Reverse balanced flange connection node and manufacturing method and application thereof

Abstract

The application relates to a reverse balanced flange connecting node and a manufacturing method and application thereof, which comprises an upper flange tower drum and a lower flange tower drum, an upper flange plate and an upper stiffening plate are welded to the inner wall of the upper flange tower drum, a lower flange plate and a lower stiffening plate are welded to the inner wall of the lower flange tower drum, the upper stiffening plate and the lower stiffening plate adopt a broken line arrangement, the upper surface of the upper stiffening plate is welded to the upper flange plate, the lower surface of the lower stiffening plate is welded to the lower flange plate, bolt holes are arranged on the upper flange plate and the lower flange plate, high-strength bolts pass through the bolt holes to connect the upper flange tower drum and the lower flange tower drum. An upper balancing plate is welded to the inner side of the upper stiffening plate, a lower balancing plate is welded to the inner side of the lower stiffening plate, an upper sleeve is welded to the inner side of the upper balancing plate, and a lower sleeve is welded to the inner side of the lower balancing plate, and the upper sleeve and the lower sleeve are connected through shear-resistant bolts. Compared with the prior art, the application has the advantages of low processing difficulty, convenient installation, good torsional resistance, high ring stiffness, improved stiffening plate welding conditions and the like.

Description

Technical Field

[0001] This invention relates to the field of steel tower connection technology for wind power generation towers in structural engineering, specifically to a reverse balance flange connection node, its manufacturing method, and its application. Background Technology

[0002] As wind turbines become larger, the hub height is constantly increasing, leading to a sharp increase in the ultimate load on the steel tower cross-section. The stress performance of large-diameter steel tower connection nodes has become a critical factor in ensuring the safe and stable operation of wind turbines. Traditional forged flange connections involve thick flange plates that require milling the entire flange face, resulting in a large workload, high processing difficulty, and high cost. Furthermore, flange plates are prone to deformation under fatigue loads, causing loosening of connecting bolts and failing to meet the performance requirements for long-term service.

[0003] The reverse balancing flange, as a novel connection type, places the flange plate and stiffening plate in opposite directions inside the tower, forming a centripetally arranged balancing surface. This structure eliminates the need to thicken the flange plate; simply increasing the height of the stiffening plate significantly improves flange stiffness, offering advantages such as reduced steel consumption and lower processing difficulty. Simultaneously, the increased stiffening plate height allows for longer bolt lengths, facilitating precise application and maintenance of preload, and enhancing the anti-loosening performance of the bolt connection. However, existing reverse balancing flange connections still have certain shortcomings.

[0004] The stiffening plates in patent CN110671278A are arranged radially. Due to the small spacing between adjacent stiffening plates, the operating space is limited when welding to the tower wall, making it difficult to guarantee welding quality. Furthermore, the balance surface area on the inner side of the stiffening plates is small, which easily leads to misalignment of the mating surfaces during installation. More critically, when the flange is subjected to overload bending moment, the contact surface between the flange and the tower wall partially disengages, transforming the torsional resistance mechanism of the complete annular section under normal stress into that of an open arc section. This significantly reduces the torsional resistance at the flange, further exacerbating the risk of misalignment of the stiffening plates.

[0005] Although patent CN110671279A eliminated the balance surface on the inner side of the stiffening plate and replaced it with a balance ring, increasing the area of ​​the tightening surface and eliminating the hidden danger of misalignment of the tightening surface, the overall torsional resistance of the node is still relatively weak because the stiffening plate is still arranged radially. Summary of the Invention

[0006] Existing reverse balancing flange connections suffer from insufficient torsional resistance, difficulty in ensuring the welding quality of stiffening plates, and a tendency for misalignment of the tightening surfaces during installation. Specifically, in existing reverse balancing flange connections, stiffening plates are often arranged radially. When welding the stiffening plates to the inner wall of the tower, the small spacing between the stiffening plates results in insufficient welding space, which is detrimental to welding quality. Simultaneously, the balance surface on the inner side of the stiffening plate is small, making misalignment of the tightening surfaces easy to occur during installation. Furthermore, when the flange is subjected to overload bending moment, the contact surface between the flange and the tower wall partially disengages, transforming the torsional resistance of the complete annular section under normal stress into that of an open arc section, leading to a decrease in the torsional resistance at the flange and further exacerbating the misalignment of the stiffening plates. Therefore, this invention provides a reverse balancing flange connection with a steel tower rib plate that offers superior torsional resistance, low processing difficulty, convenient installation, excellent fatigue resistance, good torsional resistance, and high circumferential stiffness.

[0007] The objective of this invention can be achieved through the following technical solutions: One objective of this invention is to provide a reverse balancing flange connection node, comprising an upper flange tower and a lower flange tower, wherein an upper flange plate and an upper stiffening plate are welded to the inner wall of the upper flange tower, and a lower flange plate and a lower stiffening plate are welded to the inner wall of the lower flange tower, characterized in that it comprises: There are 2n upper stiffening plates, which are welded to the lower end face of the upper flange plate along the circumference of the upper flange plate. The 2n upper stiffening plates are divided into n groups. The two upper stiffening plates in each group are arranged in a figure-eight shape. The end of the two plates that are farther apart is welded to the upper flange tower, and the end that is closer together is provided with an upper balance plate that is welded to the two plates. There are 2n lower stiffening plates, which are welded to the upper surface of the lower flange plate along the circumference of the lower flange plate. The 2n lower stiffening plates are divided into n groups. The two lower stiffening plates in each group are arranged in a figure-eight shape. The end of the two plates that are farther apart is welded to the lower flange tower, and the end that is closer together is provided with a lower balance plate that is welded to the two plates. The upper flange plate and the lower flange plate are provided with multiple pairs of bolt holes. A high-strength bolt is screwed into each pair of bolt holes. The high-strength bolt passes through the bolt holes and the upper flange plate to connect the upper flange tower and the lower flange tower. An upper sleeve is welded to the upper balance plate, and a lower sleeve is welded to the lower balance plate. The upper balance plate and the upper sleeve abut against the lower balance plate and the lower sleeve, respectively. Shear bolts are screwed into the upper sleeve and the lower sleeve.

