bluuebunny/crossref_metadata_2025_split huggingface dataset:
Study on Intelligent Controller Design of Flow Metrological Calibration System
Authors: Yin Xiong , Wen Kai , Wu Yan , Zhou Lei , Gong Jing 
Published: January 2021

Abstract
In recent years, China ramped up imports of natural gas to satisfy the growing demand, which has increased the number of trade meters. Natural gas flowmeters need to be calibrated regularly at calibration stations to ensure their accuracy. Nowadays, the flow metrological calibration process is done by the operator manually in China, which is easy to be affected by personnel experience and proficiency. China is vigorously developing industry 4.0 and AI(artificial intelligence) technologies. In order to improve the calibration efficiency, a design scheme of intelligent controller for flow metrological calibration system is first proposed in this paper.
The intelligent controller can replace the operator for process switching and flow adjustment. First, the controller selects the standard flowmeter according to the type of the calibrated flowmeter, and switches the calibration process. To accurately control the calibration flow for 180 seconds, the controller continuously adjusts the regulating valve with a sequence of commands to the actuator. These commands are generated by intelligent algorithm which is predefined in the controller. Process switching is operated automatically according to flowmeter calibration specifications. In order to reach the required flow point quickly, the flow adjustment is divided into two steps: preliminary adjustment and precise adjustment. For preliminary adjustment, a BP neural network will be built first using the field historical data and simulation results. This neural network describes the relationship between the valve-opening scheme and the calibration flow. Therefore, it could give a calibration flow as close as possible to the expected value during calibration. For precise adjustment, an adaptive PID controller is used. It could adjust the valve opening degree automatically to make sure the flow deviation meet the calibration requirements. Since the PID controller is a self-adaptive PID controller, the process of adjustment is very quick, which can reduce the calibration time largely. After each calibration, both the original neural network and the adaptive function of the controller will be updated to achieve the self-growth.
With the information of the calibrated flowmeter, the entire calibration system can run automatically. The experiment in a calibration station shows that the intelligent controller can control the deviation of the flow value within 5% during 4∼5 minutes.
Kalman Filter and Model-Free Adaptive Control Theory Applied to the Unsteady Flow State Estimation of Product Pipelines
Authors: He Lei , Wen Kai , Gong Jing 
Published: January 2021

Abstract
The accurate online estimation of unsteady flow state provides important operation information for product pipelines real-time scheduling. In practice, affected by the parameter drift and observation noises, traditional estimation methods based on the first principle can hardly provide accurate results within acceptable time. The nonlinear and fast transient characteristics of pipeline flow make it difficult to realize on-line adaptive modification of model parameters. In order to meet the requirements of computational efficiency and accuracy simultaneously, this paper proposes a methodology with two-level adaptive adjustment to realize the digital twin of pipeline nonlinear transient flow process by using simplified linear flow model. In terms of improving computing efficiency, the linear flow model based on frequency response and difference transforming is established to process the on-line state estimation of transient flow. To reduce the deviation between the actual observed value and the linear model estimation, we first introduce mode-free adaptive control method as linear compensation of the reduced order unsteady flow model. The compact form dynamic linearization method has been adopted to design the virtual input of the linear flow model. To further improve the adaptability of the linear model, the model parameters are online adjusted by using the recursive least squares with forgetting factor method. The uncertainty of the model and the interference of observation noise is eliminated by adopting Kalman filter to the state space model based on modified linear model. The effectiveness of the proposed methodology is evaluated by applying to the digital twin process of a product pipeline transient pressure in a multistation pipeline. The results show that the proposed method can make transient pressure estimation of second-order linear model agree well with the value of nonlinear flow model even under unforeseen conditions and noise interference. The performance of the proposed method is better than model-based linear method, data-driven linear method and nonlinear method.
Investigation and Adoption of APGA’s Pipeline Engineer Competency System: The Canadian Experience
Authors: Hill Darren , Ireland Yvanna , Yaremko Jim , Harvey Chris , Sahney Reena 
Published: January 2021

