0 2 0 2 / 2 e u s s I e Journal Pipeline Technology Journal 2ND SPECIAL EDITION PIPELINE TECHNOLOGY CONFERENCE www.pipeline-journal.net ISSN 2196-4300
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PIPELINE TECHNOLOGY JOURNAL 3 EDITORIAL Dear colleagues, Today you receive the 2nd edition of ptj, with which we publish the presentations of the “Pipeline Technology Conference”, ptc, which was cancelled due to the corona epedemia. The third special issue with the remaining 20 papers will be published soon. The online ptc 2020 as a replacement has brought a surprisingly positive response. The repayment of the remaining participant payments was completed with a great deal of understanding and consideration from sponsors, exhibitors and participants. One could say that with the help of the ptc family we have survived this great crisis without any major losses in terms of costs and performance. We would like to thank all those who have contributed to this. Nevertheless, none of us can carry on as before, because the corona crisis has shown the whole world that in globalisation it is no longer only safety, reliability and profitability that count. Environmental protection, social equilibrium and health protection are also clearly important. Specialist conferences with large international participation are affected to a considerable extent. On the other hand, however, the international exchange of experience is so important, especially in the pipeline sector, which is why in future - where it is possible and appropriate - much more exchange will probably take place digitally using the Internet. At EITEP, a team led by Dennis Fandrich, Director Conferences and Marian Ritter, Director Exhibitions, is currently developing an online conference format which, like a presence conference, will allow all participants to exchange experiences and compare the services and products presented. The first “Virtual Pipeline Summit”, VPS which deals with the complex “Digital Transformation in the Pipeline Industry”, will be offered on 30. 6. 2020. Shortly after its publication, well over 450 participants from more than 60 countries had already registered. As with ptc, 28% of them are from operators. Dr. Klaus Ritter Editor in Chief Dennis Fandrich Director Conferences It is hoped that this format will meet the expectations of the ptc family. Other topics, services and technologies will be covered in further VPS events. Marian Ritter Director Exhibitions Of course, the 16th ptc, which brings together the entire spectrum of the pipeline industry, will again be held in Berlin from 15 to 18 March 2021. Sincerely yours Dr. Klaus Ritter, President, EITEP Institute
4 PIPELINE TECHNOLOGY JOURNAL THIS ISSUE’S COMPLETE CONTENT SECOND SPECIAL EDITION WITH PTC PAPERS JUNE 2020 / SPECIAL EDITION Cost-effective Ultrasonic Inspection of Large Diameter Pipelines: Technology Update Ries Augustijn - Intero Integrity Services North Sea Wintershall DEA Case Study Christoph Seeber; Holger Hintelmann - NDT Global GmbH & Co. KG; Wintershall DEA AG Quantitative Pipeline Risk Assessment (QPiRATM) Fire and Dispersion Analysis of a Subsea Gas Pipeline Leak Using Empirical Consequence Modelling M Nazmi B M Ali Napiah, Shaikh Abdullah B Shaikh Othman, Aishah Mastura Supian - PETRONAS, Malaysia 8 18 28 OMEGA Fiber Optic Monitoring System: New Features for Technological Security of Transneft Pipelines Dr.Aleksey I.Turbin - OMEGA 36 Enhancing Energy Efficiency and Reducing Greenhouse Gas Emissions through Innovation and Renewables Integration E. Nasini, M. Santini, M. Baldini, S. Amidei, M. Vaccaro - 40 Baker Hughes Real-time remote monitoring and risk management of oil & gas facilities subjected to natural hazards P. Psarropoulos, E. Kapogianni; Y.Tsompanakis - National Technical University of Athens; Technical University of Crete 50 GRP Piping Failures Ali Assi - Amiantit Qatar Pipes 58 Prediction of Leak Mass Rate in High-Pressure Gas Pipeline F. Yuan, R. Chen, B. C. Khoo; Y. Zeng; R. Luo - National University of Singapore; National Metrology Centre, Singaproe; Xylem Inc 72 THANKS TO THE PTC-COMMUNITY 80 Company Directory Page 82 ptc Review 78 Event Calendar 87 Pipeline Technology Journal - ptj @pipelinejournal ence www.pipeline-journal.net Pipeline.Technology.Confer-
GERMAN MUSICIAN CREATES A PIPELINE SYMPHONY It takes a certain genius to use an object for a completely different pur- pose than the one for which it was originally intended. And so it is with Armin Küpper from the small German town of Liedberg in North Rhine Westphalia. Küpper is a musician. Plays the saxaphone. But he has discovered a unique way to enhance the human sound of his instrument: Küp- per plays next to large gas pipes allowing the sound of the sax to be hauntingly amplified by the natural echo the pipe produces. This is the advantage of living in a town like Liedberg, he says, where there are an abundance of pipes positioned along the pipeline right-of-way waiting to be laid. “Sometimes I just can’t stop playing. The nice thing is, when it gets cool in the evening, I sit down in the pipe still warm from the sun’s rays during the day and enjoy the sunset playing the saxophone.” www.pipeline-journal.net/news/german-musician-creates-pipe- line-symphony
Cost-effective Ultrasonic Inspection of Large Diameter Pipelines: Technology Update Ries Augustijn > Intero Integrity Services Abstract To be successful in the ILI business, organization require the right mix of technological capabilities, operational agility and quality standards. The business is fairly competitive, and often technological capabilities are pivotal in the customer proposition of the company. However, the best technologies are not solely required for successful ILI companies. Robustness of the system, operability by the ILI inspector, fitness of the product with commercial route to the market all contribute to a rapid return on investment. Within Intero Integrity we have a diverse innovation portfolio, focused at unpiggable pipelines and robotic tank inspections. Providing a robust, versatile, high-resolution and cost-effective method to inspect large diameter pipelines was recognized as a challenge and opportunity. For that, Intero has developed a Large Diameter Ultra- sonic Inspection tool capable of inspecting pipelines of 20 inch to 64 inch with high resolution. The tool is always bi-directional and capable of mitigating 1.5D bends. Gathered data can be reviewed real-time during the inspection. The operating envelope of the tool is such that it can cope with various products in the pipeline, varying from (high salinity) water, crude oil and a multitude of refined products. Despite the fact that product properties (e.g. speed of sound, attenuation, temperature, etc) vary, the tool is designed such that this is not a limiting factor for the oper- ating envelope. The application of advanced ultrasonic beam forming methodologies and signal generation and -processing ensure that the system is versatile and robust for these types of real-life operating conditions. This presentation will provide an overview of the utilization of these technologies, the validation program that has been used to demonstrate tool specifications and the experiences gained at successful projects.
RESEARCH / DEVELOPMENT / TECHNOLOGY PIPELINE TECHNOLOGY JOURNAL 9 INTRODUCTION Pipeline infrastructures play an important role in our to- day’s society. Economically and politically, the dependency of our community strongly depends on pipeline networks. Operating pipelines introduce risks to health, safety, envi- ronment and economics. Hence, managing these risks is essential. Managing these risks comprises various activities, of which inspection and Non-Destructive-Testing (NDT) is a significant part. Intero Integrity (formerly A.Hak Industrial Services) is an inspection and industrial services specialist, combining innovative technologies, critical insights, state- of-the-art equipment and advanced data management with a streamlined project approach. A wide range of inspection tools is available in the market, deploying various technologies, in different ways. Among others the deployment of “Intelligent Pigs”, allow to use advanced electronics and sensorics to assess the pipe- line integrity, Various NDT methods & techniques can be utilized, among others Ultrasonic Testing. The cost-effective ultrasonic inspection of large diameter pipelines has been a challenge for decades in our industry. Intero Integrity has been working on an improved inspec- tion system for this case. PROBLEM STATEMENT AND SYS- TEM REQUIREMENTS pipelines. In the range of services provided, the inspection of large pipelines presents several technical and operation- al challenges. To enable inspection of these pipelines, clients frequently require the inspection to be conducted without exposing their pipelines to a different product. This presents several challenges as these large pipelines may contain multiple liquid products at different temperatures, and frequently their acoustic properties cannot be characterized prior to inspection. Characterizing the acoustic properties beforehand is typi- cally only possible for some pure refined products, while in other, e.g. crude oils, it is not possible because of the wide variation produced from different oilfields or various blends available and furthermore their properties can vary signifi- cantly due to the temperature of the inspection medium. OBJECTIVE The main objective was to develop a flexible, safe and cost-effective system based on Ultrasonic Testing, that could work in various inspection media (products) and increase the sensitivity and resolution of existing tools and be capable of inspecting pipelines ranging from 20 inches up to 64 inches with a formfactor of a typical bidi cleaning pig. SYSTEM DESCRIPTION SCOPE Intero operates inspection tools based on Ultrasonic Testing (UT) to determine the remaining wall thickness of This inspection system relates to thickness measurement through the Phased Array Ultrasonic Testing (PAUT); en- abling corrosion mapping of pipelines. Figure 1: LDUT Piglet®
10 PIPELINE TECHNOLOGY JOURNAL RESEARCH / DEVELOPMENT / TECHNOLOGY The concept is based on the standard Intero Piglet® system, deploying an autonomous pigging system, with an optional optical fiber tether to allow for real-time data review during the inspection. However, it is improved with an annular ultrasonic Phased Array transducer enclosed in a spherical housing. The rotatable mirror arrangement based on the Internal Rotating Mirror Principle (IRIS) allows the pipe to be investigated 360° degrees with an adjust- able measuring grid. Some of the benefits of Phased Array technology over conventional UT derive from the ability control beam shape on transmission and increase the sensitivity on reception. Annular array transducers have unique characteristics which make them superior for this application as they can focus at a predetermined distance producing a symmetric and circular beam profile. Crude oils however are typically attenuative media which exhibit a natural high frequency filtering effect. Conven- tionally, overcoming the frequency dependent attenuation effects was done by outputting more energy, lowering the inspection frequency and transmitting a longer pulse at the cost of lowering the axial resolution. Traditional single-pulse excitation can be replaced by long coded pulse excitation, which can extend the pulse dura- tion instead of increasing the signal pulse amplitude. In this way, the average transmitting energy can be increased, overcoming severe attenuation by the inspection medium. The application of frequency modulation signals, also known as “chirps”, consist of transmitting a wide band frequency modulated signal that is cross-correlated with a reference in order to be able to resolve in time the returned echoes. The correlation process restores axial resolution and increasing SNR. The “chirp” signals are also less susceptible to the influ- ences of coatings, contaminants, debris or impurities in the product. The signals applied are dependent on the application and the transducer used. In some applications the broadband electrical signal applied to the transducer includes energy up to 10MHz, for other applications, the energy may be restricted to 3.5MHz or less. PERFORMANCE SPECIFICATIONS (POF 2016) The Pipeline Operators Forum (POF) 2016 and the API1163 standard provide guidelines for defining the basis of per- formance specification of ILI systems. The performance specification was made by modelling and pull through tests. Statistical analysis of the data was done with STA- TUS 5 Eclipse Scientific software. MODELLING Simulations in CIVA software were performed to provide constructive delay laws and beam computations to enable to cope with the multiple materials and the complex geom- etry of the prototype concept. Beam computations were performed for different media and pipelines diameters and the correspondent beam profile was assessed in pre-de- fined computational areas. (Figure 2) Figure 2: Example of computational areas (IW plane) In the images on the right (Figure 3) we can visualize the radiated ultrasonic field by the developed tool in a low velocity medium, i.e. Naphtha @ 1130 [m/s].
RESEARCH / DEVELOPMENT / TECHNOLOGY PIPELINE TECHNOLOGY JOURNAL 11 Figure 3: Ultrasonic Field (L-Wave); (A) - Null delay (unfocused); (B) - 100 [mm] focal point; (C) - 200 [mm] focal point; (D) - 300 [mm] focal point; (E) - 411 [mm] focal point (BW) 30 inches. Figure 4: Computational plane placed on the BW of a 28 inches pipe (Beam profile @ -6dB), in this example the focal point is placed on the back-wall (I); +100mm from the back-wall (H); +200mm from the back-wall (G); and +300mm from the back-wall (F).
12 PIPELINE TECHNOLOGY JOURNAL RESEARCH / DEVELOPMENT / TECHNOLOGY This beam energy mapping shows the zones of maximum energy of the beam within the defined computational area (Naphtha @ 1130 [m/s]) . The developed system can extend the operating envelope to lower velocity media. Therefore, the diameter of the UT beam at pipe surface can be established according to the inspection requirements, figure 4 shows an example through a computation plane placed on the back-wall of a 28in pipeline, with Light Crude Oil @1350m/s. PULL-THROUGH TESTS In March of 2018, pull through tests were performed in order to establish the performance specification on a 28 inches carbon-steel test pipe spool with artificial manufac- tured Pinhole and Pitting type of defects, having medium density crude oil, API gravity 26, as a inspection medium. Metal losses are represented by two types of geometries: Flat Bottomed Holes (FBH) and Hemispherical Bottomed Holes (HBH) (Table 1). The figure 5, shows the test setup for the pull-through tests. 12 runs were performed at an inspection speed of 100 [m/h]; 470 measurements per revolution enabling a Figure 5: Pull-through test setup Table 1: 28 inches Test Pipe Overview
14 PIPELINE TECHNOLOGY JOURNAL RESEARCH / DEVELOPMENT / TECHNOLOGY Figure 6: Data Acquisition C-scans measuring grid of approximately 4.6 x 4.2 [mm], circumfer- ential and axial, respectively. Sizing of the detected flaws was performed by Data Ana- lysts. Figure 6 on the right shows the C-scan images of one of the pull-through runs performed. POD AND SIZING CURVES The Probability Of Detection, POD, is the probability that a feature with size a will be detected by the ILI tool. Accord- ing to the POF “Specifications and requirements for in-line inspection of pipelines” version 2016, two features can be extracted: • A 90/50 (a90) is the feature size at which the average POD is 90%; • A 90/95 (a90/95 is the feature size at which the lower 95% confidence limit of the POD is 90%). Figure 7: POD Curve for HBH’s Table 2: POD (a90 and a90/95) Pipeline Technology Journal Register for free & join 30,000 verified recipients! Stay up-to-date with the ptj - newsletter
RESEARCH / DEVELOPMENT / TECHNOLOGY PIPELINE TECHNOLOGY JOURNAL 15 Figure 8: Sizing accuracies for FBH (left) and HBH (right)
16 PIPELINE TECHNOLOGY JOURNAL RESEARCH / DEVELOPMENT / TECHNOLOGY All Metal losses, represented by FBH’s, were detected in all the runs. These are not taken into account in the below graph. The two smallest Hemispherical Bottom Holes were not detected both internal and external, (Figure 7). SIZING ACCURACIES The sizing accuracy results are depicted in Figure 8. Regarding metal losses, for FBH, the tool has a depth sizing accuracy of ±0.1[mm], length sizing accuracy of ±7.3 [mm] and height of ±12.2 [mm] with a 95% confidence level. For HBH, is has a depth sizing accuracy of ±0.2[mm], length sizing accuracy of ±5.4 [mm] and height of ±10.8 [mm] with a 95% confidence level. Table 3: Sizing accuracy for all (FBH and HBH) defects at 95% confidence level CASE STUDY The tool developed has been deployed over several proj- ects. One of these projects was for a European pipeline owner. PIPELINE CHARACTERISTICS A total of 226 anomalies were reported, of which 216 were classified as lamination. The remaining 10 anomalies are related to metal loss. All metal loss anomalies have been further analyzed, calculating Psafe and ERF (Emergency Repair Factor), based on ASME B31G. The results (POD and sizing accuracy) from the validation piece inspection, reflect the tool performance characteris- tics as described before in System Description BENEFITS OF THE LARGE DIAMETER PHASED ARRAY TOOL In previous inspections, labor intensive preparations were required to tune the system to the specific product prop- erties, which were not always known beforehand. This resulted in significant project complexity and cost, related to cleaning, drying, water supply, water treatment, etcetera. Due to the improved and flexible acoustic design of the Phased Array tool, this is not required anymore, because the acoustic properties of the tool can be calibrated and tuned to the specifics of the product in the pipe on-site. Safety, flexibility and reduced operational risk • • • • • For any pipeline of 20” ID and up, the system can be integrated in a single bidi body, similar to a cleaning pig. The system can be deployed as a bi-directional tool: a single access point can be used for deployment and retrieval. The small sensor head makes it possible to cope with tight bends, tees, reductions, etcetera. Simple, small pig launcher suffice. Phased Array technology increases flexibility to mul- titude of products and product types (heavy and light crude, diesel, naphtha, etc.) The pipeline had the following characteristics: • Optional availability of optical fiber for data commu- • Diameter: 28”; • Nominal wall thickness: 7.9; 9.5 and 12.7 mm; • • Operational product: Crude oil; • Inspection medium: Crude oil. Length: 110 meter; As a part of the Pig launcher, a validation spool is installed. The spool contains artificial metal-loss defects, with known dimensions. This allows additional performance, verifica- tion of system performance prior to the inspection, and to compare the tool performance historic results. RESULTS nication during the inspection run: the data can be re- viewed for position information and quality assurance: inspection parameters can be fine-tuned. Time efficiency • • Inspection in product is a significant time-saver for the out-of-service period of the pipeline. The tethered data collection allows for instant feed- back on the inspection quality, which allows for swift insight in the success of an inspection run. Cost effectiveness The inspection of the pipeline, covering a total length of 112 meters, was completed successfully in approximately 1.4 hours. The average velocity during inspection was 96 m/h. • Intero LDUT makes it economically feasible to even pig short and difficult to pig pipelines • Due to the capabilities of the tool to inspect in product, cost are reduced significantly.
