bluuebunny/crossref_metadata_2025_split huggingface dataset:
Seismic Test Results of the Main Steam Isolation Valve for Japanese Boiling Water Reactor Nuclear Power Plants (Part 2)
Authors: Itabashi Hideaki , Tsutsumi Yoshitaka , Nishino Koji , Kumagai Shin , Kubota Ryo , Tanemura Shota 
Published: November 2022

Abstract
The functional requirements of Main Steam Isolation Valves (MSIVs) provided in the Boiling Water Reactor (BWR) nuclear power plants in Japan have been previously evaluated via seismic tests and so forth. However, since the response acceleration has increased in line with a recent reassessment of standard earthquake ground motions, it is necessary to evaluate seismic operability with respect to high acceleration. In addition, from the viewpoint of equipment fragility in seismic PRA, it is necessary to determine practical seismic operability limits.
We already confirmed that MSIV has capable of maintaining correct function for response accelerations up to 15 × 9.8 m/s2 in all directions (see Ref.[1]) using a resonant shaking table in the Central Research Institute of the Electric Power Industry (CRIEPI) (see Ref.[2]), which is capable of seismic tests at acceleration levels previously unachievable.
Additional seismic tests for a MSIV were conducted and we obtained results confirming that validated seismic operability was possible even at response accelerations as high as 20 × 9.8 m/s2.
The seismic operability results obtained for this MSIV will be applied to a fragility analysis of seismic PRA.
An Investigation About the Ageing Behaviour of Pre-Applied Threadlockers
Authors: De Agostinis Massimiliano , Croccolo Dario , Fini Stefano , Olmi Giorgio , Robusto Francesco , Scapecchi Chiara 
Published: November 2022

Abstract
Pre-applied threadlockers are widely adopted in industrial applications, due to their favorable features in terms of handling of the fastener and savings in terms of assembly-line dosing systems. In the practice, fasteners with the pre-applied adhesive may undergo storage and/or shipping in harsh environmental conditions, both in terms of temperature and humidity. Questions may arise as to whether such thermal-hygroscopic aging (prior to assembly): (i) affects the tribological properties of the fastener at tightening and/or (ii) the breakaway torque of the fastener after curing. By means of an experimental approach, this work primarily aims at answering the first question, indeed scarcely covered by the literature. As for the second question, measurement of the breakaway torque is carried out for the sake of comparison with the data provided by the adhesives datasheets, where available. Based on a common bolt and plate configuration, the study involves different pre-applied threadlockers in terms of strength grade, among several hygrothermal conditions, representative of frequent storage/shipping conditions. The experimental data have been analyzed by means of the ANOVA tools to assess the effectiveness of the input parameters (adhesive type and aging conditions) on the response in terms of both thread friction coefficient at tightening and breakaway torque of the fastener after tightening completion and complete polymerization. Guidelines useful to the design engineer are reported in the conclusions.
Statistical Analyses of Austenitic Stainless Steel High Cycle Fatigue Data to Support a Revised Design Factor for Design Fatigue Curve Development
Authors: Morley Andrew , McLennan Alec 
Published: November 2022

