Automatic prewelding error edge adjusting mechanism for straight-seam rectangular welded pipe

Abstract

The utility model relates to straight seam rectangular welded pipe manufacturing technical field, concretely to a kind of straight seam rectangular welded pipe automatic prewelding misalignment adjusting mechanism, including base, the placement plate being placed on base, the gantry being set on base and spanning at the both sides of placement plate, adjusting mechanism being set between gantry and placement plate, the edge compression mechanism being set at the both sides of gantry bottom portion.The device is cooperated with multiple groups vertical side edge compression roller by double-side C-shaped frame, and the rectangular pipe is clamped evenly from both sides, then combined with top flat compression roller constraint, four side walls are synchronously centered, the special-shaped cross-section characteristics of rectangular pipe are adapted, the problem of jointing not strictly appears when existing circular pipe equipment adapts rectangular pipe is avoided.Laser displacement sensor is used to detect misalignment amount in real time, and the second oil cylinder is interlocked by PLC controller, so that L-shaped swing arm drives main flat roller to be adjusted in a targeted manner, which is fast in response and stable in accuracy, and solves the problems of manual adjustment lag and high labor intensity.

Description

Technical Field

[0001] This utility model relates to the field of straight seam rectangular welded pipe manufacturing technology, specifically to an automatic pre-welding misalignment adjustment mechanism for straight seam rectangular welded pipe. Background Technology

[0002] Straight-seam rectangular tubes, with their advantages of regular cross-section, uniform stress, and high space utilization, are widely used in various fields such as machinery manufacturing, construction engineering, and pipeline transportation. During their production, after the strip steel is unpacked, flattened, pre-bent, and formed, it needs to undergo a pre-welding process to fix the tube seam. The quality of the pre-welding directly determines the structural strength, sealing performance, and appearance accuracy of the finished tube. Among these, weld misalignment is one of the most critical quality risks in the pre-welding process.

[0003] Weld misalignment arises from the superposition of multiple process errors: dimensional deviations during strip pre-bending, insufficient positional adjustment precision of the seam rollers, uneven stress distribution in the tube blank, and centering deviations during transport. All of these can lead to vertical misalignment of the steel strips on both sides of the weld seam in the tube blank. Once the misalignment exceeds the allowable range, it will directly cause incomplete welds and poor fusion, not only reducing the overall load-bearing capacity and corrosion resistance of the rectangular tube, but also affecting the smooth progress of subsequent shaping, precision welding, and other processes, and in severe cases, leading to product downgrading or scrapping.

[0004] Existing technologies for handling misaligned edges in pre-welded straight seam pipes have significant limitations. Early methods relied heavily on manual adjustment of the seam-jointing rollers, with operators relying on experience to judge the misalignment and make adjustments intermittently. This resulted in problems such as adjustment lag, unstable accuracy, and high labor intensity, failing to meet the high-efficiency requirements of automated production lines. Some automated adjustment devices are primarily designed for circular steel pipes. For example, Chinese Patent No. CN209886870U discloses a welding device for straight seam steel pipes, which uses a positioning mechanism to clamp the pipe and drive the welding torch to move and weld. However, it lacks a dedicated misalignment detection and correction component, and its positioning structure is adapted to circular cross-sections, making it difficult to handle the irregular cross-section characteristics of rectangular pipes. It cannot effectively constrain the synchronous alignment and misalignment adjustment of the four side walls of the rectangular pipe, easily leading to insufficient flatness of the steel strips on both sides of the weld, resulting in defects such as incomplete jointing and open welds.

[0005] In addition, the few existing automatic adjustment mechanisms for weld misalignment either have problems such as the adjustment point being far from the misalignment area and slow response speed, or poor adaptability due to complex structure, making it difficult to meet the production needs of rectangular tubes of different specifications. Furthermore, the adjustment accuracy is greatly affected by the cross-sectional shape of the tube, and cannot meet the process requirements of high-precision pre-welding.

[0006] Therefore, developing a pre-welding misalignment adjustment mechanism that is adaptable to the irregular cross-sectional characteristics of straight seam rectangular tubes, has precise adjustment capabilities, rapid response, and a high degree of automation is crucial for solving existing technical pain points and improving the production quality and efficiency of straight seam rectangular tubes, and has significant industry application value. Utility Model Content

[0007] The purpose of this invention is to provide an automatic pre-welding misalignment adjustment mechanism for straight-seam rectangular welded pipes, which solves the problems mentioned in the prior art in the background section.