[0008] Furthermore, the lower end face of the upper flange tower, the lower end face of the upper balance plate, the lower end face of the upper sleeve, the upper end face of the lower flange tower, the upper end face of the lower balance plate, and the upper end face of the lower sleeve are all milled flat.

[0009] Furthermore, there is a gap between the upper stiffening plate and the lower stiffening plate after they are joined together.

[0010] Furthermore, the lower end face of the upper flange tower and the upper end face of the lower flange tower form a tower mating surface after contact, and the upper balance plate and the lower balance plate form a balance contact surface after contact. The lower surface of the upper stiffening plate and the upper surface of the lower stiffening plate are both set at heights that are higher or lower than the set heights of the tower docking surface and the balance contact surface.

[0011] Furthermore, the lower stiffening plate is provided with guide slopes on the side near the lower flange tower and on the side near the lower balance plate.

[0012] Furthermore, the upper and lower balance plates are steel plates of the same thickness and length, and the taper of the upper and lower flange towers is consistent with the taper of the steel tower body.

[0013] Furthermore, the upper flange tower and the lower flange tower are welded to the corresponding steel tower body to form an integral whole.

[0014] The second objective of this invention is to provide a method for manufacturing the reverse balancing flange connection node as described above, comprising the following steps: Prepare or manufacture the following components separately: upper flange tower, lower flange tower, upper flange plate, lower flange plate, upper stiffening plate, lower stiffening plate, upper balance plate, lower balance plate, upper sleeve, lower sleeve, high-strength bolts, and shear bolts. The upper flange plate is welded to the inner wall of the tower tube, and the lower flange plate is welded to the inner wall of the tower tube. Two upper stiffening plates are welded to one side of the upper balance plate, and an upper sleeve is welded to the other side; two lower stiffening plates are welded to one side of the lower balance plate, and a lower sleeve is welded to the other side. The side of the upper stiffening plate away from the upper balance plate is welded to the inner wall of the upper flange tower, and the upper surface of the upper stiffening plate is welded to the upper flange plate; the side of the lower stiffening plate away from the lower balance plate is welded to the inner wall of the lower flange tower, and the lower surface of the lower stiffening plate is welded to the lower flange plate. The lower end face of the upper flange tower, the lower end face of the upper balance plate, the lower end face of the upper sleeve, the upper end face of the lower flange tower, the upper end face of the lower balance plate, and the upper end face of the lower sleeve are all milled flat. Connect the upper flange tower to the lower flange tower, connect the upper balance plate to the lower balance plate, connect the upper sleeve to the lower sleeve, align the upper stiffening plate and the lower stiffening plate, pass the high-strength bolts through the bolt holes through the upper flange plate and the lower flange plate, tighten some of the high-strength bolts, and connect the upper flange tower and the lower flange tower. A reverse-balanced flange connection node is created by adjusting the roundness of the upper and lower flange towers using flexible tie rods equipped with turnbuckles.

[0015] The third objective of this invention is to provide an application of the reverse balancing flange connection node as described above in the connection of steel towers, preferably, the steel tower is a wind turbine steel tower.

[0016] Furthermore, the reverse balancing flange connection node is equipped with some high-strength bolts and flexible tie rods when it leaves the factory; This application method includes the following steps: Transport the reverse balance flange connection node to the tower processing plant; Remove the high-strength bolts and flexible tie rods; Weld the upper flange tower and the lower flange tower to their respective tower bodies; The roundness of the reverse balance flange connection node is adjusted by a flexible tie rod equipped with turnbuckles; Transported to the wind farm, flexible tie rods removed, and hoisted; Connect the upper flange tower to the lower flange tower, connect the upper balance plate to the lower balance plate, connect the upper sleeve to the lower sleeve, align the upper stiffening plate and the lower stiffening plate, pass the shear bolts through the upper sleeve and the lower sleeve and tighten the nuts, and pass the high-strength bolts through the bolt holes through the upper flange plate and the lower flange plate and apply preload.

[0017] Compared with the prior art, the present invention has the following advantages: (1) The present invention changes the radially arranged stiffening plate to a zigzag arrangement, cancels the inner balance surface of the stiffening plate, and replaces the balance plate contact surface. The tower, stiffening plate and balance plate form a structural system similar to a "planar truss", realizes the continuous transmission of force and improves the torsional performance of the flange connection node.

[0018] (2) The inner side of the stiffening plate of the present invention is welded with a balance plate, the balance surface of the stiffening plate is eliminated, and the contact surface of the balance plate is used as the balance surface. The distance between the balance surface and the cylinder wall is increased, the compressive stress of the contact surface of the cylinder wall is increased, and the possibility of cracks in the contact surface of the cylinder wall is reduced.

[0019] (3) The weld between the stiffening plate and the cylinder wall and the balance plate arranged in the zigzag pattern of the present invention can be welded by single-sided bevel welding, which makes it easy to ensure the quality of the weld and has low processing difficulty.

