bluuebunny/crossref_metadata_2025 huggingface dataset:
Preliminary Surface Fault Assessment and Conceptual Fault Crossing Design of Proposed Gas Pipeline, South-Central Alaska
Authors: Darigo Nancy , Rajah Sri , Boggess Luke
Published: July 2009

A preliminary geologic and engineering study of fault crossings along a proposed high pressure natural gas spur pipeline was conducted in 2005 for the Alaska Natural Gas Development Authority (ANGDA). The route crosses a number of faults that comprise the eastern Castle Mountain-Caribou fault system in south-central Alaska, which is known to be active within 60 miles (100 km) to the west. The route approaches the faults at mostly subparallel angles, resulting in several long coincident crossings, five of which were judged to be potentially active in this study. Maximum displacements of 7 feet (2.1 m) in both vertical and horizontal directions were conservatively estimated for each crossing based on a maximum magnitude 7.0 earthquake and 700-year return period suggested for the western Castle Mountain fault. Preliminary design permanent displacements were recommended as 2/3rds of the maximum. A conceptual buried crossing design in a sloped wall trench with a double geomembrane liner and loose granular backfill would accommodate both vertical and lateral displacements. Additional geologic studies could potentially substantiate longer return periods and lead to a reduction in the number of crossings, crossing lengths, and displacement values. If design displacements are close to allowable settlement criteria, the fault crossings could be eliminated from requiring special design.
Leveraging Technology to Support Enbridge’s Project Compliance During Execution
Authors: Gerla Kevin D.
Published: July 2009

Whether it is an increasingly engaged public demanding a company’s attention to project requirements and commitments or increased expectations of regulators to have project requirements and commitments documented more explicitly than ever, compliance management has become increasingly important for successful project execution. Ensuring compliance with all regulatory requirements and project commitments is Enbridge’s expectation of all its major pipeline projects. The increased focus on compliance management previously described, combined with the historically high number of major projects currently in execution or planned to be undertaken, has resulted in Enbridge enhancing how it approaches compliance. The key modifications include: 1. Implementing a standard compliance management process across all projects and embedding this process within Enbridge’s major project Lifecycle & Gating Control Process. 2. Leveraging available technology to a greater extent in terms of supporting compliance management. This paper will provide insight into Enbridge’s compliance management process, with particular focus on how software is being used to supplement and enhance the process. Specifically, details with respect to how Enbridge’s compliance software is supporting project planning, reporting and querying, notifications, controls, and documentation, all from the perspective of regulatory compliance.
Fitness for Purpose Assessment of 8” Diameter WAGI Gate Valves for Operation at an Uprated Pressure
Authors: Cousens Paul , Jandu Chas , Francis Antony
Published: July 2009

When considering strength parameters, the selection of a valve for a particular application is generally based on the ‘Class Rating’, i.e. the valve thickness is suitable for a given temperature and pressure for a given material. A Liquefied Natural Gas (LNG) station operator identified three Class 600, bolted-bonnet gate valves, operating at cryogenic temperatures, as having pressure relief set-points approximately 7 barg below the 99 barg operating pressure of the process lines on which they were located. This lower set-point impeded the productivity of the lines and also presented a potential hazard from the vented gas. Therefore, to avoid venting, it was requested by the asset owner to determine whether the relief set-points on the gate valves could be safely increased to that of the process lines, without affecting the integrity of the valves. This paper presents how the stresses in the valve bodies were determined by creating a three-dimensional solid Finite Element (FE) model of the valves and adjacent pipework using PATRAN [5] with subsequent linear elastic analyses being undertaken using the general purpose FE code ABAQUS [6] for all loading scenarios. A detailed description of the subsequent fitness-for-purpose assessment to the requirements of PD5500 [10] for operating at the increased pressure is also presented considering the following failure modes; plastic collapse, incremental plastic collapse and fatigue. The results of the fitness-for-purpose assessment of the valves demonstrate that the valves will not fail by general plastic collapse, local plastic collapse or incremental plastic collapse at the increased pressure and that they are acceptable for the proposed fatigue duty. Based on the results of the work presented, and a separate functionality check by the asset owner, the set-points on the gate valves were subsequently increased to the desired level.
Implementation of Alternative Integrity Validation on a Large Diameter Pipeline Construction Project
Authors: Zhou Joe , Murray Alan , Abes Jake
Published: July 2009

