bluuebunny/crossref_metadata_2025 huggingface dataset:
Data Management as the Foundation of Integrity Management
Authors: Choong Evelyn , Beets John
Published: October 2008

Worldwide, regulatory bodies are applying increasing pressure on pipeline operators to manage their pipeline systems in a safe and reliable manner. To respond to these escalating requirements, operators are developing comprehensive integrity management systems. Integrity management begins with developing strong data management capabilities to host and integrate numerous sources of physical data. A key issue in today’s integrity data management system development is integration of all pipeline data from multiple levels of the organization to one central location for easy and effective utilization of the information. Data are often scattered throughout the organization, which often tends towards data duplication, poor decisions, errors, and inefficiencies. The lack of an effective data management process leads to time and resource constrains. In the long run; development of a comprehensive integrated system has proven to be worth the investment. The primary objective of the data model is to account for a common/standard linear referencing of all pipeline features occurring along the pipeline route, and/or within the pipeline right of way. This paper describes the key factors to consider when developing a full data management system and provides some insights into how these integrated data are used to address the need for integrity management.
Strain-Based Design for Materials With HAZ Softening
Authors: Mohr William
Published: October 2008

Pipelines designed using strain-based design principles can place additional demands on the girth weld area to achieve the desired strain capacity. When girth welded, some modern higher-strength pipeline steels can have lower strengths in the heat-affected zone (HAZ) adjacent to the weld. The demands for strain capacity and toughness on these softer regions can be estimated, showing that for reasonable HAZ sizes, the demands are not much greater than without HAZ softening. Effects of internal pressure were explicitly considered. Softening appears to be particularly important for the pipes with the smallest wall thickness.
The Role of Technology in Preventing/Detecting Mechanical Damage
Authors: Hereth Mark , Leewis Keith , Gailing Rick
Published: October 2008

This paper is a state of the art review of technologies for preventing mechanical damage to pipelines. Technologies are presented in three categories, above ground, surface and below ground. There is a primer on each of the categories describing the fundamentals of the technology and the tools that can be applied by an operator. The primer for each category begins with a summary of the more familiar tools and progressing to emerging technologies. A standard format was chosen simplify presentation of information for each technology offering. The format included the following elements: • Description of the tool for prevention / detection, & mitigation, • Description of the sensor(s), • Reliability expectations, • Discrimination capabilities, • Sensor Range, • Stage of development in the R&D phases, • Cost filter as a beginning of the estimated cost/benefit value, and • Contact details with current government funding when available. There is a summary table with the same format to help in the selection of technologies.
On-Line Identification of Horizontal Two-Phase Flow Regimes Through Gabor Transform and Neural Network Processing
Authors: Selli Marcelo Fernando , Seleghim Paulo
Published: October 2008

The fundamental objective of this work is the construction of a specialist system capable of diagnosing different configurations of horizontal two-phase flow regimes. It is important to emphasize that the development of this know-how is capital to the efficient operation of facilities for manipulation and transportation of multiphase fluids, and represents today one of the most important challenges in petrochemical and thermonuclear industries. The working principle of the proposed system is based on the signals acquired by a rapid response pressure gradient sensor, and on its post processing through Gabor Transform and on a previously trained artificial neural network. The implementation is accomplished in way that the diagnosis operation is performed on-line, from acquisition of the signal to its post-processing. Experimental results were obtained on the experimental circuit at NETeF — Nu´cleo de Engenharia Te´rmica e Fluidos of USP — Universidade de Sa˜o Paulo, at Sa˜o Carlos, using a horizontal test section, with 12m length and 30mm internal diameter. Experiments were done with the following air-water flow regimes: stratified smooth, stratified wavy, intermittent, annular and bubbly. Results show that the percentage of correct flow regime diagnosis in steady state conditions is practically of 100%.
Utilizing Low Level Videography and GIS to Rethink Traditional Phase I Environmental Site Assessments
Authors: Miller Mary L. , Shankland Cameron
Published: October 2008