Abstract
With the recognition of demographic change and impacts on the workforce, there is an increased focus on competency management within the pipeline industry. The Canadian Energy Pipeline Association (CEPA) is a voluntary, non-profit industry association representing major Canadian transmission pipeline companies that has been particularly active in this area. With recent publication of CEPA’s guidance document on competency management, CEPA member companies identified a need for a companion set of competency standards for technical staff. As such, the Pipeline Integrity Community of Practice (CoP) within CEPA formed a task group to identify and better understand potential solutions to address this need.
The challenge in maturing competency management within the Canadian pipeline industry, as identified by the task group, is two fold:
1. First, the competency system needs to be flexible to address a broad range of topics, operation types as well as a progression of proficiencies (e.g., engineers in training through to senior level subject matter experts).
2. Second, there is a need for a system that is practical and can be developed / adopted in a relatively short time frame.
In undertaking an assessment of the options available in industry, the adoption of the system that has been developed by the Australian Pipeline and Gas Association (APGA) was selected as the optimal path forward.
The APGA Pipeline Engineer Competency System (APGA PECS) provides a mechanism for understanding competency as well as a means of assessing and documenting competency for pipeline engineers. Specifically, industry expert panels were used to develop the competency standards which were then published for broad consultation prior to finalizing. Within Australia, the system is now the responsibility of the APGA’s Pipeline Engineering Competency System (PECS) Committee for ongoing development, review and maintenance to ensure the system remains current and fit for purpose. One of the key characteristics of the APGA competency standards is the consistency of elements and a standard format for requirements in every stream of pipeline engineering. Further, the APGA System has been demonstrated to be practical and sustainable through use within Australia.
The APGA System is now being customized for use in the Canadian Pipeline industry under an agreement announced in October 2019. This paper will provide insights into key aspects of competency system, the approach taken to assess viable options as well as the experience of customizing the APGA system for Canadian use. The system is anticipated to be available for Canadian companies in 2020 and provides a pathway to meeting the two main challenges identified for managing competency in the Canadian industry.
Continuing Development of Metal-Loss Severity Criteria, Including Width Effects
Authors: Leis Brian N. 
Published: January 2021

Abstract
The emergence in the early 1970s of what about a decade later became the first release of ASME B31G began the development and evolution of criteria to assess the severity of metal-loss defects. Motivated by the desire to reduce the conservatism embedded in B31G, the late 1980s saw the release of Modified B31G, with that same report also introducing RSTRENG, which quantified “riverbottom” effects. The desire to avoid excessive conservatism in their application to higher-strength Grades gave rise to alternative criteria for such applications. PCORRC appeared in 1997, with early versions of DNV RP-F101 and British Gas’ LPC-1 criteria following shortly thereafter. It has since become evident for isolated smooth-bottomed features that in addition to feature length and depth, its width can be a factor, as can its planar shape, and through-thickness profile.
This paper builds on insight gained from the prior work, presenting and validating a Level 1 failure criteria for isolated metal-loss features. The defect-free term for this Level 1 criterion relies on the Zhu-Leis criterion for defect-free pipe failure. That criterion is coupled to a recalibrated defect term analogous to PCORRC, whose extension to include the effects of width is considered. The resulting Level 1 criterion is validated in reference to full-scale tests of pipe with metal-loss, which include a mix of real corrosion and flat-bottomed machined features. These tests consider Grades from Gr B to X100, a wide range of diameters and thicknesses, and in many cases the effect of width. Finite element results are used to illustrate the role of width. Benchmarked against almost 80 full-scale tests it is shown that this new approach affects a reduction in conservatism. At the same time, it provides clear benefits in regard to reduced predictive scatter, as well as a reduction in required maintenance, and the scope of features that must be considered in field-digs.
Pull Test Study of the MFL-A Performance Within Casings to Improve ILI-Based Corrosion Management of Cased Pipes
Authors: Lu Dongliang , Klementis Jennifer , Kariyawasam Shahani , Huang Terry , Sager Ryan 
Published: January 2021

Abstract
High resolution magnetic flux leakage (MFL) in-line inspection (ILI) technology has proven to be one of the most effective approaches to manage corrosion anomalies within the pipeline industry. However, due to the presence of extra metal, pipeline casings are suspected of impacting the detection and sizing accuracy of MFL systems for metal loss features when they are located under casings.
A research project was carried out by TC Energy (TCE) with ROSEN to better understand the effect of pipeline casings on the performance of axially-aligned MFL ILI (MFL-A) technology. The study involved full-scale pull through testing to investigate the effects of various casing conditions and the presence of different types of casing spacers on the inspection system’s sizing and detection performance for corrosion anomalies, including the casing eccentricity, the presence of metallic and electrolytic shorting, and the presence of different types of casing spacers. The testing for various eccentricity and shorting scenarios were compared to an uncased baseline scenario.
An important lesson learned by the project team through this research is the importance of identifying key factors that influence the system performance when analyzing the testing results. Failure in doing so can lead to less meaningful results: in this case, an overly conservative estimate of the sizing performance that does not discriminate appropriately where the system performed well and where the system performed worse than expected. The impact of such a broad-brushing and overly conservative estimate in the MFL system performance to pipeline integrity decisions is very significant and can result in a large number of unnecessary repairs in practice.
With comprehensive data analytics, it was identified that the key factors affecting the tool performance for cased pipes are the small annulus gaps between the casing and the carrier pipe at the feature location, and the presence of certain types of spacers. For the vast majority of cases, the ILI performance under casings is comparable to the performance for uncased pipes. The results from this research suggests that with appropriate consideration of the system performance, TCE’s probabilistic ILI based corrosion management program can effectively manage corrosion anomalies within cased pipes using ILI. Additional research and testing are underway to further support this conclusion.
A Novel Approach for Two-Stage UAV Path Planning in Pipeline Network Inspection
Authors: Qiu Rui , Liang Yongtu 
Published: January 2021

