WO2023095002A1

WO2023095002A1 - Apparatus for assembling wind turbines and method therefor

Info

Publication number: WO2023095002A1
Application number: PCT/IB2022/061310
Authority: WO
Inventors: Gregory John Neighbours
Original assignee: Gregory John Neighbours
Priority date: 2021-11-23
Filing date: 2022-11-23
Publication date: 2023-06-01

Abstract

The present invention relates to a method and apparatus for assembling a tower from an assembly of multiple pre-cast concrete tubes, wherein a climbing rig and superstructure are together assembled atop a base tube atop a foundation of said tower, the climbing rig comprising a jack arrangement allowing the rig to climb the tower, such that a superstructure on top of the rig comprising a lifting system can be used, in concert with the climbing rig, to assemble said tubes to form said tower in a sequential manner as the superstructure and rig together climb to or towards a notional top of said tower during said assembly thereof.

Description

APPARATUS FOR ASSEMBLING WIND TURBINES AND METHOD THEREFOR

The present invention relates to an apparatus for assembling wind turbines and method therefor. More particularly but not exclusively it relates to a superstructure to sit atop a climbing rig that facilitates the assembly of a wind turbine from precast tubes. The superstructure may be capable of lifting and locating a nacelle, hub and blades and then lowering itself to the ground.

BACKGROUND

The present invention relates to the construction of tower structures and to related apparatus, methods, procedures and the like applicable thereto. Tower structures can be manufactured by a number of techniques.

A tower structure of interest to us includes those tower structures that can be used to support wind turbine nacelles. These generally are of a form with a circular exterior surface when viewed through a horizontal section but with a reduction in the diameter of that circular exterior surface as the tower gets higher.

The present invention recognises that there may be instances where a tower made from reinforced concrete, pre or post tensioned, and may be used as an alternative to structures normally used for such wind turbine towers. The present invention also appreciates that techniques applicable to such towers for wind turbines may equally be applicable to towers for other purposes whether convergent on its sides or not.

It is therefore an object of the present invention to provide at least one method of construction and related systems that lend themselves to the erection of a tower having a reinforced concrete wall that can be used to support the nacelle of a wind turbine, where the apparatus may be of a jump forming climbing rig.

It is an alternative and further object of the present invention to provide an apparatus which is able to be used, and procedures of its use, to construct a wind turbine tower, or which at least provides the public with a useful choice. For the purpose of this specification, where method steps are described in sequence, the sequence does not necessarily mean that the steps are to be chronologically ordered in that sequence, unless there is no other logical manner of interpreting the sequence.

BRIEF DESCRIPTION OF THE INVENTION

In a first aspect the present invention may be said to broadly consist in a method of assembling a tower from an assembly of multiple pre-cast concrete tubes utilising a climbing rig and superstructure, the method comprising the steps of: a. providing or assembling a base tube atop a foundation of said tower; b. providing a climbing rig arranged to be radially extending substantially around the circumference of said base tube of said tower, the climbing rig comprising multiple feet to engage the tower and a jack arrangement allowing the rig to climb the tower; c. providing a superstructure on top of the rig, the superstructure comprising a lifting system comprising girders preferably extending orthogonally from the tower's elongate axis and a winch tra nslationally connected thereto to allow the lifting system to raise and translate objects from outside of the footprint of the tower to within or partially within the footprint of the tower; d. using said lifting system to lift a pre-cast concrete tube onto the base tube of said to-be-assembled tower; e. using said rig to climb said to-be-assembled tower before lifting another precast concrete tube thereatop; f. repeating step e) such that the superstructure and rig together in concert assemble said pre-cast concrete tubes to form said tower in a sequential manner, the superstructure and rig together climbing to or towards a notional top of said tower during said assembly thereof until all the pre-cast concrete tubes of the tower are assembled to form said tower.

In one embodiment, the method comprises the step of providing a counterbalance arrangement operatively connected to or near the superstructure to provide a counterbalance to at least part of the loads imparted upon the superstructure, rig and/or tower during assembly of the tower. In one embodiment, the method comprises the step of configuring the counterbalance provided by the counterbalance arrangement based on the loads imparted upon the superstructure, rig and/or tower during assembly of the tower.

In one embodiment, the step of configuring the counterbalance provided by the counterbalance arrangement comprises providing substantially no counterbalance during movement of the superstructure and rig along the height of the tower.

In one embodiment, the method comprises the step of at least partially dislocating one or more radial segments of the climbing rig to provide clearance for movement of a nacelle, hub and/or blade(s) of the tower through or partially through the location where said segment was.

In one embodiment, wherein the method comprises the step of coupling the feet to the tower prior to at least partially dislocating the one or more radial segments of the climbing rig.

In one embodiment, the step of at least partially dislocating one or more radial segments of the climbing rig comprises the step of pivoting at least one segment relative an adjacent segment to swing said pivoted segment at least partially from the location where said pivoted segment was.

In one embodiment, the method comprises the step of using said lifting system to lift said nacelle, hub and/or blade(s) of the tower onto the top-most pre-cast concrete tube of the tower.

In one embodiment, the method comprises the step of the superstructure and rig together descending the tower to or near the foundation of said tower.

In one embodiment, the lifting system comprises braces to support the distal ends of the girders at a location close to a periphery of the climbing rig, and the method comprises the step of moving the one end of the braces to a location closer to the centre (elongate axis) of the tower.

In one embodiment, the method comprises the step of the lifting systems lowering down parts (such as a segment, the braces, a stairwell, a platform etc.) of the superstructure or rig prior to the rig climbing down the tower.

In another aspect, the invention may be said to broadly consist in an apparatus for assembling a tower from an assembly of multiple pre-cast concrete tubes; the apparatus comprising a. a climbing rig configured to radially extend and locate substantially about the circumference of the tower, the rig comprising multiple feet that engage with at least a portion of the tower during assembly thereof; and a jacking arrangement allowing the rig to climb up and down the tower, and b. a superstructure supported by the rig and comprising a lifting system comprising i. two parallel and spaced apart elongate girders at the same height extending orthogonal a central axis of the tower, ii. a transverse trolley arranged to translate along at least part of the length of the girders, the trolley comprising at least one winch and associated lifting cable to allow the lifting system to lift and position the pre-cast concrete tubes to the top of the tower and towards the central axis thereof for formation of the tower, and c. a counterbalance arrangement operatively connected to or near the superstructure to provide a counterbalance to at least part of the loads imparted upon the apparatus and/or tower during assembly thereof.