[0008] To achieve the above objectives, this utility model provides the following technical solution: an automatic pre-welding misalignment adjustment mechanism for straight-seam rectangular welded pipes, comprising a base, a placement plate on the base, a gantry frame on the base spanning both sides of the placement plate, an adjustment mechanism between the gantry frame and the placement plate, and edge pressing mechanisms on both sides of the bottom of the gantry frame. The adjustment mechanism includes a horizontal plate connected to the output shaft of the lifting cylinder of the gantry frame and vertically slidingly engaged with the column of the gantry frame, a pressure head seat at the bottom of the horizontal plate, a first adjustment component and a second adjustment component on the pressure head seat, and a pre-pressing flat roller rotatably disposed on one side of the bottom of the pressure head seat. The edge pressing mechanism is used in conjunction with the first adjustment component and the second adjustment component.

[0009] Furthermore, the pressing mechanism includes a first hydraulic cylinder, a slide block, a C-shaped frame, and side pressure rollers; there are two of each of the first hydraulic cylinder, slide block, and C-shaped frame; mounting plates are provided on both sides of the bottom of the gantry frame; the two first hydraulic cylinders are respectively mounted on the two mounting plates; the two slide blocks are respectively located on both sides of the base and below the mounting plates; the two C-shaped frames are respectively connected to the output shafts of the two first hydraulic cylinders and their bottoms slide in cooperation with the slide blocks; and multiple side pressure rollers are provided and vertically symmetrically rotated and connected to the two C-shaped frames.

[0010] Furthermore, both the first adjustment assembly and the second adjustment assembly include a second hydraulic cylinder and an L-shaped swing arm; the two second hydraulic cylinders are symmetrically hinged to the bottom of the pressure head seat, and the ends of the horizontal sections of the two swing arms away from their vertical sections are symmetrically rotatably connected to one side of the middle of the pressure head seat; the ends of the horizontal sections of the two swing arms near their vertical sections are respectively rotatably connected to the output shafts of the two second hydraulic cylinders; and the bottom of the vertical sections of the two swing arms are rotatably connected to a main pressure roller.

[0011] Furthermore, two laser displacement sensors are symmetrically arranged at the bottom of the pressure head seat, and the two laser displacement sensors are arranged corresponding to the two main pressure rollers.

[0012] Furthermore, the two laser displacement sensors are interlocked with the two second hydraulic cylinders respectively via a PLC controller.

[0013] Furthermore, the lifting cylinder and the first cylinder are interlocked with the PLC controller.

[0014] The specific beneficial effects are as follows: 1. Adapts to irregular rectangular tube cross-sections, resolving compatibility issues: This device uses a double-sided C-shaped frame and multiple sets of vertical side pressure rollers to evenly clamp the rectangular tube from both sides. Combined with the constraint of the top flat pressure roller, it achieves synchronous centering of the four side walls, adapting to the irregular cross-sectional characteristics of the rectangular tube and avoiding the problem of poor joint sealing that occurs when adapting circular tube equipment to rectangular tubes.

[0015] 2. Automated and precise adjustments, replacing manual operation: This device uses a laser displacement sensor to detect the misalignment in real time, and interlocks with the second hydraulic cylinder through a PLC controller to drive the L-shaped swing arm to adjust the main pressure roller in a targeted manner. It has a rapid response and stable accuracy, solving the problems of slow manual adjustment and high labor intensity.

[0016] 3. Compatible with multiple production specifications, improving adaptability: The C-shaped frame of the pressing mechanism of this device can slide laterally along the slide block. The swing angle of the adjusting mechanism's swing arm and the vertical stroke of the lifting cylinder are both adjustable, which can adapt to rectangular tubes of different widths and heights, solving the problem of poor adaptability and difficulty in compatibility with multi-specification production of existing mechanisms.

[0017] 4. Ensure pre-welding quality and improve production efficiency: This device employs a continuous automated process of pre-pressing and leveling → real-time detection → precise adjustment → synchronous pre-welding to strictly control the misalignment within the allowable range, avoid defects such as incomplete welding and poor fusion, reduce product downgrading and scrapping, and simultaneously meet the high-efficiency operation requirements of automated production lines. Attached Figure Description

[0018] Figure 1 This is a structural diagram of the present utility model; Figure 2 This is a rear view of the present invention; Figure 3 This is a structural diagram of the adjustment mechanism of this utility model; Figure 4 This is a rear view of the adjustment mechanism of this utility model; Figure 5 This is a bottom view of the adjustment mechanism of this utility model; Figure 6 This is a cross-sectional view of the adjustment mechanism of this utility model; Figure 7 This is a system block diagram of the present invention.

