A pile sealing structure after pile sinking for offshore wind turbine steel pipe pile and a construction method thereof

Abstract

The application discloses a pile sealing structure for offshore wind turbine steel pipe pile after pile sinking and a construction method thereof, and comprises a sealing body, an extension part, a supporting block, an external threaded part and a butt joint structure. The sealing body abuts against the inner hole end of the steel pipe pile and is sealed by a first sealing ring. The external threaded part is threadedly matched with the extension part, and the supporting block is radially locked by wedge-shaped transmission of an annular taper surface and an inclined surface of the supporting block. The butt joint structure is matched with an avoiding hole to realize external driving adaptation. The structure solves the problem that the prior art cannot simultaneously consider operation convenience, sealing reliability, adaptability and operation and maintenance convenience in offshore large-diameter steel pipe pile sealing, realizes the effects of stable locking, reliable sealing, efficient operation and convenient operation and maintenance, and is suitable for offshore harsh operation environment.

Description

Technical Field

[0001] This invention relates to the field of offshore wind turbine foundation engineering technology, specifically to a post-pile sealing structure for offshore wind turbine steel pipe piles, and also to a construction method for the post-pile sealing structure for offshore wind turbine steel pipe piles. Background Technology

[0002] In offshore wind turbine construction projects, steel pipe piles serve as the core load-bearing components of the wind turbine foundation. After pile driving, the inner holes at their ends must be sealed to prevent corrosion caused by marine salt spray, water vapor, and debris from entering the pile body, while also ensuring the safety and stability of subsequent foundation construction. The adaptability, sealing reliability, and ease of operation of the sealing structure directly affect the construction efficiency and long-term service life of the offshore wind turbine foundation.

[0003] In existing technologies, post-pile sealing solutions for offshore wind turbine steel pipe piles mainly include integral cover plate welding sealing, bolt-fastened cover plate sealing, and simple wedge block locking sealing. The integral cover plate welding sealing solution achieves sealing by welding a steel cover plate to the end of the steel pipe pile; its core feature is reliance on welding technology for sealing and fixation. The bolt-fastened cover plate sealing solution uses multiple circumferentially distributed bolts to press a cover plate with a sealing ring against the end face of the steel pipe pile; its core feature is reliance on the axial clamping force of the bolts for sealing. The simple wedge block locking sealing solution uses wedge blocks placed on the inner side of the cover plate; by striking the wedge blocks, they expand radially and press against the inner wall of the steel pipe pile to achieve locking; its core feature is reliance on the mechanical expansion force of the wedge blocks for fixation.

[0004] The existing sealing solutions mentioned above have several shortcomings in practical offshore operations: First, they lack operational convenience. Overall welding sealing requires on-site welding, which is hampered by high winds, waves, and humidity at sea, making it difficult to guarantee welding quality and resulting in low operational efficiency. Bolted sealing requires tightening each circumferential bolt individually; for large-diameter steel pipe piles (several meters in diameter), the large number of bolts makes the operation time-consuming and labor-intensive. Second, their sealing reliability is limited. Welded sealing is prone to failure due to porosity and cracks in the weld. Bolted sealing is susceptible to leakage in environments with uneven bolt stress and inconsistent sealing ring compression, especially under salt spray and wave impact. Simple wedge-shaped sealing lacks a dedicated sealing structure and relies solely on mechanical compression for initial sealing, which is insufficient for long-term sealing. Third, the adaptability and convenience of later operation and maintenance are poor. Welded sealing is a permanent sealing. When it is necessary to enter the steel pipe pile for maintenance, the cover plate needs to be cut and re-welded after maintenance. The cost is high and it is easy to damage the steel pipe pile body. Although bolt-fastened and wedge-block sealing can be disassembled, for large-diameter steel pipe piles, disassembly and reinstallation also rely on large equipment and are difficult to adapt to the locking requirements of steel pipe piles with different wall thicknesses. Fourth, the locking stability is insufficient. The radial expansion force of simple wedge-block sealing is difficult to control accurately. The locking is prone to loosening due to insufficient expansion force or damage to the inner wall of the steel pipe pile due to excessive expansion force. Bolt-fastened sealing is prone to loosening of bolts due to marine vibration, affecting the locking reliability.

[0005] In summary, the core problem with existing sealing technologies in dealing with the sealing of large-diameter offshore wind turbine steel pipe piles after pile driving is that they cannot balance ease of operation, sealing reliability, adaptability, and ease of subsequent operation and maintenance, resulting in low construction efficiency, high long-term service risk, and high operation and maintenance costs. Summary of the Invention

[0006] The purpose of this invention is to provide a post-pile sealing structure and its construction method for offshore wind turbine steel pipe piles, so as to solve the technical problem that the existing technology is difficult to balance operation convenience, sealing reliability, adaptability and post-maintenance convenience in the post-pile sealing scenario of large-diameter offshore wind turbine steel pipe piles.