Hydrostatic testing has been used by the pipeline industry for many decades as an effective means to demonstrate safety and the leak-free condition of a newly constructed pipeline. However, significant advancements have been made in material, construction and leak detection technologies and quality control processes. These advancements have created the possibility of implementing an alternative to hydrostatic testing while still meeting the original purpose of demonstrating safety and leak-free condition of newly constructed pipelines. TransCanada PipeLines Limited (TransCanada) initiated the development of its Alternative Integrity Validation (AIV) approach in 2004. During 2004 and 2005, TransCanada successfully implemented AIV on a NPS 24 construction project under the jurisdiction of the Alberta Energy and Utilities Board (EUB). With the learnings obtained from the first pilot AIV implementation, TransCanada subsequently implemented AIV on a NPS 42 construction project under the jurisdiction of the National Energy Board (NEB), with CC Technologies (CCT) as the independent third party auditor. As a result of the successful implementation of AIV, the hydrostatic testing requirement was waived for both projects by AEUB and NEB, respectively. This paper summarizes the AIV implementation on the larger diameter pipeline project and provides the perspectives from the pipeline company, regulator, and independent auditor.
A Population Density Based Location Category System for Onshore Natural Gas Pipelines
Authors: Zhou Wenxing , Nessim Maher , Zhou Joe , Rothwell Brian
Published: July 2009

The location class system used in current North American pipeline standards (ASME B31.8 and CSA Z662) is based on structure count included in a specified assessment area. Because the number of people occupying different structures can vary significantly, the population density can also vary significantly for the same location class. Given that the risk (in terms of human safety) imposed by onshore natural gas pipelines is directly proportional to the population density, the current location class system leads to a large variation in the risk level for pipelines with the same class. To achieve more risk consistent designs, a new location category system is proposed in this paper using actual population density data collected from over 19,000 km of gas pipelines in North America. The boundaries between different categories in the proposed system are directly based on population density rather than structure count. One of the key features of the new system is that it uses a separate category for pipelines in unpopulated areas, which are a significant majority of the pipelines included in the study. The implications of the new system are discussed by comparing the lengths of pipelines falling into each category with the lengths of pipelines falling into each location class for all the pipeline data analyzed.
The Development of Large Diameter and Thickness X80 HSAW Linepipe
Authors: Li Weiwei , Huo Chunyong , Ma Qiurong , Feng Yaorong
Published: July 2009

For the requirement of 2nd West-East Pipeline Project of China, X80 large diameter & thickness linepipe with helical seam submerged arc welded (HSAW) were developed, with 1219 mm OD and 18.4 mm WT. Acicular ferrite type and super-low carbon, high Niobium chemical composition pipeline steel was adopted for the base material. The very stringent requirements at −10 °C for toughness, i.e. 220J/170J for average/minimum for pipe body and 80J/60J for average/minimum for weld and HAZ were meet successfully. The yield strength loss due to Bauschinger effect was found lower than 20MPa, which benefited. The very low residual stress level was testified by cut-ring test which cuts a section pipe about exceed 100mm long, and then cut the section apart from welds 100mm along the longitudinal direction.
Key Issues in the Specification of High Strain Line Pipe Used in Strain-Based Designed Districts of the 2nd West to East Pipeline
Authors: Ji Lingkang , Chen Hongyuan , Huo Chunyong , Li Helin , Zhuang Chuanjing , Gong Shaotao , Zhao Wenzhen , Gao Huilin
Published: July 2009

The 2nd West-East Pipeline Project which are building now is the longest of X80 gas pipeline in China even in the world. The geological conditions along it are very complicate. Both stress-base and Strain-based design are all used in the pipeline design. Strain-based design are considered when the pipeline shall via seismic activities, fault crossing and other geological disaster area where ground moving may happen. The pipe which will be used in this kind of special area shall have some special properties besides the properties requirement of the ordinary line pipe. So Tubular Goods Research Center of China National Petroleum Corporation drafted “the Supplementary Technical Specification of High Strain LSAW Line Pipe for the 2nd West-East Pipeline Project”. In this specification, the strain capacity of current X80 line pipe and the testing methods for the mechanical properties are considered. In the mean time, the risk of aging when the pipes are coated is also be noted, and the coating temperature is specified in the specification. Certainly, besides the deformability of the pipe, strain-based design also needs more measures from pipeline construction, girth welding, etc. to ensure the pipeline can endure certain deformation. This paper introduced the general situation of the 2nd West-East Pipeline Project, and several key issues in the specification of high strain line pipe used in strain-based designed districts. At the end of the paper, the mechanical properties and the deformability of X80 pipe which are possible to be manufactured and used in this gas line are be presented.
Reality Check: Improving Real-Time Pipeline Monitoring Using Near Real-Time Fluid Data
Authors: Jutras Joseph , Barlow Rick
Published: July 2009

