Abstract: A disconnectable mooring system for connecting an LNG carrier vessel to a permanently moored LNG liquefaction process vessel in combination with an LNG offloading system. One end of a mooring yoke is suspended from a frame at the stern of the LNG process vessel. A male coupler is mounted to an opposite end of the mooring yoke via a universal joint. A female coupler is mounted on the LNG carrier vessel, with pull-in arrangements for pulling the LNG carrier vessel into position and the male coupler into selective coupling with the female coupler.

Abstract: A disconnectable mooring system for connecting an LNG carrier vessel to a permanently moored LNG liquefaction process vessel in combination with an LNG offloading system. One end of a mooring yoke is suspended from a frame at the stern of the LNG process vessel. A male coupler is mounted to an opposite end of the mooring yoke via a universal joint. A female coupler is mounted on the LNG carrier vessel, with pull-in arrangements for pulling the LNG carrier vessel into position and the male coupler into selective coupling with the female coupler.

Abstract: An arrangement and method are disclosed for providing a fluid flow path between a seabed supply of hydrocarbons and a turret moored storage vessel. A steel catenary riser interface buoy provides support for a steel catenary riser and the lower end of a flexible riser. This arrangement allows both risers to be pre-installed prior to arrival of the storage vessel or other floating storage facility. A turret interface buoy, secured to an upper end of the flexible riser is used in the installation process as well as in the hook-up of the riser system to the storage vessel.

Abstract: In certain offshore locations, for example off the West Coast of Africa, FPSO facilities provide an offloading facility to receive and load produced crude oil onto shuttle tankers. In such arrangements FPSO facilities use spread moored tankers with flowlines suspended in the water column to an offloading buoy or buoys which are located 1,000 to 1,500 meters away from the FPSO. Typically steel pipe flowlines as used with intermediate floatation to provide a suitable configuration that will avoid detrimental loads being imposed resulting from relative motions of the FPSO and the offloading buoy. According to the invention, a Suspended Pipe Line End Manifold (SPLEM) is connected to the end of the flowline assembly for support during towout. The SPLEM is positioned near the buoy and then connected at the sea surface to the bottom of the buoy by flexible leads such as anchor chains. The SPLEM is then flooded by selectively flooding compartments to cause it to sink to an operational position below the buoy.

Abstract: A spread mooring arrangement is provided for use in deep water (greater than 200 meters) when it is advantageous to maximize the clearance between shuttle tankers used for product offloading and the anchor legs associated with a spread mooring of the permanently moored tanker. Mooring insert tubes are provided at the bow and stern of the vessel. Bow mooring lines extend from the sea floor, through an opening of the bottom of the hull of the vessel and via a bow mooring insert tube for securement on a chain pull-up deck. Stern mooring lines extend from the sea floor through an opening in the bottom of the hull of the vessel and via a stern mooring insert tube for securement on a chain pull-up deck.

Abstract: An improved vessel mooring system in which a storage vessel (10) weathervanes about a mooring base (16, 27) supported by the vessel for relative rotation. A plurality of flexible tubular dual function mooring lines (20) extend from the mooring base (27) to the sea floor (14) and thence to a subsea production facility (40). The dual function mooring lines (20) have collars (34) thereon which are anchored to the sea floor (14) by anchors (38). Product from a subsea production facility (40) is transported through the dual function mooring lines (20) to storage areas in the vessel (10).

Abstract: A riser buoy (36) supports a plurality of risers (19) and is releasably docked within a generally cylindrical turret (20) of a floating storage vessel (10) at a location above the sea level (12) to provide dry access to quick disconnect/connect mating couplings (32, 40) on the turret (20) and riser buoy (36). A weight (58) connected by anchor chain (44) to riser buoy (36) is connected at its upper end to a retrieval line (60) which is controlled by a winch (62). Riser buoy (36) upon disconnection from vessel (10) is positioned at a predetermined submerged water depth below tanker traffic and high wave loads. Riser buoy (36) is docked within turret (20) independently of positioning means such as anchor chains (17) between the sea bed and the turret, or a thrusting positioning system including thrusters (16) of the vessel.

