deepTechnology news from Subsea 7 - May 2012

seabed-to-surface

World-class welding technologies

Whats inside...

02 Pipeline welding enhancements

04 New riser technologies

05 Precision performance on Pazflor

06 Groundbreaking geotechnics

07 Cutting-edge simulation

08 Mechanically lined pipe extends reach Subsea hydrocarbon sampling skid

09 Swaged end connection for reel-lay pipe-in-pipe

10 Fleet development update

12 AIV commercialised New multipass and backfill ploughs

In-depth technology newsMore than ever before, Subsea 7 continues to commit to the development and commercialisation of new technology, vessels and equipment that deliver technical and cost-effective solutions to our clients in their increasingly challenging environments and operational scenarios.

Many of our most effective technologies are developed in active collaboration with key suppliers from our supply chain. Our development partners play an important role in the emergence of effective new ideas and solutions for our clients, and they cover a unique range of technologies which reflect our global expertise and capability.

We are proud to have received recent industry recognition of one of our pipeline technologies from the Pipeline Industries Guild. One of the industrys foremost bodies, the Guild presented Subsea 7 with the prestigious Subsea Pipeline Technology Award at their annual dinner in London in March for our development work on the installation of mechanically lined pipe using the reellay method, (see page 8 for details of current development work).

In this latest issue of deep7, you can read about our latest applied technology advances in disciplines ranging from pipeline welding to geotechnics, and from advanced vessel design to the installation of ground-breaking subsea infrastructure.

DEEP7 May 2012

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To find out more about any of the technologies featured in this issue contact John Mair, Technology Development Director at john.mair@subsea7.com or email communications@subsea7.com

Welding enhancements in the pipeline

Subsea 7 is developing and implementing leading-edge pipeline welding technologies to satisfy evolving market demand - both in terms of technical specifications and volume - and to meet increasingly stringent pipeline fabrication codes and operator specifications.

Underpinning this technology development are three important strategic investments by the company:

enteringintoatechnicalpartnershipwithCRC-EvansPipelineInternational(CRC),oneoftheworldsleadingdesignersandmanufacturers of automatic welding systems for pipeline construction

committingtoanextensiveweldingR&Dprogrammetomeetfutureindustry demands

theopeningin2013ofanewGlobalWeldingDevelopmentCentreinGlasgow,managedbySubsea7sPipelineProductionGroup(PPG).

Pipeline performance is currently being challenged on a number of fronts not only by high demands on the performance of pipeline weldingprocessesandtheassuranceoftheintegrityofgirthwelds,butalsobytheincreasingusageofhigherstrengthsteels,clad/linedandsolidcorrosion-resistantalloy(CRA)pipe.

Subsea 7 is implementing a welding methodology which meets the following criteria:

Adoptionofacommonapproachtoweldingprocessesandequipment across all fabrication sites

Useofweldingprocesseswhichallowtheheatinputtobecontrolled precisely to optimise weld mechanical and corrosion properties whilst ensuring weld soundness

Useofmechanisedweldingwheneverpracticalinordertominimisewelderintervention.

Subsea7sreeledpipelineproductionfacilityatVigrainNorway,accommodatesthelatestmechanisedweldingtechnology,and

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demonstrates how careful assessment of project requirements and production factors can deliver cost-effective welding solutions.ThenewtechnologyisabouttobedeployedinBrazil,andwillthereafterberolledouttoSubsea7sotherfabricationsitesworldwide.

Inthecaseoflarger-diametercarbonsteelpipelines,theuseofthemechanisedPulsedGasMetalArcWelding(PGMAW)process is now established as the welding method of choice forbothriserandflowlineapplications.Theprocessutiliseslow-heat input which results in excellent mechanical properties inthegirthwelds.

Theprocesscanbedeployedusingeithersingletorch,orinthecaseoflargerdiameterpipe,dualtorchweldinginordertoimproveproductivity.Thissystemishighlymechanisedsothat the role of the welding operator is simply to supervise the processwithminimalinterventionrequired.

Since the current welding system was introduced to Vigra in early2011,about400kmofcarbonsteelpipelinehavebeenfabricated,withproductivityandqualityexceedingtargets.Theoverallweldrepairrate,whichisakeyqualityindicator,islessthan0.5%.

Subsea 7 has further developed the PGMAW process for use inthefabricationofmetallurgicallycladpipe.