MBS, the software based leak detection system employed by Enbridge, is a real time transient model and as such requires fluid characteristics of the various batches that enter the pipeline. In the past, of the 25 plus pipelines modeled, only 4 received fluid identifiers from the field. These fluid identifiers are a sub-string of the batch identifiers stored in flow computers located at custody transfer locations. On the remaining pipelines, Enbridge used fluid density from the field to infer fluid type and therefore characteristics. In the past whenever a number of fluids had the same density, MBS assigned a best-guess of fluid type. The ‘MBS Real Time Injection Batch Data’ project was proposed to bring fluid identifiers to MBS on the remaining lines with the purpose of improving MBS’ selection of fluid properties. Since injection points on the remaining lines were not custody transfer there were no flow computers at these locations. An existing application called Commodity Movement Tracking, or CMT, was used to provide fluid names to the leak detection model. CMT holds past, present, and future injection batch information in an Oracle database. Batch identifiers are queried, placed into the SCADA system, and forwarded on to MBS. This paper explores the new approach, introduced by the ‘MBS Real Time Injection Batch Data’ project, of providing MBS with batch identifiers.
Integrity First: Voluntary Performance Reporting in a Goal-Oriented Regulatory Environment
Authors: Saad Ziad A. , McCaig Kim J. , Kenny Brenda
Published: July 2009

In 2007, the Canadian Energy Pipeline Association (CEPA) published a report titled; ‘Integrity First’. This document strives to achieve two goals: 1. For the pipeline industry to communicate performance with its stakeholders and regulators in the areas of pipeline integrity, health & safety and environmental performance. 2. To define performance success quantitatively with appropriate metrics and statistics. This IPC paper will focus on discussing the second goal — most specifically on how voluntary reporting of performance metrics is a necessity in an era of goal-based regulations. For a regulatory agency to effectively manage its dual responsibility to protect the public while facilitating efficient energy transportation, it can be argued that goal-based regulations allow for the best compromise to satisfy both responsibilities. In theory, such regulations ‘set the bar’ at a level that is acceptable to society and it is up to the pipeline company(ies) to determine the most sensible method to achieve the intended goals. Arguably, the pipeline company is in the best position to make decisions on how to safely operate the pipeline with the least amount of risk to workers, the public and the environment while assuring financially viable operations. However, there must be some mechanism to transparently demonstrate to the regulator (and ultimately the public) that the company is meeting the intent of the regulations and not allowing conflicting interests to supersede safety, reliability and environmental responsibilities.
Strain-Based Models for Dent Assessment: A Review
Authors: Gao Ming , McNealy Rick , Krishnamurthy Ravi , Colquhoun Iain
Published: July 2009

The depth-based dent assessment criteria as required by various government regulations and industry codes have served the pipeline industry well by requiring pipeline operators to investigate dents with potentially severe deformational damage. However, the use of depth criterion alone can result in both unnecessary excavations and the mischaracterizing of otherwise severe dents. ASME B31.8-2003 and PHMSA IMP Rules for gas pipelines affecting high consequence areas offer an option for using strain-based criteria and B31.8 provides non-mandatory formulas for strain calculation. Due to complications in dent profile, other formulas in the open literature or those derived by qualified engineers are also allowed by the ASME code. The present paper reviews dent strain calculation methods that are currently available. Comparisons in the calculated strains between methods are made using several case studies. Discrepancies and their effect on the equivalent (or effective) strain are identified. Improvements and alternative strain limit approaches are explored and discussed.
Young Readers Transpetro Program: The Sustainable Development of Community Close to a Pipeline in Goia´s, Brazil
Authors: de Brito Walderes Lima , de Castro Newton Camelo , Bortolon Carlos Roberto
Published: July 2009

A person reading an average of sixteen books per year is considered high even in so-called First World countries. This achievement is even more remarkable if it is performed by children of low-income families. An example is the participants of PETI, Child Labor Eradication Program of Jardim Canedo, a neighborhood located over part of the Sa˜o Paulo - Brasi´lia Pipeline, situated in Senador Canedo, Goia´s, Brazil. In 2007 this community experienced the Striving Readers Transpetro Program, which aims to develop a taste for reading among children. Transpetro expects to be helping to overcome the low-quality Brazilian education, reflected in the 72% rate of functional illiteracy. The chief objective of the Program is the development of art education workshops and the creation of the “Readers Group - What story is that?”. The workshops are meant for the educators, with the purpose of offering tools form them to spur the children into reading through techniques such as story-telling, theater, singing, puppet shows, set constructions and other audio visual resources. The Readers Group is intended for children. Participation is voluntary and offers literary books according to the childs’ taste and literacy. In the first year of operation, Striving Readers Transpetro Program relied on the participation of 100% of the educators in the Art Education Workshops and a commitment of 93% of the Readers Group members. It also played a part in the improvement of the childrens performance in formal school. Furthermore, the Program contributed to the mapping of libraries available for PETI members, supported the assembly of a catalogue of institutes that sponsor striving readers programs and performed workshops with the technical staff at selected institutes to educate them on how to conduct fund raising. Such actions, as a whole, ensured sustainability to the program and promoted a company relationship with the community and with the Regulatory Authority. This is a socially responsible approach to ensuring childrens’ rights are met.
3D Visualization for Hydrocarbon Project Design
Authors: Neurauter Scott , Szeto Sabrina , Tindall Matt , Wong Yan , Wright Chris
Published: July 2009

