bluuebunny/crossref_metadata_2025 huggingface dataset:
Evaluation of Geohazards Using a Novel In-Line Inspection Technology
Authors: Koppens Bart , Claassen Rob , Droesen Jan , Cornu Sylvain , Vos Willem
Published: December 2024

The RRP pipeline company operates a network of crude oil and oil product pipelines in The Netherlands and Germany and refined product storage facilities. The oil is transported to refineries in Germany, while other lines transfer refined products sourced from refineries in the Europoort area.

One of the pipelines was known to be subjected to movement due to mining activities which caused land subsidence. Although the mining activities started after pipeline construction, these were foreseen, and considerations were made during the design phase of the pipelines. The conscious decision was made to align the right of way with the mining area, and a system of strain gauges was installed at specific monitoring points. Strain gauges were installed to monitor the influence of the mine on the pipeline and assumed to provide absolute levels of axial strain in more than one hundred locations. Strain gauge data is collected regularly and compared to a model of the pipeline to monitor the influences of ground movement on the axial loading of the line. Pipeline strain relief operations are performed as needed, where the line is excavated, and partially renewed for relaxation.

Although the system continues to work about 60 years after installation, it does not cover the entire length of the pipeline. During regular technical exchanges with NDT Global, the idea was discussed to consider a newly developed technology to measure axial strain by means of ILI tool in pipelines.

Eddy current testing is widely used as an NDE inspection technique for ferrous and non-ferrous materials. Eddy current sensors are commonly used for ID/OD discrimination on MFL tools, and widely known to be most sensitive for diagnosis of surface-breaking defects. The technology is highly mature when deployed in various applications, for instance for pipelines in-ditch inspections during validation activities.

RRP and NDT Global agreed to use the Eddy Current inline inspection strain measurement to capture data for the full length of the line and compare this data to the measurements from the strain gauges installed on the pipelines.

This paper will summarize this validation activity and present the latest effort in developing eddy current for in-line strain measurement in pipelines. The fundamental physical principles will be reviewed, and key parameters considered during the design. Internal validation steps and results will be highlighted. A particular focus applies to the analysis of a known and well-characterized geohazard event.

The authors will evaluate the advantages and disadvantages of the various technologies and discuss how new technologies can be used to improve the integrity of pipelines facing geohazards.
In-Situ Determination of Pipe Body Fracture Toughness Using Planing-Induced Microfracture Method
Authors: Huang Xuejun , Feigel Bryan , Ryan Aidan , Rizwan I Haque Intisar , Willey Brendon , Bellemare Simon C.
Published: December 2024

Pipe toughness determination as part of nondestructive evaluation (NDE) has been sought for decades. Material toughness is needed when analyzing the critical crack size that would fail at MAOP and when performing a fitness-for-service evaluation with cracks discovered during an inspection. When toughness data is not available, operators may use conservative values, perform cut-outs for lab testing, or use other industry-accepted data, such as collected by nondestructive testing. This paper presents a new in-situ, minimally invasive technique to provide pipe body toughness data using the method of planing-induced microfracture. This method involves using a specialized blade featuring a central opening where the material is stretched and fractured instead of being cut, leading to standing residual ligaments on the fractured surfaces of the sample. Characteristics of these ligaments, such as their height, are shown to correlate with the material’s fracture toughness. Preliminary proof-of-concept testing from 30 samples showed that the method could predict KIc to within ±20% of the values derived from destructive lab testing [1]. In the work presented in this paper, a portable prototype instrument has been developed which can create “islands” on a pipe surface and perform the planing-induced microfracture test. This paper will give an overview of the planing-induced microfracture method, the prototype field instrument, and recent test results using the tool.
Non-Destructive Evaluation of Pipe Seam Toughness via Frictional Sliding
Authors: Rizwan I Haque Intisar , Lacy Ryan , Bellemare Simon
Published: December 2024

Several operators have increased the number of pipe cutouts and associated laboratory toughness testing for vintage assets to fill gaps in material records. Original testing certificates did not include fracture toughness, a property that the legacy version of the manufacturing specification did not require. This paper provides a non-destructive evaluation (NDE) approach to pipe seam toughness that can reduce the need for these disruptive pipe cutouts and increase the available dataset for the pipe toughness of specific assets. The NDE approach is currently specific to electric resistance welded (ERW) pipes, but data is provided from a limited proof-of-concept for Electro Flash Welded (EFW) pipes. The current process first estimates the seam’s 85% shear transition temperature in the CVN impact energy vs. temperature curve using the machine learning (ML) model. The predicted transition temperatures are shifted based on American Petroleum Institute (API) API 1176 to account for the difference in strain rate between a CVN test (impact) and fracture initiation (quasi-static). This shifted transition temperature is then compared to the minimum operating temperature. If the operating temperature is higher than the transition temperatures, the pipe material is confirmed to be in the upper shelf region of the CVN impact energy vs. temperature curve. If upper shelf values are applicable, a distribution of CVN toughness values for like samples is used to determine a conservative toughness estimate. A secondary machine learning model can provide an actual estimate of the toughness value.
A Framework for Calculating Life Safety and Environmental Reliability Benchmarks for Highly Volatile Liquid (HVL) Pipelines
Authors: Bandstra Daryl , Dessein Thomas , Moritz Jason , Schwing Aaron
Published: December 2024

