Abstract: An early production system includes an Emergency Disconnect Package (“EDP”), a production riser coupled between the EDP and a sea surface processing facility, a gas export tubing coupled between the EDP and the sea surface processing facility, and a flow base. The flow base is detachably connectable to the EDP. The flow base also includes an Independent Production Control System (“IPCS”) for controlling at least one production valve.

Abstract: A marine riser having a pressure level rating of twenty ksi or more includes riser tubulars and auxiliary lines that are made of steel having an API grade C110 and C125 and is NACE certified. The riser tubulars and auxiliary lines are not welded, but are assembled via threaded, clamped, stabbed or other mechanical and/or hydraulic connections. Some of the connections may be pre-assembled to reduce assembly time on the drill ship.

Abstract: A subsea production field has a subsea fortified zone that includes equipment designed to contain high pressure. The subsea production field also has a zone rated at lower pressure that includes equipment that is not capable of containing high pressure. A subsea pressure protection system is provided in the subsea fortified zone. The subsea pressure protection system includes a high integrity pressure protection system (HIPPS), and a pipe bundle. By selecting an appropriate length of the pipe bundle, the location of the separation between the subsea fortified zone and the zone rated at lower pressure may be kept fixed at the outlet of the pipe bundle.

Abstract: A pile top assembly includes an adapter configured to couple to an upper end of a subsea anchor, a tensioning system mounted on an upper end of the adapter, and a flexible tension member having a first end coupled to the tensioning system. The tensioning system is operable to pay in and pay out the flexible tension member relative to the tensioning system. The pile top assembly further includes means coupled to the adapter for selectively engaging the upper end of the subsea anchor.

Abstract: An offshore structure comprises a hull having a longitudinal axis, a first end, and a second end opposite the first end. In addition, the structure comprises an anchor coupled to the lower end of the hull and configured to secure the hull to the sea floor. The anchor has an aspect ratio less than 3:1. The hull includes a variable ballast chamber positioned axially between the first end and the second end of the hull and a first buoyant chamber positioned between the variable ballast chamber and the first end of the hull. The first buoyant chamber is filled with a gas and sealed from the surrounding environment. Further, the structure comprises a ballast control conduit in fluid communication with the variable ballast chamber and configured to supply a gas to the variable ballast chamber. The structure also comprises a topside mounted to the first end of the hull.

Abstract: A subsea production field has a subsea fortified zone that includes equipment designed to contain high pressure. The subsea production field also has a zone rated at lower pressure that includes equipment that is not capable of containing high pressure. A subsea pressure protection system is provided in the subsea fortified zone. The subsea pressure protection system includes a high integrity pressure protection system (HIPPS), and a pipe bundle. By selecting an appropriate length of the pipe bundle, the location of the separation between the subsea fortified zone and the zone rated at lower pressure may be kept fixed at the outlet of the pipe bundle.

Abstract: A pile top assembly includes an adapter configured to couple to an upper end of a subsea anchor, a tensioning system mounted on an upper end of the adapter, and a flexible tension member having a first end coupled to the tensioning system. The tensioning system is operable to pay in and pay out the flexible tension member relative to the tensioning system. The pile top assembly further includes means coupled to the adapter for selectively engaging the upper end of the subsea anchor.

Abstract: A system for offloading a fluid from an offshore structure comprises an annular conduit support structure disposed about the offshore structure. The support structure is fixably coupled to the offshore structure. In addition, the system comprises an annular reel disposed about the offshore structure and rotatably coupled to the support structure. The reel includes a conduit fairlead configured to move relative to the support structure. Further, the system comprises a flexible conduit having a fluid inlet end and a fluid outlet end. The flexible conduit includes a first portion wrapped around the conduit support structure and a second portion extending from the conduit support structure through the fairlead.

Abstract: A system for tethering a subsea blowout preventer (BOP) includes a plurality of anchors disposed about the subsea BOP and secured to the sea floor. In addition, the system includes a plurality of tensioning systems. One tensioning system is coupled to an upper end of each anchor. Further, the system includes a plurality of flexible tension members. Each tension member extends from a first end coupled to the subsea BOP to a second end coupled to one of the tensioning systems. Each tensioning system is configured to apply a tensile preload to one of the tension members.

Abstract: A pressure protection system includes a valve and a pipe bundle. A plurality of pressure sensors is coupled to the valve and communicatively coupled to a logic controller. The logic controller is operable to close the valve upon sensing a pressure above a predetermined limit. The pipe bundle includes a cylindrical coil of pipe that, in certain embodiments, may surround a riser or a wellhead.

