WO2023117018A1 - Cradle - Google Patents

Cradle Download PDF

Info

Publication number
WO2023117018A1
WO2023117018A1 PCT/DK2022/050300 DK2022050300W WO2023117018A1 WO 2023117018 A1 WO2023117018 A1 WO 2023117018A1 DK 2022050300 W DK2022050300 W DK 2022050300W WO 2023117018 A1 WO2023117018 A1 WO 2023117018A1
Authority
WO
WIPO (PCT)
Prior art keywords
pads
lifting
cradle
blade
resilient
Prior art date
Application number
PCT/DK2022/050300
Other languages
French (fr)
Inventor
Carsten SOMMER
Original Assignee
Dansk Gummi Industri A/S
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Dansk Gummi Industri A/S filed Critical Dansk Gummi Industri A/S
Publication of WO2023117018A1 publication Critical patent/WO2023117018A1/en

Links

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F03—MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
    • F03D—WIND MOTORS
    • F03D13/00—Assembly, mounting or commissioning of wind motors; Arrangements specially adapted for transporting wind motor components
    • F03D13/10—Assembly of wind motors; Arrangements for erecting wind motors
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F03—MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
    • F03D—WIND MOTORS
    • F03D13/00—Assembly, mounting or commissioning of wind motors; Arrangements specially adapted for transporting wind motor components
    • F03D13/40—Arrangements or methods specially adapted for transporting wind motor components
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B66—HOISTING; LIFTING; HAULING
    • B66C—CRANES; LOAD-ENGAGING ELEMENTS OR DEVICES FOR CRANES, CAPSTANS, WINCHES, OR TACKLES
    • B66C1/00—Load-engaging elements or devices attached to lifting or lowering gear of cranes or adapted for connection therewith for transmitting lifting forces to articles or groups of articles
    • B66C1/10—Load-engaging elements or devices attached to lifting or lowering gear of cranes or adapted for connection therewith for transmitting lifting forces to articles or groups of articles by mechanical means
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B66—HOISTING; LIFTING; HAULING
    • B66C—CRANES; LOAD-ENGAGING ELEMENTS OR DEVICES FOR CRANES, CAPSTANS, WINCHES, OR TACKLES
    • B66C1/00—Load-engaging elements or devices attached to lifting or lowering gear of cranes or adapted for connection therewith for transmitting lifting forces to articles or groups of articles
    • B66C1/10—Load-engaging elements or devices attached to lifting or lowering gear of cranes or adapted for connection therewith for transmitting lifting forces to articles or groups of articles by mechanical means
    • B66C1/108—Load-engaging elements or devices attached to lifting or lowering gear of cranes or adapted for connection therewith for transmitting lifting forces to articles or groups of articles by mechanical means for lifting parts of wind turbines
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B66—HOISTING; LIFTING; HAULING
    • B66C—CRANES; LOAD-ENGAGING ELEMENTS OR DEVICES FOR CRANES, CAPSTANS, WINCHES, OR TACKLES
    • B66C1/00—Load-engaging elements or devices attached to lifting or lowering gear of cranes or adapted for connection therewith for transmitting lifting forces to articles or groups of articles
    • B66C1/10—Load-engaging elements or devices attached to lifting or lowering gear of cranes or adapted for connection therewith for transmitting lifting forces to articles or groups of articles by mechanical means
    • B66C1/12—Slings comprising chains, wires, ropes, or bands; Nets
    • B66C1/16—Slings with load-engaging platforms or frameworks
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
    • F05B—INDEXING SCHEME RELATING TO WIND, SPRING, WEIGHT, INERTIA OR LIKE MOTORS, TO MACHINES OR ENGINES FOR LIQUIDS COVERED BY SUBCLASSES F03B, F03D AND F03G
    • F05B2230/00—Manufacture
    • F05B2230/60—Assembly methods
    • F05B2230/61—Assembly methods using auxiliary equipment for lifting or holding
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E10/00—Energy generation through renewable energy sources
    • Y02E10/70—Wind energy
    • Y02E10/72—Wind turbines with rotation axis in wind direction

