Transport device

Abstract

This invention describes a handling device (1) for handling a wind turbine rotor blade (20), the handling device comprising: a frame assembly (11) configured to be assembled around an airfoil portion (20A) of the rotor blade (20); a plurality of attachment covers (10) arranged to be assembled between the frame assembly (11) and the airfoil surface, wherein the attachment covers (10) are shaped to be assembled around a plurality of attachments (200); and a load-bearing material (M) for filling the attachment covers (10) when the attachment covers (10) are pressed against the rotor blade (20). This invention also describes a method for handling a wind turbine rotor blade (20).

Description

Background Technology

[0001] Wind turbine rotor blades can be equipped with functional add-ons to improve their aerodynamic performance, reduce noise, and so on. These add-ons can be relatively small protrusions attached to the surface of the rotor blades to interact with the airflow. One example of an add-on is a vortex generator designed as a small vane to delay stall.

[0002] Attachments can significantly improve the performance of wind turbine rotor blades, but they increase complexity during handling and installation. For example, handling tools such as clamps cannot be placed directly on the attachments to avoid damaging them. However, attachments are often placed in locations that are preferred contact areas for handling tools such as lifting accessories; for example, a favorable location for a set of vortex generators might be along the line of the thickest part of the airfoil. This line of maximum thickness typically coincides with the outer end of the structural web inside the rotor blade, and therefore, is a preferred location for placing handling tools such as lifting accessories. This is problematic, especially when the attachment is located near the center of mass of the rotor blade.

[0003] To avoid contact between the eddy current generator and any part of the transport equipment, the simplest option is to keep any contact area free of additional devices. However, even omitting only a few such additional devices comes at the cost of suboptimal aerodynamic performance. Alternatively, the rotor blades can be transported to avoid contact between any transport equipment and additional devices. For example, when lifting the rotor blades to the hub of a wind turbine during installation, the blades can be held in a vertical orientation with their root end facing upwards and their tip downwards. One disadvantage of this method is that the rotor blades must first be rotated from a horizontal orientation (the usual orientation during transport) to a vertical position, and such manipulation is difficult and dangerous.

[0004] In another approach, the rotor blades can be held horizontally with their leading edge pointing downwards and their trailing edge upwards. In this orientation, the weight of the rotor blades can be transferred vertically to the conveying device via their leading edge. However, the wind load on the upright, windward surface of the rotor blades can be very high, and the resulting deflection and oscillations can severely hinder the installation process and may significantly increase the risk of personnel injury and equipment damage.

[0005] For these reasons, it may be preferable to keep the rotor blades horizontally oriented, with their leading and trailing edges forming a horizontal plane, for example, where the leading edge faces the upwind direction. However, this requires the handling equipment to be configured to avoid any contact with additional devices on the outer surface of the rotor blades. If these additional devices are arranged in a typical configuration, i.e., close to the structural web, the handling equipment may need to clamp the rotor blades in a suboptimal position, i.e., in front of or behind the line of maximum thickness. Alternatively, one or more sets of additional devices may be “sacrificed” to make room for the padding of the handling equipment. However, this comes at the cost of aerodynamic performance.

[0006] Therefore, one object of the present invention is to provide a method for handling rotor blades that avoids damage to any additional devices on their outer surface.

[0007] This objective is achieved by the claimed handling device and the claimed method of handling wind turbine rotor blades. Summary of the Invention

[0008] In the context of this invention, it should be understood that wind turbine rotor blades are equipped with functional attachments protruding from the surface of the rotor blade, commonly referred to as auxiliary devices. For example, a row of triangular guide vanes may be arranged parallel to the leading edge on the suction side of the rotor blade. This row of auxiliary devices may begin near the shoulder or transition between the airfoil and the root end, and may extend along a portion of the length of the rotor blade. Of course, there are many reasons for providing such auxiliary devices and many possible locations. Hereinafter, it is assumed that the auxiliary devices are located in areas of the rotor blade that are relevant during handling processes such as lifting or rotation.

