WO2011098086A1

WO2011098086A1 - A system and method for transporting a wind turbine component

Info

Publication number: WO2011098086A1
Application number: PCT/DK2011/050038
Authority: WO
Inventors: Gunnar Kamp Storgaard Pedersen
Original assignee: Vestas Wind Systems A/S
Priority date: 2010-02-12
Filing date: 2011-02-11
Publication date: 2011-08-18

Abstract

A system for transporting a wind turbine component generally comprises first and second railcars, a first support member configured to support a first portion of the wind turbine component on the first railcar, and a second support member configured to support a second portion of the wind turbine component on the second railcar. The first support member is rotatably and slidingly coupled to the first railcar so that it is rotatable relative to the first railcar about a vertical axis and slidable along a length of the first railcar. The second support member is rotatably coupled to the second railcar so that it is rotatable relative to the second railcar about a vertical axis. A corresponding method is also disclosed.

Description

A SYSTEM AND METHOD FOR TRANSPORTING A WIND TURBINE COMPONENT

Cross-Reference

[0001] This application claims the benefit of U.S. Application No. 61/303,697, filed on February 12, 2010.

Technical Field

[0002] The present invention relates generally to the transportation of wind turbine components, and more specifically to a system and method for transporting one or more wind turbine components by railcar.

Background

[0003] Wind turbines have long been used to convert the kinetic energy of the wind into mechanical energy that rotates the shaft of a generator, thereby producing electricity. Over time, there has been a significant increase in the overall size of these machines because of the desire to capture more of the wind's available energy. This has made handling their components very challenging, particularly in terms of transportation.

[0004] For example, some modern-day, megawatt-scale wind turbines include towers more than 100 meters tall. Many of the towers are assembled from tubular sections of rolled steel plates that are welded together at a factory. The tubular sections are then transported to the wind site and joined together by a flange connection or the like because welding them at the site is not practical and/or economical. But joining the tower sections is an additional assembly step nonetheless, and the joint's effect on the overall structural integrity of the tower must be taken into account when designing the tower. These considerations make it desirable to produce long tower sections and thereby minimize the number of joints. Some tubular tower sections may be longer than 30 meters and have relatively large diameters due to a tapered design.

[0005] The blades of a modern-day, megawatt-scale wind turbine may be even larger components produced at a factory, with some blades being longer 50 meters. The blades are typically produced by laying materials into moulds configured to form blade shells, curing the materials, and then closing the moulds and bonding the shells together. Such a technique is desirable to help optimize weight and stiffness, which might otherwise be compromised if blades were produced in two or more sections intended to be assembled at the wind turbine site by a specially-designed joint.

[0006] As can be appreciated, these and other considerations result in large wind turbine components that must be transported from a factory. Wind turbine sites are typically in remote locations such that the components must be transported by road, sea, and/or rail, each of which involves numerous restrictions. With rail, the lengths of railcars are limited because of curvature in the track profiles they must travel along. Stabilizing a wind turbine component that is longer than the railcar can be a difficult task. Moreover, there are typically height and width restrictions on the cargo carried by railcars because of tunnels, bridges, and other objects along the track. These restrictions make it even more difficult to design effective solutions. Therefore, systems and methods for transporting wind turbine components that address these challenges are highly desirable.

Summary

[0007] A system for transporting a wind turbine component generally comprises first and second railcars, a first support member configured to support a first portion of the wind turbine component on the first railcar, and a second support member configured to support a second portion of the wind turbine component on the second railcar. The first support member is rotatably and slidingly coupled to the first railcar so that it is rotatable relative to the first railcar about a vertical axis and slidable along a length of the first railcar. The second support member is rotatably coupled to the second railcar so that it is rotatable relative to the second railcar about a vertical axis. This effectively allows the first and second railcars to support the wind turbine component, which has a fixed length, even though the distance between points on the railcars themselves may change due to curves in the railroad track.

