Large-diameter galvanized steel pipe inner opening welding seam polishing device

Abstract

The invention relates to the technical field of weld joint grinding, and discloses a large-diameter galvanized steel pipe inner opening weld joint grinding device which comprises an auxiliary conveying mechanism and a weld joint treatment mechanism, the auxiliary conveying mechanism conveys a steel pipe in a rotating mode, and the weld joint treatment mechanism comprises a pre-treatment mechanism, a connecting frame and a post-treatment mechanism. A driving mechanism and a grinding mechanism are arranged on the pre-treatment mechanism, a spraying mechanism and a welding scrap cleaning mechanism are arranged on the post-treatment mechanism, the driving mechanism drives the grinding mechanism and the spraying mechanism to grind and spray a spiral welding seam of a steel pipe, and the welding scrap cleaning mechanism cleans welding scraps before spraying after grinding. According to the device, the problems of polishing, cleaning and anti-corrosion pretreatment before the inner opening welding seam of the large-diameter galvanized steel pipe is galvanized are efficiently solved, multi-procedure collaborative operation is achieved by integrating the functions of auxiliary conveying, pretreatment polishing, welding scrap cleaning, aftertreatment spraying and the like, and the adaptability to different pipe diameters and the operation stability are greatly improved.

Description

Technical Field

[0001] This invention relates to the field of weld grinding technology, specifically to a device for grinding the inner weld seam of a large-diameter galvanized steel pipe. Background Technology

[0002] Large-diameter galvanized steel pipes are mostly non-standard customized steel pipes. Their manufacturing often employs a spiral welded pipe galvanizing process, where coiled material is first formed into a steel pipe through spiral conveying and welding, followed by overall galvanizing to enhance corrosion resistance. During the spiral welding process, the high temperature generated by submerged arc welding directly damages the temporary anti-corrosion layer pre-installed on the coil surface, leaving the weld seam and surrounding substrate unprotected. These exposed substrates are highly susceptible to oxidation and corrosion from contact with air and moisture during the pre-galvanizing storage phase. Without treatment, the rust layer will affect the adhesion of the subsequent galvanized layer, leading to peeling and flaking, severely reducing the overall corrosion resistance and service life of the steel pipe. Therefore, the weld seam and surrounding rusted areas must be ground before galvanizing.

[0003] Currently, the grinding of the inner weld seams of large-diameter galvanized steel pipes mainly relies on manual grinding and traditional grinding equipment, both of which have significant shortcomings. For manual grinding, the limited operating space at the inner end of the large-diameter steel pipe makes the work extremely difficult and inefficient, failing to meet the demands of mass production. Existing grinding equipment suffers from multiple defects: firstly, poor adaptability, with most equipment designed for standard pipe diameters, lacking the flexibility to adjust to different inner diameters of non-standard large-diameter steel pipes, making it difficult to accurately conform to the arc-shaped contour of the inner pipe and the continuous direction of the spiral weld seam; secondly, limited grinding precision, lacking an adaptive adjustment structure, unable to handle weld seam protrusions, depressions, and arc-shaped changes, easily resulting in grinding dead angles and making it difficult to achieve a smooth weld surface.

[0004] The aforementioned shortcomings of manual grinding and existing equipment have led to problems such as unstable quality, low efficiency, and high cost in the grinding of the inner weld seams of large-diameter galvanized steel pipes, making it difficult to meet the requirements of industrial production for product quality and production efficiency. Therefore, there is an urgent need for a special grinding device with strong adaptability, high grinding precision, and smooth process connection. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to overcome the above-mentioned difficulties and provide a grinding device for the inner weld seam of a large-diameter galvanized steel pipe.

[0006] To solve the above-mentioned technical problems, the technical solution provided by the present invention is as follows: a grinding device for the inner weld of a large-diameter galvanized steel pipe, comprising an auxiliary conveying mechanism and a weld treatment mechanism. The auxiliary conveying mechanism rotates and conveys the steel pipe. The weld treatment mechanism comprises a pre-treatment mechanism, a connecting frame, and a post-treatment mechanism. The pre-treatment mechanism is equipped with a driving mechanism and a grinding mechanism, and the post-treatment mechanism is equipped with a spraying mechanism. The driving mechanism drives the grinding mechanism and the spraying mechanism to grind and spray the spiral weld of the steel pipe. The pre-processing mechanism includes a movable base frame that moves inside a steel pipe. The movable base frame remains relatively stationary with respect to the auxiliary conveying mechanism. The post-processing mechanism includes a functional frame, and a connecting frame connects the movable base frame and the functional frame. The grinding mechanism includes an adjustment table, a drive shaft, a grinding head, and a grinding plate. The adjustment table is adjustablely mounted on a movable base. The transmission mechanism is rotatably mounted on the adjustment table and is connected to the drive mechanism. The transmission mechanism drives the grinding head and the grinding plate to rotate synchronously.

[0007] As an improvement: the transmission mechanism (73) includes a transmission shaft (731), a second gear (734) and a turntable (735). The transmission shaft (731) is connected to the drive mechanism (6). The bottom of the transmission shaft (731) is connected to the grinding head (74). A rotating cylinder is provided at the bottom of the adjustment table. Multiple connecting rods are hinged at the bottom of the rotating cylinder. The grinding plate is hinged to the other end of the connecting rod. An elastic telescopic rod is hinged between the connecting rod and the outside of the rotating cylinder. The second gear (734) and the turntable (735) are rotatably located inside the adjustment table (71). The transmission shaft (731) is provided with a first gear (733) that meshes with the second gear (734). The inner side of the turntable (735) is provided with a gear ring (736) that meshes with the second gear (734).

[0008] As an improvement: According to claim 2, a grinding device for the inner weld of a large-diameter galvanized steel pipe is characterized in that: the transmission mechanism further includes a second gear and a turntable, a rotating cylinder (76) is rotatably provided at the bottom of the adjustment platform (71), the second gear and the turntable are rotatably provided inside the adjustment platform, a first gear that meshes with the second gear is provided on the transmission shaft, a toothed ring that meshes with the second gear is provided on the inner side of the turntable, a locking platform (761) is provided at the top of the rotating cylinder (76), a locking groove (737) that is inserted and matched with the locking platform (761) is provided at the bottom of the turntable (735), a plurality of connecting rods (77) are hinged at the bottom of the rotating cylinder (76), the grinding plate (75) is hinged to the other end of the connecting rod (77), and an elastic telescopic rod (78) is hinged between the connecting rod (77) and the outer side of the rotating cylinder (76).

