Pipeline Technology Journal 2/2014

September 2014
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reliability, cost and quality, leads to offerings
beyond your expectations.
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Industry & Practice
• Reports about new
technological developments
• Personnel and administrative
developments
• New projects and progresses
ISSN 2196-4300
Research / Development / Technology
• Energy Security in Caspian Region
• Towards Greener Materials In Pipeline Concrete Coatings
• Advancing through the ages: Co-
extruded three-ply tape systems
• High-Efficient Heating Concepts
• Integrity Management of Polymer
Lined Water Injection Pipelines
• pipelines vs earthquakes:
design challanges
Conferences / Seminars / Exhibitions
• Review: Pipeline Technology
Conference ptc 2014 in Berlin
• Upcoming: International Pipeline
Seminar Middle East
• Save the date: International pipeline events in 2015
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C
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Editorial
Pipelines – future energy backbones and investments with no regret
Driven by market mechanisms the natural gas grid has grown rapidly over the last
decades. These infrastructure investments can reveal their benefits in the decades to come:
The pipeline system is the backbone for:
•
the gas supply of distributed generation units such as micro CHPs
or fuel cell heating systems
•
the integration of renewables gas like biomethane or of excess power from wind
and solar via electrolysis or methanation
Prof. Dr. Gerald Linke CEO of DVGW
DVGW German Technical and Scientific
Association for Gas and Water
•
extended clean mobility based on proven CNG technology or mobile LNG units
•
a better convergence of the power and the natural gas industry
to combine the strengths of both.
However, there do exist future outlooks according to which the importance of the natural gas pipeline system is declining.
In general, two main arguments are stressed:
•
natural gas is a fossil fuel and its consumption should be reduced over time to match carbon reduction targets
•
future demand for heating would tend to Zero due to improved insulation of buildings.
But natural gas has the lowest emission among all fossil fuels and it should not be concealed that the activation of wind or solar plants
causes emission too. Natural gas infrastructure provides additional benefits – especially where other techniques fail - like in case of
large scale and long-term energy storage.
The WEO has studies how an increased utilization of natural gas and of the existing capable infrastructure can lead to a reduction of
emissions. Also other researchers have proved that the costs for saving one ton of CO2 are significantly lower when the utilization
of modern gas appliances is pushed forward, when power-to-gas technologies are fosters to design the emission profile of the gas
accordingly instead of an investment into insulation of premises. Therefore, the natural gas system remains a warrantor for a safe &
reliable, an environmentally sustainable and – last but not least - affordable future energy supply – an option without regret that can
enfolds its strengths in a sensible interaction with power and renewables.
Yours Sincerely,
see also http://www.dvgw-innovation.de
Advisory Committee Chairmen
Dr. Klaus Ritter, President, EITEP
- Euro Institute for Information and
Technology Transfer
Uwe Ringel, Managing Director,
ONTRAS-VNG Gastransport
Advisory Committee Members
Waleed Al-Shuaib, Manager
Support Services Group (S&EK),
Kuwait Oil Company (KOC)
Juan Arzuaga, Executive Secretary,
IPLOCA
Hermann Rosen, President,
ROSEN Group
Carlo Maria Spinelli, Technology
Planner, eni gas & power
Arthur Braga, Director, RB&B
Consulting
Uwe Breig, Member of the Executive Board / BU Utility Tunnelling ,
Herrenknecht
Tobias Walk, Director Instrumentation, Automation & Telecom/
IT-Systems, ILF Consulting
Engineers
Heinz Watzka, Senior Advisor,
EITEP - Euro Institute for
Information and Technology
Transfer
Hans-Joachim de la Camp, Head of
Dept. Pipelines, Authorized Inspector, TГњV SГњD Industrie Service
Ricardo Dias de Souza, Oil Engineer - Senior Advisor, Petrobras /
Transpetro
Manfred Bast, Managing Director,
GASCADE Gastransport
Filippo Cinelli, Senior Marketing
Manager, GE Oil & Gas
Andreas Haskamp, Pipeline
Joint Venture Management, BP
Europa SE
Dr. Andreas Helget, Business
Solutions Line Head for Pipelines,
Siemens
Jens Focke, Head of Sales &
Marketing, GEOMAGIC
Dr. Hans-Georg Hillenbrand,
Director Sales, Europipe
Jörg Himmerich, Managing
Director / Technical Expert, Dr.-Ing.
Veenker Ing.-ges.
Maximilian Hofmann, Managing
Director, MAX STREICHER
Dr. Thomas HГјwener, Managing
Director Technical Services, Open
Grid Europe
Cliff Johnson, President, PRCI
- Pipeline Research Council
International
Mark David Iden, Director,
Charterford House
Dirk Jedziny, Vice President - Head
of Cluster Ruhr North, Evonik
Industries
Frank Rathlev, Manager of Network
Operations, Thyssengas
Dr. Gerhard Knauf, Head of Div.
Mech. Eng., Salzgitter Mannesmann Forschung / Secretary
General EPRG
Wolfgang Krieg, President, NDT
Global
Reinhold Krumnack, Div. Head,
DVGW - German Technical and
Scientific Association for Gas &
Water
MuhammadAli Trabulsi, former
General Manager Pipelines, Saudi
Aramco
Conference Management
Dennis Fandrich, Director Conferences, Euro Institute for Information and Technology Transfer
Prof. Dr. Joachim MГјller-Kirchenbauer, Head of Dept. Gas Supply,
TU Clausthal
Editorial
Dr. Michael Neiser, Head of StratePipeline technology
journal
- September 2014
gic Business Segment
Infrastructure, TГњV NORD Systems
3
10
44
38
16
Content 2/2014
Industry & Practice
10
Power of Siberia Russia-China Pipeline Construction launched
11
Czech NET4GAS Increases Reverse-Flow Capacity for Central and Eastern Europe
12
Baker Hughes Acquires Weatherford’s Pipeline and Specialty Services Business
13
Pembina Pipeline Corporation Increases Capacity of Phase III
Pipeline Expansion and Secures Additional Volumes
14
ROMAT: ROSEN`s novel Pipe Material Characterization Service
15
GE and Accenture Announce Breakthrough Industrial Internet Technology
for Safer, More Efficient Oil and Gas Pipeline Operations
16
Improving Hard Spot Detection, Characterization, & Prioritization
Comprehensive Inline Inspection with Multiple Dataset Platform
17
Leak Testing Goes Online with Esders LIVE Cloud Technology
15
54
17
66
Research / Development / Technology
20
Energy Security Struggle In Caspian Region From The View Of Important Pipeline Projects
34
Towards Greener Materials In Pipeline Concrete Coatings
38
Advancing through the ages: Co-extruded three-ply tape systems
44
High-Efficient Heating Concept For Long-Distance Pipeline Transport Of Waxy / High Pour Point Crude Oil
54
Integrity Management of Polymer Lined Water Injection Pipelines: Case Study
66
Designing onshore high-pressure gas pipelines against the geohazard of
bearthquake induced slope instabilities
Conferences / Seminars / Exhibitions
88
Review of the 9th Pipeline Technology Conference 2014 in Berlin
90
Join the next Pipeline Technology Seminar Middle East in November 2014, Abu Dhabi
92
Kuwait - the next hub in the Middle East
94
International infrastructure and pipeline events 2014
PTJ goes
interactive!
now with integrated
videofiles
Flawless
by Rosen. It can
A flaw detector
efects in a gas
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В© by Gazprom
Industry & Practice
Alberta / Canada
Pembina Pipeline Corporation
Increases Capacity of Phase III
Pipeline Expansion and Secures
Additional Volumes
Page 13
London / England
GE and Accenture Announce
Breakthrough Industrial Internet
Technology for More Efficient Oil
and Gas Pipeline Operations
Oakland / USA
Page 15
Improving Hard Spot Detection,
Characterization, & Prioritization
Comprehensive Inline Inspection with
Multiple Dataset Platform by TDW.
Page 16
Lingen / Germany
ROSEN has successfully
introduced a new service
addressing the MAOP
validation for pipelines
Texas / USA
Page 14
Baker Hughes Acquires Weatherford’s Pipeline and Specialty
Services Business
Page 12
8
Industry & Practice
Pipeline Technology Journal - September 2014
Industry & Practice
HaselГјnne / Germany
Leak Testing Goes Online with
Esders LIVE Cloud Technology
Page 17
Eastern Russia
Power of Siberia Russia-China Pipeline Construction launched
Page 10
Czech Republic
Czech NET4GAS Increases Reverse-Flow Capacity for Central and
Eastern Europe
Page 11
Industry & Practice
Pipeline Technology Journal - September 2014
9
Industry & Practice
Power of Siberia Russia-China Pipeline Construction launched
Yakutsk hosted celebrations dedicated
to welding the first joint of the Power of
Siberia gas transmission system (GTS)
meant to be a crucial element of the
gas supply system being built in eastern Russia. The GTS will convey gas from
Play Video
the Yakutia and Irkutsk gas production
centers to the Far East and China.The
attendance was comprised of Russian
President Vladimir Putin, Zhang Gaoli,
First Vice Premier of China’s State Council, Yury Trutnev, Deputy Prime Minister
Russias President Vladimir Putin at the construction site
of the Russian Federation and Presidential Plenipotentiary Envoy to the Far
By late 2018, a 2,200-kilometer pipe-
and power supply costs. The GTS route
Eastern Federal District, Alexey Miller,
line section will be built to connect the
will pass, inter alia, through swampy,
Chairman of the Gazprom Manage-
Chayandinskoye field in Yakutia to the
mountainous and seismically hazard-
ment Committee, Wang Dongjin, Vice
city of Blagoveshchensk on the Rus-
ous areas. The bulk of pipes used in the
President of China National Petroleum
sian-Chinese border. It also planned
construction will be domestically man-
Corporation and Yegor Borisov, Acting
to build sections from the Kovyktin-
ufactured. Some 11,700 experts will be
Head of the Republic of Sakha (Yakutia).
skoye field in the Irkutsk Region to
engaged within Phase 1 of the Power of
the Chayandinskoye field (around 800
Siberia project and some 3,000 employ-
The Power of Siberia gas pipeline will
kilometers) and from the town of Svo-
ees will ensure the pipeline’s operation.
run nearly 4,000 kilometers through
bodny in the Amur Region to the city of
five Russian constituent entities: the Ir-
Khabarovsk (around 1,000 kilometers).
kutsk Region, the Republic of Sakha (Ya-
In this way, Power of Siberia will be con-
kutia), the Amur Region, the Jewish Au-
nected. The GTS route will run in par-
tonomous Region and the Khabarovsk
allel with the Eastern Siberia – Pacific
Territory and have an annual capacity
Ocean operational oil pipeline, thus en-
of 38 billion cubic meters of gas.
abling to streamline the infrastructure
10
Industry & Practice
Contact
Gazprom
+7 495 719-10-77
[email protected]
Pipeline Technology Journal - September 2014
Industry & Practice
Czech NET4GAS Increases Reverse-Flow Capacity for Central and Eastern Europe
NET4GAS will bolster capacities at the
line with our commitment to rein-
ease to 780 GWh per day. The invest-
LanЕѕhot border transfer station for the
forcing the energy security not only
ment will strengthen the energy secu-
reverse flow of natural gas in the west-
in the Czech Republic, but also in the
rity in CEE countries. NET4GAS has in
east direction (in the direction of Slova-
CEE region as a whole” says NET4GAS’s
parallel started discussions with the
kia) by close to five million cubic me-
CEO Andreas Rau. Work on increasing
adjacent gas transmission system op-
ters per day starting on 16 September
reverse-flow capacity for the transmis-
erators in Germany in order to analyze
2014. This measure is a result of high
sion of natural gas in the west-east di-
short-term and long-term possibilities
demand for additional reverse flow ca-
rection (to Slovakia) began at the end
for enhancing also physical entry ca-
pacities in the first half of 2014 and it is
of June. Starting on 16 September 2014,
pacities into the Czech Republic.
also intended to mitigate potential lim-
the NET4GAS transmission system at
itations of gas transit through Ukraine
the LanЕѕhot exit point will feature a ca-
Contact
in the upcoming winter season. “The
pacity nearly five million cubic meters
venture is another case in point of in-
per day higher than its current output.
vestments made by NET4GAS into the
t means that the current capacity of ap-
Czech transmission infrastructure in
proximately 730 GWh per day will incr-
Milan Е�epka
NET4GAS, s.r.o.
+420 220 221 111
[email protected]
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9/11/2014 12:49:53 PM
Pipeline Technology Journal - September 2014
11
Industry & Practice
Baker Hughes Acquires Weatherford’s Pipeline and Specialty Services Business
Baker Hughes Incorporated and Weath-
“This acquisition adds sophisticat-
the focus and service delivery to our
erford International plc announced
ed subsea pipeline commissioning
pipeline and specialty services cus-
that they have closed the previous-
services and new ultrasonic inline
tomers worldwide and allows for
ly announced purchase and sale of
inspection technologies to the Baker
growth opportunities for the em-
Weatherford’s pipeline and specialty
Hughes portfolio,” said Martin Craig-
ployees. This transaction also demon-
services business. The acquisition pro-
head, Chairman and Chief Executive Of-
strates the execution capabilities of
vides Baker Hughes with an expanded
ficer of Baker Hughes. “Expanding our
the Weatherford team and is another
range of pre-comissioning, deepwater
services will allow us to more effec-
important step in our restructuring
and in-line inspection services world-
tively address our customers’ process
efforts this year. All proceeds will be
wide. The addition of over 700 pro-
and pipeline challenges.” Comment-
used to pay down outstanding debt.”
cess and pipeline specialists to Baker
ing on the closing of this transaction,
Hughes’ Process and Pipeline Services
Bernard J. Duroc-Danner, President
Contact
further enhances the company’s ability
and Chief Executive Officer of Weather-
to provide innovative solutions for oil
ford, stated, “We are pleased with the
and gas asset owners and operators,
closing of this transaction with Baker
upstream, midstream and downstream.
Hughes. This combination enhances
Melanie Kania
Baker Hughes
+1 713 439 8303
[email protected]
10th Pipeline Technology
Conference
Pipeline
Technology
8-10 June 2015, Estrel,
Berlin, Germany
Conference
2010
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iti pe’s
on
on Lea
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Pi on
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ec e a
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olo
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s
Ex
Play Video
More Information: www.pipeline-conference.com
Euro Institute for Information
and Technology Transfer
12
Industry & Practice
Pipeline Technology Journal - September 2014
Industry & Practice
Pembina Pipeline Corporation Increases Capacity of Phase III
Pipeline Expansion and Secures Additional Volumes
Pembina Pipeline Corporation an-
has secured an additional 59,000 bpd
Combined, Pembina expects to incur
nounced that due to strong customer
under contract. With these commit-
additional capital expenditures for the
demand, it plans to expand its pre-
ments, total volumes under contract
additional 16” diameter pipeline and
viously announced Phase III pipeline
are approximately 289,000 bpd, or 69
the Wapiti to Kakwa Pipeline of approx-
expansions by constructing a new 16”
percent of the initial combined ca-
imately $435 million, bringing total esti-
diameter pipeline from Fox Creek, Al-
pacity. The proposed Wapiti to Kakwa
mated capital for the Phase III Expansion
berta into Namao, Alberta and a new
Pipeline is intended to debottleneck a
to $2.44 billion. Pembina submitted its
12” diameter pipeline from Wapiti, Al-
portion of Pembina’s existing pipeline
regulatory application for both pipe-
berta into Kakwa, Alberta (the “Wapiti
system. It will be approximately 70 km
lines from Fox Creek to Namao on Sep-
to Kakwa Pipeline”).
in length and is expected to have an
tember 2, 2014.
initial capacity of approximately 95,000
The 16” diameter pipeline will span ap-
bpd. This debottleneck will ultimately
Contact
proximately 270 kilometres (“km”) in
allow product to be delivered into the
length and be built in the same right-
Company’s core segment of the Phase
of-way as the proposed 24” diameter
III Expansion between Fox Creek and
Pembina Pipeline Corporation
+1 (403) 231-7500
[email protected]
pipeline from Fox Creek to Namao.
Namao. As part of this project, Pembi-
Pembina expects the two pipelines to
na also plans to build two new pump
initially have a combined capacity of
stations. Subject to regulatory ap-
420,000 barrels per day (“bpd”) and an
proval, Pembina expects the Wapiti to
ultimate capacity of over 680,000 bpd
Kakwa Pipeline to be in-service in late-
with the addition of midpoint pump
2016 to mid-2017, consistent with the
stations. Since December 2013, Pembina
timing of the initial expansion.
@
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Pembina Pipeline Corporation Increases Capacity of Phase III Pipeline Expansion and Secures Additional Volumes
Industry & Practice
Pipeline Technology Journal - September 2014
13
Industry & Practice
ROMAT: ROSEN`s novel Pipe Material Characterization Service
ROSEN has successfully introduced a
Technologies should be made available
In January 2014, a first in-line inspection
new service addressing the MAOP vali-
that can be applied on ILI tools or in the
was performed in a 16” natural gas pipe-
dation for pipelines. ROMAT is the novel
ditch. The new ROSEN service answers
line. For this pipeline only incomplete
Pipe Materials Characterization Service
this need. One element of the service
records were available. Certain sections
offered utilizing a newly developed
is the application of a newly developed
were known to be X42, X52 and X60.
specialized In-Line Inspection (ILI) tool
tool. The measurement principle uti-
However various sections consisted of
capable of identifying and differenti-
lized is based on an electromagnetic
unknown pipe grades. The ILI data was
ating pipeline steel grades. In order to
sensor technology where eddy cur-
processed and analyzed and used to
reliable assess the mechanical integrity
rents are applied in a pre-magnetized
identify different steel grades. First ex-
of a given line material properties must
pipeline wall. The signal obtained from
cavations further confirmed the validity
be known. Records must be complete,
the eddy current sensors are processed
of the system. Further details will be pre-
traceable and verifiable.Especially for
with ROSEN proprietary algorithms so
sented at the upcoming International
some older lines, built before the 1970`s
that the yields strength is measured in
Pipeline Conference & Exposition (IPC)
this information is not available. A R&D
high resolution over the entire circum-
in Calgary starting September 29th.
forum recently organized by PHMSA
ference with a sample distance of up
and held in Chicago has thus identi-
to 2.5 mm. All measurements obtained
Contact
fied a great need for a non-destructive
from a specific joint are then used to
methodology in order to determine ma-
calculate one single value for each in-
terial properties of pipelines. Tech
dividual joint.
Michael Beller
Rosen Group
+49-591-9136-7042
[email protected]
Figure 1: CAD sketch of the new 16” material characterization tool
Figure 2: Color scan of the pipe grade measurement.
The different steel grades are clearly visible.
