premium digest april2011
TRANSCRIPT
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APRIL 2011
Ckey PRojects
3 Nordeuropische Erdgasleitung (NEL) Pipeline
stANDARDs
6 Qualifying pipe and coating manufacturers:providing solutions for pipe mills and coating yards
to demonstrate and document their capabilities
tecHNIcAL
8 Construction of a tunnel and other challenges forthe Gasduc-3 pipeline in Brazil
14 Development of an in-line ultrasonic inspection toolfor detection of pinhole-type defects in duplex-steelpipelines
NeWs WRAP
23 April 2011 News Wrap
A summary of the latest pipeline news from aroundthe world
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introdUCtion
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to whom GSP has provided permission.
www.pipelinesinternational.com
tIm tHomPsoN
sales manager
mIcHeLLe cRoss
design manager
LyNsDIe meWett
associate editor
DAvID eNtRINGeR
sales representative
joHN tIRAtsoo
editor-in-chief
scott PeARce
product manager
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Pipelines International Digestis the international oil and gas pipeline industrys foremost in-depth source of information about this
important and expanding sector, publishing high-quality papers covering the latest technology and reviews of the pipeline industry
worldwide.
Brought to you by John Tiratsoo and the rest of the team at Great Southern Press,Pipelines International Digestprovides a monthly
update of papers covering all areas of the industry from technical papers to key projects, and engineering and construction issues,
and environmental, regulatory, legal and nancial issues.
Subscribers toPipelines International Premium are provided with full access to all these features, as well as a searchable database of
both completed and current projects, and the hard-copy magazinePipelines International.
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key ProjeCts
The 440 km NEL Pipeline is part of a series of pipelines
currently being constructed to transport gas from Russia
to Europe to meet its increasing demand for energy.
The Nord Stream Pipeline, which will run from Vyborg in
Russia more than 1,220 km across the Baltic Sea to Greifswald
in Germany, comprises two parallel pipelines which are
being constructed in two phases. Over 1,000 km of Line 1 had
been laid by the end of February 2011 and pipelaying works
have already been completed at the landfalls for Line 2. Gas
deliveries from Line 1 will begin before the end of 2011. Ina second project phase, capacity will be doubled with the
construction of a parallel pipeline, which is scheduled to be
commissioned in 2012.
To carry away the 55 Bcm/per year of gas that Nord Stream
will bring to Europe, two onshore pipelines are being
constructed; the OPAL and NEL pipelines.
Whereas the OPAL Pipeline runs from the Nord Stream
landfall at Greifswald southward to the Czech Republic, the
NELs route extends from Greifswald, past Schwerin and
Hamburg, to Rehden, Lower Saxony, just south of Bremen.
The NEL Pipeline will not only secure the supply of gas to
Europe by providing additional transport capacities but, inconjunction with OPAL and Nord Stream, it will also make
Europes natural gas system more flexible.
ordeuropische
rdgasleitung (L) PipelineConstruction has commenced on the 440 km Nordeuropische Erdgasleitung (NEL) Pipeline one of thelargest pipeline projects in Germany today which will ensure Europes energy security in the long term.
Nacap workers establishing the pipeline stock pile and bending area.
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key ProjeCts
The pipeline will be able to transport about 20 Bcm/per year
of gas and is intended to transport Nord Stream gas produced to
customers in Germany, Denmark, the Netherlands, Belgium and
the UK.
Constructing the pipelineNacap has been awarded a contract to construct a 62 km section
of the pipeline in Lower Saxony.
The company has commenced activity on this section of the
pipeline. Current activity includes:
Safety inductions;
Mobilisation to site;
Establishment of pipeline stockpile and bending area;
Two bending devices in transit;
Right-of-way preparation and topsoil stripping;
Preparation of bending lists for bending; and, Landowner and authorities liaison.
Nacap has said that this large diameter, high-pressure
pipeline must be constructed with the minimum possible soil
Cranes unload the bending machine.
Bending machine is in place.
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key ProjeCts
disturbance. This means that sheet piling will need to be placed
on 12 km of the pipeline route and drainage measures will be
needed on large parts of the section. A considerable number of
existing pipelines will also need to be taken into account, and
many crossings will need to be completed.
Nacap spoke withPipelines International Digestabout the
challenges of the project.
Dewatering will be a signicant challenge on the project
as 80 per cent of the pipeline route needs to be dewatered.It will require proper work preparation, close contact and
communication with water authorities, monitoring of water table
and the shortest construction times per section to minimise water
table lowering period.
Another challenge identied by the Nacap team was the
peat areas which will require excavation between sheet piling,
increased work preparation and specic safety inductions for
individuals working in this terrain.
The project is being executed by the German and Dutch energy
companies Wingas, E.ON Ruhrgas and Gasunie and is scheduledto be brought online in 2012.
Nacaps bending machine, ready to be transported to site.
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standards
The oshore market demands rigorous quality such as that
set by recognised standards such as DNV Oshore Standard
DNV-OS-F101 Submarine Pipeline Systems. A new support
to the pipeline market is a DNV service that provides solutions forpipe mills and coating yards to demonstrate and document their
capability to manufacture high quality linepipe. The standard here
isDNV-OSS-313 Qualifcation o Pipe Mills and Coating Yards.
The development of the oshore and subsea market has
amplied the need to have properly qualied and experienced
suppliers of linepipe and linepipe coating. Indeed, the strict
requirements for subsea linepipe are met by only a limited
number of pipe mills around the world; procedures, equipment,
and personnel must all be at a high level.
A qualication according to the new DNV-OSS-313 includes a
thorough review of the essential manufacturing procedures, in
addition to monitoring and witnessing of production and testing
by DNV specialists. To obtain a qualication, manufacturers mustcarry out a trial production and perform extensive qualication
testing. DNV will write detailed reports on all activities and, upon
successful completion of the production and testing, a Statement
of Compliance will be issued.
Advantages throughout the value chainThe new service meets a requested need from both
manufacturers and purchasers, and will give benets to most
of the value chain for subsea pipelines. A DNV Statement of
Compliance means that there will be less concerns with the
production of the most capital-intensive and time-consuming
item the linepipe. In addition, the time required for start-upof production will be reduced, since all essential procedures
already meet the requirements, limiting the need for additional
clarication. A DNV qualication of the main manufacturers
means that the pipeline project will progress faster and with
less risk, which ts in with the current drive from the petroleumcompanies to fast-track projects.
A pipe mill or coating yard can carry out a qualication in
order to prove its capabilities, and ensure that the procedures,
equipment, and personnel satisfy all the requirements for
production. DNV will issue a Statement of Compliance upon
successful completion of the qualication project, and the
statement can be used in lieu of project references and for
marketing purposes. The oshore and subsea industry can be
somewhat conservative, and new entrants often have a long
process to be accepted by potential clients. The new qualication
service will make market acceptance quicker.
On the other hand, clients can set a DNV qualication asa condition for entering the tender phase of a project, which
means that the Statement of Compliance is a ticket-to-trade.
Note that in the technical requirements in DNV-OS-F101
Qualifying pipe and coating
manufacturers: providing solutionsfor pipe mills and coating yards todemonstrate and document theircapabilitiesBy Morten Solnrdal and Bjrn-Andreas Hugaas, Det Norske Veritas (DNV), Hvik, Norway
The market for offshore pipelines continues to grow and evolve. New players are entering and customers have increasedtheir focus on product quality, project schedule, and reduction of risks. Requests from the industry have motivated DNVto launch a qualication service of pipe mills and coating yards. This article describes how this service enables pipemills and coating yards to document their capabilities toward the offshore market.
