The Diagram shows the sequences of Float Over, Engage and Install. It also shows the way that misalignments are corrected in the mating.

Obviously the main method of completing the operation concerns controlled ballasting. In some circumstances if the support is not a jacket

then the Floater ballasting may be used with the twin barge arrangemt in a static state of floatation.

The Diagram shows how other activities must be completed before the Topside Module is lifted on. This Diagram shows a Spar a common

platform support in the GOM. Once the Spar is installed ie moored in position then the lift on or Float Over is completed the same as if it were

a Jacket.

More detail Facts are given in Clair 5d_5 Drilling as this dominates the design."Offshore Modules

General" concerns more the style of Platform, which is installed by Float Over or Lifting. For

these sort of Installations, the Module as such is the complete Topsides as one piece. Here we

see the Pick Points for Lifting and Loading onto the Jackets. These Lifts are undertaken by Semi

Subs which have Ring Skewing Cranes on each of their stern quarters. The first phase of such

lifts was in fact using Shear Leg Cranes as singles or in combination with lifts up to 6,000 te.

The next phase saw the advent of the Twin Slewing Cranes and figures of 10 - 12,000 te lifts.

Current lifts for Clair Ridge and other installations see the Twin Crane capability raised to 20,000

te as described in Diagram.

These figures are now surpassed by the "Adventurer" which is not a Crane but a twin

hull (ex tankers) in Cateraman Format with Finger Beams which slot in under the platform. All of

these devices can be used to lift or lower using ballasting. The use includes removal which has

gained some importance and such devices are now being used in the decomissioning of

Platforms

This Diagram shows the structure of the Craft for the Twin

Slewing Crane arrangement to move in Complete Topside

Modules, as Clair. Alternativly the crane can be used to stack the

modules as Boxes. The Jacket top is toped by an MSF, Module

Support Frame and the boxes stacked on accordingly.

In 4a General we looked at

the shapes a module may

have to conform with.

In 4a_1, Clair is taken as

the example of a one

piece lift as total Topsides,

an ultra large module.

Clair V's Clair Ridge. Clair was a one off to meet the restraints

of the Clair Project. Low cost to commence field development

allowed the Project to go ahead. Clair Ridge demanded more

Processing capability and similar jacket designs and Topside

apprach were followed but Clair Ridge demanded 2

Platforms/Jackets. Both Projects keep accomodation one end

seperated by Power Generation and away from the Process

Items. The success of Clair paved the way for Clair Ridge, a far

more Field success than Clair alone.