The pipeline industry is increasingly utilizing reliability methods as a basis for decision-making when managing the integrity of pipeline systems. Life-safety reliability thresholds for onshore natural gas pipelines and environmental thresholds for low vapor pressure (LVP) pipelines have been published in pipeline standards (e.g. CSA Z662-23, ISO 16708-2006), however limited precedent exists for defining reliability benchmarks for highly volatile liquids (HVL) pipelines which constitute around one third of U.S. hazardous liquids transmission pipeline infrastructure. To address this gap, Flint Hills Resources (FHR) and Integral Engineering (Integral) developed a framework for calculating reliability benchmarks for onshore HVL transmission pipelines to enable FHR to evaluate the performance of their pipelines relative to their industry peers in support of continuous improvement consistent with FHR’s Pipeline Safety Management System implementation. Separate thresholds were developed to address life-safety and environmental considerations. This paper describes the framework and methodology for calculating both life safety and environmental benchmarks at Average and Top Quartile industry historical performances levels.

Elements of the life-safety benchmark framework that will be discussed in this paper include the development of risk benchmarks from PHMSA failure data, the use of a product-specific event tree to consider the potential for different hazardous outcomes, the incorporation of detailed hazard area analysis modelling results, and the use of location-specific geospatial analyses to consider population density and surface conditions.

For the environment benchmarks, this paper describes a statistical analysis of PHMSA hazardous liquids incident data where costs including property damage, emergency response, and environmental remediation were analyzed along with release volume for both LVP and HVL releases. This analysis was used to relate the impact of an LVP release to an equivalent HVL release by adjusting the expected release volume and relative impact per barrel. In addition, the impact ratio, which is a measure of the relative impact of a barrel release in an HCA vs. a Non-HCA location was obtained using the analysis of PHMSA LVP and HVL release cost data.

The result of this study is a framework to calculate Average and Top Quartile HVL life safety reliability benchmarks which consider both individual and societal risk, and HVL environmental reliability benchmarks which consider the relative severity of an HVL release compared to an LVP release.
Mechanical Properties of API 5L X65 Linepipe and Girth Welds Under High-Pressure Hydrogen Gas Environment
Authors: Kisaka Yuji , Kiyokawa Yuki , Kimura Fumiaki , Kawai Yasuhiro , Manabe Keigo , Fujita Shusuke , Shoji Hiroto , Ohata Mitsuru
Published: December 2024

As the world strives to achieve carbon neutrality, hydrogen is potentially expected to become one of the major energy sources. Pipelines can be an efficient method for transporting large quantities of gaseous hydrogen, although the choice of appropriate transport methods depends on the conditions of the hydrogen and the distance of transportation. Some researchers have mentioned that carbon steels, commonly used as linepipe in natural gas pipelines, degrade significantly in a high-pressure gaseous hydrogen environment. On the other hand, it has been reported that in a low-pressure hydrogen environment, the reduction in ductility remains at a practically acceptable level. Furthermore, while some papers discuss the properties of linepipes and longitudinal welds, few papers mention results regarding girth welds. Thus, there is a need to investigate the influence of hydrogen on girth welds. In this study, mechanical properties for API 5L X65 pipes and the girth welds produced by the mechanized gas metal arc welding (GMAW) process were investigated through slow strain rate tensile (SSRT) tests and JIC tests under gaseous hydrogen pressure levels of 10, 20, and 90MPa. Then, the critical weld flaw size was assessed by failure assessment diagram (FAD) in accordance with API 1104.

The SSRT test results show that 0.2% proof stress and ultimate tensile stress did not influence by hydrogen pressure, while elongation and reduction of area decreased at the range of 0 to 20MPa significantly with increasing hydrogen pressure. In addition, K value, calculated from J values obtained by JIC tests were higher than the specified 55MPa • m1/2, value of ASME B31.12. Moreover, the results of the FAD analysis indicate that even if the weld flaw assumed the workmanship flaw size which is 3mm depth and 25mm length exists at the root area of the weld the pipeline should not be failure.
Predictive Analytics Model for Natural Gas Transportation Consumption
Authors: Miranda Rachel , Pedrassani Rafaela , Nogueira Marcus , Arruda Wallthynay , Rodrigues Leticia , Paes Rafael
Published: December 2024

In the current natural gas transportation, operational scheduling heavily relies on daily volume nominations submitted by shippers. However, inaccuracies in these nominations pose significant challenges, leading to imprecise planning and complicating transportation operations.

