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ULTRA DEEP WATER PIPELINE CAPABILITIES
and CHALLENGES
Mons HaugeStatoil R&D
DEEP WATER AREAS
NORWEGIANSEA
– 17th: 900m– 18th: 1500m
CASPIAN– 600m
NIGERIA NNWA:– 1400m
BRAZIL– ~3000m
VENEZUELA– 300m– (1000m)
DEEP WATER PIPELINESCHALLENGING PROJECTS
Gazprom BlueStream 24"
Shell Mars 18"Shell Ursa 15"
Amoco Aquaba 30"
Exxon Diana 18"
Shell Auger 12"
NH Ormen L 30"
Nansen/Boomv. 18"BP/TFE/Marathon Canyon Express 12"
Shell Popeye 6"Petrobras Campos 10"
Petrobras Marlin 12"Petrobras Roncador 10"
Shell Na Kika 20"BP Mardi Gras 28"
Diana 20"
Allegheny 14"
ÅTP 42"
Europipe II 42"
TOR II 20"
Haltenpipe 16"
SNAM Transmed 26"
TOR I 16"
Zeepipe IIb 40"
Shell Malampaya 24"
Shell Malampaya 16"
Statpipe 30"
SNAM Sicily 20"
SNAM Mesina 20"
Shell Mensa 12"
Crazy Horse 28"
Caesar 24"
Okeanos 24"
Iran –India 20"
0
200
400
600
800
1000
1975 1980 1985 1990 1995 2000 2005INSTALLATION YEAR
Dep
th x
Dia
met
er2
J-layReelS-layPlannedStatoil
DIFFICULTY: (DEPTH x DIAMETER2)
THE RELEVANT TECHNOLOGIES TO INSTALL ANDOPERATE DEEP WATER PIPELINES ARE:
DEEP WATER CHALLENGES
• DESIGN FRAMEWORK• GEOHAZARD ASSESSMENT• DEEP WATER LAYING• MAPPING• FREE SPANS• SEABED INTERVENTION• HOT TAP AND REPAIR TECHNOLOGY• RISK MANAGEMENT & PROJECT
ORGANISATION
DEPTH ITSELF IS NOT MOST IMPORTANT
DNV PIPELINE RULES & GUIDELINES USED WORLD WIDE
STATOIL EXPERIENCE AND R&D HAS CONTRIBUTED TO THE DESIGNRULES AND REQUIREMENTS E.G.:
– Buckling capacity in service (HOTPIPE)– Free span fatigue assessment (FATFREE)– Integrated materials requirements and design rules
STATOIL DEVELOPS RULES PRIOR TO AND DURING CHALLENGINGPROJECTS E.G.
– Troll Oil– Åsgard Transport
THROUGH CO-OPERATION WITH DNV THE EXPERIENCE ISIMPLEMENTED IN THE DESIGN RULES
Challenge 1DESIGN FRAMEWORK
Challenge 2SLOPES / GEOHAZARDS
SLOPES (20–30O) + SEDIMENTS +EARTH QUAKES => GEOHAZARDS
SOLUTIONS•routing to avoid slides•quantify load on pipeline•assess risk
Soil investigations Geological models
SLOPE STABILITY•when does movement occur?•when => gross mass flow?•how far do slides move?