[0020] (4) The upper and lower balance plates of the present invention are welded with upper and lower sleeves on the inner side. During installation, the shear bolts pass through the upper and lower sleeves to connect. The contact surface of the balance plate and the contact surface of the sleeve are the balance surface. The balance surface is enlarged, and the shear bolts are used for auxiliary positioning to increase the compressive stress on the contact surface, eliminate the possibility of misalignment of the flange contact surface, and improve the installation accuracy. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the present invention installed on a wind turbine tower structure; Figure 2for Figure 1 A partial structural schematic diagram of the AA section; Figure 3 for Figure 2 A schematic diagram of the first structural type of BB cross-section; Figure 4 for Figure 2 A schematic diagram of the second structure of the BB cross section; The numbers in the diagram are as follows: 1 is the upper flange tower; 2 is the lower flange tower; 3 is the upper flange plate; 4 is the lower flange plate; 5 is the upper stiffening plate; 6 is the lower stiffening plate; 7 is the upper balance plate; 8 is the lower balance plate; 9 is the upper sleeve; 10 is the lower sleeve; 11 is the bolt hole; 12 is the high-strength bolt; 13 is the shear bolt; 14 is the tower butt joint surface; 15 is the balance contact surface; 16 is the tower body; 17 is the guide slope. Detailed Implementation

[0022] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. These embodiments are implemented based on the technical solution of the present invention, providing detailed implementation methods and specific operating procedures. However, the scope of protection of the present invention is not limited to the following embodiments.

[0023] Unless otherwise specified in this invention, the component model, material name, connection structure, control method, and other features are considered to be common technical features disclosed in the prior art.

[0024] In the description of this invention, it should be understood that the terms "upper", "lower", "vertical", "horizontal", "top", "bottom", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0025] In the description of this invention, "multiple" means two or more, unless otherwise explicitly specified. Furthermore, the terms "installation," "connection," and "linking" should be interpreted broadly; for example, they can refer to a fixed connection, a detachable connection, or an integrated connection; they can refer to a bolted connection or a welded connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art will understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0026] This paper addresses the problems of insufficient torsional resistance, difficulty in ensuring the welding quality of stiffening plates, and easy misalignment of the tightening surface during installation in existing reverse balancing flange connections. Specifically, in existing reverse balancing flange connections, stiffening plates are mostly arranged radially. When welding stiffening plates to the inner wall of the tower, the small spacing between the stiffening plates results in insufficient welding operation space, which is detrimental to welding quality. At the same time, the balancing surface on the inner side of the stiffening plate is small, which easily leads to misalignment of the tightening surface during installation. Furthermore, when the flange is subjected to overload bending moment, the contact surface between the flange and the tower wall partially disengages, transforming the torsional resistance of the complete annular section under normal stress into the torsional resistance of the open arc section, resulting in a decrease in the torsional resistance of the flange and further exacerbating the misalignment of the stiffening plates.

[0027] This invention provides a steel tower tube with a zigzag rib plate and an over-limit torsional reverse balance flange connection node, such as... Figure 1 As shown, the tower includes an upper flange tower 1 and a lower flange tower 2. The contact surface between the upper flange tower 1 and the lower flange tower 2 is the tower butt joint surface 14. The upper flange tower 1 and the lower flange tower 2 are welded to the corresponding tower body 16 to form a whole, and the taper of the upper flange tower 1 and the lower flange tower 2 is consistent with the taper of the tower body 16.

[0028] like Figure 2 As shown, the inner wall of the upper flange tower 1 is welded with an upper flange plate 3 and an upper stiffening plate 5, and the inner wall of the lower flange tower 2 is welded with a lower flange plate 4 and a lower stiffening plate 6. The upper stiffening plate 5 and the lower stiffening plate 6 are arranged in a zigzag pattern. The upper surface of the upper stiffening plate 5 is welded to the upper flange plate 3, and the lower surface of the lower stiffening plate 6 is welded to the lower flange plate 4. Bolt holes 11 are provided on the upper flange plate 3 and the lower flange plate 4. High-strength bolts 12 pass through the bolt holes 11 to connect the upper flange tower 1 and the lower flange tower 2.

[0029] like Figure 2 and Figure 3 As shown, an upper balancing plate 7 is welded to the inner side of the upper stiffening plate 5 on the side away from the upper flange tower 1, and a lower balancing plate 8 is welded to the lower stiffening plate 6 on the side away from the lower flange tower 2. The two upper stiffening plates 5 are welded to one upper balancing plate 7, and the two lower stiffening plates 6 are welded to one lower balancing plate 8. The contact surface between the upper balancing plate 7 and the lower balancing plate 8 is the balancing contact surface 15. The upper balancing plate 7 and the lower balancing plate 8 are steel plates of the same length and thickness.

[0030] like Figure 3 As shown, an upper sleeve 9 is welded to the inner side of the upper balance plate 7, and a lower sleeve 10 is welded to the inner side of the lower balance plate 8. The upper sleeve 9 and the lower sleeve 10 are connected by shear bolts 13.

[0031] The lower end face of the upper flange tower 1, the lower end face of the upper balance plate 7, the lower end face of the upper sleeve 9, the upper end face of the lower flange tower 2, the upper end face of the lower balance plate 8, and the upper end face of the lower sleeve 10 are all milled flat.

