L06 - PIPELINES & FLOWLINES

L6 - FLOWLINES & PIPELINES •

PIPELINE & FLOWLINE DESIGN

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

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PIPELINE TIE-INS

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TRENCHING

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ROUTE SELECTION & SURVEYS

OIL EXPORT

GAS EXPORT

Hydraulic/Chemical Umbilical

Electrical umbilical

14” Water Injection

3”Service Seabed

12” 12” 6” Production Test

PRODUCTION PLATFORM

8” Gas Lift

Electrohydraulic Seabed umbilical

SUBSEA DEVELOPMENT SCHEME

10” Water Injection”

8” Production 8” Production

8” Water Injection

Electrohydraulic umbilical Seabbed

12 Well Template

SUMMARY - PIPELINE DESIGN REQUIREMENTS Flow Assurance Issues ( Module 1) Strength y Hydraulics – incl. Two-Phase Flow y Stability – Laying y Welding y Installation – Laying y Towing y Trenching y Upheaval Buckling y Corrosion

Multiphase Flow in Flowlines

Installation

Further Aspects to considers : y Inspection y Monitoring y Intervention y Repair y Abandonment Inspection

PIPELINE / FLOWLINE ROUTE SURVEY y DESIGN y CONSTRUCTION y AS-BUILT y OPERATIONAL

MALAMPAYA Gas Field Pipeline Route

Seabed Bathemetry

Side 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 Technology Conference. The vertical reel, with the adjustable stern ramp, allowed the lay angle to be increased or decreased depending on water depth and pipe properties. The preliminary design 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.

APACHE REEL SHIP RANGE OF RAMP ANGLES 18 – 70 Degrees

MAIN REEL Pipe Dia Length 4” 100 Km 6” 64 Km 10” 24 Km 14” 12 Km 16” 6 Km

320 REEL Pipe Dia Length 2” 50 Km 4” 13 Km 6” 7 Km 200 REEL Pipe Dia Length 2”

19 Km

4”

6Km

COMPARISON OF PIPELAY VESSEL CAPABILITY ON A SINGLE REEL Pipeline diameter (ins) 18 16

DeepBlue

14

12

10

Skandi

8

6

Ugland Reel

Apache

4

Apache 11

Norlift 2

0 0

10

20

30

40

50

Length (km)

60

70

80

90

100

110

120

FLOWLINE BUNDLES

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

1. Towhead 2. Bundle 3. Tow off Beach

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

FLEXIBLE PIPE

BASIC PRODUCTION FROM STEEL TAPES AND EXTRUDED PLASTIC

FLEX INSTALLER VESSEL

LAYING FLEXIBLE PIPE

VERTICAL LAYING

HORIZONTAL LAYING

ANCHOR ACTION AN ARMOUR BACKFILL PROTECTION FOR OFFSHORE PIPELINES FULL PENETRATION FLUKE ANGLE CHANGES STANDARD 140 - 200 LB/FT3 CONCRETE PIPE LAYING ON SURFACE

HIGHER STRENGTH CONCRETE ARMOUR COATING STANDARD TYPE 1 BURIED

1

FLUKE REMOVED FROM BOTTOM

3

2

ANCHOR WALKS ON BACKFILL

STANDARD CONCRETE TYPE 1 WITH CONCRETE (SET ON) ARMOUR COVER

STANDARD CONCRETE TYPE 1 WITH ENGINEERED ARMOUR BACKFILL 4

EXTRA STEEL

5

SPECIAL REINFORCING ARMOUR CONCRETE

6 7

SHAPED ARMOURED SECTION B

HAZARD OF PIPE BEING HIT BY FISHING EQUIPMENT Fishing Trawler

Free Span Point of contact Trawl boards making contact with a pipeline span are less likely to come free when hitting at an angle FLAT OTTER BOARD

PIPELINE / FLOWLINE WITH FREE SPAN

FLEXJET 11 - Small Pipe Burial Vehicle

Pipe Tracker Location System

Pipe Drops to bottom of Trench Backfill Pre-Laid Pipe High Pressure Cutting Jets Fluidise soil Low Pressure Jets excavating soil away from jetting arms

ROCK DUMPING