Abstract: An offshore system for drilling or production includes a buoyant hull. In addition, the offshore system includes a topside mounted to the hull and positioned above the surface of the water. Further, the offshore system includes a conductor having a lower end disposed in the sea bed below the sea floor and an upper end coupled to the topside. Still further, the offshore system includes a bend restrictor disposed about the conductor. The bend restrictor has a lower end positioned in the sea bed below the sea floor and an upper end positioned above the sea floor.

Abstract: A system for tethering a subsea wellhead including a plurality of anchors disposed about the subsea BOP and secured to the sea floor. In addition, the system includes a plurality of tensioning systems. One tensioning system is coupled to an upper end of each anchor. Further, a plurality of flexible tension members. Each tension member extends from a first end coupled to the subsea wellhead to a second end coupled to one of the tensioning systems. Each tensioning system is configured to apply a tensile preload to one of the tension members.

Abstract: A system for tethering a subsea blowout preventer (BOP) includes a plurality of anchors disposed about the subsea BOP and secured to the sea floor. In addition, the system includes a plurality of tensioning systems. One tensioning system is coupled to an upper end of each anchor. Further, the system includes a plurality of flexible tension members. Each tension member extends from a first end coupled to the subsea BOP to a second end coupled to one of the tensioning systems. Each tensioning system is configured to apply a tensile preload to one of the tension members.

Abstract: An offshore structure comprises a hull having a longitudinal axis and including a first column and a second column moveably coupled to the first column. Each column has a longitudinal axis, a first end, and a second end opposite the first end. In addition, the offshore structure comprises an anchor coupled to the second end of the second column and configured to secure the hull to the sea floor. The first column includes a variable ballast chamber and a first buoyant chamber positioned between the variable ballast chamber and the first end of the first column. The first buoyant chamber is filled with a gas and sealed from the surrounding environment. The second column includes a variable ballast chamber. Further, the offshore structure comprises a topside mounted to the hull.

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 platform for offshore drilling and/or production operations comprises an equipment deck. In addition, the platform comprises a buoyant hull coupled to the equipment deck and configured to extend below the surface of the water. The hull comprises a first column having a central axis, an upper end coupled to the deck, a lower end distal the deck, and a plurality of axially stacked cells between the upper end and the lower end. Each cell defining an inner chamber within the cell and an exterior region outside the cell. The plurality of cells includes a first cell extending from the upper end of the first sub-column and a second cell axially positioned below the first cell. The first cell is water-tight. Further, the second cell includes a gas port configured to supply a buoyancy control gas to the inner chamber of the second cell.

Abstract: An offshore system for drilling or production includes a buoyant hull. In addition, the offshore system includes a topside mounted to the hull and positioned above the surface of the water. Further, the offshore system includes a conductor having a lower end disposed in the sea bed below the sea floor and an upper end coupled to the topside. Still further, the offshore system includes a bend restrictor disposed about the conductor. The bend restrictor has a lower end positioned in the sea bed below the sea floor and an upper end positioned above the sea floor.

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: Systems and methods for lifting drilling fluid from a well bore in a subsea formation are disclosed. Some system embodiments include a drill string suspended within a drilling riser to form the well bore, and a drilling fluid source for supplying drilling fluid through the drill string during drilling. A diverter is coupled between the drilling riser and a return line, while a power riser coupled to the return line at an interface. A lift fluid source supplies lift fluid through the power riser into the return line. The lift fluid is intermittently injected from the power riser through the interface into the return line to form one or more slugs of lift fluid positioned between slugs of drilling fluid, such that the combined density of lift fluid and drilling fluid in the return line is less than the density of the drilling fluid alone.

Abstract: A method for deploying a gas storage vessel below the surface of the water comprises coupling an upper end of the gas storage vessel to a deployment apparatus positioned at the surface of the water. The gas storage vessel has a total dry weight and a lower end opposite the upper end. The gas storage vessel also includes a storage tank defining an inner region inside the tank and an exterior region outside the tank. In addition, the method comprises lowering the gas storage vessel below the surface of the water with the deployment apparatus. Further, the method comprises pumping a buoyancy control gas into the inner region of the tank. The buoyancy control gas in the inner region of the tank generates a buoyancy force acting on the gas storage vessel.