EP2527284B1

EP2527284B1 - System and method for handling wind turbine tower sections

Info

Publication number: EP2527284B1
Application number: EP11194018.5A
Authority: EP
Inventors: Gunnar K. Storgaard Pedersen
Original assignee: Vestas Wind Systems AS
Current assignee: Vestas Wind Systems AS
Priority date: 2011-12-16
Filing date: 2011-12-16
Publication date: 2016-04-20
Anticipated expiration: 2031-12-16
Also published as: DK2527284T3; EP2527284A1; ES2572738T3

Description

Technical Field

The present invention relates to handling wind turbine components, and more specifically to a lifting tool, system, and method for handling wind turbine tower sections.

Background

Wind turbines have long been used to convert the kinetic energy of wind into mechanical energy that drives 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. Nevertheless, there remain sites better suited for smaller wind turbines due to their wind conditions, local restrictions, or other limiting factors. A great variety of wind turbine sizes now exist as a result, which makes handling their components very challenging particularly in terms of transportation and storage.
For example, many wind turbine towers are assembled from annular sections of rolled steel. The sections are welded together at a factory to form cylindrical or conical tubes. The tubular sections are then transported to the intended wind turbine site and joined together by flange connections provided on their ends. The size of these components varies depending on the size of the particular tower being built and their location within that tower. Diameters, for example, may range from approximately 2 to 5 meters. This may in turn create the need for different sizes of handling tools. Additionally, however, the intended sites are often located far away from the tower factories, meaning that the tower sections are often handled several times before reaching the sites. The handling could be unloading from a transportation vehicle to storage (or vice-versa), the transfer from one form of transportation to another (e.g., land to sea), etc. The handling tools/equipment must typically be readily available. If many different sizes of handling tools must be kept on hand, this can be cumbersome and costly.
A lifting tool allowing lifting of different tower sections is known from Applicant's WO2008/000262A in which attachment points are relatively adjustable on the tool through an eccentric movement in order to accommodate different tower sections.

Summary

A lifting tool, system, and method for handling one or more wind turbine tower sections are described below. The tower sections to be handled each have an end with a flange extending along a radius of curvature and bolt holes extending through the flange.
In general, the lifting tool comprises a bracket and insert. The bracket has a base and an adaptor hole extending through the base. The insert is configured to be positioned and retained in and/or over the adaptor hole. Additionally, the insert includes bolt holes arranged along a first radius of curvature corresponding to the radius of curvature of the flange of one of the tower sections. In this way, the bolt holes in the insert are configured to be aligned with the bolt holes in the flange of the tower section so that the bracket is configured to be bolted to the tower section.
The lifting tool may actually include a plurality of inserts configured to be positioned and retained in and/or over the adaptor hole. At least some of the inserts have bolt holes arranged along a second radius of curvature different than the first radius of curvature. This enables the lifting tool to be used to handle a tower section that has a different size. A different insert is simply selected. Thus, the lifting tool can easily be used to handle different sizes of tower sections without significant reconfiguration. All that is needed is different sets of inserts with bolt holes arranged along different radii of curvature. The different sets of inserts may also have different bolt hole patterns, such as single and double rows of bolt holes, to further accommodate different flange designs.
The system for handling one or more wind turbine tower sections comprises first and second lifting tools with the construction described above. A support member may be coupled to the first and second lifting tools so as to extend therebetween. This support member may have an adjustable length to facilitate use with different sizes of tower sections.
The method for handling one or more wind turbine tower sections involves providing at least one lifting tool with the construction described above. The lifting tool is coupled to a first tower section by positioning the base of the lifting tool over the flange of the first tower section. The insert to be used with the lifting tool is positioned and retained in and/ or over the adaptor hole before or after this step. The base is eventually secured to the end of the first tower section by bolting the insert to the flange. Finally, the first tower section is lifted with the lifting tool. Two or more lifting tools may be provided, along with a support member extending between them, as mentioned above.

Brief Description of the Drawings

Fig. 1 is a perspective view of a wind turbine tower section and one embodiment of a system for handling the tower section.
Fig. 2 is a perspective view of the system of Fig. 1.
Fig. 3 is an enlarged view of a lifting tool used in the system of Fig. 1.
Fig. 4 is an exploded perspective view of the lifting tool shown in Fig. 3.
Fig. 5 is a perspective of an insert of the lifting tool of Fig. 3.