Definitions

  • the present invention relates to a lifting cradle suitable to lift and support a wind turbine blade, as well as a method of using such a lifting cradle.
  • the present invention presents a versatile and inventive lifting cradle which due to its construction both provides a very adaptive and deformable support which comes into to contact with the blade itself and at the same time provides a very rigid and adjustable cradle to which the straps of the crane may be attached.
  • the invention addresses this by providing a lifting cradle suitable to lift and support a wind turbine blade, where said cradle comprises a stiff carrying base, said carrying base having an underside and an upper side, where guide means are provided in or along the underside, said guide means is suitable to slidingly hold a lifting strap or sling, and where on the upper side, two or more resilient pads are arranged where said pads are deformable when exposed to a load, and a further resilient pad being less deformable than the two other pads, where all pads have a support surface.
  • the support for the lifting blade itself is advantageously constituted by three separate support means arranged on the upper side of the lifting cradle.
  • wind turbine blades to which the present invention is directed have a length of 60 meters and upwards, and in order to provide sufficient strength and stiffness for the blade a longitudinal inner bulkhead is provided.
  • more bulkheads and more strengthening structures inside the blade may also be provided as needed.
  • at least one bulkhead is provided in the longitudinal direction of the blade where the bulkhead is positioned where the cross-section of the blade orthogonal to the longitudinal direction of the blade is at its largest. In this manner, by positioning the blade such that the bulkhead is superposed the resilient pad being less deformable than the other resilient pads, the main load is carried by this support pad.
  • the adjacent resilient pads may be more resilient such that as the blade settles onto the pad being less resilient the adjacent pads will deform due to the load and thereby create support surfaces for the blade distributing the load and this manner provide a gentle support and carrying of the blade as the cradle is lifted.
  • the carrying base is made from a polymer material optionally reinforced with fibres, glass or the like, and provided with at least one profile embedded in the underside, said profile being dimensioned to accommodate the lifting strap or sling, where the profile is made from steel, carbon or glass fiber reinforced resin.
  • the carrying base needs to be relatively stiff in order to maintain the lifting straps away from the blade itself, but the weight distribution of the blade in the resilient pads arranged on the carrying base will also support in making the overall lifting cradle appear relatively stiff due to the distribution of load from the blade across the deformable resilient pads.
  • the side of the profile which is intended to be in contact with the lifting strap or sling has a low friction surface, or is provided with a low friction treatment. In this manner the repositioning of the lifting cradle once the blade is positioned inside the lifting cradle and the lift has commenced may be carried out in an easier manner due to the low friction.
  • the carrying base is made from steel profiles , said steel profiles being bent into a U-shape, where a wind turbine blade may be fit-ted inside the U and a number of guide rollers are arranged along the underside and in either end of the U for guiding the lifting strap or sling.
  • This construction provides a number of other advantages than the embodiment described above in that a substantially rigid carrying base is provided whereby it becomes possible to distance the resilient pads more along the carrying structure.
  • the carrying base is in this embodiment provided with guide rollers such that very low friction interface between the lifting strap or sling is provided whereby the repositioning of the lifting cradle once the blade is loaded onto the lifting cradle may easily be carried out.
  • the at least one of the two or more resilient pads is made from polyurethane, and where a plurality of apertures are arranged through the pads, such that the resiliency of the pad is designed for a particular load or load distribution, and where the resiliency in one pad may vary across the pad’s support surface.
  • the resilient pads In order to create an optimum support for the blade once it is positioned in the cradle it is advantageous to be able to design the resilient pads such that they deform relative to the contour of the wind turbine blade being intended to be lifted by the lifting cradle.
  • this input may be used in a design program assimilating the impact of the blade on the resilient pads.
  • the resilient pads During and through this simulation it becomes possible to dimension the resilient pads to be more or less deformable in zones whereby a substantially continuous and even support of the wind turbine blade once it is positioned in the cradle will be obtained by varying the stiffness/resiliency of the resilient support pads.
  • the variation in resiliency may for example be obtained by casting or drilling holes into the resilient pad, typically parallel to the extend of the blade where the pattern of these apertures may be varied in order to accomplish the variation in resiliency being the output from the simulation program as discussed above.
  • the support pads will be manufactured from polyurethane and may either extruded or cast into suitable molds such that they are custom-made for the particular task to which they are to be used.
  • the carrying base or the plate comprises first engagement means at the upper side and at least one of the resilient pads comprises second engagement means adapted to releasably interlock with the first engagement means.
  • the resilient pad(s) are releasably arranged on the upper side of the base or on the plate and the cradle can be adjusted to the size and weight of the load to be carried.
  • the invention is also directed to a method of using a lifting cradle according to the present invention where the method foresees that the cradle is positioned on a flat surface, and a wind turbine blade is then lowered onto the cradle such that a main bulkhead inside the wind turbine blade or in the absence of a bulkhead the greatest cross-section measurement of the blade orthogonal to the longitudinal extend of the blade is positioned on the resilient pad being less deformable than the two other pads, and where a lifting strap or sling is positioned in the guide means provided in or along the underside of the cradle either before the blade is lowered onto the cradle or after the blade is positioned in the cradle; lift is then applied to the lifting strap or sling, such that the cradle and blade are elevated from the surface; and optionally the blade’s position is adjusted by letting the blade and cradle slide relative to the lifting strap or sling.
  • the invention is also directed to a kit for any one of the described embodiments of the lifting cradle.
  • the kit comprises the stiff carrying base having an underside and an upper side, where guide means are provided in or along the underside, said guide means are suitable to slidingly hold a lifting strap or sling.
  • the kit furthermore comprises two or more resilient pads adapted to be arranged on the upper side of the base, where said pads are deformable when exposed to a load.
  • the kit also comprises at least one further resilient pad adapted to be arranged on the upper side of the base.
  • the further resilient pad is less deformable than the two or more other resilient pads.
  • the base comprising first engagement means and at least one of the resilient pads comprises second engagement means adapted to interlock with first engagement means.
  • the kit may comprise the plate with the first engagement means integrated therein instead of in the base.
  • the plate is adapted to be arranged on the upper side of the carrying case.
