Abstract: A hoisting assembly for lifting or lowering a heavy object includes an upper fixed block, an upper movable block being suspended from the upper fixed block by at least one first rope which is reeved into one or more first rope lengths between the upper fixed block and the upper movable block, a lower movable block being connected to the upper movable block by at least one second rope which is reeved into one or more second rope lengths between the upper fixed block and the upper movable block. The first and second ropes are reeved in such a way that in use the upper movable block can be positioned at a distance greater than zero from the upper fixed block and at a distance greater than zero from the lower movable block by controlling the lengths of the first and second ropes.

Abstract: The present invention relates to a pipe section (10), constructed to be joined end-to-end to a same pipe section in order to form a pipeline which is laid from a pipeline laying vessel, the pipe section having a pipe has a greater wall thickness than the wall thickness of a main part of the pipe wall (15), the pipe section comprising a thickened gripping zone (20) which section, wherein the thickened gripping zone has a length (22) and a wall thickness which are constructed and arranged to allow a shear clamp (45) having protrusions (48) to grip the thickened gripping zone in order to suspend the pipeline from the pipeline laying vessel via the thickened gripping zone.

Abstract: A pipeline laying vessel (1) for laying a pipeline (2) on a seabed, said vessel (1) comprising a J-lay system (4) defining a firing line (5) along which the pipeline (2) is laid, the J-lay system (4) comprising an alignment device (6) for aligning a pipe section (7) with the pipeline (2) suspended from the J-lay system (4) with a sufficient level of accuracy to allow the pipe section (7) to be welded to the pipeline (2), the alignment device (6) being constructed to maintain the alignment during at least a part of the welding operation of the pipe section (7) to the pipeline (2), wherein the alignment device (6) is movable between a first position (10) in the firing line (5) and a second position (11) outside the firing line (5), and the alignment device (6) is constructed to engage a pipe section (7) in the second position (11) and to be moved into the first position (10) together with the engaged pipe section (7).

Abstract: A method for constructing a riser assembly (1) for transporting a fluid from a vessel and on a seabed includes providing an elongate frame (4) having a first frame end (5) and a second frame end (6), where the first frame end is connected to the seabed (3) and the second frame end is connected to a buoy (7), providing at least one riser (9) for transporting a fluid, and connecting the at least one riser to the second frame end and/or the buoy.

Abstract: The present invention relates to a vessel comprising:-a hull,-a support structure connected to said hull, the support structure configured for supporting the mass, the support structure being constructed to allow the mass to make a back and forth movement relative to said hull along a trajectory between opposite ends of said trajectory,-a damping device configured to dampen the movement of the mass relative to said hull. The present invention also relates to a method for damping the movements of a vessel or of a mass.

Abstract: A pipeline laying vessel for laying a pipeline (5) on a seabed, which pipeline laying vessel comprises a hull, a positioning device (6) for positioning a pipe section in a firing line (3) along which the pipeline is laid, which positioning device is supported by the hull, and a clamp (17) for holding the pipeline suspended from the vessel, wherein the clamp is located in the firing line, and comprises a support device (18) constructed and arranged to allow the clamp to hold the pipeline in a first mode wherein the clamp has a fixed position relative to the positioning device, and in a second mode (52) wherein the clamp is pivotable relative to the positioning device.

Abstract: A lifting system (1) for lifting an item (2) with a vessel (4) comprising a first support (5) and a second support (6), wherein the lifting system comprises an elongate lifting structure (3) comprising a first end (7) and a second end (8), an item connector constructed and arranged to in use connect the lifting structure to the item near or at the first end, a weight (21) connected to a weight connector (10) provided on the lifting structure near or at the second end, a first connector (11) constructed and arranged to connect the lifting structure (31) in use to the first support, a second connector (12) constructed and arranged to connect the lifting structure in use to the second support, wherein the first connector is located at a distance from the item connector in a direction from the first end to the second end.

Abstract: The present invention relates to a semi-submersible vessel comprising at least one lower hull section (22) which defines a first water displacing volume; a support structure (24) connected to the at least one lower hull section (22) and extending upward from the at least one lower hull section, wherein the support structure (24) has a waterplane area which is substantially smaller than the waterplane area of the at least one lower hull section; a deck structure (26) connected to the support structure (24), wherein the deck structure (26) is provided at a distance above the at least one lower hull section (22); a ballast system for controllably varying the draft of the vessel such that at a first draft (30) the at least one lower hull section (22) may be provided at least in part above the water-line and at a second draft (28) the support structure may be provided at least partly below the water-line; wherein the assembly of said at least one lower hull section, said support structure and said deck structure c

Abstract: A J-lay system constructed to be positioned on board a pipeline-laying vessel, comprising a fixed pipeline support (12) and a movable pipeline support (12) configured for supporting a pipeline (10) which is suspended form the pipeline-laying vessel, —the movable pipeline support (12) comprising: —at least a first movable support member (20A) configured for engaging a first collar (16A) on the pipeline (10), —at least a second movable support member (20B) configured for engaging a second collar (16B) on the pipeline (10), —the fixed pipeline support (12) comprising: —at least a first fixed support member (20A) configured for engaging a third collar on the pipeline (10), —at least a second fixed support member (20B) configured for engaging a fourth collar on the pipeline (10), wherein the first (20A) and second fixed support member (20B) configured for engaging a fourth collar on the pipeline (10).