Abstract
In the 2009 addendum to the ASME BPV Code [1], new design fatigue curves were adopted for austenitic stainless steel and nickel-based alloys. These changes followed publication of NUREG/CR-6909 [3] which, in addition to describing a methodology to account for environmental effects on fatigue, challenged both the mean air curve underlying the design fatigue curve and factors used to define the design position from this mean behaviour.
The methodology to build the design curve starts with the mean air curve obtained by laboratory testing, a correction is made for mean stress effects and then the resulting curve is translated by coefficients, referred to within this paper as design factors, applied on stress or on cycles, with the lower of the two translated curves defining the design curve. The translation by these design factors is to account for factors present in service applications but not present in the laboratory testing and also to provide a conservative position accounting for scatter in fatigue behaviour.
Following a detailed review of the appropriate factor on cycles in NUREG/CR-6909 [3], the revised ASME design curve replaced the historic design factor of 20 on cycles with a factor of 12, although a later revision of NUREG/CR-6909 [4] further refined this to below 10, the factor of 12 remains. The historic design factor of 2 on stress was not reviewed in any detail NUREG/CR-6909 and was not changed at this time. However, a number of reviews previously and since [5],[6] and [7] have suggested that a design factor of 2 is excessive compared to the aim of describing a 95% bounding curve position.
This paper presents a series of statistical analyses of the same austenitic stainless steel data used to generate the mean curve fit underlying the current design curve, supplemented with additional, high-quality, modern data to demonstrate that a substantially-reduced factor on stress would be appropriate to the aims of describing a 95% bounding curve.
In conjunction with other recent literature, these analyses present a strong basis for revision of this historic excess-conservatism while maintaining a suitably-conservative position. However, as such blanket conservatisms are reduced, the limitations, simplifications and assumptions of the current curve form and design curve construction must be discussed and evaluated, this wider context is described to support further discussion.
Complex Lattice Structure-Based Heat Exchangers Through Additive Manufacturing: Opportunities and Challenges
Authors: Wong Jerome , Qureshi Ahmed , Mertiny Pierre 
Published: November 2022

Abstract
Cellular structures are a class of materials that offer greater stiffness, strength-to-weight ratio, good energy absorption capacity, and high heat transfer capability compared to solid parts. Metallic lattice structures have been applied in different industry sectors, such as in biomedical implants, lightweight components, energy absorbers, and catalytic reactors. With the development of advanced manufacturing techniques, especially additive manufacturing (AM), lattice structures with complicated designs can be produced. Lattice structure-based heat exchangers produced by AM techniques have recently gained significant attention due to their promising performance. Interconnected cavities in lattice structures provide flow of fluid and effective thermal conductivity, which is desirable in heat exchangers. AM methods provide the possibility to promote tortuosity and intricate flow patterns leading to improved performance of heat exchangers. Between different AM techniques, laser powder bed fusion (LPBF) proved to be a suitable method for the manufacture of heat exchangers. Using LPBF methods, the distribution and geometry of cavities in the structure can be controlled with an accuracy that is typically better than for other AM methods. Although LPBF-produced heat exchanger showed enhanced thermal conductance, there are limitations associated with LPBF fabrication, such as surface roughness and need for post processing. In order to bridge this gap, the effects of different process parameters and levels of structural complexity in LPBF processes need to be evaluated. In this context, the present contribution constitutes a position paper that contrasts the opportunities that LPBF may provide for the fabrication of heat exchangers with the challenges that need to be overcome to realize design solutions that meet industry demands.
Seismic Vulnerability Assessment and Fragility Functions Derivation for Steel Storage Legged Tanks
Authors: Gabbianelli Giammaria , Perrone Daniele , Nascimbene Roberto , Paolacci Fabrizio 
Published: November 2022

Abstract
The major earthquakes that occurred worldwide in the last decades highlighted the seismic vulnerability of industrial structures and their components. Beyond the need to avoid human losses, the damages experienced by industrial facilities, both in terms of structural, non-structural and plant elements, significantly affected the economy of such areas. On the one hand, often the damages of non-structural components and their contents immediately lead to significant monetary loss. On the other hand, the leakage of toxic contents or the disruption of mechanical equipment can conduct to down-time of industrial plants. Following the 2012 Emilia earthquake in Italy, one of the most damaged components in industrial facilities, among others, was the steel storage legged tank.
This research aims to investigate the seismic vulnerability of such elements by defining suitable fragility functions, also useful for future loss estimation studies. Several engineering demand parameters (EDPs) were selected in order to line up the damages observed in the aftermath of earthquakes. To draw general conclusions, several legged tanks were selected and analyzed. A suitable record selection has been performed, for which the average spectral acceleration (AvgSa) was selected as intensity measure (IM). Once adequate performance objectives were defined, the legged tank archetypes were analyzed by means of multiple-stripe analyses (MSA) to calculate the fragility functions and to highlight the most critical elements and tank configurations.
Use of HDPE Piping in Buried Nuclear Class 3 Systems Categorized as Low Safety Significant
Authors: O’Sullivan J. E. (Jim) 
Published: November 2022

