Elevated tooling for wind turbine blade assembly and method of blade assembly

Abstract

The application discloses a heightening tool and a blade wheel assembling method for assembling a wind turbine blade wheel, wherein the heightening tool comprises a heightening base and a transition section, the transition section is used for supporting and connecting a hub, the heightening base is formed by combining three base supports of the same structure, each base support corresponds to a blade mounting hole position of the hub, each base support is provided with two symmetrical inclined corner connecting portions, each base support can be connected with each other in a head-to-tail mode through the inclined corner connecting portions to form an annular supporting structure, and the top profile of the base support is matched with the lower end surface of the transition section and used for supporting and connecting the transition section. The heightening base not only provides support for the transition section and the hub, but also further raises the hub on the basis of the transition section, thereby facilitating the hub assembling and improving the assembling efficiency; and by adjusting the connecting mode and position between the base supports, the hub and the transition section of a larger size can be adapted, the adaptability is improved, and the production cost is saved.

Description

Technical Field

[0001] This invention relates to the field of wind power generation technology, and more specifically to a heightening tooling and a method for assembling wind turbine impellers. Background Technology

[0002] Wind energy, as a new type of renewable energy, has gained increasing attention from many countries, and wind power generation technology is becoming increasingly optimized. The hub of a wind turbine is a crucial component, connecting the main shaft and blades to the turbine blades and transferring the wind load on the blades to the main shaft and gearbox. As a vital load-bearing component, the hub needs sufficient strength and rigidity, as well as good vibration damping performance, to mitigate the impact of the blade load on the main shaft. Currently, high-power wind turbine hubs are generally large. Due to height limitations during transport, hub transport bases are no longer necessary. However, this necessitates the use of a heightening fixture to secure and elevate the hub during hub cover assembly, facilitating the installation of the hub cover and other components within the hub and improving assembly efficiency.

[0003] Furthermore, due to the large size and weight of high-power wind turbine hubs, designing a hub assembly bracket that offers high support strength while maintaining advantages in terms of weight, cost, and ease of assembly and disassembly is a pressing issue. Moreover, as the wind power industry develops more and more turbine models, hub sizes are constantly changing. Using a different hub heightening fixture for each hub size would result in resource waste and increased costs. Therefore, a heightening fixture that can be used for assembling hubs of various sizes is needed. Summary of the Invention

[0004] The summary section introduces a series of simplified concepts, which will be further explained in detail in the detailed description section. The summary section of this invention is not intended to limit the key features and essential technical features of the claimed technical solution, nor is it intended to determine the scope of protection of the claimed technical solution.

[0005] To at least partially solve the above problems, the present invention provides a heightening fixture for assembling wind turbine rotors, including a heightening base and a transition section. The transition section is constructed as a ring structure with its upper end face matching the main shaft side end face of the hub, used to support the hub and connected to it by bolts. The heightening base is formed by combining three identical base brackets, the positions of each base bracket corresponding to the blade mounting holes of the hub. The base bracket is constructed as a roughly cuboid outline structure with two symmetrically arranged inclined corner connecting parts. The three base brackets can be connected end to end to form a ring support structure through their respective inclined corner connecting parts. The top outline of the heightening base matches the lower end face of the transition section, used to support the transition section and connected to it by bolts.

[0006] Furthermore, the base support includes a frame structure formed by welding angle steel, two side plates made of channel steel, and two connecting plates made of steel plates. The side plates and the connecting plates are respectively welded to the frame structure, and the connecting plates are provided with bolt holes for interconnection between the base supports.

[0007] Furthermore, the heightening fixture also includes three identical extended supports. Each extended support includes two steel beams and at least one crossbeam that are detachably connected to the two side plates of the base support. The steel beams extend radially along the transition section, and the two ends of the crossbeam are respectively connected to the two steel beams.

[0008] Furthermore, the side plate is provided with a strip steel plate and bolt holes located on the upper and lower sides of the strip steel plate. The steel beam is provided with two steel plates with bolt holes at the end where it is connected to the side plate. The two steel plates are spaced apart along the height direction by a distance matching that of the strip steel plate, so that the extended bracket and the base bracket are connected to each other by bolts and keyway structure.

[0009] Furthermore, the base support also includes a platform plate disposed on the top of the frame structure. The platform plate is bolted to the longitudinal angle steel and two transverse angle steels at the upper inner side of the frame structure, so that the platform plate is located inside the transition section.