[0009] As an improvement: the drive mechanism includes a second motor, a first drive shaft, and a second drive shaft. The second motor is fixed on the movable base. The first drive shaft is rotatably mounted on the movable base and the post-processing mechanism. The second drive shaft is rotatably mounted on the movable base. The output end of the second motor is connected to the first drive shaft. The first drive shaft is provided with a bevel gear. The second drive shaft is provided with a third bevel gear that meshes with the first bevel gear. The top of the drive shaft is provided with a spline shaft. The bottom of the second drive shaft is provided with a spline groove that mates with the spline shaft.

[0010] As an improvement: the spraying mechanism includes a spraying box, a turntable and a rotating cylinder. The spraying box is mounted on a functional frame, and a support frame is mounted on the functional frame. The rotating cylinder is rotatably mounted on the support frame. The bottom of the rotating cylinder is provided with a bevel gear four, and one end of the drive shaft is provided with a bevel gear two that meshes with the bevel gear four. The turntable is mounted on the top of the rotating cylinder, and a nozzle is provided on the turntable. The spraying box supplies material to the nozzle.

[0011] As an improvement: the rotating cylinder is equipped with a fixed tube, which is connected to the functional frame. One end of the fixed tube is connected to the feeder inside the spray box through a feed pipe, and the other end is equipped with a ball table that rotates with the ball groove at the bottom of the turntable. The internal channel of the ball table is connected to the turntable and the fixed tube.

[0012] As an improvement: the top of the mobile base is provided with an adjustable height support frame, and the mobile base, support frame and functional frame are all provided with foot plates, and multiple inclined rollers are rotatably provided on the foot plates.

[0013] As an improvement: the connecting frame is provided with a mounting plate, and multiple hydraulic cylinders are inclinedly mounted on the mounting plate, with a push plate hinged to the output end of the hydraulic cylinders.

[0014] As an improvement: the functional frame is equipped with a welding slag cleaning mechanism, which includes a negative pressure box and a suction platform. Both the negative pressure box and the suction platform are fixed on the functional frame, and the suction platform is connected to the fan inside the negative pressure box through an air duct.

[0015] The advantages of this invention compared to existing technologies are as follows: This device efficiently solves the problems of grinding, cleaning, and anti-corrosion pretreatment of the inner weld seam of large-diameter galvanized steel pipes before galvanizing. By integrating auxiliary conveying, pretreatment grinding, weld slag cleaning, and post-treatment spraying functions, it achieves multi-process collaborative operation, significantly improving adaptability to different pipe diameters and operational stability. It ensures uniform and precise weld seam treatment quality, significantly improves production efficiency, reduces labor costs and quality risks, and meets the needs of industrialized mass production. Specifically: 1. The adjustable height support frame, grinding plate with elastic telescopic rod and tilting roller structure can flexibly adapt to non-standard large-diameter steel pipes with different inner diameters. The grinding plate can adapt to the inner arc surface of the steel pipe and the spiral weld direction, avoiding grinding dead angles and solving the problem of poor adaptability of traditional equipment. 2. The drive mechanism drives the grinding head and the grinding plate to rotate synchronously in opposite directions. First, it powerfully removes the weld bead protrusions, and then it finely trims the edges. With the stable positioning of the fixing mechanism, it avoids uneven grinding depth. At the same time, the power transmission is uninterrupted, the operation is highly continuous, and the efficiency is far superior to manual grinding. 3. The welding slag cleaning mechanism can remove grinding residue in time to avoid contaminating the weld; the spraying mechanism completes the anti-corrosion pretreatment at the same time, forming a dense coating to prevent rust before galvanizing, solving the coating defect problem caused by the disconnection of traditional processes, and improving the adhesion of the subsequent galvanized layer. 4. Reduce manual intervention, lower labor intensity and dust hazards; avoid excessive grinding that damages the substrate or rework caused by incomplete grinding, reduce material waste, indirectly extend the overall service life of the steel pipe, and reduce comprehensive production and maintenance costs. Attached Figure Description

[0016] Figure 1 This is a structural diagram illustrating the process of using this invention.

[0017] Figure 2 This is a schematic diagram of the structure of the present invention.

[0018] Figure 3 This is a schematic diagram of the auxiliary conveying mechanism of the present invention.

[0019] Figure 4 This is a schematic diagram of the weld seam treatment mechanism of the present invention.

[0020] Figure 5 This is an exploded view of the weld seam treatment mechanism of the present invention.

[0021] Figure 6 This is a schematic diagram of the pretreatment mechanism of the present invention.

[0022] Figure 7 This is an exploded view of the pretreatment mechanism of the present invention.

[0023] Figure 8 This is a schematic diagram of the frame structure of the pretreatment mechanism of the present invention.

[0024] Figure 9 This is a schematic diagram of the grinding mechanism of the present invention.

[0025] Figure 10 This is a cross-sectional view of the grinding mechanism of the present invention.

[0026] Figure 11 This is an exploded view of the transmission mechanism of the present invention.

[0027] Figure 12 This is a schematic diagram of the structure of the grinding plate and the rotating cylinder of the present invention.

[0028] Figure 13 This is a schematic diagram of the drive mechanism of the present invention.

[0029] Figure 14 This is a schematic diagram of the connecting frame of the present invention.

[0030] Figure 15 This is a schematic diagram of the post-processing mechanism of the present invention.

[0031] Figure 16 This is a cross-sectional view of the post-processing mechanism of the present invention.

