The Nansen production platform operates in about
3,500 feet of water off the Texas coast.
Devon owns 50 per cent working interest in the
facility.
Thanks to new technology and recently developed materials, deepwater oil and gas reserves that
were considered inaccessible as little as ten years ago are being opened up for exploitation.
Stainless Steel World explores this new frontier, and the role duplex stainless steels are playing
in deepwater development.
By James Chater
Pushing back the frontier
The higher the oil price climbs (it is
hovering around USD 67 as I write),
the more development of oil and
gas reserves marooned in deepwater
far from the coast makes economic
sense. Oil is currently being extracted 8,000 feet below sea level, at a
depths of up to 29,000 beneath the
seabed, equivalent to the height of
Mount Everest. But the industry is
preparing to dig deeper: to 10,000
feet below sea level, then to 15,000
feet, the deepest threshold in the
Gulf of Mexico.
Such developments bring a host of
technical unknowns, and already
the sea floor is being invaded by
technology and machinery that
www.stainless-steel-world.net
resembles something out of science
fiction. Pressures of 15,000 psi or
more are too much for human beings to bear, so instead remotely
operated vehicles (ROVs) resembling
spiders or crabs scuttle, creep and
crawl along the surface to carry out
trenching, installation and repair
services. The pumps and valves that
transport the oil to the surface are
also operated remotely.
"Hub-and-spoke" technology,
whereby several wells are tied back
to one central hub, is making
certain remote fields viable for the
first time. These fields can be
operated remotely using the latest
in fibre optic and automation
technology.
S T A I N L E S S
GoM leads the way
With each new project, new records
are broken, and this is particularly
true of the Gulf of Mexico, with its
privileged location near the world's
oil capital, Houston. Independence
Hub, which will go on-stream this
autumn, will contain the world's
deepest subsea production tree,
flowline installation, SCRs, export
pipeline and subsea umbilical order.
The umbilicals will require 1,000
miles of stainless steel tubing. Shell's
Perdido project will go even deeper,
to 10,000 feet, and will have the
world's deepest spar production facility. Brazil's national oil company
Petrobras is building on its consider
able deepwater experience
S T E E L
W O R L D
J U N E
2 0 0 7
47
DUPLEX
Mount Everest in the sea:
how duplex stainless steels are
transforming the offshore
industry
Duplex
GoM Discoveries
Recent gulf of mexico oil and gas dicoveries
(in South America, the GoM, West
Africa and Asia) to develop two subsea wells in the Cascade field and
one in the Chinook field in the Gulf
of Mexico. A number of new
technologies will be used to develop
these wells, which are located 8,200
feet below the sea and are drilled to
27,000 feet. These include a disconnectable turret buoy allowing a
FPSO to move offsite during severe
weather; crude transportation via
shuttle tanker; free-standing hybrid
risers; subsea electric submersible
pumps; torpedo pile vertical-loaded
anchors; and polyester mooring systems. First oil is expected to flow in
2009. In the light of these and similar projects (for instance Chevron's
Jack 2) it is predicted that the deepwater area of the Gulf of Mexico
will arrest the recent decline in US
oil production. The US government
is also authorizing exploration and
development in areas that were previously out of bounds: on 30 April
2007 it announced it will sell leases
for drilling on the Outer
Continental Shelf and off Alaska,
a move expected to produce 10 billion barrels of oil and 45 trillion cubic feet of gas. Elsewhere in the
Americas, deepwater activities are
dominated by Petrobras. In
September 2006 Petrobras Energía,
Argentina-based Energía Argentina
(Enarsa), and Spain-based Repsol
YPF formed a consortium to develop
oil and gas on Argentina's
deepwater continental shelf. The
consortium plans to carry out exploration in 200-3000 metres of water
www.stainless-steel-world.net
about 250 kilometres off the coast.
Among the companies that have
won contracts in projects operated
by Petrobras are Aker Kvaerner,
INTEC Engineering and Technip.
Africa and Asia
Offshore Africa is another region in
which Petrobras, along with the US
and UK oil giants and other oil
companies the world over, are intensely interested. It was estimated
this region accounted for 6.3 per
cent of the world total oil production in September 2006. Nigeria occupies the top spot, but is likely to
be supplanted by Angola, especially
if the current security risks in
Nigeria continue. BP, Shell, Total,
India's Marathon, China's Sinopec
and CNOOC, South Korea's KNOC
and Australia's Woodside are among
the companies exploring and operating off the coast of West Africa.
Deepwater exploration and development is also picking up in Asia.
