bluuebunny/crossref_metadata_2025_split huggingface dataset:
Study on the Distribution of Submarine Pipeline Corrosion Defects Based on Internal Inspection Data and Data Mining Method
Authors: He Guoxi , Chen Sijia , Liao Kexi , Zhao Shuai 
Published: January 2021

Abstract
Submarine pipelines in the sea are applied for oil, gas, water and mixed transportation. Among them, 91% of the pipes contain CO2. Here, based on the existing pipeline internal inspection data of submarine pipeline, the APRIORI algorithm and least-square-support-vector-machine (LSSVM) are applied to analyze the distribution rules and defect characteristics of internal defects along the pipeline. The corrosion defects are divided into 7 types and the pipeline section is divided into 12 intervals. Also, the pipe segment has been defined as J (general pipe), W (weld) and C (close to weld). The contents include the analysis of the characteristics and types of defects, the distribution of defects along the pipe, the severity of the corrosion defects, the size characteristics of defects, and the comparison of the data detected in multiple rounds. The defect depth of four kinds of pipelines is mostly 10%–20% of the wall thickness, hereby the severity of defects is studied via the percentage distribution of corrosion depth. The data of multi-round inspection shows that the corrosions in the mixed pipeline are active and the defects are increasing. The methods and results in this paper can be employed to predict the most likely defect type, mileage location, clock orientation, and shape size of submarine pipeline corrosion. This is helpful for the integrity management of submarine pipelines.
Large Standoff Magnetometry As a Practical Screening and Monitoring Tool for Pipelines Subjected to Geohazards
Authors: Xu Tianzong (David) 
Published: January 2021

Abstract
Large standoff magnetometry (LSM) as a non-intrusive NDE technology has been used many years in commercial trials for above-ground detection of underground pipeline anomalies associated with stress concentration zones (SCZs). As a passive geo-magnetization flux leakage measurement method, it has been mainly targeting common anomalies such as corrosion, gouges/dents and cracks that are often very localized in small scale. Insufficient consistency and reliability are still the major concern due to technical challenges in getting high resolutions and signal strength at large standoff distance. In comparison, geohazard related external forces induce much large-scale elevated stresses/strains with stronger stress-magnetization signals. Lack of economically viable solutions for pipeline screening and monitoring under geohazard conditions provides a good opportunity to establish LSM’s market position.
This work is part of Pacific Gas and Electric Company’s effort in better fundamental understanding of the state-of-the-art LSM technology and its potential to enhance the current industrial practices of pipeline assessment under geohazard conditions. Specifically, 3D mapping of pipelines including depth of cover (DOC) measurement, locating girth welds and peak stresses/strains with risk rating, verification of strain relief operation and continuous monitoring afterwards. Inline inspection (ILI) and geotechnical analysis data together with field excavation and strain-gauge data are utilized as references to cross-check the LSM results. The outcomes indicate geohazard application is very likely a viable application for LSM technology in near future.
A Coupled Thermo-Hydro-Mechanical Model for Capturing Frost Heave Under Chilled Gas Pipelines
Authors: Na SeonHong , Malekzade Kebria Mahyar , Roy Kshama 
Published: January 2021

Abstract
This paper presents a thermo-hydro-mechanics theory and corresponding computational framework to capture the freezethaw action of frozen porous media and associated frost action under chilled gas pipelines. Based on the mixture theory, frost-susceptible soils are formulated to capture the Darcy flux and thermal actions below the pipelines. Constitutive models that combine the cryo-suction are presented to reproduce the changes in volume, strength, and thermal characteristics of solid grain, pore water, and ice crystal. A generalized hardening rule is adopted to replicate the elasto-plastic responses which strengthens the frozen porous media due to ice crystallization. Changes in permeability and thermal diffusivity are also incorporated by considering the phase transitions of pore water and ice crystal. Numerical examples for pipeline applications are designed to analyze the influence of the freezing and melting process around the pipelines.
Vehicle Load Distribution Under Timber Mats and Flexible Slab
Authors: Zand Benjamin B. 
Published: January 2021

