Equinor Energy as

Statoil Asa

Technip Norge as

Erik Levold

Håvar Ilstad

Geir Endal

Kjell Einar Ellingsen

Bjørgulf Haukelidsæter Eidesen

Sven Morten Hesjevik

Per Egil Kvaale

Havar Ilstad

Marie Finstad Opgård

A method of connecting a conduit to a subsea structure is provided. In the disclosed method, a tensioning member is provided on the conduit and attached to the conduit at two locations proximate a first end of the conduit. The tensioning member is used to maintain a curvature formed in the conduit between the two locations e.g. by deflecting a portion of the conduit. A first end of the conduit is engaged with a guide assembly provided adjacent to the subsea structure, and tension in the tensioning member is released to adjust the axial position of the first end of the conduit to enable direct connection between the conduit and the subsea structure. A method of disconnecting a conduit from a subsea structure, and a system for connecting a conduit to a subsea structure are also provided.

Direct tie-in of subsea conduits and structures

There is provided a method of interconnecting a conduit and a plurality of subsea structures. The method comprises providing a first manifold header in-line of the conduit, where the first manifold header has at least one valve installed therein, A portion of the conduit is lowered to the sea bed such that the first manifold header is engaged with a first subsea structure, and a further portion of the conduit is lowered to the sea bed. A second manifold header, having at least one valve installed therein, is provided in-line of the conduit and engaged with a second subsea structure. The length of conduit provided on the sea bed between the first subsea structure and the second subsea structure is significantly greater than the distance between the first and second subsea structures.

Interconnection of subsea pipelines and structures

A pipeline comprising one or more pipes, the pipeline having: one or more sacrificial anodes to provide cathodic protection; one or more pre-formed one-piece integral metallic rings around at least one pipe; and one or more electrical connectors attached to the or each metallic ring and to at least one sacrificial anode to allow an electrical current to flow between the pipeline and one or more of the sacrificial anodes. Each metallic ring has a one-piece form and can be fitted to the pipe without welding.

Pipeline and methods

Method for laying a pipeline onto a seabed from a lay barge, the pipeline having an inner corrosion proof metallic cladding that is closely fitted with metallic contact to an outer pipe material that is less corrosion proof. The method includes reeling a section of the pipeline onto a pipe laying drum, while an overpressure of 5-25 bar is maintained within the section by a pressurized fluid inside the section, b) joining a further pipeline section to the section already reeled onto the pipe laying drum, while the pipeline is motionless without mechanical movement, as the overpressure can he relieved as long as the sections are without mechanical movement, c) applying an overpressure of 5-25 bar within the sections and the further section is reeled onto the pipe laying drum, d) and joining several sections together and reeling the joined sections onto one or several pipe laying drums by repeating step b) and c) until the predetermined pipeline length is achieved. The pipeline is laid from the lay barge onto the seabed using a conventional method, while an overpressure of 5-25 bar is maintained within the pipeline by means of a pressurized fluid until the pipeline is correctly placed onto the seabed.

Method for laying a pipeline having an inner corrosion proof cladding

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Trondheim, Norway

Erik Levold