Importance

Loading Importance Indicators...

Abstract

An offshore hydrocarbon production system is provided, which is of relatively low cost. The system includes a vessel (12) having a platform (24) that allows the vessel to rotate about a vertical axis with respect to the platform, and a column (14) having an upper end pivotally connected to the platform about horizontal axes (32, 34) and a lower end anchored solely by a group of loose chains (38) that permit the lower column end to tilt and move in every direction. The lower end of the column is weighted by a counterweight and by the chains, so the column acts like a pendulum that tends to return to the vertical when tilted, to urge a drifting vessel back towards its quiescent position. The bottom of the column also moves laterally during such vessel drifting, increasing tension in one chain (38a) and reducing tension in an opposite chain (38b) to also urge the vessel back towards its quiescent position. The column can be sunk with the vessel sailing away, and its reconnection to the vessel is facilitated by the provision of a two-axes joint at the bottom of the platform.

Loading the Abstract Image...

First Claim