3D visualization is the process of displaying spatial data to simulate and model a real three dimensional space. Using 3D visualization, Geomatic professionals are enabling pipeline engineers to make better decisions by providing an increased understanding of potential costs earlier in the design process. This paper will focus on the value of visualizing Digital Elevation Model (DEM) data through the use of hillshades and imagery-draped 3D models. From free online DEM data to high resolution Light Detection and Ranging (LiDAR) derived DEM data, the increased availability allows for a broader use of 3D visualization techniques beyond 3D analysis. Of the numerous sources available, two DEM sources will be discussed in this paper, the free low resolution DEM (CDED Level 1) and the more costly but higher resolution LiDAR based DEM. Traditional methods of evaluating potential locations for route and facilities involved a significant cost for ground truthing. Through the use of 3D visualization products, multiple potential locations can be examined for suitability without the expense of field visits for every candidate site. By focusing on the selected candidate locations using a visual desktop study, the time and expense of ground truthing all of the potential sites can be reduced significantly. Exploiting the visual value of DEM permits a productive and cost efficient methodology for initial route and facility placement on hydrocarbon projects.
Integrating the Industrial Automation With Gas Pipelines Process Operations and Measurement From Different Supply Chain Segments of Gas Production Anticipation Plan - PLANGAS
Authors: Salcedo Fernando , Maia Alexandre
Published: July 2009

In order to guarantee future supplies, PETROBRAS is deploying the Gas Production Anticipation Plan – PLANGAS which will increase domestic gas supply to the South-South East regions. Mexilha˜o Field is considered strategically for the Brazilian market gas supply chain, as it is one of the five production complexes to be installed at Santos Basin and have production forecast for up to 15 million m3 of gas per day and twenty thousand barrels per day of natural gas condensate. Mexilha˜o platform - PMXL-1 will be installed at 172 meters water, will export the gas production through 34 inches pipeline with 146 kilometers of extension from the off-shore unit up to an on-shore gas treatment facility, called Unidade de Tratamento de Gas Monteiro Lobato - UTGCA at Caraguatatuba, Sa˜o Paulo. The Gas Treatment Plant will have a processing capacity of 15 million m 3 per day of gas on its first stage, and will produce, as end products specified natural gas for consuming, liquefied natural gas (LGN) and the condensates, such as C5+. After processed in the UTGCA, the natural gas will be dispatched through a 26 inches pipeline up to a future Taubate´ Compression Station at Taubate´, SP, to be connected to a main gas pipeline called GASTAU. This 26″ pipeline is about 100 kilometers long, from Caraguatatuba to Taubate´. This paper intent to present the implementation of such enterprise, where it is affecting at least three different segments within PETROBRAS. The main challenge will be to integrate different requirements and specifications from those three segments and their supply chain, in ways that the overall figure does not impact the enterprise and the time schedules, requirements and operation wise work. Those three segments E&P, Gas and Energy BU, Transport, will also interact with a fourth player, PETROBRAS Engineering department, responsible to contract the engineering design, construction and assembly of all parts, following each segment standards. The main goal of such work is to achieve a process data real time collection, visualization and operation, coming from different sources as gas pipelines, process operations and measurement, with efficiency and reliability to fulfill each segment requirements in an integrated way that no duplication or waste of money and time occurs.
Pipeline Monitoring and Real Time Accident Management
Authors: Assilzadeh Hamid , Gao Yang
Published: July 2009

Pipeline accidents are usually caused through failures, vandalizations, or other environmental accidents like hurricanes, earthquakes and floods. This paper describes the design of an integrated system for real time monitoring and management of pipeline accidents in land and sea environment. This study focuses on oil, gas and other hazardous spill accidents caused by the pipeline transportation system. Multisensor applications for pipeline failures detection and hazard monitoring can be conducted with appropriate models in GIS and internet based communication infrastructure to provide a solution for real time pipeline accidents contingency planning and emergency response. The system architecture includes several models in GIS environment which support disaster management and decision making through provision of various thematic maps, and a module called command and control which is designed for managing and coordinating pipeline accidents response. Command and control system coordinates all tasks related to the accident emergency response through management and administration office. The structure also includes web based accident data dissemination scheme through internet portal which act as a communication system to connect accident managers in administration office with accident relief and operators on the ground. These new approaches in geomatics applications for pipeline accident emergency response can be implemented in other accidental hazards monitoring and management in the environment.
The Importance of “Significant” SCC Data Reported to the National Energy Board: An Update
Authors: Paviglianiti Joe , Murray Alan , Harrison Jason
Published: July 2009

