bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evolution of Thermoelastic Stresses in a Finite-Width Slab or Thick Cylinder With a Growing or Receding Boundary
Authors: Kumar Pavan , Segall Albert , Drapaca Corina 
Published: November 2024

Abstract
Semi-analytical thermoelastic stress solutions for a single phase, homogeneous, and finite-width slab or thick cylinder with a constant-velocity growing or receding boundary under Unit-Loading were derived. Initially, a semi-analytical solution for the heat equation for a slab with a growing or receding boundary was derived in the Laplace domain and a series representation then used to approximate the inverse Laplace transformin the time domain. Conformal mapping was then used to transform the slab solution to an annulus. The resulting semi-analytical solutions were then used with established integral elasticity-equations to determine the resulting transient stress-states. All solutions allow for convection on the fixed boundary that is the opposite side for a plate and outer radius for the cylinder. Once derived, the semi-analytical stress predictions were compared to finite-element simulations with excellent agreement. Given the changing thickness, both the thermal and stress-states cannot reach true steady-state equilibrium, especially for faster growth or recession rates. Indeed, the temperature states and resulting stresses become somewhat linear with respect to time, reflecting the constant velocity of growth or recession. In practice, the resulting solutions can be used to determine transient stresses during machining, wear, erosion, corrosion, and/or additive manufacturing, especially for lower temperature solid-state methods such as cold-spray.
EAF, Transferability to Operation and Improving Prospects
Authors: Solin Jussi , Seppänen Tommi 
Published: November 2024

Abstract
Environment assisted fatigue (EAF) research in simulated reactor coolant waters has shown variable reductions in fatigue lives of laboratory specimens. Unless otherwise shown, the results are assumed transferable to the pressure boundaries of primary coolant circuits. By experiments and regression analysis determined environmental penalty factors have been adopted as means to adjust the allowable numbers of fatigue transients in reactor components. These Fen factors play a central role in transfer of EAF lab data to fatigue management and risk informed inspection at the plant.
This paper reports lessons learned in experimental and analytical research of EAF aiming to understand and reliably measure Fen factors for improved transferability to the codified fatigue assessment of stainless reactor components.
We have earlier reported inability to repeat the Fen factors proposed for the conservative high temperature & low-rate edge, when applying direct strain control in PWR water. This issue and ongoing research aiming to develop improved Fen models will be addressed. In addition, a thermodynamic point of view is introduced and discussed. The thermodynamic model fits poorly to the lowest Fen factors for low temperatures and/or high strain rates, which is probably also an area not well supported by experimental data but may still be relevant in PWR operation.
Challenges in determining Fen factors, their transferability to plant operation and possibilities for improvements will be discussed.
Simplified Elevated Temperature Service Elastic Methods for Section III, Division 5 Class A Metallic Pressure Boundary Components
Authors: Pease Derrick 
Published: November 2024

Abstract
The goal of this paper is to provide simplified elevated temperature service elastic stress evaluation methods and criteria that are numerically identical to the current ASME BPVC Section III, Division 5 rules but in a form that is easier to understand and apply. For the most part the elastic rules and methods have remained the same since their original development in the mid to late 1900s. The current rules cover several elastic evaluation criteria based on gross inelastic deformation, progressive inelastic deformation, and creep-fatigue damage as well as some limited buckling rules. Gross Inelastic deformation rules include time-based use-fractions which can be simplified by defining specific load stress intensity nomenclature and values used to lookup allowed durations from the time-dependent material curves. Significant creep ratcheting Test No. A-1 and A-2 can be combined and simplified by comparing a total stress intensity to a significant creep stress intensity limit. Negligible creep ratcheting Test No, A-3 can be simplified by defining a negligible creep stress intensity range limit based on the sum of the portions of the stress limit associated with the temperatures at cold and hot extremes of the stress cycle. Fatigue and creep rules include multiple methods for determining damage. Clarification of the different methods is included to provide a graded approach in determining fatigue and creep damage. For fatigue damage, several of the parameters used to determine the modified maximum equivalent strain range can be simplified.
A Multi-Scale Minimum Time-To-Failure Reliability Model for Creep, Creep Crack Initiation, and Creep Crack Growth of a 2-1/4-Cr-1-Mo Steel at 565 °C and a BK-7 Glass at 20 °C
Authors: Fong Jeffrey T. , Freiman Stephen W. , Cohn Marvin J. , Heckert N. Alan 
Published: November 2024

