A longitudinal seam welding apparatus

Abstract

The application discloses a longitudinal seam welding device and relates to the technical field of pipeline welding. The device comprises a base, a reference plate arranged on the base, a welding device, a rotating device, a jacking device and an adjusting device. The rotating device is used for receiving a workpiece to be welded. The jacking device is provided with a liftable positioning column on a lifting plate, the inside of the positioning column is a cavity and is filled with a cooling medium, a mounting groove and a welding groove are formed in the side wall of the positioning column, and a light curtain area sensor is arranged in the mounting groove. The adjusting device can drive the positioning column to translate and rotate. During work, the positioning column is inserted into the workpiece, automatic optical centering of a weld is realized through cooperation of the sensor and the rotating device, then the positioning column abuts against the workpiece and welding is performed. The inside cooling medium can effectively control the temperature of a welding area, solves the welding quality fluctuation problem caused by heat accumulation of the positioning column, and simultaneously realizes high-precision and high-efficiency automatic centering and welding of heavy workpieces.

Description

Technical Field

[0001] This application relates to the field of pipeline welding technology, and in particular to a longitudinal seam welding device. Background Technology

[0002] In the field of pipeline manufacturing, valves, pipes, pressure vessel sections, and other workpieces are often made by rolling metal sheets. Specifically, a rectangular metal sheet is bent so that its first and last edges are opposite each other but not closed, thus forming a cylindrical workpiece with a longitudinal seam. This longitudinal seam is the weld that needs to be welded.

[0003] In longitudinal welds on valves, pipes, pressure vessel sections, and other workpieces, it is typically necessary to hold the workpiece against a reference surface, such as a platform or another workpiece, for fixation and positioning. Existing technologies generally employ rigid metal positioning posts or clamping blocks to perform this function. However, in actual continuous operations, this technical solution has the following significant drawbacks: 1. Regarding the issue of heat accumulation on the positioning posts During welding, the metal locating post needs to be continuously pressed against the workpiece, thus being directly exposed to the high-temperature radiation zone of the welding arc and continuously absorbing heat from the heated workpiece through conduction. Since the locating post is usually a solid metal structure with limited heat capacity and poor heat dissipation, the temperature will rise sharply when welding multiple workpieces consecutively.

[0004] This heat accumulation phenomenon leads to a series of process fluctuations: First, the high-temperature locating post acts as an unintended heat source, preheating the local contact area of ​​subsequently clamped workpieces and altering the initial temperature conditions at the welding start point. Second, welding process parameters such as current, voltage, and speed are usually set based on room-temperature fixtures, and changes in the temperature of the locating post directly interfere with the stability of the actual heat input and cooling rate during welding. As a result, in the same batch of work, the weld thermal cycle process differs between workpieces welded earlier and later, which may lead to inconsistencies in the weld metal microstructure, mechanical properties such as hardness, toughness, and residual stress distribution, severely affecting the uniformity and reliability of product quality.

[0005] 2. Regarding the efficiency and accuracy of weld calibration For the assembly and calibration of the aforementioned longitudinal welds, existing technologies primarily rely on manual adjustment. Operators need to manually rotate or translate the workpiece to align the edge to be welded with the reference surface. When the workpiece is heavy, manual operation is extremely laborious, slow, and poses safety hazards. More importantly, manual adjustment depends entirely on the operator's experience and visual inspection, making it difficult to achieve precise and repeatable positioning, especially in ensuring precise control of critical assembly dimensions such as misalignment. This inefficient and low-precision calibration method has become a key bottleneck restricting the improvement of cycle time and process digitization in automated welding production lines.

[0006] In summary, existing longitudinal welding technology for valves and pipelines suffers from two major contradictions: First, the rigid clamping components necessary to ensure positioning accuracy, due to the lack of effective thermal management design, become the main variable disrupting the stability and batch consistency of the welding process; second, reliance on manual calibration methods cannot meet the modern manufacturing requirements of assembly accuracy and operational efficiency for heavy and large workpieces. Therefore, there is an urgent need for a longitudinal seam welding device and method for valves and pipelines that can achieve active thermal control and possess high-precision automatic alignment capabilities to overcome these shortcomings. Summary of the Invention

[0007] To address the aforementioned problems, this application provides a longitudinal seam welding device.