Abstract
Code Case N-755 and ASME Section III Appendix XXVI were developed by ASME for providing deterministic rules for new construction of Class 3 buried piping using High Density Polyethylene (HDPE) piping. These rules contain many special treatment requirements consistent with deterministic rule making, that have essentially put HDPE out of economic contention with other choices for replacement of degraded buried Class 3 piping such as using thicker-walled carbon steel piping, low alloy piping material, or even AL6XN. Re-evaluation of buried portions of Class 3 safety-related service water and cooling water piping using the risk-informed provisions of 10 CFR 50.69 or Code Case N-752 should result in recategorization of most buried Class 3 service water piping as Low Safety Significant, enabling relaxation of many of those special treatment requirements.
This paper describes an approach that will apply ASME Section III Appendix XXVI for replacement of Class 3 buried piping categorized as Low Safety Significant while exempting the design and construction from several special treatment requirements of Section III Appendix XXVI. This approach provides alternative treatment provisions for material procurement, design, fabrication, installation, and testing of technically superior HDPE piping as a cost-competitive permanent replacement for degraded buried safety related Class 3 carbon steel piping.
Study on the Bonding Strength and Corrosion Resistance of Low-Pressure Cold Sprayed Al/Al2O3 Composite Coatings on Pressure Vessel Steel Substrate
Authors: Wang Yonggang , Liu Xin , Sun Liang 
Published: November 2022

Abstract
Due to the complex working environment, the defects were easily produced on the surface of pressure vessel plate, such as scratch, wear and corrosion pit, which reduced the service life of equipment. As a new surface coating preparation technology, cold spraying technology can be used to effectively repair and protect the substrate. With the development of cold spraying technology, more and more metal powders are used to prepare functional coatings, but aluminum powders are used most frequently due to significant plasticity and corrosion resistance. However, pure aluminum coating have a obvious shortcoming with lower bonding strength, and most of bonding strength values of coatings and steels are about 14.6 MPa. With the aim to improve the mechanical properties more of pure Al, the most representative one is the inclusion of ceramic particles as reinforcement to produce dense coatings. Thus, the Al-Al2O3 composite coatings of the different Al2O3 weight fractions were deposited on the surface of pressure vessel plate by cold spraying technology. The strength and corrosion resistance of the coatings were evaluated by tensile test, corrosion weight loss measurement and electrochemical test. The results show that the bonding strength of pure Al coating is the lowest among the four cold spray coatings, and the bonding strength sharply increases while the coating increased Al2O3 particles, and the largest values with bonding strength of Al-Al2O3 is as high as 45.4 MPa. The tensile test was carried out under the allowable stress of pressure vessel. Observations under optical microscope (OM) were also done, and the coating has excellent quality and no new cracks and holes. The corrosion weight-loss of the substrate and composite coatings were measured, and the corrosion weight loss rate of Al-Al2O3 was 5 times lower than that of pressure vessel plate. In addition, for all the coatings, the values of weight loss had little changes. It is observed that the values of the composite coating was exhibited a peak with an increasing of the Al2O3 content. The Al-20wt.%Al2O3 was shown the best corrosion resistance and the value of weight loss was 0.11(g/cm2*h), which probably was attributed to the effect of the lower porosity. Potentiodynamic polarization curves were shown the corrosion current density of composite coatings were one order of magnitude lower than that of the substrate. Therefore, we concluded that the corrosion resistance is obviously better than that of the substrate, which can effectively protect the substrate and delay the service life of the pressure vessel plate.
Study on Skirt Base Ring Reinforcement for Tailing of Vertical Vessels
Authors: Mihara Yuki , Kataoka Shunji , Okami Atsushi , Takahashi Kyohei 
Published: November 2022