Abstract
Pipeline operators commonly use means of temporary crossing such as timber-mat, airbridge, and slab to reduce surface loading induced stresses in a buried pipeline at locations where a heavy vehicle crosses the buried pipeline. When a temporary crossing has a continuous contact with soil, (e.g. timber mat, flexible slab) load distribution over the ground surface is not immediately known. Load distribution under a timber-mat or flexible slab is a function of the slab to soil stiffness ratio. The load distribution tends to become more uniform with increasing timber-mat or slab stiffness. In this work an analytical model using beam-on-elastic-foundation has been developed and Laplace transform has been utilized to find the solution and apply free-end boundary conditions. The analytical solution can be used for any arbitrary load distribution over a beam-on-elastic foundation. In this work the solution for a point load and a partially distributed uniform load were employed as these scenarios can accurately represent conventional vehicle foot-prints, while being computationally efficient. The analytical solutions are compared to finite element analysis to validate the model. This model can be used in conjunction with the Canadian Energy Pipeline Association (CEPA) surface loading calculator (or similar tools) to analyze pipeline encroachment problems when means of temporary crossing is installed. This model can help the operators determine dimensions and bending stiffness of timber-mat or flexible slab to assure a desirable load distribution will be achieved. The model can also be used for structural analysis of a timber-mat or flexible slab under vehicular load.
Installation Errors in Polyethylene Pipe for Natural Gas Service: Recent Case Histories by the National Transportation Safety Board (NTSB)
Authors: Zakar Frank 
Published: January 2021

Abstract
The National Transportation Safety Board investigated numerous accidents involving the release of natural gas from polyethylene pipelines. The industry manufactures polyethylene pipes and fittings in many shapes and they can be installed/joined in a variety of ways. New grades with improved material properties, such as high-density polyethylene (HDPE) and ultra-high-molecular-weight polyethylene (UHMWPE) have been introduced that show improved material properties compared to their medium-density polyethylene (MDPE) predecessors. However, improved material properties by themselves do not guarantee extended service life of an installed pipe or fitting. Simple errors, whether unintentional, unknown, or unaware by the installer, can lead to a gas leak and possibly a serious accident that causes injury or loss of life. These errors can significantly reduce the service life of a pipe or fitting.
The NTSB Materials Laboratory examined several polyethylene service tees that were involved in an accident as a result of a natural gas leak. Examples of gas leakage resulting from failure to follow best practice at installation will be mentioned. Certain service tee assemblies are joined to pipe segments by mechanical methods while others are joined by fusion methods, such as heat fusion or electrofusion process. An example is cited where a manufacturer of a mechanical tapping tee made several versions of the same design that required specific installation instructions that were different from their predecessors. When several versions of the same tee assembly are manufactured by the same company, one should be aware of identifiable features that differentiate one version from another and then carefully use installation instructions that apply to the model that will be installed. Another example is cited where a service tee that was joined by the heat fusion process had been contaminated prior to bonding.
Learning from mistakes that are made during installation, through examples, provides a foundation from which we can correct our procedures and avoid repeating the same mistakes in the future.
Influence of Steel Chemistry and Field Girth Welding Procedure on Performance of API X70 Line Pipe Steels
Authors: Mohammadijoo Mohsen , Collins Laurie , Rashid Muhammad , Arafin Muhammad 
Published: January 2021

