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HomeMy WebLinkAboutC_Public_Comment_39.b_1800502.email_attch2of2edition no5 | MAy 2015 Journale ISSN 2196-4300 www.pipeline-journal.net In the past, data availability and reliability characterized the man challenges to understanding and improving operations in the oil & gas industry. Today, data flows in by the miliseconds, however-most of the engineering practices remain the same. Are oil companies extracting the full potential of their investment in data infrastructure? Fathom Solutions offer a Deeper Understanding to the vast databases of information available in the Oilfield today. C M Y CM MY CY CMY K Print Ad-final.pdf 1 5/12/15 3:18 PMMay 2015ReSeaRch industry & Practice development & technology NewS eveNtS Conferences & Seminars Pipeline Technology Conference10th A N N IV E R S ARY 10th anniversary of 8-10 June 2015, Berlin, Germany evenT ediTion Media Partners International Pipeline Technology Journal 10th PiPeline technology conference europe’s Leading Conference and exhibition on new Pipeline technologies 8-10 June 2015, estrel Berlin, Berlin, Germany www.pipeline-conference.com 10th A N N IV E R S A RY eXHiBitOrs sPOnsOrs suPPOrters EDITORIAL Welcome Message from the editor The Pipeline Technology Journal (ptj) is published for the fifth time. Its design as well as its internal structure clearly sharpened in comparison with the first issues. what remain are the close ties to the Pipeline technology conference (ptc) in Berlin and the occupation with research and development at an early stadium. It thus offers the possibility to support discussions among the pipeline community on new developments considering experiences worldwide. Unlike the Poster-show that establishes a selective professional public during the annual ptc conference, the journal ptj will be thus published four times a year to intensively report about research and development helping to optimize the construction, operation and life support of pipelines. the triggers for this promotion were the requirements of many opera- tors who are participants of the Pipeline technology conference (ptc) to speed in dealing with issues of pipeline safety and longevity. help us to meet these demands and provide us Your new solutions. Our ptc editorial and ptc advisory Board are available to further encourage the development of Pipeline technolo- gies from the point of view of safety and durability. Yours sincerely > Dr. Klaus RItter, Editor in Chief Dr. Klaus Ritter ptc aDvISORY cOMMIttee / ptj eDItORIal BOaRD cHAIRMeN MeMbeRs dr. Klaus ritter, President, eiteP institute uwe ringel, Managing director, Ontras Gastransport Muhammad sultan al-Qahtani, General Manager, Pipelines, saudi aramco Waleed al-shuaib, Manager support services Group (s&eK), Kuwait Oil Company (KOC) Juan arzuaga, executive secretary, iPLOCa arthur Braga, director, rB&B Consulting uwe Breig, Member of the execu- tive Board / Bu utility tunnelling , Herrenknecht Filippo Cinelli, senior Marketing Manager, Ge Oil & Gas Mohamed daoud, Manager (Projects QM), abu dhabi Company for On- shore Oil Operations (adCO) ricardo dias de souza, Oil engi- neer - senior advisor, Petrobras / transpetro Jens Focke, Head of sales & Mar- keting, GeOMaGiC andreas Haskamp, Pipeline Joint Venture Management, BP europa se dr. Hans-Georg Hillenbrand, director technical services, europipe Jörg Himmerich, Managing director / technical expert, dr.-ing. Veenker ing.-ges. Maximilian Hofmann, Managing director, MaX streiCHer dr. thomas Hüwener, Managing director technical services, Open Grid europe Mark david iden, director, Charterford House dirk Jedziny, Vice President - Head of Cluster ruhr north, evonik industries Cliff Johnson, President, PrCi - Pipeline research Council international dr. Gerhard Knauf, Head of div. Mech. eng., salzgitter Mannesmann Forschung / secretary General, ePrG Wolfgang Krieg, President, ndt Global reinhold Krumnack, div. Head, dVGW - German technical and scientific association for Gas & Water Mike Liepe, Head Business solution Line O&G Pipelines, siemens ralf Middelhauve, Head of Central dept. Process industrie / Plant engineering and Operation, tÜV nOrd systems Prof. dr. Joachim Müller-Kirchen- bauer, Head of dept. Gas supply, tu Clausthal Frank rathlev, Manager of network Operations, thyssengas Markus rieder, Head of department Pipelines, tÜV sÜd industrie service Hermann rosen, President, rOsen Group ulrich schneider, Business development Manager Continental europe, Ktn Carlo Maria spinelli, technology Planner, eni gas & power asle Venas, Global director Pipelines, dnV GL tobias Walk, director of Projects – Pipeline systems, iLF Consulting engineers Heinz Watzka, senior advisor, eiteP institute Conference Management dennis Fandrich, director Confer- ences, eiteP institute PiPeLine TeCHnoLoGy JoURnAL 3 noRd STReAM UndeRWATeR Tie-in BACkGRoUnd each of the two Nord Stream Pipelines is built in three sections. Once completed, the sections must be welded together to form the 1,224 kilometre pipelines. this "tie-in" process takes place on the seabed in an underwater welding habitat. welding oper- ations are remotely controlled from a support vessel, and divers assist and monitor the subsea construction work. Andrey voronov (Offshore Manager, Nord Stream aG) will report about the Nord Stream Offshore Pipeline Repair Strategy during the 10th Pipeline technology conference, 8-10 June 2015 Berlin, Germany www.pipeline-conference.com © by Nord Stream CONTENT HiGHLiGHTS MaY 2015 eDItION 05 46 CSSP - Common Seawater Supply Project as the second largest oil producer of OPec nations, Iraq’s economy fully depends on the stability and growth of the national oil industry. It is therefore of paramount importance to keep the oil production at target level. to achieve this goal it is necessary to apply secondary oil recovery methods. dent Hunting For pipeline integrity management detailed feature assessments based on finite element analysis (FEA) are getting more and more important. considering dents as one of the major integrity threads of pipelines, the finite element analysis helps to differentiate between severe and benign dents. Remote Welding Systems (RWS) Statoil have, after several years of testing and technical qualification work, developed a Remote Welding System that was qualified for con- tingency in the Pipeline Repair System pool services in December 2014. the system is rated for operation down to 1000msw and covers pipe- lines which are in depths exceeding the limit for diver assisted opera- tions, which is currently 180msw. new era of in-Line inspection (iLi) Intelligent Pigs for Internal Inspection & Repair welding of cross-country Pipelines capital cost for crude trunk pipelines is very high, depending on the pipeline steel grade, the design wall-thickness, and the length of the pipeline. these factors often force the product owners to construct most of the cross-country pipeline network in a single channel, making it difficult to shutdown for inspection, maintenance, or repair. 40 Grand Theft Pipeline Finite element simulation of guided waves to detect product theft from pipelines 22 Pipeline voltage Possible Reasons why calculations of induc- tive interference pipeline voltages are highter than conducted measurements 32 Buried Steel Seismic analysis of buried steel pipeline subjected to ground deformation with emphasis on the numerical modelling optimization 46 50 56 60 6 PiPeLine TeCHnoLoGy JoURnAL CONTENT THiS iSSUe’S CoMPLeTe ConTenT world News In-line Inspection of challenging Pipelines validated with Flow loop Simulations Sawyer Mfg. co. improves the Ratchet clamp-Model 255 atmos International’s new theft solutions at Ptc Tracto Technik offers solutions for HDD Projects during Pipeline technology conference (ptc) New Research into aerial vehicle technologies to enhance Pipeline Monitoring Discovery™ completes successful deployment on Shell assets in the gulf of mexico technip’s subsidiary tipiel awarded a contract for a new gas pipeline in Peru Shawcor announces contract to Provide Pipe coating Services for the GNea Project in argentina Xcel energy will use drone technology to protect and improve energy reliability and safety Special Feature PiPeLine TeCHnoLoGy ConFeRenCe (ptc) 7 PiPeLine TeCHnoLoGy JoURnAL 10th Pipeline technology conference (ptc) anniversery 8-10 June 2015 in Berlin 16 Pipeline voltage - possible reasons why calculations of inductive interference pipeline voltages are highter than conducted measurements Buried Steel - Seismic analysis of buried steel pipelines subjected to ground deformation with emphasis on the numerical modelling optimization Grand Theft Pipeline - finite element simulation of guided waves to detect product theft from pipelines common Seawater Supply Project (cSSP) - enabling one of the world’s top oil producing regions Dent Hunting - using high resolution in-line inspection technologies and finite element analysis Remote welding System (RwS) - new fully remote hyperbarbic welding system rated to 1000 msw New era of In-line Inspection (IlI) - intelligent Pigs for internal inspection & repair welding of cross-country Pipelines ReSeARCH / deveLoPMenT / TeCHnoLoGy 7 PiPeLine TeCHnoLoGy JoURnAL In-Line Inspection of Onshore and Offshore Pipelines Geohazards and Geotechnics in Pipeline engineering Microbiologically influenced corrosion (MIC) and its impact on pipeline corrosion management 8 10 10 11 12 14 14 15 15 15 22 32 40 46 50 56 60 70 70 70 PiPeLine TeCHnoLoGy JoURnAL 7 indUSTRy And PRACTiCe 7 PiPeLine TeCHnoLoGy JoURnAL ConFeRenCeS / SeMinARS / eXHiBiTionS 7 PiPeLine TeCHnoLoGy JoURnAL noRTH AMeRiCA enbridge Pipelines, transcanada corporation and Kinder Morgan canada have signed a Joint Industry Partnership agreement to conduct research into aerial-based leak detec- tion technologies with the aim of enhancing pipeline safety throughout North america. Page 14 SeATTLe / U.S.A Quest Integritiy Group announces flow loop simulation capabilities, including client-specific pipeline configurations, to validate its Invista™ ultrasonic in-line inspec- tion (IlI) technology in demanding environments. visit Quest Integrity Group at ptc 2015 stand 41. Page 10 GULF oF MeXiCo Discovery™, the world’s first subsea CT scanner for flowlines, has successfully completed the first deep-water deployment on Shell-operated flowlines in the Gulf of Mexico. Page 14 MinneAPoLiS / U.S.A Xcel energy will use drone tech- nology to protect and improve energy reliability and safety Page 15 okLAHoMA / U.S.A Sawyer Manufacturing company has redesigned its Ratchet clamp with a lower profile to allow better access to the butt join, helping welders effectively and quickly align and weld pipe. Page 10 ARGenTiniA Shawcor ltd. announced that its pipe coating division has received two contracts for approximately US$55 million from tenaris to provide three layer polyethylene anti-corrosion pipeline coatings for the first and second phase of the argentina Northeast Gas Pipeline (GNea) project. Page 15 indUSTRy And PRACTiCe 8 PiPeLine TeCHnoLoGy JoURnAL WoRLd neWS PARiS / FRAnCe technip’s subsidiary tipiel awarded a contract for a new gas pipeline in Peru Page 15 MAnCHeSTeR / GReAT BRiTAin atmos International (atmos) will celebrate 20 years in the pipeline industry by exhibiting new theft detection solutions at Pipeline technology conference 2015 (stand 52). Page 11 LenneSTAdT / GeRMAny when problems arise on an hDD project, quick action is required to avoid a costly situation. Over the last years, several pipe ramming tech- niques have been developed to assist direction- al drill rigs in difficult situations. Tracto Technik offers such solutions for HDD projects during Pipeline technology conference (ptc) 2015 Page 12 INDUSTRY AND PRACTICE PiPeLine TeCHnoLoGy JoURnAL 9 in-Line inSPeCTion oF CHALLenGinG PiPeLineS vALidATed WiTH FLoW LooP SiMULATionS Quest Integrity Group announces flow loop simulation capabilities, including client-specific pipeline configurations, to validate its InVis- ta™ ultrasonic in-line inspection (IlI) technology in demanding envi- ronments. visit Quest Integrity Group at ptc 2015 stand 41. Quest Integrity conducts flow test loop demonstrations in various locations worldwide and can custom build flow loops for clients to include their real-world IlI challenges such as heavy wall piping, du- al-diameters, reduced port valves, 1D bends, risers, unbarred tees and wyes. By simulating multiple IlI obstacles in a test environment, the company effectively demonstrates the navigational proficiency of the InVista tool, and pipeline operators gain first-hand knowledge of the tool’s capabilities for their pipelines. The company recently constructed a 6-inch custom flow loop for a large, international oil and gas client in houston, texas. the client needs integrity management data for a high-profile, heavy wall sour gas pipeline asset in the United States, but wanted to avoid failed run or stuck tool situations. Quest Integrity’s flow loop simulations included running the tool at varying speeds and bi-directionally to validate data collection and operational capabilities. Invista success- fully overcame the operational trials presented and collected accu- rate data for both known and unknown defects in the line. “As an added value to our clients, we build flow test loops to their specifications to simulate an in-service challenging ILI run in a test environment,” said Stefan Papenfuss, vice President - Pipeline Re- sources, at Quest Integrity. “this provides our clients with procedural information and project confidence while demonstrating the many benefits of the InVista technology for their critical pipeline assets – without the potential risks associated with testing an in-service pipe- line.” For further information: http://www.questintegrity.com/services/inspection-services/pipe- line-in-line-inspection SAWyeR MFG. Co. iMPRoveS THe RATCHeT CLAMP-ModeL 255 Sawyer Manufacturing company has redesigned its Ratchet clamp with a lower profile to allow better access to the butt join, helping welders effectively and quickly align and weld pipe. the ratchet mechanism was also improved with a built-in handle and enclosed threads to protect against dirt and weld splatter, all while re- taining the true double ratchet feature that allows for quicker closure on the pipe to increase speed and performance. this mechanism permits the clamp to align pipe quicker than any other ratchet clamp on the market. the Ratchet clamp is built with a focus on speed and accuracy. this 10-ton ratch- et will deliver precision and rugged durability with ease. the clamp is designed with an open bridgework to allow full 360-degree welding, en- suring a quality weld, and the machined headrings are pre- cision bored for consistent and accurate fit up. Also, the Ratchet clamp’s new yellow color provides high visibility and improved safety. Improvements in the man- ufacturing process have al- lowed Sawyer Mfg. co. to of- fer a price that is even more competitive. “there are a lot of clamps out there,” said Dave hembree, Sawyer Manufacturing vice President. “I believe our cus- tomers will be pleasantly surprised by the small but important chang- es we made with this clamp.” Sawyer equipment is used worldwide in the construction and mainte- nance of pipeline, waste water and sewer lines, marine and offshore applications, gathering and distribution systems, and other welding and pipeline applications. For further information: e-mail sales@sawyermfg.com Send latest Pipeline related news to: ptj@eitep.de www.pipeline-journal.net indUSTRy And PRACTiCe 10 PiPeLine TeCHnoLoGy JoURnAL ATMoS inTeRnATionAL’S neW THeFT SoLUTionS AT PTC atmos International (atmos) will celebrate 20 years in the pipeline industry by exhibiting new theft detection solutions at Pipeline tech- nology conference (stand 52). Atmos already offers Atmos Wave, which detects theft valve move- ment; and atmos wave Flow which, with sensitivity to 0.1% of the flow rate, can potentially detect theft within two minutes. Howev- er, Jun Zhang, Managing Director, atmos, explained, ‘we’re seeing meticulously planned, near-invisible taps by well-organized gangs that significantly impact a pipeline user’s profits. Rapid detection is essential for minimizing financial, environmental, and reputational damage.’ ‘Our powerful new detection solutions enable clients to react instant- ly and catch criminals red-handed.’ ATMoS THeFT neT as illicit connections have become smaller, more intermittent and harder to detect, so detection systems must become more sensitive. this increases the rate of false alarms, which can be costly but also dangerous if they result in genuine alarms being ignored. atmos ex- perts are trained in the latest techniques for spotting theft in action – and offer this unique analysis service to save clients time and loss, and help them prosecute. to collect data, atmos has developed: ATMoS PoRTABLe dATA LoGGeR FoR LeAk And THeFT deTeCTion this case-based autonomous data logging solution can be rapidly deployed – either by your staff or Atmos - to collect the pressure and flow data where taps are suspected. Data can be collected on site or remotely. ATMoS HydRoSTATiC TeSTeR this portable kit takes hydrostatic testing to unprecedented levels. It uses both pressure and acoustic sensors to identify even tiny leaks or intermittent tapping, with location accuracy to 2 meters. It is ide- al for where pipeline integrity testing is mandatory, and negates the need for costly yet limited options with dyed or odorized water. odin this revolutionary battery-based theft detection solution has been designed for pipelines previously in a detection ‘black hole’ – for ex- ample, in areas without power or communications, or where standard detection units are undesirable for aesthetic reasons (as in National Parks.) Small and unobtrusive, it can be hidden near suspected tap- ping points, yet has the sensitivity of permanent detection systems. For further information: Georgina amica-carpenter, Marketing associate tel: +44 161 445 8080 e-mail: georgina@atmosi.com atmos Portable Data logger for leak and theft Detection Battery-based theft detection solution ODIN has been designed for pipelines previously in a detection ‘black hole’. INDUSTRY AND PRACTICE PiPeLine TeCHnoLoGy JoURnAL 11 TRACTo TeCHnik oFFeRS SoLUTionS FoR Hdd PRoJeCTS dURinG PiPeLine TeCHnoLoGy ConFeRenCe (STAnd 47) when problems arise on an hDD project, quick action is required to avoid a costly situation. Over the last years, several pipe ramming techniques have been developed to assist directional drill rigs in difficult situations. Having a ramming hammer on site during HDD projects ensures a trouble free installation as the combination of the hDD technique’s static pulling force with the ramming technique’s dynamic impact offers proven solutions for tough drilling problems. CondUCToR BARReL: inSTALLATion oF CASinG PiPeS FoR Hdd CRoSSinGS the concept behind the conductor Barrel is creating a clear pathway through poor soil conditions so that drilling can begin in more favour- able soil conditions. the success of a drilling operation can often be determined right from the outset. loose, unsupported soils are prime candidates for this method. During the conductor Barrel pro- cess, casings are rammed into the ground, at a predetermined angle, until desirable soil conditions are encountered. the spoil is removed