bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Rational Design and Operating Strategy for Pipelines Traversing Unstable Slopes
Authors: Simmonds Gordon R. , Zhou Z. Joe , Samchek Alan T. 
Published: October 2016

A common challenge for pipeline designers is the placement and safe operation of pipelines within unstable slopes. Consequently, special design and operation procedures must be created to maintain the integrity of the pipeline through its operating life. Nova Gas Transmission Limited (NGTL) has developed a methodology to monitor pipeline integrity in slow moving (creeping) unstable slopes.
This methodology uses Pipeline-Soil Interaction models to produce parameters that are in turn placed in Pipeline Integrity Assessment Techniques such as finite element analysis. For slope movements, pipeline integrity is based on pipeline strain criteria that are established from regulated codes or NGTL’s risk-based criteria. The result is that pipe strain can be estimated over time given a particular soil type and predicted ground movement.
The ability to predict when a pipeline is reaching a critical strain allows NGTL to effectively quantify the risk and associated cost for various remedial measures based on a given operating life (life-cycle cost). These remedial measures can take the form of strain relieving outages, re-routing of the pipeline, directional drilling, or conventional geotechnical remedial practices (dewatering, slope grading, buttressing, etc.). Two case studies are presented detailing this present state-of-practice methodology at NGTL.
The Alberta Pipeline Environmental Steering Committee: A Model for Cooperative Resolution of Issues
Authors: Brocke Larry K. , Kuipers Fred 
Published: October 2016

In the past, industry and government independently conducted research and gathered information to address environmental issues. The results were not always mutually accepted.
A number of emerging environmental issues arose in the mid 1980’s that demanded mutual resolution. As a result, the Alberta Pipeline Environmental Steering Committee was established in 1988.
The Committee initially consisted of industry and government representatives. The membership has since been increased to include landowner representation, local government, federal interests and contractors.
The Committee has four main purposes:
1. To assist government, industry and other interest groups in their pursuit of environmental protection and economical pipeline planning, construction, operation, abandonment and reclamation in Alberta;
2. To act as a vehicle for government to receive input from industry and other interest groups during policy formation;
3. To identify, prioritize and make recommendations for workable solutions on Alberta pipeline environmental issues and;
4. To help implement recommendations by organizations represented on the Committee.
The benefits of this model are agreement on issue identification and mutual resolution. The success of the model has resulted in it being adopted for other sectors as well.
Preparing for New Modes of Pipeline Operation in the People’s Republic of China
Authors: Dahai Chang , Wike Andrew 
Published: October 2016

There are more than 7,000km of crude oil transmission pipelines, and more than 8,000km of natural gas transmission pipelines in the People’s Republic of China. Although there are few product pipelines in China today, the growth of this industry is anticipated, fueled by the rapid development of the economy in China.
The China Petroleum Pipeline Bureau is the largest pipeline operator in China, accounting for more than 6,000km of crude oil and natural gas pipelines. The Langfang-based Staff and Workers College (known simply as the Pipeline College) is a unit of the China Petroleum Pipeline Bureau. Students at the Pipeline College include full-time engineering students, and short-term trainees. In general, the short-term trainees are management and operator level staff who attend the Pipeline College for more advanced training. Having a lack of effective training tools, it was almost impossible for the Pipeline College to provide a really effective training experience, particularly in actual pipeline operations.
In 1996, the Pipeline College developed plans to embrace advanced training tools in order to increase the effectiveness of the training courses it offered. The focus was in two areas: pipeline operations; and Programmable Logic Controller (PLC) set-up and maintenance. To achieve an effective training environment for pipeline operations, a simulation training system was set-up using commercially available pipeline simulation software from Stoner Associates; the PLC training is based on Allen-Bradley equipment.
The operations training center computer systems were configured to accommodate ten trainees simultaneously running their own independent training sessions. The first training courses delivered by the Pipeline College using their new tools were presented in the summer of 1997.
This paper briefly chronicles the development of the pipeline industry in China as a background to the operation of the Pipeline College. The training center hardware and software configurations are described in some detail. The paper describes the Pipeline College’s first experiences of using these advanced training tools, and their plans for the future development of the training center.
Strain-Based Failure Criteria for Sharp Part-Wall Defects in Pipelines
Authors: Dinovitzer Aaron S. , Graville Brian A. , Glover Alan G. 
Published: October 2016