Welding of clad pipe requires the use of dissimilar welding filler material,i.e.Alloy625.Subsea7hascarriedoutextensivewelding trials to optimise pulsed welding parameters and shieldinggascomposition. The qualified PGMAW solution makes use of the Controlled MetalTransfer(CMT)processforrootwelding,anadvancedPGMAW technique which allows the weld root to be deposited veryprecisely,givinggoodcontroloftherootbeadqualityandprofile.Thesefeaturesareessentialtomaintainthecorrosion

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performanceofthecladpipeline.Duringproduction,aninternal camera and laser profiling device is utilised to perform anassessmentofthequalityoftherootbead.

The developed welding solution will be implemented in productionthisyearforanumberofpipelineprojects,whichwill involve over 70km of metallurgically clad and mechanically linedpiperisers.

Forsmallerdiameterpipes(4-inchesandbelow)amechanisedwelding system has been developed by Subsea 7 and implementedatVigra.Akeybenefitofthissystemistoprovide a more precise control of the heat input in order to maintaintheoptimummechanicalandcorrosionperformance.

Thissolution,initiallydeployedona2-inchduplexstainlesssteelserviceline,wasbasedontheuseoftheorbitalGasTungstenArcWelding(GTAW)processusingthePolysoudeweldingsystem.Productionweldinghasbeeninprogresssince November 2011 with weld quality and productivity meetingexpectations,andhasconfirmedthatthistechnologycanbesuccessfullydeployedonaglobalbasis.

The 2-inch duplex line was also a Vigra first for the use of an automatic arc monitoring system on the firing line to capture andrecordtheessentialweldingparameters.

Operationswillbeginin2013atSubsea7snewGlobalWeldingDevelopmentCentreinGlasgow,whichwillincorporate 18 welding bays including facilities for J-lay and S-laypipelinewelding,andwillactasacentraltechnicalauthority for the development and qualification of all welding procedures for all Subsea 7 pipeline fabrication bases around theworld.

This major initiative by Subsea 7 will give clients the assurance of quality and delivery of pipeline welding performance at a competitivecost.

For further information contact eric.law@subsea7.com

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DEEP7 May 2012

New riser technologies under constructionMany years of applied research and construction experience have given Subsea 7 the significant advantage of being a SURF contractor capable of providing all types of riser systems for deepwater and ultra-deepwater installation, depending on the field architecture and client needs. This in-house capability includes design, procurement, construction, installation and maintenance.

Risersystemsinstalledonaworldwidebasis by Subsea 7 fall into two categories - those coupled directly tothehostfacility,andun-coupled systems which in most cases are connected to the host by flexible jumpers and are increasingly being applied in recent deepwater and ultra-deepwaterfielddevelopments.

Subsea 7 continues to develop innovative un-coupled riser concepts designed for harsh and challenging environments.

HRTs

HybridRiserTowers(HRTs) are recognised to have significant benefits for deepwater riser applications in termsofflowassurance,thermalperformance and robustness of layout.Thislatterissueisespeciallysignificant when a large number of risersareconsidered.AnHRTprovidesthe required flexibility by avoiding a crowded layout and allowing a progressivedeployment.Theconceptis applicable to deepwater and ultra-deepwater,andtospread-mooredandturret-mooredFPSOinstallations.

ThefirstHRTapplicationinstalledbySubsea 7 was Girassol in Angola for Totalin1998.Thefield,incorporatingthreeHRTs,hasbeenproducingforover ten years to the specified stringent flowassurancerequirements.

HRTshavenowbecomeacceptedasarobust solution for deepwater and ultra-deepwaterdevelopments.ThelatestSubsea7HRTtechnologyiscurrentlybeingappliedtoTotalsCLOVprojectsoffshoreAngolawheretwoHRTswillbeinstalledin2013.

BSR

The BuoyancySupportedRiser(BSR) system is being delivered by Subsea7fortheGuarandLulaNEfield development in Brazil under contract to Petrobras for installation in late2012/early2013.

TheBSRconceptconsistsofalargesub-surface buoy which is anchored totheseabedbyeighttethers,twooneachcornerofthebuoy.ThebuoysupportsmultipleSteelCatenaryRisers(SCRs)whichareconnectedtotheFPSObynon-bondedflexiblejumpers.

