“prediction is very difficult, especially about the future”

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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”. - PowerPoint PPT Presentation

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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)

“Prediction is very difficult, especially about the future”

Niels Bohr(1885 – 1962)

Nobel Prize in Physics 1922

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”

“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”

Vannevar Bush (1945)

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 operatorswish to make ‘safe’ choices ability to pass costs on to someone elsefear of being punished if something goes wrongfear of being the first to do anythinghigh costs of innovationhigh costs of research and development

and those reasons operate at all levels

a lot can be done:

improved design methods better understandingmore use of software

alternative materials composites

alternative welding systems eliminate manual and conventional automatic welding

cheaper combinations of example: laying liquid-filleddesign and construction

improved design methods better understandingmore 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

pipeline

PSU

pressure

Widely used for boiler tubing, chains, railsUsed in USSR in 1950’s for 30,000 km 114 to 1520 mm pipeWelding equipment fitted inside large-diameter pipesdeveloped in USA by McDermott - presently decommissioned

weld completedIn 3 minutes

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 treatmentbitter 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

Coating of epoxylubricant and secondary seal

Buffer ring to protect internalcoating/lining from damage

Conventional30o bevel ends

Hydraulic squeeze

• Pipe is pressed into the connector and yields. • Connector wall thickness sufficient for connector to remain in elastic region.

Serrated surface

Internallycoated/linedpipe

CONNECTOR

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”

pig

wat

er-f

illed

air-

fille

d

J-lay bargesupport vessel

flex

ible

hos

e

start-up head

h

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 20 inch (508 mm)maximum operating pressure 30 MPa gauge

(maximum external – minimum external)

steel grade X70 (SMYS 485 MPa, SMTS 605 MPa, and obeying supplementary

requirement U)out-of-roundness 0.01 (DNV definition)elastic modulus 210000 MPaPoisson’s ratio 0.3steel density 7850 kg/m3anti-corrosion coating 3 mm pp,

density 1200 kg/m3 water density 1025 kg/m3

0

5

10

15

20

25

30

0 500 1000 1500 2000 2500 3000

height from seabed to top of water fill (m)

wal

l th

ickn

ess

(mm

)

strategy 1

strategy 2

0

1

2

3

0 500 1000 1500 2000 2500 3000

height from seabed to top of water fill (m)

sub

me

rge

d w

eig

ht

(kN

/m)

water-filledempty

0

200

400

600

800

0 500 1000 1500 2000 2500 3000

height from seabed to top of water fill (m)

tens

ion

at s

urfa

ce (t

onne

sf)

pig

wat

er-f

illed

air-

fille

d

J-lay bargesupport vessel

flex

ible

hos

e

start-up head

h

‘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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