An oil storage apparatus (111) comprising a buoyant hull (102) comprising a single column of circular or polygonal cross-section. The interior of said hull (102) comprises at least one oil-over-water tank (103), and said oil storage apparatus (111) further comprises means for maintaining said tank in pressed full condition.

A porous-structure device includes a semi-submersible platform consisting of four columns, two pontoons, two horizontal supports and a deck. Fillets on middle portions of the columns have a square section, a radius of the fillets, close to the deck and the pontoons, of the columns is gradually decreased to 0, a porous device is disposed outside each column and is formed by combining and connecting four single components, and each single component is formed by combining and connecting a plurality of porous laminated plates and a plurality of connecting pieces. The parameters, such as the pore type, porosity, number of layers, interlayer spacing and installation height, of the porous laminated plates are set according to the wave characteristics in different sea areas.

A floating offshore wind power generation facility includes a floating body, a mooring cable, a tower, and a windmill installed at the top of the tower, the windmill including a nacelle and a plurality of blades. The rotation axis of the windmill has a predetermined upward angle to avoid contact between the blades and the tower, and the windmill is of a downwind type in which the blades are attached to the leeward side of the nacelle and installed with the back surfaces of the blades facing windward, and the mooring point of the mooring cable to the floating body is set at a position below the surface of the sea and higher than the center of gravity of the floating body.

The present invention provides a floating offshore wind turbine capable of suppressing yawing of a nacelle caused by a gyro effect which is a cause of adverse influence of power generating efficiency of a wind turbine and endurance of devices thereof. The floating offshore wind turbine 10 includes a rotor 11 which is rotated by wind, a nacelle 13 in which a rotation shaft 12 of the rotor 11 is accommodated, and a tower 15 including a turning seated bearing 14 which supports the nacelle 13 such that the nacelle 13 can turn with respect to a sea surface P to exert a weathercock effect. The tower is provided with yawing suppressing means 16 which suppresses yawing T of the nacelle 13. According to this, it is possible to suppress the yawing T of the nacelle 13 generated by a gyro effect caused by yawing Ω generated in the floating body 31 by waves of the sea surface P.

The present invention relates a wind turbine comprising a wind turbine tower with a nacelle provided on the top to which a rotor hub with one or more wind turbine blades is rotatably mounted so that they form a rotor plane. A floating foundation having a upper section is mounted to the bottom of the wind turbine tower, wherein the foundation has a buoyant body configured to be installed at an offshore position having a water depth of about 40 m or more. The wind turbine blade comprises an inner blade section coupled to an outer blade section by a pitch junction in which a pitch mechanism is coupled to a pitch control system configured to regulate the pitch of the outer blade section relative to the inner blade section at wind speeds above a first wind speed. This allows the pitching to be used to counteract the tilting of the wind turbine caused by the different thrusts acting on the structure. This allows for a more linear control of the bending moment induced in the structure, since the blade sections provides a more constant thrust acting on the rotor hub which in turn allows the large negative damping loads and stresses introduced in the wind turbine to be eliminated.

Disclosed embodiments relate to systems and methods for mating a wind turbine off-shore to a spar buoy without the use of a crane barge. The system may include a spar buoy, wherein the spar buoy is secured to a foundation, and a wind turbine to be installed on the spar buoy. The system may also include a first truss affixed to the top of the spar buoy and a second truss affixed to the bottom of the wind turbine. The first truss may comprise either stabbings or receptacles configured for mating to the second truss and the second truss may comprise either receptacles or stabbings configured for mating to the first truss.

A marine platform (and method of installation) provides a plurality of buoys of special configuration, a platform having a peripheral portion that includes a plurality of attachment positions, one attachment position for each buoy, and an articulating connection that connects each buoy to the platform at a respective attachment position, the connection allowing for sea state induced buoy motions while minimizing effect on the platform. A method of installation places the platform (including oil and gas drilling and/or production facility) next to the buoys. Ballasting moves the platform and buoys relative to one another until connections are perfected between each buoy and the platform.

A floating structure in the form of a spar which from a base (12) includes a first ballast weight (16), an entrapped fluid compartment (18), an equipment compartment (20), a second ballast weight (22) and a topside (24) wherein, in use, the structure floats with the water line between the topside and the second ballast weight. The arrangement utilises vertical spacing between physical masses and entrapped fluid to increase the natural period in pitch and roll motions to provide high stability. Embodiments of entrapped fluid compartments are described. The floating structure finds application in hydrocarbon recovery in shallow water and offshore renewables.

A semi-submersible drilling vessel has a deckbox structure and a shaker room. A downward sloping mud return line is provided that passes mud from the diverter to the shaker room. In the shaker room there are one or more shale shaker devices, one or more upstream mud tanks arranged to receive gas cut mud from the one or more shale shaker devices, and a vacuum degasser having an inlet pipe extending into an upstream mud tank, a vacuum tank, a vacuum pump, and an outlet, and a degassed mud tank receiving degassed mud from the outlet of the vacuum degasser. The degassed mud tank has an effective height between the bottom thereof to the operational mud level in said degassed mud tank that is greater than the corresponding effective height of said one or more upstream mud tanks. The degassed mud tank is mounted so that—in operation—the operational mud level in said degassed mud tank is at least 1.5 meter, preferably at least 2 meters, higher than in said one or more upstream tanks with the vacuum degassers self-suction effect causing the mud to be pumped from the upstream tank, via the vacuum degasser, into the degassed mud tank.

A sea water intake riser system for a floating production unit, including a caisson having a through-opening in a bottom side and being connectable to an upper end of a riser pipe; a lift pump inside the caisson and having an inlet at a vertical distance with a predetermined minimum submergence for pumping cold water from the caisson up to the floating production unit for use as cooling medium, wherein the sea water intake riser system includes at least two caissons, having a height substantially equal to a vertical height of a hull of the floating production unit and including an open top side; each caisson extending from a predetermined minimum distance from the bottom side of the hull up to at least the water-line during use and wherein a sump tank is located between the bottom side of the hull and the at least two caissons.