bluuebunny/crossref_metadata_2025_split huggingface dataset:
Going Beyond ASME B31.12: A Technical Feasibility Case Study for the Conversion of a 16” X 20 km Onshore Gas Pipeline to Hydrogen Storage
Authors: Sandana Daniel , Hopkin Sarah , Martin Tom , Gallon Neil , Doyle Jonathon , Guijt Wim , Timmerman Robert , Baby Benjose 
Published: December 2024

Abstract
The conversion of existing assets to hydrogen needs to be managed with due diligence. Current industry codes such as ASME B31.12 have remained relatively immature in their approach to repurposing and do not yet reflect the rapidly evolving research developments in this areas, for example accounting for the presence of historic defects and damages. This paper proposes a method for pragmatic and safe pipeline repurposing that presents the project with an early screening of major barriers that may potentially compromise repurposing. In line with current industry knowledge, this approach includes the removal of conservatisms associated with some of the design equations given in existing codes i.e. ASME B31.12.
The case study provided to illustrate this process is a 20 km 16″ pipeline proposed for conversion to hydrogen storage. The overall objective was to define a safe operating envelope within which the capacity of all segments of the vintage pipeline can be maximized. The input data, assumptions made where data was unavailable or incomplete, engineering critical assessment methods and defect compliance criteria, and results are provided. The operating envelope is tested against potential H2 operating cases, and a test and inspection plan proposed to confirm the assumptions made as future work. Conservative decisions in light of open industry gaps are highlighted where applicable.
The study provides a clear, documented demonstration of feasibility for hydrogen storage within a specified operating envelope of restricted pressure and pressure cycling before further committing to subsequent repurposing strategy phases.
Development and Implementation of a Dent Engineering Critical Assessment (ECA) in Accordance with PHMSA’s Gas Mega Rule
Authors: Tang Huang , Kohlenberg Derek , Sun Jialin , Zheng Guanbo , Oviedo Fernando , Di Blasi Martin 
Published: December 2024

Abstract
In the 2019 US Gas Transmission Rule referred to as the “Mega Rule”, PHMSA introduced a new section within CFR 192.712 [1], allowing operators the opportunity to develop procedures and perform Engineering Critical Assessment (ECA) leveraging industry standards such as API RP 1183, ASME B31.8S [2, 3], or other current research findings to determine if dents and mechanical damage anomalies should be responded or monitored beyond the prescriptive requirements referenced in CFR 192.714 and CFR 192.933. In addition, PHMSA provided guidelines to operators on what an acceptable ECA procedure should consider. If an operator chooses to perform an ECA process, submission of advanced notification with the relevant procedures in accordance with CFR 192.18 would be required.
For operators to assess a prevalent pipe integrity threat such as dents, industry standards refer to multiple levels of assessment methods, with increasing orders of complexity and decreasing levels of conservatism. The purpose of this paper is to provide technical suggestions on the development and implementation of an ECA workflow to assess dents and to determine their fitness for service. This paper provides suggestions on how to address plain dents with strain levels potentially exceeding 10% strain limit which typically can account for a significant portion of the dents identified through ILI. The paper also describes the FAD-based method to conduct fracture assessment on cracks/gouges coincident with dents. A workflow was also developed to conduct fatigue crack growth assessment on dents interacting with cracks/gouges in accordance the CFR Mega Rule requirements.
Finally, a software tool has been developed to automate the dent ECA process. With this automation, the efficiency in conducting dent ECA could be significantly improved ensuring that a prompt action will be taken on potentially injurious dents. A case study on hypothetical dents was conducted demonstrating the robustness of the workflow performed with the automation tool.
Real-Time Detection of Solid and Liquid Contaminants in Natural Gas Streams Using Microwave Sensing Technology
Authors: Chan Nicholas , Botros Kamal K. , Saif Ur Rahman Mohammed , Abou-Khousa Mohamed , Alshehhi Mohamed , Al-Wahedi Khaled , Leong Keith 
Published: December 2024