[0010] Furthermore, the transition section includes an upper ring plate for bolting to the hub, a lower ring plate for bolting to the heightened base, a cylindrical body with its upper and lower ends welded to the upper ring plate and the lower ring plate respectively, and a plurality of web plates evenly distributed along the circumference. The upper side, lower side, and inner side of the web plates are welded to the lower end face of the upper ring plate, the upper end face of the lower ring plate, and the outer side of the cylindrical body respectively.

[0011] Furthermore, the lower ring plate includes three first segments with straight outer sides and three second segments with arc-shaped outer sides, the first segments and the second segments being alternately arranged such that the outer sides of the three first segments are respectively flush with the outer sides of the three base supports.

[0012] Furthermore, the lower ring plate is provided with outer bolt holes and inner bolt holes located on the outer and inner sides of the cylindrical body, respectively. Both the outer bolt holes and the inner bolt holes are elongated oval bolt holes that extend along the length of the angle steel to which they are connected.

[0013] The present invention also provides an impeller assembly method using the above-mentioned height-enhancing tooling, comprising the following steps:

[0014] S1: Arrange the three base supports symmetrically at their centers to form a raised base;

[0015] S2: Connect the transition section to the raised base using bolts;

[0016] S3: Connect the hub to the transition section with bolts so that the three blade mounting holes of the hub correspond to the three base brackets respectively;

[0017] S4: Assemble the components inside the wheel hub and the wheel hub cover.

[0018] Furthermore, the above impeller assembly method also includes the following steps:

[0019] S5: Transport the assembled wheel hubs to the wind farm;

[0020] S6: Connect the heightening base, transition section and extension support in the wind farm to form a heightening fixture;

[0021] S7: Install the assembled wheel hubs onto the transition section;

[0022] S8: Lift the three blades and install them onto the hub;

[0023] S9: Disassemble the heightening fixture and hoist the assembled impeller as a whole.

[0024] The heightening fixture of this invention comprises two parts: a heightening base and a transition section. The heightening base provides support for the transition section and wheel hub above it, and also, due to its own height, further elevates the wheel hub based on the transition section, facilitating wheel hub assembly and improving assembly efficiency. The heightening base is formed by three identical base supports connected by bolts, which facilitates production and processing, and is convenient for transportation and on-site assembly due to its easy disassembly and assembly. By adjusting the connection method and position between the base supports, it can accommodate larger wheel hubs and transition sections, improving adaptability and saving production costs. Attached Figure Description

[0025] The following figures are included as part of this invention for understanding its principles. The figures illustrate embodiments of the invention and their descriptions, serving to explain the apparatus and principles of the invention. In the figures,

[0026] Figure 1 This is a three-dimensional structural diagram of the heightened tooling according to an embodiment of the present invention;

[0027] Figure 2 This is a three-dimensional structural diagram of the heightened base according to an embodiment of the present invention;

[0028] Figure 3 This is a three-dimensional structural diagram of the transition section according to an embodiment of the present invention;

[0029] Figure 4 This is a three-dimensional structural diagram of the base support according to an embodiment of the present invention;

[0030] Figure 5 A three-dimensional structural diagram of a heightened tooling with an extended support frame;

[0031] Figure 6 This is a three-dimensional structural diagram of the extended support according to an embodiment of the present invention;

[0032] Figure 7 This is a three-dimensional structural diagram of the platform board according to an embodiment of the present invention;

[0033] Figure 8 This is a three-dimensional structural diagram of the connecting plate according to an embodiment of the present invention.

[0034] The markings in the attached diagram are as follows:

[0035] 1. Raised base; 11. Base support; 111. Frame structure; 1111. Longitudinal angle steel; 1112. Longitudinal angle steel; 1113. Horizontal angle steel; 1114. Vertical angle steel; 1115. Diagonal angle steel; 112. Side plate; 113. Connecting plate; 1131. Bolt hole; 1132. Bolt hole; 1133. Bolt hole; 114. Platform plate; 1141. Bolt hole; 1142. Bolt hole;

[0036] 2. Transition section; 21. Upper ring plate; 211. Long oval bolt hole; 22. Lower ring plate; 221. First part; 222. Second part; 223. Outer bolt hole; 224. Inner bolt hole; 23. Cylindrical body; 24. Web plate;