[0008] In one embodiment, the first support member comprises a saddle mounted to the first railcar, a carriage that slides within the saddle, and a support element that rotates on the carriage. Such an arrangement isolates the rotating and sliding functions to allow for a robust design with a simplified construction. The saddle may be at least partially positioned within a recessed area of the first railcar, which means that the wind turbine component is supported closer to an upper surface of the railcar. This has the advantage of reducing the overall cargo height defined by the wind turbine component to more easily meet height restrictions and similar transportation requirements. [0009] In a further aspect or embodiment, the first and second support members support the wind turbine component at locations spaced from first and second ends of the wind turbine component. Such an arrangement allows the ends to be located over land on an outer side of a curve in the railroad track and a middle portion of the wind turbine component to be located over land on an inner side of the curve. Otherwise the wind turbine component would extend further over land on the inner side of the curve. Thus, the arrangement helps optimize the use of space to meet restrictions and avoid hitting objects.

[0010] A corresponding method for transporting a wind turbine component is also disclosed. The method generally comprises coupling a first railcar to a second railcar, coupling first and second support members to the respective first and second railcars, coupling first and second portions of the wind turbine component to respective the first and second support members, and moving the first and second railcars along a railroad track. Again, the first support member is rotatable relative to the first railcar about a vertical axis and slidable along the length of the first railcar, and the second support member is rotatable relative to the second railcar about a vertical axis. This provides the same advantages of the system mentioned above.

[0011] In a further aspect or embodiment, the wind turbine component is a first wind turbine blade. A transportation casing is secured to the first wind turbine blade and includes first and second parts that define an inner surface corresponding to the first portion of the first wind turbine blade. The first and second parts are substantially solid bodies comprised of a synthetic polymer. The transportation casing is then positioned within a frame mounted to the first support member. Such a transportation casing helps protect the blade and allows for efficient transportation. The transportation casing, for example, may be the same one used when transporting the blade (e.g., by land, sea, or some combination thereof) to the site where the first and second railcars are loaded.

[0012] These and other aspects, together with their advantages, will become more apparent based on the description below.

Brief Description of the Drawings

[0013] Fig. 1 is a perspective view of one embodiment of a wind turbine.

[0014] Figs. 2 and 3 are perspective views of a system for transporting a wind turbine tower section. [0015] Fig. 4 is a perspective view of a first support member used in the system shown in Figs. 2 and 3.

[0016] Fig. 5 is an exploded perspective view of the first support member shown in Fig. 4.

[0017] Figs. 6A and 6B are diagrammatic views illustrating a wind turbine tower section being transported along a railroad track using the system shown in Figs. 2 and 3.

[0018] Fig. 7 is a side elevation view of a system for transporting one or more wind turbine blades.

[0019] Fig. 8 is a front elevation view of a frame and casing used with the system shown in Fig. 7.

[0020] Figs. 9 and 10 are perspective views of one embodiment of a casing represented in Fig. 8.

[0021] Fig. 11 is a perspective of another embodiment of a casing.

Detailed Description

[0022] Fig. 1 shows one embodiment of a wind turbine 10 after it has been erected. The wind turbine 10 generally comprises a tower 12, a nacelle 14 supported by the tower 12, a hub 16 rotatably mounted to the nacelle 14, and a set of blades 28 coupled to the hub 16. These components and/or their subcomponents were all transported to the site where the wind turbine 10 is located and subsequently assembled. Indeed, the description below focuses on a system and method for transporting wind turbine components rather than their assembly at the wind turbine site. Although particular embodiments will be described for certain wind turbine components, other embodiments may be possible based upon the same general principles.

[0023] To this end, Figs. 2 and 3 illustrate a system 20 for transporting a tower section 22 of the wind turbine 10. The system 20 includes first and second railcars 24, 26, a first support member 28 supporting a first portion 30 of the tower section 22 on the first railcar 24, and a second support member 32 supporting a second portion 34 of the tower section 22 on the second railcar 26. The first support member 28 is rotatingly and slidingly coupled to the first railcar 24. As will be described in greater detail below, this means that the first support member 28 is rotatable relative to the first railcar 24 about a vertical axis and slidable along a length of the first railcar 24.

