Construction process of steel pile type offshore wind power jacket tp transition section

Abstract

The application discloses a steel pile type offshore wind power guide pipe support TP transition section construction process and belongs to the technical field of offshore wind power, solves the problems of low construction precision, poor efficiency, insufficient structural durability and inability to batch construction of traditional processes. The process completes the standardized prefabrication of the transition section bottom plate, inclined beam and edge column, TP cylinder and flange, inner and outer platforms and accessories in turn, then carries out TP transition section overall assembly, and finally carries out whole-process size and geometric tolerance control; each prefabrication process adopts targeted welding, positioning and turning process, the fatigue position node is polished in the assembly stage to avoid stress concentration, and the tolerance control formulates exclusive requirements for different joints and components. The application realizes independent and orderly connection of each process, improves the component manufacturing and overall assembly precision, enhances the structural durability of the TP transition section, guarantees the accurate butt joint of the TP transition section with the wind turbine tower cylinder and the guide pipe support, provides support for batch construction, and greatly improves the construction efficiency and reduces the construction cost.

Description

Technical Field

[0001] This invention relates to the field of offshore wind power technology, specifically to a construction process for a steel pile type offshore wind turbine jacket TP transition section. Background Technology

[0002] In the construction of offshore wind power projects, the jacket is one of the core structures of the offshore wind power foundation. The TP transition section, as a key component installed on the top of the jacket, is an important transition structure connecting the wind turbine tower and the jacket. Its construction quality and dimensional accuracy directly determine the installation compatibility of the wind turbine tower and the overall structural stability of the offshore wind power foundation.

[0003] The TP transition section not only needs to provide standard interface flanges for the wind turbine tower to achieve precise docking, but also needs to safely and effectively transfer the complex dynamic loads such as wind load, wave force, and gravity generated during wind turbine operation to the jacket structure and steel piles. At the same time, the TP transition section integrates internal and external operating platforms and various operation and maintenance accessories, providing the necessary operating space for offshore construction, equipment installation and subsequent operation and maintenance.

[0004] The existing construction process for steel pile offshore wind turbine jacket (TP) transition sections has many shortcomings. The prefabrication of various components lacks standardized procedures, making it difficult to control the connection accuracy of various structures during overall assembly. Dimensional and geometric tolerances frequently exceed design requirements, leading to difficulties in connecting flanges to the wind turbine tower and reduced load transfer efficiency. Furthermore, the traditional construction process has unreasonable connections between various procedures, and the quality control during the prefabrication and assembly stages lacks systematicity, making it impossible to achieve mass production. This results in low construction efficiency and high costs. In addition, some welding nodes have not been specifically treated, which can easily lead to stress concentration, affecting the structural durability of the TP transition section and making it difficult to meet the construction requirements of deep-sea, high-power offshore wind power projects.

[0005] To address the aforementioned technical issues, this invention proposes a construction process for the TP transition section of a steel pile offshore wind turbine jacket. By standardizing and prefabricating various components such as the transition section base plate, inclined beams and side columns, TP cylinder and flanges, and inner and outer platforms, the overall assembly process is optimized, and a full-process dimensional and geometric tolerance control system is established. This effectively improves the construction accuracy and quality of the TP transition section, enables mass production, significantly increases construction efficiency, and reduces construction costs. Summary of the Invention

