bluuebunny/crossref_metadata_2025_split huggingface dataset:
Safety Considerations for the Transport of Hydrogen Gas in Line Pipes and Induction Bent Pipes
Authors: Genchev Georgi , Mentz Juliane , Brauer Holger , Kalwa Christoph , Muthmann Elke , Ratke Daniel 
Published: December 2022

Abstract
With increasing impact of hydrogen-based economy it is necessary to consider relevant hydrogen embrittlement effects and risks resulting from it. As higher gas pressures are in discussion, the use of higher steel strength levels as compared to existing pipelines appears reasonable. Clarifying the product requirements is necessary for safe operation. Lately, the interaction of pressurized hydrogen gas with steel has been studied more detailed. This allows more precise safety considerations for the transport of hydrogen gas. The results of laboratory trials of different semi-finished products (medium and large diameter line pipes, induction bent pipes) exposed to hydrogen gas will be used to clarify this point. Several laboratory test methods were selected, allowing to focus on local effects of hydrogen enrichment in conjunction with mechanical loads. Challenges when testing in high pressure hydrogen environment result mainly from the safety aspects to be respected, but also from precautions required to achieve reproducible test conditions and to avoid unwanted system contaminations.
Substantiated test results indicate excellent behavior of the materials tested in terms of ductility and fracture toughness in high pressure hydrogen applications; all relevant ASME criteria for material selection are fully met.
To support the ongoing discussion regarding hydrogen testing protocols and relevant material properties (toughness parameters) in both, qualification of components and design of pipelines, Salzgitter and its Steel Processing business units are planning further extended R&D studies.
An Improved Axial Surface Crack Model to Predict Crack Growth and Burst Pressures Based on FE Analyses For Jplastic And J-R Curve Methodology
Authors: Wilkowski Gery , Hong Jeong K. , Brust Frederick W. , Hioe Yunior 
Published: December 2022

Abstract
During an in-depth review of the MAT-8 method, it was noted that there were assumptions for determining the FAD-curve shape by matching three points along FAD curves from FE analyses to get the plastic contribution of the crack-driving force (Jpl). Because the FAD-curve shapes from the FE analyses for different flaw sizes (depths and lengths) of interest for liquid line operation were quite different from both the MAT-8 assumed FAD-curve shapes and the FAD-curve fitting function for the FE-based FAD curves, an alternative procedure was pursued. For the cases of deeper and longer flaws, FAD-curve shapes cannot be found easily due to the highly nonlinear plastic behavior. To develop a new FE-based crack-driving force equation, a modification of the GE/EPRI basic formulation with contributions for elastic and plastic crack-driving force relationships was implemented. Several hundred FE analyses for axial surface cracks in pipes were performed. The new procedure was developed first by separating the elastic contribution from the total Japplied, then using the plastic part of Japplied versus pressure (Jpl-P) curve to establish an analytical solution. A nonlinear-regression analysis of the FE results from the entire Jpl-P curve was used, not just a few selected points. The new Jpl-P analytical solution showed good agreement with the carefully conducted FE-based solution from short, shallow flaws to deep, long flaws. The MAT-8 based solutions were good for short flaws, but deviated from the FE-based solution with both larger flaw depths and lengths. In addition to the new procedure, we included the use of the J-R curve for surface cracks which has been found to be a function of the surface crack a/t in pipe and SEN(T) tests, i.e., toughness is not a constant for all surface crack geometries which is discussed in other papers. Predicted burst pressures from the various methods including the new procedure were compared to pipe tests are presented.
Assured Utilization of Vintage Pipelines Through Effective Pressure Fluctuation Management
Authors: Al-Otaibi Senhat , Al-Muslim Husain 
Published: December 2022