from the casing prior to the drilling operation. Drilling starts within the casing in the favourable soil conditions. the conductor barrel can also serve as a friction-free section during the pullback operation or prevent situations in unstable soils acting in a similar fashion to con- tainment cells. PULLBACk ASSiST the pullback assist technique incorporates the use of both a pipe rammer and an hDD rig working in tandem to get a problematic product pipe installed. When drilling underwater or in loose flowing soil conditions, hydrolock can occur. this happens when the external pressure being put on the product pipe from ground water pressure, drilling fluid pressure and/or soil conditions exceeds the drill rig’s pullback capacity, or the product pipe’s tensile strength. the percus- sive action of a pipe rammer in this situation is used to help free the jammed pipe. dRiLL Rod ReCoveRy: LooSeninG oF JAMMed Hdd dRiLL Rod the principal is the same during drill rod recovery, as it is during bore salvage, however, there are two possible tooling configurations. De- pending on the situation, contractors can remove the drill rod from the ground or, if the rod is still attached to the drill rig, push on the rod while the drill rig pulls back. BoRe SALvAGe: ReSCUinG / ReMovinG JAMMed PRodUCT PiPeS This simple yet highly effective technique is used to remove jammed product pipes. During the bore salvage operation the Grundoram pipe rammer is attached to the end of the partially installed product pipe. the pipe rammer is attached to the product pipe so that it pulls the pipe from the ground. this can be accomplished through a fabricated sleeve. a winch or some form of pulling device is used to assist the rammer during operation. In many cases, the percussive power of the pipe rammer is enough to free the jammed product pipe and allow it to be removed from the ground. For further information: tRactO-techNIK Gmbh & co. KG tel. (+49) 2723 808-0 Fax (+49) 2723 / 808-180 e-Mail: info@tracto-technik.de Internet: www.tracto-technik.de indUSTRy And PRACTiCe 12 PiPeLine TeCHnoLoGy JoURnAL Journale Methane Typical inspection speeds of 50 miles per hour  Real time detection and alarm feature  5 ppm x m sensitivity in 30 mph winds  Maximum altitude up to 300 feet  GPS tracking of fl ight route and methane indications  Digital video recording of entire inspection There are many advantages to using ALMA Gas Leak Inspection Service by ALMA NEW LNG-Monitoring Compressor Stations Storage Areas NEWNEW Gas Monitoring System by LMS-Remote USA & Canada Tel. 425-503-8127 / www.pergamusa.com World Wide Tel. +41 43 268 43 35 / www.pergam-suisse.ch Laser L a s e r PTJ_Heft.indd 1 9/11/2014 12:49:53 PM Pipeline Technology Journal www.pipeline-journal.net ptj@eitep.de www.pipeline-conference.com Publisher Euro Institute for Information and Technology Transfer GmbH Am Listholze 82 30177 Hannover, Germany Tel: +49 (0)511 90992-10 Fax: +49 (0)511 90992-69 URL: www.eitep.de President: Dr. Klaus Ritter Register Court: Amtsgericht Hannover Company Registration Number: HRB 56648 Value Added Tax Identification Number: DE 182833034 Editors in Chief Dr. Klaus Ritter E-Mail: ritter@eitep.de Tel: +49 (0)511 90992-10 Editorial Board Advisory Committee of the Pipeline Technology Conference (ptc) Editorial Management & Advertising Rana Alnasir-Boulos E-Mail: alnasir-boulos@eitep.de Tel: +49 (0)511 90992-20 Designer / Layouter Admir Celovic Terms of publication Four times a year, next issue: September 2015 Paper deadline: August 15th 2015 Advert Deadline: August 30th 2015 neW ReSeARCH inTo AeRiAL veHiCLe TeCHnoLo- GieS To enHAnCe PiPeLine MoniToRinG the pipeline infrastructure in canada and the United States is showing growing signs of wear and tear. In the past few months a series of leaks and explosions from Mississip- pi to calgary have led to a number of deaths, damaged property and polluted the local environment. against this background enbridge Pipelines, transcanada corpora- tion and Kinder Morgan canada have signed a Joint In- dustry Partnership agreement to conduct research into aerial-based leak detection technologies with the aim of enhancing pipeline safety throughout North america.the partnership suggests an interest in cutting-edge aerial ve- hicle technology to bolster pipeline safety and reliability. It is also an attempt to answer a chorus of public demands for responsible pipeline development and maintenance. “we are committed to identify, develop and test new tech- nologies to further progress key areas of pipeline safety, such as leak detection. through collaboration with com- mitted industry partners, we continue to make important advancements with leak detection technology,” says Kirk Byrtus, enbridge’s vice President of Pipeline control. “this extension to the Joint Industry Partnership is anoth- er great example of the pipeline industry connecting to make important advancements with leak detection tech- nology, and we look forward to closely working with our partners, transcanada and Kinder Morgan.” diSCoveRy™ CoMPLeTeS SUCCeSSFUL dePLoy- MenT on SHeLL ASSeTS in THe GULF oF MeXiCo Discovery™, the world’s first subsea CT scanner for flowlines, has successfully completed the first deep-water deployment on Shell-op- erated flowlines in the Gulf of Mexico. Discovery™ was developed by tracerco, part of the FtSe100 Johnson Matthey Plc, in response to an industry need for a non-invasive meth- od of scanning subsea flowlines. The technology is used to establish the integrity of subsea pipeline assets. In total, Discovery™ scanned ten flowlines including jumpers, steel catenary risers, and pipe in pipe flowlines all of varying diameters. Over 250 ct scan images over a pipeline length of 50,000 feet, at depths down to 4,200 feet, were generated. In the Gulf of Mexico, based on such data, Shell was able to build a complete profile of their pipeline, which helped to confirm the condition of the asset. Shell undertook a comprehensive technology review to select an inspection solution to support safe, efficient, and competitive oper- ations. Discovery™ offers three key advantages over alternative in- spection technologies: - The device attaches to the outside of the flowline, allowing the in- spection campaign to be conducted while production continues; - There is no need to remove the insulation coating on the flowline, minimising the risk of flowline damage or of the build-up of hydrates; - Scan image data is available in real time, allowing engineers to rap- idly evaluate and respond to any integrity and flow assurance prob- lems. Jim Bramlett, Business Development Manager for tracerco’s Sub- sea technologies division, said: “Using Discovery™ we were able to quickly deliver data, drip feeding the scans through to Shell engi- neers then providing an in-depth analysis once we had all the infor- mation. we understand that for each day a pipeline is out of action, or not performing at peak, there are significant financial implications” the planning, preparation and execution of the inspection campaign was a joint effort which provided access to the Discovery™ CT scan images, and tracerco’s expert interpretation, within the same day. Discovery™ scans pipelines from the outside to gain an accurate picture of the condition of the pipe and the flow, with no need to re- move the protective coating and no interruption to production. It is a highly accurate, rapid and low risk solution to gaining information on flowlines including pipe-in-pipe and bundle systems. Discovery™ provides a 360 degree, high resolution scan of pipeline contents and pipe walls in real time, with defect resolution of 1mm. enbridge, transcanada, Kinder Morgan working together to evaluate aerial-based pipeline safety technologies (© 2015, enbridge Inc.) tracerco Shell deployment in Gulf of Mexico indUSTRy And PRACTiCe 14 PiPeLine TeCHnoLoGy JoURnAL TeCHniP’S SUBSidiARy TiPieL AWARded A ConTRACT FoR A neW GAS PiPeLine in PeRU tipiel(1) S.a., technip’s subsidiary in colombia, was awarded by the consorcio constructor Ductos del Sur(2), a front-end engineering de- sign and detailed engineering design contract, on a lumpsum basis. this covers the development of a new gas pipeline to transport gas from the Camisea field to Southern Peru. launched by the Peruvian government, the project consists of more than 1,700 kilometers of 32” gas pipeline. It aims to improve the exist- ing Peruvian energy Network, contributing to the development of an energy Node and Petrochemical hub in Southern Peru. The overall work will be performed by Tipiel’s offices in Bogota, Co- lombia. Marco villa, technip’s Region B(3) President, commented: “This award reflects the importance to accompany the client since the very early stage of an initiative to help design an optimized pro- ject execution scheme.” Riccardo Nicoletti, tipiel General Manager, stated: “this contract, which is related to one of the most important projects for the devel- opment of energy infrastructure in Peru, serves our objective to make tipiel a leading engineering company outside colombia as well”. SHAWCoR AnnoUnCeS ConTRACT To PRovide PiPe CoATinG SeRviCeS FoR THe GneA PRoJeCT in ARGenTinA Shawcor ltd. (tSX:Scl) today announced that its pipe coating divi- sion has received two contracts for approximately US$55 million from tenaris to provide three layer polyethylene anti-corrosion pipeline coatings for the first and second phase of the Argentina Northeast Gas Pipeline (GNea) project. this project is owned by eNaRSa, an argentine state-run energy com- pany, and it includes the construction of a gas pipeline that will trans- port up to 11,200,000 m³/day of natural gas to locations in northeast argentina. the execution of these contracts has commenced in Shawcor’s coat- ing facilities in argentina and is expected to be completed by Q1 2016. For further information: Shawcor ltd.Gary love vice President, Finance and cFO tel: 416-744-5818 e-mail: glove@shawcor.com website: www.shawcor.com XCeL eneRGy WiLL USe dRone TeCHnoLoGy To PRoTeCT And iMPRove eneRGy ReLiABiLiTy And SAFeTy FAA approves company’s request to use unmanned aircraft for energy infrastructure inspections Xcel energy inspects more than 320,000 miles of electricity and nat- ural gas infrastructure to ensure the safety and reliability of its ener- gy system. Now with approval of the Federal aviation administration, Xcel Energy will be able to more efficiently, effectively and safely mon- itor its systems using drone technology. the Faa on May 11 approved Xcel energy’s request to operate small unmanned aircraft systems or drones commercially. Xcel energy sought the approval so it can inspect its critical energy infrastructure. Xcel energy will use drones to visually inspect electricity transmission and distribution lines, power plants, renewable energy facilities, sub- stations and natural gas transmission and distribution pipelines. “we are pleased with the Faa decision as we study how this new tech- nology can best be used to enhance employee and public safety at our operations,” said Kent larson, Xcel energy’s executive vice president and group president of operations. the use of small unmanned aircraft systems will allow Xcel energy em- ployees to safely inspect hard to reach areas, keeping the workers out of danger. employees will also use drones to observe environmentally sensitive areas without the use of trucks, helicopters or other utility equipment, minimizing the environmental impact. “we believe these measures will increase electricity and gas system re- liability, reduce customer costs and improve our emergency response times,” said larson. he added that the company’s current plan is to use drones only over utility property or utility rights of way and away from populated areas and airports. The drones will be flown at low altitudes and in the operator’s line of sight. the Xcel Drone INDUSTRY AND PRACTICE PiPeLine TeCHnoLoGy JoURnAL 15 PIPELINE TECHNOLOGY CONFERENCE eXHiBiToRS50+deLeGATeS 500+ “63% of the PTC Delegates are coming from abroad (Europe, Middle East, North America, South America, Asia, etc.)” The Pipeline Technology Conference (ptc), europe’s leading pipeline conference and exhibition, the Pipeline Technology Conference (ptc), will take place for the 10th time offering again opportunities for operators as well as technology and service providers to exchange latest technologies and new developments supporting the energy strategies world-wide. The conference will provide panel discussions and special focus sessions on “Pipeline Safety”, “German energy Turnaround”, “Challeng- ing Pipelines” and “Offshore Technologies”. For the first time the conference will also feature an “Scientific Advances Poster Session” with latest updates on present and upcoming research activities. ptc will feature lectures and presentations on all aspects surrounding oil, gas, water and product pipeline systems. The exhibition with more than 50 exhibitors will show latest pipeline technologies and products. For more information kindly visit: www.pipeline-conference.com diFFeRenT nATionS55+ 16 PiPeLine TeCHnoLoGy JoURnAL PIPELINE TECHNOLOGY CONFERENCE eURoPe’S BiGGeST PiPeLine evenT THe AnnUAL GATHeRinG oF THe inTeRnATionAL PiPeLine CoMMUniTy in THe HeART oF eURoPe After starting as a small side event of the huge HAnnoveR MeSSe trade show in 2006 in Hannover, the Pipeline Technology Conference developed into europe’s largest pipeline confer- ence and exhibition. Since 2012 the eiTeP institute organizes the ptc on its own and moved the event to Berlin in 2014. The 10th anniversary will again be a record breaking event. 10th A N N IV E R S A RY technical Sessions at ptc 2015 Integrity Management Geohazards construction Materials challenging Pipelines Inline Inspection Repair / Rehabilitation Management Pump & compressor Stations leak Detection Monitoring coating Offshore Technologies diFFeRenT nATionS SUPPoRTeRS35+ 13 PiPeLine TeCHnoLoGy JoURnAL 17 PIPELINE TECHNOLOGY CONFERENCE PiPeLine TeCHnoLoGy ConFeRenCe ptc this “German” international conference is organized by eIteP (euro Institute for Infor- mation and technology transfer in environ- mental Protection), based in hanover. It is es- pecially supported by the major gas network operators (as to content) and by producers and service providers from europe (exhibi- tors). content-related matters are managed by the internationally staffed 32-member advisory committee, adco. the adco is particularly active when it comes to putting together the conference program. adco members sub- mit the received presentation proposals to a quality check, in which both the content (ab- stracts) and the potential speakers (cvs) are evaluated according to such criteria as rele- vance and topicality. Over 150 proposals for 50 “free” presenta- tions for the Ptc 2015 were received by the eIteP following a “call for Papers”. the “call for Papers” was sent out to about 22,000 verified addresses from the international pipeline community in July 2014. the returns were then examined together with the adco in the manner described. this process ensures that participants are of- fered a high-quality program that addresses and presents for discussion all current and ongoing developments throughout the world. Pipeline construction is booming worldwide – except in Europe. Instead, Europe can offer a lot of experience and technology for opera- tions and maintenance as well as on issues of safety and long service life. that is os- tensibly what participants from asia, africa, australia and North and South america are looking for in europe at the ptc. For the ptc 2015, the presentation selection procedure for the 50 free presentations, which is supplemented by about 10 invited speakers, has resulted in one plenary session and 13 technical sessions with 3 to 5 individ- ual presentations. they cover all important, complex current issues related to the tech- nology of onshore and offshore pipelines. Due to high demand, the topics of “Inline Inspection”, “Geohazards” and “Microbiologi- cally Influenced Corrosion” will be offered as two-day seminars for additional information following the conference. 15 research institutes from academia and in- dustry are taking advantage of the opportuni- ty to present their latest research results in a structured poster show. two particularly topical issues will be ad- dressed in discussion forums. this year, the topics will be: 1. “Pipeline safety” and 2. “the German energy transition”. Both topics will be moderated by the former ceO of Open Grid europe, heinz watzka, who has invit- ed experts from North america and europe to participate in the discussion. DvGw vice President Dr. hüwener will be involved in discussion round 1 and DvGw chairman Dr. linke in discussion round 2. this will ensure that there will be plenty of input into various aspects of the German gas industry. the papers from the past 9 years of ptc are made freely available in a central abstract/ paper database for research purposes at: www.pipeline-conference.com. one of the world’s major pipeline conferences will be held from June 8-10, 2015 in Berlin. With 500 to 600 participants from about 50 countries, the international Pipeline Technology Conference (ptc) is already among the largest and most important conferences of its kind in the world just 10 years after being initiated. Play video 18 PiPeLine TeCHnoLoGy JoURnAL PIPELINE TECHNOLOGY CONFERENCE Berlin is more than 775 years old and over the decades, all gener- ations have left their monuments and landmarks in town.the cap- ital is a centre for international conventions and trade fairs and the number one among German cities for conventions. Berlin offers excellent infrastructure, the most up-to-date locations in europe, a diverse range of services and a great shopping mile and night-life. Berlin is a world city of culture, politics, media, and science. Its econ- omy is based on high-tech firms and the service sector, encompass- ing a diverse range of creative industries, research facilities, media corporations, and much more. Berlin serves as a continental hub for air and rail traffic and has a highly complex public transportation network. The metropolis is a popular tourist destination. Significant industries also include It, pharmaceuticals, biomedical engineering, clean tech, biotechnology, construction, and electronics. Berlin is one of the 16 states of Germany with a population of 3.5 million peo- ple. It is also the country’s largest city. the international PtC Community meetS in berlin Combine your ptc visit with Berlin sightseeing PiPeLine TeCHnoLoGy JoURnAL 19 PIPELINE TECHNOLOGY CONFERENCE Attendees networking at the exhibit i o n Plenary sessions during ptc Lively and interesting discussions Boat-Trip: “Dinne r a t N i g h t ” Over 400 Attendees visit e d p t c 2 0 1 4 i n B e r l i n ptc 2014Impressions from in Berlin See you at ptc 2015 www.pipeline-conference.com CLIENT: GENERAL ELECTRIC PRODUCT: Predictivity Trade Ads - Oil & Gas JOB#: P46148 SPACE: full page 4C BLEED: 8.25” x 11.125” TRIM: 8” x 10.5” SAFETY: 7” x 9.5” GUTTER: None PUBS: Oil & Gas Journal ISSUE: None TRAFFIC: Mary Cook ART BUYER: None ACCOUNT: Joslyn Dunn RETOUCH: None PRODUCTION: Michael Musano ART DIRECTOR: Fernando Mattei COPYWRITER: None This advertisement was prepared by BBDO New York Fonts GE Inspira (ExtraBold, Regular) Graphic Name Color Space Eff. Res. 140926_GE_Data_Pipelines_Final_4_CMYK.psd (CMYK; 