  • Figure 1 illustrates an embodiment of the invention where the lifting cradle is suspended by a lifting strap.
  • Figure 2 illustrates an embodiment of the invention where the stiff carrying base is constructed by assembling steel profiles.
  • Figure 3 illustrates a similar lifting cradle where a blade has been positioned on top of the resilient pads.
  • Figure 4 illustrates an embodiment of a kit for the lifting cradle with engagement means in the form of pins and holes.
  • Figure 5 illustrates an embodiment of the lifting cradle with engagement means in the form of teeth and racks.
  • FIG 1 is illustrated an embodiment of the invention where the lifting cradle 10 is suspended by a lifting strap 20.
  • a blade from a wind turbine illustrated by only a section of said blade 30.
  • the lifting cradle 10 comprises a stiff carrying case 12.
  • the carrying case is on an underside 14 provided with guide means 16.
  • the guide means 16 are in this embodiment in the shape of shallow grooves or indentations in the underside 14 where the shallow grooves are dimensioned such that they may accommodate the lifting strap 20.
  • the grooves may be foreseen with a steel reinforcement such that tear and wear do not impact on the stiff carrying base 12 as such.
  • the shallow grooves 16 may furthermore be treated with a friction reducing compound such as for example Teflon or the like in order to be able to reposition the cradle 10 once the blade 30 has been arranged as indicated.
  • the stiff carrying base On the upper side 18 of the stiff carrying base are positioned in this embodiment three separate resilient pads 22, 24, 26.
  • the resiliency of the different resilient pads 22, 24, 26 is designed such that the wind turbine blade 30 is supported optimally such that a safe and stable support is provided and at the same time the risk of damaging the surface of the wind turbine blade is minimized.
  • the resilient pad 22 has a contour substantially corresponding to the contour of the part of the blade which is intended to be supported at this particular position.
  • the resiliency of the resilient pad 22 allows the pad 22 to be deformed as the load is imparted to the pad 22 such that the resilient pad will deform thereby optimizing the support of the wind turbine blade.
  • the other resilient pad 26 has more or less the same function, but due to the position in which it is designed to support the wind turbine blade the resilient character of this resilient pad may be different from the larger resilient pad 22.
  • the resiliency of both pads 22, 26 may be designed by simulating the load from a particular wind turbine blade on the support and by providing apertures 41 in the material of the resilient pads 22, 26 the compressibility, deformation and overall resiliency of the pads 22, 26 may be altered and designed for the specific purpose.
  • the further resilient pad 24 will normally only have little resiliency as it is positioned superposed a bulkhead 32 indicated by dashed lines.
  • the bulkhead is an interior feature inside the wind turbine blade 30 and will typically be arranged approximately where the cross-section has the largest dimension as indicated by the illustrated bulkhead 32 in dashed lines.
  • the support in the lifting cradle in this position is both resilient and very firm such that a safe and reliable support may be created for the entire blade.
  • the resilient pad 24 will more or less support a substantial part of the load from the wind turbine blade whereas the two more deformable resilient pads 22, 26 due to the deformation will support and hold the blade in a reliable position.
  • the resilient pads may for example be bolted to the carrying case, alternatively they may be fixed by adhesive means or when the resilient pads are made from a polyurethane foam they may be cast in place, and due to the characteristics of the polyurethane foam they might adhere simply by the material characteristics.
  • Multiple first or second engagement means may be provided to facilitate multiple positions of one or more of the pads on the carrying case thereby achieving that the pads may be easily repositioned or achieve to adjust the number of resilient pads arranged on the carrying case for an adjustable lifting cradle.
  • the grooves 16 may also be formed by casting steel profiles into the stiff carrying base material, particularly when the stiff carrying base material is a castable material, such as for example a polyurethane or a fibre -reinforced resin. Naturally, also other materials may be contemplated in order to manufacture a suitable stiff carrying base.
  • the stiff carrying base is constructed by assembling steel profiles.
  • the steel profiles 12 are assembled into a lifting cradle generally having a U- shape meaning that there is a central flat portion 52 and in either end of this flat portion 52 are provided two upstanding sections 54, 56.
  • a number of rollers 58 are provided such that a lifting strap (not illustrated) will be guided around the underside of the stiff carrying base 12 not coming into contact with the blade as such.
  • the stiff carrying base 12 is furthermore provided with a plate 60 on an upper side of the steel profiles 52. On top of the plate are arranged resilient pads in the same fashion as discussed above with reference to figure 1. In this manner the resilient pads 22, 24, 26 will be able to accommodate a wind turbine blade as discussed above with reference to figure 1. Naturally, the characteristics of the resilient pads may be determined as already discussed.
  • the resilient pads may comprise locking pins 74 to releasably interlock with holes 72 in the plate 60, such that the pads are releasably arranged on the plate for achieving an adjustable and modular cradle.
  • Exemplary embodiment comprising engagement means comprised in the plate 60 and in the resilient pads 22, 24, 26 are illustrated in figures 4 and 5.
  • the engagement means of the resilient pads are provided by locking pins 74 configured to interlock with holes 72 in the plate 60.
  • An alternative embodiment could be achieved by omitting the plate 60 and provide the holes in the carrying base.
  • the engagement means provided in the plate 60 are provided by toothed rack 82 interlocked with the engagement means of the resilient pad provided by locking teeth 84.
  • An alternative embodiment could be achieved by omitting the plate 60 and provide the toothed rack in the carrying base.
  • the stiff carrying base 12 is furthermore provided with wheels 62 such that the entire lifting cradle 10 easily may be positioned correctly relative to the blade or moved e.g. to storage.
  • FIG 3 is illustrated a similar lifting cradle 10 where a blade has been positioned on top of the resilient pads. As may be seen, the resilient pad 26 has been compressed due to the load of the blade 30 and as such the lifting cradle 10 is in a supporting mode where the weight of the blade 30 has been optimally distributed on the carrying surfaces of the resilient pads.
  • the stiff carrying base 12 is provided with brackets 66 in addition to the wheels 62 and stabilizing pegs 64 such that the carrying base will be stable when it is positioned on a flat surface. These brackets are dimensioned such that a forklift may engage and move the lifting cradle.
  • the resilient pads are dimensioned such that when the resilient pads 22, 26 are deformed due to the load from the blade as described above with reference to figure 3 these pads are selected such that they are suitable for the particular blade in question.
  • the lifting cradle is positioned underneath the blade such that the blade may be lowered onto the lifting cradle and arrive at a position for example as illustrated in figures 1 or 3.
  • a lifting strap or sling may be positioned around the underside of the lifting cradle in contact with the rollers as described above with reference to figures 2 and 3 or guided into the shallow grooves 16 illustrated and described with reference to figure 1.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Sustainable Development (AREA)
  • Sustainable Energy (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • General Engineering & Computer Science (AREA)
  • Wind Motors (AREA)

