A copper pipe butt welding device and a welding method

Abstract

The present application relates to copper pipe processing technical field, especially a kind of copper pipe butt welding device and welding method, annular slot is set up in the both ends of connecting sleeve ring, for respectively inserting the end of two copper pipes to be butt joint, welding layer is arranged on the inner wall of annular slot;Induction coil is arranged in the outer circle of connecting sleeve ring, and the local of connecting sleeve ring and copper pipe inserted in its both ends is heated. Two copper pipes are butt jointed by connecting sleeve ring, the butt welding operation of two copper pipes is realized, and the end of copper pipe, outer wall and inner wall can contact with the inner wall of annular slot, effectively increase the contact area of copper pipe and connecting sleeve ring, realize multi-region contact, improve welding strength;By the way of filling welding layer on the inner wall of annular slot, welding can be realized inside the butt joint position of copper pipe and connecting sleeve ring, avoid the problem of insufficient welding strength caused by traditional welding only limited to the local surface of copper pipe.

Description

Technical Field

[0001] This invention relates to the field of copper tube processing technology, and in particular to a copper tube butt welding device and welding method. Background Technology

[0002] Copper pipes, as an important type of metal pipe, are widely used in various industrial and civil fields such as refrigeration, HVAC, energy and chemical industry, shipbuilding, and urban water and gas supply due to their excellent thermal conductivity, corrosion resistance and machinability. In these applications, copper pipes usually need to be cut and connected according to complex installation requirements. Welding is one of the most critical processes to ensure that the piping system achieves permanent, high-strength and high-sealing connections.

[0003] Traditional welding methods involve flaring one end of a copper pipe and narrowing the other, or flaring or narrowing only one pipe while using the other pipe to its standard specifications. The two pipes are then interlocked using the difference in their end diameters. The connection is then heated, and a copper alloy welding rod is placed at the joint. The welding rod melts and welds the connection. However, this welding method only allows the molten welding rod to fill the surface of the joint, not penetrate into the gap. Although the interlocking method increases the contact area, the contact area is not fully utilized. The portion of the interlocking pipe hidden in the gap cannot contact the molten welding rod. Therefore, the welding position is only on a local surface of the pipe joint, resulting in low weld strength. Summary of the Invention

[0004] This invention provides a copper pipe butt welding device and welding method, which can effectively solve the problems in the background art.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0006] A copper pipe butt welding device, comprising:

[0007] A connecting collar is provided with annular slots at both ends for inserting the ends of two copper tubes to be connected, and a solder layer is provided on the inner wall of the annular slots.

[0008] An induction coil is disposed on the outer ring of the connecting collar to locally heat the connecting collar and the copper tubes inserted at both ends thereto.

[0009] Furthermore, the induction coil is mounted on the machine base, and a fixed clamp and a movable clamp are respectively mounted on both sides of the induction coil on the machine base. Both the fixed clamp and the movable clamp are coaxially mounted with the connecting collar.

[0010] The fixed clamp is fixed on the machine base by a first bracket. A guide rail is provided on the machine base corresponding to the movable clamp. The guide rail is parallel to the axis of the movable clamp. The movable clamp is slidably connected to the guide rail by a second bracket. The second bracket is driven by a compression cylinder to move along the length direction of the guide rail.

[0011] Furthermore, both ends of the connecting collar are set as slopes on the outer and inner walls of the annular slot section, and the inner and outer slopes converge toward the end face;

[0012] An inner ring groove and an outer ring groove are respectively provided on the inner wall and outer wall of the axial middle section of the connecting collar, and both the inner ring groove and the outer ring groove are recessed towards the center.

[0013] Furthermore, the induction coil includes a plurality of loops arranged side by side along its axial direction, and the loops include a plurality of angled lines arranged circumferentially thereon;

[0014] A post and a hole are respectively provided at both ends of the corner line, and two adjacent corner lines are connected through the post and the hole;

[0015] The two adjacent loops are connected by the posts and holes on the two corner lines at their beginning and end.

[0016] Furthermore, the insertion hole is formed by a plurality of arc-shaped pressure plates arranged along its circumference.