Among the first countries in the region to venture into deepwater,
India has experienced a high level
of exploration and production activity over the past five years, a trend
that will continue. For the country's
first major deepwater project, KGD6 in the Krishna-Godivari basin off
the east coast, Aker Kvaerner is delivering a complete subsea production system to be installed on the
sharply sloping seabed, at water
depths of 2,297-5,577 feet. A second
field (400-2,700 metres deep), located offshore Kakinada, halfway up
India's east coast, also shows
S T A I N L E S S
Spar for Shell’s Perdido project. Moored in about 8,000
feet under water, the Perdido regional DVA (direct vertical access) spar will be the deepest spar production facility in the world. First production from Perdido project
is expected around 20110
promise: in November 2006 DNV
announced it had been asked to
undertake a feasibility study of the
field. Malaysia is another country
offering substantial deepwater opportunities, and its hydrocarbons
national Petronas, which has interests in India, Indonesia, Thailand
and Vietnam in addition to its own
backyard, has ambitions to transform the country into a regional oil
and gas hub. The country has 5.25
billion barrels of oil reserves and
87.95 trillion cubic ft of gas reserves;
S T E E L
W O R L D
J U N E
2 0 0 7
49
Petronas has estimated that 65 per
cent of undiscovered oil and 43 per
cent of undiscovered gas will come
from deepwater (1,000ft or deeper).
The region has produced some notable firsts: for instance the Kikeh
development, which will begin production in the second half of 2007,
will be the first outside the GoM to
use a spar as a production system.
In China, Canada's Husky Energy
announced in June 2006 what it
claims to be the first deepwater discovery, in the Pearl River Mouth
Basin.
The future
3D geological modelling is uncovering hitherto unknown reserves,
while new technology is making
them recoverable for the first time.
Deepwater oil and gas is therefore
destined to form an ever larger part
of the hydrocarbon mix. Much of
this will come from some of the
world's most hostile and ecologically fragile regions, such as the
Shtockman field in the Arctic to the
50
S T A I N L E S S
S T E E L
W O R L D
Beaufort Sea offshore Alaska. But the
challenges are not only technical
but also political: slap in the middle
of the South China Sea lie the
Spratly Islands, which could contain
up to 105 billion barrels of oil, and
the sovereignty of which is disputed
by six countries in the region. The
potential for conflict gives rise to
concern, but the potential for oil
and gas riches is also enormous.
Materials requirements
In deepwater installations, materials
are expected to perform under higher pressures (15,000psi) and to withstand higher temperatures (300
Fahrenheit) than ever before. In
Arctic regions, ice scour affects the
design of wellheads, trees, flowlines,
umbilicals and pipelines. Export
pipes, only 10 miles long and 12
inches in diameter until a few years
ago, can be expected to exceed 300
miles, with diameters of 48 inches
and running 1,000 feet deep.
Hurricanes, sea currents and rugged
terrain on the seabed are also fac-
J U N E
2 0 0 7
tors. Risers are will have to be built
more robustly to withstand high
pressure and fatigue due to vortexinduced vibration and wave impact.
To overcome these problems stainless steels, especially duplex and super duplex, are becoming increasingly indispensable. According to
the tubing and umbilical manufacturer Aker Kvaerner, super duplex
stainless steel is recommended for
any field development that exceeds
10 years of productive life. The steel
tube umbilical has to be tailor-made
for each subsea development, as lifetime of the well, wellstream characteristics, chemical injection requirements and pressure rating, all of
which vary with each project, are
critical to the proper material selection. Sandvik was among the first
companies to develop duplex grades
for the umbilicals used in today's remote deepwater fields, providing
the ultra-high strength and corrosion resistance needed for wellhead
control systems in enhanced oil and
gas recovery systems.
www.stainless-steel-world.net
Duplex
Statoil’s Kvitebjørn platform in the North Sea. A pressure of 780 bar prevails in the
Kvitebjørn reservoir, 4,000 metres beneath seabed. The temperature is 150 °C.
Photo copyright © Statiol.
With its super duplex SAF 2906 and
hyperduplex 3207 HD grades,
Sandvik has extended the corrosion
resistance and high strength of its
super duplex grade SAF 2507 (see
table).
Outokumpu has also successfully introduced duplex grades for subsea
service. When Petro-Canada experienced problems with saltwater corrosion in its field 100 miles off the
coast of Newfoundland, Canada, the
Finnish manufacturer was able to
provide two grades of duplex pipe
with saltwater corrosion-resisting
properties and high strength:
Duplex 2205 Code Plus Two® and
Super Duplex 2507. Outokumpu has
also developed lean duplex grade
LDX 2101, which is more corrosionresistant than 304, has double the
wield strength and can deliver substantial savings in both cost and
weight. LDX 2101 also has good
weldability, another advantage in
the construction of flexible pipeline
and umbilical tubing in offshore
projects. Technip ordered this material for Total's Dalia deepwater project off Angola, and RathGibson is
Material
Tensile strenght
Max.
temp.
Comments
SAF 2906
860-1160Mpa, slightly
higher than SAF 2507
60C
Higher Cr and N content than SAF
2507. Moderate amount of Mo.
Corrosion properties similar to saf
2507
3207 HD
980-1180 Mpa
90C
Described as a “hyper duplex”
grade. Localised corrosion resistance exeeding all superduplex alloys.
using it in the construction of its
zinc-coated umbilical tubes.