Abstract

Lifting cradle, suitable to lift and support a wind turbine blade, where said cradle comprises a stiff carrying base, said carrying base having an underside and an upper side, where guide means are provided in or along the underside, said guide means is suitable to slidingly hold a lifting strap or sling, and where on the upper side, two or more resilient pads are arranged where said pads are deformable when exposed to a load, and a further resilient pad being less deformable than the two other pads, where all pads have a support surface.

Description

Cradle
Field of the Invention
The present invention relates to a lifting cradle suitable to lift and support a wind turbine blade, as well as a method of using such a lifting cradle.
Background of the Invention
In the art a number of devices and methods have been used in order to handle particularly wind turbine blades or other similar very long flexible objects. As the size of the wind turbine blades steadily increases, new and more versatile handling means are required in order to be able to safely handle and lift the turbine blades, for example in connection with finishing work, loading and off-loading from truck or ships or the like and during the installation phase.
Object of the Invention
To this end the present invention presents a versatile and inventive lifting cradle which due to its construction both provides a very adaptive and deformable support which comes into to contact with the blade itself and at the same time provides a very rigid and adjustable cradle to which the straps of the crane may be attached.
Description of the Invention
The invention addresses this by providing a lifting cradle suitable to lift and support a wind turbine blade, where said cradle comprises a stiff carrying base, said carrying base having an underside and an upper side, where guide means are provided in or along the underside, said guide means is suitable to slidingly hold a lifting strap or sling, and where on the upper side, two or more resilient pads are arranged where said pads are deformable when exposed to a load, and a further resilient pad being less deformable than the two other pads, where all pads have a support surface. Particularly the feature of providing a substantially rigid carrying base in combination with a sliding surface in said carrying base such that the lifting strap may slide relative to the carrying base provides the opportunity that once the lifting process has begun it is possible to slightly adjust the angle of the cradle and thereby the position of a cradle relative to the lift such that the wind turbine blade may be lifted as intended.
If the lifting strap or sling was not able to slide relatively to the lifting cradle there is a risk that the lifting action would cause the blade to rotate slightly relative to its intended position whereby other support means, for example at the root of the blade may become unlodged or unstable. For these reasons the ability of the lifting strap or sling to slide relative to the lifting cradle is very important.
The support for the lifting blade itself is advantageously constituted by three separate support means arranged on the upper side of the lifting cradle. Typically, wind turbine blades to which the present invention is directed have a length of 60 meters and upwards, and in order to provide sufficient strength and stiffness for the blade a longitudinal inner bulkhead is provided. Naturally, more bulkheads and more strengthening structures inside the blade may also be provided as needed. However, it is typical that at least one bulkhead is provided in the longitudinal direction of the blade where the bulkhead is positioned where the cross-section of the blade orthogonal to the longitudinal direction of the blade is at its largest. In this manner, by positioning the blade such that the bulkhead is superposed the resilient pad being less deformable than the other resilient pads, the main load is carried by this support pad. The adjacent resilient pads may be more resilient such that as the blade settles onto the pad being less resilient the adjacent pads will deform due to the load and thereby create support surfaces for the blade distributing the load and this manner provide a gentle support and carrying of the blade as the cradle is lifted.
In a further advantageous embodiment of the invention the carrying base is made from a polymer material optionally reinforced with fibres, glass or the like, and provided with at least one profile embedded in the underside, said profile being dimensioned to accommodate the lifting strap or sling, where the profile is made from steel, carbon or glass fiber reinforced resin. The carrying base needs to be relatively stiff in order to maintain the lifting straps away from the blade itself, but the weight distribution of the blade in the resilient pads arranged on the carrying base will also support in making the overall lifting cradle appear relatively stiff due to the distribution of load from the blade across the deformable resilient pads.
In a further advantageous embodiment the side of the profile which is intended to be in contact with the lifting strap or sling has a low friction surface, or is provided with a low friction treatment. In this manner the repositioning of the lifting cradle once the blade is positioned inside the lifting cradle and the lift has commenced may be carried out in an easier manner due to the low friction.
In another embodiment of the invention the carrying base is made from steel profiles , said steel profiles being bent into a U-shape, where a wind turbine blade may be fit-ted inside the U and a number of guide rollers are arranged along the underside and in either end of the U for guiding the lifting strap or sling. This construction provides a number of other advantages than the embodiment described above in that a substantially rigid carrying base is provided whereby it becomes possible to distance the resilient pads more along the carrying structure. By further providing the carrying base with wheels as is foreseen in another embodiment of the invention positioning of the lifting cradle relative to the wind turbine blade is facilitated.
The carrying base is in this embodiment provided with guide rollers such that very low friction interface between the lifting strap or sling is provided whereby the repositioning of the lifting cradle once the blade is loaded onto the lifting cradle may easily be carried out.