[0007] To solve the above-mentioned technical problems, the present invention specifically provides the following technical solution:

[0008] This invention provides a post-pile sealing structure for offshore wind turbine steel pipe piles, comprising: a sealing body for abutting the inner bore port of the steel pipe pile; a first sealing ring provided on the sealing body, the sealing body being able to press the first sealing ring tightly against the end face of the inner bore port of the steel pipe pile, and the first sealing ring sealing the gap between the upper edge of the inner bore of the steel pipe pile and the sealing body; an extension portion fixedly connected to the sealing body and capable of extending into the inner bore of the steel pipe pile when the sealing body is in operation, the extension portion having a cavity inside, the inner wall of the cavity having an internal threaded hole; a support block slidably disposed on the cavity wall of the extension portion along the radial direction of the steel pipe pile, the support block having a first end capable of abutting against the inner wall of the steel pipe pile and a second end extending into the cavity of the extension portion, the second end having an inclined surface; at least one support block, when there is only one support block, The reaction force generated by the support block abutting against the inner wall of the steel pipe pile can push the other side of the extended part to press against the inner wall of the steel pipe pile; when there are two or more support blocks, each support block is evenly distributed around the axis of the steel pipe pile; the external threaded part has threads on its outer circumference and is threadedly engaged with the internal threaded hole, and the axis of the external threaded part is collinear with the axis of the steel pipe pile; the bottom end of the external threaded part is provided with an annular conical surface, which can cooperate with the inclined surface of the support block to drive the support block to extend radially and abut against the inner wall of the steel pipe pile when the external threaded part moves axially relative to the internal threaded hole; the butt joint structure is fixedly installed on the top of the external threaded part and can drive the external threaded part to rotate around its own axis; the sealing body is provided with a clearance hole that allows the external driving part to dock with the butt joint structure, and the projection of the clearance hole along the axis of the external threaded part covers the movement range of the butt joint structure.

[0009] According to one embodiment of the present invention, a flange structure extends radially from the top outer periphery of the external threaded component, and the bottom surface of the flange structure is higher than the upper end surface of the sealing body; a second sealing ring is provided between the bottom surface of the flange structure and the upper end surface of the sealing body, and the second sealing ring is used to seal the gap between the flange structure and the sealing body.

[0010] According to one embodiment of the present invention, the mating structure is a structure that protrudes from or is recessed into the top region of the external threaded component; the mating structure is a single structure coaxially disposed on the top of the external threaded component, and its cross-section is a polygonal or irregular structure; or the mating structure has at least two mating points, and at least one of the mating points is eccentrically disposed relative to the axis of the external threaded component; or the mating structure is a rod-shaped, block-shaped, or irregular handle structure that protrudes from the top region of the external threaded component.

[0011] According to one embodiment of the present invention, the cavity wall of the inserted part is provided with a through hole along the radial direction of the steel pipe pile, the support block is inserted into the through hole, and the support block and the through hole are slidably engaged by a slide rail.

[0012] According to one embodiment of the present invention, at the first end of the support block that contacts the inner wall of the steel pipe pile, arc-shaped anti-slip grooves are provided at intervals along the axial direction of the steel pipe pile.

[0013] According to one embodiment of the present invention, an annular groove is coaxially formed at the lower end of the sealing body along its axial direction, and a third sealing ring capable of extending axially along the sealing body is disposed in the annular groove; a first top ring capable of moving along the axis of the sealing body is disposed between the bottom of the annular groove and the third sealing ring, and a guide post extending axially from the upper end of the first top ring through the sealing body, wherein there are at least two guide posts, and each guide post is evenly distributed around the axis of the first top ring; the flange structure can press the top end of the guide post to push the first top ring when the external threaded part moves axially, thereby abutting the third sealing ring against the end face of the steel pipe pile.

[0014] According to one embodiment of the present invention, a second top ring is coaxially disposed above the sealing body, the bottom of the second top ring is fixedly connected to the top of all the guide posts, and the flange structure can abut against the upper end of the second top ring to push all the guide posts to move synchronously downward along the axial direction.

[0015] According to one embodiment of the present invention, the flange structure is provided with a ring array of balls at the contact point with the second top ring to convert sliding friction into rolling friction; or it is rotatably provided with a rotating collar that abuts against the top of the second top ring.

[0016] According to one embodiment of the present invention, the external threaded component is a hollow structure with openings at both ends; the center of the annular conical surface has a through hole, which connects the internal space of the external threaded component and the inner hole of the steel pipe pile.

