Abstract: An offshore structure includes an adjustably buoyant hull including a plurality of vertical columns and a plurality of horizontal pontoons. Each pontoon extends between a pair of the columns. The adjustably buoyant hull is configured to receive a topside. Each column has a central axis, an upper end, and a lower end. Each pontoon has a longitudinal axis, a first end coupled to one of the columns, and a second end coupled to another one of the columns. The offshore structure also includes a foundation assembly attached to a lower end of the hull. The foundation assembly includes a column skirt extending downward from the lower end of each column and a pontoon skirt extending downward from a bottom surface of each pontoon.

Abstract: Offshore production systems and methods relating thereto are disclosed. In an embodiment, the offshore production system includes a surface vessel. In addition, the offshore production system includes a closed-loop cooling fluid circulation system extending subsea from the vessel and configured to cool a cooling fluid. The closed-loop cooling fluid circulation system includes a first tendon having an upper end coupled to the surface vessel and a lower end coupled to the seabed. The first tendon is in tension between the upper end and the lower end. The first tendon is configured to flow the cooling fluid from the lower end of the first tendon to the upper end of the first tendon.

Abstract: An offshore production system includes a surface vessel, a tubular tendon extending between the surface vessel and a lower connection system disposed at a seabed, the riser coupled to the surface vessel with an upper connection system, and an electrical cable extending through a central passage of the tubular tendon, wherein the upper connection system comprises a connector that physically supports the electrical cable.

Abstract: A method for constructing a hull of an offshore structure includes (a) welding a plurality of plates together to form a plate assembly. The method also includes (b) passing the plate assembly through a rolling machine with the plate assembly in a vertical orientation. In addition, the method includes (c) bending the plate assembly into a cylinder during (b). The cylinder includes a pair of circumferentially adjacent free ends. Further, the method includes (d) welding the free ends of the cylinder together after (c) to form a cylindrical external wall.

Abstract: A floating offshore structure includes a buoyant hull including a first column, a second column, and a pontoon coupled to the first column and the second column. The pontoon extends horizontally from the first column to the second column. The pontoon includes a first tubular member, a second tubular member positioned laterally adjacent to the first tubular member, a first edge plate extending horizontally from the first tubular member, and a second edge plate extending horizontally from the second tubular member. The first tubular member and the second tubular member are disposed between the first edge plate and the second edge plate. Each tubular member has a central axis, a first end coupled to the lower end of the first column, and a second end coupled to the lower end of the second column. The longitudinal axis of the first tubular member and the longitudinal axis of the second tubular member are disposed in a common horizontal plane.

Abstract: An offshore wind turbine includes a ballast adjustable hull. In addition, the offshore wind turbine includes a telescopic tower movably coupled to the hull. The tower has a central axis and comprises a plurality of nested concentrically arranged elongate tubulars. Further, the offshore wind turbine includes a ballast adjustable elevator disposed about the telescopic tower and movably coupled to the hull. The elevator is configured to lift one or more of the plurality of tubulars of the tower axially upward relative to the hull. Still further, the offshore wind turbine includes a nacelle coupled to an upper end of one of the plurality of tubulars of the tower. Moreover, the offshore wind turbine includes a rotor assembly coupled to the nacelle.

Abstract: An offshore structure includes an adjustably buoyant hull including a plurality of vertical columns and a plurality of horizontal pontoons. Each pontoon extends between a pair of the columns. The adjustably buoyant hull is configured to receive a topside. Each column has a central axis, an upper end, and a lower end. Each pontoon has a longitudinal axis, a first end coupled to one of the columns, and a second end coupled to another one of the columns. The offshore structure also includes a foundation assembly attached to a lower end of the hull. The foundation assembly includes a column skirt extending downward from the lower end of each column and a pontoon skirt extending downward from a bottom surface of each pontoon.

Abstract: Offshore production systems and methods relating thereto are disclosed. In an embodiment, the offshore production system includes a surface vessel. In addition, the offshore production system includes a closed-loop cooling fluid circulation system extending subsea from the vessel and configured to cool a cooling fluid. The closed-loop cooling fluid circulation system includes a first tendon having an upper end coupled to the surface vessel and a lower end coupled to the seabed. The first tendon is in tension between the upper end and the lower end. The first tendon is configured to flow the cooling fluid from the lower end of the first tendon to the upper end of the first tendon.

Abstract: An offshore production system includes a surface vessel, a tubular tendon extending between the surface vessel and a lower connection system disposed at a seabed, the riser coupled to the surface vessel with an upper connection system, and an electrical cable extending through a central passage of the tubular tendon, wherein the upper connection system comprises a connector that physically supports the electrical cable.

