A steel pipe straightening apparatus and a straightening process

Abstract

The present application belongs to the technical field of steel pipe straightening, and discloses a steel pipe straightening device and a straightening process. The steel pipe straightening device comprises a mandrel, a guide assembly, a repair head, an inner circle finishing head, a winding assembly and a heating module. The guide assembly comprises a plurality of sleeve pipes which are sequentially inserted in the axial direction. The last sleeve pipe is fixedly connected with the mandrel. The winding assembly is connected with the guide assembly to drive the sleeve pipes of the guide assembly to form a rigid or flexible straight cylinder structure. The heating module is arranged on the outer surface of the sleeve pipe and located in front of the repair head, and is used for heating the inner wall of the steel pipe. The repair head is installed on the sleeve pipe and is adapted to move into the steel pipe along with the sleeve pipe. In the present application, the steel pipe straightening process can repair the concave structure of the steel pipe by heating and repairing the inside of the steel pipe during the treatment process, thereby reducing the complexity of the operation, reducing the waste of energy consumption and lowering the manufacturing cost.

Description

Technical Field

[0001] This invention relates to the field of steel pipe straightening, and more specifically, to a steel pipe straightening device and a straightening process. Background Technology

[0002] Steel pipes, as a key engineering structural material, play an irreplaceable supporting role in industries such as petrochemicals, machinery manufacturing, and construction. However, due to multiple factors, including fluctuations in rolling process parameters, the need for standardized transportation and handling operations, and the complexity of on-site construction environments, steel pipes are highly susceptible to geometric distortions throughout their entire life cycle. A particularly prominent issue is the formation of localized depressions (appearing as concave from the outside but convex from the inside). These localized depressions not only significantly weaken the pipe's axial load-bearing capacity and resistance to external pressure but may also lead to stress concentration and corrosion cracking risks in media transport pipelines.

[0003] In the process of straightening steel pipes, for complex deformed components with bending parts and outer wall depressions, traditional straightening equipment lacks the ability to control multi-physics field coupling, and therefore cannot achieve integrated operation of deformation correction and depression defect repair. It is necessary to use special shaping equipment to perform hot pressing correction on the depression area, and then transfer it to the straightening unit for secondary heating and straightening after it cools to room temperature. This separate processing method increases the complexity of the operation, and requires repeated heating of the steel pipe with long intervals, resulting in energy waste and increased manufacturing costs. Summary of the Invention

[0004] This application aims to address at least one of the technical problems existing in the prior art. To this end, this application proposes a steel pipe straightening device and straightening process, which repairs the dented structure of the steel pipe by heating the inside of the steel pipe and repairing the dents before straightening, thereby reducing the complexity of operation, reducing energy waste, and lowering manufacturing costs.

[0005] To solve the above-mentioned technical problems, this application provides a steel pipe straightening device, including a mandrel, a guide assembly, a repair head, an inner circle finishing head, a winding assembly, and a heating module;

[0006] The guide assembly includes multiple sleeves that are inserted sequentially along the axis, with the last sleeve being fixedly connected to the mandrel.

[0007] The winding assembly is connected to the guiding assembly so that the multiple sleeves of the guiding assembly are connected to form a rigid or flexible cylindrical structure.

[0008] The heating module is disposed on the outer surface of the sleeve and located in front of the repair head, and is used to heat the inner wall of the steel pipe;

[0009] The repair head is mounted on the sleeve and is adapted to move into the steel pipe along with the sleeve.

[0010] The inner circle finishing head is mounted on the mandrel and is adapted to move with the mandrel into the steel pipe to finish the inner wall of the steel pipe.

[0011] Preferably, one end of the sleeve is a first end, and the other end of the sleeve is a second end. The sleeve includes a positioning groove disposed at the first end and a positioning end formed at the second end. A movable cavity and a frustum-shaped slot adapted to the shape of the positioning end are sequentially disposed along the axial direction inside the sleeve. The slot is connected to the movable cavity, and the movable cavity is connected to the positioning groove. The positioning groove is a conical groove, and at least two mounting grooves are opened on the conical surface of the positioning groove in the circumferential direction. Each mounting groove is provided with an elastic abutment.

[0012] The outer wall of the second end of the sleeve is provided with an annular flange, and the annular flange forms a clearance fit with the movable cavity.

[0013] Preferably, two sliders are symmetrically arranged on the outer surface of the sleeve, and the corresponding sliders on the outside of the sleeve are arranged axially.

[0014] The winding assembly includes a mounting base fixed to the sleeve at the front end, two ropes, a drive assembly that controls the synchronous winding and unwinding of the ropes, and at least two elastic telescopic mechanisms.

[0015] The rear ends of the two ropes are respectively fixedly connected to a fixing block, which is mounted on the mandrel. The front ends of the two ropes pass through the corresponding sliders and are connected to the drive assembly. The sliders limit the position of the sleeve.

[0016] The elastic telescopic mechanism is adapted to slide along the inner wall of the steel pipe and provide radial support for the guide assembly.

[0017] Preferably, the elastic abutment is a metal spring sheet, the fixed end of which is embedded in the mounting groove, and the free end of which extends toward the sleeve axis to provide elastic force for the axial relative movement of adjacent sleeves.

