Abstract: Methods and systems are described for monitoring the integrity of a subsea pipeline network to transport the production fluid from a subsurface wellhead to surface facilities. More specifically, the described methods and systems are for monitoring the integrity of a riser pipe network and can include installing one or more inclinometers to the buoyancy tank and/or vertical riser structures.

Abstract: Systems and methods are described for monitoring displacement on structural elements of subsea systems such as on components of a subsea pipeline network used to transport production fluid from a subsurface wellhead to surface facilities. The described techniques sense changes in displacement using a sensing blade, for example made of crystalline material such as sapphire, that is anchored to the structural element such that it is approximately perpendicular to the direction of sensed displacement. Displacement is sensed as bending of the sensing blade using one or more instruments fabricated on the blade. Robustness of design is in part provided by additional flexible non-sensing blades mounted in parallel to the sensing blade.

Abstract: Systems and methods are described for non-invasively acoustically monitoring containers to distinguish gas contents from liquid contents. In some embodiments the container is part of a buoyancy tank (132) in a subsea pipeline network (102) used to transport production fluid from a subsurface wellhead (112) to surface facilities, and the systems and methods are used to detect water ingression into the buoyancy tank (132) and to transmit alert signals to the surface relating thereto.

Abstract: Systems and methods are described for monitoring displacement on structural elements of subsea systems such as on components of a subsea pipeline network used to transport production fluid from a subsurface wellhead to surface facilities. The described techniques sense changes in displacement using a sensing blade, for example made of crystalline material such as sapphire, that is anchored to the structural element such that it is approximately perpendicular to the direction of sensed displacement. Displacement is sensed as bending of the sensing blade using one or more instruments fabricated on the blade. Robustness of design is in part provided by additional flexible non-sensing blades mounted in parallel to the sensing blade.

Abstract: Methods and systems are described for monitoring the integrity of a subsea pipeline network to transport the production fluid from a subsurface wellhead to surface facilities. More specifically, the described methods and systems are for monitoring the integrity of a riser pipe network and can include installing one or more inclinometers to the buoyancy tank and/or vertical riser structures.

Abstract: A system and method for monitoring bending curvature of a flexible pipe structure, including at least one conduit configured to conform to a profile of a bend stiffener of a flexible pipe structure, and the at least one conduit including one or more sensors, wherein each sensor is configured for measuring a bending curvature of the bend stiffener.

Abstract: A pipeline alignment termination device comprises a connecting piece (22, 24, 28) connected at its first end to a pipeline (29). The connecting piece is supported on a skid base (12) by an articulated support (24). Adjustable constraints (25, 26, 30, L) operable by ROV, permit the second end (20) to be accurately aligned by transverse and rotational adjustments with the end of a spoolpiece (232, 234). After alignment and connection, constraints on the rotation and transverse movement are removed, leaving the connecting piece supported but free to move with up to five degrees of freedom.

Abstract: Apparatus and methods for integrating a fiber optic cable (116) with a pipeline (104) are described. An example pipeline having an integrated fiber optic cable includes a plurality of pipe sections (119a, 119b), where each of the pipe sections has a thermally insulating outer layer (200, 202) and ends not covered by the outer layer. The ends of each of the pipe sections are welded to respective ends of other pipe sections to form field joints (111a) at the welded ends. The pipeline also includes a fiber optic cable, where first portions (120) of the fiber optic cable are in contact with some of the pipe sections at some of the field joints and where second portions of the fiber optic cable between the first portions are fixed to the outer layer. A coating is applied to cover each of the first portions of the fiber optic cable to integrate the fiber optic cable with the pipeline.

Abstract: A pipelay vessel has a stinger extending along and outboard of one side of the vessel. A diverter is arranged to lead pipe onto the stinger input end through a predominantly horizontal diversion angle from a pipeline source having a substantially horizontal orientation. The vessel is selectively operable in any one of three modes, namely: (1) shallow S-lay, in which the pipe is launched over a stern-mounted stinger with a launch angle which has a predominantly horizontal component; (2) steep S-lay, in which the pipe is launched over the side-mounted stinger with a launch angle which has a predominantly vertical component; and (3) J-lay, in which the pipe is welded at and launched from a tower. The axis of the J-lay apparatus is aligned with the departure axis of the side-mounted stinger.

Abstract: A system and method for monitoring bending curvature of a flexible pipe structure, including at least one conduit configured to conform to a profile of a bend stiffener of a flexible pipe structure, and the at least one conduit including one or more sensors, wherein each sensor is configured for measuring a bending curvature of the bend stiffener.

