bluuebunny/crossref_metadata_2025_split huggingface dataset:
Safety Assessment of Pressure Vessels in Service for More Than 20 Years
Authors: Xuedong Chen , Zhichao Fan , Jie Dong , Zhibin Ai , Mingdong Hu 
Published: October 2020

Abstract
In recent years, a large number of pressure vessels for the petrochemical plants built in China in the 20th century have been in service for more than 20 years. The Chinese pressure vessel safety specification TSG 21-2016 “Supervision Regulation on Safety Technology for Stationary Pressure Vessel” stipulates that if the pressure vessels without definite design lives have been in service for more than 20 years, they shall be considered to have reached the design service lives. For these pressure vessels, if they are all blindly scrapped, it will cause huge economic losses. However, if they continue to be used blindly, it may bring great safety risks. In this paper, the failure mode, mechanism and damage evolution law are analyzed through a number of failure accident investigations and experimental studies, for typical pressure vessels such as large LPG spherical tanks, pressure swing adsorbers and coke drums. The classification method of pressure vessel for the time-independent and time-dependent failure modes has been proposed. As for the pressure vessels with time-independent failure modes, the principle to determine target life, and the strategy of inspection and maintenance have been proposed. While for the time-dependent failure modes, the safety evaluation and remaining life prediction methods for the pressure vessels with and without defects have been provided. Finally, the advices on amendment to the relevant regulations on pressure vessels have been proposed. The research findings could provide guidance for rationally determining the safety grades and scientifically extending the service lives of pressure vessels.
Volumetric Damage Modeling of High Temperature Hydrogen Attack in Steel Using a Continuum Damage Mechanics Approach
Authors: Bagnoli K. E. , Cater-Cyker Z. A. , Holloman R. L. , Hay C. A. , Chavoshi S. , Nikbin K. M. , Hill L. T. 
Published: October 2020

Abstract
Hydrogen attack is a degradation phenomenon that affects process equipment operated at elevated temperatures in an environment containing a high hydrogen partial pressure. It has been the subject of numerous studies over the years prompted by damage discovered during routine inspections, or incidents that have occurred in service. As non-destructive evaluation (NDE) techniques have improved, damage is being detected during earlier stages where safe operation may still be possible for some time period. This work focuses on the fitness for service evaluation of equipment containing high temperature hydrogen attack (HTHA) using a continuum damage mechanics (CDM) approach. The model can be employed to assess the loss in load bearing capacity due to damage in the form of widespread micro-fissuring and voids (i.e. up to the point of macro-crack coalescence). Experimental data from literature sources have been used to develop a relationship between damage rate and operational loading conditions. The predictions are compared to field experience to illustrate key aspects of this approach.
Fabrication of Grade 91 Materials Experience in Oil and Gas Applications
Authors: Prajapati Bhadresh A. , Penso Jorge A. 
Published: October 2020

Abstract
A modified 9-Cr alloy was developed by Oak Ridge National Laboratory, in early 1980s, to increase high temperature capabilities of ferritic steels for superheater tubing. The material improved high temperature creep properties by controlling alloying elements and microstructure. The material was added to ASME BPVC in 1983 (thru Code Case 1943) as Grade 91. Higher yield and tensile strength, in comparison to other low-Cr alloy steels (like Grade 22), allowed for fabrication of thinner component wall thickness. This in-turn reduced susceptibility to through-wall thermal stresses during transient events. Directionally this also reduced material costs.
Consequently, petrochemical industries have utilized Grade 91 in applications at Heat Recovery Steam Generation units (HRSG), Steam Methane Reformers (SMR), CO2 Boilers and as convection coils in Ethane conversion units.
Grade 91 material has complex microstructure and requires careful control of welding parameters to assure crack free welds that provide adequate creep ductility and retain creep strength at high temperatures. The current guidelines documented in API 582 and Technical Report 938 provide limited insights on success factors for weldability.
Grade 91 material use has been growing in the recent past Petrochemicals Complex and in offshore applications, at once-throw steam generators (OTSG). The aim of this paper is to share experience on welding parameters. Guidance needs be adjusted to specific projects and repair activities.
Failure Mode Effects Analysis for Section III, Division 5 Class A, High Temperature Service of a Printed Circuit Heat Exchanger
Authors: Jentz Ian , McKillop Suzanne , Keating Robert 
Published: October 2020

