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High Productivity Pipeline
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IST Lisbon 29/04/2013
HIGH PRODUCTIVITY PIPE GIRTH WELDING
DEVELOPMENTS IN MECHANIZED
WELDING OF PIPELINES
David Yapp
1
2
Natural Gas Pipelines in Portugal
Portugal
pipelines
0.7 m diameter,
1000 km
3
Sines LNG (Liquid natural gas terminal)
Natural gas
storage
and
gasification
plant
4
Increases in oil and gas consumption
• Oil and natural gas consumption continues to grow due
to increased industrialisation in developing world
• Natural gas consumption also grows due increased
use in high efficiency combined cycle electricity
generating
• Many reserves are in remote regions – long pipelines
required for transportation
• Strong incentive for development of high productivity
welding processes to reduce costs
• Higher strength steels reduce linepipe costs by
reducing pipe wall thickness, and hence steel tonnage
5
Recent Developments in High Productivity Pipeline Welding
• Arc welding developments, including tandem GMAW are currently providing substantial increases in productivity
• “One-shot” and forge welding processes have seen major developments – but little application so far
• Laser welding has promise for the future, but:
• High productivity must be achieved while still achieving satisfactory weld properties, with inspectable, high quality welds and low repair rates
6
Manual Arc Welding
• Open Vee
Groove
• Large weld
metal
volume
• Slow
Mechanised fill pass welding
• An external
welding head or
“bug”, is used for
fill pass welding,
welding
downwards
• Welding takes
place in a narrow
groove, only 5 mm
wide, with one
pass above
another, 5G
position
7
Mechanised narrow groove GMA welding
Mechanised GMA welding was introduced by CRC
Evans in the 1960’s. Use of a narrow groove reduces
weld volume and increases productivity
8
9
Pipeline installation
• Arc welding is
almost always used
for pipe welding,
onshore and
offshore
• The rate at which
each 12 m pipe
length can be
added depends on
how fast the root
run and first/hot
pass are
completed.
• “Fill stations” keep
up with pipeline
advance – typically
one or two for each
welding pass
Pipe root welding – Internal Copper Backing
Pipe roots can
be made
using an
external
welding bug,
with a clamp
incorporating
a copper
backing ring
inside the pipe
10
Pipe root welding – no backing
Recent developments in
controlled deposition GMA
processes, such as Lincoln
STT and Fronius CMT, have
enabled high quality roots
without backing. This slide
shows a root weld in a 13%Cr
pipe made at 0.8 m/min using
an external bug and closed
root with the Lincoln RapidArc
process in 2G position.
11
Pipe root – Internal Welding Machine
The root run can also be made using from inside the pipe
using an internal welding machine (IWM) integrated with a
pipe clamp, with 3 or 4 welding torches operating
simultaneously
12
Dual torch pipe welding
• Dual torch welding was introduced in the 1990’s – two torches
are mounted on one welding bug to double weld deposition rate
13
Pipe welding offshore
12 m pipe lengths
are loaded on to a
lay barge, and as
pipe is welded the
large can move
forward as the pipe
enters the sea from
a “stinger” at the
rear of the barge.
This is called “S”
lay, since the pipe
makes and S shape
from the barge to
the sea bed
14
Pipe welding Offshore
Construction of the
Nord Stream Pipeline
started in the
Swedish Exclusive
Economic Zone of
the Baltic Sea in
early April 2010. The
pipelay vessel
Castoro Sei began
offshore pipe laying
near the Island of
Gotland and with a
distance of 675
kilometres from the
pipeline’s starting
point near Vyborg,
Russia
15
Double Jointing
• Pipe is typically supplied in 12 m lengths, both for
manufacturing and for transport reasons
• “Double jointing” means girth welding two lengths of
pipe together by rotating the pipe under the welding
torch, (1G welding position) typically using SAW
(submerged arc welding), and usually in the field or on
a laybarge
• Substantial gains in pipe lay rate are possible, e.g.
doubling the lay rate on a laybarge
16
SAW Double jointing
• SAW welding from
inside and outside
pipe
• High deposition rate,
robust process
17
Topic 2 Double joint pipe welding
SAW Double Joint Welding Double joint
submerged arc
welding on board
Castoro Sei,
installing
Nordstream
pipeline
18
Pipe Welding Offshore
Two bugs welding simultaneously
on board the Castoro Sei 19
Pipe girth welding on lay barge
Since the pipe
is moving
along the deck
of the barge, a
welding frame
or rack can
used, with four
or more
welding
torches
operating
simultaneously
20
Deep water pipelay
In deep water,
the pipe could
buckle as it
leaves the
stinger, due to
the weight of
pipe in the water.
