bluuebunny/crossref_metadata_2025_split huggingface dataset:
Investigation of Ultimate Behavior of Elbow Pipes by Tensile Loading Tests in the Direction of In-Plane Bending (Part 2)
Authors: Shimazu Ryuya , Sakai Michiya , Ono Yohei 
Published: November 2024

Abstract
Probabilistic risk assessment is useful in considering the safety of nuclear power plants. To recognize the weaknesses of structures, a realistic fragility assessment must be conducted, for which the failure mode must be set appropriately. In this study, tensile loading tests on full-scale elbow pipes were conducted to enrich the knowledge of failure modes of piping systems. The 150A Sch80 and 200A Sch40 elbow pipes made of carbon steel (JIS STPT410S) finally ruptured at the ductility factors of 38.28 and 34.75, respectively. Aiming at a realistic fragility assessment of ductile ruptures, analytical models that precisely predict the test results were investigated. This study considered that the method of determining the occurrence of ductile failure by comparing the true strain of the rupture and the equivalent plastic strain of the analysis was not appropriate. The low cycle fatigue life prediction model as the summation of the ductile and cyclic damage was considered possible to determine the ductile rupture of elbow pipes. To apply the criteria based on the ratio of the true elongation of rupture and the stress triaxiality squared to the ductile rupture of elbow pipes, the data regarding the material and shape had to be expanded.
Improving Fastening Methods for Threaded Cast-Iron Fittings
Authors: Rivas Allen J. , Elfass Sherif A. 
Published: November 2024

Abstract
Threaded cast-iron fittings find application in a wide array of uses, from residential and commercial natural gas distribution lines to fire-suppression systems. Despite their extensive use, industry standards for mechanically tightening cast-iron pipe-fitting assemblies remain undefined in crucial codes such as the IAPMO Uniform Plumbing Code and the National Fire Protection Association’s NFPA 13.10.3.
The current state of practice, often referred to as the “skill of the craft,” suggests that pipes should be turned 2 to 3 full turns beyond hand-tightening to ensure proper installation. Recognizing this gap in standardization, the research team at the University of Nevada, Reno embarked on a study with the goal of creating a torque chart, akin to those available for bolts.
This study focused on twelve specimens ranging in size from 1 to 2 inches. During the torqueing process, strain within the fittings was closely monitored to determine the appropriate torque levels required for secure assembly.
This paper outlines the methodology adopted for the experiments, examines correlations among various pipe sizes, and delves into the impact of over-torqueing on fitting performance. It also highlights the challenges faced in establishing a standardized torque-based approach to pipe assemblies with cast-iron fittings. Furthermore, the paper introduces an alternative approach to standardization based on the number of unused female threads remaining.
Root Cause Analysis of Expansion Joint Internal Sleeve Failure Under Reverse Flow Conditions Using Computational Modelling
Authors: Harris Chase , Bayram Ahmed , Sanati Mehdi , Harper Chris , Silva-Rivas Jose 
Published: November 2024

Abstract
An expansion joint is a piping component that allows flexibility to absorb thermal and dynamic loads. Many expansion joints have internal sleeves that separate the flow from bellow convolutions. Current EJMA standards do not give detailed guidance on designing these sleeves for reverse flow conditions. An industry design utilizes longitudinal slots in the sleeve to equalize pressure on the inner and outer surfaces. This paper presents a case study to investigate the failure mechanism of this phenomena, verify analytical results with field findings, and suggest a methodology to easily qualify internal sleeves for reverse flow. A combination of Computational Fluid Dynamics (CFD) and Finite Element Analysis (FEA) is used to employ a one-way coupled Fluid Structure Interaction (FSI). The study considers the nonlinear relationship between large deformations, applied fluid pressures, and pressure equalization slot closure. Factors such as flow speed, turbulence profiles, and bellow angulation are varied in this analysis. Results are compared with ASME Section VIII Division 2 criteria for plastic collapse failure and a reasonable limit of flow speed is determined to avoid plastic collapse. This case study may provide guidance for further research and standard development.
Investigation Into the Effects of Cladding in Thermal Fatigue Evaluations of Nuclear Pressure Vessels and Components
Authors: Pellereau Ben , Hockly Meyrick , Reinhardt Wolf 
Published: November 2024

