Abstract: Extendable lattice type crane boom (2) for a crane (1), the boom comprising a lattice type base boom section (2a) and at least one lattice type telescopic boom section (2b), wherein the at least one telescopic boom section is adjustable with respect to the base boom section between a retracted position, in which the telescopic boom section is substantially inside of the base boom section, and an extended position, in which the telescopic boom section is at least partly outside of the base boom section, wherein a distal end of the base boom section to which a first guiding system (21) is mounted, the guiding system being configured to guide a movement of the telescopic boom section along the base boom section; wherein a proximal end of the telescopic boom section comprises a second guiding system (30) configured to guide a movement of the telescopic boom section along the base boom section.

Abstract: A method is provided for determining an actual achieved pre-load value by monitoring a leg load characteristic during pre-loading. The method further comprises determining an actual crane or cantilever operations envelope taking into account the actual achieved preload instead. The method further comprises taking into account other data such as environmental loads or crane or cantilever movement.

Abstract: Drilling installation comprising a cantilever with a drilling floor for performing drilling operations; further comprising an independent operations handling system arranged for handling equipment underneath the drilling floor independent of the drilling operations on the drilling floor, wherein the independent operations handling system comprises a handling element for cooperation with the equipment to be handled, wherein the handling element is extendible underneath the cantilever.

Abstract: For controlling movement of a cantilever of an offshore platform, displacements required for displacing an item to a target position including longitudinal skidding displacement and transverse skidding displacement of the cantilever of the cantilever are determined from current position data and target position data. From position dependent support load data support loads during the longitudinal skidding displacement are determined. If and until a sum of support loads or a highest support load decreases during the longitudinal skidding displacement towards the target position, the longitudinal skidding displacement precedes the transverse skidding displacement. If a sum of support loads or a highest support load increases during the longitudinal skidding displacement towards the target position, the transverse skidding displacement towards the target position precedes the longitudinal skidding displacement.

Abstract: Telescopic lattice type crane boom for a crane, further comprising a locking system configured to lock at least one telescopic boom section with respect to a base boom section in at least an extended position, wherein said locking system includes a plurality of pins, each pin being configured to extend, in at least the extended position of the boom, at least partly through a corresponding pin receiving aperture provided in one of the base boom section and the at least one telescopic boom section.

Abstract: Method for stabilizing a jack-up platform unit, the unit including a hull, a plurality of legs which are extendible from and/or through the hull and which are arranged to support the platform unit during off-shore operations, and a jacking system arranged to move the legs between a transport position and an operational position, wherein the jacking system is also arranged to move the hull along the plurality of legs between a floating position and an operational position, the method comprising the steps of lowering the plurality of legs until the legs stand on or in the seabed, raising the hull substantially above the sea surface, temporarily applying a preloading on the plurality of legs, further raising the hull to an operational height above the sea surface.

Abstract: Drilling installation comprising a cantilever with a drilling floor for performing drilling operations; further comprising an independent operations handling system arranged for handling equipment underneath the drilling floor independent of the drilling operations on the drilling floor, wherein the independent operations handling system comprises a handling element for cooperation with the equipment to be handled, wherein the handling element is extendible underneath the cantilever.

Abstract: A method for monitoring movement of a cantilever structure of an offshore platform, such as a jack-up platform or a self-elevating vessel, comprising providing a boundary model containing boundary limiting information of positions of the cantilever structure, wherein the boundary limiting information comprises at least position information of boundary limiting elements, such as obstacles; providing, during movement of the cantilever, position information of the cantilever representing an actual position of the cantilever; determining, during movement of the cantilever, a difference between the cantilever position information and the boundary limiting information of the boundary model; providing an output signal when the determined difference exceeds a predefined threshold value.

Abstract: A measurement system that comprises at least one horizontal load measuring unit, that is preferably arranged on the leg guide is provided. The horizontal load measuring device measures or determines horizontal load on the position of the leg where the device is placed, which gives a more accurate indication of the leg bending moment than the rack phase differential measurement. Advantageously, multiple load measuring units can be provided along the leg guide.

Abstract: Drilling installation comprising a cantilever with a drilling floor for performing drilling operations; further comprising an independent operations handling system arranged for handling equipment underneath the drilling floor independent of the drilling operations on the drilling floor, wherein the independent operations handling system comprises a handling element for cooperation with the equipment to be handled, wherein the handling element is extendible underneath the cantilever.

Abstract: The invention relates to a vessel (1), especially a drillship or so-called drilling ship. The vessel comprises a hull (3) having a bottom surface (5) and a deck (7). Said vessel is provided with a moon pool (2), which extends from said bottom surface of the hull in an upward direction through the hull. Further, said vessel is provided with a cavity (10) located at a front side of the moon pool. Said cavity is at least partly open at a bottom side thereof in order to allow water to flow into said cavity. Moreover, said cavity is at least partly open at a rear side of said cavity in order to allow water to flow directly from said cavity into the moon pool, as a result of which moon pool sloshing can be diminished and the mean flow resistance of the vessel when sailing can be reduced.

Abstract: Retractable thruster system for moving a thruster (1) on a vessel between an extended position, in which the thruster (1) is extended below a hull's bottom, and at least one retracted position, in which the thruster is located above the hull's bottom, the system comprising a canister (2) to which a thruster is mountable, wherein the canister is configured to be movable in a trunk (3) in a vessel's hull structure between said extended position and said at least one retracted position, and in which a rack-and-pinion lifting system is arranged to move the canister (3) in said trunk (3) between said extended position and said at least one retracted position, the lifting system including at least one rack (6) being fixedly connected to the vessel, and a pinion drive (7) including at least one pinion (8) arranged to cooperate with said at least one rack (6), said pinion drive being connected to the canister (2).

Abstract: The invention relates to a vessel, especially a drillship or so-called drilling ship. The vessel comprises a hull having a bottom surface and a deck. A moon pool extends from the bottom surface of the hull in an upward direction through the hull. Further, the vessel is provided with a cavity located at a rear side of the moon pool, with the cavity being at least partly open at a front side to allow water to flow from the moon pool directly into the cavity. Further, the cavity is at least partly open at a bottom side to allow water to flow out of the cavity. The cavity is defined at least partly by a trailing wall sloping downwards in a rearward direction and at least partly by a ceiling connecting a rear wall of the moon pool with the downwardly sloping trailing wall.