In one embodiment, the counterbalance arrangement comprises tensioning means operatively connecting to or near the superstructure to a foundation of said tower.

In one embodiment, the tensioning means are tensioned by means of winches provided at where the tensioning means operatively connect to or near the superstructure and/or winches provided at the foundation of said tower. In one embodiment, the winches are configured to determine the counterbalance provided by said tensioning means.

In one embodiment, the counterbalance arrangement comprises counterweights suspended from a location at or near the superstructure.

In one embodiment, the counterweights are suspended from a location at or near the superstructure by winches provided at said location.

In one embodiment, the counterweights are suspended from winches of a transverse trolley arranged to translate along at least part of the length of the girders.

In one embodiment, the position of the transverse trolley along the length of the girders is configured to determine the counterbalance provided by said counterweights.

In one embodiment, the climbing rig comprises one or more radial segments engageable and disengageable with an adjacent segment.

In one embodiment, one or more radial segments are at least partially dislocated from the rig by disengagement from one or more adjacent segments.

In one embodiment, one or more radial segments are at least partially dislocated from the rig by complete disengagement from one adjacent segment such that the partially dislocated segment may pivot about its connection to the other adjacent segment.

In one embodiment, the one or more radial segments are at least partially dislocatable from the rig to allow one or more of the nacelle, hub and/or blades of the tower to pass through the space previously occupied by the one or more at least partially dislocated segments.

In one embodiment, the girders are braced by respective braces at or towards distal ends of the girders.

In one embodiment, the braces connect the girders to the rig.

In one embodiment, each brace connects to the girder with a joint that allows rotation about more than one axis. In one embodiment, each brace has a rig end connected to the rig, and a girder end connected to the girder.

In one embodiment, the rig end in a first condition connects to a location radially further out than a second condition where the braces connect to a location on the rig closer to the central axis.

In one embodiment, the rig end attaches to the feet in the second condition.

In one embodiment, the superstructure defines a periphery above the rig.

In one embodiment, the girders are parallel to each other and are located at the periphery.

In the second condition the braces are angled towards the centre of the tower, or towards the exterior surface of the tower.

In one embodiment, the braces are removable.

In one embodiment, the braces are lowered to the ground by the lifting system.

In one embodiment, there are three or more segments.

In one embodiment, there are eight segments.

In one embodiment, in use the rig is fully supported by the tower.

In one embodiment, the superstructure is fully supported by the rig.

In one embodiment, in a complete condition when all segments are engaged to each other, the rig extends around the circumference of the tower.

In one embodiment, in a partial condition when at least one segment is disengaged, the rig extends around a portion of the circumference of the tower.

In one embodiment, the slots are formed as holes in the tubes.

In one embodiment, the feet tie to the slots.

In one embodiment, the feet can be tied and untied to the slots. In one embodiment, the feet are tied to the slots when the rig is in a partial condition.

In one embodiment, there are three blades to be installed equally spaced about the hub.

In one embodiment, the rig comprises;

• a higher subassembly adapted as a collar to selectively index to a zone where a tube is to be appended to the tower at abutments on an exterior of the tube, the higher subassembly supporting said superstructure,

• a lower subassembly adapted as a collar to selectively index to a zone of where a tube is to be appended to the tower at abutments on the exterior of the tube, and

• the jacking arrangement configured whereby (I), when the lower subassembly is zone indexed and the higher subassembly is not, the higher subassembly can be raised relative to the lower subassembly and the zone to a fresh indexing height and (II), when the higher subassembly is zone indexed and the lower subassembly is not, the lower subassembly can be raised to a fresh indexing height.

In one embodiment, the superstructure comprise at least four, preferably six, vertical trusses that define the periphery.

In one embodiment, the superstructure comprises a front opening to allow one or more selected from the tubes, hub, nacelle and blades to enter either or both of the footprint of the tower and the periphery.

In one embodiment, the superstructure comprises a rear opening opposite the front opening to allow the nacelle to extend out of the superstructure periphery.

In one embodiment, the vertical trusses directly or indirectly support the girders.

In one embodiment, the vertical trusses are symmetric about a vertical plane on line extending through the centre axis. Other aspects of the invention may become apparent from the following description which is given by way of example only and with reference to the accompanying drawings.

As used herein the term "and/or" means "and" or "or", or both.

As used herein "(s)" following a noun means the plural and/or singular forms of the noun.

The term "comprising" as used in this specification and claims means "consisting at least in part of". When interpreting statements in this specification and claims which include that term, the features, prefaced by that term in each statement, all need to be present but other features can also be present. Related terms such as "comprise" and "comprised" are to be interpreted in the same manner.

The term nacelle as used in this specification and claims means the nacelle housing comprising or not comprising any and all internals such as a generator, gearbox, other internals, attachment paraphernalia etc.

The entire disclosures of all applications, patents and publications, cited above and below, if any, are hereby incorporated by reference.

This invention may also be said broadly to consist in the parts, elements and features referred to or indicated in the specification of the application, individually or collectively, and any or all combinations of any two or more of said parts, elements or features, and where specific integers are mentioned herein which have known equivalents in the art to which this invention relates, such known equivalents are deemed to be incorporated herein as if individually set forth.)

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be described by way of example only and with reference to the drawings in which:

Figure 1A: shows a side view of an embodiment apparatus located on a base tube and foundation of a tower. Figure 1 B: shows a side view of the embodiment apparatus of Figure 1 A having assembled and climbed a height of the tower.

Figure 2: shows a perspective view of a climbing rig of an embodiment apparatus.

Figure 3: shows a perspective view of a climbing rig of an embodiment apparatus with the jacks extended.

Figure 4A: shows a detailed perspective view of a segment of the climbing rig.