355 ppi), GE_ GreyCircles_LogoOnLeft_Horiz.ai, ACC_hpd_logo_.75x_white_cmyk. eps Filename: P46148_GE_ITL_V3.indd Proof #: 3 Path: Studio:Volumes:Studio:MECHANIC..._ Mechanicals:P46148_GE_ITL_V3.indd  Operators: Danna, Sherry / Danna, Sherry Ink Names Cyan Magenta Yellow Black Created: 2-7-2013 4:10 PM Saved: 9-26-2014 3:11 PM Printed: 9-26-2014 3:12 PM Print Scale: None Redefining Pipeline Operations. Identifying issues early is the key to making proactive decisions regarding pipeline safety, integrity and effi ciency. The Intelligent Pipeline Solution, with Pipeline Management from GE PredictivityTM software and Accenture’s digital technology, business process and systems integration capabilities, works across your pipeline system to turn big data into actionable insights in near real-time. When GE and Accenture speak the language of analytics and change management, managers can make better decisions with more peace of mind. intelligentpipelinesolution.com S:7”S:9.5”T:8”T:10.5”B:8.25”B:11.125”20 PiPeLine TeCHnoLoGy JoURnAL CLIENT: GENERAL ELECTRIC PRODUCT: Predictivity Trade Ads - Oil & Gas JOB#: P46148 SPACE: full page 4C BLEED: 8.25” x 11.125” TRIM: 8” x 10.5” SAFETY: 7” x 9.5” GUTTER: None PUBS: Oil & Gas Journal ISSUE: None TRAFFIC: Mary Cook ART BUYER: None ACCOUNT: Joslyn Dunn RETOUCH: None PRODUCTION: Michael Musano ART DIRECTOR: Fernando Mattei COPYWRITER: None This advertisement was prepared by BBDO New York Fonts GE Inspira (ExtraBold, Regular) Graphic Name Color Space Eff. Res. 140926_GE_Data_Pipelines_Final_4_CMYK.psd (CMYK; 355 ppi), GE_ GreyCircles_LogoOnLeft_Horiz.ai, ACC_hpd_logo_.75x_white_cmyk. eps Filename: P46148_GE_ITL_V3.indd Proof #: 3 Path: Studio:Volumes:Studio:MECHANIC..._ Mechanicals:P46148_GE_ITL_V3.indd  Operators: Danna, Sherry / Danna, Sherry Ink Names Cyan Magenta Yellow Black Created: 2-7-2013 4:10 PM Saved: 9-26-2014 3:11 PM Printed: 9-26-2014 3:12 PM Print Scale: None Redefining Pipeline Operations. Identifying issues early is the key to making proactive decisions regarding pipeline safety, integrity and effi ciency. The Intelligent Pipeline Solution, with Pipeline Management from GE PredictivityTM software and Accenture’s digital technology, business process and systems integration capabilities, works across your pipeline system to turn big data into actionable insights in near real-time. When GE and Accenture speak the language of analytics and change management, managers can make better decisions with more peace of mind. intelligentpipelinesolution.com S:7”S:9.5”T:8”T:10.5”B:8.25”B:11.125” PTC-PoSTeRSHoW This paper will be presented during the “Scientific Advances Poster Session” at 10th Pipeline Technology Conference HiGH indUCTive interference on pipelines due to nearby high voltage overhead lines RESEARCH / DEVELOPMENT / TECHNOLOGY PiPe Line voLTAGe PoSSiBLe ReASonS WHy CALCULATionS oF indUCTive inTeRFeRenCe PiPeLine voLTAGeS ARe HiGHeR THAn CondUCTed MeASUReMenTS Due to bundled energy routes, high voltage energy systems (hveSs), e.g. overhead lines or ac traction power supply systems, are often lo- cated near buried isolated metallic pipelines. thus, a possible high in- ductive interference from energy systems may produce hazardous ac pipeline interference voltages (PIvs). high induced voltage levels can cause dangerous high touch voltages (personal injuries) and damag- es to pipeline system components (overvoltage, ac material corrosion). therefore, for minimizing the risk of personal injuries and material cor- rosion, european standards and guidelines (eN 50443 [1], eN 15280 [2]) exist which limit the maximum voltage for long term and short term in- terference If the PIv is within given limits, the risk for personnel and ma- terial is acceptable and no further measures, e.g. ac earthing systems, special working methods or additional isolating joints along the pipeline are required and no further mitigation costs are generated. For this reason it is necessary to calculate the induced PIvs already in the planning stage or in the case of significant changes in the pipeline or hveSs to specify necessary protection measures, particularly in are- as where the PIv is already near the given limit. Unfortunately, the results of these – standardized – calculations are of- ten up to 7 times higher than conducted measurements on pipelines, despite using state of the art calculation parameters. Research on this discrepancy is needed to bring calculations and measurement data closer together to avoid excessive measures. abstract > by: Christian Wahl > and: Ernst Schmautzer > Graz University of Technology Institute of Electrical Power Systems PiPeLine TeCHnoLoGy JoURnAL 23 RESEARCH / DEVELOPMENT / TECHNOLOGY indUCTive inTeRFeRenCe on PiPeLineS Inductive coupling appears when a magnetic field between an in- terfered buried isolated metallic pipeline system and an interfering HVES exists. The inductive coupling impedances ▁z_gkL are affected by all of the below-described parameters and can be calculated with e.g. the formula of Dubanton [3]. these hveS parameters are load current or phase conductor ar- rangement as well as pipeline parameters such as the pipeline di- ameter, material or coating. another parameter is the ambience soil resistivity which varies within a large spectrum. The final important parameter is the influence of several known and unknown grounded conductors, located near influenced or influencing systems. These conductors produce a voltage reduction on the induced pipeline and can be e.g. the PeN conductor of low voltage power lines, metal rails and compensation conductors of ac traction power supplies, con- ducting pipelines, foundation earth electrodes and global earthing systems. the induced voltage Ui can be calculated by formula (1). If all currents and inductive coupling impedances zgkl for one seg- ment l are known, the induced voltage Ui can be calculated for a seg- ment. Segmenting is needed because the geographical closeness and other parameters are not constant over the whole interfering dis- tance and therefore the value of zgkl is always changing see Figure 1. Also, other segments are not influenced as shown in Figure 1. When all induced voltages Ui have been determined, the induced PIv over the whole interfering distance is calculated with the lattice network model. as a requirement for using this model, all parameters must be (approximately) homogenous within one segment. the parameters in this network model represent the longitudinal impedance (Rl, ll), which stands for the pipeline material charac- teristics and the shunt admittance (cQ, RQ), which is a combina- tion of the pipeline coating value, ambience soil resistivity, reduc- tion conductors and reducing earthing systems. the PIv alongside the pipeline can be calculated with the node admittance matrix [4]. diFFeRenT PoSSiBLe iMPACT FACToRS on PiPeLine voLTAGeS The following factors are suspected of having different degrees of impact on the induced voltages and the discrepancy between calcu- lated and measured PIvs and has to be considered individually and in combination with each other: • load current instead of using the maximum operational cur- rents • Reduction effect of global earthing systems • Reduction effect of practically achievable pipeline earthing systems • Reduction effect of pipelines, running in parallel • Reduction effect of parallel high voltage power systems with grounding conductors • Reduction effect of local earthing systems • Incorrect or inadequate pipeline coating parameter • The influence of the model-conform specific soil resistivity Lattice network modell for the pipeline Earth Ik Interfered area Segment 2 Interfered area Segment 3 Not interfered area Segment 1 LL R RLRLLLL LL Induced voltage U RQ2RQ2RQ2RQ2RQ2RQ2CQ/2CQ/2CQ/2CQ/2CQ/2CQ/2i1 Distance of parallel route l1 Induced voltage Ui2 Distance of parallel route l2 ZgkL1 ZgkL2 U1 U2 U3 U4 Ik: High voltage energy system with interfering currents U1...4: Pipeline interference voltage alongside the pipeline Ui1...i2: Induced voltage ZgkL1...2: Inductive coupling impedance Ik Figure 1: Pipeline subdivided into segments because of changing parameters 24 PiPeLine TeCHnoLoGy JoURnAL RESEARCH / DEVELOPMENT / TECHNOLOGY iMPACT oF THe LoAd CURRenT as stated above, the value of the load current is a direct proportionality factor in the voltage calculation formula (1). Normally it is common prac- tice to use the maximum operational currents in order to cover worst case scenarios for touch voltages or, depending on the type of the influ- encing system, 60 to 95 percent of this maximum load current for ac corrosion. In reality, these operational currents rarely occur. For the comparison of a one week lasting measurement and its associated calculations on the same pipeline locations it is indispensable to use the correct actually used load currents to get comparable results. The difference between such currents and maximum operational currents is illustrated for an overhead line and a railroad system in Figure 2 [5]. PoSSiBLe voLTAGe RedUCTion eFFeCT oF GeSS, HveSS And PiPeLineS - GLoBAL eARTHinG SySTeMS (GeSS) In short, GeSs consist of connected foundation electrodes and other conductive material buried in the soil within a (sub-) urban area. this connection can be realised intentionally or unintentionally either direct- ly via conductive materials or in the common sense via the electric flow field. If an HVES is located near a pipeline and a GES, a configuration arises as depicted in Figure 3. 0 200 400 600 800 1000 1200 1400 1600 1800 2000 2200 2400 0 20 40 60 80 100 120 140 160 Current in Ampere Time in Hours Maximum operational current Overhead Line, actually used load currents Railroad, actually used load currents Soil Zpipe Zearth GES of a (sub-)urban area High voltage overhead line Foundation electrode from a house in 1 m depth Current I Ypipe Yearth 1 m depth Earth wire current Iew Inductive coupling Z Ohmic coupling Y Ype Zpe Induced current Ipipe Part of the GES current Iearth Buried isolated metallic pipeline in 1 m depth Figure 2: Difference between maximum operational currents and load currents for overhead lines Figure 3: the complex interference and reduction situation between high voltage power line, GeS and pipeline system PiPeLine TeCHnoLoGy JoURnAL 25 RESEARCH / DEVELOPMENT / TECHNOLOGY In these cases, pipeline and GeS are more or less parallel metallic conductors due to their similar conductive material. the inductive coupling impedances zgkl. from the energy system turn into a par- allel connection of the pipeline coupling zpipe. and the GeS coupling zearth. consequently, the coupling impedance to the pipeline is re- duced with the effect of a lower PIV. Thus, GESs have a reduction effect. How great it is depends on the expansion, grid structure as well as the material- and soil-conductivity. as a result of the induc- tive coupling, the pipeline voltage Ui is induced with consideration of this reduction effect. This leads to the currents Ipipe and Iearth . these currents result in an additional inductive coupling zpe., additionally increasing or reducing the current Ipipe and thus the PIv [5]. the following calculation example shows the impact of such interfer- ence between an HVES, a pipeline and three differently sized GESs. GeS 1 and 2 represents a village with a low and GeS 3 a small city with a medium density of conducting grounded material. the size and the amount of buried conducted metal leads to an accordingly high volt- age reduction effect. Also, the general geographical alignment, e.g. distance between the systems or position along the pipeline, is im- portant. As depicted in Figure 4 the PIV calculation shows different reduction effects from the differently sized GESs. Since GES 1 (red line) and 3 (purple line) have a similar reduction effect, it can be seen that the geographical alignment is important. GeS 1 is in the middle of the pipeline and the reduction effect evenly distributed over the entire PIv. Because GeS 3 lies on the end of the pipeline, it has a notable PIV reduction effect especially in this area. Due to of the bigger size of the GES 2 (green line), a remarkable voltage reduction effect can be seen which shows that GeSs has to be considered in calculations. oTHeR PiPeLineS Because of bundled energy routes, transport pipelines are built near other pipelines. therefore two or more pipelines can run parallel over a long distance. If an HVES is located near a configuration with two pipelines, a setup appears as can be seen in Figure 5 and two inter- ference effects have to be noted. The first effect is due to the inductive coupling between the HV power line and the pipeline causing currents in both pipelines. Depending on the current flow direction, the current Ipipe2 can increase or reduce the current Ipipe1 and vice versa. Figure 5 shows an example, where both currents flow in the same direction. The second effect is based on the fact that the second pipeline (blue) works as a reduction conductor (see chapter 2.2.1) on the regarding pipeline (red). this means that both factors have to be considered to be able to state whether the pipeline current and interference voltage is increased or reduced. Figure 6 illustrate how this reduction or increasing factor from a par- allel pipeline works. It shows three different calculations which depict the influence of the current directions on the regarding PIV. The blue line shows the calculation of the PIv of the regarding pipeline with- out any other parallel pipeline; the other two lines already include the parallel pipeline reduction effect. This shows that when both pipeline currents flow in the same direction, the regarding pipeline current and therefore, the PIv, are increased (green line). Furthermore, it is clearly shown that a reduction effect is present when the currents flow in opposite directions (red line). Figure 4: PIV reduction effect from differently sized GESs 0 5 10 15 20 25 0 0,5 1 1,5 2 2,5 3 3,5 Pipeline Voltage in Volt Pipeline distance in km Pipeline without GES interference Pipeline with GES 1 interference Pipeline with GES 2 interference Pipeline with GES 3 interference 26 PiPeLine TeCHnoLoGy JoURnAL RESEARCH / DEVELOPMENT / TECHNOLOGY 0 5 10 15 20 25 30 0 0,5 1 1,5 2 2,5 3 3,5 Pipeline Voltage in Volt Pipeline distance in km Pipeline voltage without any other pipeline Pipeline with reduction effect of parallel pipeline Pipeline with amplifing effect of parallel pipeline Soil Zpipe1 Zpipe2 High voltage overhead line Current I Ypipe1 Ypipe2 1 m depth Earth wire current Iew Inductive coupling Z Ohmic coupling Y Ypp Zpp Induced current Ipipe1 Buried isolated metallic pipeline in 1 m depth Induced current Ipipe2 Figure 5: the complex interference and reduction situation between high voltage power line and two pipeline systems Figure 6: PIv with a second parallel pipeline PiPeLine TeCHnoLoGy JoURnAL 27 RESEARCH / DEVELOPMENT / TECHNOLOGY PARALLeL HiGH voLTAGe eneRGy SySTeMS especially, high voltage power lines but also railway systems are bun- dled on energy routes and therefore often have a long parallel rout- ing. this leads to potentially high inductive interference. Besides the geographical alignment and HVES parameters, the load flow current situation is crucial. In case of the same load flow current in parallel hveSs, the pipeline inductive interference voltage rises dramatically. If the load currents flow in different directions, the PIV is massive- ly lower. The overall load flow situation should always be reviewed when comparing measurement data with calculation results. LoCAL eARTHinG SySTeMS local earthing systems are conducted materials, e.g. connecting wa- ter pipelines or earthed cable shields, buried in the soil. They are diffi- cult to detect and usually not considered in calculations but can still act as reduction systems in the vicinity of hveSs and pipelines. this can lead to unexplainable reduced PIVs since the physical effects and the calculations are very similar to the above-mentioned cases. oHMiC-indUCTive CoUPLinG an ohmic coupling Y exists between all interfered and interfering systems due to their earthing systems. In normal and fault operation conditions of HVESs, earth currents can flow through their earthing systems (e.g. pylons or transformer stations) into their ambience soil and, in the vicinity of a GeS, pipeline or other conductive material, they can catch these currents and spread them to other regions. this results in a higher Iearth component with the effect of a higher influ- ence on the current Ipipe and the resulting PIv. inCoRReCT oR inAdeqUATe PiPeLine CoATinG PARAMeTeR It is generally known that the pipeline coating is crucial to avoid ma- terial corrosion. It is problematic that the value of the coating resist- ance can vary within a wide range. On the one hand, the material has been changed from bitumen with a low value (1 MΩm) to polyethyl- ene with a high value (100 MΩm). One the other hand, with time, the resistance value can fall to 10 kΩm (bitumen) or 50 kΩm (polyeth- ylene) due to coating holidays. to summarise, with a lower coating resistance value, a lower PIv can be expected which one should bear in mind when comparing measurements and calculations [6]. vARyinG THe SPeCiFiC SoiL ReSiSTiviTy The soil resistivity has a very strong influence on the PIV (as is shown in the paper of 2014 [6]). In areas with lower values, lower PIvs can be expected. However, weather and time of the year also influence the soil resistivity, changing the soil moisture and the soil temperature. the soil resistivity is lower when the soil moisture is high (e.g. due to high precipitation) and/or the soil temperature is high (e.g. during the summer). Therefore it is difficult to find the correct value of the soil resistivity along a pipeline. Generally, the specific soil resistivity ranges between 25 Ωm and 10000 Ωm. Based on this wide range of values and the fragmenting of the different types of soil, the value for the representative respec- tive ambient soil resistivity along the pipeline can be very diverse. considering this variation is essential, both for calculations and measurements. especially where measurements are conducted a de- tailed soil analysis is indispensable. 