| 摘要 |
In order to simplify the construction and to reduce the resistance to flow, and to provide a high amount of inertia in relation to all essential axes, an offshore vessel comprises two parallel under-water bodies, four columns mounted symmetrically thereupon, and a multi-deck box-like structure interconnecting the upper ends of the columns. This structure will increase the strength of the vessel so only one horizontal, transverse stay is required between each pair of columns. Below each column there is a 360 DEG -turnable shrouded propeller, which together can hold the vessel stationary, with a vertical line of symmetry in a desired position, for instance above a borehole. The box structure is outwardly completely closed at the bottom and sideplating, and will, in case of need, retain the vessel floating. |