[0006] To address the aforementioned technical problems, this invention provides a construction process for a steel pile-type offshore wind turbine jacket (TP) transition section, comprising the following steps: S100: Prefabrication of the transition section bottom plate. Steel plates are assembled and welded to form the transition section bottom plate, and a U-shaped beam is installed at the bottom of the bottom plate. After the full penetration welding of the transition section bottom plate and the U-shaped beam is completed, the transition section bottom plate is hoisted and placed on the tooling. S200: Prefabricate the inclined beams and side columns, weld the joints of the upper flange plates of the inclined beams together, then weld the upper flange plates of the inclined beams to the web plates together, and finally install and fully weld the side columns. S300: Prefabrication of TP cylinder and flange. The TP flange is hoisted into place and its dimensions are checked. Multiple cylinder sections are then butt-welded onto the TP flange one by one to form a TP cylinder structure with flange. S400: Prefabrication of inner and outer platforms and other accessories, including the layered assembly prefabrication of the inner platform and the prefabrication of the outer platform and door panels; S500: The TP transition section is assembled as a whole. The TP cylinder is assembled with the transition section bottom plate, the internal support of the TP cylinder is installed, the TP cylinder body is cut and the door panel is installed, the TP cylinder, outer platform and inclined beam are assembled, the fatigue position nodes are ground after dimensional control adjustment and welding, the internal support of the TP cylinder is removed and the inner platform and various electrical instruments and structural accessories are installed, and finally the relevant accessories of the outer platform are installed. S600: TP transition section dimensional control, which controls the dimensions and geometric tolerances of each prefabrication and assembly stage of the TP transition section to ensure that it meets the requirements of the design drawings and relevant standards.

[0007] In some feasible embodiments, in S100, the steel plate assembly welding adopts a multiple-turning method, and the joints of different parts of the base plate are welded on both sides respectively. The U-shaped beam and the base plate adopt single-sided full penetration welding to avoid subsequent deformation of the base plate and enhance the local strength of the base plate.

[0008] In some feasible embodiments, S100 also includes the fabrication process of the outer platform, which involves welding the steel plates of the outer platform together, installing a U-shaped beam at the outer platform, and after completing the double-sided welding of the outer platform and the U-shaped beam, assembling the outer platform and the transition section bottom plate together and completing the double-sided welding.

[0009] In some feasible embodiments, in S200, before splicing the upper flange plate of the assembly beam, lines are marked and braces are welded to control the splice size. After welding one side of the upper flange plate splice of the assembly beam, auxiliary lifting points are welded on the assembly beam. The assembly beam is then turned over using the auxiliary lifting points and the other side of the splice is welded.

[0010] In some feasible embodiments, in S300, after the first section of the cylinder is hoisted to the TP flange, it is first spot welded and fixed, and then it is turned over and placed on the rotating platform to complete the full welding. Subsequent sections of the cylinder are hoisted onto the rotating platform and assembled with the previous section of the cylinder. After verifying that the assembly dimensions are qualified, the full welding operation is carried out.

[0011] In some feasible embodiments, in S400, the prefabrication of the inner platform includes the following steps: cutting steel plates and prefabricating the steel plates, railings and hinges required for the inner platform; hot-dip galvanizing all steel structures; assembling the bottom, middle and top platforms of the inner platform in sequence on the prefabrication fixtures, and installing the grilles, columns and accessories layer by layer; removing the removable grilles on the inner platform and folding the hinge beams of the inner platform to prepare for the subsequent hoisting operation of the inner platform.

[0012] In some feasible embodiments, in S500, after the TP cylinder, outer platform and inclined beam are assembled and welded, all nodes at fatigue locations are ground to avoid stress concentration. After grinding, the internal support of the TP cylinder is removed.

[0013] In some feasible embodiments, during the installation of the inner platform in S500, the internal support of the inner platform is installed using assembly tooling. After the inner platform is hoisted to the TP cylinder and the assembly dimensions are adjusted, the inner platform is fixed by applying torque with bolts. After the inner platform is in place, the dehumidification pipe, elevator accessories, electrical equipment, cable trays, cables and aluminum ladders are installed simultaneously, and the position, size and flatness of the electrical equipment brackets are checked to avoid collisions between the electrical equipment.

[0014] In some feasible embodiments, during the installation of external platform accessories in S500, railings, cranes, electrical boxes and hydraulic hoses are installed in sequence, hydraulic pipe pressure testing and oil connection are completed, the orientation of the crane arm is controlled to avoid interference with the mooring components, and finally the ventilation pipes are installed; at the same time, safety sign stickers, back panels and safety equipment and supporting brackets are installed simultaneously.