Abstract
Currently, unmanned aerial vehicle (UAV) provides the possibility of comprehensive coverage and multi-dimensional visualization of pipeline monitoring. Encouraged by industry policy, research on UAV path planning in pipeline network inspection has emerged. The difficulties of this issue lie in strict operational requirements, variable flight missions, as well as unified optimization for UAV deployment and real-time path planning. Meanwhile, the intricate structure and large scale of the pipeline network further complicate this issue. At present, there is still room to improve the practicality and applicability of the mathematical model and solution strategy. Aiming at this problem, this paper proposes a novel two-stage optimization approach for UAV path planning in pipeline network inspection. The first stage is conventional pre-flight planning, where the requirement for optimality is higher than calculation time. Therefore, a mixed integer linear programming (MILP) model is established and solved by the commercial solver to obtain the optimal UAV number, take-off location and detailed flight path. The second stage is re-planning during the flight, taking into account frequent pipeline accidents (e.g. leaks and cracks). In this stage, the flight path must be timely rescheduled to identify specific hazardous locations. Thus, the requirement for calculation time is higher than optimality and the genetic algorithm is used for solution to satisfy the timeliness of decision-making. Finally, the proposed method is applied to the UAV inspection of a branched oil and gas transmission pipeline network with 36 nodes and the results are analyzed in detail in terms of computational performance. In the first stage, compared to manpower inspection, the total cost and time of UAV inspection is decreased by 54% and 56% respectively. In the second stage, it takes less than 1 minute to obtain a suboptimal solution, verifying the applicability and superiority of the method.
Now You SCC Me, Now You Don’t: Using Machine Learning to Find Stress Corrosion Cracking
Authors: Smith Michael , Blenkinsop Aidan , Capewell Matthew , Kerrigan Brian 
Published: January 2021

Abstract
Electromagnetic Acoustic Transducer (EMAT) is a non-destructive inspection technology that uses guided acoustic waves to detect planar flaws in a metal structure. When deployed via in-line inspection (ILI), it is an effective way to detect cracks in a pipeline. EMAT has thus become a staple of crack management programs throughout the world since its introduction to the market over a decade ago.
As with all technologies, challenges remain with the inspection process. One such challenge with EMAT is classification. While it is possible to determine that a defect is “crack-like” (a property determined by its tendency to reflect incident waves), it is difficult to determine the nature of the defect from the EMAT measurement alone. Indeed, similar reflections are obtained for many different types of defects, from relatively benign manufacturing and construction abnormalities, to more concerning anomalies such as stress corrosion cracking (SCC).
To compensate for the difficulties in classification, it is good practice to follow up an EMAT inspection with a number of in-field verifications. These investigations allow for a more direct observation of classification and size, and provide valuable information about the nature of cracks. They are, however, expensive — meaning that avoiding unnecessary digs is a top priority.
In this paper, we document a developing approach to post-ILI crack management, whereby the results of an EMAT run are combined with those from field verifications to maximize the amount of information gained from costly field work. This approach — which relies on supervised machine learning — leads to a marked improvement in the classification of crack-like indications from EMAT, and allows future investigations to be prioritized according to the likelihood of finding a concerning defect.
The method was trialed on a pipeline system with extensive SCC, leading to an improved success rate in finding SCC, and a more cost effective crack management plan.
Effects of Biaxial Loading on the Tensile Strain Capacity of Girth Welds With Weld Strength Undermatching and HAZ Softening
Authors: Liu Banglin , Wang Yong-Yi , Chen Xiaotong , Warman David 
Published: January 2021