Failure criteria in current engineering critical assessment procedures for defects in pipelines and welds are stress-based. For example, failure is presumed to occur when the net section average stress reaches some arbitrary flow stress. These approaches are unrealistic for defects of limited length where loading of the net section (ligament) is essentially strain controlled. In order to improve upon this, the authors developed a strain-based failure criterion for part wall pipe defects in terms of the maximum ligament plastic extension. While this criterion[l] provided a basis for assessing the criticality of blunt defects, with respect to plastic collapse, it did not address sharp or planar defects which promote fracture.
As a defect becomes sharper, failure is determined more by local strain at the defect tip which is typically characterized by the crack tip opening displacement (CTOD). This paper describes the development of a sharp/planar defect strain-based failure criterion which relates the maximum ligament extension to the critical CTOD of the material. Two and three dimensional non-linear finite element analyses are used to determine local root extensions of circumferential defects which can be related to the loading, defect and pipe dimensions. The root extensions are calibrated to standard CTOD measurements through non-linear finite element analysis.
The failure criterion development process considers various defect lengths, material work hardening rates and material models. The failure criterion is compared with analytical and experimental data to demonstrate its predictive capability. The end result of this work is the development of an alternative acceptance criterion for sharp weld defects permitting more effective repair decisions to be made based on a more uniform level of reliability.
TransAlaska Pipeline System Linewide Slackline Investigations for Potential Pipe Vibrations
Authors: Tonkins W. G. , Baskurt U. J. , Hart James D. 
Published: October 2016

During the summer of 1996, the TransAlaska Pipeline System (TAPS) experienced pipe vibrations near Thompson Pass, which is located 25 miles north of the Valdez Marine Terminal (VMT). The VMT is the southern terminus of the 48-inch oil pipeline transporting Alaska North Slope Crude for further shipment to market via marine tankers. The pipeline is designed to operate in a slackline mode as it flows over the 2,810 ft. elevation of Thompson Pass.
As a result of the slackline experience gained at Thompson Pass, Alyeska evaluated other areas along TAPS where continuous slackline operation either existed in the past or could exist in the future with declining pipeline throughputs. A study determined that other locations along the pipeline could operate in a continuous slackline mode and should be investigated for potential slackline operating problems. This paper describes the slackline testing and evaluation and methods developed by Alyeska to control problems caused by slackline operation. General evaluations and observations of the slackline dynamics phenomena that can cause pipe vibrations along with guidelines and recommendations for the control or elimination of slackline vibration problems are presented.
An Automated ACFM Peak Detection Algorithm With Potential for Locating SCC Clusters on Transmission Pipelines
Authors: Carroll L. Blair , Monahan Craig C. , Gosine Raymond G. 
Published: October 2016

The Alternating Current Reid Measurement (ACFM) crack detection and sizing technique has demonstrated its potential as a stress corrosion cracking (SCC) characterization tool in studies conducted at Memorial University of Newfoundland (MUN). It’s ability to detect and size cracks through non-conductive coating thicknesses of 5 mm or more can have a significant impact on the costs associated with the current SCC investigation practices of many gas and liquid fuel transmission companies.
This paper outlines work conducted at MUN in automating the detection of SCC within ACFM signals. The technique may be refined and incorporated into SCC characterization procedures.
Strain Estimation Using Vetco Deformation Tool Data
Authors: Rosenfeld Michael J. , Porter Patrick C. , Cox James A. 
Published: October 2016

Damage to pipelines in the form of indentations and third-party damage has emerged as a key concern for operating reliability and public safety within the pipeline industry. Many operators have conducted detailed surveys of their pipelines for indentations (or simply “dents”) by means of in-line inspection tools designed to detect, measure, and report the presence, size, and location of dents, as well as other deformations such as buckles or wrinkles and ovality.
Described herein is a technique suitable for processing the signal from Tuboscope-Vetco deformation ILI tools in order to derive the local cold strain associated with indentation of the pipe.
The Role of Coatings in the Development of Corrosion and Stress Corrosion Cracking on Gas Transmission Pipelines
Authors: Wilmott Martyn , Erno Brian , Jack Tom , Worthingham Robert 
Published: October 2016

In order to protect pipelines against corrosion and stress corrosion cracking NOVA Gas Transmission (NGT) has employed a dual system involving the application of an insulating coating and effective cathodic protection to all pipelines. Since the installation of pipelines in the 1950’s the coatings of choice have changed with time. Construction in the 1950’s and 1960’s employed asphalt products which were hot applied over the ditch. Subsequently in the 1960’s and 1970’s polyethylene tape coatings were used extensively. Today the coatings of choice on the NGT system are fusion bond epoxies and extruded polyethylene systems.
This variety in the types of coating employed to protect pipelines against corrosion has necessitated a requirement to understand the long term performance of coating products. Studies at NOVA Research & Technology Corporation have been aimed at developing an understanding of the modes of failure of coating systems. The mode of failure of a specific coating system can impact significantly on the nature and severity of the resultant corrosion scenarios. Different coating systems under identical field conditions can fail in completely different ways. Examples from field coating failures will be described which show the significance of the mode of failure with respect to corrosion and stress corrosion cracking.
Laboratory studies using polyethylene tape, asphalt enamels and fusion bond epoxy coatings will be described which clearly demonstrate that coating failure modes are a key with respect to the type of corrosion scenario that is ultimately developed at the steel surface.
Such information is important in the development of site specific risk assessment models for the management of pipeline integrity.
Effects of Hydrostatic Testing on the Growth of Stress-Corrosion Cracks
Authors: Zheng W. , Tyson W. R. , Revie R. W. , Shen G. , Braid J. E. M. 
Published: October 2016