Abstract: A method of performing an under water operation on a structure (10) or in the vicinity of the structure includes providing a device (18) having a movable arm (20) and at least a first support (22) constructed to be connected to the structure, the movable arm (20) directly or indirectly connected at a proximal end (34) to the support, the first movable arm having a first tool (30) connected to a distal end (36) of the first movable arm, at least one actuator (33) configured to controllably move the first tool (30) in a three dimensional working range in order to position the first tool at a target location, attaching the device to the structure via the at least one support, and-moving the tool in three dimensions and performing an operation under water.

Abstract: The invention relates to an axial displacement device (3) to be used in conjunction with a rotary winch (2), said winch comprising a drum (7) being rotatable about an axis of rotation (a-a), said axial displacement device to be arranged stationary with respect to said winch and comprising one or more guiding elements (23), said one or more guiding elements being configured to displace a winding of said line in an axial direction parallel to said axis of rotation with at least the diameter of said line, so that a part of said winding being in contact with said drum runs in a plane substantially perpendicular to the axis of rotation.

Abstract: A stinger (1) for a pipeline laying vessel, the stinger includes at least one track (3) which in use at least partly surrounds a firing line along which the pipeline (5) is laid, and at least one pipeline support (6) for supporting the pipeline, which pipeline support is movable along said track.

Abstract: A pipe element (1) for constructing a double walled pipeline includes an outer pipe element (3) and an inner pipe element (4) located inside the outer pipe element (3), the outer pipe element (3) has a substantially annular form in cross section and includes an inner surface (16). The inner pipe element (4) has a substantially annular form in cross section and includes s an outer surface (15), the diameter of the inner surface is larger than the diameter of the outer surface. The outer pipe element (3) is made from a metallic material, and the inner pipe element (4) is made from a non-metallic material.

Abstract: The present invention relates to a pipeline guide assembly for a pipeline laying vessel, the pipeline guide assembly comprising:—a plurality of segments (20) pivotably interconnected via hinges (38) in an end-to-end relationship, each segment comprising at least one pipeline support (34) constructed to support a pipeline, wherein the pipeline supports provide a firing line (24) along which a pipeline can be launched,—a curvature mechanism (32) comprising at least one actuator (68, 68a, 68b, 68c, 68d), the curvature mechanism constructed for pivoting each segment relative to the next segment such that in use the segments provide a curved firing line, wherein the pipeline supports limit the curvature of the pipeline as it is launched along said curved firing line. The present invention also relates to a vessel comprising the stinger. The present invention also relates to a method of laying a pipeline utilizing the stinger of the invention.

Abstract: A vessel (1) for laying a pipeline (2), comprising a tower (3) which comprises a firing line (4) and is connected to the vessel by a hinge assembly (5) comprising a tower pivot axis (6), wherein: the tower is pivotable relative to the vessel about the tower pivot axis, during pipelaying the tower comprises an upper end and a lower end and the pipeline moves relative to the vessel along the firing line in a laying direction from the upper end towards the lower end, and the tower pivot axis is located at a distance D1 from said upper end as viewed in the laying direction, a system for abandoning and recovering the pipeline, wherein: the system comprises at least one line for lowering and raising a member configured to be connected to the pipeline, and the at least one line is supported by the hinge assembly and/or by the tower at a distance of at least ? D1 from said upper end as viewed in the laying direction.

Abstract: A vessel (1) for laying a pipeline, the vessel comprising a hull structure (3) comprising one or more floaters (4), a tower (5) defining a firing line (6) when positioned in a pipelaying position, the tower (5) being pivotable relative to the hull structure (3) about a tower pivot axis (7), and an A & R means (8) for abandoning and/or recovering the pipeline, wherein the tower (5) is pivotable about said tower pivot axis (7) substantially independent from the A & R means (8) and the A & R means (8) is configured to operate while the tower (5) is pivoted about said tower pivot axis (7).

Abstract: The present invention relates to a sealing device that is configured to form a seal around a pipe by use of an air flow in order to prevent a fluid from passing the sealing device. The sealing device includes an air inlet for the inflow of compressed air and configured to be connected to a source of compressed air; one or more channels connected to the air inlet, the channels extending along a substantially annular trajectory and configured to—in use—extend substantially around the pipe; a plurality of outlet points or an annular outlet groove connected to the one or more channels, the outlet points being configured to blow the compressed air in the region of the pipe wall, in order to create an air flow about the pipe in order to prevent a fluid from passing the sealing device.

Abstract: A vessel for removal and/or installation of at least a part of a sea platform includes a support structure and a top side. The vessel includes a hull and two support arms located at a distance from each other and attached to the hull. In use, the support arms extend beyond the hull in a substantially horizontal direction.

Abstract: A traction device for paying out and retrieving a flexible line including a line mover, wherein the line mover includes at least one movable friction surface, the friction surface in total defines at least two arc sections configured to move the line along with the arc sections, in use the line is wound around the friction surface such that the line has a first contact area being in contact with the first arc section and a second contact area being in contact with the second arc section, and the traction device includes a line controller coupled to the line between the first contact area and the second contact area and configured to control the velocity with which the line in use is fed to the second arc section, and also a method and use of the traction device.

Abstract: A method for constructing a riser assembly (1) for transporting a fluid from a vessel and on a seabed includes providing an elongate frame (4) having a first frame end (5) and a second frame end (6), where the first frame end is connected to the seabed (3) and the second frame end is connected to a buoy (7), providing at least one riser (9) for transporting a fluid, and connecting the at least one riser to the second frame end and/or the buoy.