The National Energy Board (NEB) held an Inquiry in 1995 to determine the extent of knowledge and occurrence of SCC on Canadian oil and gas pipelines. The Report of the Inquiry, which was published in December 1996, issued 27 recommendations to promote public safety by encouraging the sharing of information on the extent of SCC and methods for managing and mitigating it. A major recommendation of the Report stated “that the NEB requires companies to report immediately to the NEB any finding of “significant” SCC and any immediate mitigative actions taken...” The definition of “significant” SCC is based on the definition adopted by the Canadian Energy Pipeline Association (CEPA) at the time of the Inquiry. Subsequently the NEB has required companies to submit this information and has used it to monitor the extent of and management of “significant” SCC on their regulated pipelines. This paper examines trends identified from the over 500 “significant” SCC reports submitted to the NEB. The analysis examines trends associated with product shipped, coating type, pipe grade, year of manufacture and SCC location on the pipe. In addition the paper will highlight the length and depth of “significant” SCC features, their methods of detection and the mitigation steps used to reduce any threat posed by the SCC. From the information presented in the paper, companies and regulators should be able to compare their “significant” SCC findings with the NEB average and in so doing aid in the continued management of SCC.
Effect of Pressure Loading on Integrity Management
Authors: Tiku Sanjay , Dinovitzer Aaron , Ironside Scott
Published: July 2009

Integrity assessment or life predictions for in-service pipelines are sensitive to the assumptions they rely upon. One significant source of uncertainty is the pipeline operating pressure data often captured and archived using a Supervisory Control and Data Acquisition (SCADA) system. SCADA systems may be programmed to collect and archive data differently from one pipeline to another and the resulting pressure records can be significantly different on the basis of the sampling techniques, data processing and the distance from pump and compressor stations. This paper illustrates some of the issues involved in pressure load characterization and is based upon work sponsored by the Pipeline Research Council International (PRCI). A series of sensitivity studies using fatigue crack growth calculations have been carried out to evaluate several factors that can influence crack stability and growth predictions that are often employed in pipeline integrity planning and repair programs. The results presented will highlight the issues related to performing integrity management based upon pump/compressor discharge or suction SCADA data to characterize the potential severity of pressure fluctuation or peak pressure dependent defects, illustrate the differences in fatigue crack growth rates along a pipeline segment and demonstrate the complexity of pressure cycle severity characterization, based upon distance from discharge, elevation, hydraulic gradient, for different sites along the pipeline route.
Development of a Pipeline Wrinkle Material Ultimate Limit State: Full Scale Modeling
Authors: Semiga Vlado , Tiku Sanjay , Dinovitzer Aaron , Zhou Joe , Sen Millan
Published: July 2009

While the formation of a wrinkle in an onshore pipeline is an undesirable event, in many instances this event does not have immediate pipeline integrity implications. The magnitude or severity of a wrinkle formed due to displacement controlled loading processes (e.g. slope movement, fault displacement, frost heave and thaw settlement) may increase with time, eventually causing serviceability concerns (e.g. fluid flow or inspection restrictions). Pipe wall cracking and eventually a loss of containment involves contributions from the wrinkle formation process, as well as wrinkle deformations caused by in-service line pressure, temperature and seasonal soil displacements. The objective of this paper is to provide an overview of the ongoing research efforts, sponsored by TransCanada PipeLines Ltd, towards the development of a mechanics based wrinkle ultimate limit state that may be used in future to evaluate the long term integrity of wrinkled pipeline segments. The research efforts include testing and non-linear finite element modeling of a full scale wrinkled pipeline segment. This paper outlines the development of the full scale finite element model, including the detailed material model development, used to estimate the fatigue life of the experimental full scale fatigue test specimen. A comparison is then carried out between the experimental results and the results from the finite element analysis.
Numerical Simulation of Weld Thermal History for Pulsed GMAW Process
Authors: Chen Yaoshan , Wang Yong-Yi , Gianetto James
Published: July 2009

Pulsed gas metal arc welding (P-GMAW) is one of the most effective joining methods used for mainline field girth welding of large diameter, long distance pipelines. Single torch and single wire P-GMAW utilizing narrow-groove weld geometry has been applied extensively in both onshore and offshore pipeline constructions. The industry has a desire to increase welding productivity by the development and application of multi-wire variants of P-GMAW such as tandem-wire and dual-torch processes. These varieties of P-GMAW processes have their unique characteristics which affects the heat transfer and resulting microstructures in the heat-affected zone (HAZ) and deposited weld metal. These unquie features need to be considered in the welding heat transfer analyses. This paper presents heat transfer analyses of various P-GMAW processes with a consistent heat source model and its associated thermal boundary conditions. The objective of the study is to extend the thermal analysis procedures of single-wire P-GMAW to the wider range of P-GMAW processes. To validate the thermal analysis models, the predicted temperature histories (cycles) and cooling times for welds produced under different pre-heat temperatures and different P-GMAW processes were compared with experimentally measured thermal histories. Generally good agreement between the predicted and measured thermal histories was achieved. The areas of further refinement of the thermal analysis models and experimental measurment procedures were identified.
Internal Corrosion of Unpiggable Liquid Facility Piping
Authors: Radmard Shadie S. , Engen Donald L.
Published: July 2009