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standards
and DNV-RP-F106, it is not required to use materials from
manufacturers qualied by DNV.
DNV will provide proactive feedback and guidance during the
qualication, as far as possible without violating its status as an
independent, third-party agent. The qualication process is also
an opportunity to bring mill procedures and practices up to an
international quality level.
Both pipeline operators and contractors will benet from this
service. A thorough review of key procedures and witnessing
of production and testing by DNV specialists will clearly
document which manufacturers are capable of producing high-
quality linepipe. This objective and independent assessment of
manufacturers can be valuable in the early phases of a pipeline
project, when potential suppliers are contacted and the tender
process started.
Detailed description of OSS-313The main phases in DNVs pipe mill and coating yard
qualication programme are: Initiation
Document review of manufacturing procedures
Trial production monitoring
Review of trial production results
DNV Verication Report
Statement of Compliance.
The scope of work will be established in co-operation with the
pipe mill/coating yard and DNVs specialist resources. The extent
of qualication (one or several steel grades, diameters, wall
thicknesses, coating systems, etc.) must be determined.
The pipe mill/coating yard will dene the relevant parameters
such as diameter, wall thickness, steel grade, coating system,design temperatures, and supplementary requirements. If the aim
is a specic project, it is recommended that the parameters dened
by the potential client are used. If the aim is to obtain a Statement
of Compliance for general marketing purposes, the parameters
should reect the mills capabilities and intended market.
The qualication can be carried out based on a clients
specication, provided that DNV-OS-F101 is used as the governing
standard. The relevant documents and manufacturing procedures
will be reviewed and commented upon by specialists with in-
depth knowledge of pipe manufacture, coating application, non-
destructive testing (NDT), welding, and material testing.
The pipe mill and/or coating yard will be responsible for
conducting a trial production, according to the ManufacturingProcedure Qualication Test (MPQT)/PQT requirements in DNV-
OS-F101/DNV-RP-F106. DNV specialists in pipe manufacture,
NDT, and linepipe coating will be present during the trial
production, and will assess the quality of the equipment, the
knowledge and experience of the production personnel, and the
implementation of the accepted procedures. A detailed site visit
report will be issued after each site visit.
The pipe mill or coating yard will issue a qualication
report, in which the results from the qualication process are
presented. This report will be submitted to DNV for review and
acceptance. DNV will issue a Verication Report, in which all
relevant activities are summarised. In addition to ensuring that
all the requirements in DNV-OS-F101 are met, DNV will give a
general assessment of the pipe mill or coating yard and provide
recommendations that could potentially help the mill to be better
prepared for the international market.
A Statement of Compliance will be issued upon successful
completion of all the stages in the qualication process. With the
Statement of Compliance, DNV conrms that the pipe mill has
fully met all the relevant requirements of DNV-OS-F101 and/or
DNV-RP-F106.
Maintaining a unique quality worldwideAs an independent partner, DNV will be providing the same
level of quality and technical requirements worldwide. Internal
procedures, personnel training, and peer review ensure that
products are equivalent in all locations.
One department in DNV will be responsible for theworldwide implementation of DNV-OSS-313, in order to ensure
that an equal level of document review and monitoring is
carried out for all projects. At the same time, it is important
to DNV that as much as possible of the activity, project
responsibility, and client contact is located in the local units
and facilities.
Market in development requires qualied playersThe traditional suppliers of linepipe according to DNV-
OS-F101 are from Germany, UK, and Japan, with a few
additional companies in Italy and Mexico. The last 10 years
have seen large changes in the steel industry, with severalnew countries developing a fast-growing steel manufacturing
sector. One product is steel pipe for the onshore market, but it
has proven difficult for many companies to enter the market
for subsea pipelines.
DNV has carried out qualication projects for four dierent
Russian pipe mills over the last three years. Russia has had a
strong metallurgical industry since the industrial revolution took
hold in the country. The vast hydrocarbon reserves of Russia
have to a large extent been transported by onshore pipelines to
internal and external markets, and the pipes have been delivered
by domestic suppliers. Since 2000, several of the major Russian
pipe mills have upgraded their equipment, and sometimes built
completely new production lines, geared toward meeting therequirements for submarine pipelines. Still, without previous
project experience it has proved dicult to get acceptance in the
oshore petroleum market.
DNV has carried out qualification projects for four different
Russian pipe mills over the last three years, covering both
linepipe production and coating application. Several
Statements of Compliance have been issued, and this has
proven important for the pipe mills in signing contracts with
international clients.
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This article describes the construction of the Cabinas-Reduc-3 gas pipeline (Gasduc-3) and aims to show how theplanning and implementation of the project took place, taking account of the construction difculties while meeting theneeds of the expanding Brazilian natural gas market.
Construction of a tunnel andother challenges for the Gasduc-3
pipeline in Brazil
Petrobras completed the construction of the Cabinas-
Reduc-3 (Gasduc-3) gas pipeline in 2010, one of themost complex land pipeline projects ever accomplished
in Brazil. The pipelines 38 inch diameter provided a number
of difficulties which had to be overcome. One of these was a
tunnel that was built for the gas pipeline, an initiative that
provided technical, safety, and environmental benefits, but
which also provided one of the main physical challenges of
the project.
The total investment in Gasduc-3 was approximately
$US1.4 billion, including construction management, project and
environmental licensing, and payments to landowners for the
right-of-way. Gasduc-3 was completed in 15 months, achieving
the expectations of the client and the company, and fullling itsfundamental role in improving natural gas supply to the Brazilian
consumer market.
Main features of the project
The right-of-wayGasduc-3 is located in the State of Rio de Janeiro (see Figure
1). It begins at the pig-launch area in the Cabinas compression
station in Maca, and follows the right-of-way (ROW) of the
existing Osduc-2 pipeline to kilometer point (KP) 100. From this
point on, the gas pipeline diverts from the oil pipelines route,
passes through a tunnel under the Santana Mountain Range, and
rejoins the Osduc-2 again at KP 125, continuing from there to the
Campos Elseos terminal at the Duque de Caxias renery. The
pipelines 179 km route pass through the municipalities of Maca,
Rio das Ostras, Casimiro de Abreu, Silva Jardim, Cachoeiras de
Macacu, and Guapimirim.As part of the strategy to meet the projects 15-month deadline
for pipeline construction and commissioning, two simultaneous
By Celso A dOliveira, Andr N Teixeira, Fabiano C Rodrigues, Marcos S Matos, Jorge F P Coelho,and Paulo Marcelo F Montes, Petrobras, Rio de Janeiro, Brazil
teChniCal
Figure 1: Gasduc-3 (red line) and Brazils pipeline network.
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and independent work fronts called packages were eected.
Package 1 covered approximately 104 km, linking the Cabinasstation to shut down valve 12 (SDV-12), between Maca and
Cachoeiras de Macacu. Package 2, between Cachoeiras de Macacu
and Duque de Caxias, is about 75 km in length from SDV-12 to the
pipelines manifold at Campos Elseos.
The pipeline route comprises new, as well as existing, sections
of ROW; in particular, Package 2 required the implementation of
two new ROWs.
A striking feature of the pipeline route is the relationship with
the communities aected by the project, located both in rural areas
and those with of high population densities. Intensive negotiations
allowed over 1,300 properties to be crossed by the pipeline,
and involved payment of appropriate nancial reparations.
Furthermore, during the pipelines construction, a number of social
responsibility and environmental education programmes were
regularly held, focusing on informing the general public of the
projects background, rationale, and progress.