[0009] According to the present invention, the handling arrangement includes: a frame assembly configured to assemble around an airfoil portion of a rotor blade; a plurality of add-on covers arranged to be fitted between the frame assembly and the airfoil surface, wherein the add-on covers are shaped to assemble around the plurality of add-ons; and a load-bearing material for filling the add-on covers when they are pressed against the rotor blade. The load-bearing material of the handling arrangement of the present invention should be understood to include substantially incompressible materials, i.e., materials whose volume remains substantially constant under pressure. The substantially incompressible material should be understood to include particulate materials and / or non-solid materials, such as liquids or gels. The load-bearing material may comprise a single substance or a combination of substances.

[0010] One advantage of the handling device of the present invention is that it helps protect the attachments without adding any complexity to handling and / or lifting operations. The attachment cover can be shaped to assemble around several of a series of existing attachments. A load-bearing material fills the attachment cover such that its interior is substantially filled with that material. During handling, the weight of the rotor blades is transferred from the load-bearing material to the attachment cover and from there to the frame assembly. When no longer needed, the attachment cover can be simply removed, allowing the load-bearing material to be dispersed.

[0011] According to the present invention, a method for handling wind turbine rotor blades includes an initial step of arranging the rotor blades in a substantially horizontal orientation, i.e., it should be understood that the rotor blades are arranged such that their airfoil plane is substantially horizontal. The method further includes the steps of: arranging a frame assembly of the handling device of the present invention around the airfoil of the rotor blades; arranging an attachment cover of the handling device around a plurality of attachments; pressing the attachment cover against the rotor blades; and filling the attachment cover of the handling device with substantially incompressible load-bearing material. These steps can be performed in any suitable order; for example, the attachment cover may be filled with load-bearing material before or after it is pressed against the rotor blades.

[0012] Particularly advantageous embodiments and features of the invention are given by way of the dependent claims, as disclosed in the following description. Features from different categories of claims may be combined, as appropriate, to provide further embodiments not described herein.

[0013] It can be assumed that the frame assembly includes some holding or clamping devices that are assembled around the airfoil and operable to securely hold the rotor blades during handling. For example, the frame assembly can be implemented as a remotely operable hydraulic or motorized clamping mechanism. It can be assumed that the handling device is implemented for lifting by a crane, such as a crane equipped on an installation vessel assembling an offshore wind turbine.

[0014] In the following text, it can be assumed that the rotor blades are kept horizontally oriented with the suction side facing down during transport. This orientation has the advantage that lift is maintained to a manageable minimum as the rotor blades are being lifted into position at hub height. The disadvantage of this orientation is that additional devices are generally mounted at least on the suction side, typically in the area along a line coinciding with the thickest part of the airfoil, which is also the preferred location for the liner of the positioning transport equipment. Additional devices can also be present on the pressure side, for example, in cases where the rotor blades are configured with an airfoil having a high relative thickness. Such a "thick" airfoil is prone to stall and benefits from additional devices on the pressure side, such as a row of vortex generators arranged along the first 30% or so of the rotor blade length.

[0015] As explained above, the web inside the rotor blade typically extends along the widest transverse of the airfoil, and the liner of the handling device is preferably placed on either side of the web for optimal load transfer. Therefore, when the attachment is present in this preferred liner location, conventional handling tools cannot be used to lift such a rotor blade to its "inverted airfoil" position. As explained herein, the present invention provides a solution to this problem.

[0016] The terms “additional device cover,” “additional device protector,” “protective cover,” “protective cup,” or simply “cup” or “cover” are considered synonyms in the context of this invention and may be used interchangeably herein.

[0017] The substantially incompressible load-bearing material (hereinafter referred to as "filler") includes any of the following: any microparticles such as sand, gels such as water-based gels, colloids such as sand / water mixtures, and liquids such as fresh water or seawater. The filler may include any combination of the above materials. In the case of gels or colloids, the filler is preferably water-soluble. The filler is also preferably not significantly adhered to surfaces, so that it can be easily removed from the interior of the cup or from the surfaces of the airfoils and attachments. The selected filler is preferably environmentally safe, such that it disperses and / or degrades without posing any risk to the environment.

