Abstract: A method of installing a subsea pipeline supports at least one elongate pipe stalk at the surface of the sea at a first, relatively shallow-water location by virtue of buoyancy added to the pipe stalk. The pipe stalk is then towed at the surface to a second location that is in deeper water. There, with the pipe stalk supported between leading and trailing towing vessels, at least some of the added buoyancy is removed. This causes the pipe stalk to hang with catenary curvature beneath the surface between the vessels. The catenary-curved pipe stalk hanging between the vessels is then towed to a third location for subsea installation, which may involve upending the pipe stalk before landing a lower end portion of it on the seabed.

Abstract: A pull-in head assembly (8) for releasably connecting a pulling arrangement (112) to an elongate flexible structure (4, 6). The pull-in head assembly (8) comprises a body (30) which defines a pulling axis X of the pull-in head and a retaining member (32) which is configured to secure the pull-in head assembly (8) to an elongate flexible structure (4, 6) such that a pulling force exerted on the body (30) along the pulling axis X is transferred to the elongate flexible structure (4, 6). The pull-in head assembly (8) is configured such that, in use, the body (30) and the elongate flexible structure (4, 6) are rotatable with respect to each other about the pulling axis X.

Abstract: A pull-in head assembly (8) for releasably connecting a pulling arrangement (112) to an elongate flexible structure (4, 6). The pull-in head assembly (8) comprises a body (30) which defines a pulling axis X of the pull-in head assembly (8) and a retaining member (32) arranged around the pulling axis X. The retaining member (32) is configured to secure the pull-in head assembly (8) to an elongate flexible structure (4, 6) such that, in use, a pulling force exerted on the pull-in head assembly (8) along the pulling axis X is transferred to the elongate flexible structure (4, 6). The retaining member (32) is configured to release the pull-in head assembly (8) from the elongate flexible structure (4, 6) when the pulling force exceeds a predetermined threshold such that the pull-in head assembly (8) can be separated from the elongate flexible structure (4, 6).

Abstract: A connection apparatus 10 for mounting a cable to a structure such as a wind turbine or oil rig. The apparatus 10 including a receiving member 14 having a hollow body with a diverging mouth, a latch member 22 movably mounted on the outside of the receiving member 14 with a latch part 24 extending into the receiving member 14. A mounting member 16 is provided which mounts the cable extending therethrough. The mounting member 16 is selectively locatable in the receiving member 14 with the latch part 24 engaging with a retaining formation in the form of a groove 56 to retain the mounting member 16 in the receiving member 14 and hence retain the cable mounted to the structure.

Abstract: A transfer mechanism (28) for transferring a fitting (46) on a flexible tubular conduit (48) about a guiding means (26) of a pipelay tower (20). The transfer mechanism (28) includes a frame (30) adapted to rotate about said guiding means (26); and a clamping mechanism (34) connected to the frame (30) and adapted to connect and secure the fitting (46) to the transfer mechanism (28). Actuation of the transfer mechanism (28) is configured to rotate the frame (30) about the guiding means (26) and cause at least one part of a fitting (46) connected to the transfer mechanism (28) to move along a path outside a surface of the guiding means (26) from a first position upstream of the guiding means (26) to a second position downstream of the guiding means (26).

Abstract: A hydraulic tool for moving a first structural element in the axial direction in relation to a second structural element. The tool comprises a ring-shaped frame configured for insertion into a gap between an annular shoulder on the first structural element and an annular shoulder on the second structural element; and hydraulic power members fixed to and distributed along said frame, the power members being configured to exert an axial pushing force against one of said annular shoulders to thereby move said structural elements apart. The frame comprises first and second arc-shaped sections, each of which having a hinged first end and an opposite second end. The arc-shaped sections are pivotable between an open position, in which their second ends are spaced apart, and a closed position, in which their second ends are in contact with each other.

Abstract: A method of handling a discrete elongate subsea element of determinate length, such as a spool of rigid pipe is disclosed. The method includes shortening a tensile chord system acting on longitudinally-spaced locations on the element to apply longitudinally-compressive forces to the element. The compressive forces bend the element along its length against elastic recovery force to shorten the span of the element. One end of the element is anchored at a first anchorage before or after the element is bent. The other end of the element is anchored at a second anchorage, after the element is bent and while the element remains bent. The method is apt to be used during installation of the element, where the anchorages are both underwater, and during transportation of the element, where the anchorages are hang-off platforms of a surface vessel.