Abstract
The mission of the U.S. Department of Energy (DOE), Office of Nuclear Energy is to advance nuclear power in order to meet the nation’s energy, environmental, and energy security needs. Advanced high temperature reactor systems will require compact heat exchangers (CHX) for the next generation of nuclear reactor plant designs. A necessary step for achieving this objective is to ensure that the ASME Boiler and Pressure Vessel Code, Section III, Division 5 has rules for the construction of CHXs for nuclear service.
Given their high thermal efficiency and compactness, expanding the use of Alloy 800H diffusion bonded Printed Circuit Heat Exchangers (PCHEs) beyond their current application in Section VIII, Division 1 to the high temperature nuclear applications is of interest. The research being completed under the Department of Energy project is focused on preparing a draft Code Case for consideration by the ASME Code Committees for high temperature nuclear components which must meet the requirements of Section III, Division 5, Subsection HB (Class A), Subpart B.
Acceptance of a Code Case by the ASME Code Committees to use PCHEs in nuclear service requires a broad understanding of PCHE failure mechanisms. At the highest level, the ASME Code requirements prevent failures of structures and pressure boundaries. Historically, the approach is a process of understanding the known failure modes, such as overload failures, plastic collapse, progressive distortion (ratcheting) and fatigue, and then establishing rules for construction to preclude those failure modes in components. For Division 5 applications, attention to differential thermal expansion, creep life, and creep-fatigue must also be considered. Failure from these loadings is manifest within PCHEs both within the internal micro-channel geometry, and at substantially larger solid header and nozzle attachments. To address the adequacy of the PCHE, a Failure Mode Effects Analysis (FMEA) has been performed for standard etched channel PCHEs. This FMEA is linked to the proposed rules in the code case for compact heat exchangers in Section III, Division 5 Class A applications. The PCHE FMEA covers all design failures addressed by Section III.
Design and Analysis of a High Pressure Laboratory Vessel for Testing Well Cement
Authors: Prabhu Milind , Eliseev Ksenia , Vargas Pedro , Krener John , Nadakuditi Venkata , Sarzynski Melanie 
Published: October 2020

Abstract
The Steam Permeameter Cell is a laboratory-scale pressure vessel used to perform high pressure, high temperature testing on well cement slurries. Initial sizing of the concentric, two chamber vessel was based on design by rule concepts in the ASME Boiler and Pressure Vessel Code, Section VIII Division 1. However, based on the complex transient loading expected during the specified testing protocol, additional engineering design and analysis was performed to understand the effects of thermal gradients on the overall strength and fatigue performance of the vessel. The objective of the engineering assessment was to show compliance with design margins in the Code when non-listed materials are utilized in the construction.
Using detailed analytical modeling of transient, thermo-mechanical loading, the assessment demonstrated that the test vessel was safe to operate based on engineering judgement and established best practices in vessel design by analysis. Furthermore, several design modifications were identified to improve functionality and overall performance of the vessel. The Steam Permeameter Cell design had sufficient static capacity to contain the maximum allowable working pressure (MAWP) of 3,500 psig at a design temperature of 700°F, and fatigue capacity to withstand the intended test protocol over the service life.
Performance-Based Assessment of a Guyed Incinerator Stack Using Field Measurements
Authors: Farrow Kenny T. , Karmakar Jaideep , Subramanian Kannan 
Published: October 2020

Abstract
ASME STS-1 provides guidelines for the design, fabrication, and erection of steel stacks, however there are no specific guidelines for the assessment of guyed steel stacks already in service. For example, drift (i.e., displacement) acceptance criteria are only provided for initial installation. Furthermore, existing literature regarding the proper re-tensioning of guy wires is scarce or nonexistent. This procedure is particularly important for stacks that experience significant thermal growth. This effect is further exacerbated by differential wind cooling effects on both the guy wires and on the stack itself. This paper investigates the effect of guy wire spacing, position, tension pattern, and operating and shutdown tension settings on the structural response of a guyed steel stack. Field thermography readings, ultrasonic testing (UT) thickness data, guy wire tension measurements, and laser scans are used to refine a finite element model of the stack. Using elastic-plastic nonlinear “pushover” analyses based on API 579 – 1 Level 3 fitness-for-service methodology and FEMA 356 rehabilitation guidelines, a performance-based methodology resulting in a “watch circle” approach for lateral displacement is provided to guide fitness-for-service assessments and mitigation implementation. Example application of this methodology and recommendations regarding guy wire tensioning are provided for an incinerator stack with 9 guy wires (3 levels – 3 guy wire configuration).
Experimental Study on Excitation of Heat Exchanger Tubes Based on Turbulence Power Spectrum
Authors: Wang Yuqi , Tian Ce , Guo Kai , Zhu Guorui , Tan Wei 
Published: October 2020