The method used for traditional “Phase I” Environmental Site Assessments (ESA’s) has required staff to physically walk the rights-of-way (ROW). In order to compete the ESA in a more timely and cost-effective manner than traditional techniques allowed, URS Corporation (URS) contracted LinearVision (LV) to fly the utility ROW and collect low-level, airborne, geo-referenced videography, complemented with geo-referenced still-imagery to enable URS to complete the Phase I ESA data analysis in their office. The data provided enabled URS’s analysts the ability to access all ROW points of interest in their Geographic Information System (GIS), and “fly” the line with oblique and downward perspectives from their computer screen. The digital video could be sped up or slowed down allowing URS the ability to review each frame for careful, detailed analysis, and identify potential recognized environmental conditions (RECs) and encroachment upon the ROW. The high-resolution still-imagery provided URS the ability to zoom into the potential REC for a closer inspection of site features, vegetation, and surrounding land use. URS created a database of potential RECs and areas of interest along with a simple user interface as a deliverable to the client, which allows the user to link directly to specific video frames and high-resolution photographs for their own review and analysis. The cost of the airborne data capture and processing was substantially less than a traditional Phase I ESA. Furthermore, the video and high-resolution images provided for a more comprehensive analysis tool, which can be reviewed by multiple analysts and catalogued for future reference by third parties. An additional benefit is that the high-resolution photographs can be imported into AutoCAD or other software for development of maps and figures. Overall, the net result of low-level GIS integrated videography is enhanced quality of data and a 50% reduction in total cost for the ROW project as compared to traditional Phase I ESA methodology.
Automatic Weld Bead Recognition and Defect Detection in Pipeline Radiographs
Authors: Felisberto Marcelo K. , Schneider Guilherme A. , Centeno Tania M. , de Arruda Lucia V. R.
Published: October 2008

The current work contributes to the research in the area of pipelines non-destructive testing by presenting new methodologies for the automatic analysis of welds radiographs. Object recognition techniques based on genetic algorithms were used for the automatic weld bead detection. In addiction, we developed an image digital filter for the detection of defects in the weld bead zone. These methodologies were tested for 120 digital radiographs from carbon steel pipeline welded joints. These images were acquired by a storage phosphor system using double-wall radiographic exposing technique with single-wall radiographic viewing, according to the ASME V code. As a result, even defects that are hard to be detected by human vision are automatically highlighted and extracted from the whole image to be classified in the further stages of the weld inspection process.
Leading Practices for the Prevention of Mechanical Damage
Authors: Hereth Mark , Selig Bernd , Zurcher John , Leewis Keith , Gailing Rick
Published: October 2008

Practices that are used by pipeline operators to prevent mechanical damage are examined in this paper. A set of practices specific to pipeline operations is presented. The practices were initially developed by a group of subject matter experts working under the auspices of the American Petroleum Institute and the Association of Oil Pipelines (API/AOPL) Performance Excellence Team. The practices drew upon the work started within the Common Ground Initiative in the late 1990s and continued by the Common Ground Alliance. The practices presented were reviewed again in preparation of this report. The practices build upon practices defined by Common Ground Alliance (CGA), largely by providing greater specificity and ensuring completeness and follow through in communication and documentation. A subset of these practices became the foundation of the standard, API 1166 Excavation Monitoring and Observation. The paper also provides an overview of historical safety performance for the period 1995 through 2003; with a specific focus on mechanical damage related incidents including the additional detail available in the recent change in Pipeline and Hazardous Materials Safety Administration (PHMSA, US-DOT) Incident Reporting. This period was selected because it represented the time period where there was a heightened interest in preventing damage to pipelines as described above. The large majority of mechanical damage related incidents result in an immediate impact; a small portion occur at some later point in time. Data for the nine-year period indicate that approximately 90 percent of the incidents result in an immediate impact. This is significant in that it underscores the importance of prevention of damage. The experience of hazardous liquid pipelines has shown a continuing decrease in numbers of annual incidents. The experience of natural gas pipelines has not shown a decreasing trend; in fact, it is relatively flat for the period of study. While the heightened awareness and strong commitment to dedication are known to have had an impact on damage prevention through numerous stories and vast experience shared by a variety of stakeholders, it is prudent to be concerned that the performance may be reaching a “plateau”.
Performance Testing of a Multi-Component Powder Coating System
Authors: Been Jenny , Given Russ , Worthingham Robert
Published: October 2008

A number of new coatings offer the possibility for cost savings and/or improved performance. As a shielding coating, the resistance of a high-integrity three-layer coating to disbondment in damaged areas and as a function of applied cathodic potential is of interest with regard to the creation of an environment on the pipe that will support corrosion and/or cracking. The cathodic disbondment (CD) behavior of a multi-component powder coating system has been characterized under simulated field conditions (restrictive mass transport using soils), rather than the standard CSA protocol. The as-received coating displayed excellent impedance properties and minimal disbondment under normal operating conditions. Coated panels were furthermore subjected to impact damage and a hot water soak prior to the CD tests. Results showed minimal disbondment of the multi-component powder coating system over 3 to 6 months regardless of impact damage or temperature. There was some evidence that more negative potentials may increase the disbondment area over longer periods of time. However, mechanistic considerations, literature information, experimental observations and field experiences would suggest that coating disbondment might be limited when the coating is properly applied and otherwise in good condition. Longer-term experiments are required to confirm the presence of a maximum size disbondment.
An Overview of Environmental Issues Pertaining to Abandonment of an NEB-Regulated Pipeline: A Case Study of the Yukon Pipelines Limited Abandonment
Authors: Roblin Katherine E.
Published: October 2008