[0008] A longitudinal seam welding device includes a base, a reference plate longitudinally fixed on the base, a welding device disposed on one side of the reference plate, a rotating device disposed on the other side of the reference plate and including a rotating table, a lifting device disposed on the base and including a liftable lifting plate and a positioning column, and an adjusting device disposed on the lifting plate for driving the positioning column to translate and rotate. The welding device is used to perform welding operations along the length direction of the reference plate, and the positioning column is used to extend into and abut against the workpiece to be welded.

[0009] This equipment integrates lifting, rotation, adjustment, and welding functions. By driving the positioning column through the adjustment device, and in conjunction with the rotary table, it can automatically center and clamp workpieces such as valves and pipes, replacing the inefficient, laborious, and inaccurate manual calibration method, thus laying the foundation for automated welding.

[0010] Furthermore, the positioning column has a sealed cavity inside, which is filled with a cooling medium.

[0011] The cooling medium can effectively absorb and remove the heat transferred to the positioning column during the welding process, preventing the positioning column from accumulating and rising in temperature due to continuous operation. This avoids the positioning column being used as a heat source to preheat subsequent workpieces, thereby ensuring the consistency of the welding start temperature conditions for workpieces in the same batch and improving the uniformity and reliability of the weld quality.

[0012] Furthermore, the side wall of the positioning column is provided with an installation groove, and a light curtain area sensor is installed in the installation groove.

[0013] The light curtain area sensor integrated on the positioning column can detect the light-transmitting area. In conjunction with the supplementary light, it can determine in real time and accurately whether the workpiece gap is aligned with the welding reference, realizing automated, high-precision visual inspection and centering of the weld position.

[0014] Furthermore, the side wall of the positioning post is also provided with a welding groove, which is recessed toward the axis of the positioning post.

[0015] During the final welding process, the recessed welding groove provides space for the excess height on the back of the weld, preventing the positioning post body from directly pressing on the hot and uncooled weld, thus preventing the weld formation from being damaged and ensuring the internal quality and appearance of the welded joint.

[0016] Furthermore, the adjustment device includes: a movable seat on which the positioning column is rotatably mounted; a translation mechanism connected to the movable seat for driving the movable seat and the positioning column to translate in the horizontal direction; and a rotation mechanism connected to the positioning column for driving the positioning column to rotate around its own axis.

[0017] The combination of translation and rotation mechanisms enables the positioning column to perform precise translation and rotation in the horizontal plane, thereby flexibly executing a series of complex actions such as initial clamping, retraction rotation alignment, and re-clamping. It is the key actuator for realizing automated centering and clamping processes.

[0018] Furthermore, the lifting plate is provided with an elongated adjustment groove, the positioning column passes through the adjustment groove, and the translation mechanism drives the positioning column to move along the length direction of the adjustment groove.

[0019] The adjusting groove provides precise guidance and stroke limitation for the translational movement of the positioning column, ensuring the straightness and stability of the movement trajectory of the positioning column when it is pressed against the workpiece, thereby improving the positioning accuracy and the reliability of equipment operation.

[0020] Furthermore, the welding device includes: a mounting plate whose length direction is parallel to the reference plate; a sliding pair arranged along the length direction of the mounting plate; a circumferential plate connected to the slider of the sliding pair; a feed drive mechanism for driving the circumferential plate to move along the sliding pair; and a welding gun mounted on the circumferential plate via a multi-directional adjustment mechanism.

[0021] The welding torch is mounted on a sliding pair via a ring plate and is driven by a feed drive mechanism to make a stable linear feed motion. With the help of a multi-directional adjustment mechanism, the welding torch can be precisely positioned and oriented in three-dimensional space, ensuring accurate welding path and optimal torch angle, thereby obtaining high-quality continuous welds.