[0037] 3. Extended support; 31. Steel beam; 311. Steel plate; 3111. Bolt hole; 312. Bolt hole; 32. Crossbeam; 321. Steel plate; 3211. Bolt hole. Detailed Implementation

[0038] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. The described embodiments are merely preferred embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0039] It should be understood that, unless otherwise defined, the technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention. Terms such as “part” and “component” appearing herein may refer to a single part or a combination of multiple parts. The singular forms “a,” “an,” and “the” are also intended to include the plural forms unless the context clearly indicates otherwise. Ordinal numbers such as “first” and “second” are merely identifiers and have no other meaning, such as a specific order. Moreover, for example, the term “first component” does not imply the existence of a “second component,” and the term “second component” does not imply the existence of a “first component.” When the terms “comprising” and / or “including” are used in this specification, they indicate the presence of the stated feature, integral, step, operation, element, and / or component, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components, and / or combinations thereof. The terms “upper,” “lower,” “front,” “rear,” “left,” “right,” “inner,” “outer,” “center,” “vertical,” “horizontal,” and similar expressions are for illustrative purposes only and are not limiting. The terms "connection," "installation," "linking," and "setting" should be interpreted broadly. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art will understand the specific meaning of these terms in this invention based on the specific circumstances. Features described in one embodiment may be applied alone or in combination with other features in another embodiment, unless that feature is not applicable in that other embodiment or is otherwise specified.

[0040] Hereinafter, specific embodiments of the present invention will be described in more detail with reference to the accompanying drawings, which illustrate representative embodiments of the present invention and are not intended to limit the present invention.

[0041] This invention provides a heightening fixture for assembling wind turbine impellers. For example... Figure 1-8As shown, the heightening fixture includes a heightening base 1 and a transition section 2. The transition section 2 is a ring structure with its upper end face matching the spindle side end face of the hub, used to support the hub and connected to it with bolts. The heightening base 1 is formed by combining three identical base supports 11, the positions of which correspond to the blade mounting holes of the hub. The base supports 11 are generally rectangular parallelepiped structures with inclined corner connections. The three base supports 11 can be connected end to end to form a ring support structure through their respective inclined corner connections. The top profile of the heightening base 1 matches the lower end face of the transition section 2, used to support the transition section 2 and connected to it with bolts. The raised base 1 provides support for the transition section 2 and the wheel hub above it. Its height also elevates the wheel hub beyond the transition section 2, facilitating wheel hub installation and improving installation efficiency. The raised base 1 can be formed by three identical base supports 11 connected by bolts through their respective inclined corner joints, simplifying manufacturing and facilitating transportation and on-site assembly due to its ease of disassembly and assembly. Furthermore, when a larger wheel hub needs to be installed, the original three base supports 11 can be used in conjunction with the enlarged transition section. Specifically, the three base supports 11 can be arranged radially outward along the transition section and connected to the enlarged transition section by bolts. The three base supports 11 are spaced apart from each other and not connected to one another.

[0042] According to embodiments of the present invention, such as Figure 4As shown, the base support 11 includes a frame structure 111 formed by welding angle steel, two side plates 112 made of channel steel, and two connecting plates 113 made of steel plates. The side plates 112 and connecting plates 113 are welded to the frame structure 111. Specifically, the frame structure 111 uses a total of five specifications of angle steel, including two longitudinal angle steels 1111 located at the upper and lower ends of the inner side, two longitudinal angle steels 1112 located at the upper and lower ends of the outer side, four transverse angle steels 1113 welded to the longitudinal angle steels 1111 and 1112 at both ends, six vertical angle steels 1114, and four oblique angle steels 1115. Among them, the two ends of the oblique angle steels 1115 are welded to the side plates 112 and the longitudinal angle steels 1111 on the inner side of the frame structure, and the outer surface of the oblique angle steels 1115 is welded to the connecting plates 113 to form the aforementioned inclined corner connection. The main structure of the base bracket 11 adopts a frame structure welded from angle steel, with channel steel and connecting steel plates on both sides, which can minimize weight and save materials while ensuring support strength. The angle between the two connecting plates 113 of the base bracket 11 and the inner end face of the frame structure 111 is set to 150°, that is, the inclination angle of the inclined corner connection relative to the inner side of the base bracket 11 is set to 30°, so that the three base brackets 11, after being connected to each other through their respective connecting plates 113, form a support structure with an equilateral triangle inner cross-section, where each base bracket 11 supports one-third of the transition section 2; the length and width of the base bracket 11 are set to be approximately equal to the maximum dimensions of its upper one-third transition section along the chord length and radial direction, thereby providing sufficient support strength. Figure 4 and Figure 6 As shown, the connecting plate 113 has three sets of bolt holes 1131, 1132, and 1133 (upper, middle, and lower). Correspondingly, the upper and lower inclined angle steels 1115 have bolt holes that match the upper and lower sets of bolt holes 1131 and 1133 of the connecting plate 113. During the processing of the base bracket 11, the upper and lower sets of bolt holes 1131 and 1133 of the connecting plate 113 are aligned with the bolt holes of the upper and lower inclined angle steels 1113, and then the connecting plate 113 is welded to the upper and lower inclined angle steels 1113 along its edge. During the assembly of the base 1, the connecting plates of each base bracket 11 are butted together and bolted together through the three sets of bolt holes 1131, 1132, and 1133. Based on the bolted connection of the three base brackets 11 to the upper transition section 2, the bolted connection between the base brackets 11 to form a centrally symmetrical structure can improve the support strength, which is especially necessary when assembling the hub and blades in the wind farm before the overall hoisting of the impeller.