[0032] A gap is provided between the lower surface of the upper stiffening plate 5 and the upper surface of the lower stiffening plate 6, so that they do not directly contact each other to avoid interference during docking. Based on the relative positional relationship between the stiffening plates and the docking surfaces, the present invention provides the following two embodiments: Implementation Method 1: like Figure 2 and Figure 3 As shown, the lower end face of the upper flange tower 1 and the upper end face of the lower flange tower 2 are connected to form the tower docking surface 14, and the upper balance plate 7 and the lower balance plate 8 are connected to form the balance contact surface 15.

[0033] The lower surface of the upper stiffening plate 5 and the upper surface of the lower stiffening plate 6 are both set at a height higher than the tower docking surface 14 and the balance contact surface 15. That is, the docking gap between the upper stiffening plate 5 and the lower stiffening plate 6 is located above the docking surface and the balance contact surface.

[0034] In addition, the lower stiffening plate 6 is provided with guide slopes 17 on the side near the lower flange tower 2 and the side near the lower balance plate 8, so as to play a guiding role in the docking process, facilitate quick and accurate alignment, increase the welding operation space, improve weld accessibility, and ensure welding quality.

[0035] Implementation Method Two: like Figure 4 As shown, the lower end face of the upper flange tower 1 and the upper end face of the lower flange tower 2 are connected to form the tower docking surface 14, and the upper balance plate 7 and the lower balance plate 8 are connected to form the balance contact surface 15.

[0036] The lower surface of the upper stiffening plate 5 and the upper surface of the lower stiffening plate 6 are both set at a height lower than the set height of the tower docking surface 14 and the balance contact surface 15. That is, the docking gap between the upper stiffening plate 5 and the lower stiffening plate 6 is located below the docking surface and the balance contact surface.

[0037] Accordingly, the upper stiffening plate 5 is provided with guide slopes 17 on the side near the upper flange tower 1 and the side near the upper balance plate 7 to provide guidance during the butt joint and welding process and improve the welding operation space of the structure on this side.

[0038] This invention also provides a method for manufacturing a steel tower tube with a zigzag rib plate that exceeds the limit of torsional resistance and reverse balance flange connection, comprising the following steps: a. Fabricate the following components according to the design requirements: upper flange tower 1, lower flange tower 2, upper flange plate 3, lower flange plate 4, upper stiffening plate 5, lower stiffening plate 6, upper balance plate 7, lower balance plate 8, upper sleeve 9, lower sleeve 10, high-strength bolt 12, and shear bolt 13. b. Weld upper flange plate 3 to the inner wall of upper flange tower 1, and weld lower flange plate 4 to the inner wall of lower flange tower 2; c. Two upper stiffening plates 5 are welded to one side of the upper balance plate 7, and an upper sleeve 9 is welded to the other side; two lower stiffening plates 6 are welded to one side of the lower balance plate 8, and a lower sleeve 10 is welded to the other side. d. The side of the upper stiffening plate 5 away from the upper balance plate 7 is welded to the inner wall of the upper flange tower 1, and the upper surface of the upper stiffening plate 5 is welded to the upper flange plate 3; the side of the lower stiffening plate 6 away from the lower balance plate 8 is welded to the inner wall of the lower flange tower 2, and the lower surface of the lower stiffening plate 6 is welded to the lower flange plate 4. e. The lower end face of the upper flange tower 1, the lower end face of the upper balance plate 7, the lower end face of the upper sleeve 9, the upper end face of the lower flange tower 2, the upper end face of the lower balance plate 8, and the upper end face of the lower sleeve 10 are all milled flat. f. Connect the upper flange tower 1 with the lower flange tower 2, connect the upper balance plate 7 with the lower balance plate 8, connect the upper sleeve 9 with the lower sleeve 10, align the upper stiffening plate 5 with the lower stiffening plate 6, and pass the high-strength bolts 12 through the bolt holes 11 through the upper flange plate 3 and the lower flange plate 4. Tighten some of the high-strength bolts 12 to connect the upper flange tower 1 and the lower flange tower 2. g. Install 3 flexible tie rods with turnbuckles on them and adjust the flange roundness.

[0039] Furthermore, the above-mentioned steel tower tube folded rib plate over-limit anti-torsion reverse balance flange connection node is applied to the processing and hoisting installation of steel tower tubes. The reverse balance flange connection node is equipped with some high-strength bolts 12 and flexible tie rods when it leaves the factory. This application method includes the following steps: a. Transport the above-mentioned steel tower tube folded rib plate over-limit anti-torsion reverse balance flange connection node to the tower tube processing plant. b. Remove high-strength bolt 12 and flexible tie rod; c. Weld the upper flange tower 1 and the lower flange tower 2 to the corresponding tower body 16 respectively; d. Reinstall the three tie rods and adjust the flange roundness.

[0040] e. Transport to the wind farm, remove the flexible tie rods, and hoist the equipment; f. Connect the upper flange tower 1 with the lower flange tower 2, connect the upper balance plate 7 with the lower balance plate 8, connect the upper sleeve 9 with the lower sleeve 10, align the upper stiffening plate 5 with the lower stiffening plate 6, pass the shear bolt 13 through the upper sleeve 9 and the lower sleeve 10 and tighten the nut, and pass the high-strength bolt 12 through the bolt hole 11 through the upper flange plate 3 and the lower flange plate 4 and apply preload.

[0041] Example 1 like Figure 1-3As shown, this embodiment provides a steel tower tube with a zigzag rib plate for over-limit torsional resistance and reverse balance flange connection, including an upper flange tower tube 1 and a lower flange tower tube 2. The upper flange tower tube 1 and the lower flange tower tube 2 are welded to the corresponding tower tube body 16 to form an integral whole, and the taper of the upper flange tower tube 1 and the lower flange tower tube 2 is consistent with the taper of the steel tower tube body 16 to ensure the structural continuity and smooth force transmission between the connection node and the tower body.