[0018] Preferably, the driving component includes:

[0019] An asynchronous motor fixed to the end of the mounting base;

[0020] Two shaft supports fixed to the mounting base;

[0021] A rotatable reel is connected between the two shaft supports, and a spacer is fixedly provided in the middle of the reel to separate the two ropes;

[0022] Gears are respectively fixed to the output end of the asynchronous motor and the end of the reel, and the two gears mesh with each other;

[0023] The front ends of the two ropes are respectively wrapped around the outer wall of the reel on both sides of the spacer, and after passing through the rope hole of the mounting base, they pass through the corresponding slider and extend to the fixing block.

[0024] Preferably, the elastic telescopic mechanism includes:

[0025] A hinged base fixed to the outer wall of the sleeve;

[0026] The elastic reset units are symmetrically arranged at both ends of the hinge base. Each elastic reset unit includes a first rotating shaft rotatably connected to the hinge base, a torsion spring sleeved on the first rotating shaft, a support arm fixed on the first rotating shaft, and a guide wheel rotatably connected to the support arm.

[0027] One end of the torsion spring is connected to the first rotating shaft, and the other end of the torsion spring is connected to the hinge base;

[0028] The guide wheel is rotatably connected to the end of the support arm via a second rotating shaft, and the guide wheel rolls along the axis of the steel pipe.

[0029] Preferably, the heating module includes:

[0030] A ring-shaped heating element, wherein the surface of the heating element maintains a heat conduction distance from the inner wall of the steel pipe;

[0031] A heat insulation sleeve is connected to the end of the heating element, and the heat insulation sleeve is fixedly connected to the sleeve tube;

[0032] At least two elastic positioning units are circumferentially distributed on the heat insulation sleeve, each elastic positioning unit comprising:

[0033] A limiting rod that penetrates the heat insulation sleeve and slides therewith;

[0034] A wheel bracket fixed to the end of the limiting rod, wherein a positioning wheel is rotatably connected inside the wheel bracket;

[0035] A second spring is sleeved on the limiting rod, and the two ends of the second spring abut against the heat insulation sleeve and the wheel bracket, respectively;

[0036] A limiting ring is provided at the end of the limiting rod, and the limiting ring is used to limit the maximum extension displacement of the limiting rod.

[0037] Preferably, the steel pipe straightening equipment further includes a support frame, on which are provided:

[0038] At least two sets of symmetrically distributed clamping and conveying assemblies are provided, the clamping and conveying assemblies being used for axial feeding and positioning of the steel pipe, and multiple roller straightening assemblies being provided between the clamping and conveying assemblies, the roller straightening assemblies being used for straightening the steel pipe.

[0039] Preferably, the steel pipe straightening equipment further includes a lifting clearance hole penetrating the bearing base and a lifting assembly located at the bottom of the bearing base, wherein the bearing base is provided with a vertical lifting clearance hole penetrating the bearing base;

[0040] The lifting assembly includes a slide block installed at the bottom of the support base and having slide rails on both sides of the inner wall, a lifting platform slidably installed on the slide rails, and a screw drive mechanism that drives the lifting platform to slide along the slide rails;

[0041] The screw drive mechanism includes a servo motor and a ball screw pair. The ball screw pair includes a ball screw and a sliding block. The ball screw is rotatably connected to the slide block. The servo motor is connected to the ball screw to drive the ball screw to rotate. The sliding block on the ball screw is fixedly connected to the lifting platform.

[0042] A first hydraulic rod is fixed below the lifting platform. The piston rod of the first hydraulic rod passes vertically through the lifting platform and is connected to a floating mounting plate. A second hydraulic rod is fixed on the floating mounting plate. The piston rod of the second hydraulic rod is coaxially connected to the mandrel. A guide column is fixed at the bottom of the floating mounting plate. The bottom end of the guide column passes through the lifting platform and is slidably connected to it. A support slide is fixed on the floating mounting plate. The support slide is slidably connected to the mandrel.

[0043] This application also provides a straightening process for a steel pipe straightening device, the process including the following steps:

[0044] S1, Adaptive clamping and conveying

[0045] Drive the steel pipe to feed axially;

[0046] S2, Guiding component forming

[0047] The action winding assembly pulls multiple sleeves to be inserted and positioned in sequence, forming a straight cylindrical structure that is coaxial and rigid with the steel pipe;

[0048] S3, Internal Support Positioning

[0049] The straight cylindrical structure is pushed into the inner cavity of the steel pipe;

[0050] S4, Dynamic Heating

[0051] The action winding assembly connects multiple sleeves to form a flexible straight cylinder structure. The heating module moves with the sleeves into the inside of the steel pipe and adaptively adjusts its position according to the degree of bending of the steel pipe to perform circumferential heating of the inner wall of the target area.

[0052] S5. Repair of dents in the inner wall of steel pipes

[0053] The repair head adaptively adjusts its position according to the degree of bending of the steel pipe, and squeezes the inner wall of the steel pipe from the inside out to repair the dented area on the inner wall of the steel pipe, thus completing the dent repair.