[0032] As shown in the figure: 01. Steel pipe; 1. Auxiliary conveying mechanism; 2. Weld seam treatment mechanism; 3. Pre-treatment mechanism; 4. Connecting frame; 5. Post-treatment mechanism; 6. Drive mechanism; 7. Grinding mechanism; 8. Spraying mechanism; 9. Welding slag cleaning mechanism; 11. Motor 1; 12. Gearbox; 13. Drive spindle; 14. Fixed seat; 15. Spiral conveyor table; 16. Magnetic seat; 31. Moving base frame; 32. Support frame; 33. Foot plate; 34. Roller; 35. Fixed plate; 36. Fixing mechanism; 361. Wing plate; 362. Arc plate; 363. Ball; 364. Positioning rod; 365. Spring; 41. Mounting plate; 42. Hydraulic cylinder; 43. Push plate; 51. Functional frame; 52. Stand Frame; 61. Motor II; 62. Drive Shaft I; 63. Bevel Gear I; 64. Bevel Gear II; 65. Drive Shaft II; 66. Bevel Gear III; 71. Adjusting Table; 72. Threaded Column; 73. Transmission Mechanism; 731. Transmission Shaft; 732. Splined Shaft; 733. Gear I; 734. Gear II; 735. Turntable; 736. Gear Ring; 737. Slot; 74. Grinding Head; 75. Grinding Plate; 76. Rotary Cylinder; 761. Clamping Table; 77. Connecting Rod; 78. Elastic Telescopic Rod; 81. Spray Box; 82. Feed Pipe; 83. Fixed Pipe; 84. Ball Table; 85. Turntable; 86. Spray Nozzle; 87. Rotating Cylinder; 88. Bevel Gear IV; 91. Negative Pressure Box; 92. Suction Table; 93. Air Duct. Detailed Implementation

[0033] The present invention will now be described in further detail with reference to the accompanying drawings.

[0034] Combined with appendix Figure 1 Appendix Figure 2 Appendix Figure 4 and attached Figure 5As shown, a grinding device for the inner weld of a large-diameter galvanized steel pipe includes an auxiliary conveying mechanism 1 and a weld treatment mechanism 2. The auxiliary conveying mechanism 1 rotates and conveys the steel pipe 01. The weld treatment mechanism 2 includes a pre-treatment mechanism 3, a connecting frame 4, and a post-treatment mechanism 5. The connecting frame 4 connects the pre-treatment mechanism 3 and the post-treatment mechanism 5. The pre-treatment mechanism 3 is equipped with a driving mechanism 6 and a grinding mechanism 7. The post-treatment mechanism 5 is equipped with a spraying mechanism 8 and a welding slag cleaning mechanism 9. The driving mechanism 6 drives the grinding mechanism 7 and the spraying mechanism 8 to grind and spray the spiral weld of the steel pipe 01. The welding slag cleaning mechanism 9 cleans the welding slag after grinding and before spraying.

[0035] This large-diameter galvanized steel pipe inner weld grinding device primarily addresses issues in traditional large-diameter galvanized steel pipe manufacturing, such as untimely weld treatment, uneven treatment quality, poor coordination between processes, and residual weld slag affecting subsequent processing. Traditionally, pipe manufacturing and weld treatment often require separate operations, leading to process disconnect. Furthermore, grinding, cleaning, and spraying are difficult to coordinate synchronously, increasing labor costs and resulting in incomplete grinding and uneven spraying coverage, impacting the corrosion resistance and overall quality of the inner end of the pipe. To address these issues, the device integrates the auxiliary conveying mechanism 1 and the weld treatment mechanism 2, achieving integrated operation of pipe auxiliary conveying and weld treatment. It also seamlessly connects pre-treatment grinding, weld slag cleaning, and post-treatment spraying processes, with unified drive mechanism 6 ensuring synchronized and precise actions at each stage. This effectively improves processing efficiency and quality, resolving the low efficiency issues caused by manual intervention.

[0036] Its working process closely revolves around the transportation of steel pipe 01 and the entire process of weld seam treatment. Various mechanisms work together to complete the operation. During the welding process, the conveying equipment rotates the steel pipe 01 and pushes it backward during the rotation. This device is located between the welding equipment and the cutting equipment. The auxiliary conveying mechanism 1 assists in transporting the steel pipe 01 to the cutting equipment position. During operation, the auxiliary conveying mechanism 1 is activated. This mechanism works with the welding conveying equipment to spirally transport the steel pipe 01. When the welding conveying equipment transports the steel pipe 01, considering that the welding position of the welding mechanism is fixed, the spiral weld seam remains unchanged during the spiral transport of the steel pipe 01. Therefore, the weld seam treatment mechanism 2 must also maintain a fixed position when treating the weld seam.

[0037] When the weld treatment mechanism 2 is working, the pre-treatment mechanism 3 takes the lead. Its drive mechanism 6 starts and drives the grinding mechanism 7. The grinding mechanism 7 precisely fits the spiral weld seam inside the steel pipe 01. As the steel pipe 01 rotates and the grinding mechanism 7 feeds, it thoroughly grinds the weld surface at the lowest position, removing protrusions, burrs, and surrounding oxide layers, laying a smooth foundation for subsequent spraying. After the pre-treatment mechanism 3 completes the grinding operation, the post-treatment mechanism 5 begins to intervene. The welding slag cleaning mechanism 9 specifically cleans the welding slag behind the treated weld area, thoroughly removing welding slag, dust, and other impurities generated during the grinding process through adsorption, blowing, and other methods. To avoid impurities affecting the adhesion and quality of the coating, after the welding slag is cleaned, the drive mechanism 6 synchronously drives the spraying mechanism 8 on the post-processing mechanism 5 to start. The spraying mechanism 8 sprays the anti-corrosion coating evenly and continuously onto the surface of the weld after grinding and cleaning, forming a dense anti-corrosion coating to prevent the steel pipe 01 from oxidizing and rusting before galvanizing. Throughout the entire process, the rotational conveying speed of the auxiliary conveying mechanism 1 is precisely matched with the working speed of the drive mechanism 6 driving the grinding and spraying mechanism 8 to ensure thorough grinding, cleaning, and uniform spraying, thus completing the high-quality treatment of the inner weld of the steel pipe 01. The treated steel pipe 01 is then transported to the next process by the auxiliary conveying mechanism 1.