Abstract: Disclosed is an apparatus for facilitating connection of a subsea flowline and a riser assembly so that the subsea flowline and the riser assembly can be jointly maneuvered in a subsea environment. A method and a system are provided in which the subsea flowline, the riser and the apparatus are connected. The apparatus includes a deployment skid having an integrated conduit having a 90° bend therein. One end of the conduit connects to a subsea flowline termination. A second end of the conduit is configured to receive the lower termination of the riser. The apparatus includes a coupling member configured to swallow and grasp the lower termination of the riser and the second end of the conduit. A pair of guide members, each guide member having an elongated slot along the length thereof, is pivotally connected at the base of the deployment skid and at the coupling member, one guide member on either side.

Abstract: A coupling device for connecting a first coupling housing (12) and a second coupling housing (20) is provided. The first coupling housing (12) comprises a guiding element (101; 201; 301a-e; 401b,c; 501b-d) extending from the first coupling housing (12) and having a free end (102; 202; P) at a distance (h) from the first coupling housing central axis (a-a). The second coupling housing (20) comprises a receptacle (123; 223; 323; 423; 523) for the guiding element and pull-in means (8) for pulling the guiding element into the receptacle, said pull-in means (8) being connected to the guiding element free end (102; 202; P). The invention allows the first coupling housing to be pulled towards the receptacle at an angle which is not coincident with the central axis (a-a), and when the guiding element is in place inside the receptacle, the first coupling housing central axis (a-a) and the central axis (b-b) of the second coupling housing are aligned and coincident, and the two housings are rotationally aligned.

Abstract: The invention relates to a marine pipelaying system comprising a vessel (1) provided with a pipeline launch tower (6). The tower (6) comprises pipe laying equipment defining a tower firing line, and is adapted for launching a pipeline (20) along the firing line into the sea. The system furthermore comprises a hang off module (15) supported in the lower part of the firing line for clamping and supporting the weight of previously launched pipeline (20) as well as a stinger for guiding the launched pipeline (20). The stinger (10) is supported at its upper end in the lower part of the firing line. The stinger is displaceable from the firing line.

Abstract: A method of laying a pipeline on the bed of a body of water includes constructing, on a laying vessel, a pipeline having pipe sections of a designated or given thickness, and thicker pipe sections distributed along the pipeline; moving the laying vessel forward and laying the pipeline in the body of water as the pipeline is constructed; and propelling a train, configured to plug the pipeline, in steps inside the pipeline laid on the bed of the body of water; the step travel of the train being related to the position of the thicker pipe sections, and to the touchdown point of the pipeline on the bed of the body of water.

Abstract: An underwater well is completed by extending an elongate stinger laterally outward from a vessel positioned at the water surface. The stinger is extended to curve downward toward a wellhead of the well. A well completion string is deployed from the vessel on the stinger while supporting the completing string to curve outward and downward from the vessel toward the wellhead. The completion string is then guided into the wellhead.

Abstract: The present invention relates to an accessory device which comprises a damping sleeve (100), which is coupled to a bend stiffener (4), capable of acting in the anchoring operation of a riser (3) so as to eliminate the need for fuse cables and safety straps, the need to use a team of divers, and to guarantee the implementation of the operation in all sea conditions.

Abstract: A bend restriction element (1) is modular for forming a tube segment (12) all around a conduit through locked inter-locking circumferential interconnection of multiple similar such elements (1). The tube segment (12) is modular for forming an articulated tube (100) around the conduit through locked interlocking longitudinal interconnection of multiple similar such tube segments (12). The locking of the circumferential interconnection of the elements (1) is ensured both by the manner of interlocking of a tube segment concerned (12) with a tube segment (16) situated on one side thereof, and by the manner of interlocking of the tube segment concerned (12) with a tube segment (14) situated on the other side thereof.

Abstract: A marine pipeline installation system is provided for laying a pipeline and/or installing a subsea riser. The system includes a pipeline guide supported at an elevated position by the tower for guiding the pipeline from a first trajectory extending between the reel and the pipeline guide to the firing line along said tower. The pipeline guide is supported by the tower via an associated guide support frame, the support frame being adapted to allow for displacement of the pipeline guide between a pipelaying position, wherein one end of the pipeline guide is positioned in the firing line, and a retracted, non-operable position. The guide support frame allows movement of the pipeline guide in a combined upward direction and direction towards the reel, such that in the retracted position of the guide support frame the length of the first trajectory is essentially the same as in the pipelaying position.