[0015] In some feasible embodiments, in S600, the alignment tolerance control of the butt joint follows the following requirements: not exceeding 0.15 times the smaller thickness of the discontinuous plate or 4 mm, whichever is smaller; the eccentricity of the cross joint is controlled according to the thickness of the continuous plate, and when the thickness difference of discontinuous plates of different thicknesses exceeds a specified value, the cross section of the thinner member is completely within the cross section of the thicker member.

[0016] In some feasible embodiments, in S600, specific dimensional and geometric tolerance control requirements are formulated for the transition section base plate, U-beam, inclined beam, side column, TP cylinder, flange and inner and outer platforms, and the tolerance control work is carried out throughout the entire prefabrication and final assembly cycle.

[0017] In some feasible embodiments, in S600, after the flange is prefabricated, its outer diameter, thickness, upper surface flatness, surface roughness, bolt hole positioning, hole diameter and edge chamfer are all subject to tolerance control to ensure that the flange meets the accuracy requirements for connection with the wind turbine tower.

[0018] The beneficial effects of this invention are as follows: (1) The present invention divides the construction of the TP transition section into multiple standardized prefabrication processes and overall assembly processes. Each process is carried out independently and is connected in an orderly manner, which greatly improves the construction efficiency and provides process support for the mass construction of the TP transition section of the steel pile offshore wind turbine jacket, effectively reducing the construction cost. (2) Targeted welding, positioning and flipping processes were adopted during the prefabrication of each component, which reduced structural deformation, improved the manufacturing accuracy of individual components, and laid the foundation for the precise docking of the subsequent overall assembly. (3) During the overall assembly stage, the fatigue location nodes are ground to avoid stress concentration and improve the structural durability and service life of the TP transition section. (4) A full-process dimensional and geometric tolerance control system was established, and exclusive tolerance requirements were formulated for each prefabricated component and the overall assembly structure to ensure that the overall dimensional accuracy of the TP transition section meets the design drawings and relevant standard requirements, ensuring accurate docking with the wind turbine tower and jacket, and improving the overall structural stability of the offshore wind power foundation. (5) The prefabrication and installation process of internal and external platforms and various accessories is standardized, which ensures the practicality of operation and maintenance space and the compatibility of installation of various equipment, and provides convenience for subsequent offshore construction and later operation and maintenance. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the overall structure of the TP transition section of the steel pile offshore wind turbine jacket in an embodiment of the present invention; Figure 2 This is a schematic diagram of the process flow for the overall assembly of the TP transition section in an embodiment of the present invention.

[0021] Attached reference numerals: 1. Transition section base plate; 2. U-shaped beam; 3. Inclined beam; 4. Side column; 5. TP cylinder; 6. TP flange; 7. Inner platform; 8. Outer platform; 9. Door panel; 13. Aluminum straight ladder; 14. Railing; 15. Crane; 16. Ventilation pipe. Detailed Implementation

[0022] 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.

[0023] Reference Figure 1 and Figure 2 The illustrated construction process for a steel-piled offshore wind turbine jacket (TP) transition section is based on standardized prefabrication, meticulous assembly, and full-process dimensional control to achieve high-precision and high-efficiency construction of the TP transition section. Specifically, it includes the following steps: S100: Precast transition section bottom plate 1 The transition section base plate 1 serves as the bottom reference surface for the TP transition section construction. Its flatness and structural strength directly affect the assembly accuracy of subsequent components. Therefore, this step employs steel plate assembly and welding to fabricate the transition section base plate 1, and installs U-shaped beams 2 to enhance structural performance. In practice, steel plates of the corresponding specifications are selected according to the design drawings. The steel plates are then assembled on prefabricated fixtures. After determining the positions of the joints, the joints at different locations on the base plate are double-sided welded using a multi-turning method. This welding method improves the penetration at the joints, avoiding defects such as weld beads and incomplete penetration caused by single-sided welding, while also reducing deformation of the base plate due to welding stress.