Play Video
14
Industry & Practice
Pipeline Technology Journal - September 2014
Industry & Practice
GE and Accenture Announce Breakthrough Industrial Internet Technology
for Safer, More Efficient Oil and Gas Pipeline Operations
Play Video
GE and Accenture announced the
“We need an agile and comprehensive
from shale formations. Pipeline com-
launch of the Intelligent Pipeline Solu-
pipeline solution that could be de-
panies are investing up to $40 billion a
tion, the first-ever Industrial Internet of-
livered quickly and allows for a more
year to expand, maintain and modern-
fering to help pipeline operators make
real-time view of pipeline integrity
ize existing infrastructure. To help make
better decisions concerning the condi-
across our interstate natural gas pipe-
the most of these significant invest-
tion of their critical machines and as-
lines,” said Shawn Patterson, president,
ments, operators increasingly require
sets in the oil and gas pipeline industry.
operations and project delivery, Colum-
more robust data, real-time workforce
It combines Pipeline Management, a GE
bia Pipeline Group. Current transmis-
planning and information to optimize
Predictivity software solution powered
sion pipeline infrastructure stretches
the safe performance of these net-
by the PredixTM platform, with Accen-
across nearly 2 million miles globally.
works and relevant systems. The Intelli-
ture’s digital technology and systems
Considerable amounts of natural gas
gent Pipeline Solution is the first indus-
integration capabilities, to help cus-
transported in the United States are
try solution co-developed and brought
tomers make better, faster decisions
coming from the Marcellus and Utica
to market as part of a strategic global
on their pipeline operations to improve
shale plays, and operators like Colum-
alliance formed by GE and Accenture in
safety and prevent costly downtime.
bia are looking for ways to keep up with
2013. Together they will develop tech-
Columbia Pipeline Group (CPG), strate-
current demand. Much of the U.S. pipe-
nology and analytics applications that
gically located within the Marcellus and
line infrastructure has been in place for
help wide-ranging industries take ad-
Utica shale plays, will be the first cus-
at least 20 years, and operators are tak-
vantage of the massive amounts of data
tomer to implement this breakthrough
ing added precautions to ensure safety
generated through business operations.
technology across its network of 15,000
remains at the forefront when trans-
miles of interstate natural gas pipelines.
porting increased production volumes
Industry & Practice
Pipeline Technology Journal - September 2014
Contact
Lindsey Benton
GE Oil & Gas
+ 281 921 5123
[email protected]
15
Industry & Practice
Improving Hard Spot Detection, Characterization, & Prioritization
Comprehensive Inline Inspection with Multiple Dataset Platform
Pipeline hard spots: created due to lo-
pipeline solutions provider T.D. Wil-
ment where one, two, or even three
calized quenching of steel during the
liamson (TDW) – to provide improved
technologies may not be sufficient to
manufacturing process. A potential
detection and characterization of its
detect, characterize, size, and prioritize
threat to pipeline integrity, hard spots
hard spot integrity threats. The technol-
given integrity threats. The MDS inspec-
can become brittle and crack with time
ogy selected was the Multiple Dataset
tion analysis confirmed the operator’s
and under certain conditions. As such,
Platform (MDS) with SpirALLВ® Magnetic
suspicion: cracking within hard spots.
operators with an environment condu-
Flux Leakage (SMFL). MDS utilizes mul-
Due to the advanced char- acterization
cive to the development of these cracks
tiple technologies, on the same tool, to
offered through the overlapping inspec-
are very interested in detecting and ad-
overcome the limitations of individual
tion data, the operator was able to prior-
dressing the threat before they contrib
inspection technologies. The platform
itize the hard spots and address as
Multiple Dataset Inspection Platform with SpirALL MFL from TDW
ute to a failure event. A major US pipe-
includes Deformation, High Field Axial
needed. The MDS platform, engineered
line operator recently suspected hard
Magnetic Flux Leakage (MFL), Patented
by TDW, has been used to detect integrity
spots with potential for cracking on a
SpirALLВ® MFL, Low Field Axial MFL, and
threats such as hook cracks, lack-of-fusion,
section of one of its 30-inch pipelines.
XYZ Mapping. Each technology on the
selective seam weld corrosion, mechan-
The operator needed the ability to not
platform provides a unique assessment
ical damage, and axially-extended metal
only locate the hard spots, but to detect
of an integrity threat. In this case, the
loss. As a result of this innovative technol-
cracking initiated within the hard spots
Low-Field MFL provides primary detec-
ogy, pipeline operators are looking to the
themselves. This level of characteriza-
tion of hard spots, High Field MFL con-
potential of MDS to help solve detection
tion would provide the operator with
firms, and SpirALLВ® MFL identifies any
and characterization challenges with a va-
a means to prioritize, allowing the op-
crack-like defects within the hard spots.
riety of additional integrity threats.
erator to address the most critical hard
In addition, the data collected by the
spots first. As part of the commit- ment
MDS platform is captured, synchronized
to safe and reliable operation, the oper-
and analyzed in a single software, pro-
ator requested support from global
viding a unique comprehensive assess-
16
Industry & Practice
Contact
Chuck Harris
T.D. Williamson
[email protected]
Pipeline Technology Journal - September 2014
Industry & Practice
Leak Testing Goes Online with Esders LIVE Cloud Technology
Esders GmbH announces the market
makes data readings available simulta-
and an Android device. Remote data
launching of Esders LIVE cloud technol-
neously to all involved parties, either
readout from the server and supply
ogy which will be presented at gat, a
on site or at remote locations using any
of user-defined test documentation
gas industry symposium held in Karls-
internet-capable computer or mobile
from the server are realized by the
ruhe from 30 September to 1 October
Android terminal. Bernd Esders adds:
same path. The completed test report
2014. Esders LIVE utilizes automated
“For service providers, gas works and
is displayed in PDF file format directly
data storage and processing by a cen-
pipeline installers, this translates to
on the terminal. The display is normal-
tral server to provide virtual real-time
significant time savings and big cost
ly sufficient for acceptance inspection
availability of leak test data taken on
advantages”.
purposes, i.e. paper print-outs are not
site. Used to support pressure tests
required on site in most cases. In addi-
and leak rate surveys, LIVE accelerates
Test Reports Provided Immediately in
tion to the test reports, the test data
workflow as a whole starting with ac-
PDF Format.
are also available online for inspection
ceptance inspection and going right on
as necessary. Automatic updates are
through to invoicing. The automated
Esders LIVE makes use of a dedicated app
provided to ensure that the latest Es-
data stream also eliminates error sourc-
for data exchange between the test in-
ders LIVE version is in use at all times.
es typically encountered in monitoring,
strument, whether Bluetooth-equipped
Esders LIVE also fulfills high standards
reporting, transmission and evaluation
or combined with an EBTM Esders Blue-
in the area of data security: The test
of data taken on sites.
tooth Module, and the server. Installa-
data is transmitted in encoded form
tion of local software is not required as
and processed and stored exclusively
“Esders LIVE provides users maximum
data in Esders LIVE are available to any
in TГњV-certified computer centres lo-
independence and flexibility in test
terminal with browser-based web ac-
cated in Germany. Esders GmbH will
data storage and retrieval”, explains
cess. The user sends the test readings to
present Esders LIVE at the gat Sympo-
Bernd Esders, Managing Director of Es-
the server by means of the EBTM module
sium in Karlsruhe / Germany.
ders GmbH. In many instances, pipeline
leak testing involves on-site storage
of data readings in the test instrument
which are retrieved at week’s end in
the office or transferred by means of an
USB flash drive. As a result, evaluation of
Contact
Christian Wopen
Sputnik GmbH
+49 251 / 62 55 61-21
[email protected]
results and their documentation in reports can require much work as well as
time-consuming administration.
Esders GmbH has already smoothed
the way considerably in this regard
with their EBTM Esders Bluetooth Module which enables readout of test data
and direct transmission from the survey
site. With their new cloud technology,
Esders goes a step further. Esders LIVE
Industry & Practice
Pipeline Technology Journal - September 2014
17
PII Pipeline Solutions
a GE Oil & Gas and Al Shaheen joint venture
Play Video
MagneScan capabilities
keep expanding
The latest MagneScanв„ў in-line inspection tools continue to impress after more than four years in operation. This fourth
generation MFL technology from PII is shorter, lighter and more flexible than ever before, and deliver a higher level
of data quality. The size range is now extended up to 36 inches with enhanced variable gas bypass capability in the
larger diameters to enable full inspection of high-speed gas pipelines with no loss of production.
MagneScan combines multiple inspections in a single run. The foundation MFL inspection is complemented by a
fully integrated high-resolution caliper and a GIS mapping unit as a standard option for improved data alignment.
The corrosion detection capability is 5% of wall thickness at 90% POD, while depth-sizing accuracy is В±10% at 90%
certainty at tool speeds up to 5 m/s.
To complement the multi-mission hardware capability, PII has developed software for flexible processing, analysis
and reporting. Analysts and pipeline operators can see all data sets aligned together in the latest version of the client
viewing software. Similarly, the new single integrated report covers all data sets and can include integrity engineering
recommendations if requested. The result is a fast reporting interval with a fully integrated inspection and integrity
assessment to facilitate timely planning.
2014 report card
Performance
• Serving customers in: Australia, Austria, Belgium, Canada, China,
Croatia, Czech Republic, Denmark, France, Germany, Holland,
Indonesia, Ireland, Italy, Luxembourg, Mexico, New Zealand, Norway,
Qatar, Saudi Arabia, South Africa, Spain, Switzerland, UK, USA
• Total inspections: 750+ inspections
• Pipeline diameters: 6, 8, 10, 12, 14, 16, 17, 18, 24, 30, 32, 34, 36
• Total distance inspected: 33,000+ km (20,500+ miles)
• Longest run: 385 km (240 miles)
• Pipe: onshore & offshore, seam welded, spiral welded, seamless
• Media: condensate, CO2, crude oil, diesel, jet fuel, natural gas,
naphtha, nitrogen, water
• First runs success: 95%
• Dig verification: 150+ digs, 1,000+ features, 90%+ in tolerance
confirmed around the world
The full MagneScan system (hardware, software and
analysis) continues to exceed pipeline operators’
expectations around the world – with performance covering
categories of features that are typically not visible to
traditional MFL systems. MagneScan’s ability to detect and
size pinholes and axial slots, and previously undetectable
weld defects was confirmed in dig verification data from the
earliest inspections:
• At the end of 2011, a 2 mm deep, 5 mm diameter pinhole
was reported and verified in a 14" 139 km pipeline in
Australia.
The combination of dig verification data and blind-test
results completed in partnership with operators worldwide
has conclusively demonstrated the system’s capabilities
regarding previously sub-specification features (i.e. pinholes,
axial and circumferential slots). PII is therefore publishing
an improved specification covering these additional feature
classes recognized by both API & POF.
As the system’s proven capabilities continue to expand,
further specification and reporting enhancements are
anticipated in the near future.
• PII partnered with a Canadian gas operator to further
investigate identification of axial slots. In a blind test, the
system repeatedly detected axial slots less than 1 mm
wide and even detected features as narrow as 0.4 mm.
• A Chinese operator used MagneScan to study spiral
weld anomalies in late 2011, and a US operator used the
system to assess girth weld defects in a large diameter
gas pipeline in early 2012. Again, MagneScan demonstrated
its outstanding capability to detect, discriminate and size
features within the weld area – including circumferential crack
openings of only 0.25 mm.
MagneScan brings together critical aspects of metal loss inspection
and analysis – including highly accurate detection and sizing, precise
data alignment, GPS location and feature prioritization for verification
and planning.
Research / Development / Technology
Energy Security Struggle In Caspian Region From The View Of
Important Pipeline Projects
Oguzhan Akyener, Turkey Energy Strategies and Politics Research Center (TESPAM)
Abstract
Introduction
Geographically, by involving the countries having important
Caspian Region involves the countries with important ener-
portion of oil and gas reserves of the world, Caspian is an im-
gy resources (oil & gas), which attracts all major energy play-
portant region from the sight of energy. In addition to have
ers of the world. As a result of this appeal on the energy re-
huge oil and gas reserves potential, standing between too
sources; from the view of supply and demand security, there
important energy demanding markets; such as Europe-Chi-
is a critical balance and very complex struggle among these
na and India, increase the geo-political importance of the
major players.
Caspian Region.Hence, having an attractive geo-political
importance due to the existing energy resources of the re-
To analyze the oil and gas supply-demand balances in the
gion, Caspian magnetizes nearly all of the important energy
field of energy security policies: first of all; it is better to de-
players of the world.
fine the main players of the region. Furthermore, in order
to evaluate the long-term development plans; it is very im-
Important Players In Energy Struggle in
portant to examine the planned and existing transferring
Caspian Region
infrastructure in the region (pipelines, ports, transformation
To elect important energy players in Caspian Region; poten-
facilities, railroads, etc.).
tial suppliers in the region, huge consumers importing from
In this study, initially, by mentioning the importance of Caspian Region for world energy
markets, portfolios of the important players
who are active and who want to be active in
this region will be analyzed. Secondly, definitions of energy security for each important
players in the region will be determined and
Russia, Azerbaijan, Iran, Turkmenistan, Kazakhstan, Uzbekistan, India, China & EU can be accepted
as the main important players in
the energy struggle in Caspian
Region.
the region and other politically dominant
governments have studied. Interests of
these players in the region can be observed from oil/gas import – export values, private E&P or service companies
working in the region and political attitudes. Russia, Azerbaijan, Iran, Turkmen-
possible targets for each player’s energy security definitions
istan, Kazakhstan & Uzbekistan are the countries having im-
will be estimated. For analyzing these targets and also the
portant energy resources potential existing in the region. In-
struggle observed for these targets; after mentioning the
dia-China and European Union (EU) can be accepted as the
relevant resource development plans and the supply/de-
important energy demander (importers) countries through
mand potentials, the situations of the existing and planned
the region. US & Japan are the other important energy play-
transportation capacities of the pipelines will be described.
ers which are also active in Caspian Region with their private
By this way, the results of the struggle in energy security in
oil & gas companies (other than important levels of oil/gas
the region will be tried to be predicted.
imports like EU-China and India).
20
Research / Development / Technology
Pipeline Technology Journal - September 2014
Research / Development / Technology
Hence not being importer or exporter, locating too far from
Note that: Due to very few activities and interests in the re-
the region and other geographical conditions, US & Japan
gion, some important international energy players such as
will not be considered as important energy players in the
Canada, Australia, Saudi Arabia, Iraq, South Korea etc. are not
struggle in Caspian Region. Indeed, from the sight of parallel
taken into account.
political attitudes, US can be accepted at the same side with
As a result, as shown on the map below; Russia, Azerbaijan,
EU. US is one of the main dominant countries in the region.
Iran, Turkmenistan, Kazakhstan, Uzbekistan, India, China &
By the way, from the energy politics side; US directly supports
EU can be accepted as the main important players in the en-
EU benefits in order to weaken Russia & China.)
ergy struggle in Caspian Region.
billion $
%
30
1728
265
-1463
0.021
Supply
1.3
19.7
9.5
-10.2
0.015
Supply
231.3
0.30
Dependent
Russia
Iran
Kazakhstan
Uzbekistan
0.6
68
82
14
0.041
x
1.1
56.9
47.9
-9
0.052
Supply
104.7
0.21
Dependent
157
87.2
3680
10643
1971
3174
-1709
2758
0.008
0.056
Supply
Demand
33.6
1.3
160.5
40.2
156.1
54.6
-4.4
14.4
0.005
0.031
Supply
Demand
997.4
4784
0.19
0.01
Dependent Dependent
EU
tcm
bcma
bcma
bcma
7
0.6
872
222
93
100
-779
-122
0.045
0.133
Supply
Supply
0.9
17.5
15.6
64.4
8.5
23.3
-7.1
-41.1
0.017
0.004
Supply
Supply
98
47.5
0.38
0.64
Dependent Dependent
China
billion bbl
m bbld
m bbld
m bbld
India
Proved Oil Reserves
Oil Production
Oil Consumption
Demand Valume
1 year Prod/Reserves
RESULT
Proved Gas Reserves
Gas Production
Gas Consumption
Demand Volume
1 year Prod/Reserves
RESULT
GDP
Oil & Gas Rate in GDP
RESULT
Turkmenistan
Azerbaijan
Figure 1: Important Players in Energy Struggle in Caspian Region
5.7
894
3652
2758
0.056
Demand
1.3
40.2
54.6
14.4
0.031
Demand
4784
0.01
x
17.3
4155
10581
6426
0.086
Demand
3.1
107.2
146.6
39.4
0.035
Demand
12380
0.02
x
7.9
1762
12700
10938
0.080
Demand
1.9
153
456
303
0.081
Demand
15630
0.01
x
Table 1: Table1: Energy Statistics of the Main Energy Players in Caspian Region
Research / Development / Technology
Pipeline Technology Journal - September 2014
21
Research / Development / Technology
The reserves, productions, consumptions, demand value
dencies of each players of oil and gas production is given
(consumption-production), 1 year total production/reserves
in the table1 above. The table below shows the future gas
values (which will give information about the development
consumption estimates of important gas consumers.
and investment rate on the resources) and the GDP depen-
OECD
North America
United States
Europe
Pacific
Japan
Non-OECD
E. Europe / Eurasia
Russia
Asia
China
India
Middle East
Africa
Latin America
Brazil
World
European Union
2008
2015
2020
2025
2030
1.541
815
662
555
170
100
1.608
701
453
341
85
42
335
1000
131
25
3.149
536
1.615
841
661
574
200
118
2.070
755
474
576
247
81
428
139
172
48
3.685
553
1.691
872
668
608
210
122
2.328
786
487
715
335
104
470
154
203
66
4.019
587
1.773
924
700
636
213
123
2.611
824
504
864
430
134
536
164
224
76
4.384
609
1.865
986
741
653
226
127
2.912
857
522
1049
535
176
592
170
245
88
4.478
621
Table 2: 2035 World Gas Consumptions2 (units are bcma)
The figure below shows the changes in oil import values of the biggest consumers in 2035. Again from the figure below, the huge increase expectations in India’s and China’s oil exports in 2035 in contrast to the decrease in EU, US and Japan is observed.
Figure 2: World Oil Imports
22
Research / Development / Technology
Pipeline Technology Journal - September 2014
Research / Development / Technology
From the suppliers’ side in the Caspian region, table below
2035 there will be a decrease in Azerbaijan’s and Russia’s
shows the oil and gas export potential estimates of the
oil export capacities (mainly due to production decline in
Caspian energy suppliers in 2035. As seen from the table, in
mature fields). For gas export potentials; all the players will
increase their supplies.
Oil (bbld)
Gas (bcma)
Azerbaijan
250.000
40
Turkmenistan
250.000
140
Uzbekistan
0
80
Kazakhstan
2.100.000
60
Iran
No Estimations
Due To Sanctions
Russia
6.000.000
350
Table 3: 2035 Caspian Energy Suppliers’ Export Estimations
Energy Security Definitions For Each Player
For both import and export to be continuous, secure and
economic; diversification of resources and markets, decreas-
Generally, for an exporter country, energy security means;
ing transportation costs, obtaining political-economic stabil-
to be able to economically and safely continue to export
ity are important. That’s why these factors are important
her resources. In the opposite side, for an importer country;
energy security issues for all players. To briefly describe
to be able to economically and safely continue to import
main energy security definitions for each players in the
demanded resources.
region:
Azerbaijan
•
•
Picture by Urek Meniashvili 1
oil exporting capacity more than 750 000 bbld.
as exporting capacity more than 7 bcma.
Due to existing & planned pipeline projects and geopolitical conditions Azerbaijan becomes the energy gate of Caspian
Energy Resources to Europe (Although it is more economical to transport some energy resources in Caspian Region
to Europe through Iran or Russia, due to EU & US strategies, Azerbaijan is the unique political choice.) New resource
potentials are mainly gas and all are usually deep offshore. (Means: not easy to develop.) International huge oil companies
are interested for investment
Main energy security targets are:
To develop new offshore gas field with the foreign investors and to gain access to European gas markets via the planned pipelines
To be an important gas supplier for EU and by this way get EU’s & US’s political supports
To continue to securely access existing markets: for gas - to Turkey and Georgia; for oil - to Ceyhan, Supsa & Novorossiysk
To get more production with new investments and development plans from the most important oil field ACG
To have more control over the existing and future projects in Azerbaijan
To construct more offshore drilling platforms for continuous development activities in Caspian Sea
To reach gas export capacity of 50 bcma in 2035
To solve conflicting claims over the maritime and seabed boundaries of Caspian Sea with Iran & Turkmenistan
To be an energy hub in the coming 30 years by transporting Turkmenistan and Kazakhstan oil & gas resources
To construct the region’s biggest refinery and become an important oil products supplier in the region
To construct gas power plants and become an electric supplier in the region
Research / Development / Technology
Pipeline Technology Journal - September 2014
23
Research / Development / Technology
Turkmenistan
•
•
•
•
•
•
•
•
oil exporting capacity more than 100 000 bbld.
gas exporting capacity more than 40 bcma
Lack of sufficient foreign investment
Locating too far from the important markets
Lack of sufficient oil export pipeline infrastructure
Majority of gas is exported to Russia and some portion of gas is exported to China and Iran
Important portion of gas reservoirs are high pressure and temperature reservoirs and have high percentages of H2S
and CO2; means not easy to develop due to economical & technical aspects
Due to important gas reserves having attraction of all other players in the region
Main energy security targets are:
To get attraction of new foreign investors and develop more gas fields.
To continue to securely access to Russia, Iran and China gas markets
To increase the capacity of transportation to access China gas markets
To access to Pakistan, India and European gas markets via planned pipelines
To complete the construction of these relevant pipelines (TAPI & Trans Caspian)
To reach gas export capacity of 230 bcma in 2035 (expected to be more than 140 bcma)
To reach oil export capacity over 1 million bbld in 2035 (expected to be more than 250 000 bbld
(due to expected increasing condensate production; but new infrastructures to transport will be needed)
To complete East-West pipeline inside Turkmenistan and have the ability to transport South East resources to the Caspian Sea markets
(Then from Trans Caspian to EU (also seems uneconomic))
To solve conflicting claims over the maritime and seabed boundaries of Caspian Sea with Iran & Azerbaijan
Uzbekistan
• gas exporting capacity more than 9 bcma.