[0017] Furthermore, the induction coil is disposed inside the isolation cylinder, and notches are provided on both sides of the circumferential sidewall of the isolation cylinder, the notches extending radially along the isolation cylinder to its axis;

[0018] A U-shaped sealing plate is provided on the isolation cylinder corresponding to the notch. The U-shaped sealing plate cooperates with the isolation cylinder to form a through hole at its axis. The induction coil is coaxially arranged with the through hole.

[0019] Furthermore, the induction coil is mounted on the adjusting bracket and connected to the isolation cylinder via the adjusting bracket;

[0020] The adjusting bracket includes an arc-shaped synchronizing body, a push-pull plate, a guide plate, and a fixed base. Multiple fixed bases are arranged along the circumference of the induction coil. The fixed base is rotatably connected to the arc-shaped synchronizing body through the push-pull plate. The fixed base is rotatably connected to the inner wall of the isolation cylinder through the guide plate. The arc-shaped synchronizing body is driven to move along the axial direction of the isolation cylinder by a first power device.

[0021] Multiple angles located on the same side of the axis of the induction coil are mounted on the same fixed base. The push-pull plate and the guide plate are both inclined in opposite directions along the radial direction of the isolation cylinder. The rotation axes at both ends of the push-pull plate and the guide plate are perpendicular to the axis of the induction coil.

[0022] Furthermore, a limiting plate is provided on the inner wall of the periphery of the isolation cylinder along its axial direction, and the arc-shaped synchronizing body is slidably connected to the limiting plate;

[0023] A slide bar is provided on the arc-shaped synchronizing body along the axial direction of the isolation cylinder. The slide bar extends to the outside of the isolation cylinder and is connected to the first power device.

[0024] The first power device includes a push-pull cylinder and a connecting rod, wherein the push-pull cylinder drives the slide rod to move along its length direction via the connecting rod.

[0025] Furthermore, a slide rail is provided on the isolation cylinder along its circumference, and the U-shaped sealing plate is slidably connected to the slide rail;

[0026] A positioning frame is provided on the U-shaped sealing plate. The positioning frame is provided with a guide groove and a positioning tooth. The guide groove is arranged radially along the isolation cylinder. The positioning frame is slidably connected to the guide block on the isolation cylinder through the guide groove. An arc-shaped rack is provided on the slide rail corresponding to the positioning tooth.

[0027] A method for butt welding of copper pipes, using the aforementioned copper pipe butt welding device, includes the following steps:

[0028] Insert the two copper tubes into the two ends of the through hole on the isolation cylinder, and mate them with the annular slots at both ends of the connecting collar in the induction coil;

[0029] The first power device drives the arc-shaped synchronizing body of the adjusting bracket to move axially along the isolation cylinder, adjusting the inner diameter of the induction coil to match the connecting collar.

[0030] By energizing the induction coil and heating it through induction, the connecting collar and the ends of the two copper tubes connected to it are heated.

[0031] The flux layer inside the annular slot on the connecting collar is heated and promotes a softened connection between the connecting collar and the end of the copper tube.

[0032] The hydraulic cylinder drives the movable jacket to squeeze the two copper tubes to the connecting collar, causing the connecting collar to undergo plastic deformation, and the ends of the copper tubes fill the gaps in the annular slot.

[0033] The induction coil is de-energized, and the two copper tubes and connecting collar are allowed to cool and the welding is completed.

[0034] The first power device drives the arc-shaped synchronous body to move, causing multiple fixed seats to move away from each other radially along the isolation cylinder, and splitting the induction coil;

[0035] Slide the U-shaped sealing plate away from the gap in the isolation cylinder and remove the welded copper pipe from the gap.

[0036] The beneficial effects of this invention are as follows:

[0037] This invention employs annular slots at both ends of the connecting collar, allowing the ends of two copper tubes to be inserted into the two annular slots respectively. This enables the two copper tubes to be connected to each other via the connecting collar, and the ends, outer walls, and inner walls of the copper tubes can all contact the inner wall of the annular slots, effectively increasing the contact area between the copper tubes and the connecting collar, achieving multi-area contact, and improving welding strength. By filling the inner wall of the annular slots with a layer of flux, welding can be achieved at the contact surface of the copper tube and the connecting collar, avoiding the problem of insufficient welding strength caused by traditional welding being limited to a local surface of the copper tube. Attached Figure Description

[0038] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0039] Figure 1 This is a schematic diagram of the copper tube butt welding device in this invention;