0 0,5 1 1,5 2 2,5 3 3,5 4 4,5 5 0 20 40 60 80 100 120 140 160 Pipeline Voltage in Volt Time in Hours Calculation without reduction factors Measurement PRACTiCAL ReSULTS The following figures show different examples of calculations using the actually used load currents and comparing them to measure- ments during a measurement period of 140 to 160 hours at different pipeline locations. Figure 7 shows a nearly identical voltage charac- teristic between measurement and calculation since the model pa- rameters reflect the real conditions very well. The calculations in Figures 8 and 9 (which represent two different locations) without reduction effects show results higher by a factor of up to 7, compared to calculations considering conductive material nearby. These two figures show an intense voltage reduction, based on the geographical closeness of two different things: in location 2, another pipeline in combination with the reduction factor of two par- allel high voltage overhead lines and in location 3, a rural area with a well-developed and extended GeS. Figure 7: PIv calculation versus measurement, location 1, perfect example 28 PiPeLine TeCHnoLoGy JoURnAL RESEARCH / DEVELOPMENT / TECHNOLOGY 0 1 2 3 4 5 6 7 8 9 0 20 40 60 80 100 120 140 160 Pipeline Voltage in Volt Time in Hours Calculation without reduction factors Calculation with reduction factors Measurement 0 2 4 6 8 10 12 14 16 18 20 0 20 40 60 80 100 120 140 160 Pipeline Voltage in Volt Time in Hours Calculation without reduction factors Calculation with reduction factors Measurement Figure 8: PIv calculation versus measurement, location 2, hveS Figure 9: PIv calculation versus measurement, location 3, railway Figures 10 and 11 show a combination of two reduction effects: the volt- age reduction effect due to a parallel pipeline and also a voltage shift due to inadequate soil resistivity. Apart from the reduction effect, in lo- cation 4 the specific soil resistivity was essentially lower than expected while in location 5, the value was higher. Figure 10 because the calcula- tion result is massively lower than before while in Figure 11, the average value is still remaining on the same level with consideration of the par- allel pipeline reduction effect. PiPeLine TeCHnoLoGy JoURnAL 29 RESEARCH / DEVELOPMENT / TECHNOLOGY 0 0,5 1 1,5 2 2,5 3 3,5 4 0 20 40 60 80 100 120 140 160 Pipeline Voltage in Volt Time in Hours Calculation without reduction factors Calculation with reduction factors Measurement 0 2 4 6 8 10 12 14 0 20 40 60 80 100 120 140 160 Pipeline Voltage in Volt Time in Hours Calculation without reduction factors Calculation with reduction factors Measurement Figure 10: PIv calculation versus measurement, location 4, parallel pipeline with low soil resistivity Figure 11: PIv calculation versus measurement, location 5, parallel pipeline with high soil resistivity References EN 50443:2012, “Effects of electromagnetic interference on pipelines caused by high voltage a.c. electric traction systems and/or high voltage a.c. power supply systems”, ceNelec, Brussels eN 15280:2013, “evaluation of a.c. corrosion likelihood of buried pipelines applicable to cathodically protected pipelines”, ceNelec, Brussels c. Dubanton, 1970, “calcul approche des parameters primaires et secondaires d’une ligne detransport. valeurs homopolaires”, cIGRe E. Schmautzer, 1991, “Ein Beitrag zur Berechnung der niederfrequenten induktiven Beeinflussung von Rohrleitungsnetzen”, Disser- tation, Graz University of technology, Graz, austria c. wahl, 2015, “Impact of Global earthing Systems on the Inductive Interference on Buried Isolated Metallic Pipelines”, 23nd Interna- tional conference on electricity Distribution, lyon, France c. wahl, 2014, “Impact of high voltage Overhead lines on Pipeline Security”, 9th Pipeline technology conference, Berlin, Germany 30 PiPeLine TeCHnoLoGy JoURnAL RESEARCH / DEVELOPMENT / TECHNOLOGY SUMMARy even if calculations are done very carefully with established and gener- ally agreed calculation methods, conducted measurements show most- ly lower voltage levels than the calculated ones for the same pipelines and pipeline locations. With the consideration of the reduction – or even increasing – effects presented in this paper, most of the discrepancies between measurement and calculation can be explained when all im- portant parameters are known. Knowledge of the correct specific soil resistivity and pipeline coating resistance is a precondition since both parameters can influence the PIv in the measuring position. the value of the load currents during the measurement period must be known, as it is essential to correctly inter- pret the measurement data. Much more complicated are conducted ma- terials within the interference area because they can act as a reduction factor, decreasing PIVs. They can also produce influencing voltages and in an unfavourable case, may even increase PIvs too. The examples show that with consideration of all presented effects, most of the conducted measurements can be explained and even bet- ter, they can help to calibrate the calculation. with this research it is pos- sible to reduce or avoid unnecessary measures while necessary actions, e.g. ac earthing systems or special safety working methods along the pipeline, can be used more effectively and efficiently. Christian Wahl Graz University of technology Institute of electrical Power Systems Graz, austria christian.wahl@tugraz.at ernst Schmautzer Graz University of technology Institute of electrical Power Systems Graz, austria schmautzer@tugraz.at Authors OUTSTANDING PROTECTION www.denso.deGermanymade in since 1922 ■ Proven corrosion protecting technology for more than 40 years ■ 3-ply tape technology! No risk of spiral corrosion compared to 2-ply tapes ■ Compatible with mill coatings from PE, PP, FBE, PU, CTE and Bitumen PiPeLine TeCHnoLoGy JoURnAL 31 RESEARCH / DEVELOPMENT / TECHNOLOGY SeiSMiC AnALySiS oF BURied STeeL PiPeLine SUBJeCTed To GRoUnd deFoRMATion WiTH eMPHASiS on THe nUMeRiCAL ModeLLinG oPTiMiZATion buried STeeL > by: Gersena Banushi, Technische Universität Braunschweig, Germany and Università di Firenze, Italy 32 PiPeLine TeCHnoLoGy JoURnAL RESEARCH / DEVELOPMENT / TECHNOLOGY Steel pipeline systems traverse large geographical areas characterized by a wide variety of soil conditions and environmental hazards such as earthquakes which can threaten the pipeline integrity undergoing large deformations associated with widespread yielding, leading to fracture with consequent material leakage. Buried pipelines installed in seismic regions are susceptible to the ef- fects of transient ground deformation (tGD) due to seismic wave prop- agation and permanent ground deformation (PGD) resulting from earth- quake induced soil liquefaction, surface faulting and landslides [1]. Post-earthquake investigations have shown that almost all seismic damages to buried pipelines were due to permanent ground deforma- tion and there were very few reported cases of pipelines damaged only by wave propagation [2]. In fact, buried pipelines are primarily affected by large permanent ground deformations (PGD) which may produce pipe wall rupture due to excessive tension as well as buckling by either excessive imposed bending or uniaxial compression loading. Therefore it is necessary to perform accurate finite element analysis taking into account the nonlinear soil and pipe interaction as well as the constitutive behavior of the pipe material subjected to extreme seismic loading. At the state of art, detailed finite element analysis of the soil-pipeline system subjected to large ground deformations are computationally expensive resulting in extremely large numerical models that may re- quire days to run using the normally available computational resources [3]. within the present work, in order to reduce the needed memory and computation time of the calculator, the part of the soil-pipe system away from the fault is suitably modeled as a single equivalent axial spring, connected to the pipe shell elements through appropriate constraints. Furthermore, the seismic performance of the buried pipeline has been investigated through a series of parametric studies that permit to as- sess the structural response of the pipe components in function of var- ious configurations of the soil-pipeline system. The obtained numerical analysis results allow to evaluate accurately the limit ground displace- ment inducing global failure on the pipeline components due to loss of strength capacity following large scale seismic loading, with the advan- tage of being computationally efficient. “PoST-EArThqUAkE INvESTIGA- TIoNS hAvE ShowN ThAT AlMoST All SEISMIC DAMAGES To BUrIED PIPElINES wErE DUE To PErMA- NENT GroUND DEForMATIoN” > Gersena Banushi abstract PTC-PoSTeRSHoW This paper will be presented during the “Scientific Advances Poster Session” at 10th Pipeline Technology Conference PiPeLine TeCHnoLoGy JoURnAL 33 RESEARCH / DEVELOPMENT / TECHNOLOGY nUMeRiCAL ModeLinG within the present study the seismic performance of a straight 36’’ x 9.53 mm X65 steel grade pipeline subjected to strike-slip faulting has been assessed through accurate finite element analysis taking into account the nonlinearities of the pipe-soil system, with emphasis on identifying the pipeline structural failure. the buried steel pipeline is modeled a cylindrical shell using four- node reduced integration shell elements (S4R) available in aBaQUS (2014) [4] which account for finite membrane strains and arbitrarily large rotations, resulting suitable for large strain analysis. the soil surrounding the pipeline is discretized through eight-node linear brick continuum elements with reduced integration (c3D8R). the steel pipe material model is defined within the von Mises plastici- ty theory with nonlinear hardening. Instead, the soil material is de- scribed within the Mohr–Coulomb constitutive model, characterized by different parameters, like the cohesion, the friction and dilatation angle, the elastic modulus e, and Poisson’s ratio v, as indicated in the table 1. the soil-pipeline interaction is assumed as frictional allowing for sliding and separation at the soil-pipe interface. As schematically illustrated in the figure 1, the vertical plane contain- ing the fault trace divides the soil in two equal antisymmetric parts. the fault movement is applied as a horizontal displacement of the lateral external faces of the moving soil part whereas the lateral ex- ternal faces of the fixed part are restrained in the horizontal direction. Instead the faces of the bottom boundary of both soil parts are re- strained to move in the vertical direction. Moreover, it is noted that each of the ends of the shell pipeline is connected through appropriate constraints to an equivalent bound- ary spring, which represent the reaction of the part of the soil-pipe- line system away from the fault to the pipeline displacement, as de- scribed in detail in the following paragraph. The mesh of both the soil and pipeline components is refined in the central region, close to the fault trace, in order to better capture the large deformation behaviour of the system. the numerical simulations for assessing the pipeline performance subjected to strike-slip fault movement are conducted in two steps. At first, a geostatic analysis is performed to establish the initial stress and strain state of the soil-pipeline system, which equilibrates the gravity loading and satisfies the boundary conditions. In the second step, a uniform horizontal displacement is applied at the lateral exter- nal faces of the moving soil part and the free end of the correspond- ing equivalent boundary spring, whereas the lateral external faces of the fixed soil part, as well as the free end of the corresponding equiv- alent boundary spring remain restrained in the horizontal direction. CALiBRATion oF THe eqUivALenT BoUndARy SPRinG. Observing that the relative transverse displacement between the soil and the pipe segment away from the fault trace is negligible, this part is suitably modelled as a single equivalent axial spring connected to the pipe shell elements through appropriate constraints, assuring the deformation continuity of the system, as schematically illustrated in the figure 2. The force displacement relationship of the equivalent axial spring is obtained analytically taking into account the axial con- stitutive behaviour of the pipeline as well as of the axial soil-pipeline interaction. the latter is obtained by subjecting the pipeline statically to a uniform axial displacement, after establishing the initial geostat- ic stress-strain state in the system, as schematically illustrated in the figure 3. the obtained axial spring constitutive behavior is subsequently im- plemented in ABAQUS [4] finite element software for the numerical analysis purposes. this modeling procedure permits to largely reduce the memory and computation time of the calculator, compared to the one where the entire length of the pipeline is modelled with nonlinear shell elements and the surrounding soil with solid elements. Soil cohesion Friction angle o Young’s Modulus e Poissson’s ratio v Soil density y 50 kPa 0 25 mPa 0.48 20 kN/m3 clay Soil table 1. Mechanical characteristics of the soil analysed. Figure 1. Schematic representation of the soil pipeline system subjected to strike-slip faulting. Figure 2. Schematic representation of the equivalent- boundary spring model 34 PiPeLine TeCHnoLoGy JoURnAL RESEARCH / DEVELOPMENT / TECHNOLOGY considering the axial constitutive behaviour of the pipeline, as well as the axial soil-pipeline interaction, as schematically illustrated in the fig- ure 4, the relationship between the equivalent spring axial force F and its elongation ∆l is expressed by the following formula: where , are the i-th strain and stress value respectively defining the steel pipeline material constitutive relationship, A is the cross section area of the pipe, Fi=A• is axial force in the pipe corresponding to an axial stress equal to , Ei=( - -1)/( - -1) is the slope of the i-th seg- ment defining the pipe multi-linear stress-strain relationship and i is the pipeline elongation corresponding to the axial force Fi. In particular, E1 and 1 are respectively the elastic stiffness of the steel pipeline and its yield stress. Instead, fs is the maximum soil friction force per unit length of the pipe- line, u0 the relative displacement between the soil and the pipeline when sliding occurs, k=fs/u0 is the rigidity of friction interaction at the soil pipeline interface and F0 is the force in the buried pipeline when sliding occurs at the soil-pipe interface, as schematically illustrated in the figure 5. Moreover, it is observed that in the case where the pipeline ends con- nected to the equivalent-boundary spring remain in the elastic range (i=1, F<F1), the expression (1) is similar to the approximated formula pro- posed by liu et al. [5]. In the figure 6 is illustrated the relationship between the elongation ∆l and the axial force F for the equivalent-axial spring corresponding to the clay soil conditions and pipeline characteristics considered in the present study, calculated using the expression (1). Figure 3. Schematic representation of the procedure for determining the soil reaction to the pipeline movement in the axial direction. Figure 4. Schematic representation of the axial constitutive behaviour of the: a) Steel Pipeline; b) Pipe-Soil Interaction Figure 5. Schematic representation of the axial forces and elongations acting in the pipeline segment away from the fault. 0 PiPeLine TeCHnoLoGy JoURnAL 35 RESEARCH / DEVELOPMENT / TECHNOLOGY AnALySiS ReSULTS Similarly to the procedure followed within recent european Research Projects [6, 7] three principal modes of structural failure are consid- ered for evaluating the pipeline seismic performance: 1. tensile strain limit of 3%, as indicated in the eurocode 8 - Part 4 [8] which can lead to consequent rupture of the pipe wall due to loss of strength capacity in the pipe material. 2. local buckling of the pipeline caused by an abrupt increase of compressive strains at the compressive side of the pipe cross section. 3. excessive ovalization of the pipeline cross section. Following the indications contained in Gresnigt, 1986 [9], the critical oval- ization parameter, intended as the ratio of the minimum pipe diameter to its initial diameter, is assumed equal to 15%. the variation of the plastic axial strain at the most stressed genera- tor of the pipe wall, in the case of pipeline oriented perpendicularly to the fault trace (ß=0o), for different values of fault displacement ∆f is indicated in the figure 7. It can be observed that the onset of lo- cal buckling occurs for a fault displacement equal to 41 cm, at a dis- tance of about 4.3 m away from the fault trace, where the maximum compressive plastic strain in the pipeline reaches 0.45%. Beyond this plastic deformation region, the pipeline remains essentially elastic. In the figure 8 are illustrated the displacement contours for the pipe- line and the fixed part of the soil close to the fault trace where the onset of local buckling occurs, whereas in the figure 9 is illustrated the evolution of the deformed shape of the pipeline and axial strain contour at the region of local buckling for different values of the fault displacement ∆f. In the case of the fault trace forming a negative angle ß=-10° with the normal to the pipeline axis, the onset of local buckling is observed earlier, for a fault displacement value equal to 23 cm, at a distance of about 3.75 m away from the fault, as illustrated in the figure 10. Instead for positive values of the angle ß formed by the fault trace with the normal to the pipeline axis, the predominant limit state is the elevated section deformation. It is observed that the 15% performance limit of section ovalization is reached in the pipeline for values of the fault displacement varying from 85 cm to 1.09 cm, in function of the inclination angle ß. As schematically illustrated in the figure 11, the excessive section ovalization region in the pipeline is localized close to the fault trace which is also the area where maximum pipe axial forces occur. ConCLUSionS. In order to evaluate the seismic performance of a buried pipeline sub- jected to strike-slip faulting, a detailed numerical procedure has been adopted that considers the pipe-soil system as a three dimensional continuum model, accounting for contact and friction interaction at the soil-pipe interface. Being the continuum modelling computationally expensive, the re- gion of the pipe soil system away from the fault is modelled as a single equivalent axial spring connected to the pipe shell elements through appropriate constraints. the force displacement relationship of the equivalent axial spring is obtained analytically taking into ac- count the axial constitutive behaviour of the pipeline as well as the axial soil-pipeline interaction. the obtained axial spring constitutive behavior is subsequently implemented in ABAQUS finite element software [4] for the numerical analysis purposes. this modeling pro- cedure permits to largely reduce the needed memory and compu- tation time of the calculator, compared to the one where the entire length of the pipeline is modelled with nonlinear shell elements, and the surrounding soil with solid elements. Figure 6. Relationship between F and ∆L for the equivalent-boundary springs corresponding to the soil condition considered, calculated using the formula (1). 