• Lack of sufficient foreign investment
• Locating too far from the important markets and land locked in all sides
• Lack of sufficient export pipeline infrastructure
• Majority of gas is exported to Russia and some portion of gas is exported to China and Iran
• Important portion of gas reservoirs are high pressure and temperature reservoirs and have high
• percentages of H2S and CO2; means not easy to develop due to economical & technical aspects
• Due to important gas reserves, having attraction of all other players in the region
Main energy security targets are:
To get attraction of new foreign investors and develop more oil and gas fields.
To continue to securely access to Russia, Kazakhstan & Kyrgyzstan gas markets
To increase the capacity of transportation to access Russia gas markets
To access to China gas markets via Central Asia-China Pipeline after capacity extension
To reach gas export capacity of 80 bcma in 2035
In the short term; increase gas to liquid converting processes to reduce oil importing
To explore and develop possible oil shale reserves
To construct new facilities to decrease flaring of associated gas and increase usage (Today nearly 2 bcma gas is flared)
24
Research / Development / Technology
Pipeline Technology Journal - September 2014
Research / Development / Technology
Kazakhstan
•
•
•
•
•
•
•
oil exporting capacity more than 1,4 million bbld.
gas exporting capacity more than 10 bcma.
International huge oil companies are interested for investment but also there are some obscurities
on legal regulations
An important oil exporter for European Markets (with more than % 50 of oil production)
and also China (more than %15)
All gas exports are transported to Russia (Mainly for gas processing plants)
Geographically important dependency to Russia for oil exports
More than 85 percent of gas produced in Kazakhstan is associated gas.
Nearly 5 bcma part of gas production is reinjected.
Main energy security targets are:
To continue to securely access to existing oil markets through Russia,
Azerbaijan and also China oil markets
To develop the giant oil field Kashagan and continue developing of new phases of
other 2 giant fields; Tengiz & Karachaganak
To reach oil export capacity of 2,5 million bbld in 2035
To have more control over the existing and future projects in Kazakhstan
To increase the capacity of transportation to access China oil markets
To complete the construction of Eskene-Aktau Pipeline for domestic oil transportation, and domestic natural gas pipeline system for
gas distribution and for meeting the gas import demand from Uzbekistan and Russia
To construct Trans Caspian and Kazakhstan-Turkmenistan-Iran Oil Pipelines for market diversification of oil exports
To reach gas export capacity of 60 bcma in 2035
Iran
Iran holds the world’s largest proven gas reserves and world’s fourth largest proven oil reserves..
Iran is a very important oil & gas exporter in the region and is a member of OPEC:
oil exporting capacity more than 1,7 million bbld.
gas exporting capacity more than 10 bcma. (Only Turkey is importing gas from Iran.)
•
•
•
Holds the Strait of Hormuz; which is an important route for oil exports of Persian Gulf Countries.
International sanctions negatively affected all parts of the oil and gas market in Iran including; the export & import
movements, development of new fields, new transportation projects, foreign investments and etc. (For example: In
spite of the above oil export capacity, today Iran can export less than 800 000 bbld)
If Iran cannot find a peaceful solution to stop the sanctions and change all scenarios, then the main energy
security targets can be:
Access to existing oil markets which are %50 China & India, %20 Japan & N. Korea and %20 Turkey & Spain & Italy & Greece
Find some back-doors to perforate the sanctions. Such as:
- More swap agreements in oil & gas trade movements
- To increase the swap capacity; making investments in anti US & EU countries
Prepare suitable legal legislations for foreign investors to make investment in development projects in Iran
Develop shared reservoirs as specially; South Pars Field.
- By developing gas fields, export the gas as LNG by constructing relevant facilities
- Make agreements with Turkey to sell extra gas, develop the transportation capacities and make Turkey to construct an LNG facility
if needed
- Make suitable agreements with Pakistan for gas export
Research / Development / Technology
Pipeline Technology Journal - September 2014
25
Research / Development / Technology
Russia
•
•
•
•
•
•
•
•
Russia holds the world’s second largest proven gas reserves and world’s ninth largest proven oil reserves
oil exporting capacity more than 7,4 million bbld.
gas exporting capacity more than 175 bcma.
Russia – EU’s largest energy resources importer (2009)
36% of the EU’s total gas imports originate from Russia
31% of the EU’s total crude oil imports originate from Russia
30% of the EU’s coal imports originate from Russia
The EU – Russia’s largest trade partner for energy goods5
80% of all Russian oil exports go to the EU
70% of all Russian gas exports go to the EU
50% of all Russian coal exports go to the EU
Most part of Russian sector of the Caspian Sea are unexplored and undeveloped
but may hold large hydrocarbon reserves
Most important oil producing fields in Russia are mature and having a declining production trend
Russia has an extensive domestic and export pipeline network.
Main energy security targets are:
To continue to securely access to existing oil and gas markets (mainly EU, China, Japan, Turkey)
To continue the market share volumes, dominance and influence on EU oil & gas markets
By importing oil or gas from Turkmenistan – Kazakhstan & Uzbekistan, increase export capacity
(also buy cheaper and sell with higher prices)
Get prepared for oil & gas supply infrastructure for the increasing demand in China
For having an alternative gas route to Central Europe, avoiding Ukraine’s territory, construct south stream gas pipeline
Make investment to explore new oil & gas resources
Use the technology, some enhanced recovery methods and make investment for new phases of development to avoid
decreasing production trends in the important mature oil fields
To reach gas export capacity of 230 bcma in 2035 (expected to be more than 140 bcma)
To reach oil export capacity over 1 million bbld in 2035 (expected to be more than 250 000 bbld
(due to expected increasing condensate production; but new infrastructures to transport will be needed)
To complete East-West pipeline inside Turkmenistan and have the ability to transport South East resources to the Caspian Sea markets
(Then from Trans Caspian to EU (also seems uneconomic))
To solve conflicting claims over the maritime and seabed boundaries of Caspian Sea with Iran & Azerbaijan
Picture by Минеева Ю. (Julmin) / Surendil 1
26
Research / Development / Technology
Pipeline Technology Journal - September 2014
Research / Development / Technology
India
•
•
•
•
•
•
•
•
India is the fourth largest energy consumer in the world after US, China and Russia
oil importing capacity more than 2,7 million bbld.
gas importing capacity more than 14 bcma.
Most of the oil imports are supplied from Middle East Countries (%64)
and only lower than %64 rate is coming from Iran.
All natural gas demands are met by (usually long term) LNG imports and the
internal gas production. (In 2011 India was the 6th largest LNG importer in the world)
There is an important incremental rate in oil and gas demand for India.
Also India is an important oil importer, due to the refinery capacity; she is a net exporter of petroleum products
Up to 2.6 tcm unconventional gas resources (coalbed methane) potential is estimated to exist in onshore and
offshore India
Main energy security targets are:
Meet the increasing energy demands
Make India an energy independent country:
Development and exploration of unconventional resources (such as coalbed methane and shale gas)
Investment on new exploration and development projects
Decrease the usage percentage of motor fuels
Energy efficiency
Make investments on gas pipeline infrastructure to meet the increasing gas demand
Construct TAPI pipeline and import Turkmenistan gas
If there is a solution on the US sanctions of Iran; construct IPI (Iran-Pakistan-India) Pipeline to import Iranian gas
Increase LNG terminals import capacities and make more long-term agreements with the sellers.
With the Indian oil and gas companies take part in important oil and gas E&P projects all over the world.
China
•
•
•
•
•
•
China is the world’s most populous country and the largest energy consumer in the world. Rapidly increasing
energy demand has made China extremely influential in world energy markets.
oil importing capacity more than 6,4 million bbld.
gas importing capacity more than 40 bcma
Most of the oil imports are supplied from Middle East Countries (%50) and from Caspian suppliers; %10 from Iran,
%7 from Russia, %4 from Kazakhstan.
There is an important incremental rate in oil and gas demand for China.
Up to 10 tcm unconventional gas resources (coalbed methane) potential is estimated to exist in prospects
Main energy security targets are:
Meet the increasing energy demands diversify supply sources, make long term contracts
Development and exploration of unconventional resources
Set domestic wholesale energy prices
Investment on new exploration and development projects by mostly focusing on western interior provinces and offshore fields.
Apply enhanced recovery methods for mature fields and improve energy efficiency
Make investments on construction and integration of domestic oil & gas pipeline infrastructure
Increase the oil supply capacity from Russia & Kazakhstan and gas supply capacity from Turkmenistan
Make the relevant agreements and build pipelines for gas supply from Russia to China
Construct an oil import pipeline from Myanmar to bypass the potential choke point of Strait of Malacca
In the short term complete the construction of gas pipeline from Myanmar (with a capacity of 12 bcma)
With the Chinese oil and gas companies take part in important oil and gas E&P projects all over the world.
Increase gas storage capacity up to 32 bcm
Solve territorial disputes with Japan
Research / Development / Technology
Pipeline Technology Journal - September 2014
27
Research / Development / Technology
European Union
•
•
•
•
•
•
•
•
EU is the largest energy consumer structure in the world.
Most important oil & gas importer in the world
oil importing capacity more than 10 million bbld.
gas importing capacity more than 300 bcma.
36% of the EU’s total gas imports originate from Russia and around %28 is from Norway and other important
portion is from Algeria, Qatar, Nigeria and Libya.
A central gas import system and policy exists for the union.
31% of the EU’s total crude oil imports originate from Russia and around % 10 from Norway and other imports
are originate mainly from Libya, Saudi Arabia, Kazakhstan & Iran, Nigeria, Azerbaijan, Iraq and other middle east
countries.
Some members of EU is directly dependent on Russian gas import, this situation becomes a strategic constraint for
the union’s energy security issues
Main energy security targets are:
Continue to meet the energy demands in a sustainable, competitive and secure way
Less greenhouse gas and carbon emissions.
Use more biofuels
Increase market competition.
Focus on the Caspian gas market and work on potential supply
possibilities for diversity of resources:
For the initial step transport Azerbaijan gas to EU (with SCPX-TANAP-TAP)
For the second step; transport Azerbaijan future gas to EU
(after extending the capacities of existing pipelines and also construct IAP)
For the third step; transport Iraq or/and East Mediterranean Sea gas to EU
(after the extension of constructed infrastructure in the previous steps and
also construct Nabucco West) For the fourth step; transport Turkmenistan gas
to EU (Trans Caspian) (but seems not-economic)
Check for other gas supply potentials via pipeline or LNG
Develop a Strategic Energy Technology Plan to develop technologies in
areas including renewable energy, energy conservation, low-energy buildings, fourth generation nuclear reactor,
clean coal and carbon capture.
Develop an Africa-Europe Energy partnership for the continent to be a sustainable energy supplier for EU
Decrease gas imports, increase efficiency, use more renewables
Develop and implement common energy policies with the EU
28
Research / Development / Technology
Pipeline Technology Journal - September 2014
Research / Development / Technology
Important Pipelines In The Region & Capacities
From
Through
To (Markets)
Capacity
(bcma)
SCP
GAZI-MAGOMED-MAZDOK
BAKU-ASTARA
Azerbaijan
Azerbaijan
Azerbaijan
AZ-GEO
AZ-RUS
AZ-IRAN
Turkey
Russia
Malcjcovam
8
1
0,5
Future
SCPX
TANAP
TAP
IAP
Azerbaijan
Georgia
Turkey
Albania
AZ-Geo
Turkey
Gre-Alb
Mont-Bosn
Turkey-EU
EU
Italy
Balkans
16
16
10
5
Existing
CAC
KORPEZHE KK
DAULETABAT-KANGIRAN
CENTRAL ASIA-CHINA
BUKHARA-URALS
Turkmenistan
Turkmenistan
Turkmenistan
Turkmenistan
Turkmenistan
Turk-Uzb-Kaz
Turk
Turk
Turk-Uzb-Kaz
Turk-Uzb-Kaz
Russia
Iran
Iran
China
Russia
100
13
6
40
20
Future
EAST-WEST
TAPI
TRANSCASPIAN
CENTRAL ASIA-CHINA X
Turkmenistan
Turkmenistan
Turkmenistan
Uzbekistan
Turk
Turk-Afg-Pak
Az
Uzb
Caspian
India
Turkey-EU
China
30
34
30
+18
Existing
CAC
BUKHARA-URALS
TASHKENT-BISK-ALMATI
Turkmenistan
Turkmenistan
Uzbekistan
Turk-Uzb
Turk-Uzb-Kaz
Uzb-Krg
CACX
CENTRAL-ASIA-CHINA X
Uzbekistan
Uzbekistan
Uzb
Uzb
Russia
China
+30
+10
From
BTC
WREP
NREP
Railway
Azerbaijan
Azerbaijan
Azerbaijan
Azerbaijan
Existing
Kazakhstan
Kazakhstan
Kazakhstan
Kazakhstan
Rus
Kaz
Kaz
Kaz
World
China
Caspian
Russia
0,7
0,24
0,34
0,6
BUKHARA-URALS
CAC
CENTRAL-ASIA_CHINA
Turkmenistan
Turkmenistan
Turkmenistan
Turk-Uzb-Kaz
Turk-Uzb-Kaz
Turk-Uzb-Kaz
Russia
Russia
China
20
100
40
ESKENE-AKTAU
KAZAK-CHINA X
TRANSCASPIAN
KAZAK-TURKMEN-IRAN
CPC X
Kazakhstan
Kazakhstan
Kazakhstan
Kazakhstan
Kazakhstan
Kaz
Kaz
Kaz
Kaz-Turk
Rus
Caspian
China
World
Iran
World
0,76
0,16
x
x
+0,7
KAZAK-CHINA
Kazakhstan
Kaz
China
x
KORPEZHE KK
DAULETABAT-KANGIRAN
IRAN-Turkey
Turkmenistan
Turkmenistan
Iran
Turk
Turk
IR
Iran
Iran
Turkey
13
6
14
IRAN-PAKISTAN
IRAN-IRAQ-SYRIA
Iran
Iran
IR
IR-IRQ-SYR
Pakistan
World
28
x
YAMAL1
YAMAL2
BLUE STREAM
NORTH CAUCASUS
ORENBURG-WESTERN BORDER
URENGOY-UZHGOROD
YAMBURG-WESTERN BORDER
DOLINA UZHGOROD
KOMARNO-DROZDOWICHI
UZHGOROD-BEREGOVO
HUST-SATU-MARE
Russia
Russia
Russia
Russia
Russia
Russia
Russia
Russia
Russia
Russia
Russia
Bel
Bel
Rus
Geo
Ukr
Ukr
Ukr
Ukr
Bel
Ukr
Ukr
EU
EU
Turkey
Armenia
EU
EU
EU
EU
EU
EU
EU
28,5
28,5
16
10
26
28
28
20
5
11
2
ANANYEV - TIRASPOL'-IZMAIL &
SHEBELINKA-IZMAIL
Russia
Ukr
EU
24
KOBRIN-BREST
ST. PETERSBURG-FINLAND
Russia
Russia
Bel
Rus
EU
EU
5
7
SOUTH STREAM
ALTAI
RUSSIA-CHINA 1&2
Russia
Russia
Russia
Rus
Rus
Rus
Eu
China
China
63
30
80
Exiting
CPC
KAZAK-CHINA
RAILWAY
UZEn-ATYRAU-SAMARA
Future
Future
Existing
Name of Pipeline
Name of Pipeline
Russia
Russia
Russia
Russia
Bel-Ukr-Eu
Rus
Bel
Rus
Future
Existing
DRUZHBA
BALTIC
NORTH-WESTERN
ESPO
Russia
Gas
To
Capacity
Through (Markets (million
)
bbld)
AZ-GEO-TR World
1,2
AZ-GEO
World
0,15
AZ-RUS
World
0,3
AZ-GEO
World
0,22
Future
Iran
Kazakhstan
Uzbekistan
Turkmenistan
Azerbaijan
Oil
Research / Development / Technology
EU
World
EU
Pacific
2
2,1
0,3
0,6
Pipeline Technology Journal - September 2014
29
Research / Development / Technology
Oil
Through
Name of Pipeline
From
Through
To (Markets)
Capacity
(bcma)
TAPI
Turkmenistan
Turk-Afg-Pak
India
34
IPI
Iran
Pak
India
x
Future
From
Future
KAZAK-CHINA
Kazakhstan
Kaz
China
0,24
CENTRAL ASIA-CHINA
Turkmenistan
Turk-Uzb
China
40
KAZAK-CHINA X
MYANMAR-CHINA
Kazakhstan
Myanmar
Kaz
Myn
China
China
+0,16
0,48
CENTRAL ASIA-CHINA X
KAZAK-CHINA
RUSSIA-CHINA 1&2
MYANMAR-CHINA
Uzbekistan
Kazakhstan
Russia
Myanmar
Uzb
Kaz
Rus
Myn
China
China
China
China
+10+18
x
80
12
DRUZHBA
NORT-WESTERN
Russia
Russia
Bel-Ukr-Eu
Bel
EU
EU
2
0,3
YAMAL 1
YAMAL 2
BLUE STREAM
NORTH CAUCASUS
ORENBURG-WESTERN-BORDER
URENGOY-UZHGOROD
YAMBURG-WESTERN BORDER
DOLINA-UZHGOROD
KOMARNO-DROZDOWICHI
UZHGOROD-BEREGOVO
HUST-SATU-MARE
Russia
Russia
Russia
Russia
Russia
Russia
Russia
Russia
Russia
Russia
Russia
Bel
Bel
Rus
Geo
Ukr
Ukr
Ukr
Ukr
Bel
Ukr
Ukr
EU
EU
Turkey
Armenia
EU
EU
EU
EU
EU
EU
EU
28,5
28,5
16
10
26
28
28
20
5
11
2
ANANYEV-TIRASPOL' IZMAIL &
SHEBELINKA IZMAIL
Russia
Ukr
EU
24
KOBRIn-BREST
ST. PETERSBURG-FINLAND
MAGHREB
MEGDAZ
GALSI
TRANS-MEDITERRANEAN
GREENSTREAM
Russia
Russia
Algeria
Algeria
Algeria
Algeria
Libya
Bel
Rus
Mor
Alg
Alg
Tun
Lib
EU
EU
EU
EU
EU
EU
EU
5
7
12
8
10
30
11
TANAP
TAP
IAP
SOUTH STREAM
NABUCCO WEST
Georgia
Turkey
Albania
Russia
Turkey
Turkey
Gre-Alb
Mont-Bosn
Rus
EU
EU
Italy
Balkans
EU
EU
16
10
5
63
20
Future
EU
Existing
China
Existing
India
Name of Pipeline
Gas
To
Capacity
(Markets (million
)
bbld)
Table 4: Caspian Energy Players and existing & future pipeline capacities
To check all the players’ 2035 extra supply and demand potentials on the figures 2 & 3 below
(2035 value – todays value)
Figure 2: 2035 Extra Gas Supplies and Demands
30
Research / Development / Technology
Pipeline Technology Journal - September 2014
Research / Development / Technology
Figure 3: 2035 Extra Oil Supplies and Demands (unit million bbl/d)
In 2035:
•
EU does not need extra oil supply so; main item for EU energy security is gas.
•
China and India need very important amount of oil supply and they will not meet their demand only from the
Caspian Region. Moreover, oil supply in the Caspian region will decrease (as 1,2 million bbl/d) in spite of the
expected production increase in Kazakhstan. (By considering there will not be a solution in sanctions on Iran. If a
solution to the sanctions can be found, Iran will change all the oil supply potential in the region. Otherwise, India
and China will have to find oil supplies from Middle East-North America or Africa)
•
From this view, meeting both oil and gas demands are the most important energy security issues for India & China
•
There is totally 428 bcma extra gas supply in Caspian Region players and 895 bcma extra demand. This means
struggle in gas demand security will be deepened.
•
For logical analysis of this struggle also some other items have to be considered such as:
- Other gas demanding markets those can get - There is also going to be a struggle between the gas
supplies from this region; such as Turkey, Japan, Korea and
suppliers in the region (Mainly; between Russia and others)
etc.
- Effect of Unconventional Resources in supply and gas
- Other supply potentials from Africa-North America or
prices
Middle East (but much more extra LNG capacities have to
- Long and short term gas prices effects
be constructed for such an option.)