RESEARCH / DEVELOPMENT / TECHNOLOGY PIPELINE TECHNOLOGY JOURNAL 17 The probability of detection and sizing accuracy has been validated, both by simulations and pull-tests. This has been confirmed on a real-life project. All metal losses, represented by FBH’s, were detected in all the runs. The a90/95 is established at 10.5mm for Hemi- spherical Bottom Holes. References Specifications and requirements for in-line inspection of pipelines - Version 2016 API Standard 1163, In-line Inspection Systems Qualification, Second edition, April 2013 Manual for Determining the Remaining Strength of Corroded Pipelines, B31G - 2012 Phased Array Ultrasonic Technology, 2th Edition, 2013, Eclipse Scientific, Authors Ries Augustijn Intero Integrity Services Manager Technology Center ries.augustijn@intero-integrity. com Environmental • No water usage, less cleaning, waste water (treatment), etc. Quality • Despite the fact that the inspection was executed in crude oil, the inspection performance on the validation spools was improved, compared to historic verification runs with a conventional tool in water. CONCLUSIONS A Large Diameter inspection tool has been developed based on the internal rotating mirror principle that allows the pipe to be investigated 360° degrees enabling to es- tablish both the measuring grid and beam profile according to the inspection requirements. The tool brings many benefits, robustness, flexibility (short-radius bends, offtakes) and versatility (product inde- pendency: any fluid). A tool with bi-directional capabilities in a cleaning-pig formfactor which can be deployed in a cost-effective manner for short and difficult to pig pipe- lines. Digital Transformation in the Pipeline Industry 30 June 2020, Online Knowledge Transfer Networking Competitive Technology Showcase www.pipeline-virtual.com
North Sea Wintershall Dea Case Study Christoph Seeber; Holger Hintelmann > NDT Global GmbH & Co. KG; Wintershall Dea AG Abstract Mittelplate is the largest oil field in Germany, located in the environmentally sensitive Wadden Sea of the German State Schleswig-Holstein. An artificial Drilling and Production Island, named “Mittelplate A” (MPA), was build early 1980`s on a tidal shoal and is operated by Wintershall Dea. In 2005, a 10 km, 10” stainless steel (1.4462 Duplex) pipeline was built in order to transport 2,500 tons of crude oil per day to onshore facilities. A second 10 km, 6” stainless steel pipeline (in parallel) is in place, returning the sepa- rated reservoir water to MPA in order to maintain the reservoir pressure. The pipeline made the transportation of oil via barge, which was dependent on tide and weather redundant. Both pipelines underpass the Wadden Sea, a highly vulnerable ecosystem, that has been placed on the UNESCO World Heritage list, over a distance of 7,2 km with a burial depth of 5 m to 25 m. In 2006, DEA and the NDT Global began conducting continuous monitoring of these pipelines. Ultrasonic inline inspections wall thickness robots are used to detect and size metal loss and mid-wall features in both pipelines. In addition, ultrasonic crack detection robots are used in the crude oil pipeline to detect and size axial flaws. Inspec- tions take place in 5 years intervals for the crude oil pipeline and 3 years intervals for the reservoir water pipeline. Regular inspections as mentioned above show a high degree of reproducibility over the years and hence facilitates comparison of the respective results. By this the operator is able to differentiate between manufacturing-related (non-hazardous) anomalies and potential hazardous material alterations. The results of those measurements, where no significant wear was detected, strengthen the confidence in the reli- ability of the used technology.
RESEARCH / DEVELOPMENT / TECHNOLOGY PIPELINE TECHNOLOGY JOURNAL 19 1. PIPELINE ASSET, FRAME CONDITIONS AND ENVIRONMENT 1.1 MITTELPLATE OILFIELD AND DRILLING / PRODUCTION PLATFORM (MPA) HISTORY The offshore installed artificial Drilling and Production Island Mittelplate (MPA) started production from five wells in 1987 producing the near centre vicinity of the field. The fluids were treated on MPA and then shipped of via barges to shore. To develop further areas the field, an advanced Field Dev. Concept was conducted. Besides the offshore operations from MPA, new production perspectives have been opened up by high-tech drilling technologies making it possible to reach the eastern section from shore by 2000. With these extended reach wells and a new build Onshore Treatment Plant located at Dieksand it was now possible to commercially produce this oil stream onshore. However, the relation between annual production and estimated reserves end up with a field life of more than 50 years, mainly due to the bottleneck of oil export from MPA to shore by barges. This bottleneck was mainly caused by the fact that the loading operation at MPA was limited by the available high tight time. Hence, the pipelines from MPA to Dieksand Facilities were build. Furthermore a new drilling rig, a Multiphase boosting sys- tem on MPA and the corresponding increase of the Diek- sand capacities were established, which made it possible to increase the production from MPA wells from 0,8 Mio t/a to 1,6 Mio t/a. Figure 2: Overview of the pipeline routing Figure 1: Overview of the geology and the development concept of the field 1.2 ENVIRONMENT: NATIONAL PARK, UN- ESCO WORLD HERITAGE When hydrocarbons are produced in environmentally sensitive areas such as the tidewaters of the eastern North Sea, a variety of additional challenges arise. MPA is located within these tidelands, that have been
20 PIPELINE TECHNOLOGY JOURNAL RESEARCH / DEVELOPMENT / TECHNOLOGY Figure 3: Overview of the Pipeline Laying Concept assigned as a National Park just after construction of MPA end of 1985. These National Parks stretching from Den- mark in the north to the Dutch waters in the south-west. Hence all activities must meet National Park Law, and State and Federal Nature Protection Acts. We have been producing oil trouble-free for more than 30 years, which is a good example of the proven expertise of Wintershall Dea. 1.3 PIPELINE CONSTRUCTION 1.3.1 INTRODUCTION / OVERVIEW In order to minimise the effects to the tidal shoals, the tem- perature influence caused by the warm media transported in the pipelines should be kept as low as possible. Further- more, a safe crossing, especially beneath the tidal creeks, needed to be ensured. As such, the pipeline was laid at a depth of approx. 20 m using HDD drilling. the pontoons platforms at the corresponding construction pit by means of winches. 1.3.2 PIPELINE BASE DESIGN AND OP- ERATIONS CONSIDERATIONS For several reasons, the overall plant capacity on MPA cannot be substantially expanded. Therefore the existing facilities are being used to separate water from the oil and the pre-treated wet oil is then being transported to the Dieksand Facilities via the oil pipeline, where the oil is further processed to meet the required specifications. The oil pipeline was thus designed for multiphase flow of 4900 t oil/d with additional up to 20% water and up to 60,000 m³ natural gas/d. For the detailed design engi- neering, simulations using the multiphase flow program “OLGA 2000” were carried out at the Institute of Process Engineering of the University of Hanover. The reservoir water separated in Dieksand is returned to MPA via a water pipeline and injected into the reservoir. For this, 6 pipeline segments (spools) were prefabricated onshore and connected to each other by welding in 6 con- struction pits at a depth of approx. 5 m. 1.3.3 PIPELINES MATERIAL SELEC- TION AND WELDING PROCESS On each pit, made of sheet pile, a combination of 2 pon- toons was arranged on either side. The two pontoons were connected by a platform supporting a HDD drilling device. From each platform 2 horizontal boreholes were drilled, into which the oil pipeline and the reservoir water pipeline were pulled. The majority of the pipe, approx. 1.4 km sections, were pre-fabricated on land and laid out on the prefabrication site. For the transport of the pipe sections to the construc- tion pits, a transport route was constructed in the mudflats roller conveyors. The pipe sections were then pulled onto Considering its location, where conventional maintenance is hardly possible, considerable efforts have been under- taken to assure proper design, material selection, prefab- rication and welding connection of the prefabricated pipe sections as well as enhanced operational control. Due to the intended wet oil transport (max. 60 °C and max. 100 bar) with a CO2 content of the associated gas of up to 2 mol% and the high total salt content of the associated water of 230 g/l it was necessary to manufacture the pipe- line from stainless steel.
LEADERS IN CORROSION PREVENTION & SEALING TECHNOLOGY PREMIER COATINGS LTD Headcorn Road, Smarden Ashford, Kent TN27 8PJ UNITED KINGDOM TEL: +44 (0) 1233 770 663 www.premiercoatings.com A MEMBER OF WINN & COALES INTERNATIONAL
22 PIPELINE TECHNOLOGY JOURNAL RESEARCH / DEVELOPMENT / TECHNOLOGY In view of the long-term resistance required above and based on good practical experience with duplex steel (22 % chromium and other transition metals) in German and international oilfield applications, this extremely corro- sion-resistant material was selected.Although Duplex is highly resistant towards CO2, in the presence of hydrogen sulphide pitting corrosion can occur, which can possibly initiate sulphide stress corrosion cracking. Therefore, the hydrogen sulphide content of Mittelplate oil gas is periodi- cally examined to avoid critical H2S ranges. The individual 18m pipe spools were connected at the pre- fabrication site using arc welding, whereby each weld seam was NDT inspected by means of radiography. Additionally a camera inspection from the inside took place to ensure that there were no temper colors visible. The connection of the prefabricated pipeline sections in the area of the HDD construction pits was carried out using short bends and the extremely corrosion-resistant Hastelloy steel. 1.4 PIPELINE SAFETY SYSTEMS Although highly unlikely, an optical fiber cable, using temperature measurement method, laid in parallel to the pipelines is being used to detect any leaks. Cathodic corrosion protection was installed as well to pro- tect the pipeline from external corrosion in case of damage to the outer coating. However, since both pipelines can be cathodically polarized without any problems, it can be assumed that the pipelines have not been damaged during transport or installation. As mentioned in the above, the pipeline material was se- lected in such a way that internal corrosion can practically be excluded. All welding seams were tested and integrity of the outer coating after pulling in was confirmed. However, in order to ensure the greatest possible safety of the pipeline, an additional program for intelligent pigging of both pipelines is being conducted. 2.0 IN-LINE INSPECTION TECH- NOLOGY AND ROBOTS 2.1 ULTRASONIC WALL THICKNESS INSPECTION Objective of ultrasonic wall thickness measurement in pipelines is the detection of metal loss such as corrosion anomalies in order to prevent leakages with possibly cata- strophic consequences. The measuring principle is based on perpendicular incidence of ultrasound into the pipe wall. The ultrasonic pulse is reflected from the back wall and travels several times back and forth, until the signal energy is dissipated. The received signal is a sequence of rear wall echoes. The time between entry echo and first rear wall echo or between two rear wall echoes is measured. In addition, the distance between probe and pipe wall is mea- sured (stand-off). Due to the known sound velocity in the medium, the stand-off can be directly calculated from the time-of-flight of the entry echo. The stand-off information allows a distinction between internal and external metal loss, since the stand-off signal changes only if an internal metal loss is present. With internal metal loss, the stand- off information behaves reciprocally to the wall thickness information. Apart from internal and external metal loss, this method allows to detect other types of anomalies such as laminations, inclusions and deposit or surface inhomo- geneities, since the ultrasonic signal is also reflected from various inhomogeneities at or within the pipe wall. The robots used include LineExplorer UM, UMh, UMp and Evo 1.0 UMp robots which basically function in the same way but provide increasing circumferential and axial reso- lutions over the evaluation period. All of them have a depth sizing accuracy of ± 0.4 mm. The schedule of ultrasonic wall thickness inspections is shown in Table 1 Table 1: Ultrasonic wall thickness inspections, 10” crude oil pipeline
RESEARCH / DEVELOPMENT / TECHNOLOGY PIPELINE TECHNOLOGY JOURNAL 23 2.2 ULTRASONIC CRACK INSPECTION Objective of the ultrasonic crack inspection in pipelines is the detection of crack-like anomalies in order to avoid pipeline failures caused by cracks. The principle of the ultrasonic crack inspection is based on the 45° angle beam technique using transverse waves. Due to the so-called corner reflection, even minor cracks from approx. 1 mm onwards give quite strong reflections. The pulse echo technique is applied, i.e. the same probe serves both as transmitter and as receiver; then the signals undergo further processing. The following figure shows the measuring principle and a schematic representation of the measuring signal (A-scan). The position of the anomaly (external, internal) can reliably be determined from the distance between the entry echo and the anomaly echo. For inline inspection, the coupling of the ultrasonic pulses into the pipe wall is achieved through the pipeline medi- um. Due to the different sound velocities in the coupling medium and in steel, an angle of incidence of approx. 17° is required in order to obtain a refraction angle of approx. 45° in the pipe wall. Crack-like anomalies will be recorded if their amplitude exceeds a pre-defined threshold and if the anomaly is present over a pre-defined minimum length (typically 30 mm). The robots used include LineExplorer UC and Evo 1.0 UC robots. The major technological improvements are switch from use of depth classes to absolute depth sizing within LineExplorer UC and improved signal processing for higher inspection velocities with Evo 1.0 UC. The schedule of ultra- sonic crack inspections is shown in Table 2. 3 IN-LINE INSPECTION RESULTS 3.1 ULTRASONIC WALL THICKNESS INSPECTION All of the reported anomalies were identified either as grindings or as irregularities from the mill process (manu- facturing-related metal loss). This was standing to reason as the presence of corrosion was unlikely at that early stage and due to the pipe material used. The anomalies were located at girth welds which is a typical location for manufacturing-related metal loss, and the random cir- cumferential distribution of metal loss anomalies is an additional hint for manufacturing-related origin, whereas corrosion typically (but not necessarily) concentrates at a certain circumferential position, mostly at the bottom of the pipeline. The majority of the anomalies detected in the 10” crude oil pipeline was actually below the reporting threshold of 1.0 mm. The deepest metal loss anomaly had a depth of 2.2 mm (20 %) and a remaining wall thickness of 8.6 mm. The anom- aly is located at the Mittelplate launcher site, whereas the major part of the anomalies was detected within the onshore part of the pipeline between km 9 and the Diek- sand receiver site. An increase of reported anomalies can be observed from 2006 to 2019 (Figure 4). Nevertheless, a major increase of metal loss depths cannot be identified. For the main part, anomalies close or even below reporting threshold were added. On the other hand some indications close to the receiver site were dismissed. e.g. if identified as parts of wall thickness variations. The ones classified with ambiguous location in wall initially could be iden- tified as either internal or external during the following inspections. Better data resolution led both to more exact determination of location in wall and detection of addi- tional anomalies. After the last inspection carried out in 2019, a total of 35 anomalies was reported of which 9 were classified as external and 26 were classified as internal. The anomaly with the greatest depth measured in 2019 is the same as the one with the greatest depth measured in the initial inspection with the difference that the measured depth in 2019 is 1.9 mm and therefore lower than in 2006 (2.2 mm). This difference is well within the depth sizing tolerance of 0.4 mm that has to be taken into account for each measurement. 3.1.1 10” CRUDE OIL PIPELINE, MITTELPLATE - DIEKSAND 3.1.2 6” RESERVOIR WATER PIPE- LINE , DIEKSAND - MITTELPLATE The first inspection in the 10” crude oil pipeline in 2006 from the Mittelplate launcher site to the Dieksand receiv- er site revealed 15 metal loss anomalies, of which 2 were classified as internal and 13 were classified with ambiguous location in wall. For the ones classified with ambiguous location in wall, the radial position could not be clearly determined initially. All of those anomalies were located at welds which caused sensor carrier lift-off so that it could not be clearly determined whether the stand-off indication is a result from sensor carrier lift-off or from internal metal loss. In the 6” reservoir water pipeline, the number of detected metal loss anomalies in the first inspection in 2007 was 160 (140 external, 14 internal, 6 with ambiguous location in wall). Only 5 metal loss anomalies were clearly identified as grindings, further classification of the remaining metal loss anomalies was left open with a remark in the inspection report that they are most likely manufacturing-related. The greatest measured depth was 2.6 mm / 19 % (remain- ing wall thickness 13.4 mm) for an internal metal loss
24 PIPELINE TECHNOLOGY JOURNAL RESEARCH / DEVELOPMENT / TECHNOLOGY Table 2: Ultrasonic crack inspections, 6” reservoir water pipeline Figure 4: Circumferential distribution of metal loss, 10” crude oil pipeline, 2006 (left) and 2019 (right) Figure 5: Circumferential distribution of metal loss, 6” reservoir water pipeline, 2007 (left) and 2019 (right) anomaly. In the 6” reservoir water pipeline, the majority of the reported anomalies had depths between 1.0 and < 2.0 mm. Also here, the circumferential distribution of the metal loss anomalies does not show a concentration of at a particular circumferential position which also indicates that corrosion as origin of those metal loss anomalies is unlikely. The inspection results over the observed period show a noticeable increase of reported anomalies (Figure 5). Nevertheless, as observed in the 10” crude oil pipeline, there is no increase in overall depth. In the majority, shal- low anomalies were added over the years, many of them below reporting threshold. The deepest anomaly identified in 2007 was sized with the same depth of 2.6 mm in the 2019 inspection. The deepest anomaly reported in 2019 (2.8 mm) shows a an increase in depth versus 2007 by 0.4 mm which is within sizing tolerance and does not indicate growth.