Abstract
New policies driven by climate change concerns have made the construction of new pipelines more difficult with uncertain prospects in the years ahead. With expected increasing demand in hydrocarbon transportation, pipelines operators have no alternative but to plan for further use of existing vintage pipelines. These pipelines have inborn flaws such as longitudinal seam weld defects or environmentally assisted defects such as stress corrosion cracking (SCC). Therefore, the need to proactively maintain pipeline integrity and mitigate failure probability has become essential to meeting customers’ demands and protecting the public. This paper discusses Saudi Aramco’s experience in monitoring pressure fluctuation for vintage pipelines that are susceptible to SCC.
Pressure fluctuation contributes to an increase in crack-like longitudinal defects that are common in vintage pipelines. Therefore, a pipeline integrity management program should consider pressure fluctuation-induced fatigue damage. In addition, a crack growth prediction model can help determine an appropriate re-inspection interval. This paper discusses an innovative approach to evaluating, categorizing, real time monitoring, and reducing pressure cycle aggressiveness by reviewing the pressure cycle history in a complex pipeline network and analyzing several factors contributing to pressure fluctuation.
There are several pipeline operation modes; the transmission pipeline pressure cycling index is mostly critical at the pump or compressor stations and is dependent mainly on the equipment operations. As upstream gathering pipeline systems most often have multiple tie-ins at several wellheads, each wellhead becomes a source of pressure in the pipeline network. Moreover, pressure fluctuation is a result of different operation activities; for instance, pigging operations contribute in some cases to up to 20% pressure fluctuation during each pigging activity.
In this paper, an innovative real-time monitoring method is utilized to proactively determine which pipelines are subjected to pressure fluctuation. Meanwhile, cyclic index monitoring was conducted with a digital tool to facilitate large data processing utilizing introduced methodologies that are dependent on fatigue damage rate instead of material strength. More than half a million data points were processed to identify the cyclic index for each pipeline segment for one year. A cyclic index categorization was introduced; therefore, when the pressure cycling index is moderate or higher, pipeline operators should investigate the operational factors to reduce the fluctuation effects. In addition, a fatigue assessment with the recently developed PRCI MAT-8 fracture mechanics model was conducted to predict remaining lifetime and determine appropriate inspection intervals. The technique for assuming the initial flaw size was based on API 1176, which is critical for pipelines with no hydrotesting history.
Use of Inertial Measurement Unit In-Line Inspection Data to Support Code Stress Compliance and Integrity Evaluations
Authors: Prescott Jonathan , Patterson Curtis , Najeeb Arfeen 
Published: December 2022

Abstract
Pipelines are an essential segment of infrastructure required to transport a variety of products to markets in our economies. The integrity and safe operation of those pipeline necessitates that pipeline operators have a thorough understanding of their pipeline systems, their configuration, and the changing operating condition within their pipeline networks. Inertial measurement unit (IMU), a technology that can measure the angular rate and acceleration and when combined with global positioning and navigation equipment such as pipeline above ground markers, can calculate position and orientation with 6 degrees of freedom: x, y, z, and pitch, roll, and yaw. IMU launched within the pipeline via in-line inspection tool trains, can be used to develop accurate three-dimensional geometry of the pipelines they inspect. This information can be used to confirm the geometry of the pipeline (i.e. degree of roping, bend angle, bend radius, and other abnormalities observed within the generated centerline from the inspection based on conventional construction practices). Therefore, the application of IMU technology within pipeline design and integrity work can be a useful tool in providing the necessary input information which can support ongoing studies such as verification of maximum operating thermal differentials which can be imposed on a pipeline to remain compliant with governing pipeline codes, and/or the information can be used to perform gap analysis studies with other integrity records (alignment sheets, as-built pipe tallies), or to support other pipeline integrity evaluations. When IMU data is processed with mathematical techniques essential information from IMU data can be obtained such as bend angle, bend radius, and degree of installed curvature. A case study showing the results of the application of processed IMU data for as-built evaluation is presented and its use to help support a variety of decision making is discussed. The IMU data is a key data input when constructing detailed finite element models for on-going stress analysis studies.
Probabilistic Flaw Growth Rate Estimates Using Multiple Inline Inspection Tool Run Data Analyses
Authors: Scott Colin , Philpott Kregg 
Published: December 2022

