiting rods (6) are arranged in an array on the workbench (1). The top of each limiting rod (6) is hemispherical. A limiting ring (7) is fixedly sleeved on the limiting rod (6) near the middle. A bottom block (8) is set at the bottom of each limiting rod (6). A spring (9) is sleeved on each limiting rod (6). The two ends of the spring (9) are respectively connected to the bottom block (8) and the support platform (2). The clamping structure includes a hydraulic cylinder (4) mounted on a U-shaped plate (3), and the bottom end of the output shaft of the hydraulic cylinder (4) is connected to a pressure plate (5).

2. The welding equipment for steel pipes according to claim 1, characterized in that: The clamping and limiting structure includes a bidirectional screw (12) that rotates through the middle of the workbench (1). The two sections of the bidirectional screw (12) have opposite thread directions. A handwheel (13) is provided on both ends of the bidirectional screw (12) that protrude from the workbench (1). Guide rods (14) are connected to the left and right sides of the inner wall of the middle groove (10). Two movable plates (15) are movably sleeved on the two sets of guide rods (14). A threaded groove for the bidirectional screw (12) to pass through is opened in the middle of the movable plate (15). A vertical plate (16) is fastened to the left and right sides of each movable plate (15) by bolts. Two first fixed frames (17) are fixedly passed through the vertical plate (16). A limiting sleeve (18) is movably sleeved on each first fixed frame (17).

3. The welding equipment for steel pipes according to claim 1, characterized in that: The rotating structure includes connecting plates (19) connected to the middle of the inner walls of the front and rear sides of the intermediate groove (10). Fixing rings (20) are installed at the top of the two connecting plates (19). A rotating ring (21) is rotatably arranged inside the fixing ring (20). A welding structure is provided on the inner wall of the rotating ring (21). A driving structure is provided on the fixing ring (20).

4. The welding equipment for steel pipes according to claim 3, characterized in that: The drive structure includes a mounting plate (23) connected to the side of the fixed ring (20), a motor (24) is mounted on the mounting plate (23), a first gear (25) is fixedly sleeved on one end of the output shaft of the motor (24), and a toothed ring (26) is fixedly sleeved on one end of the rotating ring (21), and the teeth of the first gear (25) and the toothed ring (26) are meshed together.

5. The welding equipment for steel pipes according to claim 1, characterized in that: The welding structure includes two inner plates (22) connected to the inner wall of the rotating ring (21). A mounting block (27) is connected to one side of the inner plate (22) near the inner wall of the rotating ring (21). A second fixing frame (28) is connected to the mounting block (27). A cylinder (29) is installed on the inner wall of the second fixing frame (28). One end of the output shaft of the cylinder (29) is connected to a moving frame (30). A welding gun (31) is installed in the moving frame (30). A first shielding cover (32) is fixedly installed on the welding gun (31) near the welding head. A spray cooling structure is provided on the inner plate (22).

6. The welding equipment for steel pipes according to claim 5, characterized in that: The spray cooling structure includes a through groove (33) on the inner plate (22), a movable block (34) is slidably arranged in the through groove (33), a connecting block (35) is connected to the movable block (34), a second shield (36) is installed at one end of the connecting block (35), a water storage tank (38) is arranged on the second shield (36), a water pump outlet end of the water storage tank (38) is connected to a water delivery pipe, a nozzle (37) is installed at one end of the water delivery pipe inserted into the second shield (36), and a movable structure is arranged in the through groove (33).

7. The welding equipment for steel pipes according to claim 6, characterized in that: The movable structure includes a rotating rod (40) rotatably connected between the two end walls of the through groove (33), a spiral groove (41) is opened on the rotating rod (40), a plug rod (39) is fixedly inserted into the movable block (34), one end of the plug rod (39) is movably inserted into the spiral groove (41), and a transmission structure is provided between the rotating rod (40) and the movable frame (30).

8. The welding equipment for steel pipes according to claim 7, characterized in that: The transmission structure includes two sliding grooves (42) on the inner plate (22), with sliding blocks (43) slidably mounted on the sliding grooves (42). A connecting strip (44) is connected between the two sliding blocks (43). A driving strip (46) is connected to the middle of the connecting strip (44). A second gear (45) is fixedly mounted on the rotating rod (40) near the driving strip (46). The second gear (45) meshes with the teeth on the driving strip (46). One end of the connecting strip (44) is connected to a driving plate (47). A first driving groove (49) is opened on the driving plate (47). A second driving groove (50) is opened on the driving plate (47) and connects to one end of the first driving groove (49). An L-shaped rod (48) is connected to the top of the moving frame (30). One end of the L-shaped rod (48) is movably inserted into the first driving groove (49).

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