Overview of SURF Systems & Analysis

1. presentation introduction Presenter: Tarun Rewari Director – Aryatech Marine & Offshore Software: OrcaFlex What does SURF mean? S Subsea construction U Umbilicals R Risers F Flowlines Overview of SURF Systems & Analysis Aryatech Marine & Offshore Services

2. Define a deepwater system Aryatech Marine & Offshore Services

3. ‘deepwater’ marine systems Deepwater marine system Floater system Whatever we call it (and plenty of definitions), these systems are not rigidly connected to seabed. They have a ‘floater’ with ‘lines’ between floater and seabed  Redefine as Define a ‘Deepwater System’ Aryatech Marine & Offshore Services

4. ‘deepwater’ marine systems Though clearly important and linked, this presentation focuses on the design and analysis of SURF systems Define a ‘Deepwater System’ Floater SURF  Reservoir Aryatech Marine & Offshore Services

5. ‘deepwater’ marine systems Floater systems range in water depth: 10m <> 2000m Water Depth Aryatech Marine & Offshore Services

6. ‘deepwater’ marine systems Design Life • There are a variety of time frames (though no rigid distinction): • Permanent systems (life of field, ≈25 years) • Temporary systems (temp operations, few months) • Installation (construction / decommissioning, few hours, maybe a day) • Analyses and main components are similar. • Main differences: env. return periods, acceptance criteria Aryatech Marine & Offshore Services

7. Main System Components Aryatech Marine & Offshore Services

8. main system components Main Components • Floaters SURF top end boundary condition with various functions. (FPSOs, Semi-submersibles, TLPs, SPARs, offloading shuttles, drilling, installation / decommissioning) • Moorings multi-component wire, chain, polyester used to keep floater on-station. (spread, turret, SPMs, ‘jetty’, catenary, taut, hawsers) • Risers dynamic pipe (or pipe assembly), to transfer production or injection fluids, control fluids or lift gas between seafloor and floater. (SCR, TTR, flexible, hybrids, export systems (incl. hoses), flexible jumpers) Aryatech Marine & Offshore Services

9. main system components Main Components • Umbilicals Assembly of hydraulic hoses used to control subsea structures from a host. Loaded statically and dynamically. (power, control, chemical injection, hydraulic fluids, etc) • Flowlines static flexible pipe on seafloor for transportation of production or injection fluids. (Generally infield, linking subsea structures, or to a production facility. 100’s m < length < several km) • Jumper short pipe connecting flowlines and (flexible or rigid) subsea structures or close subsea structures. Loaded statically &dynamically Aryatech Marine & Offshore Services

10. main system components Main Components • Installation lower to seabed (‘payloads’, anchors, etc) lay flow- & pipelines (J-, S- & reel-lay) pre-lay risers & moorings vessel hook-up floatover heavy lift pipelay vessels, barges • Also recovery for repairs and re-installation, and decommissioning for permanent removal Aryatech Marine & Offshore Services

11. main system components Main Components • Other parts: bend stiffeners tapered stress joints mid-water arches (MWAs) riser towers, riser tethers anchors cranes / winches / tensioner systems payloads (PLETs, PLEMs, BOPs, etc) J-tubes stingers & rollers moonpools buoyancy modules & clump weights drag chains Aryatech Marine & Offshore Services

12. main system components Turret moored FPSO Semi-submersible TLP SPM Main Components – ‘flexibles’ export lines jumpers transfer lines riser tower risers mid-water arch buoyant ‘steep’ wave flowlines Aryatech Marine & Offshore Services

13. main system components Main Components – ‘rigid lines’ Aryatech Marine & Offshore Services

14. main system components Main Components - installation Floatover Jacket launch Recovery / re-installation • Colin Lewis to supply some nice OrcaFlex screenshots of some of the components on the previous slide. S-lay Lower to seabed Pull-in Load transfer Aryatech Marine & Offshore Services

15. Main Analysis Steps Aryatech Marine & Offshore Services

16. main analysis steps High level main systems design loop In principle a strong feedback loop, though in practice, analysis does not often reflect this Both Concept Selection and main Engineering Design Floater Moorings SURF Installation Main Analysis Steps Aryatech Marine & Offshore Services

17. main analysis steps For floater, moorings, SURF and installation, some or all of the following required: Main Analysis Steps Concept design Static load screening Installation VIVanalysis Acceptabledesign Fatigue Interference analysis Extremedynamics Aryatech Marine & Offshore Services

18. mainanalysissteps Main considerations: costs regulatory issues existing infrastructure floater availability environment reservoir characteristics Initial evaluation often done through proprietary scenario simulators to evaluate production from different options Concept / FEED Aryatech Marine & Offshore Services

19. Acceptance Criteria for ‘lines’ Aryatech Marine & Offshore Services

20. acceptance criteria, rules & regs Once analysis completed, results are then assessed against various acceptance criteria: Internal loads (components, buckling, utilisation, end loads) Interference (clearances with other items) Fatigue (predicted vs. life of field) Above to be checked for all systems (moorings, SURF and installation), though some detailed checks may not apply to all Acceptance Criteria Aryatech Marine & Offshore Services

21. acceptance criteria, rules & regs Philosophy varies from code to code Focus on two different methods for structural design Working Stress Design (WSD) Limit State Design/Load and Resistance Factored Design (LRFD) Design Philosophy Aryatech Marine & Offshore Services