Abstract
Many pipeline operators perform run comparisons (or “run-corns”) during assessment of their inline inspection data. Analysts match corrosion pit depths reported in back-to-back tool runs and estimate corrosion growth rates, remaining lives, and appropriate reinspection intervals. This approach is generally deemed more accurate than using an assumed constant growth rate for all reported features. However, the accuracy of each estimate is subject to the depth sizing error inherent in the measurements. The larger a dataset, the higher the likelihood of many calculated corrosion growth rates being misleading. This is due to there being a higher likelihood of extreme depth sizing errors. A first run undercall followed by a second run overcall compounds the depth sizing error and may result in an overly conservative decision. A first run overcall followed by a second run undercall and may result in a missed defect. Both scenarios can lead to a misuse of resources.
This work is a statistical analysis of flaw growth that considers and accommodates for depth sizing errors. The result is that the growth rate for each ILI reported flaw is considered probabilistically. Advanced data ingestion algorithms allow analysts to align multiple ILI tool run data sets quickly and conveniently, opening the door to advanced data analytics, including work with non-linear flaw growth rates. This work looks at corrosion and SCC growth rates (approximated as linear) and fatigue crack growth rates that follow established Paris Law behavior (non-linear).
Squeeze the Crack Out of It - With Type A Compression Sleeves
Authors: Futch David B. , Ganpatye Atul , Wilson Josh 
Published: December 2022

Abstract
Type A Compression Sleeves have been a technically viable repair method for corrosion, lamination-like features, and longitudinal crack-like features for the past 20+ years. A Type A Compression Sleeve relies on thermal expansion/contraction of the steel sleeve, which once the sleeve long seam welds are made, results in a compressive hoop stress in the carrier pipe at levels equal to or greater than generated at max operating pressure. This repair technology has been mostly marketed in Canada, and therefore, CSA Z662 includes the Type A Compression Sleeve in their list of approved permanent repair technologies. Over the past five years, there’s been an increased awareness in the United States as the technology has become referenced in industry documents such as the PRCI Pipeline Repair Manual and API 1176.
This paper provides an overview of a Type A Compression Sleeve, including the basis of how the repair system functions and how the sleeve is installed. Finally, this paper presents a series of full-scale tests and numerical modeling validating this innovative repair system. The use of induction heat, rather than open flame, provides a more consistent and traceable heat signature, allowing for confidence in the installed repair. Tests include synthetic cracks generated by precracking an EDM notch to generate a sharp-tipped crack, then heat tinted to provide a distinguishable boundary. The EDM notches, installed at a maximum of 50% of the wall thickness within the ERW seam, were subsequently repaired via the induction heating sleeve technology with and without flowing water in the carrier pipe. Test samples were cycled to 100,000 cycles, burst, and metallurgically examined. Post-test examination of the fracture surfaces revealed no discernable growth, therefore, indicating the technical viability of the repair technology as a permanent repair of crack-like features and provides an Operator another option when making repair decisions.
Stress-Relief Excavation for Pipeline Geohazard Mitigation
Authors: Ahmadipur Amir , Ebrahimi Ali , Mosaiebian Arash , Cook Doug 
Published: December 2022

Abstract
Pipelines are linear structures that cross various slope geometries and geologies and are susceptible to various ground movement geohazards, including landslides and subsidence. The ground movements from the geohazards can potentially induce axial, bending, and torsional stresses in pipelines.
The objective of this paper is to summarize the strain relief process, demonstrate that strains can be estimated without IMU using the shape of the pipe measured in the field, and describe the pipeline performance before, during and after stress-relief excavation.
This paper will also present planning considerations prior to conducting a stress-relief excavation, including design considerations, geotechnical stability, and considerations related to conditions of the pipe. This paper will present an approach to approximate pipe shape and estimate bending strains in the pipe and includes a discussion on results of three case-studies of stress-relief excavations. These case studies include landslide movements of various directions with respect to a pipeline. A summary of pipeline out-of-straightness, inertial measurement unit bending strain, rebound measurement during the stress-relief excavation, and strain measurement using strain gauges are included.
A Risk-Based Safety Class System for Onshore Pipelines
Authors: Nessim Maher , Stephens Mark , Yue Howard 
Published: December 2022