[0019] In the diagram: 1. Base; 2. Placement plate; 3. Gantry frame; 4. Lifting cylinder; 5. Column; 6. Horizontal plate; 7. Press head seat; 8. Pre-pressing flat roller; 9. First cylinder; 10. Slide seat; 11. C-shaped frame; 12. Side pressure roller; 13. Mounting plate; 14. Second cylinder; 15. Swing arm; 16. Main pressure flat roller; 17. Laser displacement sensor. Detailed Implementation

[0020] The following is in conjunction with the appendix Figure 1-7 This document provides a detailed description of the specific implementation method of the automatic pre-welding misalignment adjustment mechanism for straight seam rectangular welded pipes according to the present invention. This embodiment is only used to explain the present invention and is not intended to limit the scope of protection of the present invention.

[0021] like Figure 1-7 As shown, the misalignment adjustment mechanism disclosed in this utility model is used to solve the problems of misalignment, low adjustment efficiency, and insufficient precision in the pre-welding process of straight-seam rectangular welded pipes. This device consists of a base 1, a placement plate 2, a gantry frame 3, an adjustment mechanism, and a pressing mechanism. Through the coordinated operation of the mechanical structure and the PLC control system, it achieves automatic positioning of the plate, real-time detection and precise adjustment of misalignment, and the overall mechanism exhibits strong stability and a high degree of automation. Specific implementation details are as follows: The base 1 is made of Q235 low-carbon steel plate, which has good rigidity and weldability. Its overall dimensions are 2000mm (length) × 800mm (width) × 50mm (thickness). It is formed by splicing and welding multiple steel plates, with four pre-drilled holes at the bottom for anchor bolts. It is fixed to the workshop floor with M24 high-strength bolts to ensure no displacement during operation. The top surface is ground to a flatness error controlled within 0.5mm / m, providing a level reference for subsequent component installation.

[0022] The placement plate 2 is made of Q235 steel plate with a thickness of 30mm and dimensions of 1800mm in length and 600mm in width, which fits the central area of ​​the top of the base 1. It is fixed to the base 1 by arc welding. A segmented symmetrical welding process is used during welding to avoid welding deformation. After welding, the surface is polished to ensure that the plate to be welded is placed stably.

[0023] The gantry frame 3 consists of four uprights 5 and a crossbeam. The uprights 5 are made of Q235 steel plate with a wall thickness of 10mm and a length of 1200mm. Two uprights 5 form a group, and the two groups of uprights 5 are symmetrically fixed to both sides of the base 1 by full welding. The crossbeam is made of Q235 steel plate welded into a rectangular beam structure with dimensions of 1200mm in length × 100mm in width × 80mm in height. The four corners are fixed to the tops of the four uprights 5 by full welding, and triangular reinforcing plates are added at the welds to enhance the overall load-bearing capacity. Each group of uprights 5 has a vertically welded slide rail along the inner wall of the opposite side. The slide rail is made of No. 45 steel plate with a thickness of 12mm and the surface is quenched to a hardness of HRC45-50 to improve sliding wear resistance.

[0024] The adjustment mechanism consists of a horizontal plate 6, a lifting cylinder 4, a pressure head seat 7, a pre-pressure flat roller 8, a first adjustment assembly, a second adjustment assembly, and a main pressure flat roller 16. Among them: The horizontal plate 6 is made of Q235 steel plate with dimensions of 1000mm in length, 200mm in width, and 20mm in thickness. Cast iron sliders are fixed on both sides by M16 bolts. The sliders slide in conjunction with the slide rails on the column 5. The sliders have lubrication grooves on the inside, and lubricating grease is added regularly to reduce friction.

[0025] The lifting cylinder 4 is a double-acting hydraulic cylinder with a diameter of 50mm and a stroke of 150mm. The cylinder body is welded to the upper part of the crossbeam of the gantry frame 3 through a bracket. The output shaft passes through the crossbeam and is connected to the top center of the cross plate 6 by bolts through a flange to ensure smooth power transmission.