[0024] The second support member 32 is likewise rotatingly coupled to the second railcar 26 and, therefore, rotatable relative to the second railcar 26 about a vertical axis. However, the second support member 32 may be fixed relative to the longitudinal axis of the second railcar 26 such that there is no sliding movement. This type of arrangement makes the positioning of the tower section 22 relative to the first and second railcars 24, 26 more predictable as they move along a railroad track.

[0025] Figs. 4 and 5 illustrate the first support member 28 in further detail. In the embodiment shown, the first support member 28 includes a saddle 40, a carriage 42 that slides within the saddle 40, and a support element 44 that rotates on the carriage 42. The sliding movement may be accomplished by a track and rollers. For example, the saddle 40 defines a body 46 having rails 48 aligned parallel to a longitudinal axis of the first railcar 24 (Fig. 2) when the saddle 40 is mounted. The carriage 42 is suspended within the body 46 by rollers 50 received in the rails 48. Because the rails 48 define a track along which the rollers 50 can move, the carriage 42 can slide relative to the first railcar 24 along the railcar's longitudinal axis.

[0026] The carriage 42 includes a pin 54 extending along a vertical axis, and the support element 44 is mounted on the pin in a manner that allows it to rotate about the vertical axis. If desired, a track and rollers may also be provided to facilitate this rotation. Figs. 4 and 5 show circular plates 56, 58 centered on the pin 54 with a hub 60 and rollers 62 located between them. The rollers 62 are configured to move around the pin 54 along the periphery of the circular plates 58, 60 and help provide support for the load carried by the support element 44.

[0027] As can be appreciated, the sliding and rotating of the first support member 28 are carried out by different components. Isolating the sliding and rotating functions in such a manner not only simplifies construction of the first support member 28, but also allows for a robust design.

[0028] Another advantage may be obtained by at least partially locating the body 46 of the saddle 40 within a recessed area of the first railcar 24. Fig. 2 shows the first railcar 24 including several recessed areas 70 in the form of open pockets in an upper surface 72 of the first railcar 24. The saddle 40 includes arms 74 supported by and mounted to the upper surface 72 so that the body 46 is suspended within one of the recessed areas 70. As a result, the carriage 42 and support element 44 are positioned at a lower elevation. A frame 76 may be used to help stabilize the first portion 30 of the tower section 22 on the support element 44, but the low position of the support element 44 helps keep the frame 76 and tower section 22 close to the upper surface 72. Accordingly, the overall height of the system 20 is minimized thereby facilitating compliance with height restrictions, etc. [0029] Again, the second support member 32 may not be slidable like the first support member 28. Instead, the second support member 32 may simply include a rotatable connection, such as one similar to the pin 54 (Figs. 4 and 5) and support element 44 of the first support member 28. The second support member 32 may also include something similar to the saddle 40 mounted in a recessed manner relative to an upper surface 78 of the second railcar 26, if desired.

[0030] Referring to Figs. 6A and 6B, a method of transporting the tower section 22 with the system 20 will now be described. The first railcar 24 is first coupled to the second railcar 26 using

conventional methods. Although Figs. 6A and 6B show the first and second railcars 24, 26 being serially connected with no intervening railcars, in alternative embodiments one or more railcars may be positioned between the first and second railcars 24, 26. Regardless, the first and second portions 30, 34 of the tower section 22 are secured to the respective first and second support members 28, 32, which in turn are coupled to the respective first and second railcars 24, 26 as discussed above. The order in which these steps occur may vary depending on the particular embodiment and circumstances.

[0031] When moving along a straight section of a railroad track 86, as shown in Fig. 6A, the longitudinal axes of the first and second railcars 24, 26 are aligned or substantially aligned. The tower section 22 is centered or substantially centered along these axes, but may include portions wider than the first and second railcars 24, 26 when viewed from above. Thus, the actual "footprint" of the system 20 (i.e., ground area over which the system 20 projects) may include small portions on each side of the first and second railcars 24, 26. The overall length of the system 20, however, is generally defined by the lengths of the first and second railcars 24, 26 because the tower section 22 is shorter than their combined length and supported between their ends.

