Abstract:
A method of abandoning a pipeline during subsea pipelaying from a pipelay vessel (28) comprises suspending the pipe string (38) from a tendon element (36) of an abandonment string and engaging further tendon elements (36) to an upper end of the abandonment string while lowering the pipe string (38) to a handover depth. At the handover depth, tension is applied via a wire (48) to the top of the pipe string (38) at an acute angle to the launch axis. This deflects the pipe string (38) from the launch axis into axial alignment with the wire (48) to transfer the weight load of the pipe string (38) to the wire (48), whereupon the abandonment string can be decoupled from the pipe string (38). Recovery of the pipeline from the seabed can be effected by a reverse process.
Abstract:
Die Erfindung betrifft eine Anordnung (1) zur Übertragung von elektrischer Energie mit einer elektrischen Einrichtung (3), die unterhalb der Oberfläche (9) eines Gewässers (5) und oberhalb des Grundes (7) des Gewässers angeordnet ist.
Abstract:
A riser assembly and method of supporting a riser assembly are disclosed. The riser assembly includes a riser;at least one buoyancy compensating element attached to the riser; and at least one damped biasing element for controlling movement of the riser about a neutral position with respect to an adjacent underwater structure. The biasing element is directly or indirectly connected to the riser and is directly or indirectly connectable to the adjacent underwater structure.
Abstract:
A flexible pipe body and method of producing a flexible pipe body are disclosed. The method includes providing two or more non- bonded composite filaments (302) as a non-bonded filament bundle (310); applying a braid element (304) around the filament bundle (310) to thereby form a braided bundle (310) comprising non-bonded filaments (302); and helically wrapping the braided bundle (310) around a flexible pipe body layer (502).
Abstract:
The invention relates to an undersea installation for transporting hydrocarbons between a seabed and a surface and to a method for installing same. The installation comprises a tubular undersea pipeline, a float (14) and a coupling device (10). Said undersea pipeline has a rising part (16), a connecting part (18) and an intermediate portion (20). Said coupling device (10) comprises a first longitudinal part (24) and a second part (25) connected in a coupling region (37) of said first part (24), said coupling region (37) of said first longitudinal part and said float (14) being adapted to be connected together. Said first part (24) is adapted to pivot about said coupling region (37) while bending said intermediate portion (20) when said rising part (16) is unwound and tilts towards said seabed.
Abstract:
A method for providing a pipeline connection between two points at sea is described. A pipeline (1) floating in the sea is suspended between two spaced-apart points of support (3, 4) in the sea by means of a torque-free connection and is made to hang at such a depth between the two points of support (3, 4) that wave stresses are eliminated or will be reduced to an acceptable level. The pipeline (1) is tension-loaded via the points of support (3, 4). A transport arrangement comprising a pipeline connection between two points at sea is also described. The pipeline connection comprises a pipeline (1) which is suspended under an external tensile load and by means of a torque-free connection from two spaced-apart, submerged buoys (3, 4).
Abstract:
La présente invention a pour objet un dispositif de transfert de fluide entre deux supports flottants (2, 3) ancrés au fond de la mer (5) comportant une conduite sous-marine rigide centrale (1) installée en subsurface, dont les extrémités (la, Ib) sont reliées chacune respectivement à un des deux dits supports par l'intermédiaire d'une conduite flexible (11, 16), dans lequel a) la partie courante de ladite conduite rigide centrale (1) comprend ou coopère avec des éléments de flottabilité (8) de sorte que la dite conduite rigide centrale (1) adopte en état quasi-statique de repos une configuration en forme d'arche, de préférence selon une courbe sensiblement en forme de chaînette telle que les angles ((X1, OC2) entre les demi-droites des axes (XX', YY') de la dite conduite rigide et les demi-droites horizontales à chacune de ses extrémités (la, Ib) en direction de l'autre extrémité (Ib, la), sont en valeur absolue inférieurs à 20°, de préférence inférieurs à 15°, et b) les dites conduites flexibles (11, 16) ont des longueurs et courbures, de sorte que les variations de courbure des dites conduites flexibles sont aptes à compenser les mouvements des supports flottants.
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). Then the accessory (10) is connected to the pipeline (1) above the clamping (5b) device while the pipeline (1) is held by the clamping device (5b) Follow that the accessory (10) and the launched pipeline (1) connected thereto and releasably secured to a controlled load hoisting device (5) and the weight of the accessory (10) and the launched pipeline (1) connected thereto are transferred from the clamping device (5b) to the controlled load hoisting device (5) while the accessory (10) and the launched pipeline (1) connected thereto remain in the firing line. Finally the clamping device (5b) is disengaged from the pipeline (1) and moved away from firing line. Then the accessory (10) and the launched pipeline (1) connected thereto are lowered along the firing line by the controlled load hoisting device (5).
Abstract:
The invention relates to a subsea pipeline system (1) for connecting two hydrocarbon production, storage and/or processing structures. The subsea pipeline comprises a first duct section (2) supported on the seabed (4), a bridging duct section (6) extending across a lower seabed part (5), at a distance from the sea bed, and a second duct section (3) supported on the sea bed, the first and second duct sections being connected to the bridging duct section via an articulation joint (7, 8) allowing movement of the bridging duct section (6) in a length direction (L) of the first and second duct sections, wherein a first tensioning element (12, 37, 41) is with a first end (14) connected to the bridging duct section (6) at or near the articulation joint (7) and with a second end (15) to a lifting structure (9, 36) which is located at a relatively short distance above the bridging duct section (6), for exerting an upward force thereon, and a second tensioning element (19, 30, 38) connected with one end to the bridging duct section (6) and with the other end to a downward pulling structure (17, 31, 39), which is located below the bridging duct section (6), the first and second tensioning elements (12, 19, 30, 37, 38, 39, 41) including a mutual angle (a) such as to exert a horizontal pulling force on the bridging duct section.
Abstract:
The invention concerns a device limiting propagation of deformation in a wound double-walled tube (1). Said device comprises an outer wall (3) having a specific external diameter (D) and arranged around the inner wall (2), an annular space (5) being provided between said outer and inner walls. The device is characterised in that it consists in providing predetermined zones (7) in said annular space (5), each predetermined zone (7) being delimited between two sealing stop elements (9) whereof the radially opposite surfaces are in contact with the internal and external tubes; providing a hardenable compound (6) in each predetermined zone (7), the length (L) of each predetermined zone (7) being not less than 0.5 times the external diameter (D) of the outer shell (3).