[0022] Furthermore, the feed drive mechanism includes a rack fixed to the mounting plate, a motor mounted on the circumferential plate, and a gear driven by the motor and meshing with the rack.

[0023] The meshing transmission method of gears and racks has the advantages of compact structure, smooth transmission, high precision and large load-bearing capacity. It can ensure that the feeding speed of the welding gun is uniform and slip-free during long-distance welding, thus ensuring the stability of the welding process and the uniformity of weld formation.

[0024] Furthermore, the reference plate is provided with at least two rows of heat insulation sheets, and a gap for welding is formed between the at least two rows of heat insulation sheets.

[0025] The welding gap formed by the heat insulation sheet provides a channel for the welding torch. At the same time, the heat insulation sheet itself can effectively block the high temperature of welding from being directly transmitted to the main body of the reference plate, reducing the thermal deformation of the reference plate and protecting the accuracy and stability of the equipment foundation structure.

[0026] Furthermore, the heat insulation sheet is independently fixed to the reference plate by screws, and the width of the gap can be adjusted by adjusting the screws.

[0027] The independently adjustable heat insulation plate design allows the width of the welding gap to be flexibly and precisely adjusted according to the wall thickness, bevel type or welding process requirements of different workpieces, enhancing the process adaptability and versatility of the equipment.

[0028] In summary, this application includes at least one of the following beneficial technical effects: 1. By integrating light curtain area sensors and a rotating device, automated and high-precision visual alignment of longitudinal weld seams in heavy-duty pipelines is achieved, replacing inefficient, laborious, and experience-dependent manual calibration, thus improving production efficiency and positioning accuracy.

[0029] 2. By adopting a cavity structure positioning column with internal cooling medium, the problem of heat accumulation in continuous welding of traditional solid positioning columns is effectively solved, the initial temperature of the workpiece welding area is stabilized, and the consistency and reliability of weld quality of products in the same batch are guaranteed; in addition, the cooling medium prevents the temperature of the positioning column from becoming too high, making it possible to set electronic components on the positioning column.

[0030] 3. By adjusting the positioning column to perform a combined translation and rotation motion, and combining it with a reference plate with adjustable heat insulation sheet and a welding device with stable feed, a complete automated longitudinal seam welding solution is formed, realizing full-process automation and precise control from centering and clamping to welding. Attached Figure Description

[0031] Figure 1 It is a three-dimensional view of the equipment, mainly showing its overall structure; Figure 2 It is a three-dimensional view of the equipment from another perspective, mainly showing its overall structure; Figure 3 It is a partial view of the equipment, mainly showing the specific structure on the mounting plate, such as the feed motor and rack; Figure 4 This is a partial view of the equipment, mainly showing the welding mechanism; Figure 5 This is a partial view of the equipment, mainly showing the rotating mechanism; Figure 6 This is a partial view of the equipment, mainly showing the specific structure of the reference plate; Figure 7 This is a partial view of the equipment, mainly showing the adjustment mechanism; Figure 8 This is a partial view of the equipment, mainly showing the positioning posts.

[0032] Explanation of reference numerals in the attached drawings: 11. Moving seat; 12. Mounting hole; 13. Track; 14. Translation cylinder; 15. Rotary motor; 21. Lifting plate; 22. Positioning column; 23. Mounting slot; 24. Light curtain area sensor; 25. Welding slot; 26. Adjustment slot; 27. Hydraulic rod; 31. Connecting plate; 32. Mounting plate; 33. Sliding pair; 34. Rack; 35. Feed motor; 36. Gear; 37. Encircling plate; 41. First adjusting rod; 42. First fixing plate; 43. Second adjusting rod; 44. Second fixing plate; 45. Welding gun; 46. Supplementary light; 47. Electric actuator; 48. Third fixing plate; 51. Rotary table; 52. Angle adjustment motor; 100. Base; 10. Reference plate; 101. Heat insulation sheet; 102. Welding gap. Detailed Implementation

[0033] The embodiments illustrated in the accompanying drawings are for illustrative purposes only and should not be construed as limiting the scope of protection of this application. Other implementation methods obtained by those skilled in the art based on the described embodiments without inventive effort are all within the scope of protection of this application.