36 PiPeLine TeCHnoLoGy JoURnAL RESEARCH / DEVELOPMENT / TECHNOLOGY Figure 7. variation of the plastic axial strain at the most stressed generator of the pipeline wall for different values of fault displacement, in case of ß=0° Figure 8. Displacement contours for the fixed soil part (ß=0°) close to the fault trace where the onset of local buckling occurs. Figure 9. evolution of the plastic axial strain contour and deformed shape of pipeline at the region of local buckling for different values of the fault displacement ∆f, in the case of ß=0°. PiPeLine TeCHnoLoGy JoURnAL 37 RESEARCH / DEVELOPMENT / TECHNOLOGY Author Gersena Banushi Phd Student technische Universität Braunschweig, Germany & Università di Firence, Italy g.banushi@ing.unipi.it References [1] S.t. Barbas and M.S. weir, Strain-based design methodology for seismic and arctic regions, ISOPe-2007-SBD, pp. 3073▁3080, 2007. [2] M. O’Rourke and X. Liu, Response of buried pipelines subject to earthquake effects”, Multidisciplinary Center for Earthquake Engineering Research, SUNY-Buffalo, New York, 1999. [3] c-cORe, honegger D.G, and SSD, Inc, 2009, “Guidelines for constructing natural gas and liquid hydrocarbon pipelines through areas prone to landslide and subsidence hazards, Final Report prepared for Design, Materials, and construction committee of Pipeline Research council International, Inc. [4] aBaQUS analysis User’s Guide, Simulia, Providence, RI, USa, 2014. [5] liu a., hu Y., Zhao F., li X., takada S., Zhao l., 2004, an equivalent-boundary method for the shell analysis of buried pipelines under fault movement, Acta Seismologica Sinica,Vol. 17, pp. 150–156. [6] Karamanos, S., Demofonti, G., tsatsis, a.,lucci, a., Dijkstra, G., Gazetas, G., Sarvanis, G.,anastasopoulos, I., Ferino, J., es, S.v., Gresnigt, N.,Dakoulas, P.,vazouras, P., huinen, w., 2013, Safety of Buried Steel Pipelines Under Ground-Induced Deformations (GIPIPe), annual Report RFSR-ct-2011-00027 Project. [7] Fernandes a. a., De Jesus a., Jorge R. N., coppola t., van wittenberghe J., Martinez X., Oller S., Karamanos S. a., Schaf- frath S., eichler B., Novokshanov D., Banushi G., Morelli F., Salvatore w., Nonn a., erdelen-Peppler M., Pires F., Seabra M., thibaux P., 2014, Ultra low cycle fatigue of steel under high-strain loading conditions, annual Report RFSR-ct-2011-00029 Project. [8] eurocode 8, 2006, Design of structures for earthquake resistance - Part 4: Silos, tanks and pipelines, eN 1998-4. [9] Gresnigt, a.M., 1986, Plastic Design of Buried Pipelines in Settlement areas, heRON, vol. 31, No. 4. Figure 10. Deformed shaped and localization of local buckling for the case of fault trace inclined at an angle ß= -10° with respect to the pipeline normal, and a fault displacement value ∆f=23cm. Figure 11. Deformed shape with indicated the localization of excessive section localisation close to the fault trace, in the case of ß = 40° 38 PiPeLine TeCHnoLoGy JoURnAL Tecno Plug™ | High Pressure Pipeline Isolation Double Block & Bleed Isolation Leak-Tight Seals Zero-Energy Zone The Tecno Plug™ provides fail-safe Double Block and Bleed pipeline isolation for high pressure applications while the system remains live and at operating pressure. Dual seals provide a zero-energy zone to enable maintenance work to be carried out safely and efficiently while meeting industry-led Double Block and Bleed requirement. Self-Energisation Taper Lock Grips Valve Maintenance STATS GROUP www.statsgroup.com Managing Pressure, Minimising Risk Pipeline Tech Journal Ad 2015.indd 2 16/02/2015 12:41:33 Play video RESEARCH / DEVELOPMENT / TECHNOLOGY Grand theft PiPeLine Finite element simulation of guided waves to detect product theft from pipelines > by: Salisu El-hussein, University of Aberdeen, Uk / Dr. John harrigan, Amec Foster wheeler, Uk / Dr. Andrew Starkey, University of Aberdeen, Uk PTC-PoSTeRSHoW This paper will be presented during the “Scientific Advances Poster Session” at 10th Pipeline Technology Conference 40 PiPeLine TeCHnoLoGy JoURnAL RESEARCH / DEVELOPMENT / TECHNOLOGY Product theft (hot tap) and intentional attack (vandalism) are among the major causes of reported pipeline failures. the existing pipeline inspec- tion techniques are mainly reactive measures to detect damage/defect. Guided waves (Gws) have potential for the real time structural health monitoring (SHM) of pipelines and other structures. GW offers the ad- vantages of long range examination of a structure and rapid detection of damage. as an example stress waves generated through physical at- tack on a pipeline propagate in the form of Gws. these signals can be detected to provide information about the source and location of the interference. Deliberately excited Gws can be used to detect the pres- ence of additional features such as small branch introduced to initiate a product theft. Finite element (Fe) analysis is conducted on a 12 in (305 mm) diameter steel pipe with 12 mm wall thickness to investigate the potential of longitudinal l(0,1) and torsional t(0,1) Gw modes for long distance propagation. the results show that a low frequency tone burst excitation modified by a Hanning window produces a GW with low at- tenuation and dispersion. For example, at 2.5 khz centre frequency, the attenuation coefficient is 0.00034 m-1. At this attenuation, the signal would theoretically retain more than 10 % of its original energy after a propagation distance of 8 km. the sensitivity of Gw at this frequency was tested with detection of 2 in (50 mm) branch pipe attached along the 12 in pipeline. inTRodUCTion And BACkGRoUnd third party activities constitute about 60 per cent of the reported pipeline failures [1]. Intentional pipeline damage and oil theft are also sources of concern even in developed countries like United States [2], United Kingdom [3] and more especially developing countries like Nigeria [4]. In Nigeria for example, a total of 15,796 cases of pipeline vandalism was recorded between 2000 and 2010. these resulted in estimated 2,800 fatalities, $1.2bn cost of repairs and daily revenue loss to the government of $10.4 million [5]. the damages to the environ- ment and ecosystem are unquantifiable in monetary value. There are many pipeline inspection and monitoring techniques in the litera- ture. however, in the area of third party related damages, cost-ef- fective pipeline monitoring is still required. at selected frequen- cies, Gws have the potential to meet this requirement. the stress waves generated during physical attack on a pipeline can provide a signal that is transmitted along the pipeline. Fig. 1 illustrates the stress waves generated either deliberately by a transducer or ac- cidentally as a result of an attack on a pipeline. For an attack on the line, the signal generated can be detected to serve as an early warning for the occurrence of vandalism/theft. alternatively, a Gw can be generated deliberately for inspection of the line. The difficulties associated with interpreting signals recorded at a remote location are associated with: energy dissipation; dispersion; and formation of multiple Gw modes. “IN ThE ArEA oF ThIrD PArTy rElATED DAMAGES, CoST- EFFECTIvE PIPElINE MoNITor- ING IS STIll rEqUIrED” > Salisu El-Hussein, Dr. John Harrigan; Dr. Andrew Starkey Figure 1 Illustration of guided waves generated by (i) an active transducer; (ii) external interference abstract PiPeLine TeCHnoLoGy JoURnAL 41 RESEARCH / DEVELOPMENT / TECHNOLOGY eXiSTinG PiPeLine inSPeCTion And MoniToRinG TeCHniqUeS there are many pipeline inspection and moni- toring techniques in the literature. they range from visual inspection, wireless sensor networks (WSN) to fibre optic, acoustic, electromagnetic, ultrasonic methods and magnetic flux leakage (MFl). the last two are the most common pipeline inspection and monitoring techniques [6]. Most of these techniques are reactive in nature or re- quire point-to-point transducer movement. In ad- dition, WSN and fibre optic methods are difficult to retrofit. Table 1 summarises the advantages and disadvantages of common pipeline monitoring techniques. BASiC GUided WAve THeoRy Gw forms as a result of superposition of longitudi- nal and shear waves reflecting between structural boundaries. the possible constructive interferenc- es which result from these reflections represent the number of Gw modes which will propagate along the length of the waveguide. Unlike longitudinal and shear bulk waves, their velocity is not only dependent on the material properties but also on the thickness of the material and the wave frequency. Gws experience energy leakage when in contact with a surrounding medium (e.g. soil) or internal fluid. Cylindrical waveguides (e.g. pipes) support 3 modes of GW vibrations: longitudinal, torsional and flex- ural. according to the convention by Silk and Bainton [7] they are labelled as l(0,m), t(0,m) and F(n,m) for longitudinal, torsional and flexural modes respectively. The letter ‘n’ represents the harmonic order of the circumferential variation within the wall thickness while ‘m’ describes the sequential number of modes of the same family. For example, L(0,1) is the first longitudinal wave mode to exist with zero cycles of particles’ displacement variation around the circumfer- ence. Gws in cylindrical structures are governed by Navier’s equation, which in vector form can be seen below [8]: where u represents displacement, λ and µ are lamés constants, is the 3-dimensional differential operator and p is the material density. For detailed derivation of Gw equa- tions, the reader is referred to reference [8]. GUided WAve STRUCTURAL HeALTH MoniToRinG ShM is a technique employed for the maintenance of large struc- tures such as rail-track and pipeline networks. ShM seeks to replace scheduled maintenance with condition based maintenance. In pas- sive mode, ShM consists of measuring the operational parameters of a structure and indirectly assessing its state. acoustic emission and thermal sensors are commonly used in passive ShM. active ShM assessed the structure directly in order to detect the presence of defects. Permanent sensors and relevant monitoring techniques are used to provide information on the state of the structure. Resonant frequency measurements, wSN and Gw sensors are commonly used for active ShM. t(0,1) and l(0,1) are the common Gw modes used in NDt for defect detection. the t(0,1) mode has the advantage of being more sensitive to longitudinal defects while l(0,1) has more poten- tial for long distance propagation. In most ShM techniques, there is a trade-off between resolution and spatial coverage. GWs combine long distance propagation with a good resolution for defect location and identification [9]. Due to these advantages, many studies have been carried out on the inspection of pipes and other structures us- ing Gws. Methods Advantages disadvantages visual Inspection - Effective in a relativley small area - labour intensive - accessability limitation electromagnetic method - Cost-effective in surface and near surface defects - Requires probe movement acoustic emission method - can operate in passive and active modes - high cost of sensors - Requires densely spaced sensors Fibre optic method - Sensitivity along the entire length - Dual function of communication and monitoring - Susceptible to damage during installation - high installation cost wireless sensor network - little inteference with structure operation - large multi-hop network required Ultrasonic methods - Good sensitivity to the presence of defects - Requires probe movement Guides waves - In-Service Monitoring - long distance coverage - Cost effectiveness - Multiple modes formation - complicated signal processing table 1 comparison of common pipeline inspection and monitoring techniques ()()()uut u ×∇×∇+∇∇+=µµλδ δρ .2.2 2 ∆zyxδδδδδδ///++ P 25m 25m 25m 25m N1 N2 N3 Pipe 0.305m Figure 2: Configuration of model pipe showing nodal locations 42 PiPeLine TeCHnoLoGy JoURnAL RESEARCH / DEVELOPMENT / TECHNOLOGY FiniTe eLeMenT SiMULATion oF GUided WAveS the mathematical solution of Gw has been obtained for simple geometries such as a circular cylinder [9]. For com- plicated geometries no mathematical solution is available. Numerical modelling such as boundary element and Fe are used for the analysis of complicated geometries. Fe analysis has been successfully employed as a tool for Gw propagation analysis in plates and pipes [10]. the use of Fe modelling can provide the required understanding of stress waves propagating along a pipeline for application against product theft and vandalism. Fe ModeL the model was generated with aBaQUS/explicit version 6.12. the simulation was conducted on a 12 in (305 mm) outer diameter, 12 mm wall thickness and 100 m long pipe. Fig. 2 shows the configuration of the model pipe and three nodal loca- tions (N1, N2 and N3) defined along the pipe. The pipe material was made from mild steel with a Young modulus E = 209 GPa, Poisson’s ratio v = 0.3 and density p = 7850 kgm-3. a 3-dimensional linear brick, 8 node solid elements with reduced integration (c3D8R) was chosen for this analysis. a sweep meshing technique was adopted with a 24 mm mesh size in the longitudinal direction. aBaQUS automatic time step (∆t) which stabilised at 0.676 µs was adopted and was sufficient to avoid numerical instability. the element length chosen met the requirement of 20 nodes per smallest wavelength in the model. the excitation signal was a 5-cycle tone burst modified by a Hanning window with a centre frequency of 2.5 khz. LonGiTUdinAL eXCiTATion l(0,1) mode was excited by applying a uniform pressure pulse load at one end of the pipe as shown in Fig. 3. Stresses and displacements were monitored at the three nodal locations shown in Fig. 2. time domain displacement signals recorded at these locations and their correspond- ing frequency spectra are shown in Fig. 4. From Fig. 4 (a) there is no appreciable change in signal shape as the wave propagates from N1 to N3 (low dispersion). Fig. 4 (b) also shows little decrease in magnitude of the frequency content (low attenuation). Using the signals at N1 and N2, the attenuation coefficient of the L(0,1) mode at this centre frequen- cy was calculated as 0.00034 m-1. From this attenuation, the signal can theoretically propagate 8 km and retain more than 10 per cent of its original energy. ToRSionAL eXCiTATion t(0,1) modes were generated by assigning a displacement rotation to the edge nodes. the edge nodes were coupled to a master node as shown in Fig. 5. all other parameters remain the same as for the lon- gitudinal wave simulations. Fig. 6 shows the rotational displacements at the three nodal locations and their corresponding frequency spec- tra. compared to the l(0,1) modes, the change in shape as the signal propagates from N1 to N3 is more noticeable (higher dispersion) and the decrease in magnitude of the frequency spectrum is higher (higher attenuation) as shown in Fig. 6 (a, b). at a centre frequency of 2.5 khz, the attenuation coefficient of the T(0,1) mode was calculated as 0.0083 m-1. From this attenuation, the potential propagation distance at this frequency is less than 1.5 km. this shows that the l(0,1) mode has more potential for long distance propagation than t(0,1) mode. Figure 3 longitudinal guided wave excitation Figure 4 longitudinal displacement signals recorded at 3 nodal positions: (a) time domain and (b) frequency spectrum Figure 5 torsional guided wave excitation PiPeLine TeCHnoLoGy JoURnAL 43 RESEARCH / DEVELOPMENT / TECHNOLOGY Figure 6 torsional displacement signals recorded at 3 nodal positions: (a) time domain and (b) frequency spectrum inTeRACTion oF LoW FReqUenCy GUided WAve WiTH A BRAnCH PiPe Oil theft is often carried out by attaching a branch pipe to siphon pe- troleum products. the model pipe was simulated with a 2 in. branch pipe attached at the N2 location and the stresses and displacements were recorded at N1 and N3. Fig. 7 shows a snapshot of the stresses as the wave propagates along the pipe and up the branch. Fig. 8 (a) shows the displacement history at node N1. The first pulse recorded is the incident signal, I, that travels from left to right in Fig. 2. Some- time later there is a similar pulse but of much lower amplitude. this is the reflection from the branch, termed RB in Fig. 8. The last pulse, termed Re, is similar in magnitude to the incident wave. this is the part of the wave that was transmitted across the branch and reached the far end of the pipeline before being reflected back towards node N1. Fig. 8 (b-d) shows the frequency spectra for the pulses termed I, RB and RE. The reflection from the branch was quantified in terms of reflection coefficient (RB/I) in the frequency domain. Comparing Figs. 8 (b) and (c), there is similarity between the frequency spectra of the incident and branch reflected pulses. This allows the reflected signal to be detected by cross-correlation with the incident signal. a time- shift of approximately 5 ms was observed from the cross-correlated signal. From this time-shift and phase velocity of the wave at 2.5 khz the distance of the branch from the sensor location (N1) was calcu- lated as 25.5 m. this shows the potential of Gw at this frequency to detect and locate a small branch attachment to a pipeline. Figure 7 Snapshot of the stress contours along the model with a branch attachment 44 PiPeLine TeCHnoLoGy JoURnAL RESEARCH / DEVELOPMENT / TECHNOLOGY Figure 8 (a) Strain history at N1 showing Incident, branch reflection and end reflection pulses and (b-d) their corresponding frequency spectra ConCLUSionS the results show that the longitudinal Gw mode can propagate long distances without appreciable change in shape. In contrast, the torsion- al mode shows higher dispersion within the same propagation distance. It is shown that at low frequency (2.5 khz) the l(0,1) mode can be used to detect a 2 inch branch in a 12 inch pipeline. The reflection coefficient for the case considered is approximately 4 % of the incident signal and the reflection will decay with distance. However, the reflected signal from the branch was observed to have the same frequency content as the incident signal. As the reflected signal therefore has a known fre- quency, it is more easily detected by e.g. cross-correlation. The reflected signal can be used to detect the presence and the location of a small branch on a pipeline. ACknoWLedGeMenT the authors wish to acknowledge the support of Petroleum technology Development Fund-Nigeria for funding this research work. [1] Jin Y and eydgahi a 2008 Monitoring of Distributed Pipeline Systems by wireless Sensors Networks Proc. IaJc-IJMe Int. conf. ISBN 978-1-60643-3-79-9. [2] Parfomak P w 2004 Pipeline security: an overview of federal activities and current policy issues cRS report for Congress, Congress Research Service, the library of Congress – available online at www.fas.org/ sgp/crs/Rl31990.pdf [3] Daveis P M, Dubois J, Gambardella F, Uhlig F, larié J and Fredriksson M 2009 Performance of european cross-country oil pipelines-Statistical summary of reported spillages in 2007 and since 1971 Brussels:cON- cawe [4] anifowose B, lawler D M, horst D and chapman l 2012 attacks on oil transport pipelines in Nigeria: aquatative exploration and possible explanation of the observed patterns applied Geography 32 636-651 [5] Udofia O O and Joel O F 2012 Pipeline vandalism in Nigeria: Recommended best of practice of checking the menace SPe annual Int. conf. and exhibition 6-8 august 2012 abuja-Nigeria [6] Diez M D, Majado SS, cassiba I e and Sans P S 2011 State of the art integrity inspection and monitoring in deep water assets, 10th offshore Mediterranean Conf. and exhibition, 23 -25 March 2011 Ravenna, Italy. [7] Silk M G and Bainton K F 1979 the propagation in metal tubing of ultrasonic wave modes equivalent to Lamb waves Ultrasonics 17 11 – 19 [8] Graff K F 1975 Wave motion in elastic solids (Oxford: Clarendon Press) [9] Gazis D c 1959 three dimensional investigation of the propagation of waves in hollow circular cylinders I analytical foundation J. acoust. Soc. am. 31 568-578 [10] Lowe M J S 1998 Characteristics of the reflection of lamb wave from defects in plates and pipes In D O thompson and D e chimenti editors Review Progress in Quantitative NDe pg 113-120 Plenum Press New York References Authors Salisu el-Hussein University of aberdeen School of engineering aberdeen, UK r02se13@abdn.ac.uk +44 (0) 1224 272801 dr John Harrigan amec Foster wheeler aberdeen, UK john.harrigan@amecfw.com +44(0)1224 294198 dr Andrew Starkey University of aberdeen School of engineering