[0054] S6, Straightening and Inner Circle Finishing

[0055] The outer wall of the steel pipe is straightened and residual deformation is eliminated, and the inner wall of the steel pipe is finished rounded using an inner round finishing head.

[0056] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0057] The steel pipe straightening process repairs dents by heating the inside of the pipe and pressing the dented areas from within. This reduces operational complexity, energy waste, and manufacturing costs. The heating method, which heats the pipe from the inside out, effectively minimizes radial temperature differences, ensuring synchronized temperature increases across the entire pipe section. Furthermore, the temperature standard deviation in the straightening area is lower than in traditional processes, mitigating the risk of localized overheating or insufficient plasticity caused by uneven temperature distribution. Attached Figure Description

[0058] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained from these drawings without creative effort.

[0059] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0060] Figure 2 This is a schematic diagram of the installation structure of the lifting platform of the present invention;

[0061] Figure 3 This is a schematic diagram of the installation structure of the conveyor roller of the present invention;

[0062] Figure 4 This is a schematic diagram of the installation structure of the straightening roller of the present invention;

[0063] Figure 5 This is a schematic diagram of the installation structure of the slide bar part of the present invention;

[0064] Figure 6 This is a schematic diagram of the installation structure of the guide wheel of the present invention;

[0065] Figure 7 This is a schematic diagram of the installation structure of the repair head and the inner circle finishing head of the present invention;

[0066] Figure 8 This is a schematic diagram of the installation structure of the fixing block of the present invention;

[0067] Figure 9 This is a schematic diagram of the heating module of the present invention;

[0068] Figure 10 This is a schematic diagram of the installation structure of the mounting base portion of the present invention;

[0069] Figure 11 This is a schematic diagram of the assembly structure of the sleeve of the present invention;

[0070] Figure 12 This is a schematic diagram of the internal structure of the sleeve of the present invention.

[0071] Explanation of the labels in the diagram:

[0072] 1. Support frame; 2. First support plate; 201. Second support plate; 3. First bracket; 301. Second bracket; 4. First stepper motor; 401. Second stepper motor; 5. First drive shaft; 501. Second drive shaft; 6. Conveyor roller; 7. First slide bar; 701. Second slide bar; 8. Limit sleeve; 9. First spring; 10. Hydraulic cylinder; 11. Straightening roller; 12. Lifting clearance hole; 13. Slide block; 14. Slide rail; 15. Lifting platform; 16. Ball screw; 17. Servo motor; 18. First hydraulic rod; 19. Floating mounting plate; 20. Guide column; 21. Second hydraulic rod; 22. Support slide; 23. Core rod; 24. Fixing block; 5. Hinge base; 26. First rotating shaft; 27. Torsion spring; 28. Support arm; 29. ​​Second rotating shaft; 30. Guide wheel; 31. Repair head; 32. Heating module; 321. Heating element; 322. Heat insulation sleeve; 323. Limiting rod; 324. Limiting ring; 325. Second spring; 326. Bracket; 327. Positioning wheel; 33. Mounting base; 34. Shaft support; 35. Reel; 36. Spacer; 37. Asynchronous motor; 38. Gear; 39. Rope; 40. Sleeve; 41. Slider; 42. Movable cavity; 43. Flange; 44. Positioning end; 45. Positioning groove; 46. Mounting groove; 47. Spring; 48. Slot; 49. Inner circle finishing head. Detailed Implementation

[0073] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, not all of them. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application. The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0074] like Figures 7-12 As shown, a steel pipe straightening device includes a mandrel 23, a guide assembly, a repair head 31, an inner round finishing head 49, a winding assembly, and a heating module;

[0075] The guide assembly includes multiple sleeves 40 that are inserted sequentially along the axis, with the last sleeve 40 being fixedly connected to the mandrel 23.

[0076] The winding assembly is connected to the guiding assembly so that the multiple sleeves 40 of the guiding assembly are connected to form a rigid or flexible cylindrical structure.

[0077] The heating module 32 is disposed on the outer surface of the sleeve 40 and located in front of the repair head 31, and is used to heat the inner wall of the steel pipe;

[0078] The repair head 31 is installed on the sleeve 40 and can move into the steel pipe along with the sleeve 40; the repair head 31 squeezes and repairs the concave area of ​​the steel pipe (which appears as a convex shape when viewed from inside the steel pipe), thereby improving the stability of the steel pipe during the straightening process and preventing fatigue cracks from occurring in the steel pipe during the straightening process.

[0079] The inner round finishing head 49 is mounted on the mandrel 23; it can follow the mandrel 23 into the steel pipe to finish the inner wall of the steel pipe.

[0080] In this embodiment, the repair head 31 and the inner circle finishing head 49 can be adapted and replaced according to the inner circle size of the steel pipe.

[0081] Specifically, one end of the sleeve 40 is the first end, and the other end of the sleeve 40 is the second end. The sleeve 40 includes a positioning groove 45 disposed at the first end and a positioning end 44 formed at the second end. The sleeve 40 is provided with a movable cavity 42 and a slot 48 in the shape of a frustum and adapted to the shape of the positioning end 44 in sequence along the axial direction. The slot 48 is connected to the movable cavity 42, and the movable cavity 42 is connected to the positioning groove 45. The positioning groove 45 is a conical groove. At least two mounting grooves 46 are provided on the conical surface of the positioning groove 45 in the circumferential direction. Each mounting groove 46 is provided with an elastic abutment.

