APslides_FINAL

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Moving forward further in the next 20 years
than in the past 20 years: the vanishing era
of the 10 per cent change
Andrew Palmer
(National University of Singapore)
Niels Bohr
(1885 – 1962)
Nobel Prize
in Physics 1922
“Prediction is very difficult,
especially about the future”
Lord Kelvin (1890)
“I have not the smallest molecule of
faith in aerial navigation other than
ballooning, or of expectation of good
results from any of the trials we hear of,
so you will understand that I would not
care to be a member of the Aeronautical
Society”
Vannevar Bush (1945)
“There has been a great deal said
about a 3000-mile high angle rocket
shot from one continent to another,
carrying an atomic bomb…
I say, technically, I don’t think anyone in
the world knows how to do such a
thing, and I feel confident that it will not
be done for a very long time to come. ..I
wish the American people would leave
that out of their thinking”
go back almost 70 years….
requirement in 1944
supply gasoline to the army that will invade the continent of Europe
(keeping in mind that the ports will have been destroyed)
construct small-diameter pipelines from England to France (100 km)
in one night (because of the possibility of attack from the air)
go back almost 70 years….
requirement in 1944
supply gasoline to the army that will invade the continent of Europe
(keeping in mind that the ports will have been destroyed)
construct small-diameter pipelines from England to France (110 km)
in one night (because of the possibility of attack from the air)
Anglo-Iranian ideas
HAIS: pipe made of lead, like a submarine cable with no core, made
on cable-making machinery
HAMEL: steel pipe, wound onto floating reels
HAIS
HAMEL
HAMEL
we cannot lay 110 km of pipeline in one night now in 2012
(is that because we know so much more about it ?)
“It was a fantastic concept, and in many ways it was a miracle it
worked as well as it did – because we had chaps like me who really
knew nothing about pipelines before we started’ (M. Lickens)
that project ought to be an inspiration to us in marine pipelines (and
in other technologies too)
in the late 1970s maximum lay rates were about 4 km/day, though
average rates were much lower
in 2012 maximum lay rates are about 6 km/day, and average lay
rates are much higher than they were
the conservatism and slow progress of the industry are deeply
discouraging
progress is horribly slow by comparison with other industries
(computers, consumer electronics, medicine, surgery, defence)
but there are understandable reasons for them:
conservatism of operators
wish to make ‘safe’ choices
ability to pass costs on to someone else
fear of being punished if something goes wrong
fear of being the first to do anything
high costs of innovation
high costs of research and development
and those reasons operate at all levels
a lot can be done:
improved design methods
better understanding
more use of software
alternative materials
composites
alternative welding systems
eliminate manual and
conventional automatic welding
cheaper combinations of
design and construction
example: laying liquid-filled
improved design methods
better understanding
more use of software
all the calculations are straightforward, and can be carried out and
documented by user-friendly programs
programs incorporate necessary data (pipe specifications, coating
data, corrosion data….)
design process can be made automatic and immediate
many alternative welding techniques exist
friction
laser
flash-butt
homopolar
friction stir
but why do we have to weld the pipe anyway ?
threaded connections (like drill-pipe)
interference fit connectors
Friction Stir Welding (FSW)
metals are “stirred” by a rotating tool
metal is not melted, but rather softened, stirred, and forged together
benefits: Elimination of solidification defects, low heat input, improved
weld properties over arc welding, no filler material, and zero fumes
Flash Butt Welding
PSU
weld completed
In 3 minutes
pressure
pipeline
Widely used for boiler tubing, chains, rails
Used in USSR in 1950’s for 30,000 km 114 to 1520 mm pipe
Welding equipment fitted inside large-diameter pipes
developed in USA by McDermott - presently decommissioned
Flash butt welding of railway track
flash butt welding (FBW)
has failed to take off for pipelines in West (but widely used for rails and in
manufacturing)
“not invented here”
“Russian connection”
some concerns about need for heat treatment
bitter opposition of welders’ labour unions
a recent Russian book (‘Svarka truboprovodov’, Mustafin, F.M.) says that ‘..at
the present time, [FBW] is not applied to pipeline construction’
the reasons for that are not known
weldless options
•
•
•
Screwed connections
Interference fit connections
Memory metal
–
–
–
–
–
Fast
Single connection location
J-lay option
Non-weldable materials
Internally coated pipe
Interference Fit Connections
Hydraulic squeeze
CONNECTOR
Conventional
30o bevel ends
Internally
coated/lined
pipe
Coating of epoxy
lubricant and
secondary seal Serrated surface
Buffer ring to protect internal
coating/lining from damage
• Pipe is pressed into the connector and yields.
• Connector wall thickness sufficient for connector
to remain in elastic region.
Screwed Connectors
•
•
•
•
•
•
Same technology as used for production (downhole) tubing using
premium connectors
Installed from drilling rig
Suitable for non-weldable materials
Internally coated/lined materials
J-lay installation
Economic for small diameter pipes
cheaper combinations of design and construction
must a pipeline laid in deepwater be designed to resist the
external pressure?
conventional practice is that the pipeline is air-filled during
laying
that drives up the wall thickness
why not fill the pipe with water so that the internal pressure
balances the external pressure?
“because it is too heavy if it is liquid-filled”
support
vessel
J-lay barge
pig
h
start-up head
compare two design strategies for 3000 m depth
• strategy 1: conventional, lay air-filled, design to resist
external pressure
• strategy 2: lay partly liquid-filled, design to resist operating
pressure
(design intentionally limited to these two conditions)
DNV collapse formula
diameter
maximum operating pressure
steel grade
out-of-roundness
elastic modulus
Poisson’s ratio
steel density
anti-corrosion coating
water density
20 inch (508 mm)
30 MPa gauge
(maximum external –
minimum external)
X70 (SMYS 485 MPa,
SMTS 605 MPa, and
obeying supplementary
requirement U)
0.01 (DNV definition)
210000 MPa
0.3
7850 kg/m3
3 mm pp,
density 1200 kg/m3
1025 kg/m3
wall thickness (mm)
30
25
20
strategy 1
15
strategy 2
10
5
0
0
500
1000 1500 2000
2500 3000
height from seabed to top of w ater fill
(m )
submerged weight (kN/m)
3
2
waterfilled
empty
1
0
0
500
1000
1500
2000
2500
height from seabed to top of w ater fill (m )
3000
tension at surface (tonnesf)
800
600
400
200
0
0
500 1000 1500 2000 2500 3000
height from seabed to top of w ater fill (m )
support
vessel
J-lay barge
pig
h
start-up head
‘The driver for change is creative dissatisfaction with things as they are’
costs can be reduced and construction speeded up, without
compromising safety and efficiency (and if necessary within the
framework of existing codes)
there is much more to be done!
Thank you for your attention
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