With the advancement of the Fourth Industrial Revolution, driven by automation and artificial intelligence (AI), revolutions are expected across various industries, promising significant improvements in efficiency, safety, and quality. This study focuses on predicting daily consumption in a natural gas distribution network, utilizing statistical techniques such as time series analysis and regression models. Additionally, advanced Machine Learning algorithms, such as XGBoost, are incorporated to refine predictive capabilities.

The prediction algorithms were developed using the Python programming language. Historical data spanning three years underwent rigorous preprocessing before model training and testing. Key metrics such as Mean Absolute Error (MAE) and Root Mean Square Error (RMSE) were employed to assess the model’s performance, showcasing its superior accuracy in predicting consumption volumes at delivery points compared to the initial nominations received from shippers.

The algorithm encompasses operational data point analysis, outlier handling, hyperparameter optimization, and model tuning. This is followed by integration into the operational engineering and logistics workflow for ongoing operational evaluation. These findings underscore the potential of advanced analytics and machine learning to tackle operational challenges and enhance efficiency and reliability in natural gas transportation.
A Practical Approach to Manage Hard Spot Threat
Authors: Wang Jing , Young Paul S. , Adamski Patrick , Locks Zach , Schulz Lauren , Packard Marc
Published: December 2024

This paper aims at offering a practical, step by step, easy to implement approach to manage hard spot threat in the vintage pipeline system. The approach is the extract of experience and knowledge from daily integrity threat management of hard spot, combining with statistical review of failure data, latest industry new findings, recent PRCI studies and advancement of technology in detection and in-ditch NDE investigation. Quite several leading researchers and scholars have published in-depth study of hard spot, detailed in Research Compendium – Pipe Hard Spot Management PRCI catalog PR-00-22COMP-R02. This paper intends to supplement the past studies with hands-on practice from a ground soldier perspective of how to apply what the industry has known to the daily management.

A hard spot was defined by RIN2 as steel pipe material with a minimum dimension greater than 2 inches (50.8 mm) in any direction with hardness greater than or equal to Rockwell 35 HRC, Brinell 327 HB, or Vickers 345 HV10. It’s been observed that an elevated hardness has often been called and regarded as a hard spot, which could result in reduced efficiency and effectiveness in hard spot management. The priority should be laser-focused on why certain hard spots fail and how to manage them. This paper will share learnings of whether and when reassessment or reanalysis of ILI is required, CP change effect to hard spot stability, soil impact to crack initiation with hard spot, latest ILI tool advancement and field NDE techniques. Recommendation will be provided with regarding continuous improvement and holistic approach to assess hard spot through interactive feature evaluation.
Advanced Surface Loading Stress Analysis Using CEPA Model
Authors: Zhang Shenwei , Yan Zijian (Jason) , Law Jonathan
Published: December 2024

This paper presents methodologies to use CEPA model for conducting advanced analysis of stress on pipelines subject to surface loading under road crossings. The objective of this paper is to address the frequently asked questions (FAQs) including methodology of creating a generic surface loading condition (as opposed to one single wheeled or tracked vehicle), numerical methodology of constructing the live load pressure field using Boussinesq equations for a given generic surface loading condition, methodology of determining the live load pressure on the pipeline at a given crossing angle, automatic methodology of identifying the critical live load pressure from the live load pressure field that develop the most critical stress (i.e., identify the critical location of vehicle with respect to the centerline of pipeline at a given crossing angle), and the methodology of conducting fatigue analysis for girth weld and seam weld under crossing using CEPA model and API 1102. The reported methodology enables better understanding of surface loading stress analysis using CEPA model and benefit pipeline operators to facilitate pipeline integrity management program under road crossings.
A Data-Driven Process to Determine CVN Value Considering Comparable Pipe Attributes
Authors: Zhang Shenwei , Xiang Wei , Maier Clifford , Myden Kyle , SanJuan Riverol Elvis
Published: December 2024

This paper presents a data-driven process to determine the statistical (i.e., probabilistic) characteristics and characteristic value of CVN. The derived probabilistic characteristics and characteristic value of CVN can be used as the input for probabilistic and deterministic crack assessment, respectively. The objective of this paper is two-fold. Firstly, it provides an interpretation of “comparable pipe” specified by 49 CFR § 192.712 e(2)(i)(A) and demonstrates the key pipe attributes for defining comparable pipe. Secondly, it describes the process of determining the characteristic value of CVN as well as the statistical characteristics of CVN using CVN data from “comparable pipe”. To that end, a four-tier protocol to collect CVN data samples from “comparable pipe” is established. For the crack assessment of a particular pipeline segment, the CVN values selected from “comparable pipe” following this protocol embeds necessary conservatism that ensures equivalent or higher safety than the approaches relying on limited CVN data points obtained from that specific segment. The proposed method explicitly considers data variability, reduces statistical bias in determining the characteristic value and is flexible to incorporate learnings from new research as a supplement to this approach. The proposed methodology will facilitate the integrity management program of pipeline with cracks.
Optimized ILI-based Corrosion Management Program Towards a High Reliability Industry
Authors: Zhang Shenwei , Yan Zijian (Jason) , Tse Vincent , SanJuan Riverol Elvis
Published: December 2024

This paper presents the optimization of in-line inspection (ILI) based corrosion management program. Corrosion is often the dominant threat on existing energy pipelines built with low performance coating. ILI-based threat management program is the most successful path to manage time-dependent threats. It has proven to reduce industry wide failure rates but has not always prevented all post ILI failures.