[0024] After the main body of the transition section base plate 1 is welded, a U-shaped beam 2 is installed at a predetermined position at the bottom of the transition section base plate 1. The U-shaped beam 2 and the transition section base plate 1 are connected by a single-sided full penetration weld. This welding method ensures welding strength and enhances the structural strength of the base plate, while effectively preventing deformation of the transition section base plate 1 due to structural stress or external forces. After the full penetration weld between the transition section base plate 1 and the U-shaped beam 2 is completed and passes the welding quality inspection, the transition section base plate 1 is smoothly hoisted onto a special tooling using specialized hoisting equipment, preparing it for subsequent assembly with other components.

[0025] In some embodiments of this step, the fabrication process of the outer platform 8 is also included. The outer platform 8 provides external operating space for offshore operations and maintenance. Its fabrication needs to be completed simultaneously with the main body of the transition section bottom plate 1 to ensure docking accuracy. First, the steel plates required for the outer platform 8 are spliced ​​and welded on prefabricated fixtures, and the splicing welding quality is ensured according to the fabrication standards of the transition section bottom plate 1. Then, U-shaped beams 2 are installed at the preset positions of the outer platform 8, and double-sided welding of the outer platform 8 and U-shaped beams 2 is completed to ensure the structural strength of the outer platform 8. Finally, the fabricated outer platform 8 and the transition section bottom plate 1 are precisely assembled and double-sided welded to form an integrated structure, avoiding docking deviations during subsequent assembly.

[0026] S200: Precast inclined beam 3 and side column 4 The inclined beam 3 and the side column 4 form the spatial support structure of the TP transition section, responsible for distributing and transferring the concentrated load of the TP cylinder 5 to the jacket. Therefore, its prefabrication process requires strict control of the joint size and welding quality. This step first involves the prefabrication of the inclined beam 3. First, the upper flange plate of the inclined beam 3 is cut. According to the dimensional requirements of the design drawings, lines are marked at the joint position of the flange plate in advance to clarify the joint connection benchmark. At the same time, bracing is welded on both sides of the joint to position and fix the flange plate, effectively controlling the joint size and avoiding misalignment during assembly.

[0027] After assembling the upper flange plate, weld one side of the joint first. After the weld cools and passes inspection, weld auxiliary lifting points at the preset positions of the inclined beam 3. The placement of the auxiliary lifting points must ensure that the inclined beam 3 is subjected to uniform force during the flipping process to prevent deformation or damage. Use the auxiliary lifting points to smoothly flip the inclined beam 3, and then weld the other side of the joint to achieve double-sided welding of the upper flange plate joint and ensure weld strength.

[0028] After completing the splicing welding of the upper flange plate of the inclined beam 3, the upper flange plate and the web plate are precisely assembled and then fully welded to form an integrated main structure of the inclined beam 3. After the main welding of the inclined beam 3 is completed and the inspection is qualified, the side column 4 is hoisted to the preset node of the inclined beam 3 according to the position requirements of the design drawings and fully welded to firmly connect the side column 4 with the inclined beam 3, thus completing the prefabrication of the inclined beam 3 and the side column 4. The prefabricated structure needs to be placed on a special support to avoid deformation due to its own weight.

[0029] S300: Prefabricated TP cylinder 5 and flange TP cylinder 5 and flange are core components connecting the wind turbine tower. The dimensional accuracy of TP flange 6 and the welding quality between TP cylinder 5 and flange directly determine the docking effect with the wind turbine tower. This step uses a segmented assembly welding method to fabricate the TP cylinder 5 structure with flange. First, TP flange 6 is precisely hoisted to the preset position of the prefabricated fixture using hoisting equipment. After positioning, a comprehensive inspection of key dimensions such as the outer diameter, thickness, and flatness of TP flange 6 is immediately carried out to ensure that its dimensions meet the design requirements. If there are any dimensional deviations, they must be adjusted in time to avoid affecting the subsequent assembly accuracy of the cylinder sections.