Pricing, Sale & Contract Mechanisms
- EU policy to diversify the gas supply resources and
- Success Possibilities of Planned Pipelines & Development
mitigating the gas dependency to Russia
Projects
- Iran and Sanctions
Research / Development / Technology
Pipeline Technology Journal - September 2014
31
Research / Development / Technology
After shortly analyzing supply-demand balances in the re-
•
Both China & India do not have enough planned gas
gion between the energy players in 2035, it is observed that
transportation capacities in 2035 to meet their de-
the struggle is going to be mainly on the gas resources and
mands. Both countries can negotiate on having more
gas supply security.
supplies from Turkmenistan &Uzbekistan. For China; always there will be a possibility to have more gas from
Subsequent to selecting gas for evaluating the supply-de-
Kazakhstan and Russia, however, range of extra invest-
mand balances, the other most important factor that is go-
ments and gas prices are important.
ing to determine the results of this struggle
and the changes in the balances are the transportation capacities of the gas pipeline projects. In addition to suitable capacities of the
pipelines, the tariff estimations, transportation
costs and also the market prices have to be
It is observed that there are strug- •
gles and even more important
struggles will happen on gas supply balances between all energy
players of Caspian Region.
considered in analysis.
After checking the future available transportation capacities
•
of pipelines in the region (as assuming future pipeline constructions will successfully be completed), the map below is
prepared, which is showing each suppliers’ transport capacity available in 2035.
EU also will not have enough transportation capacities in 2035. New LNG
projects, Azerbaijan – North Africa and
Eastern Mediterranean gas resources
will be important for EU’s gas security
future.
Russia will have huge amount of extra supply transportation capacity and to EU (Assume South Stream with 63
bcma will be agreed with EU and completed). However,
it will be better for Russia to agree with China, develop
new transportation facilities and export her gas to huge
demander southern neighbor (Also todays sanctions
and political problems have to be taken into consider-
As a result of this map:
ation) to export.
Figure 2: 2035 Extra Gas Supplies and Demands
32
Research / Development / Technology
Pipeline Technology Journal - September 2014
Research / Development / Technology
•
For Turkmenistan, it will be better to increase the
Summary
transportation capacities to India and China and make
•
•
extra exports to those countries. In the EU side; there
Energy supply-demand balances in Caspian Region are very
are important political and economic problems waiting
important and are very carefully be followed by these main
for solutions (economic problems will be more difficult
players of the region. It is very important to analyze todays
to solve due to the pricing regulations of EU and high
and futures supply-demand potential scenarios to be able
tariffs), that’s why gas supply of Turkmenistan to EU
to read correctly these balances. In addition to the supply-
does not seem logical.
demand potentials, transportation capacities in the region
For Uzbekistan and Kazakhstan, both have to decrease
are also very important.
gas exports to Russia and make better sale agreements
As a result of this study, it is observed that there are strug-
with China and increase their pipeline capacities to
gles and even more important struggles will happen on gas
China.
supply balances between all energy players of Caspian Re-
Russia, have to secure her dominancy in all markets and
gion. Pipeline capacities and politics will be important deter-
continue to import Caspian gases
mining key factors among these balances.
Author
OДџuzhan Akyener
TPAO Azerbaijan
AZ 1005
Baku/Azerbaijan
[email protected]
www.tpao.gov.tr/eng/
The Caspian Sea from the orbit
Research / Development / Technology
Pipeline Technology Journal - September 2014
33
Research / Development / Technology
Towards Greener Materials In Pipeline Concrete Coatings
Mohit Jain, GSPL India Transco Limited (GITL)
Pipelines are by far one of the most efficient and safe meth-
blocks affixed to the underwater pipeline, was ineffec-
od of transporting Natural Gas. However, a different field
tive as it lead to wrinkles. The use of Aggregate envelope
condition obligates different laying methodologies for the
type, where geotextile bags filled with heavy aggregates,
same. Dry environments demand such treatment when the
was discontinued owing to its questionable performance
field is rocky (for mechanical protection). Same is the case
in areas with strong water currents and the possibility of
with Wet environments too. Offshore pipelines and pipe-
tearing of bags. It it here when the method concrete coat-
lines at river or lake crossings also need special treamtents
ings come into picture. Concrete with a density of 2200 to
for the same (for alancing buoyancy).
2400 Kg/m3, high strength and durability properties is the
perfect material for coating pipes and imparting weight.
During the course of time, several measures were devised to
control the buoyancy of pipelines (based of the optimum criteria) in marine environment. The optimum criteria for buoyancy control systems can be listed as,
1. the ability to maintain the required level of negative
buoyancy over the entire service life of the pipeline,
2. the ability to be installed within the limited access of
ROU,
3. minimazation of the overall environmental impact of
the project,
4. minimazation of the installation as well as material cost
without affecting the overall quality,
Numerous buoyancy control measures were tried. Each had
their fair share of advantages and deficiencies. For example,
Cast concrete systems which consisted of precast concrete
34
Research / Development / Technology
Pipeline Technology Journal - September 2014
Research / Development / Technology
Pipeline Concrete Coatings
Pipeline Concrete coatings are usually 25 to 150mm thick
and consist of a rebar cage or a wire mesh. The Wire mesh /
fabric is manufactured in rolls or sheets. The weight required
is calculated based on pipe weight and pipe contents
weight incorporating adequate factor of safety (ranging
from 1.1 to 1.5). Then, the coating thickness is calculated
based on the required negative bouyancy required. If the
coating ghickness is less than 50mm then single layer of
reinforcement is used and if it is more than 50mm then two
sets of concentric reinforcements are used (At 1/3rd and 2/3
thickness).
Method 1
There are two methods of applying concrete layer on the
pipe surface.
1. First is the Casting method where the wire sheet
fabric is rolled around the pipe. Then the complete
arrangement is enclosed in a Formwork / Mold with
openings on the top. Concrete is poured from the top
and is vibrated using specialized machines.
2. The second method is impinging, where concrete is
projected at a very high velocity on the external surface
of the pipe containing the wire roll fabric.
Method 2
Cement Replacement
Indian Standards IS 1910 on concrete lining and coating pre-
carbonation etc) and some of its constituents (like Cement)
fers the concrete constituents as Ordinary Portland Cement
are non-environment friendly. It is daunting to note that
(OPC), aggregates and water. However, ordinary concrete is
Portland cement and Iron ore (used for heavy aggregates)
fraught with shortcomings; it sets quickly in warm climates
manufacturing increases CO2 emmisions by 100kg per ton.
and slowly in cold climates, it is adversely affected by miner-
Also, one can always improve mechanical and durability
als (eg. Sulphate attacks, Cloride ingrees,
properties with the use of industrial by-products
Research / Development / Technology
Pipeline Technology Journal - September 2014
35
Research / Development / Technology
like, Fly Ash, GGBFS (Ground Granulated Blast Furnace Slag)
used heavy aggregate currently in use is iron ore (which is
or other metal Slags as a replacement of cement thereby
expensive and degrading to environment). The substitutes
reducing our dependence on an inferior product.
that can be used are iron-rich by-products from metal recovery operations, such as smelters, Waelz kilns or plasma
The construction industry has been known to use GGBFS in
kilns. These by-products have a price ranging 15-70% of the
concrete through high-slag blastfurnace cement (HSBFC)
original heavy iron ore actually used for countering the pipe
or Portland Blast Furnance Cement (PBFC) (Eg. Koteshwar
buoyancy.
hydroelectric projekt, Uttarakhand). Slag Cement (which
is priced at 75% of Portland cement) reduces the risk of
Conclusion
reinforcement corrosion and provides higher resistance to
attacks by sulfate and other chemicals. Also concrete with
In Conclusion, The use of industrial side-products in the
GGBS continues to gain strength over time, and has been
concrete coatings for pipeline has boundless benefits for
shown to double its 28-day strength over periods of 10 to
both the pipeline industry as well as the environment.
12 years leading to extra proteciton to the pipeline. The
The use of industrial by-products in concrete coatings will
material is also known to reduce emissions by 90% thus
result in an improved mechanical as well as durability
helping reduce pollution load on the environment.
performance, thereby providing extra safety to the pipe. It is
also capable of reducing material cost ans CO2 emissions
Both C and F-type fly ashes are being used in concrete in
too, thus complementing a major motive of the natural gas
different parts of the world. A much known example of a
pipeline industry, i.e. protection of the environment.
flyash based marine structure in India is the Nagarjuna Sagar
Dam. C-Type Flyash is preferred due to its hydraulic binding
properties and low prices (35-60% of Portland cement). Fly
Ash based concrete is flowable, offeres highter strength
that its OPC counterparts and is highly durable in marine
environments owing to its exceptional resistance to chloride
ingress, sulphonation and carbonation.
Author
Mohit Jain
Aggregate Replacement
GSPL India Transco
While replacing cement, on ecannot overlook the possibility
Limited (GITL),
of aggregates being replaced by heavier ones, after all con-
GSPL Bhavan,Plot No. E-18,
crete contains 60-80% of aggregates and it is the weight of
GIDC Electronic Estate,
the coating that counters the buoyancy. The most widely
Sector -26,
Gandhinagar - 382 028
Gujarat, India
[email protected]
36
Research / Development / Technology
Pipeline Technology Journal - September 2014
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Research / Development / Technology
Advancing through the ages:
Co-extruded three-ply tape systems
Michael Schad, Denso GmbH, Germany
The cathodic protective current of an active corrosion pro-
Abstract
tection system is designed to counter corrosion if there is
damage to the passive corrosion protection system and it
In recent years, quality requirements for onsite coating ap-
should fail. Passive corrosion protection to protect the bare
plications have increased and new products have been sold
steel of the pipe by wrapping or coating and active corro-
to the market. But it is important to carefully consider coat-
sion protection using cathodic protection therefore form the
ing options in the field.
complementary parts to both sides of a comprehensive steel
pipeline protection scheme.
A variety of pipeline coating technologies are available and
selection has evolved along geographical lines. In North
These functions have been and are achieved using of wa-
America fusion bonded epoxy (FBE) continues to be the most
ter-repellent and almost diffusion-proof materials which are
common coating for mainlines, while in Europe, Asia, Middle
also able to meet the requirements of having sufficient me-
East and South America, 3-layer polyethylene (3LPE) are the
chanical strength and being safe and easy to apply.
dominant type of mainline pipe coatings. These coating decisions are generally based on the operator- or engineering
Coatings of pipelines
company preferences, but follow as well the pipeline construction requirements and operating conditions. Not to for-
The goal is to achieve an equal technical performance level
get tradition and experiences with different kind of coatings
by the field coating to the factory coating, which provides an
made in these specific geographic areas. Up to the 1920s
unbroken chain of quality and security.
steel pipelines were not protected at all, or as a maximum
protected by a bituminous or coal tar based primer or paint
While the field coating provides a high technical perfor-
which caused a lot of trouble due to its unpleasant odour.
mance level on site, its main characteristics include the ease
of onsite application, reducing the risk of human mistakes
Since the late 1920s steel pipelines have been protected
and maintaining a high standard of corrosive and mechan-
against corrosion by a coating or a wrapping. The first real
ical protection at international standards. Besides the re-
passive corrosion system- a petrolatum tape system- was in-
quirements of the operator, we have to pay attention as well
vented in 1927. Thus, access by a corrosive medium to the
for the elementary needs of the contractor who is in charge
steel surface is prevented. This is the primary task of all pas-
to apply and guarantee for the selected coating system.
sive corrosion protection systems.
38
Research / Development / Technology
Pipeline Technology Journal - September 2014
Research / Development / Technology
Three-ply tape systems
remaining interface. This ensures a completely sealed, impermeable, and sleeve-type coating.
State of the art three-ply self-amalgamating tape coatings
have proved their technical quality on innumerable sites
Furthermore, state-of-the-art three-ply asymmetrical corro-
worldwide during the last 40 years in operation. In the case
sion prevention tapes like the new developed DENSOLEN
of changing weather conditions, or in cold or windy climates,
AS30-20 or AS50 tapes have a so-called �four-ply structure’,
tape-coating systems are preferred due to their wide range
containing an additional layer between the carrier film and
of application at temperatures from –40°C (104°F) to 60°C
adhesive. When a three-ply tape is used as an inner wrap lay-
(140В°F).
er for corrosion prevention, damages will not occur. There
will be no risk of spiral corrosion, compared to two-ply tapes
The structure of these three-ply tapes contains a carrier film of
used as an inner wrap layer, incompletely sealed tape over-
stabilised polyethylene, which is coated with a butyl rubber
laps inevitably lead to heavy spiral corrosion followed by
adhesive on both sides. The carrier films are manufactured
complete undermining corrosion. This effect is often shown
with intermediate adhesive layers, ensuring that no interface
if a two-ply tape (PE/PVC carrier with one adhesive side) is
remains between the carrier film and adhesive layer. When
used for corrosion prevention (as an inner wrap). Most of the
three-ply tapes are wrapped around a pipe, the adhesive
very few cases of bad experience with tape coatings are due
layers self- amalgamate in the overlap areas, forming a
to the fact that only a two-ply tape was used as the corrosion
homogenous sleeve-type coating without any
prevention tape, which provides no sealing coating.
Figure 2: Self-amalgamation effect in 3-ply tapes
Research / Development / Technology
Pipeline Technology Journal - September 2014
39
Research / Development / Technology
Figure 2: By using 2-ply tapes for the inner wrap, the chances of spiral corrosion occurring on the steel substrate are significantly higher. This effect can be avoided by using co-extruded 3-ply tape technology
Co-extruded three-ply tapes should be used as a one-tape
The field-joint coatings included petrolatum wax systems,
system or only as the inner wrap of a two-tape system. In
cast bitumen, bitumen tapes, two-ply polyethylene tapes,
a two-tape system, the outer wrap can be a two-ply tape,
and high-performance three-ply tape-systems. Based on
as long as the inner wrap is a three-ply tape. All DENSOLEN
this survey, E.ON Ruhrgas gave recommendations for the se-
tape systems follow this philosophy, which DENSO Germany
lection of field joint coatings which should guarantee long-
has been applying – as the inventor of passive corrosion pre-
term corrosion-protection performance.
vention – for more than 90 years.
During the E.ON Ruhrgas survey, the three-ply tapes showed
Whenever possible, a field coating with properties similar to
excellent
the performance level of the existing factory coating should
which have been the preferred field-joint coating system for
be chosen. One of the highest international standards is the
E.ON Ruhrgas pipelines since 1981, neither showed loss of
stress-class C50 according to the European Norm EN 12068.
adhesion nor decreasing strength.
corrosion protection properties. Those tapes,
The higher peel strength and indentation resistance of this
stress-class will ensure a higher safety level compared to
Field joints under exposed thermal stress
other tape systems or viscoelastic tapes.
Gazprom and Wintershall/WINGAS have a very close techLong-term experience
nical exchange between steering groups for many aspects
of the pipeline business. One major topic is the appropriate
In 2008 E.ON Ruhrgas/Open Grid Europe surveyed 2,000 km
coating of pipelines and field joints under exposed thermal
of its pipeline grid, and the respective field coatings used
stress. Up until now, WINGAS has used co- extruded three-
on these pipe sections. The entire E.ON pipeline grid covers
ply tape technology on all of its transit pipelines with suc-
12,000 km of pipelines constructed between 1912 and 2006.
cess. Gazprom – which has the world’s largest pipeline grid
40
Research / Development / Technology
Pipeline Technology Journal - September 2014
Research / Development / Technology
covering more than 500,000 km – was surprised that WINGAS
prom, excavated two 36 inch diameter pipe sections at the
did not use shrink sleeve technology or thermo-coatings for
STEGAL transit pipeline which was laid between 1991-1992
standard field coatings, as Gazprom’s experts initially could
in the rocky soils of the Erz mountains in Saxony, Germany.
not believe that any advanced co-extruded tape technology
could keep up with the �new’ technologies of thermo- coat-
After 20 years of operation, the joints
ings or visco-elastic material. WINGAS proposed to execute
- covered by a co-extruded three-ply tape
a long-term test on one section of its first constructed pipe-
- were still in excellent shape and even exceeded the values
lines at the end of 2012.
in the EN 12068 stress- class C50.
In November 2012, WINGAS (now Gascade Gastransport), a
Peel tests on site were taken and values measured up to the
subsidiary of Wintershall and Gaz
maximum 59 newton centimetre (N/cm), the corresponding
value according to EN 12068 stress-class C50 is 10 N/cm.
Figure 3: Preparation of peeling test
Figure 4: Peeling Test on site 118N/cm
at STEGAL Pipeline
2cm width = 59N/cm!
After the execution of the peel test, a cohesive break in the
and outer-wraps will use the same tape at 0.8 mm thickness.
layers could be noticed and the remaining layer showed a
Four layers will result in a total system thickness of approxi-
thickness of 342 microns. The tape system used for the STE-
mately 3.2 mm, although the thickness can range from 3.44
GAL pipeline was co-extruded three-ply tape DENSOLEN AS
mm to 3.62 mm.
40 Plus tape, which was one of the first asymmetrical tape
types with a thicker 0.43 mm inner butyl layer to cover the
WINGAS and Gazprom’s engineers were convinced of the ad-
steel substrate better than its symmetrical predecessors. This
vanced co-extruded three-ply tape technology’s efficiency
tape can be applied as a one-tape system in which the inner
and long-term success.
Research / Development / Technology
Pipeline Technology Journal - September 2014
41
Research / Development / Technology
New systems launched
The latest evolution in advanced co- extruded three-ply tech-
The DENSOLEN AS 50 was initially designed as a one-tape
nology are two new systems: the economical DENSOLEN AS
system, passing the stress-class B50 when wrapped in two
30-20 (0.5 mm thick single tape) and the strong and flexible
layers. In combination with DENSOLEN R20HT as outer
high-end DENSOLEN AS 50 (1.1 mm thick single tape).
wrap, the tape-system (to a total thickness of 3.2mm) even
exceeds the stress-class C50, according to EN 12068. Both
The DENSOLEN AS 30-20 is applied as an inner wrap together
new systems hold the respective DIN-DVGW certificates for
with the DENSOLEN R20MP as outer wrap. Applied as a sys-
the stress-classes according to EN 12068.
tem with two layers of each (to a total thickness of 2.0 mm),
the stress-class B50 according to EN 12068 is passed. It is a
very cost efficient system, which has a true corrosion- prevention function (no spiral corrosion, compared to available
two-ply tape systems) and outstanding tape characteristics
(elongation at break).
Figure 5: Application of DENSOLENВ® AS 30-20/R20MP with
engine driven application device DENSOMATВ® 11
Author
Figure 5: Application of Inner Wrap DENSOLENВ® AS 50 with
manual wrapping device DENSOMATВ® KGR
Michael Schad
DENSO GmbH
Leverkusen
35 years and counting
Germany
All co-extruded three-ply tapes and tape systems, which
are in accordance with international standards and under
[email protected]
www.denso.de
constant third-party inspection, fulfil the properties which
pipeline owners expect from the best corrosion-prevention
materials. Co-extruded three-ply tapes and tape systems
have been available for more than 35 years, proving their
outstanding quality and long-term experience as the chosen
technology by international gas and pipeline operators all
over the world.
42
Research / Development / Technology
Pipeline Technology Journal - September 2014
Research / Development / Technology
Trusted Partnership
For four generations, companies around the world have trusted
TDW’s unwavering commitment to pipeline performance.
So can you.
North & South America
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Europe / Africa / Middle East
Asia Pacific
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Research / Development / Technology
Pipeline Technology Journal - September 2014
В® Registered trademark of T.D. Williamson, Inc. in the United States and in other countries. в„ў Trademark of T.D. Williamson, Inc. in the United States and in other countries. В©Copyright 2014 All rights reserved. T.D. Williamson, Inc.
43
High-Efficient Heating Concept For Long-Distance
Pipeline Transport Of Waxy / High Pour Point Crude Oil
Klaus-Dieter Kaufmann, ILF Consulting Engineers, Germany
Abstract
Transporting waxy / high pour point crude oil above its pour
For crude oils with 6.5, 12.5 and 20%wt wax, PPTs of 20В°C,
point temperature (PPT) in heated pipeline systems over
26В°C and 29В°C were reported. Literature reports on waxy
long distances from fields to consumer markets will guaran-
crude oil samples with PPT up to 32В°C, while for a new pipe-
tee successful pumpability when other transportation alter-
line project in Africa, the crude oil discovered is waxy with a
natives will not be applicable or preferable like:
PPT of over 40В°C.