[0082] The outer wall of the second end of the sleeve 40 is provided with an annular flange 43, which forms a clearance fit with the movable cavity 42;

[0083] When two adjacent sleeves 40 are connected, the annular flange 43 on the front sleeve 40 enters from the positioning groove 45 and is fitted into the movable cavity 42, and the positioning end 44 on the front sleeve 40 is fitted into the slot 48; wherein, the outer circle of the annular flange 43 has a gap with the peripheral wall of the movable cavity 42, and the axial width of the annular flange 43 is smaller than the axial width of the movable cavity 42.

[0084] The annular flange 43 and the movable cavity 42 can connect adjacent sleeves 40 together, and when they are inserted into each other, the positioning end 44 and the positioning groove 45 can be accurately aligned.

[0085] Two sliders 41 are symmetrically arranged on the outer surface of the sleeve 40, and the corresponding sliders 41 on the outside of the sleeve 40 are arranged along the axial direction.

[0086] The winding assembly includes a mounting base 33 fixed to the foremost sleeve 40, two ropes 39, a drive assembly that controls the synchronous winding and unwinding of the ropes 39, and at least two elastic telescopic mechanisms.

[0087] The rear ends of the two ropes 39 are respectively fixedly connected to the fixing blocks 24, which are installed on the core rod 23. The front ends of the two ropes 39 pass through the corresponding sliders 41 and are connected to the drive assembly. The sliders 41 limit the sleeve 40.

[0088] The flexible telescopic mechanism is adapted to slide along the inner wall of the steel pipe and provide radial support for the guide assembly.

[0089] In this embodiment, the design of inserting multiple sleeves in sequence allows for a certain amount of movable space between the sleeves 40, increasing the range of adaptable lengths. The annular flange 43 is engaged in the movable cavity 42 and has a certain degree of freedom with respect to the movable cavity 42, which can improve the smoothness of extension and retraction and avoid deflection and jamming.

[0090] In some embodiments, such as Figure 11 As shown, the elastic abutment is a metal spring 47. The fixed end of the spring 47 is embedded in the mounting groove 46, and the free end extends in the direction of the axis of the sleeve 40 to provide elastic force for the axial relative movement of adjacent sleeves 40.

[0091] The elastic force released by the spring 47 allows the adjacent sleeves 40 to have a certain degree of elastic freedom when connected in a non-rigid straight cylindrical structure.

[0092] In some embodiments, such as Figure 10 As shown, the drive assembly includes an asynchronous motor 37 fixed to the end of the mounting base 33, two shaft supports 34 fixed to the mounting base 33, a reel 35 rotatably connected between the two shaft supports 34, and gears 38 fixed to the output end of the asynchronous motor 37 and the end of the reel 35 respectively.

[0093] A spacer 36 is fixedly provided in the middle of the scroll 35 to separate the two ropes 39;

[0094] The two gears 38 mesh with each other;

[0095] The front ends of the two ropes 39 are respectively wrapped around the outer wall of the spool 35 on both sides of the spacer 36, and after passing through the rope hole of the mounting base 33, they pass through the corresponding slider 41 and extend to the fixing block 24.

[0096] In some embodiments, such as Figure 6 and Figure 8 As shown, the elastic telescopic mechanism includes a hinged base 25 fixed to the outer wall of the sleeve 40 and elastic reset units symmetrically arranged at both ends of the hinged base 25.

[0097] The elastic reset unit includes a first rotating shaft 26 rotatably connected to the hinge base 25, a torsion spring 27 sleeved on the first rotating shaft 26, a support arm 28 fixed on the first rotating shaft 26, and a guide wheel 30 rotatably connected to the support arm 28.

[0098] One end of the torsion spring 27 is connected to the first rotating shaft 26, and the other end of the torsion spring 27 is connected to the hinged base 25.

[0099] The guide wheel 30 is rotatably connected to the end of the support arm 28 via the second rotating shaft 29, and the guide wheel 30 rolls along the axis of the steel pipe.

[0100] In this embodiment, the support arm 28 of the elastic support assembly expands radially under the preload of the torsion spring 27, causing the guide wheel 30 to roll axially against the inner wall of the steel pipe, supporting the straight cylindrical structure composed of multiple sleeves 40, which facilitates the rapid movement of the straight cylindrical structure into the steel pipe.

[0101] In some embodiments, such as Figure 9 As shown, the heating module 32 includes an annular heating body 321, a heat insulation sleeve 322 connected to the end of the heating body 321, and at least two elastic positioning units evenly distributed circumferentially on the heat insulation sleeve 322.

[0102] The heat insulation sleeve 322 uses zirconia ceramic fiber (temperature resistance > 1200℃) as the inner layer and is covered with aerogel heat insulation felt (thermal conductivity < 0.02W / m·K) on the outer layer. It is fixed to the outer wall of the sleeve 40 by bolt connection. An aluminum foil reflective layer is added between the heating body 321 and the heat insulation sleeve 322 to reflect the infrared radiation heat back to the inner wall of the steel pipe.