Abstract
A consequence-based safety class system was developed as an alternative to the class location system currently used as the basis for defining the maximum allowable hoop stress in Canadian Standard Association’s Standard Z662. The system accounts for the key pipeline, service fluid, and right-of-way parameters affecting the safety and environmental impact of releases from pipelines transporting natural gas, low- and high-vapour-pressure liquid hydrocarbons, sour gas, carbon dioxide, multiphase, and oilfield water pipelines. This paper describes the safety class system and the simplified release consequence modelling approach developed to support its implementation.
Companion papers provide more detail on the release hazard analyses used as a basis for consequence modelling, and the application of the safety class system as a basis for defining pressure design hoop stress factors that achieve acceptable and consistent public safety and environmental protection levels for all pipelines considered.
Predicting the Future by Mapping the Past: Revolutionary Innovations in Lidar Change Detection Analysis are Enabling Regional Scale Mapping and Identification of Threats From Geohazards
Authors: Lato Matthew , van Veen Megan , Ferrier Alex , Weidner Luke , Graham Alex 
Published: December 2022

Abstract
Managing pipeline integrity with respect to natural threats requires geoprofessionals to consider how the earth may behave into the future. Predicting morphological change involves a deep understanding of geology, geological processes, climate change, and knowledge of physical changes that have happened in the past or may occur in the future. One of the most capable techniques for mapping changing terrain through time across spatially extensive regions is lidar change detection (LCD) with airborne lidar scanning (ALS) data.
LCD has typically been performed on a site-specific basis at known geohazard locations. However, with recent developments in data acquisition and processing, LCD is now a cost-effective tool that can be used on a systemwide scale to aid in the identification of potential geologic hazards and monitor known geohazard sites for active ground displacements that may be impactful to pipeline infrastructure. It enables monitoring of hazards directly impacting the right of way, as well as peripheral hazards that could encroach on the right of way. This proactive method of identifying and monitoring geohazards significantly enhances the ability of pipeline operators to make informed decisions and design resilient infrastructure. The work presented demonstrates how over 40,000 linear kilometers of LCD analysis was executed and integrated with a geohazard management program to support proactive decision-making across the eastern US.
Post-Heating as an Alternative to Delayed Nondestructive Examination (NDE)
Authors: Gould Melissa , Bruce William A. , Scoles Russell 
Published: December 2022

Abstract
The current preference of regulators in the United States and Canada is to require a delay time prior to nondestructive examination (NDE) of welds for cracking; for both welds made manually during construction of new pipelines and during maintenance activities for existing pipelines. A better approach than imposing a delay time is to prevent cracking, by lowering the bulk hydrogen below a threshold value necessary for cracking to occur. The proactive approach of using post-heating immediately after welding to prevent the weld from cracking in lieu of an inspection delay was explored.
An experimental program was carried out to determine the hydrogen diffusion rate in pipe materials, as well as the typical weld hydrogen levels in both a baseline (room temperature) and time and temperature conditions. Experiments were also conducted to measure hydrogen levels in simulated welds in the as-welded condition, after 24 hours at ambient temperature, and after post-heating. The experimental program showed that post-heating newly constructed girth welds made using cellulosic-coated electrodes for approximately 20 minutes at 200 °C (400 °F) and in-service welds made using low-hydrogen electrodes for approximately 20 minutes at 120 °C (250 °F) may be used to mitigate the risk of hydrogen-assisted cold cracking (HACC), thereby justifying immediate inspection.
Various heating methods were evaluated to determine how effectively the post-heating time and temperature targets could be achieved for new construction welds and for in-service welds.
To aid in the successful implementation of post-heating, guidance material suitable for use by field personnel in the application of post-heating, as well as recommendations for industry standards improvement were developed.
Diagnosis and Recognition of Pipeline Damage Defects Based on Neural Network Algorithm
Authors: Zhang Min , Guo Yanbao , Wang Deguo , Du Qiang 
Published: December 2022