Abstract
Owing to recent concerns regarding pipeline field girth weld performance, particularly heat affected zone (HAZ) softening and toughness, EVRAZ North America has initiated a research program to evaluate the response of API grade line pipe to the current field girth welding practices. In particular, this study aims to elucidate the role of steel alloy design as well as the welding procedure on field girth weld and HAZ properties. This understanding is critical to balance the detrimental effects of HAZ softening on the overall joint strength against factors affecting HAZ toughness. A selection of several different steels with different levels of alloying elements, Ceq and Pcm have been subjected to welding trials to assess the effects of chemistry on joint performance. Furthermore, an analysis on the effect of welding process parameters on the joint properties has been made. The welds, fabricated via a manual shielded metal arc welding (M-SMAW) process, were evaluated in terms of toughness, local vs global strain distribution during tensile testing using digital image correlation (DIC) technique, and hardness contour mapping of the weld and HAZ regions. The results explicitly show that the extent of HAZ softening decreased as the amount of Mo, Mn, Ti/N and Ceq increased. However, this alloying addition resulted in a detrimental effect on the HAZ toughness, particularly towards the cap and fill passes. The HAZ softening increased as the inter-pass temperature and the welding heat input increased. In addition, the strain analysis confirmed the weld passes towards the root/hot passes are more prone to HAZ softening compared with the upper cap and fill passes.
Research Progress of Sand Transport Mechanism and Critical Conditions in Pipelines
Authors: You YuanPeng , He LiMin , Luo Xiaoming , Shi KaiYue , Su JianPeng 
Published: January 2021

Abstract
Sand deposition and transportation in pipelines has become one of the major concerns for flow assurance in petroleum industry. However, research in this field is still in its infancy. This study describes the current development of sand deposition and sand transport in pipeline. The mechanism of particles deposition is described. The effects of particle properties, fluid properties and pipeline structure on the carrying capacity of single-phase and multiphase flow carrying sand are introduced, with emphasis on factors such as particle size, liquid viscosity, flow regime and pipeline inclination. As for modeling studies, the sand transport models can be classified to three categories based on the approach used to develop them: empirical, mechanistic, and semi-mechanistic. The methods for developing and extending models are illustrated in this study. Based on the experimental data, the prediction accuracy of four multiphase models for critical velocity in stratified flow is verified. Further researches should focus on the mechanisms and the establishment of the accurate model for sand flow pattern transformation boundary.
Improved Linepipe Specifications and Welding Practice for Resilient Pipelines
Authors: Wang Yong-Yi , Jia Dan , Warman Dave , Johnson David L. , Rapp Steve 
Published: January 2021

Abstract
At least 10 girth weld incidents in newly constructed pipelines are known to have occurred in North America. More than 30 girth weld incidents in newly constructed pipes have been identified worldwide. A review of the North American incidents identified a few main contributing factors: (1) weld strength undermatching, (2) heat-affected zone (HAZ) softening, and (3) elevated stresses/strains from normal settlement and other loads. Weld bevel geometries of manual welding processes that favor plastic straining along the softened HAZ and low strength root passes were also compounding contributing factors.
Prior publications focused on the industry practices that led to the formation of those contributing factors. This paper covers the enhanced linepipe specifications and improved welding practice that aim to reduce the risk of similar girth weld incidents, thus leading to more resilient pipelines.
The enhanced linepipe specifications include interim recommendations that aim to limit the upper-bound longitudinal strength for a given pipe grade and reduce the linepipe steels’ susceptibility to HAZ softening. The implementation of the interim recommendations is assisted by allowing alternative hoop tensile tests.
The improved welding practice includes (1) the selection of welding procedures, including consumables, that minimizes the likelihood of weld strength undermatching and reduces the propensity for HAZ softening and (2) welding procedure qualification tests and requirements for the production of strain-resistant girth welds.
The recommendations covered in this paper principally target new pipeline construction projects but are also applicable to pipe replacement projects. It is expected that pipeline operators would incorporate the recommendations in their internal procedures and work with welding contractors to execute the recommendations. The improved linepipe specifications and welding practice are expected to increase the resilience of pipelines subjected to realistic construction and in-service loads. The implementation of the recommendations requires changes to some long-standing industry practices and can only occur with collaborative efforts from all stakeholders.
4D Inspection: A Comprehensive Platform to Digitize Pipeline Construction Inspection and Generate Data Driven Continuous Improvement
Authors: Gill Sukhi , Vogt Brett 
Published: January 2021