[0018] The attachment cover can have any suitable shape and can be made of any suitable material. In a preferred embodiment of the invention, the attachment cover is made of a rigid housing that can be attached or mounted to a frame assembly. For example, the attachment cover can be shaped as an elliptical, circular, or regular container or box with a substantially flat base, or as a bowl or plate with a circular base. This base can be adapted to be bolted, welded, or otherwise attached to a suitable part of the frame assembly. The attachment cover can replace the liner of conventional handling equipment, eliminating the need to construct entirely new handling equipment. The attachment cover serves substantially the same purpose as the liner and can be referred to in the context of the liner below.

[0019] The depth of the protective cup is preferably slightly greater than the height of the attachment. For example, if the attachment to be protected is 3 cm in height, the protective cup preferably has a depth of about 4 cm.

[0020] To accommodate the filler during lifting / handling operations, the protective cup preferably includes a seal extending around the upper edge of the housing. For example, such a seal can be implemented as an inflatable chamber or hose. Alternatively, the seal can be implemented as a flexible lip made of rubber or some other material. Similarly, the seal can be implemented as a gasket. The seal is preferably configured to accommodate the filler within the cap during handling. In a particularly preferred embodiment of the invention, the seal is shaped to bend inwards such that when the protective cap is pressed against the rotor blade surface, the subsequent pressure on the filler material acts to press the seal against the rotor blade, resulting in the filler material always being reliably contained within the cap.

[0021] The protective cup can be shaped to conform to the curvature of the airfoil. Alternatively or additionally, the conformation to the airfoil profile can be achieved by using a seal of appropriate size, thereby effectively preventing the filler from passing between the seal and the airfoil surface.

[0022] As shown above, the carrier material can be filled into the protective cover before it is pressed against the surface of the rotor blades. Alternatively, it may be preferable to first arrange the cover relative to a set of attachments, and then press the cover against the airfoil surface, and finally fill it with the selected carrier material. For this purpose, the attachment cover preferably includes a port for conveying the selected filler into the cavity when the cover is in place against the rotor blades. In this way, the cavity can be optimally filled with carrier material. The inlet port is particularly advantageous when the selected filler is a liquid, particulate, or a combination thereof (e.g., sand and water).

[0023] After the rotor blades have been installed into the hub, the conveying equipment is separated, for example, by remotely controlling the frame assembly to release the airfoil. The packing material can now escape from the attachment cover. There is no need to collect the packing material: in the case of water, it will simply flow away from the rotor blades; in the case of wet or dry sand, it will simply fall off the rotor blades; gels or colloids may slip off the rotor blades or may be dissolved by rainwater.

[0024] When the frame assembly is released after the horizontally oriented rotor blades have been attached to the hub, some lateral displacement may occur between the frame assembly and the rotor blades. This could be due to imperfect alignment of the crane's and handling equipment's centers of mass, wind loads, or other reasons. A significant advantage of this invention is that any such lateral displacement of the frame assembly and its attachment cover when the frame assembly is released from the rotor blades will not result in undesirable lateral forces on the attachment, because the particulate, liquid, or colloidal filler (still within the cup) is physically unable to bear or transmit substantial shear loads, especially when the cover is no longer pressed against the rotor blades.

[0025] The handling device of the present invention can be used at any stage of handling finished rotor blades. Preferably, the step of arranging the frame assembly around the airfoil is performed after the final manufacturing stage of the rotor blade, for example, after the final polishing step, at which point the rotor blade is ready to be transported to its final destination. Preferably, any additional device covers of the handling device are released after the rotor blade is installed, i.e., after the root end of the rotor blade has been attached to the hub of the wind turbine. This method is particularly suitable for handling equipment that is intended to remain in place during all transport and handling stages. In this way, vulnerable additional devices on the rotor blade surface are protected during all handling stages.