[0032] When moving along a curve in the railroad track 86, as shown in Fig. 6B, the longitudinal axes of the first and second railcars 24, 26 are no longer aligned. The combined length decreases when measured along a straight line between the ends of the first and second railcars 24, 26. The tower section 22, however, is a structure with a fixed length. To account for this, the first support member 28 slides along the length of the first railcar 24 and rotates about a vertical axis. The second support member 32 rotates about a vertical axis as well. A middle portion 88 of the tower section 22 located between the first and second portions 30, 34 is then suspended over land on an inner side of the curve to a greater extent than when the first and second railcars 24, 26 move along a straight section of the railroad track 86 (Fig. 6A). [0033] In embodiments like the one shown, the first and second support members 28, 32 may support the first and second portions 30, 34 of the tower section 22 at locations spaced apart from ends 92, 94 of the tower section 22. Such an arrangement enables more of the tower section 22 to be positioned over land on an outer side of the curve. More specifically, the ends 92, 94 (or at least portions thereof) are positioned on the outer side of the curve, outside of the footprint of the first and second railcars 24, 26. This effectively reduces the extent to which the middle portion 88 is positioned on the inside of the curve. By distributing portions of the tower section 22 on both sides of the curve, the use of space is optimized to facilitate compliance with width restrictions and to help avoid striking objects positioned close to the railroad track 86. Indeed, as shown in Fig. 6b, end 92 and/or end 94 may project over land on an outer side of the curve by a first distance dl measured perpendicular to the railroad track 86, and the middle portion 88 may project over land on the inner side of the curve by a second distance d2 measured perpendicular to the railroad track 86. The first and second distances dl, d2 may be approximately equal so that no portion of the tower section 22 projects too far outwardly on either side of the railroad track 86.

[0034] Although the system 20 is described above for transporting a tower section, similar systems may be used to transport other wind turbine components. Figs. 7 and 8 illustrate a system 100 configured to transport one or more wind turbine blades 102. The system 100 also includes a first support member 104 slidingly and rotatingly coupled to a first railcar 106 and a second support member 108 rotatingly coupled to a second railcar 1 10. The first and second support members 104, 108 operate upon the same principles as the first and second support members 28, 32 even though their constructions may differ due to the type of component being supported. Accordingly, the general advantages discussed above may equally apply to the system and only additional or different aspects will be described below.

[0035] Rather than transporting a single wind turbine component like the system 10, the system 100 is configured to transport multiple components. There are two wind turbine blades 102 shown in Figs. 7 and 8— a first wind turbine blade 102a and a second wind turbine blade 102b. The first wind turbine blade 102a comprises a root 1 18a, a tip 120a, and first and second portions 122a, 124a spaced from the root 1 18a and tip 120a. The first support member 104 supports the first portion 122a, and the second support member 108 supports the second portion 124a. Thus, the root 118a overhangs (i.e., is suspended over) a portion of the first railcar 106 and the tip 120a overhangs a portion of the second railcar 108. [0036] The second wind turbine blade 102b may have the same construction as the first wind turbine blade 102a, but is supported in an opposite manner. That is, the first support member 104 supports the second portion 124b of the second wind turbine blade 102b, and the second support member 108 supports the first portion 122b of the second wind turbine blade 102b. Thus, the root 1 18b and tip 120b are located adjacent the tip 120a and root 1 18a, respectively, which is sometimes referred to as a "root-to-tip" or "nose-to -tail" configuration.

[0037] The exact manner in which the first and second blades 102a, 102b are supported by the first and second support members 104, 106 may vary. In one embodiment, frames 130 are mounted to the first and second support members 104, 108. The frames 130 receive transportation casings 132, 134 in which the first and second portions 122, 124 of the blades 102 are held. Similar frames and

transportation casings are described in Danish Patent Application No. PA 2009 00378 and U.S.

Provisional Patent Application No. 61/161,102, the disclosures of which are incorporated herein by reference.

