Provided is a method for installing or uninstalling a component of a wind turbine, which component is moved with a lifting device at which the component is fixed with cables, whereby two ropes are fixed to the component, with each rope running to a winch attached at a previously installed component of the wind turbine, with the ropes crossing each other and being moved around the winches for tensioning the rope while the component is lowered to its installation position or is lifted from its installation position.

A method for handling of an offshore wind turbine component includes using a vessel having a hull on which a motion compensating crane is mounted. The crane includes a main boom; a main boom luffing assembly; a mobile hoist cable suspension member; and a hoist winch and a hoist cable driven by the hoist winch. An object suspension device is suspended from the hoist cable. The mobile hoist cable suspension member is supported by a motion compensating support device that is fitted to the tip end of the main boom, the motion compensating support device including one or more motor powered motion displacement actuator assemblies and a motion compensating support device controller. The method includes connecting the offshore wind turbine component to the object suspension device; and operating the motion compensating support device to provide motion compensation in at least one direction of the object suspension device and the connected offshore wind turbine component. The crane is provided with one or more nacelle position detectors that are configured and operated to sense at least one of actual position and actual motion of the nacelle or of one or more components in or on the nacelle, and the one or more nacelle position detectors are linked to the motion compensating support device controller.

A portable gantry crane formed of composite members includes a composite material I-beam. Two or more support members are formed of a composite material and each support member supports the I-beam when the portable gantry crane is in an upright position. Two or more end housings are included, each end housing enclosing a top end of one of the two or more support members and coupled thereto using adhesive. A plurality of latch structures are coupled with the I-beam, each latch structure including a latch, and each end housing having a latch receiver, each latch in combination with a latch receiver allowing one of the latch structures to be releasably fixedly coupled with an end housing. In implementations a plurality of latch structures are coupled with the I-beam, each latch structure having a latch structure enclosure and each latch structure enclosure at least partially enclosing one of the end housings.

A hoisting crane for use on an offshore vessel, such a vessel and a method for hoisting an offshore wind turbine component wherein use is made of such a crane and/or vessel. The hoisting crane includes a base structure, a superstructure, a boom having a longitudinal axis and a length of 80-200 meters. The boom includes a proximal portion connected to the boom connection member, formed integral via a joint structure with a single distal leg, wherein the length of the distal leg between the joint and the boom head structure exceeds 30 meters.

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.

The present invention relates to a method for installing a wind turbine or other tall structure at a target location at sea, the method comprising: providing an installation vessel comprising at least one crane, wherein the crane comprises a lower boom part, a right boom part, and a left boom part, wherein the right boom part and the left boom part are connected to an upper portion of the lower boom part and extend from said upper portion, wherein a space is present between the right and left boom part, lifting a tall structure part, in particular the nacelle assembly, with the crane, wherein in top view the tall structure part is supported at least partially between the right and left boom part by one or more hoist lines extending from the right and left boom part to the tall structure part.

This invention relates to a large crane with an at least two-part main boom, wherein a lower and an upper part of the main boom are pivotally coupled to each other an articulation point. The invention furthermore is directed to a method for erecting or depositing a corresponding large crane.

A climbing device for carrying out a movement relative to a tower, to a part-ring segment for a tower, to a tower, to a wind power installation, and to a method for producing a tower. A climbing device for carrying out a movement relative to a tower, comprising a main body having a longitudinal extent from a first end to a second end, wherein the second end in an operating state faces a foundation of a tower; at least one first climbing element having an extent between a first inner end and a first holding end; at least one second climbing element having an extent between a second inner end and a second holding end; wherein the first climbing element is disposed and configured for carrying out a first holding movement of the first holding end relative to the main body, by way of a first holding movement direction that is orthogonal to the longitudinal extent, and/or for carrying out a first climbing movement of the first holding end relative to the main body.

A motion compensating crane for use on an offshore vessel having a hull with a design waterline, wherein the crane includes a revolving superstructure, a main boom mounted to the revolving superstructure and pivotally connected at an inner end thereof about a substantially horizontal boom pivot axis to the revolving superstructure, the main boom having a tip end remote from the inner end, a main boom luffing assembly adapted to set an angle of the main boom relative to the superstructure within a main boom working angle range, a rigid jib frame pivotally connected to the tip end of the main boom about a substantially horizontal jib frame pivot axis, and a level setting assembly adapted to set the rigid jib frame in a levelled position whilst the main boom has an angle within the main boom working angle range. The rigid jib frame is provided with a set of parallel X-direction tracks which are substantially horizontal in the levelled position of the rigid jib frame. The crane further has a mobile carrier supported by the X-direction tracks and movable by a motor powered X-motion displacement actuator assembly. The mobile carrier is provided with one or multiple parallel Y-direction tracks and a mobile jib hoist cable suspension member is supported by the one or more Y-direction tracks and movable relative thereto.

A pressing-pulling device includes: a pressing-pulling bracket, wherein slotting oil cylinders are symmetrically and vertically mounted on the pressing-pulling bracket, and a piston rod of each of the slotting oil cylinders faces downwardly; a bottom end of the piston rod is connected to a connecting plate, and a through-hole is provided in a middle of the connecting plate; a continuous lifting mechanism is installed in a middle of the pressing-pulling bracket, and a slotting rod is vertically inserted into the continuous lifting mechanism; a lifting ring is installed at a top end of the slotting rod; a bottom end of the slotting rod extends downwardly through the through-hole to connect to a slotting cutter; a locking device is fixed on the connecting plate near the through-hole for fixing the slotting rod.