Abstract
The American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code (BPVC) Committee has recently developed a new Section XI (Nuclear Components Inspection) Division 2 Code named “Reliability and Integrity Management (RIM).” RIM incorporates a new concept known as “System-Based Code (SBC)” originally due to Asada and his colleagues (2001–2004), where an integrated approach from design to service inspection is introduced using three new types of statistical quantities: (1) “system reliability index,” or “system co-reliability target” for any system consisting of structures and components, (2) “structural co-reliability,” for any structure, and (3) “component co-reliability” for any component, where co-reliability is defined as “1 – reliability” and is equal to failure probability. In a recent paper published in the International Journal of Pressure Vessels and Piping (Vol. 173 (2019), pp. 79-93), Fong, Heckert, Filliben, and Freiman developed a new theory of fatigue and creep rupture life modeling for metal alloys and brittle materials at room and elevated temperatures such that the co-reliability of a smooth component can be estimated from fatigue and creep rupture test data with simple loading histories. In this paper, we extend the theory to include a methodology to estimate the failure probability (or, co-reliability) of a 2-1/4-Cr-1-Mo ferritic steel component undergoing a loading history of creep, creep crack initiation, and creep crack growth at 565 °C, and a brittle material such as BK-7 glass undergoing dynamic fatigue at 20 °C. To illustrate an application of this new modeling approach, we present a numerical example using (a) the experimental test data of 2-1/4-Cr-1-Mo ferritic steel in creep at 565 °C as published by Kilian Wasmer in his Ph.D. thesis (Imperial College London, 2003), (b) the experimental test data of 2-1/4-Cr-1-Mo ferritic steel in creep crack initiation and growth at 565 °C also by Wasmer (Ph.D. thesis, 2003), and (c) the experimental test data of 35 specimens of BK-7 glass loaded to failure at a range of constant stressing rates at 20 °C (in an unpublished laboratory report by Freiman, Fuller, Quinn, Quinn, and Carter (1993)). The significance and limitations of this new damage-state-based approach to modeling creep and to estimate the component failure probability (or, co-reliability) of steel and brittle components in creep and fatigue are discussed with the addition of a new example case of the simple fatigue loading of an AISI4340 steel at a stress amplitude of 282 MPa in Room Temperature.
General Elastic Analysis on Atmospheric Liquid Storage Tank
Authors: Zhao Mingxin 
Published: November 2024

Abstract
A study is presented to analyze atmospheric liquid storage tank using the general elasticity theory. The tank is modeled as axisymmetric structure with a cylindrical wall and a flat floor at bottom subject to hydrostatic pressure. Deformation is derived from the complete solution form of the governing differential equation. Different boundary conditions at the bottom of tank wall, including free, fixed, and elastic, are examined. The corner joint between the tank wall and floor is investigated using elastic plate theory. Equivalent torsional and radial springs at the corner joint are generated as the elastic constraints for the tank wall. Further, the solution equation is expanded for the general condition of tank wall, which consists of multiple shell courses with different thicknesses. The expanded solution equations are obtained using the compatibility conditions by assuming continuity and smoothness between adjacent shell courses in equilibrium state. In addition, the equations are transformed into modular matrix equation form for each pair of adjacent shell courses, and the top or bottom constraints of the tank wall. All modular matrix equations are assembled to form the complete matrix equation for the entire tank wall for computational implementation.
Construction Rules, Preservice Inspection Rules, and Nuclear Safety
Authors: Benson Michael , Honcharik John , Rudland David 
Published: November 2024

Abstract
Construction of nuclear sites is an important topic, as governments and utilities are seeking to decarbonize. The rules governing construction and preservice examination play a vital role in providing stakeholder confidence that safety-related nuclear components will perform their intended function under normal operating and accident conditions. Construction rules provide sound fabrication procedures, while preservice examination provides an important verification step prior to placing the finished component into service. This paper reviews the construction and preservice examination rules for U.S. nuclear plants and discusses how they interact.
Effect of Temperature on the Fatigue Crack Growth Rates of Austenitic Stainless Steels in an Air Environment for ASME Code Section XI
Authors: Morley Andrew , Negyesi Martin , Hasegawa Kunio 
Published: November 2024

Abstract
Fatigue crack growth rates da/dN for stainless steels in air environment are provided by the ASME Boiler and Pressure Vessel Code in Section XI. The fatigue crack growth rates are given by da/dN = CF(ΔK)n, where CF is the fatigue crack growth rate coefficient, n is the fatigue crack growth rate exponent and ΔK is the stress intensity factor range. The coefficient CF consists of a temperature parameter, ST, and a scaling parameter, SR, which is a function of the stress ratio, R.
A function for the ST parameter is given in Appendix Y of ASME Code Section XI: ST=10[−8.714+1.34×10−3T−3.34×10−6T2+5.95×10−9T3] where T is the temperature in °C.
However, the functional form is cumbersome and the original basis for the temperature function is questionable, consisting mostly of testing outside of the bounds of the temperatures of interest to its application in ASME Code Section XI Appendix Y.
Following a review of the literature for test data at temperatures more directly relevant to the Code, the function of the temperature parameter is reviewed. An alternative equation for ST for stainless steels in an air environment is proposed for ASME Code Section XI Appendix Y, based on the literature experimental data surveyed in this study.
An Investigation of Stress Intensification Factors of Laterals Compared to Tees
Authors: Rathinasabapathy Mohan , Rivas Cristobal 
Published: November 2024