Abstract
EPC contractors / manufacturers design and use the lugs attached on the skirt for tailing of vertical vessels. To avoid the overstressing and deformation of the skirt base ring due to tailing load, the reinforcing beams attached inside the base ring may be considered. Since the design rules for tailing devices are not described in ASME BPVC Section VIII, the soundness of the tailing design could be left to the judgement of individual parties. In past projects, the deformation of the skirt base ring during lifting work at construction site occurred and gave huge impact on construction schedule and cost.
As per the theoretical calculation for the design of the skirt base ring reinforcements, the beams are generally considered as “rigid” structure. Based on the results in this paper, it can be said that the base ring may be overstressed and largely deformed if the axial stiffness of the reinforcing beams is not properly taken into the consideration of tailing design, especially for large diameter vessels.
This paper provides the basic concept and practical design consideration of the skirt base ring subject to tailing load by investigating the tendency of bending moment and residual plastic deformation of the skirt base ring with several types of reinforcing beam arrangement.
Stress Evaluation of a Three-Point Supported Heat Exchanger
Authors: Raman Senthil Kumar 
Published: November 2022

Abstract
This paper focuses on developing formula-based method to predict shell stresses in a high-pressure heat exchanger with three-point supports. It compares the results with Finite Element Analysis (FEA) based design procedure. High pressure heat exchanger is supported with two saddles on shell (fixed and sliding saddles) and one lug support on channel due to heavy thk. tubesheet and channel flanges. Heat exchanger vessel part is considered as a hollow circular beam and closed form solutions are derived using continuous beam theory. Three-dimensional (3D) Finite Element model is developed using Ansys® and three types of meshing options are considered i.e., tetrahedron mesh, hex dominant mesh, and shell element mesh. Linear static structural analysis is performed, and shell membrane plus bending stresses are extracted by linearizing the axial stresses along the Stress Classification Lines at four shell locations using PVRC 3D stress criteria (Bulletin WRC 429). Longitudinal membrane plus bending stresses are calculated for the severe most design load case: Internal pressure, superimposed tubesheet weight and ship motion acceleration loads. Stress values which are obtained by formula-based approach and FEA are compared at four shell locations and conclusions are drawn.
Multiphase Flow Induced Forces for Horizontal and Vertical Systems
Authors: Pereboom Hajo , Belfroid Stefan 
Published: November 2022

Abstract
Multiphase flow is a known source of vibrations in piping systems. Multiple experimental campaigns have focused on the force spectrum on horizontal bend systems. To evaluate the evolution of multiphase forces through a vertical loop, experiments have been done on an air-water, two inch pipe system consisting of four bends at near-atmospheric conditions. Forces are measured at each bend by clamping the pipe and measuring the strain. The experiments consist of two phases with the same loop in both a vertical and horizontal orientation. The change in orientation reveals the difference between a vertical and horizontal force development for the same u-shape geometry. The results show a difference in force development through the bends in a vertical system compared to the horizontal orientation. The force on the lower bend in an upwards orientated pipe plateaus on a minimum value for low gas velocities. The other bends in the system do not show this behavior. The effect of a vertical section on the coherence between the bends is investigated and compared with the horizontal orientation. Due to the larger difference in flow pattern in the vertical parts of the loop the coherence between the bends is lower when compared with the horizontal layout.
Numerical Method to Determine Fracture Toughness Under Hydrogen Environment From Small Punch Test Data and Experimental Validation
Authors: Seo Ki-Wan , Hwang Jin-Ha , Kim Yun-Jae 
Published: November 2022

Abstract
This paper proposes a simple method to predict the fracture toughness of hydrogen-embrittled material using a hydrogen-embrittlement constant. The effect of hydrogen-embrittlement on fracture strain can be quantified via hydrogen-embrittlement constant, and it can be obtained by simulating small punch test in hydrogen. The fracture toughness of hydrogen-embrittled material can be simply estimated by multiplying the constant on fracture toughness of the un-embrittled material. The result of estimation shows good agreement with the published experimental data.
Creep Fatigue Damage Assessment of the Welded Structures of High-Temperature Pressure Equipment Based on DIC Technology
Authors: Fan Zhichao , Zhou Yu , Chen Xuedong 
Published: November 2022

