A high pressure swivel system provides fluid communication on a turret-moored vessel between a swivel core member being in fixed rotational alignment with a seabed mooring system and a swivel revolving member being in fixed rotational alignment with the hull of the vessel. The revolving member has upper and lower radially extending surfaces. On each of the radially extending surfaces are a series of radially spaced apart pressure seals. Hydraulic barrier fluid pressure is regulated in each of the volumes formed between the pressure seals. The pressures in the volumes are regulated such that a process fluid pressure higher than could be tolerated by any one individual pressure seal is safely accommodated by sharing the high process fluid pressure between or among two or more of the radially spaced apart pressure seals.

A buoy device includes a first part having a first support structure and a second part having a buoyant body and a second support structure. The first and second support structures are connectable to form a rotatable connection between the first part and the second part. The buoyant body further includes one or more buoyancy elements releasably arranged on the second part. The buoy device may be a turret buoy, a CALM turret buoy, or a CALM turntable buoy.

Systems and processes for recovering condensate from a conduit. The system can include a buoy that can include a fluid swivel assembly. The system can also include a first surface conduit and first and second gas transfer conduits that can be in fluid communication with the fluid swivel assembly and configured to transfer a gas discharged from a vessel storage tank to a gas pipeline. The system can also include first and second liquid transfer conduits in fluid communication with the fluid swivel assembly and configured to transfer a liquid from a liquid pipeline to the vessel storage tank. The system can also include a condensation conduit configured to transfer at least a portion of any condensate that accumulates within an internal volume of the first surface conduit or the first gas conduit into a fluid flow path defined by the fluid swivel assembly or the second liquid transfer conduit.

A petroleum drilling, production, storage and offloading vessel having a hull, a main deck, an upper cylindrical side section extending downwardly from the main deck, an upper frustoconical side section, a cylindrical neck section, a lower ellipsoidal section that extends from the cylindrical neck section, and a fin-shaped appendage secured to a lower and an outer portion of the exterior of a bottom surface. The upper frustoconical side section located below the upper cylindrical side section and maintained to be above a water line for a transport depth and partially below the water line for an operational depth of the petroleum drilling, production, storage and offloading vessel.

A mooring connector assembly (3) has a body (10) arranged to be pivotally mounted to a structure (1), such as a tethered buoy, to be moored for movement about a pivot axis. At least a part of the body extends below the pivot axis when so mounted and oriented for use. A line stopper (17) is mounted to the part of the body which extends below the pivot axis in use and is operative to retain a mooring line (2) relative to the body. The body is configured to receive a tensioner (20) for tensioning a mooring line (2) retained by the stopper such that the tensioner urges the line at a point which is below the pivot axis when the body is oriented for use. The body may be an elongate tube (10) pivotally connected to a structure to be moored (1) at one end and fitting with a chain stopper (17) at the opposite end. The tube is configured to receive a chain tensioner (20) between the chain stopper (17) and pivot axis.

An offshore production and storage system includes a spread moored buoy assembly including a riser buoy coupled to a mooring buoy, the riser buoy configured to receive and couple to risers, wherein the spread moored buoy assembly is configured to be pre-installed offshore with the risers coupled thereto, and wherein the spread moored buoy assembly is configured to couple to a floating vessel such that the risers fluidicly couple to the floating vessel via the riser buoy.

Techniques and systems to reduce deflection of a riser extending from offshore platform. The riser may be coupled to a seafloor and may experience movements due to, for example, currents. A riser restraint device may be utilized to reduce these movements of the riser. This riser restraint device may be coupled to the seafloor. This coupling of the riser restraint device may aid in allowing the riser restraint device to reduce movement of the riser and, thus, reduce deflection of the riser.

Offloading cargo from a cargo vessel and delivering the cargo to a cargo recipient, or loading cargo onto the cargo vessel from a cargo supplier, may be performed using a cargo vessel which is spread moored at sea to a plurality of mooring points for mooring the cargo vessel in a desired orientation. Alternatively, the cargo vessel may be rotatably moored. Tubing may be provided and configured to be connected to the vessel for fluid communication between the vessel and the cargo recipient or the cargo supplier, and may comprise a first portion configured to be connected to the cargo vessel and a second portion configured to be connected to the cargo recipient or the cargo supplier. A semi-submersible unit may be operable to travel across the sea and carry part of the tubing from a stand-by location to a position adjacent to the cargo vessel, so as to allow an end of the first portion of the tubing to be connected the cargo vessel for offloading or loading the cargo. The unit may have at least one lifting and handling device, which when the unit is positioned adjacent to the cargo vessel, may be operable for arranging the end of the first portion of the tubing at or near a manifold on the cargo vessel for connection thereto.

A mooring assembly includes: a mooring buoy having a central axis, an upper ring portion providing an upper abutment surface; a mooring structure including a cavity with a wall receiving the mooring buoy; and a buoy locking system near the cavity engaging with the upper ring portion for locking the mooring buoy to the turret mooring structure and including at least two locking devices attached to the mooring structure, each locking device having a locking dog connected to a force member for axial displacement and exerting an upward force on the upper abutment surface. The mooring buoy includes a lower abutment surface. The locking system includes an engagement member below the locking dog, engaging with the lower abutment surface and exerting a downward force. The buoy at positions axially above the upper abutment surface situated at an axial clearance from the cavity wall.

A buoy accomplishes a fluid connection between a vessel on a water surface and a subsea template located on a seabed via at least one riser. A fluid is transported by the fluid connection from the vessel to the subsea template, and the fluid is injected from the subsea template (120) into a subterranean void via a drill hole. At least one valve in the buoy is controllable from an external site in response to commands so as to shut off the fluid connection from the vessel to the at least one riser.