In this case, the
pipe is vertical in
a tower, but at
most only two
welding stations
are possible.
This is known as
“J” lay 21
Reel Lay
For reel lay the pipe
is welded on land,
then wound onto a
large reel or spool.
The reel lay ship can
then lay the pipe
rapidly. Maximum
pipe diameter for this
technique is about
400 mm . The pipe
(and welds) must be
able to withstand the
plastic deformation
from reeling and
unreeling 22
Pipe welding for reel lay
• The pipe is welded in a spool base, to make “stalks”, up to 0.5
km long, which are welded together as they are loaded onto the
reel
23
Continuous reel lay
• Schematic of Heereama’s deep water construction vessel Aegir set
up for continuous reel lay operation. 24
25
Tandem Arc Welding
• Tandem welding developed in
1990’s
• Two wires in one torch, feeding
into one weld pool
• Enables welding at much higher
speed, doubles deposition rate
• Pulsed welding – pulses
synchronized to prevent magnetic
arc interaction
Time (ms)
Cu
rren
t (A
)
26
Narrow Groove Tandem Pipe Welding
• First implemented at Cranfield University in 1997
• Specially developed torch for narrow groove welding
• Successful procedures developed: welding speed 40 to 60 inches / min
• Weld geometry equivalent to conventional single wire weld
• Fill pass welding productivity governs number
of welding station and equipment required to
keep pace with root welding
• Increased fill pass productivity can lead to
substantial reductions in equipment and people
costs
• High motivation to increase fill pass
productivity, especially for long, large diameter
pipelines
2 welding bugs – 4 GMAW tandem torches
8 wire feed units
8 synchronised pulsed GMAW power sources
The CAPS System
27
Dual tandem welding – CAPS Cranfield Automated Pipe-welding System
• 2 welding bugs,
each with two
torches, each torch
with two wires = 8
wires welding
simultaneously
• 4 times increase in
productivity
compared to single
torch welding
Dual tandem CAPS trials
28
Dual torch tandem welding in the field Godin Lake, Canada, 2004
16 fill pass
stations required
for single torch
single wire
welding can be
reduced to four –
hence large
reductions in
equipment and
personnel
“The welding crew moved on to the Grade 690 in the afternoon of Saturday, 31st January 2004. Mechanized welding refamiliarization and three production welds were completed. The first full day of welding was Monday, 2nd of February when 25 welds were inspected without repair. In my recollection, this is the first mechanized welding kick off (never mind one with new welding technologies) with no repairs in the first day of welding. The number of welds completed by Friday was 174 and there were a total of seven repairs for lack-of-sidewall fusion in mechanized GMAW passes and a final repair rate of five percent” David Dorling, TCPL
29
Pipe weld macros
Dual torch
(single wire)
weld –
double
productivity
Dual torch
tandem wire
weld – 4
times
productivity
Single torch
tandem wire
weld –
double
productivity
Single torch
weld –
widely used
30
31
Tie-in welding for high strength linepipe
• Narrow groove welding is possible for mainline pipe welding. However, the required accurate fit-up cannot be achieved for tie-ins – connection of the main line at river and road crossings, connections to other equipment, and in hilly terrain. In this case, an API 60º Vee prep is used, often with rutile flux-cored wire.