[0042] In this embodiment, the upper flange tower 1 and the lower flange tower 2 are connected through the tower docking surface 14 between them, forming a continuous structure of the entire tower.

[0043] In this embodiment, the inner wall of the upper flange tower 1 is welded with an upper flange plate 3 and an upper stiffening plate 5, and the inner wall of the lower flange tower 2 is welded with a lower flange plate 4 and a lower stiffening plate 6. The upper flange plate 3 and the lower flange plate 4 are provided with a plurality of bolt holes 11, and high-strength bolts 12 are used to fasten the upper flange tower 1 and the lower flange tower 2 together through the bolt holes 11, forming the main force transmission path of the flange connection.

[0044] like Figure 2 As shown, in this embodiment, both the upper stiffening plate 5 and the lower stiffening plate 6 are arranged in a zigzag pattern. Specifically, there are 2n upper stiffening plates 5, where n is a positive integer, which are evenly distributed along the circumference of the upper flange plate 3 and welded to the lower end face of the upper flange plate 3; similarly, there are 2n lower stiffening plates 6, which are evenly distributed along the circumference of the lower flange plate 4 and welded to the upper end face of the lower flange plate 4.

[0045] The 2n upper stiffening plates 5 are divided into n groups, and the two upper stiffening plates 5 in each group are arranged in a figure-eight shape. In each group, the ends of the two upper stiffening plates 5 that are farther apart are welded to the inner wall of the upper flange tower 1, while the ends that are closer together are welded to an upper balance plate 7.

[0046] Correspondingly, the 2n lower stiffening plates 6 are also divided into n groups. The two lower stiffening plates 6 in each group are arranged in a figure-eight shape. The ends of the two plates that are farther apart are welded to the inner wall of the lower flange tower 2, and the ends that are closer together are welded to a lower balance plate 8.

[0047] Through this figure-eight zigzag rib arrangement, the upper flange tower 1, upper stiffening plate 5 and upper balance plate 7, as well as the lower flange tower 2, lower stiffening plate 6 and lower balance plate 8, each form a structural system similar to a planar truss, realizing the continuous transfer of loads and significantly improving the torsional performance of the flange connection nodes.

[0048] In this embodiment, the upper balancing plate 7 and the lower balancing plate 8 are made of steel plates of the same length and thickness. An upper sleeve 9 is welded to the inner side of the upper balancing plate 7, and a lower sleeve 10 is welded to the inner side of the lower balancing plate 8. The upper balancing plate 7 and the lower balancing plate 8 form a balancing contact surface 15 after being joined. The upper sleeve 9 and the lower sleeve 10 abut against each other and are connected by screwing in shear bolts 13. The balancing contact surface 15 increases the contact bearing area of ​​the flange joint; simultaneously, the cooperation between the sleeve and the shear bolts 13 not only assists in positioning and improves installation accuracy, but also increases the compressive stress on the contact surface, effectively eliminating the possibility of misalignment of the flange contact surface.

[0049] The lower end face of the upper flange tower 1, the lower end face of the upper balance plate 7, the lower end face of the upper sleeve 9, the upper end face of the lower flange tower 2, the upper end face of the lower balance plate 8, and the upper end face of the lower sleeve 10 are all milled flat to ensure tight contact and uniform force transmission after docking.

[0050] A gap is provided between the lower surface of the upper stiffening plate 5 and the upper surface of the lower stiffening plate 6, so that the two do not come into direct contact and thus avoid interference during docking.

[0051] like Figure 3 As shown, in this embodiment, the lower end face of the upper flange tower 1 and the upper end face of the lower flange tower 2 are joined to form a tower docking surface 14, and the upper balance plate 7 and the lower balance plate 8 are joined to form a balance contact surface 15. The lower surface of the upper stiffening plate 5 and the upper surface of the lower stiffening plate 6 are both set at heights higher than the tower docking surface 14 and the balance contact surface 15, that is, the docking gap between the upper stiffening plate 5 and the lower stiffening plate 6 is located above the docking surface and the balance contact surface.

[0052] In addition, the lower stiffening plate 6 is provided with guide slopes 17 on the side near the lower flange tower 2 and the side near the lower balance plate 8, so as to play a guiding role in the docking process, facilitate quick and accurate alignment, increase the welding operation space, improve weld accessibility, and ensure welding quality.