Detailed Description

Figs. 1 and 2 show one embodiment of a system 10 for handling wind turbine tower sections. In general, the system 10 includes one or more lifting tools 12 for handling a tower section 14 and a support bar or member 16 to which the lifting tools 12 are coupled. These components and use of the system 10 will be described in further detail below. The details of the tower section 14 will also be described, but only for background purposes as the system 10 may be used to handle other tower sections and other types of towers.
The tower section 14 part of tubular steel tower and constructed from several steel rings welded together. A flange 22 with bolt holes 24 is provided on a first end 26 of the tower section to facilitate attachment to other tower sections or to a foundation. A second end (not shown) of the tower section 14 may have a similar arrangement with a flange. The tower section 14 is slightly conical such that the flange 22 on the first end 26 extends along a first radius of curvature and the flange on the second end extends along a second radius of curvature. The tower section 14 may alternatively be cylindrical with both flanges extending along similar radii of curvature.
Referring to Figs. 3 and 4, one of the lifting tools 12 is shown. The lifting tool 12 includes a bracket 30 and insert 32. The bracket 30 has a base 34, an adaptor hole 36 extending through the base 34, and at least two walls 38 extending upwardly from the base 34. In the embodiment shown, first and second walls 38a, 38b located on opposite sides of the adaptor hole 36 are provided. The base 34 and walls 38 are constructed from plates or other pieces of metal (e.g., steel) welded together to define the desired structure of the bracket 30. Alternatively, the bracket 30 may be cast from a metal (e.g., iron) so that the base 34 and walls 38 are formed together. Other ways of constructing the bracket 30 will be appreciated by skilled persons.
The insert 32 is configured to be at least partially positioned and retained in and/or over the adaptor hole 36. This may be achieved by designing the insert 32 with appropriate geometry. For example, and as shown in Fig. 5, the insert 32 may have a head or top portion 40 larger than the adaptor hole 36 and a neck or body portion 42 shaped to fit in the adaptor hole 36. Thus, the head portion 40 rests against a surface 44 (Fig. 4) of the bracket 30 to prevent the insert 32 from being pushed or pulled through the adaptor hole 36 when the insert 32 is used with the bracket 30. Skilled persons will appreciate other geometries providing the same effect, such as designing the adaptor hole 36 and insert 32 with tapered profiles. Alternatively or additionally, the insert 32 may be retained by separately securing the insert 32 to the bracket 30 with bolts 46 or other conventional fasteners (e.g., clamps, latches).
The insert 32 includes one or more bolt holes 50 arranged along a radius of curvature corresponding to that of one of the flanges 22 (Fig. 1; measured at the bolt holes 24) when the insert 32 is positioned in the adaptor hole 36. Thus, the bolt holes 50 are arranged along the first or second radius of curvature mentioned above. The spacing of the bolt holes 50 also corresponds to the spacing of the bolt holes 24. This matching of curvature and spacing enables the bolt holes 50 to be aligned with the bolt holes 24 so that the lifting tool 12 may be secured to the flanges 22 via bolts (not shown) extending through the insert 32.
The lifting tool 12 further includes a gripping element 60 extending between the first and second walls 38a, 38b. In the embodiment shown, the gripping element 60 comprises a pin 62 coupled to the first and second walls 38a, 38b and a sleeve (or "rounding") 64 rotatably supported by the pin 62 between the first and second walls 38a, 38b. Such an arrangement enables a sling 66 (Fig. 1), hook, cable or other crane accessory to grip the lifting tool 12 so that the tower section 14 to which the lifting tool is secured may be handled. The pin 62 carries most of the load, while the sleeve 64 allows the sling 66 or other crane accessory to roll over the pin if needed.
The system shown in Figs. 1 and 2 includes first and second lifting tools 12a, 12b. The support member 16 to which the first and second lifting tools 12a, 12b are coupled has an adjustable length. For example, and as shown, the support member 16 may comprise telescopic tubes. The adjustable length ensures that the support member 16 may be used with the first and second lifting tools 12a, 12b on tower sections with different diameters. This feature of accommodating different tower sections will be described in further detail below, after describing a method for handling the tower section 14 with the system 10.
In use, the first lifting tool 12a is coupled to the tower section 14 in the manner described above. Thus, the base 34 of the lifting tool 12 is positioned over the flange 22 of the tower section 14. The insert 32 is then positioned and retained in and/or over the adaptor hole 36 in the base 34 (unless this step was already done previously). Finally, the base 34 is secured to the first end 26 of the tower section by bolting the insert 32 to the flange 22.
If not already done so, the gripping element 60 is then assembled. The sleeve 64 is positioned between the first and second walls 38a, 38b, and the pin 62 is inserted through the sleeve 64 via holes 68 in the walls 38. Linch pins 70, bolts, or the like are used to secure the pin 62.
