A separation duct for encompassing an elongate member. The duct includes longitudinal internal spacers extend longitudinally in a direction of a longitudinal axis of the duct. A longitudinal plane for each spacer is substantially parallel to the longitudinal plane of the other spacers. The spacers support the elongate member and resist slippage of the duct relative to the elongate member. The duct may be used to provide separation and protection for elongate members of a range of outside dimensions.

A subsea pipeline system has a subsea pipe and a pipeline vibration damper (PVD) attached to the pipe.

A method of providing motion compensation of a subsea package with a synthetic rope comprising attaching the synthetic rope to the subsea package, supporting a first gripper with a wire rope from a winch capable of motion compensation control characteristics and gripping the synthetic rope with the first gripper, supporting a second gripper with a second wire rope, and repeating the following sequence: lowering the first gripper, the synthetic rope, and the subsea package a first distance, gripping the synthetic rope with the second gripper, releasing the first gripper from the synthetic rope, raising the first gripper the first distance, gripping the synthetic rope with the first gripper, releasing the second gripper from the synthetic rope, such that when the subsea package is lowered proximate the subsea landing location the winch capable of operating with motion compensation characteristics can operate to compensate for the vessel motion and smoothly lower the subsea package to the subsea landing location.

A reelable pipeline includes a pipe-in-pipe section and a single pipe section coupled to the pipe-in-pipe section. The single pipe section has a bending stiffness that is different from the bending stiffness of the pipe-in-pipe section. The reelable pipeline includes a transition piece connected between the pipe-in-pipe section and the single pipe section and having a bending stiffness that varies along its length.

A T-piece preformer for forming a T-piece in a pipe-in-pipe (PIP) pipeline for a marine environment, the PIP pipeline has at least inner and outer pipes having an annular space thereinbetween, and one or more cables extending along the annular space. The T-piece preformer includes at least: (a) inner and outer longitudinal collars; (b) annular walls between the inner and outer collars; (c) cable apertures through each annular wall; and (d) one or more guide points on the outer collar radially offset from the or each cable apertures, to guidance for a hole into the T-piece performer. The T-piece preformer can be assembled into a PIP pipeline, and requires a final hole during laying. The T-piece preformer has cable apertures through each annular wall, for allowing continuation of cables in the annular space through the PIP pipeline and T-piece preformer, and the T-piece.

The invention relates to a roller (10) which is to be mounted upon a conduit (12) to be deployed on the seabed. The roller facilitates lateral movement of the conduit. It is able to rotate relative to the conduit when mounted. The roller has an outer face (36) which contacts and rolls upon the seabed in use. The outer face is shaped to provide treads (38).

A method of installing an In-Line Structure (ILS) to a fluid-filled pipeline extending from a reel, over an aligner, and through a lay-tower during offshore reeling, the pipeline having an oblique part from the reel to the aligner, and a vertical part from the aligner through the lay-tower, including at least the steps of: (a) draining fluid in the fluid-filled pipeline from the vertical part of the pipeline to create a drained portion of the vertical part of the pipeline up to and around the aligner; (b) cutting the pipeline at or near the draining of step (a) to create upper and lower open ends of the pipeline; (c) installing the In-Line Structure to at least the upper open end of the pipeline; (d) locating a vent hose through a vent port in the In-Line Structure; (e) adding fluid into the drained portion of the pipeline and venting air from the drained portion of the pipeline through the vent hose to wholly or substantially fill the drained portion of the pipeline with the fluid.

A bend stiffener for resisting excessive-bending of an elongate underwater member in a region where it meets a rigid structure, comprises: a sleeve (1) for receiving said elongate underwater member, said sleeve being capable of some degree of flexure; and a rigid interface mount (3) secured to said sleeve, said rigid interface mount being suitable for attachment to said rigid structure; wherein said rigid interface mount comprises one or more slots (4) or holes which are alignable with corresponding slots, holes or recesses on said rigid structure such that the rigid interface mount may be locked to the rigid structure by locking means (2), said locking means comprising projection(s) through the slots or holes of the rigid interface mount into the slots, holes or recesses of the rigid structure. The bend stiffener is particular suited to mid-line applications, amongst other applications.

A cover that includes a deformable jacket, intended to be placed around the submerged element. The deformable jacket has an internal volume. The cover includes a plurality of insulating elements arranged in the internal volume, able to move freely relative to one another; at least one opening for selective access to the internal volume through the deformable jacket, for allowing the internal volume to be flooded by a liquid during the deployment of the cover towards the submerged element, and for allowing suction of the liquid contained in the internal volume during the application of the cover on the submerged element.

A line laying and/or recovering method in a body of water that includes providing a laying device including two facing upstream grippers and two facing downstream grippers, defining a passage for the circulation of the line; lowering the line to at least one stop position; stopping the line in the at least one stop position; and, prior to the at least one stopping of the line in the stop position, limited downward overrun past the stop position to a change of direction position; time delay in the change of direction position; limited raising of the line from the change of direction position to the stop position.