[0038] Combined with appendix Figure 5 and attached Figure 6 As shown, the pretreatment mechanism 3 includes a movable base frame 31 that moves within the steel pipe 01. The top of the movable base frame 31 is provided with a height-adjustable support frame 32. The posttreatment mechanism 5 includes a functional frame 51. A connecting frame 4 connects the movable base frame 31 and the functional frame 51. The movable base frame 31, the support frame 32, and the functional frame 51 are all provided with foot plates 33. Multiple inclined rollers 34 are rotatably provided on the foot plates 33.

[0039] The pretreatment mechanism 3 provides an effective solution to the problems of poor flexibility, low positioning accuracy, weak adaptability to different pipe diameters, and insufficient operational stability of traditional weld treatment equipment when operating inside large-diameter steel pipes 01. The traditional weld treatment mechanism 2 cannot move stably inside the steel pipe 01, resulting in a large misalignment between the grinding mechanism 7 and the weld. It is also difficult to adjust the grinding height according to the inner diameter of the steel pipe 01. Special equipment needs to be replaced for steel pipes 01 of different diameters, which not only increases the operating cost but also reduces efficiency. At the same time, the mechanism is prone to shaking during the rotation and conveying of the steel pipe 01, which affects the grinding quality.

[0040] The pretreatment mechanism 3 includes a movable base frame 31 and an adjustable height support frame 32, which can form a suitable support inside the steel pipe 01. The foot plate 33 and the inclined rollers 34 on it can move spirally with the steel pipe 01, so that the entire pretreatment mechanism 3 can move smoothly inside the steel pipe 01 (relatively stationary with the auxiliary conveying mechanism 1), solving the problem of inconvenient movement of the mechanism inside the pipe. The support frame 32 can accurately adjust the height of the grinding mechanism 7 according to the actual inner diameter of the steel pipe 01, so that the grinding mechanism 7 always maintains the best fit with the weld, effectively improving the adaptability of the equipment to steel pipes 01 of different diameters. The multiple inclined rollers 34 on the foot plate 33 of the movable base frame 31, support frame 32 and posttreatment mechanism 5 functional frame 51 can form a stable contact with the inner wall of the steel pipe 01. The rotation of the rollers 34 assists the mechanism to rotate synchronously with the steel pipe 01, and also limits the shaking of the mechanism inside the pipe, ensuring the stability of the operation process and avoiding the problem of incomplete or over-grinding caused by the deviation of the mechanism.

[0041] Combined with appendix Figure 1 Appendix Figure 6 and attached Figure 7 As shown, the movable base 31 is symmetrically equipped with a fixing mechanism 36 at its front and rear ends. The fixing mechanism 36 includes a wing plate 361 mounted on the movable base 31, an arc plate 362 at the bottom of the wing plate 361, a magnet at the bottom of the arc plate 362, and multiple rolling balls 363 rotatably arranged in the ball groove at the bottom of the arc plate 362. A positioning rod 364 is provided at the top of the arc plate 362, which slides and engages with the through hole on the wing plate 361. A spring 365 is connected between the wing plate 361 and the arc plate 362. The movable base 31 is kept relatively stationary with the auxiliary conveying mechanism 1 by the magnetic cooperation between the fixing mechanism 36 and the auxiliary conveying mechanism 1.

[0042] Combined with appendix Figure 2 and attached Figure 3 As shown, the auxiliary conveying mechanism 1 includes a motor 11, a reduction gearbox 12, and a fixed base 14. A drive spindle 13 is symmetrically rotated on the fixed base 14. The output end of the motor 11 is connected to the reduction gearbox 12. The output end of the reduction gearbox 12 is connected to the drive spindle 13 via a sprocket structure. The drive spindle 13 is equipped with a spiral conveying table 15 that rotates in conjunction with the spiral of the steel pipe 01. A magnetic seat 16 is provided on the fixed base 14 at a corresponding position below the fixing mechanism 36. The magnetic seat 16 restricts the movement of the fixing mechanism 36 by magnetic force.

[0043] The stabilizing mechanism 36, in conjunction with the auxiliary conveying mechanism 1, provides a reliable foundation for maintaining the stable position of this device inside the spirally moving steel pipe 01. This specifically addresses key issues in traditional steel pipe 01 processing equipment, such as unstable positioning, large mechanism positioning deviations, and asynchronous movements between the in-pipe working mechanism and the conveying system. Regarding mechanism positioning, when the pre-treatment mechanism 3 operates inside the steel pipe 01, it is easily affected by the rotational inertia of the steel pipe 01 and the grinding reaction force, causing it to rotate synchronously with the steel pipe 01 or experience axial displacement. This leads to the failure of the grinding mechanism 7 to align with the weld, resulting in grinding leaks or over-grinding.

[0044] The positioning mechanism 36 works in close coordination with the auxiliary conveying mechanism 1, forming a complete closed loop of "stable conveying - precise positioning - operational support". Before the operation starts, the steel pipe 01 is conveyed to the spiral conveyor table 15 of the auxiliary conveying mechanism 1 via the welding conveying equipment. At this time, the motor 11 of the auxiliary conveying mechanism 1 starts to run. Its output power is adjusted by the speed reduction gearbox 12 and then the torque is transmitted to the drive spindle 13 symmetrically arranged on the fixed seat 14 through the sprocket structure. The drive spindle 13 drives the spiral conveyor table 15 to rotate synchronously. The spiral surface of the spiral conveyor table 15 is in contact with the outer wall of the steel pipe 01, which facilitates the rotational conveying of the steel pipe 01 and ensures the stability of the steel pipe 01 when the conveying path is extended. The weld treatment mechanism 2 is placed in advance in the pipe above the fixed seat 14 with the magnetic seat 16. When the magnetic base 16 below 36 is energized, it generates a stable magnetic force that attracts the arc plate 362. This force interacts with the magnet at the bottom of the arc plate 362, causing the arc plate 362 to adhere tightly to the steel pipe 01. As the steel pipe 01 moves spirally, the moving base 31 of the pretreatment mechanism 3 begins to move relative to the inner wall of the steel pipe 01 (the steel pipe 01 moves spirally, while the position of the weld treatment mechanism 2 remains unchanged). The fixing mechanism 36 moves synchronously with the moving base 31. At this time, the ball 363 at the bottom of the arc plate 362 contacts the inner wall of the steel pipe 01, converting sliding friction into rolling friction, significantly reducing the moving resistance and ensuring a smooth and stable movement. The positioning rod 364 slides along the through hole on the wing plate 361, providing vertical guidance for the arc plate 362. Together with the spring 365, this allows the arc plate 362 to adapt to the slight undulations of the inner wall of the steel pipe 01. Combined with appendix Figure 14 As shown, the connecting frame 4 is provided with a mounting plate 41, and multiple hydraulic cylinders 42 are inclinedly provided on the mounting plate 41. A push plate 43 is hinged to the output end of the hydraulic cylinder 42.