Abstract: An improved detachable mooring system (1) is disclosed of the kind including a rotatable turret (10) mounted on the vessel (5) and a buoyant spider buoy (20), secured by chains (22) to the sea floor, which may be selectively connected by means of a hydraulic connector (209) to the bottom of the turret (10). One improvement relates to providing a roller bearing (598) between an upper part of the turret and an interior ring (56) of a well (50) of the vessel (50) at a level higher than sea water can reach under fully loaded conditions of the vessel. Such improvement provides an elastomeric pad (584) between the bearing (598) and a support ring (56) to reduce moment loads and to compensate for manufacturing tolerances of interface surfaces of the bearing (580, 586) and the support ring (56). Alternatively one or more spring stacks (791, 793) may be used rather than an elastomeric pad.

Abstract: An improved detachable mooring system (1) is disclosed of the kind including a rotatable turret (10) mounted on the vessel (5) and a buoyant spider buoy (20), secured by chains (22)to the sea floor, which may be selectively connected by means of a hydraulic connector (209) to the bottom of the turret (10). One improvement relates to providing a roller bearing (598) between an upper part of the turret and an interior ring (56) of a well (50) of the vessel (50) at a level higher than sea water can reach under fully loaded conditions of the vessel. Such improvement provides an elastomeric pad (584) between the bearing (598) and a support ring (56) to reduce moment loads and to compensate for manufacturing tolerances of interface surfaces of the bearing (580, 586) and the support ring (56). Alternatively one or more spring stacks (791, 793) may be used rather than an elastomeric pad.

Abstract: An improved detachable mooring system (1) is disclosed of the kind including a rotatable turret (10) mounted on the vessel (5) and a buoyant spider buoy (20), secured by chains (22) to the sea floor, which may be selectively connected by means of a hydraulic connector (209) to the bottom of the turret (10). The improvement relates to manufacturing the turret in three sections (10A, 10B, 10C), with top and bottom sections joined ultimately by a middle section. The top section (10C) includes a machined surface (102) for connection of the bearing retainer ring to the upper roller bearing (598). The bottom section (10A) includes a machined cylindrical journal surface (110) for connection to the radial support bearing. Another improvement relates to testing during manufacture of the mating and connection between the top of the spider buoy (20) and the bottom of the turret (10) prior to deployment of the vessel and spider buoy (20) in the sea.

Abstract: An improved detachable mooring system (1) is disclosed of the kind including a rotatable turret (10) mounted on the vessel (5) and a buoyant spider buoy (20), secured by chains (22) to the sea floor, which may be selectively connected by means of a hydraulic connector (209) to the bottom of the turret (10). One improvement relates to providing a roller bearing (598) between an upper part of the turret and an interior ring (56) of a well (50) of the vessel (50) at a level higher than sea water can reach under fully loaded conditions of the vessel. Such improvement provides an elastomeric pad (584) between the bearing (598) and a support ring (56) to reduce moment loads and to compensate for manufacturing tolerances of interface surfaces of the bearing (580, 586) and the support ring (56). Alternatively one or more spring stacks (791, 793) may be used rather than an elastomeric pad.

Abstract: A mooring system and method of anchoring a buoyant module (16) in a submerged location in the sea for supporting an underwater structure such as a plurality of acoustical arrays (18) for receiving and transmitting acoustical signals is disclosed. The buoyant module (16) is held in a submerged position by at least one anchor leg or line (46) anchored to the sea floor and of a variable length to permit controlled movement of the module (16) to the sea surface (10) for servicing. The single anchor line (46) is a stretchable line and includes an upper segment (56) formed of a Kevlar material and a lower segment (58) formed of a nylon material. Line 46 may stretch easily for a length of 400 feet, a preferred submerged depth of the module (16). Module (16) includes a constant buoyant material (36) and a source of compressed gas (32) controlled by a remotely actuated valve (40) to provide a variable buoyancy.

Abstract: The sealing apparatus is designed to automatically maintain the pressure of a buffer fluid above that of the sealed fluid. The apparatus consists of a cylinder (1) which has a movable piston (4, 5) therein. The piston (4, 5) is coupled to a valve shaft (8) and a first chamber (Z) in communication with sealed fluid is disposed on one side of the piston and a second chamber (Y) is on the other side of the piston for continuous communication with the buffer fluid. Recharging means in the form of a valve (12) and third chamber (X) which contains buffer fluid is a pressure greater than (Y) are associated with the second chamber (Y) so that in response to failure of seals the buffer fluid pressure drops in chamber (Y) and the pistons (4, 5) rise so that shaft mounted valve (12) is disengaged from valve seat (14) allowing high pressure buffer fluid to be transferred from chamber X to chamber Y.