DK201770509A1

DK201770509A1 - Crane for wind turbine installation

Info

Publication number: DK201770509A1
Application number: DKPA201770509A
Authority: DK
Inventors: Gal Zoran
Original assignee: Maersk Supply Service A/S
Priority date: 2017-06-28
Filing date: 2017-06-28
Publication date: 2019-02-08

Abstract

The invention relates to a method for moving a crane along a tower construction, the method comprising rotating a number of wheels, each with a rotational axis, where the wheels are located on the crane and brought into contact with the tower construction at least at three locations of the towercircumference, and where at least some of the wheels are driven individually to move the crane along the tower construction. Further the invention relates to a crane device for carrying out the method.

Description

Title

Crane for wind turbine installation

Field of the invention

The present invention relates to the area of wind turbine installation and more particularly to the area of cranes used in connection with wind turbine installation.

Background of the invention

Many crane constructions have been suggested and used over time in the process of installing wind turbines. The installation of wind turbines may be both onshore and offshore and for both areas of installation cranes are used. The offshore installation does present a number of obstacles compared with the onshore installation, which makes the offshore installation considerably more time and resource consuming and hence significantly more costly. The present invention therefore has a particular relevance in the area of the offshore installations; however this does not mean that the same crane cannot be used onshore.

Objective of the invention

The object of the present invention is to therefore provide for a method and a crane for wind turbine installation that allows for faster installation.

Description of the invention

According to one aspect of the present invention the objective of the invention is achieved through a method for moving a crane along a tower construction, the method comprising rotating a number of wheels, each with a rotational axis, where the wheels are located on the crane and brought into contact with the tower construction at least at three locations of the tower circumference, and where at least some of the wheels are driven individually

DK 2017 70509 A1 to move the crane along the tower construction. Preferably all wheels are driven individually.

Due to the deployment of the crane on the tower construction the sensitivity to weather conditions is less significant than the typical vessel crane. Due to the wheel drive the movement of the crane may be adapted to accomplish heavy weights and hence may be used for the entire wind turbine assembly process.

In an embodiment two or more circumferential arrangements of at least three wheels are provided and where at least some of the wheels, preferably all the wheels are driven individually to move the crane along the tower. In practically applicable embodiments a higher number of circumferential arrangements, each with a higher number of wheels with tires are provided. In total the number of wheels often amount to more than 100 and even beyond 200, when the lifting requirement is particularly high.

In a further embodiment at least some of the wheels are driven individually by a motor, e.g. a hydraulic motor or an electrical motor. A transmission may be provided, e.g. as gearwheels orspockets with a drive chain.

In an embodiment the wheels are moved in a direction perpendicular to their rotational axis’ during movement along a conical surface of a wind turbine tower. The movement is performed through one preferably two actuators mounted between the carrier body and the wheel suspension. The actuators are preferably hydraulic actuators connected to a hydraulic pressure source and the pressure is controlled by sensor means ensuirng a certain minimum pressure in the actuator hereby ensuring a certain minimum pressure of the wheel and tire against the wind turbine tower.

DK 2017 70509 A1

According to another aspect of the invention the objective of the present invention is achieved through a crane device for performing the method according to the invention, the crane comprising three or more wheels adapted to be brought into contact with a tower construction at mutually distanced locations of the tower circumference and where for at least some of the wheels, preferably all the wheels, a motor is provided to move the crane along the tower.

In an embodiment two or more circumferential arrangements of at least three wheels are provided.

In an embodiment a suspension arrangement is provided for each wheel allowing movement of the wheel in a direction perpendicular to the axis of the wheel.

In an embodiment a movement device, preferably a hydraulic cylinder is provided for each wheel suspension to perform the perpendicular movement.

In an embodiment the crane comprises a circumferential carrier body, where part of the circumferential carrier body is hinged with the remaining carrier body to allow opening of the circumferential body for mounting on the foundation or transition piece and for removal from the completed tower construction.

In an embodiment the supply of power or hydraulic pressure is provided from a source on a vessel moored at the foundation.

Preferably the crane comprises a circumferential carrier body, where part of the circumferential carrier body is hinged with the remaining carrier body to allow opening of the circumferential body for mounting on the foundation or transition piece and for removal from the completed tower construction.

DK 2017 70509 A1

In an embodiment the wheel suspension and the wheels as well as the drive mechanisms and hydraulic movement mechanisms are mounted in or on the circumferential carrier body.

In an embodiment, at least some of the wheels, a brake mechanism is provided for allowing both controlled and emergency braking of the crane device along the tower construction.

In a further aspect of the invention the objective is achieved through a vessel for installing a crane on a foundation or transition piece, the vessel comprising a platform adapted for positioning the crane in an operational position on the foundation or transition piece.