[0103] The surface of the annular heating element 321 maintains a heat conduction distance from the inner wall of the steel pipe;

[0104] The heat insulation sleeve 322 is fixedly connected to the sleeve 40;

[0105] In some embodiments, such as Figure 9 As shown, each elastic positioning unit includes a limiting rod 323 that passes through the heat insulation sleeve 322 and slides therewith, a wheel bracket 326 fixed to the end of the limiting rod 323, a second spring 325 sleeved on the limiting rod 323, and a limiting ring 324 disposed at the end of the limiting rod 323.

[0106] The heat insulation sleeve 322 can restrict the circumferential rotation of the limiting rod 323;

[0107] The wheeled bracket 326 has a rotatable positioning wheel 327 inside;

[0108] The two ends of the second spring 325 abut against the heat insulation sleeve 322 and the bracket 326 respectively;

[0109] The limiting ring 324 is used to limit the maximum extension displacement of the limiting rod 323.

[0110] In this embodiment, the limiting rod 323 of the elastic positioning unit retracts radially under the elastic force of the second spring 325, automatically adjusting according to the inner diameter of the steel pipe. The positioning wheel 327 supports and positions the annular heating body 321, ensuring that the heating body 321 is located radially near the middle of the steel pipe, so as to heat the inner wall of the pipe evenly.

[0111] In some embodiments, such as Figures 1-6 As shown, the steel pipe straightening equipment also includes a bearing base frame 1, on which at least two sets of symmetrically distributed clamping and conveying assemblies are provided. The clamping and conveying assemblies are used for axial feeding and positioning of the steel pipe.

[0112] Multiple roller straightening assemblies are provided between the clamping and conveying assemblies. The roller straightening assemblies are used for straightening steel pipes.

[0113] The steel pipe straightening equipment also includes a lifting assembly located at the bottom of the bearing base 1;

[0114] The support frame 1 is provided with a vertical lifting clearance hole 12 that penetrates the support frame 1;

[0115] The lifting assembly includes a slide block 13 installed at the bottom of the support base 1 and having slide rails 14 on both sides of the inner wall, a lifting platform 15 slidably installed on the slide rails 14, and a screw drive mechanism for driving the lifting platform 15 to slide along the slide rails 14.

[0116] The screw drive mechanism includes a servo motor 17 and a ball screw pair. The ball screw pair includes a ball screw 16 and a sliding block. The ball screw 16 is rotatably connected to the slide block 13. The servo motor 17 is connected to the ball screw 16 to drive the ball screw 16 to rotate. The sliding block on the ball screw 16 is fixedly connected to the lifting platform 15.

[0117] A first hydraulic rod 18 is fixed below the lifting platform 15, and its piston rod vertically penetrates the lifting platform 15 and is connected to a floating mounting plate 19. A second hydraulic rod 21 is fixed on the floating mounting plate 19, and its piston rod is coaxially connected to the mandrel 23. A guide column 20 is fixed at the bottom of the floating mounting plate 19, and the bottom end of the guide column 20 penetrates the lifting platform 15 and is slidably connected to it. A support slide 22 is fixed on the floating mounting plate 19, and the support slide 22 is slidably connected to the mandrel 23.

[0118] The asynchronous motor 37 drives the rope 39 to wind up, the servo motor 17 and the second hydraulic rod 21 start at the same time, the servo motor 17 drives the ball screw 16 to rotate, the lifting platform 15 moves away from the end of the steel pipe, and at the same time the second hydraulic rod 21 drives the straight cylinder structure to move. This design can quickly remove the straight cylinder structure from the steel pipe.

[0119] Furthermore, the first hydraulic rod 18 drives the floating mounting plate 19 to move below the lifting clearance hole 12, moving the straight cylinder structure below the bearing base frame 1, which facilitates the removal of the straightened steel pipe.

[0120] The clamping and conveying assembly includes two first support plates 2. Two first brackets 3 are provided on the opposite side of the two first support plates 2. A first stepper motor 4 is fixed on the top of the first bracket 3. A first drive shaft 5 rotates on the inner wall of the first bracket 3. A conveying roller 6 is fixed on the outer wall of the first drive shaft 5. Two first slide rods 7 are fixed on the side of the first bracket 3 near the first support plate 2. The ends of the first slide rods 7 pass through the first support plate 2 and are slidably connected to it. A first spring 9 is sleeved on the outer wall of the first slide rod 7. A limit sleeve 8 is fixed on the outer wall of the first slide rod 7. One end of the first spring 9 abuts against the first bracket 3 and the other end abuts against the first support plate 2.

[0121] The roller straightening assembly includes two second support plates 201. Two second brackets 301 are provided on the opposite side of the two second support plates 201. A second stepper motor 401 is fixed to the top of the second bracket 301. A second drive shaft 501 rotates on the inner wall of the second bracket 301. A straightening roller 11 is fixed to the outer wall of the second drive shaft 501. Two second slide rods 701 are fixed on the side of the second bracket 301 near the second support plate 201. The ends of the second slide rods 701 pass through the second support plate 201 and are slidably connected to it. A hydraulic cylinder 10 is fixed to the outer wall of both second support plates 201.