[0017] This invention also provides a construction method for a post-pile driving sealing structure for offshore wind turbine steel pipe piles, used in the aforementioned post-pile driving sealing structure for offshore wind turbine steel pipe piles, comprising the following steps: S1, pre-assembling the external threaded component and the extension portion, so that the support block is in a retracted state, forming a plug-in unit; S2, hoisting and plugging the plug-in unit into the inner hole port of the completed steel pipe pile, so that the sealing body initially fits against the end face of the inner hole port of the steel pipe pile; S3, applying a clamping force towards the steel pipe pile to the sealing body, so that the first sealing ring is pre-compressed to achieve initial end face sealing; S4, connecting the external driving component and the external threaded component through the docking structure, driving the external threaded component to rotate around its own axis, so that the external threaded component relative to the extension portion... The internal threaded hole of the insertion part moves axially downward; S5, the annular conical surface at the bottom of the external threaded part moves downward and presses the inclined surface of the support block, pushing the support block to extend radially out of the insertion part along the steel pipe pile until the support block abuts against the inner wall of the steel pipe pile; when there is one support block, the support block abuts against the reaction force to push the other side of the insertion part against the inner wall of the steel pipe pile; when there are two or more support blocks, each support block is evenly stressed against the inner wall of the steel pipe pile, and the axial locking of the sealing body is achieved by means of the extrusion force and friction, thus completing the sealing operation; S6, during disassembly, the external threaded part is driven to rotate in the opposite direction through the docking structure, so that the external threaded part moves axially upward, the annular conical surface disengages from the inclined surface of the support block, the support block retracts radially and disengages from the inner wall of the steel pipe pile, and after the locking is released, the plug-in unit can be hoisted and taken out.

[0018] Compared with the prior art, the present invention has the following advantages:

[0019] The sealing body and the first sealing ring work together to achieve a reliable end face seal, improving the problem of insufficient sealing reliability in existing technologies; the wedge-shaped transmission of the external threaded part and the support block is adapted to single / multiple support block locking to achieve stable radial locking, improving the problems of uneven locking, poor adaptability and insufficient stability; the docking structure and the clearance hole are adapted to external drive, improving the convenience of operation and improving the problem of cumbersome operation in existing technologies; the overall structure supports modular pre-assembly and non-destructive operation and maintenance, improving the problem of inconvenient operation and maintenance in the later stage. Attached Figure Description

[0020] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings in the following description are merely exemplary, and those skilled in the art can derive other embodiments based on the provided drawings without creative effort.

[0021] Figure 1 This is a three-dimensional schematic diagram of the sealing structure of the present invention installed on a steel pipe pile.

[0022] Figure 2 for Figure 1Side view.

[0023] Figure 3 This is a three-dimensional schematic diagram of the sealing structure of the present invention.

[0024] Figure 4 for Figure 3 An explosion diagram.

[0025] Figure 5 for Figure 1 A longitudinal section diagram.

[0026] Figure 6 for Figure 5 Enlarged view of a portion of point A in the middle.

[0027] Figure 7 This is a longitudinal sectional view of the sealing body and the extension part structure of the present invention.

[0028] Figure 8 This is a three-dimensional schematic diagram of the support block of the present invention. Figure 1 .

[0029] Figure 9 This is a three-dimensional schematic diagram of the support block of the present invention. Figure 2 .

[0030] Figure 10 for Figure 8 Enlarged view of section B in the middle.

[0031] Figure 11 This is a three-dimensional structural diagram of the first top ring, guide post, and second top ring of the present invention.

[0032] Figure 12 This is a three-dimensional schematic diagram of the external threaded component of the present invention.

[0033] The labels in the diagram represent the following:

[0034] 1. Sealing body; 11. First sealing ring; 12. Annular groove; 13. Clearance hole; 2. Extension part; 21. Internal threaded hole; 22. Through hole; 3. Support block; 31. Inclined surface; 32. Arc-shaped anti-slip groove; 4. External threaded part; 41. Annular conical surface; 42. Butt joint structure; 43. Flange structure; 44. Through hole; 5. Second sealing ring; 6. Third sealing ring; 7. First top ring; 71. Guide post; 8. Second top ring; 81. Ball. Detailed Implementation

[0035] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0036] To address the common technical pain points of existing offshore wind turbine steel pipe pile S1 post-pile sealing structures, such as uneven locking force, insufficient sealing redundancy, single function, and difficulty in adapting to later internal maintenance needs, this invention provides a post-pile sealing structure that combines reliable sealing, convenient operation, and functional expansion.

[0037] The invention will now be fully described in conjunction with specific implementation details and practical requirements for offshore construction.

[0038] To facilitate a clear understanding of the subsequent structural description, the key concept of the steel pipe pile S1 involved in this invention will be clearly defined first.

[0039] In this invention, "the inner hole of the steel pipe pile S1" refers to the hollow channel that runs through both ends of the steel pipe pile S1, which is the core area that needs to be sealed after the pile is driven; "the inner hole port" refers to the end opening of the inner hole, which is the part where the sealing structure needs to be connected and abutted; "the inner hole port end face" refers to the end plane of the steel pipe pile S1 where the inner hole port is located, which is the mating surface for achieving end face sealing; and "the inner wall of the steel pipe pile S1" refers to the inner side wall of the inner hole, which is the abutting surface for the support block 3 to achieve radial locking.

