A method for retrieving a pipeline from a seabed in the body of water to a vessel includes the steps of suspending at least a portion of the pipeline in the body of water between the seabed and the vessel, plastically deforming the portion of the pipeline to form a plastically deformed portion, and retrieving the plastically deformed portion to the vessel.

A method for retrieving a pipeline from a seabed in the body of water to a vessel includes the steps of suspending at least a portion of the pipeline in the body of water between the seabed and the vessel, plastically deforming the portion of the pipeline to form a plastically deformed portion, and retrieving the plastically deformed portion to the vessel.

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.

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.

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.

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.

A method including at least one phase of near-immobilization or immobilization of the line, including the following steps: activation of the motor of at least one upper tensioner and/or of at least one lower tensioner by a control unit, in order to apply to the movement member of the upper tensioner and/or of the lower tensioner, a holding torque to hold the line against its weight; at least occasional control by the control unit of at least one motor of an upper tensioner and/or of a lower tensioner for causing a movement member of the upper tensioner and/or lower tensioner to move or for changing the holding torque applied to the movement member of the upper tensioner and/or of the lower tensioner.

A method including at least one phase of near-immobilization or immobilization of the line, including the following steps: activation of the motor of at least one upper tensioner and/or of at least one lower tensioner by a control unit, in order to apply to the movement member of the upper tensioner and/or of the lower tensioner, a holding torque to hold the line against its weight; at least occasional control by the control unit of at least one motor of an upper tensioner and/or of a lower tensioner for causing a movement member of the upper tensioner and/or lower tensioner to move or for changing the holding torque applied to the movement member of the upper tensioner and/or of the lower tensioner.

A pipelay vessel having two pipe string manufacturing lines and a firing line, wherein the pipe string manufacturing lines are designed for simultaneously handling two different pipe outer diameters for use as an inner pipe and an outer pipe respectively. Further, the vessel has a pipe-in-pipe assembly workstation for assembling the inner pipe and the outer pipe in a pipe-in-pipe configuration. The vessel is designed with a lay-out which allows for producing offshore pipe-in-pipe strings from single joints, wherein available space is optimally used and pipe-in-pipe strings can be produced safely offshore.

A system for deploying a coil of spoolable pipe from a vessel includes a first tower configured to move longitudinally and transversely along a first track coupled to the vessel, a second tower configured to move longitudinally along a second track coupled to the vessel, and a coil drum assembly coupled to the first tower. The first tower is configured to insert the coil drum assembly transversely into an interior channel of the coil when the coil drum assembly is in a retracted position, the coil drum assembly is configured to support the coil when the coil drum assembly is in an extended position and rotate during deployment of the spoolable pipe, and the first tower and the second tower are configured to move the coil drum assembly vertically.