•
dilution with light / low-waxy hydrocarbons
In order to minimize wax built-up on the internal pipeline
•
formation of oil-in water emulsion
surface and to avoid intense operational measures for wax
•
injection of chemical agents (pour point
removal (e.g. frequent runs of scraper pigs) the pipeline
•
depressants, flow improvers, paraffin
system design may require oil transportation above the so-
•
inhibitors or wax crystal modifiers)
called wax appearance temperature (WAT) which is gener-
•
thermal treatment by suitable heating/
ally expected to be 10-20В°C (K) higher than the pour point
cooling cycles or
temperature. A minimum required crude oil temperature
•
crude oil upgrading / thermal cracking.
of up to 65В°C may therefore throughout represent a realistic scenario e.g. when planning to export waxy / high pour
Characteristically, waxy crude oils have undesirably high
point crude oil from central inland oil fields to international
pour points and are difficult to handle (risk of solidification
markets by pipeline.
/ blockages, un-ability to re-start operation) where the flowing
and ambient temperatures are about or less than the pour point.
44
Research / Development / Technology
Pipeline Technology Journal - September 2014
The first section of this article addresses thermally insulated
a) Due to the saw-tooth like axial temperature profile,
pipeline systems and compares heater-station heated
the oil temperature at pipeline section inlet may exceed
pipeline systems with electrically trace heated pipeline
considerably the minimum required oil temperature at its
systems. The second section of this article comprises the
outlet which increases the actual heat losses unnecessarily.
description of a high-efficient pipeline heating system
reducing effectively not only pipeline heating cost but also
b) At lower crude oil flow rate, the inlet temperature to a line
emissions of CO2 and of other exhaust gas components to
section must be increased accordingly in order to maintain
the environment.
the intended minimum outlet temperature. As the maximum
allowable crude oil temperature is usually limited (e.g. in
order to avoid pipeline material overstressing), the pipeline
2. Comparison Of Heating Alternatives For
system cannot not be operated over longer time below a
Pipeline Systems
certain minimum flow rate; this may restrict the flexibility of
such transport system considerably.
2.1 Heater-Station Heated Pipeline Systems
c) In case of low flow rate or interruption of transportation
2.1.1 System Description
operation (shut-down), only limited time will be available
Crude oil heating in stations installed upstream successive
to resume normal operation in order to avoid solidification
pipeline sections with or without heat insulation is one
(gelling) of the crude oil which may prevent re-starting pipe-
of the usually applied heating methods. A high heating
line operation with the pumps installed in the transport sta-
efficiency is possible by direct transfer of fuel combustion
tions. If after that time, resuming normal pipeline operation
heat to the crude oil. The temperature profile along the
wouldn’t be possible, emergency measures must be initiat-
pipeline system resembles hereby a saw-tooth profile with
ed e.g. by displacement of the high pour point crude oil by
the highest temperature at each pipe section inlet (see
e.g. low-pour-point oil or water. This, however, may require a
also Figure 3, upper curve, temperature profile within one
pipeline design incorporating installation of large additional
selected pipeline section).
storage volume for displacement medium and for displaced
highpour point crude.
2.1.2 Disadvantages
The major disadvantages of heating the oil only in pump /
heating stations can be characterized as follows:
Research / Development / Technology
Pipeline Technology Journal - September 2014
45
Research / Development / Technology
2.2 Thermally Insulated and Trace Heated Pipeline Systems
2.2.1 General
Two different thermally insulated (preferentially buried)
pipeline systems are considered in the following (see also
Figure 1).
a) A steel pipeline compund system, thermally insulated by
polyurethane (PUR) foam and externally coated by polythylene, known since many years regarding its fundamental
construction for application in district heating systems and
b) A steel-cased pipeline system (known also as steel-in-steel
or pipe-in-pipe system) insulated by mineral wool or other
special insulation material in the (preferentially evacuated)
ring space between both steel pipes, coated externally by
polyethylene.
Both thermally insulated pipeline systems described above
can be equippend with electrical trace heating systems
having the main advantage that the oil temperature in the
pipeline sections can be maintained independent of flow
conditions like loww-flow or zero flow; trace heating can
even re-heat cooled-down pipeline sections after longer
shut-down.
The schematics in Figure 1 show typical cross sections
through both systems. The trace heating elements (potentially more than one in each system) as well as type and
number of supporting elements of the steel-cased pipeline
system are indicated only schematically and may vary between manufacturers.
Figure 1: Schematical Cross Sections through Trace Heated
and Insulated Pipeline Systems (above: PUR compund
systems; below: steel-cased pipeline systems
In case of a skin effect trace heating system /1/, also known
The “heating tube” comprises an electrically insulated cable
under the acronyms SECT (skin effect current trace heating),
generating heat in the tube near its inner surface due to the
SEHTS (skin effect heat tracing system) or SEHMS (skin effect
alternative electrical current, known as �skin effect’. A related
heat management system) a relatively small “heating tube” is
long-distance heated crude oil transportation system oper-
laid in thermal contact to the crude oil pipeline.
ating at 65В°C has been installed in recent time in India.
46
Research / Development / Technology
Pipeline Technology Journal - September 2014
Research / Development / Technology
The inlet temperature to trace heated pipeline systems
from the external power plant to the trace heated pipeline
should normally correspond to the intended crude oil trans-
sections over longer distances may occur. The low electrical
portation temperature, as trace heating systems are usual-
power generation efficiency causes also related high emis-
ly designed to compensate only heat losses during normal
sions of CO2 and of other exhaust gas components to the
pipeline operation. As this article concentrates preferentially
environment.
on thermally related aspects of heated crude oil transport,
other aspects regarding e.g. mechanical stability, suscepti-
b) The infrastructure for transmission and distribution of
bility to potential damages (e.g. by external impact, mechan-
electrical energy may be susceptible to external influences,
ical failures, corrosion, water ingress), expected life time,
especially in rough area, e.g. damage of highvoltage over-
maintenance requirements, investment cost etc. will not be
head lines by natural or third-party impact which may affect
discussed here further.
the reliability of the heating system; additionally the electromagnetic impact of high-voltage overhead lines installed in
2.2.2 Disadvantages
parallel to pipelines may initiate / promote corrosion dam-
The major disadvantages of electrical trace heating of
ages therein.
long-distance pipeline systems can be characterized as follows:
2.3 Summary Comparison of Heated
Pipeline Systems
a) The electrical energy required for trace heating is usual-
Advantages and disadvantages of heater-station heated ver-
ly generated only at comparably small efficiency related to
sus electrically trace heated insulated (preferentially buried)
combustion energy of the originally used fuel medium. Ad-
pipeline systems at elevated temperatures are shortly sum-
ditionally, electrical transmission and distribution losses
marized in Table 1 below.
Heating System
Heater-Station
Heated System
Electrically Trace
Heated System
Advantages
Common heating method
Disadvantages
Increased heat losses due to increased oil temperature near pipeline section inlet
High heating efficiency
Non-suitability for low flow or shut-down over longer time; minimum required
possible by direct transfer of flow rate restricts system operation flexibility
fuel combustion heat to the
crude oil
Emergency measures avoiding crude oil gelling / solidification may require high
additional storage volumes / investment cost
Ability to maintain the oil
Low overall heating efficiency and related high heating cost
temperature independent
Increased emissions of CO2 and of other exhaust gas components to environment
of flow rate (e.g. low-flow,
zeroflow)
Potential susceptibility of electrical power transport / distribution systems to
Possibility to reheat the oil
external influences
after longer shut-down; safe
and easy start-up
Potential impact of high-voltage overhead lines on pipeline corrosion
Table 1: Advantages and Disadvantages of Heater-Station Heated and Electrically Trace Heated Pipeline Systems
Research / Development / Technology
Pipeline Technology Journal - September 2014
47
Research / Development / Technology
3. Description Of The High Efficient Heating Concept
5. The CHP Stations are designed such (preferentially by installation of two CHP units in parallel per station) that during
3.1 General
extraordinary operation (e.g. very low flow, zero flow or
re-heating of a pipeline system e.g. after long shut-down)
A high-efficient heating concept for long-distance pipeline
the cooled down pipeline system can be heated up until re-
transport of waxy / high pour point crude oil is described in
suming normal pipeline operation using only the electrical
the following aiming to combine the advantages of station
power generated in the CHP Stations for the electrical trace
heated and trace heated buried pipeline systems, incorpo-
heating system; during this special operation, the heat gen-
rating hereby combined heat and power generating (CHP)
erated in the CHP Stations will not be transferred in the ex-
stations as new innovative elements characterized as fol-
haust gas heat exchangers but can be bypassed / disposed
lows:
to ambient air (see also Figure 1).
1. Thermally insulated, electrically trace heated pipeline sys-
6. If appropriate, the transported crude oil itself or a distillate
tem keeping the oil temperature approximately constant at
separated by a topping unit can be used as fuel medium for
a specified transportation temperature, e.g. slightly above
the above mentioned CHP Stations.
the wax appearance temperature (WAT). (Fig. 3, lower curve).
7. Alternatively or supplementary, other heating media like
2. Generation of heat and electrical power in stations allocat-
natural gas (e.g. treated associated gas from oil fields) or
ed along the pipeline in suitable distances (e.g. 15 – 25 km)
diesel oil can be used for supply of above mentioned CHP
for trace heating installations (Fig. 2, lower system); the sta-
Stations.
tions operate according to the principle of combined heat
and power production (CHP) (Fig.4).
8. It can be advantageous to supply the heating medium for
the CHP Stations via a separate preferentially buried pipeline
3. A CHP Station comprises one or more gas engine or gas
laid in parallel to the crude oil pipeline.
turbine driven electrical generator units, fuel cell units or a
combination of such units, arranged in parallel.
9. The buried, thermally insulated and trace heated pipeline
sections are preferentially constructed using one of two
4. During normal pipeline operation, the crude oil heat
different construction principles:
losses are compensated contemporarily by both, electrical
trace heating of the neighbouring pipeline section(s) (by
a) a steel pipeline thermally insulated by polyurethane (PUR)
electrical power generated at CHP Stations) and directly (by
foam, trace heated (e.g. by SECT system) and externally coat-
heat transfer to side stream(s) at CHP Stations), achieving by
ed by polyethylene or
this combination a very high overall heating efficiency of the
pipeline transportation system.
b) a steel-in-steel pipeline system, trace heated (e.g. by SECT
system) and insulated by mineral wool or other special insulation material in the (preferentially evacuated) ring space
between both steel pipes, coated externally by polyethylene.
48
Research / Development / Technology
Pipeline Technology Journal - September 2014
Research / Development / Technology
Figure 2: Schematics of Conventional and CHP Station Heated Pipeline Systems
The selection of either of both pipe construction principles
2. Independency of flow rate (zero-flow, low-flow and heat-
should be performed pipeline section-wise based on a thor-
ing-up conditions can be handled).
ough techno-economical analysis regarding amongst others
the risk of impact by third party, coating joint failures pref-
3. Overall high efficiency of pipeline heating system due to
erentially in contact with water, maintenance/repair and ex-
combined heat and power generation at CHP Stations.
pected lifetime of the system.
4. High reliability of the heating system due to implementa3.2 Advantages
tion of many independent CHP Stations and partial redundancy in CHP Stations by parallel units.
The advantages of the new high efficient heating concept
incorporating CHP Stations:
5. Easy installation of CHP Stations on site possible by
container solutions and simplified maintenance by using
1. Oil transport with exactly definable over-temperature
standardized equipment.
above pour point (PP) or wax appearance temperature
(WAT).
Figure 3: Exemplary Temperature Profiles in one Section of Heated
Pipeline Systems (assumed section end temperature 50В°C)
Research / Development / Technology
Pipeline Technology Journal - September 2014
49
Research / Development / Technology
3.3 Combined Heat and Power (CHP) Station Configuration
ped with two equally designed CHP units installed in parallel and connected via an inlet- and an outlet header to the
Based on usual design conditions for skin effect trace heat-
crude oil transport pipeline. For demonstration of the work-
ing systems, typical distances between combined heat and
ing principle, in each CHP unit, a micro-turnine driven gen-
power (CHP) stations for long waxy / high pour point crude
erator unit provided with fuel via a parallel fuel supply line is
oil pipelines may amount to ca. 15-25 km. Figure 4 shows an
selected. The electrical power generated in the gas turbine
exemplary configuration of a pipeline heating station oper-
/ generator unit is hereby used to provide the trace heating
ating according to the combined heat and power (CHP) gen-
systems of the neighbouring pipeline sections with electri-
eration principle. A typical heater station is hereby equip-
cal energy.
Unit No. 1
Ambient Air
Fuel Medium
Unit
Gas Turbine
Exhaust Gas to Ambient
El. Power
Generator
{To / from Unit No. 2
Hot Exhaust Gas
Exhaust Gas Heat Exchanger
Thermal Oil Circuit
Crude Oil Heat Exchanger
Discharge Header
Suction Header
Trace-Heating System
//////////// Thermal Insulation
Crude Oil Pipeline
Line Valve
Fuel Medium Pipeline
Figure 4: Exemplary Configuration of a Pipeline Heating Station Operating according
to the Combined
Heat
and Power
(CHP) Generation
Principle
Fig.
Example
Configuration
of a CHP
Pipeline Heating Station
50
Research / Development / Technology
Pipeline Technology Journal - September 2014
Research / Development / Technology
Additionally, in each CHP unit, heat is transferred from the
3.4 Friction Heating’ Aspects
hot turbine exhaust gas via two counter-currently operated
heat exchangers and via an intermediate heat transfer medi-
Design calculations for pipeline systems consider often that
um cycle to a crude oil side-stream chich is routed for heat-
the pressure �losses’ along a pipeline system are converted
ing purposes through the heater station. Due to the con-
into dissipation heat which finally contributes to the so-
siderable temperature increase of this side stream (e.g. by
called friction heating effect in a pipeline system. Consider-
30 В°C (K)) de-routed from the main stream, the dimensions
ing, however, the overall low efficiency of mechanical power
of the crude oil side stream piping may be kept relatively
production in pump stations (in relation to the original com-
small (e.g. <=4” for a 24” crude oil pipeline system). After re-
bustion energy content of the fossil fuel used) it becomes
injection of the heated side stream into the main crude oil
clear that trying by intention to �heat’ a pipeline system es-
stream, the main stream temperature increases only slightly
sentially by friction heating would finally result in low overall
but sufficient to maintain the intended temperature level of
heating efficiency. Additionally it has to be respected that
the downstream pipeline section up to the next CHP Station.
the �friction heating’ effect depends considerably (roughly with 3rd power) on the crude oil flow rate, and reduces
In order to avoid any potential liquid losses, hermetically
therefore very fast with flow rate reduction. Assuming a rel-
sealed circulation pumps can be installed in the heater sta-
ative flow rate reduction from 100% to 80% (50%), the heat
tions. The heating stations can be prefabricated as modular
generated by �friction heating’ would reduce from 100% fric-
packaged / container solutions and delivered to site wide-
tion heat to ca. 51% (12.5%). Relying on the friction heating
ly ready for connection and commissioning. Additionally,
effect as a main component of the pipeline heating system
synergy effects regarding infrastructure, site accessibility,
design would therefore be counteractive in regard of dispos-
operation / control and safety of station installations can be
ing on a flexible system operation. In case of an operational
obtained when installing anyhow required sectionalizing
shut-down (zero flow) �friction heating’ wouldn’t work at all.
valves at the sites of the CHP heating stations. It is estimated that depending on the project, the efficiency of pipeline
The considerations described above are also of special im-
heating according to the CHP heating station concept de-
portance for the initial phase of pipeline operation when the
scribed can be increased by a factor of more than 2 (and
flow rate may still be considerably less than the design flow
related emissions to environmental reduced by the same
rate respecting potential tie-in of additional oil discoveries
factor) compared with conventional trace heated pipeline
at a later time. It is therefore concluded that �friction heat-
heating solutions.
ing’ cannot be considered a reasonably efficient alternative
method to the high-efficient heating method using CHP
heating stations in combination with trace heating in pipeline sections.
Research / Development / Technology
Pipeline Technology Journal - September 2014
51
Research / Development / Technology
3.5 Application of CHP Heating Principle
The first section of this article addresses thermally insulated
to Pump- and Heating Stations
pipeline systems and compares heater-station heated pipeline systems with electrically trace heated pipeline systems.
The principle and efficiency of combined heat and power
While heater-station heated transportation systems have the
(CHP) stations as outlined above can analogously be applied
main disadvantage of non-suitability for low flow, zero flow
to pump- and heater stations:
or shut-down over longer time, the overall heating efficiency
of electrically trace heated systems is very low compared to
•
In pump stations, the heat produced in fuelled pump
the fuel combustion energy from which the electrical power
drivers (e.g. combustion motors) or in power gener-
for trace heating was generated.
ator sets/stations (e.g. for energy supply of E-motors
•
for pumps) can be used for crude oil heating via main
The second section of this article comprises the description
stream or side stream heat exchangers
of a high-efficient pipeline heating system incorporating
Crude oil heating stations could be configured accord-
generation of heat and of electrical power (for electrical
ing to the CHP principle; the electrical energy generated
trace heating) in combined heat and power (CHP) stations.
may then be fed into public or private electrical trans-
This concept enables a very high overall heating efficiency,
mission or distribution systems, and may also be used to
reducing effectively not only pipeline trace heating cost (less
supply the trace heating system.
than halving seems possible) but also related emissions of
CO2 and of other exhaust gas components to the environ-
Both applications enable further increase of overall CHP
ment.
generation efficiency and/or economy, respectively.
Application of the CHP heating principle to pump- and
heating stations may further increase efficiency and
Summary
economy of long-distance pipeline systems for transport
Transporting waxy / high pour point crude oil above its pour
of waxy / high pour point crude oil.
point (PP) in heated pipeline systems over long distances
from fields to consumer markets will guarantee successful
pumpability when other transportation alternatives will not
be applicable or preferable.
Author
In order to minimize wax built-up on the internal pipeline
Klaus-Dieter Kaufmann
surface and to avoid intense operational measures for wax
ILF Consulting Engineers
removal (e.g. frequent runs of scraper pigs) the pipeline
Werner-Eckert-Str. 7
system may be designed to operate above the so-called wax
D - 81829 Munich
appearance temperature (WAT) which is considerably higher
than the pour point temperature.
Germany
Tel. +49 89 25 55 94 - 502
[email protected]
52
Research / Development / Technology
Pipeline Technology Journal - September 2014
www.ilf.com
ENGINEERING EXCELLENCE
ILF�s 1,800 employees in more than 30 countries are prepared
to serve their clients in the oil, gas & energy sector.
Research / Development / Technology
Integrity Management of Polymer Lined Water Injection Pipelines:
Case Study
Damir Tadjiev, Mark Murray, Bryce Stewart Wood Group Kenny Caledonia Ltd, UK
Abstract
1. Introduction
1.1 Background
Polymer lined water injection pipelines have proven to be a
cost effective alternative solution to corrosion resistant alloy
For the water injection system main internal corrosion mech-
clad pipelines for subsea applications. At normal operating
anisms are oxygen corrosion, MIC, and CO2 corrosion if pro-
conditions these pipelines are often considered to be at low
duced water is present. The main barrier is material selection
risk from internal corrosion. This is because a polymer liner,
(polymer liner or CRA cladding) and the secondary barrier is
if intact, provides the main barrier to mitigate against the
treatment of seawater (de-aeration and biociding). Polymer
internal corrosion mechanisms, which include oxygen cor-
lined water injection pipelines have proven to be a cost ef-
rosion, MIC, and CO2 corrosion if produced water is present.
fective alternative solution to corrosion resistant alloy clad
pipelines for subsea applications [1]. This involves pulling
This paper presents a case study based on the experience
the liner through the flowline stalks and joining the stalks
from a North Sea asset, where polymer liner at two spot loca-
using specially developed WeldLinkв„ў connectors, as shown
tions was damaged due to the remedial works, exposing the
in Figure 1. For the water injection pipelines operating at
carbon steel to general and localised corrosion. The first part
normal conditions a polymer liner, if intact, provides effec-
of the paper gives system description and history of anomaly
tive main barrier against the internal corrosion mechanisms
identification. The second part of the paper presents details
for the duration of the design life.
of the targeted inspections and summarises findings of the
fitness for service assessment. Inspection involved using an
The case study presented in this paper is based on the ex-
ROV deployed bespoke UT inspection tool, which enabled
perience from a North Sea asset, where the polymer liner at
information on the condition of the pipes at the locations
two spot locations was damaged due to remedial works. This
where the liner was damaged, and allowed estimation of a
compromised the main barrier against internal corrosion,
corrosion rate (up to 1.95 mm/year). Fitness for service as-
exposing the carbon steel to general and localised corrosion
sessment was undertaken using the WGK in-house software
with an estimated rates of up to 1.95 mm/year.