RESEARCH / DEVELOPMENT / TECHNOLOGY PIPELINE TECHNOLOGY JOURNAL 25 3.2 ULTRASONIC CRACK INSPECTION RESULTS Ultrasonic crack inspections were solely carried out in the 10” crude oil pipeline. The first inspection in 2006 revealed 4 crack-like, 139 notch-like and 5 inclusion-like anomalies. The crack-like anomalies were considered to be most likely manufacturing-related anomalies such as mill anomalies. All of the crack-like anomalies were classified with depth < 1.0 mm. In 2009, 5 crack-like anomalies and 206 notch- like anomalies were detected. Except of one of the 5 crack- like anomalies, 4 were reported in 2006. The one which was not reported in 2006 could be identified subsequently in the inspection data whereas the length and the ampli- tudes were below reporting threshold. Of the 206 notch- like anomalies, 201 were classified with depth < 1.0 mm and 5 with depths between 1.0 and 2.0 mm. The UC inspection run in 2014 was the first UC run in this pipeline with absolute depth measurement. The previous inspection runs only allowed for classification of axial anomalies into depth classes. Furthermore, a more detailed classification was applied. In 2014, only one anomaly was classified as crack-like. Moreover, 15 anomalies were clas- sified as mill anomalies, 23 as notch-like, and 10 as weld anomalies. For all reported anomalies, depths below 1.0 mm were reported. The remaining crack-like anomaly was considered to be a manufacturing-related weld anoma- ly.15 anomalies clearly identified as weld anomalies were considered to be inhomogeneities of long seam welds such as edges from misalignments which were not grind- ed. The run comparison carried out between the 2019 and the 2014 surveys revealed a further decrease of reported anomalies from 49 to 28. 24 of these anomalies could be related to anomalies reported in 2014. 4 newly reported weld anomalies reported in 2019 could be identified in the 2014 inspection data subsequently, so that a new forma- tion of these anomalies could be excluded. There were 25 anomalies from the 2014 survey which were not reported in 2019. For all of those, the reported depth ranged below 0.6 mm which is below feature specification and was therefore omitted. 22 of those anomalies show according indica- tions in the 2014 inspection data which were identified as surface- and weld inhomogeneities and therefore not reported. 3 anomalies classified as notch-like with depth of 0.2 mm in 2014 were classified as irrelevant during the analysis of the 2019 inspection data. 4. COMPARISON OF WALL THICK- NESS INSPECTION RUNS 4.1 OBJECTIVE AND METHOD growth, the depth difference of corresponding metal loss anomalies is analyzed. Based on the depth sizing accu- racy of ±0.4 mm (90 % confidence level), the comparison tolerance for the depth difference of a single anomaly is ±0.6 mm. This means that the measured depth difference is expected to be within ±0.6 mm with a probability of 90 %, provided that the anomaly did not grow between the compared inspections. Considering a total of N anomalies, the comparison tolerance for the average depth difference of N features is ±0.6 mm / √N. manufacturing-related are considered to be static anoma- lies where corrosion growth is not expected. Those anom- alies are compared separately in order to verify reproduc- ibility and accuracy of the depth-/ remaining wall thickness measurement of the robots used, and to confirm the manufacturing-related origin of the anomalies. Comparison of ultrasonic crack inspections is carried out similar to comparison of wall thickness inspection run comparison in terms of feature and signal identification and correlation between two runs. Compared to the ap- proach used in comparison of metal loss anomalies which is more quantitative and statistical has its focus on the en- tity of observed features, the comparison of axial anoma- lies rather uses a qualitative and anomaly-based approach. 4.2 WALL THICKNESS RUN COMPARISON IN 10” CRUDE OIL PIPELINE, MITTELPLATE - DIEK- SAND THE FIRST WALL THICKNESS RUN The first wall thickness run comparison carried out on the 10” crude oil pipeline on the runs from 2006 and 2009 identified 14 of 40 metal loss anomalies reported in 2009 which had corresponding features in the 2006 inspection. This means that there were 26 newly reported anomalies without corresponding reported anomalies in 2006. The subsequent analysis of the corresponding locations in the inspection data from 2006 revealed that those anomalies only appeared as minor irrelevant indications in the first inspections. The sensors used in 2009 delivered a better data visualization at such locations which allowed iden- tification and sizing of these metal loss. Therefore, the increased number of metal loss anomalies does not nec- essarily mean new emergence of metal loss. From the 14 anomalies that could be correlated, the depth differences range between -0.3 mm and +0.2 mm, the mean difference is 0.0 mm. Therefore, corrosion growth is not indicated. In the comparison between 2009 and 2014, all of the 34 metal loss anomalies reported in 2014 had corresponding reported anomalies in 2009. The depth differences range between -0.7 and +0.4 mm, the mean value is -0.07 mm. Wall thickness inspection run comparisons are carried out in order to identify and quantify growth of metal loss anomalies. To assess the likelihood of potential corrosion Between 2014 and 2019, 34 of 35 metal loss anomalies reported in 2019 could be related to anomalies reported
26 PIPELINE TECHNOLOGY JOURNAL RESEARCH / DEVELOPMENT / TECHNOLOGY in 2014. One metal loss anomaly could be identified and sized subsequently in the 2014 inspection data. The differ- ences of the remaining wall thickness range between -0.5 and +0.4 mm, the mean difference is -0.083 mm which is within the comparison tolerance of 0.096 mm. 5. WALL THICKNESS RUN COMPARI- SON IN 6” RESERVOIR WATER PIPE- LINE, DIEKSAND - MITTELPLATE The run comparison between 2007 and 2010 revealed an increase of reported metal loss. There were 45 features that had no corresponding reported anomaly in 2007. The depth of 29 of these features was actually below the reporting criteria. 44 of these newly reported features were classified as manufacturing-related. All locations of newly reported anomalies within reporting criteria were checked in the 2007 data where corresponding indications could be identified for each call. For the 23 metal loss anomalies that were not classified as manufacturing-related, a corrosion growth analysis was carried out. The mean change of remaining wall thickness was -0.04 mm which is within the comparison tolerance of 0.125 mm. A statistically relevant indication of corrosion growth is therefore not present and the observed anoma- lies can therefore be considered manufacturing-related. A further significant increase of 184 reported metal loss anomalies was observed in the comparison between 2010 and 2013. 182 of these anomalies were classified as manufacturing-related, 115 had a measured depth ≤ 1.0 mm. 84 of the newly reported anomalies had corresponding indications in the 2010 inspection run. The depth differ- ences between newly reported features and corresponding indications in the 2010 run are within the measurement accuracy of ± 0.4 mm. Also here, corrosion growth could be excluded in all probability. In the comparisons between 2013/2016 and 2016/2019, just a minor increase of reported anomalies was recog- nized. Likewise, no statistically significant indication of corrosion growth could be proven for these run compari- sons. 6. CONCLUSION It is undisputable that the drilling platform Mittelplate and the pipeline assets being located in the tidal flats of the Wadden Sea require maximum possible efforts in safe construction and operation in order to minimize any impact on this valuable and vulnerable environment. The ILI surveys carried out in both pipelines showed that there is no hazard emanating from corrosion or axial anomalies that could form leakages. With respect of metal loss, the run comparisons revealed that statistically relevant growth cannot be attested. Initial classification as manufacturing-related or at least the initial assumption that metal loss anomalies are of manufacturing-related origin have been confirmed repeatedly during this long observation without proven growth. The history of ultrason- ic crack inspections shows a larger variety of classified and reported anomalies, whereas a serious threat was never identified. The results over the entire observation period vividly reflect the increase of technological capabilities in terms of sizing from the use of depth classes up to applica- tion of absolute depth sizing, where the results of absolute depth sizing confirm the previous depth classes of report- ed anomalies. The classification of anomalies over the observation period shows a trend towards non-hazardous anomaly types and less reported anomalies. This is most certainly a consequence of technological improvement in terms of resolution and sizing capabilities, increasing anal- ysis experience, and possibly a more conservative classifi- cation during the initial inspection that could gradually be amended from survey to survey. Overall, it’s well proven that there is no degradation of the condition of the pipelines over the entire period of operation since being in service. Due to the extraordinary situation that all ILI surveys have been carried out by the same contractor with consistent robot technology apart from gradual development, a high degree of comparability of the results is given, underpinning the reliability of the single inspection results. Authors Christoph Seeber NDT Global GmbH & Co. KG Project Leader UM christoph.seeber@ndt-global. com Holger Hintelmann Wintershall Dea AG General Manager Upstream Facilities holger.hintelmann@ wintershalldea.com
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Quantitative Pipeline Risk Assessment (QPiRATM) Fire and Dispersion Analysis of a Subsea Gas Pipeline Leak Using Empirical Consequence Modelling M Nazmi B M Ali Napiah, Shaikh Abdullah B Shaikh Othman, Aishah Mastura Supian > PETRONAS, Malaysia Abstract A subsea pipeline transporting gas in Malaysia has a small leak at its subsea flange at 70m water depth, located 140m away from the processing platform. The flange has undergone three rectification works; however, the repair works were unsuccessful to achieve zero leak. A Quantitative Pipeline Risk Assessment (QPiRATM) fire and disper- sion analysis has been conducted to analyze the potential hazards from the leak to assets and environment and the consequence of the release to human safety. The result from this study can be used by the operator to manage risk by introducing a modification to the operation procedure or applying a mitigation measure, if required. A process hazard analysis software, PHAST 6.7 has been utilized to perform fire and dispersion study for the iden- tified leak flow. This paper will present the method of conducting the study by establishing the leak size from the given flow rate, calculating the subsea and sea surface release rates, and performing sensitivity analyses for different leak cases should the leak flow rate increases over the operation time. The concentration of the gas release from the current leak size to the environment is calculated for the potential of fire and explosion and its possibility of human fatality within the heat radiation zone.
1. INTRODUCTION 1.1 SUMMARY An 18inch subsea pipeline transporting gas in Malaysia has a small leak at its subsea tiein flange at 70m water depth, located 140m from the processing platform. The leak loca- tion was rectified previously by installing the encapsulated clamp to contain the leak. An 18inch subsea pipeline transporting gas in Malaysia has a small leak at its subsea tiein flange at 70m water depth, located 140m from the processing platform. The leak loca- tion was rectified previously by installing the encapsulated clamp to contain the leak. The amount of gas leak in terms of production loss was studied and a Quantitative Pipeline Risk Assessment (QPiRATM) fire and dispersion analysis has been conduct- ed to analyze the potential hazards from the pipeline leak in terms of fire and dispersion. The result of the study is used to establish the risk level to continue operating the pipeline and to manage the risk by introducing a modifi- cation to the operation procedure or applying a mitigation measure, if required. 2. METHODOLOGY FOR SUBSEA FIRE AND LEAK DISPERSION STUDY PETRONAS has adopted the DNV Consequence Modelling software to conduct the leak and fire dispersion study for this case. The overall study approach is represented in Figure 1. RESEARCH / DEVELOPMENT / TECHNOLOGY PIPELINE TECHNOLOGY JOURNAL 29 For data gathering, a study to quantify the leak rate and volume was conducted by measuring the bubbles leakage from the flange. ROV inspection recorded the bubbles formation, where the diameter and no of bubbles were measured to generate the total product loss per day. The meteorological data for the environment at the platform was also gathered to establish the wind condition for the dispersion analysis. 2.1 DATA GATHERING Details of the pipeline data are: Table 1: Pipeline Data 2.1.1 FLUID COMPOSITIONAL DATA The fluid composition is obtained and the gas comprises of 90% methane and 6% ethane. This data is used as input into PHAST 6.7 to calculate for the Lower Flammability Limit (LFL) and Upper Flammability Limit (UFL) of the product. 2.1.2 METEOROLOGICAL DATA The meteorological for environmental condition was ex- tracted for the analysis: Figure 1: Methodology Flow Chart The above mentioned wind condition have been selected based on the wind rose data and the suggested Pasquill Table 2: Environmental Data
30 PIPELINE TECHNOLOGY JOURNAL RESEARCH / DEVELOPMENT / TECHNOLOGY Table 3: Meteorological Conditions Defining Pasquill Stability Classes Table 4: Stability Classes Description Table 5: Flange Leak Data
Stability Class given in the PTS 16.71.05 Physical Effects Modelling. These are shown in tables 3 and 4 on the left. 2.1.3 FLANGE LEAK DATA The gas leak from the flange were studied and analyzed from ROV inspection video frame by frame. The maximum bubble diameter of leakage was calculated for the image frames and taken as a conservative value. The total volume of gas leaked per year (mmscf/yr) is quantified as 0.115 mmscf/yr. Figure 2: Release of bubbles from the encapsulated clamp The flange leak data was quantified and calculated as per Table 5 on the left. 2.2 FIRE AND DISPERSION MODELLING STUDIES The dispersion modelling was performed using the DNV GL consequence modelling software package PHAST 6.7. RESEARCH / DEVELOPMENT / TECHNOLOGY PIPELINE TECHNOLOGY JOURNAL 31 PHAST is DNV GL’s propriety software for consequence modelling which has been used by the oil and gas industry for more than 20 years. The PHAST package simulates the release of material from its process conditions in a vessel or pipe, through all the stages in this dispersion to a concentration. Once the leak rate from the flange was quantified, the pipeline was modelled in PHAST 6.7 to simulate the cor- responding leak size that would generate the leak rate of 0.000112kg/s at current operating condition of 100bar and 28°C. Using the subsea leak size obtained from this model, the release rate on the sea surface will be calculated using formula from Ref 4 Scandpower – Handbook for Fire Calcu- lations and Fire Risk Assessment in the Process Industry: Where Mog = initial gas leak rate (kg/s) A = release area (m2) Cd = coefficient of discharge γ = cp/cv, gas specific heat ratio cp = specific heat of vapor, constant pressure (J/kg°C) cv = specific heat of vapour, constant volume (J/kg°C) p2 = pressure inside containment (N/m2) T = temperature in containment (K) R = gas constant = 8,314 (kgm2/Kmols2) M = molecular weight (kg/mol) The pool diameter was then calculated using formula from Ref 3 UK HSE Dispersion of Subsea Releases – Review of Prediction Methodologies. The sea surface release rate and pool diameter were then used as input in PHAST 6.7 to determine the release gas concentration on the sea surface and the resulting flam- mable gas dispersion. This was carried out using the “User Defined Model” within PHAST 6.7. According to Chemical Process Quantitative Risk Assess- ment (CPQRA) Guideline by Center of Chemical Process Safety (CCPS), the basis of specification of 50% LFL is to allow for variations in instantaneous cloud concentra- tions. The energy available in flammable cloud is based on the average concentration, so the average value is the appropriate criterion for the estimation of the vapor cloud explosion impact. Although conservative, for an instanta- neous release, a large fraction of the total amount can be in the explosive region, irrespective of source strength and meteorological conditions.