Figure 4B: shows a detailed perspective view of a jack of the climbing rig.

Figure 5A: shows a side view of a segment engaged with an upper portion of a tower with the feet fully extending in.

Figure 5B: shows a side view of a segment engaged with a lower portion of a tower with the feet fully not fully extended in.

Figure 5C: shows a side view of a segment engaged with a tower utilising a wedge.

Figure 6: shows a perspective view of an embodiment apparatus utilising tension cables.

Figure 7 A: shows a perspective view of an embodiment apparatus with the braces in their second condition.

Figure 7B: shows a perspective view of an embodiment apparatus with the braces in their first condition.

Figure 8A: shows a near front view of the apparatus with two segments being dislocated.

Figure 8B: shows a near front view of the apparatus with the hub and blades being installed.

Figure 9: shows a perspective view of an embodiment apparatus utilising counterweights.

DETAILED DESCRIPTION

With reference to the above drawings, in which similar features are generally indicated by similar numerals, an apparatus according to a first aspect of the invention is generally indicated by the numeral 200.

The apparatus 200, as shown in Figure 1A, generally comprises of a climbing rig 3 and superstructure 20. The rig 3 is configured to climb a tower 1. The tower 1 may be formed using multiple hollow steel sections, or hollow concrete sections, also known as tubes 5. The tubes 5 may also be formwork which then has concrete cast inside in-situ.

Once the tower 1 is fully assembled, the apparatus 200 can lower itself to the ground, ready to be disassembled. Optionally, as the rig 3 climbs the tower 1 the superstructure may also assemble the tower 1 itself. This is achieved by either lifting in the tubes 5, or the formwork that is able to create the tubes 5. Herein, both the formwork and tubes themselves will be referred to as tubes 5.

The tower 1 may be supported by a ground-level foundation. The foundation may be pre-established. The present invention may be used in marine applications such as being supported on a seabed based foundation. The tower 1 can be used to support a wind turbine nacelle.

The tower 1 may generally be of a form with a circular exterior surface when viewed through a horizontal cross section and preferably with a reduction in the diameter of that circular exterior surface as the tower gets higher. The tower may be hollow and have an interior surface that is concentric the exterior surface. The tower, over at least a substantial part, may hence be of a substantially annular horizontal section.

Whilst the cross sectional profile of the tower defines a circular external surface; the external surface may be of another horizontal cross sectional profile. Likewise the internal surface may not be circular. They may, for example, be octagonal or other suitable polygonal form.

The tower is preferably tall, elongate, hollow and narrowing. The external shape may be frustoconical. It may be frustoconical up to a certain height and cylindrical to the top. Alternative shapes may be or may include a trumpet shaped, parabolic or other. In the preferred form the tower is tubular in horizontal section, tapered in over the height, and wider at the base reducing over height to a smaller diameter at the top.

The tower is preferably hollow to save on material costs, also allowing optional access via the internal cavity such as to access the nacelle, allow cabling etc. to and from the nacelle. The tower is assembled on site by assembling a plurality of tubes 5. The tower is formed in increments, by appending tubes 5 to each other in their elongate direction.

The process and apparatus utilise a climbing rig 3 that is placed/supported at the periphery of the first or lowermost tube 5 or base tube 53 of the tower that at that stage in the construction is the upper most tube of the tower, as shown in Figure 1. The rig 3 provides a collar assembly about the tube 5 and upwardly there from. As will be described later, the rig 3 is able to be jacked up to a higher position to facilitate the next tube of the tower 1 to be appended.

More preferably, the apparatus 200 can be set upon the foundation 54, and the apparatus 200 can lift in the base tube 53. The base tube 53 may be described in the industry as a kicker wall. The apparatus 200 may be bolted to the foundation 54 for initial support.

The rig 3 is able to move up the tower to re-position itself at a fresh indexing height 57 to allow new tubes 5 to be located in a place or a zone where a tube is to be appended 58, as indicated generally in Figure 1. The process is then repeated and a tower is created.

The climbing rig 3 as seen in Figure 2 comprises a collar assembly. The collar assembly is configured to be able to 'crawl' or climb up the periphery 7 (shown in Figure 1) of the tower 1 as the tower 1 is being constructed. The primary purpose of the climbing rig 3 is to facilitate the arrangement of precast concrete tapered tubes 5. During construction, the tubes 5 are appended onto the upper most section of the partially erected tower 1. In the beginning, a tube 5 is appended onto a base tube 53 that is supported by the ground or foundation 54.

The collar assembly has two subassemblies, a lower subassembly 4A and higher subassembly 4B, as shown in Figure 2. The higher subassembly 4B may comprise generally of an upper collar 16, connected with an intermediate collar 14 (by means of segments 17 shown in Figure 2, 3 and in particular Figure 4A).

The lower subassembly 4A is provided and adapted to be supported by a previously located tube 5 of the tower 1. It may comprise generally of a lower collar 13 movable away from an intermediate collar 14 of the rig 3, by means of jacks 10, as shown in Figure 3. The intermediate collar 14 may carry feet, like the feet 11 of the collar 13 described below to engage in slots 12 of the tower.

The upper collar 16 of the higher subassembly 4B may also be provided with a platform for handling the tubes 5 and other components. The work platform can support and provide workers access adjacent and to the region where the next tube will be located.

The higher subassembly 4B is provided and adapted so as to be able to locate with the next located tube 5 of the tower 1. The rig 3 may also support the superstructure 20, and is shown in Figure 2 with a plurality of trusses arranged therein, where work platforms, stairwells, cranes, winches, jack guides, jack motors and the like may be affixed to/supported by. For clarity, the rig 3 may, in other figures described herein, not be shown with such trusses and the like.

A jacking arrangement or jacks 10 is/are provided to act between the lower subassembly 4A and upper subassembly 4B, as shown in Figure 4B. In a climbing mode, the jacks 10 push off the lower subassembly 4A when the lower subassembly 4A is indexed with the partially erected tower to be able raise the upper subassembly 4B and pull up the lower subassembly 4A when the upper subassembly 4B is indexed with the partially erected tower. This may be seen when comparing the positions of the subassemblies 4A, 4B and collars 13, 14, 16 thereof, as shown in Figures 1 A, 1 B and 2 versus Figures 3, 6, 7A and 7B.