[0053] This embodiment also provides a method for manufacturing a steel tower tube with a broken rib plate that exceeds the limit of torsional resistance and reverse balance flange connection node. The above-mentioned steel tower tube with a broken rib plate that exceeds the limit of torsional resistance and reverse balance flange connection node can be manufactured through the following steps: (a) Fabricate or prepare each component according to the design requirements, including upper flange tower 1, lower flange tower 2, upper flange plate 3, lower flange plate 4, upper stiffening plate 5, lower stiffening plate 6, upper balance plate 7, lower balance plate 8, upper sleeve 9, lower sleeve 10, high-strength bolt 12 and shear bolt 13. (b) Weld the upper flange plate 3 to the inner wall of the upper flange tower 1, and weld the lower flange plate 4 to the inner wall of the lower flange tower 2; (c) Weld two upper stiffening plates 5 to one side of the upper balance plate 7 and weld the upper sleeve 9 to the other side; weld two lower stiffening plates 6 to one side of the lower balance plate 8 and weld the lower sleeve 10 to the other side. (d) Weld the side of the upper stiffening plate 5 away from the upper balance plate 7 to the inner wall of the upper flange tower 1, and weld the upper surface of the upper stiffening plate 5 to the upper flange plate 3; weld the side of the lower stiffening plate 6 away from the lower balance plate 8 to the inner wall of the lower flange tower 2, and weld the lower surface of the lower stiffening plate 6 to the lower flange plate 4. (e) The lower end face of the upper flange tower 1, the lower end face of the upper balance plate 7, the lower end face of the upper sleeve 9, the upper end face of the lower flange tower 2, the upper end face of the lower balance plate 8 and the upper end face of the lower sleeve 10 are milled flat. (f) Connect the upper flange tower 1 and the lower flange tower 2, connect the upper balance plate 7 and the lower balance plate 8, and connect the upper sleeve 9 and the lower sleeve 10 to align the upper stiffening plate 5 and the lower stiffening plate 6. Insert the high-strength bolts 12 through the bolt holes 11 through the upper flange plate 3 and the lower flange plate 4, and tighten some of the high-strength bolts 12 to complete the pre-connection of the upper flange tower 1 and the lower flange tower 2. (g) Install three flexible tie rods with turnbuckles, and adjust the turnbuckles to correct and maintain the roundness of the upper flange tower 1 and the lower flange tower 2 to obtain the reverse balance flange connection node.

[0054] In step (f), tightening some of the high-strength bolts 12 means that: the reverse balance flange connection node is made in the flange processing plant and connected with some high-strength bolts before leaving the factory. At this time, the upper flange tower 1 and the lower flange tower 2 on the flange node have not yet been welded to the tower body 16. After the flange processing plant finishes making it, it is transported to the tower processing plant. The paired flange nodes are first disassembled, that is, the high-strength bolts 12 and flexible tie rods are removed, and then they are welded to the tower body respectively. Then, it is transported to the wind farm in sections and then hoisted. During the hoisting and installation at the wind farm, all the high-strength bolts 12 are installed and tightened. That is to say, when the flange is finished and leaves the factory, it is in pairs and has some high-strength bolts 12 installed, which are only for fixing. At the tower processing plant, the high-strength bolts 12 are removed. When the tower is hoisted, the high-strength bolts 12 are not installed. After hoisting into place, all the high-strength bolts 12 are installed during installation.

[0055] This embodiment also provides an application method for the reverse balance flange connection node of the steel tower's zigzag rib plate exceeding the limit of torsional resistance. The above-mentioned reverse balance flange connection node can be applied in the connection of wind turbine steel towers as follows: The reverse balancing flange connection node is pre-installed with some high-strength bolts (12) and flexible tie rods. The application method includes the following steps: (a) Transport the reverse balance flange connection node to the tower processing plant; (b) Remove high-strength bolt 12 and flexible tie rod; (c) Weld the upper flange tower 1 and the lower flange tower 2 to the corresponding tower body 16 to form a whole; (d) Reinstall three flexible tie rods with turnbuckles, and adjust the roundness of the reverse balance flange connection node by adjusting the turnbuckles to ensure that the flatness of the flange end face meets the design requirements; (e) Transport the connecting nodes to the wind farm, remove the flexible tie rods, and carry out hoisting operations; (f) During on-site installation, connect the upper flange tower 1 with the lower flange tower 2, the upper balance plate 7 with the lower balance plate 8, and the upper sleeve 9 with the lower sleeve 10 to align the upper stiffening plate 5 with the lower stiffening plate 6; pass the shear bolts 13 through the upper sleeve 9 and the lower sleeve 10 and tighten the nuts to achieve shear connection and precise positioning between the balance plates; then pass the high-strength bolts 12 through the bolt holes 11 through the upper flange plate 3 and the lower flange plate 4, and apply pre-tension according to the design requirements to complete the final installation of the entire flange connection node.

[0056] Through the above structural arrangement and construction process, this invention improves the traditional centripetal stiffening plate arrangement into a zigzag arrangement, and uses the contact surface of the balance plate to replace the inner balance surface of the stiffening plate, so that the tower, stiffening plate and balance plate form a structural system similar to a planar truss, realizing the continuous transmission of internal forces and significantly improving the torsional bearing capacity of the connection node; the increased distance between the balance surface and the cylinder wall effectively increases the compressive stress on the contact surface and reduces the possibility of cracks on the cylinder wall contact surface; the zigzag arrangement allows for single-sided bevel welding of the weld, which makes it easy to ensure welding quality and reduces processing difficulty; at the same time, the contact surface of the balance plate and the contact surface of the sleeve together form a balanced bearing surface, which, together with the auxiliary positioning effect of the shear bolts, not only increases the compressive stress on the contact surface, but also effectively eliminates the possibility of misalignment of the flange contact surface, comprehensively improving the structural reliability and installation accuracy of the flange connection node.

[0057] Example 2 like Figure 1-2 , Figure 4 As shown, this embodiment provides a steel tower tube with a zigzag rib plate for over-limit torsional resistance and reverse balance flange connection, including an upper flange tower tube 1 and a lower flange tower tube 2. The upper flange tower tube 1 and the lower flange tower tube 2 are welded to the corresponding tower tube body 16 to form an integral whole, and the taper of the upper flange tower tube 1 and the lower flange tower tube 2 is consistent with the taper of the steel tower tube body 16 to ensure the structural continuity and smooth force transmission between the connection node and the tower body.