[0040] Figure 2 This is a partial cross-sectional schematic diagram of the connecting collar in this invention;

[0041] Figure 3 This is a schematic diagram of the isolation cylinder and its induction coil in this invention;

[0042] Figure 4 This is a schematic diagram of the structure of the isolation cylinder in this invention;

[0043] Figure 5 This is a schematic diagram of the positioning frame in this invention;

[0044] Figure 6 This is a schematic diagram of the structure of the adjusting bracket in this invention;

[0045] Figure 7 This is a schematic diagram of the adjustment bracket from another perspective in this invention;

[0046] Figure 8 This is a schematic diagram of the structure of the induction coil in this invention;

[0047] Figure 9 This is a schematic diagram of the linear loop structure in this invention.

[0048] Reference numerals: 1. Connecting collar; 11. Annular slot; 12. Welding flux layer; 13. Slope; 14. Inner annular groove; 15. Outer annular groove; 2. Induction coil; 21. Wire loop; 22. Angle wire; 23. Insert post; 24. Insertion hole; 241. Arc-shaped pressure plate; 31. Fixed sleeve; 32. Movable sleeve; 33. First support; 34. Second support; 35. Extrusion cylinder; 4. Isolation cylinder; 41. Notch; 42. U-shaped sealing plate; 43. 44. Through hole; 44. Slide rail; 441. Arc rack; 45. Positioning frame; 451. Guide groove; 452. Positioning tooth; 46. Guide block; 5. Adjusting bracket; 51. Arc synchronizer; 511. Slide rod; 52. Push-pull plate; 53. Guide plate; 54. Fixed seat; 55. Limiting plate; 6. First power unit; 61. Push-pull cylinder; 62. Connecting rod; 7. Second power unit; 8. Machine base; 81. Guide rail; 9. Copper pipe. Detailed Implementation

[0049] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0050] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly attached to the other element or there may be an intervening element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0051] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0052] This invention discloses a copper tube butt welding device, such as... Figures 1 to 6 As shown, it includes: a connecting collar 1, with annular slots 11 at both ends of the connecting collar 1 for inserting the ends of two copper tubes 9 to be connected, and a flux layer 12 is provided on the inner wall of the annular slots 11; and an induction coil 2, which is located on the outer ring of the connecting collar 1 to locally heat the connecting collar 1 and the copper tubes 9 inserted at both ends.

[0053] In this invention, the connecting collar 1 is located between the two copper tubes 9 to be welded. The two copper tubes 9 and the connecting collar 1 are coaxially arranged. Both ends of the connecting collar 1 are provided with annular slots 11 that are coaxial with it. The end areas of the copper tubes 9 are inserted into the annular slots 11, so that the connecting collar 1 and each copper tube 9 have a large overlap and contact area, achieving a large-area connection during welding. The flux layer 12 covers three surfaces of the inner wall of the annular slot 11, so that the end, outer wall and inner wall of the copper tube 9 are in contact with the flux layer 12, achieving welding of the end, inner wall and outer wall of the copper tube 9 during welding. In contrast, the traditional welding method can only achieve partial connection of the outer wall or inner wall of the copper tube 9. The solution of this invention can increase the welding contact area.

[0054] In the specific implementation process, such as Figure 2 As shown, the ends of the two copper tubes 9 are respectively inserted into the annular slots 11 at both ends of the connecting collar 1. The connecting collar 1 and the inserted ends of the copper tubes 9 are placed into the induction coil 2. The induction coil 2 is energized and heated by electromagnetic induction to heat the connecting collar 1, the flux layer 12 and the end areas of the copper tubes 9. The flux layer 12 promotes the softening and connection of the connecting collar 1 and the ends of the two copper tubes 9, so that both copper tubes 9 are welded to the connecting collar 1, thus achieving the purpose of butt welding of the two copper tubes 9.

[0055] By using annular slots 11 at both ends of the connecting collar 1, the ends of the two copper tubes 9 can be inserted into the two annular slots 11 respectively, thereby connecting the two copper tubes 9 to each other through the connecting collar 1. The ends, outer walls, and inner walls of the copper tubes 9 can all contact the inner wall of the annular slots 11, effectively increasing the contact area between the copper tubes 9 and the connecting collar 1 and improving the welding strength. By filling the inner wall of the annular slots 11 with a flux layer 12, welding can be achieved at the mating contact surface between the copper tubes 9 and the connecting collar 1, avoiding the problem of insufficient welding strength caused by traditional welding being limited to a local surface of the copper tubes 9.