[0034] A longitudinal seam welding device, referring to Figure 1 , Figure 2 and Figure 6 The system includes a base 100, which serves as the supporting foundation for the entire equipment. It also includes a reference plate 10, which is longitudinally fixed to the base 100 and perpendicular to the mounting plane of the base 100. This reference plate 10 serves as a reference plane for welding operations. Two rows of parallel heat-insulating plates 101 are mounted on the surface of the reference plate 10. These two rows of heat-insulating plates 101 form a narrow welding gap 102 that allows the welding torch to pass through. Each heat-insulating plate 101 is fixed to the reference plate 10 by an individual screw. By tightening these screws, the position of the heat-insulating plate 101 can be finely adjusted, thereby achieving precise adjustment of the width of the welding gap 102. The heat-insulating plates 101 effectively block the transmission of high welding temperatures to the reference plate 10 body, reducing thermal deformation.

[0035] Figure 2 and Figure 3The welding device is located on one side of the reference plate 10. The welding device includes a mounting plate 32 parallel to and fixed to the reference plate 10. The mounting plate 32 is connected to the reference plate 10 via connecting plates 31 at both ends, causing the bottom of the mounting plate 32 to be suspended. On one surface of the mounting plate 32 facing outwards from the device, a sliding pair 33 is mounted. This sliding pair 33 includes a slide rail laid along the length of the mounting plate 32 and a matching slider. On the opposite surface of the mounting plate 32, a rack 34, also arranged along the length, is fixedly mounted.

[0036] Figure 3 and Figure 4 The welding device also includes a U-shaped annular plate 37, with its open side facing the reference plate 10. One end of the annular plate 37 is fixedly connected to the slider of the sliding pair 33, and the other end is equipped with a feed motor 35. A gear 36 is mounted on the output shaft of the feed motor 35, and the gear 36 meshes with a rack 34 on the mounting plate 32. When the feed motor 35 is working, the entire annular plate 37 can be driven to make a smooth linear feed motion along the slide rail through the transmission of the gear 36 and the rack 34.

[0037] Figure 3 and Figure 4 A welding mechanism is fixedly mounted on the circumferential plate 37. This welding mechanism includes an electric actuator 47 fixed to the circumferential plate 37, with a third fixing plate 48 fixed to the end of the output shaft of the electric actuator 47. A first adjusting rod 41 is mounted on the third fixing plate 48, which drives the first fixing plate 42 to move in one direction, such as the X-axis, via a threaded drive. A second adjusting rod 43 is mounted on the first fixing plate 42, which similarly drives the second fixing plate 44 to move in another direction, such as the Y-axis, via a threaded drive. The welding gun 45 is ultimately fixed to the second fixing plate 44. By extending and retracting the electric actuator 47 and adjusting the first and second adjusting rods 41 and 43, the position of the welding gun 45 can be adjusted in multiple mutually perpendicular directions within space, ensuring that the tip of the welding gun is precisely aligned with the weld seam. A supplementary light 46 is also provided near the welding gun 45 to provide backlighting during weld seam alignment.

[0038] Reference Figure 5 and Figure 6 The rotating device is located on the other side of the reference plate 10 opposite to the welding device. It includes a rotary table 51 for receiving and welding valve pipes, and an angle-adjusting motor 52 for driving the rotary table 51 to rotate precisely about its central axis.

[0039] Reference Figure 1 and Figure 7The lifting device, mounted on the base 100, is mainly used for aligning the workpiece vertically. It includes multiple vertically arranged hydraulic rods 27, the output ends of which are all fixedly connected to a horizontal lifting plate 21. Through the synchronous extension and retraction of the hydraulic rods 27, the lifting plate 21 can be driven to rise and fall stably in the vertical direction. A positioning column 22 is vertically fixed on the lifting plate 21, with its lower end suspended above the rotary table 51.