32 PIPELINE TECHNOLOGY JOURNAL RESEARCH / DEVELOPMENT / TECHNOLOGY Figure 3: PETRONAS Risk Acceptance Framework 2.3 RISK ASSESSMENT For this assessment, PETRONAS Risk Acceptance Frame- work has been adopted. The risk level shall be represented as the Individual Risk per Annum (IRPA) and this shall comply with PETRONAS Risk Acceptance Framework where the maximum tolerable limit of the ALARP region is 1E-03 per year to workers including contractors. The Individual Risk Per Annum (IRPA) is calculated using the formula:
RESEARCH / DEVELOPMENT / TECHNOLOGY PIPELINE TECHNOLOGY JOURNAL 33 Table 6: Gas Dispersion Result 3 RESULTS Based on the consequence results from PHAST 6.7, the current subsea flange leak at 100bar operating pressure with the release rate of 0.000112kg/s is not anticipated to result in any flammable hazards due to very low center- line flammable concentration. The centerline flammable concentration is below 1000ppm, which is only 2.4% when compared to the LFL concentration of 42083ppm. No dispersion can be seen from PHAST 6.7, and this could be attributed to the small release rate and high water depth of 73m at the leaked flange. Since there is no flammable hazards to give rise to LFL plume and subsequent fire/ explosion, no casualty risk hence is expected. Several sensitivities studies were conducted by varying the leak size and release rate to determine the limit when the concentration will reach 0.5LFL at the centerline. Figure 4: Gas Dispersion Table 7: Leak sizes and release rates
34 PIPELINE TECHNOLOGY JOURNAL RESEARCH / DEVELOPMENT / TECHNOLOGY 4. CONCLUSIONS From the case studies conducted, it was concluded that: • Using software PHAST 6.7, the amount of gas release (1.12E-4kg/s) from leaked flange has a very low flam- mable concentration (<1000ppm). This is very much below the Lower Flammable Limit (LFL) thus not antic- ipated to produce fire given a source of ignition. There is no consequence to cause fatality for this leak rate as there is no fire due to very low concentration. The total risk for the leaked flanged with leak rate of 1.12E-4kg/s is perceived to be within the ALARP region, hence no immediate intervention is required on the flange. Based on the study, the subsea release rate of 8.96kg/s equivalent to 25mm of leak/hole size would yield 0.5LFL concentration at the centerline on the sea surface level. Flammable plume in this case could possibly be ignited resulting in fire. • • Authors M Nazmi B M Ali Napiah PETRONAS, Malaysia Custodian (Pipeline Integrity)/ Group Technical Authority firstname.lastname@example.org Shaikh Abdullah B Shaikh Othman PETRONAS, Malaysia Principal Engineer email@example.com References 1. 2. 3. 4. 5. PTS 16.71.04 Quantitative Risk Assessment (QRA), 2014, PETRONAS Technical Standard PTS 16.71.05 Physical Effects Modelling, 2014, PETRONAS Technical Standard (PTS) Dispersion of Subsea Release – Review of Prediction Methodologies, 1995, UK HSE Offshore Technical Report Handbook for Fire Calculations and Fire Risk Assessment in the Process Industry, Scandpower Risk Management AS  OGP Risk Assessment Data Directory, March 2010 Aishah Mastura Supian, PETRONAS, Malaysia Pipeline Engineer firstname.lastname@example.org. my COMPLEMENTARY SERVICES FOR YOUR CORPORATE-COMMUNICATION Pipeline Technology Journal Offers multiple advertising opportunities to increase your company‘s visibility e-Journal Technical Articles e-Newsletter Latest News Website Information Hub IN OUR MEDIA KIT FOR 2020 YOU FIND ALL DETAILS ABOUT OFFERS, PRICES, TOPICS AND DATES
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OMEGA Fiber Optic Monitoring System: New Features for Technological Security of Transneft Pipelines Dr.Aleksey I.Turbin > OMEGA Abstract Since 2009 the OMEGA Company develops and produces multifunctional monitoring systems for extended facili- ties indicating in online mode oil, oil products and gas leaks as far as third party activity in the protected zone using a fiberoptic cable (FOC) as sensing element. Implementing distributed acoustic and temperature sensors the Leak Detection and Activity Control System (OMEGA LDACS) provides precise detection of location and nature of vibra- tions and change of temperature characteristics on and around extended facilities. The leaks are detected through analysis of fluctuations both in the temperature and vibroacoustic field. Having equipped more than 6000 km of pipelines with OMEGA LDACS in Russia and abroad the Company is in permanent search of ways of improvement of the FOC monitoring technologies. The newest LDACS feature is the implication of the artificial neural network for more precise identification of potentially dangerous events registered by the system. Another option in the equipment of LDACS with additional pressure and displacement sensors.
RESEARCH / DEVELOPMENT / TECHNOLOGY PIPELINE TECHNOLOGY JOURNAL 37 Figure 1: The OMEGA System Design The main feature to be developed in coming years in the implementation in OMEGA LDACS of artificial neural networks for better recognition of events registered by the system. Having been founded in 2009 the OMEGA Company celebrated its first anniversary last year being one of the European leaders in total monitoring system equipment length which reached 6000 km last year. The fifth version of the OMEGA LDACS based on tem- perature and acoustic field monitoring and implemented now on TRANSNEFT pipelines provides high-precision detection of location and nature of acoustic vibrations and temperature characteristics of pipelines. The extended object is monitored through the whole length of optic fiber used for the System`s sensor and not requir- ing electric power along the line in real time mode. In comparison to similar systems the OMEGA LDACS shows high accuracy (≤3m) both event detection on ex- tended object. The main achievement of the OMEGA scien- tific team is the implementation of artificial neural network for more precise recognition of the potentially dangerous event. The range of parameters that can be measured by fiber optic sensors is quite extensive. These are the tempera- ture and temperature change dynamics, absolute and gauge pressure, linear-and-angular movements and the rate of speeding up. The use of high-stable materials and application of cutting-edge technologies make it possible to produce ultra-high accuracy sensors. These are main directions of product development for OMEGA scientists – keeping an eye on other implication fields besides oil and gas transportation. With high sensitivity rate the OMEGA LDACS can be ap- plied for detection of pipeline ruptures or small leakages amounting to hundreds of liters per 5 minutes. The fluid flowing under high pressure generates the acoustic wave detected by optic cable. With false alarms being the main universally recognized disadvantage of FO technologies the implementation of the mentioned version 5 of OMEGA LDACS on one of the 200 km pipelines in middle Russia allowed the reduce the false alarms rate by 6 times bringing it to the acceptable 2-5% level. The general ideology of the system of event recognition based on artificial intelligence is the creation of patterns describing the reaction of both DAS and DTS sensors to leaks and other events. The absence of some acoustic and temperature parameters which the system needed some years ago for a concrete event alarm is replenished by the “experience” of OMEGA LDACS – which is in fact the cen- terpiece of the artificial intelligence. In general, the OMEGA LDACS is build around two crucial
38 PIPELINE TECHNOLOGY JOURNAL RESEARCH / DEVELOPMENT / TECHNOLOGY In general, the OMEGA LDACS is build around two crucial sensors developed and patented by our scientific groups. GA LM to record hundreds of events simultaneously. Another direction of OMEGA Company research and The OMEGA DTS based on the of Raman light scattering analyzes changes in the temperature field and detects in real-time mode leaks of gas, oil and other liquids in single- and multiphase pipelines. Table 1: OMEGA DTS parameters The OMEGA DAS architecture is based on the use of fiber optic cable as a set of virtual microphones and as a means of information transmitting. DAS uses coherent optical reflectometry (COTDR) to analyze backscattered light to record vibrations in several virtual channels, the number of them can reach tens of thousands. This enables the OME- Table 2: OMEGA DAS parameters development is the elaboration of compact and cheaper solutions demanded for other branches besides oil and gas transportation. An important step on this way is done this year– in Riga, Latvia, we begin tests of our Heating Systems Monitoring system based on same principles as our LDACS. It seems to be a promising business sector for OMEGA Company – the implementation of pour achieve- ments in this branch can help avoid hot water transporta- tion cuts and both economic and environmental damage. Figure 2: Reflectograms of several impacts registered before recognition
RESEARCH / DEVELOPMENT / TECHNOLOGY PIPELINE TECHNOLOGY JOURNAL 39 Figure 3: The OMEGA Pig Detection Function Using competences accumulated by our divisions we offer our services in IT-research & development in oil and gas sector, first of with implementation of artificial neural net- works. Our scope comprises Fiber Optic lines design and construction as far as technical and financial consulting in facilities construction in energy and fuel production and transportation. Table 3: OMEGA LDACS technical parameters A permanent focus on market requirements will hopefully help the OMEGA Company to diversify its production. The latest development is the requisition of the partnership status of Russian divisions of such companies as HUAWEI and LENOVO – we see this as a kind of recognition of the level achieved by OMEGA Company engineers. OMEGA LDACS main equipped facilities (state – April 2020): • “Baltic Pipeline System (BPS-2)”, equipped length - 1000 kilometers“ “East Siberia – Pacific Ocean“ Pipeline System”, “Skov- orodino – Koz’mino” sector, equipped length - 2500 kilometers“ “Pur-Pe – Samotlor” Pipeline System, equipped length - 429 kilometers • • • Adamtash- Dzharkuduk and Dzharkuduk - Shurtan- neftegaz Commodity Park condensate pipeline (LU- KOIL Uzbekistan Operating Company) – 150 km. With the international market of FO monitoring systems satiated in recent years by both internationally recognized and national producers the OMEGA Company concen- trates its efforts of a broader range of business directions contiguous to what we have done in last ten years. Author Dr.Aleksey I.Turbin OMEGA Company Advisor to Director General firstname.lastname@example.org
Enhancing Energy Efficiency and Reducing Greenhouse Gas Emissions through Innovation and Renewables Integration Ernesto Nasini, Marco Santini, Marco Baldini, Simone Amidei, Maurizio Vaccaro > Baker Hughes Abstract Consequences of global warming on Earth’s climate are one of the greatest challenges worldwide faced, particu- larly by industry players. To effectively reduce the amount of greenhouse gas emissions, it is necessary to increase efficiency and exploit renewable energy sources. Baker Hughes (BH) developed technologies to reduce CO2 emissions and benefit from integration with renewables, such as pipeline compression stations and LNG plants, leading up to 55,000 tons/year of CO2 emission savings and up to 20,000 tons/year of fuel gas savings for a PGT25 turbo-compressor train. Paper introduces an innovative technology to convert heat into electricity: the system, a Brayton closed-cycle, is suitable for low power applications ranging between 0.5MWe and 1.0MWe. This patent-pending technology uses CO2 as working fluid and is based on a reciprocating expander-compressor becoming a competitive alternative, in terms of safety and total cost of ownership, to other WHR solutions. As addi- tional benefit, typical application for this small system is for remote areas where electricity grid is either not present or unreliable. Besides power generation, waste heat can be utilized for refrigeration, down -5°C ÷ - 18°C, using hydrocarbons or CO2 as working fluid. This cold duty can chill process gas saving compression energy or can be used for different chilling purposes. This patent-pending system is composed by an Organic Rankine Cycle combined with a refrig- eration cycle utilizing the same working fluid, both services being directly coupled in simplified architecture fully sealed with magnetic bearings. Additionally, BH patented Hybrid Gas Turbine solution to integrate mechanical drive gas turbines with variable frequency drive electrical machine. A dedicated software optimizes customer needs to minimize CO2 emissions, fuel savings and energy storage, considering the availability of electric energy also from renewable sources. This configuration allows to stabilize the exhaust thermal load for the WHR system independently from the compressor process conditions.
RESEARCH / DEVELOPMENT / TECHNOLOGY PIPELINE TECHNOLOGY JOURNAL 41 1. INTRODUCTION There are several solutions to reduce emissions of green- house gases in the pipeline environment: renewables, effi- ciency & innovative technologies, including energy storage, developed by BH, can be viably and affordably applied to operator plants. the crankshaft vs. 10000rpm and above for rotors) that al- lows easier coupling (i.e. without gearbox) with generators (or mechanically driven equipment, if required) and a more effective containment of the leakages, since they are fully recovered avoiding the necessity of continuous refilling. In the following paragraphs three different solutions are presented, to address different needs. 2. CO2 BRAYTON ENGINE 2.1 HOW IT WORKS AND MAIN BENEFIT BH is very deeply experienced with CO2 compression up to supercritical state, as referenced by more than 100 com- pressors delivered since 1959 with a capacity up to 19000 Nm3/h and a discharge pressure up to 324bara. As a consequence of this expertise, BH developed a pat- ent-pending system for waste heat conversion into electric power that exploits supercritical CO2 circulating in closed loop in a Brayton cycle through a reciprocating expander/ compressor group, connected with the electrical generator by a common crankshaft, and relevant coolers, other than auxiliaries, according to the scheme shown in Figure 1: From mechanical point of view, the specific design of the components, such as a proper arrangement of cylinders of the reciprocating expander/compressor group, the selec- tion of suitable piston sealings and materials, the adoption of fully actuated valves, is expected to positively influence the polytropic efficiency. Therefore, considering its thermodynamic efficiency, the Brayton regenerative cycle reaches an overall efficiency (electrical or mechanical power output to thermal pow- er input ratio) higher than 20% (considering air at 35°C as cooling medium (severe condition) and exhaust gas temperature ≥ 450°C) slowly decreasing as the available exhaust gas temperature decreases, at same temperature approach on the hot section of the WHRU (see Figure 2). Figure 2: CO2 Bryton Engine efficiency vs. Exh. T (with cooling air @ 35°C). 2.2 ENHANCED CYCLE CO2 exiting from reciprocating expander, although cooled in the regenerator to recover enthalpy by heating com- pressed CO2, so increasing the cycle efficiency, before entering the final cooler and close the loop is still warm enough to heat a secondary fluid, that can work in a bot- tom cycle to produce additional power. Figure 1: CO2 Brayton Engine The advantages of use reciprocating machines are linked to their robustness, reliability, wide rangeability with low ef- ficiency decrease at partial loads, affordable price, reduced start-up time, low expertise required for maintenance. Fur- thermore, considering the high power density related to the supercritical CO2 power plants, for the size of 0.5÷1MWe the main advantage of reciprocating machines against solutions with rotating ones is due to the much lower speed (one order of magnitude less, i.e. up to 1000rpm for BH developed a further patent-pending system for waste heat conversion into electric power that combines the CO2 Brayton cycle shown in the previous paragraph with a bottom Rankine cycle with an organic or a refrigerant fluid, with reciprocating expander group, and eventually the pump, connected with the electrical generator and with CO2 reciprocating expander/compressor group by a com- mon crankshaft, according to the scheme shown in Figure 3. Once more, the low crankshaft speed of reciprocating
42 PIPELINE TECHNOLOGY JOURNAL RESEARCH / DEVELOPMENT / TECHNOLOGY Figure 3: CO2 Brayton cycle combined with a bottom Rankine cycle system allows the direct coupling of CO2 expander/com- pressor and bottom cycle expander, as well as acting on cylinders displacement it is possible to elaborate the dif- ferent volumetric flowrates. To perform the same scenario with rotating machines, it would be necessary an integrally gear machine, significantly decreasing the performances and increasing its complexity. In the same hypotheses of simple CO2 Brayton cycle, over- all efficiency reaches values around 25%. 2.3 POTENTIAL APPLICATIONS FOR PIPELINE Wherever a primary heat source is available, CO2 Brayton Engine contributes to electric and/or mechanical power production with a significant avoidance of fuel consump- tion and greenhouse gas emissions. Even where the electric grid is fully available, CO2 Brayton Engine allows to reduce OPEX (electricity cost) and reduce compressor station CO2 emissions. 3. ORCHILLER 3.1 CYCLE FEATURES AND TECHNOLOGY The waste heat conversion into electricity is not always the most viable option (depending on the specific context) for the pipeline operators, so that the direct conversion into another useful effect (refrigeration) could be a better value. The ORChiller is a patent-pending system by BH for the waste heat conversion into cold energy refrigeration duty, by means of a combination of an Organic Rankine Cycle (ORC) with a mechanical compression refrigeration cycle. It allows to produce chilling service without power generation equipment, by direct mechanical drive of the compression unit, using the same working fluid both for the ORC and for the refrigeration cycle (Figure 4). The two cycles have in common the condenser (that can be air or water cooled). This cycle can also be arranged with double stage com- pression-expansion, improving so efficiency and reaching lower temperature service. CO2 Brayton Engine doesn’t need water, thermal oil or oth- er utilities, is EHS safe, viable for unmanned operation and it requires minor civil works for a plug and play installation. If compared to the well-known heat-to-cold application, the lithium bromide cooling cycle, the ORChiller can adjust
RESEARCH / DEVELOPMENT / TECHNOLOGY PIPELINE TECHNOLOGY JOURNAL 43 are adjustable on the specific application, in a fit-forpur- pose way of design. An intermediate fluid to carry the waste heat must be used, such as thermal oil, as the propane cannot be directly heat- ed through a WHRU by means of direct heating. But in case a non-flammable working fluid like carbon dioxide is used as working fluid, this thermal oil loop can be avoided. OR- Chiller has also been studied to be used with CO2, adding also the advantage of reaching lower chilling temperatures (i.e. -18 °C), in case water is available for the condenser cooling, to enhance compactness. From a turbomachinery point of view, a huge advantage is that the expandercompressor is hermetic type. High reliability service is improved as the hermetic machinery does not use any gas seals system, or lube oil, or gearbox. Magnetic bearings are suggested, so enhancing reliability and keeping the system fully sealed. Moreover, the air cooler condenser fan motors and circu- lation pumps motors can be run in Low Voltage, so that no electric conversion or Medium Voltage switchgear is needed, resulting in easy integration with existing electric infrastructure. The WHRU, when installed on Gas Turbine exhaust, shall be properly selected to minimize backpressure and foot- print. Figure 4: Conceptual ORChiller purpose scheme (GT exhaust application) the chilling service temperature in a wider range, from 5 °C down to -18 °C (in case of propane as working fluid, single stage machinery). The cycle configuration is presented in Figure 5. The working fluid proposed is propane, which is pumped and then heated through the exhaust gas waste heat (i.e. from a GT), then it expands producing the necessary mechanical power to drive the compressor, which is part of the refriger- ation cycle. Both cycles use the same fluid, and this is one of the main advantages of the ORChiller. The working fluid streams after expansion, and after compression, are sent to the condenser, and the two cycles can start again. The expander-compressor machinery is intended to be integral- ly connected on the same shaft, by enhancing the ease of the system. Operability and chilling service temperature Figure 5: ORChiller configuration with intermediate heat transfer fluid (HTF)
44 PIPELINE TECHNOLOGY JOURNAL RESEARCH / DEVELOPMENT / TECHNOLOGY 3.2 MAIN ADDRESSED USES AND TECHNOLOGY VALUE The ORChiller can be applied to enhance the efficiency and reduce fuel consumption and CO2 emission to different industrial and compression plants. The optimal size has been addressed to a 25 MW gas compressor, driven typi- cally by a PGT25/FR5 or similar. In compression systems operating on gas compositions with low dew point, the suction temperature of the com- pressor can be reduced with the ORChiller, resulting in reduction of the required power, enhancing the overall compression efficiency. As an alternative, the capacity of the compression station can be increased with the same fuel consumption. Gas turbines (GT) chilling can be includ- ed also, increasing the available power in the hot days. 3.3 POTENTIAL APPLICATIONS FOR PIPELINE In case of pipeline application, the ORChiller is estimated to be able to increase efficiency of a significant amount by cooling the inlet process gas and consequently reducing the emissions, when allowed by gas dew point specifica- tion, as illustrated in the previous paragraph. Main benefits of this hybrid configuration (which is con- ceptual only) would be a high level of process integration (piping and equipment reduction) and the supplement of power generation. Figure 6: Integrated Turboexpander-Compressor with high speed generator (option for ORChiller base configuration) 4. HYBRID GAS TURBINE 4.1 OVERVIEW From an operability perspective, the design point can be oriented between two scenarios: in one case the ORChiller is designed to keep the pipeline compressor in its oper- ating envelope, otherwise a re-bundle of the compression train has to be considered, in order to match with the new rated condition. Moreover, in case of ORChiller outage, the pipeline compression train would be not impacted. The synergy between mechanical drive gas turbines (GT) with an electric motor has successfully carried out more than 30 years ago mainly in LNG market. The BH Gas Tur- bine hybridization concept here described allows to have helper and generator modes on the same shaft, giving to the operator a full flexibility to manage the plant and the resources, developing a turboelectric-compressor train. Currently heat conversion for refrigeration is done by the well-known lithium bromide absorption units. Differently from lithium bromide technology, the ORChiller can vary the chilling operative temperature, by reaching down to -25 °C, enhancing the flexibility and taking more advantage from the heat 3.4 HYBRID SOLUTION: INTEGRATED HIGH- SPEED GENERATOR OVERVIEW When a small amount of electricity is needed (e.g. self-con- sumption of the pipeline compression station), a develop- ment of the system described above can be also consid- ered; in case of electrical peak load, the balancing between cooling duty and electric production can be directly man- aged by the control system. If a proper residual amount of flue gas enthalpy is avail- able, a hybrid integrated solution machine can be de- veloped, by coupling the turboexpander to a permanent magnet generator with magnetic bearings, without seals system issues and using the same process gas to cool the airgap. As highlighted in the World Energy Outlook 2019 by International Energy Agency, natural gas is accounting today for 23% of global primary energy demand and nearly a quarter of electricity generation. To tackle the energy challenges, it is important to develop smart and integrated networks which function as components of a holistic ener- gy system, including gas, electricity, heat and information technologies (See Figure 7). With the adoption of hybrid GT configuration electricity networks can be actively sustained leveraging on pipeline compressor stations generating additional revenues and providing a positive impact on greenhouse gas emissions. Furthermore, a strategic partnership can be established with an electric distributor, to properly compensate his load demand, stabilizing the network by importing and export- ing energy. From a strategic gas delivery perspective, the hybrid gas turbine configuration allows to use two different primary energy sources to guarantee availability also in case of any electrical grid issue. This feature is not achievable in case of pure electric compression units.
