Offshore floating structure for drilling, production, storage and unloading

摘要

A floating structure (10) having a central vertical axis, said structure being arranged and designed for drilling, production, storage and discharge of oil, comprising: a hull (12) having an upper cylindrical part (12b), including said hull an upper frustoconical part (12c) connected directly to the lower part of said upper cylindrical part (12b) and having walls inclined downwards and inwards, said inclined walls inclined downwards and inwards at an angle of between 10 and 15 degrees with respect to said central vertical axis, said angle being large enough to provide damping to the downward thrust of said structure in response to oceanic oscillations, but small enough to provide a large storage volume of said part upper conical trunk, said helmet including a lower conical trunk part (12d) arranged below of said upper conical portion (12c) and having walls inclined downwards and outwards, said walls inclined outwardly at an angle greater than or equal to 55 degrees but less than 65 degrees with respect to said central vertical axis, in order to provide a great inertia to said structure for the thrust and pitch movements, thus providing natural periods of thrust, pitching and balancing on the expected wave energy of the ocean, but small enough to avoid sudden changes in stability during ballasting during installation, and said hull including a lower cylindrical part (12e) connected directly to the lower part of said lower conical trunk part (12d), wherein the lower part of said lower cylindrical part (12e) defines a keel (12f) of said hull (12), and the upper part of said upper cylindrical part (12b) defines a main cover to (12a) of said structure (10), said structure being characterized by a low center of gravity (CG) that provides inherent stability with said low center of gravity (CG) that improves a metacentric height of said structure which results in a large straightening movement, said structure having a ballast in one or more ring-shaped compartments (80) that are located in the outermost parts of said lower cylindrical part (12e), thus further increasing said straightening movements.