[0045] To address potential positional shifts in the weld treatment mechanism 2, when a misalignment is detected between the working position of the grinding mechanism 7 and the weld position (monitored in real-time by the visual inspection system), the hydraulic cylinder 42 on the mounting plate 41 is activated, pushing the push plate 43 closer to the steel pipe 01. The reaction force of the steel pipe 01 on the push plate 43 pushes the weld treatment mechanism 2 forward, causing the working position of the grinding mechanism 7 to return to the weld position. Within the allowable range of the welding equipment's working space, a pull rope can be installed at the front end of the movable base frame 31 to maintain the stability of the weld treatment mechanism 2's position. The design of the push plate 43 and the fixing mechanism 36 in this device is an option chosen when external assistance is unavailable.

[0046] Combined with appendix Figure 8 and attached Figure 9 As shown, the grinding mechanism 7 includes an adjustment table 71, a transmission shaft 731, a grinding head 74, and a grinding plate 75. The adjustment table 71 has a threaded post 72 on its side, and a fixed plate 35 is provided on the movable base 31. The threaded post 72 passes through the through hole on the fixed plate 35 and is fixed in position by double nuts. The transmission mechanism 73 is rotatably mounted on the adjustment table 71 and is connected to the drive mechanism 6. The transmission mechanism 73 drives the grinding head 74 and the grinding plate 75 to rotate synchronously.

[0047] Combined with appendix Figure 10 and attached Figure 11 As shown, the transmission mechanism 73 includes a transmission shaft 731, a second gear 734, and a turntable 735. The transmission shaft 731 is connected to the drive mechanism 6. The bottom of the transmission shaft 731 is connected to the grinding head 74. The second gear 734 and the turntable 735 are rotatably disposed inside the adjustment table 71. The transmission shaft 731 is provided with a first gear 733 that meshes with the second gear 734. The inner side of the turntable 735 is provided with a toothed ring 736 that meshes with the second gear 734.

[0048] As the core component for pre-treatment of the inner weld seam of large-diameter galvanized steel pipes, the grinding mechanism 7 specifically addresses the problems of low grinding precision, inconvenient feed adjustment, limited weld seam treatment options, and low power transmission efficiency found in traditional grinding equipment. Traditional grinding mechanisms 7, with their single grinding component, can only handle surface protrusions of the weld seam, failing to address the fine finishing of the weld seam edges. This often results in incomplete grinding or damage to the inner wall of the steel pipe 01. Furthermore, the simple power transmission structure is prone to transmission jamming, affecting grinding stability.

[0049] The working process of the grinding mechanism 7 is precisely coordinated with the actions of the auxiliary conveying mechanism 1 and the fixing mechanism 36 to form an efficient "positioning-adjustment-grinding" operation process. Before operation, the grinding mechanism 7 first performs position calibration: according to the actual height and position of the spiral weld seam inside the steel pipe 01, the double nuts of the fixed threaded column 72 on the fixing plate 35 are loosened, and the adjusting table 71 is pushed to move horizontally so that the grinding head 74 and the grinding plate 75 are aligned with the weld seam area; then the drive mechanism 6 is started, transmitting power to the drive shaft 731 of the grinding mechanism 7. The drive shaft 731 starts to rotate at high speed and drives the gear 733 on it to rotate synchronously. The gear 733 meshes with the gear 734 inside the adjusting table 71, causing the gear 734 to rotate accordingly. Through the meshing of the gear 734 with the gear ring 736 on the inner side of the turntable 735, the turntable 735 is driven to rotate smoothly.

[0050] During this transmission process, the grinding head 74 connected to the bottom of the drive shaft 731 rotates directly with the drive shaft 731, while the grinding plate 75 mounted on the turntable 735 rotates synchronously with the turntable 735. Through the precise coordination of the two-stage transmission structure, the synchronous rotation of the grinding head 74 and the grinding plate 75 is achieved, ensuring consistent grinding actions. During the grinding operation, the steel pipe 01 rotates at a uniform speed under the drive of the spiral conveyor table 15 of the auxiliary conveying mechanism 1. The grinding head 74 first performs powerful grinding on the protrusions and weld beads on the weld surface, quickly removing obvious defects at the weld. At the same time, the grinding plate 75 is close to the edge of the weld, finely grinding the surface of the weld and the edge burrs after grinding, smoothing the weld surface to a flat and smooth finish. Through the two-stage transmission structure, the design requirement of the grinding head 74 and the grinding plate 75 rotating in opposite directions is achieved. This design solves the problem of uneven power output and speed fluctuation in the traditional single transmission method, ensuring synchronous operation of both and improving grinding quality and efficiency.

[0051] The design of the grinding head 74 and the grinding plate 75 rotating in opposite directions firstly creates opposing grinding forces, balancing the grinding forces on the weld and surrounding area. This reduces vibration of the grinding mechanism 7 caused by unidirectional forces. Combined with the positioning effect of the retaining mechanism 36, this further enhances overall operational stability and prevents grinding depth deviations caused by vibration. Secondly, the reverse rotation allows the grinding head 74 to powerfully grind the weld protrusions while the grinding plate 75 immediately smooths the burrs and rough surfaces generated during grinding, creating a continuous "grinding-smoothing" operation. This prevents weld chips from accumulating in the weld area, improving grinding efficiency while ensuring a smooth weld surface. Furthermore, the reverse rotation expands the effective grinding coverage area. The grinding head 74 focuses on the core protrusions of the weld, while the grinding plate 75 covers the weld edges with a reverse trajectory, reducing grinding dead angles. Especially for the continuous curve shape of spiral welds, the reverse rotation allows for closer contact between both parts and the weld, adapting to changes in weld direction and improving grinding uniformity.

