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FLOAT-OVERS: WHATS PRESENT AND

WHATS NEXT

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Agenda

Float-overs: An introduction

Present status of Float-over technology

Whats next for Dockwise?

Conclusions

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Recent changes

Jan 2007: Sold by Heerema to 3i

April 2007: Merged with Sealift Ltd. (6 new vessels)

July 2007: Acquisition of OKI/ODL

Oct 2007: IPO on Oslo Stock Exchange

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The Dockwise business

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The ODL Business

OffshoreFloatoverInstallation

DeepwaterFixedStructure

FloatingSystemDesign

Deepwater jacket structure

Compliant piled tower

Conventional jacket and deck

Conventional single barge floatover

Twin barge floatover

Floatover on jacket and floater

Global performance and sizing

Stability, motion, mooring and riser

Global and local structure, 2nd steel

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The ODL Resources

Houston Head Office

13 full time employees Highly educated and experienced

employees include 6 professionalengineers, 6 Ph.D.s

China Office, Shenzhen

19 full time employees 9 master degreed engineers

ODL Expertise

Specializes in analysis and design of offshore installation, offshore structures(fixed and floating), mooring system and riser systems

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Float over principleFixed substructure

East Area GN Deckon HTV Black Marlin

Operator:ExxonMobil

Weight: ~18000 mT

Location: Offshore

Nigeria

I

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Float over principlesemi submersible

Statoil Kristin FPU

Contractor:

AkerKvaerner

Weight: ~19000 mT

Location: inshore

Norway

I

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Float over principleSpar

Murphy Kikeh Spar

Contractor: Technip

Weight: ~4000 mT

Location: Offshore

Malaysia

I

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SafeFast

Cost effective

Efficient

WHY?

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Float-over Sequenceload-outCritical Factors in a Loadout Operation:

Vessel pumping capacity;

Vessel strength/skid beam design;

Pulling jack capacity and reliability;

Integrated deck weight and skidding friction;

Tidal range;

Quayside dimensions.

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Float-over Sequencesea transportationCritical factors during sea transportation:

Vessel stability vs. deck weight/CG height;

Global strength of vessel;

Local strength of vessel;

Sea fastening arrangement vs. motion inducedforces.

12.000 tons@

18.00 m

60.000 tons@

37.00 m

63.00 m 42.00 m

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Float-over SequencedockingCritical factors during docking operation:

Heading control of the vessel; Transverse control of the vessel w/ away

fenders and cross lines;

Longitudinal control of the vessel with mooringlines and cross lines;

Control impact loads on jacket w/sway fenders; Maintain vertical clearances during entry and

withdrawal operations.

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Float-over Sequencemating: non-swell environmentsCritical factors during mating operation

Limit horizontal excursion circle prior to lowering operation through fenders & cross lines:

Minimize vertical impact loads between jacket & deck legs through installed LMUs; Minimize vertical impact loads between deck legs and vessel deck through DSUs;

Achieve load transfer from vessel to jacket legs through vessel ballasting;

Continue vessel ballasting until sufficient vertical clearances for withdrawal operation.

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Float-over Sequencemating: swell environmentsCritical factors during mating operation

Limit stabbing cone horizontal excursion within designed circle by an anti-surge system;

Minimize vertical impact loads between jacket & deck legs through hydraulic cylinders and LMUs; Minimize vertical impact loads between deck legs and vessel deck through quick separation system(hydraulic cylinders) and DSUs;

Achieve load transfer from vessel to jacket legs through vessel ballasting and cylinderextension/retraction;

Combined vessel ballasting and cylinder retraction for vertical clearances prior to exit operation.

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0

5000

10000

15000

20000

25000

30000

35000

40000

1990 1992 1994 1996 1998 2000 2002 2004 2006 2008

Year

Deckweight

[st]

Whats presentintegrated deck weights and number of installed decks

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Whats presentpassive float-over methods Load transfer only by vessel ballasting;

Moderate to mild wave climate w/o swells;

Sufficient draft fluctuation of the vessel to suit requirement; Utilization of LMUs and DSUs to reduce impact loads;

Capacity >21000 tons.

Full load onDSUs

0% Load

Partial load on

DSUs

Partial load onLMUs

0% Load

Full load w/Steel-to-Steel

contacts

BallastBallast Ballast

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Whats presentactive float-over methods Active lowering system w/ cylinders integrated with deck supports;

Applications in swell environments during installation seasons (5 of 12months in West Africa environments);

Require an anti-surge system to reduce excursion circle;

Draft fluctuation insufficient to create gaps for entrance/exit clearances;

Quick separation system is required to obtain vertical exit clearances;

Capacity 18.000 tons or less so far.

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Whats present?pontoon barge method

No slot required for fixed jackets;

Suitable for SPAR buoys;

Require a transfer operation prior toinstallation;

Not suitable for long distance sea voyage

under pontoon barge configuration;

One successful installation for fixed jacketby ODL for Corocoro WHP project;

One successful installation for Kikeh Sparproject by Technip.

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Whats next for Dockwise?Strengthen R&D Efforts and Improve Market Position

Combined efforts through Dockwise, ODL and OKI;

Introduce Friction Fender concept for harsh swell conditionapplications w/o hydraulic cylinders;

Improve Pontoon Barge Method w/o a transfer operation;

Introduce Outrigger method to improve vessel stability for highCG and heavy decks.

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Whats next?friction fender concept for WA applications Objectives:

Utilize friction to reduce vessel heave motions;Eliminate hydraulic cylinders to improve system reliability;

Suitable for floating and fixed platform topsides installations;

Increase installation season in WA from current 5 months to 12 months long.

Concept confirmed in studies and a model test is planned in 2008;

Software development is required for the system calculations.

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Whats next?improve pontoon barge method Loadout directly onto two pontoon barges at fabrication yard;

Purposely built pontoon barges; Suitable for transportation under harsh environments;

Suitable for both fixed and floating platforms;

Joint study with CNOOC is underway.

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Whats next?outrigger concept For high CG heavy decks, stability, not displacement, is the big challenge;

Increase stability by adding removable sponsons far away from vessel CL; Whole system, sponsons plus truss, is independently maneuvered and transported;

Increase transport speed by adding self-propulsion systems to the sponsons;

Suitable for transverse loadout;

Internal development is underway.

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Conclusions

Float-over is a mature installation method;

Float-over is a competitive alternative for:

Integrated decks beyond crane vessel capacity;

Integrated decks to be installed in remote areas;

Less environmentally sensitive than lifting option.

Improvements to be expected in the fields of:

Workability and system reliability under swell environments;

Installation capacity for heavy and high CG topsides;

Alternative float-over system such as pontoon barge method.

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Jan Wolter OosterhuisDockwise USA LLC

janwolter@dockwiseusa.com

James Lee

Ocean Dynamics, LLCjames.lee@oceandyn.com