[0058] In this embodiment, the upper flange tower 1 and the lower flange tower 2 are connected through the tower docking surface 14 between them, forming a continuous structure of the entire tower.

[0059] In this embodiment, the inner wall of the upper flange tower 1 is welded with an upper flange plate 3 and an upper stiffening plate 5, and the inner wall of the lower flange tower 2 is welded with a lower flange plate 4 and a lower stiffening plate 6. The upper flange plate 3 and the lower flange plate 4 are provided with a plurality of bolt holes 11, and high-strength bolts 12 are used to fasten the upper flange tower 1 and the lower flange tower 2 together through the bolt holes 11, forming the main force transmission path of the flange connection.

[0060] like Figure 2 As shown, in this embodiment, both the upper stiffening plate 5 and the lower stiffening plate 6 are arranged in a zigzag pattern. Specifically, there are 2n upper stiffening plates 5, where n is a positive integer, which are evenly distributed along the circumference of the upper flange plate 3 and welded to the lower end face of the upper flange plate 3; similarly, there are 2n lower stiffening plates 6, which are evenly distributed along the circumference of the lower flange plate 4 and welded to the upper end face of the lower flange plate 4.

[0061] The 2n upper stiffening plates 5 are divided into n groups, with two upper stiffening plates 5 arranged in a V-shape in each group. In each group, the ends of the two upper stiffening plates 5 that are farther apart are welded to the inner wall of the upper flange tower 1, while the ends that are closer together are welded to a single upper balancing plate 7. Correspondingly, the 2n lower stiffening plates 6 are also divided into n groups, with two lower stiffening plates 6 arranged in a V-shape in each group. The ends of the two lower stiffening plates that are farther apart are welded to the inner wall of the lower flange tower 2, while the ends that are closer together are welded to a single lower balancing plate 8. Through this V-shaped zigzag rib arrangement, a planar truss-like structural system is formed between the upper flange tower 1, the upper stiffening plates 5, and the upper balancing plate 7, and between the lower flange tower 2, the lower stiffening plates 6, and the lower balancing plate 8, respectively. This achieves continuous load transfer and significantly improves the torsional resistance of the flange connection nodes.

[0062] In this embodiment, the upper balancing plate 7 and the lower balancing plate 8 are made of steel plates of the same length and thickness. An upper sleeve 9 is welded to the inner side of the upper balancing plate 7, and a lower sleeve 10 is welded to the inner side of the lower balancing plate 8. The upper balancing plate 7 and the lower balancing plate 8 form a balancing contact surface 15 after being joined. The upper sleeve 9 and the lower sleeve 10 abut against each other and are connected by screwing in shear bolts 13. The balancing contact surface 15 increases the contact bearing area of ​​the flange joint; simultaneously, the cooperation between the sleeve and the shear bolts 13 not only assists in positioning and improves installation accuracy, but also increases the compressive stress on the contact surface, effectively eliminating the possibility of misalignment of the flange contact surface.

[0063] The lower end face of the upper flange tower 1, the lower end face of the upper balance plate 7, the lower end face of the upper sleeve 9, the upper end face of the lower flange tower 2, the upper end face of the lower balance plate 8, and the upper end face of the lower sleeve 10 are all milled flat to ensure tight contact and uniform force transmission after docking.

[0064] A gap is provided between the lower surface of the upper stiffening plate 5 and the upper surface of the lower stiffening plate 6, so that the two do not come into direct contact and thus avoid interference during docking.

[0065] like Figure 4 As shown, in this embodiment, the lower end face of the upper flange tower 1 and the upper end face of the lower flange tower 2 form a tower docking surface 14 after contact, and the upper balance plate 7 and the lower balance plate 8 form a balance contact surface 15 after contact. Unlike embodiment 1, the lower surface of the upper stiffening plate 5 and the upper surface of the lower stiffening plate 6 are both set at heights lower than the tower docking surface 14 and the balance contact surface 15; that is, the docking gap between the upper stiffening plate 5 and the lower stiffening plate 6 is located below the docking surface and the balance contact surface.

[0066] Accordingly, in this embodiment, the upper stiffening plate 5 is provided with a guide slope 17 on the side near the upper flange tower 1 and the side near the upper balance plate 7, so as to provide guidance during the butt joint and welding process and improve the welding operation space of the structure on this side.

[0067] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention in any other way. Any person skilled in the art may make changes or modifications to the above-disclosed technical content to create equivalent embodiments. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A reverse balancing flange connection node, comprising an upper flange tower (1) and a lower flange tower (2), wherein an upper flange plate (3) and an upper stiffening plate (5) are welded to the inner wall of the upper flange tower (1), and a lower flange plate (4) and a lower stiffening plate (6) are welded to the inner wall of the lower flange tower (2), characterized in that, include: There are 2n upper stiffening plates (5) and they are welded to the lower end face of the upper flange plate (3) along the circumference of the upper flange plate (3). The 2n upper stiffening plates (5) are divided into n groups. The two upper stiffening plates (5) in each group are arranged in a figure-eight shape. The ends of the two plates that are farther apart are welded to the upper flange tower (1), and the ends that are closer together are provided with an upper balance plate (7) that is welded to the two plates. There are 2n lower stiffening plates (6) and they are welded to the upper end face of the lower flange plate (4) along the circumference of the lower flange plate (4). The 2n lower stiffening plates (6) are divided into n groups. The two lower stiffening plates (6) in each group are arranged in a figure-eight shape. The ends of the two plates that are farther apart are welded to the lower flange tower (2), and the ends that are closer together are provided with a lower balance plate (8) that is welded to the two plates. The upper flange plate (3) and the lower flange plate (4) are provided with multiple pairs of bolt holes (11), and a high-strength bolt (12) is screwed into each pair of bolt holes (11). An upper sleeve (9) is welded onto the upper balance plate (7), and a lower sleeve (10) is welded onto the lower balance plate (8). The upper balance plate (7) and the upper sleeve (9) abut against the lower balance plate (8) and the lower sleeve (10) respectively. Shear bolts (13) are screwed into the upper sleeve (9) and the lower sleeve (10).