[0026] The frame assembly may be equipped with multiple additional pads arranged to be positioned against the surface of the rotor blades to aid in load stability during lifting. For example, stabilizing pads may be positioned on either side of an attachment cover above an attachment placed on the underside of the rotor blades. In this embodiment, the stabilizing pads may be further positioned towards the leading edge and / or further towards the trailing edge. During lifting, the weight of the rotor blades is primarily transferred to the transport frame through the housing of the attachment cover, and the stabilizing pads help bear, i.e., transfer, the horizontal load. Similarly, stabilizing pads may be positioned where the pressure side faces upwards during lifting and where there is no attachment along the region of maximum thickness. Attached Figure Description

[0027] Other objects and features of the invention will become apparent from the following detailed description taken in conjunction with the accompanying drawings. However, it is to be understood that the drawings are for illustrative purposes only and are not intended to limit the scope of the invention.

[0028] Figure 1 The illustration shows one stage of the method for handling wind turbine rotor blades according to the present invention;

[0029] Figure 2 and Figure 3 An exemplary wind turbine rotor blade is shown;

[0030] Figure 4 An embodiment of the handling device of the present invention is shown during the handling, transporting, or lifting phase;

[0031] Figure 5-8 Details of an exemplary embodiment of the conveying device of the present invention are shown.

[0032] In the accompanying drawings, the same reference numerals denote the same objects throughout. The objects in the drawings are not necessarily drawn to scale. Detailed Implementation

[0033] Figure 1The image shows a wind turbine rotor blade 20 during the installation process. The rotor blade 20 is being lifted to the level of the hub 21 of the offshore wind turbine, so that its root end 20R can be attached to the hub 21. As shown, a transport device 1 holds the rotor blade 20, i.e., its airfoil portion 20A is in a substantially horizontal orientation, and this transport device 1 is lifted by a crane (shown only partially), such as a crane on the installation vessel in the case of an offshore wind turbine.

[0034] Each rotor blade 20 of the wind turbine 2 has an arrangement of additional devices 200 on its suction side 20S, such as Figure 2 As shown in the exemplary embodiment, the auxiliary device 200 for the vortex generator is arranged substantially parallel to the leading edge LE in this case and is used to improve the aerodynamic performance of the rotor blade 20. Of course, the rotor blade may be equipped with other additional auxiliary devices in various arrangements, and additional devices may also be present on its pressure side.

[0035] During the lifting process, the rotor blades can preferably be held with their suction side 20S facing downwards. This is to avoid unfavorable large lift caused by the airflow above the rotor blades 20, as those skilled in the art will know, especially when the leading edge LE faces the wind. However, as Figure 3 As shown, the advantageous position for the auxiliary device 200 is aligned with the structurally reinforced web 20W arranged inside the rotor blades. Therefore, this position is also the most suitable for placing the liner for the conveying device. Conventionally, the solution is to omit a sufficient number of auxiliary devices to allow clearance for the lifting equipment liner (with a associated reduction in aerodynamic efficiency), or to construct a liner for placement on one or both sides of the auxiliary device (thus risking damage to the rotor blades).