Technical dataThe 38 inch diameter Gasduc-3 has the largest diameter of
any constructed by Petrobras in the last 30 years, and has ow
capacity of 40 MMcm/d, and a maximum operating and design
pressure of 100 kilogram force per square centimetre (kgf/sq cm).
The project also included construction of a 3,758 m long tunnelin the Cachoeiras de Macacu mountain region. Table 1 shows the
main operational details of the pipeline.
The carbon steel pipes used for Gasduc-3 have a nominal
diameter of 38 inches and were manufactured to API 5LX7 (Figure
2). The pipes have a triple-layer extruded polyethylene coating;
pipe thicknesses are in three sizes, giving rise to varying weights
for each pipe length:
0.625 inch wall thickness pipe: weight 4,777 kg
0.750 inch wall thickness pipe: weight 5,479 kg
0.875 inch wall thickness pipe: weight 6,348 kg
The pipelines welded joints are externally covered with
thermally-applied eld-joint coatings. Internally, the joints havenot been coated because internal corrosion is not expected due
to the characteristics of the natural gas which the pipeline will
transport. However, two sets of corrosion samplers were installed
Project timeline
9 June 2008: contract signed for construction of the tunnel
8 August 2008: contract signed for construction of the
pipeline
18 August 2009: completion of tunnel excavation
19 September 2009: start of mechanical roller assembly
inside the tunnel
5 November 2009: completion of construction of the pipe
inside the tunnel
28 January 2010: completion of inertisation of the pipeline
4 February 2010: start of gas lling of the pipeline.
Flow
(106
cubic metres/d*)
normal 440
maximum 40
minimum 4
Pressure (kgf/sq cm) normal 65100
maximum 100
project 100
Temperature (C) operation 4.345
project 055
* ow reference conditions: 1 atm and 20 Celsius
Table 1: Pipeline parameters.
Figure 2: Concrete-coating and pipe-bending yard.
Figure 3: Pipe stringing.
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along the pipeline, each consisting of two samplers for weightloss and two for electric resistance. These are located in existing
installations along the ROW.
As an additional protection against external corrosion,
impressed-current cathodic protection has been installed along
the pipeline, together with electrical insulation joints at the
Cabinas Station and on arrival at the manifold at Campos
Elseos, designed to prevent leakage of the c-p current into the
above-ground sections of the pipeline.
For operational safety of the pipeline, the project included the
installation of 11 ball valves for isolation, designed to reduce the
inventory of gas released into the atmosphere in the event of a
leak. The valves automated actuators are designed to close in
cases of both low pressure and rapid pressure drop. The valvesare buried and are tted with 12 inch nominal diameter by-passes
for use in the case of depressurising a pipeline section.
Two pig trap areas were built for installation of the launchers
and receivers, used for cleaning and inspection of the pipeline.
At both ends ow meters were installed for operational control.
All the block valves installed in for the pig launcher and receiver
(SDVs and XVs) are remotely monitored remotely; two of the
intermediate SDVs are also remotely monitored, and have closing
commands triggered by the SCADA system.
The project also includes two otakes at existing city gates:
the rst, close to KP 12.9, provides gas for the Maca Merchant
and Norte Fluminense, and the other, near KP 140.5, feedsGuapimirim. The interconnection of the pipeline at the city gates
was done by hot tapping, without interruption of gas supplies
from the neighbouring Gasduc-2.
Construction aspectsIn addition to manual welding, automatic welding was used.Although, traditionally, this method has not commonly been
used in Brazil, due to the topography, for Gasduc-3 this method
was used at a large scale and successfully increased production
and reduced repairs. All the welding procedures used whether
manual, semi-automatic, or automatic required qualication
of the welders to Level 2. All the welds were inspected by
radiography or ultrasound, following the qualied procedure,
ensuring their quality and traceability. The semi-automatic and
automatic welded joints were inspected by automated ultrasound.
Logistic challenges
The pipelines characteristics of large diameter, wall thickness,and weight, raised a number of major challenges for the project,
and made the Gasduc-3 one of the most complex onshore
pipeline projects in Brazil (gures 47). The transportation of
pipes required a large number of trips due to load limits of the
trucks, which could carry a maximum of four pipes of the lowest
wall thickness. The distance between the pipe-manufacturing
plant, in So Paulo, and the storage sites for the project, in the
municipalities of Silva Jardim and Itabora, also hampered the
logistics. In total, about 15,000 individual pipes were transported
for Gasduc-3.
A considerable number of the pipes required concrete coating,
which both increased the logistics and handling challenges andalso reduced the number that could be transported on each truck
to one at a time due to the increased weight of up to 16 tonnes
each pipe. This also required more-robust equipment, consistent
Figure 4: Pipe stringing on a steep slope. Figure 5: Pipelaying on a steep slope, where equipment anchoring
was required.
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with the size of the project, than was readily available in the local
market. Accordingly, sidebooms and pipe-bending machines
had to be imported to meet the projects specic equipment
requirements.
Special worksThe route of Gasduc-3 is characterised by extensive
mountainous areas where steep slopes necessitated anchoring of
the construction equipment. The many changes in elevation and
the sinuous slopes also necessitated hot bending of the pipes for
places where the curvatures exceeded 18. This was undertaken
by a specialised company; unlike cold bending which could be
done on site using bending machines, the nine hot bends (the
smallest of which was 28 on a 0.875 inch wall thickness pipe,
with the largest being 56) had to be done o site.
The ROW also had long stretches of wetlands and oodplains,
totalling nearly 80 km in length. Seventy-three river crossings
were required, undertaken using various techniques including
horizontal- directional drilling (HDD). Among the main rivercrossings, those of the Maca, So Joo, Macacu, Suru, and
Estrela rivers can be highlighted (see gures 8 and 9).
Two HDDs were required for the project, in which the pilot
hole was enlarged to 54 inch diameter to allow the pipe string
to be pulled through. For the HDD of the Maca River and the
neighbouring Virgem Santa canal, the trajectory of the pipeline to
cross both waterways at up the 14 m depth was formed by
61 pipes, making a total length of 745 m and a total pullback
weight of 335 tonnes. A further consideration of this crossing was
that it had to be made near the crossing of the Gaduc-1 pipeline,
which remained in operation throughout.
The HDD crossing under the Pirineus and So Joo Rivers, and
the Pirineus highway, required 770 m of pipe weighing around
346 tonnes; 240 m of this drill was in rock. The pipeline route in
general incorporated considerable amounts of rock, and over
18,000 cubic metres of rock excavation was undertaken with the
use of either explosives or hydraulic breakers.
There were also 56 railway, road (municipal, state, and federal),
and existing pipeline crossings.
SCADA systemThe Gasduc-3 has a centralised SCADA system. The pipeline
and its facilities are operated from pipeline operator Transpetros
master station. While the master station controls supervision,
control, and co-ordination of all operations for the pipeline, thereare also remote stations at the pig launch and receive traps.
The pipeline is connected to the existing data systems at
the Cabinas, Campos Elseos, and Silva Jardim stations. For
communication between local and the master stations, bre-
optic cable has been installed in the same ROW as the pipeline.
The bre-optic cable carries all communication, monitoring, and
control communications for the pipeline, and links the equipment
installed in the remote control rooms and telecommunication
stations with the pipeline-operators National Center for Control
and Operations (CNCO) in Rio de Janeiro, completing the Gasduc-
3s automated control system.
