Platform deck installation and removal method and apparatus

Abstract

An apparatus for loading a topside onto a jacket is provided. The apparatus may include: a projecting structure extending beyond a deck of a marine vessel wherein the projecting structure configured to support the topside and the projecting structure is dimensioned sufficiently long enough to allow the marine vessel to approach a submerged jacket and position the topside above the submerged jacket without having the marine vessel contact the jacket; and a support configured to support the topside above the projecting structure. A method for one of installing and removing a topside from a jacket may be provided. The method may include: positioning sponsons attached to a marine vessel around a jacket; supporting at least part of the weight of the topside on the sponsons; and one of attaching and detaching the topside and jacket.

Description

FIELD OF THE INVENTION[0001]The present invention relates generally to a method and apparatus for loading heavy offshore oiling equipment onto a submerged support such as a jacket. More particularly, the present invention relates to a method and apparatus for loading a topside onto and / or off a jacket.BACKGROUND OF THE INVENTION[0002]As the demand for oil continues to increase, more and more oil fields are being identified as beneath the ocean floor. Traditionally, with offshore oil production platforms, either fixed or floaters, the topsides are installed to the substructures, jackets or hull, by a specially designed heavy lifting vessel such as a crane vessel. However, the use of heavy lifting vessels presents a variety of challenges including the reliability of being able to safely lift heavy structures, the availability of vessels capable of lifting required amounts of weight. Strict environmental requirements can create narrow weather windows in which operations may be done. Hi...

AI Technical Summary

Problems solved by technology

However, the use of heavy lifting vessels presents a variety of challenges including the reliability of being able to safely lift heavy structures, the availability of vessels capable of lifting required amounts of weight.

High operational costs of using lifting vessels have encouraged the oil gas exploration and production industry to look for alternative ways to load heavy structures onto platforms.

Furthermore, float-over techniques can require shorter time and the weather window for performing such operations is wider than what is required in heavy lifting techniques.

However, the use of float-over technology is not without its drawbacks.

However, this is not favored for small platforms since the advantages of cost-efficiency disappear.

However, many older jackets or ones that are traditionally designed may not have legs wide enough to accept the single barge.

As such, they present additional difficulties in using a single barge or vessel with the float-over technique.

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