ThisBSRsystemabsorbsthedynamicsfromtheFPSO,resultinginalmostnodynamicstressesontheSCRs,makingthem behave like a long free-spanning pipeline with the major fatigue response coming from the Vortex Induced Vibrationduetothelocalcurrents.

Since there is very little dynamic responsefortheSCRs,mechanicallylinedpipeisusedfortheSCRsection,therebyoptimisingtheriserdesign.

COBRA

Subsea7smostrecentriserconceptis the CatenaryOffsetBuoyantRiserAssembly(COBRA),whichconsistsofacatenaryrisersectionwithalong,slender buoyancy module on top which istethereddowntotheseabed.SimilartothemultiriserBSR,thetopofthecatenary riser section is connected to thehostbyaflexiblejumper.

COBRA is a highly compatible riser arrangement for host platforms with largemotions,likeFPSOsorsemi-submersibles.

This riser concept has the advantages of excellent dynamic performance with littleornofatigueresponse,andcantherefore be designed for pipeline-classwelds.Thisthereforeallowstheuse of mechanically lined pipe where appropriate,asinthecaseoftheBuoyancySupportedRiser.

Other riser systems such as Grouped SLORandSingleHybridRisersarealsopartofSubsea7sun-coupledRiserportfolio.

For further information contact john.mair@subsea7.com

Hydrid Riser Towers (HRTs)

Catenary Offset Buoyant Riser Assembly (COBRA)

Buoyancy Supported Riser (BSR)

Buoyancy

SCR

Mooring lines

Jumper

The successful installation by Subsea 7 of three subsea separation units (SSUs), operated by Total E&P Angola, proved critical to the early completion of the landmark Pazflor project on Block 17, offshore Angola. The challenging project involved the worlds first deployment of vertical SSUs to separate the oil, gas and water produced from Pazflors Miocene reservoirs.

Installing each SSU (weighing in excess of1,000t,includingsuctionanchors)required an unprecedented level of precision in water depths around 800m and a close working relationship with TotalandtheSSUmanufacturer,FMC,to ensure the final design included offshoreinstallationrequirements.

Operational requirements necessitated exceptionally tight installation tolerancesof+/-0.5fromhorizontalwhen installing the cluster of four suctionanchorfoundations.Toachievethistarget,Subsea7developedtheliftingarrangement,andinterfacedwithFMC to accurately operate the levelling systembasedondifferentialsuction.

Earlyanalysesshowedariskofresonance of the subsea hardware duringlowering,potentiallyleadingtosignificantweathersensitivity.Tomitigatethisissue,Subsea7developeda real-time monitoring system receiving acceleration data from sensors located on the crane tip and on top of the hardwareastheywerelowered.

Extensivedryandshallowwatertestingin Norway allowed the team to test the SSU installation before the units werefinallytransportedtoAngola.WorkingincloseliaisonwithFMC,Subsea 7 coordinated transportation and designed a specific sea fastening tominimisefatigueoftheSSUs.PriortodeploymentonsitebySubsea7sinstallation vessel the Acergy Polaris,thestructuresintegritywasre-testedinLuandabay.

Connecting each SSU to the subsea manifold was a complex and delicate operationinwhichtheROVoperatorshad to first remove caps from the

Planning and precision combine on Pazflor

manifold followed by the operation of ajackingsystemtoslidethe400t,six-storey high SSU towards the manifold to matethreeconnectionssimultaneously.

The Seven Eagle performed the SSU umbilical installation and the tie-in of the firstpairoffourmulti-phasepumps.

Thelandmarkproject,inwhichfirstoil was achieved ahead of schedule including the development and installationofnewtechnology,underlines the importance of effective interfacesbetweensuppliers,contractorsandclient.

Subsea 7 continues to develop new deployment systems including fibre-rope and active-heave compensation that are deemed essential in the deployment and retrieval of sensitive rotating machinery and processing systems in ever-increasing water depths ofthefuture.

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SSU shallow water tests in Norway

A Pazflor SSU being installed

Foundations

Inoursubseaconstructionbusiness,there is constant pressure to optimise foundation design to be as efficient as possible in terms of installation without compromisingfunctionality.