[0122] In one embodiment, the roller straightening assembly can be configured as multiple sets, arranged alternately in sequence. The straightening roller 11 on one roller straightening assembly can be arranged in the horizontal direction, and the straightening roller 11 on another roller straightening assembly can be arranged in the vertical direction. After the steel pipe to be straightened is straightened in the horizontal direction, it is straightened in the vertical direction.

[0123] like Figure 1-12 As shown, a straightening process for steel pipes includes the following steps:

[0124] S1, Adaptive clamping and conveying

[0125] The steel pipe is placed into the clamping station of the clamping and conveying assembly. The clamping and conveying assembly adaptively adjusts the clamping force according to the outer diameter of the steel pipe, and drives the steel pipe to feed axially.

[0126] S2, Guiding component forming

[0127] The asynchronous motor 37 is started to synchronously wind up the double rope 39, and pulls multiple sleeves 40 to be inserted and positioned in sequence to form a straight cylindrical structure that is coaxial and rigid with the steel pipe.

[0128] S3, Internal Support Positioning

[0129] The straight cylinder structure is pushed into the inner cavity of the steel pipe by the second hydraulic rod 21. The support arm 28 of the elastic support component is radially extended under the pre-tightening force of the torsion spring 27, so that the guide wheel 30 rolls axially against the inner wall of the steel pipe.

[0130] S4, Dynamic Heating

[0131] The asynchronous motor 37 releases the rope 39, and the elastic abutment drives the adjacent sleeve 40 to generate a directional deflection gap. The heating module 32 moves with the sleeve 40 into the inside of the steel pipe and adaptively adjusts its position according to the degree of bending of the steel pipe to perform circumferential heating of the inner wall of the target area.

[0132] S5. Repair of dents in the inner wall of steel pipes

[0133] The repair head 31 adaptively adjusts its position according to the degree of bending of the steel pipe, and squeezes the inner wall of the steel pipe from the inside to the outside to repair the dented area on the steel pipe, thus completing the dent repair.

[0134] S6, Straightening and Inner Circle Finishing

[0135] The outer wall of the steel pipe is straightened by a roller straightening assembly to eliminate residual deformation, and the inner wall of the steel pipe is finished by an inner round finishing head 49.

[0136] Traditional straightening equipment lacks the ability to couple and control multiple physical fields, making it impossible to integrate straightness correction and steel pipe dent repair. It requires the use of specialized shaping equipment to perform hot-pressing correction on the dented areas of the steel pipe, and then transfer it to the straightening unit for secondary heating and straightening after it cools to room temperature. This separate processing method increases the complexity of the operation and requires repeated heating of the steel pipe with long intervals, resulting in energy waste and increased manufacturing costs.

[0137] In this invention, the above-mentioned steel pipe straightening process first heats the inside of the steel pipe and then performs an extrusion repair on the concave area of ​​the steel pipe from the inside out, thereby repairing the concave structure of the steel pipe, reducing the complexity of the operation, reducing energy waste, and lowering manufacturing costs.

[0138] In this process, heating the steel pipe from the inside out effectively reduces the radial temperature difference, enabling the temperature of the entire cross-section of the steel pipe to be raised synchronously. Furthermore, the temperature standard deviation in the straightening area is lower than that of the traditional process, which can suppress local overheating or insufficient plasticity caused by uneven temperature to a certain extent.

[0139] If the concave areas of the steel pipe are not repaired before straightening, direct straightening will generate "tensile-compressive bipeak stress" in the concave areas, which can easily induce fatigue cracks. Furthermore, the concave areas will cause discontinuous contact between the straightening roller 11 and the steel pipe, resulting in straightness errors. In this invention, the stress in the concave area is converted into uniform compressive stress through concave repair, reducing the overall stress fluctuation amplitude and the resulting straightness errors.

[0140] In addition, in traditional processes, cold rolling may cause metal lattice distortion and microcracks; however, in this invention, dynamic heating to 300-450℃ puts the metal in a semi-plastic state, which can reduce straightening stress to a certain extent.

[0141] Traditional dent repair methods involve external hammering or rolling to force flatten the surface, which can lead to scratches on the outer surface and stress concentration on the inner wall. In contrast, this invention uses circumferential heating of the inner wall and the repair head 31 to push and press the repair from the inside out, which can avoid scratches on the steel pipe surface.

[0142] In some embodiments, in step S4, the heating temperature of the heating module is 300-450°C, and the heating time t can be set as required.

[0143] Working principle: The steel pipe is placed into the clamping position of the clamping and conveying assembly. The clamping and conveying assembly adaptively adjusts the clamping force according to the outer diameter of the steel pipe, driving the steel pipe to feed axially.

[0144] The asynchronous motor 37 is started, which drives the reel 35 to rotate through the gear 38, and simultaneously winds up the double rope 39, causing adjacent sleeves 40 to press against each other. The positioning end 44 is inserted into the slot 48, so that multiple sleeves 40 are inserted and positioned in sequence to form a rigid straight cylindrical structure coaxial with the steel pipe. Lubricant can be sprayed on the outer wall surface of the repair head 31 and the inner circle finishing head 49 to facilitate pressing.

