:cInternational Association of Oil & Gas Producers :cc, OGP::OGP Marine Risks Workshop Proceedings :cc, OGP:. Deepwater Systems & Functional RequirementsMike Efthymiou, ShellDeepwater Systems & Functional RequirementsOGP Marine Risks Workshop, March2003Mike Efthymiou- Floater and Riser system concepts- Key system selection drivers- Key lifecycle risksSpar cost for 12 wells= US$416 millEurope17West Af rica36SEAsia35Brazil22GulfofMexico25West Af ricaSEAsia/AustraliaGulfofMexicoBrazilEurope Spar 15Semi 14TLP 16FPSO 90FPSOTLPSparSemisubmersibleFloating Production Systems 2003-2007- 135 new systems -1977 2002 :200 floating prod systems 2003 2007 :135 floating prod systemsCAPEX:US$ 70 billionReserves targeted : 30 billion boeTotal deepwater reserves est : 100 bill boe::International Association of Oil & Gas Producers :cc, OGP:,OGP Marine Risks Workshop Proceedings :cc, OGPSystem selection drivers Direct Vertical Access (DVA) or not ? can we reach reservoir from single location? do we need frequent well intervention ? Do we need storage ? Proximity to Pipeline Infrastructure ? Technical feasibility/Economics [water depth, Environ] Local regulation e.g. US Regulator did not allow FPSOYDVADry Tree Units Wet Tree UnitsDirect Vert access (DVA)Y DVAY FPSOWet tree DVADeep, small areal extent2,000mDVAShallow reservoir, large areal extent1,000mNon-DVA20kmAccessibility from single drilling centre3kmDeepwater Systems & Functional Requirements - Mike Efthymiou, Shell (:)::International Association of Oil & Gas Producers :cc, OGP:,OGP Marine Risks Workshop Proceedings :cc, OGPWorldwide Extended Reach Worldwide Extended ReachDrilling Experience Drilling ExperienceNatural Periods of structures in relation to wave excitiationSTIFFCOMPLIANT[F]=[M][A]Deepwater Systems & Functional Requirements - Mike Efthymiou, Shell (,):International Association of Oil & Gas Producers :cc, OGP:,OGP Marine Risks Workshop Proceedings :cc, OGPCost of Dry Tree Systems2000 1000 1500 500 05004003002001000.0Water Depth (m)Substructure Cost US$mill(Cost includes hull, risers and mooring; does not include topsides, integration & commissioning)(Topsides weight = 12,000T, 12 production risers)Dry Tree Systems Compliant Tower TLP: Tension Leg Platform Spar FDPSO: Multi-Function BargeDVA but no storageDVA+ some storageF: FloatingD: DrillingP:ProductionS: StorageO: OffloadingDVA+ Storage but mild environment only5 kmDeep Reservoir5 kmDeep ReservoirDeepwater Systems & Functional Requirements - Mike Efthymiou, Shell ():International Association of Oil & Gas Producers :cc, OGP:,OGP Marine Risks Workshop Proceedings :cc, OGPWet Tree Systems FPSO: Floating Prod Storage Offloading (ship) FPS: Floating production System (Semi) FSO, FSUNo storage 15kmShallowReservoirNakika, 2002, WD=1800mWorldwide except GoMstorageDRILLINGDVA Systems(dry trees)PRODUCTIONRISEREXPORT/(IMPORT)RISERFUNCTIONTLPSPAR SEMISUB FPSOT-T(Tensioners)T-T = Top-TensionedT-T(Buoyancy Cans)T-T(Tensioners)T-T(Tensioners + buoyancy )T-T(Buoyancy Cans)FlexibleSCR orHYBRIDFlexibleSCR orHYBRIDFlexibleSCR orHYBRIDSCR SCRN A Increasing Platform MotionNon-DVA Systems(subsea wells)SCR = SteelCatenaryRiserFlexibleor SCR gas export Classification of RisersDeepwater Systems & Functional Requirements - Mike Efthymiou, Shell (,):oInternational Association of Oil & Gas Producers :cc, OGP:;OGP Marine Risks Workshop Proceedings :cc, OGPAuger 93MARS 96RAM-POWELL97URSA 