The second lifting tool 12b is coupled to a different location on the flange 22 in the same manner as the first lifting tool 12a. In the embodiment shown, the second lifting tool 12b is coupled to the flange 22 at a diametrically opposite location from the first lifting tool 12a. The support member 16 is then secured to the first and second lifting tools 12a, 12b after adjusting its length accordingly. Alternatively, the support member 16 may be secured to the first and second lifting tools 12a, 12b before they are coupled to the tower section 14. In such a scenario separate tubes may be secured to the first and second lifting tools 12a, 12b before being inserted into each other and adjusting the length of the support member 16. The length of the support member 16 is locked after adjustment regardless which of these approaches is taken.
Finally, the tower section 14 is lifted with the first and second lifting tools 12a, 12b. This may be accomplished by coupling slings 66 to the first and second lifting tools 12a, 12b, as schematically shown in Fig. 1. The slings 66 are wrapped around the gripping elements 60 and then hooked onto or otherwise secured to a lifting component (not shown), such as a hook of a crane.
It is possible to use the system 10 to handle tower sections of various sizes. Although the diameter of the flanges on the ends of the tower sections may vary, for each lifting tool 12 there may be a plurality of inserts 32 configured to be positioned and retained in and/or over the adaptor hole 36. At least some of the inserts 32 have bolt holes arranged along a radius of curvature different than the first radius of curvature. Thus, in the method described above, one of the initial steps would be to select inserts 32 for the first and second lifting tools 12a, 12b with a radius of curvature corresponding to the radius of curvature of the flange 22 of the tower section 14. After the system 10 is used to lift or otherwise handle the tower section 14, the first and second lifting tools 12a, 12b may be removed and used to handle a second tower section that has a different diameter. This involves selecting an insert 32 for each of the first and second lifting tools 12a, 12b with a radius of curvature (of the bolt holes) corresponding to the radius of curvature of a flange of the second tower section.
As can be appreciated, the system 10 provides more than just an easy means of securing a lifting tool to a wind turbine tower section. The ability to accommodate different inserts enables the system 10 to be used for various sizes of tower sections without significant reconfiguration. The design of the system itself has additional benefits. In particular, the system 10 provides the above-described flexibility without having to incorporate adjustable locking elements in the lifting tools 12. The result is a reliable, simplified construction that can be economically produced.
Furthermore, the components of the system 10 may be constructed to facilitate handling. For example, the brackets 12 and inserts 32 may be constructed from materials with different densities. A heavier, stronger material may be used for the brackets 12, while a lighter material may be used for the inserts 32. In one specific embodiment, the brackets 12 may be constructed from steel or iron while the inserts 32 may be constructed from aluminum. Using different materials for the brackets 12 and inserts 32 enables the system 10 to be optimized for both performance (e.g., bearing loads) and handling.
Other examples, modifications, and advantages of the system 10 will be readily apparent to persons skilled in the handling of wind turbine components. This includes using the system 10 with a different number of the lifting tools 12. For example, in some embodiments only a single lifting tool may be used. In other embodiments, three or more lifting tools may be used. The support member to which the lifting tools are coupled may have a star-like shape or other appropriate geometry in such embodiments due to the different number of lifting tools.
The lifting tools themselves may be configured differently as well. For example, the gripping element may be an integral portion of the bracket. Alternatively, the gripping element may be part of or secured to the insert rather than the bracket. Even further, one or more gripping elements may be positioned on the support member instead of the lifting tools.
Further variations will be appreciated based on the tower section to be handled. For example, if the tower section includes a flange with two rows of bolt holes, the inserts may likewise have two rows of bolt holes with radii of curvature matching that of the rows of bolt holes on the flange. And although the system has been described in connections with a tubular steel tower, the system may in fact be used with any tower section having an end with bolt holes, including tower sections with intermediate portions constructed from concrete.
Different uses of the lifting tools are also possible. Thus, although the lifting tools have been described in connection with wind turbine tower sections, they may also be used to handle other wind turbine components having an end with bolt holes arranged in a circle. This is typically the case with wind turbine blades, for example.
In light of the above, the details of any particular embodiment should not be seen to necessarily limit the scope of the claims below.