[0043] like Figure 5 and Figure 6As shown, the heightening fixture of the present invention may further include three extended supports 3 with the same structure. Each extended support 3 includes two steel beams 31 and at least one crossbeam 32 that are detachably connected to the two side plates 112 of the base support 11. The steel beams 31 extend radially along the transition section 2, and the two ends of the crossbeam 32 are connected to the two steel beams 31 respectively. Channel steel can be used as the main structure of the steel beams 31 and the crossbeam 32. To strengthen the connection between the base support 11 and the extended supports 3, such as... Figure 4 and Figure 6 As shown, the side plate 112 of the base support 11 is provided with a strip steel plate 1121 and bolt holes 1122 located on the upper and lower sides of the strip steel plate 1121. The steel beam 31 has two steel plates 311 with bolt holes 3111 welded to one end of its connection with the side plate 112. The two steel plates 311 are spaced apart along the height direction at a distance matching that of the strip steel plate 1121, so that the extended support 3 and the base support 11 are connected to each other by bolts and keyway structure. The other end of the steel beam 31 is provided with bolt holes 312. Correspondingly, the two ends of the crossbeam 32 are respectively welded with steel plates 321 with bolt holes 3211, so as to be connected to the two steel beams 31 by bolts respectively. The extended bracket 3 is suitable for on-site installation of the turbine unit using the overall impeller hoisting method. Before the overall impeller hoisting, the heightening fixture and hub need to be set up on the wind farm ground. Then, the three blades are hoisted and installed onto the hub. Since there may be a large overturning moment during the blade installation process, the heightening fixture connected to the bottom of the hub is extended with an extended bracket 3 that extends along the blade length direction. The extended bracket 3 is connected to the base bracket 11 by bolts and keyway structure, which can effectively improve the safety and reliability of the on-site installation process of the turbine unit.

[0044] According to an embodiment of the present invention, the base support 11 further includes a platform plate 114 disposed on top of the frame structure 111. The platform plate 114 is bolted to the longitudinal angle steel 1111 and two transverse angle steels 1112 located at the upper inner side of the frame structure 111, so that the platform plate 114 is entirely located inside the transition section 2. During wheel hub assembly, the operator can stand stably on the platform plate to install the internal components of the wheel hub, thereby improving assembly efficiency and operational safety. The three platform plates 114 can be respectively located at the positions of the three blade mounting holes of the wheel hub to facilitate the operator's corresponding installation operations.