The National Energy Board (NEB or the Board) is an independent regulatory tribunal that regulates various aspects of the Canadian energy industry, including the design, construction, operation and abandonment of oil and gas pipelines that cross provincial or international borders. Under section 74(1)(d) of the National Energy Board Act, a company shall not, without the leave of the Board, abandon the operation of a pipeline. To date, only one large-scale abandonment of an NEB-regulated pipeline has occurred. However, as pipeline infrastructure ages and markets shift, pipeline abandonments are likely to become more common. It is therefore important to review and learn from this case so that industry and regulators may effect future abandonments in as efficient and environmentally responsible a manner as possible. The Yukon Pipeline was part of the Canol Pipeline built by the United States Army in 1942. From 1958 through 1994, Yukon Pipelines Limited (YPL) and related companies operated the portion of pipeline from Skagway, Alaska, to Whitehorse, Yukon, to transport furnace oil, diesel fuel and gasoline to Whitehorse for distribution and use in the Yukon. The 114 km Canadian portion of the Yukon Pipeline, as well as an associated pump station at Carcross, Yukon, and a tank farm in Whitehorse, have been regulated by the NEB since 1962. An abandonment hearing was held in 1996, and the NEB issued a conditional order granting YPL leave to abandon the pipeline. The order would not come into force until YPL conducted further contaminant investigation and planned and successfully completed remedial work, all in consultation with a variety of stakeholders and regulatory bodies. The physical abandonment of the YPL facilities was relatively straightforward. Significant issues pertain primarily to the ongoing associated remediation of historical contamination. Challenges include appropriate characterization of the site, changing environmental standards and regulatory frameworks, changes in approach to remediation of the site, and complex jurisdictional interactions. Special concerns pertain to the application of environmental risk assessment and risk management. In order for future abandonment projects to proceed efficiently and effectively, it is recommended that site characterization and risk assessment work be completed early in the process, that risk management planning also be completed as early as possible (including planning how site closure will be achieved within the applicable regulatory context), and that the abandonment process and provisions be sufficiently flexible to accommodate changing circumstances while still achieving the desired end result.
Optimizing Bell Hole Examinations for Early Generation Pipelines
Authors: Amend William E.
Published: October 2008

The absence of reliable historical information about a pipeline together with the presence of unique vulnerabilities makes integrity management of early generation pipelines a challenge. Bell hole inspections, often referred to as “direct examinations” often represent unique opportunities to learn valuable information about pipelines for which historical information is limited. The paper describes how bell hole inspections can contribute to an improved understanding of the integrity of early generation pipelines. There are two objectives for this paper: 1. Provide background information related to early pipeline materials, construction, and inspection practices to help inspectors and integrity assessment personnel interpret what they have found during the course of their inspections. 2. Describe supplemental observations, inspections, and measurements that are useful when inspecting early generation pipelines, and The paper includes a summary of early generation pipeline materials and construction practices as a basis for interpretation of features observed during bell hole inspections. Pipe surface features which are characteristic of various manufacturing or fabrication processes and which potentially impact pipeline integrity are illustrated. Nondestructive examination methods, and their role in evaluating flaws and pipe properties specific to early generation pipelines are described.
Development of a Pipeline Surface Loading Screening Process
Authors: Warman David J. , Chorney Jules , Reed Mike , Hart James D.
Published: October 2008

Pipeline Operators receive numerous requests annually to cross their pipelines. In many of these cases detailed analysis using a number of different methods are performed since no simplified approach is available. The Canadian Energy Pipeline Association (CEPA) with Kiefner and Associates, Inc. undertook the development of a screening methodology for vehicle loading. The hope is a standard approach to these analyses might be established to assist pipeline operating companies. This paper describes an approach detailing the development and implementation of a simplified screening process to assess the effects of surface loads on buried pipelines. A design basis was established based on a literature review to identify theoretical models, standards, codes, and recommended practices that are currently used to assess the surface loading effects on buried pipelines. This design basis was incorporated into a methodology utilized to develop a screening tool which provides a simple “pass/no pass” determination and is based on attributes which are generally easy to obtain (e.g., wheel or axle load, ground surface loading pressure, depth of cover, maximum allowable operating pressure and design factor). Situations which pass the initial screening would require no additional analysis while situations that do not pass the initial screening may need to be evaluated on a more detailed basis. Simplified graphs have been developed to assist in additional screening prior to performing a more detailed evaluation.
Managing GIS and Spatial Data to Support Effective Decision Making Throughout the Pipeline Lifecycle
Authors: van Wyngaarden Robert , VanderWal Mel
Published: October 2008