[0040] The core design concept of this invention is to construct an integrated structure of "sealing, radial locking, drive adaptation and channel expansion". Each core component is arranged coaxially along the S1 axis of the steel pipe pile to ensure balanced force and smooth movement, while taking into account the convenience of offshore operations and the operability of later maintenance.

[0041] Reference Figures 1-8 As shown, the overall structure mainly includes the sealing body 1, the extension part 2, the support block 3, the external threaded part 4, and the docking structure 42. All components are made of Q690 high-strength steel, and the wall thickness is designed to be adapted to the S1 specification of steel pipe piles to ensure that the structural strength is sufficient to withstand harsh environments such as heavy loads at sea, high salt spray corrosion, and wind and wave impact.

[0042] From a structural perspective, the sealing body 1 serves as the front-end bearing foundation, and its lower end face is used to precisely abut against the inner hole port of the steel pipe pile S1.

[0043] The first sealing ring 11 mounted on the main body is pressed against the end face of the inner hole of the steel pipe pile S1 by the sealing body 1, which can effectively seal the gap between the upper edge of the inner hole of the steel pipe pile S1 and the sealing body 1, and achieve the sealing of the foundation end face.

[0044] The extension part 2, which is welded and fixed to the sealing body 1, extends into the inner hole of the steel pipe pile S1 in the working state. The cavity opened inside provides installation space for subsequent transmission components. The internal threaded hole 21 machined on the inner side wall of the cavity serves as the mating basis for the external threaded part 4, ensuring the stability of the threaded transmission.

[0045] The support block 3 is slidably assembled on the cavity wall of the extension part 2 along the radial direction of the steel pipe pile S1. One end of the support block can abut against the inner wall of the steel pipe pile S1, and the other end extends into the cavity and is provided with an inclined surface 31. The inclined surface 31 forms a wedge fit with the annular conical surface 41 at the bottom of the external threaded part 4, thus forming a core locking transmission mechanism.

[0046] It is worth noting that this structure can be adapted to two locking forms: single support block 3 or multiple support blocks 3. When a single support block 3 is used, the reaction force generated by it abutting against the inner wall of the steel pipe pile S1 can push the other side of the extension part 2 to simultaneously press against the inner wall of the steel pipe pile S1, so as to achieve stable locking. When two or more support blocks 3 are used, each support block 3 is evenly distributed around the axis of the steel pipe pile S1, which can further improve the balance of locking force and avoid sealing failure caused by the displacement of the sealing body 1.

[0047] The outer circumference of the external threaded part 4 is machined with threads that are compatible with the internal threaded hole 21, and its axis is collinear with the axis of the steel pipe pile S1. When rotating, it can move up and down along the axis. The bottom annular conical surface 41 presses the inclined surface 31 of the support block 3, driving the support block 3 to extend or retract radially.

[0048] The mating structure 42, fixed to the top of the external threaded part 4, is used to drive the external threaded part 4 to rotate around its own axis.

[0049] Correspondingly, the sealing body 1 is provided with a clearance hole 13. The clearance hole 13 not only provides sufficient operating space for the docking of the external drive component and the docking structure 42, but its projection along the axis of the external thread component 4 also covers the movement range of the docking structure 42, which can be compatible with two docking forms that are protruding outward or recessed inward, thus improving the drive adaptability.

[0050] Reference Figure 6 and Figure 12 As shown, to further optimize the sealing performance, the present invention adds a redundant protective structure on top of the basic seal.

[0051] A flange structure 43 is formed radially extending from the top outer periphery of the external threaded part 4. The bottom surface of the flange structure 43 is higher than the upper end surface of the sealing body 1. A second sealing ring 5 is provided in the reserved installation gap between the two, forming a double protection of "end face sealing + gap sealing". This can effectively prevent marine salt spray, water vapor or impurities from seeping into the interior through the gap between the clearance hole 13 and the external threaded part 4, protecting the thread fit accuracy and the service life of the component.

[0052] The second sealing ring 5 is preferably made of fluororubber, which is suitable for harsh marine environments. It achieves pre-compression through the axial pressing of the flange structure 43 to ensure sealing reliability.

[0053] The flange structure 43 can be integrally forged with the external threaded part 4, or it can be detachably connected with bolts. The integrally formed structure has higher strength, while the detachable structure facilitates the replacement and maintenance of the sealing ring in the later stage. Those skilled in the art can choose according to actual needs.

[0054] Reference Figure 1 and Figure 5 As shown, the docking structure 42 can adopt a variety of practical forms to adapt to the docking drive.