22. acceptance criteria, rules & regs There are many different codes covering several applications: Dynamic Systems Codes Codes specific to Rigid Risers Codes specific to Flexibles (umbilicals, risers, hoses) Codes specific to Mooring (incl. anchors) Codes specific to Installation (including pipelay, heavy lift, etc) Codes in Common Use Aryatech Marine & Offshore Services

23. Floater Types Aryatech Marine & Offshore Services

24. floater types Hull Forms Permanent: But must also remember wide variety of ‘temporary’ floaters associated with field construction, repair and decommissioning – installation vessels, barges, offloading vessel, pipelay, crane lift, transportation Aryatech Marine & Offshore Services

25. floater types Existing GoM Floaters Aryatech Marine & Offshore Services

26. floater types Free floating hull many variants catenary or taut moorings anchors vertical or catenary risers Columns Bracings Pontoons Semi-submersible Hull Aryatech Marine & Offshore Services

27. floater types Ballasted hull keeps tendons in tension Tension minimises heave Inverted pendulum Springing / ringing & setdown Tension Leg Platform (TLP) Aryatech Marine & Offshore Services

28. floater types Vertical column floater First spars had solid hull 2nd generation truss hull 3rd generation cell hull Mooring similar to semi-sub VIM & 2nd order vertical motions SPARs VIV strakes Aryatech Marine & Offshore Services

29. floater types Shipshape Hull Conventional spreadmoor Single point mooring outside of hull Single point mooring contained in hull Aryatech Marine & Offshore Services

30. floater types Deck Mating as fixed platform – but with moving hull Spar – Loadout and Tow / Upending Shipshape – towed Semisub/TLP – heavy lift vessel Hull Installation Aryatech Marine & Offshore Services

31. Mooring & Anchoring Systems Aryatech Marine & Offshore Services

32. mooring & anchoring Re-cap on main types catenary or taut spread or single point (weathervaning) temporary or permanent Mooring line seabed end termination is a fixed location vessel end termination moves with vessel weight controlled thru materials (chain, wire rope, synthetic rope) accessories (links, eyes, shackles, sockets, fairleads, winches, stoppers) Anchor types drag embedment suction caisson Mooring Systems Aryatech Marine & Offshore Services

33. mooring & anchoring Catenary vs. Taut Mooring Aryatech Marine & Offshore Services

34. mooring & anchoring 75 ft Anchor Types • Deadweight (gravity base) • Piling (driven) • Drag embedment anchors • Suction anchors • Vertically loaded anchors (VLA) • Suction Embedded Plate Anchor (SEPLA) Aryatech Marine & Offshore Services

35. mooring & anchoring Additional Mooring Components • Buoys • may be in-line or attached to the line • provide buoyancy to reduced load on platform • add compliance to a mooring line • generally kept below surface to avoid additional wave loading • Sinker weights and Deadman • additional clump weights added to lines • weight line down (invert catenary) • sinker weights in water column • dead man on seabed – similar to gravity base anchor Aryatech Marine & Offshore Services

36. mooring & anchoring Mooring Design Codes • Most common • API RP2SK – Rules for Station Keeping (mooring line and anchors) • API RP2SM – Synthetic mooring lines • DNV-RP-E301 – Position Mooring • Additional for anchors • DNV-RP-E303 – Design and Installation of Suction Anchors In Clay • DNV-RP-E302 - Design and Installation of Plate Anchors in Clay • DNV-RP-E301 - Design And Installation Of Fluke Anchors In Clay • Codes apply different factors of safety for • distinguish between permanent vs. mobile mooring • intact and damaged condition • quasi-static vs. dynamic analysis Aryatech Marine & Offshore Services

37. mooring & anchoring Anchor Proof Test • For the analysis • mooring line analysis gives loads at seabed fixed point • demonstrate anchor can achieve a prescribed load • For the installation • vessel pull on mooring line for period of time • demonstrates that anchor can take intended loads Aryatech Marine & Offshore Services

38. Risers Aryatech Marine & Offshore Services

39. riser systems Riser Systems • Transportation of production hydrocarbons and other fluids between seabed and floater • oil/gas – import or export, reinjection • water – export, injection • Drilling and work over operations (may also contain hydraulic lines or electrical lines) • Can be bundle (several lines in one carrier pipe) • Can be a pipe-in-pipe • May be added to a facility after initial installation (eg, tieback from new wells) Aryatech Marine & Offshore Services

40. riser systems Common Configurations Aryatech Marine & Offshore Services

41. riser systems Riser Systems – pros & cons Aryatech Marine & Offshore Services

42. riser systems Riser Systems – pros & cons Aryatech Marine & Offshore Services

43. riser systems Riser Systems – pros & cons Aryatech Marine & Offshore Services

44. riser systems Riser Systems – pros & cons Aryatech Marine & Offshore Services

45. Umbilicals Aryatech Marine & Offshore Services

46. umbilicals Umbilical Applications • Transfer hydraulic and electrical power • Data logging (electrical or fiber optic) • Chemicals for well control (methanol) • Transfer between floater and seabed • Transfer between wells and manifolds Aryatech Marine & Offshore Services

47. Tarun Rewari Director - Aryatech Marine & Offshore www.aryatech.net