Abstract
In the steam generator, anti-vibration bars are often provided to support the tube bundle. Due to the non-linearity of the support, the fluid-solid coupling simulation of large-scale tube bundles supported by the anti-vibration bars will bring great trouble. In order to solve this problem, this paper conducts experiments on the heat exchange tube based on the turbulent power spectrum to generate the excitation force. By changing the support form, the force of the lift and the direction of the drag and the ratio of the force, the excitation of the heat exchanger tube is researched. The results of the displacement response, the contact force and friction force distribution, and the contact angle distribution provide reference for the subsequent model simplification. Experiments show that the contact rate increases with the increase of the excitation force, and the contact force and the friction force increase with the increase of the excitation force. When the heat exchange tube contacts with the anti-vibration bars, the contact angle is mostly less than 45°, more than 50% of the contact angle is less than 45°. The work rate of the tube at the edge is greater than the work rate of the tube in the center.
Rank Predictions of Internal Corrosion of Gathering Pipelines in a Natural Gas Field With a Multi-Kernel SVM Method
Authors: Li Yuejiao , Zeng Weiguo , Li Xiufeng , Ren Fajun , Hu Haijun 
Published: October 2020

Abstract
Internal CO2/H2S corrosion of gathering pipelines is a serious problem in natural gas plant. It is important for field engineers to assess the corrosion degree and control corrosion risk. A multi-kernel support-vector-machine (SVM) method is presented to rank internal corrosion of gathering pipelines according to the NACE RP-0775-91 standard. By considering the nonlinear indivisibility between data, we combined three kinds of kernels (linear kernel, polynomial kernel, and Gaussian kernel) into a multi-kernel SVM to rank the internal CO2/H2S corrosion of gathering pipelines. The method was applied to a natural gas field in northwest China. Corrosion data were collected and analyzed. The prediction accuracy of the multi-kernel SVM method for ranking CO2/H2S corrosion was 66%, which is higher than the results of the single-kernel SVM methods (linear kernel, polynomial kernel and Gaussian kernel), whose prediction accuracies are 50%, 48% and 54% respectively. These findings could help field engineers rank corrosion and reduce the corrosion risk.
Seismic Test Results of the Main Steam Isolation Valve for Japanese Boiling Water Reactor Nuclear Power Plants
Authors: Itabashi Hideaki , Tsutsumi Yoshitaka , Nishino Koji , Kumagai Shin 
Published: October 2020

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 used a resonant shaking table in the Central Research Institute of the Electric Power Industry (CRIEPI), which is capable of seismic tests at acceleration levels previously unachievable, and in seismic tests carried out on an MSIV, we obtained results confirming that validated seismic operability was possible even at response accelerations as high as 15 × 9.8 m/s2.
The seismic operability results obtained for this MSIV will be applied to a fragility analysis of seismic PRA.
Subsea Flanges, Comparison Between Conventional API 6A Type 6BX Flange and SPO Compact Flange Designs
Authors: Lutkiewicz Przemyslaw , Robertson David , Lee Sam (Kwok Lun) 
Published: October 2020

Abstract
The API flange design is a well-known commonly used solution. The flange concept was developed in late 1920s and 1930s by Waters and Taylor. The design methodology of the flange was published in 1937[1], well known as the “Taylor Forge method”. This is still the basis of the present ASME flange calculation. The design is based on the simple elastic principles and linear stress analysis/calculations. The conventional flange type dimensions are described in API 6A [2] and analyzed in API 6AF [3] and 6AF2 [4]. On the other hand, the Compact Flange concept was presented first by Webjørn in 1989 VCF joint [5]. It is based on plastic theory equations and plastic collapse capacity. In 1989 the initial concept was adopted by the Steel Product Offshore (SPO) company for oil industry by equipping flange with HX seal ring for raiser and subsea use. After that a topside budget version (with simpler IX seal ring) was prepared by SPO and presented on PVP 2002 conference [6][7][8]. The Compact Standardized and simplified flange design with IX seal ring is defined and described in ISO-27509 [9]. As for today, along ASME B.16.5 [10] pressure classes range, SPO CF 5K, 10K, 15K and 20K rating flange classes were designed and are in use. The main advantages for CF design are reliability, low weight/compact dimensions and static behavior compared to the conventional design. The design is already well known and commonly uses for European region (mostly Norway). Despite its benefits, CF is still rare outside Europe region. A comparison between those two different concepts will be presented in this paper followed by the examples and Finite Element Analysis (FEA). In case of FEA the Compact Flange design is more suited to the plastic collapse analysis than to elastic stress evaluation as it is for API, therefore comparison between different FEA approaches will be studied in addition.
Strain Control Correction for Fatigue Testing in LWR Environments
Authors: Vankeerberghen Marc , Mclennan Alec , Simonovski Igor , Barrera German , Arrieta Gomez Sergio , Ernestova Miroslava , Platts Norman , Scibetta Marc , Twite Marius 
Published: October 2020

