An offloading system for conveying hydrocarbons from a buoyancy-supported subsea riser to a surface tanker vessel comprises a flexible hose that hangs from the riser structure in a U-shape having first and second limbs. An upper end of the first limb communicates with the riser and an upper end of the second limb terminates in a pulling head for connecting the hose to the tanker. A clump weight acts on a lowermost bend of the hose between the limbs to maintain tension in the limbs. A subsurface holder fixed to the riser structure is arranged to hold the pulling head against the tension in the second limb of the hose when the system is in a standby state. The holder is offset laterally from a central longitudinal axis of the riser structure and a counterweight is positioned to a side of that axis opposed to the holder.

A subsea riser is installed by lowering at least one riser conduit to the seabed when piggybacked to an elongate support that comprises at least one flowline. The elongate support may be a pipeline bundle, which may be attached to one or more towheads in a towable bundle unit. The riser conduit may be in fluid communication with the flowline. At the seabed, a free end portion of the riser conduit is detached from the elongate support by releasing subsea-releasable fastenings. Then, with the elongate support and a root end of the riser remaining at the seabed, the detached free end portion of the riser conduit is lifted away from the elongate support to a riser support, such as a platform, an FPSO (floating production, storage and offloading vessel), or a buoy.

A method of installing a wave-configuration subsea riser of unbonded flexible pipe comprises lowering the riser progressively into the sea from an installation vessel while suspending an elongate clump weight in a catenary shape that comprises first and 5 second limbs extending upwardly from a conjoining bottom portion. An upper end of the first limb, at a distal end of the clump weight, is attached to the riser and an upper end of the second limb, at a proximal end of the clump weight, is suspended from a winch or crane of the vessel. While lowering the riser from the vessel, the weight load applied to the riser by the clump weight is controlled by adjusting the relative lengths of the first 0 and second limbs of the clump weight.

In order to achieve the objects described above, the present invention provides an adapter tool for coupling a ben stiffener with interface for bell mouths of models with connection type BSN900E in a diverless bell mouth (BSDL), consisting of a adapter split ring (1), guide pin holes (C), fastener eyes (D), and through holes (E). The adapter tool is capable of keeping interchangeability and flexibility between projects or project phases, even if different bellmouth models are used. The interconnection method between the helmet (9) and the adapter split ring (1) can be done by direct attachment by bolt, or by attachment by ring/rod support. Both interconnections can be made on board a flexible line launching vessel, in the case of reusing lines from other projects, or at the factory, in the case of sharing new flexible lines.

An offshore production system includes a surface vessel, a tubular tendon extending between the surface vessel and a lower connection system disposed at a seabed, the riser coupled to the surface vessel with an upper connection system, and an electrical cable extending through a central passage of the tubular tendon, wherein the upper connection system comprises a connector that physically supports the electrical cable.

A subsea clamp connector for connecting the ends of two tubular members to each other, the clamp connector including first and second clamping elements, which are pivotable into a closed position in clamping engagement with the ends of the tubular members; and a replaceable locking unit for locking the clamping elements in the closed position. The locking unit includes an operating shaft, a first retaining member mounted to the operating shaft and configured for engagement with a shoulder on a holding member fixed to the first clamping element, and a second retaining member mounted to the operating shaft and configured for engagement with a shoulder on a holding member fixed to the second clamping element. The locking unit is detachably mountable to the clamping elements by insertion of the operating shaft sideways into slots provided in the holding members.

This invention relates to oil and gas exploration and comprises a direct connection system referred to as a Lower Riser Termination Assembly (LRTA), between risers made of composite material and horizontal lines installed on the seabed (flowlines). The system is applicable to a hybrid riser and its construction method allows cost reduction and system assembly/installation time optimization. The LRTA connection system is applicable to both rigid and flexible flowlines without need for any intermediate connection section/equipment between these and the risers. The construction of the system allows free vertical expansion of the risers along the entire structure. In addition, in the construction method developed for this system, the required area is significantly reduced.

A tensioning system includes a combined rope gripper and tension cylinder. A rope passes through the combined rope gripper and tension cylinder. Once the length and/or tension of the rope has been adjusted, a reel lock handle can be actuated to prevent further rotation of the reel. The combined rope gripper and tension cylinder can be actuated to hold the rope. The combined rope gripper and tension cylinder can also be actuated to reduce or prevent the release of tension in the rope.

A method of lowering a discrete load (32) from a pipelay yessel comprises: holding a rigid rod (30) on an upright launch axis where the rod extends through a hold-back system (26); coupling a lower end of the rod to the load; connecting a wire (24) to the load either directly or indirectly via the rod; operating the hold-back system to advance the rod downwardly, hence submerging the load, while the weight of the load is suspended from the holdback system via the rod; when the load is underwater and beneath the splash zone, transferring the weight of the load directly or indirectly from the holdback system to the wire; and continuing to lower the load in the water, suspended directly or indirectly from the wire. The method may be reversed to recover a load from a subsea location, such as when lifting a wellhead or blowout preventer from the seabed.

The present invention provides a system for coupling between a bend stiffener (1) and a bell month (2) comprising a plurality of locking mechanisms (3), wherein each locking mechanism (3) is secured externally to the bell mouth (2) and comprises a movable lug (30) positioned such as to slope downwards, in which the lug (30) accesses the interior of the bell mouth (2) and is actuated by an elastic element (34) designed to exert pressure on the lug (30) in the direction of the interior of the bell mouth (2).