Many pipeline industry managers and senior officials intuitively understand that location is important to most aspects related to pipelines throughout the life-cycle — from project concept, through construction and operations and finally to decommissioning. However, many organizations are not taking full advantage of location as being a vital component to support business decision-making across the entire range of activities undertaken by pipeline companies. A Geographic Information System (GIS) is a tool that takes advantage of geography. GIS is ideally suited for the storage, display, and output of geographic data, and moreover, the analysis and modeling of geographic data. While GIS has been around as a technology for over 30 years it is only in the last several years that it has started to be extensively used within the pipeline industry. Most managers have heard about GIS. Many organizations have already started to implement GIS and CAD-based solutions through individual projects and with a technical focus of automating work flows or business processes such as generating alignment sheets, regulatory compliance, integrity management, and land management to name a few. Given that many of these applications tend to be stand-alone or isolated developments, pipeline companies need to look at the complete spatial environment of all potential tools and applications, and support this with a vision of a common spatial data warehouse in a holistic sense. Any company that embraces a continuous gathering of spatial data throughout the pipeline life-cyle will have a significant knowledge base whose value will increase over time. A spatial data warehouse of truly integrated environmental, engineering and socioeconomic factors related to a pipeline during the entire lifecycle will have a total value that transcends the value of the individual factors. The Return on Investment (ROI) of a properly developed GIS framework and spatial data warehouse looking at all operational demands and support applications will certainly be many times over the original expenditure as measured in cost savings as well as better decision making. This paper will present insights and approaches into how to properly and effectively leverage the spatial data asset and in deploying GIS throughout the enterprise. These include addressing all of the elements that are key in implementing GIS — hardware, software, data, people and methods — as well as considering some of the ROI and value-based measures for GIS success.
Securing Pipeline Approvals in a Tough Regulatory Environment
Authors: Buszynski Mario E.
Published: October 2008

The Regional Municipality of York is located immediately north of the City of Toronto. It is the fastest growing municipality in Ontario. The rapid expansion of residential, industrial and commercial development in the municipality has led to a weakness in the electrical and gas infrastructure. The Ontario Power Authority (the agency responsible for managing the power requirements in the Province of Ontario) has recognized this weakness and has developed plans calling for a new gas-fired generating station and improvements to the electrical grid. The shortages of gas supply and electricity have not developed overnight. Hydro One, which runs the electrical grid, initiated a supply study in 2002. The study recommended upgrading a 115 kV transmission line to a double circuit 230 kV transmission line on the existing corridor. The ensuing public outcry resulted in the municipality passing a resolution against the upgrade. Similarly, a large gas-fired generating station proposal was abandoned as the result of citizen opposition. In 2003, the Ontario Energy Board approved new Environmental Guidelines for the Location, Construction and Operation of Hydrocarbon Pipelines and Facilities in Ontario. The guidelines include specific new requirements for planning pipelines in urban areas. Among other things, these requirements involve the identification of indirectly affected landowners and a more detailed analysis of public issues and how they were resolved. It became clear that in order to achieve regulatory success, not only would the public have to become actively engaged in the decision-making early in the process, the technical reviewers (federal, provincial and municipal agencies) would likewise have to be actively involved. Through the use of two case studies of proposed large-diameter natural gas pipelines initiated in York Region in 2005, this paper describes the techniques used to engage the public and the regulators. It also describes how the public involvement requirements contained in the Ontario Energy Board’s new guidelines were incorporated into the planning process. The case studies begin with a rationale for the study area selected. A description of issues follows. The techniques used to address these issues and the success of the program are documented. Techniques include face-to-face project initiation meetings, use of technical and citizens’ advisory committees, sub-committee meetings to resolve specific issues and site-specific field work. The study results illustrate that it is possible to plan a right-of-way in such a manner as to satisfy the general public and regulators, be compatible with existing development, conform to the new Ontario Energy Board guidelines and minimize the amount of remedial work required to mitigate the impacts occurring on and adjacent to the right-of-way.
Analysis of Girth Welds in Pipelines Subjected to Lifting Loads
Authors: Alexander Chris , Scrivner Ron
Published: October 2008