[0056] In this embodiment, as Figure 1 As shown, the induction coil 2 is mounted on the machine base 8. A fixed sleeve 31 and a movable sleeve 32 are respectively mounted on both sides of the induction coil 2 on the machine base 8. Both the fixed sleeve 31 and the movable sleeve 32 are coaxially mounted with the connecting collar 1. The fixed sleeve 31 is fixed to the machine base 8 by the first bracket 33. A guide rail 81 is mounted on the machine base 8 corresponding to the movable sleeve 32. The guide rail 81 is parallel to the axis of the movable sleeve 32. The movable sleeve 32 is slidably connected to the guide rail 81 by the second bracket 34. The second bracket 34 is driven by the extrusion cylinder 35 to move along the length direction of the guide rail 81.

[0057] To ensure smooth insertion of the end of the copper tube 9 into the annular slot 11 at the end of the connecting collar 1, the diameter of the annular slot 11 is set larger than the diameter and wall thickness of the copper tube 9. Considering that a gap will exist between the copper tube 9 and the annular slot 11 after they are joined, and that this gap will exist on both the outer and inner walls of the copper tube 9, this embodiment adopts a compression connection method between the copper tube 9 and the connecting collar 1 to avoid gaps after welding. When the induction coil 2 heats the connecting collar 1 and the end of the copper tube 9 on it, the compression cylinder 35 can push the second bracket 34 to make the fixed copper tube 9 on the movable clamp 32 move along its axial direction. The connecting collar 1 is moved and squeezed, while the connecting collar 1 squeezes the copper tube 9 on the fixed sleeve 31, thus forming the effect of the two copper tubes 9 squeezing the connecting collar 1; part of the copper tube 9 in the annular slot 11 softens due to heat, and the squeezing of the copper tube 9 on the connecting collar 1 will fill the annular slot 11 with the softened part of the copper tube 9, and the squeezing of the end of the copper tube 9 on the inner wall of the annular slot 11 will cause the part of the connecting collar 1 on the inner and outer sides of the copper tube 9 to adhere to the inner and outer walls of the copper tube 9, thereby filling the gap and realizing the tight welding of the connecting collar 1 and the copper tube 9.

[0058] Furthermore, during the compression process of the copper tube 9 onto the connecting collar 1, the connecting collar 1 also softens, thus increasing the thickness of the middle part of the connecting collar 1; see [link to previous text]. Figure 2 As shown, the outer and inner walls of the connecting collar 1 located at both ends of the annular slot 11 are both set as slopes 13, and the inner and outer slopes 13 converge toward the end face; an inner annular groove 14 and an outer annular groove 15 are respectively opened on the inner and outer walls of the middle section of the connecting collar 1 in the axial direction, and both the inner annular groove 14 and the outer annular groove 15 are recessed toward the center.

[0059] When the two copper tubes 9 squeeze the connecting collar 1, the material in the middle of the connecting collar 1 increases, and the inner ring groove 14 and outer ring groove 15 on the connecting collar 1 gradually disappear, so as to avoid the wall thickness in the middle area of ​​the connecting collar 1 being too large after the two copper tubes 9 have finished squeezing the connecting collar 1. The slope 13 can make the local connecting collar 1 on the inner and outer sides of the copper tubes 9 more easily deformed, thereby improving the tightness of the fit between the connecting collar 1 and the copper tubes 9.

[0060] As a preferred embodiment of the present invention, such as Figure 8 As shown, the induction coil 2 includes multiple coil loops 21 arranged side by side along its axial direction, and each coil loop 21 includes multiple corner lines 22 arranged circumferentially. A post 23 and a socket 24 are respectively provided at both ends of the corner line 22, and adjacent corner lines 22 are connected by the post 23 and the socket 24. Adjacent coil loops 21 are connected by the post 23 and the socket 24 on the two corner lines 22 at their beginning and end.