IC Finesse to confirm that the pipelines with anomalies were
fit for continued service, and enabled planning of the remedial works.
54
Research / Development / Technology
Pipeline Technology Journal - September 2014
Research / Development / Technology
1.2 System Description and Design Data
The field is located in 500 m water depths in the West of
Shetland area of the North Sea. There are three remote subsea drill centres and production is achieved from the centre
Floating Production Storage and Offloading (FPSO) vessel.
Each of the drill centres has associated gas and water injection facilities. The water injection system comprises of a
flexible riser and three flowlines connected to the riser via a
subsea manifold, as shown in Figure 2. Treated seawater or a
mixture of treated seawater and produced water is injected
Figure 1: WeldLinkв„ў Schematic
through the riser and splits at the manifold, where each flowline transports it to an individual drill centre.
Figure 2: Water Injection System Layout
The riser has a smooth bore structure (high density polyeth-
lined with Medium Density Polyethylene (MDPE). The design
ylene (HDPE) pressure sheath), the pipework of the struc-
data for the two flowlines where the liner anomalies were
tures (manifold, pullheads, and Flowline Termination Assem-
identified are summarised and the history of anomaly iden-
blies (FTAs)) is Inconel 625 clad API 5L X60 carbon steel or
tification is presented in table 1.
Super Duplex, and the flowlines are API 5L X60 carbon steel
Research / Development / Technology
Pipeline Technology Journal - September 2014
55
Research / Development / Technology
Parameter
Flowline A
Flowline B
Outer Diameter (mm)
273.1
273.1
Wall thickness (mm)
15.8
15.9
Corrosion allowance (mm)
2
1
Manufacturing tolerance, %
10
10
Design factor
0.72
0.72
MAOP (barg)
197
197
Specified minimum yield strength, MPa
413
413
Ultimate Tensile Strength, MPa
517
517
1.5 (FBE + 3 LPP)
2.5 (FBE + 3 LPP)
10 (MDPE)
10 (MDPE)
9.3
9.3
External Coating (mm)
Internal liner (mm)
Minimum allowable wall thickness for hoop
stress as per PD-8010 (2)
Table 1: Water injection flowlines design data
1.3 Anomaly Identification History
The flowline A was installed in two (2 km) parts: the FPSO
section was laid in 1995 and the drill centre section was laid
in 1996; the two parts were connected with a midline flange.
Due to a leak at the FTA, the FPSO section of the flowline had
to be replaced, which required recovery of the existing drill
centre section to the deck. Following this the liner within the
drill centre section was noted to have slipped by approximately 2 m from the end of the Inconel clad section of the
WeldLinkв„ў. General and localised corrosion of the exposed
Figure 3a: Liner slippage on the flowline A
carbon steel area was observed, with the Inconel/carbon
steel interface being most affected as shown in Figure 3a.
Figure 3b: Blistering on the flowline B
56
Research / Development / Technology
Pipeline Technology Journal - September 2014
Research / Development / Technology
The flowline B was installed in 2005 to replace one of the existing flowlines. Due to a leak at the FTA a new section (approximately 500 m) complete with FTA had to be installed
at the drill centre end. This required cutting 500 m section
off the already installed pipeline at the drill centre end and
recovery of the flowline end to the deck for a tie-in welding.
Following this the liner within the drill centre section was
noted to be damaged (blistering and plastic deformation of
the liner over a localised area below the compression ring) as
shown in Figure 3b, presumably due to overheating during
the subsea cutting (diamond wire saw was used).
Figure 4a: Sonomatic ROV-iT tool
(courtesy of Sonomatic)
2. Integrity Management
2.1 Inspection Method and Requirements
Considering what was mentioned above, as of end of 2008,
there were two locations where the polymer liner was known
to be damaged creating increasing risk of failure due to internal corrosion. Inspection of these locations was required
to confirm the extent of corrosion and any further liner regression at the location on the flowline A and to establish if
any corrosion had occurred behind the blistered liner at the
location on the flowline B. It was acknowledged that, due
Figure 4b: Proserv Pipeline Coating Removal
to the uncertainty with regards onset of corrosion, a 2nd in-
(PCR) tool (courtesy of Proserv)
spection would be required, at least for the location on the
flowline A where the liner had slipped.
As shown in Figure 4a, during inspection the Sonomatic UT
The integrity management strategy was revised to include a
targeted external wall thickness inspection. And, due to the
water depths (500 m), the ROV deployed Sonomatic ROV-iT
12 UT tool was chosen. This tool is capable of high resolution corrosion mapping and real-time review of the
inspection results, which enables conclusions with regards to any liner damage and immediate decisions with
regards to further inspection requirement, respectively.
tool sits on top of the pipe. This requires some space underneath and, therefore, dredging of the areas around the inspection locations was required. This was carried out using
the 6 inch ROV dredger. Furthermore, external (polypropylene) coating had to be removed at the inspection locations
to identify the limits of the WeldLinkв„ў connectors and facilitate the UT measurements. This was carried out using the
Proserv’s Pipeline Coating Removal tool (see Figure 4b). It
should be noted here that a CP system assessment was undertaken prior to the coating removal to confirm that the
bare pipe sections would have sufficient protection from external corrosion to the end of field life.
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The inspection areas were specified for both locations to
January 2011 and inspection scope included only two lo-
ensure that corrosion mapping coved the non-clad area of
cations where the liner was known to be damaged. Several
the WeldLinkв„ў connectors and extended to the carbon steel
patches of corrosion were detected for both locations: more
flowline sections; this was approximately 3 m for the location
widespread at the location on the flowline A (Figure 6) and
on the flowline A and 2 m for the location on the flowline B.
predominantly at the 6 o’clock area at the location on the
Figure 5 shows the location of the WeldLinkв„ў connector with
flowline B (Figure 7). The highest wall loss figure obtained for
respect to the FTA flange (WeldLinkв„ў connector is made of
the location on the flowline A was 31.3%, with the minimum
carbon steel, which is Inconel 625 clad from the weld on the
remaining wall thickness of 10.86 mm. And the highest wall
flange to the point shown with a dotted line). As can be seen
loss figure obtained for the location on the flowline B was
from Figure 5 during installation the flowline A was welded
22.6%, with the minimum remaining wall thickness of 12.3
directly onto the FTA, while a pup piece (cut to length at site)
mm. The wall loss figures were consistent with the fact that
was used at the end of the flowline B.
the flowline A had been in service for longer and had more
server liner damage. The built-in corrosion allowance was
2.2 Inspection No 1
consumed, but the remaining wall thicknesses at both locations were above the minimum allowable wall thicknesses
The first inspection was carried out from December 2010 to
for the hoop stress (9.3 mm, see Table 1).
Figure 5a: Schematic showing details of the inspection locations - Flowline A
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Figure 5b: Schematic showing details of the inspection locations - Flowline B
The findings of the first inspection indicated general and lo-
For the two locations with known liner anomalies further
calised corrosion. The fact that the deepest pits were found
corrosion was identified with a number of new pits, mostly
around the Inconel/carbon steel interface suggested galvan-
at the location on the flowline A (see also Figures 6b and 7b).
ic corrosion, which is characterised by fast rates and cannot
The highest wall loss figure obtained for the damaged lin-
be modelled using the industry accepted models. Consid-
er location on the flowline A was 41.1%, with the minimum
ering this, decision was made to re-inspect both locations,
remaining wall thickness of 9.3 mm. And the highest wall
which would enable a more accurate quantification of the
loss figure for the damaged liner location on the flowline B
corrosion rates and, therefore, allow estimation of the re-
was 27.9%, with the minimum remaining wall thickness of
maining service lives.
11.45 mm. For the location on the flowline A the area of the
deepest pit was found at a different location, compared with
2.3 Inspection No 2
the first inspection. For the location on the flowline A the
minimum remaining wall thickness, with the tool resolution
The second inspection was carried out in April-May 2012 and
(В±0.25 mm) applied, was below the minimum allowable wall
inspection scope included not only the two locations where
thickness for the hoop stress (9.3 mm, see Table 1), indicating
the liner was known to be damaged, but also two additional
a requirement for a fitness for service assessment.
(verification) locations, one on the flowline A and one on the
flowline C.
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The inspection results obtained for the two locations with
time of flight diffraction (TOFD) during the second inspec-
no known liner anomalies (verification locations) are shown
tion and wall loss was identified for both locations. For the
in Figure 8. The minimum wall thickness at the verification
location on the flowline A the highest wall loss was 40.5%,
location on the flowline A was measured at 96.6% and the
with the minimum remaining wall thickness of 9.5 mm.
minimum wall thickness at the verification location on the
And for the location on the flowline B the highest wall loss
flowline C was measured at 94.3%. Considering the manu-
was 19.1%, with the minimum remaining wall thickness of
facturing tolerance of 10% (see also Table 1), no corrosion
12.86 mm). Based on the findings of the two inspections (16
was concluded for both locations. This confirmed that the
months apart), the corrosion rates were estimated at 1.95
liner was intact and, therefore, the primary barrier against
mm/year for the location on the flowline A and 0.64 mm/
corrosion was still effective. It should be noted that the carbon
year for the location on the flowline B.
steel welds (see Figures 5a and 5b) were also inspected using
Figure 6: Corrosion maps from Inspection 1 (top picture) and Inspection 2 (bottom picture) for the Flowline A
60
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Figure 7: Corrosion maps from Inspection 1 (top picture) and Inspection 2 (bottom picture) for the Flowline B
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Figure 8: Corrosion maps for the verification locations scanned during Inspection 2 on the flowline A
(top picture) and flowline C (bottom picture)
62
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2.4 Fitness for Service Assessment
For the two locations with liner anomalies Level 1 and Level
service lives were estimated using the highest corrosion rate
2 assessment were completed in accordance with DNV-
estimated from the two inspections (1.95 mm/year).
RP-F101 Part B, using the WGK in-house software “IC-Finesse”.
The defect dimensions were sourced from the river bottom
The findings of the Level 1 and Level 2 assessments are sum-
profiles obtained during the inspection. To account for the
marised in Table 2. The Level 1 assessment confirmed that for
measurement error В±1 mm axial resolution (high resolution
both locations the defects were acceptable, and the Level 2
scan) was used for defect length, and В±0.25 mm depth
assessment enabled less conservative prediction of the re-
resolution was used for defect depth. The depth resolution
maining service lives. During the Level 2 assessment it was
was applied to the wall thickness readings reported in the
assumed that a uniform wall loss rate would occur going for-
river bottom profiles. For the Level 2 assessment the number
ward, at the estimated corrosion rate of 1.95 mm/year. It can
of increments was set at 20 (DNV-RP-F101 recommends
be seen that, when compared to the results of the Level 1
number of increments between 10 and 50). And, to account
assessment, the remaining service life obtained by the Level
for the worst case, the remaining
2 assessment for the location with the deepest defect improved by approximately 0.6 years (7 months).
Flowlines
Minimum Safe Operating Pressure, bar
Minimum allowable
wall thickness at
MAOP, mm
Remaining wall thickness to failure, mm
Remaining service life,
years
Level 1 Assessment
A
241
7.39
1.66
0.9
B
306
6.98
4.33
2.2
Level 2 Assessment
A
246
6.11
2.94
1.5
B
312
6.10
5.21
2.7
Table 2: Summary of Fitness for Service Assessment
The wall loss rates used for estimating the remaining service
be higher than that recorded in between the two inspec-
lives were based on the real wall thickness data. However,
tions. The results of the fitness for service assessment were
it was acknowledged that because galvanic corrosion was
used to plan the remedial works, and replacement of the
present, the remaining service lives could be less, because
flowline stalks with the damaged liner was carried out in
the corrosion rate during the remaining service period can
summer 2013.
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3. Summary and Conclusions
The case study presented in this paper is based on the ex-
If intact, polymer liner provides an effective barrier to miti-
perience from a North Sea asset, where polymer liner at two
gate the main internal corrosion mechanisms. Liner damage
spot locations on the water injection flowlines was damaged
may occur during remedial works, which will result in carbon
due to remedial works. This compromised the main barrier,
steel being exposed to internal corrosion, compromising the
exposing the carbon steel to general and localised corrosion
integrity of the flowline. If a polymer lined flowline was in-
with estimated rates of up to 1.95 mm/year.
The external UT inspections enabled information on the condition of the pipes at the
locations where the liner was damaged, also
enabling fitness for service assessment. The
any liner damage may not be detected if the period between the
installation or remedial works
and inspection is too short.
stalled in several parts or remedial works
were undertaken in the past, an external
wall thickness inspection is recommended
to confirm that no liner damage occurred.
And, because corrosion is the main indica-
information from the fitness for service assessment was used
tor of liner issues, any liner damage may not be detected if
to plan the remedial works. Targeted inspection of the veri-
the period between the installation or remedial works and
fication locations showed no corrosion and confirmed that
inspection is too short.
the liner was intact after 15 years of service.
Authors
Damir Tadjiev
Mark Murray
Bryce Stewart
Wood Group Kenny
Wood Group Kenny
Wood Group Kenny
Aberdeen AB10 1TN
Aberdeen AB10 1TN
Aberdeen AB10 1TN
United Kingdom
United Kingdom
United Kingdom
[email protected]
[email protected]
[email protected]
64
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STATS GROUP
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www.statsgroup.com
65
Research / Development / Technology
Designing onshore high-pressure gas pipelines against the
geohazard of earthquake-induced slope instabilities
Prodromos Psarropoulos, Andreas Antoniou
National Technical University Of Athens (NTUA), Greece
Abstract
During the next decades many onshore high-pressure gas
duced slope instability. Additionally, the paper refers to the
pipelines are expected to be constructed all over the world.
possible mitigation measures that may be adopted for the
Depending on the prevailing geomorphological and geo-
slope stabilization and the minimization of the permanent
logical conditions, the quantitative assessment of the geo-
ground deformations. Finally, the paper deals with the provi-
hazard of slope instability and the evaluation of the associ-
sions of seismic norms related to the seismic design of pipe-
ated risk for the pipeline are undoubtedly very important
lines, which are rather insufficient to cover all the aforemen-
issues of the pipeline design. Nevertheless, slope stability
tioned issues in detail. Through characteristic case studies
assessment in areas characterized by moderate or high
in earthquake-prone areas it is shown that, apart from en-
seismicity is much more demanding and challenging since
gineering judgment, reliable data and advanced modeling
many issues are directly or indirectly associated to a poten-
are required in order to obtain a realistic quantitative assess-
tial earthquake. The strong ground shaking during a seismic
ment on a case-by-case basis.
event and the nonlinear ground response may cause a slope
instability that will certainly impose permanent ground de-
1. Introduction
formations to the overlying pipeline, and consequently additional pipeline strain. The current paper aims to illustrate
In the following decades the increased demand for energy
the main topics of seismic slope-stability assessment that
worldwide will undoubtedly require the smooth and safe
have to be coped with for the proper design of onshore
transfer of natural gas at great distances. This process is ex-
high-pressure gas pipelines. In the first part of the paper,
pected to be performed mainly via high-pressure onshore
after a brief overview of the concepts of “limit-equilibrium”
(and/or offshore) pipelines and the associated facilities.
and “pseudo-static acceleration”, the available analytical and
Since many of the onshore pipelines are going to cross areas
numerical methods of seismic slope-stability assessment
with various geomorphological and geological conditions, a
are described in detail. Emphasis is also given on the second
variety of geohazards (such as soil erosion, karst phenome-
part of the study, which deals with the issue of soil-pipeline
na, slope instabilities, etc.) will potentially threaten the pipe-
interaction and the pipeline distress due to the permanent
line integrity and serviceability.
ground deformations that may be caused by earthquake-in
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Nevertheless, in many areas worldwide
that are characterized by moderate to
high seismicity, rupture of an active fault,
strong ground motion and the consequent ground failures during an earthquake will certainly cause earthquake-related geohazards (such as soil liquefaction
phenomena and/or earthquake-induced
slope instabilities), leading to an increase
of the pipeline distress and a decrease of
its safety margin.
As mentioned before, one of the main geohazards that has to be taken seriously into
account during the design of an onshore
Table 3: Figure 1(a): An aerial photograph showing great
high-pressure gas pipeline crossing hilly and mountainous
landslides caused by the 2008 Wenchuan earthquake
areas is the potential slope instabilities under static and seismic conditions. It is evident that in such areas various slope
Figure 1(b) shows a very destructive landslide that was trig-
instability phenomena (i.e. landslides, flows, rockfalls, etc.)
gered during the 1995 Kobe earthquake in Japan. Nikawa
may arise, while their severity will be substantially increased
landslide was one of the most devastating landslides directly
in the event of an earthquake.
related to the earthquake, since it destroyed many residential buildings and caused many fatalities (Sassa et al. 1996).
Depending on the way they have been formed, slopes may
be characterized as natural or artificial. The artificial slopes
are either embankments or cuts. Additionally, slopes may be
categorized to soil slopes and rock slopes, depending on the
geomaterials of the slope. However, due to the weathering
process and/or tectonic movements many rock slopes do
not consist of intact rock, but of rock mass which in the case
of existence of several random discontinuity planes has usually a soil behavior (from an engineering point of view). An
example of landslides of rock masses is presented in the fol-
Figure 1(b): Aerial photo of the Nikawa landslide
lowing figure, which shows the impact of the strong ground
after the 1995 Kobe earthquake
motion on slope stability in mountainous areas of southwest
China during the 2008 Wenchuan earthquake.
As shown in the following figure, the main types or soilslope instabilities are shallow or deep failures, debris flows or
earthflows, and creep phenomena, while the main types of
rock-slope instabilities are circular or planar failures, wedge
failures, toppling, and rockfalls, depending on the rock mass.
Figure 1(c):
Rock-slope /failure
on Lefkada
islandTechnology Journal - September 2014
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/ Development
Technology
Pipeline
67
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As shown in the sketch of Figure 3, the potential instabilities of a slope under static (and
seismic conditions) are expected to impose
permanent ground deformations to a pipeline
crossing the unstable area, causing thus additional pipeline distress. This distress may cause
unacceptable strains due to compression,
tension, and bending or even pipeline failure
depending on the circumstances. Note that
rockfalls is a special case of rock slope instability that does not impose permanent ground
deformations to the pipeline. In the case of an
above ground pipeline, the impact of a rockfall with large-volume rock boulders on the
pipeline is evident, while in the case of a buried pipeline, the rock boulders may damage
the pipeline either by penetration through the
backfill material or by excessive impact stress,
depending on the burial depth
Figure 2: Main types of instabilities of soil and rock
According to Varnes (1978), earthquake-induced landslides
may be classified into three broad categories: (a) disrupted
slides and falls, (b) coherent slides, and (c) lateral spreads
and flows. In the first case the soil or rock material in the slide
is sheared and distorted in a nearly random manner. The
slopes involved are usually steep and failures take place very
suddenly. Disrupted slides and falls include disrupted soil/
rock slides, soil/rock falls and soil/rock avalanches. Coherent
slides generally occur at deeper failure surfaces in moderate
Figure 3: Pipeline distress due to permanent ground
to steeply sloping ground and they involve rotational and
deformations caused by slope instability
translational failures of coherent soil and/or rock blocks.
These failures include rock/soil slumps, rock/soil block slides
and slow earth flows. They develop at slow to rapid velocities.