Abstract
Many nuclear components are clad with corrosion resistant material to protect the parent material from the environmental effects of the coolant. Often, the cladding is achieved by weld depositing one or more layers of cladding material to the inside surface of the component; typical cladding materials include austenitic stainless steel and nickel-based alloys.
Rules for the assessment of clad components in Paragraph NB-3122 of Section III of the ASME Boiler and Pressure Vessel Code allow the presence of the cladding to be neglected in analysis provided the cladding is integrally bonded and sufficiently thin.
Different code users appear to have interpreted this exemption in different ways with some neglecting the cladding in both the thermal and stress analysis and others including it in the thermal analysis but neglecting it in the stress analysis and others potentially including it in both, but only assessing the parent material for fatigue. When the environmental effects on fatigue are to be considered, additional questions arise, for example whether the fatigue analysis of the cladding might now become necessary or whether environmental effects need to be considered for the base material.
This paper uses a range of simple finite element models to study the effects of including or excluding cladding from the analysis. Models of typical plant components with a range of cladding thicknesses (between 3% and 10% of total wall thickness with austenitic and nickel-based alloy cladding) are analysed under representative long range and short-range transients. The cladding has been excluded from different stages of the calculation (thermal analysis, stress analysis, fatigue evaluation and application of environmental enhancement factor) and the results from the different assessments are compared to evaluate the different interpretations of the current code rules.
Steps in Application of the Alternative Nozzle Reinforcement Rules for Gasketed Plate Heat Exchangers
Authors: Nikic Milan , Srnic Djordje 
Published: November 2024

Abstract
This paper is a continuation of the work of previously developed alternative nozzle reinforcement rules for gasketed plate heat exchanger (GPHE) end plates. A staged approach has been adopted in the framework of development of the alternative rules. In the first stage, an analytical approach has been utilized using the basis of ASME BPVC Section VIII, Div. 1, Section UG-39, and the principles and data of a simply supported plate theory. In the second stage, Finite Element Analysis (FEA) has been conducted with an aim to expand and refine the alternative nozzle reinforcement rules for GPHE end plates. The philosophy that has been followed in development of the alternative rules assessed the impact of nozzle size and location on bending stresses in the GPHE end plates with the goal to optimize the design thickness of the GPHE end plates. Additionally, the limits of the design approach have been defined.
The objective of this paper is to present application of the alternative nozzle reinforcement rules for GPHE in a concise step-by-step manner. Additionally, the paper will present the geometrical limitations for the application of the rules. Overall, the paper would conclude the work of development of the alternative nozzle reinforcement rules for GPHE by incorporating the results of the previous two stages of the work conducted and published.
Fracture Toughness Test Methods for Material Qualification in Gaseous Hydrogen
Authors: Bezensek Bostjan , Hopkin Sarah , Martin Tom , Guijt Wim , Shie Taylor 
Published: November 2024

Abstract
This paper focuses on the use of a variety of different small scale test methods to assess the fracture resistance of the material in gaseous hydrogen and study susceptibility to subcritical crack growth. The test methods include ASTM E1681 constant load and constant displacement approaches, the ASTM E1820 rising displacement approach and a modified ASTM F1624 with additional fatigue pre-conditioning in a defined manner per the DNV method (also called ‘constant K’ method). The study shows similitude in the threshold toughness results with the methods that do not involve fatigue pre-conditioning. The toughness threshold defined at Δa≈0mm from the rising displacement J-R curve is preferred and gives a similar toughness threshold to the constant load test method. However, when a defined fatigue crack growth is preceding the fracture test the local crack sharpening effect can dramatically reduce the threshold for the onset of stable subcritical crack growth in certain microstructures such as vintage textured ferritic-pearlitic microstructure.
Effect of Temperature on the Crevice Corrosion Propagation on Flange Faces
Authors: Hakimian Soroosh , Bouzid Abdel-Hakim , Hof Lucas A. 
Published: November 2024