Abstract: Offshore deployment device for an installation vessel (4) with a deck (5) to deploy a hydrocarbon transfer pipe (2) composed of several pipe segments (3), the device including a trolley hoist lifting element (10), installed in a tower (6) to lift a pipe segment from an horizontal position into a vertical position, an assembly platform (8), where a segment is connected to a previously launched transfer pipe string, the assembly platform being provided with a clamping device that is supported on the installation vessel and adapted to support the weight of the previously launched pipe string during assembling, wherein the hydrocarbon transfer pipe is a flexible hose string composed of several flexible hose segments, the flexible hose string being guided from a vertical position into an inclined or a horizontal position via a hose string guide element (15) which is placed under the assembly platform.

Abstract: The present invention relates to apparatus for retaining at least one umbilical in relation to a string. The apparatus (30) comprises a body (32), first (38) and second members (40) and first (50, 52) and second fasteners. The body and the first member are movable in relation to each other between a first disposition, in which the body and the first member define a first bore (34) between them for accommodating a string, and a second disposition, in which the body and the first member are spaced apart from each other such that the string can be received in or removed from the first bore.

Abstract: Disclosed is an apparatus to be mounted on a vessel for laying a marine pipeline having accessories on the end of the pipeline and/or at one or more intermediate locations along the pipeline, the apparatus including a launch ramp having a guide for guiding and controlling the movement of a pipeline along a pipeline firing line in the direction of the seabed, a clamp downstream of the guide for selectively clamping and supporting the launched pipeline, wherein the launch ramp is provided with an opening downstream of the guide and upstream of the clamp for passage of an accessory between a storage position and an installation location in the pipeline firing line to allow the accessory to be connected to an end of the pipeline supported by the clamp.

Abstract: The method according to the invention comprises providing a flexible line (18) and a bend limiter axially immobilized around the flexible line (18) by a releasable immobilizing mechanism (46). It includes partially inserting the flexible line (18) through a hollow rigid member (40), immobilizing the bend limiter on the hollow rigid member (40), and deactivating the releasable immobilizing mechanism (46). The releasable immobilizing mechanism (46) is deactivated independently of the movement of the flexible line (18) relative to the bend limiter.

Abstract: Systems and methods are described for controlling axial, lateral and/or vertical movements of subsea pipelines which reduce the need for expensive pipeline anchoring or other mitigation solutions. The pipeline is connected to a stabilizing structure generally adjacent to the pipeline using a plurality of load-bearing members attached to the pipeline and the stabilizing structure at a plurality of predetermined locations. Also described are systems and methods for monitoring operating parameters of the pipeline over time.

Abstract: Apparatus for transferring oil between a first facility and a second facility. The apparatus comprises a pipe supported at one end by a floating buoy and decoupling arrangement to decouple movement of the buoy from a substantial portion of the pipe. The decoupling arrangement is generally arranged to support a portion of the pipe adjacent the floating buoy and may comprise, for example, a tether attached to the floating buoy, one or more diverter disks attached onto the length of pipe, a sliding connection or an arrangement of weights and buoys along the length of the pipe.

Abstract: A device includes a hollow rigid member (40) and a curvature limiter (42) movable relative to the hollow rigid member (40). A releasable device (46) for axial immobilization of the curvature limiter (42) on the flexible line (18) in at least one first direction along a travel axis (X-X?). The axial immobilization device (46) includes a locking member (90) axially secured to the flexible line (18), and a member (92) for fitting the locking member (90), axially secured to the curvature limiter (42). Those members (90, 92) are movable relative to each other around the travel axis (X-X?) between a configuration for axial immobilization of the flexible line (18) on the curvature limiter (42), and a configuration for axial travel of the flexible line (18) across the curvature limiter (42).

Abstract: An offshore riser system comprising a tubular from a sea floor to a sea surface comprising a first horizontal portion at the sea floor; a second vertical portion near the sea surface; and a third curved portion located between the first and second portions; and a buoyancy module connected to the second portion, adapted to maintain a shape of the curved portion and enable a connection of a vessel to the second portion.

Abstract: An accessory for a subsea pipeline such as an in-line tee having a rigid pipe support frame defining a pipe course and at least one carriage arranged to support a pipe or a fitting attached to a pipe. The carriage is movable with respect to the frame in a direction generally parallel to the pipe course. The carriage is attached to the frame via at least one angularly movable connection that allows a pipe or fitting supported by the carriage to tilt locally with respect to the frame as the pipe bends during laying. Pipe stiffness is therefore independent from the stiffness of the accessory. The stiffened section of the pipe is limited to a short length of the carriage. This is compatible with the small bending radius of the pipe on a stinger.

