Abstract: A floating platform with motion characteristics for offshore deepwater developments with vertical axial symmetry and decoupling of hydrodynamic design features. A motion-damping skirt (120) is provided around the base of the hull (1), which is configured to provide ease of installation for various umbilicals and risers. A retractable center assembly (300) is used in a lowered position to adjust the center of gravity and metacentric height, reducing wind loads and moments on the structure, providing lateral areas for damping and volume for added mass for roll resistance. The center assembly (300) is used to tune system response in conjunction with the hull damping skirt (120) and fins (121). The center assembly (300) also includes separators (350) below the floating platform deck which serve to add stability to the floating structure by shifting the center of gravity downward, the separators (350) capable of being raised and lowered vertical separators alone or as a unit.

Abstract: A mechanical joint assembly for a steel catenary riser (SCR) is disclosed. The lower section of the mechanical joint assembly is comprised of steel or alternate high strength components, rather than elastomers to absorb the high loads and increase life of the unit. The lower mechanical joint assembly provides for reduction of bending moments and resulting fatigue stresses at the SCR top by removing resistance to movement in all angular directions, providing increased lateral and in-plane angles to provide increased construction tolerances for the pipeline approach corridor. Pipeline approach angle increase is accommodated by providing dual orthogonal trunnions in addition to an axial swivel. The upper mechanical joint assembly, acting without riser tension loads, allows for the use of either flexible high-pressure pipe or swivel arrangements to accommodate angular flexure before the rigid deck piping.

Abstract: A support structure is disclosed for use in drilling and production operations having one end positioned above a body of water and another end below the body of water on a bed. The support structure includes a base and a jacket structure having at least three jacket legs and support members for supporting a structure, such as a deck. The base has at least four cylindrical base legs engageably positioned in a generally rectangular pattern on the bed and a base frame connected to the cylindrical base legs. The cylindrical base legs start and terminate below the body of water. The jacket has a first jacket leg, a second jacket leg, a third jacket leg. The first, second, and third jacket legs start below the body of water and terminate above the body of water and are positioned with the support members for supporting a structure above the body of water. The first jacket leg is attached to one of the cylindrical base legs and the second jacket leg is attached to another of the cylindrical base legs.

Abstract: A support structure for use with at least two wells, and a method for providing and supporting at least two wells in the ground beneath a body of water, includes a caisson, a plurality of conductors, and a guide frame, which support at least two wells without the use of any piles or brace members, the at least two wells being supported solely by the conductors, the caisson, and the guide frame.