Abstract
The corrosion of flange faces poses a significant risk to the structural integrity of bolted flanged connections and can lead to severe leakage problems. It has been observed on multiple occasions that bolted flanged joints experience premature failure due to crevice corrosion on the flange faces, where the gasket is positioned, and these areas are not accessible nor visible. Crevice corrosion occurs due to the breakdown of the passive layer in an occluded area, specifically at the flange and gasket interface, greatly increasing the corrosion rate of the flange compared to general corrosion. The breakdown of the passive layer is a challenging phenomenon, occurring on a small scale and within a short period, making it difficult to detect through regular inspection methods. The propagation of crevice corrosion can be significantly influenced by working conditions. Given that the crevice geometry is one of the most influential factors in crevice corrosion, the specially designed COrrosion Quantification Test (COQT) fixture, introduced in previous papers, is utilized in this research, allowing the application of various electrochemical techniques to assess flange corrosion under a controlled environment. The primary objective of this research is to propose a methodology for measuring and comparing the crevice corrosion propagation rate of flange faces under different temperatures and fluid flow rates. The chemical composition of the flange specimens complies with ASTM A182 F321 stainless steel, while the gasket is a sheet graphite with no inhibitors. The results from potentiostatic polarization tests reveal an increase in crevice corrosion rate with elevated temperatures. Moreover, crevice corrosion rate decreases with the fluid flow rate increase. These findings highlight the influence of mass transport in controlling crevice corrosion propagation rates.
Research on Semi-Empirical Calculation Formula of Bursting Pressure Design of Ultra-High Pressure Bursting Disc
Authors: Yang Chao , Hui Hu , Luo Hui , Bo Ke 
Published: November 2024

Abstract
As a safety relief device for pressure vessel, bursting disc is widely used in various pressure equipment for its simple structure, strong airtightness, large emission capacity, wide adaptability, sensitive overpressure response and other characteristics, which plays an important role in ensuring the safety of pressure equipment in complex environment. With the development of society and economy, pressure vessel is developed towards the direction of extreme and lightweight. In this paper, a semi-empirical formula for calculating the bursting pressure of ultra-high pressure bursting disc design is presented. The non-uniform thinning of the wall thickness after pre-arch deformation of ultra-high pressure bursting disc is measured. The theoretical calculation formula of nonuniform thinning wall thickness after deformation of bursting disc is established based on the hypothesis that the bursting disc is spherical after deformation. In order further simplify the calculation formula and process of semi-empirical formula, test data of different materials, bursting pressure and deflection height are selected to establish the correlation between the deflection height of bursting disc and the strain hardening index of material. The semi-empirical formulations of the designed blasting pressure are simplified, and the numerical simulation and experimental verification of the blasting pressure of the bursting disc are carried out by using experimental method to verify the accuracy of the calculation results of the semi-empirical formula and simplified formula of the designed blasting pressure.
Residual Stress in 347H Weldments: Influence of Various Thermal Treatment on Residual Stress Reduction
Authors: Yang Yi , Gao Yanfei , Feng Zhili , Bunn Jeffrey R. , Payzant E. Andrew , Penso Jorge 
Published: November 2024

