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

Define a deepwater system Aryatech Marine & Offshore Services

Define a ‘Deepwater System’ ‘deepwater’ marine systems Define a ‘Deepwater System’  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 Aryatech Marine & Offshore Services

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

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

‘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

Main System Components Aryatech Marine & Offshore Services

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

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

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

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

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

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

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

Main Analysis Steps Aryatech Marine & Offshore Services

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

Interference analysis main analysis steps Main Analysis Steps For floater, moorings, SURF and installation, some or all of the following required: Static load screening VIV analysis Extreme dynamics Interference analysis Fatigue Concept design Acceptable design Installation Aryatech Marine & Offshore Services

Concept / FEED Main considerations: main analysis steps Concept / FEED 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 Aryatech Marine & Offshore Services

Acceptance Criteria for ‘lines’ Aryatech Marine & Offshore Services

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 Aryatech Marine & Offshore Services

Design Philosophy Philosophy varies from code to code acceptance criteria, rules & regs Design Philosophy 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) Aryatech Marine & Offshore Services

acceptance criteria, rules & regs Codes in Common Use 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) Aryatech Marine & Offshore Services

Floater Types Aryatech Marine & Offshore Services

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 24

Existing GoM Floaters floater types Aryatech Marine & Offshore Services

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

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

SPARs Vertical column floater First spars had solid hull floater types SPARs 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 VIV strakes Aryatech Marine & Offshore Services 28

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

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

Mooring & Anchoring Systems Aryatech Marine & Offshore Services

Mooring Systems Re-cap on main types Mooring line Anchor types mooring & anchoring Mooring Systems 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 Aryatech Marine & Offshore Services 32

Catenary vs. Taut Mooring mooring & anchoring Catenary vs. Taut Mooring Catenary heavy in deep water line horizontal at seabed anchor subject to horizontal forces restoring forces by line weight Taut leg line non-horizontal at seabed anchor sees non-horizontal forces restoring forces by line elasticity smaller footprint than catenary mooring Aryatech Marine & Offshore Services

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

Additional Mooring Components 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

Mooring Design Codes Most common Additional for anchors 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

Anchor Proof Test For the analysis For the installation 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

Risers Aryatech Marine & Offshore Services

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

Common Configurations riser systems Common Configurations Aryatech Marine & Offshore Services

Riser Systems – pros & cons Aryatech Marine & Offshore Services

Riser Systems – pros & cons Aryatech Marine & Offshore Services

Riser Systems – pros & cons Aryatech Marine & Offshore Services

Riser Systems – pros & cons Aryatech Marine & Offshore Services

Umbilicals Aryatech Marine & Offshore Services

Umbilical Applications 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

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