[0061] The wire loop 21 has a polygonal structure. Its "straight edge" is formed by the connection between the plug 23 and the socket 24. The gap between the "straight edge" of the wire loop 21 and the copper tube 9 is the smallest, the magnetic field is the strongest, and the generated eddy currents and heat are also the greatest. At the corner of the polygon, the gap is the largest, the magnetic field is the weakest, and the heating effect is also weak. This arrangement can create an alternating "strong-weak-strong" heating mode on the circumference of the copper tube 9. This heating mode can improve the penetration of local temperature of the copper tube 9, so that the heat of the strong heating area has enough time to conduct to the inside and sides of the copper tube 9 before entering the next strong heating area. This intermittent strong heating helps the heat to conduct inward more fully, which may reduce the radial temperature difference between the inner and outer walls of the copper tube 9 and avoid surface overheating. Because the magnetic field is more concentrated in the straight edge section, it is more tightly coupled with the copper tube 9 and has less magnetic leakage, allowing more energy to be effectively transferred to the copper tube 9 instead of being wasted in the surrounding air. The induction coil 2 is rotatably set by the second power device 7. After the multiple strong heating zones on the induction coil 2 have completed heat penetration into multiple local areas of the copper tube 9, the induction coil 2 can be rotated to allow the area that has reached the required temperature to spread along the circumference of the copper tube 9, thereby achieving comprehensive heating of the copper tube 9. In actual use, by adopting the above heating mode, the welding position of the copper tube 9 and the connecting collar 1 can be gradually spread along the circumference of the copper tube 9, rather than heating and welding all positions in the circumference of the copper tube 9 at the same time. This makes it easier to make the deformation and stress transmission of the copper tube 9 and the connecting collar 1 more uniform, thus improving the welding quality.

[0062] See Figure 9 As shown, by changing the depth of the insertion post 23 into the insertion hole 24, the length of the "straight edge" is adjusted, the distance between two adjacent angle lines 22 is changed, and thus the inner diameter of the wire loop 21 is changed. This makes it easier for the induction coil 2 to be compatible with copper tubes 9 and connecting collars 1 of different diameters. At the same time, after the copper tube 9 is welded, the insertion post 23 can be pulled out from the insertion hole 24, that is, the angle lines 22 are separated from each other. This allows the copper tube 9 to be moved out of the induction coil 2 radially, rather than being pulled out of the induction coil 2 along the axis of the induction coil 2, which facilitates the disassembly of the copper tube 9, especially when the copper tube 9 is long.

[0063] Furthermore, if the gap between the plug 23 and the socket 24 is small, it will be difficult to insert due to friction. If the gap between the plug 23 and the socket 24 is large, there will be gaps when inserting, which may result in a small electrical connection area between the plug 23 and the socket 24 or even a complete power outage.

[0064] To solve the above problems, such as Figure 9As shown, the insertion hole 24 is surrounded by multiple arc-shaped pressure plates 241 arranged along its circumference. An adjustment gap is formed between two adjacent arc-shaped pressure plates 241. The arc-shaped pressure plates 241 are inclined towards the inside of the insertion hole 24 along the length direction of the insertion hole 24. When the insertion post 23 is inserted into the insertion hole 24, the end of the insertion post 23 will squeeze and separate the arc-shaped pressure plates 241 outward, so that the insertion post 23 can be smoothly inserted between the arc-shaped pressure plates 241. At this time, the adjustment gap will increase, and the arc-shaped pressure plates 241 can always maintain a good contact state with the insertion post 23. This can improve the tightness of the connection between the insertion post 23 and the insertion hole 24, and also realize the smooth insertion and adjustment work.

[0065] In this embodiment, as Figures 1 to 4 As shown, the induction coil 2 is installed inside the isolation cylinder 4. A notch 41 is provided on both sides of the circumferential side wall of the isolation cylinder 4, and the notch 41 extends radially along the isolation cylinder 4 to its axis. A U-shaped sealing plate 42 is provided on the isolation cylinder 4 corresponding to the notch 41. The U-shaped sealing plate 42 cooperates with the isolation cylinder 4 to form a through hole 43 at its axis. The induction coil 2 is coaxially arranged with the through hole 43.