ILI-based corrosion management programs can give very different failure performance and mitigation results depending on the input of key program elements including sizing error of ILI tools, growth rate of corrosion, burst pressure models, safety factors, and assessment methodologies. All these program elements drive higher reliability, cost efficiency through unnecessary cost avoidance, and thus a more efficient program that avoid failures with reduced costs. This paper discusses the optimization of each program element and how these program elements integrate into a system to provide a system optimization that is impactful both on safety and economy.

The improvements made by prudently optimizing each of these program elements is demonstrated through program performance monitoring process and data analytics, which will be beneficial to pipeline industry.
Guidelines for Effective Management of Corrosion Coincident With Seam Welds
Authors: Turnquist Michael , Miglis Yohann , Li Yanping
Published: December 2024

This paper summarizes an 18-month-long research project funded by the Pipeline Research Council International (PRCI) with the primary objective to clarify what analysis methodologies are appropriate to assess corrosion coincident with a pipeline longitudinal seam weld and to support the development of recommended guidelines to effectively manage these types of features.

A critical factor in determining the remaining strength of a corrosion feature intersecting a longitudinal seam weld (LSW) is whether the corrosion is preferential to the weld (often referred to as selective seam weld corrosion or SSWC) or coincident with weld yet no preferential attack of the bondline is occurring. SSWC is a form of corrosion that most often occurs in the bondline of electric resistance welded (ERW) and electric flash welded (EFW) pipe and typically has the appearance of a V-shaped groove. Past research supports that if no preferential attack of the LSW bondline is occurring and the weld has adequate ductility, the presence of the LSW does not reduce the remaining strength of the feature when compared to features not intersecting the LSW, and that industry accepted corrosion assessment models are suitable.

The overall project scope included the execution of destructive testing of corrosion features intersecting an LSW, material property testing of LSWs produced by multiple manufacturing methods, detailed engineering analysis, and a literature review of all past relevant research. This document summarizes each of the above items, as well as the identification of guidelines and criteria to effectively manage corrosion intersecting an LSW.

In addition to the learnings from the project tasks discussed herein, the final guidelines for effective management of corrosion coincident with LSWs consider the susceptibility of the affected pipeline to SSWC and the capability of different inspection technologies (ILI and in-ditch) to effectively identify and characterize potential SSWC. These guidelines will also serve as the basis for recommendations to revise the language of CFR 195.452 and API RP 1176.

The work presented in this paper is part of the PRCI project EC-02-13 “Response to Corrosion Interacting with the Longitudinal Seam in Liquid Pipelines.” This work is being executed in parallel with sibling projects EC-02-12 “Evaluation of Selective Seam Weld Corrosion Susceptibility.” NDE-4-13 “Selective Seam Weld Corrosion Detection with In-line Inspection Technologies.” IM-3-03 “Comprehensive Review and Assessment Guidelines for SSWC,” IM-1-08 “Pragmatic Application of MegaRule RIN 1 - 192.712 Toughness Values,” and NDE-2-15 “SSWC Identification, Sizing, and Measuring Grooving Ratio in the Ditch.”
Two-Phase CO2 Flow Behavior in Horizontal Piping
Authors: Supak Kevin , Bai Fuqaio , Hoffman Eugene , Lu Yingda , Noonan Heath , Witt Kaitlyn
Published: December 2024

Carbon Capture Utilization and Storage (CCUS) technology relies on the cost-effective transport of CO2 between capture and storage/utilization sites in pipeline networks. The presence of anthropogenic impurities can shift the critical point of the mixture and variation in the ambient temperature can significantly alter the transport behavior, including generating multiphase flow. A flow loop was used to gather pressure drop, liquid holdup, and phase distribution of two-phase CO2 in horizontal 3-inch piping. The data were used to compare to industry flow pattern maps and to validate a drift-flux two-phase CO2 model that predicts behaviors of CO2 flow in pipelines. Only stratified, stratified-churn, and dispersed flow patterns were observed for mass flow rates up to 18 lb/s and void fractions up to 50%. The validation results show that the drift flux model has good agreement in both liquid holdup and pressure drop.
Verification of Internal Corrosion Through ILI and Non-Destructive Testing: Lessons Learned
Authors: Westwood Stephen , Ganapathy Bala , Spoering Paul , Zhou Michael , Bolgachenko Taras
Published: December 2024