[0055] The preferred solution is a large polygonal boss protruding from the top of the external threaded part 4, which is integrally forged with the external threaded part 4. Its size is designed according to the high torque requirements of offshore operations, and it can be directly adapted to the large hydraulic torque wrenches commonly used in offshore operations. No special customized tools are required, which improves the convenience and efficiency of offshore operations.

[0056] The polygonal structure and the surface contact of the drive components can effectively disperse stress, avoid local damage during the drive process, and ensure uniform torque transmission.

[0057] In addition, the docking structure 42 can also adopt a recessed large polygonal groove on the top of the external threaded part 4. This design can prevent the docking structure 42 from being exposed and damaged by collision, adapt to the working scene with limited space, and at the same time adapt to the special connector of large hydraulic wrench to ensure stable transmission of large torque.

[0058] All variations can achieve stable torque transmission without deviating from the core design concept of this invention. (Refer to...) Figure 5 As shown, the docking structure can be installed on the end cap structure that can be flipped open, which does not affect the rotation of the external threaded part 4 and is also convenient to open and close, making it convenient for subsequent entry operations.

[0059] Reference Figure 7 As shown, in order to improve the smoothness of the sliding of the support block 3 and avoid jamming during locking or unlocking, the present invention adds a guide structure at the mating point between the extension part 2 and the support block 3.

[0060] Specifically, a through hole 22 is opened in the cavity wall of the extension part 2 along the radial direction of the steel pipe pile S1. The support block 3 is inserted into the through hole 22, and the two are slidably engaged by a slide rail 23. Preferably, a T-shaped slide rail 23 structure is adopted. Through the precise engagement of the boss and the groove, the other degrees of freedom of the support block 3 except for radial sliding are restricted. The engagement gap is controlled within a reasonable range, which ensures smooth sliding and avoids radial movement.

[0061] This guiding design effectively reduces sliding resistance, ensuring that the driving torque of the external threaded part 4 is efficiently transmitted to the support block 3, while making the extension and retraction trajectory of the support block 3 more precise, thus improving the reliability of locking and unlocking.

[0062] Alternatively, a dovetail groove slide rail 23 or a linear bearing combined with an optical shaft can be used. The former has higher guiding accuracy, while the latter has lower sliding resistance. The choice can be made flexibly according to the operational requirements.

[0063] Reference Figure 9 As shown, at one end of the support block 3 that abuts against the inner wall of the steel pipe pile S1, arc-shaped anti-slip grooves 32 are provided at intervals along the axis of the steel pipe pile S1. This design can effectively increase the static friction between the support block 3 and the inner wall of the steel pipe pile S1 and improve the locking stability.

[0064] The curvature of the arc-shaped anti-slip groove 32 is matched with the curvature of the inner wall of the steel pipe pile S1 to ensure that the two are in surface contact and avoid local stress concentration.

[0065] When the support block 3 is pressed against the inner wall of the steel pipe pile S1, the tiny protrusions on the inner wall of the steel pipe pile S1 will be embedded in the anti-slip groove, forming a mechanical interlock. This can effectively resist the vibration and impact generated by the operation of the offshore wind turbine, prevent the support block 3 from loosening, and at the same time, it will not scratch the anti-corrosion coating on the inner wall of the steel pipe pile S1, thus balancing the locking effect and structural protection.

[0066] To further enhance the redundancy of the end face seal and to accommodate potential unevenness defects on the S1 end face of the steel pipe pile, this invention also designs an auxiliary sealing structure.

[0067] Reference Figure 6 , Figure 10 and Figure 11 As shown, an annular groove 12 is coaxially formed at the lower end of the sealing body 1 along the axial direction. A third sealing ring 6 that can extend along the axial direction of the sealing body 1 is provided in the groove. A first top ring 7 that can move along the axial direction is provided between the bottom of the annular groove 12 and the third sealing ring 6. A guide post 71 that penetrates the sealing body 1 extends axially from the upper end of the first top ring 7. At least two guide posts 71 are provided and are evenly distributed around the axis of the first top ring 7.

[0068] When the external threaded part 4 moves downward in the axial direction, the flange structure 43 at its top will squeeze the top of the guide post 71, push the first top ring 7 downward, and then press the third sealing ring 6 against the end face of the steel pipe pile S1, forming a double end face seal of "first sealing ring 11 + third sealing ring 6". Even if the first sealing ring 11 wears out due to long-term use, the third sealing ring 6 can still ensure the sealing effect.

[0069] To ensure that all guide posts 71 are subjected to force synchronously and to prevent the first top ring 7 from tilting, a second top ring 8 can be coaxially set above the sealing body 1. The top of all guide posts 71 is fixedly connected to the bottom of the second top ring 8. The flange structure 43 pushes all guide posts 71 to move downward synchronously by abutting against the upper end of the second top ring 8, further improving the force balance.

