초록 ▼

A deep draft semi-submersible offshore structure suitable for conducting mineral exploration and production operations in deep waters of the oceans. The structure uses three or more caissons or columns equidistantly spaced from adjacent columns. The weight distribution and provision of liquid or sol

A deep draft semi-submersible offshore structure suitable for conducting mineral exploration and production operations in deep waters of the oceans. The structure uses three or more caissons or columns equidistantly spaced from adjacent columns. The weight distribution and provision of liquid or solid permanent balance in the lower ends of each column make the structure stable without reliance upon water line displacement or tendons, as compared to conventional vessels. The center of gravity of the structure is maintained below its center of buoyancy, thus imparting an inherent absolute stability to the structure. The columns are retained in spaced relationship to each other by a plurality of horizontal braces or a combination of horizontal braces and diagonal braces. The major part of the structure is positioned below the water surface at sufficient depth to minimize the reaction to surface changes, thereby greatly reducing heave and angular response to surface wave action.

대표청구항 ▼

[ In the claims:] [1.] A deep draft semi-submersible floating structure, comprising:a plurality of independent vertical buoyant columns having individual ballast means for accommodating eccentricities of a deck supported by upper portions of said columns and/or operational loads so as to prevent mut

[ In the claims:] [1.] A deep draft semi-submersible floating structure, comprising:a plurality of independent vertical buoyant columns having individual ballast means for accommodating eccentricities of a deck supported by upper portions of said columns and/or operational loads so as to prevent mutual load transfer between said columns, each of said columns comprising a cylindrical outer shell reinforced with corrugated stiffening panels secured to an interior surface of said outer shell and extending through substantially entire length of each of said columns and a ring frame mounted in a concentric relationship to said outer shell a distance away from said stiffening panels;a plurality of horizontal bracing members positioned between said columns at a plurality of vertical locations along said columns for retaining said columns in a spaced-apart relationship to each other; andwherein a center of gravity of said structure is maintained below a center of buoyancy.