Jackets are lifted over the stern of Pieter Schelte, for which the vessel is repositioned. After cuts have been made in the legs of the jacket at seabed level or above the pile clusters, as required, the tilting lift beams lift the jacket at the top of the main legs, preferably using quick-connect lifting tools. The jacket is rotated onto the vessel deck by the tilting lift beams, after which it is skidded further inboard.
The single-piece jacket lift method eliminates the need for cutting work at intermediate jacket elevations, and dangerous hooking operations under water.
Strength analyses for typical jacket types have shown that their integrity is guaranteed during lifting, rotation, skidding, transportation and off-loading by Pieter Schelte with no, or a minimum of, local reinforcements.
The removal of a jacket can be performed directly upon completion of the topsides removal, without first requiring the vessel to off-load the topsides.
Besides jackets, the tilting lift beams can lift items such as bridges, tripods, modules or even small topsides, and place them on the vessel deck or a cargo barge.