Verification of In line Inspection results is often challenging for pipelines with internal corrosion, especially in areas of extensive corrosion and/or areas with challenging corrosion morphologies such as pinhole corrosion (as defined by the Pipeline Operators Forum [1]). The most reliable method which many operators choose is to rely on cut-outs for the purpose of both mitigation and ILI verification. However, depending on the diameter and the criticality of the pipeline, verification of internal corrosion features from in line inspection may be based exclusively on ultrasonic (UT) non-destructive examination (NDE). These ultrasonic inspection techniques can range from hand-held pencil probes to automated scanning systems. The output from these methods does vary both in quantity and quality which can and does impact the potential tool validation as per API 1163 [2].

This paper outlines the results from these different inspection techniques and then compares it to laser scan and pit gauge measurements once the inner surface of the pipe wall is available.

This work was done across multiple pipeline diameters and various internal corrosion mechanisms. It reviews the strengths and weakness of the individual NDE measurements and compares them to the original Magnetic Flux Leakage (MFL) inspections from the perspective of validating the inline inspection. An output from this study is a series of guidelines that should be used when verifying internal corrosion that both operators and tool providers can use to determine tool performance. These guidelines help to verify both the ILI tool performance as well as the relevant non-destructive method.
Enhancing Multiphase Flow Computational Performance: A Robust Approach Incorporating Phase Transition Modeling and Dynamic Simulation
Authors: Li Yunchao , Song Shangfei , Kang Qi , Shi Guoyun , Shi Bohui , Wu Haihao , Gong Jing
Published: December 2024

In this study, we enhance the stability of flow prediction in multiphase pipelines by integrating modified source term calculations into the widely used SIMPLE (Semi-Implicit Method for Pressure-Linked Equations) algorithm. We address the challenges faced by traditional two-fluid models, particularly in accurately representing physical processes during operational disruptions such as terrain changes. By incorporating corrective measures into the two-fluid equations, including the continuity equation and momentum conservation equation, we refine the accuracy of flow predictions and mitigate disparities between simulated and actual flow behaviors. Furthermore, we systematically examine and investigate the flow behaviors of multiphase pipelines by amalgamating with the classical two-fluid model. Drawing from practical flow conditions and the foundational principles of conservation laws, we formulate a more universally applicable and theoretically robust mechanistic model. Our approach also involves proposing an innovative method for handling the inter-phase exchange term within the mass conservation equation. The Multiphase Flow Calculation Program (MFCP) is developed as a result of these efforts, enabling comprehensive computational simulations. Through comparative analysis with a commercial multiphase flow software simulator, we validate the computational results, demonstrating computational errors remaining under the 10% threshold. These findings affirm the efficacy of the enhanced SIMPLE algorithm and the theoretical advancements introduced through modified source term calculations and mechanistic modeling. Our study not only contributes to the progression of multiphase flow simulation techniques within the offshore oil and gas industry but also addresses the challenges posed by the rigorous marine environment. By fortifying the stability of flow prediction algorithms and enhancing the efficiency and safety of offshore oil and gas transportation systems, our research facilitates better decision-making in pipeline design, operation, and maintenance. Ultimately, this work underscores the importance of integrating theoretical advancements with practical considerations to advance the understanding and management of multiphase flow dynamics in complex offshore environments.
Study of Innovative Heavy-Gauge Strain-Based 33.0 mm X80 Pipeline Steel Plate and Pipe Designed via Niobium Microalloying
Authors: Zhang Yongqing , Han David , Nie Wenjin , Guo Aimin , Ren Yi
Published: December 2024

In order to be subjected to large displacement, which results in corresponding plastic deformation, the conventional stress-based approach for pipeline design turned to be insufficient for displacement-controlled or partly displacement-controlled load scenarios. As a replacement for a conventional solution, the strain-based pipeline steels were developed to meet the requirements through large plastic deformation. In this study, two heavy-gauge 33 mm (thickest strain-based pipe in the world) X80 pipeline steel plates were designed via niobium microalloying (low carbon and 0.075 wt.% niobium) and selected rolling procedures. The key rolling procedures, including rough rolling start temperature, finish rolling start temperature, final rolling temperature, cooling start temperature and cooling stop temperature, aiming at balanced phases of granular bainite (GB) and polygonal ferrite (PF) as the microstructure of base material, are of crucial importance based on the theory of phase transition, and have been optimized in order to obtain qualified longitudinal performances before and after being aged at 200 °C for 5 mins. Further, the niobium microalloying contributes to the microstructural homogeneity and refined grain distribution through its effective control of solid solution and precipitation.