Williams Gas Pipeline requested that Stress Engineering Services provide engineering services to analytically assess issues that occurred in a 30-inch pipeline due to cracked girth welds. The focus of the analytical effort was to simulate the lifting during the pipeline construction process. Using finite element methods, nominal bending stresses were calculated considering a specific set of criteria including 80-foot pipe joints, skid locations, and a given root pass weld thickness. These bending stresses were used to calculate a total stress that included stress concentration factors (SCFs) due to hi-low weld mismatch and weld profile geometry. For conservatism, residual stresses were also included in computing the total stress. As an example, the results showed that if a residual stress of 50 percent yield and a total SCF of 4.5 are assumed, the lift height should be limited to approximately 9 inches for a root pass weld thickness of 0.0625 inches. In this calculation, a stress limit of two times yield was used. Once the final stress was computed considering the range of variables, a closed-form equation was developed that integrated the variables of interest for the 30-inch pipe. This equation was used to compute data points to guide Williams in establishing permissible lift heights for a range of SCFs for the welds. A stress limit of two times the yield strength was selected as the limiting value. The details of the work presented in this paper will assist pipeline operators in developing a protocol that balances the need for rapid construction and ensuring that proper girth welds are fabricated.
Assessing the Use of Composite Materials in Repairing Mechanical Damage in Transmission Pipelines
Authors: Alexander Chris , Worth Franz
Published: October 2008

Mechanical damage involving dents with gouges is one of the leading causes of transmission pipeline failures in terms of both static and cyclic pressure loading. Because of the severity of this defect type, pipeline companies are required to respond to these anomalies by either removing damaged sections or repair using welded sleeves. For more than 10 years, composite materials have been used to repair corroded pipelines and their use has gained wide acceptance across the pipeline industry. Numerous systems have been tested with results being presented in the open literature. Testing was recently performed to assess the use of a water-activated composite repair system, Aquawrap®, in terms of its ability to repair mechanical damage subjected to cyclic pressure service. The Aquawrap® repair system has been extensively tested on corrosion defects but testing on pipes with dents had not been done. The water activated pre-preg urethane resin system offers excellent long tern (creep-rupture) strength combined with easy low cost field installation. Pipes having diameter to wall thickness ratios ranging from 34 to 68 were fitted with dents and gouges. Repair involved removing the gouged material of the pipe after indentation and repairing using the composite sleeve. The result of this specific test program showed that on-average the fatigue life for mechanically-damaged pipes can be increased on the order of three orders of magnitude when repaired by grinding and installing composite sleeves. This paper provides details on the methodology of the test program, results, and most importantly, information that can be used by operators in repairing their pipeline systems.
Reinforcing Field Fabricated Branch Connections Using Composite Materials
Authors: Alexander Chris , Wilson Tony
Published: October 2008

Field fabricated branch connections are manufactured in lieu of forged tee fittings. To be used in accordance with ASME B31.8, these connections are subject to the area replacement method to ensure that sufficient material is present to reinforce the opening in the run piping. If insufficient material is present in the weld itself, pads are welded into place to serve as the reinforcing mechanism. One question posed recently to Stress Engineering Services, Inc. and Armor Plate, Inc. by a gas pipeline company was the feasibility of using composite materials to reinforce previously-fabricated branch connections that did not have sufficient steel material present to satisfy the requirements of the area replacement method. Initial evaluation of the concept involved calculating the strength required to ensure that the branch connection would have sufficient long-term strength to withstand operating condition. Elastic-plastic finite element analyses were also performed using limit analysis methods to determine the minimum composite thickness that was required. Once all analytical efforts were completed, a full-scale test was performed on an exemplar branch connection fabricated from a 24-in × 0.375-in pipe and a branch pipe fabricated from 12.75-in × 0.375-in pipe (both Grade X42). Pressure levels exceeding 2.9 times the MAOP of the 24-inch pipe (787 psi) were reached before the branch connection leaked at a maximum pressure level of 2,314 psi. This burst pressure is 1.76 times SMYS. A burst in the connection did not occur, but rather a leak developed in the weld joining the branch and the run pipes and most likely initiated in the crotch region where the highest levels of strain occurred during pressure testing. Considering the results of the test program and the calculated results, the pipeline operator concluded that a sufficient design margin existed to warrant the use of the composite materials as a valid reinforcement method. In addition to specific elements of the evaluation program, this paper will also provide discussions on using composites materials in repairing and reinforcing high pressure pipelines.
State of the Art Assessment of Composite Systems Used to Repair Transmission Pipelines
Authors: Alexander Chris , Francini Bob
Published: October 2008