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46 PIPELINE TECHNOLOGY JOURNAL RESEARCH / DEVELOPMENT / TECHNOLOGY Figure 7: Hybrid GT 4.2 HYBRID GT CONFIGURATIONS 4.2.1 LP SHAFT HYBRID (PATENT EP3004601 B1) The main Hybrid GT schematic is composed by an elec- trical machine coupled on gas turbine low pressure shaft with a self-synchronizing clutch between GT and load compressor (See Figure 8). This scheme is applicable to all mechanical drive gas tur- bines (heavy duty and aeroderivative type). Electrical Ma- chine (EM) is connected directly on the compressor shaft using a high-speed motor-generator avoiding the use of a gear box. EM power range could be selected up to 20 MW. A VFD (Variable Frequency Drive) system and the input transformer are used to adjust the electrical network to the motor and compressor needs. It is able to connect with the network frequency with the EM, spinning it at the desired operating compressor point. This flexibility allows control the train in speed or in torque mode in order to match the following equation: P=c*n where P=power; c=torque and n= RPM. The power of electrical machine will be managed by torque. It will be positive or negative in case the electrical machine works as motor or generator. A self-synchronizing clutch allows the engagement and disengagement of the gas turbine automatically, based on the speed difference. Such device is largely used in power plant combined cycle, connecting the gas turbine with the steam turbine. The application varies from a range of pow- er from few MW up to 300 MW and a range of speed from 1000 to 12000 rpm. Hybrid GT concept is applicable to new units or as upgrade on existing turbocompressor units. Of course, to revamp an existing unit, the compressor has to be modified to imple- ment the mechanical shaft connection with the electric motor. The upgrade of compressor shaft allows to adopt the latest stage technology on centrifugal compressor further increasing the overall efficiency. Figure 8: Main Hybrid GT schematic
RESEARCH / DEVELOPMENT / TECHNOLOGY PIPELINE TECHNOLOGY JOURNAL 47 Proposed configuration can work as helper, generator or full electric modes: 4.3 ENVIRONMENTAL IMPACT GENERATOR MODE - Whenever the gas turbine delivered power is greater than the power required by the centrifugal compressor, this is converted into electrical power avail- able, without any interference with the process. HELPER MODE - The EM can be energized converting elec- tricity into mechanical power either to increase the power of GT at full load when it is not enough for the compressor or to share the absorbed power between GT and EM, so unloading the GT. FULL ELECTRIC MODE - VFD Electric Motor can be dimen- sioned to deliver the power required by the compressor, allowing to work in Full Electric Mode, producing without emissions (Zero Emissions Configuration). This mode is particularly helpful in case of electricity cheaper cost or excess of it (i.e. renewable sources). 4.2.2 HP SHAFT HYBRID (PATENT WO2014102127 A1) For two shafts gas turbines (heavy duty and NovaLT mod- els) another simpler schematic is available where electrical machine is coupled directly on high pressure gas turbine shaft. The EM power range depends on the GT model: for a Frame 5 up to 3 MW. This system can operate as Starter and Helper or as Starter and Generator modes and it has the advantage of reduces the impact on brownfield applications (See Figure 9). STARTER MODE - During the starting sequence the VFD modulates the speed/torque to perfectly match the opti- mum firing conditions and acceleration ramp. At the end of the startup sequence the electrical machine can run in de-energized mode without any limitations or switching in the other operating modes. Renewable generation is variable, highly dependent on weather and time of day, and cannot always be turned on at will. The increasing penetration of intermittent genera- tion raises the challenge of how to maintain the balance of supply and demand at all times. The hybrid GT configura- tions give to the operators the possibility to reach a wide range of benefits especially in case of pipeline application. In case of green electricity availability or at low cost with the electrical machine working as motor, the abatement of the fuel leads to a CO2 footprint reduction and economic benefits. On the other side in case of electricity high cost the elec- trical machine can work in generator mode producing elec- trical power for additional revenues or cover compressor stations power consumptions. So, it’s possible to reduce OPEX putting in shutdown the external electric station generator, reducing emissions too. In addition, this configuration allows to stabilize the exhaust thermal load, boosting the WHR system inde- pendently from the compressor process conditions. Generator mode helps also gas turbine efficiency and NOx optimization in conjunction with the DLN/DLE technolo- gies. The full electric mode allows energy storage function by pressure gas accumulation scenario. In fact, the compres- sor driven by the electric motor will deliver flow and pres- sure to the pipeline that acts as energy tank storage. Since there are many variables connected each other, for an operator is quite impossible to evaluate how to proper balance the GT fuel and Power controller. For this rea- son, BH is developing a specific software that manages a tailored dynamic trade off based on real time site process data and economics (See Figure 10). Figure 9: Starter and Helper or as Starter and Generator modes
48 PIPELINE TECHNOLOGY JOURNAL RESEARCH / DEVELOPMENT / TECHNOLOGY Figure 10: A BH development - Software that manages a tailored dynamic trade off based on real time site process data and economics. 5. CONCLUSIONS The three technologies, above described, are viable solu- tions to reduce emissions of greenhouse gases in the pipeline environment and allow to strongly integrate the compressor station with electrical grid. The importance of these technologies, among which is under development in BH, is the message of how BH is intercepting the new market trend of renewable integration in the actual pipeline operator’s perspectives, matching the process needs with opex and emissions optimization. Authors Ernesto Nasini Baker Hughes Lead Mechanical Engineer ernesto.nasini@bakerhughes. com Marco Santini Baker Hughes Clean technology Product Leader email@example.com Simone Amidei Baker Hughes Energy Transition Technology Leader Marco Baldini Baker Hughes Gas Turbine Consultative Service Manager firstname.lastname@example.org Maurizio Vaccaro Baker Hughes Technology Innovation Engineer maurizio.vaccaro@bakerhughes. simone.amidei@bakerhughes. com com
Real-time remote monitoring and risk management of oil & gas facilities subjected to natural hazards Prodromos N. Psarropoulos, Elena Kapogianni; Yiannis Tsompanakis > National Technical University of Athens; Technical University of Crete Abstract The term “natural hazard” is used to describe any natural phenomenon that might have a negative effect on humans and/or the environment. The natural hazards can be classified into two broad categories: geological and meteorolog- ical (e.g. landslides, volcanic eruptions, heavy storms, floods, droughts and high ambient temperatures). Furthermore, it has to be emphasized that in certain geographical regions, such as the wider region of the Mediterranean, are char- acterized by moderate or high seismicity, leading thus to various earthquake-related geological hazards, such as soil liquefaction phenomena, rupture of active seismic faults at the ground surface, and earthquake-triggered landslides. The risk of oil & gas facilities (such as oil or gas pipelines, refineries, terminals, etc.) due to natural hazards is ex- tremely high since a serious damage and especially a total failure of a structural or a non-structural component of a facility may lead to a “natech” (i.e. a combination of a natural and a technological disaster). The evaluation of the risk of an industrial facility requires the quantitative assessment of all hazards along with the realistic evaluation of the vulnerability of the structural and the non-structural components. Therefore, the cost-effi- cient assessment and management of the risk of an oil & gas facility is a demanding task that requires a multi-dis- ciplinary approach. In many cases of oil & gas facilities, the safety requirements are covered by the application of the valid norms and standards during the design phase. Therefore, the accurate application of the design during the construction phase is expected to guarantee an absolutely safe facility. Nevertheless, there are various direct and indirect reasons why the safety (and the serviceability) of an oil & gas facility may be inadequate. The current study tries to describe these reasons and to demonstrate how real-time remote monitoring can significantly contribute to risk reduction.
RESEARCH / DEVELOPMENT / TECHNOLOGY PIPELINE TECHNOLOGY JOURNAL 51 Since some of the industrial facilities are related to the oil & gas industry (i.e. oil refineries, oil or gas terminals, etc.), they comprise fundamental elements of the national and/ or the international energy sector. Their overall risk due to natural hazards is extremely high since a serious damage and especially a total failure of a structural or a non-struc- tural components of an industrial facility may lead to a “natech” (i.e. a combination of a natural and a technologi- cal disaster) leading to injuries, deaths, economic loss, and environmental damages. Figure 1: The relationship between structural risk, hazard, vulnerability, and loss. 1. INTRODUCTION The term “natural hazard” is used to describe any natural phenomenon that might have a negative effect on humans and/or the environment. The natural hazards can be classi- fied into two broad categories: geological and meteorologi- cal (e.g. landslides, volcanic eruptions, heavy storms, floods, droughts and high ambient temperatures). Furthermore, it has to be emphasized that in certain geo- graphical regions, such as the wider region of the Mediter- ranean, are characterized by moderate or high seismicity, leading thus to various earthquake-related geological hazards, such as soil liquefaction phenomena, rupture of active seismic faults at the ground surface, and earth- quake-triggered landslides. It is evident that the integrity of any engineering structure may be threatened by one or more natural hazards. The structural risk of any structure, including the industrial facilities, is directly related not only to the aforementioned hazards, but also to the vulnerability of the structure which depends on the design, the construction and the oper- ational conditions during its lifetime. Depending on the circumstances, the overall risk of any engineering structure is a function of the structural risk and the anticipated cor- responding loss in terms of human lives and/or socio-eco- nomic cost(s) (see Figure 1). The industrial facilities usually include various sensitive engineering structures, such as tanks, pipelines, jetties, buildings, etc., that are potentially threatened by a range of natural hazards, geological and/or meteorological (see Figure 2). (a) (b) Figure 2: Examples of damages and failures of industrial facilities in the past due to natural hazards: (a) damage of a fluid tank in USA due to a tornado in 2019, and (b) natural gas storage tanks alight at the Cosmo oil refinery in Japan in 2011
52 PIPELINE TECHNOLOGY JOURNAL RESEARCH / DEVELOPMENT / TECHNOLOGY Table 1: Various geohazards and their potential consequences to pipelines (after ISSMGE/TC1) The evaluation of the structural risk of an industrial facility requires the quantitative assessment of all hazards along with the realistic evaluation of the vulnerability of the structural and the non-structural components. Therefore, the cost-efficient assessment and management of the structural risk of an industrial facility is a demanding task that requires a multi-disciplinary approach. In many cases of oil & gas facilities, the safety require- ments are covered by the application of the valid norms and standards during the design phase. Therefore, the accurate application of the design during the construction phase is expected to guarantee an absolutely safe indus- trial facility. Nevertheless, there are various direct and indirect reasons why the safety (and the serviceability) of an industrial facility may be inadequate. Table 2: Various meteorological (i.e. climate) natural hazards
54 PIPELINE TECHNOLOGY JOURNAL RESEARCH / DEVELOPMENT / TECHNOLOGY 2. GEOLOGICAL & METEOROLOG- ICAL NATURAL HAZARDS As aforementioned, there exist a variety of geohazards threatening the integrity of an oil & gas facility. Indicative- ly, Table 1, adopted from the Geotechnical & Geophysical Investigations for Offshore and Nearshore Developments report by ISSMGE/TC1, presents the main geohazards and their potential consequences to pipelines. On the other hand, various meteorological (i.e. climate) nat- ural hazards may substantially distress an oil & gas facility, especially during the last decades that the climate change is taking place. Therefore, the operators should design and implement appropriate adaptation and defence measures as proposed in the COM (2013) 216 - An EU Strategy on adaptation to climate change, and more specifically in the SWD (2013) 137 - Adapting infrastructure to climate change and the EU Non-paper Guidelines for Project Managers: Making vulnerable investments climate resilient (see Table 2). 3. REAL-TIME REMOTE MONITORING As aforementioned, the real-time remote monitoring is di- rectly or indirectly related to the risk of a facility. There are at least six (6) reasons why this happens: a) Human errors and/or negligence during the design, construction and/or operation phase cannot be excluded. Additionally, all national and international standards and norms are not perfect and they are get- ting improved every 10 to 20 years, a time period which is shorter than the usual lifetime of an oil & gas facility. b) All input data of the design have a certain degree of uncertainty, especially when geodata are concerned. In parallel, climate change makes this uncertainty even higher. For example the heavy rainfalls increase the risk of landsliding not only under static conditions, but under seismic conditions as well. Figure 3 shows two examples of earthquake-triggered landslides in areas where the groundwater table was relatively high (due to the local geological and meteorological conditions). The first example is a huge mudslide that took place during the 2001 El Salvador earthquake, while the sec- ond example is the destructive Nikawa landslide that occurred during the 1995 Kobe earthquake in Japan. c) Seismic design relies on seismological studies which are based on probabilities and statistical interpretation of data. d) Some projects are located in remote isolated areas with limited accessibility. Figure 4 shows two exam- ples of areas with limited accessibility. The left-hand side picture shows the high mountains of central Albania where the new high-pressure gas pipeline TAP (Trans Adriatic Pipeline) is currently being constructed. Note that the low accessibility is attributed not only to the high altitude of these mountains, but to the existence of snow during at least four months of each year. The right-hand side picture shows the seabed of the Mediterranean Sea where it is evident that the wa- ter depth in some areas is of the order of kilometers, making thus the accessibility (and any potential repair) extremely difficult. e) As modern seismic design allows certain damage levels, a relatively small aftershock may cause the collapse of a damaged structure if the structural dam- ages of the mainshock have not been identified and repaired quickly. Figure 5 shows three damaged oil tanks just after the 1999 Kocaeli earthquake in Turkey. Note that, although the tanks are identical in shape and dimensions, they have the same foundation condi- tions and they were excited by the same strong ground motion, they behaved differently due to their different mass (i.e. liquid content). The right oil tank that has survived the main shock could have collapsed during a strong aftershock. f) Finally, an early-response system (such as a smart block valve that connects two or more components of a facility) may decrease the loss of new or old facilities, and therefore the total risk. Figure 6 shows the main oil tank farm of Cyprus where tanks and pipelines are connected with a marine jetty. It is evident that the application of an early-response system could sepa- rate the various components of the facility in case of an emergency. In order the operators to have a remote and complete real-time view of the potential natural hazards and their potential consequences to the oil & gas facilities under ex- amination, especially in areas characterized by seismicity, there is need for the installation of the following: a) Accelerometers b) Inclinometers, topographical instrumentation, and/or satellites c) Strain gauges and/or fibre optics and the development of early-warning systems, and/or early-response systems. The accelerometers are required for the recording of the triggering (i.e. the seismic motion at the ground base and at the ground surface). The inclinometers, topographical instrumentation, or satellites can be used to measure the permanent ground
RESEARCH / DEVELOPMENT / TECHNOLOGY PIPELINE TECHNOLOGY JOURNAL 55 (a) (b) Figure 3: Earthquake-triggered landslides during: (a) the 2001 El Salvador earthquake and (b) the 1995 Kobe earthquake in Japan. Both of them are somehow related to the groundwater table conditions. (b) Figure 4: (a) The high mountains of central Albania that TAP pipeline is crossing, and (b) the seabed of the Mediterranean Sea. In the first case the accessibility of a facility or a pipeline is rather limited, while in the second case the accessibility in deep waters is almost impossible. Figure 5: Damaged oil tanks during the 1999 Kocaeli earthquake in Turkey Figure 6: Oil tanks and pipelines connected with a marine jetty in Cyprus
56 PIPELINE TECHNOLOGY JOURNAL RESEARCH / DEVELOPMENT / TECHNOLOGY displacements due to slope instabilities, soil liquefaction phenomena, and/or fault ruptures at the ground surface. Additionally, an early-warning and an early-response sys- tem connected with strain gauges, fibre optics, etc. is re- quired to measure the structural distress (e.g. strain levels). Finally, combined monitoring of oil & gas facilities, and especially of critical infrastructures, is required in order to achieve in parallel safety, security and cyber-security. Note that an onshore, near-shore or offshore critical infrastruc- ture may be very vulnerable to a terrorist attack (physical and/or cyber) just after a serious damage that has been caused by a natural phenomenon (e.g. earthquake, tsuna- mi, storm, etc.). 4. CONCLUSIONS The current paper refers to remote real-time monitoring and early-response systems that should be applied on oil & gas facilities that are subjected to geological and/or mete- orological natural hazards. As it was described, there exist various benefits since they: a) can substantially contribute to the reduction of the risk of various oil & gas facilities, either onshore or offshore. b) may be very effective in the case of long lifelines (i.e. pipelines and cables) that are crossing extensive and remote areas characterized by potential geohazards and various meteorological conditions. c) are very promising as new technologies (on sensors, telecommunications, and automations) are leading to a decrease of their cost and an increase of their reliability. References http://ec.europa.eu/clima/policies/adaptation Geotechnical & Geophysical Investigations for Offshore and Nearshore Developments, Technical Committee (TC) 1, International Society for Soil Mechanics and Geotechnical Engineering (ISSMGE), September 2005. Chiocci F., Cattaneo A., Urgeles R., Seafloor mapping for geohazard assessment: state of the art, Marine Geophysical Research, Springer 32:1–11, 2011. Dean, R., Offshore geotechnical engineering: Principles and practice, London: Thomas Telfold Limited, 2010. Godey S., Bossu R., Guilbert J., Improving the Mediterranean seismicity picture thanks to international collaborations, Physics and Chemistry of the Earth, 63, 3-11, 2013. O’Rourke M.J., Liu X., Seismic design of buried and offshore pipelines, Monograph Series, Multidiscipli- nary Center for Earthquake Engineering Research, (MCEER), 2012, Randolph M., Gourvenec S., Offshore Geotechnical Engineering, CRC Press, 2011. Authors Yiannis Tsompanakis Technical University of Crete Prodromos N. Psarropoulos National Technical University of Athens email: email@example.com Elena Kapogianni National Technical University of Athens
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GRP Piping Failures Ali Assi > Amiantit Qatar Pipes Abstract Glass-fibre Reinforced Plastic pipe (GRP) systems, also known as FRP pipe systems, have been successful in the world’s markets for more than 50 years. During this time, they have developed into a modern pipe material that is predominantly convincing thanks to its lightweight, corrosion resistance, a smooth inner surface, and easy installa- tion. Continuously wound GRP pipes are also popular in AP and the Middle East where they have provided well-accept- ed concepts to many industries and in many applications for many years. GRP pipes also had a proven design life known in some case histories for a design life of more than 33 years. All piping, in general, has a certain requirement related to design and installation. GRP piping as a semi-rigid materi- al shares over 80% of these requirements, in this paper we will highlight the remaining specific requirements related to system design, materials qualification, and site installation. Although we will try to present several modes of failure of GRP piping as real cases in terms of catastrophic failure, weeping De-lamination, cracking. we will share several root causes reports identifying what went wrong in terms of installation, design, operation, and testing. The analysis will not consider visual criteria only, but also some engineer- ing tools and NDT methods/techniques to identify the defect, type, size, location trying to propose the best solution to avoid reoccurrence.