[0040] Reference Figure 8 The positioning post 22 has a sealed cavity structure inside, which can be filled with water or a special coolant. A valved inlet / outlet port is provided on the wall of the positioning post 22 for injecting and replacing the coolant. The positioning post 22 is made of metal to ensure structural strength. Two feature grooves are symmetrically machined on its cylindrical sidewall: one is a mounting groove 23, and the other is a welding groove 25. A light curtain area sensor 24 is embedded in the mounting groove 23. This sensor can emit and receive a fan-shaped planar light curtain. When an object partially blocks this light curtain, the sensor can accurately determine the outline of the object or the area it passes through by analyzing the number and position of the blocked beams. The welding groove 25 is an arc-shaped groove recessed towards the axis of the positioning post 22. Its function is to provide space for the weld bead (weld residue) on the back side of the weld during final welding, preventing the positioning post 22 body from pressing on the uncooled weld.

[0041] Reference Figure 7 An adjustment device, mounted on the lifting plate 21, is used to drive the positioning column 22 to make micro-movements in the horizontal plane. Specifically, an adjustment groove 26 is opened on the lifting plate 21, through which the positioning column 22 passes. The adjustment device includes a movable base 11 with a mounting hole 12. The positioning column 22 is rotatably mounted in this hole by bearings, and a limiting plate is provided at the top of the positioning column 22 to prevent axial movement. The adjustment device includes a translation mechanism and a rotation mechanism. The translation mechanism includes a track 13 fixed on the lifting plate 21, the direction of which is consistent with the length direction of the adjustment groove 26. The translation mechanism also includes a translation cylinder 14, which is slidably engaged with the track 13 through the movable base 11 and connected to the output shaft of the translation cylinder 14, so that it can be driven by the cylinder to move the positioning column 22 along the direction of the track 13, that is, towards or away from the reference plate 10. The rotating mechanism includes a rotary motor 15, which is connected to the top of the positioning column 22 via a set of gears 36, and can drive the positioning column 22 to rotate precisely around its own central axis.

[0042] The implementation principle of this application is as follows: During operation, the valve pipe workpiece, rolled into a cylindrical shape with longitudinal slits, is first placed on the rotary table 51. The equipment is initialized, and the hydraulic rod 27 of the lifting device raises the lifting plate 21 and the positioning column 22 to a high position. Then, the hydraulic rod 27 drives the positioning column 22 to descend, inserting it into the pipe from the top of the workpiece. Next, the translation cylinder 14 of the adjusting device actuates, pushing the positioning column 22. At this point, utilizing the complete cylindrical surface on its side wall (excluding the mounting groove 23 and welding groove 25), it moves towards the reference plate 10, initially pressing the workpiece against the heat insulation sheet 101 of the reference plate 10.

[0043] Subsequently, the translation cylinder 14 retracts slightly, creating a small gap between the positioning column 22 and the inner wall of the pipe. The rotary motor 15 starts, driving the positioning column 22 to rotate until the mounting groove 23 on its side wall and the light curtain area sensor 24 within the groove are aligned with the welding gap 102 on the reference plate 10. Simultaneously, the supplementary light 46 on the welding device is turned on, and light shines from one side of the reference plate 10 through the welding gap 102.

[0044] Angle adjustment motor 52 slowly drives rotary table 51, along with the workpiece on it, to rotate. Because the workpiece itself has an unclosed gap, when this gap rotates to a position aligned with the welding gap 102, the light emitted by supplementary lighting lamp 46 will pass through the gap to its maximum extent and be received by light curtain area sensor 24 on positioning column 22. The sensor detects the light-transmitting area in real time; when the detected light signal area reaches its maximum value, it is determined that the workpiece gap is precisely aligned with the welding gap 102, and rotary table 51 immediately stops. This process achieves automated visual alignment of the weld, replacing the traditional low-precision, low-efficiency manual visual alignment.

