Described is a device for lifting an elongated object from a deck of a vessel subject to movements in a heave direction. The device comprises rigid supports provided on the deck of the vessel for supporting the object at a first height relative to the deck, and retractable supports provided on the deck of the vessel for supporting the object at a second height relative to the deck, which second height is larger than the first height. A lifting crane is configured to take up the object from the retractable supports at the second height. An actuator system is configured to lower the retractable supports in the heave direction to a third height relative to the deck at the instant in time the object is lifted from the retractable supports, the third height being smaller than the second height. A method using the device is also described.

Described is a device for lifting an elongated object from a deck of a vessel subject to movements in a heave direction. The device comprises rigid supports provided on the deck of the vessel for supporting the object at a first height relative to the deck, and retractable supports provided on the deck of the vessel for supporting the object at a second height relative to the deck, which second height is larger than the first height. A lifting crane is configured to take up the object from the retractable supports at the second height. An actuator system is configured to lower the retractable supports in the heave direction to a third height relative to the deck at the instant in time the object is lifted from the retractable supports, the third height being smaller than the second height. A method using the device is also described.

An offshore wind turbine installation vessel includes a crane provided with a computerized crane control system. The computerized crane control system is linked to the slew drive, the luffing drive, and the hoisting winch of the crane, and is programmed to perform a foundation pile installation routine providing a coordinated pattern of slew motion of the superstructure and of luffing motion of the boom structure, as well as operation of the hoisting winch so that the load connector of the crane moves from a foundation pile pick up position thereof, where the load connector is connected to the top end of a horizontally oriented foundation pile stored on a storage deck, to a foundation pile overboarding position thereof, wherein the foundation pile is in vertical suspended from the load connector, outside of the hull.

A lifting apparatus comprises: a base part, a lifting rope, a sheave assembly, a first rotatably mounted sheave, around which the rope passes and from which the rope extends downwardly to a load, a second rotatably mounted sheave and a drive for moving the sheave assembly. The sheave assembly is mounted for pivotal movement relative to the base part about an axis of pivoting spaced from the axis of rotation of the first sheave and coincident with the axis of rotation of the second sheave. During movement of the load relative to the base part, the first sheave is moved by the drive to compensate for that relative movement, the movement of the first sheave being such that the vertical component of the movement of the first sheave relative to the load is less than the vertical component of the movement of the base part relative to the load.

A lifting apparatus comprises: a base part, a lifting rope, a sheave assembly, a first rotatably mounted sheave, around which the rope passes and from which the rope extends downwardly to a load, a second rotatably mounted sheave and a drive for moving the sheave assembly. The sheave assembly is mounted for pivotal movement relative to the base part about an axis of pivoting spaced from the axis of rotation of the first sheave and coincident with the axis of rotation of the second sheave. During movement of the load relative to the base part, the first sheave is moved by the drive to compensate for that relative movement, the movement of the first sheave being such that the vertical component of the movement of the first sheave relative to the load is less than the vertical component of the movement of the base part relative to the load.

A damping device includes a cable to be connected to a mass; a winch for hauling in and paying out the cable; a measurement system for measuring a cable motion relative to the winch and for measuring a cable tension in the cable; a control system for damping cable motion by driving the winch in dependency of the measured cable motion and the measured cable tension; a sheave to guide the cable from the winch to the mass, wherein the measurement system is configured to measure the cable tension by measuring a magnitude of a load on the sheave caused by the cable tension.

A damping device includes a cable to be connected to a mass; a winch for hauling in and paying out the cable; a measurement system for measuring a cable motion relative to the winch and for measuring a cable tension in the cable; a control system for damping cable motion by driving the winch in dependency of the measured cable motion and the measured cable tension; a sheave to guide the cable from the winch to the mass, wherein the measurement system is configured to measure the cable tension by measuring a magnitude of a load on the sheave caused by the cable tension.

The present embodiments relate to launch and recovery systems for a remotely operated vehicle. The embodiments eliminate or minimize the need for load lines, and provide virtually unlimited excursion distances for remotely operated vehicles, limited only by the amount of tether available at the launch point. Further, the embodiments allow for extended deployments of ROVs by allowing recharging of a tether climbing component while submerged. The system can include a launch and recovery assembly, a tether climbing component, and a remotely operated vehicle attached to a remotely operated vehicle tether. The launch and recovery assembly deploys the remotely operated vehicle and the tether climbing component overboard, and the remotely operated vehicle is configured for tethered operation while maintaining the tether climbing component at a desired depth.

The present embodiments relate to launch and recovery systems for a remotely operated vehicle. The embodiments eliminate or minimize the need for load lines, and provide virtually unlimited excursion distances for remotely operated vehicles, limited only by the amount of tether available at the launch point. Further, the embodiments allow for extended deployments of ROVs by allowing recharging of a tether climbing component while submerged. The system can include a launch and recovery assembly, a tether climbing component, and a remotely operated vehicle attached to a remotely operated vehicle tether. The launch and recovery assembly deploys the remotely operated vehicle and the tether climbing component overboard, and the remotely operated vehicle is configured for tethered operation while maintaining the tether climbing component at a desired depth.

An offshore system includes a vessel having a deck; a cantilever which is mounted on the deck and which is moveable in a longitudinal direction of the cantilever relative to the deck between a retracted position and an extended position, and which is rotatable relative to the deck about a substantially vertical swivel axis; and actuators to move the cantilever in longitudinal direction and to rotate the cantilever about the swivel axis. The swivel axis is provided by a single sliding and swivel assembly arranged at one end of the cantilever, including a fixed part mounted to the deck and a sliding part mounted to the cantilever. The sliding part is arranged to slide in longitudinal direction of the cantilever relative to the fixed part when the cantilever moves in the longitudinal direction. The fixed part and/or the combination of fixed part and sliding part are configured to form the swivel axis allowing the cantilever to rotate relative to the deck. A sliding assembly is arranged at the other end of the cantilever supporting the cantilever and allowing the cantilever to slide in longitudinal direction of the cantilever relative to the deck during movement of the cantilever in longitudinal direction, and to slide in a transverse direction perpendicular to the longitudinal direction relative to the deck during rotation of the cantilever relative to the deck.