Abstract
The production and transportation of high-quality natural gas, that is free of liquid/solid contaminants, is critical to fulfilling the increasing global demand of this commodity. Despite several mitigation strategies from natural gas producers and distributors, liquid and solid contaminants are still commonly found within natural gas pipelines. As such, a need exists for real-time detection of these contaminants, within natural gas pipelines, in order to determine contaminant sources and reduce contaminant quantities. In this study, an in-line, non-perturbing, real-time, microwave-based contaminants sensing technology was developed and tested at a natural gas test facility located in Alberta, Canada. The contaminants detector was installed on DN150 pipe and tested over a gas velocity range of 1.3–13.2 m/s. First, glass oxide particles were intermittently injected into the gas stream immediately upstream of the detector. Two different glass oxide particles were tested with particle diameter ranges of 44–88 μm and 88–149μm. Second, liquid contaminant, in the form of compressor lubrication oil, was atomized into the gas stream immediately upstream of the detector. Three types of atomizing nozzles were used in conjunction with liquid injection pumps to test liquid injection rates in the range of 0.07–0.7 L/min. Liquid and solid contaminants were successfully detected using the standard deviation of in-phase and quadrature baseband voltage measurements from the contaminants detector. This paper quantitatively evaluates the solid/liquid contaminants detection performance of this detector in the context of natural gas pipeline applications.
Off-Property Release Likelihood Assessment of Liquid Pipeline Stations Through Barrier Analysis
Authors: Wideman Jeffrey , Sen Millan , Dombroski John , McKechnie Doug 
Published: December 2024

Abstract
Site containment is installed within pipeline stations as a protection barrier that prevents releases from traveling beyond the station boundary. However, with time barriers may degrade, for example berms may wear down due to vehicle traffic, containment valves may fail to close after decades of use, and/or facility patrol intervals may change. Correspondingly, there is potential that offsite release likelihoods may exceed company targets, which is especially pertinent for stations located in high consequence areas. Therefore, a methodology for evaluating the risk of an off-property release at facilities has been developed. This methodology quantifies both asset likelihood of failures, and the effectiveness of leak containment barriers inconsideration of operations (eg. drainage valve opening) and time dependent deterioration (eg. containment berm degradation).
Review of facility drawings was conducted to inventory the station assets and catalogue the station barriers installed during construction. Field visits were then conducted to acquire information on leak barrier condition, berm and containment pond draining frequency due to precipitation events, and flow paths within the facility should a release occur. Subsequently, fault tree analysis was applied to determine the likelihood of off-property release.
Asset specific probability of failures were used to quantify the basic events. Additionally, output gates determined the likelihood of off-property release via AND gates for redundant barriers and OR gates for dependent barriers. The likelihood of off-property release was quantified for each of the overland, spray, and below ground release modes. Environmental consequence was combined with this likelihood, to enable risk assessment.
The methodology has been applied to multiple pipeline operator stations, and mitigations have been executed based on the results. This demonstrates that application of this methodology may identify whether off property release risk and reliability targets are exceeded, enabling informing of decision makers on mitigation priorities.
An Operators Experience in Developing a Technical Strategy for Repurposing the UK National Transmission System (NTS) to Transport Hydrogen
Authors: Senior Gary , Johnstone Steven , Haswell Jane , Jones Corinna 
Published: December 2024

Abstract
National Gas Transmission (NGT) own and operate the 7660 km National Transmission System (NTS) in the United Kingdom (UK) and have a responsibility to develop the green energy system for the future, while delivering the natural gas needs of today.
There is worldwide interest in repurposing existing pipeline transmission systems from transporting methane to hydrogen. Extensive research is being conducted to understand the implications that hydrogen may have on design, materials, integrity and the resulting safety considerations.
The effective application of the developing research requires a robust technical strategy for repurposing that is underpinned by comprehensive technical procedures which address: the data requirements, the technical assessments to be performed and their reporting requirements.
This paper will describe:
- How NGT via Project Union will facilitate an efficient route to net zero and a hydrogen economy by repurposing existing high pressure natural gas pipelines in the NTS to create a hydrogen ‘backbone’.
- The challenges resulting from hydrogen operation.
- The design and construction basis of the UK NTS and how this understanding is being utilized to develop a hydrogen repurposing methodology.
- The Code challenges in hydrogen repurposing.
- A previous ‘change of use’ UK project and its relevance to hydrogen repurposing.
- An outline methodology for hydrogen repurposing of UK pipelines and installations, which takes due cognisance of the hydrogen challenges, Code requirements and the good practice that has previously been experienced in UK ‘change of use’ projects.
- The opportunity for digital transformation when developing and applying a repurposing methodology.
- The ongoing stakeholder challenges for regulators, code bodies, pipeline operators and service providers.
Development and Implementation of Risk-Informed Decision-Making Framework to Manage Corrosion Threat in Gas Transmission Pipelines
Authors: Kohlenberg Derek , Oviedo Fernando , Di Blasi Martin , Hubert Yvan , Yap Keng 
Published: December 2024