The bre-optic cable system is composed of two high-densitypolyethylene (HDPE) pipes, each approximately 105 km long,
containing the 36 bre-optical cable. There are 30 junction
boxes along the route and three access terminals, one at the
Figure 6: Pipe lowering-in.
Figure 7: Pushing the pipeline in a wetland area.
Figure 8: Pushing the pipeline during HDD.
Figure 9: Pipe arrival at the HDD o the Pirineus and So Joo Rivers.
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launch trap, one at SDV-10, and another at SDV-12; there are also
four panels at valves 7, 8, and 11 along the pipeline. A 2.5 square
millimetre electric cable is buried alongside the HDPE pipe to
provide an intervention alarm system.
The Gasduc-3 tunnelPetrobras chose to construct a tunnel for the pipeline under
Santana Mountain, nearby the town of Cachoeiras de Macacu, to
enhance construction eciency and safety, with the important
benet to preservation of the environment along that section of
the pipeline route (gures 10 and 11).
The arched-rectangular section tunnels dimensions are length3,758 m, height 6.2 m, and width 7.2 m; 150,000 cubic metres
of material were excavated, following around 1,200 controlled
detonations. The tunnel has been designed to accommodate four
other pipelines with diameters of 28 inches.
The tunnel construction cost $US81 million, and was
constructed on two simultaneous and independent fronts
working 24 hours a day, seven days a week. To achieve this, eight
teams were required, four for each excavation front, working
in shifts; a total of 795 workers were involved. The tunnel was
excavated using the conventional drill-and-blast method for the
rock sections, and the New Austrian Tunnelling Method (NATM)
for the sections in soil or variable rock.For assembly of the pipeline inside the tunnel, a new
technology developed by Liderroll was employed which
allowed the pipe joints to be welded outside the tunnel and
pulled-in on rollers set up on the tunnel oor (Figure 12). This
ingenious solution removed the requirement for the pipe to be
welded inside the tunnel, which would have been dicult and
dangerous due to restrictions on space and ventilation.
For this process, the pipe column was aligned and welded
outside the tunnel and rolled-in from the west to the east over
299 electrically-powered rollers xed to concrete bases anchored
to the tunnel oor, spaced at 12 m intervals. The pipe column
measured 3,760 m in length, and totalled 304 pipes. The rollers
used are made of nylon, which is resistant to oxidation, corrosion,
and degradation, and which therefore ensures a long operational
life and minimized damage to the external pipe coating as thepipe was pulled across.
A study of thermal expansion found that, as the pipe in
the tunnel was elevated from the ground, there would be no
deformation due to temperature variation. Other features of
the tunnel construction are an anti-explosive internal lighting
system, water drainage by means of longitudinal side channels
along the entire length of the tunnel, and installation of drains
positioned at sites of water ingress through cracks in the tunnel
wall. Shutdown vales are installed on the pipeline at each end
of the tunnel, and the tunnel entries are fenced o to prevent
unauthorised access.
EnvironmentSince the pipeline passes through an area of great environmental
sensitivity, it is also important to note that the choice of the
Figure 10: View o eastern entrance to the tunnel, in the Santana
Mountain range.
Figure 11: The two ronts o the tunnel excavation meet.
Figure 12: The pipeline supported on the rollers inside the tunnel.
Figure 13: ROW restoration.
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tunnel prevented the environmental disturbance of a strip
of approximate length of 4.2 km and 30 m width, and area of
around 126,000 square meters. Located at the Environmental
Protection Area of the So Joo River/Mico Leo Dourado Basin,
this measure contributed to the preservation of the rainforest and
endangered species, including the Tamarin golden lion.
Another mitigation measure accomplished by the construction
of the tunnel was the use of the excavated material for remedial
earthworks in the region. Two sites were used for waste disposal,
one for each end of the tunnel, and the excavated material
was transported using trucks. In one of these locations the
environmental recovery of a landslip was completed with the
material from the excavation of the western front, and initiative
that was commended by regional environmental agencies.
ConclusionOvercoming all the diculties of Cabinas-Reduc-3 (Gasduc-3)
construction resulted in the objectives of Petrobras gas
production expansion plan being achieved. The start of operationof Gasduc-3 conrmed the importance of this enterprise by
Petrobras in expanding the natural gas supply for Brazil. The
project is strategically located at the heart of the Brazilian natural
gas industry, connecting Cabinas in Maca, the countrys main
gas processing plant, with the Campos Elseos compressor station
at Duque de Caxias, nearby Rio de Janeiro.
With this pipeline the transport capacity between these two
points has been increased from 17.9 to 40 MMcm/d, allowing
more natural gas to reach industrial, residential, and commercial
customers, as well as the needs for increased power generation.
AcknowledgmentThe authors Andrade Gutierrez SA, Schaft Engineering, Galvo
Engineering, Contreras, Odebrecht, Techint Engineering and
Constructing SA, and Liderroll, all of whom participated in the
project described in this paper.
This article is based on one presented at the International
Pipeline Conference held in Calgary in September 2010,
and organised by ASME.
Figure 14: Typical city gate otake.
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IntroductionA.Hak Industrial Services Piglet tool is based on one centrally-
mounted ultrasonic transducer which uses a rotating mirror
to reect the ultrasonic beam to the surface of the pipe. The
mirror can be used to focus the ultrasonic beam, creating a small
footprint on the pipe surface or inside the pipe wall, and thereby
allowing very small defects to be detected and sized. The rotating-
mirror principle allows for extreme high resolution as the numberof measurements per circumferential scan can be set without
restriction, and the tools speed can be reduced to enhance the
axial resolution.
The mirror surface was calculated and simulated to have an
optimised beam (a small footprint) in the centre of the pipe
wall to allow detection and sizing of external pinholes. After
optimising the tools ultrasonic beam and resolution, pull
tests were performed on a 10 inch diameter duplex test pipe
with articial defects. These test results were used to conrm
the simulated results and create performance specications
such as detection and sizing capabilities. As the pipeline to be
inspected was 12 inch diameter, a special optimised mirror was
also calculated for this size creating the optimum beam mid-wall of the 12 inch pipeline. The test and simulation results were
combined determine the specications.
The pull test used 10 inch diameter duplex steel pipe having
unknown internal and external articial defects. The pipe was
wrapped and the test witnessed by NAMs representatives in
order to ensure that the data analysts did not have any knowledge
of the location, shape, or size of the defects. This blind test
conrmed the specications and, based on the positive results,
the actual inspection was performed.
The pipeline to be inspected was a 12 km long, 12 inch diameter
duplex steel pipeline with wall thicknesses of 7.6 mm and
9.7 mm. The tool was propelled in a batch of water in an otherwisenitrogen-lled pipeline. As only parts of the pipeline were
suspected to be suering from this type of corrosion, these areas
were inspected at a low inspection speed, with consequent very
high resolution. On other sections, the tool speed was increased
giving a somewhat lower axial resolution. All the results were
monitored online using the tools bre-optic link, and were also
stored on board using the tools on-board memory. When all areas
of interest were inspected the tool was reversed and retrieved into
the launcher by the pressurised nitrogen.
This article describes the optimisation process for the tool, the
tests executed to establish specications and verication, as well
as the in-line inspection itself.
Optimising the Piglet toolA.Hak inspected a 12 inch duplex-steel pipeline using very
high-resolution ultrasound ILI. The companys Piglet tool was
optimised to detect and size-small external pinhole corrosion in
the pipeline.
Pipeline operator NAM decided to use ILI capable of detecting
and sizing this pinhole-type defect in its duplex steel pipeline.