In a further advantageous embodiment the at least one of the two or more resilient pads is made from polyurethane, and where a plurality of apertures are arranged through the pads, such that the resiliency of the pad is designed for a particular load or load distribution, and where the resiliency in one pad may vary across the pad’s support surface.
In order to create an optimum support for the blade once it is positioned in the cradle it is advantageous to be able to design the resilient pads such that they deform relative to the contour of the wind turbine blade being intended to be lifted by the lifting cradle. As the contour and weight distribution of the wind turbine blade is precisely known by the designer of the wind turbine blade this input may be used in a design program assimilating the impact of the blade on the resilient pads. During and through this simulation it becomes possible to dimension the resilient pads to be more or less deformable in zones whereby a substantially continuous and even support of the wind turbine blade once it is positioned in the cradle will be obtained by varying the stiffness/resiliency of the resilient support pads. The variation in resiliency may for example be obtained by casting or drilling holes into the resilient pad, typically parallel to the extend of the blade where the pattern of these apertures may be varied in order to accomplish the variation in resiliency being the output from the simulation program as discussed above.
Typically, the support pads will be manufactured from polyurethane and may either extruded or cast into suitable molds such that they are custom-made for the particular task to which they are to be used.
In one embodiment the carrying base or the plate comprises first engagement means at the upper side and at least one of the resilient pads comprises second engagement means adapted to releasably interlock with the first engagement means.
Hereby it is achieved that the resilient pad(s) are releasably arranged on the upper side of the base or on the plate and the cradle can be adjusted to the size and weight of the load to be carried.
The invention is also directed to a method of using a lifting cradle according to the present invention where the method foresees that the cradle is positioned on a flat surface, and a wind turbine blade is then lowered onto the cradle such that a main bulkhead inside the wind turbine blade or in the absence of a bulkhead the greatest cross-section measurement of the blade orthogonal to the longitudinal extend of the blade is positioned on the resilient pad being less deformable than the two other pads, and where a lifting strap or sling is positioned in the guide means provided in or along the underside of the cradle either before the blade is lowered onto the cradle or after the blade is positioned in the cradle; lift is then applied to the lifting strap or sling, such that the cradle and blade are elevated from the surface; and optionally the blade’s position is adjusted by letting the blade and cradle slide relative to the lifting strap or sling. By using the lifting cradle in this method all the advantageous features of the cradle may be utilized in order to accomplish a safe and customized lifting of a wind turbine blade.
The invention is also directed to a kit for any one of the described embodiments of the lifting cradle.
The kit comprises the stiff carrying base having an underside and an upper side, where guide means are provided in or along the underside, said guide means are suitable to slidingly hold a lifting strap or sling.
The kit furthermore comprises two or more resilient pads adapted to be arranged on the upper side of the base, where said pads are deformable when exposed to a load.
The kit also comprises at least one further resilient pad adapted to be arranged on the upper side of the base. The further resilient pad is less deformable than the two or more other resilient pads. The base comprising first engagement means and at least one of the resilient pads comprises second engagement means adapted to interlock with first engagement means.
In a further embodiment the kit may comprise the plate with the first engagement means integrated therein instead of in the base. The plate is adapted to be arranged on the upper side of the carrying case.
Description of the Drawing
The invention will now be explained with reference to the accompanying drawings wherein
Figure 1 illustrates an embodiment of the invention where the lifting cradle is suspended by a lifting strap.
Figure 2 illustrates an embodiment of the invention where the stiff carrying base is constructed by assembling steel profiles.
Figure 3 illustrates a similar lifting cradle where a blade has been positioned on top of the resilient pads. Figure 4 illustrates an embodiment of a kit for the lifting cradle with engagement means in the form of pins and holes.
Figure 5 illustrates an embodiment of the lifting cradle with engagement means in the form of teeth and racks.
Detailed Description of the Invention
In figure 1 is illustrated an embodiment of the invention where the lifting cradle 10 is suspended by a lifting strap 20. In the lifting cradle is arranged a blade from a wind turbine illustrated by only a section of said blade 30.
The lifting cradle 10 comprises a stiff carrying case 12. The carrying case is on an underside 14 provided with guide means 16. The guide means 16 are in this embodiment in the shape of shallow grooves or indentations in the underside 14 where the shallow grooves are dimensioned such that they may accommodate the lifting strap 20. The grooves may be foreseen with a steel reinforcement such that tear and wear do not impact on the stiff carrying base 12 as such. Furthermore, the shallow grooves 16 may furthermore be treated with a friction reducing compound such as for example Teflon or the like in order to be able to reposition the cradle 10 once the blade 30 has been arranged as indicated.
On the upper side 18 of the stiff carrying base are positioned in this embodiment three separate resilient pads 22, 24, 26. The resiliency of the different resilient pads 22, 24, 26 is designed such that the wind turbine blade 30 is supported optimally such that a safe and stable support is provided and at the same time the risk of damaging the surface of the wind turbine blade is minimized. For this reason, the resilient pad 22 has a contour substantially corresponding to the contour of the part of the blade which is intended to be supported at this particular position. Furthermore, the resiliency of the resilient pad 22 allows the pad 22 to be deformed as the load is imparted to the pad 22 such that the resilient pad will deform thereby optimizing the support of the wind turbine blade.