Subsea 7 has produced recent research at the highly respected Centre for Offshore Foundation Systems at the University of Western Australia into an optimised design methodology that has led to the possibility of reducing the size ofshallowfoundationssuchasPLETmudmatsby20%,oralternativelyabletowithstandlargerjumperloads.

The geotechnical engineer is always interested in finding the most critical failuremechanismofafoundation.

Subsea 7 has teamed up with the universitytodevelopanew3Danalysistool which could potentially halve the engineering hours spent designing foundationsundercomplexloading.

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DEEP7 May 2012

Groundbreaking geotechnicsIn 2011, Subsea 7 commenced accelerated development in the field of Geotechnics in two areas of great significance for our clients deepwater operations, how seabed soils and pipelines interact, and how an enhanced appreciation of soil behaviour and failure mechanisms can optimise foundation design, particularly for very soft deepwater clays.

Pipelines

Subsea 7 actively participates in the Safebuck series of JIPs - currently in its third phase - but we have also internally funded work investigating the dynamic embedment (and hence friction and stability)ofpipeslaidonsoftclayswhichare typically found at the deepwater sites wherewework.

Another key challenge being addressed is an improved understanding of the behaviour of carbonate sediments which are widespread in some developing oil andgas-richregionssuchasAustralia.

Carbonate-rich soils exhibit different behaviour to their non-carbonate counterparts,soSubsea7undertooka study to investigate the response of carbonate soils to cyclic pipe loads by model testing in a geotechnical centrifuge.

The results of this study are counter-intuitive to those predicted by classical soilmechanics,andtheworkrepresentsa significant step forward in evolving a new constitutive model to describe the behaviourofcarbonatesoils.

Looking to the future

Emergingchallengesinthegeotechnical industry are likely to include:

developingandimprovingthe constitutive model for carbonate soils and applying it to foundation and pipeline design

howtoquantifythedegradingeffects of solid hydrate and hydrate dissociation on soil properties

furtheroptimisationoffoundation designs as large and heavy processing facilities are moved subsea

developingdesignmethodsfor ultra-deepwater soils where soil strength is more dominated by viscous behaviour than traditional shear strength

findingnovelandeffectiveways to protect subsea infrastructure in the Arctic or ice-proneregions.

Mudmats for PLET applications

Model pipe set up for axial friction test

For further information contact paul.brunning@subsea7.com

Apparent friction derived from cyclic axial friction tests

FE analysis for optimised foundation design

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bridge supervisors on board the Seven Seas,inanenvironmentwithwhichtheyarealreadyfamiliar.

The simulations feature:

Variableseaconditionswhichcanproduce realistic motions of the Seven Seas(Subsea7sconstructionvesselonBlock31)

Seacurrentsthatcanbevariedin both strength and direction at different depths to replicate the currents throughout the entire 2,100mwatercolumn

TwoHerculesROVsystems,eachwith fully working manipulators and three selectable onboard cameras

Real-timeFEApackagecalculatingloadson,andMBRof,theflexibles

Twosubseawinchescompletewithworking line-out meters and load cells.

Cutting-edge simulationSubsea 7 has developed one of the most powerful installation simulation packages ever built, including unique finite element analysis (FEA) capabilities, and successfully installed the hardware on board construction vessel the Seven Seas for effective on-site operative training.

The programme was developed over a two-yearperiodfortheBlock31projectoffshoreAngola.Anunusualaspectofthis deepwater project is the mid-water pull-in of the flexible risers that connect theverticalriserstotheFPSO.Theseoperations are carried out at an average depthof200m,whichpresenteduncommonproblems.

Unlikemostpull-ins,thetasksareperformed in a situation where everythinginthescenarioismobile.TheUpperRiserAssembly(URA),whileweighingseveralhundredtonnes,canbe easily moved and rotated should the ROVpushit.Whentheflexiblerisersare attached to the subsea winch wires and the load transferred from the vessel cranetothewinches,theURA,whichinitselfisdynamic,tendstofollowtheriser lay direction for many metres - which has the potential to compromise theminimumbendingradius(MBR)oftheflexible.

Thesituationwasrisk-assessed,andit was decided that the risks could be mitigated by building the nine different scenarios (there are nine flexible risers)inasimulator.Thiswouldallowprocedurestobechecked,andalsofacilitatepilottraining.Thesimulationpredictions were shown to correlate well with measurements taken before and duringtheactualoffshoreoperation.