[0026] The pressure head seat 7 is made of Q235 steel plate welded into a box-shaped structure with dimensions of 800mm in length × 150mm in width × 100mm in height. It is fixed to the bottom of the horizontal plate 6 with M20 high-strength bolts and has internal welded reinforcing ribs to improve its resistance to deformation.

[0027] The pre-compression flat roller 8 is made of GCr15 bearing steel, with a diameter of 80mm and a length of 200mm. After surface quenching, it is polished. Both ends are connected to the welded bracket at the bottom of the pressure head seat 7 through deep groove ball bearings. The outer ring of the bearing is interference-fitted with the bracket to ensure flexible rotation.

[0028] Both the first and second adjustment components consist of a second hydraulic cylinder 14 and an L-shaped swing arm 15. The second hydraulic cylinder 14 is a double-acting hydraulic cylinder of the same model as the lifting cylinder 4. The cylinder body is hinged to both sides of the bottom of the pressure head seat 7 via a hinged seat. The hinged seat is a machined part of Q235 steel plate with a thickness of 15mm and is fixed by full welding. The L-shaped swing arm 15 is made of Q235 steel plate by bending. The horizontal section is 300mm long × the vertical section is 200mm long × the thickness is 12mm. The end of the horizontal section away from the vertical section is rotatably connected to the welded support in the middle of the pressure head seat 7 via a pin and a bearing. The end of the horizontal section closer to the vertical section is hinged to the output shaft of the second hydraulic cylinder 14 via a pin.

[0029] The main pressure roller 16 and the pre-pressure roller 8 are made of the same material and have the same dimensions. They are rotatably connected to the welded bearing seat at the bottom of the vertical section of the swing arm 15 through a deep groove ball bearing to ensure smooth rolling when in contact with the plate.

[0030] The edge-pressing mechanism consists of a mounting plate 13, a first hydraulic cylinder 9, a slide block 10, a C-shaped frame 11, and side pressure rollers 12. Among them: Mounting plate 13 is made of Q235 steel plate with dimensions of 300mm in length, 100mm in width, and 15mm in thickness. It is fixed to a set of columns 5 on both sides of the bottom of the gantry frame 3 by full welding. Bolt holes are drilled on the surface for fixing the first hydraulic cylinder 9.

[0031] The first oil cylinder 9 and the second oil cylinder 14 are of the same model, the cylinder bodies are horizontally fixed on the outer side of the mounting plate 13 via M16 bolts, and the output shafts are arranged facing inward.

[0032] The sliding seat 10 is made of HT200 gray cast iron, with dimensions of 400mm in length × 100mm in width × 50mm in height, is fixed on both sides of the base 1 via M16 bolts, is located directly below the mounting plate 13, and is provided with a T-shaped sliding groove at the top, and the surface of the sliding groove is subjected to precision grinding treatment.

[0033] The C-shaped frame 11 is formed by welding Q235 steel plates, with the opening facing inward, a height of 300mm × a width of 200mm, the bottom is welded with a cast iron sliding block, the sliding block is in sliding fit with the T-shaped sliding groove of the sliding seat 10, and the middle part is bolted to the output shaft of the first oil cylinder 9 via a flange plate.

[0034] The side pressure rollers 12 are made of GCr15 bearing steel, with a diameter of 80mm × a length of 150mm, 3 to 5 of them are evenly arranged on each C-shaped frame 11 along the vertical direction, are rotatably connected to the welding bracket on the inner side of the C-shaped frame 11 through deep groove ball bearings, and the bracket spacing is 80mm, so as to ensure uniform compression on the side edge of the plate.

[0035] This device further involves a detection and control system, which is specifically composed of a laser displacement sensor 17 and a PLC controller. Wherein: There are two laser displacement sensors 17 in total, which are high-precision laser ranging sensors with a measuring range of 0-50mm and an accuracy of ±0.01mm, are welded on both sides of the bottom of the pressure head seat 7 through aluminum alloy brackets, the height of the brackets is 50mm, the sensor probes face downward and are in one-to-one correspondence with the two main flattening rollers 16, so as to ensure that the detection area covers the edge of the plate. The PLC controller adopts Siemens S7-200 SMART series PLC, which is installed in the cold-rolled steel plate electric control box on one side of the gantry 3, and the protection grade of the electric control box is IP54 to prevent dust and oil from entering. The laser displacement sensor 17 is connected to the PLC input module through a shielded signal line, and the second oil cylinder 14, the jacking oil cylinder 4, and the first oil cylinder 9 are respectively connected to the PLC output module through 4WE6Y-6X / EG24N9K4 type electromagnetic directional valves, so as to realize the linkage control of detection signals and actuators.