68
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Note that rockfalls is a special case of rock slope instability
Additionally, the paper refers to the possible mitigation mea-
that does not impose permanent ground deformations to
sures that may be adopted for the slope stabilization and
the pipeline. In the case of an above ground pipeline, the
the minimization of the permanent ground deformations.
impact of a rockfall with large-volume rock boulders on the
Finally, the paper deals with the provisions of seismic norms
pipeline is evident, while in the case of a buried pipeline,
related to the seismic design of pipelines, which are rather
the rock boulders may damage the pipeline either by pen-
insufficient to cover in detail all the aforementioned issues.
etration through the backfill material or by excessive impact
Through characteristic case studies in earthquake-prone ar-
stress, depending on the burial depth.
eas it is shown that, apart from engineering judgment, reliable data and advanced modeling are required in order to
Based on the aforementioned, the seismic design of any
obtain a realistic quantitative assessment on a case-by-case
onshore high-pressure gas pipeline should aim to eliminate
basis.
the probability of occurrence of a potential accident and its
consequences. This goal may be achieved through: (a) the
identification of the potentially unstable areas, (b) the quantification of the potential slope instability in terms of factors
2. Slope Stability Assessment
Static conditions
of safety and permanent ground deformations, (c) the real-
As mentioned before, since the pipelines are long structures,
istic verification of the pipeline integrity through soil-pipe-
their route is expected to cross regions of high risk of slope
line interaction analysis, and (d) the design of cost-effective
instabilities, where the main driving force under static condi-
mitigation measures (in case that the previous verification is
tions is gravity. Nevertheless, although there is a limited un-
not satisfied).
certainty in the intensity of the driving force, there are many
factors with great uncertainty that may affect the safety
Therefore, the current paper aims to illustrate the main top-
margins of a slope. Slope instability depends on the geomor-
ics of slope instability assessment that have to be coped with
phology, the geology, the geotechnical characteristics of the
for the proper design of onshore high-pressure gas pipelines. In the first part of the paper, after a brief overview of the concepts
of “limit-equilibrium” and “pseudo-static acceleration”, the available analytical and nu-
The seismic design of any onshore
high-pressure gas pipeline should
aim to eliminate the probability
of occurrence of a potential accident and its consequences.
geomaterial(s) in the slope (including the
ground surface cover) and the groundwater conditions. Consequently, after the
identification of the potentially unstable areas (during the execution of the geological
merical methods of slope stability assessment are described
geomaterial(s) in the slope (including the ground surface
in detail. Emphasis is given on the second part of the study,
cover) and the groundwater conditions. Consequently, after
which deals with the issue of soil-pipeline interaction and
the identification of the potentially unstable areas (during
the pipeline distress due to the permanent ground defor-
the execution of the geological study/survey or during the
mations that may be caused by earthquake-induced slope
initial pipeline routing), the geotechnical engineers have to
instability.
quantify the static slope stability, either in terms of factors of
safety and/or in terms of permanent ground deformations.
It has to be emphasized that the identification process includes only a qualitative assessment that is based on the experience and the judgment of geoscientists, and obviously
cannot quantify the safety margins of stability.
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The factor of safety of a soil slope may be estimated on the
The equation that calculates the factor of safety under static
basis of the simplistic concept of “limit-equilibrium” that as-
conditions is the following:
sumes a sliding of a failure mass along a potential slip planar
(or circular) surface and it represents the ratio of resistant
forces T (or moments) over the driving forces N (or moments)
along this surface (see Figure 4).
F
S
ST
=
T
=
N
(W cosОё ) tan П† + c
W sin Оё
H
sin Оё
(2)
where c and П† are the shear-strength parameters of the
geomaterial (i.e. cohesion and angle of friction, respectively). Combining equations (1) and (2), the following equation
derives:
F
S
ST
=
tan П†
2c sin ОІ
+
tan Оё О—Оі sin( ОІ в€’ Оё ) sin Оё
(3)
The critical angle of failure, Оёcr, (where sliding will take
place) corresponds to the minimum factor of safety. It has
to be mentioned that the aforementioned equations are valid under dry conditions, while groundwater existence in a
slope may have a great impact on the factor of safety since it
may decrease the resistant forces and/or increase the driving
Figure 4: Sketch showing the resistant forces T and driving
forces.
forces N (or moments) for a stability analysis of a soil slope
Note that in some cases of homogeneous or heterogeneous
under static conditions.
In the case of a homogeneous geomaterial and a planar failure surface, the weight of the sliding mass, W, is given by the
following simple equation:
1
sin( ОІ в€’ Оё )
)
W = ОіО— 2 (
2
sin ОІ в€’ sin Оё
where
Оі: the unit weight of the geomaterial
H: the height of the slope
ОІ: the angle of the slope
Оё: the angle of failure ( < ОІ )
70
weathered and jointed rock formations, the rock mass of
slope may be treated as material with equivalent shearstrength parameters (cohesion c and angle of friction П†).
In some slopes, where the estimation of permanent ground
deformations is required (in addition to the factor of safe-
(1)
ty), two-dimensional or even three-dimensional numerical
methods can be applied, such as the finite-element method (FEM) or the finite-difference method (FDM). Numerical
methods discretize the medium into a specific number of
elements and nodes, and they lead to the calculation of displacements by solving a system of algebraic equations (see
Figure 5).
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The numerical methods have high accuracy (achieved either
Seismic conditions
by the refinement of the mesh and/or by utilizing high-order
elements). Additionally, they have the capability of simulat-
Apart from gravity and groundwater, the most common trig-
ing random geometries and/or various geomaterials, while
gering mechanism for slope instability is earthquake load-
they can simulate the non-linear behavior of geomaterials.
ing. In earthquake-prone areas the risk of slope instability
Nevertheless, the application of a numerical method re-
is increased as a seismic event may add inertial loading to
quires experience since numerical modeling involves vari-
the existing driving forces, while in some cases earthquake
ous issues, such as the mesh generation, the boundary con-
shaking leads to a substantial reduction of the soil strength
ditions, and the non-linear behavior of geomaterials.
parameters. It is noted that the cause of this reduction is usually related to pore-pressure increase and soil-liquefaction
Although a very realistic simulation of the slope behavior
phenomena.
may theoretically be achieved by the numerical simulations,
there exist many uncertainties in the estimation of perma-
Seismic slope-stability assessment is performed with the
nent ground deformations since numerical methods should
application of methods which are grouped according to the
follow after a detailed geotechnical survey and the corre-
adopted mathematical model in three main categories:
sponding in situ and laboratory tests, which is not always
the case.
(a) Pseudo-static methods,
(b) Permanent-deformation methods
(also called as sliding-block methods), and
(c) Numerical methods.
Figure 5: Finite-element modeling of an artificial slope under static conditions:
typical results of contours of permanent ground deformations.
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Although the application of pseudo-static methods is based
The inertial forces acting on the sliding mass in the horizon-
on simplifying assumptions, they have prevailed in current
tal and in the vertical direction are denoted as WО±h and WО±v,
engineering practice because of the high complexity of more
respectively, where W is the weight of the sliding mass, and
elaborate numerical models which require the definition
О±h and О±v are the corresponding seismic coefficients. Note
of stress-strain soil response under seismic loading (i.e.
that seismic coefficients О±h and О±v are regarded as con-
constitutive models).
stants although in reality they are time-depended variables.
Additionally, the vertical coefficient is usually regarded as
The main issue raised in the pseudo-static methods is the
secondary due to its lower amplitude, its higher frequency
selection of the so-called “seismic coefficient”. The latter is
and the observed incoherency between the horizontal and
defined as the ratio of the constant seismic force acting on the
vertical motion.
potential failure surface divided by the weight of the failure
wedge. The approximation of a constant seismic coefficient
may become an erroneous selection since: (a) near the slopes
the role of topography effects is predominant; hence, the
magnitude and the frequency content of the acceleration
time history varies throughout the potential failure surface,
and (b) the time-varying nature of the dynamic response
indicates that severe loading lasts only instantly. The
conservatism of the method (arising from the negligence
of both spatial and time variation of the inertia forces) was
early recognized, and seismic coefficients calibrated to
acceptable level of displacements were proposed for slope
stability assessment. Modern guidelines for the evaluation of
seismic induced landslides, like the guidelines of California
Geological Survey (CGS, 2008) for evaluating and mitigating
seismic hazards, propose the dependence of the seismic
coefficient on the peak ground acceleration at the bedrock,
the distance from the seismic source and the acceptable
seismic displacements. The following figure shows the
resistant and driving forces (or moments) for a stability
Figure 6: Sketch showing the resistant and driving forces
(or moments) for a stability analysis of a soil slope under
pseudo-static conditions.
analysis of a soil slope under pseudo-static conditions.
In the case of a slope characterized by seismic coefficients О±h
and О±v, and a planar failure surface, the factor of safety under
seismic (i.e. pseudo-static) conditions, FSPS, is given by the
following expression:
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Permanent-deformation methods are pertinent modifica-
F
S
PS
=
F
S
ST
a
в€’ tan П† (О± h в€’ v )
tan Оё
О±h
+ О±v +1
tan Оё
tions of the popular Newmark’s sliding-block approach. This
approach is based on the fundamental assumption that sta-
(4)
bility may be established according to a simple model, which
consists of a rigid block on an inclined plane, and therefore
displacements are obtained by double integration of the
relative acceleration. Relative acceleration is the difference
where FSST is the corresponding factor of safety under stat-
between the applied and the critical (or yield) acceleration,
ic conditions, calculated by equation [3]. If the vertical exci-
where the latter refers to the value of the acceleration re-
tation is neglected, equation (4) is simplified to:
quired to approach incipient sliding state, i.e., factor of safety
equal to 1.0. The most influential assumption of this method
is the negligence of the flexibility of the sliding mass. Ever
F
S
PS
=
F
S
ST
в€’ tan П† (О± h )
О±h
+1
tan Оё
since Newmark’s pioneering study, two different approach-
(5)
es have been proposed to overcome this limitation: (a) the
decoupled procedure where the dynamic response of the
examined failure surface is calculated separately from the induced displacements, and (b) the coupled procedure where
Although the assumption of planar failure surface is quite
the dynamic response is considered simultaneously to the
simplistic and may be realistic only for geomaterials with
permanent displacement development by the direct solu-
low cohesion, judging from equations (3) and (5), it becomes
tion of the governing differential equations.
evident that for typical values of П† and typical values of ОІ
and Оё, О± high value of seismic coefficient О±h (i.e. greater than
Apart from the rigorous analysis of permanent deformation
0.1) may cause a great difference between the factor of safe-
methods, the ground deformations can be estimated by
ty under static conditions FSST and the corresponding factor
graphs or empirical formulas of the literature which are very
of safety under pseudo-static conditions FSPS, leading thus
useful for a rapid assessment of expected level of seismic dis-
to a substantial reduction of the safety margin of a slope.
placement of slopes. The next figure, developed by Makdisi
& Seed in 1978 shows the relationship between the seismic
In general, slopes that have a pseudo-static factor of safe-
displacement and the ratio Ac/Amax for various earthquake
ty greater than 1.0 can be considered as stable, while if the
magnitudes, M. Ac is the critical acceleration that corre-
pseudo-static analysis results in a factor of safety lower than
sponds to FSST = 1.0, while Amax is the peak ground accel-
1.0, the engineers can employ a permanent-deformation
eration.
method to determine the magnitude of the permanent
ground deformations of the slope.
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Although the application of pseudo-static methods is based
The inertial forces acting on the sliding mass in the horizon-
on simplifying assumptions, they have prevailed in current
tal and in the vertical direction are denoted as WО±h and WО±v,
engineering practice because of the high complexity of more
respectively, where W is the weight of the sliding mass, and
elaborate numerical models which require the definition
О±h and О±v are the corresponding seismic coefficients. Note
of stress-strain soil response under seismic loading (i.e.
that seismic coefficients О±h and О±v are regarded as con-
constitutive models).
stants although in reality they are time-depended variables.
Additionally, the vertical coefficient is usually regarded as
The main issue raised in the pseudo-static methods is the
secondary due to its lower amplitude, its higher frequency
selection of the so-called “seismic coefficient”. The latter is
and the observed incoherency between the horizontal and
defined as the ratio of the constant seismic force acting on the
vertical motion.
potential failure surface divided by the weight of the failure
wedge. The approximation of a constant seismic coefficient
may become an erroneous selection since: (a) near the slopes
the role of topography effects is predominant; hence, the
magnitude and the frequency content of the acceleration
time history varies throughout the potential failure surface,
and (b) the time-varying nature of the dynamic response
indicates that severe loading lasts only instantly. The
conservatism of the method (arising from the negligence
of both spatial and time variation of the inertia forces) was
early recognized, and seismic coefficients calibrated to
acceptable level of displacements were proposed for slope
Ac/Amax
stability assessment. Modern guidelines for the evaluation of
seismic induced landslides, like the guidelines of California
Geological Survey (CGS, 2008) for evaluating and mitigating
Figure 7: Seismic displacement (in cm) versus Ac/Amax for
seismic hazards, propose the dependence of the seismic
various levels of earthquake magnitude M
coefficient on the peak ground acceleration at the bedrock,
the distance from the seismic source and the acceptable
A well-known expression was developed by Ambraseys &
seismic displacements. The following figure shows the
Menu (5):
resistant and driving forces (or moments) for a stability
analysis of a soil slope under pseudo-static conditions.
2.53
пЈ®пЈ«
Ac пЈ¶
пЈ·пЈ·
log(d1 ) = 0.90 + log пЈЇпЈ¬пЈ¬1 в€’
пЈЇпЈ°пЈ­ Amax пЈё
пЈ« Ac пЈ¶
пЈ¬пЈ¬
пЈ·пЈ·
пЈ­ Amax пЈё
в€’1.09
пЈ№
пЈє + 00.30p
.30 p
пЈєпЈ»
where d1 is the permanent ground deformations in cm, and
пЈ±0
p=пЈІ
пЈі2.32
74
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for
for50 %
50
%
probability of exceedance.
for1%1%
for
Pipeline Technology Journal - September 2014
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Since in the case of an earthquake there will be several occur-
c) Calculated displacements greater than 1.0 m are very like-
rences where the earthquake-induced acceleration exceeds
ly to correspond to damaging slope movement, including
the critical acceleration, producing a sequence of displace-
possible catastrophic failure, and such slopes should be con-
ments, it is expected that the total displacement (i.e. the per-
sidered unstable.
manent ground deformation) will depend not only on the
amplitude of the strong ground motion (i.e. peak ground ac-
In the second case, determining whether deformations in
celeration), but on the duration and the frequency content
this range can be accommodated safely requires good en-
of the strong ground motion. Therefore, more sophisticated
gineering judgment that takes into account issues such as
formulas have recently been developed that are taking into
slope geometry and material properties.
account the peak ground velocity and the magnitude of the
earthquake as well.
Nevertheless, in the case of a structure being located on the
examined slope, the engineers should correlate the perma-
Finally, the seismic slope-stability assessment can be per-
nent ground deformations with the type of the structure, as
formed utilizing numerical methods, like the finite-element
well as its geometrical and mechanical properties. It is ev-
method or the finite-difference method. Depending on the
ident that different structures are expected to behave in a
desired accuracy and the available data, the analysis may be
different way under identical pattern of permanent ground
either dynamic with a seismic excitation applied as acceler-
deformation.
ation time history at the model base or pseudo-static with
equivalent inertial forces acting on each element. It is noted
3. Soil-Pipeline Interaction
that dynamic numerical analyses have similar advantages
and disadvantages with the corresponding static analyses
As mentioned before, in case of slope instability, there are
described in previous section.
many patterns of permanent ground deformation which depend on the local geological / geotechnical conditions. As
In any case, according to the guidelines of CGS referring to
depicted in Figure 3, a pipeline may cross the permanent
slope movements:
ground deformation zone in any arbitrary direction. Pipeline
verification against slope instability should take into account
a) Permanent ground deformations lower than 0.15 m are
that parallel crossing will lead to tension at the upper part
unlikely to correspond to serious slope movement.
of the zone and compression at the lower part of the zone,
while the perpendicular is expected to cause bending (see
b) In the 0.15 m to 1.0 m range, slope deformation may
Figures 8(a) & 8(b)).
be sufficient to cause serious ground cracking or enough
strength loss to result in continuing (post-seismic) ground
failure.
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Modern guidelines for the evaluation of seismic induced landslides, like the guidelines of California
Geological Survey (CGS, 2008) for evaluating and
mitigating seismic hazards, propose the dependence of the seismic coefficient on the peak ground
acceleration at the bedrock, the distance from the
seismic source and the acceptable seismic displacements. The following figure shows the resistant and
driving forces (or moments) for a stability analysis of
Figure 8: Pipeline distress due to permanent ground
deformations caused by slope instability: (a) pipeline
crossing parallel to the direction of slope movement, (b)
pipeline crossing perpendicular to the direction of slope
movement.
a soil slope under pseudo-static conditions. In the case of a
buried pipeline, the pipeline behaviour should be analyzed
as a typical soil-structure interaction (SSI) problem. The term
“structure” is used to describe the pipeline itself, while “soil”
represents either the native ground or the backfill, depending on the geotechnical conditions. The following sections
Although the application of pseudo-static methods is based
describe the basic issues of the aforementioned interaction
on simplifying assumptions, they have prevailed in current
and the required verifications of the pipeline integrity. The
engineering practice because of the high complexity of more
first section is mainly devoted to the calculation of the soil
elaborate numerical models which require the definition
spring values, while the rest describe the verification against
of stress-strain soil response under seismic loading (i.e.
slope instability that includes the estimation of the pipeline
constitutive models).
distress due to permanent ground deformations caused by
seismic slope instabilities.
The main issue raised in the pseudo-static methods is the
selection of the so-called “seismic coefficient”. The latter
Note that the verification of a high-pressure gas pipeline
is defined as the ratio of the constant seismic force acting
should take simultaneously into consideration the afore-
on the potential failure surface divided by the weight
mentioned earthquake-induced load (i.e. the permanent
of the failure wedge. The approximation of a constant
ground deformations) and the operational loading (due to
seismic coefficient may become an erroneous selection
gravity, internal pressure, and temperature difference) due
since: (a) near the slopes the role of topography effects is
to the nonlinear behaviour of the pipeline material (i.e. steel).
predominant; hence, the magnitude and the frequency
content of the acceleration time history varies throughout
According to modern norms, the evaluation of pipeline re-
the potential failure surface, and (b) the time-varying nature
sponse to slope instability requires numerical analyses that
of the dynamic response indicates that severe loading lasts
account for non-linear soil and pipeline behaviour. It is noted
only instantly. The conservatism of the method (arising from
that this specific approach is similar for all the rest cases of
the negligence of both spatial and time variation of the
earthquake-induced permanent ground deformations (e.g.
inertia forces) was early recognized, and seismic coefficients
faulting, soil liquefaction, etc.).
calibrated to acceptable level of displacements were
proposed for slope stability assessment.
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Figure 9: The four springs around the pipeline representing the soil compliance.
Typically, the soil compliance around the pipeline is usually
Given the available geological and the geotechnical surveys/
represented by four translational bilinear soil springs at all
studies, the soil springs can be categorized in various groups
directions. More specifically (a) axial soil springs, (b) lateral
along the pipeline route. Based on the data of these studies,
soil springs, (c) vertical uplift soil springs, and (d) vertical
soil spring forces F and the corresponding mobilizing soil
bearing soil springs (see Figures 9 and 10).
displacements Оґ can be calculated according to ALA (2002)
for the four soil springs around the pipe.
In case of unstable slopes identified along the pipeline route,
representative numerical models should be developed, taking into account the characteristics of the slope failure and
the geological / geotechnical data. The verification of the
pipeline against slope instability should be performed utilizing a finite-element tool. For this purpose, three-dimensional (3-D) models are recommended to be developed, considering the soil – pipeline interaction. The model could include
either beam or shell elements.
In the case of beam elements, a 3-D beam-on-nonlinear-Win-
Figure 10: Idealized representation of the
kler-foundation finite-element model (BNWF) can be utilized
bi-linear soil springs.
for the estimation of the pipeline response to permanent
ground deformation. In this model the pipeline can be simu-
Note that soil spring forces should generally be based on the
lated through beam elements resting on springs which rep-
native ground properties, besides the axial springs for which
resent the soil surrounding the pipe. A sketch of the specific
soil properties representative of the backfill should be used
model is presented in the following figure.
to compute the corresponding forces.
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77
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Figure 11: Sketch of the beam-element model
The nonlinear response of the soil (axial and transversal) is
simulated through the four bilinear springs (axial, transverse,
vertical-uplift, and vertical-bearing). Figure 12 depicts a
close-up of a pipeline beam-element model.
Note that apart from beam
elements, the pipeline can be
simulated through pipe elements which can incorporate
the effects of stressing due to
internal pressure and calculate the corresponding hoop
stresses and strains. In addition to the stresses and strains being calculated for the whole
e
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section through section integration, values can be provided
also for the section integration points shown in Figure 13.