The development of the simulator though 2010 and 2011 pushed the pilot-training software and hardware well beyondtheirexistingcapacity,duetothe large number of flexible and moving objectsineachscenario.

Most simulation training takes place at Subsea7ssiteinAberdeen,butforthisproject it proved more effective to train theROVpilots,superintendents,and

The on-board simulator uses the existingHercules23controlconsole,withanadditionalsixpowerfulPCs.Aswitch disconnects the topside control systemfromtheROVandchangesoperationsfromnormalROVcontroltosimulation mode (this is only done when thevehicleisondeck!).

Block 31 installation simulator in use on board the Seven Seas

For further information contact mike.bramley@subsea7.com

The simulation FEA calculates the minimum bending radius of the flexible during ROV operations

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DEEP7 May 2012

Mechanically lined pipe extends reachSubsea 7s ground-breaking development work into the installation of mechanically lined pipe has recently been undergoing further qualification following the worlds first contract award to use BuBi mechanically lined pipe installed by the reel-lay method for the Guar and Lula NE pre-salt project in Brazil.

Working in collaboration with BuBimanufacturerBUTTING,Subsea 7 has already qualified BuBi mechanically lined pipe for reel-lay installation for flowlines and low-fatigue riser applications globally as a cost-effective alternative to solid corrosion-resistantalloysormetallurgicallycladpipe.Wearenowbroadeningtheproductsapplicationsintoareasofhigherpressureandfatigueapplications.

Current testing has demonstrated higher fatigue performance toDNVclassC/2atthetimeofprinttoextendtheapplicabilityof the technology to even greater water depths and more challengingdesigncriteria.

The rigorous fatigue testing programme included:

Manufactureofthreeteststrings(12girthwelds)comprisingcarbonsteelgradeX65fortheouterpipeandalloy625fortheliner,madeupofBuBi pipe sections welded together usingthemechanisedPGTAWprocess(seepage3)withalloy625fillermetal

Aconservativecyclicbendingtestorreelingsimulation,usingaradiusofcurvatureof7.5m

Resonancefatiguetestingofthestringpost-reelingsimulation.Theenduranceofthepipeanditsweldswasthus confirmed to achieve the minimum target level of fatigueclassC/2.

The full programme was performed in accordance with DNVQualification(DNV-RP-A203)andwaspreviouslyawarded the certificate for fitnessforservice.

AnextensiveNDEvalidationprogrammewasconductedbetween Subsea 7 and BUTTING to qualify the inspection technology(DNV)anddemonstratethecapacitytodetectanyminute defects in the pipe end overlay welds and seal weld at thetransitionbetweenlinerandoverlay.

The combination of the high-quality manufacturing process and inspection technology is fundamental to ensure the in-service reliabilityofthetechnology.

Subsea Hydrocarbon Sampling Skid (SHSS)Following the successful development of its Subsea Hydrocarbon Sampling Skid (SHSS), Subsea 7 is now able to offer clients ROV-deployed sampling from live production wells with zero emissions to the environment while maintaining full isothermic and isobaric conditions.

Hydrocarbon samples are required in order to determine fluid chemistry to enable calibration of the subsea flowmeter andpotentialfiscalallocations.TheSubsea7SHSStakesa true sample with no need to alter production flow or temperature.

It also takes samples from individual wells before they aremixedtogetheratmanifoldorFPSO,andenablesproduction samples or gases from individual wells to be analysedindependently.

The skid comprises the following key elements:

Anumberofsamplingcylindersallowingseveralsamplestobetakenfrommultiplelocations/wells

Acontrolledrateoffillandheatingsystemensuresthesampleistakeninanisobaricandisothermalmanner.

ThehostROVprovidestheskidwithpowerandtelemetry.

TopsidescontrolisviaarobustlaptopPC.

Aheatingsystemmaintainsthesamplecylindersandpipework at a sufficiently elevated temperature in order to mitigate the formation of hydrates during the sampling processanddissolvedgasescomingoutofsolution.

Afail-safeconnectiontoolensuresthesafeshutdownofthesampleinterfaceatthewellshouldtheROVexperienceavesselrun-offordeadvehiclesituation.

The SHSS is the latest in a long Subsea 7 tradition of developingpioneeringhigh-quality,cost-effectiveROVtooling,includingastandardrangeofmanipulator-deployedtools,componentchange-outtools,bespokeinterventiontoolsandskids.