It is verified through this study and comparison analysis that during the development of innovative heavy-gauge strain-based 33 mm X80 pipe steels, the uniform elongation along the longitudinal direction as well as fracture performance, especially drop weight tear test (DWTT), have been improved to a great extent through optimized rolling procedures.
Steady State Hydraulic and Thermal Simulation Model of Natural Gas Pipeline Network Based on Logistic Regression and Newton Rapson Adaptive Iteration Algorithm
Authors: Chengwei Sun , Lili Zuo , Ming Zhao , Lei Hou
Published: December 2024

Natural gas pipeline simulation technology is the core technology for pipeline management departments to acquire and monitor the operational status of pipelines. It enables managers to observe changes in the pipeline network, thereby improving the safety and reliability of pipeline operations. When solving large-scale and complex natural gas pipeline models using the traditional Newton-Raphson algorithm, issues such as slow convergence speed and low computational efficiency may arise. In this paper, an improved Newton-Raphson adaptive iteration algorithm based on Logistic Regression is proposed. Based on the variation law of iteration error when solving the model using the Newton-Raphson algorithm, an adaptive iteration step size control and convergence judgment mechanism are introduced based on the Logistic Regression function to improve the convergence speed and stability of the algorithm. The improved algorithm effectively improves the solution efficiency while maintaining high accuracy. Computational results show that when using the improved algorithm to solve steady-state simulation models of pipelines of different scales and complexities, it can maintain the same level of accuracy and stability as commercial software SPS. Compared with the traditional Newton-Raphson algorithm, the improved algorithm can achieve an acceleration effect of over 12% in terms of solution time.
Profile Matching for Performance Assessment of Dented Pipe
Authors: Phan Hieu , Dhar Ashutosh , Muntakim Abu
Published: December 2024

In the finite element analysis of dented pipes, an indenter is numerically pushed against the pipe wall to produce a dent profile measured from in-line inspection (ILI). The analysis is repeated until the differences between the calculated and measured profiles (i.e., depths) are less than a tolerance limit. If the differences between the depths are less than the typical ILI measurement tolerance, then the FE profile is assumed to represent the actual profile. ILI tools were reported to measure dent depths with a tolerance of 0.5% and 0.77% of the pipe’s outer diameter. However, many different dent profiles can be developed with depths within the tolerance limit, resulting in different stress and strain levels, that can affect the assessment results. This paper presents an investigation of the effects of different profile shapes on the results of performance assessment of dented pipes. Three-dimensional FE analysis was conducted to simulate the dent on a pipe using the different sizes and shapes of the indenter. The stresses and strains on the pipes with the dent depths within the tolerance are compared. The study reveals that the dent profile created using the depth tolerance criteria may lead to misleading information of the pipe performance.
Incorporating Risk-Informed Methodologies to Complement Deterministic Integrity Decision-Making in the Gas Industry
Authors: Chebaro Mohamed R. , Ji Kai , Safari Miaad , Turney Danielle , Hildebrand Mike R.
Published: December 2024

This paper illustrates the practical application of risk-informed methodologies to complement existing deterministic methods for managing the integrity of gas-carrying assets. This approach aims to enhance the understanding of uncertainty and its role in decision-making while offering a supplementary lens for managing asset condition. It can be particularly relevant when managing the safety and reliability of hydrocarbon-carrying assets in an evolving energy landscape, where additional quantification and justification may become necessary for driving toward optimized remediation or replacement decisions.

Historically, deterministic methods were generally sufficient to inform decisions when managing asset integrity threats. Though such approaches remain relevant, they can present limitations, especially when effective systemic prioritization is required for complex systems encompassing dissimilar assets, such as distribution and transmission piping, various facilities, and underground storage assets. More advanced data-driven models utilizing multiple risk assessment techniques can benefit operators in these cases, particularly as more industry codes and standards evolve accordingly.

The authors of this paper highlight how they successfully adopted this approach in the Integrity Department at Enbridge Gas Inc. (EGI) in Ontario, Canada. They do so by describing the team’s comprehensive decision-making lifecycle and providing practical illustrations of how risk-based evaluations were layered over deterministic outcomes to better define asset condition and optimize mitigation strategies. In their first case study, they examine the overlay of the two approaches for an urban distribution network servicing tens of thousands of natural gas customers. In this illustration, incorporating and quantifying data uncertainty in probabilistic computations results in divergent conclusions between the two assessment streams, an outcome explored in the paper. In their second example, the authors describe a recent application of probabilistic risk evaluations following traditional deterministic analyses of axial and circumferential magnetic flux leakage (MFL-A and MFL-C) in-line inspection (ILI) data on a transmission pipeline. Finally, they present a third application to exemplify the interconnectedness between the deterministic and risk methodologies when prioritizing integrity decisions on underground gas storage assets. The advantages and disadvantages of each method are discussed to underline the criticality of using both approaches concurrently to optimize the comprehensiveness and effectiveness of decision-making.
Advancements in Continuous Corrosion Monitoring Technology for Pipeline Integrity Assessments
Authors: Li Xingman Wendy , Anderson Toby , Kindel Samuel
Published: December 2024

This paper introduces a technological innovation in continuous corrosion monitoring, specifically focusing on a novel approach inspired by guided wave testing. The developed technology, referred to as gPIMS, operates on the same underlying principles as guided wave testing but distinguishes itself by offering continuous monitoring capabilities. This is achieved through the use of permanent collars on pipelines, integrated into a system capable of automated data collection and upload to a cloud-based data management and visualization software. The information is delivered directly to desk, providing engineers with the tools to obtain a nuanced understanding of corrosion dynamics.