[0045] According to an embodiment of the present invention, the transition section 2 includes an upper ring plate 21 for bolting to the wheel hub, a lower ring plate 22 for bolting to the raised base 1, a cylindrical body 23 welded to the upper ring plate 21 and the lower ring plate 22 at its upper and lower ends respectively, and a plurality of web plates 24 evenly distributed circumferentially. Figure 1 and Figure 3As shown, the lower ring plate 22 includes three first segments 221 with straight outer edges and three second segments 222 with arc-shaped outer edges. The first segments 221 and second segments 222 are alternately arranged, such that the outer edges of the three first segments 221 are flush with the outer edges of the three base supports 11. In order to provide stable and reliable support, it is necessary to maximize the area of ​​the lower ring plate 22 and the corresponding load-bearing area of ​​the base supports 11. The above-mentioned arrangement of the lower ring plate 22 can increase the contact area with the base supports 11, reduce the weight and floor space, and leave an inner area for installing the platform plate 114. Furthermore, the central positions of each second segment 222 of the lower ring plate 22 press against the inclined corner connection of the two base supports 11. Correspondingly, in order to strengthen the support strength at this position, the outer end of the inclined angle steel 1115 is welded to the side plate 112 formed by the channel steel, and the inner end is welded to the longitudinal angle steel 1111 and an additional vertical angle steel 1114 is added (four of the six vertical angle steels 1114 are located inside the base support 11). In addition, the connecting plate 113 is used for the interconnection between the base supports 11. Since its upper and lower ends are welded to the upper and lower inclined angle steels 1115 respectively and bolted, it can further improve the support strength at the inclined corner connection.

[0046] like Figure 1 and Figure 3 As shown, the upper end of the cylindrical body 23 is welded to the inner edge of the upper ring plate 21 or near the inner edge. Correspondingly, the upper, lower, and inner edges of the web plate 24 are welded to the lower end face of the upper ring plate 21, the upper end face of the lower ring plate 22, and the outer surface of the cylindrical body 23, respectively, to enhance the support strength of the transition section 2. Preferably, the upper ring plate 21 is provided with elongated bolt holes 211 that are evenly distributed circumferentially and extend radially, thereby increasing the range of wheel hub sizes that can be used and improving adaptability. The lower ring plate 22 includes a wider portion located outside the cylindrical body 23 and a narrower portion located inside the cylindrical body 23. The two portions are respectively provided with outer bolt holes 223 and inner bolt holes 224. Both the outer bolt holes 223 and the inner bolt holes 224 are elongated bolt holes that extend along the length of the angle steel to which they are connected, in order to avoid connection difficulties due to processing or installation errors and improve installation efficiency. The wider section has multiple aligned elongated bolt holes near each straight segment for bolt connection to the longitudinal angle steel 1112 at the upper outer side of the frame structure 111. Additionally, as... Figure 4 and Figure 5As shown, the longitudinal angle steel 1111 and the transverse angle steel 1113 at the upper inner side of the frame structure 111 are each provided with bolt holes for connecting with the lower ring plate 22 and the platform plate 114 respectively; correspondingly, the platform plate 114 is provided with at least two bolt holes 1141 for connecting with the longitudinal angle steel 1111, which are aligned laterally and spaced apart longitudinally, and at least two bolt holes 1142 for connecting with the transverse angle steel 1113, which are aligned longitudinally and spaced apart laterally.

[0047] The present invention also provides an impeller assembly method using the above-mentioned height-enhancing tooling, comprising the following steps:

[0048] S1: Arrange the three base supports 11 symmetrically at the center to form the raised base 1;

[0049] S2: Connect the transition section 2 to the raised base 1 using bolts;

[0050] S3: Connect the hub to the transition section 2 with bolts so that the three blade mounting holes of the hub correspond to the three base brackets 11 respectively;

[0051] S4: Assemble the components inside the wheel hub and the wheel hub cover.

[0052] After completing the above steps at the factory, if it is necessary to hoist the rotor as a whole at the wind farm, the following steps can be continued:

[0053] S5: Transport the assembled wheel hubs to the wind farm;

[0054] S6: Connect the heightening base 1, transition section 2 and extension bracket 3 in the wind farm to form a heightening fixture;

[0055] S7: Install the assembled wheel hubs onto transition section 2;

[0056] S8: Lift the three blades and install them onto the hub;

[0057] S9: Disassemble the heightening fixture and hoist the assembled impeller as a whole.