In a still further aspect of the invention the objective is achieved through a method for transferring a crane to a foundation or transition piece by use of a vessel with a platform, the method comprising approaching the foundation or transition piece with a vessel, contacting the vessel with the foundation or transition piece, vertically and/or horizontally adjusting the platform to align with the foundation or transition piece, and transferring the crane to the foundation or transition piece.

The method may further comprise adjusting the vessel movement during the transfer process to compensate for movements e.g. occurring due to waves and/or current.

In an additional aspect of the invention the objective is achieved through a crane adapted for interchangeability of tools, where the tool on one side is adapted for receiving a locking mechanism held by a crane arm or alternatively the crane arm is adapted for receiving a locking mechanism held by the tool. Preferably the locking mechanism is however held by the crane arm in order to keep the tool as simple as possible.

DK 2017 70509 A1

In a further aspect of the invention the objective is achieved through one or more tools adapted for interoperability with the crane arms, hereby achieving a more rational operation of the crane, i.e. the crane may be used for several part operations during assembly of a wind turbine generator, preferably all necessary operations.

Brief description of the drawings

The invention will in the following be described with reference to one embodiment illustrated in the drawings where:

FIG. 1 shows schematically a vessel approaching a foundation with a transition piece;

Figure 2 shows a crane carrier body with a closed hinged part;

FIG. 3 shows schematically a crane carrier body with an open hinged part allowing mounting on and dismantling from the foundation/tower;

FIG. 4 shows schematically in more detail the drive elements of the crane; FIG. 5 shows schematically the engagement with and mounting of a tower segment;

FIG. 6 shows schematically the engagement with and mounting of a nacelle.

Description of an embodiment

From FIG. 1 the initial steps of the crane installation process appear schematically. A vessel 100 approaches the foundation for an offshore wind turbine. The foundation has been equipped with a transition piece 101 which forms the uppermost part of the construction onto which the crane need to be installed. The vessel comprises a platform adapted to be elevated or lowered according to the height of the transition piece. The crane 102 is located on the platform 103 and ready to be transferred to the transition piece when the platform has been levelled with the transition piece. Optionally the platform may be horizontally displaced in order to facilitate the transfer. The vessel carrying the platform may have means for stabilizing the position of the

DK 2017 70509 A1 vessel during the transition of the crane. These means may comprise propulsion means for compensating movements in sideways and vertical directions.

The platform has been brought ina appropriate position for the transfer and the crane may be moved on the platform. For the purpose of the movement the platform may be provided with rollers or balls for reducing/eliminating the friction. Alternatively the crane may carry such rollers or balls or wheels that may allow movement in varying directions. During the transfer and until reaching the intended position around the transition piece the carrier body is open for receiving the transition piece and is closed after the intended position is reached.

From FIG. 2 the main elements of the crane appear in more detail. The crane comprises a carrier body 1 adapted to circumferentially enclose the transition piece and further on the tower. The carrier body comprises two hinged parts 3,4 allowing for opening the circumferential carrier body and hereby allows the initial accommodation of the transition piece and later on the release from the tower. As mentioned above the two hinged parts are closed after the intended position has been reached and locking means are engaged with the two parts. A number of driving mechanisms are provided for moving the crane along the wind turbine tower. These are described in more detail in connection with FIG. 4.

In figure 3 is shown the same crane as shown in figure 2, however the two hinged part 3,4 are shown in open position.

From FIG. 4 the driving mechanisms appear more clearly. The driving mechanisms are mounted on the inside of the carrier body, facing the tower outer surface. Each drive mechanism comprises a suspension arm (s) 10, 11 pivotally hinged at one end on the inside of the carrier body and at the

DK 2017 70509 A1 opposed end the suspension arm is carrying a wheel 12. In this particular embodiment the suspension arm is carried at the carrier body by means of two bearings 13, 14 and the wheel 12 is carried on both sides by a shaft extending through the wheel. A motor drive 16 is mounted on the suspension arm and a transmission, either a chain or gear wheel transmission, is mounted between the motor 15 and the wheel 12. The motor 15 may be an electric motor or may be a hydraulic motor. A brake may be provided as well, hereby allowing the braking of the crane movement along the wind turbine tower. It should be appreciated that the number of driving mechanisms, i.e. the number of wheels, often will amount to several hundreds, as only a certain force may be transferred through each wheel. The number of wheels will hence depend on the dimensioning of the crane construction and the requirements to the lifting capability.

From FIG. 5 the engagement of the crane with a tower segment 25 appears in connection with mounting of this. A tool is provided which is adapted for fastening in relation to the connection flange 20 of the uppermost part of the tower segment. One or more support 21, 22 elements are provided for supporting the side of the tower segment during movement, which support elements allow for operation under more rough conditions. The tool further comprises a drive mechanism adapted to turn the tower segment slightly at the final installation process in order to align the bolt holes in the neighbouring flanges of the transition piece/installed tower segment and the segment under installation.