Abstract: A pipe-laying vessel including a pipe-laying tower extending upwardly from the vessel, the tower including a first lower section extending upwardly from a proximal end to a distal end above the main deck of the vessel, and a second upper section movably mounted on the first lower section, and the tower having a first pipe-laying configuration for laying pipeline P in which the upper section is positioned above the lower section and pipe is passed from the upper section to the lower section when, in use, it is being laid, and a second stowed configuration in which the second upper section is moved relative to the lower section and the overall height of the tower is reduced.

Abstract: A bending restrictor assembly for use with a pipeline section has a sleeve affixed to the pipeline section, an outer collar slidably positioned relative to and over the sleeve, and an inner collar slidably positioned relative to an interior of the outer collar. The inner collar in spaced longitudinal relation to an end of the sleeve. The inner and outer collars are slidable relative to a bending of the pipeline section. A series of holes and keyways are formed in the inner and outer collars. Pins are inserted into corresponding holes and keyways so as to correspond to a limit of the bending radius of the pipeline section.

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: An offshore system for drilling or production comprises a buoyant hull. In addition, the system comprises a topside mounted to the hull and positioned above the surface of the water. Further, the system comprises 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 system comprises a bend restrictor disposed about the conductor. The bend restrictor comprises a first sleeve having a lower end positioned in the sea bed below the sea floor, an upper end positioned above the sea floor, an inner surface extending between the upper end and the lower end, an outer surface extending between the upper end and the lower end, and a slit extending helically about the first sleeve. The slit extends radially from the inner surface to the outer surface of the first sleeve.

Abstract: The present invention relates to a pipeline guide assembly for a pipeline laying vessel, the pipeline guide assembly comprising:—a plurality of segments (20) pivotably interconnected via hinges (38) in an end-to-end relationship, each segment comprising at least one pipeline support (34) constructed to support a pipeline, wherein the pipeline supports provide a firing line (24) along which a pipeline can be launched,—a curvature mechanism (32) comprising at least one actuator (68, 68a, 68b, 68c, 68d), the curvature mechanism constructed for pivoting each segment relative to the next segment such that in use the segments provide a curved firing line, wherein the pipeline supports limit the curvature of the pipeline as it is launched along said curved firing line. The present invention also relates to a vessel comprising the stinger. The present invention also relates to a method of laying a pipeline utilizing the stinger of the invention.

Abstract: Disclosed is a method of laying pipeline in a horizontal plane. The method comprises anchoring a pivot member to a bed under a surface of a body of water; attaching a first plurality of lines to the pivot member; extruding a pipeline from a support base onto the surface of the body of water; and attaching a first line, of the first plurality of lines, to the extruded portion of the pipeline. Subsequently, the boat applies a force to the extruded portion applies such that the extruded portion of the pipeline encircles the pivot member while floating on the surface of the water, wound into a flat monolayer spiral. An inner radius of the spiral is sufficiently large to avoid applying plastic strain to the pipeline.

Abstract: A lay ramp for an underwater-pipeline laying vessel has an inside ramp hinged to the laying vessel; an outside ramp hinged to the inside ramp; and an actuating device having a first actuating assembly for rotating the inside ramp with respect to the laying vessel, and a second actuating assembly secured to the outside ramp and to the first actuating assembly to rotate the outside ramp with respect to the inside ramp.

Abstract: A method is disclosed for reeling or unreeling a pipeline having an inner corrosion-resistant metallic liner that is tightly fitted within the pipeline. To minimize or avoid wrinkling of the liner during the reeling or unreeling, a length of the pipeline is internally pressurized in a two-stage pressurizing process, and then the length of pipeline is reeled or unreeled, as the case may be. In the first stage of the pressurizing process, the length of the pipeline is filled with fluid at an elevated pressure, and in the second stage the fluid pressure is raised to a higher pressure, which may be 25 bars or more, absolute.

Abstract: A device and a method for lowering or raising the end of an undersea pipe between a vessel and the sea bottom by a carriage moving along an inclined J-lay tower and co-operating with chain-locking devices connecting the top end of the pipe to a storage area by passing over a deflector sheave secured to said carriage. A first chain-locking device is secured to the carriage and serves to lock the abandonment chain while lowering the carriage and the top end of the pipe at the end of the chain, a second locking device then being in an open position at the base of the tower. Thereafter, the abandonment chain is locked at the low portion of the tower with the help of the second chain-locking device, with the first chain-locking device being in the open position while the carriage is being raised.

