bluuebunny/crossref_metadata_2025_split huggingface dataset:
Verification of Applicability of Battelle Two-Curve Method to Ultrahigh-Pressure Rich-Gas Pipelines Based on a Full-Scale Burst Test
Authors: Imai Yasuhito , Mitsuya Masaki , Toyoda Masao 
Published: November 2018

A full-scale gas burst test was conducted to confirm the behavior of unstable ductile crack propagation and arrest and to confirm the required toughness value to prevent unstable ductile fracture under an ultrahigh pressure of 18 MPa. A full-scale test was conducted at the Spadeadam test site in the UK for unburied pipes. The test pipes used in this test were of API 5L Grade L450 with outer diameter of 610 mm and thickness of 17.5 mm. The toughness of the test pipes increased away from the center, where an explosive charge was placed across the top of the girth weld for crack initiation. The gas used in the test consisted of ∼89% methane and other heavy hydrocarbon gas components, and the test temperature was 0 °C. A gas circulation loop was constructed to ensure that a homogeneous gas mixture and temperature were achieved throughout the test rig.
In addition to dynamically measuring the ductile crack velocity and decompression behavior of the rich gas, as has often been done in previous burst tests, the circumferential distribution of the decompression behavior was measured using circumferentially placed pressure transducers. Furthermore, the fracture strain near the propagating crack was measured.
The initiated unstable ductile crack was arrested in the third pipe. From the material properties of the test pipes in which the unstable ductile crack was arrested, the required Charpy absorbed energy and DWTT absorbed energy to prevent unstable ductile fracture in unburied pipes were obtained. In addition, the above data can be useful for validating numerical models that evaluate the propagation/arrest of unstable ductile fracture.
The required Charpy and DWTT absorbed energy values obtained in this test were compared with those predicted by the Battelle Two-Curve Method (BTCM). As noted in previous studies, it was confirmed that the BTCM underestimates the required Charpy absorbed energy and requires a certain correction factor for precise evaluation, whereas the DWTT absorbed energy predicted by BTCM was consistent with the experimental result.
Do You Have Wrinkles? A Strain- and Stress-Based Approach for the Assessment of Wrinkles Reported by In-Line Inspection
Authors: Holliday Chris , Wynne Dominic , Clyne Alasdair , Wilde Andrew 
Published: November 2018

Improvements in in-line inspection (ILI) technology have led to an increase in the probability of detection and ability to characterize geometric features such as wrinkles, the assessment of which was introduced into CSA Z662, “Oil & Gas Pipeline Systems”, in the 2015 version.
The CSA wrinkle acceptance limits are based predominantly on fatigue assessment criteria; part of the assessment procedure is confirmation that wrinkles are free from associated cracking. In practice, this often restricts the assessment to wrinkles that have already been investigated in-field and where the absence of cracking has been confirmed by non-destructive examination (NDE).
This paper describes the assessment of a series of wrinkles that exceeded the CSA height criteria, reported by ILI within field bends in an insulated liquid pipeline. Strain-based assessment, supported by in-field investigations, was used to investigate the likelihood of associated cracking.
Utilizing the high resolution caliper ILI tool data, three-dimensional profiles of the wrinkles were generated. Previous work that compared “tool-measured” with “field-measured” profiles identified that caliper tool measurements can underestimate the true depth and profile of wrinkles, this effect is more pronounced for particularly sharp wrinkles. The wrinkle profiles were therefore adjusted based on the historical field-tool correlation. Strain profiles were then calculated using the guidance within ASME B31.8 Appendix R. It was identified that the majority of the wrinkles exceeded the 6% strain limit commonly applied to dents.
One field bend containing multiple wrinkles was subsequently excavated in order to gather detailed profile information and to inspect for cracking. Upon excavation, the wrinkles were not visually apparent, but their presence was confirmed following removal of the insulating coating. Profile information was subsequently recorded using laser scanning technology. In addition, NDE confirmed the absence of cracking, despite the fact that the majority of wrinkles were associated with strain levels that exceeded the CSA limiting value, 6%. The laser scan data were then compared with the adjusted “tool-measured” profiles. It was observed that the adjusted measurements based on the ILI tool data were conservative, and in some cases excessively so. The caliper measurements were optimized by identifying a factor that could be systematically applied to the “tool-measured” wrinkle profiles, which provided consistency with the profiles measured by the laser scan, thereby improving the accuracy of the dimensions and strain estimation of the remaining (non-excavated) wrinkles.
Finally, a S-N based fatigue assessment was performed using operational cyclic pressure data and estimates of the stress concentration factors associated with the wrinkles. The calculated fatigue lives exceeded the expected operational life of the pipeline.
Real-Time Continuous Pipeline Integrity Monitoring Utilising Telecommunications Optical Fibre Cables
Authors: Hayward Peter J. , Fryer Tom A. 
Published: November 2018