Similar to LDX 2101 is Allegheny
Technologies' 2003™ lean duplex
stainless, introduced in 2006 as a
cheaper alternative to the highnickel alloy 316L in both subsea and
topside applications. It is also considered ideal for the high-pressure
demands of offshore piping systems
that transport sweet to moderately
sour oil and gas, and the alloy has
been successfully applied in deepwater flowlines. Allegheny supplied
Wellstream International Ltd with
1.2 million pounds of AL 2003™ for
the flexible pipe used in the Kikeh
Field Development Project offshore
Malaysia. This alloy, along with its
duplex 2205 and super-austenitic
AL6XN® alloys, gained NORSOK
(Norwegian oil and gas industry)
approval in 2006.
Table: Properties of Sandvik duplex grades (see www.smt.sandvik.com)
www.stainless-steel-world.net
S T A I N L E S S
S T E E L
W O R L D
J U N E
2 0 0 7
51
Duplex
Some recent deepwater project announcements
Date
Dexciption
Depth
Approval for Shenzi oil and gas field, GoM. First oil is
4,300ft
Operator/Other owners Contractors
AMERICAS
6/2006
expected by mid-year 2009
BHP Billiton/ BP,
INTEC Engineering
Hess
(subsea work); Technip
(flowlines, SCRs)
9/2006
Decision to explore Argentina's deepwater continental shelf
200–3,000m
Petrobras/Enarsa,
9/2006
Jack 2 well in GoM drilled (see box). Commercial production in 2008
7,000ft; drilled to
Chevron/Devon
depth of 28,000ft
Energy, Statoil
8,000ft
Shell/Chevron, BP
700m, 2,000m,
Petrobras
Repsol
10/2006
Perdido Regional Host Project (Great White, Tobago and Silvertip
fields; see box). First oil expected around 2010
10/2006
(subsea systems)
3 riser systems, 2 for offshore Brazil
Aker Kvaerner (awarded
2,400m
1/2006
Technip (umbilicals); FMC
10 pipelines, 6 risers, 25 jumpers; installation of 5 umbilicals and 4
by Queiroz Galvão
1600–2000m
Shell
Subsea 7
Approval of plan for Cascade and Chinook oilfields, GoM: 3 wells tied
8,200ft; drilled to
Petrobras/Devon
back to FPSO. Production to start in 2009 (see box)
depth of 27,000ft
Energy
12/2006
Subsea flowline and risers for Bass Lite field, GoM
6750ft
Mariner Energy
Technip
1/2007
Pre-FEED for subsea work on Gotcha field, GoM
7,250–8,100ft
Total/Nexen
INTEC Engineering
2/2007
Subsea engineering services for Blind Faith field
7,000ft
Chevron
INTEC Engineering
3/2007
142km of flexible pipes for Roncador field, offshore Brazil
1,740m
Petrobras
Technip
3/2007
Flowlines and the risers for Ursa and Princess fields, GoM
3,780ft
Shell
Technip
4/2007
Flowlines for Canapu field, offshore Brazil
1,608m
Petrobras
INTEC Engineering
4/2007
22 subsea christmas trees, control systems, etc. for Brazil’s Plangas
Petrobras
Cameron
Petrobras
Aker Kvaerner
manifolds for BC10 fields offshore Brazil
12/2006
gas plan
4/2007
18 subsea christmas trees
AFRICA
6/2006
Subsea trees for offshore West Africa
Aker Kvaerner
6/2006
Deepwater SURF installation project offshore Angola. Installation in
Acergy
2008
2/2007
2 deepwater discoveries announced on Block 32, 175 miles offshore
1977m
Total/Marathon,
Angola
Sonangol, Esso,
Petrogal
4/2007
Deepwater discovery announced in Miranda field on Block 31, 165km
2436m
Marathon
offshore Angola
Production, Angola,
Sonangol, Esso,
Statoil, TEPA
ASIA
6/2006
Drilling facilities for ultra-deepwater semisubmersible in S. Korea.
Daewoo
Aker Kvaerner
Scheduled for delivery in 2009
6/2006
China’s first deepwater find announced, the Liwan 3-1-1 gas well in
1500m
Husky
the Pearl River Mouth Basin, 250km offshore from Hong Kong
9/2006
Ultra-deepwater semisubmersible rig, “ENSCO 8502”
ENSCO International
Keppel FELS
10/2006
Contract for drilling facilities on an ultra deepwater semisubmersible
Daewoo
Aker Kvaerner
rig.
11/2006
Verification of deepwater field offshore Kakinada, India
400–2,700m
1/2007
Subsea production system for India
1100–1400m
1/2007
Deepwater semisubmersible
3000m
DNV
Aker Kvaerner
PetroRig III (sub-
Jurong Shipyard
sidiary of
PetroMena)
4/2007
Subsea production system for KG-D6 deepwater development in the
2,297–5,577 feet
Aker Kvaerner
Krishna-Godivari basin off India’s east coast. Delivery at end of 2007
AUSTRALASIA
8/2006
Exploration of Exmouth Plateau, offshore W. Australia
Chevron/Shell
Looking for projects and tenders? Why not subscribe to KCI’s Projects and Tenders newsletter? Visit www.projectsandtenders.com or ring Erica Riethorst,
[email protected], tel. +31 575 585271.
www.stainless-steel-world.net
S T A I N L E S S
S T E E L
W O R L D
J U N E
2 0 0 7
53