For further information contact mick.fowkes@subsea7.com

The Welding Institute (TWI) Fatigue Test Rig

For further information contact gregory.toguyeni@subsea7.com

S-N curves showing the number of fatigue cycles reached to date on three test strings (RF1, RF2, RF3). No failure of the pipe or liner seal welds has been recorded at the DNV class C.

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TheSwagedEndConnectionhasalreadybeenwidelyusedbySubsea7onJ-layandS-layPIPprojects,butthisnewconceptrelatestoreel-layapplications.

TheSwagedEndConnectionisfabricatedbyswagingthepipeendsoftheoutersleevepipe,followedbyweldingtotheflowlineateachendofthefabricatedstalk,typically750mlongforreel-layapplications.Thesealedannuluswithinthestalkcan then have the pressure drawn down within the annulus off-lineinadvanceofreelingontothereel-layvessel.

Aseachstalkissubsequentlyreeledontothevessel,thePIPswaged end stalks are fabricated together by firstly girth-welding of the flowlines and the use of welded half shells for theoutersleevepipe.

TheSwagedEndConnectionsprimaryfunctionistoprovidethe following:

Aleak-tightsealfordraw-downofpressurewithintheannulus

Arobustmechanicalbarriertoactasawaterstopinallenvisaged water depths in the event that the outer pipe is breached,thuspreventingtheentirepipelineannulusfromflooding

Ameansofmechanicalconnectionbetweentheflowlineandoutersleevepipethatcanbereeled.

Testing and qualification has focused primarily on the following areas in order toattainDNVFitnessforServiceQualificationincompliancewithDNV-RPA-203: FEAmodelling Simulatedreelingandstraighteningtrials Weldingandinspection Post-reelingFEAanalysisusingstraindatacollatedfromthe

simulated reeling and straightening trials Materialtesting Annuluspressuretest

In collaboration with its development partner ITP InTerPipe, Subsea 7 currently offers the market its DNV-qualified Enhanced Thermal Performance Pipe-in-Pipe system for installation by the reel-lay method. This superior technical solution, which benefits from the combination of Izoflex insulation material in conjunction with a reduced pressure in the PIP annulus section, has recently been further enhanced by the development and qualification of the Swaged Field Joint.

Svalin C reeled PIPSubsea7sexpertiseinhighperformancePipe-in-Pipe(PIP)installationscoversfull-scopedesign,procurement,constructionandinstallation,andextendstoover40successfulPIPprojectsincludingbundletechnology,S-lay,J-layandreel-lay.

Ourlatestprojectcomprisesa5-inch/8-inchgasliftPipe-in-Pipe,tobedesigned,constructedandinstalledfor Statoil between the Svalin C Template and the GraneplatforminthecentralNorthSea.Thecontractalso covers the installation of the Svalin C template and manifold,ahighlywet-insulatedproductionflowline,andanumbilical.

In addition to our market-leading versatility in the installationofhighperformancePipe-in-Pipe,Subsea7canalsoinstallelectricallytrace-heatedflowline(ETHF)PIPsolutionsbyreel-layorintowedbundles.

ETHFtechnologyhasbeensuccessfullycommercialised by Subsea 7 in partnership with manufacturer ITP InTerPipe to combine high-performance thermal insulation with low-power resistive heatingelements.NowtechnologicallyqualifiedbyDNVforreel-layinstallation,ETHFoffersahighlyefficient means of maintaining product temperature in themostchallengingsubseaenvironments.

Flowline

Sleeve Pipe

Enhanced Thermal Performance PIP incorporating Izoflex insulation material with reduced pressure and no centralisers in the annulus section

Swaged end connection for reel-lay high performance pipe-in-pipe

For further information contact paul.booth@subsea7.com

Pipe-in-Pipe cross section

FE analysis

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Fleet development update

With its pipelay and heavy-lift capabilities,Subsea7sSeven Borealis is possibly the most versatile offshore construction vessel.Its5,000tcrane,withthe top of the mast reaching 150mabovethemaindeck,istheworldslargestoffshoremastcrane.Recentlifttests in Singapore proved its capabilityoflifting5,000t.The Seven Borealis joins the fleet in the second half of 2012.

