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1 PiPelines international digest | aPril 2011

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.

[email protected]

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

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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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teChniCal

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



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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teChniCal

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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teChniCal

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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teChniCal

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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teChniCal

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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teChniCal

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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teChniCal

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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teChniCal

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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news wraP

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.