For the past decade there has been relatively wide acceptance in using composite materials to repair damaged gas and liquid transmission pipelines. There have been numerous independent research programs performed by pipeline companies, research organizations, and manufacturers that have contributed to the acceptance of composites as a legitimate repair material. Additionally, insights have been gained by both pipeline operators and composite repair manufacturers during field installations. ASME has also responded by adding sections to both the ASME B31.4 and B31.8 pipeline codes, as well as currently developing a repair standard for non-metallic composite repair systems by the Post Construction Committee. Stress Engineering Services, Inc. and Kiefner & Associates, Inc. have been integrally involved in assessing the repair of pipeline systems, with the former having been involved in performing full-scale testing and analysis on most of the major U.S.-based composite repair systems. The purpose of this paper is to provide for the pipeline industry a third-party evaluation of composite repair systems and information that is needed to properly evaluate how composite materials should be used to repair high pressure pipelines. The contents of the paper will include discussions on what critical elements should be evaluated for each composite system, items of caution and concern, and the importance of evaluation to ensure safe long-term performance.
Residual Stress and Stress Corrosion Cracking of High Pressure Hydrocarbon Transmission Pipelines
Authors: Van Boven Greg , Rogge Ronald , Chen Weixing
Published: October 2008

Stress corrosion cracking (SCC) can occur on the exterior surface of high pressure hydrocarbon transmission pipelines fabricated from low carbon steels. Both the initiation of SCC and the ability of SCC to progressively increase in depth is a complex and poorly understood phenomena. Previous empirical evidence suggests that residual stresses may be involved in this initiation and growth process. This paper describes a laboratory research project designed to investigate the correlation between residual stress and SCC. In this project, tensile test specimens with increasing levels of compressive and tensile residual stress on the surface and through the thickness of the specimen were fabricated. These stresses were sufficiently large as to dominate the other slight variations in material properties that may occur on identically formed test specimens. The residual stresses were then mapped across the length and through the depth of the specimens by a non-destructive neutron diffraction technique. A SCC initiation process was applied to the specimens. It was found that the formation of micro-pitting, to a depth up to 200 μm, occurred preferentially in areas where tensile residual stresses were the highest (about 300 MPa). Initiation of SCC, although found all at the bottom of this micro-pitting, occurred with a 71% normalized frequency in locations where the surface residual stress was in the range of 150 MPa to 200 MPa. Experimental data revealed that cracks generated in near-neutral pH environments can be readily blunted, due to both plastic deformation (room temperature creep) and extensive dissolution. As a result, a high positive tensile residual stress gradient is necessary for developing cracks in pipeline steels exposed to near-neutral pH environments. The tensile residual stress represents a large mechanical driving force for initial crack nucleation and short crack growth. Active cracks may become dormant as the near-surface residual stress gradient changes from a high to a low tensile stress or if the stress becomes compressive due to self-equilibration through the wall thickness direction. Special conditions may exist in pipeline steels where crack dormancy may not occur within a short distance to the surface, which may include, for example, the presence of a large tensile residual stress gradient over a longer distance, particular microstructures conducive to galvanic corrosion, and special environmental conditions susceptible to hydrogen-induced cracking.
Probabilistic Assessment of a 70-Year Old Pipeline Subject to Seismic Deformation
Authors: Warke Robert W. , Hart James D. , Thacker Ben H.
Published: October 2008

This paper presents an assessment case study on several segments of buried natural gas pipeline constructed in 1936 with ‘bell-bell-chill ring’ (BBCR) style girth weld joints, and currently operating in a seismically active region of North America. Seismic vulnerability was evaluated in terms of girth weld fracture and plastic collapse probabilities for specified hazards of varying severity and likelihood. Monte Carlo simulations performed in NESSUS® provided failure probability estimates from distributed inputs based on PIPLIN deformation analyses, nondestructive and destructive flaw sizing, residual stress measurements, weld metal tensile and CTOD tests, and limit state functions based on published stress intensity and collapse solutions.
Low-Constraint Testing of Pipeline Girth Welds
Authors: Rudland D. , Wang Y.
Published: October 2008

Conventional fracture toughness test specimens have high crack-tip constraint. Defects in pipelines are typically under low constraint conditions. Assessment of the pipeline defects using the fracture toughness of the conventional test specimens can be overly conservative. This paper presents a novel low-constraint test configuration termed back-bend test to measure the toughness of pipeline girth welds. Full transition curve tests were conducted with both weld centerline and HAZ notched specimens. The test setup, instrumentation, and data analysis are described in the paper. The crack initiation transition temperature results for an X70 and X100 linepipe steel girth weld and heat affected zone are presented and discussed.
An Updated Cooling Rate and Microstructure Model for Pipeline In-Service Hot-Tap Welds
Authors: Chen Yaoshan , Wang Yong-Yi , Horsley David
Published: October 2008