• For X100 pipe initial work on API 60º bevel angle, and rutile flux cored wire failed to meet yield strength overmatching requirement, and stronger rutile wire was not available
Basic flux-cored tie-in welding
• New concept - weld vertically down with basic wire and reduced Vee preparation, 30º included compared to API 60º included •Pulsed FCAW vertical down, Philips PZ6149 basic wire, Ar5CO23O2 , 0.9 kJ/mm •Yield strength 844 MPa – met overmatching •Charpy toughness similar, both 50J at - 60ºC,
32
Welding of High Strength Steels
High Strength Linepipe – X80 and X100
• X80 has now been used on a significant basis, with
extensive use in the UK
• X100 has so far only been used for short trial pipelines
• Substantial development programme completed at
Cranfield University, with extensive testing - 100 trial weld
procedures, 40 full procedure welds
• Procedure Acceptance Tests based on API 1104
• Several heats of X100 plate and pipe
• Detailed evaluation of commercial and experimental
consumables
• Procedures qualified for all process variants, with
recommended commercial filler wires
33
Welding of High Strength Steels
Dual tandem weld metal yield strength for different filler wires
500 600 700 800 900 1000 1100
1
2
3
4
5
6
Fil
ler
Wir
e
Rp0.2 (MPa)
Oerlikon Carbofil NiMo1
Bohler X70-IG
Oerlikon Carbofil 120
Thyssen X85-IG
Bohler X90-IG
Thyssen X85-IG/Oerlikon Carbofil NiMo-1
6=2.2Ni0.6Mo0.4Cr ; 5=1.8Ni0.5Mo0.3Cr ; 4=2.2Ni0.55Mo0.3Cr
3=1.8Ni0.5Mo0.3Cr/1.0Ni0.3Mo ; 2=1.3Ni0.25Mo0.25Cr ; 1=1.0Ni0.3Mo
Commercial filler wires are available to achieve the weld metal strength
level required. Note however, that higher strength is usually achieved
compared to the classification (e.g. AWS) due to the much faster cooling
rates in narrow groove welding compared to electrode classification test 34
Welding of High Strength Steels
Weld metal Charpy toughness for different processes in 5G X100 pipe girth welds
020406080
100120140160180200220240260280
-90 -80 -70 -60 -50 -40 -30 -20 -10
Temperature ( 0
)
Ab
sorb
ed E
ner
gy
(J)
Average Single Tandem(36 in x 19mm;1.0Ni0.3Mo), (WM)
Average Dual Tandem(Medium Carbon;52 in x 22.9mm;1.8Ni0.5Mo0.3Cr/1.0Ni0.3Mo),(WM)
Single Wire (36 in x 14.9mm;1.0Ni0.3Mo), (WM)
Dual Torch(30 in x 19mm;1.3Ni0.25Mo0.25Cr),(WM)
Dual Torch(36 in x 19mm;1.0Ni0.4Mo),(WM)
Welding with appropriate argon/CO2 mixtures, combined with fine grain
structures due to fast cooling, generally produces excellent low
temperature weld metal toughness
35
Welding of High Strength Steels
Process Variation Cooling Curves Cooling curves for narrow gap PGMAW pipewelding process variants - internally placed
(layer base) thermocouple in contact with initially molten weldpool at approximate pipe
mid thickness (36" OD x 19.05mm WT)
0
200
400
600
800
1000
1200
1400
1600
1800
0 10 20 30 40 50 60 70 80 90 100
Time (s)
Tem
pera
ture (
°C)
Single Wire Internal TC Tandem Wire Internal TC Dual Torch Internal TC Dual Tandem Torch Internal TC
Single wire and tandem welding (same heat input) have identical cooling
curves. Dual torch and dual tandem are slower in critical range due to
effect of second torch
36
Welding of High Strength Steels
Tensile Strength Variation Mechanised Narrow Gap Process Comparison of Weld Metal
Strength
750
800
850
900
950
1000
1050
Single Wire Tandem Wire Dual Torch Dual Tandem
Process Type
Str
eng
th (
MP
a)
Rp0.2 (MPa) Rm (MPa)
The effect of slower cooling for dual torch and dual tandem
is quite evident
37
Weld metal toughness vs oxygen content Single tandem, Ar/CO2 gas mixtures, Bohler Thyssen Union MoNi (0.1 C, 0.4 Mo, 1.1 Ni) Weld metal yield strength 750 -850 MPa (depends on oxygen content)
Effect of oxygen content on toughness
0
20
40
60
80
100
120
140 160 180 200 220 240 260
Weld metaloxygen content. ppm
Ch
arp
y im
pa
ct
tou
gh
ne
ss
J
- 20° C
- 40° C
- 60° C
- 80° C
38
•Initial Evaluation of New Welding Processes
•J-Lay welding
• Welding processes
• Bead Shape Characteristics
• Quality Assessment
• Productivity
Root Run Welding for 13%Cr steel pipes
39
Pipe Root Welding
CRA pipe root welding
• Very high root quality required for corrosion resistant
alloys (CRA) root welds - corrosion and fatigue
requirements
• TIG typically used for root – high quality but slow
• Productivity key issue – root welding key factor in
determining lay rate – and laybarge cost of 100’s of
thousand of dollars per day at sea
• Objective – develop processes to achieve high quality
with robust performance – but which process to
select?