1. INTRODUCTION Piping is the most common component in a construction site which is used to transport fluids. Since several de- cades the importance of this component became crucial and for that several standards from ASME, ASTM, ISO, API, BS, DIN, and others, have been published to cover the re- quirement of piping including raw materials, design condi- tions, system design, grades, rating, fittings, joints, flanges, accessories, testing, inspection, installation, commission- ing, operation, maintenance, and rehabilitation. Standards could be a design code which is having several categories (design conditions, pressure design, flexibility and stress intensification, material, standards, fabrication and assem- bly, inspection and testing) like ASME B 31.1, B31.2, B31.3, ISO 14692, or it could be a piping specification document like ASTM D 3517, BS 5911. Other standards could be an auxiliary document related to testing, inspection, installa- tion or other.  GRP Glass Fiber Reinforced Polyester material as one of piping materials and due to its versatility it is used in sev- eral applications and services like gravity, high pressure, low pressure, seawater, potable water, irrigation, industrial waste, cooling water, wastewater, circulating water, sewer, firewater, above ground, underground, on ground, subsea, ducting and more applications. In this paper, we will highlight the shared requirement of GRP piping with other materials, and then we will demon- strate the special requirements of GRP piping which make it unique from other materials. We will explain several failure modes for GRP piping some case histories including root cause analysis of several failures. 2 PIPING REQUIREMENT (GRP VS OTHER): 2.1 ER, CHEMICAL WASTE, WASTEWATER): GRAVITY SEWER/ DRAINAGE UG (SEW- In gravity application, the client needs to construct pipe which can handle at least the below requirement: • Availability of piping material with all components and • accessories. Long design life, (50 – 100 years) with lower mainte- nance cost • Minimum leakage and infiltration incidents which are • • and environmental impact also. Good corrosion resistance internal and external includ- ing biological and gaseous medium. Smooth vs rough surface, which will have an impact on pipe sizing for gravity flow. • High abrasion resistance to water jet cleaning • External load resistance at short term and long term RESEARCH / DEVELOPMENT / TECHNOLOGY PIPELINE TECHNOLOGY JOURNAL 59 • Adapting to special design conditions like road crossing, shallow depths, high wheel load, water table, settlement.  GRP pipes dominate the best choice material for above service and here is the proof: 1. Design proof: GRP pipes design has been done con- sidering long term behavior as per ASTM D 3681 where pipes are over deflected along with Sulfuric acid solu- tion which is a case simulating a gravity sewer, Amiblu R & D facility has performed a type test results up to 30 years as stated by Mr. Hogni in his interview. Refer to figures 1 and 2. Figure 1: Strain Corrosion Test Amiblu Center  Figure 2: Test data for Hobas and Flowtite Pipes for 40 years, results extrapo- lated to 150 years.  2. Flexibility vs Rigidity: GRP considered unique ma- terial between flexible (PVC, PE) and Rigid (RC, VC). Rigid pipes fail by cracking mode under ring bending loading, unlike flexible pipes that are deforming in a deflected mode. Dieter Scharwächter consulting ex- plained the difference between flexible pipe and rigid pipe in buried condition, rigid pipe is more rigid than the soil and it bears the burden of external loading due to soil movement, water table fluctuation, settlement
60 PIPELINE TECHNOLOGY JOURNAL RESEARCH / DEVELOPMENT / TECHNOLOGY along with dead and live loads and cracks developed with time, while the flexible pipe react in a heavy defor- mation mode but with a minimum number of crack- ing. in GRP take advantage of failure mode and it has somehow higher stiffness and strength than traditional plastics (PVC, PE) refer to figure 3.  Figure 3: Rigid and Flexible Pipe Loading with the surrounding soil 3. Abrasion resistance: GRP pipes with special liner consideration has been improved to meet high-pres- sure water jet cleaning standard up to 120 bar nozzle pressure and at an angle less than 30 Degrees refer to figure 4. Figure 4: GRP layers with a special barrier liner for high water jet resistance, Fowtite product guide sewer pipes. 2.2 LOW-PRESSURE PIPES UG UNRESTRAINED SYSTEM (SEWER, IRRIGATION, WATER, SEAWATER) In pressure application underground pipes, the client will need to demonstrate the below requirement: • Availability of piping material rated pressure • Long term design life (50 – 60 years) at lower mainte- nance cost. Low friction and lower pumping cost. Eliminate failures or leakage to avoid major shut- downs. • • • • Good corrosion resistance especially for external (soil, groundwater). Resistance to soil traffic combined with internal pres- sure. Resistance to soil traffic combined with a vacuum. • • Adapting to special design conditions, road crossing, connection to chambers. Thrust blocks for fittings. • In addition to the advantages in paragraph 3.1 (1 and 2), GRP pipes are considered as a well-accepted choice for above service especially for seawater, irrigation, treated sewer due to: 1. 1. GRP Pipes as semi-rigid materials are designed based on long term hydrostatic design basis as per ASTM D 2992 where minimum 18 samples are pressur- ized to high pressure to induce a failure under creep loading, the period for this test will reach to 14 months, and data will be used to pressure class demonstration. Unlike metallic piping which is designed based on cor- rosion rate, where metallic piping will experience pipe wall thinning risk of piping system failure is increasing with time. Pressure class of GRP pipes is selected to meet min- imum working pressure and temperature and with a factor of safety between 1.5 to 2 depends on different standards, and the value is calculated from the extrap- olated value (50 years or more). HDB / Stress t Pres- sure Class >= 1.8 (As per AWWA M45) refer to figure 5. Figure 5: Typical regression line (HDB Test results as per ASTM D 2992). Unlike steel piping where pipe wall design will be relying on corrosion rate MPY (millimeter per year) to determine the design life. Steel pipe as a conductive medium along with high conductive soil (resistivity less than 5000 Ohm-cm) will not survive without ca- thodic protection. Refer to table 1 where typical aging rates vs soil resistivity. The risk of catastrophic failure is increasing with time for metallic piping due to wall thinning and weakening which could occur at the sudden change in pressure, or surge incident during pump start-up or valve open-
Table 1: Typical soil resistivity vs corrosion rates for steel pipes. RESEARCH / DEVELOPMENT / TECHNOLOGY PIPELINE TECHNOLOGY JOURNAL 61 LOW-PRESSURE PIPES FOR AG OR 2.3 UG, RESTRAINED SYSTEM (WATER, SEA- WATER, CHEMICALS, PROCESS). For this application for pressure below 50 bar, the client will request to ensure: • Piping availability at required pressure and tempera- ture. • Design life (20 – 50 years) • UV resistance • • Eliminate failures to avoid major shutdowns. Good corrosion resistance and additional corrosion protection may be required Good vacuum resistance Resistance to water hammering and dynamic load • • • Vibration if any • Minimum sagging at desired spans • • Resistance to fatigue System design is required to combine several loading conditions by using computer software like Caesar II. Chemical resistance chart if any • • High-temperature resistance chart if any • Resistance to soil load, traffic, settlement in case of underground installation. Figure 6: External corrosion in DI Pipes, High ing/closing refer to table 2. The risk of catastrophic failure is increasing with time for metallic piping due to wall thinning and weakening which could occur at the sudden change in pressure, or surge incident during pump start-up or valve open- ing/closing refer to table 2. 2. Flowtite Norway has a case study proofing the design life of the GRP pipe is more than 30 years refer to figure 7. In the power plant north of Lillehammer and due to planned shutdown, Flowtite has taken out the sample from pipeline 30 years in operation, the sam- ple looks brand new pipe with a smooth surface and no signs of aging or visible cracks. Figure 7: Flowtite pipe sample taken out from service after 30 years of opera- tion. Piping for this category is widely used in oil and gas, power plants, desalination plants, sewage treatment plants, and other industrial sectors. Major clients recommend the use of GRP in this service considering the below criteria: 1. Stability in UV: GRP which is manufactured using thermosetting is more stable in hot weather and UV radiation, old samples exposed to UV have shown a change in color only and minor degradation. In all cases for an aboveground application, it is required to use an additional UV inhibitor to ensure the maximum stability of the piping. Also, it is well known that GRP surface radiation temperature in hot weather in the GCC region will be within 10 °C than ambient tempera- ture due to low thermal conductivity in glass fibers, unlike metallic piping where external radiation tem- perature could reach to 80 °C in the mid-day summer season. C. Pechyen1, D. Atong2, and D. Aht-Ong have investigated the effect of UV accelerated exposure of GRE materials with different additives the results shows an increase in mechanical properties after short term exposure to UV and then the results are slightly degreased after 10 years exposure which is consid- ered as minor degradation compared to thermoplastic materials. . 2. 2. Smooth interior surface: GRP pipes have a smooth interior surface and remain smooth with time as we have seen in the Flowtite case study  and Mr. Hog- ni’s interview . This will have an impact on pumping costs if we compare GRP with steel piping.
62 PIPELINE TECHNOLOGY JOURNAL RESEARCH / DEVELOPMENT / TECHNOLOGY 12345678jhbgfcdxsyrdtfghj 2.4 UG (GAS, HOT WATER INJECTOR) HIGH-PRESSURE PIPES AG OR Pipe at a pressure higher than 50 bar, is very critical and clients require to meet some special criteria as per API 15 HR. Concrete shrinks during curing which will create point loads on GRP pipe and risk of damage under shear, and concrete structure settlement will expose the pipe into concentrated bending load and the rocker pipe will be de- flected to accommodate this slight movement. It is worth to know the zone near the structure shall have special backfill procedure (backfill material with cement stabilizer) to ensure a sufficient compaction level is achieved where me- chanical compaction probably is not feasible in this zone, this special compacted zone should be installed along the rocker pipe length and should have an angle less than 45 ° to provide enough internal friction to avoid slippery of layers, refer to figure 8. • • • • The availability of piping with high-pressure joint con- figuration (threaded joint). • Design life (20 – 50 years) • UV resistance • • • High-temperature resistance in some applications. • High gas permeability. • Fire retardancy may be required Conductive pipe most likely is required. Resistance to combined loading, thermal, pressure, bending, vacuum, torque. Resistance to fatigue. Resistance to surge loads and dynamic loads. System design required to combine several loading conditions. Figure 8: GRP Pipe connection to a rigid structure, Flowtite Installation Guide. • Detailed support design and support loads. Pipes under this category require more research and development, and few manufacturers around the globe have developed this tubing technology and qualified them to cover certain sector in oil and gas, the most advantage of composite pipes is its inherited corrosion resistance, however, some clients still prefer to go with metallic tubes provided with additional corrosion barriers. Most likely the composite pipes have limitations in temperature, fatigue behavior. On the other hand, if the pipe system is self-restrained using the laminated joint, the means of protection are different. Sometimes construction can be done with hollo pipe inside concrete this will provide no direct interaction between pipe and concrete structure. Other ways are to wrap the pipe with highly flexible wrap- ping material like sponge rubber, several layers of thin rubber layers at a certain length outside the concrete wall to provide room for pipe flexibility during settlement refer to figure 9. 3 SPECIAL REQUIREMENT OF GRP PIPING: 3.2 JOINT PREPARATION AND INSPECTION: 3.1 PIPE ADJACENT TO RIGID STRUCTURE: Connection of buried pipes or exposed pipes into a rigid structure is very common in a construction site, the rigid structure could be manhole, chamber, pump house, thrust block. GRP pipes require certain measures to avoid dam- age due to structural settlement. As the structured settle- ment is an unavoidable issue. Engineers should deal with the problem by providing some means of protection. GRP pipes in an unrestrained system using double bell coupling have an advantage of angular deflection allow- ance in the coupling, and by using a short pipe length adjacent to the concrete structure. GRP Pipes with coupler or spigot/ bell joint configuration should have rubber gaskets installed for water tightness, pipefitter may have the rubber ring slipped away from groove during pushing. There are few methods to confirm a correct rubber installation as shown below: 1. 2. Insertion of blade piece from coupler edge to ensure that rubber placement is even along the coupler perim- eter refer to figure 10. Internal joint tester: this is applicable for large diam- eter pipes, and it could a good tool to ensure pipes joints are tested, in some cases the final site hydro test could be avoided refer to figure 11.