Abstract: A pipeline alignment termination device comprises a connecting piece (22, 24, 28) connected at its first end to a pipeline (29). The connecting piece is supported on a skid base (12) by an articulated support (24). Adjustable constraints (25, 26, 30, L) operable by ROV, permit the second end (20) to be accurately aligned by transverse and rotational adjustments with the end of a spoolpiece (232, 234). After alignment and connection, constraints on the rotation and transverse movement are removed, leaving the connecting piece supported but free to move with up to five degrees of freedom.

Abstract: The relative position and orientation between two subsea structures (210, 212) are measured by ultra-short baseline acoustic metrology. Dual mode master/slave (220, 222) stations comprising a multi-transducer array are fitted in known position and orientation relative to each structure. The first station (220) is operated in master mode to determine the position and direction of the second structure (222) relative to the first (220). The second station (222) is operated in master mode to determine the position and direction data from both operations the apparatus calculates relative position and orientation between the structures. The dual mode stations can be replaced by a master station and a slave station, swapping places.

Abstract: A fibre rope is used for hoisting articles from a vessel (12) in deep waters. The fibre rope has substantially neutral buoyancy. The rope (14) is handled in vertical orientation by a track type tensioner (18) or moving clamps, in order to avoid bend cycling under load.

Abstract: There are disclosed methods of and apparatus for interconnecting lined metal pipes (110, 120), applying in particular to the offshore oil and gas industry. Corrosion is a common problem in the industry. Lining pipes overcomes the problem, but welding sections of pipe together can be a complicated and time-consuming task, requiring dedicated and sophisticated tooling. More desirable is the ability to use conventional pipe-laying equipment (20, 40, 50, 60, 70, 80, 90) with little additional tooling. As such, there are disclosed methods and apparatus compatible with known offshore connection methods, particularly where the spacing of joints on the pipe is less than 100 m. The chosen technique will not significantly impact the laying rate of the lined pipe, compared with unlined pipe.

Abstract: A suction anchor (10) comprising a caisson (12) with side wall (14), open bottom (22) and closed top (26) that define the interior volume if the caisson. When the anchor is placed on a seabed (100) of fluent mud, a top connector (28) allows temporary connection of a pump (200) to suck seabed mud (102) through the open bottom into the caisson's interior, the bottom edge (20) of the caisson wall (14) allowing the anchor to cut into, and become embedded within the seabed (100). To increase resistance of the embedded anchor (10) from being withdrawn, the caisson is internally fitted with a seabed soil retaining means (30) that receives and retains mud during anchor embedment. The seabed soil retaining means comprises an open-topped container secured within the caisson, the open top (38) being located just below the caisson's closed top (26).

Abstract: The invention relates to a production riser system wherein the riser (1), at the touchdown point (5), has a bottom flexjoint (8) so that the dynamic motion of the riser (1) is absorbed by angular excursion (9) of the flexjoint (8) and not by the interaction of the sag bend (10) with the seabed (6). The surface end of the riser may be fixed, or coupled by a second flexjoint to a production and storage vessel.

Abstract: A method for transporting petroleum products in deep water from the seabed up to a floating or semi-submersible surface structure wherein at least one rigid and straight hybrid riser extends vertically. The hybrid riser has a rigid central hollow tubular structure surrounded by a cylindrical block of syntactic material which provides buoyancy and thermal insulation for the riser. A plurality of rigid pipelines are embedded in the syntactic material and surround the central tubular structure for receiving petroleum products from wells on the sea bed. The bottom of the riser is connected to a suction or gravity anchor at the sea bed. A submerged float is attached to the top of the riser and exerts an upward vertical force thereon. Flexible pipelines connect the rigid pipelines in the riser to the floating or semi-submersible structure.

Abstract: A device for transporting petroleum products in deep waters from the seabed up to a floating or semi-submersible surface structure wherein at least one rigid and straight hybrid riser extends vertically. The hybrid riser has a rigid central hollow tubular structure surrounded by a cylindrical block of syntactic material which provides buoyancy and thermal insulation for the riser. A plurality of rigid pipelines are embedded in the syntactic material and surround the central tubular structure for receiving petroleum products from wells on the sea bed. The bottom of the riser is connected to a suction anchor at the sea bed. A submerged float is fixed to the top of the riser and exerts an upward vertical force thereon. Flexible pipelines connect the rigid pipelines in the riser to the floating or semi-submersible structure.