Two hydrostatic tests were carried out on an X-52 (Grade 359) pipe containing sixteen cracks of depths up to 55% wall thickness. Stress corrosion cracking (SCC) growth rates were measured in full-scale tests performed before and after the first hydrotest in order to demonstrate the effects of hydrostatic testing on subsequent crack growth rates. The effects on crack tip deformation were investigated by metallographic examination of crack cross-sections immediately following the second hydrotest.
The SCC tests were performed using a saw-tooth type load spectrum with the maximum stress set at 95% of the actual (as opposed to specified minimum) yield strength of the linepipe and R = 0.8. During the first hydrotest, the maximum applied stress was 108% of the yield stress; the total hoop strain in the pipe body reached about 0.2%, which is less than would have been reached in a uniaxial tensile test at this stress level because of the effect of the biaxial stress state in the pipe. The highest SCC growth rate measured before the first hydrotest was about 0.88 mm per year (2.4 * 10−3 mm/day), and the growth rate of the same crack after this hydrotest was about 0.37 mm per year (0.79 * 10−3 mm/day). The other cracks all showed varying degrees of reduction in growth rate.
Post-mortem examination indicated that the hydrotests did not cause significant crack blunting. The beneficial effects of hydrotests are attributed primarily to the presence of compressive residual stresses in the heavily deformed region in front of the crack tip.
The majority of cracks showed some growth during the first hydrotest. SCC growth and growth during the hydrotests are associated with distinctly different microscopic features on the fracture surface.
Initiation of Environment Induced Cracking in Pipeline Steel: Microstructural Correlations
Authors: Wang Y.-Z. , Revie R. W. , Shehata M. T. , Parkins R. N. , Krist K. 
Published: October 2016

Initiation of environment-induced cracks in pipeline steels involves interactions among microstructural features, loading conditions and environmental variables. Cyclic, or dynamic, loading has an important role in crack initiation, a competitive process in which cracks form first at the most favorable sites.
Under simultaneous cyclic loading and exposure of a Grade 448 (X-65) pipeline steel to aqueous solution of near-neutral pH, NS-4 solution saturated either with CO2 or 5% CO2/ balance N2, cracks that initiated early in the process were associated with pits. A correlation between pits and non-metallic inclusions has been observed. Other locations favorable for localized corrosion attack, such as along the steel surface at the edge of a coating, were also found to be sites for crack initiation. The dense population of cracks that appeared at a later stage of exposure most likely developed from slip-dissolution along certain crystallographic planes. Cracks that formed at an early stage did not always remain as the largest cracks, as crack coalescence, dormancy and/or re-activation, as well as initiation of new cracks, all occurred simultaneously on different parts of the exposure surface.
Full-Scale Wrinkling Tests and Analyses of Large Diameter Corroded Pipes
Authors: Smith Marina Q. , Nicolella Daniel P. , Waldhart Christopher J. 
Published: October 2016

The aging of pipeline infrastructures has increased concern for the integrity of pipelines exhibiting non-perforating wall loss and settlement induced bending. While pressure based guidelines exist which allow pipeline operators to define operational margins of safety against rupture (e.g.; ANSI/ASME B31-G and RSTRENG (Battelle, 1989)), reliable procedures for the prediction of wrinkling in degraded pipes subjected to combined loading are virtually non-existent. This paper describes full-scale testing and finite element investigations performed in support of the development of accurate wrinkling prediction procedures for the Alyeska Pipeline Service Company. The procedures are applicable to corroded pipes subjected to combined loading such as longitudinal bending, internal pressure, and axial compression.
During the test program, full-scale 48-inch diameter sections of the trans-Alaska pipeline were subjected to internal pressure and loads designed to simulate longitudinal bending from settlement, axial compression from the transport of hot oil, and the axial restraint present in buried pipe. Load magnitudes were designed based on normal and maximum operating conditions. Corrosion in the pipe section is simulated by mechanically reducing the wall thickness of the pipe. The size and depth of the thinned region is defined prior to each test, and attempts to bound the dimensions of depth, axial length, and hoop length for the general corrosion observed in-service.
The analytical program utilizes finite element analyses that include the nonlinear anisotropic material behavior of the pipe steel through use of a multilinear kinematic hardening plasticity model. As in the tests, corrosion is simulated in the analyses by a section of reduced wall thickness, and loads and boundary constraints applied to the numerical model exactly emulate those applied in the full-scale tests.
Verification of the model accuracy is established through a critical comparison of the simulated pipe structural behavior and the full-scale tests. Results of the comparisons show good correlation with measurements of the pipe curvature, deflections, and moment capacity at wrinkling. The validated analysis procedure is subsequently used to conduct parameter studies, the results of which complete a database of wrinkling conditions for a variety of corrosion sizes and loading conditions.
Application of Material Standards and ISO Quality Management Systems
Authors: Coulson Keith E. W. , Quinton Dennis G. , Slimmon Thomas C. 
Published: October 2016