Challenge 3DEEP WATER LAYINGS-laying
– SubmergedWeight
– Deformationon stinger
– Sag bendcollapse
– Routingflexibility
J-laying– Pipe diameter– Sag bend
collapse
Statoil Experience with challenging pipeline projects– Statpipe, Zeepipe IIb, Europipe II: leading wrt. depth/size– TOR I: leading wrt. difficult terrain
DEEP WATER LAYINGJ-LAYING:
E. G. SAIPEM 7000, MODIFIEDCRANE BARGE
– J-ramp with main line welding,NDT and tensioners
– prefabrication of quad-joints(48m)
S-LAYING:
E. G. STOLT OFFSHORE LB 200– S-lay stinger– Prefabrication of double joints
Challenge 4SEABED MAPPING ANDPIPELINE ROUTING
ACCURATE MAPPING IS A PREREQUISITEFOR ROUTING AND DETAILED DESIGNMAPPING HAS BEEN CRITICAL FOR MANYPROJECTS
– Troll Oil (Troll to Kollsnes)– Åsgard Transport (Åsgard to Kårstø)– Vestprosess (Kollsnes to Mongstad)
RECENT AND ON-GOING DEVELOPMENTS– Seismic equipment for geotechnical
characterisation– Scanning of seabed surface– Autonome vechiles (AUV)
HUGIN 600, HUGIN 3000
VESTPROSESS VIDEO
RETURN MAPPING RETURN
Video-clip removed
Challenge 5FREE SPANS
SPANS MUST BE LIMITEDDUE TO RISK OF
– OVERSTRESSING– FATIGUE
SPAN ASSESMENT ISINTIMATELY DEPENDENTON MAPPING
Challenge 6SEABED INTERVENTION
Objectives– Reduce free spans– Ensure pipe stability and avoid upheaval or lateral buckling– Protect pipe for fishing gear
Technologies– Trenching (plough or water jet)– Rock dumping
Challenges– Intervention is costly and has environmental impact– Design for free lateral movements (HOTPIPE design) will reduce
amount of intervention work– Geotechnical impact of intervention work (e.g. shear strength after
trenching)
Challenge 7DIVERLESS HOT TAP AND REPAIR
PIPELINE RAPAIR SYSTEM (PRS)– Diver assisted system for North Sea
modifications and repair operated byStatoil
– Hot tap on prepared T established– Diverless operations established for
diameter up to 20”New challenges
– Maximum depth for diver assistedoperations will be reduced from 360–250 min 2005 (HSE policy)
– Deeper water operations– Hot tap on unprepared pipe– Diverless hot tap and repair for diameter
above 20”
PIPELINE REPAIR SYSTEM (PRS)INCLUDES :
COMPLETE REMOTE REPAIRSYSTEM FOR DEEP WATER
– PLUGS, CLAMPS, COUPLINGS– LIMITED TO 600m– IN REGULAR USE !
STATOIL IS OPERATOR OF THE INTERVENTION & REPAIRSYSTEMS AT THE NORWEGIAN CONTINENTAL SHELF
12” COUPLING (VIGDIS)
SUCCESSFULLY INSTALLED 07.04.2002 00:15
SUCCESSFULL SYSTEM PRESSURE TEST08.04.2002 10:00
42” REMOTE PLUG
12” REPAIR CLAMP
Challenge 8RISK MANAGEMENT AND PROJECT ORGANISATION
HOW TO BE COMPETITIVE ?IN-HOUSE TECHNICAL EXPERTISE ON CORE TECHNOLOGIES:– Pipeline design and installation– Materials and fabrication– Seabed mapping and pipeline routing– Geotechics and seabed interventionRISK MANAGEMENT OF LARGE, COMPLEX PROJECTS– Logistics– Hazards– Time scheduleCONTRACTING STRATEGY– Contract packages (not EPCI)– Interface responsibility
TOTAL LENGTH OF NORTH SEA GAS TRANSPORT PIPELINES: 6000 kmTYPICAL LENGHT OF PREVIOUS PIPELINE PROJECTS: 700 kmNEW PIPELINE FROM ORMEN LANGE TO ENGLAND: 1200 km
0 2000 4000 6000 8000 10000
0
10
20
30
40
50
60
70
Ener
gy lo
ss [%
]
PipeLNGElectricity MethanolGTL
The way forward:How to make pipelines competitive for longdistance transport ?
Is it possible to makepipelines attractive for largevolumes when the distanceexceeds 3000 km ?Is it possible to install largediameter pipelines at 3000-4000 m water depth ?