99 BRUTUS 2001Shell Focus on TLPsRepeatability benefits, learningsBrutus hull arriving at Corpus ChristiNear shore topsides integrationDeepwater Systems & Functional Requirements - Mike Efthymiou, Shell (o):oInternational Association of Oil & Gas Producers :cc, OGP:;OGP Marine Risks Workshop Proceedings :cc, OGPbest averageOil0510152025Auger MarsRamPowell Ursamb/d30AugerpredpredictedWell productivity improvementDeepwater Systems & Functional Requirements - Mike Efthymiou, Shell (;):International Association of Oil & Gas Producers :cc, OGP:,OGP Marine Risks Workshop Proceedings :cc, OGP$1600000.20.81.019870.40.61991 1995 1999 2003BrutusBongaNaKikaAugerMarsUrsaMalampayaRam-PowellShell focus on TLPs led to project successCost/boe/d of productionAugerNew Industry NeedsNeed to extend system capability in terms of water depth to 3000m, hot & sour, heavy crude, small fields . and maintain good safety recordDeepwater Systems & Functional Requirements - Mike Efthymiou, Shell ():International Association of Oil & Gas Producers :cc, OGP:,OGP Marine Risks Workshop Proceedings :cc, OGP VIV of TT risers and SCRs Due to high currentsExport riser on Auger suffered VIV in 02Design & Install strakes Spacing risers to avoid collision Increasing tension with w depth Challenges - TLP Tendon installation [time, VIV] Increase water depth capability of TLPSpar EvolutionClassic spar Truss spar Cell sparDeepwater Systems & Functional Requirements - Mike Efthymiou, Shell (,):cInternational Association of Oil & Gas Producers :cc, OGP::OGP Marine Risks Workshop Proceedings :cc, OGPSpar ChallengesSpar VIV in currents ~ leads to lateral oscillation& fatigue of mooringsHelical strakesBoth classic spar & truss spar w strakes exhibit VIVSpar Risers:heave and spar offset lead to rubbing of buoyancy cans against guides Fatigue on guides and other moonpol components Challenges Flexible Risers- Flexible riser integrity -Damage to outer sheath , sea water ingress , corrosion fatigue-Sour gas permeation may lead to lower fatigue life-Gas permeation may lead to liner collapse Tensile armourInternal pressure sheathCarcassOuter sheath- Singing Risers-High pressure, high velocity, dry gas flow may lead to high freq -acoustic vibrations which cause resonance and may excite-pipework on topsides and subsea -Asgard, Troll C, Schiehallion- Ageing of Rilsan PA11- hydrolysis~ Ebrittlement ~ C-Anasuria riser replacement +-API Tech Rep TR17RUG, 2003Deepwater Systems & Functional Requirements - Mike Efthymiou, Shell (:c):cInternational Association of Oil & Gas Producers :cc, OGP::OGP Marine Risks Workshop Proceedings :cc, OGPChallenges Mooring Conventional MooringUKOOA study by Noble Denton concluded:One FPSO line failure every 6 yrsCases of systematic damage to > 1 lineParticular problems at connectors & interfacesLong-term failure rates remain uncertain Synthetic moorings Damage during handling Long term integrity Particular problems at terminations FPSO Challenges Internal Tank Cracking- Fulmar FSU (CNS), + other - Cause : High mean stress, high cyclic stresses (fatigue)- Solution: Taking affected & adjacent tanks out of service, inspect and repair(tedious)-Trading tankers also suffer from this but for FPSOs -dry docking is difficult/expensiveBallast Tank Cracking Deepwater Systems & Functional Requirements - Mike Efthymiou, Shell (::)::International Association of Oil & Gas Producers :cc, OGP:,OGP