The lower assembly 4a (and lower level of the higher subassembly 4b) also comprises mechanisms to slide indexing members or feet 11 in and out of preformed abutments such as slots 12 (shown in Figure 1A and 1B) in the tube 5. The abutments 12 may be pockets or engagements or holes (through or blind). They may be abutments 12 that project out of the tower instead. The slots 12 are where the rig 3 is primarily supported by the tower and may carry the jacking loads back into the tower 1. These slots 12 are shown arranged circumferentially along the periphery 7 of the tower 1, and so slots 12 as referenced in this specification may refer to a plurality of slots 12 arranged in a row circumferentially along the periphery 7 of the tower (or tubes 5 thereof), as indicated in Figure 1A.

It should be noted that the figures show the slots 12 distanced vertically equidistantly apart from one another along the height of a tower 1 being constructed, as in Figure 1 B. Preferably, the slots 12 are spaced apart at distances equal to the jacking stroke of the rig 3 i.e., the maximum distance that the lower collar 13 extends from the lower subassembly 4a. As such, since the tubes 5 may themselves be of different heights, there may be different numbers of slots 12 arranged at each tube.

Those skilled in the art will be able to envisage a desired tower configuration and thus arrange the slots 12 about the tubes 5 thereof based on the given stroke of an embodiment apparatus 200 configuration (i.e., they may place slots 12 at 5 meter intervals along the height of the tower 1, based on a rig 3 having a 5 meter stroke, thus the first base tube 53, having a height of say 7 meters, may have two slots 12 arranged thereon, but a tube 5 nearer the top of the tower, being shorter in height, may only have one slot 12, once more as shown in Figure 1 B). The feet 11 (shown in detail in Figure 4A) may slide in and out using a variety of actuation means such as hydraulic, air, electric, as well as manual sliding into place. The feet 11 are of a length great enough so that they can extend to reach an aligned slot 12. With reference to the lower subassembly 4a , the feet 11 may extend from a collar 13 (shown in Figures 2 and 3, wherein in Figure 3 part of the rig 3 i.e., a radial segment 17 thereof, is hidden from view i.e., removed as will be described below, so as to better show the internal arrangement thereof and in particular, show the feet 11). The collar 13 is of constant diameter or size to be able to sit about the tower at all increments and the feet are long enough to extend to tower wall to be able to locate with aligned slots. Near the base of the tower, the feet 11 need only extend a short distance to the tower wall from the collar 13. As the tower grows in height and reduces in diameter, the feet 11 need to be able to extend a greater distance from the collar 13 to the tower wall - this is shown in Figure 5A and 5B comparatively.

The feet 11 may preferably engage flush against both top and bottom internal surfaces of slots 12, so as to counteract both tensile and compressive loads as well as turning/bending moments imparted upon the rig 3 during lifting activity. Vertical loads from the weight of the superstructure 20 and/or loads during lifting of tubes 5 may be imparted onto the upper subassembly 4B (i.e., to/at/between the upper and intermediate collars 14, 16). These vertical loads, or at least the self-weight of the superstructure 20, may then be transferred to the feet 11 (and surrounding truss/collar 13) and slots 12 when climbing of the rig 3 is occurring. Horizontal loads developed in particular while lifting are transferred into the tower 1 under construction by aa off-set or couple action resolved within the superstructure 20 where there is a bearing contact with the outer periphery 7 of the tower 1 and the superstructure 20.

Any load, moments and the like imparted on the superstructure 20 are preferably shared radially about the rig 3, or at least on radially opposing regions thereof, whether through the feet 11/slot 12 interfacing or otherwise.

Generally, reinforcement (whether external about the periphery 7 of the tower 1 under construction, or internal through the hollow interior of said tower 1) may be provided during operation of the apparatus 200, so as temporarily assist in bearing loads imposed on the tower 1 during construction thereof.

A person skilled in the art may pre-emptively plan which slots 12 (i.e., how far 'down' the assembled tubes 5 of the tower 1) to engage the feet 11 with, depending on expected loads, the stroke of the jacking arrangement 10 as described above, or other engineering considerations.

The rig 3 may be modular and comprised of parts or segments 17 that facilitate rapid assembly and disassembly as well as providing transportable modules. A segment 17 is shown in detail in Figure 4A. Preferably there are eight segments 17 that can easily be transported between sites and assembled onsite to complete the rig 3 ready for use, as shown in Figure 3. More or less segments 17 may be used. Quick-release pins or bolts may be utilised for the assembly and breakdown of the rig 3 in a rapid fashion.

Both collars 13 and 14 may be a trussed formation that when the segments are assembled is shaped like a doughnut or collar. A similar top collar 16 may also be provided. It is separated from the other collars by pillars or columns 18 forming part of the upper collar assembly 4b. This top collar may support the superstructure 20. The top collar 16 and the collar 14 move together.

The feet 11 preferably slide relative the collars in a radial direction. Preferably there is a foot 11 for each segment 17 of the two collars 13 and 14. The feet can slide both ways in a radial direction while engaging with the collar at or near one end as the segments/rig couple with the tower wall by seating at slots 12 that have been pre-located into the tube 5, as previously described. This allows full support of the rig 3 to be established from at the external sidewall of the tower and not the top ledge or internal wall of the tube 5. The rig 3 is sufficiently clear of the top ledge, so as to allow the next tube 5 to be placed thereat.

The assembled rig 3 and/or superstructure 20 may be provided as a skeletal frame and provides where needed, sufficiently large gaps, openings or gates between frame components to allow tubes 5 and any other construction components for forming the tower to be manoeuvred therethrough. In some embodiments, as discussed in further detail below, entire segments 17 may be disconnected and removed (by external means or even by way of the trolley 43 itself), to permit clearance for certain components, such as for a nacelle or blades of a wind turbine to be mounted atop the tower 1.