[0030] After the TP flange 6 dimensions pass inspection, the first cylinder section is hoisted to the pre-set assembly position of the TP flange 6. First, the first cylinder section and the TP flange 6 are temporarily fixed together using spot welding. The spot weld points must be evenly distributed to ensure the stability of the temporary fixation. Then, the TP flange 6 and the first cylinder section, after being spot-welded, are flipped over and placed on a special rotating platform. The rotation function of the platform is used to complete the full welding operation between them, making the welding operation angle more reasonable and ensuring the uniformity and penetration of the weld.

[0031] After the welding of the first section of the cylinder to TP flange 6 is completed and passes inspection, the assembly welding of subsequent cylinder sections begins. Each subsequent cylinder section must be hoisted onto a rotating platform and precisely assembled with the previously welded cylinder section. After assembly, the assembly dimensions are verified to ensure that the coaxiality, butt joint clearance, and other indicators of the cylinder sections meet the design requirements before full welding is carried out. All cylinder sections are assembled and welded in sequence to finally form the TP cylinder 5 structure with flange. After welding, the overall roundness and straightness of TP cylinder 5 must be inspected to ensure that the structure meets the requirements for subsequent assembly.

[0032] S400: Prefabricated internal and external platforms and other accessories The inner and outer platforms 8 and other accessories are the maintenance support structures for the TP transition section. In this step, the inner platform 7 is prefabricated separately from the outer platform 8, door panels 9, and other accessories, which improves prefabrication efficiency and ensures the manufacturing accuracy of each component. In the prefabrication process of the inner platform 7, which is usually a multi-layer structure, to ensure its corrosion resistance and structural strength, the steel plates are first precisely cut, and various components such as steel profiles, railings 14, and hinges required for the inner platform 7 are prefabricated at the same time. After all steel structure components are completed, they are uniformly hot-dip galvanized to form an anti-corrosion layer, thereby extending the service life of the inner platform 7 in the harsh marine environment.

[0033] After hot-dip galvanizing, the inner platform 7 is prefabricated in layers on a special prefabrication fixture. According to the design drawings, the bottom platform of the inner platform 7 is assembled first. After the bottom platform is assembled, the grid, columns and accessories are installed layer by layer to ensure that the grid of each platform is laid flat and the columns are firmly fixed. Then the middle platform and the top platform are assembled and the accessories are installed in sequence, so that the inner platform 7 forms an integrated multi-layer structure.

[0034] To facilitate the subsequent hoisting operation of the inner platform 7 into the TP cylinder 5, after the inner platform 7 is prefabricated, the removable grid on the platform is removed to reduce the weight during hoisting. At the same time, the hinge beam of the inner platform 7 is folded to reduce the overall space occupied by the inner platform 7, avoid interference with the inner wall of the TP cylinder 5 during hoisting, and ensure the smooth progress of the hoisting operation.

[0035] In this step, according to the requirements of the design drawings, the grilles and brackets required for the external platform 8 are prefabricated in advance. At the same time, other accessories such as door panels 9 and control box brackets are also made. All prefabricated parts need to be labeled and classified for storage, to be installed in the subsequent overall assembly stage. During storage, protection should be provided to avoid deformation or corrosion of the parts.

[0036] S500: TP transition section overall assembly This step involves the integrated assembly of all prefabricated components, a crucial process for achieving the overall structural forming of the TP transition section. The assembly sequence and dimensional adjustments of each component directly affect the overall structural accuracy. First, the prefabricated TP cylinder 5 is smoothly hoisted to the preset position on the transition section base plate 1 using hoisting equipment for precise assembly, ensuring that the perpendicularity and coaxiality of the TP cylinder 5 and the transition section base plate 1 meet design requirements. After assembly, internal supports are installed at preset positions inside the TP cylinder 5. These internal supports effectively prevent deformation of the TP cylinder 5 during subsequent welding and assembly processes, ensuring its structural stability.