40
ESAB
Lincoln
Fronius Kemppi
Migatronic
We need to achieve:
-Less Spatter
- Less Fume emission
- Lower Heat Inputs
- High Productivity
- High Stability
Others
Pipe Root Welding
Which welding process should we use?
41
Time [ms]
0 5 10 15 20
I [A
]
0
100
200
300
400
500
U [
V]
0
10
20
30
40
50Arc Current
Arc Voltage
Time [ms]
0 5 10 15 20
I [A
]
0
100
200
300
400
500
U [
V]
0
10
20
30
40
50Arc Current
Arc Voltage
Time [ms]
0 5 10 15 20
I [A
]
0
100
200
300
400
500
U [
V]
0
10
20
30
40
50Arc Current
Arc Voltage
Time [ms]
0 5 10 15 20
I [A
]
0
100
200
300
400
500
U [
V]
0
10
20
30
40
50Arc Current
Arc Voltage
Time [ms]
0 20 40 60 80
I [A
]
0
100
200
300
400
500
U [
V]
0
10
20
30
40
50Arc Current
Arc Voltage
Time [ms]
0 5 10 15 20
I [A
]
0
100
200
300
400
500
U [
V]
0
10
20
30
40
50Arc Current
Arc Voltage
GMAW-P RapidArc CMT-P
STT FastROOT CMT
Pipe Root Welding
Waveform designs – current and voltage
42
0
0.2
0.4
0.6
0.8
1
1.2
-20 -15 -10 -5 0 5 10 15 20Quality Index
Tra
vel S
peed [m
/min
]
STT Rapid Arc GMAW-P CMT CMT-P
Low Quality
Index
Moderate Quality
Index
High Quality
Index
Pipe Root Welding
Quality comparison between processes for CRA root
43
Main Conditions:
WFS = 8 m/min and TS = 0.50 m/min
2 15 4 20
CMT STT GMAW-P CMT-P Rapid Arc
-10
Pipe Root Welding
Quality comparison for CRA root welding
44
45
Process models
Development of Arc Weld Geometry Process Models
• Objective ; to develop a process model relating key process parameters to key weld quality features. Single weld bead in machined groove to allow precise measurement of bead geometry
• Parameters varied:
• Arc length
• Distance to sidewall
• Wire feed speed
• Travel speed
• Welding position
• Shielding gas
• Weld quality feature:
• Toe angle
• Undercut
• Max side penetration
• Side penetration at bottom of groove
• Bead penetration
46
Effect of Welding Position on bead shape
• Welding position round pipe has major effect on bead shape.
Other factors also affect bead shape. Convex or flat beads are
much more likely to generate defects on subsequent passes
12 o’clock 3 o’clock 6 o’clock
47
Process optimisation
• Essential to adopt a DOE (design of experiments) approach – frequent interactions occur between parameters. Central composite design selected – good for optimisation
• Mathematical equations for each quality feature:
• Series of 3-D response surface plots
• Software allows optimisation – select the best parameters to maximise groove side wall penetration and minimise corner angle
9.45
10.07
10.70
11.32
11.95
0.60
0.75
0.90
1.05
1.20
0.11
0.1875
0.265
0.3425
0.42
G
roo
ve
Sid
e P
en
etr
atio
n
A: WFS C: Wire Distance from Wall
48
Automated Pipe Welding
• Current mechanized pipe girth welding requires
welder to control torch cross seam position and
CTWD (contact tip to work distance) to high accuracy
for long periods in physically difficult positions
(standing on ladder, lying under pipe)
• High motivation to automatically control torch position
– requires sensors for torch/wire position relative to
weld preparation
• Two types of sensor systems investigated : through
the arc sensors, and laser stripe sensors
49
Through the arc sensors
• Thru-the-arc systems attractive: requires no extra sensors, measures position of arc, and does not require alignment of sensor and torch
• Difficult to implement for pulsed narrow groove welding: need to oscillate torch, and cannot get torch close to sidewall in narrow groove (groove width 5 mm, contact tip dia 3mm!), large variations in current and voltage from pulsing, additional interference from short circuits with short arc pulse welding
• New digital data processing algorithms developed – operate well in lab trials
Trials on tandem welding,
Lincoln 455 PS in constant
current mode
50
Control of cross seam position and CTWD
Torch height variation and voltage moving average
-6
-4
-2
0
2
4
6
0 1 2 3 4 5 6 7 8 9 10
Time (s)
To
rch
mo
vem
en
t (m
m)
0
2
4
6
8
10
12
14
16
18
20
22
24
Vo
ltag
e (
V)
Height
Voltage
σ = 0.14 mm