The other resilient pad 26 has more or less the same function, but due to the position in which it is designed to support the wind turbine blade the resilient character of this resilient pad may be different from the larger resilient pad 22. The resiliency of both pads 22, 26 may be designed by simulating the load from a particular wind turbine blade on the support and by providing apertures 41 in the material of the resilient pads 22, 26 the compressibility, deformation and overall resiliency of the pads 22, 26 may be altered and designed for the specific purpose.
The further resilient pad 24 will normally only have little resiliency as it is positioned superposed a bulkhead 32 indicated by dashed lines. The bulkhead is an interior feature inside the wind turbine blade 30 and will typically be arranged approximately where the cross-section has the largest dimension as indicated by the illustrated bulkhead 32 in dashed lines.
As a major part of the weight of the blade will be transmitted through this bulkhead it is important that the support in the lifting cradle in this position is both resilient and very firm such that a safe and reliable support may be created for the entire blade. In this manner the resilient pad 24 will more or less support a substantial part of the load from the wind turbine blade whereas the two more deformable resilient pads 22, 26 due to the deformation will support and hold the blade in a reliable position.
The resilient pads may for example be bolted to the carrying case, alternatively they may be fixed by adhesive means or when the resilient pads are made from a polyurethane foam they may be cast in place, and due to the characteristics of the polyurethane foam they might adhere simply by the material characteristics.
Multiple first or second engagement means may be provided to facilitate multiple positions of one or more of the pads on the carrying case thereby achieving that the pads may be easily repositioned or achieve to adjust the number of resilient pads arranged on the carrying case for an adjustable lifting cradle.
The grooves 16 may also be formed by casting steel profiles into the stiff carrying base material, particularly when the stiff carrying base material is a castable material, such as for example a polyurethane or a fibre -reinforced resin. Naturally, also other materials may be contemplated in order to manufacture a suitable stiff carrying base.
In a further embodiment of the invention illustrated with reference to figures 2 and 3 the stiff carrying base is constructed by assembling steel profiles. The steel profiles 12 are assembled into a lifting cradle generally having a U- shape meaning that there is a central flat portion 52 and in either end of this flat portion 52 are provided two upstanding sections 54, 56. A number of rollers 58 are provided such that a lifting strap (not illustrated) will be guided around the underside of the stiff carrying base 12 not coming into contact with the blade as such.
The stiff carrying base 12 is furthermore provided with a plate 60 on an upper side of the steel profiles 52. On top of the plate are arranged resilient pads in the same fashion as discussed above with reference to figure 1. In this manner the resilient pads 22, 24, 26 will be able to accommodate a wind turbine blade as discussed above with reference to figure 1. Naturally, the characteristics of the resilient pads may be determined as already discussed.
The resilient pads may comprise locking pins 74 to releasably interlock with holes 72 in the plate 60, such that the pads are releasably arranged on the plate for achieving an adjustable and modular cradle.
Exemplary embodiment comprising engagement means comprised in the plate 60 and in the resilient pads 22, 24, 26 are illustrated in figures 4 and 5.
In the illustrated embodiment of the cradle in figure 4, the engagement means of the resilient pads are provided by locking pins 74 configured to interlock with holes 72 in the plate 60. An alternative embodiment could be achieved by omitting the plate 60 and provide the holes in the carrying base.
In the illustrated embodiment of the cradle in figure 5, the engagement means provided in the plate 60 are provided by toothed rack 82 interlocked with the engagement means of the resilient pad provided by locking teeth 84. An alternative embodiment could be achieved by omitting the plate 60 and provide the toothed rack in the carrying base.
The stiff carrying base 12 is furthermore provided with wheels 62 such that the entire lifting cradle 10 easily may be positioned correctly relative to the blade or moved e.g. to storage. In figure 3 is illustrated a similar lifting cradle 10 where a blade has been positioned on top of the resilient pads. As may be seen, the resilient pad 26 has been compressed due to the load of the blade 30 and as such the lifting cradle 10 is in a supporting mode where the weight of the blade 30 has been optimally distributed on the carrying surfaces of the resilient pads.
As may be seen the stiff carrying base 12 is provided with brackets 66 in addition to the wheels 62 and stabilizing pegs 64 such that the carrying base will be stable when it is positioned on a flat surface. These brackets are dimensioned such that a forklift may engage and move the lifting cradle.
When a blade 30 is to be lifted by a lifting cradle 10 according to the invention the resilient pads, see for example figure 2, are dimensioned such that when the resilient pads 22, 26 are deformed due to the load from the blade as described above with reference to figure 3 these pads are selected such that they are suitable for the particular blade in question.
The lifting cradle is positioned underneath the blade such that the blade may be lowered onto the lifting cradle and arrive at a position for example as illustrated in figures 1 or 3. At this time the lifting cradle with the blade is ready to be lifted, and for this purpose a lifting strap or sling may be positioned around the underside of the lifting cradle in contact with the rollers as described above with reference to figures 2 and 3 or guided into the shallow grooves 16 illustrated and described with reference to figure 1. Once a crane or the like lifts the lifting cradle with the blade in the cradle it is possible due to the provision of the rollers or the low friction shallow grooves to alter the exact position of the lifting cradle whereby the blade is maintained in its optimum position.

