Device for positioning an off-shore platform on its support structure
AssigneeAteliers et Chantiers de Bretagne-ABC
InventorsJean-Louis Ninet, Robert Vaillant
Life of this patent
Estimating the term…
Abstract
A device for positioning an off-shore platform (1) on a previously-installed support structure. Said platform has support piles (6) designed to rest on legs (4) of the support structure. The device includes means for bringing said support piles towards said legs which are provided with centering cones (5). Each pile is constituted by a tube containing a rod (13) associated with a damping unit (8). The lower portion of the rod (13) has a centering pin (16) and extends below the lower end of the pile in the damping unit rest position.
Claims9
A device for positioning an off-shore platform on a previously-installed support structure, said support structure including vertically upstanding legs, said platform having support piles designed to axially align with and to rest on the legs of the support structure, said platform further comprising means for moving said piles vertically to move said piles downwardly towards said legs and for locking said piles at an axially displaced position with respect to said platform, said legs including upwardly open centering cones, each pile being constituted by a hollow tube, a rod slidably positioned coaxially within said tube, said rod terminating at its lower end in a centering pin for reception within said centering cone of said leg, a resilient, compressible shock-absorbing component fixed to said rod and operatively interposed between said rod and said hollow tube, and means for effecting controlled sliding of said rod bearing said reslient, compressible shock-absorbing component within said hollow tube to effect precompression of said shock-absorbing component during transport of said platform to the situs of said previously installed support structure and for facilitating final positioning of said pile against said leg without impact and for taking up the load of the platform as transmitted to the leg to facilitate welding of said pile to said leg at the interface between the pile hollow tube and said leg about said centering cone.
A process for positioning of an off-shore platform on a previously installed support structure, said support structure including vertically raised legs, said platform having support piles corresponding to said legs and intended to rest on said legs of said support structure, and means for mounting said piles on said platform for vertical movement to said platform and for selective locking of said piles in position on said platform, and wherein each pile is constituted by a tube bearing a slidable rod abutting a shock-absorbing component and having means for controlled sliding of the rod in said pile, and wherein the lower part of the rod contains a centering pin extending beneath the lower end of the pile for reception within a support cone borne by said leg, said process comprising, during transport of said platform:
- partially compressing said shock-absorbing component by the weight of the platform and by operation of said means for effecting controlled sliding of said rod within said pile,
- partially releasing the precompression of said shock-absorbing component when the piles are aligned with said legs,
- driving said piles vertically downwardly relative to said platform to engage the centering pin of said hollow rod with the support cone of said leg, while completely compressing said shock-absorbing component,
- effecting controlled sliding of said rod to partially release the compressed shock-absorbing component and to remove the clearance between the pile and said leg,
- welding said pile to said leg,
- cutting said pile subsequent to platform installing, and
- removing and hoisting said hollow rod and said shock-absorbing component from the interior of said pile for subsequent re-use without affecting the positioned off-shore platform relative to the support structure.
Dependencies are inferred from the claim text.