This paper describes an improved numerical model for the predictions of cooling rate and heat-affected-zone (HAZ) hardness for welding onto an in-service pipeline. Compared to the current PRCI thermal analysis software, the improvements in this new model include a new mesh generator for the heat transfer finite element procedure and a dynamically-coupled microstructure model that features a state-of-the-art phase transformation and hardness calculation algorithms. The new mesh generator is capable of producing finer mesh than that in the current PRCI thermal analysis software, particularly in the HAZ region so more accurate temperature field can be captured for the hardness calculation. To validate the implementation of these improvements in the model, previous measurements by Battelle and EWI have been collected and compared to the predicted results by the new model. These measurements include cooling times from 800°C to 500°C (t8/5) for both sleeve and branch configurations, and hardness in the HAZ for some of the sleeve configurations.
Stress Analysis of Surface Pipelines Located in Regions of Differential Ground Movements
Authors: Deng Kam , Queen David J. , Felber Andreas , Bergman Don W.
Published: October 2008

Buried pipelines running through areas of large differential ground movements, such as active landslides, can be subject to severe overstress conditions. Moving these pipelines to the surface (i.e. surfacing) and resting them on timber skids reduces the impact of ground movements because slippage can occur between the pipe and the skids. This approach has been used successfully on several pipelines. Surfacing was recently considered for a 4.5 km section of a buried pipeline situated in northern British Columbia. The surfaced pipeline is supported by timber skids every 2 m and winds through mountainous terrain containing twenty different movement zones in which differential displacements range from 0 m to 3 m. Along the route, the direction of the ground movement varied with the terrain. The alignment also crossed a creek with a 45 m clear span. This paper describes the methodology used in completing the stress analysis for the surfaced pipeline. To capture various load effects, an existing construction stage analysis program was modified to facilitate the modelling of the surface pipeline under the various load paths. The evolution of the displacement and stress state of the pipeline was determined and tracked for several different load paths. For each state, a single plot that summarized the ground movement, slip distances, skid reactions and pipe stresses was produced. The results from this analysis are used to discuss the response of surface pipelines under thermal and ground movement loads.
Data Is an Asset That Should Be Managed
Authors: Adam Steve , Hlady Joseph T.
Published: October 2008

Engineering data is often collected for a single purpose and then lost, corrupted, duplicated, or simply not accessible to all who may want to use it. The value of data often goes beyond its purchase and the result of the intended purpose. Access, security, and further leveraging data are but a few advantages to keeping data safe and sharing it. Furthermore, the amount of data on any project or within an enterprise will continue to grow at an alarming rate, hence the need for shifting our perception of data from expenditure to asset. Using methods such as Net Present Value, Return on Asset, and pay back, this paper will illustrate how data can be viewed as an asset rather than an expenditure. These valuations are not intended as accounting strategies, merely methods to illustrate how data shows asset characteristics. Ultimately, when data is seen as an asset, it is treated as such and stored and maintained in an information management system.
Computational Simulation of Line-Pipe Fabrication Processes
Authors: Dong P. , Hong J. K. , Leis B. N. , Lopez P. S. , Chavela R. G. , Ghenno C. S.
Published: October 2008

Line pipe fabrication involves plate forming and seam welding, for which the forming process is continuous for some processes. Residual stresses that are important in line pipe performance, particularly for sour service, reflect the interaction between the plate forming, radial expansion, and welding-induced thermal and local plastic deformation. These mechanisms interact to produce a complex three-dimensional residual stress field. This paper uses an advanced computational simulation procedure to simulate the detailed forming and welding interactions and their combined effects on thermal and residual stress development. Such technology can be used to guide fabrication procedures and optimize radial expansion as well as welding parameters, which more typically reflect trial and error type decisions. The simulation process is first outlined and then applied to a specific pipe diameter and wall thickness ratio. Detailed three-dimensional finite-element-based simulations of the spiral seam welding process are then presented considering both plate forming/radial expansion effects and their interactions with seam welding. Validation experiments are presented whereby simulation outputs are directly compared to measured data. Finally, use of pipe split-ring testing is simulated to evaluate its ability to quantify the residual stresses. Not surprisingly, such results show steep through-wall gradients in the hoop and axial components, with levels for some components well above the yield stress. Cold expansion is shown to be beneficial in terms of relief of the hoop component, but potentially detrimental for the longitudinal weld component. Pipe parameters like diameter to thickness and grade are considered. The utility of split-ring testing is evaluated analytically, and compared to typical results for expanded line pipe.
Real Time Data Integration Based on the GIS Pipeline Infrastructure for the Management of the Gas and Power Business
Authors: Salcedo Fernando Jose´ de Carvalho , de Carvalho Ronaldo Jose´ Seixas
Published: October 2008