[0036] In use, the base 1 is first fixed to the ground, then the placement plate 2 and gantry 3 are welded in sequence. Next, the adjustment mechanism and edge pressing mechanism are installed. Finally, the laser displacement sensor 17 and electrical control box are assembled and connected. After assembly, grease is applied to all sliding parts, and the hydraulic system is vented. When the plate to be welded is placed on the placement plate 2, the PLC receives a start signal and controls the lifting cylinder 4 to descend, driving the pre-pressing flat roller 8 and the main pressing flat roller 16 to press the top of the plate. Simultaneously, the first cylinder 9 pushes the C-shaped frame 11 to move along the slide block 10, and the side pressing rollers 12 clamp the plate from both sides. The laser displacement sensor 17 detects the height difference between the two sides of the plate in real time and transmits the signal to the PLC. The PLC controls the corresponding second cylinder 14 to extend and retract based on the difference, driving the corresponding swing arm 15 to swing and adjust the height of the main pressing flat roller 16 until the plates are aligned. Then, the pre-welding process is triggered, completing the automated process of edge adjustment.

[0037] The specific working process of this device is as follows: 1. Loading and Traction Preparation: Place the straight-seam rectangular welded pipe to be pre-welded on the placement plate 2 above the base 1. One end of the welded pipe is fixedly connected to a self-moving trolley (welded pipe traction trolley). The trolley starts along the preset trajectory, pulling the welded pipe to slide in the pre-welding direction, ensuring that the welded pipe moves along the fixed path of pre-pressing flat roller 8 → main press flat roller 16 → welding gun, so as to facilitate subsequent continuous adjustment and welding.

[0038] 2. Clamping and Positioning of the Edge Pressing Mechanism: After receiving the start signal, the PLC controller immediately interlocks and controls the first hydraulic cylinders 9 on both sides of the bottom of the gantry 3 to operate. The output shaft of the first hydraulic cylinder 9 pushes the C-shaped frame 11 to slide inward along the lower slide block 10, causing multiple side pressure rollers 12 vertically arranged on the inner side of the C-shaped frame 11 to synchronously approach the welded pipe. After the side pressure rollers 12 are in contact with the two side walls of the welded pipe, the first hydraulic cylinder 9 maintains pressure to limit the lateral displacement of the welded pipe and ensure that the sides are always aligned during the pre-welding process.

[0039] 3. Pre-pressing and leveling with pre-pressing rollers: The pre-pressing rollers move synchronously with the edge pressing mechanism. The PLC controller controls the extension of the lifting cylinder 4 on the crossbeam of the gantry frame 3. The output shaft of the lifting cylinder 4 drives the horizontal plate 6 to slide vertically downward along the column 5 of the gantry frame 3, which in turn drives the pressure head seat 7 at the bottom of the horizontal plate 6 to move downward synchronously, so that the pre-pressing roller 8 on one side of the bottom of the pressure head seat 7 fits against the top surface of the weld seam of the welded pipe. As the trolley pulls the welded pipe, the pre-pressing roller 8 rolls passively, performing preliminary flattening on the top of the welded pipe to eliminate obvious protrusions or wrinkles on the surface, so as to facilitate subsequent edge adjustment.

[0040] 4. Laser detection of misalignment: After the welded pipe is pre-pressed by the pre-pressing roller 8, it continues to move with the trolley towards the main pressing roller 16. At this time, two laser displacement sensors 17 (corresponding one-to-one with the two main pressing rollers) symmetrically arranged at the bottom of the pressure head seat 7 are activated synchronously, with their probes pointing vertically downwards towards the edges of both sides of the welded pipe, detecting the height difference between the two sides of the welded pipe in real time. The laser displacement sensors 17 convert the detected height data into electrical signals, which are transmitted to the PLC controller in real time.

[0041] 5. Precise Adjustment of the Main Pressure Roller: After receiving the signal from the laser displacement sensor 17, the PLC controller quickly calculates the height difference between the two sides of the welded pipe. If it detects that one side of the welded pipe is higher than the other, the controller immediately interlocks and controls the corresponding side's second hydraulic cylinder 14 to operate: the output shaft of the second hydraulic cylinder 14 extends and retracts, pushing the L-shaped swing arm 15, which is hinged to it, to swing around the hinge point in the middle of the pressure head seat 7, thereby driving the main pressure roller 16 at the bottom of the vertical section of the L-shaped swing arm 15 to move up and down. The main pressure roller 16 performs targeted compaction on the higher side of the welded pipe until the laser displacement sensor 17 detects that the heights on both sides are consistent, the misalignment problem is completely eliminated, and the second hydraulic cylinder 14 stops operating and maintains pressure.