A recent trend in the field of pipeline monitoring has been the utilisation of an optical fibre based distributed acoustic sensing (DAS) technology, for the purpose of security monitoring of buried pipelines [1–3]. The technology comprises an interrogator, connected to an optical fibre cable, which is interrogated to acquire coherent Rayleigh backscatter. Localised environmental vibrations may result in a proportional strain of the fibre. This strain results in a localised optical path length variation, resulting in a phase distortion in the measured signals. Application of signal processing techniques infer the characteristic of the originating stimulus, and thus identify and locate the source activity of interest. Activity may arise as a result of ground excavation, vehicular movement, or similar in the vicinity of the pipeline.
Researchers are now studying the possibility of utilisng this technology for the purpose of pipeline leak detection monitoring [4]. This paper provides a review of one such programme of work.
Results are presented for a permanent installation, where signatures relating to leaks were identified, and located in the resulting DAS data. Results are provided relating to liquid leaks, where product was emitted at a flow rate of 20.0l/minute and operational pressure 20.0bar.
Crack Shape Development for Leak-Before-Break Analysis in Pipelines
Authors: Zhang Kathy , Xu Luyao , Ferguson James , Zadery Dennis 
Published: November 2018

Surface cracks in pipelines under certain service conditions may grow due to fatigue, which is caused by pressure (cycles). The leak-before-break (LBB) assessment method is employed to avoid any catastrophic failure prior to a detectable leakage. In the LBB analysis, crack critical length is an essential element for determining the pipeline leak or rupture.
The common approach regarding the evaluation of LBB is to calculate the critical crack length and through-wall length under iven pressure cycling conditions. If the critical crack length is less than the through-wall length, LBB conditions could occur and be detected if leak detection capability is high. This involves complex calculations in crack fatigue growth and could result in extensive analysis if thepipeline has a large crack population.
This paper presents a simplified approach for assessing the leak-before-break of the flawed pipelines. This approach is based on industrial code API 579-1/ASME FFS-1 Fitness-For-Service. Through the investigation of effects for different parameters on crack growth, including crack initial geometry, pipeline materials, loading conditions, pipeline diameter and wall thickness, it was determined that the crack initial aspect ratio is a major factor influencing crack growth and geometry evolution. Based on these parameters, a crack fatigue growth map was developed. By comparing the behaviors of different cases, it was confirmed that the proposed method is a valid approach for the pipeline LBB analysis.
Are Integrity Management Programs Making a Difference?
Authors: Paviglianiti Joe , Murray Alan , Elabor Tijani (TJ) 
Published: November 2018

As a result of numerous stress corrosion cracking incidents in the 1980s and early 1990 the National Energy Board (NEB) held an Inquiry1 in 1995 on the SCC failure mechanism and how to prevent failures. One of the recommendations of the Inquiry was Companies were to develop a SCC management program to proactively identify and mitigate SCC. Based on the apparent success of the SCC programs in significantly reducing SCC failures, the NEB revised its Onshore Pipeline Regulations in 1999 (OPR-99)2 to require companies to develop an integrity management program (IMP) for all hazards.
This paper discusses the evolution of integrity management program (IMP) requirements and evaluates incident rates and other performance metrics to determine if there is evidence that IMPs have contributed to the improvement of safety of pipelines. The paper highlights the challenges associated with gathering incident and IMP performance metrics and evaluating the data to determine if there is a correlation between the implementation of IMP and pipeline safety. In addition, the analysis discusses the challenges associated with comparing data between different countries and regulatory jurisdictions. Suggestions for future improvement are identified.
Preserving Pipeline Integrity With Large Diameter Stone Columns at Dead Horse Creek Crossing, Southern Manitoba, Canada
Authors: Wong Wing-Keat (Wayne) , Wiebe Brad , Treen Curtis , Richmond John 
Published: November 2018