[0070] In addition, at the contact point between the flange structure 43 and the second top ring 8, ball bearings 81 can be arranged in a ring array, or a rotating collar can be arranged to convert sliding friction into rolling friction, effectively reducing the driving torque and making the external threaded part 4 rotate more smoothly, which is suitable for high torque driving scenarios.

[0071] Reference Figure 5 and Figure 12 As shown, considering the need for internal maintenance of the steel pipe pile S1 in the later stage, the present invention has carried out a channel expansion design on the external threaded part 4, setting it as a hollow structure with open ends. At the same time, a through hole 44 is opened in the center of the annular cone surface 41. The through hole 44 has the same diameter as the internal hollow channel of the external threaded part 4, and the diameter is designed to allow people to pass through, which is fully suitable for adults to enter the steel pipe pile S1 for internal maintenance.

[0072] The core advantage of this design is that it utilizes the structural space of the external threaded part 4 to construct a maintenance channel, eliminating the need to drill additional holes in the sealing body 1 or the steel pipe pile S1. This ensures the integrity of the overall structure and achieves the integrated function of "sealing + channel".

[0073] During later maintenance, personnel can enter the hollow channel of the external threaded part 4 through the avoidance hole 13 on the sealing body 1, and then enter the interior of the steel pipe pile S1 through the hole 44. There is no need to disassemble the sealing structure, which effectively reduces the risk and maintenance cost of high-altitude operations at sea.

[0074] When no maintenance or passage is required, a removable sealing plug can be installed at the through hole 44. The sealing plug is connected to the through hole 44 by a thread and an additional sealing ring is added to ensure the sealing performance of the sealing structure and realize flexible switching of functions.

[0075] Based on the above structural design, the construction process of this invention needs to be combined with the offshore operation scenario and relies on large equipment and standardized operation. The specific implementation process is as follows:

[0076] The first stage is the land-based pre-assembly stage. In the near-shore prefabrication yard, a 100-ton gantry crane is used to lift and align the external threaded part 4 with the extension part 2. With the help of auxiliary tools, the threads are manually pre-spun to retract the support block 3 to the initial position, thus completing the assembly of the plug-in unit.

[0077] After assembly, the coaxiality of each component is calibrated using a total station to ensure that the deviation is controlled within the allowable range and to avoid jamming during later installation.

[0078] Subsequently, the pre-assembled plug-in unit was transported and hoisted at sea to the engineering barge. After being transported to the pile driving operation area, a 250-ton floating crane equipped with special hoisting slings was used to hoist the plug-in unit from the barge to the top of the steel pipe pile S1 that had been driven. The laser positioning instrument was used to accurately align the plug-in unit with the inner hole of the steel pipe pile S1 and slowly lower it so that the sealing body 1 initially fits against the end face of the steel pipe pile S1, thus completing the positioning.

[0079] The next step is the pre-compression sealing stage. By using the slight downward force of the floating crane hook, or in conjunction with the hydraulic jack, an axial compression force is applied to the sealing body 1, so that the first sealing ring 11 is pre-compressed, initially blocking the entry of external moisture and impurities, and completing the basic sealing.

[0080] Then, the core locking operation is carried out. A hydraulic torque wrench with a torque of more than 2000 N·m is used. The appropriate connector is selected according to the form of the docking structure 42. After the connector is put into the docking structure 42, the external threaded part 4 is driven to rotate in stages.

[0081] First, pre-rotate with 50% of the rated torque to confirm that the support block 3 slides smoothly without jamming and that all components move smoothly; then apply 100% of the rated torque to drive the external threaded part 4 to move axially downward, and press the inclined surface 31 of the support block 3 through the annular conical surface 41 to push the support block 3 to extend radially until the support block 3 presses against the inner wall of the steel pipe pile S1.

[0082] If a multi-support block 3 structure is adopted, the abutment force of each support block 3 can be detected by a pressure sensor to ensure that the pressure difference is controlled within 5%, ensuring balanced force, and finally achieving axial locking of the sealing body 1 by means of extrusion force and friction force, thus completing the sealing operation.

[0083] During disassembly, simply use a hydraulic torque wrench to reverse drive the external threaded part 4 through the docking structure 42, causing it to move axially upward. The annular cone surface 41 will disengage from the inclined surface 31 of the support block 3. Under its own weight or the action of the reset mechanism, the support block 3 will radially retract and disengage from the inner wall of the steel pipe pile S1. After unlocking, the plug-in unit can be lifted and removed by a floating crane at sea.

[0084] When personnel need to go down for maintenance later, the temporary sealing cover at the avoidance hole 13 is opened, and the personnel are secured with safety ropes and enter the interior of the steel pipe pile S1 through the hollow channel of the external threaded part 4 and the through hole 44. The entire operation is protected by the offshore operation platform to ensure the safety of the operation.

[0085] In summary, this invention achieves multiple technical advantages through the synergistic combination of core structure and optimized design.