[0066] During the initial welding, the U-shaped sealing plate 42 is sealed on the notch 41. Both ends of the isolation cylinder 4 have through holes 43, and the through holes 43 are composed of the end of the U-shaped sealing plate 42 and the part of the notch 41. After the copper tube 9 is welded, the U-shaped sealing plate 42 is opened, the induction coil 2 is disassembled, and the copper tube 9 can be directly removed from the isolation cylinder 4 through the notch 41. The isolation cylinder 4 and the U-shaped sealing plate 42 can enclose the welding work of the copper tube 9 in a space, thereby improving the welding safety and avoiding the injury to workers caused by sparks, high temperature, and bright light.

[0067] As a preferred embodiment of the above, to facilitate the operation and use of the U-shaped sealing plate 42, such as Figures 3 to 5 As shown, a slide rail 44 is provided on the isolation cylinder 4 along its circumference, and the U-shaped sealing plate 42 is slidably connected to the slide rail 44; a positioning frame 45 is provided on the U-shaped sealing plate 42, and a guide groove 451 and a positioning tooth 452 are provided on the positioning frame 45. The guide groove 451 is arranged radially along the isolation cylinder 4, and the positioning frame 45 is slidably connected to the guide block 46 on the isolation cylinder 4 through the guide groove 451. An arc-shaped rack 441 is provided on the slide rail 44 corresponding to the positioning tooth 452.

[0068] When the U-shaped sealing plate 42 is opened or closed, it is only necessary to rotate the U-shaped sealing plate 42 on the isolation cylinder 4. The guide block 46 and the guide groove 451 guide the movement direction of the positioning frame 45 on the U-shaped sealing plate 42, so that the positioning frame 45 can only move in the radial direction of the isolation cylinder 4 where the U-shaped sealing plate 42 is located. The positioning frame 45 is provided with positioning teeth 452, and an arc-shaped rack 441 is provided in a local area of ​​the arc-shaped outer wall of the slide rail 44. The positioning teeth 452 and the arc-shaped rack 441 work together to position and fix the U-shaped sealing plate 42 without affecting the guiding effect of the slide rail 44 on the U-shaped sealing plate 42. When it is necessary to move the U-shaped sealing plate 42, the worker can pull the positioning frame 45 to disengage the positioning teeth 452 from the arc-shaped rack 441, thereby unlocking the U-shaped sealing plate 42. When it is necessary to lock the position of the U-shaped sealing plate 42, the worker only needs to press the positioning frame 45 to insert the positioning teeth 452 into the corresponding arc-shaped rack 441. To prevent the U-shaped sealing plate 42 from moving freely, an elastic body can be provided between the positioning frame 45 and the U-shaped sealing plate 42 so that the positioning teeth 452 and the arc-shaped rack 441 remain engaged and positioned in the natural state.

[0069] In this embodiment, as Figure 7 As shown, the induction coil 2 is mounted on the adjusting bracket 5 and connected to the isolation cylinder 4 via the adjusting bracket 5. The adjusting bracket 5 includes an arc-shaped synchronizing body 51, a push-pull plate 52, a guide plate 53, and a fixed base 54. Multiple fixed bases 54 are arranged around the induction coil 2. The fixed base 54 is rotatably connected to the arc-shaped synchronizing body 51 via the push-pull plate 52. The fixed base 54 is rotatably connected to the inner wall of the isolation cylinder 4 via the guide plate 53. The arc-shaped synchronizing body 51 is driven to move axially along the isolation cylinder 4 by the first power device 6. Multiple angles 22 located on the same side of the axis of the induction coil 2 are mounted on the same fixed base 54. The push-pull plate 52 and the guide plate 53 are both inclined in opposite directions along the radial direction of the isolation cylinder 4. The rotation axes at both ends of the push-pull plate 52 and the guide plate 53 are perpendicular to the axis of the induction coil 2.

[0070] In the circumferential direction of the induction coil 2, several angle lines 22 are divided into multiple groups, each group is supported by a fixed seat 54. The fixed seat 54 can be made of high-temperature resistant plastic injection molding. The guide plate 53 on the fixed seat 54 can guide and support the fixed seat 54. When the push-pull plate 52 is driven by the arc-shaped synchronizing body 51 to pull the fixed seat 54 to move, it will cause the guide plate 53 to tilt and rotate. The axial position of the fixed seat 54 remains unchanged, but it moves radially along the isolation cylinder 4, which synchronously drives several angle lines 22 on the wire ring 21 to move smoothly, thereby changing the inner diameter of the induction coil 2, or splitting the several angle lines 22 connected circumferentially upward of the induction coil 2.