[0037] Subsequently, according to the requirements of the design drawings, cutting operations are carried out at the preset position of TP cylinder 5. After the cutting is completed, the prefabricated door panel 9 is installed at the cutting position, and the welding and fixing of door panel 9 and TP cylinder 5 are completed. After the door panel 9 is installed, TP cylinder 5, outer platform 8 and inclined beam 3 are hoisted to the preset position in sequence and precisely assembled with TP cylinder 5 and transition section bottom plate 1. During the assembly process, the dimensions need to be measured in real time to ensure that the relative position of each component meets the design requirements.

[0038] After all components are assembled, welding is performed on each welding node. After welding is completed and passes quality inspection, all nodes at fatigue locations are ground. The grinding operation must ensure that the node surface is smooth, without sharp edges, weld beads or other defects, to effectively avoid stress concentration problems and improve the structural durability of the TP transition section. After the nodes at fatigue locations are ground, the internal support structure of the TP cylinder 5 is removed to prevent the internal support from affecting the subsequent installation of the inner platform 7.

[0039] The installation of the inner platform 7 requires the use of special assembly tooling. First, the internal support of the inner platform 7 is installed inside the TP cylinder 5 using the assembly tooling to provide an installation benchmark and support force for the inner platform 7. Then, the prefabricated and pre-treated inner platform 7 is hoisted into the TP cylinder 5. After adjusting the assembly dimensions of the inner platform 7 to ensure that its relative position with the TP cylinder 5 meets the design requirements, the inner platform 7 is fixed by applying torque with bolts. The torque of the bolts must be operated according to the design torque value to ensure the firmness of the fixation.

[0040] After the inner platform 7 is in place and fixed, the installation of various auxiliary equipment is carried out simultaneously. The dehumidification pipe, elevator accessories, electrical and instrumentation equipment, cable trays and cables are installed in sequence, and the aluminum straight ladder 13 is laid. The installation of various equipment must be carried out strictly in accordance with the position requirements of the design drawings. After the installation is completed, the position, size and flatness of the electrical and instrumentation brackets must be fully checked to ensure the installation accuracy of each electrical and instrumentation bracket and avoid collisions between electrical and instrumentation equipment, which may affect the normal operation of the equipment.

[0041] Finally, install the accessories for the outer platform 8. Following the design sequence, install the railing 14, crane 15, electrical box, and hydraulic hoses sequentially. The railing 14 must be installed at a consistent height and securely fixed. After installation, the crane 15 needs to be tested, and the hydraulic pipes should be pressure tested and oil connected to ensure the hydraulic system's sealing and normal operation. During installation, the orientation of the crane 15 boom must be strictly controlled to avoid interference with the berthing components. Then, install the ventilation pipe 16 to ensure effective ventilation within the TP transition section. During the installation of all accessories, safety stickers, backplates, safety equipment, and supporting brackets must be installed simultaneously to provide safety assurance for subsequent offshore maintenance operations.

[0042] S600: TP Transition Section Size Control Dimensional control is a core aspect throughout the entire construction process of the TP transition section. This step involves comprehensive dimensional and geometric tolerance control of the structure at each prefabrication and assembly stage to ensure that the overall accuracy of the TP transition section meets the requirements of the design drawings and relevant standards. In tolerance control, the alignment tolerance of the butt joints must strictly adhere to the following requirements: the alignment deviation of the butt joints should not exceed 0.15 times the smaller thickness of the discontinuous slab or 4 mm, whichever is smaller, to avoid excessive deviation from the butt joints affecting the load transfer efficiency of the structure.