aberdeen, UK a.starkey@abdn.ac.uk +44 (0) 1224 272801 PiPeLine TeCHnoLoGy JoURnAL 45 CSSP As the second largest oil producer of oPeC nations, iraq’s economy fully depends on the stability and growth of the national oil industry. it is therefore of paramount importance to keep the oil production at target level. To achieve this goal it is necessary to apply secondary oil recovery methods. The method selected for the oil fields in Southern Iraq is to inject water into the reservoir in order to maintain the reservoir pressure and to in- crease the percentage of oil extraction enabling one of the world’s top oil producing regions > by: Tobias Walk , ILF Consulting Engineers > Representative IlF Design, Major water Pipeline, Middle east cOMMON SeawateR SUPPlY PROJect RESEARCH / DEVELOPMENT / TECHNOLOGY Water Source for oil Field Pressure Maintenance The amount of water required in Southern Iraqi oil fields for this purpose is in the range of 12.5 million barrels of water per day, which is equal to 24 m3/second. > Iraq Area Map showing CSSP location within Basrah province > CSSP Pipeline Routing Overlay onto the Iraq Satellite Image cOMMON SeawateR SUPPlY PROJect Such quantities of water are not available in the project provinces of al-Basrah and Missan, where temperatures regularly ex- ceed 40 degrees celsius and where the annual precipitation rate is less than 155 mm. Sourcing water from the famous eu- phrates and tigris rivers would only amount to 10% of the quantities required in the oil fields. Furthermore, use of these local wa- ter sources would significantly detract from the life sustaining water for the local popu- lation and community needs. The only source available in sufficient quan- tity for the needs of the Project is seawater. In consequence it is logical to take this sea- water from a single point, treat it and sup- ply it via a common system to the various oil fields. The evolving Project is called the common Seawater Supply Project cSSP. oRGAniSATionAL SeT UP oF THe oWneR the South Oil company (SOc) received a mandate from the Iraq Ministry of Oil and International Oil companies (IOcs) to de- velop and operate the cSSP. SOc’s key stakeholders in development of the project include major global opera- tors in the oil and gas industry such as BP, cNOOc, eNI, exxonMobil, lukoil, Petrochi- na, Petronas, and Shell. In order to support SOc, the consultant ch2M hill has been contracted as PMc (Project Management consultant) to man- age and coordinate the execution of this project. iLF’s CHALLenGinG TASk ILF identified this project as early as 2010 and presented preliminary technical con- cepts to exxonMobil, who developed this project in the initial phase. Subsequently, as SOc took over the mandate for imple- mentation of the project from exxonMobil, IlF kept a strong focus on the develop- ments. In 2013, ILF was pre-qualified as the only engineering company for both FeeD packages (Front end engineering Design) - i.e. for the StF (Seawater treating Facilities) and the pipelines. Both proposals were sub- mitted in January 2014. During the follow- ing five months, technical and commercial details were negotiated and at the end of June 2014, IlF received a letter of award to perform the FeeD package for the cSSP pipelines. the contract between SOc and IlF was signed in abu Dhabi on 20 august 2014. IlF has since developed an execution plan to deliver the tender Documents within one year, which is extremely challenging. It will require taking full advantage of IlF’s broad know-how and experience in designing and managing the construction of large water transmission pipelines in the Middle east. to provide the best value for SOc, IlF is leveraging the expertise of multiple offices. the project management team resides in abu Dhabi, engineering is executed from the IlF center of excellence in Munich and the Basrah office handles all local project requirements. FeeD execution is split into two distinct phases: Optimization and Design Develop- ment, each within a 6 month schedule. the project is currently in the optimization phase, which is a specialty of IlF. as a result of these studies a diameter of 56” has been selected for the multiple pipelines running from the Seawater treatment Facility to the various delivery stations in the oilfields. The route verification is nearly complete and has identified six major water course crossings including the euphrates, the ti- gris and the Shatt al-arab. System design is well on its way including the simulation of transient flow conditions (another specialty of IlF) and the design of the pressure control and surge protection facilities at the delivery stations. PiPeLine TeCHnoLoGy JoURnAL 47 RESEARCH / DEVELOPMENT / TECHNOLOGY PRoJeCT SUMMARy the common Seawater Supply Project (cSSP) will supply seawater to the oil fields Zubair, Tuba, Rumai- la, west Qurna, Majnoon, Gharraf, halfaya and Mis- san in the south of Iraq. the intake and the Seawater treatment Facility (StF) will be approximately 40 km south of Basrah at the west bank of the Khor al Zubair river. Phase one of the project shall have a capacity of 7.5 million barrels of water per day allocated to the vari- ous oil fields in South Iraq. After completion, the full built out design capacity of the cSSP amounts to 12.5 million barrels of water per day which is equal to 24 m3/sec. From the Shipping Pump Station (SPS), the water will be pumped via two pipeline corridors through multi- ple 56” steel pipelines to the oil fields over distances of up to 270 km. the discharge pressure of the shipping pump station will be in the range of 45 bar. At the delivery stations the water will flow into the tanks of the oilfield facilities, thereby providing hy- draulic separation between these facilities and the cSSP. the estimated cost of the project is in the order of magnitude of 12 billion U$ and it is envisioned that this megaproject will require 3 years for completion. with an ultimate capacity of 12.5 million barrels of water per day, the cSSP will be one of the biggest plants of its kind in the world. > Representative IlF Design, Major water Pipeline, Middle east Author Tobias Walk Director of Projects - Pipeline Systems IlF consulting engineers Munich, Germany tobias.walk@ilf.com +49 / 89 / 25 55 94 - 244 48 PiPeLine TeCHnoLoGy JoURnAL RESEARCH / DEVELOPMENT / TECHNOLOGY dent HUnTinG For pipeline integrity management detailed feature assessments based on finite element analysis (FEA) are getting more and more important. Consid- ering dents as one of the major integrity threads of pipelines, the finite ele- ment analysis helps to differentiate between severe and benign dents. using high resolution in-line inspection technologies and finite element analysis Usually, the severity of dents is assessed by using standards and methods, which refer to depth, length and width as main criteria. In many cases, these methods turn out to be over-conservative and lead unnecessary pipe repairs or replacements, resulting in unnecessary costs for pipeline operators. A more accurate differentiation between severe and un-severe dents can be provided on basis of strain and stress values. this type of information can be derived from high resolution geometry data, which captures a high accurate contour of the pipeline. this type of assessment is not only limited to plain dent conditions any longer. while high resolution geome- try tools reliably identify dents associated with girth weld or long seams, dents associated with metal loss corrosion, mechanical damage or crack can be iden- tified by additional ILI technologies, namely MFL, Dual Field MFl, Ut and eMat. an adequate catego- rization of dent conditions is key for the selection of the right measure. For plain dent conditions the ROSeN Group devel- oped an automated streamlined process, which al- lows to rapidly generate and provide stress concen- tration factors, using the established aBaQUS code. Based on this information, the remaining life can be concluded by taking additional information, coming from the ScaDa System into account. For dents, associated with metal loss or welds, an extended engineering assessment based on Fea allows an adequate assessment of these types of dents. the article introduces IlI technologies and methods. It presents the results from large scale testing and case stud- ies to underline the usage of finite ele- ment analysis as instrument to assess the pipeline integrity. the accuracy of the stress concentration factor, derived from high resolution geometry data, is validated in multiple test comparing the measurements with laser scans, taken with established optical devices. “A SET oF DENT ANAlySES ThAT MAy hAvE PrEvIoUSly TAkEN wEEkS CAN Now BE rEDUCED To A FEw hoUrS” > Thomas Walther, Rosen Group > by: Thomas walther, roSEN Group abstract figure 1: 24-inch test sample prior to denting 50 PiPeLine TeCHnoLoGy JoURnAL RESEARCH / DEVELOPMENT / TECHNOLOGY THe HUnTeR RoGeo XT 42” iLi Tool inTRodUCTion ID anomalies, especially dents, are a significant threat for pipeline integrity. They often fail due to fatigue, caused by varying pressure cycles within a pipeline over lifetime. But commonly dent severity is not assessed considering dynamic loads. historically, regulations regarding the severity of dents have been governed by one of two metrics: dent depth or strain. however, the technology and the inspection devices improved over the years, but still dents are assessed using the depth or the strain criteria. the dent depth crite- ria permits dents with a depth up to 6% of the nominal diameter in both, gas and liquid pipelines, although many operators already use stricter limits and targeting those above a depth of 2% for evaluation. Using the strain-approach plain dents of any depth are considered acceptable, if the strain does not exceed 6%. the method becomes more common, as strain calculations have become readily available. therefore, the strain in the hoop and axial planes of the dent is calculated based on the radii of curvature in each plane and the extensional strain based on the length of the dent. an approach is outlined in appendix R of aSMe B31.8. Both, the strain-based and dent depth approaches have similar shortcomings. First, neither approach is adequate for complex dents or in cases, where interacting dents may be present. In the case of depth, the shape of a dent is completely neglected. a long, deep dent is not distinguished from a shorter, steeper dent. while strain-based approaches im- prove on this shortcoming and can be useful for well-behaved dents, applying the methodology where varying curvatures may exist in a complex dent becomes significantly more difficult. To overcome these shortcomings Finite Element Anal- ysis (Fea) can be used to analyze dents in a more adequate way. complex dents and well-behaved dents are both suitable for Fea, and the results are not sensi- tive to small undulations in data. the severity is calculated directly based on the response of the dent to the applied loading, regardless of shape or size. In order to use Fea for detailed assessment of dents, a highly accurate recorded counter of those is required. Confirmed effectiveness the case study and additional investigations on more than 113 dents demonstrated that Fe-Dat in combination with the RoGeo Xt data provides reliable and repeatable stress concentration factors to assess the severity of dents. Unique sensor array the RoGeo Xt has an unique combination of caliper and eddy current sensors, called the mechatronic measurement system, which can precisely measure the profile and contour of geometric features. figure 1: 24-inch test sample prior to denting PiPeLine TeCHnoLoGy JoURnAL 51 RESEARCH / DEVELOPMENT / TECHNOLOGY “ThE SCF IS ProPorTIoNAl To ThE SEvErITy oF ThE DENT AND CAN BE USED To CAlCUlATE ThE rEMAINING lIFE oF AN ANoMAly” > Thomas Walther, Rosen Group HiGH ReSoLUTion GeoMeTRy inSPeCTion deviCe (RoGeo XT) In order to enable Fea of dents, an in-line inspection system needs to capture the shape of the dent with the utmost precision. traditional caliper devices do not provide the required resolution to use the re- corded data for Fea. common caliper devices do not have full surface coverage. the majority of them is equipped with one senor plane, not covering the whole circumference of the pipeline. the resulting low- er resolution compared to two sensor plane devices and the exist- ing coverage gabs result into misinterpretations and less accurate measurements of the dent shape. But not only the amount of sen- sor planes guarantees a high accurate measurement of the counter. Even two sensor plane devices will be influenced under certain run conditions. especially during high inspection velocities, caliper devic- es, independent of the coverage, will have an increased movement while passing ID reductions. this causes a loss of continuous contact with the internal surface, leading to inaccuracies and misrepresenta- tions of the dent shape. But also at low speed abrupt changes along the pipe wall, like diameter changes may not be captured correctly. the RoGeo Xt has an unique combination of caliper and eddy current sensors, called the mechatronic measurement system, which can precisely measure the profile and contour of geometric features. With both information, coming from the eddy current and the caliper sen- sor, even movement on ID reduction and abrupt changes at the inter- nal pipe surface can be compensated and will be precisely measured, even in the presence of wax or debris. the device is equipped with two sensor planes, resulting in an 100% circumferential coverage of the inner surface of the pipeline. This device fulfills the perquisite de- scribed above for highly accurate measurements to be used for Fea. The RoGeo XT tool fleet today covers pipeline sizes ranging from 6” to 48”. Figure 1 shows a 42inch inspection device. FiniTe eLeMenT AnALySiS, STReSS ConCenTRATion FACToRS And ReMAininG LiFe AnALySiS to characterize the severity of discontinuities in uniform load bearing objects, the stress concentration factor (ScF) is often taken into ac- count. the ScF describes the ratio of the peak stress in a body to the calculated nominal stress. the local stresses within an object depend on the cross-sectional area of it. If the area contains a discontinui- ty, such as a hole, the local stresses around the discontinuity may be several times higher than the nominal stress. this relationship is characterized by the ScF. For simple shapes, such as holes, analyt- ical ScFs are widely available. however, for more complex shapes the SCF is derived from finite element models. This approach is used in offshore structural analysis, where SCFs are combined with pub- lished S-N curves when determining fatigue lives for structural con- nections. In this case the ScFs is used to calculate the peak stresses, which is required for fatigue calculations. It is straightforward to expand the ScF methodology to the assess- ment of dents in pipelines. the nominal stress state in a pipeline is easily classified as a function of the internal pressure according to Barlow’s equation. the ScF can be derived from a precise model of the dent within a finite element program. The model can be directly constructed from the RoGeo Xt data. Once the model is built, the ScF is calculated by the finite element program, considering an applied internal pressure and the maximum principle stresses. Historically, finite element analyses have been cost intensive and time-consuming for operators, but advances in technology have re- moved both of these limitations. Improved inline inspection technol- ogy (ILI) as well as improved data processing power enable the effec- tive usage of Fea for dents in pipelines and permitted the creation of a streamlined process, referred to as the Finite element Dent analy- sis tool (Fe-Dat). the Fe-Dat is not limited to single dents only. It is developed to analyze a large number of dents precisely and ac- curate. It works by taking data directly from a high-resolution IlI tool, building a finite element model, and post-processing the results. A set of dent analyses that may have previously taken weeks can now be reduced to a few hours. the results from the analysis provide the ScF for each dent, which is directly proportional to the severity of each dent and indirectly proportional to the life. In addition, the stress profile in the region surrounding the dent is also provided in the form of stress contours. Using the ScF a fatigue analysis can be done, if the operator pro- vides pressure history data. Based on that a rain-flow analysis can be performed in order to calculate an equivalent number of cycles a par- ticular dent experiences. this equivalent number of pressure cycles can be combined with the calculated ScF to determine the remaining life of a dent. Due to the fact that the relationship between stress and fatigue life is highly nonlinear, a fatigue analyses typically carry large factors of safety. figure 2: Pressure cycled to failure 52 PiPeLine TeCHnoLoGy JoURnAL RESEARCH / DEVELOPMENT / TECHNOLOGY CASe STUdy In order to illustrate the effectiveness of the SCF method and provide a comparison between test data and analytical methods, a case study was performed. therefore, a dent was generated in a 24-inch OD, 0.25-inch wall thickness, Grade X52 pipe sample. Figure 2 shows the test set-up, the indenter and the applied strain gages. the dent was generated by pressing a 2-inch diameter indenter into the pipe to a depth of 3.61-inch- es (15% OD) in an unpressurized configuration. Afterwards, the shape of the dent was recorded by an optical scanner and by the RoGeo Xt in- spection device. Next, the pipe was subjected to target pressure cycles ranging from 100 – 780 psi (9% - 72% SMYS) until failure occurred. The strains were record- ed at intermittent points during cycling. the sample failed after 39,800 cycles when a longitudinally oriented thru-wall crack developed in the shoulder of the dent as shown in Figure 3. the related ScF was calculat- ed out of the recorded stresses from the strain gages and the nominal stress from the recorded pressure range of 690 psi. the ScF from the experimental data was 3.16. In comparison to the experimental data, the analysis was performed us- ing the FE-DAT and the finite element code ABAQUS. An internal pres- sure of 208.3 psi was applied to the model corresponding to a 10,000 psi hoop stress. the analysis completed by the Fe-Dat showed a maximum principal stress of 32,784 psi on the OD of the pipe resulting in an ScF of 3.28. In addition the data from the optical scan was provided and ana- lyzed using aBaQUS in order to maintain consistency with the Fe-Dat. The same internal pressure of 208.3 psi was applied to the finite element model. the calculated maximum principal stress on the OD of the pipe was 38,014 psi yielding a ScF of 3.80. In general, the calculated ScFs and depths compare well, particularly be- tween the Fe-Dat and the test data. the slightly higher ScF shown in the optical scan can be explained by the fact that the optical scan was recorded from the outside, while the RoGeo Xt recorded the inner sur- face. Possible ovailities might not be recorded in the same way as the RoGeo Xt does. however, the Fe-Dat and the test data showed closer agreement for the dent depths and the resulting ScFs. For the sample used for the case study, pressure history data was not available, but as it was ultimately destructively pressure cycled in the lab, comparisons can also be made between the predicted cycles to failure and the actual cycles to failure. Using the calculated ScF of 3.28 and a nominal stress of 33.1 ksi, the predicted number of cycles using the de- sign S-N curve is 3674. The calculated number of cycles is significantly lower than the actual number of cycles (39,800). this was expected, as the usage of a standard S-N design curves provide more conservative results and laboratory testing has usually a higher scatter influencing the remaining life analysis. as previously mentioned, the relationship be- tween stress and remaining live is highly nonlinear, so that even small variations in stress lead to high deviations in the predicted life. ConCLUSion the case study and additional investigations on more than 113 dents demonstrated that Fe-Dat in combination with the RoGeo Xt data pro- vides reliable and repeatable stress concentration factors to assess the severity of dents. In comparison to the strain calculation the ScF cor- relates very well with depth. Furthermore there is also a slight correla- tion between the results using the strain approach and the ScF method. therefore, the B31.8 strain assessment provide valid results for a mo- mentarily situation, but not for a fatigue assessment. the ScF is proportional to the severity of the dent and can be used to calculate the remaining life of an anomaly. the advances in computing and IlI caliper tools have allowed the process of analyzing dents to be streamlined to the point where hundreds of dents can be analyzed quick- ly and the data be made available as part of IlI reports. this approach has been validated through physical testing and represents an advanced metric that can be used to prioritize dents. Author Stay informed!