However, after evaluating current magnetic ux leakage (MFL)
and ultrasonic inspection technologies, it became clear that no
tool on the market could meet the desired specications. It was
therefore decided to contract A.Hak to: Optimise its ultrasonic Piglet tool to be able to detect and
size small external pinholes in duplex-steel pipe. NAM would
supply a 10 inch duplex-steel pipe for testing.
To demonstrate the performance of the modied tool on a
blind duplex-steel test pipe. NAM would deliver a test pipe
with articial defects unknown to A.Hak.
Inspect the pipeline if the tool optimisation was regarded
successful.
The Piglets rotating-mirror principle allows for extreme high
resolution as the number of measurements per circumferential
scan can be set without restriction and the tools speed can be
lowered to enhance the axial resolution. The mirror can be usedto focus the ultrasonic beam, creating a small footprint at the
pipe surface or in the pipe wall, and allowing very small defects
to be detected and sized.
NAM (a joint venture between Shell and ExxonMobil) operates several wet gas duplex-steel pipelines in the Netherlands,ranging in diameter from 414 inches. Given the right conditions, duplex-steel pipelines may suffer from (external)pinhole-type corrosion. This type of corrosion is regarded as a risk to the pipelines integrity, and in a constant effort toimprove pipeline integrity, NAM decided to implement in-line inspection (ILI) on these duplex lines to be able to assesstheir condition. Due to the type of material and operating conditions, no standard tool currently available on the marketwas able to detect and size these types of defect. It was decided to support the optimisation of the Piglet ultrasonic in-line inspection tool from A.Hak Industrial Services for this purpose.
Development of an in-line ultrasonicinspection tool for detection ofpinhole-type defects in duplex-steelpipelinesBy Hans Gruitroij, A.Hak Industrial Services, Geldermalsen, Netherlands
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Duplex-steel pipeDuplex stainless steels have a structure that contains both
ferrite and austenite, and derives its name from the two phases
present in the microstructure. This group of steels is intermediate
in terms of structure and alloy content between ferritic and
austenitic stainless steels.
Duplex alloys have higher strength and better corrosion
and stress-corrosion cracking resistance than most austenitic
alloys, and greater toughness than ferritic alloys, especially at
low temperatures; they are therefore often used in dynamically
stressed environments. Duplex alloys have good resistance to
stress-corrosion cracking in a chloride environment.
The corrosion resistance of duplex alloys depends primarilyon their composition, especially the amounts of chromium,
molybdenum, and nitrogen they contain. Duplex alloys are often
divided into three sub-classes: lean duplex, standard duplex, and
super duplex. The duplex used in this application is standard
duplex (1.4462) having high general, localised, and stress-
corrosion resistance properties in addition to high strength and
excellent impact toughness.
Due to these characteristics, duplex steel has found its
applications in the oil, gas, and petrochemical sectors, both
onshore and oshore. Typical applications are platform risers in
the oshore industry and applications where high corrosion rates
can be expected using carbon steel. Nevertheless, given the right
conditions, duplex steel pipes may still be susceptible to metalloss due to corrosion, which can be very small localised pinhole-
type corrosion.
The Piglet ultrasonic ILI toolA.Hak developed and operates a range of ILI tools (referred
to as Piglet) that use high-resolution ultrasound to measure
wall geometry and metal loss in steel pipelines ranging from
442 inches in diameter. The inspection system is designed to
combine the advantages of free-swimming ILI tools with those
of cable-operated tools, with the disadvantages of both having
been eliminated.
The Piglet system consist of an ultrasonic measuring head,an electronics module, a battery pack, odometer wheels, and
a module containing breglass wire; most Piglets are also
equipped with internal data storage. The modular construction
and mechanical design of the tool enables the inspection of non-
piggable pipelines, and the tool can be propelled bi-directionally.
The displacement of the Piglet tool is the same in as free-
swimming inspection pigs in which the tool is propelled by theow of the medium in the pipeline. During the inspection run, the
breglass cable transmits all data from the tools measuring head
to the external data-acquisition system. These data, in the form
of ultrasonic echo patterns for each measurement (typically every
510 mm) are stored, displayed, and analysed to determine any
anomalies in the pipeline.
The data-acquisition system translates this signal into
several outputs that are presented on-line, including full-colour
ultrasonic C-Scan images showing the wall thickness of the
pipeline. The most critical anomalies are identied on-line and
reported, enabling corrective action to be taken immediately if
necessary. Thereafter, the inspection data are post-processed and
a detailed analysis is made of all defects and anomalies for thenal assessment report.
In order accurately to detect and size defects and corrosion of
the pipeline, analysis software is used. Apart from extra (lter)
settings and extended algorithms, the analysis software allows
the operator to use other scans such as the B-scan (Figure 1)
which represents all A-scans of one circumference (one mirror
revolution) in a one-colour plot, resulting in all (raw) signal
information of this circumference.
Performance optimisation for small pinhole-type defects
As the resolution can be easily set, the main focus of this projectwas the ultrasonic beam itself. The mirror prole can be calculated
and a new mirror can be manufactured in order to have an
optimised (i.e. small) footprint in the middle of the pipe wall.
Figure 1: Data presentation:1. Wall thickness (WT C-scan)
2. Distance o centre to inner wall (IR C-scan)
3. Signal amplitude o the inner-wall reection
4. Signal amplitude o the outer-wall reection
5. Visualisation o the ultrasonic signal (A-scan)
6. Visualisation o all A-scans o one circumerence (B-scan)
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To be able to detect and size pinhole-type of defects, a
programme was set up to optimise the tools performance, the
main issues being:
Resolution, high circumferential and axial resolution
Focal point position, inner surface, mid-wall, outer wall
Focusing mirror, calculate new mirror for optimum beam
prole
Transducer, select frequency, diameter and bandwidth
Beam prole simulation, 3.5 MHz versus 5 MHz, 10 inch
versus 12 inch.
ResolutionThe Piglet tool is based on one ultrasonic transducer mounted
centrally in the pig with the ultrasonic beam pointing in the
axial pipe direction onto a mirror. This mirror rotates and
reects the ultrasonic beam onto the pipe wall; the inner and
outer wall echoes reect back onto the mirror and the ultrasonic
transducer. This principle allows for extreme high resolution asthe number of measurements per circumferential scan can be
set without restriction.
The number of measurement per circumference and the
speed of the tool hence determine the circumferential and
axial spacing between measurements. As standard, the
system is set to at least one measurement every 10 mm in both
circumferential and axial directions. Increasing the number of
measurement per circumference increases the probability of
detection (PoD). If the inspection speed is decreased, the same
applies for the axial direction.
Focusing the mirror and beam proleThe mirror can be used to focus the ultrasonic beam.Together with the ultrasonic transducer itself, the shape of
the mirror surface is one of the key parameters that dene the
footprint dimensions of the ultrasonic beam. The mirror can
be exchanged for one with specic measurements, creating a
small footprint at the pipe surface or in the pipe wall to optimize
detection of specic anomalies, allowing very small defects to
be detected and sized. The mirror in this case was designed to
have an optimized (i.e. small) footprint in the middle of the pipe
wall for both 1012 inch pipe internal diameters.