[0086] Firstly, it addresses the core issues of traditional sealing structures. Through coaxial arrangement and wedge-shaped transmission mechanism, it adapts to single / multiple support block 3 locking forms, effectively improving the problem of seal ring slippage caused by uneven locking. The collaborative design of multiple sealing structures enhances sealing redundancy and can stably adapt to harsh marine environments. Secondly, it improves the convenience of marine operations. The integrated plug-in unit design allows for pre-assembly on land, reducing marine operation time. The docking structure 42, which adapts to large hydraulic equipment, requires no special tools, reducing operational difficulty. Thirdly, it strengthens structural reliability. The guide rail 23, evenly distributed guide posts 71 and top ring, and rolling friction conversion design ensure smooth movement and balanced force distribution of each component, reducing wear and extending long-term service life at sea. Fourthly, it expands functional practicality. The maintenance channel constructed by the large-size hollow external threaded component 4 realizes the synergy between sealing and maintenance. Subsequent internal inspection and maintenance can be completed without disassembly, effectively reducing operation and maintenance costs.

[0087] This invention breaks through the design limitations of existing technologies, such as "locking structure and sealing structure being independent" and "blocking structure having a single function". It proposes an integrated design concept of "locking-sealing-functional expansion" and forms a corresponding technical solution for common industry problems such as "difficulty in balancing sealing reliability and operational convenience of marine blocking structures" and "difficulty in coordinating blocking and maintenance".

[0088] This invention can be widely adapted to offshore wind turbine steel pipe piles S1 of different diameters. The overall structure is reasonably designed, easy to construct, and highly reliable. It can effectively shorten the single pile sealing operation time, reduce the probability of sealing failure, and take into account both sealing function and subsequent operation and maintenance needs.

[0089] The above embodiments are merely exemplary embodiments of the present invention and are not intended to limit the present invention. The scope of protection of the present invention is defined by the claims. Those skilled in the art can make various modifications or equivalent substitutions to the present invention within its spirit and scope of protection, and such modifications or equivalent substitutions should also be considered to fall within the scope of protection of the present invention.

Claims

1. A post-pile driving sealing structure for offshore wind turbine steel pipe piles, characterized in that, include: A sealing body (1) is used to abut against the inner hole port of the steel pipe pile (S1); a first sealing ring (11) is provided on the sealing body (1), and the sealing body (1) can press the first sealing ring (11) against the end face of the inner hole port of the steel pipe pile (S1), and the first sealing ring (11) seals the gap between the upper edge of the inner hole of the steel pipe pile (S1) and the sealing body (1); The extension part (2) is fixedly connected to the sealing body (1) and can be inserted into the inner hole of the steel pipe pile (S1) when the sealing body (1) is in operation. The extension part (2) has a cavity inside, and the inner side wall of the cavity is provided with an internal thread hole (21). A support block (3) is slidably disposed on the cavity wall of the extension part (2) along the radial direction of the steel pipe pile (S1). The support block (3) has a first end that can abut against the inner wall of the steel pipe pile (S1) and a second end that extends into the cavity of the extension part (2). The second end has an inclined surface (31). There is at least one support block (3). When there is only one support block (3), the reaction force generated by the support block (3) abutting against the inner wall of the steel pipe pile (S1) can push the other side of the extension part (2) to press against the inner wall of the steel pipe pile (S1). When there are two or more support blocks (3), each support block (3) is evenly distributed around the axis of the steel pipe pile (S1). The external threaded part (4) has a thread on its outer circumference and is threaded to the internal threaded hole (21). The axis of the external threaded part (4) is collinear with the axis of the steel pipe pile (S1). The bottom end of the external threaded part (4) is provided with an annular conical surface (41). When the external threaded part (4) moves axially relative to the internal threaded hole (21), the annular conical surface (41) cooperates with the inclined surface (31) of the support block (3) to drive the support block (3) to extend radially and abut against the inner wall of the steel pipe pile (S1). The docking structure (42) is fixedly installed on the top of the external threaded part (4) and can drive the external threaded part (4) to rotate around its own axis. The sealing body (1) is provided with a clearance hole (13) that allows the external driving part to dock with the docking structure (42). The projection of the clearance hole (13) along the axis of the external threaded part (4) covers the range of motion of the docking structure (42).

2. The post-pile driving sealing structure for offshore wind turbine steel pipe piles according to claim 1, characterized in that, The external threaded part (4) has a flange structure (43) extending radially from the top outer periphery. The bottom surface of the flange structure (43) is higher than the upper end surface of the sealing body (1). A second sealing ring (5) is provided between the bottom surface of the flange structure (43) and the upper end surface of the sealing body (1). The second sealing ring (5) is used to seal the gap between the flange structure (43) and the sealing body (1).