Abstract
The ability to accurately estimate the tensile strain capacity (TSC) of a girth weld is critical to performing strain-based assessment (SBA). A wide range of geometry, material, and loading factors can affect the TSC of a girth weld. Among the influencing factors, an increase in the internal pressure level has been shown to have a detrimental effect on the TSC.
The overall influence of internal pressure is usually quantified by a TSC reduction factor, defined as the ratio of the TSC at zero pressure to the lowest TSC typically attained at pressure factors around 0.5–0.6. Here the pressure factor is defined as the ratio of the nominal hoop stress induced by pressure to the yield strength (YS) of the pipe material. A number of numeric and experiment studies have reported a TSC reduction factor of 1.5–2.5. These studies generally focused on strain-based designed pipelines with evenmatching or overmatching welds, minimum heat affected zone (HAZ) softening, and a surface breaking flaw at the weld centerline or the fusion boundary.
This paper examines the effects of pipe internal pressure on the TSC of girth welds under the premise of weld strength undermatching and HAZ softening. The interaction of biaxial loading and the local stress concentration at the girth weld region was quantified using full-pipe finite element analysis (FEA). The relationship between TSC and the internal pressure level was obtained under several combinations of weld strength mismatch and HAZ softening. Results from the FEA show that the effects of the internal pressure on the TSC are highly sensitive to the material attributes in the girth weld region. Under less favorable weld strength undermatching and HAZ softening conditions, the traditionally assumed reduction factor or 1.5–2.5 may not be applicable. Further, the location of tensile failure is found to depend on both the weld material attributes and the internal pressure. It is possible for the failure location to shift from pipe body at zero internal pressure to the girth weld at elevated internal pressure levels. The implications of the results for both girth weld qualification and integrity assessment are discussed.
Streamlining the GIS to CAD Workflow for Automated Pipeline Alignment Sheet Generation
Authors: Gurung Gyanendra , Roy Kshama 
Published: January 2021

Abstract
The use of Geographic Information System (GIS) in managing pipeline database and automating routine engineering processes has become a standard practice in the pipeline industry. While maintaining a central database provides security, integrity, and easy management of data throughout the pipeline’s lifecycle, GIS enables spatial analysis of pipeline data in addition to streamlining access and visualization of results. One of the major benefits of GIS integration lies in the ease of automating the alignment sheet generation for pipelines. This paper introduces a simplified pipeline alignment sheet generation workflow using GIS datasets to produce highly customizable alignment sheets in AutoCAD, a much-preferred format in the pipeline industry. By utilizing existing GIS and AutoCAD features to generate the alignment sheet, writing complicated geo-processing or plotting algorithms is minimized, which in turn reduces the risks of committing any systematic errors. This robust and user-friendly workflow not only ensures safety but also leads to a cost-effective solution.
Burst Pressure Prediction of Pipes With SCC Colonies: Development of Intelligent Flaw Interaction Rules
Authors: Wang Bo , Liu Banglin , Wang Yong-Yi , Wang Alex , Rapp Steve 
Published: January 2021

Abstract
Stress Corrosion Cracking (SCC) often occurs in clusters or colonies containing anywhere from a few cracks to hundreds of individual cracks. Multiple closely spaced cracks may interact, resulting in a burst pressure lower than what might be expected from a single crack. Most existing flaw interaction rules account for these interactions by using a single interacting crack to represent multiple cracks when the separations between them are less than a critical spacing. The length of this interacting crack is usually the sum of the individual crack length plus the spacing between them. Using this interacting length and the maximum depth in the colony could produce overly conservative burst pressure predictions which can lead to unnecessary hydrotests and/or other remediation actions.
This two-paper series covers the PRCI-funded work aimed at the development of intelligent flaw interaction rules (termed PRCI-CRES SIA-1-5 rules) that can account more accurately the impact of multiple cracks without being overly conservative. This paper focuses on the development of the rules using numerical analyses. A companion paper covers the evaluation of the rules through full-scale burst tests.
The PRCI-CRES SIA-1-5 rules use the principles of equivalent impact among multiple interacting cracks and represent the magnitude of the impact by a single virtual crack. The new rules do not rely on a critical spacing to determine whether there is an interaction. The magnitude of the interaction is a continuous function of the size of adjacent cracks and the spacing between them.
A large number of finite element analyses (FEA) were conducted to examine the interaction among cracks for many crack configurations, including coplanar and noncoplanar cracks with different sizes and spacings. An analysis process was then developed to use the sizes and spacings of all cracks in an SCC colony to predict the equivalent virtual crack size and burst pressure.