[0052] Combined with appendix Figure 12 As shown, the bottom of the adjustment table 71 is provided with a rotating cylinder 76, the top of the rotating cylinder 76 is provided with a locking platform 761, the bottom of the turntable 735 is provided with a locking groove 737 that is inserted and matched with the locking platform 761, the bottom of the rotating cylinder 76 is provided with multiple connecting rods 77, the grinding plate 75 is hinged to the other end of the connecting rod 77, and an elastic telescopic rod 78 is hinged between the connecting rod 77 and the outer side of the rotating cylinder 76.

[0053] As the core component for pre-treatment of the inner weld seam of large-diameter galvanized steel pipes, the grinding mechanism 7 has been further optimized based on the original improvements, addressing issues such as the difficulty of adapting traditional grinding equipment to the inner arc surface of steel pipe 01, poor fit of arc weld seam grinding, and incomplete local grinding. Traditional grinding mechanisms 7 often have a fixed-angle design for the grinding plate 75, which cannot flexibly adjust its posture to follow the arc contour of the inner wall of steel pipe 01. For curved weld seams on the inner edge of large-diameter steel pipe 01, the grinding plate 75 often does not fit tightly against the weld surface, resulting in grinding dead corners in the arc area.

[0054] During the grinding operation, when the grinding plate 75 moves to different arc-shaped positions inside the steel pipe 01, its hinge structure with the bottom of the rotating cylinder 76 allows the grinding plate 75 to swing flexibly to adjust its angle. If it encounters a convex part of the arc surface, the grinding plate 75 pushes the connecting rod 77 to rotate around the hinge point, thereby compressing the corresponding elastic telescopic rod 78. The elastic telescopic rod 78 generates a reverse elastic force, ensuring that the grinding plate 75 is tightly pressed against the convex part of the arc surface. When the grinding plate 75 moves to a concave part of the arc surface, the elastic telescopic rod 78 extends, pushing the connecting rod 77 to drive the grinding plate 75 to swing outward, always keeping it in contact with the concave area, achieving adaptive following of the arc surface. The continuous elastic force of the elastic telescopic rod 78 provides the grinding plate 75 with stable grinding pressure, avoiding uneven grinding depth of the arc surface due to uneven pressure.

[0055] Combined with appendix Figure 5 Appendix Figure 8 Appendix Figure 9 Appendix Figure 11 and attached Figure 13 As shown, the drive mechanism 6 includes a second motor 61, a first drive shaft 62, and a second drive shaft 65. The second motor 61 is fixed on the movable base 31. The first drive shaft 62 is rotatably mounted on the movable base 31 and the post-processing mechanism 5. The second drive shaft 65 is rotatably mounted on the fixed plate 35. The output end of the second motor 61 is connected to the first drive shaft 62. The first drive shaft 62 is provided with a first bevel gear 63. The second drive shaft 65 is provided with a third bevel gear 66 that meshes with the first bevel gear 63. The top of the transmission shaft 731 is provided with a spline shaft 732. The bottom of the second drive shaft 65 is provided with a spline groove that mates with the spline shaft 732.

[0056] As the power core of the grinding mechanism 7, the drive mechanism 6 has been optimized and upgraded through a brand-new structural design to address the problems of traditional drive devices, such as single power transmission direction, poor adaptability to the position adjustment of the grinding mechanism 7, low transmission accuracy, and large power loss. The traditional drive mechanism 6 often adopts a direct drive method. When the grinding mechanism 7 needs to be adjusted to adapt to different pipe diameters, it is easy to cause the transmission structure to disengage or jam. Moreover, the power transmission direction is fixed, which makes it difficult to meet the multi-directional power needs of the grinding mechanism 7. At the same time, the simple transmission structure is prone to unstable power output, which affects the grinding quality.

[0057] The working process of the drive mechanism 6 is closely coordinated with the mobile base 31, the grinding mechanism 7, and the fixing mechanism 36 to form a complete power chain of "power output - direction conversion - precise transmission - operation drive". During operation, the second motor 61, fixed on the mobile base 31, starts after being powered on. Its output end directly drives the first drive shaft 62 to rotate. The first drive shaft 62 rotates smoothly under the support of the mobile base 31 and the post-processing mechanism 5, transmitting the power of the second motor 61 in the horizontal direction. When the power is transmitted to the first bevel gear 63 on the first drive shaft 62, the vertical conversion of the power transmission direction is achieved through the meshing of the first bevel gear 63 and the third bevel gear 66 on the second drive shaft 65, converting the horizontal rotation of the first drive shaft 62 into a driving direction. The vertical rotation of the second drive shaft 65 causes the second drive shaft 65 to operate stably under the support of the fixed plate 35. At this time, the spline groove at the bottom of the second drive shaft 65 is tightly engaged with the spline shaft 732 at the top of the transmission shaft 731. Due to the axial movement characteristic of the spline structure, even if the grinding mechanism 7 adjusts the position through the threaded column 72, causing the transmission shaft 731 to undergo axial displacement, the spline shaft 732 can still maintain stable engagement with the spline groove, ensuring that the power is transmitted to the transmission shaft 731 without interruption. The transmission shaft 731 rotates at high speed under the power drive, and then through the two-stage transmission of gear 1 733, gear 2 734 and gear ring 736, it drives the grinding head 74 and the grinding plate 75 to rotate synchronously in opposite directions, realizing the grinding of the weld and the arc surface grinding operation.

[0058] Combined with appendix Figure 15 and attached Figure 16 As shown, the spraying mechanism 8 includes a spraying box 81, a turntable 85, and a rotating cylinder 87. The spraying box 81 is mounted on a functional frame 51, and a support frame 52 is mounted on the functional frame 51. The rotating cylinder 76 is rotatably mounted on the support frame 52. The bottom of the rotating cylinder 87 is provided with a bevel gear 88, and the end of the drive shaft 62 is provided with a bevel gear 64 that meshes with the bevel gear 88. The turntable 85 is mounted on the top of the rotating cylinder 87, and a spray head 86 is provided on the turntable 85. The spraying box 81 supplies material to the spray head 86.

