Subsea Structures and Interfaces to Pipelines - Alvheim

Dag BurgosPipeline Design Supervisor

Seminar Subsea Production FacilitiesIngeniørenes Hus, 09.03.06

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Agenda

Alvheim – General Project Data

Field Layout

Subsea Structures

EPCI scope

Layouts

Design Issues

Installation Issues

Questions

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Alvheim – General Project Data

Client: Marathon Petroleum Company

Contract Value: 1 050 MNOK

Subsea Tie-back to FPSO “Odin”

Water Depth: 120 m

EPCI Contract:4 off Production Manifolds3 off Riser Bases incl. SSIVSage Tie-in skid75 km Sub sea pipelines ( from 4” to 14” )9 off Flexible Risers ( 10” – 12.5” ) 3 off dynamic Umbilical16 km Static Umbilical46 Spools ( diver tie-in )3 Riser Support systems (MWA)

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Field Layout

WPS

Manifolds

Riser Bases

PLEM

SAGE skid

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Alvheim Centre Layout

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Description of Subsea Structures

4 Manifolds:• Boa• Kneler A• Kneler B• East Kameleon

Almost identical

Tie-in Skid at SAGE (Scotish Area Gas Evacuation)

3 Riser Bases:• East RB• West RB• South RB

Water Disposal PLEM

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Main Subcontractors and Status

Manifolds

Riser Bases

Sage Skid

PLEM

Engineering

Genesis:Valves

CPI: Control system,

MPFM

Procurement

Other Components

NYMOGenesis

Fabrication

NYMO/MORSKA/Trelleborg

Installation

Technip

Ingenium

ABBREVIATIONS:

CPI = Company Provided ItemMPFM = Multi Phase Flow MeterPLEM = Pipeline End Manifold

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Spools at manifolds

Manifold

Spools

Pipelines

4 trees

Spools

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Manifold – view from FPSO side

W = 170Te (in-air)

(12m x 19m x 5m)

umbilicalsFuture tie-inpoints

Multi Phase Flow Meter

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Manifold – Well side

Jumpersto treesTie-in points

Spools to trees

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Manifold – roof removed

Diver access

umbilicals

Tie-in pointsPipeline spools

Trawl deflector

Pile guides (temporary)

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Weight/Dimension Optimization

Gravity based / Suction anchor foundationLoadsFunctional requirements

Deck width limitationsCrane CapacityDriven Pile solutionRemovable roof

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Design Conditions - Structural

Load-out

Skidding (jacking)

Transportation

InstallationLifting (SIMO)Piling

In-placeOperational loadsTrawling loadsDropped objectSeismic

Crane

CSO Deep Pioneer

SA

CS

an

aly

se

s

14Title and date of the presentation

ALVHEIM DEVELOPMENT PROJECT Offshore Seminar – Subsea Structure Installation

Lift-off & Overboarding

15Title and date of the presentation

ALVHEIM DEVELOPMENT PROJECT Offshore Seminar – Subsea Structure Installation

Lifting Analysis with SIMO

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Piling OperationStructure with pile loading

hammer

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Design Conditions - Piping

Design Pressure 200barDesign Temperature 65degSelfweightSpool tie-in loadsSpool operational loadsHydogen induced stress cracking

Supportreactions

Structural checkof supports andfoundation design

Caesar analysis

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Hydrogen Induced Stress Cracks

Fillet weld configuration

Anchor support

Duplex Piping:

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Questions