RESEARCH / DEVELOPMENT / TECHNOLOGY PIPELINE TECHNOLOGY JOURNAL 63 (a) (b) Figure 9: a – flexible wrapping adjacent to concrete. b – simulation of settlement with rubber wrapping Figure 10: Blade pushing inspection in GRP coupler Figure 11: Internal Joint Tester (Amiantit Installation Guide) Figure 12: Spigot / Bell with nipple tester. Figure 13: Layers dripping in laminate: 3. Spigot/ Bell joint test method is done when there are two rubber rings, where the nozzle can be installed in between the groove and water test can be done at joint prior final hydro test. Also testing rubber rings is from outside only, but it should be a good indication for the installer about proper rubber placement refer figure 12. 1. GRP Pipes with self-restrained joint (laminated or adhesive) required skilled pipefitters to prepare the joint. Normally laminated joint higher-skilled requirement than the ad- hesive joint, on the other hand, the adhesive joint is more challenging to inspect the joint after finishing the adhesive, we highlight here few points could be helpful during site installation: The laminated joint which required skilled laminators to perform it should have inspection points related to visual, barcol hardness, and dimensions, however, it is essential to have proper layers dripping (laminate tap- per) to avoid stress concentration laminate ends which could be peel off during operation especially due to thermal and vibration loads refer to figure 13. 2. Pipe ends with misalignment, ovality or different OD are very common at the site, the pipe ends will not be in a perfect position to start the lamination, in this case, special pipe ends preparation should be done, pipe edge grinding, or laminate layers for leveling refer to figure 14.
64 PIPELINE TECHNOLOGY JOURNAL RESEARCH / DEVELOPMENT / TECHNOLOGY Figure 14: Pipe end grinding and additional layers due to misalignment 3. Adhesive joint after finish can have some NDT method to verify if any lack of adhesive occurred or improper adhesion on the pipe/ coupler surface. By using an ultrasound device that should be capable to have sig- nal energy penetrated through the coupler thickness, in general sensor with 0.5 Mhrz should be capable to penetrate and defect a reflection in GRP depth up to 40 – 50 mm. which could be enough for the adhesive coupler. Refer to figure 15. or drop during 4 hours or 24 hours of site hydro test, only a few standards and specification highlighted this issue. In Qatar Construction Specification, it is required to run 24 hours site hydro test, during this time the amount of water to be refilled to the system to accommodate the drop is measured and confirmed to meet certain criteria which is a maximum of 0.02 liter per mm diameter per km length per 24 hours per 1 bar. Shell DEP and some oil gas specification, required to have a pressure chart recorded during the test during, which can explain piping behavior during the test, obviously leakage in piping should be a visible leak or continuous drop of pressure. A pressure chart can be investigated along with temperature variation. Refer to figure 17. Figure 16: Vertical loop with nozzle Figure 15: Ultrasound NDT on adhesive joint 3.3 PIPELINE STABILITY BEFORE THE HYDRO TEST: Pipeline ready for site hydro test should have the following points checked up: 1. Ventilation at highest points, or vertical loops, some- times these piping areas did not have the nozzles accommodated in design drawing or Isometric draw- ing, site team should be aware of it and install it in all necessary places to ensure air is removed during pipe filling. Refer to figure 16. In case of any supports, restraints or thrust blocks are added to the system, this is necessary to be installed as per design conditions before starting the hydro test. 2. 3. Common problems during the hydro test are pres- sure drop, in GRP piping as it has more flexibility than metallic piping could be exposed to pressure variation Figure 17: Pressure chart
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66 PIPELINE TECHNOLOGY JOURNAL RESEARCH / DEVELOPMENT / TECHNOLOGY 4 GRP PIPING FAILURES: 4.2 FLANGE CRACKS: In this paragraph, we are presenting several real failures that occurred in GRP piping, during which the root cause was conducted to investigate the possible cause and avoid. 4.1 FLOODED PIPES: Flooding of pipes is a very common problem especially in GCC where sudden rain heavy rain could occur at any moment during winter or groundwater return to the trench zone during installation. refer to figure 18. The contractor always advised applying a min backfilling layer as soon as the pipe is laid on trench which will help to maintain the pipe in position during the flood. Refer to table 4. GRP flanges are critical parts of the system, they are nec- essary to connect piping into equipment, valves or other. normally GRP flanges are more delicate than other metallic flanges and require special attention during design and in- stallation especially in thickness, type of gasket and tight- ening. It is very common for the installer to have flange connection cases with misalignment and site personnel attend to align the flanges by tightening creating cracks on the neck, these cracks could be major lead to immediate failure during hydro testing or it could be minor causing a failure on long term operation refer to figure 19. GRP Flanges are not designed to carry other equipment loads like valves, it is most common to have all valves supported to avoid transfer loads to flange neck unless detailed analysis is performed to ensure flange is capable to carry the loads, in some cases automated valves are equipped with motors which will create additional moment on the flange during operation. Refer to figure 20. Table 4: Min depth against floatation (AQAP Installation guide) Figure 18: Flooded pipes cases
RESEARCH / DEVELOPMENT / TECHNOLOGY PIPELINE TECHNOLOGY JOURNAL 67 Figure 19: Flange Cracks due to misalignment (a- leak during the hydro test, b- flange leak after operation sour line Figure 20: Flange crack, the valve is not supported Figure 21: Flange cracks due to rerouting
68 PIPELINE TECHNOLOGY JOURNAL RESEARCH / DEVELOPMENT / TECHNOLOGY Stress analysis for all piping is an essential activity, and the purpose for running this works is to ensure piping system is provided with adequate support, control the piping movement, ensure no major loads are transferred to equipment, comply with stress allowable with differ- ent load cases including occasional loads like hydro test, snow, thermal, wind and seismic. It is very common for that installer due to some site obstacles he has to reroute the GRP piping, in some cases, this rerouting will have differ- ent behavior in the piping and will require to ensure stress analysis is satisfied or not. Below is one example of flange cracks where the installer did some rerouting without con- sulting the stress engineer. Refer to figure 20,21 and 22. 4.3 PIPING DAMAGE DUE TO SETTLEMENT: GRP piping going into the rigid structure should be treated carefully as explained in paragraph 4.1, below an exam- ple of GRE piping for fire water entering a building, failure occurred within 1 m from the wall due to settlement. As this piping system is self-restrained with a rigid joint, it is rec- ommended to wrap the pipe with rubber or flexible material to protect the pipe from damage. Refer to figure 23. Figure 23: GRE pipe damage due to settlement Figure 22: Rerouting is done without updating the stress model ( a- case 1, b- case 2)
RESEARCH / DEVELOPMENT / TECHNOLOGY PIPELINE TECHNOLOGY JOURNAL 69 4.4 FAILURE IN CONNECTIONS: GRP pipe coupling or mechanical coupling connection could be a source of leakage due to wrong gasket place- ment or high angular deflection, water will spray at high velocity along with abrasive soil will cause abrasion on external pipe surface which will lead to pipe wall thinning and then catastrophic failure at any pressure change, be- low photos for GRP coupling used to connect two different GRP pipes (restrained and unrestrained), it is well noted that this short piece is pipeline closure which could have different levels and high angular deflection has occurred during installation. refer to figure 24. Mechanical coupling most probably used to connect two different pipes together with same or different outer diame- ter, failure on this coupling is possible if it is not suitable to one of both material, in Figure 30, we investigated several co failures in mechanical coupling (step coupling) con- necting GRP to DI Piping, all of them has a sign of abrasion on pipe spigot nearby the edge of the coupling this is an indication of gasket leakage occurred during pipe opera- tion which was caused by wrong rubber profile along with soil settlement. Refer to figure 31 it shows flat rubber profile used which is not acceptable in GRP piping, the best one used shall be sealing lips (REKA Type). Refer to figure 25 and 26. Figure 24: GRP Coupling failure (abrasion on pipe surface) Figure 25: Failure near mechanical coupling
70 PIPELINE TECHNOLOGY JOURNAL RESEARCH / DEVELOPMENT / TECHNOLOGY Figure 26: Rubber profile of leaked mechanical coupling 5 FUTURE OF GRP PIPING: It is well known that GRP piping requires additional specific requirement that is sometimes more critical than the stan- dard piping requirement. There is poor literature related to GRP piping failures, however, after many decades of using GRP piping, it is necessary to learn from mistakes and improve the quality integrity if piping system during design, fabrication, and installation. NDT technique espe- cially the Ultrasound is a method that is well understood in traditional homogeneous materials, but for composite pipes, the technique is still in an immature phase and a lot of research is required to standardize the method and categorize the defects. UTcomp has developed UltraAnaly- sis method on GRP material to evaluate aging by using an ultrasound device to study the stiffness reflection of poly- mer in the laminate and give digital data about the material status of aging and quality.  6 ACKNOWLEDGEMENT: I would like to acknowledge the top management of Amiantit Qatar Pipe Co represented by Mr Abdulrarhman Al Ansari CEO and Mr Hussein Khatoun GM. References        P. Ellenberger, Piping and Pipeline Calculations Manual. 2010. Indah Water, “A Guide to Sewer Selection Sewer Selection and Installation,” no. 01, p. 27, 2006. A. Hogni Johnsson, “Case Study GRP pipes have a lifetime of 150 years . Here ’ s the proof .,” pp. 1–4. D. Scharwächter, “Statements for the comparison of Vitrified Clay and GRP pipes to be used in municipal sewer pipe lines.,” 2004. J. J. Swihart, Fiberglass Pipe Literature Review. 2016. Flowtite, “30 year old pipeline in fiberglass appears as brand new.” C. Pechyen, D. Atong, and D. Aht-Ong, “Effect of additives on mechanical properties and photo-stability of filament-wound glass fiber reinforced epoxy pipes,” Polym. Polym. Compos., vol. 19, no. 2–3, pp. 161–170, 2011. Author Ali Assi Amiantit Qatar Pipes Technical Manager firstname.lastname@example.org
Prediction of Leak Mass Rate in High-Pressure Gas Pipeline Fang Yuan, Runchang Chen, Boo Cheong Khoo; Yan Zeng; Rongmo Luo > National University of Singapore; National Metrology Centre, Singaproe; Xylem Inc Abstract Gas pipeline leakage poses great threat to the environment pollution and system security. The gas leak mass rate is a key index in the assessment of risk level during pipeline leakage. In this study, compressed air flow in a high-pressure pipeline with leakage is considered, and the leak mass rate is investigated experimentally and nu- merically. Three-dimensional unsteady simulations, with the dynamic mesh technology, were applied to investigate the transient onset of the pressurized air leakage. The numerical model was validated by the experiments through the comparison of the leak mass quantity ratio, defined as the ratio of leak mass rate to inlet mass rate. The rise time of leak mass rate increasing from zero to the peak value was compared at different test conditions. Relations of the peak leak mass rate to the inflow mass rate, pipe operation pressure and leak diameter were scrutinized by various numerical cases. Based on the parameterization results, a non-dimensional correlation was proposed to predict the compressed air leak mass rate through a small leak hole in high-pressure pipeline.
RESEARCH / DEVELOPMENT / TECHNOLOGY PIPELINE TECHNOLOGY JOURNAL 73 compared with the one-dimensional model which neglect- ed the effects of downstream length after the leak. Although there are some works on the discharge rate induced by the pipeline leakage, the majority was based on one-dimensional model or improved ones, in which the adiabatic condition of pipe flow and isentropic condition of flow through leak hole were postulated. However, vigor- ous turbulence dissipation in the process of leakage flow violates the assumption of isentropic process, and, the mass continuity in one-dimensional analysis that all the inflow gas is exhausted by the pipe leakage may not be valid for the small leaks. Above all, despite some investiga- tions on the leakage of distribution pipeline with relatively low pressure, few have been carried out on the leakage in high-pressure pipe. Thus, a three-dimensional numerical model for the leak mass rate in high-pressure gas pipeline is needed, which motivates the present work. In this paper, experimental and numerical investigations on the high-pressure compressed air leakage flow were conducted to explore the effects of inlet mass rate, pipe- line operation pressure and leak hole diameter on the leak mass rate given a fixed pipeline diameter. Transient process of leakage onset was modelled via dynamic mesh method. Experimentally validated model revealed the unsteady characteristics of flow mass rate through leakage hole. A non-dimensional correlation was proposed based on the simulation results to predict the leak mass rate of small leakage. 2. NUMERICAL METHOD AND SIMULATION SETUP To investigate the leak mass rate through a high-pressure pipeline leak hole, three-dimensional, transient, compress- ible air leakage flow was simulated by ANSYS FLUENT. To obtain the details of flow patterns with reasonable computational cost, the large eddy simulation (LES) model was employed in the present study. The filtered governing equations are expressed as  1. INTORDUCTION Gas pipeline is an effective and economic channel for long-distance and distributed transportation due to the ease of installation and retrofits. In-pipe pressure sustains at a high level for long-distance transportation and explo- sive natural gas may cause severe accidents when pipe leakage takes place. Thus, it is necessary to evaluate the hazard of high-pressure gas pipeline leakage, in which the leak mass rate estimation is a hot topic and attracts inter- ests from researchers. Several models were proposed for the natural gas release from the pipe leaks based on internal pipe flow analysis [1- 4]. Based on the classification of subsonic and sonic flow conditions in main pipe and through leak hole, various ex- pressions for leak mass rate estimation were derived from the continuity equation and ideal gas law to cater for differ- ent situations . Three kinds of scenarios were discussed by Montiel, et al : (1) flow in pipe is subsonic and flow through leak hole is sonic; (2) flow in pipe and through leak hole are both subsonic; (3) flow in pipe and through leak hole are both sonic. Small leaks and large ruptures were analysed with hole model and pipe model respectively. However, the hypothesis of mass balance that the leak mass rate is identical to the in-pipe mass flow rate showed some limits on the small leak simulation or transient cases. Dong, et al.  integrated the real gas equation into Montiel’s model to simulate the high-pressure gas leak- age. In addition, the unsteady scenario of gas leaking at large rupture was investigated by considering the closure of inlet valve upon the detection of leakage. Continuous pressure drop after the valve closure led to the transition from sonic to subsonic flow through the leak hole and the relevant governing equations were proposed. Jo & Ahn  carried out an analytical study on the release rate from a high-pressure pipeline leakage. Different from the mass balance assumption in previous research, the mass balance between the pipe flow and the flow at the hole is described by the effective area ratio which includes the influence of discharge coefficient. Flow at the leak point is sonic as the pressure ratio in the high-pressure pipeline is below the critical value. Computational fluid dynamics (CFD) has also been applied to the studies of pipeline leakage. Ebrahimi-Moghadam, et al.  conducted three-dimensional numerical simulations on the above-ground and underground pipeline leakage to introduce a new correlation for gas leak quantity, under the pipeline pressure of 3-5 bar and leak diameter of 5-80 mm. Two equations were proposed to estimate the leak volumetric flow rate above-ground and underground respectively. It was reported that the results obtained via the proposed correlations improved the accuracy by 20%
74 PIPELINE TECHNOLOGY JOURNAL RESEARCH / DEVELOPMENT / TECHNOLOGY The filtered equations are resolved via numerical discret- ization to capture the motion of large eddies while the residual subscale field is approximated via models. In FLUENT, different subscale models are provided to model the residual subgrid field. The wall-modeled large eddy simulation (WMLES) model, a hybrid RANS-LES method better for high-Reynolds flow at a reasonable computation cost, was used in the present study. The computational domain is a straight pipe with the length l = 5000 mm and diameter D = 50.8 mm (2 inch), as shown in Figure 1. The geometry is the same as our labscale setup, which will be illustrated in the next section. Leak hole in the present numerical model is assumed to have a circular shape and extrudes from the inner surface to the outer wall of the pipe with the thickness of 3.1 mm. Different leak diameters are selected to investigate the influence of geometric parameters on the leakage flow. A user-defined fully developed flow condition is incorporated to the inlet boundary condition. The ‘spectral synthesizer’ turbulent generation method is activated to specify the inflow turbulent kinetic energy and dissipation rate. Other boundary conditions are listed in Table 1. 3. EXPERIMENTAL SETUP The present numerical model is validated by experiments through the comparison of leak mass rate. The experi- ments were performed on a Lab-scale pipeline system consisting of a pipeline testbed, compressor facilities and SCADA system. The compressor can boost the gauge pressure of pipeline up to 35 bar and the gas tank helps to stabilize flow. The photo of the lab system excluding the compressor components is shown in Figure 2. Figure 2: Lab system setup photo and auxiliary devices 4. RESULTS AND DISCUSSION 4.1. MODEL VALIDATION In experiments, the leak mass rate was calculated based on the mass balance method . The conservation of mass in pipeline system is expressed as: where Qleak is the leak mass rate, Qin is the mass rate at the system inlet, Qout is the mass rate at the system outlet and Qp is the mass packing rate indicating the observable rate of mass change in a closed system. The comparison of the leak mass ratio (Qleak/Qin) between the numerical simulations and experiments is shown in Table 2. It is found that at lower leak rate caused by the smaller leak hole sizes of 1.6 mm and 3.2 mm, the predict- ed results by numerical simulations agree well with the experimental data, the difference within 10%. In terms of a larger leak hole of 9.5 mm, higher pressure drop induced by the larger leak hole leads to greater depressurizing fluid condition in the laboratory system, and accordingly the leak rate may be lower than the numerical results with a steady boundary condition. This could be the main reason to cause the deviation between simulation and experimen- tal data. Figure 1: Pipe geometry Time interval is set as 1×10-6 s to satisfy the Courant-Frie- drichs-Lewy (CFL) criteria and clearly capture the flow characteristics at the onset of leakage. Table 1: Boundary Settings Table 2: Comparison of leak mass ratios between experiments and simula- tions