[0045] After alignment, the adjustment device operates again: the rotary motor 15 drives the positioning column 22 to rotate, aligning the welding groove 25 on its side wall with the aligned weld position; then the translation cylinder 14 pushes the positioning column 22 forward again, using the main body of the positioning column 22 to firmly press the workpiece against the reference plate 10, while the welding groove 25 reserves space for the back of the weld. Throughout the welding process, the cooling medium inside the positioning column 22 continuously absorbs and removes the welding heat conducted from the workpiece, keeping the temperature of the positioning column 22 body and the area in contact with the workpiece stable. This effectively prevents the preheating problem of subsequent workpieces caused by heat accumulation in traditional solid positioning columns 22, ensuring the consistency of the welding start conditions for workpieces in the same batch, thereby ensuring the uniformity and reliability of the weld quality.

[0046] Finally, driven by the feed motor 35, the welding gun 45 moves at a constant speed along the welding gap 102 to complete the automated welding of the entire longitudinal weld.

[0047] The above description is merely an embodiment of this application and is not intended to limit the scope of protection of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. A longitudinal seam welding device, characterized in that, include: Base (100); A reference plate (10) is longitudinally fixed on the base (100); at least two rows of heat insulation sheets (101) are provided on the reference plate (10), and a welding gap (102) is formed between the at least two rows of heat insulation sheets (101); A welding device is provided on one side of the reference plate (10) for performing welding operations along the length direction of the reference plate (10); A rotating device is disposed on the other side of the reference plate (10) relative to the welding device. The rotating device includes a rotating table (51) for receiving the workpiece to be welded; the rotating device also includes an angle adjusting motor (52) for driving the rotating table (51) to rotate precisely about its central axis. A lifting device is provided on the base (100). The lifting device includes a lifting plate (21) that can be raised and lowered, and a positioning column (22) fixed on the lifting plate (21). The positioning column (22) is used to extend into and press against the workpiece. The positioning column (22) has a sealed cavity inside, and the cavity is filled with a cooling medium; The side wall of the positioning column (22) is provided with an installation groove (23), and a light curtain area sensor (24) is provided in the installation groove (23); The light curtain area sensor (24) is configured to detect the light-transmitting area in real time. When the detected light signal area reaches the maximum value, it is determined that the workpiece gap has been precisely aligned with the welding gap (102), so that the rotating table (51) immediately stops rotating. The side wall of the positioning post (22) is also provided with a welding groove (25), which is recessed toward the axis of the positioning post (22); the mounting groove (23) and the welding groove (25) are symmetrically arranged; An adjustment device, disposed on the lifting plate (21), is used to drive the positioning column (22) to translate and rotate relative to the lifting plate (21); the adjustment device includes: A movable base (11) on which the positioning column (22) is rotatably mounted; A translation mechanism, connected to the movable seat (11), is used to drive the movable seat (11) and the positioning column (22) to translate in the horizontal direction; A rotating mechanism, connected to the positioning column (22), is used to drive the positioning column (22) to rotate around its own axis; The lifting plate (21) has an elongated adjustment groove (26), the positioning column (22) passes through the adjustment groove (26), and the translation mechanism drives the positioning column (22) to move along the length direction of the adjustment groove (26).

2. The longitudinal seam welding equipment according to claim 1, characterized in that, The welding apparatus includes: Mounting plate (32), the length direction of which is parallel to the reference plate (10); A sliding pair (33) is provided along the length direction of the mounting plate (32); The circumferential plate (37) is connected to the slider of the sliding pair (33); A feed drive mechanism is used to drive the circumferential plate (37) to move along the sliding pair (33); The welding gun (45) is mounted on the circumferential plate (37) via a multi-directional adjustment mechanism. A supplementary light (46) is also provided near the welding gun (45) to provide backlighting during the weld alignment process.

3. The longitudinal seam welding equipment according to claim 2, characterized in that, The feed drive mechanism includes a rack (34) fixed on the mounting plate (32), a motor mounted on the circumferential plate (37), and a gear (36) driven by the motor and meshing with the rack (34).

4. The longitudinal seam welding equipment according to claim 1, characterized in that, The heat insulation sheet (101) is independently fixed to the reference plate (10) by screws, and the width of the gap can be adjusted by adjusting the screws.

Images