Historically, pipeline operators have not had the same focused integrity programs for facility piping when compared to those established for mainline systems. This is in part due to the way facilities (stations and terminals) are configured – various diameter pipes, elbows and fittings restrict the use of ILI inspection and minimise the use of other types of tools. Management of facility piping should consider all pipes; however, the focus of this paper is the identification and remediation of internal corrosion of dead legs, either idle or low flow pipes, at station and terminal facilities transporting various types of crude oil products. The severity of internal corrosion found on these segments can range from severe to relatively corrosion free. Inspecting these segments with inspection tools not only confirms pipe condition but also the operator’s rationale for segment selection, inspection method(s) being implemented, mitigation and monitoring programs. There are various causes of internal corrosion but most often, through pipe failure analysis, the operator is able to determine the exact cause of corrosion. This paper examines how a facility piping program can identify segments prone to internal corrosion and establish effective monitoring and mitigations.
Artificial Neural Networks Ensemble Used for Pipeline Leak Detection Systems
Authors: Ferraz Inhau´ma N. , Garcia Ana C. B. , Bernardini Fla´via C.
Published: July 2009

The physical and operational properties of pipelines vary greatly. There is thus no universally applicable method, external or internal, which possesses all the features and the functionality required for a perfect leak detection performance. The authors of this paper know quite well that traditional methods, in a low uncertainty environment, overcome artificial intelligence methods of leak detection systems. If one considers the real world as a creator of uncertainties, neural networks and fuzzy systems emerge as important promising technologies for the development of leak detection systems. In this work, we propose a method for constructing ensembles of ANNs for pipeline leak detection. The results obtained in our experiments were satisfactory.
Overview of Tensile and Toughness Testing Protocols for Assessment of X100 Pipeline Girth Welds
Authors: Gianetto James A. , Bowker John T. , Dorling David V. , Taylor David , Horsley David , Fiore Susan R.
Published: July 2009

This paper provides an overview of research focused on the development and evaluation of guidelines for assessment of strength and toughness of pipeline girth welds. It also specifically presents results of a detailed mechanical and microstructural assessment for a series of rolled X100 girth welds, produced using advanced pipeline welding technologies and intended for strain-based designed applications.
Remnant Life Estimation of Pipelines With Internal Corrosion
Authors: Illson Tim , Ward Clive , Chauhan Vinod , Gardiner Michael
Published: July 2009

Situations can arise where the condition of a pipeline system is poorly known. This may be due to a variety of operational or commercial reasons. Failures will eventually occur if time dependent degradation mechanisms are active. While an appropriate response may be to inspect or hydrotest, this is generally not feasible within a short time frame and integrity assessments or replacements must therefore be prioritized. This paper looks at an ageing upstream pipeline system subject to internal corrosion. A case study is presented in which a system approaching its original design life is required to carry fluids from reservoirs now forecast to be productive for another 50 years. Fluids include sweet or sour gas, crude oil and injection water. Design data are available but inspection information is sparse with less than 10% of lines inspected by ILI; coupon data and well production forecasts are available. The challenge was to prioritize line replacements according to the remnant life of each pipeline, based on the limited available data. Current condition was measured for lines where ILI data were available. A corrosion risk assessment was conducted to identify credible degradation mechanisms. The pipelines were then grouped according to the fluids being transported. This enabled an estimate of current condition for all pipelines based upon the limited inspection and coupon data. In order to predict the remnant life it was necessary to estimate the future corrosion rates, again for all lines. A number of approaches could be used for estimating future corrosion rates. These include basing the rates on historical inspection data or using corrosion modeling techniques. The paper describes a hybrid method that synthesises these two approaches to allow a corrosion rate distribution to be postulated for calculating remnant life. In addition, the options for future corrosion rate estimation are described and the advantages and disadvantages of each one discussed.
An Upheaval Buckling Limit State Function for Onshore Natural Gas Pipelines
Authors: Matheson Ian , Zhou Wenxing , Zhou Joe , Gailing Rick
Published: July 2009

The reliability-based design and assessment (RBDA) methodology has gained increasing acceptance in the pipeline industry, largely due to a multi-year PRCI program aimed at establishing RBDA as a viable alternative for the design and assessment of onshore natural gas pipelines. A key limit state of buried pipelines that operate at elevated temperatures is upheaval buckling. The elevated temperatures generate large compressive axial forces that can cause Euler buckling susceptibility. The tendency to buckle is increased at vertical imperfections (i.e. a series of cold formed bends) that primarily occur due to topography. Upheaval buckling in itself is not an ultimate limit state but can lead to high strains, local buckling, high cycle fatigue, expensive remediation measures, and even loss of pressure integrity. The critical forces at which upheaval buckling occurs for typical hill-crest type imperfections present in onshore pipelines cannot be readily predicted using analytical methods. A parametric study is therefore undertaken using non-linear finite element analyses to generate a matrix of upheaval buckling responses. The critical force for the onset of upheaval buckling is then developed using a series of empirical relationships to capture the influences of all key parameters. An upheaval buckling limit state function is subsequently developed by comparing the critical buckling force with applied compressive force, which is a function of operating pressure and temperature differential between the operating and tie-in conditions. The limit state function can be readily implemented in a reliability analysis framework to calculate the pipeline failure probability due to upheaval buckling.
Manufacturing and Testing of Welded Stainless Steel Tubing: You Have a Choice Part 2—Feedwater Heater Tubing
Authors: Janikowski Daniel S. , Blessman Edward R.
Published: July 2009