Abstract
Oil and gas are the main sources of energy for national economic development. Pipelines are the main means of transportation for oil / gas. It is an important national energy infrastructure, which is known as a “lifeline project”. As the mileage of pipelines increases, defects such as cracks, dents, corrosion as well as mechanical defects caused by changes in external forces occur frequently. Defects can result in pipeline ruptures, fires, property damage, and casualties. According to professor Giovanni’s assessment of pipeline accidents, pipeline defects are mainly caused by third party activities, corrosion and mechanical failure, accounting for 78.1% of all pipeline defects. Therefore, it is particularly important to conduct safety checks on pipelines. There are many pipeline defect detection techniques. One of these is the widely used pipeline magnetic flux leakage detection technique, having the advantage of being fast and efficient, which is suitable for detecting defects in pipeline ferromagnetic metallic materials. Most pipelines are located in harsh outdoor environments with various corrosion and mechanical damage defects. There are axial damage and circumferential damage to the pipeline, resulting in a wide variation in the leakage field. Coupled with this, there is a variety of interference in the signal, so the current pipeline defect identification diagnosis and prediction accuracy are low, with the identification accuracy maintained at around 90%. Therefore, to improve the recognition accuracy, a neural network algorithm was designed to identify and analyze the detection signals. By using a multilayer neural network for training and learning, the recognition accuracy and reliability of pipeline defects are improved. Further, a safety detection basis is provided for the development of the pipeline business. The main contributions are as follows: First, a pipeline defect magnetic flux leakage detection simulation platform is described. Then, pipeline defect detection as good as signal collection are completed. Second, the data is fused and processed, togethering with setting to produce a neural network dataset. Third, a neural network structure is produced to analyze and study the collected pipeline signals. This paper completes the identification of magnetic flux leakage information of pipeline defects, and lays a foundation for future pipeline safety assessment to establish a safe pipeline operation system.
Gaps in the Current Strain-Based Dent Assessment
Authors: Wang Rick , Zhang Ken 
Published: December 2022

Abstract
Dents in pipelines, especially when associated with crack formation, pose a significant pipeline integrity threat. With crack formation during the initial indentation process, the fatigue life and failure pressure can dramatically reduce compared with crack-free dents. Over the past decade, cracks associated with the dent-formation process were typically assessed using strain-based engineering critical assessment (ECA), which compares the dent strain and curvature measured by in-line inspection (ILI) geometry tool, with industry-established damage criteria.
However, in recent dent management practice, TC Energy has observed cracks in several shallow dents with strain levels much lower than any established fracture criteria. Cracks were found at some dents with measured depth at only 1.3% outer diameter (OD), and the calculated strain with ASME B31.8 nonmandatory method was ∼4% [6]. It is believed that the strain-based assessment solely based on post-formation shape measured by ILI geometry tool likely requires improvement to capture additional aspects that might contribute to formation of dent-cracks.
Various dent formation processes were reviewed, and the multiple potential contributing factors are discussed in this paper, including loading rate sensitivity, temperature effect, stress triaxiality and geometrical influence. The effects of these factors on material responses, dent-crack formation and fracture damage are outlined. Observed gaps in the current strain-based dent assessment process are also outlined, and a multi-element approach to assess dents and identify dent-induced cracks is proposed, which includes evaluation of combined Caliper, magnetic flux leakage (MFL), electromagnetic acoustic transducer (EMAT) and axial flaw detector (AFD) data, enhanced dynamic testing and ductile failure damage indicator (DFDI) determination, materials modeling and finite element analysis (FEA) techniques. Results of two case studies using multiple real-life dent features are described to illustrate effectiveness of the proposed approach.