Computer simulation of the ultrasonic beam indicated
elliptical footprints with an average diameter (at -6 dB sound
pressure) of around 4.1 mm for a 3.5 MHz transducer, and ofaround 2.8 mm for a 5 MHz transducer at the mid-wall position
of a 10 inch duplex-steel pipe of 10 mm wall thickness. For the
12 inch pipe, the beam diameters were around 4.9 mm for the
3.5 MHz, and 3.3 mm for the 5 MHz, transducers. The average
footprint (diameter) was thereby approximately 20 per cent
larger than in the 10 inch pipe. Given the higher resolution, and
after testing the 5 Mhz transducer on the duplex steel, it was
decided to use the 5 Mhz conguration for the pull tests, the
blinds test, and eventually for the actual inspection. Based
on the mirror dimensions as used in the simulations, a new
mirror was manufactured for both 10 inch and 12 inch pipes,
and mounted inside the measuring head of the Piglet.
Figure 2: UT sensor.
Figure 3: Mirror calculation.
Figure 4a: Beam profle in liquid.
Figure 4b: Beam profle mid-wall.
Figure 5: Calibration pipe.
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Performance testsThe new conguration was assembled and tested in the 10 inch
duplex-steel calibration pipe provided by NAM, in which known
articial defects had been machined. The articial defects were
external and comprised at-bottom holes (FBH) located at 50 per
cent wall thickness (mid-wall) and spherical-shaped holes located
at 25 per cent, 50 per cent, and 75 per cent of the wall thickness.
Both types of hole ranged from 1 mm to 20 mm in diameter (1, 2, 3,4, 5, 6, 8, 10, 15, and 20 mm).
As the reectivity of the FBH is higher than that of the
spherical-shaped defects, it was expected that these would be
easy to detect; the real challenge was the more-realistic spherical-
shaped defects, from which it could be expected that the mid-wall
defects would be slightly easier to detect.
Tool speedThe detection and sizing performance of the tool was evaluated
by pull tests in the calibration pipe. As the tool speed (axial
resolution) is an important factor in the detection performance,
the tests were performed using dierent speeds (17 m per hour,100 m per hour, and 200 per hour). The velocity of 100m per
hour should give approximately 100 per cent coverage at the
measurement resolution of 2.4 mm (circumferential) and
3.2 mm (axial). Evaluation of the tests indicated that 100m per
hour was an optimal speed: lower speed (higher resolution) does
not signicantly improve the performance, but at higher speeds
(lower resolution) the smaller defects are missed.
Probability of detection (POD)The 100 m per hour test was repeated ten times and, based
on the test results, the POD was estimated at 90 per cent inthe 10 inch pipe with nominal wall thickness of 10 mm for the
following defects:
2mm diameter at-bottom holes;
3mm diameter spherical-shaped defects at 50 per cent
remaining wall thickness; and,
4mm diameter spherical-shaped defects at 25 per cent and
75 per cent remaining wall thickness.
Based on the POD for the optimal (laboratory) testing, a
realistic POD for pitting-type defects in the 10 inch and 12 inch
duplex-steel pipes was estimated. Realistically, the 50 per cent
POD in the 10 inch duplex-steel pipe for a circular defect was
around 3 mm, and in the 12 inch pipe was around 4 mm. For aPOD of 90 per cent, the defect diameter was expected to be
6 mm in the 10 inch pipe, and 7 mm in the 12 inch pipe.
Figure 6: Data-calibration pipe.
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Depth sizingThe remaining wall thickness was determined using the data-
post process software. The results were plotted against the actual
value (certied value) and the comparison is given in Figure 8.
The depth-sizing error (actual minus reported) was, on average,
0.29 mm with a standard deviation of 0.38 mm. This resulted in a
sizing accuracy of 0.6 mm at 80 per cent certainty.
DiscussionSome of the deepest defects were not detected or were not
sized properly. The spherical-shaped defect with a depth of
75 per cent (25 per cent remaining wall thickness) was detected
only due to the loss of any back-wall reection, but a wall
thickness could not be measured at all due to the fact that no
reections from the defect could be distinguished. The reason
for this is that the actual depth was 96 per cent, resulting in a
remaining wall thickness of less than 1 mm, which implies that
the reection from the defect is interfering with the inner-wall
reection and cannot be measured. This defect was not usedduring the statistical analyses.
In addition it was concluded that detection of defects with a
remaining wall thickness
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witnessed by a NAM representative. This second blind test was
successful and data were analysed using a special version ofthe data-analysis software which had been developed to detect
small defects in the ultrasonic signal between inner and outer
wall reections.
During the second test run the results were displayed immediately
on-line, and defect indications immediately were shown on the
wall-thickness and on the outer-wall-amplitude C-scans.
The data were analysed directly after the test using the
standard post-processing software.
From the detected defects the depth, length, and width of
each were determined in the presence of the client. In addition,
the internal/external discrimination was determined. For each
detected defect this was implemented in the C-scans after post-
processing and presented in a Word document.The data were then processed using a special version of
the data-analysis software, in which extra features helped to
detect the small reections which may be present inbetween
the inner and outer-wall reections originating from small
defects. The defects were boxed manually, giving the width and
length sizing. The remaining wall thickness was sized either
automatically or manually.
The list of known defects was provided after reporting and
was used to compare the reported defects with the actual values.
The detection performance, depth, length, and width sizing was
determined for both the internal and external defects. It must
be noted that there were also defects present having a V-shape,which were not present in the calibration pipe.
Three indications are not present in the list of known defects,
and may have been present in the pipe before it was machined.
ResultsThe actual defect depths values from all defects, regardless of the
type, are plotted in Graph 1 against the defect depths as reported
by A. Hak. The defects that were not detected are plotted on the
horizontal axis (on which the reported depth is taken as 0 mm).
The actual defect length and depth values of the internal
defects are plotted in Graph 2. From the six defects with a
diameter of 2 mm, only one was detected and sized. All defects
with a diameter 3mm were detected and sized. These detection
results conrm the realistic POD curve.
The actual defect length and depth values of the external
defects are plotted in Graph 3. From the five conical defects
with a diameter of between 2 and 3mm, no defect was
detected. From the four saw-cut defects along the girth weld,
only one was detected. All defects with a diameter 5.2 mm
were detected and sized. These detection results confirm the
realistic POD curve.
The actual defect depths are plotted against the reported
defect depths in Graph 4 for all internal defects. The averagedepth values of the defect depths that were detected are slightly
oversized with an average dierence of 0.37 mm at a standard
deviation of 0.60 mm. This results in a sizing accuracy for internal
defects of 0.9 mm at 80 per cent certainty.
The actual defect depth is plotted against the reported defect
depth in Graph 5 for all external defects. The average depth values
of the defect depths that were detected are slightly undersized
with an average dierence 0.26 mm at a standard deviation of
0.70 mm. This results in a sizing accuracy for external defects of
0.9 mm at 80 per cent certainty. The saw-cut defects are ignored
for this analysis.
The actual defect lengths are plotted against the reported
defect lengths in Graph 6 for all internal and external defects.
The average length values of the defects that were detected
are slightly undersized with an average dierence 0.7 mm at
a standard deviation of 2.4 mm. This results in a length sizing
accuracy of 3.2 mm at 80 per cent certainty.
The actual defect widths are plotted against the reported
defect widths in Graph 7 for all internal and external defects.
The average length values of the defects that were detected
are slightly undersized with an average dierence 0.6 mm at
a standard deviation of 2.4 mm. This results in a length sizing
accuracy of 3.2 mm at 80 per cent certainty.
Summary of tool specicationsFrom the evaluation of the inspection data of the blind test
pipe it can be concluded that the defect POD (90 per cent POD for
defects >6 mm), length and width-sizing accuracy (4 mm at 80 per
cent certainty) as dened via the calibration pipe are conrmed.
