A method for laying a pipeline on a seabed in order to provide controlled thermal expansion includes feeding the pipeline from a pipeline reel through a straightener system; and at the straightener system, imparting an alternating and continuously varying degree of residual curvature on at least a portion of the pipeline.

A method for laying a pipeline on a seabed in order to provide controlled thermal expansion includes feeding the pipeline from a pipeline reel through a straightener system; and at the straightener system, imparting an alternating and continuously varying degree of residual curvature on at least a portion of the pipeline.

A system for laying pipe includes a conveyor configured to receive one or more pipes, and one or more friction stir welding (FSW) machines configured to connect the one or more pipes to a pipeline deployed toward a sea floor.

A supporting device configured to support a pipeline on the bed of a body of water having a frame connectable in a sliding manner to a pipeline extending along a longitudinal axis between a laying vessel and the bed of a body of water; at least one floating body connected to the frame; and at least one connecting mechanism connecting the frame to the floating body and configured to define a distance between the axis of the pipeline and the floating body, so as to apply a torque to the portion of pipeline at the frame.

A supporting device configured to support a pipeline on the bed of a body of water having a frame connectable in a sliding manner to a pipeline extending along a longitudinal axis between a laying vessel and the bed of a body of water; at least one floating body connected to the frame; and at least one connecting mechanism connecting the frame to the floating body and configured to define a distance between the axis of the pipeline and the floating body, so as to apply a torque to the portion of pipeline at the frame.

A method has the following steps: a) providing an undersea foundation arranged on the bed of a body of water; b) laying a section of pipe and of an in-line structure on the foundation and allowing the section of pipe to freely self-orient on the foundation; c) placing at least one guide on the foundation on both sides of the section of pipe; d) blocking the guide on the foundation to laterally clamp the section of pipe with respect to the foundation, while authorizing a longitudinal movement of the section of pipe with respect to the guide.

The invention concerns a capstan reel (10) and a method for transporting an elongated article (6, 6a, 6b, 39, 42, 43, 45a, 47) between a floating vessel (2) and a body of water situated below the vessel, and a vessel applying such a capstan reel. The capstan reel comprises a rotatable cylindrical body (100) for spooling the elongated article around the body's axial axis (11), said body comprising a cylindrical contacting surface (35) for indirectly supporting at least a portion of the elongated article. Furthermore, the capstan reel comprises an endless chain (18) spooled at least partly around the cylindrical body in a helical direction relative to the axial axis of the body, acting as an intermediate layer between the cylindrical contacting surface and the intended elongated article, and a chain transfer guide (17) extending across the axial length of the cylindrical body for guiding the endless chain between a chain exit region (T) in a first axial end region (7a) of the cylindrical body and a chain entry region (E) in a second axial end region (7b), the second axial end region being situated at the opposite axial end of the cylindrical body.

A support for an underwater pipeline, in particular configured to elevate an underwater pipeline on a bed of a body of water, with a connecting frame configured to fit to a portion of underwater pipeline extending along a longitudinal axis; and at least two legs, which are hinged to the connecting frame, and movable between a contracted configuration and an extended configuration in which they extend crosswise to the underwater pipeline to rest on the bed of the body of water.

The invention concerns a process and a device for laying a subsea pipeline according to the J-lay or S-lay method wherein straight sections are mounted onshore, dried and degassed then closed by plugs. The sections are loaded on a pipe-laying ship, are separated from their plugs before the welding. At the welding of each bulkhead a short pumping is operated to reduce the pressure in the part of the annulus located between the two last bulkheads and then the opening leading to the annulus are sealed.

The invention concerns a process and a device for laying a subsea pipeline according to the J-lay or S-lay method wherein straight sections are mounted onshore, dried and degassed then closed by plugs. The sections are loaded on a pipe-laying ship, are separated from their plugs before the welding. At the welding of each bulkhead a short pumping is operated to reduce the pressure in the part of the annulus located between the two last bulkheads and then the opening leading to the annulus are sealed.