A wedge 19, as shown in Figure 5C may be utilised to allow the climbing rig to more stably climb up the tower. Further the wedge allows the collars or climbing rig 3 to travel directly vertical when climbing and not skew off-plumb. With the use of one or a number of wedges guides 19A are able to be guided up the tower 1 without having to move inwards as the tower 1 decrease in circumference. This allows the guides 19A to be kept at a constant distance during a jacking lift. This constant distance allows the rig to climb smoothly. At the next lift, the wedge can be moved upwards, and the guides 19A moved inwards to meet the wedge 19.The guides 19A preferably keep contact with the wedge or tower wall the entire lift. The guides 19A may be biased towards the wedge or tower wall. The guides may be sliding or rotatably engage with a wheel against the wedge or tower wall. Above the wedge 19, the feet 11 are able to engage with the slots 12. Preferably there are at least three guides 19A. The wedge may also be described as a tapered packer, as the wedge 19 is not wedging the rig 3 out, but packing the distance between the collars and the tower wall I external surface 7.

To lift in the tubes 5, a lifting system 40 is utilised. The lifting system 40 is part of the superstructure. The lifting system 40 comprises gantry crane like features to allow it to lift the building materials (tubes, nacelle, hub and blades etc) off the ground and translate them above and/or towards the tower 1 that is formed. The lifting system 40, as shown in Figure 6, comprises two orthogonal girders 22 extending horizontally atop a support arrangement 42 itself extending upwardly from the upper subassembly 4b of the rig 3. The two girders 22 act as a gantry to support a transverse trolley 43 that extends laterally between and atop the girders. The girders 22 are spaced parallel to each other and a distance apart from one another wider than the width of the tubes 5 to be lifted so no interference between the girders 22 and the tubes 5 can occur.

The support arrangement 42 is shown in Figure 6 as only extending partially circumferentially around the upper subassembly 4b of the rig 3. This is due to a gap 42X in said support arrangement 42 needing to be provided such that tubes 5 lifted by the lifting system 40 can travel therethrough to the place or a zone 58 where a tube is to be appended. In a similar manner described above in relation to the segments 17 of the rig 3, the support arrangement 42 may likewise be composed of separable and assemble modular segments to permit configuration of said gap 42X, as well as efficient modification/configuration, assembly, disassembly and transport of the support arrangement 42.

The trolley 43 can translate along the length of the girders 22. The trolley may support a winch arrangement or other winch like system to allow a translation of a lifting cable 41, so as to allow translation of any lifted goods along the length of the girders 22.

In Figure 6 the pulley arrangement is shown comprising two winches 44A atop the trolley 43. These winches 44A can translate laterally along the length of the trolley 43, so as to centre closer towards each other or further away, depending on the load the lifting cable 41 must endure. In some embodiments, both winches 44A may dispatch their own lifting cable, such that two lifting cables are provided to lift tubes 5 from multiple points. Those skilled in the art will appreciate many variations and configurations of winch, pulley or other lifting arrangements mountable to the trolley 43 for provision of lifting capabilities.

Typically, the trolley 43 will be positioned near fore ends 22A of the girders 22, so as to lift tubes 5 into the place or a zone 58 where a tube is to be appended, as shown and described above with reference to Figure 1. However, the trolley 43 may translate along the entire length of the girders 22 if need be.

Located near the aft ends 22B of the girders is a counterbalance arrangement 46 also shown comprising two winches 46A (or other suitable winch/pulley arrangement envisaged by a person skilled in the art). Routing through both these winches 46A of the counterbalance arrangement 46 are tensioning cables 47, the bottoms of which are tensioned to tie-downs 49 located at ground level that are mounted preferably to the foundation 54 of the tower 1. In some embodiments, these winches 46A may themselves be located at the ground level, as part of the tie-downs 49, with roller drums/idle winches or other suitable means of transferring tension of the cables 47 to the aft ends 22B of the girders 22 located at said aft ends 22B.

The counterbalance arrangement 46 creates a tension on the aft ends 22B of the girders 22, and more generally, a counterbalance to the lifting system 40 as a whole. It generally acts as a counterbalance to forces and moments exerted upon the lifting system 40 (and/or rig 3, apparatus 200, tower 1 as whole) created when lifting of a tube 5 is occurring, by means of the lifting cable(s) 41 and trolley 43.

More particularity, forces exerted upon the lifting system 40 are generally transferred to braces 23 (described in further detail below) that are appended beneath and connected to the fore ends 22A of the girders 22. Since the trolley 43 is generally located nearer said fore ends 22A during lifting, bending moments from the weight of a tube being lifted are exerted foremost upon the fore ends 22A of the girders. These forces/moments are thus transferred to the braces 23, or girder ends 23A thereof, which themselves transfer said forces/moments to a coupling point CP of the braces at where the rig ends 23B thereof connect to the rig 3, or more particularly, to the upper subassembly 4B of the rig 3.

In this manner, the tension cables 47 exert a tension upon the lifting system 40 which helps to counterbalance, or resolve, at least part of the bending moments and forces exerted at the coupling point CP during lifting of components by the lifting cables 41. In some instances, tubes 5 being lifted of sufficient weight may create uplift upon the girders 22 that necessitate further tension being provided by the counterbalance arrangement 46. The tension provided thereby may be calibrated by winches 46A atop the aft ends 22B of the girders 22 or pulleys/tensioning means located at the tie-downs 49, or any other means of tensioning the tension cables 47.

Equally, the tension or counterbalance provided by the counterbalance arrangement

46 may be appropriately released when lifting of tubes is not occurring. Releasing tension is necessary when the rig 3 is self-jacking (lifting or lowering itself) about the height of the tower 1, so as to avoid undue downward loads upon the rig 3 during its climbing.

Thus, appropriate control and actuation means will be provided for both the winches 44A of the trolley 43, as well as the winches 46A of the counterbalance arrangement 46, so as to calibrate lifting and counterbalance forces when required, and balance them as needed, or release them as needed. This can be achieved by motor control or many other means known to those skilled in the art of winch and lifting arrangements typically used in construction. The cables 47 may be pre-tensioned to determined/calculated loads or calibrated on the fly. Preferably, the cables 47 connect from the aft ends 22B of the girders 22 to the foundation 54 of the tower in a straight/substantially vertical/perpendicular line relative said foundation 54.