[0059] Combined with appendix Figure 16As shown, the rotating cylinder 87 is provided with a fixed tube 83, which is connected to the functional frame 51. One end of the fixed tube 83 is connected to the feeder inside the spray box 81 through the feed tube 82, and the other end is provided with a ball table 84 that rotates with the ball groove at the bottom of the turntable 85. The internal channel of the ball table 84 is connected to the turntable 85 and the fixed tube 83.

[0060] As a key component in weld post-treatment, the spraying mechanism 8 addresses the problems of interference between the feeding and rotation actions of traditional spraying equipment, the inability of the fixed spraying angle to adapt to the inner arc surface of the steel pipe 01, high energy consumption due to separate power configuration, and asynchronous actions through innovative structural design. Traditional spraying mechanisms 8 often directly connect the feeding pipe 82 to the rotating component, which can easily cause the pipe to entangle and break during rotation. In addition, the fixed angle of the nozzle 86 makes it difficult to uniformly spray the arc-shaped weld seam inside the steel pipe 01. Furthermore, a separate drive device is required, which not only increases equipment costs but also easily leads to asynchronous actions with the preceding grinding action, affecting the coating quality.

[0061] The working process of the spraying mechanism 8 is closely integrated with the drive mechanism 6, the auxiliary conveying mechanism 1, and the welding slag cleaning mechanism 9, forming an efficient operation process of "power sharing - material supply guarantee - angle adaptation - precise spraying". The spraying mechanism 8 remains relatively stationary with the functional frame 51 and the moving base frame 31. The fixing mechanism 36 is continuously positioned by the magnetic seat 16 to ensure the stability of the overall structure, so that the spraying area of ​​the spraying mechanism 8 is stably aligned with the weld seam area at the top. The motor 61 of the drive mechanism 6 runs continuously, driving the drive shaft 62 to rotate. The bevel gear 64 at the end of the drive shaft 62 meshes with the bevel gear 88 at the bottom of the rotating cylinder 87, transmitting power to the rotating cylinder 87. Supported by the functional frame 51 and the upright frame 52, the device rotates smoothly, which in turn drives the turntable 85 mounted on the top to rotate synchronously. The nozzles 86 on the turntable 85 begin to move in a circular motion with the turntable 85. At the same time, the feeder in the spray box 81 is activated, and the paint is transported through the feed pipe 82 to the fixed pipe 83 which is fixedly connected to the functional frame 51. The paint in the fixed pipe 83 flows into the turntable 85 through the internal channel of the ball joint 84 at its end, and is then distributed by the turntable 85 to each nozzle 86 to achieve a stable supply of paint. With the rotation and transport of the steel pipe 01 and the circular motion of the nozzles 86, the nozzles 86 spray the paint in an atomized state evenly on the weld and surrounding area to form a continuous, dense, and thin anti-corrosion coating.

[0062] Combined with appendix Figure 15 and attached Figure 16 As shown, the welding slag cleaning mechanism 9 includes a negative pressure box 91 and a suction table 92. Both the negative pressure box 91 and the suction table 92 are fixed on the functional frame 51. The suction table 92 is connected to the fan inside the negative pressure box 91 through the air duct 93.

[0063] As a key transitional component between the grinding and spraying processes, the welding slag cleaning mechanism 9 specifically addresses the problems of traditional welding slag residue remaining in the pipeline after cleaning, affecting spraying quality, and secondary pollution during the spiral conveying of steel pipe 01. Traditionally, welding slag is mostly removed manually by blowing or simply brushing after grinding. For the inner space of large-diameter steel pipe 01, cleaning is quite laborious. These residual welding slags can cause defects such as bubbles and pinholes in the coating during subsequent spraying, affecting the anti-corrosion effect. At the same time, manual cleaning is inefficient and can easily cause welding slag to scatter to other areas of steel pipe 01, causing secondary pollution.

[0064] The welding slag cleaning mechanism 9 works in precise coordination with the pretreatment grinding mechanism 7, the auxiliary conveying mechanism 1, and the subsequent spraying mechanism 8 to form a continuous "grinding-cleaning-spraying" operation chain, ensuring the cleanliness of the weld area. After grinding, the weld is gradually moved to the top by the spiral conveyor of the steel pipe 01, while the grinding slag and excess welding material accumulate at the bottom of the pipe and enter the working range of the welding slag cleaning mechanism 9 as the pipe moves backward. At this time, the moving base 31 remains relatively stationary with the magnetic seat 16 of the auxiliary conveying mechanism 1 through the fixing mechanism 36, and the suction table... 92 is fixed in place with the functional frame 51. Its suction port has been pre-adjusted to a suitable position to fit the weld surface to ensure the adsorption effect. During operation, the fan inside the negative pressure box 91 starts. The strong negative pressure generated by the fan is quickly transmitted to the suction table 92 through the air duct 93, so that the suction port of the suction table 92 forms a stable negative pressure field. When the weld area with welding shavings and dust passes through the suction table 92, the welding shavings and dust are attracted by the negative pressure and enter the air duct 93 through the suction port of the suction table 92. Then, the air duct 93 transports them into the negative pressure box 91 to complete the collection and cleaning of welding shavings.

[0065] The present invention and its embodiments have been described above. This description is not restrictive, and the accompanying drawings are only one embodiment of the present invention; the actual structure is not limited thereto. In conclusion, if those skilled in the art are inspired by this description and design similar structures and embodiments without departing from the spirit of the invention, such designs should fall within the protection scope of the present invention.