New-build Seven Borealis

Subsea 7s industry-leading commitment to fleet development is directly driven by our identification and anticipation of our clients needs for their increasingly challenging subsea field developments.

Whetherforhighlycomplexdeepwaterinstallations,extendedLife-of-Fieldoperationsorenhancedweldingperformance,Subsea 7 is committed to working in close collaboration with our vessel-build and equipment partners to incorporate client requirements in the design of new vessels and upgrading of existingvessels.

Thefivenewvesselsprofiledhereallreflect,intheirdifferentways,elementsofourcommitmenttodeployafleetof

Subsea7hasbeenawardedacontracttoprovidea550ttop-tensionPLSVforPetrobrasfordeliveryin2014.Thistop-tensioncapabilitygivesthevesselSubsea7shighest-performingflexiblepipelaycapabilityinthefleet,andamong

New-build flexible pipelay support vessel (PLSV)

unrivalledcapacityandversatility,andonewhichoffersourclientsaccesstoover40vesselswiththehigheststandardsofflexibilityandprojectreliability.

Enhancedvesselspecificationslikecraneandmoonpoolcapacities are designed to accommodate the hardware which weplantodeployforthefutureinsupportofourclients.

Thisisparticularlyevidentinourlatestflagshipenablingvessel,the Seven Borealis,whichnotonlyfeaturesworld-leadingliftingcapabilities,butwillalsoincorporateSubsea7slatestmechanised welding technologies on its J-lay and S-lay firing lines(seepages2and3).

thehighestforanyPLSVintheworld.Thishighspecificationreflects the existing and anticipated demand of Brazilian ultra-deepwateroperations.Thevesselisscheduledtohavea550tTiltableLaySystem(TLS)installed,withtwo275tretractabletensionerstohandleflexibleproductsbetween100mmand630mmouterdiameter.The tower can tilt to 10o when operational to recover rigid pipe fromtheseabedbutitcanalsotiltto50o from the vertical to allowtheTLStoclearpowercablesacrosstheentrancetoVitoriaharbour.

The two underdeck carousels will also be of the open-top basketdesign.ThenewPLSValsoincorporatesanumberoffurther design innovations to meet the specific requirements of theBrazilianmarket.Thevesselwillbefittedwithunderwaterdemountable thrusters which can be removed and replaced whilethevesselisafloat.

Seven InaghaSubsea 7 has an impressive track record in developinginnovativeequipment,andthisisconfirmedbyanewvesseljoiningthefleetin2012.The Seven Inagha started her life in 2011 as a high-capacityGulfofMexicoliftboat.Duringherconstruction,shewaspurchasedbySubsea7andbegan her conversion into an extremely capable platformforhook-upoperationsinWestAfrica.

The Seven Inagha is effectively a vessel with legs,and,unlikemostconventionaljack-ups,canmobilisetoaworksiteunderherownpower.She has an impressive lifting capacity with two 295tcranesfitted,andwillcommenceoperationsoffshoreNigeria.Withenhancedfacilitiesabletoaccommodateupto150peopleonboard,shewillprovide utility services and support to hook-up teamsonoffshoreinstallations.

Thethreeeye-catchingtubular97.5mlegshavepairsofrackswhichallowthe36planetarymotorstojackthehullataspeedof2.4mperminute,elevating the hull to a maximum height of 88m abovetheseabedinwaterdepthsofupto76mwhenoperatinginhook-upmode.

Seven VikingDueforlaunchinlate2012,theSeven Viking is designed as a next generationInspection,MaintenanceandRepair(IMR)vessel,withenhancedseakeepingqualitiesandenvironmentalperformance.TheSeven Viking will enter a long-term frame agreement with Statoil for operationsintheNorth,NorwegianandBarentsSeas.

The Seven Viking incorporates a number of design features to minimise mobilisationtimesandoptimisetransitspeeds,mostnotablyaninnovative hull shape which offers increased foreship volume and slenderwaterlines.Aswellasofferingimprovedseakeepingcapabilities(fullyoperationalin5msignificantwaveheight),thisdesignalsoprovidesalargerworkingdeckarea,witharaisedfreeboardandworkingstationsenclosedinaheatedindoorhangartoenableIMRoperationsinroughseasandextremetemperatures.

Other innovations which facilitate harsh weather operations include a skidding module handling system to store and move up to eight different modulesintothemoonpool,eliminatingtheriskofhangingloads,andde-icefacilitiesandastrengthenedhullforoperationsinArcticareas.