The Strategic Data and Information Management (GEDI, as per Portuguese initials) in PETROBRAS (Brazilian oil company - Gas & Power Business Unit), has as its main process to turn available the most correct and updated information to the related user, using the adequate means to access and capture of data, coming from a variety of sources, in order to add strategic value to business. The SCADA system (Supervisory Control And Data Acquisition) integrates the facilities of thermo electrical plant and pipeline with the field, including operational stations, measurements and energy deliveries. The Geographical Information Systems (GIS) allows the use of maps to visualize the geopolitics aspects, gas pipeline infrastructure and satellite images. The historical data systems has as its requirements, the interface among many SCADA systems, through the tracking of historical data, common process variables real time data (flow, pressure, temperature, etc.) and KPI’s visualization (typical performance indicators of energy systems such as unavailability, generation efficiency, distribution, etc.). Based on the business systemic vision, the Real-Time Enterprise Architecture (real time data integration and performance indicators based on the GIS software platform ) was developed for PETROBRAS, Gas & Power Business Unit (GPBU) enterprise scenario. The present work has its focus in the real time visualization of integrated data, coming from gas pipelines and thermo electrical plants GIS infra-structure, guaranteeing the integrity, the audit trail of information and a proactive vision for the GPBU management.
A Comparison of Inherent Risk Levels in ASME B31.8 and UK Gas Pipeline Design Codes
Authors: Goodfellow Graham , Haswell Jane
Published: October 2008

The approach to gas pipeline risk and integrity management in the US, involving the development of integrity management plans for High Consequence Areas (HCA), is usually qualitative, as outlined in ASME B31.8S. Depending on the engineering judgement of the assessment team this can lead to a wide variety of results making risk comparison between pipelines difficult. Qualitative risk ranking methods are popular in Europe, but quantitative risk assessment (QRA) is also used for setting acceptable risk levels and as an input to risk and integrity management planning. It is possible to use quantitative risk assessment methods to compare the levels of risk inherent in different pipeline design codes. This paper discusses the use of pipeline quantitative risk assessment methods to analyse pipelines designed to ASME B31.8 and UK IGE/TD/1 (equivalent to PD 8010, published by BSI, for the design of gas pipelines) codes. The QRA utilises predictive models for consequence assessment, e.g. pipeline blowdown and thermal radiation effects, and failure frequency, in determining the risk levels due to an operational pipeline. The results of the analysis illustrate how the risk levels inherent in the two codes compare for different class locations & minimum housing separation distances. The impact of code requirements on design factor, depth of burial, population density and the impact of third party activity on overall risk levels are also discussed.
Considerations for Choosing a Remote Monitoring System for Cathodic Protection Rectifiers
Authors: Charlebois Paul , Slevin Rob
Published: October 2008

When choosing a remote monitoring system for your cathodic protection rectifiers there are many things to consider such as: do you want the ability to poll and control your rectifiers’ output or are you looking for an inexpensive system to satisfy code requirements [1]? Do you have an existing radio network or will you have to rely on an outside service provider? These are only some of the many questions that require answers before a decision can be made as to which of the many remote monitoring systems available is best suited for your cathodic protection monitoring program. This paper examines many of the questions that need to be answered prior to choosing a remote monitoring system and also discusses the pros and cons of the many options available to the industry. This will allow the reader to make informed decisions when choosing a remote monitoring system and hopefully avoid the costly mistake of installing a system that does not meet your requirements now and in the future.
Considerations for Training Simulations of Liquid Pipelines
Authors: Christie Brett , Norris David
Published: October 2008

The use of integrated offline training simulators within the liquids pipeline community has not been widespread. Some companies opt to use a stand-alone generic pipeline simulation, which has advantages of ease of set up and offer relatively lower capital cost. They can also be effective in training on basic hydraulics under both normal and abnormal operating conditions. However, since they do not train on the actual pipeline system of the company, trainees do not learn any of the specifics of their company’s pipeline. Also, if the system is not interfaced to the pipeline SCADA system, trainees may have difficulty transferring what they have learned into their day to day control of the pipeline. This paper outlines the major considerations for ensuring that the offline training environment is as a realistic depiction of the actual pipeline control center as possible. Techniques and guidelines, such as Gap analyses, cause & effect diagrams, and flow charts are presented.