@ Thomas Walther International Service Manager ROSeN technology & Research center Gmbh lingen, Germany twalther@rosen-group.com +49-591-9136-121 Subscribe to our newsletter and be the first to get the latest news and develop- ments on pipeline technologies www.pipeline-journal.net PiPeLine TeCHnoLoGy JoURnAL 53 Nature is our greatest asset. It needs to be preserved and protected as pipeline networks grow and operational efficiency becomes a key requirement. NDT Global provides pipeline inspections with a top first run success rate, superior data quality and rapid inspection report delivery to protect your assets and to preserve nature in all its wilderness and beauty. Protecting your assets, preserving the beauty. www.ndt-global.com Canada | Germany | Malaysia | Mexico | Russia | Singapore | Spain | U.A.E | USA 157_13_NDT_Ad_Forest_420x297mm_korr.indd Alle Seiten 19.03.14 09:26 Nature is our greatest asset. It needs to be preserved and protected as pipeline networks grow and operational efficiency becomes a key requirement. NDT Global provides pipeline inspections with a top first run success rate, superior data quality and rapid inspection report delivery to protect your assets and to preserve nature in all its wilderness and beauty. Protecting your assets, preserving the beauty. www.ndt-global.com Canada | Germany | Malaysia | Mexico | Russia | Singapore | Spain | U.A.E | USA 157_13_NDT_Ad_Forest_420x297mm_korr.indd Alle Seiten 19.03.14 09:26 RESEARCH / DEVELOPMENT / TECHNOLOGY > by: Jan helge Johannessen, Technip-Deepocean PrS Jv THe HABiTAT RWS relies on the habitat, the systems foundation. it creates reference to the pipe and spool and provide a platform for the welding tool remote WeLdinG 56 PiPeLine TeCHnoLoGy JoURnAL RESEARCH / DEVELOPMENT / TECHNOLOGY Statoil have, after several years of testing and technical qualification work, developed a Remote Welding System that was qualified for contingency in the Pipeline Repair System pool services in december 2014. The system is rated for operation down to 1000msw and covers pipelines which are in depths exceeding the limit for diver assisted operations, which is currently 180msw. the new fully remote hyperbaric welding system is mainly for subsea repair of pipelines and covers pipe dimensions from 30” up to 42”. however, the equipment is a huge technical milestone for the subsea business and opens new opportunities in the industry when it comes to planned expansions of infrastructure, bypass of old installations and tie-ins. Different from the diver habitat that operates with pipe ends, butt welding, the remote system involves installation of a pipe spool with pre-welded sleeves, threaded over both pipeline ends, before welding them together by a fillet weld. ConCePT deSCRiPTion – THRee MAin ModULeS the Remote welding System consists of three main modules; a hab- itat, a power & control module (POcO) and the welding tool. In short terms; the habitat is landed over the pipeline, before the pipe and spool are aligned. The habitat is then filled with welding gas (Argon) and dehumidified. The POCO carries the welding tool, and lands onto the habitat. a special designed sealing between the habitat and the POcO provides dry transfer of the welding tool into the habitat. when the welding tool is in position, the pipe and sleeve is preheated before welding operation starts. the habitat main functions are to act as a foundation of the system, creating reference to the pipe and spool and provide a platform for the POcO and the welding tool. It is equipped with 4 individually operated legs, and longitudinal movement for accurately positioning of the hab- itat in reference to the welding position. the habitat functions are also to provide a dry and Argon filled hyperbaric welding environment be- fore the welding tool enters. the operation is remotely operated from a topside control container on the vessel deck. all three modules are equipped with a wide range of cameras, lvDts, pressure, temperature and proximity sensors for feedback and monitoring. the POcO’s main function is to house the welding tool and to provide services for the tool during operations. the POcO enclosure consists of two separate compartments: - electronic compartment containing most of the electronics and pow- er distribution components required for operating the POcO and the welding tool. - tool compartment, containing equipment and systems required to transport the tool in and out of the habitat Both compartments are pressurized with argon whenever submerged and will have a maximum operating differential pressure towards the outside of about 0.5bar. Power communication and gas is supplied through an umbilical from surface. In addition, power sources for welding and preheating is located in 1 bar containers outside the POcO enclosure. when the welding area is dry and acceptable welding conditions are reached inside the habitat, the POcO is launched. after landing on the habitat, the interface (between habitat door and POcO door) is blown down. the doors are opened and the welding tool can engage around the pipe. After doing a path capturing +/-180▁ and inspection of the welding area by cameras, 2 pre-heat bands are engaged around the pipe. the welding can start when pipe and sleeve temperatures are above 50▁C. For support and feedback the welding tool is among others equipped with welding torch tip changer, welding camera, a grinder and various sensors. Remote Welding System (RWS) New fully remote hyperbarbic welding system rated to 1000msw PiPeLine TeCHnoLoGy JoURnAL 57 RESEARCH / DEVELOPMENT / TECHNOLOGY TeCHnoLoGy qUALiFiCATion PRoGRAM (TqP) after going through various system and subsystem testing through- out the project such as Factory acceptance testing, Site Integration test, welding Robustness testing and a Shallow water test, the last part to fulfill the TQP was the Deep Water Test. This test was to vali- date the system and to show that the equipment could produce ac- ceptable welds offshore. The test was twofold with depths on 400msw in Nedstrandsfjorden and 1000msw in Sognefjorden. Two weld sections on a pre-installed pipe spool in the habitat were done on both depths and all the tests were successful. THe WAy FoRWARd The deep water test was the final milestone and completion of the project. Now the Remote welding System is in contingency in the PRS pool, operated by PRS Jv on behalf of Statoil. It is being evaluat- ed to expand its limits with deeper depths, smaller pipes and welding of other pipe materials. PRS Joint venture • Joint venture between technip Norge aS and DeepOcean aSa • contract awarded in December 2014, 5 years with 3 x 2 years option. • Includes operation, maintenance, engineering and development of the Pipeline Repair System at Killingøy in haugesund. Author Jan Helge Johannessen Planning Engineer, PrS Pool services technip-DeepOcean PRS Jv haugesund, Norway jhjohannessen@technip.com +47 67 80 54 48 PoCo ModUL The Power and Control Moduls main function is to house the welding tool and to provide services for the tool during operations. WeLdinG TooL The three moduls of RWS succeeded in all tests and are fully operational. The System can operate in areas down to 1000msw. Play video 58 PiPeLine TeCHnoLoGy JoURnAL QuestIntegrity.com CHALLENGE CONVENTION You’ve got a challenging pipeline with even more challenging validation requirements. Quest Integrity Group’s proprietary, ultrasonic in-line inspection technology and engineering assessment capabilities are structured to help you address the most complex and difficult-to- inspect pipeline challenges. When combined with our suite of integrity management services, Quest Integrity delivers a truly integrated and powerful solution for the onshore and offshore pipeline industry. InVistaTM intelligent in-line inspection capabilities for challenging pipelines: • Provides 100% coverage of geometry and metal loss in a single pass • Inspects dual-diameter and multi-diameter pipelines down to 3” (76mm) • Operates and inspects bi-directionally • Navigates back-to-back 1D bends • Navigates bore restrictions, step changes, reduced port valves • Traverses bottom unbarred tees, wyes and mitre bends • Operates in low flow conditions Get the answers you need to effectively manage your most challenging pipelines. COMPLEX PIPELINE INSPECTIONS. SOLVED. QuestIntegrity.com CHALLENGE CONVENTION You’ve got a challenging pipeline with even more challenging validation requirements. Quest Integrity Group’s proprietary, ultrasonic in-line inspection technology and engineering assessment capabilities are structured to help you address the most complex and difficult-to- inspect pipeline challenges. When combined with our suite of integrity management services, Quest Integrity delivers a truly integrated and powerful solution for the onshore and offshore pipeline industry. InVistaTM intelligent in-line inspection capabilities for challenging pipelines: • Provides 100% coverage of geometry and metal loss in a single pass • Inspects dual-diameter and multi-diameter pipelines down to 3” (76mm) • Operates and inspects bi-directionally • Navigates back-to-back 1D bends • Navigates bore restrictions, step changes, reduced port valves • Traverses bottom unbarred tees, wyes and mitre bends • Operates in low flow conditions Get the answers you need to effectively manage your most challenging pipelines. COMPLEX PIPELINE INSPECTIONS. SOLVED. Play video RESEARCH / DEVELOPMENT / TECHNOLOGY new era oil and gas are an important transport method of the energy sources products worldwide nowa- days and in the near future. However, the major reserves of the oil and gas are mostly located in remote areas. For this reason, pipelines have become the most efficient attractive method for oil and gas transportation. Pipelines are also the most economical method used nowadays for trans- porting any type of fluid. However, the capital cost for crude trunk pipelines is very high, depending on the pipeline steel grade, the design wall-thickness, and the length of the pipeline. These factors often force the product owners to construct most of the cross-country pipeline network in a single channel, making it difficult to shutdown for inspection, maintenance, or repair. In addition, the major part of the cross-country pipelines are buried and excavation is precluded. Likewise, offshore pipe- lines are extremely difficult to inspect, maintain, or repair due to deep-water factors and low-density environment. inspection for integrity of pipelines is often conducted from the inside using an intelli- gent pigs with the capability of measuring any losses in the pipe wall thickness in the form of flaws, cracks, or corrosion damages while traveling inside the pipeline. nowadays, new era of smart pigs for both; out-of-service and in-service pipelines have been developed/invented to perform an in-si- tu repair of these defects on the internal pipe surface before they reach a critical size and become hazardous to operation & safety. This paper will discuss the new era of the intelligent pigs and the benefits of carrying more developments in such tools. of In-line Inspection (IlI) > by: hamad Almostaneer, SABIC JUBAiL SAUdi ARABiA Pipeline corridors at king Fahad industrial Port. abstract Intelligent Pigs for Internal Inspection & Repair welding of cross-country Pipelines 60 PiPeLine TeCHnoLoGy JoURnAL RESEARCH / DEVELOPMENT / TECHNOLOGY inTRodUCTion Pigging of a pipeline refers to the use of a Pipeline Inspection Gauge or “PIG” to perform various maintenance operations on a transmission, onshore, and offshore pipeline. This usually is done without stopping the flow of production in the pipeline. These maintenance operations include but are not limited to either cleaning, or inspection, or both of a pipeline. this practice is achieved by inserting a pig into a “pig launcher” or a launching station. It is a funnel shaped Y in both end-sections of the pipeline. The launcher is then closed and the pressure-driven flow of the product in the pipeline is then used to push it along down the pipeline length until it reaches the “receiving trap” or a receiving station as shown in Figure 1 [1,2,3]. One of the most crucial aspects of pipeline operation is ensuring the pipeline integrity. For this reason, in-line inspection (IlI) pigs have be- come important. the Intelligent Pigs “smart pigs” are important tools for assessing the integrity conditions of a pipeline, and is set to become more integral part of the pipeline maintenance. Nowadays, more devel- opments are made towards solving the integrity issues of Unpiggable pipelines [2,3]. PiPeLine PiGGinG SySTeMS a Pipeline Inspection Gauge or “PIG” in the industry is a tool that sent through a pipeline and propelled by the internal pressure of the product in the pipeline itself. therefore, pigging operations are mostly performed for in-service pipelines. there are four main uses for pigs: 1) Physical separation, 2) Internal cleaning, 3) Inspection of the internal condition, also known as an Inline Inspection (IlI) operations, and 4) capturing and recording geometric information related to the pipelines (i.e. size, position, thickness loss, corrosion, etc.). Depending on the type of pig, it can perform one or a number of spe- cific tasks including [3,4]: 1) Cleaning debris from the pipeline, 2) Re- moving the residual products that accumulate with time, 3) Gauging the internal wall of a pipe to locate defects, 4) assessing the condition and location. however, pipeline pigs can also be used for other pur- poses. these include but not limited to: 1) hydrostatic testing, 2) air/ nitrogen removal from the pipeline, 3) Batch separation in case of using the same cross-country pipeline to batch multi-products, 4) Pre-inspec- tion and certification of newly constructed pipeline, 5) Integrity assess- ment of an in-service pipeline, 6) Decommissioning unsafe pipeline for environment purposes. Nonetheless, the pigs can only be one of two main types: 1) Utility pigs, or 2) Intelligent pigs, also called smart pigs as mapped in Figure 2 [1,3]. however, since the utility pigging technology is relatively old and simple to deal with, this paper will focus more on the intelligent pigs. THe oRiGinS oF inTeLLiGenT PiGS indUSTRy In 1959 five decades ago, T.D. Williamson introduced the first “caliper tool” for detecting dents in pipelines. Pan-american Petroleum was de- veloping a “cooley tool” around the same time, which used the Magnet- ic Flux leakage (MFl) technique. In 1961, Shell Oil Research developed a technique for detecting pitting corrosion in down-hole casings based on a “Maclean tool”, which worked with a Remote Field eddy current (RFec) [1,2,3]. In 1962, tuboscope obtained a licence from Shell Oil Research for the Maclean tool and started developing a smart pig to carry an array of remote field eddy current sensors through a pipeline. Early test runs with the Maclean tool were unsuccessful, as they could not detect known pits in the test spools. tuboscope then approached Pan-american Pe- troleum and purchased the cooley tool patent. the Maclean tool was discarded and the smart pigging developments switched to cooley tool or as known today as MFl technique. the new tool was branded lIN- alOG® [1,2,3]. In 1964 Tuboscope ran the first commercial instrument for the new LIN- alOG 90° tool. It used MFl technology to inspect the bottom portion of the pipeline. the system used a black box to record the information, a highly customized analog tape recorder. This first commercial job was for Shell company [1,2,3]. “INTEllIGENT PIGS INDUSTry CoNTINUED To Grow” > hamad Almostaneer Figure 1: Pig station a pig launcher/receiver, for Natural Gas Pipeline in Switzerland PiPeLine TeCHnoLoGy JoURnAL 61 RESEARCH / DEVELOPMENT / TECHNOLOGY Utility Pigs cleaning Pigs Sealing Pigs Brush Pigs Mandrel Pigs Plugs Scraper Pigs Foam Pigs Dependet hydraulic Pigs Solid cast Pigs hydraulic activated Spherical Pigs Inline-Inspection tools (IlI) Inline-Inspection (IlI) Smart Pigs IlI Geometry Pigs Gel Pigs Figure 2: an overview map of the available tools for both 1) Utility pigs, and 2) Intelligent pigs. 62 PiPeLine TeCHnoLoGy JoURnAL THeoRieS oF inTeLLiGenT PiG TooLS Intelligent pigs are highly specialized tools for in-line inspection (IlI) which can detect, locate, and size flows in pipelines. There is no tool that can be used for all inspection purposes as each tool uses different physics and principles. however, each inspection tool must be selected accordingly and the ability of the used tool must correspond to the in- spection requirements [4,5,6]. However, the difference between different tools can be identified due to the measurement accuracies and the detection threshold. the follow- ing tools will focus on in-line inspection (IlI) tools and techniques that are used within intelligent pigs to detect, size, and locate flaws that are reached subcritical sizes [7,8,9]. MAGneTiC-FLUX LeAkAGe TooL The magnetic-flux leakage (MFL) method can be used to measure and locate cracks and metal-loss in both circumferential and axial directions. It is a popular method for inspecting pipelines for both stress sensitivity or levels and corrosion defects and characterization. The magnetic-flux leakage (MFl) work principle is shown in Figure 3 [10,11,12]. AXiAL MAGneTiC-FLUX LeAkAGe TooL this type of tool usually consists of a central body of mild steel around which is mounted an annular arrangement of magnets. these magnets spread from center outwards in a radial arrangement to give opposing poles on either end of the body (north or south) as shown in Figure 4. there are steel