[0036] The conveying device 1 of the present invention is configured to grip the rotor blades 20 without damaging any additional devices 200. This is in Figure 4 The diagram in the middle shows, Figure 4A conveying device 1 is shown positioned around a rotor blade 20, which is oriented such that its suction side 20S faces downward. In this exemplary embodiment, the conveying device 1 includes a frame assembly 11 configured to assemble around an airfoil portion 20A of the rotor blade 20 and to clamp the rotor blade 20 between gaskets 10, 11P in a region near the center of mass of the rotor blade 20. Here, gaskets 10, 11P are substantially aligned with a structurally reinforcing web 20W within the rotor blade. The figure shows a protective cup 10 arranged to assemble between the frame assembly 11 and the downward-facing suction side 20S airfoil surface; and another gasket 11P arranged to assemble between the frame assembly 11 and the upward-facing pressure side 20P airfoil surface. The protective cup 10 has a rigid housing 10H shaped to define a volume or cavity 10C that surrounds or encloses one or more additional devices 200 protruding from the airfoil surface. The cavity 10C defined by the housing 10H and the airfoil surface is filled with incompressible load-bearing material M. Seals 10S arranged around the perimeter of the housing 10H ensure that the load-bearing material M cannot escape during the lifting process. The frame assembly 11 of the conveying device 1 is connected to a lifting device such as a crane via an external structure 12 and lifting eyelets 13. As those skilled in the art will know, the frame assembly 11 can be opened and closed by means of remote control.

[0037] Figure 5 A protective cup 10 is shown in one possible embodiment of the invention. Here, the protective cup 10 is filled with a selected load-bearing material M before being pressed against the airfoil surface 20S. The figure shows a rotor blade 20 arranged such that the surface with the additional device 200 is arranged facing downwards. In this exemplary embodiment, the seal 10S is implemented as an inflatable chamber or tube that conforms to the surface of the rotor blade when inflated.

[0038] Figure 6Another possible embodiment of the invention is shown. The rotor blades 20 are arranged such that the surface carrying the attachment 200 faces upwards. A protective cup 10, mounted on a frame of the transport device 1, is positioned around a set of attachments 200. The frame assembly clamps around the rotor blades 20, such that pressure is applied to press the seal 10S against the rotor blade surface. In this exemplary embodiment, the protective cup 10 is equipped with a port 10P through which the carrier material M is introduced to fill the cavity 10C. In this exemplary embodiment, the seal 10S is implemented as a flexible lip that conforms to the surface of the rotor blade when pressed against it. In this case, the seal 10S faces inwards, such that the filler M presses against the seal 10S, thereby achieving optimal contact with the rotor blade surface throughout the transport process, thereby improving the effectiveness of the seal 10S. The carrier material M can be sand, water, gel, colloid, etc. For example, sand can be filled into the protective cup 10. Using sand (or any similar particulate material) as filler, the protruding attachments can be embedded in the particles. When the cover is pressed against the airfoil surface, the particles contact the rotor blade surface. The sand particles are pressed together, thus making contact through their numerous surfaces, and therefore, downward loads can be transferred very effectively to the frame assembly as the rotor blades are lifted, while the attachments are not subjected to any load and are optimally protected from damage. The filler can be simply dry sand, or a certain amount of water can be added to form a colloidal filler, further improving the effectiveness of load transfer within the cup.

[0039] The combination of insoluble particles and water can advantageously reduce lateral forces on the seal and is a preferred filler option in the case of relatively robust attachments. More vulnerable attachments may benefit from dry particles or other fillers, such as gels or colloids.

[0040] Alternatively, as explained above, the load-bearing material M can be any particulate or granular material that is substantially incompressible and will not adhere to the rotor blades, i.e., a material that will detach from the rotor blades 20 without any assistance. For example, a water-based gel can simply slide off the rotor blades 20 or be washed away by rainwater. The materials mentioned above are non-polluting and pose no environmental risk.

[0041] Of course, the features of the above embodiments, such as the selection of seals and packings, can be combined or interchanged in any reasonable way.

[0042] Figure 7A perspective view of the protective cup 10 as described above is shown. The figure shows the housing 10H and the seal 10S surrounding the perimeter of the housing 10H. A set of eddy current generators 200 are indicated by dashed lines, and the figure illustrates how these eddy current generators will be securely surrounded by the packing M when the cup 10 is positioned around the eddy current generators 200. When the seal 10S is pressed against the rotor blade surface, it prevents the load-bearing material M from escaping from the cup 10.

