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.

An offshore wind turbine support structure monitoring system and operating method are disclosed, comprising an offshore wind turbine, at least one state detection module, a data acquisition module, a data storage module, a network transmission module and at least one client. Thus, the maintenance of offshore wind turbines can be monitored directly and instantly to estimate the maintenance period, adjust the optimal operation and maintenance strategy, and save the cost.

The present invention generally relates to a continuous monitoring system and method for monitoring the loads in a support leg of an offshore drilling rig through a remote unit mounted to the climbing pinion shaft of a jacking drive system when the brake is engaged.

A crane system is for a cantilever belonging to a jack-up rig. The crane system has a crane with a suspension member, the suspension member being arranged over the crane. A skid beam is attached to a lower portion of the cantilever, the skid beam being displaceably connected to a plurality of slides arranged on the jack-up rig, the crane hanging on the skid beam. A method is for using the crane system.

A system and a method for an offshore platform that is self-installing, not requiring use of a heavy lift vessel for installation at a site. The system has a built-in, retractable, suspended, conductor guide support frame assembly coupled to the hull of the platform and serves as lateral guide/support for the well conductors/casings during operational conditions. The conductor guide support frame assembly is generally raised during wet tow/transit. At the site, the conductor guide support frame assembly is lowered and secured into the sea to its designated elevation. The conductor guide support frame assembly generally remains suspended from the hull and does not need to extend all the way to the seabed foundation. After operations are completed, the conductor guide support frame assembly is generally raised up relative to the hull, and the whole platform with the conductor guide support frame assembly relocated for reuse at a new site.

The present application discloses a dredging system for a pre-paved gravel foundation bed surface in open sea deep water, including a dredging mechanism, which includes a dredging suction head, a power component and a dredging pipeline, wherein the dredging suction head is connected with the dredging pipeline; the dredging pipeline is communicated with the power component; the dredging suction head includes at least one ridge surface suction port and at least one furrow suction port; the openings of all the furrow suction ports are lower than those of all the ridge surface suction ports; a lifting mechanism, which is connected with the dredging suction head and is used for lifting the dredging suction head to the gravel foundation bed surface; a moving mechanism, which is connected with the lifting mechanism and is used for driving the dredging suction head to move within a dredging range of the gravel foundation bed surface. By the adoption of the dredging system for the pre-paved gravel foundation bed surface in the open sea deep water of the present application, the dredging suction head includes the ridge surface suction ports and the furrow suction ports, and may suck mud on the top surfaces of gravel ridges and the mud in furrows between two gravel ridges at the same time, thereby guaranteeing the dredging quality of the gravel foundation bed surface and improving the working efficiency. The dredging system is simple in structure, convenient to use and good in dredging effect.

The invention relates to the naval field and in particular to a method for launching a structure (1) intended to float in water (15). This method comprises loading the structure (1) onto a pontoon (10) floating in the water, the bearing placement below the water (15) of at least one prop (2) connected to the structure (1) while the structure (1) rests on the pontoon (10) floating in the water (15), lowering the pontoon (10), with disengagement of the pontoon (10) vertically from the structure (1) and its subsequent removal while the structure (1) is supported by the at least one prop (2) bearing below the water (15), and lowering the structure (1), which is still supported by the at least one prop (2), until the structure (1) floats in the water (15).

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.

The offshore jack-up has a hull and a plurality of moveable legs engageable with the seafloor. The offshore jack-up is arranged to move the legs with respect to the hull to position the hull out of the water. The method comprises moving at least a portion of a vessel underneath the hull of the offshore jack-up or within a cut-out of the hull when the hull is positioned out of the water and the legs engage the seafloor. A stabilizing mechanism mounted on the jack-up is engaged against the vessel. The stabilizing mechanism is pushed down on the vessel to increase the buoyant force acting on the vessel.

Method for moving a cantilever with respect to a deck of an offshore structure in longitudinal and rotational direction, around a predetermined virtual vertical axis, without providing a fixed vertical rotation shaft, comprising providing an offshore structure with a cantilever movable with respect to a deck of the offshore structure, providing cantilever rails on the bottom side of the cantilever and providing a supporting member or a skid shoe to support the cantilever on the deck, wherein the supporting member or the skid shoe has a top part configured for allowing the cantilever rail to have an angle deviating from the centerline of the skid shoe during rotation of the cantilever.