| 摘要 |
A system for offshore operations includes a column (1) extending above sea level from the seabed, which is connected by a bridge (2) to a semisubmersible offshore oil production platform (3). The connection of the bridge (2) to the platform (3) is achieved by an improved joint arrangement which permits relative rotation about both substantially vertical and horizontal axes to reduce loads transmitted to the column. The column (1) is connected by a universal joint arrangement (4) to a base on the seabed. The joint (4) has radially outwardly distributed joint surfaces which provides an axial passageway through the joint for risers. The joint arrangement includes a first main joint and a second normally unloaded ball joint which takes up the column loaded in the event of failure of the first joint. |