Abstract
Beginning in 2018, TC Energy began an effort to digitize inspection and construction management and internally named this concept the Dynamic, Digital, Data and Diagnostics platform otherwise known as “4D Inspection”. The 4D Inspection platform is built upon Project Consulting Service’s Epilogue® energy infrastructure construction management solution and is intended to evolve inspection reporting to a digital platform to create standardized construction reporting embedded with real-time compliance validations for efficient and effective management of field construction issues, progress tracking, and over-all construction quality monitoring. Currently, this effort is nearing the end of its first year of a multi-year implementation plan, the platform is in use on projects in both Canada and the United States spanning four different time zones with more than 595 inspectors on over $7.5 billion in capital projects. Even with implementation still underway, this concept’s key functionality, like automated inspection report document control, simplified photo capture with geo-tagging and automated daily progress reporting, has provided immediate benefits of more thorough, more reliable, and more efficient construction data than ever gathered using previous data collection processes. With improved data accuracy and detail, TC Energy gains insight and even foresight into how best to advance construction quality and safety while also impacting overall project costs and schedule.
Management of Ground Movement Hazards: An Overview of a JIP
Authors: Wang Yong-Yi , West Don , Dewar Doug , Mckenzie-Johnson Alex , Rapp Steve 
Published: January 2021

Abstract
Ground movements such as landslides, subsidence, and settlement can pose serious threats to the integrity of pipelines. The consequences of a ground movement event can vary greatly. Certain types of ground movements are slow-moving and can be monitored and mitigated before a catastrophic failure. Other forms of ground movements can be difficult to predict. The most effective approach could be hazard avoidance, proactive means to reduce strain demand on pipelines, and/or building sufficiently robust pipeline segments that have a high tolerance to the strain demand.
This paper provides an overview of a Joint Industry Project (JIP) aimed at developing a best-practice document on managing ground movement hazards. The hazards being focused on are landslides and ground settlement, including mine subsidence. This document attempts to address nearly all major elements necessary for the management of such hazards.
The most unique feature of the JIP is that the scope included the hazard management approach often practiced by geotechnical engineers and the fitness-for-service assessment of pipelines often performed by pipeline integrity engineers.
The document developed in the JIP provides a technical background of various existing and emerging technologies. The recommendations were developed based on a solid fundamental understanding of these technologies and a wide array of actual field experiences.
In addition to the various elements involved in the management of ground movement hazards, the JIP addresses some common misconceptions about the adequacy of codes and standards, including:
• The adequacy of design requirements in ASME B31.4 and B31.8 with respect to ground movement hazards,
• The adequacy of linepipe standards such as API 5L and welding standards such as API 1104 for producing strain-resistant pipelines,
• The proper interpretation of the longitudinal strain design limit of 2% strain in ASME B31.4 and B31.8, and
• The effectiveness of hydrostatic testing in “weeding out” low strain tolerance girth welds.
What Is the Leak Rate for a Liquid Slug Flowing Past a Side Branch?
Authors: Hartloper C. , Clavelle E. , Leong K. , Fitz M. , Epur S. 
Published: January 2021