[0043] The eccentricity of the cross joint needs to be controlled in stages according to the thickness of the continuous plate. When the thickness of the continuous plate is ≤20mm, the eccentricity is ≤2 / 2 of the continuous plate thickness and does not exceed 5mm; when the thickness of the continuous plate is >20mm, the eccentricity is ≤2 / 2 of the continuous plate thickness and does not exceed 8mm. Simultaneously, when the thickness difference between discontinuous plates of different thicknesses exceeds a specified value, the cross section of the thinner component must be completely within the cross section of the thicker component to ensure the structural stability of the cross joint. In this invention, the continuous plate refers to the plate material that runs continuously through the cross joint, and the discontinuous plate refers to the plate material that overlaps in the cross joint; the eccentricity of the cross joint is controlled in stages: when the thickness of the continuous plate is ≤20mm, the eccentricity is ≤2 / 2 of the continuous plate thickness and does not exceed 5mm; when the thickness of the continuous plate is >20mm, the eccentricity is ≤2 / 2 of the continuous plate thickness and does not exceed 8mm.

[0044] In some embodiments of this step, specific dimensional and geometric tolerance control requirements need to be formulated for the transition section base plate 1, U-shaped beam 2, inclined beam 3, side column 4, TP cylinder 5, flange and inner and outer platform 8 according to the structural characteristics and functional requirements of each component. The tolerance control work needs to be carried out throughout the entire prefabrication and final assembly cycle. Real-time dimensional measurement and deviation adjustment are required for each process from component cutting, assembly, welding to overall assembly. If the dimensional deviation is found to exceed the design requirements, work must be stopped immediately and corrective measures must be taken to ensure that the accuracy of each process meets the standards.

[0045] As a key component that connects with the wind turbine tower, the TP flange 6 has extremely high dimensional accuracy requirements. Therefore, after the flange is prefabricated, it is necessary to conduct comprehensive tolerance testing, including indicators such as outer diameter, thickness, upper surface flatness, surface roughness, bolt hole positioning, hole diameter, and edge chamfer. Each indicator must be strictly controlled according to the design requirements. Only after passing the test can it proceed to the subsequent assembly process to ensure that the flange can accurately connect with the wind turbine tower and guarantee the overall structural stability of the offshore wind power foundation.

[0046] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions within the technical scope disclosed in the present invention should be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A construction process for a steel pile-type offshore wind turbine jacket (TP) transition section, characterized in that, Includes the following steps: S100: Prefabrication of the transition section bottom plate. Steel plates are assembled and welded to form the transition section bottom plate, and a U-shaped beam is installed at the bottom of the bottom plate. After the full penetration welding of the transition section bottom plate and the U-shaped beam is completed, the transition section bottom plate is hoisted and placed on the tooling. S200: Prefabricate the inclined beams and side columns, weld the joints of the upper flange plates of the inclined beams together, then weld the upper flange plates of the inclined beams to the web plates together, and finally install and fully weld the side columns. S300: Prefabrication of TP cylinder and flange. The TP flange is hoisted into place and its dimensions are checked. Multiple cylinder sections are then butt-welded onto the TP flange one by one to form a TP cylinder structure with flange. S400: Prefabrication of inner and outer platforms and other accessories, including the layered assembly prefabrication of the inner platform and the prefabrication of the outer platform and door panels; S500: The TP transition section is assembled as a whole. The TP cylinder is assembled with the transition section bottom plate, the internal support of the TP cylinder is installed, the TP cylinder body is cut and the door panel is installed, the TP cylinder, outer platform and inclined beam are assembled, the fatigue position nodes are ground after dimensional control adjustment and welding, the internal support of the TP cylinder is removed and the inner platform and various electrical instruments and structural accessories are installed, and finally the relevant accessories of the outer platform are installed. S600: TP transition section dimensional control, which controls the dimensions and geometric tolerances of each prefabrication and assembly stage of the TP transition section to ensure that it meets the requirements of the design drawings and relevant standards.