The stainless steel feedwater heater specifications, ASTM A688/ASME SA 688 and ASTM A803/SA 803, were developed over 30 years ago. At that time, no one envisioned the temperatures and pressures that today’s super and ultra-critical units would operate. The increased pressures, temperatures, and expectations for reliability require special manufacturing techniques and testing for long tube life. The current ASTM/ASME specifications should be considered minimum requirements, and for long term reliability a number of additional special manufacturing processes and tests are essential. This paper summarizes many of the manufacturing and testing choices that should be specified to ensure high reliability. It identifies the advantages and disadvantages of each option and provides suggestions on what should be specified to ensure a reliable cost-effective feedwater heater tube for today’s applications.
Torsional Vibration of Turbine Generator Shafts Under the Disturbance of Electric Power System
Authors: He Qing , Du Dongmei
Published: July 2009

The torsional vibration of turbine-generator shafts can be excited by the disturbance of electric power system. The coupling interaction between the system disturbance and the torsional vibration makes turbine-generator oscillate. Alternate torsional stress due to large torsional vibration shortens the life of shafts, even makes shafts break. The natural characteristics and responses of torsional vibration of shafts of 200MW turbine-generator are simulated and analyzed under the catastrophic accidental condition. The causes for the breaking of bolts between the coupling of intermediate-pressure and low-pressure rotor and the coupling of generator and exciter rotor are discussed. The results are identical with the data recorded in the field.
Experimental Study on Effects of Slot Hot Blowing on Secondary Water Droplet Size and Water Film Thickness
Authors: Li Chunguo , Wang Xinjun , Cheng Daijing , Sun Bi
Published: July 2009

The effects of the slot hot blowing of the hollow stator blades on the size of secondary water droplets and the thickness of the water film were experimentally investigated in this paper. The experiment was carried out on the turbine blade cascades in a wet air tunnel with an inlet air wetness fraction of 7.9%, an outlet air velocity of 170m/s, a slot width of 1.0mm and a slot angle of 45° to blade surface. The Malvern Droplet and Particle Size Analyser was utilized to measure the secondary water droplet size and distribution downstream of the hollow stator blades in the experimental tests. The experimental results show that the maximum diameter and Sauter mean diameter of the secondary water droplets were reduced greatly and the water droplet size distribution became narrower. The larger blowing pressure difference resulted in the smaller secondary water droplets and the narrower water droplet size distributions. In addition, the efficiency of water separation from the hollow stator blade surfaces was higher for slot on the suction side than that of the pressure side case. Another simplified experimental test was also carried out on the flat plate to investigate the effect of slot hot blowing on the thickness of the water film downstream of the slot. The conductivity probes were used to measure the thickness of the water film downstream and upstream of the blowing slot. The results show that the slot hot blowing reduced the thickness of the water film downstream of the slot, which was affected by the blowing pressure difference and temperature difference between the hot blowing air and the main airflow. In conclusion, the slot hot blowing of the hollow stator blades has reduced the size of the secondary water droplets and secondarily has evaporated a little water film on the blade surfaces. Both effects are beneficial to reduce the erosion damage to the rotor blades.
A New Dual-Channel Analyzer for Vibration of Rotary Machine
Authors: He Qing , Du Dongmei
Published: July 2009

A new simultaneous sampling and analyzer for dual-channel signal of vibration for rotating machine is developed based on the C8051F060, which is a high-speed SoC system and has two ADCs embedded with high sampling frequency. The signal condition circuits for various vibration sensors are designed, such as charge amplifier, integral transform and rotating speed detector. A colorful TFT LCD used can display all kinds of vibration analysis plots that are friendly in human-machine interface. The large capability non-volatile memory is used to restore up to one hundred of group of vibration waves. With many typical functions of vibration analysis, including waveform analysis, spectrum, orbit and balancing, this instrument is widely applied to vibration measurement and fault diagnosis of machine and equipment, especially for field balancing of rotary machine.
GRDA Unit 2 Turbine Generator Control System Upgrade: A Case Study
Authors: Barney Charles J. , Kopczynski Jerry A.
Published: July 2009