[0038] In particular, those applications disclose embodiments of a transportation casing formed from two parts, examples of which are shown in Figs. 9 and 10 with one transportation casing being designated by reference number 140 and another transportation being designated by reference number 142. Parts 140a, 140b of transportation casing 140 are substantially solid bodies predominately comprised of a synthetic polymer (e.g., foam). When the parts 140a, 140b are assembled using circumferential straps (not shown) that may be received in grooves 144, the casing 140 defines an inner surface 146 corresponding to a section of the wind turbine blade 102 to be transported. The parts 140a, 140b in combination form a self-supporting structure in the sense that when transporting a wind turbine blade, the transport casing 140 is able to mechanically stand alone for an extended period of time without substantially deteriorating. The casings may additionally or alternatively be supported within a surrounding frame 150, as shown in Fig. 11.

[0039] The applications mentioned above also describe how the casings may be designed to meet the demands of all forms of transportation throughout the logistic chain. The casings 132, 134 in the system 100 (Figs. 8 and 9) may be the same ones used to transport the blades to the site where the first and second railcars 106, 110 are loaded. Thus, the system 100 helps contribute to the efficient handling of the first and second wind turbine blades 102a, 102b. [0040] As with the tower section 22, the first and second blades 102a, 102b have a fixed length. To account for the decrease in distance between a point on the first railcar 106 and a point on the second railcar 1 10 when travelling along a curve in a railroad track, the first support member 104 slides along the length of the first railcar 106. Additionally, both the first and second support members 104, 108 rotate about respective vertical axes. Thus, the principles and advantages discussed above with respect to the system 10 apply equally to the system 100. Middle portions 126a, 126b of the first and second blades 102a, 102b may be suspended over land on an inner side of the curve, while the roots 118a, 118b and tips 120a, 120b may be suspended over land on an outer side of the curve.

[0041] The embodiments described above are merely non-limiting examples of the invention defined by one or more of the claims that appear below. Persons skilled in the technical field of handling wind turbine components will appreciate additional examples, modifications, and advantages based on the description. For example, the first and second blades 102a, 120b may be stacked in a root-to-tip configuration when supported on the first and second railcars 104, 1 10, rather than being positioned side -by-side as shown in the figures. The patent applications mentioned above describe such a stacking arrangement. Furthermore, there may be more than two blades, or more than one tower section, supported by the first and second support members. Again, the exact manner in which wind turbine components are secured to the first and second support members are will depend on the particular circumstances.

[0042] Additionally, although the second support member 32 is described above as not being slidable along the second railcar 26, in alternative embodiments there may be some sliding movement along the railcar's longitudinal axis. Indeed, the sliding movement may even be a safety feature. For example, the second support member 32 may be configured to slide only when forces exceed a certain amount. High forces may be present if the first support member 28 locks up or otherwise does not function properly. In this manner, the slidable nature of second support member 32 serves as a backup so that the system 20 still functions as intended.

[0043] In view of the above, departures may be made from the details of the disclosed embodiments without departing from the inventive concept defined by the claims below.

Claims

1. A system for transporting a wind turbine component, comprising:

a first railcar having a length along a longitudinal axis;

a first support member rotatably and slidingly coupled to the first railcar and configured to support a first portion of the wind turbine component, the first support member being rotatable relative to the first railcar about a vertical axis and slidable along the length of the first railcar;

a second railcar coupled to the first railcar and having a length along a longitudinal axis; and a second support member rotatably coupled to the second railcar and configured to support a second portion of the wind turbine component, the second support member being rotatable relative to the second railcar about a vertical axis.

2. A system according to claim 1, wherein the first support member comprises a saddle mounted to the first railcar, a carriage that slides within the saddle, and a support element that rotates on the carriage.

3. A system according to claim 2, wherein the first railcar includes an upper surface generally extending across at least a substantial portion of the length of the first railcar and a recessed area located below the upper surface, the saddle being at least partially positioned within the recessed area.

4. A system according to any of claims 1-3, further comprising:

a wind turbine component having a first end and a second end, wherein the first support member supports the wind turbine component at a location spaced from the first end.