Abstract
In recent years, pressure equipment tends to operate under higher temperature and higher pressure with the rapid development of world economy, resulting in greater significance of creep fatigue damage that is strongly temperature and time dependent. This brings new challenges to the design, manufacturing, operation and maintenance management of the high-temperature pressure equipment. The welded structure of high-temperature pressure equipment exhibits heterogenous microstructures with mismatched mechanical properties, as well as the unavoidable weld defects. Damage characterization, life design and failure assessment of welded structures have always been challenging difficulties. Hence, the welded structure is the weakest link for creep fatigue failure. The present paper introduces the research progress on creep fatigue damage assessment method for the welded structures of high-temperature pressure equipment in China, based on the digital image correlation (DIC) technology and the ductility exhaustion theory. It involves in-situ characterization of heterogenous creep deformation of welded joints by using the digital image correlation technology, creep damage assessment of welded structures by finite element modeling, evaluation of strain enhancement effect and life-based creep fatigue strength design of high-temperature welded structures, etc. This method can provide useful guidance for establishing the prevention and control schemes for creep fatigue damage of high-temperature welded structures.
Load Loss as a Factor Impacting Gasket Leakage
Authors: Rice Dale A. , Waterland Jerry 
Published: November 2022

Abstract
After flange assembly and following a period of operation, some of the compressive stress on a gasket is lost due to factors such as temperature, pressure, flange movement, and material composition. Increased leakage (fugitive emissions) is often a result of gasket stress loss; however, the increased, operating leak rate is not necessarily directly proportional to the degree of gasket stress loss. A study was conducted using a previously published leak rate model based on an equation set derived from the Pressure Vessel Research Council to provide a demonstration of the impact of load loss (under operating conditions) on the predicted gasket leak rate. The model incorporates system pressure and gasket stress as input variables along with gasket specific factors determined from room temperature tightness test data. Model-derived leak rate data have been plotted as a function of gasket assembly stress for several material types including polytetrafluoroethylene, compressed fiber, and flexible graphite. Plot trends were found to vary noticeably by material type as well as by manufacturer. The derived model outputs are a confirmation that predicted leak rates are not linearly proportional to the degree of gasket stress loss. The results of this study may be instructive to the end user for comparing predicted leak rates of gasket materials over a gasket stress loss range associated with a given application.
Fracture and Tensile Characterization of Additively Manufactured Type 300 Series Stainless Steel in the Baseline and Hydrogen Charged Conditions
Authors: Krentz Tim , Korinko Paul , McWilliams Anthony 
Published: November 2022

Abstract
Savannah River National Laboratory (SRNL) has characterized powder bed fusion processed Type 304L stainless steel for use as hydrogen storage and process vessels. As part of this characterization, a simple cylinder (C-cylinder) and a “D-cylinder” were fabricated using two different Laser Powder Bed Fusion (L-PBF) machines at two different sites. These four sample cylinders were electrical discharge machined (EDM) into cylindrical blanks and rectangular blanks and subsequently finished machined into tensile samples and single edge notched three-point bend fracture toughness samples, respectively. The microstructures of the cylinders were optically characterized parallel to the build direction and perpendicular to the build direction at three elevations. Samples were hydrogen charged using conditions to generate approximately 70 wppm (3700 appm) hydrogen. The sub-sized cylindrical tensile samples and fracture toughness samples were non-destructively characterized using computed tomography with a voxel size of nominally 80 microns. Metallographic analysis and CT indicated the samples are virtually pore free and exhibit the expected microstructure of L-PBF processing. The mechanical test samples were tested in the baseline and hydrogen charged conditions to determine the tensile and fracture toughness behavior; based on previous results, the baseline tensile and fracture properties are comparable to wrought material and the hydrogen properties exhibit similar characteristics to wrought materials.