Pipeline integrity has been threatened at the Dead Horse Creek pipeline crossing in southern Manitoba by a slow-moving slope failure with a potential for crest retrogression. The movement zone extends from the slope crest to the bottom of the creek, a vertical distance of about 25 m and is approximately 80 m long from toe to scarp and 100 m wide along the creek. The slope has degraded over time and is controlled by the combination of local geology, which consists of weak colluvium overlying high plastic clay shale, and creek bank erosion and channel degradation. Saturated soil conditions, a function of poor drainage and elevated seasonal precipitation, have exacerbated the problem over the years.
The slope movements have been monitored on a regular basis since 2008 and presented an increasing risk to the integrity of multiple pipelines located in two rights-of-way (ROWs) situated within and immediately adjacent to the failing soil mass. The site is surrounded by various infrastructure and recreational areas that are key to the community, and therefore is considered a high consequence area with respect to potential pipeline failures. To manage the risk and protect pipeline integrity, various stress relief and other mitigating measures have been implemented since 2013 [1], culminating in a major slope rehabilitation project undertaken in 2015, which comprised earthworks, drainage and watercourse improvements, and slope stabilization using stone columns.
While the use of stone columns to stabilize embankments is not a new technique, it is not commonly used in the pipeline industry and represents another option for geohazard stabilization in the right situations. This paper presents the slope stabilization techniques employed and discusses the challenges of working on an active moving slope confined by a watercourse and live pipeline assets. The positive benefits of the stabilization measures are illustrated through the use of 2D and 3D numerical modelling, and confirmed through an ongoing geohazard management program that includes site inspection and instrumentation monitoring which continues to show improvements in slope performance post construction.
The Future of In-Line Inspection: Free-Floating Smart Sensors
Authors: van Pol Anouk , van Pol John , McNealy Richard , Goudy Clay 
Published: November 2018

Advances in micro-electronics and machine learning open the door to a new method of in-line pipe inspection: small free-floating smart sensors moving in the flow, capturing critical data and enabling operators to optimize pipeline performance, detect anomalies, and flag changes in pipeline condition.
The free-floating nature of these smart sensors allows for full length pipeline inspection without interrupting the operation. This makes frequent inspection possible turning it into a cost-efficient data driven solution. The alternative requires significant capital to modify the pipeline system to accommodate traditional ILI. Furthermore, traditional ILI methods are a one off costly and labor extensive measurement executed once every 5 to 10 years, where these free-floating sensors allow for high frequency, low cost measurements.
Frequent inspection allows for early detection of changes in the pipeline condition such as deposit formation and metal loss as well as timely detection and localization of leaks or similar hazardous conditions. The free-floating nature, combined with the capability to detect pipeline elements such as flanges and welds, permits accurate localization without the need for external markers.
An alternative to the free-floating deployment, the sensor device can also be attached to an off-the-shelf cleaning pig. This solution is especially suited for gas lines and allows for screening of the pipeline condition while cleaning the pipeline with limited extra effort from the operator.
The paper will demonstrate the outcome of over ten validation projects that have been conducted during the course of 2017 using an implementation of this technology in a golf ball-sized (1.5 inch diameter), robust and chemically inert integrated sensor system called Piper™. The Piper™ is equipped with a comprehensive set of sensors, consisting of a 3-axial accelerometer, gyroscope and magnetometer, a combined pressure and temperature sensor, and an advanced system for acoustic leak detection.
Topics that will be addressed include the advantage of using a free-floating integrated device, the capability of reconstructing positioning, the ability to locate and quantify leaks, and the ability to locate pipeline elements such as welds and flanges, and changes in wall thickness. In the Piper™ pig combination, the detectability of bends including the angle and radius of curvature will also be demonstrated.
Satellite Data Analytics for Natural Disaster Assessment and Application to Pipeline Safety
Authors: Piazza Mark , Gregorian Karineh , Robert Gillian , Svacina Nicolas , Gamble Lesley 
Published: November 2018

Understanding where, when, and how conditions are changing along the extent of an energy pipeline system, which can be vast, is a challenging task. The challenge can be even greater when natural disasters1 create a condition where access to affected pipelines, qualified personnel, and equipment is limited.
To address these challenges, pipeline operators are working directly with experts in satellite technology to develop innovative applications incorporating the use of satellite technology and analytical processes to improve natural disaster monitoring and response. Through recent experiences following Hurricane Harvey in the Gulf Coast region of the United States in August-September 2017 and the wildfires and mudslides in Southern California that occurred in December 2017 to January 2018, space-borne Synthetic Aperture Radar (SAR) satellite data was shown to be a useful tool for wide-area monitoring. Satellite-based SAR imagery has the unique advantage of penetrating through cloud cover and smoke and is capable of providing an early view of the extent of damage in both conditions.
Satellite data and continuous improvements to their derived analytical products have resulted in significant benefits for pipeline operators preparing for and responding to the effects of potentially damaging natural processes, including river scour, erosion, avulsion, mudslides, and other threats to pipeline integrity and public safety. SAR change detection algorithms and processes can provide effective results in identifying areas affected by natural disasters that are not readily available by other means. These methods also provide timely information for allocating and directing resources to the most critical locations in support of post-disaster assessment and analysis. SAR satellite data and Amplitude Change Detection (ACD) algorithms provided the basis for confirming where flooding near pipeline infrastructure was most substantial following Hurricane Harvey. In the case of the Southern Californian forest fires and mudslides in Ventura and Santa Barbara counties, recent investigations into ACD and Coherence Change Detection (CCD) algorithms showed promising results, providing a detailed view of damaged areas in near-real time.
This paper describes the process of collecting, analyzing, and applying satellite data for assessing the impacts of natural disasters on pipeline infrastructure, and the methods applied, consisting primarily of multiple change detection algorithms, that are used to process the large volume of satellite archive images to extract relevant changes. This paper also describes how these tools and products were practically applied to support decisions by pipeline operators to protect and ensure the integrity and safety of pipelines in the affected areas.
Ultrasonic NDE Technology Comparison for Measurement of Long Seam Weld Anomalies in Low Frequency Electric Resistance Welded Pipe
Authors: Torres Luis , Fowler Matthew , Bergman Jason 
Published: November 2018