Abstract
Quantitative Risk Assessment (QRA) is becoming an increasingly important part of asset integrity management in the pipeline industry, particularly for assets that can be internally inspected using magnetic flux leakage (MFL) in-line inspection (ILI) tools. The application of QRA to corrosion management involves performing probabilistic risk analysis using structural reliability methods which leverage ILI results, corrosion growth rates (CGR), and relevant sources of uncertainties to calculate the probability of failure (POF) and consequence of failure (COF). The risk quantified in terms of POF and COF, and then assessed against a quantitative reliability framework for each corrosion anomaly.
One challenge arises when trying to make integrity decisions considering both the required prescriptive anomaly response criteria with the risk evaluated through QRA. It is common practice for operators to perform an annual QRA for an entire pipeline network, where anomalies found to be of higher risk are selected for risk-informed planning activities as part of the continuous improvement of integrity core process. This can usually happen after the prescriptive responses have been determined and, in many cases, the resulting repair programs have been started. This timeline disconnect in processes has the potential to lead to dig program inefficiencies and missing the opportunity to reduce even further the level of risk in a resource effective way. When compared to the Pipeline and Hazardous Materials Safety Administration (PHMSA) incident data [14] for natural gas pipeline operators, corrosion is the second most pervasive threat behind Third-Party Damage. This shows how industry-wide incorporation of QRA is becoming progressively more important for operators to optimize their risk-informed decision-making with respect to corrosion management.
The purpose of this paper is to provide technical guidance on how to implement an integrated risk-informed decision-making (IRIDM) framework when combining QRA with prescriptive response criteria referenced in the Code of Federal Regulations (CFR) Title 49, Part 192 and the Canadian Standards Association (CSA) Z662:23 to enhance the safety and efficiency of a corrosion management program. The paper will then establish how the proposed integrated risk-informed decision-making framework performs when applied to a hypothetical population of corrosion anomalies on a North American natural gas pipeline network.
Improvements to B31.8 Dent Strain Estimation and Assessment of Dent Formation Induced Cracking
Authors: Tang Huang , Zheng Guanbo , Sun Jialin , Kohlenberg Derek , Di Blasi Martin 
Published: December 2024

Abstract
Local plastic deformation associated with the dent formation can potentially cause ductile damage leading to cracks. Plastic strain is considered as a key indicator to dent formation-induced cracking. The estimation of local plastic strain in a dent is mainly based on the calculation of dent profile curvatures. The ASME B31.8 effective strain equations [1] provide a basis to convert the geometric curvatures into strains.
In this paper, a variety of methods used to estimate dent profile curvatures were evaluated for calculating the effective strain. Hypothetical dent profiles generated from FEA simulations were used for the evaluation. The effective strains obtained by using the B31.8 equations were compared with the FEA results on equivalent plastic strains for all the simulated dent profiles. It was shown that the estimation of plastic strain was sensitive to the methods used for extracting the dent profile curvatures. A method based on the 4th order polynomial curve fitting on a total of 9 points selected near the dent apex was shown to provide more consistent results compared with other methods investigated in the present paper.
Unconstrained dents pose a particular challenge when using the B31.8 effective strain equations to estimate the plastic strain. The measured dent profiles from pipeline inline inspection (ILI) for an unconstrained dent can be significantly different from the indentation dent profiles due to plastic re-rounding. The estimated plastic strains based on the current dent profile after re-rounding with the B31.8 equation display a significant scatter compared with the FEA simulation results. A regression model was developed to improve the strain estimates based on the B31.8 equations using the current dent profiles after re-rounding. The regression model was intended to compensate for the re-rounding and correct the strain estimates from the B31.8 equations by including the current dent geometries and pipe internal pressure. Trained with FEA simulation results for unconstrained dents, the regression equation was shown to significantly improve the strain estimates compared with the FEA results.
A Decision-Making Method for Scheduling of Branched Multiproduct Pipeline Systems Considering User Satisfaction
Authors: Xu Bin , Li Zhengbing , Tu Renfu , Liao Qi , Liang Yongtu 
Published: December 2024