Claims

1. A large-diameter galvanized steel pipe inner mouth weld polishing device, comprising an auxiliary conveying mechanism (1) and a weld processing mechanism (2), the auxiliary conveying mechanism (1) rotates and conveys the steel pipe (01), characterized in that: the weld processing mechanism (2) comprises a front processing mechanism (3), a connecting frame (4) and a rear processing mechanism (5), the front processing mechanism (3) is provided with a driving mechanism (6) and a polishing mechanism (7), the rear processing mechanism (5) is provided with a spraying mechanism (8), the driving mechanism (6) drives the polishing mechanism (7) and the spraying mechanism (8) to polish and spray the spiral weld of the steel pipe (01); the front processing mechanism (3) comprises a mobile chassis (31) moving in the steel pipe (01), the mobile chassis (31) remains relatively stationary with the auxiliary conveying mechanism (1), the rear processing mechanism (5) comprises a functional frame (51), and the connecting frame (4) connects the mobile chassis (31) and the functional frame (51) front and back; the polishing mechanism (7) comprises an adjusting table (71), a transmission mechanism (73), a grinding head (74) and a polishing plate (75), the adjusting table (71) is adjustably mounted on the mobile chassis (31), the transmission mechanism (73) is rotatably provided on the adjusting table (71) and is in transmission connection with the driving mechanism (6), and the transmission mechanism (73) drives the grinding head (74) and the polishing plate (75) to rotate synchronously.

2. A device for grinding the inner weld of a large-diameter galvanized steel pipe according to claim 1, characterized in that: the transmission mechanism (73) comprises a transmission shaft (731), a gear two (734) and a rotating disc (735), the transmission shaft (731) is in transmission connection with the driving mechanism (6), the bottom of the transmission shaft (731) is connected with the grinding head (74), the bottom of the adjusting table (71) is rotatably provided with a rotating cylinder (76), a plurality of connecting rods (77) are hingedly arranged at the bottom of the rotating cylinder (76), the polishing plate (75) is hingedly arranged at the other end of the connecting rods (77), and elastic telescopic rods (78) are hingedly arranged between the connecting rods (77) and the outer side of the rotating cylinder (76); the gear two (734) and the rotating disc (735) are rotatably arranged inside the adjusting table (71), the transmission shaft (731) is provided with a gear one (733) engaged with the gear two (734), and the inner side of the rotating disc (735) is provided with a gear ring (736) engaged with the gear two (734).

3. A device for grinding the inside weld of a large diameter galvanized steel pipe according to claim 2, characterized in that: the transmission mechanism (73) further comprises the gear two (734) and the rotating disc (735), the bottom of the adjusting table (71) is rotatably provided with the rotating cylinder (76), the gear two (734) and the rotating disc (735) are rotatably arranged inside the adjusting table (71), the transmission shaft (731) is provided with the gear one (733) engaged with the gear two (734), the inner side of the rotating disc (735) is provided with the gear ring (736) engaged with the gear two (734), the top of the rotating cylinder (76) is provided with a clamping table (761), the inside of the rotating disc (735) is provided with a clamping groove (737) matched with the clamping table (761) in plug-in mode, the bottom of the rotating cylinder (76) is hingedly provided with the plurality of connecting rods (77), the polishing plate (75) is hingedly arranged at the other end of the connecting rods (77), and the elastic telescopic rods (78) are hingedly arranged between the connecting rods (77) and the outer side of the rotating cylinder (76).

4. A device for grinding the inner weld of a large-diameter galvanized steel pipe according to claim 2, characterized in that: The driving mechanism (6) comprises a second motor (61), a first driving shaft (62) and a second driving shaft (65), the second motor (61) is fixed on the mobile chassis (31), the first driving shaft (62) is rotatably arranged on the mobile chassis (31) and the post-processing mechanism (5), the second driving shaft (65) is rotatably arranged on the mobile chassis (31), the output end of the second motor (61) is connected with the first driving shaft (62), the first driving shaft (62) is provided with a bevel gear (63), the second driving shaft (65) is provided with a bevel gear (66) engaged with the bevel gear (63), the top of the transmission shaft (731) is provided with a spline shaft (732), and the bottom of the second driving shaft (65) is provided with a spline groove matched with the spline shaft (732).

5. A device for grinding the inside weld of a large diameter galvanized steel pipe according to claim 4, characterized in that: The spraying mechanism (8) comprises a spraying box (81), a rotary table (85) and a transmission cylinder (87), the spraying box (81) is arranged on the functional frame (51), the functional frame (51) is provided with a stand (52), the transmission cylinder (87) is rotatably arranged on the stand (52), the bottom of the transmission cylinder (87) is provided with a bevel gear (88), the end of the first driving shaft (62) is provided with a bevel gear (64) engaged with the bevel gear (88), the rotary table (85) is installed on the top of the transmission cylinder (87), the rotary table (85) is provided with a spray head (86), and the spraying box (81) supplies material for the spray head (86).

6. A device for grinding the inside weld of a large diameter galvanized steel pipe according to claim 5, characterized in that: The transmission cylinder (87) is provided with a fixed pipe (83), the fixed pipe (83) is connected with the functional frame (51), one end of the fixed pipe (83) is connected with an internal material supplier of the spraying box (81) through a material supply pipe (82), and the other end is provided with a ball table (84) rotatably matched with the bottom ball groove of the rotary table (85), and the internal passage of the ball table (84) is communicated with the rotary table (85) and the fixed pipe (83).

7. A device for grinding the inside weld of a large diameter galvanized pipe according to claim 1, characterized in that: The top of the mobile chassis (31) is provided with an adjustable height support frame (32), the mobile chassis (31), the support frame (32) and the functional frame (51) are all provided with foot plates (33), and a plurality of inclined rollers (34) are rotatably arranged on the foot plates (33).

8. A device for grinding the inside weld of a large diameter galvanized pipe according to claim 1, characterized in that: The connecting frame (4) is provided with a mounting plate (41), a plurality of hydraulic cylinders (42) are inclinedly arranged on the mounting plate (41), and a push plate (43) is hingedly arranged at the output end of the hydraulic cylinder (42).

9. A device for grinding the inside weld of a large diameter galvanized pipe according to claim 1, characterized in that: The functional frame (51) is provided with a welding slag cleaning mechanism (9), the welding slag cleaning mechanism (9) comprises a negative pressure box (91) and a material suction table (92), the negative pressure box (91) and the material suction table (92) are both fixed on the functional frame (51), and the material suction table (92) is connected with an internal fan of the negative pressure box (91) through an air pipe (93).

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