The defect depth-sizing accuracy, however, was found to be less
and dened to be 0.9 mm at 80 per cent certainty.
The tool evaluation was based on tests in the 10 inch pipe,
whereas the actual pipeline has a diameter of 12 inch. Due to
the design of the tool, this larger diameter has some eects on
the detection and sizing capabilities, as the diameter of the spot
of the UT beam is approximately 20 per cent larger. The depth-
sizing accuracy is expected not to be signicantly inuenced, butthe POD and defect length and width sizing are assumed to be
reduced. The POD is already extrapolated from the 10 inch pipe to
the 12 inch pipe.
Figure 11: Test set-up.
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The specications of the tool, applied to in the 12 inch pipe are
estimated to be:
POD: 90 per cent for defects with length and width 7 mm;
50 per cent for defects with length and width 4 mm;
Defect depth-sizing accuracy: 0.9 mm at 80 per cent certainty;
Defect length- and width-sizing accuracy: 4 mm at 80 per
cent certainty; and, Defects with a remaining wall thickness of 2 mm will be
missed.
InspectionBased on the initially reported results of the blind test, it was
decided to inspect the pipeline with the newly designed Piglet
tool. The pipeline had some sections of interest on both sides and
it was decided to perform two separate inspection runs.
Displacement and pre-inspection cleaningAfter the equipment was rigged-up at both pipe end locations
including tanks, separator, and temporary are, the nitrogentank and pump were installed to displace the line by running
two medium-density pigs through the pipeline. The pigs arrived
together with 10 cubic metres of condensate at the receiving end.
The next day two brush pigs and a foam pig were sent within abatch of 30 cubic metres of pre-heated water down the pipeline,
with nitrogen. After the three pigs were retrieved from the
receiver, two brush pigs were run with nitrogen.
Next, a further batch of 30 cubic metres of pre-heated water
was sent together with two brush pigs sealed with a bi-directional
pig. After the three pigs were retrieved, two brush pigs were again
run with nitrogen.
Finally, a further 30 cubic metres batch of pre-heated water was
pumped into the pipeline. A b-directional pig with gauge plate
was sent at the end of the batch. The gauge-pig was retrieved
without any damage, clearing the line for the inspection. The
pipeline was pressurised to 8 bar and isolated before the crew leftthe location.
InspectionAs high-resolution inspection of only short sections of
interest was required, the tool was pumped at a relatively high
speed to the area of interest, after which it was propelled at
a speed of around 90m per hour. The inspection data, tool
speed, and location were monitored on-line, and the speed
was controlled manually.
A bi-di pig was sent with 30 cubic metres of water before the
inspection Piglet was launched. The inspection was set with
a speed of 300 m per hour until the Piglet arrived at the rst
section of interest. This section was inspected with a speed ofapproximately 90 m per hour, where the pig speed was increased
to 750m per hour toward the next section of interest.
This second section of interest was covered with a speed of
approximately 90 m per hour, and the pigs were then returned
using the nitrogen pressure in the line. The inspection Piglet and
the bi-directional pig were retrieved and the pipeline was isolated
again with a remaining pressure of 7 bars. The next day, a run
from the other end was executed.
All results were monitored online using the tools bre-optic link,
as well as being stored onboard using the tools on-board memory.
Data analysis and reportingThe inspection data were been recorded and a eld report was
made directly after the inspection. Afterwards the data were
processed and reported in a nal report.
Figure 12: Receiver set-up.
Figure 13: Launcher set-up.
Figure 14: Dig up.
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The inspection indicated that no corrosion defects were
detected. Based on the estimated, realistic, detection
capabilities of the Piglet in a 12 inch duplex-steel pipeline, it can
be concluded that with a probability of 90 per cent no corrosion
defects with lengths and widths greater than 7 mm (or greater
than 4mm with a POD 50 per cent) are present in the pipeline at
the sections of interest.
In both sections of the pipeline, however, some lamination
features were reported. Laminations are normally not a threat
to the integrity of the pipeline, but as lamination features are
not expected to occur in duplex-steel pipeline material, NAM
was advised to check one or more of these features at an easily
assessable location.
Dig-up vericationTo verify the lamination features, a dig up was performed.
Manual ultrasonic testing (UT) did not nd the mid-wall feature,
but it is clear that no external corrosion was present at this
location. After double-checking the correct location of the dig-upsite, it can be concluded that indeed the features were correctly
reported as mid-wall features.
To further examine the ability of the system to discriminate
between internal, external, and mid-wall features, the pipe used
for the blind test was examined. During the blind test three
features were reported that were not on the defect list, one feature
being reported as mid-wall. This pipe, wrapped on the outside,
was cleaned and examined and it became clear that all three
reported features were present, the mid-wall feature being located
using hand-held UT.
Summary The development of the Piglet tool with optimised ultrasonicspecications to detect and size pinhole defects in a duplex-
steel pipeline was successful.
The tool specications for the 12 inch, 9.5 mm wall thickness,
duplex-steel pipeline at a tool velocity of 90m per hour were:
50 per cent POD for defects with a length and width > 4mm
90 per cent POD for defects with a length and width > 7mm
Length and width sizing accuracy 4 mm at 80 per cent
certainty
Defect depth sizing accuracy 0.9 mm at 80 per cent certainty.
The inspection of the wet gas pipeline in a liquid batch was
successful.
No corrosion defects were detected.
Figure 15: Test pipe.
Graph 1. Actual vs reported deect dimensions, all deects.
Graph 2. Detection o internal deects based on type and
dimensions.
Graph 3. Detection o external deects based on type and
dimensions.
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Graph 4. Actual vs reported deect dimensions, internal deects
by type.
Graph 5. Actual vs reported deect depth dimensions, external
deects by type.
Graph 6. Actual vs reported deect length dimensions, all deects. Graph 7. Actual vs reported deect width dimensions, all deects.
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news wraP
April 2011 ews WrapHeading into April, the pipeline industry has continued to move projects forward in key energy hubs around the globe.In Canada, the Mackenzie Valley Pipeline received the backing of the NEB, while TransCanadas Keystone XL Pipelinehas moved into the final stage of review. The final route was selected for the Greek section of the Trans-AdriaticPipeline while Brazils Petrobras announced it will construct an export pipeline to connect an offshore LNG plant toshore. In the Middle East, bids are now being accepted for the engineering, procurement and construction contract foran onshore gas pipeline in Iraq and in north Africa the Medgaz Pipeline has been commissioned, transporting Algeriangas to the Spanish coast.
North AmericaMagellan Midstream Partners and M3 Midstream are developing
a 290 km pipeline to transport crude oil and condensate from theEagle Ford Shale formation to Magellans existing distribution
terminal in Corpus Christi.
The pipeline will have the capacity to supply more than
180,000 bbl/d of oil and condensate to Gulf Coast markets in Corpus
Christi, Houston and Beaumont, Texas, and St James, Louisiana.
Design of the pipeline is nearing completion and pipeline
construction and terminal modications are planned to take 14 to
18 months to complete.
Canadas National Energy Board (NEB) has issued a Certicate
of Public Convenience and Necessity for the 1,196 kmMackenzie
Valley Pipeline, part of the Mackenzie Gas Project.
The Mackenzie Valley Pipeline is being planned to run from theBeaufort Sea to northwestern Alberta, and is designed to carry up
to 1.2 Bcf/d of gas.
The project requires a number of permits and authorisations
from other boards and government agencies before construction
can commence.
TransCanadas Keystone XL Pipeline has now entered the nal
stages of review by the United States Department of State.