In the pipeline industry, a widely accepted methodology for integrity crack management involves running ultrasonic In-Line Inspection (ILI) technologies. After an ILI tool run is completed, the performance of the tool is typically validated by excavating the pipeline and conducting in-the-ditch investigations. Ultrasonic Non-Destructive Evaluation (NDE) techniques are used in the field to characterize and measure crack-like features. These in-the-ditch measurements are compared back to ILI results in order to validate tool performance and drive continuous technology improvements. Since validation of the ILI tool relies on NDE measurements, acquiring accurate and representative data in the field is a critical step in this integrity crack management approach. Achieving an accurate field inspection comes with its challenges, some of which relate to complex long seam weld conditions present in older vintage pipelines including: weld misalignment, weld trim issues, and dense populations of manufacturing anomalies. In order to better understand the challenges associated with complex long seam weld conditions, an evaluation and comparison of the performance of NDE technologies currently available was conducted.
In this study, a portion of a Canadian pipeline with complex long seam weld conditions was cut-out and removed from service. Multiple NDE crack inspection technologies and methods from three different vendors were used to assess the condition of the long seam weld. Conventional Ultrasonic Testing (UT), Phased Array Ultrasonic Testing (PAUT), Time of Flight Diffraction (TOFD), and variations of Full Matrix Capture Ultrasonic Testing (FMCUT) were used to assess the long seam weld and their results were compared. The performance of all NDE technologies is baselined by comparing them with destructive examination of sections of the long seam weld. The newer NDE assessment methodologies were shown to be consistently more accurate in characterizing long seam features.
Liquid Pipeline Location Specific Cyclic Pressure Determination
Authors: Semiga Vlado , Dinovitzer Aaron , Tiku Sanjay , Vignal Geoff 
Published: November 2018

In the majority of liquid pipelines, the pump station discharge pressure ranges are much greater than the pressure ranges experienced at the suction end of the downstream pump station. Consequently, the cyclic pressure induced fatigue damage accumulation rate is greater at the discharge end than at the suction end of a given pipeline segment. In completing an integrity assessment of a fatigue susceptible feature, assuming that the pump station discharge cyclic pressure profile applies to all features in the line segment is conservative. This conservative assumption can lead to un-necessary repairs, unintentional damage from over-prescribed maintenance, or inefficient decisions regarding maintenance action prioritization.
The following paper presents the results of a Canadian Energy Pipeline Association (CEPA) initiative to develop a simple approach to define the cyclic pressure history at any point in a liquid pipeline segment based on the bounding discharge and suction pump station Supervisory Control and Data Acquisition (SCADA) pressure time history data. The approach was developed based on collected operating pipeline SCADA pressure time history data for line segments with intermediate measurement points which could be used to validate the developed model. The pressure time histories for all the locations were analyzed using a Rainflow cycle counting technique to develop pressure range spectra (i.e. histograms of pressure range events) and the cyclic pressure severity of each of the time histories was characterized by the Spectrum Severity Indicator (SSI). The SSI represents the number of annual 90MPa hoop stress cycles required to accumulate the same fatigue damage as the actual pressure spectrums.
The technique presented in this paper illustrates how to infer the pressure range spectra or SSI at intermediate locations. The technique is shown to be a significant improvement (i.e. higher location specific accuracy) than either applying the discharge pressure spectrum or applying a linear interpolation between discharge and suction conditions in fatigue life assessments.
The liquid pipeline cyclic pressure characterization technique presented in this paper will permit integrity assessment or severity ranking of features along a pipeline to be based on an accurate local pressure profile rather than an upper bound. This understanding will help to improve the accuracy of defect loading, one of the three main pillars in integrity assessment (i.e., loading, geometry, materials) for defects susceptible to cyclic loading (e.g., cracking, mechanical damage).