Abstract
Residual stresses play a pivotal role in influencing the structural integrity of welded structures, a consequence inherent to the welding process itself. In scenarios involving cyclic thermal and mechanical loading during operation, the dynamic transformation of residual stress patterns arises from multiple influencing factors. In addition to thermomechanical considerations, the evolution of the microstructure significantly contributes to this intricate and interconnected phenomenon. The selection of 347H austenitic stainless steel stands out as an optimal choice due to its exceptional resistance to creep and corrosion. Nonetheless, unforeseen failures continue to pose significant challenges in meeting design criteria. Residual stress remains the primary factor for predicting the lifetime of welded components, and a reliable measurement method for this purpose is still lacking. In this research paper, we present a comprehensive series of measurements conducted on lab-made plate welds subjected to different thermal treatment conditions. Simultaneously, we employ and compare two distinct calculation methodologies to assess the disparities and the feasibility of applying the plane stress methodology to thick service pipe welds. Through a meticulous measurement plan encompassing both As-Welded and post-weld heat treatment (PWHT) lab-made plate welds, which aim to determine the impact of PWHT on the redistribution and relaxation of the residual stress field. Additionally, both plate welds undergo 361.5 hours of thermal aging (TA) at 650°C to mimic as practical as possible service conditions. The validation of both methodologies is subsequently established across four distinct thermal treatment conditions. Consequently, the reliable application of the plane stress methodology to service-grade thin/thick pipes becomes apparent.
Using Computational Fracture Mechanics With the API 579-1/ASME FFS-1 Annex 9H Procedure
Authors: Blanks Daniel 
Published: November 2024

Abstract
The 2021 edition of API 579-1/ASME FFS-1 Fitness-For-Service (API 579) includes a new annex, Annex 9H, which contains a procedure to reduce conservatism in the calculation of the toughness ratio, Kr, in a Fitness-For-Service (FFS) Assessment of a crack-like flaw to API 579 Part 9. The Annex 9H procedure incorporates constraint effects (based on T-stress, a measure of crack front constraint) to improve the fracture toughness, Kmat. Applying Annex 9H reduces the Kr value in the Failure Assessment Diagram (FAD) used to determine if the crack-like flaw is acceptable or unacceptable.
However, the procedure in this annex is limited in its application. Annex 9H can only be applied to surface-breaking semi-elliptical, crack-like flaws in flat plate and cylindrical shell geometries when the stress distribution across the flaw plane can be accurately represented by linearization. Using computational fracture mechanics, the procedure can be expanded and applied to the general case of a surface-breaking, crack-like flaw in a component under any stress distribution.
A procedure is proposed that enables Annex 9H to be implemented in an FFS assessment carried out using computational fracture mechanics three-dimensional (3D) crack meshes with Finite Element Analysis (FEA). This paper details two studies in which 3D crack meshes were created to compute T-stress at the crack front using FEA. T-stress is computed using a linear-elastic FEA and provides the values needed to apply Annex 9H procedures.
Comparisons are made between estimating fracture toughness following the typical Part 9 procedures and those incorporating Annex 9H, with and without computational fracture mechanics. Application of the procedures in WRC Bulletin 590, which provides a method that essentially expands on the Annex 9H procedure for non-linear stress distributions, is also compared. Lastly, the resulting improvement in Kmat, which influences the final FFS outcome, is compared and reviewed. Recommendations are also provided regarding potential additions to the Annex 9H and WRC Bulletin 590 procedures to obtain the most accurate solution.
Fracture Analysis With Residual Stresses From Local Post-Weld Heat Treatment
Authors: Billon François , Jourden Erwan , Miguet Anthony , Moreau François , Willaume Pierre , Mouchette Laurent 
Published: November 2024

Abstract
This study, based on calculations performed by Framatome and ESI Group with ONET Technologies for ONET Technologies Nuclear Pressure Equipment (NPSE) justification, deals with an industrial case which consists of a numerical simulation of a Post Weld Heat Treatment (PWHT) of a butt weld of a Level 1 NPSE and its associated robustness analysis.
The limited local heated length is the source of local thermal gradients in the longitudinal direction because of the existence of transitions between hot and cold parts at the ends of the heated zones.
Temperature repartition in the structure is evaluated thanks to finite element analysis and reconciliation with in-situ temperature sensors by iterative parametric approach to determine the corresponding heat loadings.
These local gradients with high temperature differential generate inelastic deformations (plasticity-creep) and consequently residual stresses in the heat-treated substructures. These residual stresses are considered by combining them with the stresses obtained in operating situations, being the subject of a codified Stress Analysis Report (SAR), in order, in the presence of a technological defect, to calculate its propagation by fatigue (initiation and propagation) and to verify the associated robustness criteria based on the determination of a combined stress intensity factor (KCOMB) being compared to the toughness (KIC).
This robustness analysis is carried out by methods described in AFCEN Codes (initiation as well as propagation according to RCC-M; stability calculation according to RSE-M).
Safety, outcomes, and pharmacokinetics of isavuconazole as a treatment for invasive fungal diseases in pediatric patients: a non-comparative phase 2 trial
Authors: Segers Heidi , Deville Jaime G. , Muller William J. , Manzanares Angela , Desai Amit , Neely Michael , Bordon Victoria , Hanisch Benjamin , Lassaletta Alvaro , Fisher Brian T. , Autmizguine Julie , Groll Andreas H. , Sinnar Shamim , Croos-Dabrera Rodney , Engelhardt Marc , Jones Mark , Kovanda Laura L. , Arrieta Antonio C. 
Published: November 2024