Abstract
In 2018 and prior versions of ASME B31.3 code, Appendix D provided Stress Intensification Factors (SIFs) and Flexibility Factors (also known as k-factors) for elbows and 90-degree branch connections (i.e., tees), but not for laterals. In the 2020 version of ASME B31.3 code, Appendix D was replaced by ASME B31J 2017 for SIFs and k-factors of various piping components. ASME B31J 2017 Note 7 states that laterals, which are reinforced fabricated, unreinforced fabricated, contoured, or branch welded-on fitting (weldolet) connections may use the same SIFs as their corresponding 90-degree branch connections provided the following conditions are met: Branch pipe axis normal to within 45 degrees of the header surface, D/T &lt; 50, d/D ≤ 0.6, itb taken equal to iob.
“Normal to within 45 degrees” may be interpreted as less than 45 degrees, while the intent of the code may be to include the 45-degree laterals, which are the most common in the industry. This paper investigates whether the SIFs of above mentioned 90-degree branch connections can be used for corresponding 45-degree branch connections based on Finite Element Analysis (FEA). In addition, this paper explores the validity of D/T and d/D limits, and if they can be extended.
Assessment of ASME VIII-1 UG-20(f) Using Fracture Mechanics Per API-579-1/ASME FFS-1 (2021)
Authors: Finn Thomas P. , Hay Clifford A. , Bedoya Julian J. , Pioszak Greger 
Published: November 2024

Abstract
Paragraph UG-20(f) of the ASME Boiler and Pressure Vessel Code (BPVC), Section VIII, Division 1 provides guidance on applicable impact test exemptions for design temperatures no colder than −20 °F (−29 °C) under certain conditions (e.g. material/thickness combinations; hydrostatically tested; no shock loadings). Functionally, this paragraph allows for design at temperatures colder than UCS-66 permits for equivalent material/thickness combinations without the requirement for impact testing.
A similar provision to UG-20(f) was included in Part 3 of API RP 579 (2000) and in API-579-1/ASME FFS-1 (2007); however, it was removed in the 2016 edition of API-579-1/ASME FFS-1 and has not been reintroduced in subsequent editions.
This study reviews the requirements of UG-20(f) using the fracture mechanics perspective from the latest (2021) release of API-579-1/ASME FFS-1. The provisions in API-579-1/ASME FFS-1 (2021) for considering constraint effects (Annex 9H) and crack front integration (Annex 9I) are included in this analysis so that the magnitude of their effects can be understood. Since UG-20(f) requires a hydrotest for most situations, a review of the warm pre-stress effects per Annex 9F is also included. The results of this study indicate that an update to the current thickness limitation for Curve B materials is recommended.
No recommendations for the overall disposition of paragraph UG-20(f) are provided in this study; however, it is anticipated that the analysis contained herein could assist various Standards Development Committees in decisions related to potential future updates.
Evaluation of Service Removed HP40-Modified Reformer Tubes and Development of Multi-Axial Pressurization Testing in Full-Size Components
Authors: Bridges Alex , Griscom Eeva , Gagliano Michael , Siefert John , Penso Jorge , Barrass Jordan 
Published: November 2024

Abstract
Steam methane reforming (SMR) is the most widely used process for bulk hydrogen production and accounts for most of the hydrogen produced worldwide. As this is an highly endothermic reaction, large amount of heat must be supplied to the system, thus requiring heat resistant materials capable of withstanding continued operation at temperatures exceeding 1,500°F (815°C). In this study, microstructural characterization and mechanical testing was conducted on in-service exposed HP40-modified material. Creep damage and changes in precipitate structure were characterized using a variety of microscopy tools. The effect of microstructural evolution on high temperature creep performance due to long-term aging was investigated using standard creep testing methods using round bar specimens. Additional challenges, such as variation in material pedigree, impact of grain structure on performance and importance of test sample orientation are also discussed. The results show that long-term exposure to high temperatures will reduce the overall life of components; however, the resulting ductility increased in samples exposed to the highest temperature. To address challenges with traditional life management procedures, a method for full-scale, high temperature pressurized creep testing of SMR furnace tube samples is being developed and initial results are presented and compared against those from traditional creep specimen geometries.
Acoustic Induced Fatigue of Girth Welds
Authors: Mann J. Adin , Swindell Rob , Hart Noel 
Published: November 2024