[0071] Furthermore, a limiting plate 55 is provided on the inner wall of the periphery of the isolation cylinder 4 along its axial direction, and the arc-shaped synchronizing body 51 is slidably connected to the limiting plate 55; a sliding rod 511 is provided on the arc-shaped synchronizing body 51 along the axial direction of the isolation cylinder 4, the sliding rod 511 extends to the outside of the isolation cylinder 4 and is connected to the first power device 6; the first power device 6 includes a push-pull cylinder 61 and a connecting rod 62, and the push-pull cylinder 61 drives the sliding rod 511 to move along its length direction through the connecting rod 62.

[0072] Specifically, multiple slide rods 511 are arranged circumferentially on the arc-shaped synchronizing body 51. The first power device 6 is arranged circumferentially on the isolation cylinder 4 corresponding to the slide rods 511. Multiple push-pull cylinders 61 can drive the arc-shaped synchronizing body 51 to move through multiple connecting rods 62 and multiple slide rods 511. The arc-shaped synchronizing body 51 moves along the axis of the isolation cylinder 4. At this time, the arc-shaped synchronizing body 51 can synchronously drive several push-pull plates 52 to move, so that several fixed seats 54 move synchronously, ensuring that several angle lines 22 on the wire ring 21 move synchronously relative to each other. This avoids the situation where several fixed seats 54 cannot move synchronously, and the movement trajectory of the fixed seats 54 is tilted, causing several angle lines 22 on the wire ring 21 to be misaligned and twisted.

[0073] This invention further discloses a method for butt welding of copper tubes 9, comprising the following steps:

[0074] Two copper tubes 9 are inserted into the two ends of the through hole 43 on the isolation cylinder 4 respectively, and are connected to the annular slots 11 at both ends of the connecting collar 1 in the induction coil 2.

[0075] The first power device 6 drives the arc-shaped synchronous body 51 of the adjusting bracket 5 to move axially along the isolation cylinder 4, adjusting the inner diameter of the induction coil 2 to match the connecting collar 1.

[0076] Power is supplied to the induction coil 2, and the ends of the connecting collar 1 and the two copper tubes 9 connected to it are heated by induction heating.

[0077] The flux layer 12 inside the annular slot 11 on the connecting collar 1 is heated and promotes the softening connection between the connecting collar 1 and the end of the copper tube 9.

[0078] The hydraulic cylinder 35 drives the movable sleeve 32 to squeeze the two copper tubes 9 to squeeze the connecting collar 1, causing the connecting collar 1 to undergo plastic deformation, and the ends of the copper tubes 9 fill the gap in the annular slot 11.

[0079] The induction coil 2 is de-energized, and the two copper tubes 9 and the connecting collar 1 are allowed to cool and the welding is completed.

[0080] The first power device 6 drives the arc-shaped synchronous body 51 to move, which in turn drives multiple fixed seats 54 to move away from each other radially along the isolation cylinder 4 and splits the induction coil 2.

[0081] Slide the U-shaped sealing plate 42 away from the notch 41 of the isolation cylinder 4, and remove the welded copper pipe 9 from the notch 41.

[0082] This welding method enables large-area welding connections between two copper tubes 9, and the welding position can be located on the outer wall, end, or inner wall of the copper tube 9 within the annular slot 11, thereby improving the welding strength and avoiding the problem of insufficient welding strength caused by the welding position only existing on the surface of the copper tube 9.