Grand River Dam Authority (GRDA) operates a coal-fired electrical production power plant located thirty miles from Tulsa, Oklahoma. The facility contains two primary turbine-generators, referred to as Unit 1 and Unit 2. Each unit consists of a coal combustion boiler, a steam turbine, an electric generator, pollution control equipment, and auxiliary support equipment. Total maximum facility generating capacity for this plant is 1010 megawatts. ALSTOM Power was awarded a contract by GRDA to upgrade the obsolete control system for its Unit 2 turbine-generator during the fall 2007 outage. The scope included new steam turbine valves actuators, a 3-channel hydraulic safety system, electronic turbine control and protection systems, and a generator automatic voltage regulator, along with associated services and on-site training. Demolition, installation, commissioning and all performance tests had to be completed during a short 3-weeks schedule. The project is now complete; an obsolete control system was replaced with a more efficient, state-of-the-art control system. This paper will discuss and document details concerning this modernization control system.
Fouling of Heat Exchanger Tubes in Pulverized-Coal-Fired Combustion Chambers
Authors: Korytni Efim , Berman Yuli , Davidson Boris , Perelman Miron , Saveliev Roman , Bar-Ziv Ezra
Published: July 2009

Fouling is a major concern in coal-fired power plants caused by fly ash deposit on the heat exchanger tubes that decreases the overall heat transfer coefficient to water-steam mixture. Fouling has been characterized by weakly bound-loose form, which may be removed by various methods, such as soot-blowing, blast, and sand blowing. We have carried out experimental and modeling work on fouling to develop a methodology by which the thermal conductivity of the ash deposit would be determined in a way similar to the fouling process prevailing in real systems. For that we used tubes identical in material, diameter and temperature to those used in many utility boilers. In the experimental work we placed a tube in an axially symmetric 50 kW furnace, and tested fouling from three coals, bituminous and sub-bituminous. We also developed a dynamic model for the prediction of the ash deposition growth and its heat resistance. Comparison of the model prediction and experimental results yielded satisfactory fit. Consequently, thermal resistance of heat exchanger tuber with ash deposit of those coals was determined.
Renewable Generation Hazards and Risk
Authors: Cooper Terry
Published: July 2009

The paper will first address the difference between a hazard and a risk. With that as a basis, hazards associated with various types of renewable generation will be identified. Risk quantification and mitigation considerations will also be discussed.
Experience With On-Line Continuous Monitoring of Turbine Generator Stator and Rotor Windings
Authors: Stone G. , Lloyd B. , Sasic M.
Published: July 2009

Rotor flux monitoring and on-line partial discharge monitoring are well known tools that help plant owners to detect many developing rotor and stator winding problems in air and hydrogen cooled turbine generators. Both monitors are widely used by the utility industry. Most users periodically monitor the flux and PD using portable instrumentation that is connected to permanently installed sensors for a short period of time, usually once or twice per year. However, since 1994, continuous PD monitoring was commercially introduced, and shortly after, continuous flux monitoring started to be deployed. This paper will describe the continuous winding monitoring systems that are currently in use, and outlines the advantages and limitation of such systems. Case studies of the use of such continuous monitors will also be presented.
Retrofitting a Steam Power Cycle by Using Water From the Interstage Feed Water Pump as Reheat Spray
Authors: Saidi M. H. , Irani R. A. , Mousavi S. M. S.
Published: July 2009

Various methods are used in thermal power plants to adjust the superheated or reheated steam temperature to a pre-determined set point, including flue gas recirculation, using tilting burners and spray of water from discharge of feed water pump, etc. In this paper, an innovative method is presented to control the reheater temperature by tapping water from an interstage of the feed water pump to control reheater temperature at the Bisotoun Power Plant (a steam cycle based power plant in the western Iran). The spray water for the superheaters is secured from the discharge of feed water pump, but interstage water, instead of gas recirculation or using tilting burner, is used to control the reheater temperature. The total cycle is simulated with this arrangement and the results are compared with power plant actual data. Here, the variation of pump head and its power consumption is investigated as well. The tapped water requirement is calculated in terms of controlling reheat steam temperature at different loads.
The Successful Use of Surplus or “Gray Market” Equipment in Strategic Situations
Authors: Craigie Mike
Published: July 2009

The availability of ‘surplus’, cancelled order, or ‘advanced order’ equipment at attractive cost and almost immediate delivery, is a world-wide phenomenon which has surprisingly few restrictions on capacity.
A Dynamic Systems Model for Gasifier in IGCC
Authors: Aggarwal Mohit , Ydstie B. Erik , White Lee R.
Published: July 2009

We combine the concepts of element mole balance, population balance and shrinking core mechanism to develop a dynamic systems model for the Gasifier in an IGCC process. There is need for such a model for process analysis, optimization and low level control studies. The main idea is to use invariants, like elements (atoms), instead of compounds. This reduces the size of state space and we are able to explore the idea of a minimal state space representation for a thermodynamic process. The idea of a minimal state plays an important role in control theory as it is closely related to the concepts of controllability and observability.