L6 - FLOWLINES & PIPELINES

• PIPELINE & FLOWLINE DESIGN

• LAY TECHNIQUES– LAY BARGE & LAY SHIP INSTALLATION– REEL SHIP INSTALLATION– “J” LAYING– REEL SHIP INSTALLATION– FLOWLINE BUNDLES– FLEXIBLE PIPE

• PIPELINE TIE-INS

• TRENCHING

• ROUTE SELECTION & SURVEYS

SUBSEA DEVELOPMENT SCHEME

12” 12” 6”Production Test

Hydraulic/Chemical Umbilical

14” Water Injection

Electrical umbilical

3”Service

Seabbed

8” Gas Lift

Seabed

Electrohydraulicumbilical 10” Water

Injection”

8” Production

12 Well Template

8” Production

8” Water InjectionElectrohydraulicumbilical

Seabed

GAS EXPORT

OIL EXPORT

PRODUCTION PLATFORM

SUMMARY - PIPELINE DESIGN REQUIREMENTS

Flow Assurance Issues ( Module 1)

StrengthHydraulics – incl. Two-Phase FlowStability – LayingWeldingInstallation – LayingTowingTrenchingUpheaval BucklingCorrosion

Further Aspects to considers :InspectionMonitoringInterventionRepairAbandonment

Multiphase Flow in Flowlines

Inspection

Installation

DESIGN

CONSTRUCTION

AS-BUILT

OPERATIONAL

PIPELINE / FLOWLINE ROUTE SURVEY

MALAMPAYA Gas Field Pipeline Route

Seabed BathemetrySide scan sonar and sub-seabed profiling for route planning

LORELAY PIPELAY VESSEL

BALDER

6 × 12m pipe welded on deck and lifted to “j” lay tower.

In-line Sled welded into line

APACHE – REEL SHIP (Note now replaced by Apache 11)

Apache was the first self-propelled vessel ever built for laying pipe from a reel. It used a vertical reel, a concept first introduced by Santa Fe at the 1975 Offshore TechnologyConference. The vertical reel, with the adjustable stern ramp, allowed the lay angle to beincreased or decreased depending on water depth and pipe properties. The preliminarydesign basis is for the laying of 16-inch, 12-inch, and smaller pipes in 800m of water. The reel has a certain capacity (See separate Table), but containing several 10’s of Km the pipe is normally laid in less than 24 hours.

MAIN REELPipe Dia Length 4” 100 Km6” 64 Km10” 24 Km14” 12 Km16” 6 Km

320 REELPipe Dia Length2” 50 Km4” 13 Km6” 7 Km

200 REEL

Pipe Dia Length

2” 19 Km

4” 6Km

RANGE OF RAMP ANGLES

18 – 70 Degrees

APACHE REEL SHIP

Pipeline diameter (ins)COMPARISON OF PIPELAY VESSEL CAPABILITY ON A SINGLE REEL

0 10 20 30 40 60 70 80 90 100 110 120

Length (km)50

16

14

10

12

6

2

4

0

8

18

DeepBlue

Skandi

Apache 11

Ugland Reel

Norlift

Apache

FLOWLINE BUNDLES

Bundles are welded under factory conditions, pre-formed into complete lengths and tested

The completed pipeline bundle is launched into sheltered waters of the bay, inspected and tested prior to towing out to the field

The drag on the chains during the tow causes the bundle to lift and “fly”through the water clear of the seabed

Final positioning of the bundle at the location is undertaken by winching the neutrally buoyant bundle to a predetermined point on the seabed prior to

stabilising and tying in by divers or ROV’s

FLOWLINE BUNDLES

1. Towhead

2. Bundle

3. Tow off Beach

BASIC PRODUCTION FROM STEEL TAPES AND EXTRUDED PLASTIC

FLEXIBLE PIPE

FLEX INSTALLER VESSEL

LAYING FLEXIBLE PIPE

VERTICAL LAYING

HORIZONTAL LAYING

HIGHER STRENGTHCONCRETE

ARMOUR COATING

3

EXTRA STEEL

STANDARD140 - 200 LB/FT3

CONCRETEPIPE LAYING ON

SURFACE1

STANDARDTYPE BURIED1

2

STANDARD CONCRETETYPE WITH ENGINEERED

ARMOUR BACKFILL4

1

76

STANDARD CONCRETETYPE WITH CONCRETE(SET ON) ARMOUR COVER

1

5

SPECIAL REINFORCINGARMOUR CONCRETE

SHAPED ARMOUREDSECTION

B

PROTECTION FOR OFFSHORE PIPELINES

ANCHOR ACTION AN ARMOUR BACKFILL

FULL PENETRATION

FLUKE ANGLE CHANGES

FLUKE REMOVED FROM BOTTOM

ANCHOR WALKS ON BACKFILL

FLAT OTTER BOARD

HAZARD OF PIPE BEING HIT BY FISHING EQUIPMENT

Trawl boards making contact with a pipeline span are less likely to come free when hitting at an angle

Free Span

Fishing Trawler

Point of contact

PIPELINE / FLOWLINE WITH FREE SPAN

FLEXJET 11 - Small Pipe Burial Vehicle

Pipe Tracker Location System

Pre-Laid Pipe

Pipe Drops to bottom of Trench

Backfill

High Pressure Cutting Jets Fluidise soil

Low Pressure Jets excavating soil away from jetting arms

ROCK DUMPING