Winches 46A may instead be idle pulleys, with further tensioning winches instead provided at the foundation 54 (thus forming the tie downs 49) as described above. In this way, when tension is released from the tension cables 47 at the ground level (via said further tensioning winches provided at the foundation 54), the idle pulleys 46A may simply rotate to permit slack/translation of the tensioning cables 47 during movement of the rig 3 up and down the tower 1.

When the counterbalance arrangement 46 is in this released state, and thus lifting of significant loads is not occurring, any other moments or forces exerted upon the lifting system 40, through the coupling point CP (or rig ends 23B of the braces) are largely resolved or mitigated by the capturing of the feet 11 of the rig 3 into the slots 12 of the tower 1.

Those skilled in the art will appreciate a wide range of possible configurations for the counterbalance arrangement 46 that will achieve the function of counterbalancing the aft ends 22B of the girders 22, or otherwise counterbalancing different areas of the lifting system 40 or rig 3 as a whole, to resolve moments or forces exerted upon the coupling point CP (or rig ends 23B of the braces).

For instance, in addition, or in lieu of tensioning cables 47, further tensioning cables may be provided connecting the aft ends 22B of the girders 22 to the collar 16 of the upper subassembly 4B of the rig 3, or otherwise coupled to the outer periphery 7 of the tower 1, or even routed internally through completed sections of the tower 1, depending on various engineering desires, constraints or conditions.

In some instances, the tensioning cables 47 when not taught/tensioned, may sway in high-wind conditions. This can be an issue at taller heights if resonance is reached, which can cause high-frequency and high-amplitude swaying.

Thus, in some embodiments, as shown in Figure 9, the counterbalance arrangement 46 may instead comprise counterweights 47B. These counterweights 46A may hang off of/be suspended by cables 47C that are, like the embodiment counterbalance arrangement 46 described above, suspended off of the winches 46A of the counterbalance arrangement 46, near the aft ends 22B of the girders 22.

Much like the tensioning cables 47 of the counterbalance arrangement 46 embodiment described above, these counterweights 47B create a tension on the aft ends 22B of the girders 22, and more generally, a counterbalance to the lifting system 40 as a whole. This may help to counterbalance, or resolve, at least part of the bending moments and forces exerted at the coupling point CP during lifting of components by the lifting cables 41.

In such an embodiment, the winches 46A of the counterbalance arrangement 46 may be mounted atop a secondary trolley 43B, near the aft ends 22B of the girders 22, as shown in Figure 9. This allows said secondary trolley 43B, by virtue of its displacement along the top of girders 22, to change the counterbalance moment generated by the counterweights 47B, since the weight of said counterweights 47B, multiplied by the distance thereof from the moment centre (coupling point CP) determines the amount of counterbalance moment they exert.

The height at which the counterweights 47B are hung may be determined by the winches 46A, which may also be used to lower/lift the counterweights 47B as needed (for instance, to lower them down to the foundation and remove them, as needed to remove undue loads on the rig 3 when the apparatus 200 is climbing the tower 1).

Likewise, appropriate control and actuation means will be provided for the winches 46A of this embodiment counterbalance arrangement 46, so as to calibrate lifting and counterbalance forces when required, and balance them as needed, or release them as needed. This can be achieved by motor control or many other means known to those skilled in the art of winch and lifting arrangements typically used in construction.

Preferably the lifting system 40 comprises braces 23 as described above to support the distal ends 22A of the girders 22. The braces 23 direct the load supported by the trolley 43 down towards the rig 3 and tower 1. Each brace has a rig end 23B connected to the rig 3, and a girder end 23A connected to the girder 22.

The braces have two conditions; in a first condition (shown in Figure 7B) the rig ends 23B connect to a location radially further out than a second condition (shown in Figure 7A) where the braces 23 connect to a location on the rig closer to the central axis of the tower 1. The second condition reduces the moment formed between the tower 1 and the rig end 23B of the braces. Minimising the distance between a connection point of the rig ends 23B to the rig 3 and the tower 1 reduces twisting and moment forces, this is necessary when the lifting system is lifting high loads.

During the process of lifting the tubes 5, the braces 23 are connected to the rig 3, nearer more the rig periphery or collar 16. During the lifting of the lower more tubes of the tower, the tower 1 is generally quite close to the rig 3 periphery, i.e. the collar 16. As such, the load from the braces 23 does not create a large moment between the collar 16 and the tower 1 where the feet 11 are engaged to. As the rig 3 climbs the tower, the tubes reduce in diameter and the collar 16 is further away from the tower 1. The braces 23 can be moved to the second condition as shown in Figure 7A where the rig end of the braces connect to the feet 11 nearer more the tower 1, or at least further away from the collar 16 than the first condition.

The braces at their rig end 23B in the second condition are engaged to the feet 11. The feet 11 may also be tied to the tower 1 for a more secure connection during any lifting of larger loads.

The condition of the braces 23 may be configured conjointly with the configuration of the counterbalance arrangement 46 described above. In this manner, when lifting larger loads and thus the braces 23 placed in their second condition of Figure 7A, the tension of the tension cables 47 may be increased relative when the braces 23 are in their first condition of Figure 7B. It will be appreciated that changing the braces 23 from their first and second condition or vice versa may require lengthening or shortening of the braces 23. To that end, the braces 23 may comprise an internal threaded rod configuration or similar means to achieve that end. Further, the girder ends 23A of the braces 23A may connect to the girders 22 by way of articulate/universal ball joints or similar means to permit angular degrees of movement/rotation about more than one axis such that the braces 23 may be freely moved to their required positions when changing conditions. The rig ends 23B of the braces 23 may thus comprise disconnectable or releasable arrangements to permit their disconnection from the collar 16 or feet 11 when switching the braces 23 from their first and second condition or vice versa. Those skilled in the art may envisage other means of appropriately configuring the braces 23 or ends thereof to achieve these ends.

