A system for remediating a blockage in a subsea component including a riser extending from a surface vessel, a flexible jumper having an upper end coupled to the riser and a lower end coupled to a subsea component, and a surface system disposed on the surface vessel and including flexible tubing configured to be inserted and advanced through the tubular string and flexible jumper to the blockage.

A vortex induced vibration suppression system including a buoyancy module dimensioned to at least partially encircle an underlying tubular, the buoyancy module having an exterior surface and a groove formed inwardly from the exterior surface; and a collar dimensioned to at least partially encircle the underlying tubular, the collar having a web, a set of flanges extending from the web, and at least one engaging member dimensioned to engage with the buoyancy module, when the collar is positioned around the underlying tubular.

Pipelines with a control system and forced circulation of fluids through the annulus between an inner barrier and an outer cover of a pipe use a system configured to force circulation of fluids through the annulus. The pipe includes segments (T1, T2, T3, TN) joined together by means of connectors, wherein each segment of the pipe has an injector pipe (I1, I2, I3, IN) for injecting fluid into the annulus at a first end of the segment, and a return pipe (R1, R2, R3, RN) for removing fluid from the annulus at a second end of the segment.

The present invention provides a buoyant system and method for a hydrocarbon offshore floating platform to be coupled and decoupled from a subsea buoyant extension with risers slidably coupled thereto. The buoyant system can allow rigid risers to be coupled and decoupled and alternatively move between a first elevation below the offshore floating platform, such as at the buoyant extension, and a higher second elevation at the offshore floating platform independent of a spool piece, arch support, and flexible joint for the risers. The buoyant system can reduce riser stress by reducing bending required for the riser to form a catenary or other curved shape even as a rigid riser.

A generally cylindrical element adapted for immersion in a fluid medium, the cylindrical element comprising an elongate body having a length and a generally circular cross-section, and a plurality of raised body portions disposed about and extending along the length of the elongate body, the raised body portions being arranged generally parallel to a longitudinal axis of the body and having a height between 2% and 10% of a diameter of the body. The plurality of raised body portions are adapted to reduce vortex-induced vibration and/or drag on the cylindrical element when the cylindrical element is immersed in the fluid medium and there is relative movement between the cylindrical element and the fluid medium.

A drilling marine riser section comprises a main riser pipe with radially extending flanges and multiple auxiliary pipes at least comprising a choke line and a kill line. One or more clamps retain the auxiliary pipes. Further the riser section has buoyancy members. The choke line and the kill line are connected to each of the flanges in a tensile load sharing arrangement, so thatin vertical use orientation of the riser section in a riser stringweight stress is distributed in the main riser pipe and the choke line and the kill line. The buoyancy members form an exterior of the riser section including diametrically opposed and parallel flat bottom and top stacking faces relative to the axis of the main riser pipe, allowing stacking of riser sections in horizontal orientation. The choke line and the kill line are arranged diametrically opposite from one another and between the flat bottom and top stacking faces.

Techniques and systems to reduce deflection of a riser extending from an offshore vessel. A device may include a fairing assembly having a body segment configured to at least partially circumferentially surround a main tube of a riser joint of the riser, and a tail segment. The tail segment is configured to retract into a collapsed position and extend into an expanded position along an expansion direction. An expanded width of the fairing assembly in the expanded position is between 20 to 200 percent greater than a collapsed width of the fairing assembly. In some embodiments, the collapsed width of the fairing assembly is less than 1.5 times a length across the main tube, and an expanded width of the fairing assembly is greater than 1.5 times the length of the main tube.

Techniques and systems to reduce deflection of a riser extending from an offshore vessel. A device may include a fairing assembly having a body segment configured to at least partially circumferentially surround a main tube of a riser joint of the riser, and a tail segment. The tail segment is configured to retract into a collapsed position and extend into an expanded position along an expansion direction. An expanded width of the fairing assembly in the expanded position is between 20 to 200 percent greater than a collapsed width of the fairing assembly. In some embodiments, the collapsed width of the fairing assembly is less than 1.5 times a length across the main tube, and an expanded width of the fairing assembly is greater than 1.5 times the length of the main tube.

Buoyancy modules (200) are made from a foam composition that includes a combination of a thermally fusable powder and glass microspheres heated in a manner that provides a hardened syntactic foam having both low density and a high degree of compressive strength. An outer barrier (220) may enclose the buoyancy module.

A clamping arrangement 10 of a buoyancy clamp assembly. The arrangement 10 includes three identical arcuate members 12 engageable together to define a ring. Each of the arcuate members 12 has three discrete resilient members 14 engageable on for instance a pipe 68. Engagement members 42 are provided extendable between adjacent pair of arcuate members 12 to prevent relative twisting of adjacent arcuate members 12.