A system and method for laying an underwater pipeline is provided. The present invention includes a plurality of pipe support rings connected together by tension cables. The tension cables are secured to a S or J laying ship by a winch. The plurality of pipe support rings form a pipe channel sized to guide the underwater pipeline. The present invention further includes a sea water pipe having a distal portion and a proximal end. The proximal end is fluidly connected with a pump on board the ship. The distal end includes a plurality of nozzles. The sea water pipe is disposed underneath the plurality of pipe support rings. The underwater pipeline is fed through the plurality of pipe support rings while the nozzles form a trench on a sea bed.

A method of clamping elongate elements in a parallel piggybacked arrangement during subsea laying of the elements is disclosed. The method includes opposed reciprocating jaws which force together clamp segments around the elongate elements to assemble a piggybacking clamp. The piggybacking clamp applies clamping forces to the elongate elements.

A method for installing an accessory onto a pipeline to be laid on the seabed, includes launching the pipeline from a first position of a tower in which the tower is at an angle α with respect to the vertical; stopping the launch of the pipeline, and hanging off the launched pipeline in a hang off module; positioning an accessory in a tower firing line; attaching the accessory to the launched pipeline in the hang off module and to at least one A&R cable; suspending the accessory and the launched pipeline from an A&R system; disengaging the hang off module from the launched pipeline; pivoting the pipeline launch tower to an accessory launch position in which the tower is at an angle γ that differs substantially from angle α, such that a pipeline launch trajectory is created which is large enough to launch the accessory and the launched pipeline with the A&R system.

A portable subsea storage tank for the storage of gas products under pressure or oil products consisting of pipeline sections in an array which can be coated in specialist coatings and recovered for inspection and re-use. A method of self-installing the subsea storage tank is also described.

A portable subsea storage tank for the storage of gas products under pressure or oil products consisting of pipeline sections in an array which can be coated in specialist coatings and recovered for inspection and re-use. A method of self-installing the subsea storage tank is also described.

A tower for a pipe laying system comprises a frame with a leg to support the frame, and a winch support integrally formed with the leg. The winch support is able to receive and support a winch and/or winch components. The winch support can be formed in a lower portion of the tower leg.

System for use in building and deployment of an elongate element (202) in a J-lay operation. The system includes an upright structure (206); a winching element (204) retractable along an axis within the upright structure (206); a coupling element (210) connected to the winching element (204), for coupling the winching element (204) to an elongate element (202); and a catcher element (212) configured to retain the coupling element (210) in alignment with a predetermined axis within the upright structure (206) during retraction or extension of the winching element (204).

The present invention relates to a marine pipelaying friction clamp device for frictionally retaining an offshore pipeline having a longitudinal axis, comprising multiple clamping units (20). Each clamping unit comprises a friction pad (21) and an associated force actuator (22), and further comprises a base (25) fixed to the actuator, wherein the friction pad is rotatably connected to the base via a single axis (H1, H2) hinge mechanism defining a single hinge axis parallel to the longitudinal axis. The single axis hinge mechanism comprises first and second complementary semi-cylindrical hinge surfaces, allowing a rotation of the friction pad about the single hinge axis over 2-20 relative to the base. The friction pad is also axially connected to the base via complementary axial load surfaces (31, 33) on the base (25) and on the friction pad (21).

A method and apparatus for direct tie-in of pipelines are disclosed. An apparatus is attached to a portion of a pipeline, the apparatus including a tensioning member and a buoyancy element attached to the tensioning member such that, when submerged, the pipeline is deflected as a result of a buoyancy force tensioning the tensioning member, and on releasing the buoyancy element, direct tie-in of the pipeline is performed.

A tower for a pipe laying system comprises a frame with a leg to support the frame, and a winch support integrally formed with the leg. The winch support is able to receive and support a winch and/or winch components. The winch support can be formed in a lower portion of the tower leg.