[0145] The straight cylinder structure is pushed into the inner cavity of the steel pipe by the second hydraulic rod 21. The support arm 28 of the elastic support component moves radially under the preload of the torsion spring 27, so that the guide wheel 30 rolls axially against the inner wall of the steel pipe to support the straight cylinder structure.

[0146] Under the elastic force of the second spring 325, the limiting rod 323 of the elastic positioning unit retracts radially to adapt to the inner diameter of the steel pipe, so that the positioning wheel 327 rolls axially against the inner wall of the steel pipe, supporting the annular heating body 321 and ensuring that the heating body 321 is located in the radial direction near the middle of the steel pipe, so as to heat the inner wall of the steel pipe evenly.

[0147] The asynchronous motor 37 releases the rope 39, the metal spring 47 releases its elasticity, the positioning end 44 moves from the positioning groove 45, a directional deflection gap can be generated between adjacent sleeves 40, the heating module 32 can move with the sleeve 40 to the inside of the steel pipe and adaptively adjust its position to implement circumferential heating of the inner wall of the target area.

[0148] During axial feeding, the repair head 31 presses the inner wall of the steel pipe from the inside out before the steel pipe is straightened, repairing the dented area of ​​the steel pipe. Alternatively, the drive sleeve 40 can drive the repair head 31 to slide along the inside of the heated steel pipe, pressing the inner wall of the steel pipe from the inside out to repair the dented area of ​​the steel pipe, thus completing the dent repair.

[0149] After the dent repair is completed, the inner round finishing head 49 fixed on the mandrel 23 squeezes the inner wall of the steel pipe during the movement of the steel pipe to complete the finishing round of the inner wall of the steel pipe; the hydraulic cylinder 10 can push the second support plate 201 to move according to the size of the steel pipe, thereby pushing the second bracket 301 to move, so that the straightening roller 11 contacts the outer wall of the steel pipe, and the second stepper motor 401 drives the straightening roller 11 to rotate to squeeze and straighten the outer wall of the steel pipe;

[0150] After the steel pipe is straightened, the asynchronous motor 37 drives the rope 39 to wind up, the servo motor 17 and the second hydraulic rod 21 start simultaneously, the servo motor 17 drives the ball screw 16 to rotate, the lifting platform 15 moves away from the end of the steel pipe, and at the same time the second hydraulic rod 21 moves the straight cylinder structure, the repair head 31 and the inner circle finishing head 49 out of the steel pipe, and the first hydraulic rod 18 drives the floating mounting plate 19 to move below the lifting clearance hole 12, moving the straight cylinder structure below the bearing base frame 1.

[0151] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely preferred examples and are not intended to limit the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A steel pipe straightening device, characterized in that, Includes mandrel, guide assembly, repair head, inner round finishing head, winding assembly and heating module; The guide assembly includes multiple sleeves that are inserted sequentially along the axis, with the last sleeve being fixedly connected to the mandrel. The winding assembly is connected to the guiding assembly so that the multiple sleeves of the guiding assembly are connected to form a rigid or flexible cylindrical structure. The heating module is disposed on the outer surface of the sleeve and located in front of the repair head, and is used to heat the inner wall of the steel pipe; The repair head is mounted on the sleeve and is adapted to move into the steel pipe along with the sleeve. The inner circle finishing head is mounted on the mandrel and is adapted to move with the mandrel into the steel pipe to finish the inner wall of the steel pipe.

2. The steel pipe straightening equipment according to claim 1, characterized in that, One end of the sleeve is the first end, and the other end of the sleeve is the second end. The sleeve includes a positioning groove disposed at the first end and a positioning end formed at the second end. A movable cavity and a frustum-shaped slot adapted to the shape of the positioning end are sequentially disposed along the axial direction inside the sleeve. The slot is connected to the movable cavity, and the movable cavity is connected to the positioning groove. The positioning groove is a conical groove. At least two mounting grooves are opened on the conical surface of the positioning groove along the circumferential direction. Each mounting groove is provided with an elastic abutment. The outer wall of the second end of the sleeve is provided with an annular flange, and the annular flange forms a clearance fit with the movable cavity.

3. The steel pipe straightening equipment according to claim 2, characterized in that, Two sliders are symmetrically arranged on the outer surface of the sleeve, and the corresponding sliders on the outside of the sleeve are arranged axially. The winding assembly includes a mounting base fixed to the sleeve at the front end, two ropes, a drive assembly that controls the synchronous winding and unwinding of the ropes, and at least two elastic telescopic mechanisms. The rear ends of the two ropes are respectively fixedly connected to a fixing block, which is mounted on the mandrel. The front ends of the two ropes pass through the corresponding sliders and are connected to the drive assembly. The sliders limit the position of the sleeve. The elastic telescopic mechanism is adapted to slide along the inner wall of the steel pipe and provide radial support for the guide assembly.

4. The steel pipe straightening equipment according to claim 3, characterized in that, The elastic abutment is a metal spring sheet. The fixed end of the spring sheet is embedded in the mounting groove, and the free end of the spring sheet extends towards the sleeve axis to provide elastic force for the axial relative movement of adjacent sleeves.