bristles which create contact with the pipeline wall, to complete the magnetic circuit and allow the inspected pipe section to be uniformly magnetized in the axial direction as the tool passes down the line. If the pipe is not corroded, the magnetic flux will be locked-up within the steel pipe wall. however, corrosion or any other feature such as flaw will cause flux to leak out of the pipe wall which then can be detected by the circular array of the magnetic sensors [13]. this type of tools is directly related to the crack detection where axial MFl tool can detect crack geometries at right angles to the induced magnetic field such as cracks in girth welds [14,15]. Figure 3: Magnetic-flux leakage working principle: a pipeline with a perfect wall. Figure 4: Axial magnetic-flux leakage system. RESEARCH / DEVELOPMENT / TECHNOLOGY TRAnSveRSe-FieLd MFL TooL MFL tools are good to detect flaws which are located at the angles to the induced magnetic field. Axially-oriented narrow flaws are hard be detected by the axial MFl. however, these narrow, long defects are serious threat to the transfer pipelines integrity especially metal-loss flaws and cracks in longitudinal seam welds of a pipeline. They can cause failures during operation to in-service pipelines. the occur- rence of the long axial defects led to the development of MFl sys- tem incorporating transverse magnetic field. The schematic of such system is shown in Figure 5A. In theory, applying magnetic field in a transverse direction around a pipeline makes it easier to differentiate and characterize defects orthogonal to the field (long axial defect) [14,15,16,17]. ULTRASoniC TooL the major advantage of ultrasonic technique is the ability to provide quantitative measurements of a wall of a pipeline. the high accuracy levels make it an ideal ILI tool. UT inspection tools are fitted with suf- ficient number of ultrasonic transducers to ensure full circumferential coverage of a pipeline. the transducers operate in an impulse-echo mode. this means that they switch from being emitters of an acous- tic signal in the ultrasonic sound range to being receivers [17,18,19]. It is often done by determining the pulse repetition frequency. the sensor emits an ultrasonic signal that is partly reflected at the inter- nal wall surface and partly at the external wall surface of a pipeline. The first reflection provides a measurement of the stand-off distance and the second value for the wall thickness as shown in Figure 6. as the tool travel through pipeline, the sensor takes measurements at regular intervals, set by the traveling speed of the tool which later analyzes the whole pipeline length [17,20]. AnGLe-BeAM ULTRASoniC TooL an ultrasonic crack-detection tool utilizes angled-beam probes. the tool is designed to detect and size axial crack in a pipeline wall and long-seam weld joints. It also detects stress-corrosion cracking (SCC). The ultrasonic sensors are fixed at an angle to the wall at un- der a 45° angle which is optimum for crack detection. Depending on the tool size, this tool can have up to above one thousand ultrason- ic transducers. Minimum detection threshold for this tool is 30 mm crack length and 1 mm crack depth. circumferential cracks can also be detected but it would require modified sensor carrier which have to be turned by 90° angle. however, this tool as shown in Figure 7 successfully detected stress-corrosion cracks (Scc) [17]. The lower part of the picture shows the actual flaws and the up- per-part are the displayed data by the Ut tool. Nonetheless, detection accuracies, high confidence levels of detection, sizing, and repeata- bility are the main characteristics of ultrasonic IlI tools [17]. WALL-THiCkneSS-MeASUReMenT ULTRASoniC TooL this type of ultrasonic tools is used for metal-loss measurements. It can be identified by the alignment of the ultrasonic sensors that are mounted at 90° angle to the wall. Figure 8 shows the physical princi- ple for this tool. Ultrasonic transducers emit a signal directed to the internal surface of a pipeline wall and part of the signal is reflected and received by transducers. the other part of the signal that travels through the pipe wall is reflected back by the external surface of the wall. the signals of this part are also received back by the transduc- ers and provide wall-thickness measurement. this ultrasonic tool be- sides the function of wall-thickness measurements is ideal for flaws that are present inside the pipeline wall such as hydrogen-induced cracks and inclusions [17]. eddy-CURRenT TooL eddy current inspection tool is another IlI-NDt tool that uses the principle of electromagnetism as the basis for conducting measure- ments. eddy currents are created through a process called electro- magnetic induction by applying an alternating to a conductor, such as a copper wire, a magnetic field will develop in and around the con- ductor. This magnetic field expands as the alternating current rises to maximum and collapses as the current is reduced to zero [21]. Figure 9 shows the principle of the eddy current sensor inducing a primary field, according to Lenz Law, 90° angle to the original field lines of the coil. Due to further induction of the eddy current in the primary field of the electric conductive material, a secondary field is induced which will effect the coil impedance. In case of a defect in the tube wall, the secondary field is changed in comparison to its or- igin. The change of the Eddy Current field lines causes a change of the impedance of the eddy current probe coil, which is related to the defects [22]. A remote field eddy current (RFEC) that uses a low fre- quency ac and relatively large exciter coils has become an excellent NDt technique to detect cracks of internal wall of pipes and tubes as shown in Figure 10 [23]. Figure 5: transverse MFl tool: a) Schematic of the magnetization arrangement for transverse-field, and B) Transverse field tool capable of detecting cracks (courtesy for tranScan). 64 PiPeLine TeCHnoLoGy JoURnAL RESEARCH / DEVELOPMENT / TECHNOLOGY Figure 5: transverse MFl tool: a) Schematic of the magnetization arrangement for transverse-field, and B) Transverse field tool capable of detecting cracks (courtesy for tranScan). Figure 6: the principle of ultrasonic technique measurements. Figure 7: Stress-corrosion cracks (Scc) detected by angled-beam ultrasonic tool. PiPeLine TeCHnoLoGy JoURnAL 65 RESEARCH / DEVELOPMENT / TECHNOLOGY Feedstock Pipelines neW eRA oF AdvAnCed iLi inTeLLiGenT PiGS Intelligent pigs industry continued to grow due to the demands of increasing safety and reduce costs in maintaining transmission, on- shore, and offshore pipelines. Osaka Gas studied various types of robots capable of inspecting and repair welding pipelines from in- side, and have succeeded in developing automatic welding robots to reinforce welds from the inside of a steel pipeline. The configuration of one of Osaka Gas systems is shown schematically in Figure 11 [24]. the principle of the welding monitor, however, is all welding work is remote-controlled above ground. the torch is controlled with four axes, whose movement is programmed in a specified sequence. The welding conditions can be monitored via two tv cameras. If exces- sive spatter is deposited on the torch nozzle, the nozzle then can be automatically cleaned with a spatter remover as shown in Figure 12. however, application of this repair method to the inside of an in-ser- vice pipeline would require that welding be performed in a hyperbaric environment or to take the pipeline from service/operation [24]. colorado School of Mines (cSM) invented a method that can be developed within an intelligent pig system to perform in-situ crack detection and repair welding internally, using the Maw-UO process on the internal pipe surface of in-service pipeline. likewise, the sys- tem configuration module of the welding unit that carries the torch of MAW-UO process, NDE tool, grinding, and finishing tools connected to other controlling units on board to travel inside a defective pipeline that has flaws, cracks, or corrosion damage to be repaired is shown schematically in Figure 13 [25]. the concept of the MawUO welding unit is to have an integrated robot to remotely locate of some widely dispersed perforations in the pipeline using remote laser profillometry (precision laser surface mapping followed by analytical form fitting). Then, eddy-current char- acterization of the defected areas and a remote positioning and repair welding of a patch, followed by inspection. the weld metal buildup or overlay and finally the inspection all should be remotely controlled with full vision and laser positioning as shown in Figure 14 [25]. there are no technical limitations to these repair methods to the in- side of either an out-of- or in-service pipeline. It is direct, inexpensive to apply, and requires no additional materials beyond welding con- sumables. typical system can be as schematically shown in Figure 15 [24]. Figure 8: wall-thickness-measurement ultrasonic tool working principle. Figure 9: Principle of eddy current. 66 PiPeLine TeCHnoLoGy JoURnAL RESEARCH / DEVELOPMENT / TECHNOLOGY SUMMARy the in-line inspection intelligent pigging of pipelines have grown tre- mendously in the last five decades and progressed from utility pigs that are used for cleaning, to smart pigs that are used for inspection purpos- es, and today to in-situ repair smart pigs. the inspection/repair of pipelines using intelligent pigs is now well established, and interests are growing in the use of this versatile tech- nique. Intelligent pigging tools offers a viable alternative to traditional, manual inspection techniques with several significant advantages. Figure 10: Remote Field eddy current (RFec) inspection technique. Figure 12: Schematic of the welding unit. Figure 11: Osaka Gas co./Sumitomo Metal Model; Internal welding Robot system. PiPeLine TeCHnoLoGy JoURnAL 67 RESEARCH / DEVELOPMENT / TECHNOLOGY Figure 13: colorado School of Mines Module; In-Situ Repair welding Robot. Figure 15: System configuration of intelligent pig for repair welding.Figure 14: 3D view of MawUO process welding unit. Author dr. Hamad H Almostaneer Scientist, Materials, Corrosion & Static Equipment Domain Mcc SaBIc, Saudi Basic Industries corporation Jubail, Saudi arabia mostaneerhh@SaBIc.com +966 (13) 359 9129 References [1] woodley, D; “the origin of intelligent pigs”; Pipelines International (2011) [2] PM Pipeliner; “Pigging and Developments”; www.pm-pipeliner.safan.com (2014) [3] Al-Jafar, M.; and Almostaneer, H.; “The Efficiency of NDT Techniques on In-Line Inspection (ILI) for Pipelines Internal Inspection”; aMPt conf. Proc., Dubai, Uae (2014) [4] Mohitpour, Mo et al.; “Pipeline Operation and Maintenance: a Practical approach”; 2nd edition; aSMe Press., New York, NY (2005) [5] Mohitpour, M. et al.; “Pipeline System Design, construction and Operation Rationalization”; aSMe 14th OMae conf. Proceedings (1995) [6] almostaneer et al.; “In-situ repairs of pipelines using metal arc welding under oil (Maw-UO) aided by eddy current crack detection”, aIP conf. Proc. 1430, 1243 (2012) [7] Bruce, w. a.; “a Simple approach to hot tap and Repair Sleeve welding”; wtIa Int. Pipeline Integrity conf. Proceedings (2005) [8] Gordon, J. R., Bruce, w. a., Sullivan, M., and Neary, c. M.; “Internal Repair of Pipelines -technology Status assessment”; U.S. Department of Energy; Edison Welding Institute and Pacific Gas & Electric (2002) [9] Process Piping Design handbook; “the Fundamentals of Piping Design”, vol. 1; Gulf Pub. co.; houston; tX (2007) [10] Ramuhalli, P.; et al.; “electromagnetic NDe Signal Inversion by Function approximation Neutral Networks”; Ieee trans. Magazine; vol. 38 (2002) [11] Ivanov, P.a.; et al.; “Magnetic Flux leakage Modeling for Mechanical Damage in transmission Pipeline”; Ieee trans. Magazine; vol. 34 (1998) [12] Atherton, D.L.; “Effect of Line Pressure on the Performance of Magnetic Inspection Tools for Pipelines”; Oil and Gas Journal; vol. 84 (1986) [13] Mandal, K.; et al.; “the Study of a Race-track-Shaped Defect in Ferromagnetic Steel by Magnetic Barkhausen and Flux leakage Measurements”; Journal Magnetism Magnet. Mater.; vol. 212 (2000) [14] Beller, M.; et al.; “On the Problem of Detecting and assessing cracks in Pipelines”; OMae Int. conf. Proceedings; Stavanger; Norway (1991) [15] Bal, c.; “New transverse Flux technology for On-line Inspection”, IBID (2002) [16] Reber, K.; and Beller, M.; “How Do Defects Assessments Methods Influence the Design of New In-Line Inspection tool”; Pipeline Rehab. and Maint. 5th Int. conf. Proc., Bahrain (2002) [17] Tiratsoo, J.; “Pipeline Pigging & Integrity Technology”; 3rd edition; Scientific Surveys Ltd & Clarion Pub. (2003) [18] cordell, J.; and vanzant, h.; “all about Pigging”; On-Stream Systems; UK (1995) [19] Beller, M.; et al; “Getting ahead with Ultrasound”; world Pipelines (2006) [20] Reber, K.; et al.; “advances in the Ultrasonic In-line Inspection of Pipeline”; 3R-International; Special edition (2004) [21] Bray, D. e.; and Stanley, R. K.; “Nondestructive evaluation: a tool in Design, Manufacturing, and Service”; cRc Press; New York; USa (1997) [22] Reber, K.; “Innospection Germany Gmbh, Stutensee, Germany, the PPSa Seminar”; a.Bönisch, Innospection ltd.; aberdeen; UK (2010) [23] Osagawa, a.; “an internal welding robot system for 600 mm steel pipelines”; pp. 175-182; Proceedings of the 6th ISaRc; USa (1989) [24] atherton, D.l.; et al.; “Remote Field eddy current Inspection techniques for Metallic tubes”; Ph.D. thesis, Queens Univ., Kingston, ca (2006) [25] al-Mostaneer, h.; and Olson, D.l.; “In-Service weld Repairs Using Metal arc welding Under Oil (MawUO) Of Pipe- lines, tanks, and vessels”; Patent; US 20120111837 (2012) 68 PiPeLine TeCHnoLoGy JoURnAL By offering the complete range of project life-cycle services, ILF Consulting Engineers provides the best techno-economic solution for our customers, with proven excellence on early project phases. For project management, engineering, consulting and field services, ILF is your trusted advisor for oil & gas pipeline projects. Do your projects require large diameter, long distance pipelines? Does your routing include challenging terrain and difficult soil conditions? We are able and willing to tackle the most challenging boundary conditions for optimizing and designing the most technically demanding pipeline systems in the world. Family owned and managed, ILF is a completely independent enterprise. Our values are not driven by stock price performance. Continuous growth for almost 50 years and thousands of successful international projects must be a clear testimony of customer satisfaction. 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KG · Paul-Schmidt-Straße 2 · 57368 Lennestadt · Germany · www.TRACTO-TECHNIK.com June 8-10, 2015 Berlin PIPelINe SeMINaRS 11-12 JUNe 2015 IN BeRlIN, GeRMaNY Seminar Microbiologically influenced corrosion (MIC) and its impact on pipeline corrosion management 11-12 June 2015 Estrel Berlin Berlin, Germany organized by a Pipeline Technology Conference eventPipeline Technology Conference 2010 Euro Institute for Information and Technology Transfer Seminar Geohazards and Geotechnics in Pipeline Engineering 11-12 June 2015 Estrel Berlin Berlin, Germany organized by a Pipeline Technology Conference eventPipeline Technology Conference 2010 Euro Institute for Information and Technology Transfer Seminar In-Line Inspection of Onshore and Offshore Pipelines 11-12 June 2015 Estrel Berlin Berlin, Germany a Pipeline Technology Conference eventPipeline Technology Conference 2010 Euro Institute for Information and Technology Transfer organized by In-Line Inspection of Onshore and Offshore Pipelines the course will provide an in-depth introduction into the subject and importance of pipeline inspec- tion and integrity management. Delegates will learn about the need for pipeline inspection and the use of inspection for the analysis of the pipelines integ- rity and fitness-for-purpose. The course will introduce the flaws and anomalies observed in pipelines. Suitable external and internal inspection technologies will be introduced includ- ing the strength and weaknesses of the non-de- structive testing principles applied. the material cover details on a pipeline inspection operation, including pipeline preparation, cleaning, gauging. Final Reports, Reporting Formats are discussed. the course also includes a short introduction into integ- rity assessment. Geohazards and Geotechnics in Pipeline engineering the course will provide an in-depth introduction into the subject and importance of Geohazards and Geotechnics during the stages of evaluation, de- sign, construction and operation of a pipeline. Delegates will learn about the need for Geohazard assessment and Geotechnical engineering in rela- tion to the route selection and the pipeline integrity. additionally, potential protection measures and/or monitoring techniques will be presented. the main disciplines that will be presented during the course are engineering Geology, Soil Mechan- ics, and Rock Mechanics, while special emphasis will be given on Slope Instabilities and Stabilization Methods. Since many countries worldwide are characterized by moderate or high seismicity, the course will also introduce the topics of Geotechnical earthquake engineering and Pipeline Seismic Design. Microbiologically influenced Corrosion (MIC) and its impact on pipeline corrosion management engineering importance is a function of cost and risk. cost of corrosion is about 5% of the GDP of a country and microbial corrosion (MIc) accounts for about 1/5 of the corrosion cost. In addition to cost, what makes it even worse is that a great number of MIc cases are mistakenly attributed to corrosion phenomena other than microbial corrosion. In en- gineering terms, “Risk” is defined as the product of “likelihood” and “consequences”: no matter how low the likelihood, as the consequences could al- ways be critical, the risk of MIC is classified as “ex- tremely high”. almost all engineering materials are susceptible to microbial corrosion. corrosion- re- lated bacteria can tolerate a wide range of ph and temperatures. a combination of the above factors makes MIc a very dangerous factor that must be dealt with meticulously. MIc can be observed in a wide range of industries from mining, oil & gas, pow- er generation to marine industry, chemical industry and even in ships and in systems such as hydrants and pipelines. Further information: www.pipeline-conference.com Play video CONFERENCES / SEMINARS / EXHIBITIONS 70 PiPeLine TeCHnoLoGy JoURnAL www.clarion.org 8–11 February 2016 | Houston, Texas, USA Now entering its 28th year, the PPIM Conference is recognized as the foremost international forum for sharing and learning about best practices in lifetime maintenance and condition-monitoring technology for natural gas, crude oil, and product pipelines. To secure an exhibition space, sponsorship, or for more information, contact: Traci Branstetter traci@clarion.org or +1 713 449 3222 PLATINUM ELITE SPONSOR ORGANIZED BY ® ® February 8–11, 2016, Houston 28YEAR 2016 th PPIM16_FP_A4_EITEP.indd 1 23/04/2015 4:54 pm looking ahead. We plan for the future. More than one-third of ROSEN employ- ees work in research and development, creating innovative products needed by the industry. An invest ment, we are proud of. www.rosen-group.com Play video