ABSTRACT

Invasive aspergillosis (IA) and mucormycosis (IM) cause significant morbidity and mortality in immunocompromised and/or hospitalized patients. Isavuconazonium sulfate, a prodrug of the antifungal triazole isavuconazole, has been approved for treatment of IA and IM in adults; and was recently approved in children. This study describes the outcomes, safety, and pharmacokinetics of isavuconazole for the treatment of proven, probable, or possible IA or IM in children. In this phase 2, open-label, non-comparative study, patients aged 1 to <18 years with at least possible invasive mold disease were enrolled across 10 centers in the US, Spain, and Belgium from 2019 to 2022. Patients received 10 mg/kg isavuconazonium sulfate daily (maximum 372 mg; equivalent to 5.4 mg/kg or 200 mg isavuconazole) for up to 84 (IA) or 180 days (IM). Outcomes included rates of all-cause case fatality, overall response, treatment-emergent adverse events (TEAEs), and pharmacokinetics. Of 31 patients enrolled, 61.3% were 1–<12 years old; 58.1% had underlying hematologic malignancies. The successful overall response rate at the end of treatment was 54.8%. Day 42 all-cause case fatality was 6.5%; 93.5% experienced TEAEs, and two patients discontinued treatment due to drug-related TEAEs. Dosing at 10 mg/kg (maximum dose: 372 mg) met the pre-defined exposure threshold of above the 25th percentile for the area under the concentration-time curve (≥60 mg·h/L). Simulated doses of 15 mg/kg improved drug exposures in patients aged 1–<3 years. Isavuconazole was well tolerated in children, with exposure consistent with adult studies. Successful response was documented in 54.8% of patients.

CLINICAL TRIALS

This study is registered at
ClinicalTrials.gov
as
NCT03816176
.
Widening the phenotypic spectrum caused by pathogenicPDX1variants in individuals with neonatal diabetes
Authors: Jeffery Nicola , Al Nimri Omar , Houghton Jayne A L , Globa Evgenia , Wakeling Matthew N , Flanagan Sarah E , Hattersley Andrew T , Patel Kashyap Amratlal , De Franco Elisa 
Published: November 2024

IntroductionBiallelicPDX1variants are a rare cause of isolated pancreatic agenesis and neonatal diabetes (NDM) without exocrine pancreatic insufficiency, with 17 cases reported in the literature.Research design and methodsTo determine the phenotypic variability caused by this rare genetic aetiology, we investigated 19 individuals with NDM resulting from biallelic disease-causingPDX1variants.ResultsOf the 19 individuals, 8 (42%) were confirmed to have exocrine insufficiency requiring replacement therapy. Twelve individuals (63.2%) had extrapancreatic features, including 8 (42%) with conditions affecting the duodenum and/or hepatobiliary tract. Defects in duodenum development are consistent with previousPdx1ablation studies in mice which showed abnormal rostral duodenum development.ConclusionsOur findings show that recessivePDX1variants can cause a syndromic form of NDM, highlighting the need for clinical assessment of extrapancreatic features in individuals with NDM caused byPDX1variants.