– Long distance transportwill in many cases requirecrossing of deep waterareas
– New resources are foundin deep water areas
GSm3/year
10.0
1.0
5.0
2.0
LNG
Gas to Liquids
PIPELINE
UNECONOMIC
1000 2000 3000 4000 5000
Electricity(HVDC)
Snøhvit
Åsgardtransport LNG
Gas to Liquids
PIPELINE
UNECONOMIC
1000 2000 3000 4000 5000
Distance from field to market - km
Electricity(HVDC)
SnøhvitFuture
pipelines
0.5
0.2
20.0Åsgardtransport
Case study:A 2800 km pipeline from Venezuela to Florida
4 different pipeline routes consideredMaximum water depth about 4000 mDesign pressure increased to 400 bargRequired inner diameter:
– 30 MSm3/d require approx. 28” ID (10 GSm3/year)– 60 MSm3/d require approx. 36” ID (20 GSm3/year)
Limitations for J-vessels with an available tension forceof 1050 tonnes: (current vessels have 525 tonnes, but can easily beupgraded to 1050)
40040140030240024
360020
Water depth(m)
Diameter OD(inches)
Alternativepipeline routes
Florida
Venezuela
Haiti
Cuba
Puerto Rico
DominicanRep.
New solutions 1:Pipe-in-pipe with structural filler material
A ”sandwich” composite structure made of two concentric pipes with afiller material in between will increase the external pressure capacitysignificantly, and less steel is needed for the same capacity.As the total volume of the pipe increases, the submerged weight will alsodecrease (as long as the filler material has density below 1000 kg/m3)The capacity is directly depending on material strength (X70 is assumed incase study)
This concept leads to reduced tensionon the installation barge
M M
P
x
y
P
x
y
fys
fys
fyf ⇒ Mp
Pipe-in pipe filler materials
Polymers and polymer foam (polypropylene)– Used for thermal insulation– Low weight (900 kg/m3 for solid PP)– Low stiffness (E = 1,5 GPa for solid PP )
Concrete– Used for weight coating of pipelines– High weight (2500 kg/m3)– High stiffness ( E > 20 GPa )– Very cheap 75 $/m3
Lightweight concrete– Low weight (800 - 1000 kg/m3)– Moderate stiffness ( E = 4 – 7 GPa)– 225 $/m3
Pipe-in pipe cost estimate
Material cost for a sandwich pipe-in-pipe will be approximately twice that ofa pipeline with wall thickness similar to each one of the two shells.The lay rate will be around 2/3 of a normal lay rate mainly due to more workat each field joint.
The pipe-in-pipe solution will only be used at the portion of the pipelinewhere the water depth require this solution (e.g. deeper than 1000 m)
The inner diameter of this solution can be kept constant
Engn. + + Constr.
Cost ofOffshorePipelines
PIP
Steel pipe $ 1250 /m
$ 1875 /mMaterial
Material
Engn. + + Constr.
New solutions 2:Subsea pipe splitting
Two parallel pipes with reduced diameter is already used in the Black SeaBlue Stream project with onshore splitting.Subsea splitting require either
– That all pigging can be avoided or– Manifold that allow for RFO and regular pigging
Pigable manifolds are available, but developmentwork is needed to qualify for the actual dimensions
New solutions 3 :Reduced diameter on limited part of pipeline
If the extremely deep section has limited length, hydraulic loss in thissection can be accepted.Multi-diameter pigging technology is capable to take a 30% diameterreduction. (28” to 42” pig is developed for Åsgard Transport)To achieve the required benefit of this solution a 50% diameter reduction isneeded. Preliminar investigations show that this is possible, butdevelopment work is needed.
New solutions 4
Deep water S-layingAllowance for increased strain over stinger will provide a steeper departureangle and reduced tension requirement to S-lay vesselLower shear stiffness in P-I-P annulus reduces the strain in outer shellLower submerged weight leads to lower tension requirement
Qualification of deep water S-laying will increase the availability of lay vessels and reduce laying costs
Technological challenges:Contact forces on stingerFracture capacity due to bending on stinger and sag bendSeabed stability during installation
– Reduce horisontal laying radius
ConclusionsFor ultra deep water pipeline transport, the combination of pipediameter and water depth indicates the project challengeBUT:The capability to install and operate such pipelines will also requirecontrol of :
• DESIGN FRAMEWORK• GEOHAZARD ASSESSMENT• DEEP WATER LAYING• MAPPING• FREE SPANS• SEABED INTERVENTION• HOT TAP AND REPAIR TECHNOLOGY• RISK MANAGEMENT & PROJECT ORGANISATION
• New technology is under development to be capable of ultra deepwater installation and diverless hot-tap and repair of existingpipeline systems