Since the early 1970’s, the pipeline construction and operation industry has supported the development and implementation of various material standards and specifications. The emphases within the pipeline energy industry was to standardize manufacturing and performance testing processes in the provision of a product which would ensure public safety and reliability of service. The pipeline segment of the energy industry has succeeded in incorporating minimum quality levels by way of industry standards, codes, regulatory requirements and propriety company standards. In addition to these minimum product requirements quality assurance programs have been introduced to enhance the likelihood of conformance to the applicable requirements. In 1975, Canada became the first country to prepare and publish quality system standards for commercial use (Z299 standards). International quality system standards development proliferated in the following years, leading to the establishment of the ISO/TC 176 work team which subsequently led to the issue of the internationally accepted ISO 9000 series of standards.
This paper will review both the concept and stages of development of CSA pipe and coating standards. It will also analyze the impact that international standards for Quality Management Systems are having in establishing systematic approaches to assessing levels of quality during material manufacture. Finally, a vision of the possible road to the future will be drawn and the positive impacts for the pipeline industry will be projected from a full life cycle cost perspective.
Reliability of Mechanised UT Systems to Inspect Girth Welds During Pipeline Construction
Authors: de Raad Jan A. 
Published: October 2016

As an alternative to radiography, a field-proven mechanized ultrasonic inspection system is discussed. Called Rotoscan, this system has been developed for inspection of girth welds during construction of long-distance pipelines, both on- and offshore. It is characterized by high inspection speed and instant recording of results. Unlike prevailing radiography, it provides immediate feedback to the welders.
Recent technical improvements in flaw sizing and recording have allowed the application of rejection/acceptance criteria for weld defects based on fracture mechanics principles. The development and actual use of such modern acceptance criteria, particularly in Canada, supported the introduction of mechanised ultrasonic inspection. World wide applications proved that, contrary to expectations, ultrasonic inspection does not lead to higher weld repair rates than radiography does. Between early 1989 and now, over 5.000 km of pipeline (300.000 welds) were inspected with Rotoscan and its reliability proven.
The introduction of colour enhanced transit distance “C-scan mapping”, producing a coherent picture based on the signal’s transit distance, enabled the system to cope with most existing ultrasonic procedures and acceptance criteria, because of its capability to detect and quantify volumetric defects. Moreover, the integrated simultaneous Time Of Flight Diffraction (TOFD) function enables through-thickness sizing of defect. The present system is capable of achieving a high Probability Of Detection (POD) together with a low False Call Rate (FCR).
In the meantime, Rotoscan has been qualified in various countries, for different customers and for a variety of weld processes, pipe diameters and wall thicknesses. Because of its features, the now mature system has demonstrated its capabilities also for use on lay barges as an alternative to high-speed radiography.
Quality and Productivity Improvements in the Field Welding of High Strength Thin Walled Pipelines
Authors: Barbaro Frank J. , Henderson Ian D. , Dunne Druce P. , Painter Michael J. , Norrish John , Harrison Robert P. 
Published: October 2016

During the past 20 years the Australian Pipeline Industry has achieved significant economic improvements in the design and construction of natural gas transmission pipeline networks. This improvement is based on the use of thin walled high strength high pressure pipelines which serve relatively small markets separated by long distances from gas reserves.
The Industry in conjunction with the WTIA/APIA Research Panel 7 and the Cooperative Research Centre for Materials Welding & Joining, have developed a research program with a number of key deliverables which aim to improve the overall economics of pipeline design, construction, inspection and maintenance activities by providing the level of assurance necessary to confidently build reliable pipelines using high strength linepipe including X80 grade.
This paper details recent developments in the Australian Pipeline Industry and the coordinated research and development program to advance the economic use of high strength pipeline technology under Australian conditions.