Abstract: A bending restrictor assembly for use with a pipeline section has a sleeve affixed to the pipeline section, an outer collar slidably positioned relative to and over the sleeve, and an inner collar slidably positioned relative to an interior of the outer collar. The inner collar in spaced longitudinal relation to an end of the sleeve. The inner and outer collars are slidable relative to a bending of the pipeline section. A series of holes and keyways are formed in the inner and outer collars. Pins are inserted into corresponding holes and keyways so as to correspond to a limit of the bending radius of the pipeline section.

Abstract: The present invention relates to a marine pipeline installation system for laying an offshore pipeline and/or installing a subsea riser, said system being adapted to carry out the reel lay method and the J-lay method. The system comprises a vessel with a moonpool, a pipeline launch tower arranged on the vessel, a pipeline guide at an elevated position on said tower for guiding said pipeline to a pipeline launch trajectory along said tower, and one or more tensioners. The support assembly of at least one tensioner frame is adapted to allow for displacement of the tensioner frame between an active position, wherein the pipeline launch trajectory extends through the tensioner frame between the tracks, so that the tracks can engage on a pipeline, and a retracted and non-operable position. The system further comprises a J-Lay installation.

Abstract: A method and apparatus is disclosed for governing motion of a bend stiffener along a flexible pipe. The apparatus includes a stopper clamp secured to a portion of flexible pipe body and at least one retardation element located on the flexible pipe body at a predetermined position with respect to the stopper clamp. The retardation element is arranged to reduce momentum of a bend stiffener as it moves along the portion of flexible pipe body in a direction towards the stopper clamp.

Abstract: Flexible riser, comprising a length of a flexible pipe with an upper end, a bend restrictor and a termination for hanging up on a vessel, a floating installation or a platform, distinguished in that the bend restrictor in the upper end is connected to an adapter pipe extending from a lower end at the bend restrictor to an upper end, to an end coupling to which the upper ends of both the flexible pipe and the adapter pipe are fastened, the flexible riser extending through the bend restrictor and the adapter pipe and the end connection comprising a means for hanging up at deck level of the vessel, the installation or the platform. Method for pulling-in and hanging up of the flexible riser.

Abstract: The apparatus includes a tower (10) provided with tensioning apparatus (20) which suspends a pipeline being laid into the sea. The tower is mounted on a pivot in order to allow it to be inclined at an angle away from vertical to match the axis of the pipeline being laid. The apparatus also includes a hang-off clamp (22) and abandonment apparatus (36-42) for abandoning the pipeline to the seabed after laying. The abandonment apparatus can be operated independently in order to suspend or lower articles along an abandonment axis (B) which is spaced from the inclined pipeline laying axis (C). Also, the apparatus is capable of aligning the abandonment axis and the hang off clamp with one another while supporting the article. The clamp (22) is tillable into a stowed configuration, in which it is aligned with the longitudinal axis of the vessel.

Abstract: A marine pipeline installation tensioner comprising a tensioner frame and multiple track units mounted in said frame, wherein each track unit includes an endless track, a chassis, support rollers or other bearing means mounted therein for the endless track, and one more track drive/brake members for effecting drive and/or braking motion of the track, and wherein each track unit is arranged mobile within the associated frame. Each track unit is arranged mobile within the associated frame by a parallel linkage bar system with parallel linkage bars between the chassis of the track unit and the frame of the tensioner.

Abstract: An actuating device (23) for a lay ramp (6) of a vessel (1) for laying underwater pipelines “(2) has a runner (28), and a carriage (29) connected to the lay ramp (6) and which runs along the runner (28) to lift and lower the lay ramp (6); the runner (28) being defined by a first, a second, and a third portion (31, 32, 33), of which the first and third portion (31, 33) are out of line with respect to each other, and the second portion (32) is mounted on a movable assembly (37) to selectively align the second portion (32) with the first and third portion (31, 33).

Abstract: For regulating the lateral buckling of a section of pipe, at least one device permanently applies a force to a point on the section of pipe. The force is preferably applied substantially horizontally and perpendicular to the axis of the pipe. Preferably, two of the devices that apply equal and opposing forces are positioned at a distance from each other along the section of a pipe. Each device comprises a clamp, a cable, a return device and a buoy or a weight.