CTWD maintained at 2 mm
step in bead height
y = 0.5027x + 0.4054
R2 = 0.9772
σ: 0.14 mm
-1
-0.5
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
5.5
6
0 1 2 3 4 5 6 7 8 9 10
Time (s)
To
rch
mo
vem
en
t (m
m)
Good seam tracking with
deliberate misalignment of
torch / seam – 5 mm change
in 10 seconds
51
Laser stripe sensors
• Commercial laser stripe system – proven technology
• Seam following and CTWD straightforward – but registration must be maintained between torch and sensor
• Laser sensor can also be used to generate bead profile
Bead profile creation
The laser
generated weld
bead profile is
shown here
superimposed on
a macrograph of
the weld –
excellent accuracy
is achieved
52
Weld quality monitor
A series of
algorithms has
been developed to
judge weld quality
in real time. In this
case, the system
has detected that
the weld is
asymmetric, and
the orange
indicators show
that it is
unacceptable
53
Bead geometry 3-D Visualization
3-D visualization software –
shows bead profile from any
viewing angle. This figure
shows a series of cavities in
the weld bead.
The system can be used in
automated defect detection,
and bead geometry /
microstructure / modelling
54
55
Automation of Pipe Welding
• Current mechanized pipe girth welding requires welder to
control torch cross seam position and CTWD (contact tip to
work distance) to high accuracy for long periods in physically
difficult positions (standing on ladder, lying under pipe)
• High motivation to automatically control torch position –
requires sensors for torch/wire position relative to weld
preparation
• Two types of sensor systems investigated : through the arc
sensors, and laser stripe sensors
56
GMAW Pipe Arc Welding Conclusions
• Mechanised GMAW used extensively worldwide over last forty years
• Progressive, incremental improvements
• Developments • Root welding: Internal Welding Machine
• Root welding with copper backing ring
• Root welding without backing – new processes
• Narrow Groove Welding
• Dual torch welding
• Tandem Welding
• Dual Tandem welding (CAPS system)
• Seam following, automation and data acquisition
Forge welding processes Flash butt welding
• Heating provided by
arcing between pipe
ends, followed by
forging
• Developed at Paton
Institute and used in
former USSR
• Attempts to qualify for
use in West failed –
problems with HAZ
toughness, soft HAZ,
and inconsistency
57
Magnetically Impelled Arc Butt (MIAB) welding
• Similar to flash
butt welding –
but arc is rotated
at high speed
round pipe using
magnetic coils
• Prototype
system shown
here developed
by TWI for
TransCanada for
small diameter
thin wall tubes
58
MIAB welding “One-shot” or Forge Welding
• Typical weld joint
shown and
microstructure here
• Flash must be
removed after
welding
• Has same issues as
flash butt welding,
not used in practice
• Some recent
development in
Australia
59
Spinduction welding • Induction heating used to
heat pipe ends
• Rotation used to achieve
greater forging compared
to MIAB or flash butt
welding
• Currently under
development
60
61
Homopolar Welding • Resistance heating from Homopolar generator produces 2-3 second
high current pulse
• Recent development at University of Texas
• Most work on 75mm dia.pipe, some on 300mm pipe
• Very large investment in equipment needed for large diameter pipe
• No current development
Radial Friction Welding
• “Third body”
friction welding
process
• Internal mandrel
supports weld and
produced smooth
bore
62
Radial friction welding
Developed by
Stolt offshore
for welding
super duplex
stainless
steel, and
installed on
Seaway
Falcon – but
not used for
pipe laying
Equipment size increases dramatically as
pipe diameter increases
63
Friction Stir Welding
• Process developed by
TWI, with successful
applications on aluminium
• Developments in tool
material (PCBN) allow
welding of steel
• Portable equipment
developed for pipe welding
64
FRIEX welding • FRIEX is under active
development by Denys
NV, and has similarities
to radial friction
welding.