Seven HavilaThestate-of-the-artdivingsupportvessel,theSeven Havila,whichisownedbySubsea7andHavila Shipping and is widely considered to be the most advanced vessel of its type in the world,hasachieveda world first by simultaneously deploying eight saturation divers fromasinglevessel.

The advanced diving systemonthevesselincludesaten-chamber,24-menfullycomputerisedsaturationsuite,with a double bell handling system capable of workingdownto400mandupto6msignificantwaveheight.

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www.subsea7.comDEEP7 May 2012Subsea7,2012.Informationcorrectattimeofgoingtopress.

Subsea 7 has recently invested in two high-performance subsea ploughs that will significantly enhance our delivery capability on the burial of trenched pipelines.

OurnewVariableMulti-PassPlough(VMP),asthenamesuggests,hasthecapabilitytoperformanumberofpassesthroughtheseabedtoachievethespecifieddepth.However,where the VMP has a significant advantage over other ploughs isinitsabilitytoalteritscutdepthwithoutrecovery,therebyreducingoperationaltimings.

AnotherdesigninnovationistheVMPsfore-cutter,infrontofthemaincuttingtool,whichenablesthisploughtofunctioninstiffersoilconditions.

TheVMPalreadyhasaproventrackrecord,completinganextensive variety of pre- and post-cut trenches in varying soil

New multipass and backfill ploughs

Backfill Plough 2Variable Multi-Pass Plough

Autonomous Inspection Vehicle (AIV) commercialisedFollowing extensive in-water testing in 2011, the final software systems and design adjustments on Subsea 7s pioneering Autonomous Inspection Vehicle (AIV) have been implemented, and this game-changing technology is now being successfully commercialised.

The Mark 1 inspection-class vehicle is being deployed into customer qualification programmes during2012,andthedevelopmentpathsofthenextgenerationsoffullycapable,work-classsizedinterventionvehiclesarealreadybeinglaid.

A differentiating element of the AIV is its ability to recognise and respond to its surroundings - it will correct its trajectory in realtime,basedontheinformationitgathersfromitsonboardsensors.Thislevelofintelligenceanddecision-makinghashadtobede-riskedandmadeasrobustaspossible,soapowerfulvirtual reality simulator was used to ensure that every option was identifiedandassessed.

Incollaborationwithoneoftheworldsleadingunderwatersimulatorsuppliers,adetailedspecificationwasdevelopedtoallowhardware-in-the-looptesting.Thefinalsystem,probablyoneofthemostsophisticatedinexistence,allowsthe real AIV computational hardware to control a dynamic simulation model of the AIV within a virtual world that containsafull3Drepresentationofanoffshoreoilfield.Thispackage provides full emulation of the sensor packages and simulation of the vehicle dynamics operating around representativesubseainfrastructure.

Although this simulation uses a bank of some of the fastest industrialcomputersavailable,itallowsAIVmissionstobe run hundreds of times to ensure that the AIV decision-makingbehaviourisrobust.

The visual inspection capability of the AIV Mark 1 will lead to more cost-efficient and effective integrity management throughoutthelifetimeofasubseafielddevelopment.

As customer qualification of the visual inspection vehicle proceeds,Subsea7issimultaneouslyengagingwithsubseadevelopers,industrybodiesandfielddevelopmentstrategists to explore how autonomous technology can further enhance the challenging subsea operations of the future.

conditionsaroundtheworldforlarge-diameterpipelines,trucklinesandflowlines.

TocomplementtheVMP,Subsea7hasalsoinvestedinaBackfillPlough(BFP),whichredepositsthesoilfromtheVMP-cuttrenchbackintothevoidoncetheproductislaid.Theability to provide a quality backfill with the BFP significantly enhances both the thermal insulation and resistance to upheavalbuckling.

The ploughs have already been deployed by another recent addition to the Subsea 7 fleet - the highly versatile Skandi Skansenwhich,witha250theave-compensatedcrane,a300tA-Frameandabollardpullof350t,isideallysuitedtosupportmanyfieldinstallationoperations,includingploughingcampaigns.

For further information contact farquhar.mitchell@subsea7.com

For further information contact hugh.ferguson@subsea7.com

AIV deployment system