[0043] Figure 8 Another possible embodiment of the invention is shown. Here, the rotor blade 20 has an auxiliary device 200 on its suction side 20S and its pressure side 20P. The transport device 1 is equipped with a suitably arranged protective cup 10 for placement above the auxiliary device on the suction side 20S and the pressure side 20P, such that the auxiliary device 200 remains undamaged during the transport of the rotor blade. In this embodiment, two protective covers 10 are provided for each of the suction side 20S and the pressure side 20P.

[0044] Although the invention has been disclosed in the form of preferred embodiments and variations thereof, it will be understood that many additional modifications and variations can be made thereto without departing from the scope of the invention. For example, filling material may be collected after the handling operations are completed, for example by extracting the material through a port and conveying it to a storage container.

[0045] For clarity, it should be understood that the use of “a,” “an,” or “a” throughout this application does not exclude multiple, and “including” does not exclude other steps or elements.

Claims

1. A conveying device (1) for conveying wind turbine rotor blades (20), comprising: - Frame assembly (11), which is implemented as an assembly around the airfoil portion (20A) of the rotor blade (20); - A plurality of attachment covers (10) arranged to fit between the frame assembly (11) and the airfoil surface, wherein the attachment covers (10) are shaped to fit around the plurality of attachments (200); and - A substantially incompressible load-bearing material (M) for filling the additional device cover (10) when the additional device cover (10) is pressed against the rotor blade (20). The additional device cover (10) includes a seal (10S) arranged around the periphery of the housing (10H) to prevent the substantially incompressible load-bearing material (M) from escaping during the lifting process.

2. The conveying device according to claim 1, wherein, The attachment cover (10) includes a rigid housing (10H) adapted to be mounted to the frame assembly (11).

3. The conveying device according to claim 1 or 2, wherein, The seal (10S) is implemented as any of the following: an inflatable chamber, a flexible lip, or a gasket.

4. The conveying device according to claim 3, wherein, The seal (10S) is shaped with its face facing inward.

5. The conveying device according to claim 1 or 2, wherein, The carrier material (M) includes any of the following: microparticles, gels, colloids, and liquids.

6. The conveying device according to claim 1 or 2, wherein, The load-bearing material (M) is water-soluble and / or non-sticky.

7. The conveying device according to claim 1 or 2, wherein, The attachment cover includes a port (10P) for conveying the load-bearing material (M) into the cavity (10C) when the attachment cover (10) is pressed against the rotor blade (20).

8. The conveying device according to claim 1 or 2, wherein, The auxiliary device cover (10) is arranged for placement along the maximum thickness region of the airfoil (20A).

9. A method for handling a wind turbine rotor blade (20) equipped with a surface attachment device (200), the method comprising the following steps: - The rotor blades (20) are arranged such that their airfoil portions (20A) are in a substantially horizontal orientation; - A frame assembly (11) of the conveying device (1) according to any one of claims 1 to 8 is arranged around the airfoil portion (20A) of the rotor blade (20). - An attachment cover (10) of the conveying device (1) is arranged around a plurality of attachments (200); - Press the additional device cover (10) against the rotor blade (20); - Fill the additional device cover (10) of the conveying device (1) with incompressible load-bearing material (M).

10. The method according to claim 9, comprising the steps of: connecting the conveying device (1) to the lifting equipment and lifting the rotor blades (20) to the height of the hub (21).

11. The method according to claim 9 or 10, comprising the initial step of arranging the rotor blades (20) so that their suction side faces downward.

12. The method according to claim 9 or 10, wherein, The step of pressing the auxiliary device cover (10) against the rotor blade (20) precedes the step of filling the bearing material (M) into the auxiliary device cover (10).

13. The method according to claim 9 or 10, comprising the step of introducing particulate material and liquid into the auxiliary device cover (10) such that the carrier material (M) contains the particles and the liquid.

14. The method according to claim 9 or 10, wherein, The step of arranging the frame assembly (11) around the airfoil (20A) is performed after the final manufacturing stage of the rotor blade (20), and the attachment cover (10) is released after the rotor blade (20) is installed into the hub (21) of the wind turbine (2).

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