• Internal and external
flash must be removed
after welding
• Equipment has been
developed for pipes up
to 500 mm OD
• Relatively slow thermal
cycle, but reasonable
toughness has been
obtained by controlling
heat input 65
One-shot/forge welding Conclusions
• Several large development projects over the last 30 years –
but no significant deployment, apart from use of flash butt
welding in former Soviet Union
• Some processes require very large equipment, which can
be impractical for larger pipe diameters
• Equipment often has to be designed for a specific pipe size
• Relatively slow thermal cycle for all processes, which
results in soft HAZ for high strength linepipe
• Issues with HAZ toughness for some processes
• Current development of FRIEX and friction stir welding
appear to have potential
66
67
Hyperbaric Repair Welding
• 250 bar chamber (equivalent to 2.5 km water depth) – world’s highest pressure hyperbaric chamber, £2m facility
• World first PAW and GMA welds at 250 bar
• Fundamental studies on process and metallurgy
• Successful sea trials in Norwegian Fjord – pipe sleeve repair and hot tap at 300 m msw
• Culmination of 20 years research at Cranfield
Subsea pipeline connection
• Schematic: Pipe support frames and welding habitat for tie-
ins on Nord Stream pipeline. 68
69
Subsea Hot Tap Installation
• Subsea Hot Tap Connection
• Tee
• Valve
• Gooseneck Clamp • Cost-Effective Solution
• 10 Hot Taps carried out to date in
North Sea: 2 on Statpipe
• Currently all installed by divers &
welder-divers (up to 200m)
• CHALLENGE
Diverless Retrofit Tee for
Hot Tap Application
70
Diverless Retrofit Tee Design
• Remote Tee, Tensioned around the Pipe
• Load Transmitted via the Tee Structure
• Internal Weld Primarily for Sealing
Remote Welding Tool Launch
Classification: Internal Status: Draft
• Launch from Deck for Subsea Operation
• Dedicated Launch & Recovery System
• Umbilical supplies Power, Gas, Comms
Electron beam welding
• Reduced pressure electron
beam (rpeb) welding
developed by TWI. Does
not require high vacuum
• Applied to pipe welding by
TWI for Saipem
• High quality welds
possible, with adequate
toughness if filler wire used
• Not used for pipelay –
superseded by more
flexible multi-head Presto
GMA mechanised welding
system
72
Laser/GMA hybrid pipe welding • Laser provides penetration and high
speed, GMA provides filler metal
and increased tolerance to fit-up
• Early developments with CO2 and
Nd-YAG lasers, but introduction of
high power fibre (and disc) lasers
seem practical for site applications
IPG 8kW fibre laser at Cranfield University Vietz laser pipe welding system
73
Laser – Arc Hybrid welding for X70 seamless pipe in J-Lay (pipe vertical) applications
Objectives
• Make root run welds at very
high speeds (4 m/min) and 6
mm ligament
• Make root run welds at high
speeds (2 m/min) and high
ligament of 12 mm
• Complete welds with
conventional GMAW
• Apply full range of DNV
procedure tests to determine
weld acceptability
Hybrid laser-arc welding head
Cranfield University
74
High root ligament thickness laser hybrid pipe root welding
• 11 mm thick root ligament achieved
in 5G position at 2 m/min with 5.2
kW laser power and 9 mm root
face, 25 mm wall thickness X70
pipe
• Welding completed with 9 GMAW
passes by Serimax
• Full procedure tests performed –
welds acceptable to DNV OSF101
• Higher thickness welds are possible
at higher laser power, but limited
mixing of filler metal at bottom of
weld can result in poor properties
75
Conclusions – Power beam welding
• Reduced pressure electron beam welding
successfully developed, but not applied. Issues
with cost, versatility and properties
• Hybrid laser GMA root welding with fibre/disc
lasers shown to be feasible, with productivity
advantages
• Full thickness laser welding possible at higher
laser powers – but issues with weld properties
76
77
Belgium pipeline explosion
Gas pipeline explosion in
Gellingen, Belgium
5 km from explosion in Novyi Urengoi on 18 March 2007 78
Russian Pipeline explosion
79
USA Pipeline Explosion
San Francisco gas pipeline explosion, 12th September 2010
• Gas and oil consumption is still rising at 3.5% per
year, with no signs of decreasing – new pipeline
installations will continue with investments of 20
billion Euros per year
• If this continues, the global temperature rise will be
greater than four degrees by the end of the century,
with disastrous effects for the planet
• Pipelines could be used to carry CO2 for underground
storage
80
The Future?