Abstract
In the context of fairness and openness, multiproduct pipeline systems face significant challenges due to the complex market dynamics. There is an urgent need to enhance scheduling technology to improve the system’s service capacity and operational efficiency. In recent years, the scheduling of multiproduct pipelines has been studied extensively. However, most of previous work has focused on meeting the relatively static demands of fixed users, while seldom taking into account the increased demand for more flexible oil receipt times resulting from the addition of users in a fair and open market environment. Therefore, this paper proposes a decision-making method for scheduling of branched multiproduct pipeline systems considering user satisfaction. Firstly, the topological characteristics and the factors influencing user satisfaction of branched pipeline system are analyzed. Then a mixed integer linear programming (MILP) model is established based on continuous-time representation, the model aims to minimizing the penalty cost due to unsatisfied user requirements, and considers the constraints such as batch tracking, contamination control, refinery upload, oil depot download and transfer of junction to obtain a detailed schedule that meets the actual operational requirements of the system. Finally, the proposed method is applied to a real-world pipeline of China. The results demonstrate that the method can generate a schedule that meets the time requirements of multiple users to receive products, which contributes to increased user satisfaction and enhancing the fair and open service level of the system. This provides valuable technical support for the construction of fair and open pipeline systems.
Mechanistic Insight on Intergranular Near-Neutral pH SCC Using Advanced Microscopy
Authors: Long Fei , Zhang Ken , Persaud Suraj , Daymond Mark R. 
Published: December 2024

Abstract
Stress corrosion cracking (SCC) is a major pipeline degradation mode that often leads to leak or rupture during operation or hydrotest. Near neutral pH SCC was initially discovered to form beneath polyethylene-tape coatings in Alberta, Canada in the 1980s followed by reports from American operators. Unlike the well-studied high-pH SCC that is typically intergranular, previous metallurgical examination in laboratory studies suggest that near-neutral pH SCC is predominately wider and transgranular. The crack walls are often corroded heavily which makes studying the crack propagation mechanism challenging.
In this work, advanced electron-microscopy techniques are applied to study the microstructural characteristics of near-neutral pH SCC in ex-service pipeline material. Firstly, 3D tomography of a SCC was carried out on a plasma FIB (focused ion beam), which revealed the development of cracks with a complex network structure from the external surface. Second, careful examination through scanning electron microscopy (SEM) revealed areas containing fine un-corroded cracks along the main path of the heavily corroded crack. To further reveal the characteristics of the fine cracks, through thickness trenches were made by FIB at the areas where un-corroded cracks were observed. The subsequent 2D imaging revealed that the cracks developed along grain boundaries, as opposed to what conventionally is believed i.e., that near-neutral pH SCC develops transgranularly. Lastly, TEM (transmission electron-microscopy) characterization was carried out on FIB lift-outs from the fine un-corroded cracks. Through electron diffraction, the intergranular nature of the fine cracks was determined. The local plasticity was also quantified by comparing the dislocation densities in the grains where fine cracks developed, to the overall dislocation densities in the pipeline. It is shown that no significant plasticity was involved with the development of fine cracks. Lastly, high resolution EDX (energy dispersive x-ray spectroscopy) revealed only oxidation occurred along the walls of the fine cracks, and no distinct foreign elements existed in the developing crack.
The microstructural study revealed that the examined SCC did not require high stress intensity at the crack tip to propagate, which is in-line with the stress analysis based on operational history and bending strain measurement at the locations. Alternative crack propagation mechanisms will be hypothesized and confirmed by in-lab simulated studies.
Influence of Hardness on Hydrogen-Assisted Fracture in Pipeline Steels
Authors: Ronevich Joseph , Agnani Milan , Gagliano Michael , Parker Jonathan , San Marchi Chris 
Published: December 2024

Abstract
To decarbonize the energy sector, there are international efforts to displace carbon-based fuels with renewable alternatives, such as hydrogen. Storage and transportation of gaseous hydrogen are key components of large-scale deployment of carbon-neutral energy technologies, especially storage at scale and transportation over long distances. Due to the high cost of deploying large-scale infrastructure, the existing pipeline network is a potential means of transporting blended natural gas-hydrogen fuels in the near term and carbon-free hydrogen in the future. Much of the existing infrastructure in North America was deployed prior to 1970 when greater variability existed in steel processing and joining techniques often leading to microstructural inhomogeneities and hard spots, which are local regions of elevated hardness relative to the pipe or weld. Hard spots, particularly in older pipes and welds, are a known threat to structural integrity in the presence of hydrogen. High-strength materials are susceptible to hydrogen-assisted fracture, but the susceptibility of hard spots in otherwise low-strength materials (such as vintage pipelines) has not been systematically examined. Assessment of fracture performance of pipeline steels in gaseous hydrogen is a necessary step to establish an approach for structural integrity assessment of pipeline infrastructure for hydrogen service. This approach must include comprehensive understanding of microstructural anomalies (such as hard spots), especially in vintage materials. In this study, fracture resistance of pipeline steels is measured in gaseous hydrogen with a focus on high strength materials and hardness limits established in common practice and in current pipeline codes (such as ASME B31.12). Elastic-plastic fracture toughness measurements were compared for several steel grades to identify the relationship between hardness and fracture resistance in gaseous hydrogen.