In some instances, the rig ends 23B of the braces 23 may be moved to various other locations on the collar 16 (including those of the first condition described above) to permit clearance of larger/bulky components of a tower 1 during lifting/installation thereof.

The rig 3 may in some embodiments, as described above in relation to Figure 3, comprise one or segments 17 that may radially dislocate from adjacent segments 17 that form the rig 3.

In some instances, as shown in Figures 8A and 8B, this segment 17 dislocation may occur as part of a method of lifting of larger/bulky components of a tower 1, such as the nacelle, hub and/or blades of a wind turbine to be mounted thereatop.

The method may thus comprise the step of dislocating one or more of the segments (a 'dislocatable segment 17A') to allow, for instance, the nacelle 1A to move through or partially through the location where the said dislocatable segment 17A was. The dislocatable segment 17A may also be dislocated prior to nacelle 1 A insertion. This gives more room to attach the dislocatable segment 17A to the lifting system 40 without interference from the nacelle 1A.

Dislocating the segments 17A allows for the hub and blades 1 B to move up to their installation location without interfering with the rig 3. Two dislocatable segments 17A. 17B are shown in Figure 8A. Where one dislocatable segment 17A is shown being removed from the rig to be subsequently lowered to the ground, and the other dislocatable segment 17B is shown pivoting from an adjacent segment 17 of the remaining rig 3.

A dislocatable segment 17A may be removed to allow the hub and a blade 1 B to be installed, whilst a second dislocatable segment 17B may be pivoted to allow the hub and blade 1 B to be rotated in a direction towards the pivoted second dislocatable segment 17B.

The pivoting dislocatable segment 17B may only be temporarily suspended/hinged away from the remainder of the rig 3 by means of tension members 17C, as shown in Figure 8A. These tension members 17C, or stays, or ties may comprise any suitable tension means known in the art, and may be used to displace the pivoting dislocatable segment 17B away from its default position within the rig 3, or even bring it back into said position, after the dislocation sequence has been completed. In some embodiments, temporary (rigid or non- rigid/tensioned) stays may be used to extend through the gap where a dislocated segment 17A was i.e., between the two segments 17 flanking that gap, to provide temporary reinforcement and rigidity to the rig 3 during lifting of the nacelle 1 A and/or hub and blades 1 B.

In some embodiments, the hub and blades 1 B do not require rotation upon installation, and thus, pivoting of the second dislocatable segment 17B may not be necessary.

In an alternative embodiment, a third pivoted dislocatable segment may be utilised on the other side of the removed dislocatable segment 17A.

How many dislocatable segments are removed or pivoted will depend on the geometry of the apparatus 200 and the components of the tower 1 being installed.

Preferably the feet 11 are tied to the tower 1 prior to dislocating the dislocatable segment. Where tying the feet 11 is actively engaging the feet 11 to the tower 1 by a mechanical means, so the feet 11 are able to withstand movement in a direction at least orthogonal to the central axis of the tower 1.

In one embodiment, dislocated segments 17A, 17B are relocated into their original position prior to the apparatus 200 lowering itself down the tower. This may occur once the blades are free from interference, i.e. once the apparatus 200 has already lowered a partial amount. It should be noted that the lifting system 40 is shown only schematically in Figure

8B, for clarity.

A brief overview of an example procedure of assembling a tower 1 is described below, where some steps are optional dependent on the tower 1 specifications.

1. Assembling the apparatus 200 about a base tube 53 located on a foundation 54.

2. Operating the lifting system 40 to sequentially lift in precast tubes 5 from the ground, into the place or a zone where a tube is to be appended 58, as indicated generally in Figure 1, and on top of the most recently placed tube 5, and assembling the tower 1 to its full height. a. During step 2, configuring the position of the braces 23 inwards and outwards from its first and second conditions, and also configuring the tension of the counterbalance arrangement 46, to balance the various loads, forces and moments imparted upon the tower 1 and/or superstructure 20. b. Simultaneously configuring the positions of the feet 11 and subassemblies 4A, 4B to permit the sequential climbing of the superstructure 20 as the tower 1 increases in height, optionally coupling or releasing the feet 11 from the slots 12 as/when required.

3. Optionally, once all tubes 5 are placed, reconfiguring parts of the support arrangement 42 or rig 3 to allow room for larger components of the tower 1, where their geometry requires it, such as: a. Dislocating segment(s) 17 for clearance of the nacelle 1 A or hub and blades 1 B (i.e., either entirely removing segment(s) 17 from the rig 3 by way of the lifting system 40, or merely temporarily pivoting away segment(s) 17), b. Lifting the nacelle 1A using the lifting system 40 to the top-most tube 5 and installing it thereon, c. Lifting the hub (with or without at least one blade) and attaching it to the nacelle 1A, and optionally, if further blades are required, lifting said further blades and attaching them to the hub (where segment pivoting or dislocation may be required when rotating the hub for installation of another blade).

4. Optionally, disconnecting and lowering braces 23 to the ground or moving the braces 23 so they do not hinder the lowering of the apparatus 200 once the tower 1 is fully assembled.

5. Optionally, releasing the tension of the counterbalance arrangement 46, or removing the cables 47 thereof in their entirety, to also permit lowering of the apparatus 200 once the tower 1 is fully assembled.

6. Climbing the rig 3 down the tower 1.

7. Disassembling the apparatus 200 so that its various subassemblies are ready to be assembled at the next site.

Various potential commercial advantages of using the methods and apparatus 200 described herein, compared with known self-supported tower or other crane/lifting arrangements include, for example:

• Much lower equipment cost, because the apparatus 200 removes the need for complex and large crane arrangements that need reach from the base of the tower all the way to above or near the top of the tower 1 height.

• Further, the apparatus 200 does not need support from the base upwards that is necessary for tall crane arrangements that may swing and move during high-elevation high-wind conditions typical of wind turbine sites.