3. The post-pile driving sealing structure for offshore wind turbine steel pipe piles according to claim 1, characterized in that, The docking structure (42) is a structure that protrudes from or is recessed into the top region of the external threaded component (4); the docking structure (42) is a single structure coaxially disposed on the top of the external threaded component (4), and its cross-section is a polygonal or irregular structure; or the docking structure (42) has at least two docking points, and at least one of the docking points is eccentrically disposed relative to the axis of the external threaded component (4); or the docking structure (42) is a rod-shaped, block-shaped, or irregular handle structure that protrudes from the top region of the external threaded component (4).

4. The post-pile driving sealing structure for offshore wind turbine steel pipe piles according to claim 1, characterized in that, The cavity wall of the extension part (2) is provided with a through hole (22) along the radial direction of the steel pipe pile (S1). The support block (3) is inserted into the through hole (22), and the support block (3) and the through hole (22) are slidably engaged by a slide rail.

5. The post-pile driving sealing structure for offshore wind turbine steel pipe piles according to claim 1, characterized in that, At the first end of the support block (3) that contacts the inner wall of the steel pipe pile (S1), arc-shaped anti-slip grooves (32) are provided at intervals along the axial direction of the steel pipe pile (S1).

6. A post-pile driving sealing structure for offshore wind turbine steel pipe piles according to claim 2, characterized in that, The lower end of the sealing body (1) is coaxially provided with an annular groove (12) along its axial direction, and a third sealing ring (6) that can extend along the axial direction of the sealing body (1) is provided in the annular groove (12). A first top ring (7) that can move along the axis of the sealing body (1) is provided between the bottom of the annular groove (12) and the third sealing ring (6). The upper end of the first top ring (7) extends axially through the sealing body (1) and a guide post (71) penetrates the sealing body (1). There are at least two guide posts (71), and each guide post (71) is evenly distributed around the axis of the first top ring (7). The flange structure (43) can press the top of the guide post (71) to push the first top ring (7) when the external threaded part (4) moves axially, thereby abutting the third sealing ring (6) against the end face of the steel pipe pile (S1).

7. A post-pile driving sealing structure for offshore wind turbine steel pipe piles according to claim 6, characterized in that, A second top ring (8) is coaxially arranged above the sealing body (1). The bottom of the second top ring (8) is fixedly connected to the top of all the guide posts (71). The flange structure (43) can abut against the upper end of the second top ring (8) to push all the guide posts (71) to move synchronously downward along the axial direction.

8. A post-pile driving sealing structure for offshore wind turbine steel pipe piles according to claim 7, characterized in that, The flange structure (43) is provided with a ring array of balls (81) at the point where it contacts the second top ring (8) to convert sliding friction into rolling friction; or it is provided with a rotating collar that abuts against the top of the second top ring (8).

9. A post-pile driving sealing structure for offshore wind turbine steel pipe piles according to claim 1, characterized in that, The external threaded component (4) is a hollow structure with openings at both ends; the center of the annular conical surface (41) has a through hole (44), which connects the internal space of the external threaded component (4) and the inner hole of the steel pipe pile (S1).

10. A construction method for a post-driving sealing structure for offshore wind turbine steel pipe piles, used in any one of claims 1-9, characterized in that, Includes the following steps: S1. Pre-assemble the external threaded part (4) and the extension part (2) so that the support block (3) is in a retracted state, forming a plug-in unit; S2. The plug-in unit is hoisted and plugged into the inner hole port of the steel pipe pile (S1) after the pile driving is completed, so that the sealing body (1) initially fits the end face of the inner hole port of the steel pipe pile (S1). S3. Apply a clamping force toward the steel pipe pile (S1) to the sealing body (1) to pre-compress the first sealing ring (11) to achieve preliminary end face sealing. S4. The external drive unit is connected to the external threaded part (4) through the docking structure (42), and the external threaded part (4) is driven to rotate around its own axis, so that the external threaded part (4) moves axially downward relative to the internal threaded hole (21) of the extension part (2). S5. The annular conical surface (41) at the bottom of the external threaded part (4) moves down and presses the inclined surface (31) of the support block (3), pushing the support block (3) to extend the extension part (2) radially along the steel pipe pile (S1) until the support block (3) abuts against the inner wall of the steel pipe pile (S1); when there is one support block (3), the support block (3) abuts against the reaction force to push the other side of the extension part (2) to abut against the inner wall of the steel pipe pile (S1); when there are two or more support blocks (3), each support block (3) is evenly subjected to force to abut against the inner wall of the steel pipe pile (S1), and the axial locking of the sealing body (1) is achieved by means of the extrusion force and friction force, thus completing the sealing operation; S6. During disassembly, the external threaded part (4) is driven to rotate in the opposite direction by the docking structure (42), so that the external threaded part (4) moves upward axially, the annular cone surface (41) separates from the inclined surface (31) of the support block (3), the support block (3) retracts radially and separates from the inner wall of the steel pipe pile (S1), and the plug-in unit can be hoisted out after the lock is released.

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