TransCanada President Russ Girling said We expect a nal
regulatory decision for this project by late 2011 and we are pleased
the Department of State has committed it will conclude its review
ofKeystone XL by the end of the year. The Keystone expansion is
expected to be operational in 2013.
In oshore news, Foster Wheelers Global Engineering andConstruction Group has been awarded a detail design contract by
Enbridge Oshore for the deepwater Big Foot Oil Pipeline and
Walker Ridge Gathering System (WRGS) export gas pipelines
located in the Walker Ridge area of the Gulf of Mexico.
The 72.5 km, 20 inch diameter Big Foot Oil Pipeline will connect
the Big Foot eld to a subsea connection on existing deepwater
pipeline infrastructure and have the capacity to transport
100,000 bbl/d of crude. The Big Foot eld lies in the Walker
Ridge Area of the Gulf of Mexico and is estimated to contain total
recoverable resources in excess of 200 MMboe.
The WGRS involves the construction of 306 km of 812 inch
diameter pipelines to provide natural gas gathering services tothe Jack, St Malo and Big Foot ultra-deepwater developments.
Both projects are targeted to be operational for the end of 2012.
AsiaChina National Petroleum Company has commenced the
Zhou Ping River crossing as part of the Second West East
gas pipeline.
The company has constructed a single coerdam in the Zhou
Ping River and pre-welded pipe is currently been lifted into place.
The whole crossing project is expected to be completed by
10 April 2011.
In Myanmar, horizontal-directional drilling of the Irrawaddy
River crossing for the Myanmar China Gas Pipeline and the
Myanmar China Oil Pipeline has commenced.
The groundbreaking ceremony for the crossing was attended by
Myanmar Minister of Energy Lun Thi.The 1,790 m pipeline crossing is being drilled through layers of
rock and sand by CNPC subsidiary Pipeline Bureau.
The Myanmar China Pipeline project involves the construction
of oil and gas pipelines running between the two countries. The
pipelines originate at Kyaukryu port on the west coast of Myanmar
and enter China at Yunnan's border city of Ruili.
EuropeTAP AG has nalised the route renement study of the onshore
Greek section of the Trans-Adriatic Pipeline.
More than 50 national and international experts conductedcomprehensive and detailed studies of a 50 km wide corridor
between Thessaloniki and the Greek-Albanian border. Three
Coerdam excavation o the main channel on CNPCs Second West
East Pipeline.
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extensive eld missions were organised in northern Greece
to identify geological, environmental and cultural heritage
constraints, as well as safety and social concerns.The survey work was led by E.ON, one of the shareholders in
the project.
Stroygazmontazh has commenced construction of the sixth
string of the Ukhta Torzhok Pipeline in Russia on behalf of
Yamalgazinvest.
Currently preparatory works are underway, and mobilisation of
machinery is being carried out.
Stroygazmontazh will construct 486 km of the gas pipeline, the
total length of which is 972 km. The 56 inch diameter pipeline will
have an operating pressure of 9.8 MPa, with a designed output of
81.5 Bcm/a of gas.
The construction team will have to perform major HDDcrossings of the Malaya Severnaya Dvina, the Libenga and the
Sukhona rivers. The length of the crossing under the Libenga
River is more than 1,100 m.
Construction on the Ukhta Torzhok Pipeline commenced in
December 2010 and is scheduled to be completed in December 2012.
Technip has been awarded an installation contract, worthmore than $US27.9 million, by EOG Resources UK Ltd, for the
development of the Conwy Field, located in the East Irish Sea.
The Conwy Field Development contract covers welding and
installation of an 11.4 km, 8 inch diameter production pipeline
and an 8 inch diameter water injection pipeline which is to be
trenched and backlled.
TechnipsApache IIand Orelia will complete the pipelay
activities by the third quarter of 2012.
Middle EastSouth Oil Company of Iraq (SOC) has invited bids for an
engineering, procurement and construction contract for its
105 km, 18 inch diameter gas pipeline, which will export gas from
the Zubair eld in southern Iraq.
Map o the Bahia regasifcation terminal and export pipeline, Brazil.
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The onshore pipeline will transport 100 MMcf/d of gas from the
Zubair depot to the Fao depot, at the north of the Persian Gulf.
Saudi Aramco has awarded Saipem the engineering,
procurement, installation, and commissioning (EPIC) contract
for the Al Wasit Gas Programme and associated pipelines in the
Persian Gulf.
The contract includes the construction of a 36 inch diameter,
260 km export trunkline and approximately 200 km of mono-
ethylene glycol (MEG) pipelines, 200 km of subsea electric and
control cables and 40 km of oshore owlines.
The scope of work also includes the shore approaches, about
120 km of onshore pipelines, and encompasses the engineering,
procurement, fabrication, and installation of 12 wellhead
platforms, two tie-in platforms and one injection platform.
The oshore activities will be performed mainly by theCastoro
IIand Castoro Otto vessels.
AfricaThe valve connecting the 210 km Medgaz Pipeline from BeniSaf, Algeria, to the Spanish gas system has been opened at a
ceremony in Almeria, Spain. The opening of the valve is part of
the final phase of the test sequence for the pipeline.
The sequence for commissioning the Medgaz Pipeline consisted
of a phase of commissioning and a start-up phase. During the
commissioning phase all of the pipeline systems were veried,
while gas has been gradually introduced into the pipeline during
the start-up phase.
Further south, Acergy has awarded Serimax the welding contract
for a major pipeline replacement project, oshore Nigeria.
Acergy is removing existing risers and installing approximately15 km of corrosion-resistant alloy (CRA) pipelines and associated
risers for ExxonMobil on the Oso Re project.
The purpose of the Oso Re project is to restore mechanical
integrity of the condensate pipeline systems between oshore
platforms at the Oso eld, oshore in the Bight of Biafra, and to
repair the Oso Re topside facilities damaged by re in 2005.
Serimax has been awarded the automatic welding scope for the
CRA pipelines with diameters of 16 inch, 12.75 inch and 10.75 inch.
South AmericaBolivias YPFB Transporte will build a new network of pipelines
in the south of the country to transport natural gas liquids.
The Southern Expansion Liquid System project will
connect YPFBs refineries to the domestic markets and will
transport NGLs to the departments of Tarija, Chuquisaca,
Santa Cruz, and Cochabamba.
The engineering will be completed by mid-April 2011 after
which the length of the pipeline network will be nalised.
Currently approximately 200 km of 1012 inch diameter pipeline
has been proposed.
YPFB is considering two options for the increased LPG
production: exporting to Argentina or constructing a propane
pipeline to Sica Sica in Bolivia and on to Ilo in Peru, and Arica innorthern Chile.
Brazils Petrobras will install a third oshore LNG terminal and
construct a pipeline to export gas from the terminal to Brazils
onshore pipeline network in the state of Bahia, Brazil.
The Bahia regasication terminal will be installed in the Bay
of All Saints and will have the capacity to regasify 14 MMcm/d. A
49 km, 28 inch diameter pipeline will be constructed to connect
the terminal to the pipeline network, including an oshore
section of 15 km.
The new export pipeline will interconnect with the pipeline
network at two sites: one in the Bahia network, at Candeias, and
the other at kilometre point 1,465 on the Cacimbas Catu Pipeline,
a section of the Gasene Pipeline commissioned in March 2010.
The LNG terminal will supply natural gas to the state of Bahia, the
largest consumer of gas among the northeastern Brazilian states.
Work on the project will begin in March 2012 with completion
scheduled for August 2013.