5. A system according to claim 4, wherein the wind turbine component is a first wind turbine blade having a root, a tip, and first and second portions spaced from the root and tip, wherein the first support member supports the first portion of the first wind turbine blade such that the root overhangs a portion of the first railcar, and wherein the second support member supports the second portion of the first wind turbine blade such that the tip overhangs a portion of the second railcar.

6. A system according to claim 5, further comprising: a second wind turbine blade having the same construction as the first wind turbine blade, wherein the first support member supports the second portion of the second wind turbine blade and the second support member supports the first portion of the second wind turbine blade.

7. A system according to claims 5 or 6, further comprising:

a transportation casing secured to the first wind turbine blade, the transportation casing including first and second parts cooperating to define an inner surface corresponding to the first or second portion of the first wind turbine blade, the first and second parts being substantially solid bodies comprised of a synthetic polymer; and

a frame mounted to the first support member and configured to receive the transportation casing.

8. A method for transporting a wind turbine component, comprising:

coupling a first railcar to a second railcar, the first and second railcars each having a length along a longitudinal axis;

coupling first and second support members to the respective first and second railcars, the first support member being rotatable relative to the first railcar about a vertical axis and slidable along the length of the first railcar, and the second support member being rotatable relative to the second railcar about a vertical axis;

coupling first and second portions of the wind turbine component to the respective first and second support members; and

moving the first and second railcars along a railroad track.

9. A method according to claim 8, wherein moving the first and second railcars further comprises: moving the first and second railcars along a curve in the railroad track, the first support member sliding and rotating in response to such movement, and the second support member rotating in response to such movement so that a middle portion of the wind turbine component between the first and second portions is positioned over land on an inner side of the curve, outside of a footprint of the first and second railcars.

10. A method according to claim 9, wherein the first portion of the wind turbine component is spaced apart from a first end of the wind turbine component, and wherein when moving the first and second railcars along the curve, the first end projects over land on an outer side of the curve by a first distance measured perpendicular from the railroad track, and the middle portion projects over the land on the inner side of the curve by a second distance measured perpendicular, the second distance being approximately equal to the first distance.

1 1. A method according to any of claims 8-10, wherein the first and second portions of the wind turbine component are spaced apart from first and second ends of the wind turbine component, the first and second ends being positioned over land on an outer side of the curve, outside of a footprint of the first and second railcars, when moving the first and second railcars along the curve.

12. A method according to any of claims 8-1 1 , wherein the first and second portions of the wind turbine component are coupled to the respective first and second support members before coupling the first and second support members to the respective first and second railcars.

13. A method according to any of claims 8-12, wherein the first support member comprises a saddle, a carriage that slides within the saddle, and a support element that rotates on the carriage, and wherein coupling the first and second support members to the respective first and second railcars comprises: mounting the saddle to the first railcar.

14. A method according to claim 13, wherein the first railcar includes an upper surface and a recessed area located below the upper surface, and wherein mounting the saddle comprises:

at least partially positioning the saddle within the recessed area of the first railcar so that the wind turbine component is supported close to the upper surface of the first railcar.

15. A method according to any of claims 8-14, wherein the wind turbine component is a first wind turbine blade, and wherein coupling the first and second portions of the wind turbine component to the respective first and second support members comprises:

securing a transportation casing to the first wind turbine blade, the transportation casing including first and second parts cooperating to define an inner surface corresponding to the first portion of the first wind turbine blade, the first and second parts being substantially solid bodies comprised of a synthetic polymer; and positioning the transportation casing within a frame mounted to the first support member.

16. A method according to claim 15, further comprising:

transporting the first wind turbine blade to the first and second railcars, wherein the transportation casing is secured to the first wind turbine blade before it is transported to the first and second railcars.

17. A method according to any of claims 8-16, wherein the wind turbine component is a first wind turbine blade, the method further comprising:

providing a second wind turbine blade having the same construction as the first wind turbine blade; and

coupling the first portion of second wind turbine blade to the second support member and the second portion of the second wind turbine blade to the first support member.