[0058] The present invention has been described through the above embodiments. However, it should be understood that the above embodiments are for illustrative purposes only and are not intended to limit the present invention to the described embodiments. Furthermore, those skilled in the art will understand that the present invention is not limited to the above embodiments, and many variations and modifications can be made based on the teachings of the present invention, all of which fall within the scope of protection claimed by the present invention. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. An elevation tooling for wind turbine blade wheel assembly, characterized by, The system includes a raised base (1) and a transition section (2). The transition section (2) is a ring structure whose upper end face matches the main shaft side end face of the hub. It is used to support the hub and is connected to the hub by bolts. The raised base (1) is formed by combining three base brackets (11) with the same structure. The position of each base bracket (11) corresponds to the position of the blade mounting hole of the hub. The base bracket (11) is a roughly cuboid outline structure with two symmetrically arranged inclined corner connecting parts. The three base brackets (11) can be connected by their respective inclined corner connecting parts and bolted together. The upper ring base (1) is connected to form a ring support structure. The top profile of the raised base (1) matches the lower end face of the transition section (2) to support the transition section (2) and is connected to the transition section (2) by bolts. The transition section (2) includes an upper ring plate (21) for bolt connection to the hub, a lower ring plate (22) for bolt connection to the raised base (1), and a cylindrical body (23) welded to the upper ring plate (21) and the lower ring plate (22) at its upper and lower ends respectively. The upper ring plate (21) is provided with elongated bolt holes (211) that are evenly distributed in the circumference and extend in the radial direction.

2. The raising tooling of claim 1, wherein, The base support (11) includes a frame structure (111) formed by welding angle steel, two side plates (112) made of channel steel and two connecting plates (113) made of steel plate. The side plates (112) and the connecting plates (113) are respectively welded to the frame structure (111). The connecting plates (113) are provided with bolt holes (1131, 1132, 1133) for connecting the base supports (11) to each other.

3. The raising tooling of claim 2, wherein, It also includes three identical extended supports (3), each extended support (3) comprising two steel beams (31) detachably connected to the two side plates (112) of the base support (11) and at least one crossbeam (32), the steel beams (31) extending radially along the transition section (2), and the two ends of the crossbeam (32) being connected to the two steel beams (31) respectively.

4. The raising tooling of claim 3, wherein, The side plate (112) is provided with a strip steel plate (1121) and bolt holes (1122) located on the upper and lower sides of the strip steel plate (1121). The steel beam (31) is provided with two steel plates (311) with bolt holes (3111) at one end connected to the side plate (112). The two steel plates (311) are spaced apart along the height direction at a distance matching that of the strip steel plate (1121), so that the extended bracket (3) and the base bracket (11) are connected to each other by bolts and keyway structure.

5. The raising tool of claim 2, wherein The base support (11) also includes a platform plate (114) disposed on the top of the frame structure (111) and located entirely inside the transition section (2).

6. The height-increasing tooling according to claim 1, characterized in that, The transition section (2) also includes a plurality of web plates (24) evenly distributed along the circumference. The upper side, lower side and inner side of the web plates (24) are welded to the lower end face of the upper ring plate (21), the upper end face of the lower ring plate (22) and the outer side of the cylindrical body (23), respectively.

7. The height-increasing tooling according to claim 1, characterized in that, The lower ring plate (22) includes three first sections (221) with straight outer sides and three second sections (222) with arc-shaped outer sides. The first sections (221) and the second sections (222) are alternately arranged so that the outer sides of the three first sections (221) are flush with the outer sides of the three base supports (11).

8. The height-increasing tooling according to any one of claims 1-7, characterized in that, The lower ring plate (22) is provided with an outer bolt hole (223) and an inner bolt hole (224) located on the outer and inner sides of the cylindrical body (23), respectively. Both the outer bolt hole (223) and the inner bolt hole (224) are elongated oval bolt holes that extend along the length of the angle steel of the frame structure (111) connected to it.

9. A method for assembling an impeller, using the height-enhancing tooling described in any one of claims 1-8, characterized in that, The steps include the following: S1: Arrange the three base supports (11) symmetrically at the center to form a raised base (1); S2: Connect the transition section (2) to the raised base (1) with bolts; S3: Connect the hub to the transition section (2) with bolts so that the three blade mounting holes of the hub correspond to the three base brackets (11) respectively; S4: Assemble the components inside the wheel hub and the wheel hub cover.

10. The impeller assembly method according to claim 9, characterized in that, It also includes the following steps: S5: Transport the assembled wheel hubs to the wind farm; S6: Connect the heightening base (1), transition section (2) and extension bracket (3) in the wind farm to form the heightening fixture as described in claim 3 or 4; S7: Install the assembled wheel hub into the transition section (2); S8: Lift the three blades and install them onto the hub; S9: Disassemble the heightening fixture and hoist the assembled impeller as a whole.

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