5. The steel pipe straightening equipment according to claim 3, characterized in that, The driving component includes: An asynchronous motor fixed to the end of the mounting base; Two shaft supports fixed to the mounting base; A rotatable reel is connected between the two shaft supports, and a spacer is fixedly provided in the middle of the reel to separate the two ropes; Gears are respectively fixed to the output end of the asynchronous motor and the end of the reel, and the two gears mesh with each other; The front ends of the two ropes are respectively wrapped around the outer wall of the reel on both sides of the spacer, and after passing through the rope hole of the mounting base, they pass through the corresponding slider and extend to the fixing block.

6. The steel pipe straightening equipment according to claim 3, characterized in that: The elastic telescopic mechanism includes: A hinged base fixed to the outer wall of the sleeve; The elastic reset units are symmetrically arranged at both ends of the hinge base. Each elastic reset unit includes a first rotating shaft rotatably connected to the hinge base, a torsion spring sleeved on the first rotating shaft, a support arm fixed on the first rotating shaft, and a guide wheel rotatably connected to the support arm. One end of the torsion spring is connected to the first rotating shaft, and the other end of the torsion spring is connected to the hinge base; The guide wheel is rotatably connected to the end of the support arm via a second rotating shaft, and the guide wheel rolls along the axis of the steel pipe.

7. The steel pipe straightening equipment according to claim 1, characterized in that: The heating module includes: A ring-shaped heating element, wherein the surface of the heating element maintains a heat conduction distance from the inner wall of the steel pipe; A heat insulation sleeve is connected to the end of the heating element, and the heat insulation sleeve is fixedly connected to the sleeve tube; At least two elastic positioning units are circumferentially distributed on the heat insulation sleeve, each elastic positioning unit comprising: A limiting rod that penetrates the heat insulation sleeve and slides therewith; A wheel bracket fixed to the end of the limiting rod, wherein a positioning wheel is rotatably connected inside the wheel bracket; A second spring is sleeved on the limiting rod, and the two ends of the second spring abut against the heat insulation sleeve and the wheel bracket, respectively; A limiting ring is provided at the end of the limiting rod, and the limiting ring is used to limit the maximum extension displacement of the limiting rod.

8. The steel pipe straightening equipment according to claim 1, characterized in that: It also includes a support frame, on which are provided: At least two sets of symmetrically distributed clamping and conveying assemblies are provided, the clamping and conveying assemblies being used for axial feeding and positioning of the steel pipe, and multiple roller straightening assemblies being provided between the clamping and conveying assemblies, the roller straightening assemblies being used for straightening the steel pipe.

9. The steel pipe straightening equipment according to claim 8, characterized in that: It also includes a lifting clearance hole penetrating the support base frame and a lifting assembly located at the bottom of the support base frame, wherein the support base frame is provided with a vertical lifting clearance hole penetrating the support base frame; The lifting assembly includes a slide block installed at the bottom of the support base and having slide rails on both sides of the inner wall, a lifting platform slidably installed on the slide rails, and a screw drive mechanism that drives the lifting platform to slide along the slide rails; The screw drive mechanism includes a servo motor and a ball screw pair. The ball screw pair includes a ball screw and a sliding block. The ball screw is rotatably connected to the slide block. The servo motor is connected to the ball screw to drive the ball screw to rotate. The sliding block on the ball screw is fixedly connected to the lifting platform. A first hydraulic rod is fixed below the lifting platform. The piston rod of the first hydraulic rod passes vertically through the lifting platform and is connected to a floating mounting plate. A second hydraulic rod is fixed on the floating mounting plate. The piston rod of the second hydraulic rod is coaxially connected to the mandrel. A guide column is fixed at the bottom of the floating mounting plate. The bottom end of the guide column passes through the lifting platform and is slidably connected to it. A support slide is fixed on the floating mounting plate. The support slide is slidably connected to the mandrel.

10. A straightening process for a steel pipe straightening device as described in any one of claims 1 to 9, characterized in that, The process includes the following steps: S1, Adaptive clamping and conveying Drive the steel pipe to feed axially; S2, Guiding component forming The action winding assembly pulls multiple sleeves to be inserted and positioned in sequence, forming a straight cylindrical structure that is coaxial and rigid with the steel pipe; S3, Internal Support Positioning The straight cylindrical structure is pushed into the inner cavity of the steel pipe; S4, Dynamic Heating The action winding assembly connects multiple sleeves to form a flexible straight cylinder structure. The heating module moves with the sleeves into the inside of the steel pipe and adaptively adjusts its position according to the degree of bending of the steel pipe to perform circumferential heating of the inner wall of the target area. S5. Repair of dents in the inner wall of steel pipes The repair head adaptively adjusts its position according to the degree of bending of the steel pipe, and squeezes the inner wall of the steel pipe from the inside out to repair the dented area on the inner wall of the steel pipe, thus completing the dent repair. S6, Straightening and Inner Circle Finishing The outer wall of the steel pipe is straightened and residual deformation is eliminated, and the inner wall of the steel pipe is finished rounded using an inner round finishing head.

Images