Abstract: A method for constructing a hull of an offshore structure includes (a) welding a plurality of plates together to form a plate assembly. The method also includes (b) passing the plate assembly through a rolling machine with the plate assembly in a vertical orientation. In addition, the method includes (c) bending the plate assembly into a cylinder during (b). The cylinder includes a pair of circumferentially adjacent free ends. Further, the method includes (d) welding the free ends of the cylinder together after (c) to form a cylindrical external wall.

Abstract: A floating offshore structure includes a buoyant hull including a first column, a second column, and a pontoon coupled to the first column and the second column. The pontoon extends horizontally from the first column to the second column. The pontoon includes a first tubular member, a second tubular member positioned laterally adjacent to the first tubular member, a first edge plate extending horizontally from the first tubular member, and a second edge plate extending horizontally from the second tubular member. The first tubular member and the second tubular member are disposed between the first edge plate and the second edge plate. Each tubular member has a central axis, a first end coupled to the lower end of the first column, and a second end coupled to the lower end of the second column. The longitudinal axis of the first tubular member and the longitudinal axis of the second tubular member are disposed in a common horizontal plane.

Abstract: A floating offshore structure includes a buoyant hull including a first column, a second column, and a pontoon coupled to the first column and the second column. Each column is vertically oriented and the pontoon extends horizontally from the first column to the second column. Each column has a central axis, an upper end, and a lower end. The pontoon includes a first tubular member and a second tubular member positioned laterally adjacent to the first tubular member. Each tubular member has a central axis, a first end coupled to the lower end of the first column, and a second end coupled to the lower end of the second column. The longitudinal axis of the first tubular member and the longitudinal axis of the second tubular member are disposed in a common horizontal plane.

Abstract: A offshore system for storing oil includes a hull. The hull includes a buoyancy compartment and an oil storage compartment disposed below the buoyancy compartment. The oil storage compartment has an upper end, a lower end, and an inner cavity. In addition the system includes a water port in fluid communication with the inner cavity and configured to allow water to exit the inner cavity. Further, the system includes an oil heating and circulation system coupled to the hull. The oil heating and circulation system includes a suction line having an inlet disposed in the inner cavity proximal the upper end. The inlet is configured to draw oil from the inner cavity. The oil heating and circulation system also includes an oil heater coupled to the suction line and configured to heat oil passing through the suction line. Further, the system includes a return line coupled to the oil heater.

Abstract: A offshore system for storing oil includes a hull. The hull includes a buoyancy compartment and an oil storage compartment disposed below the buoyancy compartment. The oil storage compartment has an upper end, a lower end, and an inner cavity. In addition the system includes a water port in fluid communication with the inner cavity and configured to allow water to exit the inner cavity. Further, the system includes an oil heating and circulation system coupled to the hull. The oil heating and circulation system includes a suction line having an inlet disposed in the inner cavity proximal the upper end. The inlet is configured to draw oil from the inner cavity. The oil heating and circulation system also includes an oil heater coupled to the suction line and configured to heat oil passing through the suction line. Further, the system includes a return line coupled to the oil heater.

Abstract: A floating offshore structure includes a buoyant hull including a first column, a second column, and a pontoon coupled to the first column and the second column. Each column is vertically oriented and the pontoon extends horizontally from the first column to the second column. Each column has a central axis, an upper end, and a lower end. The pontoon includes a first tubular member and a second tubular member positioned laterally adjacent to the first tubular member. Each tubular member has a central axis, a first end coupled to the lower end of the first column, and a second end coupled to the lower end of the second column. The longitudinal axis of the first tubular member and the longitudinal axis of the second tubular member are disposed in a common horizontal plane.

Abstract: A method for constructing an FPSO comprises (a) assembling and integrating a plurality of modules to form a module assembly for installation on the FPSO. In addition, the method comprises (b) supporting the module assembly with one or more ballast adjustable pontoons. Further, the method comprises (c) positioning the module assembly over a deck of a vessel after (a) and (b). Still further the method comprises (d) de-ballasting the vessel and/or ballasting the one or more pontoons to load the module assembly onto the deck of the vessel after (c).

Abstract: A method for constructing an FPSO comprises (a) assembling and integrating a plurality of modules to form a module assembly for installation on the FPSO. In addition, the method comprises (b) supporting the module assembly with one or more ballast adjustable pontoons. Further, the method comprises (c) positioning the module assembly over a deck of a vessel after (a) and (b). Still further the method comprises (d) de-ballasting the vessel and/or ballasting the one or more pontoons to load the module assembly onto the deck of the vessel after (c).