2. The construction process of the TP transition section of the steel pile offshore wind turbine jacket according to claim 1, characterized in that, In S100, the steel plate assembly welding adopts a multiple-turning method, and the joints of different parts of the base plate are welded on both sides. The U-shaped beam and the base plate are welded on one side with full penetration.

3. The construction process of the TP transition section of the steel pile offshore wind turbine jacket as described in claim 1, characterized in that, S100 also includes the manufacturing process of the outer platform, which involves assembling and welding the steel plates of the outer platform together, installing U-shaped beams at the outer platform, and after completing the double-sided welding of the outer platform and the U-shaped beams, assembling the outer platform and the transition section bottom plate together and completing the double-sided welding.

4. The construction process of the TP transition section of the steel pile offshore wind turbine jacket according to claim 1, characterized in that, In S200, before splicing the upper flange plate of the assembly beam, lines are marked and braces are welded to control the splice size. After welding one side of the upper flange plate splice of the assembly beam, auxiliary lifting points are welded on the assembly beam. The assembly beam is then turned over using the auxiliary lifting points and the other side of the splice is welded.

5. The construction process of the TP transition section of the steel pile offshore wind turbine jacket according to claim 1, characterized in that, In the S300, after the first section of the cylinder is hoisted to the TP flange, it is first spot welded and fixed, and then it is turned over and placed on the rotating platform to complete the full welding. Subsequent sections of the cylinder are hoisted onto the rotating platform and assembled with the previous section of the cylinder. After verifying that the assembly dimensions are qualified, the full welding operation is carried out.

6. The construction process of the TP transition section of the steel pile offshore wind turbine jacket according to claim 1, characterized in that, In S400, the prefabrication of the inner platform includes the following steps: cutting steel plates and prefabricating the steel plates, railings and hinges required for the inner platform; hot-dip galvanizing all steel structures; assembling the bottom, middle and top platforms of the inner platform in sequence on the prefabrication fixtures, and installing the grilles, columns and accessories layer by layer; removing the removable grilles on the inner platform and folding the hinge beams of the inner platform.

7. The construction process of the TP transition section of the steel pile offshore wind turbine jacket according to claim 1, characterized in that, In the S500, after the TP cylinder, outer platform and inclined beam are assembled and welded, all nodes at fatigue locations are ground. After grinding, the internal support of the TP cylinder is removed.

8. The construction process of the TP transition section of the steel pile offshore wind turbine jacket according to claim 1, characterized in that, In the S500, when installing the inner platform, the internal support of the inner platform is installed using assembly tooling. After the inner platform is hoisted to the TP cylinder and the assembly dimensions are adjusted, the inner platform is fixed by applying torque with bolts. After the inner platform is in place, the dehumidification pipe, elevator accessories, electrical and instrumentation equipment, cable trays, cables and aluminum ladders are installed simultaneously, and the position, size and flatness of the electrical and instrumentation brackets are checked.

9. The construction process of the TP transition section of the steel pile offshore wind turbine jacket according to claim 1, characterized in that, In the S500, when installing external platform accessories, the railings, crane, electrical box and hydraulic hoses are installed in sequence. The hydraulic pipe pressure test and oil connection are completed. The direction of the crane arm is controlled to avoid interference with the mooring parts. Finally, the ventilation pipe is installed. At the same time, safety signs, back panels and safety equipment and supporting brackets are installed.

10. The construction process of the TP transition section of the steel pile offshore wind turbine jacket according to claim 1, characterized in that, In S600, the alignment tolerance control of butt joints follows the requirements: not exceeding 0.15 times the smaller thickness of the discontinuous plate or 4 mm, whichever is smaller; the eccentricity of cross joints is controlled according to the thickness of the continuous plate, and when the thickness difference of discontinuous plates of different thicknesses exceeds the specified value, the cross section of the thinner member is completely within the cross section of the thicker member.

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