[0083] Those skilled in the art should understand that this invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to this invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A copper pipe butt welding device, characterized in that, include: A connecting collar is provided with annular slots at both ends for inserting the ends of two copper tubes to be connected, and a solder layer is provided on the inner wall of the annular slots. An induction coil is disposed on the outer ring of the connecting collar to locally heat the connecting collar and the copper tubes inserted at both ends thereto; The induction coil is mounted on the machine base, and a fixed clamp and a movable clamp are respectively provided on both sides of the induction coil on the machine base. Both the fixed clamp and the movable clamp are coaxially arranged with the connecting collar. The fixed sleeve is fixed on the machine base by the first bracket. A guide rail is provided on the machine base corresponding to the movable sleeve. The guide rail is parallel to the axis of the movable sleeve. The movable sleeve is slidably connected to the guide rail by the second bracket. The second bracket is driven by the extrusion cylinder to move along the length direction of the guide rail. Both ends of the connecting collar are set as slopes on the outer and inner walls of the annular slot section, and the inner and outer slopes converge toward the end face; An inner ring groove and an outer ring groove are respectively provided on the inner wall and the outer wall of the axial middle section of the connecting collar, and both the inner ring groove and the outer ring groove are recessed towards the center; The induction coil includes a plurality of wire loops arranged side by side along its axial direction, and the wire loops include a plurality of diagonal lines arranged circumferentially thereon. A post and a hole are respectively provided at both ends of the corner line, and two adjacent corner lines are connected through the post and the hole; Two adjacent loops are connected by the posts and holes on the two corner lines at their beginning and end; The insertion hole is formed by a plurality of arc-shaped pressure plates arranged along its circumference; The induction coil is disposed inside the isolation cylinder, and notches are provided on both sides of the circumferential sidewall of the isolation cylinder, the notches extending radially along the isolation cylinder to its axis; A U-shaped sealing plate is provided on the isolation cylinder corresponding to the notch. The U-shaped sealing plate cooperates with the isolation cylinder to form a through hole at its axis. The induction coil is coaxially arranged with the through hole. The induction coil is mounted on the adjusting bracket and connected to the isolation cylinder through the adjusting bracket; The adjusting bracket includes an arc-shaped synchronizing body, a push-pull plate, a guide plate, and a fixed base. Multiple fixed bases are arranged along the circumference of the induction coil. The fixed base is rotatably connected to the arc-shaped synchronizing body through the push-pull plate. The fixed base is rotatably connected to the inner wall of the isolation cylinder through the guide plate. The arc-shaped synchronizing body is driven to move along the axial direction of the isolation cylinder by a first power device. Multiple angles located on the same side of the axis of the induction coil are mounted on the same fixed base. The push-pull plate and the guide plate are both inclined in opposite directions along the radial direction of the isolation cylinder. The rotation axes at both ends of the push-pull plate and the guide plate are perpendicular to the axis of the induction coil. A slide rail is provided on the isolation cylinder along its circumference, and the U-shaped sealing plate is slidably connected to the slide rail; A positioning frame is provided on the U-shaped sealing plate. The positioning frame is provided with a guide groove and a positioning tooth. The guide groove is arranged radially along the isolation cylinder. The positioning frame is slidably connected to the guide block on the isolation cylinder through the guide groove. An arc-shaped rack is provided on the slide rail corresponding to the positioning tooth.

2. The copper pipe butt welding device according to claim 1, characterized in that, A limiting plate is provided on the circumferential inner wall of the isolation cylinder along its axial direction, and the arc-shaped synchronizing body is slidably connected to the limiting plate; A slide bar is provided on the arc-shaped synchronizing body along the axial direction of the isolation cylinder. The slide bar extends to the outside of the isolation cylinder and is connected to the first power device. The first power device includes a push-pull cylinder and a connecting rod, wherein the push-pull cylinder drives the slide rod to move along its length direction via the connecting rod.

3. A method for butt welding of copper pipes, characterized in that, The copper pipe butt welding device according to claim 2 includes the following steps: Insert the two copper tubes into the two ends of the through hole on the isolation cylinder, and mate them with the annular slots at both ends of the connecting collar in the induction coil; The first power device drives the arc-shaped synchronizing body of the adjusting bracket to move axially along the isolation cylinder, adjusting the inner diameter of the induction coil to match the connecting collar. By energizing the induction coil and heating it through induction, the connecting collar and the ends of the two copper tubes connected to it are heated. The flux layer inside the annular slot on the connecting collar is heated and promotes a softened connection between the connecting collar and the end of the copper tube. The hydraulic cylinder drives the movable jacket to squeeze the two copper tubes to the connecting collar, causing the connecting collar to undergo plastic deformation, and the ends of the copper tubes fill the gaps in the annular slot. The induction coil is de-energized, and the two copper tubes and connecting collar are allowed to cool and the welding is completed. The first power device drives the arc-shaped synchronous body to move, causing multiple fixed seats to move away from each other radially along the isolation cylinder, and splitting the induction coil; Slide the U-shaped sealing plate away from the gap in the isolation cylinder and remove the welded copper pipe from the gap.

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