[0042] 6. Synchronous Pre-welding Operation: After precise adjustment by the main pressure roller 16, the welded pipe continues to be pulled by the trolley to the pre-welding area. Since the pre-welding equipment (such as the welding gun) is located behind the main pressure roller 16, the welding gun is immediately activated when the welded pipe reaches the pre-welding position, and pre-welding is performed along the straight seam of the welded pipe. At this time, the side of the welded pipe is clamped by the side pressure roller 12, and there is no misalignment at the top, ensuring the straightness and fit of the pre-welded seam and improving the weld quality.

[0043] 7. Continuous traction to complete the entire process: The trolley maintains a constant speed (preset speed) to traction the welded pipe. The above-mentioned processes of edge clamping → pre-pressing with pre-pressing rollers → laser detection → main pressure roller adjustment → synchronous pre-welding are carried out continuously and dynamically. Until the entire welded pipe has completely passed the adjustment mechanism and the pre-welding area, the trolley stops traction and drives the welded pipe away from the equipment. The pre-welding misalignment adjustment operation of the entire straight seam rectangular welded pipe is completed.

Claims

1. An automatic pre-welding misalignment adjustment mechanism for straight-seam rectangular welded pipe, comprising a base (1), a placement plate (2) disposed on the base (1), a gantry frame (3) disposed on the base (1) and spanning both sides of the placement plate (2), an adjustment mechanism disposed between the gantry frame (3) and the placement plate (2), and edge pressing mechanisms disposed on both sides of the bottom of the gantry frame (3), characterized in that, The adjustment mechanism includes a horizontal plate (6) connected to the output shaft of the lifting cylinder (4) of the gantry (3) and vertically sliding with the column (5) of the gantry (3), a pressure head seat (7) at the bottom of the horizontal plate (6), a first adjustment component and a second adjustment component on the pressure head seat (7), and a pre-pressing flat roller (8) rotatably located on one side of the bottom of the pressure head seat (7); the pressing mechanism is used in conjunction with the first adjustment component and the second adjustment component.

2. The misalignment adjustment mechanism as described in claim 1, characterized in that, The pressing mechanism includes a first oil cylinder (9), a slide (10), a C-shaped frame (11), and a side pressing roller (12). There are two of each of the first oil cylinder (9), slide (10), and C-shaped frame (11). Mounting plates (13) are provided on both sides of the bottom of the gantry (3). The two first oil cylinders (9) are respectively mounted on the two mounting plates (13). The two slides (10) are respectively located on both sides of the base (1) and below the mounting plates (13). The two C-shaped frames (11) are respectively connected to the output shafts of the two first oil cylinders (9) and their bottoms slide in cooperation with the slides (10). There are multiple side pressing rollers (12) that are vertically symmetrically rotated and connected to the two C-shaped frames (11).

3. The misalignment adjustment mechanism as described in claim 1, characterized in that, The first adjustment assembly and the second adjustment assembly both include a second hydraulic cylinder (14) and an L-shaped swing arm (15); the two second hydraulic cylinders (14) are symmetrically hinged to the bottom of the pressure head seat (7), and the horizontal section of the two swing arms (15) is symmetrically rotatably connected to one side of the middle of the pressure head seat (7) at one end away from its vertical section. The horizontal section of the two swing arms (15) is rotatably connected to the output shaft of the two second hydraulic cylinders (14) respectively. The bottom of the vertical section of the two swing arms (15) is rotatably connected to a main pressure roller (16).

4. The misalignment adjustment mechanism as described in claim 3, characterized in that, Two laser displacement sensors (17) are symmetrically arranged at the bottom of the pressure head seat (7), and the two laser displacement sensors (17) are arranged corresponding to the two main pressure rollers (16).

5. The misalignment adjustment mechanism as described in claim 4, characterized in that, The two laser displacement sensors (17) are interlocked with the two second hydraulic cylinders (14) respectively via a PLC controller.

6. The misalignment adjustment mechanism as described in claim 5, characterized in that, The lifting cylinder (4) and the first cylinder (9) are interlocked with the PLC controller.

Images