RESEARCH / DEVELOPMENT / TECHNOLOGY PIPELINE TECHNOLOGY JOURNAL 75 Figure 3 Leak mass rate caused by different leak diameters (p0 = 36 bar) confirmed via the numerical results, as shown in Figure 4. It is interesting to observe that all the straight line intersects at the origin, indicating that the ratio of leak mass rate to the absolute pipe pressure is constant. Figure 4: Effect of the pipe pressure on the leak mass rate at different leak hole diameters for a fixed inlet volumetric flow rate of 50.2 m3/h Peak values of the leak mass rate caused by different leak diameters are shown in Figure 5. The peak leak mass rate is proportional to the second order of leak diameter when the inlet volumetric flow rate is fixed. This result agrees well with the previous findings in the research on small leaks [4, 5]. 4.2. EFFECTS OF INLET FLOW RATE ON LEAK MASS RATE The peak value of leak mass rate (Qm) is an important index to assess the level of risk during pipeline leakage. Based on the previous one-dimensional analysis, four pa- rameters – pipeline pressure, leak hole diameter, area ratio of leak hole to the main pipe cross-section and inflow con- dition – were found to influence the rate of leakage quan- tity [1-4]. However, the dimensional correlation proposed in recent CFD studies indicated that the leak mass rate was impertinent to the flow information at the pipeline inlet . To settle the contradiction, the impact of inflow conditions characterized by the variation of inlet flow rates is investi- gated in this study. Four different inlet mass flow rates are chosen, and the corresponding leak mass rates are shown in Table 3. It is seen that the maximum and stabilized leak rate is irrelevant with the inflow velocity once the other pa- rameters (pipeline pressure, leak diameter and area ratio) are fixed, consistent with the conclusion from the previous CFD work . Indeed, the inflow condition closely associ- ated with operation pressure was taken as an independent parameter to include the unsteady variations from inlet in the one-dimensional analysis when modeling the dynamic process of valve closing [2, 4]. Table 3 Leak mass rate at different inlet mass flow rate (d = 3.2 mm, p0 = 36 bar) Above all, pipeline operation pressure, leak diameter and the ratio of leak size to pipe cross-sectional area are the factors dominating the dimensional leak mass rate. 4.3. EFFECTS OF DIMENSIONAL PARAM- ETERS ON LEAK MASS RATE Time-marching fluctuations of leak mass rate are shown in Figure 3. It is found that the leak diameter has significant impacts on both the peak value of leak mass rate and the rise time from zero to the maximum value. Larger leak di- ameter induces higher rate of leak loss and it will also take longer time to reach the peak value. The duration from leak onset to the peak time of the leak mass rate is in the order of microseconds for all the diam- eters investigated in the present study, showing transient process of high-pressure pipe leakage. Surge of leak mass rate generates massive gas emission into the surroundings and poses hazards to the environmental security. Moreover, the effects of pipeline operation pressure on the leak mass rate are investigated. The linear relation is Figure 5: Effect of the leak hole diameter on the leak mass rate at different pipe pressures for a fixed inlet volumetric flow rate of 50.2 m3/h
76 PIPELINE TECHNOLOGY JOURNAL RESEARCH / DEVELOPMENT / TECHNOLOGY 4.4. NON-DIMENSIONAL ANALYSIS AND CORRELATION To further explore the dependence of relevant parameters on the leak mass rate, nondimensional analysis is car- ried out. The nondimensionalization of the parameters is shown as below. is linearly proportional to the pipeline operation pressure and the second order of the leak hole diameter. Based on the numerical results, a new non-dimensional correlation inclusive of pressure ratio and diameter ratio is proposed for the leak mass rate generated by small leaks in pressur- ized air pipeline. The correlation could provide a guidance to predict the leak mass rate in real industry applications. where Qin is the inlet mass flow rate, d is the leak hole diameter, D is the main pipeline diameter, p0 is the pipeline pressure in absolute value, pref is the reference pressure in absolute value which is specified as the ambient pressure. The non-dimensional leak mass ratios at different relative pipe pressures p are shown in Figure 6. The leak mass ratio is independent of the non-dimensional pipeline pres- sure due to linear relationship between dimensional leak mass rate and absolute operation pressure, as indicated in Figure 4. The second power relation of relative leak diameter to the leak mass ratio is observed in Figure 7, which corresponds to the results in dimensional analysis. Based on the method of least-squares regression, a new non-dimensional correlation is proposed to evaluate the leak mass ratio of small leaks in high-pressure pipeline where k = 24.7346. 5. CONCLUSION Prediction of leak mass rate through small leak hole in the high-pressure compressed air pipeline was carried out by CFD analysis with the support of experimental validation on laboratory scale. Three-dimensional simulations were implemented to explore the effects of geometric and flow parameters on the leak mass rate. The rise time for leak mass rate surging from zero to the peak value is in the order of microseconds in highpressure pipeline leakage. Larger amount of leakage quantity generated by a larger leak hole takes longer time to stabilize. In terms of para- metric impacts on the peak value of leak rate, the pipe inflow rate was proven to have negligible influence on the leak mass rate as the leakage property is mainly governed by the thermohydraulic conditions near the leak region. Provided the fully developed flow, which is the typical pattern in a long-distance transportation pipeline with a fixed diameter, the leak mass rate induced by small leak- age is only influenced by the pipeline operation pressure and the leak hole diameter. The maximum leak mass rate Figure 6: Leak mass ratio at different relative pipe pressures Figure 7: Leak mass ratio at different relative leak diameters References  Montiel, H., Vılchez, J. A., Casal, J., & Arnaldos, J. (1998). Mathematical modelling of accidental gas releases. Journal of Hazardous Materials, 59(2-3), 211-233.  Yuhua, D., Huilin, G., Jing’en, Z., & Yaorong, F. (2002). Evaluation of gas release rate through holes in pipelines. Journal of Loss Prevention in the Process Industries, 15(6), 423-428.  Jo, Y. D., & Ahn, B. J. (2003). A simple model for the release rate of hazardous gas from a hole on high-pressure pipelines. Journal of hazardous materials, 97(1-3), 31-46.  Dong, G., Xue, L., Yang, Y., & Yang, J. (2010). Evaluation of hazard range for the natural gas jet relea- sed from a high-pressure pipeline: A computational parametric study. Journal of Loss prevention in the Process Industries, 23(4), 522-530.  Ebrahimi-Moghadam, A., Farzaneh-Gord, M., Arabkoohsar, A., & Moghadam, A. J. (2018). CFD analysis of natural gas emission from damaged pipelines: Correlation development for leakage estimation. Journal of cleaner production, 199, 257-271.  Vreman, Bert, Geurts, Bernard and Kuerten, Hans. (1995). Subgrid-modelling in LES of compressible flow. Applied Scientific Research, 54(3), 191-203.  Henrie, M., Carpenter, P., & Nicholas, R. E. (2016). Pipeline leak detection handbook. Gulf Professional Publishing. Chapter 3: Mass Balance Leak Detection, 41-55.
78 PIPELINE TECHNOLOGY JOURNAL SPECIAL CONTENT Europe’s Leading Pipeline Conference and Exhibition ptc for the First Time Virtual • • The first ever online ptc 2020 was successfully held from 30 March to 2 April 2020. The digital version of the renowned Pipeline Technology Conference (ptc) was put in place on short notice by the organizer EITEP Institute, after the Corona-Pandemic led to a global shutdown. • Despite the short preparation time, the ptc-team managed to provide an alternative version, which attracted more than 550 participants and 80 exhibitors, while also enabling more than 100 technical presentations to be shared with the global pipeline community. The organizer announced the creation of upcoming online events after the remarkable success of this unique pilot project. • “We were convinced that our innovative concept would be well received by the global pipeline community, but the success surprised even us. This shows that crisis situations not only present challenges, but also lead to meaningful innovations. We will build on this success and work out new offers that take up the advantages of digital services, such as online ptc 2020”, says Dr. Klaus Ritter, President of the organizing EITEP Institute. The three-day-event took place at the same time as the original Pipeline Technology Conference was planned, therefore allowing many of the already registered partici- pants, sponsors and exhibitors to shift smoothly to the dig- ital edition. The core feature of the online ptc 2020 were the technical presentations, that were accessible as full papers or video files as well as the opportunity to connect and chat with other participants and exhibitors. The central activity feed allowed for the real-time posting of questions or information, contribution to an overall success of the digital event. “We know of course that this kind of online event cannot replace the face-to-face contacts of a real conference with exhibition in Berlin, but we are very grateful that the whole ptc community made it possible to keep the spirit of the Pipeline Technology Conference alive by attending an intense exchange of experience between the partici- pants and by gathering a global audience from all over the world, once again solidifying ptc’s standing as the most international pipeline event worldwide”, expresses Dennis
PIPELINE TECHNOLOGY JOURNAL 79 SPECIAL CONTENT the world’s leading pipeline events”, says Dr. Klaus Ritter. “We are very grateful for the overall support our community gave to us in such challenging times. This encourages us to deliver an even greater event experience next year”, he added. This excitement is shared by many professional pipelin- ers from all over the world, like Marcelino Guedes Gomes from Brazil’s Petrobras: “Congrats to the whole ptc family. The online ptc 2020 was a mark in the history of pipeline conferences.” The outstanding success of the online ptc 2020 has prompted the organizer to create now offers for the global pipeline community. “It has become clear to us that online events have a future in our modern digital world, even without the threat of a pandemic and the need for social distancing. Formats like our online ptc 2020 have the potential to also address specific topics that are not part of the ptc, or niche topics, that have not found their home event yet.”, analyses Rana Alnasir-Boulos, head of EITEP Institutes Business Development department. “We will therefore analyze the market needs and come up with fresh ideas to supplement our Pipeline Technology Confer- ence and Exhibition with additional services”. All papers and videos from the online ptc 2020 will be available for free via the ptc Pipeline Open Knowledge Base on the official ptc website shortly. The 16th Pipeline Technology Conference will take place from 15-18 March 2021 at the Estrel Congress Center in Berlin, Germany. Fandrich, Chairman of the ptc and Director Conferences at EITEP Institute, his gratitude to the many participants. During the first day of online ptc video presentations were available to the audience along with the full papers of all presenters, totaling in more than 100 topics that were presented and discussed during the event. The second day was dedicated to networking, enabling all participants to connect with each other and have their private chat conver- sations with their business partners and potential clients. The last day was under the motto Throwback Thursday. Highlight video presentations from previous ptc-events were available that day and up for discussion. A challenging aspect of this innovative project was the exhibition-part. The traditional ptc, recognized as Europe’s leading pipeline event, is attracting every year more and more exhibitors, who would like to share their technologies and solutions to the global pipeline community in general and to the high number of representatives from pipeline operators in particular. “Exhibitors want to be seen and want to be able to present themselves and their capabili- ties to their clients and potential customers. Therefore, we have established a special section within our conference app, giving every exhibitor the opportunity to be seen by the participants and to describe their services. Of course, this lacks the personal aspect of a trade fair, but it was a good compromise as company representatives were avail- able for questions and requests from their digital visitors.” says Marian Ritter, Director Exhibitions at EITEP Institute. An additional service for the presenters and exhibitors of online ptc 2020 is the publication of all the conference papers in several special issues of the Pipeline Technology Journal. The digital journal is also capable of including the video presentations, thus enabling its readers to consume all relevant information delivered by the online event. Like the original ptc event in Berlin the online ptc 2020 was preceded by a series of seminars on Monday, this time held as online seminars. The topics were “Pipeline Defect Assessments” and “In-Line Inspection of Pipelines and Difficult to Inspect Pipelines”. Both the lecturers and the participants appreciated this format, especially in a time were professional training programs are limited by the current pandemic. “Online ptc 2020 was an overall success, but the upcom- ing Pipeline Technology Conference 2021 of course will return to the established and accepted physical format our participants and exhibitors appreciate the most. The opportunity to engage in intense exchanges of experienc- es with pipeliners, face-to-face, with people from all over the world, is what defines our ptc and what makes it one of
82 PIPELINE TECHNOLOGY JOURNAL COMPANY DIRECTORY . Association IAOT - International Association of Oil Transporters Czech Republic www.iaot.eu/ DVGW - German Technical and Scientific Association for Gas and Water Germany www.dvgw.de Automation Siemens Germany www.siemens.com Yokogawa Japan www.yokogawa.com Certification Bureau Veritas Germany www.bureauveritas.de DNV GL Norway www.dnvgl.com TÜV SÜD Indutrie Service Germany www.tuev-sued.de/is Cleaning Reinhart Hydrocleaning Switzerland www.rhc-sa.ch/rhc/ Coating 1/2 Denso Germany www.denso.de Kebulin-gesellschaft Kettler Germany www.kebu.de POLINOM Russia www.rikol.ru Coating 2/2 Polyguard Products United States www.polyguard.com Premier Coatings United Kingdom www.premiercoatings.com/ RPR Technologies Norway www.rprtech.com/ Shawcor United States www.shawcor.com Sulzer Mixpac Switzerland www.sulzer.com TDC International Switzerland www.tdc-int.com TIAL Russia www.tial.ru TIB Chemicals Germany www.tib-chemicals.com Construction 1/2 BIL - Federal German Construction Enquiry Portal Germany www.bil-leitungsauskunft.de Herrenknecht Germany www.herrenknecht.com IPLOCA - International Pipe Line & Offshore Contractors Association Switzerland www.iploca.com Liderroll Brasil www.liderroll.com.br
LogIC France www.logic-sas.com Construction 2/2 MAX STREICHER Germany www.streicher.de/en Petro IT Ireland www.petroit.com VACUWORX Netherlands www.vacuworx.com Vintri Technologies Canada www.vintritech.com Vlentec Netherlands www.vlentec.com Construction Machinery Maats Netherlands www.maats.com Worldwide Group Germany www.worldwidemachinery.com VIETZ Germany www.vietz.de Engineering ILF Consulting Engineers Germany www.ilf.com KÖTTER Consulting Engineers Germany www.koetter-consulting.com Inline Inspection 1/2 PIPELINE TECHNOLOGY JOURNAL 83 COMPANY DIRECTORY 3P Services Germany www.3p-services.com Inline Inspection 2/2 A.Hak Industrial Services Netherlands www.a-hak-is.com Baker Hughes United States www.bakerhughes.com Intero Integrity Services Netherlands www.intero-integrity.com/ Kontrolltechnik Germany www.kontrolltechnik.com KTN AS Norway www.ktn.no LIN SCAN United Arab Emirates www.linscaninspection.com NDT Global Germany www.ndt-global.com Pipesurvey International Netherlands www.pipesurveyinternational.com PPSA - Pigging Products and Services Association United Kingdom www.ppsa-online.com Romstar Malaysia www.romstargroup.com Rosen Switzerland www.rosen-group.com Inspection 1/2 Ametek – Division Creaform Germany www.creaform3d.com
84 PIPELINE TECHNOLOGY JOURNAL COMPANY DIRECTORY Applus RTD Germany www.applusrtd.com Inspection 2/2 EMPIT Germany www.empit.com Integrity Management Metegrity Canada www.metegrity.com Pipeline Innovations United Kingdom www.pipeline-innovations.com Leak Detection 1/2 Asel-Tech Brazil www.asel-tech.com Atmos International United Kingdom www.atmosi.com Direct-C Canada www.direct-c.ca Entegra United States www.entegrasolutions.com Fotech Solutions United Kingdom www.fotech.com GOTTSBERG Leak Detection Germany www.leak-detection.de Liwacom Germany www.liwacom.de MSA Germany www.MSAsafety.com/detection Leak Detection 2/2 OptaSense United Kingdom www.optasense.com Pergam Suisse Switzerland www.pergam-suisse.ch PSI Software Germany www.psioilandgas.com sebaKMT Germany www.sebakmt.com SolAres (Solgeo / Aresys) Italy www.solaresweb.com VEGASE France www.vegase.fr Monitoring Airborne Technologies Austria www.airbornetechnologies.at Krohne Messtechnik Germany www.krohne.com PHOENIX CONTACT Germany www.phoenixcontact.de/prozess SolSpec United States www.solspec.solutions Operators 1/2
PIPELINE TECHNOLOGY JOURNAL 85 COMPANY DIRECTORY Transneft Russia www.en.transneft.ru/ Operators 2/2 TRAPIL France www.trapil.com/en/ Qualification & Recruitment YPPE - Young Pipeline Professionals Europe International DEHN & SÖHNE Germany www.dehn-international.com/en Safety 2/2 HIMA Germany www.hima.de Signage Franken Plastik Germany www.frankenplastik.de/en Pump and Compressor Stations Surface Preparation TNO The Netherlands www.pulsim.tno.nl Repair CITADEL TECHNOLOGIES United States www.cittech.com Clock Spring NRI United States www.clockspring.com RAM-100 United States www.ram100intl.com T.D. Williamson United States www.tdwilliamson.com Research & Development Pipeline Transport Institute (PTI LLC) Russia www.en.niitn.transneft.ru Safety 1/2 MONTI - Werkzeuge GmbH Germany www.monti.de Trenchless Technologies Bohrtec Germany www.bohrtec.com GSTT - German Society for Trenchless Technology Germany www.gstt.de Rädlinger Primus Line Germany www.primusline.com Valves & Fittings AUMA Germany www.auma.com Further boost your brand awareness and list your company within the ptj - Zwick Armaturen Germany www.zwick-armaturen.de Company Directory www.pipeline-journal.net/advertise
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