• Reduced risk of down time caused by increased wind conditions typical of wind turbine sites. The sway frequency of the tower 1, apparatus 200 and the parts it is lifting will be the same. However, when using known tall crane arrangements, the masts or jibs thereof have their own sway frequency which may be different to that of the tower 1 or components being lifted. Thus, tall crane arrangements necessitate careful alignment of the crane, tower and components being lifted, resulting slow or stop production until lower wind conditions are resumed. • Increased production rate. Known tall self-supported cranes must climb themselves, requiring sequential additions of crane sections each time the tower gets taller, taking the crane out of tower building or turbine assembling activity and also requiring additional lifting apparatus to lift in the additional crane sections. By contrast, the apparatus 200 is largely fully assembled from the first tube 53 onwards, where climbing of the tower 1 during construction does not necessitate addition of further components of the apparatus 200 as the tower increases in height.

Where in the foregoing description reference has been made to elements or integers having known equivalents, then such equivalents are included as if they were individually set forth.

Although the invention has been described by way of example and with reference to particular embodiments, it is to be understood that modifications and/or improvements may be made without departing from the scope or spirit of the invention.

Claims

1. A method of assembling a tower from multiple pre-cast concrete tubes utilising a climbing rig and superstructure, the method comprising the steps of a. providing or assembling a base tube atop a foundation for said tower; b. providing a climbing rig and arranging it radially extending substantially around the circumference of said base tube of said tower, the climbing rig comprising multiple feet to engage the tower and a jack arrangement allowing the rig to self-climb the tower; c. providing a superstructure on top of the climbing rig, the superstructure comprising a lifting system comprising girders and a winch translationally connected thereto to allow the lifting system to raise and translate objects from outside of the footprint of the tower to within or partially within and above the footprint of the tower; d. using said lifting system to lift a pre-cast concrete tube onto the base tube of said to-be-assembled tower; e. using said rig to climb said to-be-assembled tower before lifting another precast concrete tube thereatop; f. repeating step e) such that the superstructure and rig together in concert assemble said pre-cast concrete tubes to form said tower in a sequential manner, the superstructure and rig together climbing to or towards a notional top of said tower during said assembly thereof until all the pre-cast concrete tubes of the tower are assembled to form said tower.

2. The method as claimed in claim 1, wherein the method comprises the step of providing a counterbalance arrangement operatively connected to or near the superstructure to provide a counterbalance to at least part of the loads imparted upon the superstructure, rig and/or tower during assembly of the tower.

3. The method as claimed in claim 2, wherein the method comprises the step of configuring the counterbalance provided by the counterbalance arrangement based on the loads imparted upon the superstructure, rig and/or tower during assembly of the tower.

26 The method as claimed in claim 3, wherein the step of configuring the counterbalance provided by the counterbalance arrangement comprises providing substantially no counterbalance during movement of the superstructure and rig along the height of the tower. The method as claimed in any one of the preceding claims, wherein the method comprises the step of at least partially dislocating one or more radial segments of the climbing rig to provide clearance for movement of a nacelle, hub and/or blade(s) of the tower through or partially through the location where said segment was. The method as claimed in claim 5, wherein the method comprises the step of coupling the feet to the tower prior to at least partially dislocating the one or more radial segments of the climbing rig. The method as claimed in claim 5 or claim 6, wherein the step of at least partially dislocating one or more radial segments of the climbing rig comprises the step of pivoting at least one segment relative an adjacent segment to swing said pivoted segment at least partially from the location where said pivoted segment was. The method as claimed in any one of claims 5 to 7, wherein the method comprises the step of using said lifting system to lift said nacelle, hub and/or blade(s) of the tower onto the top-most pre-cast concrete tube of the tower. The method as claimed in any one of the preceding claims, wherein the method comprises the step of the superstructure and rig together descending the tower to or near the foundation of said tower. An apparatus for assembling a tower from an assembly of multiple pre-cast concrete tubes; the apparatus comprising a. a climbing rig configured to radially extend and locate substantially about the circumference of the tower, the rig comprising multiple feet that engage with at least a portion of the tower during assembly thereof; and a jacking arrangement allowing the rig to self-climb up and down the tower, and b. a superstructure supported by the rig and comprising a lifting system comprising i. two parallel and spaced apart elongate girders at the same height extending orthogonal a central axis of the tower, ii. a transverse trolley arranged to translate along at least part of the length of the girders, the trolley comprising at least one winch and associated lifting cable to allow the lifting system to lift and position the pre-cast concrete tubes to the top of the tower and towards the central axis thereof for formation of the tower, and c. a counterbalance arrangement operatively connected to or near the superstructure to provide a counterbalance to at least part of the loads imparted upon the apparatus and/or tower during assembly thereof. The apparatus of claim 10, wherein the counterbalance arrangement comprises tensioning means operatively connecting to or near the superstructure to a foundation of said tower. The apparatus of claim 11, wherein the tensioning means are tensioned by means of winches provided at where the tensioning means operatively connect to or near the superstructure and/or winches provided at the foundation of said tower. The apparatus of claim 12, wherein the winches are configured to determine the counterbalance provided by said tensioning means. The apparatus of claim 10, wherein the counterbalance arrangement comprises counterweights suspended from a location at or near the superstructure. The apparatus of claim 14, wherein the counterweights are suspended from a location at or near the superstructure by winches provided at said location. The apparatus of claim 14, wherein the counterweights are suspended from winches of a transverse trolley arranged to translate along at least part of the length of the girders. The apparatus of claim 16, wherein the position of the transverse trolley along the length of the girders is configured to determine the counterbalance provided by said counterweights. The apparatus as claimed in any one of claims 10 to 17, wherein the climbing rig comprises one or more radial segments engageable and disengageable with an adjacent segment. The apparatus as claimed in claim 18, wherein one or more radial segments are at least partially dislocated from the rig by disengagement from one or more adjacent segments. The apparatus as claimed in claim 19, wherein one or more radial segments are at least partially dislocated from the rig by complete disengagement from one adjacent segment such that the partially dislocated segment may pivot about its connection to the other adjacent segment. The apparatus as claimed in any one of claims 18 to 20, wherein the one or more radial segments are at least partially dislocatable from the rig to allow one or more of the nacelle, hub and/or blades of the tower to pass through the space previously occupied by the one or more at least partially dislocated segments.

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