2. The reverse balancing flange connection node according to claim 1, characterized in that, The lower end face of the upper flange tower (1), the lower end face of the upper balance plate (7), the lower end face of the upper sleeve (9), the upper end face of the lower flange tower (2), the upper end face of the lower balance plate (8), and the upper end face of the lower sleeve (10) are all milled flat.

3. A reverse balancing flange connection node according to claim 1, characterized in that, There is a gap between the upper stiffening plate (5) and the lower stiffening plate (6) after they are joined together.

4. A reverse balancing flange connection node according to claim 1, characterized in that, The lower end face of the upper flange tower (1) and the upper end face of the lower flange tower (2) are connected to form a tower docking surface (14), and the upper balance plate (7) and the lower balance plate (8) are connected to form a balance contact surface (15). The lower surface of the upper stiffening plate (5) and the upper surface of the lower stiffening plate (6) are both set at heights that are higher or lower than the set heights of the tower docking surface (14) and the balance contact surface (15).

5. A reverse balancing flange connection node according to claim 1, characterized in that, The lower stiffening plate (6) is provided with guide slopes (17) on the side near the lower flange tower (2) and on the side near the lower balance plate (8).

6. A reverse balancing flange connection node according to claim 1, characterized in that, The upper balancing plate (7) and the lower balancing plate (8) are steel plates of the same thickness and length, and the taper of the upper flange tower (1) and the lower flange tower (2) is consistent with the taper of the steel tower body.

7. A reverse balancing flange connection node according to claim 1, characterized in that, The upper flange tower (1) and the lower flange tower (2) are respectively welded to the corresponding steel tower body to form an integral whole.

8. A method for manufacturing a reverse balancing flange connection node as described in claim 1, characterized in that, Includes the following steps: (a) Prepare or manufacture the following components respectively: upper flange tower (1), lower flange tower (2), upper flange plate (3), lower flange plate (4), upper stiffening plate (5), lower stiffening plate (6), upper balance plate (7), lower balance plate (8), upper sleeve (9), lower sleeve (10), high-strength bolt (12), and shear bolt (13); (b) The upper flange plate (3) is welded to the inner wall of the upper flange tower (1), and the lower flange plate (4) is welded to the inner wall of the lower flange tower (2). (c) Two upper stiffening plates (5) are welded to one side of the upper balance plate (7), and an upper sleeve (9) is welded to the other side; two lower stiffening plates (6) are welded to one side of the lower balance plate (8), and a lower sleeve (10) is welded to the other side. (d) The side of the upper stiffening plate (5) away from the upper balance plate (7) is welded to the inner wall of the upper flange tower (1), and the upper surface of the upper stiffening plate (5) is welded to the upper flange plate (3); the side of the lower stiffening plate (6) away from the lower balance plate (8) is welded to the inner wall of the lower flange tower (2), and the lower surface of the lower stiffening plate (6) is welded to the lower flange plate (4); (e) The lower end face of the upper flange tower (1), the lower end face of the upper balance plate (7), the lower end face of the upper sleeve (9), the upper end face of the lower flange tower (2), the upper end face of the lower balance plate (8) and the upper end face of the lower sleeve (10) are all milled flat. (f) Connect the upper flange tower (1) and the lower flange tower (2), connect the upper balance plate (7) and the lower balance plate (8), connect the upper sleeve (9) and the lower sleeve (10), align the upper stiffening plate (5) and the lower stiffening plate (6), pass the high-strength bolts (12) through the bolt holes (11) through the upper flange plate (3) and the lower flange plate (4), tighten some of the high-strength bolts (12), and connect the upper flange tower (1) and the lower flange tower (2); (g) By using a flexible tie rod with turnbuckles to adjust the roundness of the upper flange tower (1) and the lower flange tower (2), a reverse balance flange connection node is obtained.

9. An application of the reverse balancing flange connection node as described in claim 1 in steel tower connection, characterized in that, The steel tower is a wind turbine steel tower.

10. The application according to claim 9, characterized in that, The reverse balance flange connection node is equipped with some high-strength bolts (12) and flexible tie rods when it leaves the factory; This application method includes the following steps: (a) Transport the reverse balance flange connection node to the tower processing plant; (b) Remove the high-strength bolts (12) and the flexible tie rod; (c) Weld the upper flange tower (1) and the lower flange tower (2) to the corresponding tower body (16) respectively; (d) Adjust the roundness of the reverse balance flange connection node by means of a flexible tie rod with turnbuckles; (e) Transport to the wind farm, remove the flexible tie rods, and hoist the equipment; (f) Connect the upper flange tower (1) and the lower flange tower (2), connect the upper balance plate (7) and the lower balance plate (8), connect the upper sleeve (9) and the lower sleeve (10), align the upper stiffening plate (5) and the lower stiffening plate (6), pass the shear bolt (13) through the upper sleeve (9) and the lower sleeve (10) and tighten the nut, pass the high-strength bolt (12) through the bolt hole (11) through the upper flange plate (3) and the lower flange plate (4) and apply preload.

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