From FIG. 6 the lifting of a nacelle 30 appears. The nacelle is at lifting points at the uppermost part of this connected to a lifting frame through wires 31 . The frame will have dimensions approximately corresponding to those of the nacelle, allowing the wires to extend perpendicular between the lifting frame and the lifting points. The lifting frame is connected to the carrier body of the crane through an arm construction capable of extending the centre of the

DK 2017 70509 A1 lifting frame and maintaining the nacelle free of the tower construction. The wires may be horizontally movable in the carrier frame, hereby allowing a certain horizontal movement of the nacelle during the placement operation.

A tool appears is adapted to engage with a rotor part of a wind turbine, with or without the blades mounted on the rotor. The tool is held between the crane arms.

Another tool is adapted for the separate mounting of a blade on a rotor in case the rotor is mounted separately prior to the mounting of the blade mounting procedure.

The crane arms are provided at both sides of the tool in operation. The tool may be replaced by other tools in dependence of the particular part that needs lifting or a particular tool that fits the parts of a particular wind turbine manufacturer. The engagement between the crane arms and the tool is ensured through displaceable locking means, preferably locking shafts or bolts, that may be operated through remotely controlled motors. The crane arms for carrying the tools for tower parts and rotor/blades may be integrated with the nacelle lifting equipment and the above mentioned entension of the centre of the lifting frame may be performed through hydraulic actuators between the crane arms and the nacelle lifting tool.

The stability of the crane is ensured through a number of stabilizing arrangements placed in a way that counteracts the torsion movements of the crane arms.

When a nacelle has been placed in its operational position the crane is aligned with the nacelle and the stabilizing arrangements are disconnected in order to allow a pivotal movement of the arms over the nacelle. Hereby the crane arms are telescopically extendable to allow the movement. The

DK 2017 70509 A1 telescopic capability is solely for this purpose. Having performed the pivotal movement the crane carrier body may be transferred downwards without any obstacles and when transferred a certain distance the crane arms may be transferred back into their operational position by an opposite pivotal movement and the stabilising arrangements may be repositioned to allow for a further lift of a rotor and/or blades.

Claims

Claims

1. A method for moving a crane along a tower construction, the method comprising rotating a number of wheels, each with a rotational axis, where the wheels are located on the crane and brought into contact with the tower construction at least at three locations of the tower circumference, and where at least some of the wheels are driven individually to move the crane along the tower construction.
2. A method according to claim 1, where two or more circumferential arrangements of at least three wheels are provided and where at least some of the wheels, preferably all the wheels are driven individually to move the crane along the tower.
3. A method according to claim 1 or 2, where at least some of the wheels are driven individually by a motor, e.g. a hydraulic motor or an electrical motor.
4. A method according to any of the preceding claims, where the wheels are moved in a direction perpendicular to their rotational axis’ during movement along a conical surface.
5. A crane device for performing the method according to the invention, the crane comprising three or more wheels adapted to be brought into contact with a tower construction at mutually distanced locations of the tower circumference and where for at least some of the wheels, preferably all the wheels, a motor is provided to move the crane along the tower.
6. A crane device according to claim 5, where two or more circumferential arrangements of at least three wheels are provided.

DK 2017 70509 A1
7. A crane device according to claim 5 or 6, where a suspension arrangement is provided for each wheel allowing movement of the wheel in a direction perpendicular to the axis of the wheel.
8. A crane device according to claim 7, where a movement device, preferably a hydraulic cylinder is provided for each wheel suspension to perform the perpendicular movement.
9. A crane device according to claim 8, where a pressure sensor is provided for each hydraulic cylinder and connected to a control device for regulating the pressure of the hydraulic cylinder.
10. A crane device according to any of the preceding claims, where the supply of power or hydraulic pressure is provided from a source on a vessel moored at the foundation.
11. A crane device according to any of the preceding claims, where the crane comprises a circumferential carrier body, where part of the circumferential carrier body is hinged with the remaining carrier body to allow opening of the circumferential body for mounting on the foundation or transition piece and for removal from the completed tower construction.
12. A crane device according to claim 11, where the wheel suspension and the wheels as well as the drive mechanisms and hydraulic movement mechanisms are mounted in the circumferential carrier body.
13. A crane device according to any of the preceding claims, where for at least some of the wheels a brake mechanism is provided for allowing

DK 2017 70509 A1 both controlled and emergency braking of the crane device along the tower construction.
14. A vessel for installing a crane on a foundation or transition piece, the vessel comprising a platform adapted for positioning the crane according to any of the preceding claims in an operational position on the foundation or transition piece.
15. A method for transferring a crane according to any of the preceding claims to a foundation or transition piece by use of a vessel with a platform, the method comprising approaching the foundation or transition piece with a vessel, contacting the vessel with the foundation or transition piece, vertically and/or horizontally adjusting the platform to align with the foundation or transition piece, and transferring the crane to the foundation or transition piece.
16. A method according to claim 15, further comprising adjusting the vessel movement during the transfer process to compensate for movements e.g. occurring due to waves and/or current.