While analyzing the pipeline for permanent ground defor-
In this way, it is possible to estimate simultaneously both
mation, it is assumed that the development of ground defor-
tensile and compressive stress/strain at every cross-section
mation is gradual. Hence, pseudo-static analysis is applied
along the pipeline. The nonlinear stress-strain relationship of
for pipelines subjected to permanent ground deformations.
the pipe material should be considered through a plasticity
The ground deformation (in this case due to slope instabili-
model, while large displacement effects should also be tak-
ty) is assigned at the fixed ends of the soil springs along the
en into account.
sliding mass. Since the analysis is static, the damping and inertia effect can be ignored.
78
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Figure 13: Pipe section points where the stresses
and strains should be calculated.
Figure 14: Detail of the 3D shell-element model and the
It is emphasized that the analysis should be conducted as-
surrounding soil springs.
suming that the pipe is fully operational (i.e. internal pressure and temperature difference). That means that the calculated maximum axial strain is attributed not only to the slope
instability, but to the operational loads as well.
In the case of shell-elements, the stress and strain concentrations are captured in a more accurate way. The total length
of the model should extensively cover the unstable area.
Similarly to the beam-model, the surrounding soil can also
be simulated with the bilinear springs described previously.
The pipeline section can be discretized along the periphery,
while springs are attached at all nodes in all directions. The
values of the springs are assumed to be a function of the
projected area of the cross section in the corresponding di-
Figure 15: Cross section of the 3D shell-element model and
rection. Internal pressure should be modelled as a uniform-
the surrounding soil springs.
ly distributed load on the internal face of all shell elements,
while the fault movement should be applied as an imposed
The following figure shows typical results of a high-pressure
displacement at the free ends of the soil springs in half of
gas pipeline subjected to permanent ground deformations.
the model.
Since the axial strains should be at an acceptable level, it becomes evident that if the calculated strains on the pipeline are
excessive, various mitigation measures should be adopted.
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Figure 16: Deformed shape and contours of axial strains of a pipeline subjected to
permanent ground deformations.
4. Mitigation Measures
Since in pseudo-static (and static) analyses the factor of
safety (FS) is defined as the ratio of the resistance over the
In areas where the pipeline distress due to slope instabilities
driving forces causing the instability, the stabilization of the
will be unacceptably excessive, the relocation of the pipe-
slope may be achieved by:
line to avoid the critical areas would be an option. However, since the pipeline relocation may be impractical or even
a) increasing the resistance using an embankment at the toe
impossible for various reasons, mitigation and/or protection
of the slope, a retaining structure (e.g. sheet pile wall, etc.), or
measures should be adopted aiming to eliminate or reduce
even soil improvement (usually performed by soil reinforce-
the imposed pipeline distress to acceptable levels. It is evi-
ment).
dent that the final geometrical and mechanical properties of
any adopted measure, along with its impact on the pipeline
b) reducing the cause of the instability (by changing the
distress, should be verified by detailed geotechnical inves-
slope inclination and/or lowering the groundwater level).
tigation and simulations on a case-by-case basis. Given the
special characteristics of the problematic area, the selection
As shown in the following figure, besides the static and
of any mitigation or protection measure should take into
pseudo-static analyses, the engineers should alternatively
consideration various parameters, such as environmental
(a) estimate the expected permanent ground deformations
impact, constructability, accessibility, cost, etc.
at the slopes, and (b) verify the pipeline against these defor-
.
mations.
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If the pipeline distress is excessive, there exist two ways to
At the most critical areas, where great permanent ground
proceed (apart from the rather unfavourable avoidance of
deformations are expected, a monitoring scheme has to be
the problematic area through relocation). The first is to stabi-
implemented. The monitoring scheme could include the fol-
lize the slope adopting one or more of the aforementioned
lowing:
stabilization measures. The second is to change the characteristics of the pipeline either by increasing the pipe wall
a) Instrumentation in order to measure constantly the per-
thickness or increasing the pipeline flexibility.
manent ground deformations (e.g. inclinometers, topographical sensors, etc).
It has to be emphasized that since any pipeline is capable
to withstand a certain level of permanent ground defor-
b) Installation of strain gauges (or even optic fibers) on the
mations, the adoption of stabilization measures based only
pipeline in order to measure the pipeline distress.
on the static and pseudo-static analyses (that ignore the
permanent ground deformations) is a-priori a conservative
c) Recording of the strong ground motion with accelerom-
approach, increasing thus the overall construction cost. Ad-
eters. The recording of strong ground motion is optional,
ditionally, despite the fact that the adoption of any slope
while instruments could be placed either on the ground sur-
stabilization measure will reduce the expected permanent
face, at the ground base, or at the rock outcrop.
ground deformations under seismic conditions, the minimization of the permanent ground deformations is directly
All the instruments should be digital in order to collect and
related to the cost.
transfer the data to the operator.
Figure 17: Flowchart showing the optimum procedure for the design of gas transmission projects (pipelines &
facilities) potentially subjected to permanent ground deformations.
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It is evident that a detailed emergency plan should have
where t and r are the thickness and radius of the pipe,
been developed in advance, according to which the gas
respectively. EN 1998-4 also defines two separate limit states:
transmission should be blocked and emergency mitigation
(a) the ultimate limit state that implies structural failure, and
measures should be taken after the exceedance of a certain
(b) the damage limit state that assures the structural integri-
predefined level of permanent ground deformations and/or
ty and a minimum operating level. In the ultimate limit state,
pipeline strains.
EN 1998-4 proposes the following expression for the calculation of the design seismic action, AEd:
Regarding rockfalls (which is a special case of rock-slope instability), apart from the stabilization of the potentially un-
AEd = ОіО™ AEk , where:
stable rock masses above the pipeline with various methods,
one could adopt: (a) an active method of pipeline protection
ОіО™ is the importance factor. Four importance classes are
with stoppers, barriers and/or wire fences to prevent any im-
defined:
pact of the rockfall on the pipeline, or (b) a passive method of
protection with an increased overburden or an overburden
•
Class I (low risk) : ОіО™ = 0.8
made of synthetic smooth material (such as corpuscles of
•
Class IО™ (medium risk) : ОіО™ = 1.0
expanded polystyrene) to protect the pipeline in case of an
•
Class IО™О™ (high risk) : ОіО™ = 1.2
impact. In any case, analyses are required to design the opti-
•
Class IV (exceptional risk) : ОіО™ = 1.6
Note that in order to perform any analysis and to propose
AEk is the reference seismic action (defined as peak
any mitigation/protection measure against rockfalls, a spe-
ground acceleration in EN1998-1).
mum mitigation measure, depending on the circumstances.
cial study of the expected rockfalls is required. The study
should include estimation of potential rockfall volume, rock
In damage limit state, a reduction factor v may be used,
mass properties, dip and dip orientation of joints, wedge or
which is equal to 0.5 for important classes I and II, and equal
planar failures, etc.
to 0.4 for classes III and IV. EN 1998-1, which defines the
seismic actions, recognizes that the seismic motion at the
5. Norm Provisions
ground surface is strongly influenced by the underlying soil
conditions. The ground conditions are categorized in five
According to EN1998-4, a buried pipeline distressed by the
general ground types and two special ground types accord-
permanent ground deformations due to slope instabilities
ing to the shear-wave velocity in the top 30m, VS,30, and/
shall be verified not to exceed the available ductility of the
or indicative values for the number of blows evaluated with
material in tension and not to buckle locally or globally in
the standard penetration test, NSPT, and the undrained co-
compression. The allowable tensile strain, Оµallow,tens, is 3%,
hesive resistance, cu. The general ground types range from
while the allowable compressive strain, Оµallow,comp, is giv-
rock with VS,30 > 800m/s (ground type A) to thick alluvium
en by the following expression:
layers over stiffer materials (ground type E), while in the case
of the two problematic ground types (S1 and S2) special am-
min { 1%; 20t/r (%) }
(6)
plification studies for the definition of the seismic action are
required.
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According to EN1998-1, the ground type influences directly
On the contrary, for important structures the topographic
or indirectly both the shape of the elastic response spectra
features of the area under examination should be taken into
Se (see Figure 18) and the peak ground acceleration. Peak
account by introducing the topographic amplification factor
ground acceleration is equal to:
ST which should be applied near the top of cliffs. ST is defined in Annex A of EN1998-5 and ranges between 1.0 and
agS (7),
1.4 depending on the inclination, the geometry, and the soil
conditions.
where: ag is the reference peak ground acceleration on type A
ground (i.e. rock). It is specified in the seismic zonation maps
According to EN1998, an alternative representation of the
of each country (i.e. National Annexes) and corresponds to
seismic action, essentially for nonlinear analysis purposes,
the reference return period for the no-collapse requirement,
could be a set of artificial, recorded or simulated acceler-
TNCR (which has a recommended value of 475 years). S is the
ograms, provided that they are scaled to the peak ground
soil factor that depends on the ground type and the type of
acceleration and match the design response spectrum for
the seismic action. As it was expected, soil factor S ranges
5% damping. Figure 19 shows the contours of maximum
from 1.0 in the case of rock up to 1.8 in the case of soft soil
horizontal acceleration that have been estimated during of
layers. It has to be underlined that, although EN1998-1 takes
a two-dimensional dynamic analysis of a slope. In such an
into account the soil stratigraphy, it has no specific provisions
analysis, the soil stratigraphy and the topography effects
for the potential geomorphic (valley) effects.
have realistically been taken into account.
Figure 18: The elastic response spectra proposed by EN 1998-1 for the five ground types (A, B, C, D, E) and the
two types of seismic action according to the magnitude MS.
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83
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Figure 19: Results of a two-dimensional dynamic analysis of a slope
(contours of maximum horizontal acceleration)
Note that in the case of important structures, such as
According to EN1998-5, the response of ground slopes to
high-pressure gas pipelines, the design ground acceleration
the design earthquake shall be calculated either by means
ag (or the design seismic action AEd) and the corresponding
of established methods of dynamic analysis, such as finite
spectral values should be evaluated for various hazard levels
elements or rigid-block models, or by simplified pseudo-
(return periods) by the performance of a detailed seismolog-
static methods. In modeling the mechanical behavior of the
ical study, while the impact of the local site conditions on
soil media, the softening of the response with increasing
the seismic motion of the ground surface can be estimat-
strain level, and the possible effects of pore-pressure
ed by an amplification study that will take into account not
increase under cyclic loading shall be taken into account.
only the soil stratigraphy, but the geomorphology and the
The stability verification may be carried out by means of
topography of the area under examination as well. In any
simplified pseudo¬¬-static methods where the surface
case it is recommended to compare the acceleration levels
topography and soil stratigraphy do not present very abrupt
derived from the amplification studies with the correspond-
irregularities.
ing values proposed by EN1998 and seismic zonation of the
National Annexes. If the amplification studies lead to lower
The design seismic inertia forces FH and FV acting on the
acceleration levels than those proposed by EN1998, it is rec-
ground mass, for the horizontal and vertical directions
ommended the EN1998 provisions to be applied in the pipe-
respectively, in pseudo-static analyses shall be taken as:
line seismic design.
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FH = 0.5О±SW
The frequency content of the seismic motion is essentially
FV = В±0.5FH if the ratio avg/ag is greater than 0.6
accounted for, but not the interaction of the dynamic re-
FV = В±0.33FH if the ratio avg/ag is not greater than 0.6
sponse and the slip displacement accumulation.
where О± is the ratio of the design ground acceleration on
6. Conclusions
type A ground, ag, to the acceleration of gravity g; avg is the
design ground acceleration in the vertical direction; ag is the
The current paper refers to the issue of earthquake-induced
design ground acceleration for type A ground; S is the soil
slope instabilities and their potential impact to high-pres-
parameter; W is the weight of the sliding mass.
sure gas pipelines. It is shown that the realistic assessment
of slope instability under seismic conditions, the simula-
A topographic amplification factor for ag shall be taken into
tion of the soil-pipeline interaction during the imposition
account. The only exception is the case where the pseu-
of permanent ground deformations, and the design of the
do-static method of analysis is used and deep seated land-
corresponding mitigation measures are crucial issues of the
slides are expected.
pipeline design that require apart from reliable input data,
engineering judgment and experience.
As far as the seismic slope stability assessment is concerned,
EN1998-5 allows the engineer to select among the different
mathematical models when abrupt irregularities in topog-
Authors
raphy and soil stratigraphy are not present, and mechanical
behavior of soil is not sensitive to cyclic loading (strength
Prodromos N. Psarropoulos
degradation or pore pressure increase). Moreover, EN1998-5
Structural & Geotechnical
proceeds to suggestions with respect to the limitations of
each one of the aforementioned simplified methods. Regarding the selection of the seismic coefficient, it is stated
to be assigned at the “least safe potential slip surface”, while
it principally corresponds to “the ultimate limit state beyond
Engineer, MSc, PhD,
School of Rural and Surveying
Engineering, NTUA, Greece
[email protected]
which unacceptably large permanent displacements of the
ground mass takes place”. Hence even though the definition
of the unacceptable displacements is not clearly stated, the
horizontal seismic coefficient is set to be equal to 50% of
peak acceleration at slope surface irrespectively of the depth
of the failure surface. Moreover, the serviceability limit state
Andreas Antoniou
Geotechnical Engineer, PhD,
School of Civil Engineering,
is suggested to be checked after permanent deformation
NTUA, Greece
analyses of rigid block models, with the application of re-
[email protected]
corded earthquake time histories at the ground surface.
Research / Development / Technology
Pipeline Technology Journal - September 2014
85
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Am Listholze 82
30177 Hannover, Germany
Tel:
+49 (0)511 90992-10
Fax: +49 (0)511 90992-69
URL: www.eitep.de
Terms of publication
Twice a year, next issue: May 2015
Paper deadline: April 15th 2015
Advert Deadline: April 30th 2015
1
All pictures are used under the creative commons
- or comparable - licence: http://creativecommons.org/licenses/bysa/3.0/
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Conferences / Seminars / Exhibitions
Save The Date
Pipeline Technology
Conference
2015
Pipeline
Technology
8-10 June 2010
Conference
Europe’s Leading Conference and Exhibition on New Pipeline Technologies
8-10 June 2015, Estrel Berlin, Berlin, Germany
Discussion during the opening session
88
Attendees enjoying the Dinner Inv
Conferences / Seminars / Exhibitions Pipeline Technology Journal - September 2014
Conferences / Seminars / Exhibitions
Review of the 9th Pipeline Technology Conference 2015 in Berlin
Delegates from 42 different nations travelled to Berlin for the 9th Pipeline Technology Conference (ptc) from 1214 May, in order to gather information from nearly 70 presentations on the latest trends in design, construction,
operation and maintenance of onshore and offshore pipelines. A new attendance record was set with over 420
participants.
Current issues in the spotlight like the South Stream Project and the security of European supply in the wake of the
current crisis in Ukraine were included in the program alongside new developments in the areas of inline inspection,
leak detection, corrosion protection, compressor stations and pumping stations, construction procedures, material
issues and integrity management.
The ptc is supported in terms of content by 10 trade associations and published worldwide via 20 media partners.
An exhibition featuring 41 companies which ran alongside the conference was the most popular spot at break times.
Particularly the many participants from international operating companies used the chance to gather information
and compare the latest developments from different suppliers. Two evening events and a number of post-conference workshops rounded off the 9th ptc.
The 10th Pipeline Technology Conference will take place from 8-10 June 2015 in Berlin. Main topics will include
“Challenging Pipelines” and “Offshore Technologies”. As in previous years, the papers presented at this year’s ptc will
be available online.
For more information visit www.pipeline-conference.com.
vitation “Boat Trip: Berlin at Night”
Attendees networking at the exhibition
Conferences / Seminars / Exhibitions Pipeline Technology Journal - September 2014
89
Conferences / Seminars / Exhibitions
Join next Pipeline Technology Seminar Middle East
in November 2014, Abu Dhabi.
After the success of this February seminar which has left positive marks, once again leading pipeline industry individuals will join the PTSME 2014 on the 16-17 of November 2014 in Abu Dhabi.
Coming together with global technical experts, the well experienced course director (former technical manager of EuropeВґs biggest oil and gas pipeline transportation companies) Mr. Heinz Watzka will be leading through all operational
challenges in the oil and gas pipeline industry.
The two-day seminar will highlight the industry’s advancements in technological development, major projects and
future outlook.
All aspects of corrosion protection, control and prevention as well as resulted Pipeline Life-cycle extension strategies
(including Pipeline Integrity Management Systems (PIMS)• Inline Inspection (ILI) • Airborne gas leakage detection •
Pipeline Safety• Cathodic corrosion protection and its additional utilization • Right of-Way monitoring and third party
interference prevention • Case Studies etc...) will be covered.
The last seminar saw international delegates coming from Italy, Germany, UAE, Qatar and Saudi Arabia to further their
experiences and knowledge on the above mentioned topics.
For registration kindly visit the following website : www.pipeline-seminar.com
90
Conferences / Seminars / Exhibitions Pipeline Technology Journal - September 2014
Conferences / Seminars / Exhibitions
Some impressions from the Pipeline Technology seminar in February 2014 in Dubai
Picture by Nepenthes 1
Conferences / Seminars / Exhibitions Pipeline Technology Journal - September 2014
91
В© The government of Kuwait
Conferences / Seminars / Exhibitions
Kuwait
The Kuwait Towers - landmark and symbol of modern Kuwait
Picture by Lokantha 1
The countries GDP rose above 150 Billion $ in 2012
Picture by Ulrichulrich 1
92
Kuwait holds 10% of the worlds crude oil reserves.
Estimated reserves: 104 billion barrels
Conferences / Seminars / Exhibitions Pipeline Technology Journal - September 2014
Conferences / Seminars / Exhibitions
the next hub
in the Middle East
Picture by Mohdalg 1
Facts & Figures about Kuwait
•
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Full name: The State of Kuwait
Population: 2.9 million (UN, 2012)
Capital: Kuwait
Area: 17,818 sq km (6,880 sq miles)
Major language: Arabic
Monetary unit: 1 Dinar = 1000 fils
Main exports: Oil
GNI per capita: US $48,900 (World Bank, 2010)
GDP (PPP): $151.0 billion
5.1% growth
0.8% 5-year compound annual growth
$39,889 per capita
Unemployment:2.1%
Inflation (CPI):2.9%
FDI Inflow:$1.9 billion
Next Infrastructure Middle East 2015 in Kuwait.
More information shortly under the following website:
www.infrastructuremiddleeast.com
Conferences / Seminars / Exhibitions Pipeline Technology Journal - September 2014
93
Conferences / Seminars / Exhibitions
International infrastructure and pipeline events 2014/2015
Pipeline Technology
Conference
2015
Pipeline
Technology
Conference
2010
8-10 June
2015
Europe’s Leading Conference and Exhibition on New
Pipeline Technologies, taking place at the Estrel Berlin,
Berlin, Germany
www.pipeline-conference.com
PTJ covers reports about research, industry and practice,
presentation of innovative concepts and technologies
abd special reports about pipeline safety.
ptj will be sent to more than 15.000 international decision
makers and experts of the pipeline industry.
Next Issue:
May 2015
Pipeline Technology Seminar
(Middle East) in Abu Dhabi
16-17 November 2014
The 2-day Pipeline Technology Seminar (Middle East) gives
detailed information about well-approved strategies for a
failure-free and economic operation and maintenance of
high-pressure oil, gas and water pipeline systems.
www.pipeline-journal.com
Infrastructure Middle East
Kuwait, 2015
to be announced
www.pipeline-seminar.com
More information shortly under the following website:
http://www.infrastructuremiddleeast.com/
94
Conferences / Seminars / Exhibitions Pipeline Technology Journal - September 2014
Conferences / Seminars / Exhibitions
LISTEN WITH YOUR EYES
A new Generation
of Leak Detection Pigs.
Reliable performance - easy to use.
GOTTSBERG Leak Detection GmbH & Co. KG . Am Knick 20 . 22113 Oststeinbek . Germany
www.leak-detection.de . [email protected] . Fon +49 40 71 48 66 66 . Fax +49 40 71 48 66 77
Don’t miss an issue
Reach more than 15,000
top managers, engineers,
supervisory personnel
from oil and gas as well as
pipeline industry.
To advertise please contact :
Rana Alnasir-Boulos
Phone: +49 (0)511 90992-20
E-Mail: [email protected]
Offical Publication for
Pipeline Technolog
Conference 2010
Terms of publication
Twice a year, next issue: May 2015
Paper deadline: April 15th 2015
Advert Deadline: April 30th 2015
Conferences / Seminars / Exhibitions Pipeline Technology Journal - September 2014
95