Marine Risks Workshop Proceedings :cc, OGP-Turret Location -If >75% *hull Length from stern free weathervane-If turret ~ 65% *hull Length from stern thrusters required-Advantage: Lock turret and reduce wear of bearing & swivel -Disadvantage: more demand on thrusters & crewFPSO Challenges Turret LocationMike EfthymiouSchiehallion Slamming Damage - Nov 98Bow hit & damaged by a large steep wavePersonnel evacuated, production shut downfor 10 daysShell severely deformed, plate torn, water ingressFPSO Challenges Green Water on Deck &Bow Slamming Damage- Green Water damaged stairways, windows, cable trays, pipework-Retroactive repairs, model testing, MARIN JIP Foinaven Slamming Damage - 1999Deepwater Systems & Functional Requirements - Mike Efthymiou, Shell (::)::International Association of Oil & Gas Producers :cc, OGP:,OGP Marine Risks Workshop Proceedings :cc, OGPDamage Location (Section Through Bow)ForwardEquipmentRoomForwardSwitch RoomStoreFORECASTLE DECK - el. 35750SWITCH-ROOM DECK - el. 31500MAIN DECK - el. 27250No. 1 COTBHD atframe 74fr.86 fr.89STIFFENER DETACHED FROM DECK4.5mFLOORDEFLECTED100mmSHELL PUSHED IN AROUND 250mm.TEAR IN PLATING1.2.3.Mike Efthymiou 18/11/99Schiehallion FPSO Slam damageVFPSOhull Severe slamming associated with large & steep waves and bow pitching downwards into the wave Ships with a rounded bow more vulnerable to slamming Slamming may lead to very high localised force peaks (7.5 bar)Use compact sections Schiehallion design satisfies Class Rules for bow slamming Class Rules are inadequate for FPSOs Other FPSOs may suffer slamming damage if harsh environment and bow is roundedSchiehallion FPSO Slam damageDeepwater Systems & Functional Requirements - Mike Efthymiou, Shell (:,):International Association of Oil & Gas Producers :cc, OGP:,OGP Marine Risks Workshop Proceedings :cc, OGPRotating Turret MooringCrude loading direct to tankerOffloading Collision Risk Direct (Tandem) offloading with tug assistanceConsequenceProbability of failure One extra tug Redundant hawser0QRA to understand & quantify risksOffloading from spread-moored FPSO offshore W AfricaDeepwater Systems & Functional Requirements - Mike Efthymiou, Shell (:):International Association of Oil & Gas Producers :cc, OGP:,OGP Marine Risks Workshop Proceedings :cc, OGPPeople AssetsEnviron-mentRepu-tationSeverity012345NoinjurySlightinjuryMinorinjuryMajorinjurySinglefatalityMultiplefatalitiesNodamageSlightdamageMinordamageLocaldamageMajordamageExtensivedamageNoeffectNoimpactSlighteffectSlightimpactMinoreffectMinorimpactLocalisedeffectConsider-able impactMajoreffectNationalimpactInter-nationalimpactMassiveeffectALow LowMedium MediumHigh HighB C D ESerious SeriousRisk Assessment MatrixFrequencyEscalation10-6/yr10-1/yrrareConcluding Remarks 2003-2007 US$70 billion on Deepwater projects 2003-2007 targeting reserves of 30 bill boe Diversity of Floating Systems in response to different needs Need to extend system capability in terms of water depth,hot & sour, heavy crude, etc Incidents relating to : Green water, wave slam, mooring, riser, tank cracking, explosions, offloading Biggest threat: events with potential to escalate .. leading capsizingDry-Tree SystemsTLP, Spar Subsea SystemsFPSO+SS, Semi Deepwater Systems & Functional Requirements - Mike Efthymiou, Shell (:,):oInternational Association of Oil & Gas Producers :cc, OGP:;OGP Marine Risks Workshop Proceedings :cc, OGP