Abstract: A system for starting up a flowline suitable for conveying hydrocarbons is provided. The flowline is extended over the seabed from a wellhead and terminated at a joint end. The joint end is suitable for connection to a subsea riser extended in a catenary. The flowline is able to stretch and a lock fixes the joint end with respect to the seabed for maintaining the flowline in its stretched position, and preventing its return movement.

Abstract: Marine pipelaying method and system for installing an offshore pipeline (1) that includes one or more accessories (10). The method includes the steps of providing a vessel (2), launching the pipeline (1) in a firing line from the vessel (2) in the direction of the seabed, engaging the pipeline (1) with a clamping device (5b) that is connected to the vessel (2) and adapted to support the weight of the previously launched pipeline (1), and moving the accessory (10) into the firing line to a position above the clamping device (5b).

Abstract: A flowline for hydrocarbon which is capable of being reeled and which is unreeled for being laid on the seabed using the reeled lay method is comprised of successive pipe sections having opposing ends which are joined by an anchor collar that is butt welded to the opposing ends. The pipe sections have a jacket on the exterior of the pipe sections, but the pipe sections are able to be reeled. Anchor collars are affixed by butt welding between the ends of adjacent pipe sections. Each anchor collar has a fixture or protrusion radially outward which has an outer diameter less than or at least not more than the outer diameter of the pipe section jacket. The flowline has the same inner diameter at the pipe sections and the collar, and the pipe has the same outer diameter as the collar, while the protrusion protrudes outward from the exterior of the collar.

Abstract: A marine pipeline installation system for laying an offshore pipeline and/or installing a subsea riser, the system at least allowing to carry out the reel lay method, wherein the system comprises: one or more storage reels for storage of pipeline, a pipeline launch tower adapted for launching the pipeline in the direction of the sea, a pipeline guide at an elevated position for guiding said pipeline to a pipeline launch trajectory along said tower, one or more tensioners, each tensioner comprising a tensioner frame and multiple tracks supported by said tensioner frame, said tracks being adapted for engaging the pipeline and supporting at least part of the weight of the launched pipeline, the tensioner frame being supported by said tower via an associated support assembly.

Abstract: A method and system for storing, delivering and spooling pipelines, such as underwater pipelines used in off-shore well production systems, enables continuous pipeline reeling operations for multi-mile pipelines without the need for welding stops, a spool base of corresponding multi-mile length, a straight line path from storage to ship and/or stern mooring of the reel carrying vessel. Bending radii for the pipeline from welding to reeling are held to a determined minimum within the range of plastic deformation radii of the pipeline and preferably within the range of elastic bending radii of the pipeline.

Abstract: Controlled bending of a pipeline laying on the sea floor is achieved by attaching a bending sleeve assembly to a selected bending zone of the pipeline for limiting the controlled bending of the pipeline to a predetermined resulting bending configuration. External force is then applied on the bending sleeve assembly, bending the pipeline to the predetermined resulting bending configuration in cooperation with the bending sleeve assembly and the sea floor. External force can be exerted from one or more weights placed on top of the bending sleeve assembly. External force can be exerted from a winch attached to a wire, the wire passing through a pulley attached to a fixed structure, and the wire attached to the bending sleeve assembly. External force can be exerted through the bending sleeve assembly's contact reaction with an immobile object.

Abstract: A device and a method for lowering or raising the end of an undersea pipe between a vessel and the sea bottom by a carriage moving along an inclined J-lay tower and co-operating with chain-locking devices connecting the top end of the pipe to a storage area by passing over a deflector sheave secured to said carriage. A first chain-locking device is secured to said carriage and serves to lock the abandonment chain while lowering said carriage and said top end of the pipe at the end of the chain, said second locking device then being in an open position at the base of said tower. Thereafter, said abandonment chain is locked at the low portion of the tower with the help of said second chain-locking device, with the first chain-locking device being in the open position while the carriage is being raised.

Abstract: Sea water is extracted from a depth in excess of 400 meters below the sea surface and desalinated to produce potable water. A system to extract, desalinate and store the desalinated sea water is mounted aboard a ship.

Abstract: A bend-limiting conduit controls the curvature of a catenary riser extending from the seafloor as it enters the centerwell of a spar-type offshore platform through the keel of the platform. The conduit has a bore dimensioned to receive the riser, and it extends from an upper end constrained within the keel to a lower end disposed below the keel. The conduit has increasing flexibility and weight per unit length from the upper end to the lower end, which results in a lateral load being applied to the riser as it passes through the conduit, thereby causing a gentle and gradual transition in the riser from a curved configuration at the lower end of the conduit, to a straight configuration as it emerges from the upper end of the conduit.