The primary emphasis of this paper lies in presenting the application of this technology in a real-world scenario through Enbridge’s first field deployment of gPIMS. The study encompasses critical aspects such as site selection criteria, the field installation and commissioning process, and an in-depth data comparison between gPIMS and traditionally acquired guided wave testing data. Furthermore, the paper delves into the long-term cost-effectiveness of utilizing continuous corrosion monitoring technology in comparison to other threat assessment methods, and how the data derived from continuous monitoring can dynamically drive the qualitative risk analysis.

By focusing on the technological advancements and their implications, this paper contributes valuable insights to the ongoing discourse on enhancing the cost efficacy of corrosion monitoring and wide future applications in pipeline integrity management.
Effects of Axial Stress on Burst Strength of Corroded Pipes
Authors: Tao Gang
Published: December 2024

Pipes in service are often subjected to in-situ axial stresses in addition to the pressure loading. These additional axial stresses are known to affect the burst strength of uncorroded pipes. Therefore, it is expected that the burst strength of corroded pipes also has a dependency on axial stresses. However, incorporating the axial stress effect in burst strength assessment models for corroded pipes is much more challenging than for uncorroded pipes, due to the significantly increased difficulty in analytical characterization of the complex stress and strain distributions within a corroded pipe. Although methods for treatment of axial stresses in remaining burst strength models are available in a few industry codes, it appears that investigation of the applicability and accuracy of these methods is limited.

Adopting a recently proposed and validated plastic instability-based failure criterion, Finite Element Analysis (FEA) was performed on previously tested pipe samples to investigate the effects of axial stress on burst pressure of corroded pipes. In general, the axial stress was found to have an insignificant impact on the burst pressure of pipe samples with localized corrosion in this study. An in-depth investigation of the stress and strain response within the corrosion region revealed that the constraint effect of the surrounding uncorroded pipe body greatly reduces the axial stress effect on the burst pressure of pipes with localized corrosion. This finding poses a question to the assumption of the proportional relationship between the stresses within the corrosion region and uncorroded pipe body adopted in the burst strength assessment models in some industry codes. The outcome of this study proves the need for future research to improve the methods to account for the axial stress effect in burst pressure prediction for corroded pipes.
Replacement of 8-Inch Gas Transmission Pipeline With Smartpipe® Composite Liner in Roanoke County, Virginia
Authors: Vazquez Claudia S. , Strachan Kirk , Baraniecki Kurt , McIntosh Robin , Lee Liang-Hai , Nemeth Alex
Published: December 2024

This paper provides an overview of Enbridge Gas Transmission and Midstream’s PHMSA special permitted project to install and use Smartpipe® to retrofit 0.64 miles of an 8-inch diameter, 1965 vintage steel pipeline, known as the Line 3320A-100. The new 6.25-inch internal diameter (ID), 7.6-inch outer diameter (OD) Smartpipe® was inserted through a small segment of the existing 8-inch diameter steel pipeline, which improves pipeline integrity and safety by eliminating corrosion and increasing resistance to third-party damage. Smartpipe® also significantly reduced the environmental impact and disturbance associated with the excavation, earth disturbance, and other activities that would have been necessary with removal of the existing 8-inch diameter steel pipeline and the installation of a new steel pipeline in the right of way (ROW). In addition to an overview of the engineering design and construction of the project, the short- and long-term use case of the Smartpipe technology over traditional materials is explored.

Smartpipe® offers a high strength composite pipe liner solution that involves a trenchless installation within the existing steel line to minimize disruption to both operations and the environment. Embedded fibre optics within the Smartpipe® offer real time leak detection monitoring capabilities and ROW activity real time monitoring along the entire length of the pipe. This ESG centric solution not only provides a reduction in carbon footprint when compared to traditional construction methods (open trench pipe replacement and horizontal directional drill replacement) and it is designed to address high consequence and difficult to access areas where operator systems may pass through. Smartpipe® has high pressure capabilities to provide repurposing opportunities for aging, derated and abandoned pipe assets. Smartpipe® is DOE tested for hydrogen use and compatibility with CO2 to provide a bridge to future energy sources. This study serves as a valuable case for industry professionals, offering lessons learned, a PHMSA special permit application template for Smartpipe® replacements as well as education and knowledge on the Smartpipe® technology and installation considerations.
Method for Establishing a Default Toughness for DSAW Long Seam Welds
Authors: Riccardella Scott , Al-Hasani Zain , Moran Sean , Ostahowski Dan , Molina Jose , Maier Clifford
Published: December 2024