Claims

1. Lifting cradle, suitable to lift and support a wind turbine blade, where said cradle comprises a stiff carrying base, said carrying base having an underside and an upper side, where guide means are provided in or along the underside, said guide means is suitable to slidingly hold a lifting strap or sling, and where on the upper side, two or more resilient pads are arranged where said pads are deformable when exposed to a load, and where on the upper side a further resilient pad are arranged between at least two of the resilient pads, where said further resilient pad is being less deformable than the two other pads, where all pads have a support surface adapted to receive and support a load.
2. Lifting cradle according to claim 1 wherein the carrying base is made from a polymer material optionally reinforced with fibers, glass or the like, and provided with at least one profile embedded in the underside, said profile being dimensioned to accommodate the lifting strap or sling, where the profile is made from steel, carbon or glass fiber reinforced resin.
3. Lifting cradle according to claim 2 wherein the side of the profile which is intended to be in contact with the lifting strap or sling has a low friction surface or is provided with a low friction treatment.
4. Lifting cradle according to claim 1 wherein the carrying base is made from steel profiles, said steel profiles being bent into a U-shape, where a wind turbine blade may be fitted inside the U and a number of guide rollers are arranged along the underside and in either end of the U for guiding the lifting strap or sling.
5. Lifting cradle according to claim 4 wherein a plate is provided on said steel profiles, where the two or more resilient pads are arranged on said plate and the further resilient pad being less deformable than the two other pads is arranged on said plate between the two or more resilient pads.
6. Lifting cradle according to claim 4 or 5 wherein wheels are provided, extending from the steel profiles or the plate in a direction opposite towards where the wind turbine blade is to be accommodated.
7. Lifting cradle according to any preceding claim wherein the at least one of the two or more resilient pads is made from polyurethane, and where a plurality of apertures are arranged through the pads, such that the resiliency of the pad is designed for a particular load or load distribution, and where the resiliency in one pad may vary across the pad’s support surface.
8. Lifting cradle according to any preceding claim wherein the resilient pad being less deformable than the two other pads is made from solid polyurethane.
9. Lifting cradle according to any of the preceding claim wherein the carrying base or the plate comprises first engagement means at the upper side and at least one of said resilient pads comprises second engagement means adapted to releasably interlock with the first engagement means so that said resilient pad(s) are releasably arranged on the upper side of the base or on the plate.
10. Method of using a lifting cradle according to any preceding claim, wherein the cradle is positioned on a flat surface, and a wind turbine blade is then lowered onto the cradle such that a main bulkhead inside the wind turbine blade or in the absence of a bulkhead the greatest cross-section measurement of the blade orthogonal to the longitudinal extend of the blade is positioned on the resilient pad being less deformable than the two other pads, and where a lifting strap or sling is positioned in the guide means provided in or along the underside of the cradle either before the blade is lowered onto the cradle or after the blade is positioned in the cradle; lift is then applied to the lifting strap or sling, such that the cradle and blade are elevated from the surface; and optionally the blade’s position is adjusted by letting the blade and cradle slide relative to the lifting strap or sling.
11. A kit for the lifting cradle according to any one or more of claims 1 to 9, comprising: - the stiff carrying base having an underside and an upper side, where guide means are provided in or along the underside, said guide means are suitable to slidingly hold a lifting strap or sling, and where on the upper side,
- two or more resilient pads adapted to be arranged on the upper side of the base, where said pads are deformable when exposed to a load, and
- at least the one further resilient pad adapted to be arranged on the upper side of the base, where said further resilient pad is less deformable than the two or more other resilient pads, wherein said base comprising first engagement means and at least one of said resilient pads comprises second engagement means adapted to interlock with first engagement means.
12. The kit according to claim 11 comprising a plate with the first engagement means, said plate is adapted to be arranged on the upper side of the carrying case.
PCT/DK2022/050300 2021-12-22 2022-12-21 Cradle WO2023117018A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DKPA202170657 2021-12-22
DKPA202170657 2021-12-22