Abstract
Chemical cleaning is used in gas pipelines to remove debris that was resistant to mechanical cleaning. The cleaner is a liquid mixture of a hydrocarbon-based solvent and a surfactant. It is transported down the pipeline either batched between two cleaning tools or pushed by a single tool.
During a chemical cleaning run, liquid will leak into any side branch it passes. Consequently, gas quality problems may arise when the pipeline returns to regular operations as the leaked liquid hydrocarbons evaporate into the gas stream. Furthermore, operational problems such as flooded separators can occur if a large volume of liquid is lost.
Currently, there is no understanding of what factors influence the liquid’s leak rate into side branches. This paper aspires to address this knowledge gap. A water flow loop was set up to investigate the effect on leak rate of mainline pipe size, side branch pipe size, side branch length, and mainline liquid velocity. The leak rate is found to increase with the side branch pipe size, while remaining unaffected by the mainline pipe size and side branch length. At mainline velocities below the critical velocity, gravitational effects such as the downstream back pressure significantly affect the leak rate. At mainline velocities above the critical velocity these effects disappear, and the leak rate decreases as the mainline liquid velocity increases.
Development of an Optical Angle Sensor With a Mode-Locked Femtosecond Laser Source for Surface Profile Measurement
Authors: Shimizu Yuki , Takazono Shota , Kanda Yuri , Matsukuma Hiraku , Gao Wei , Inaba Hajime 
Published: January 2021

Abstract
Angle sensors based on the laser autocollimation are often employed to evaluate surface profiles of a target of interest. The authors have developed a femtosecond laser angle sensor, in which a spectrometer or an optical spectrum analyzer with a single-mode fiber is employed as the photodetector for simultaneous capturing of the multiple optical modes. In this paper, the concept of the femtosecond laser angle sensor is applied to evaluate the surface profile of a target of interest. An optical setup is designed in such a way that each mode in the spectrum of the mode-locked femtosecond is utilized as the laser beam to measure the local slope of a measurement target at each different point to evaluate the surface profile. Some basic experiments are carried out by using the developed optical setup with a mode-locked femtosecond laser source to evaluate basic performances of the developed optical setup as an optical angle sensor.
Materials Evaluation and Environmental Monitoring Utilizing an Acoustic Resonance
Authors: Tohmyoh Hironori 
Published: January 2021

Abstract
This paper presents the materials evaluation and environmental monitoring techniques utilizing the acoustic resonance, which have been developed by the authors. When the ultrasound passes through thin layer, the transmission and reflection coefficients take their maximum and the minimum values at the resonant frequency. We call this acoustic resonance. The acoustic properties of a polymer film, e.g., the acoustic impedance, ultrasonic velocity, and density, can be determined by observing the acoustic resonance, which occurs at the water/film/reflection plate interface. Acoustic resonance occurs at the reflection plate/film/outer environment interface sensitively changes depending on the outer environment. With use of this, the temperature of the water as an outer environment is tried to be monitored.
Sub-Micrometer Scale Laser Machining Using Position Controlled Photonic Nanojet
Authors: Uenohara Tsutomu , Mizutani Yasuhiro , Takaya Yasuhiro 
Published: January 2021

Abstract
A photonic nanojet (PNJ) is a fine and high intensity light beam that is generated from a dielectric microsphere irradiated by a laser. A PNJ has a smaller beam diameter than the wavelength of the incident laser and can propagate for longer than 1 μm with high intensity and minimal divergence. In other words, a PNJ has a long depth of focus. Due to its outstanding optical properties, PNJ is suitable for laser micro machining. In this paper, we theoretically and experimentally investigated machining characteristics of laser micro machining using a PNJ. First, electromagnetic simulations were conducted to estimate hole diameter when PNJ is irradiated to a sample by changing a distance from the microsphere to the sample. The simulation demonstrated that sub-micrometer scale hole diameter could be obtained even when PNJ is defocused by 1 μm due to the long depth of focus. Next, machining experiments were also conducted on a silicon substrate. A femtosecond laser was used as the machining laser. By holding the microsphere with a micropipette and controlling its position, the position of the PNJ can be controlled in the z direction. Micrometer and sub-micrometer scale hole diameters were obtained even when the position of PNJ in the z direction was changed by 1 μm. The hole diameters obtained in the experiment were consistent with the hole diameter estimated by the simulation. In conclusion, the long depth of focus of a photonic nanojet enable to create sub-micrometer scale structure.