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.

In a vessel and method for laying on the seabed a pipeline and one or more accessories which are to be connected to the pipeline, in particular in view of the installation of accessories to the pipeline, the one or more tensioners are displaceable along the pipeline launch tower.

In a vessel and method for laying on the seabed a pipeline and one or more accessories which are to be connected to the pipeline, in particular in view of the installation of accessories to the pipeline, the one or more tensioners are displaceable along the pipeline launch tower.

A turntable assembly for performing welding or other operations in a pivotably-mounted J-lay tower is disclosed. The assembly includes an annular turntable supported by a base frame to turn about a pipe string in use and a tilt-compensating mechanism acting on the base frame to level the turntable as the tower pivots in use. The tilt-compensating mechanism includes at least one support that is driveable up and down with respect to the tower. In the embodiment disclosed, the support is a carriage movable along an upright track that pivots with the tower.

A turntable assembly for performing welding or other operations in a pivotably-mounted J-lay tower is disclosed. The assembly includes an annular turntable supported by a base frame to turn about a pipe string in use and a tilt-compensating mechanism acting on the base frame to level the turntable as the tower pivots in use. The tilt-compensating mechanism includes at least one support that is driveable up and down with respect to the tower. In the embodiment disclosed, the support is a carriage movable along an upright track that pivots with the tower.

A field joint transfer system for transferring a hot field joint along a curved path between a tensioner and a stinger during deployment of a pipeline from a pipelay vessel. The system comprises a plurality of adjustable pipe support units defining a curved path between the tensioner and the stinger, wherein one or more of the pipe support units can be moved out of engagement with the pipeline to allow the hot fieldjoint to pass the respective pipe support unit without contact, while maintaining support for the pipeline along the curved path. A mobile pipe support may be provided on an overhead gantry to follow the pipe as it passes along the curved path.

A field joint transfer system for transferring a hot field joint along a curved path between a tensioner and a stinger during deployment of a pipeline from a pipelay vessel. The system comprises a plurality of adjustable pipe support units defining a curved path between the tensioner and the stinger, wherein one or more of the pipe support units can be moved out of engagement with the pipeline to allow the hot fieldjoint to pass the respective pipe support unit without contact, while maintaining support for the pipeline along the curved path. A mobile pipe support may be provided on an overhead gantry to follow the pipe as it passes along the curved path.

A method lays lined pipeline which actively and successfully removes air pockets which might be trapped in the annulus between the liner and the host pipe by progressively flooding the lined pipeline. Further, the liner is brought into closer contact and engagement with the host pipe. The removal of air in the annulus enables the pipeline test pressure to stabilize more quickly and avoids the risk of potential collapse during operational service life in the event the pipeline pressures fluctuate or a vacuum is created during an emergency shutdown.

A method lays lined pipeline which actively and successfully removes air pockets which might be trapped in the annulus between the liner and the host pipe by progressively flooding the lined pipeline. Further, the liner is brought into closer contact and engagement with the host pipe. The removal of air in the annulus enables the pipeline test pressure to stabilize more quickly and avoids the risk of potential collapse during operational service life in the event the pipeline pressures fluctuate or a vacuum is created during an emergency shutdown.

An offshore S-lay pipelaying vessel for laying a pipeline on the seabed, the vessel includes a hull and an elongated stinger having a hull end and a free end, the stinger being adapted to support the pipeline to be laid from the vessel. The stinger includes a stinger frame, possibly composed of one or more rigid stinger frame sections, possibly articulated sections. And, distributed over the length of the stinger, multiple pipeline support assemblies are mounted to the stinger frame that provide support for the pipeline.