Double Submerged Arc Welded (DSAW) longitudinal seam welds have typically experienced fewer failures and demonstrated a greater level of reliability than other seam weld types (such as vintage Electric Resistance Welded (ERW) pipe). Given the greater reliability of DSAW seam welds, a higher default toughness is warranted when evaluating pipeline defects. This paper provides a comprehensive review of two pipeline operators’ systems, demonstrating that improved pipe manufacturing techniques such as DSAW pipe have significantly higher Charpy V-Notch (CVN) impact energy values for the longitudinal seam weld metal and heat affected zone than the default values prescribed in 49 CFR 192 to be used for all seam weld types. In accordance with pipeline safety regulation, these operators have proposed to use alternative, but conservative, default toughness values when performing Predicted Failure Pressure (PFP) analyses of crack or crack-like defects in DSAW long seam welds. This paper provides a summary of the results of the systemwide review for two major North American pipeline operators and details the process used to complete the statistical analysis to develop alternative default toughness values for DSAW seam welds.
Proper Probabilistic Characterization of Uncertainties and its Impact to Reliability-Based Pipeline Integrity and Risk Management
Authors: Lu Dongliang , Dessein Thomas , Bandstra Daryl , Ayello Francois
Published: December 2024

Reliability-based integrity and risk management requires explicit consideration of various uncertainties in the modelling and decision-making process. In the case of likelihood of failure estimation of individual defects, the main uncertainties involved include uncertainties associated with the physical properties of the pipe, uncertainties associated with defect dimension and the model uncertainty associated with burst pressure calculation. In the case of likelihood of failure and risk analyses for segments with a large number of defects, additional consideration to aggregation of uncertainties from a joint or defect population is needed.

The current industry practice for the reliability-based assessment often takes a simplified approach on the probabilistic characterization of various uncertainties and the aggregation of uncertainties, resulting in inaccurate and often conservative estimation of likelihood of failure and risk. The objective of this study is to through examples illustrate how proper probabilistic characterization of uncertainties can be constructed and its impact to reliability-based integrity and risk management. Specifically, this study investigates characterization and modelling of burst pressure calculation error and probabilistic modelling of additive measurement error. The influence of different assumptions and probabilistic representations of the uncertainties to the estimated likelihood of failure for individual defects and a defect population on the segment is examined. The results from the study demonstrated the importance of proper probabilistic characterization of uncertainties in reliability-based integrity management and risk assessment and hopefully open discussions on further improvements in this area in the industry.
Interpretation of the Safety Risk Tolerance Criteria for Integrated Asset Management of Pipelines
Authors: Koduru Smitha D.
Published: December 2024

Safety risk tolerance criteria are commonly established using the risk measures for individual risk and societal risk. Several studies on the review of international standards for safety risk acceptance criteria have identified that in most international standards, the societal risk criterion is expressed in terms an F-N curve where N is the expected number of fatalities due to hazardous conditions posed by an infrastructure element and F is the estimated frequency of N or more fatalities. The Netherlands and the UK have pioneered establishing the risk tolerance criteria for both individual and societal risk. The development of the safety risk tolerance criteria was primarily in the context of regulatory decision-making for the permitting process of the facilities, which was later expanded to include hazardous materials transport and pipelines. For the existing facilities and pipelines, the risk tolerance criteria are used extensively for land-use planning and development.

Recently, Canadian standard, CSA Z662:2023 “Oil and Gas Pipeline Systems” has included quantitative risk criteria for pipelines in the informative (non-mandatory) Annex B portion that is applicable for the risk management of all aspects of the pipeline life cycle. Following the established international norms, the individual and societal risk criteria were published such that the societal risk criterion for the F-N curve to be applied over one kilometer of the pipeline. In contrast to the international standards such as IGEM/TD/2 “Assessing the risks from high pressure Natural Gas pipelines” (2015), there is little guidance to differentiate between use of the quantitative safety tolerance criteria for the purpose of permitting of new pipelines and land-use planning with the purpose of pipeline integrity management.

This paper presents the differences in the use of available quantitative safety risk tolerance criteria for land-use planning and the pipeline risk management during the pipeline life cycle. The applicability of the risk tolerance as intended during the development of criteria, is critically reviewed when used in the context of risk management for the integrated asset management of the pipeline considering the life cycle performance. Additional considerations for interpreting the safety risk tolerance criteria during decision-making regarding risk mitigation actions are proposed. Furthermore, linear metrics used in risk measures established for other linear infrastructure, such as roads, and railways are compared with pipelines, and the differences between risk measures to establish tolerance criteria for point-source hazard infrastructure, such as chemical facilities, with the linear infrastructure, such as pipelines are highlighted.