Abstract
Assessing the risk of acoustic induced vibration (AIV) fatigue cracks at fittings between pipes, especially at small bore connections, is critical for designing a robust piping system. Girth welds are axisymmetric discontinuities. Examples will be shown of girth weld fatigue that are caused by acoustic induced vibration. These examples are expected to be more common as the asymmetric fittings such as branch connections are designed to be less susceptible to acoustic induced fatigue and then other parts of the piping system become a location for fatigue risk. For example, in some systems with robust asymmetric fittings, the acoustic excitation is allowed to increase assuming that the asymmetric fitting is sufficiently robust. In such a situation, the next location for a fatigue risk can be a girth weld. There are also applications at elevated temperatures where the interaction with creep can reduce the fatigue life. Examples of a girth weld crack in a steam cleanout line, a liner in a Fluid Catalytic Cracker (FCC) overhead line, and in a silencer diffuser will be shown. AIV assessments using the Energy Institute Guidelines for the Avoidance of Vibration Induced Fatigue and other commonly used AIV assessment methods will be shown. An assessment methodology will be proposed for potential use as an industry standard.
Mitigation of Vane Pass Pulsation Induced Vibration in a Crude Oil Pumping Station
Authors: Mann J. Adin , Hart Noel , Tillotson Elizabeth , Sexton Charles 
Published: November 2024

Abstract
The pumps to maintain the flow in long distance crude oil pipelines are typically large, such as 10 kHP pumps. In the example that is shown, the initial piping design and operation resulted in vibration induced fatigue cracks in small bore connections. The frequency of peak vibration was at the vane pass frequency of the pump and was propagated through the piping system as an internal acoustic field. While not the typical acoustic induced vibration of a blowdown system, the impact and mechanisms are the same. Mitigations addressed the problem with seven approaches: (1) modify the design of the pump, (2) modify operating conditions of the pump, (3) apply constrained layer damping to the pipe walls, (4) apply stiffening rings to the pipe, (5) change fitting type on small-bore connections, (6) brace and modify the remaining small-bore connections, and (7) remove all but essential small-bore connections. The impact of the mitigations to the piping system will be presented based on test data for multiple operating conditions. The results show the effectiveness of 4 piping mitigations: stiffening rings, removal of non-necessary small bore piping connections, constrained layer damping, and bracing the remaining small-bore piping with engineered bracing. Recommendations for design approaches are given so that the risk of vibration induced fatigue is minimized through an effective initial piping structure design.
Case Study: Installation and Operation of Non-ASME Stamped Pressure Vessels in the United States
Authors: Barkley Nathan , Chatham Everett , Baquero Kevin 
Published: November 2024

Abstract
The overwhelming majority of pressure vessels installed in the United States are constructed and stamped to the ASME Boiler and Pressure Vessel Code, particularly Section VIII Division 1, as required by most states’ pressure equipment laws. In states where there are laws mandating pressure vessel construction to ASME Section VIII, vessels constructed and stamped to a different construction code or certification body are not allowed unless the state’s laws provide an exception, and the state’s governing body, such as a board, accepts the non-ASME stamped equipment. A vessel that is accepted in this manner typically referred to as a “state special.” Alternatively, a similar exception and approval is needed for previously installed equipment that was not designed to any pressure vessel code, but new operating conditions exceed the state’s applicability limits for pressure, typically 15 psig, or other criteria.
This paper presents two case studies. The first case study examines a case where pressure vessels that were CE stamped in accordance with the European Union’s Pressure Equipment Directive (PED) were requested to be installed in a US state. The next case study examines a case where a vessel was originally built to be non-pressure containing in the 1950s, but recent operational changes raised the possible pressure the vessel could experience higher than the exemptions provided by the state. In both cases, the fundamental considerations and approach for gaining state/jurisdictional acceptance are discussed. Additionally, a review of the US states where pressure vessel laws exist and the states’ specific requirements for pressure vessel installation and operation is provided.
Consideration of Constraint Effect in Fracture Mechanics Assessment for a Vessel Low Alloy Steel
Authors: Louerat Jules , Ancelet Olivier , Marie Stephane , Chapuliot Stephane , Dahl Anna 
Published: November 2024

Abstract
Numerous fracture tests have been performed by EDF and Framatome on various specimen’s geometry extracted from a 18MND5 ferritic steel plate, in the brittle-to-ductile transition regime. C(T), SE(T), SE(B), and non-standard specimens have been tested. This database has been recently updated with SE(T) tests performed in the lower shelf of the transition domain.
This work highlights a robust methodology which allows to predict constraint effect with minor consequences of the choices of the Weibull stress model formulation (classic model, consideration of stress threshold...) and on m parameter on the final interpretation.
A local approach based deterministic industrial method is proposed to consider this effect in Engineering Fracture Mechanics Assessment without considering any probability of failure or statistical approach. It allows to evaluate constraint effect at discrete locations along the crack tip. Its application on industrial cases shows that parameters set have limited impact on constraint effect prediction.