Provided is a lifting arrangement configured to facilitate alignment of a load with a wind turbine assembly. The lifting arrangement includes a crane arrangement for hoisting the load to the wind turbine assembly, a tagline arrangement for stabilizing the load during a lifting manoeuvre, a sensor arrangement configured to detect a motion of the wind turbine assembly relative to the load during the lifting manoeuvre, an actuator arrangement for adjusting the position of the load relative to the wind turbine assembly, and a control arrangement for controlling actuators of the actuator arrangement to reduce the detected relative motion. Also provided is a method of aligning a load with a wind turbine assembly.

A crane is provided. The crane includes an acceleration sensor that detects the acceleration of a load, wherein a target velocity signal is converted into target location coordinates of the load, current location coordinates of a boom are calculated from a slewing angle, a luffing angle, and an expansion/contraction length, the spring constant of a wire rope is calculated from the previously calculated location of the load from a unit time earlier, the current location coordinates of the boom, and the current accelerations of the load as detected by the acceleration sensor, target location coordinates of the boom are calculated from the accelerations, the spring constant, and the target location coordinates of the load, and an actuator operation signal is generated.

Provided is a system for assembling or disassembling components of a wind turbine including: a motion compensation mechanism, wherein the motion compensation mechanism includes: a first connection interface for connection with a first component of the wind turbine moved by a crane, a second connection interface for connection with a second component of the wind turbine, a tension element connecting the first connection interface and the second connection interface, and a tension device for keeping the tension element under constant tension as the first component and the second component move relative to each other, wherein the motion compensation mechanism allows a movement of the first component relative to the second component as the first component and the second component are moved relative to each other on a given trajectory.

A winch (100, 200) includes a rope (105), an overwinding sensor (106) coupled to the rope (105) where the overwinding sensor (106) is moveable between a first position and a second position upon winding and/or unwinding of the rope (105). The overwinding sensor (106) includes a first electrically conducting member, a contact member (104) having a second electrically conducting member which is contactable by the first electrically conducting member when the overwinding sensor (106) is in the second position. The second electrically conducting member is not contactable by the first electrically conducting member when the overwinding sensor (106) is in the first position. The winch (100, 200) is configured to stop and/or prevent and/or hamper winding of the rope (105) upon establishment of an electrical contact between the first electrically conducting member and the second electrically conducting member when the overwinding sensor (106) is in the second position.

A control method controls a movable member of an excavator including a movable member holding a load, an actuator with electric motor and static brake, a control unit and a motion sensor unit. The static brake and electric motor generate respectively an upper threshold brake force and an upper threshold motor force. An immobilization operation provides that the static brake generates the upper threshold brake force and the electric motor is stopped. A slippage detection operation provides that the control unit detects whether an electric actuator is moving despite the static brake. If the electric actuator is moving, a motor energizing operation provides that the electric motor generates a motor force equal or superior to upper threshold brake force in a direction opposite to the slippage direction. After energizing the motor, a brake release operation provides that the control unit releases the static brake.

A method of upgrading a knuckle-boom crane to a heave-compensating crane includes: removing a knuckle-boom from a main boom; mounting a main boom extension to the main boom for increasing the length of the main boom; and mounting a heave-compensating boom at a far end of the main boom extension such that the heave-compensating boom extends in a downward vertical direction (Z) in operational use of the heave-compensating crane. The heave-compensating boom is configured to be pivotable with respect to the main boom extension in both horizontal directions (X, Y). A heave-compensation system is provided to the knuckle-boom crane, wherein the heave-compensation system compensates for horizontal variations by controlling the orientation of the heave-compensating boom relative to the main boom extension, and compensates for vertical variations by means of a further vertical heave-compensation system, such as a winch-based heave-compensation system.

A method of building an offshore windmill includes, using a 3D-heave-compensated crane, placing on a windmill pedestal a lifting jack having a receiving region, and fixing the lifting jack to the windmill pedestal such that the lifting jack can be later removed, and such that a windmill column can be placed within the receiving region directly on the windmill pedestal. The windmill generator is installed using the 3D-heave-compensated crane. The windmill column is partially erected on the windmill pedestal using the 3D-heave-compensated crane and the lifting jack. Before the windmill is fully erected, windmill blades are placed on the windmill generator using the 3D-heave-compensated crane, and the erection of the windmill column on the windmill pedestal is completed using at least the lifting jack. Using the 3D-heave-compensated crane, the lifting jack is removed from the windmill pedestal.

Transportable inline heave compensator provided with connection devices for suspending the compensator from a load bearing device and a connection device for a carrying a payload, where the compensator comprises a passive heave compensator part and possibly an active heave compensator part, and being provided with a sensor arrangement, where the compensator further comprises at least one actuator, that is horizontally oriented in operation and comprises an actuator piston rod with a horizontally stroke indirectly connected to a rope means, where the rope means at an end, via a connection device, such as a padeye, is connected to at least one of; a vessel at the sea surface or a payload, incorporating a device with a curved surface where rope means is suspended to for converting the vertical movements of vessel or payload to horizontal movements of the actuator piston rod compensating the load.

A wire rope device having adjustable length between a first end and a second end thereof. The wire rope device comprises a first wire rope extending from the first end and a second wire rope extending from the second end. A length adjusting structure is disposed between the first end and the second end. The length adjusting structure has the first wire rope and the second wire rope connected thereto. A support structure is disposed between the first end and the second end. The support structure has the length adjusting structure rotatable movable mounted thereto. A first guiding structure and a second guiding structure are disposed in the support structure for guiding the first wire rope and the second wire rope, respectively, such that when in operation a portion of the first wire rope extending from the first guiding element and a portion of the second wire rope extending from the second guiding element are disposed substantially along a same straight line. A drive mechanism is mounted to the support structure and connected to the length adjusting structure for adjusting the length of the wire rope device by rotatably moving the length adjusting structure.

A method of building an offshore windmill includes, using a 3D-heave-compensated crane, placing on a windmill pedestal a lifting jack having a receiving region, and fixing the lifting jack to the windmill pedestal such that the lifting jack can be later removed, and such that a windmill column can be placed within the receiving region directly on the windmill pedestal. The windmill generator is installed using the 3D-heave-compensated crane. The windmill column is partially erected on the windmill pedestal using the 3D-heave-compensated crane and the lifting jack. Before the windmill is fully erected, windmill blades are placed on the windmill generator using the 3D-heave-compensated crane, and the erection of the windmill column on the windmill pedestal is completed using at least the lifting jack. Using the 3D-heave-compensated crane, the lifting jack is removed from the windmill pedestal.