Claims

A lifting tool (12) for handling wind turbine tower sections (14) that each have an end with a flange (22) extending along a radius of curvature and bolt holes (24) extending through the flange, the lifting tool comprising:
a bracket (30) having a base (34) and an adaptor hole (36) extending through the base;

characterized in that there is provided:
a plurality of inserts (32) configured to be selectively positioned and retained in and/or over the adaptor hole (36), including an insert having bolt holes (50) arranged along a first radius of curvature corresponding to the radius of curvature of the flange of a first tower section so that the bracket is configured to be bolted to the end of the first tower section, and an insert having bolt holes arranged along a second radius of curvature different than the first radius of curvature, whereby an insert can be selected according to the tower section to be lifted.
A lifting tool according to claim 1, wherein the bracket further includes at least two walls (38) extending upwardly from the base and a gripping element (60) extending between at least two of the walls.
A lifting tool according to claim 2, wherein the gripping element (60) comprises a pin (62) coupled to first and second walls and a sleeve (64) rotatably supported by the pin between the first and second walls.
A lifting tool according to any of the preceding claims, wherein the bracket (30) comprises a first material having a first density and the insert comprises a second material having a second density less than the first density.
A lifting tool according to claim 4, wherein the bracket (30) comprises steel or iron and the inserts comprise aluminum.
A system (10) for handling one or more wind turbine tower sections that each have an end with a flange extending along a radius of curvature and bolt holes extending through the flange, the system comprising:
first (12a) and second (12b) lifting tools according to any of the preceding claims.
A system according to claim 6, further comprising:
a support member (16) to which the first and second lifting tools are coupled.
A system according to claim 7, wherein the support member (16) has an adjustable length between the first and second lifting tools.
A system according to claim 8, wherein the support member (16) comprises telescopic tubes.
A method for handling wind turbine tower sections that each have an end with a flange extending along a radius of curvature and bolt holes extending through the flange, the method comprising:
providing a lifting tool (12) according to any of claims 1-5;

coupling the lifting tool to a first tower section by:
selecting from the plurality of inserts an insert (32) with a radius of curvature corresponding to the radius of curvature of the flange (22) of the first tower section;

positioning the base (34) of the lifting tool over the flange of the first tower section;

positioning and retaining the insert of the lifting tool in and/or over the adaptor hole (36) of the base; and

securing the base to the end of the first tower section by bolting the insert to the flange; and

lifting the first tower section with the lifting tool.
A method according to claim 10, wherein lifting the first tower section with the lifting tool comprises:
coupling slings (66) to the lifting tool; and

lifting the slings with a crane.
A method according to claim 11, further comprising:
removing the lifting tool (12) from the first tower section;

selecting an insert (32) with a radius of curvature corresponding to the radius of curvature of the flange of a second tower section;

coupling the lifting tool (12) to the second tower section by:
positioning the base (34) of the lifting tool over the flange of the section tower section;

positioning and retaining the insert selected for the second tower section in and/or over the adaptor hole of the base; and

securing the base to the end of the second tower section by bolting the insert to the flange; and

lifting the second tower section with the lifting tool.
A method according to any of claims 10 to 12, wherein first (12a) and second (12b) lifting tools are provided and coupled to the first tower section at different locations along the flange thereof, and further wherein the first tower section is lifted with the first and second lifting tools.
A method according to claim 13, further comprising:
adjusting the length of a support member (16) configured to extend between the first and second lifting tools; and

coupling the support member (16) to the first and second lifting tools.