Publications (1)

Publication Number Publication Date
WO2023117018A1 true WO2023117018A1 (en) 2023-06-29

Family

ID=85017673

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/DK2022/050300 WO2023117018A1 (en) 2021-12-22 2022-12-21 Cradle

Country Status (2)

Country Link
DK (2) DK202270531A1 (en)
WO (1) WO2023117018A1 (en)

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2010216317A (en) * 2009-03-14 2010-09-30 Kuribayashi Kiko Kk Inversive supporting device for wind power generation vanes
WO2012062352A1 (en) * 2010-11-08 2012-05-18 Alstom Wind, S.L.U. Lifting beam for use in hoisting a wind turbine blade
EP3134244A1 (en) * 2014-04-24 2017-03-01 LM WP Patent Holding A/S A wind turbine blade manufacturing system and method
WO2019129329A1 (en) * 2017-12-28 2019-07-04 Vestas Wind Systems A/S Support frame and method for determining movements of a wind turbine blade during transport to an installation site
WO2021077207A1 (en) * 2019-10-22 2021-04-29 LiftWerx Holdings Inc. Lifting system for a rotor blade of a wind turbine

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2010216317A (en) * 2009-03-14 2010-09-30 Kuribayashi Kiko Kk Inversive supporting device for wind power generation vanes
WO2012062352A1 (en) * 2010-11-08 2012-05-18 Alstom Wind, S.L.U. Lifting beam for use in hoisting a wind turbine blade
EP3134244A1 (en) * 2014-04-24 2017-03-01 LM WP Patent Holding A/S A wind turbine blade manufacturing system and method
WO2019129329A1 (en) * 2017-12-28 2019-07-04 Vestas Wind Systems A/S Support frame and method for determining movements of a wind turbine blade during transport to an installation site
WO2021077207A1 (en) * 2019-10-22 2021-04-29 LiftWerx Holdings Inc. Lifting system for a rotor blade of a wind turbine

Also Published As

Publication number Publication date
DK202270531A1 (en) 2023-06-27
DK202270637A1 (en) 2023-06-27

Similar Documents

Publication Publication Date Title
EP3211187B1 (en) Positioning system for aligning industrial machine coupling elements
EP0185891B1 (en) Lift device of the scissor-jack type
US5836463A (en) Powered lifting apparatus using multiple booms
CN106516181A (en) Large-bearing low-rigidity suspension system for simulating on-orbit weightless environment of spacecraft
WO2023117018A1 (en) Cradle
CN113734983A (en) Steel case roof beam hoist device for construction
CN105800420A (en) Rope lifting tool and rope lifting arrangement
EP2238072B1 (en) Tension holder for load lifting
CN110803597B (en) Belt with layered load bearing elements
RU181275U1 (en) TEST STAND FOR MOBILE DRILLING AND LOADING EQUIPMENT
CN115215199A (en) Integral hoisting method for large-diameter variable-circular-section steel bar section steel bars
CN113928979B (en) Floor turning-over method for transverse compartment block of container ship
MX2007009682A (en) Elevator support means for an elevator system, elevator system with such an elevator support means and method for assembling such an elevator system.
DK2771234T3 (en) Insertion or retraction of an elongate member to or from a body
CN112193986B (en) Gantry crane steel wire rope connecting piece and connecting method
EP2362021A1 (en) A turning arrangement for turning an elongated element, method and uses of the turning arrangement
CN115776968A (en) Extension yoke for a jack-up crane, jack-up wind turbine crane with an extension yoke and use of an extension yoke
FI61544C (en) ANORDINATION FOR STYLING AV GJUTFORMAR
KR20090076842A (en) System and method for launching ship by lifting of building berth
WO2023117016A1 (en) Storage cradle
DK202070816A1 (en) Method for lifting a wind turbine structure
NO784056L (en) CRANE WINCH MECHANISM.
CN113401799A (en) Hoisting method of giant thin deck block
EP1911715B1 (en) Elevator system having drive motor located at the bottom portion of the hoistway
US11981541B2 (en) Lifting device

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 22846894

Country of ref document: EP

Kind code of ref document: A1