Abstract
During strain-controlled fatigue testing of solid bar specimens in a LWR environment within an autoclave, it is common practice to avoid the use of a gauge length extensometer to remove the risk of preferential corrosion and early crack nucleation from the extensometer contact points. Instead, displacement- or strain-control is applied at the specimen shoulders, where the cross-sectional area of the specimen is higher and so surface stress levels are lower. A correction factor is applied to the control waveform at the shoulder in order to achieve approximately the target waveform within the specimen gauge length.
The correction factor is generally derived from trials conducted in air by cycling samples with extensometers attached to both the shoulders and the gauge length; typically, the average ratio between the strains or the ratio at half-life in these locations is taken to be the correction factor used in testing. These calibration trials may be supplemented by Finite Element Analysis modelling of the specimens, or by other analysis of results from the calibration trials.
Within the INCEFA+ collaborative fatigue research project, a total of six organizations are performing fatigue testing in LWR environments within an autoclave. Of these, one organization is performing tests in an autoclave using extensometers attached to both the specimen shoulders and the specimen gauge length. Therefore the INCEFA+ project provides a unique opportunity to compile and compare methods of shoulder control correction used by different organizations when fatigue testing in LWR environments.
This paper presents the different methods of correcting shoulder control waveforms used by partners within the INCEFA+ project, compares the correction factors used, and assesses sensitivities of the correction factor to parameters such as specimen diameter. In addition, correction factors for air and PWR environments are compared. Conclusions are drawn and recommendations made for future fatigue testing in LWR environments within autoclaves.
An Alternative Corrosion Risk Assessment Method for Industrial Pipelines in Natural Gas Purification Plant
Authors: Wu Wei , Hu Haijun , Lv Yuhai , Zeng Weiguo , Li Xiufeng , Song Ke , Du Xinshuang 
Published: October 2020

Abstract
Natural gas is a kind of high-quality and low-carbon energy and its demand is increasing rapidly year by year. The natural gas produced from the gas well contains some corrosive impurities like CO2, H2S, and H2O. Therefore, the gas needs to be purified in purification plants before it can be used. In the process of purification, the impurities in the natural gas will cause corrosion to the purification equipment, especially to the industrial pipeline, which will lead to perforation and leakage of the pipeline, and even cause poisoning, fire or explosion, and other serious safety accidents. In order to ensure the safe operation of the industrial pipeline in the purification plant, it is necessary to carry out effective inspection and maintenance measures for the pipelines.
The traditional regular inspection method just inspects a certain proportion of the pipelines which are selected by on-site inspection personnel. But limited by technical level and work experience of the inspection personnel, some high-risk pipelines may be neglected. Therefore, some plants try to adopt risk-based inspection (RBI) to carry out a risk assessment and conduct a comprehensive inspection on high-risk pipelines, so as to improve inspection efficiency and reduce inspection cost. However, in practice, it was found that the pipeline risk levels are not in accordance with the actual inspection results. The reason is that the RBI method developed in the background of oil refining and chemical industry is not suitable for natural gas purification plants.
In order to solve the problems, this paper analyzed the relationship between the influencing factors and pipeline corrosion behavior. The influencing factors include the impurity contents (CO2, H2S, H2O, and chlorides), pipeline materials (carbon steel and austenitic stainless steel), and service conditions (operating temperature, operating pressure and flow velocity). Meanwhile, the plant management status and maintenance factors were also considered as the influencing factors to pipelines. According to the analysis, a corrosion risk assessment method for the pipelines in the natural gas purification plant was developed based on fault tree and scoring method. Finally, the method was applied to the pipelines in purification plant to verify the accuracy of this method.
Thermal Fatigue Cracking due to Intermittently Flowing Drain Water in Steam Piping
Authors: Koki Saito , Tomohiro Watanabe 
Published: October 2020

Abstract
In a petrochemical plant, a steam leak incident happened due to a through-wall crack, which was found around the branch connection between the superheated steam pipe header and the branch pipe for the safety valve. Similar cracks had been observed in the Normally No Flow (NNF) line pipes sometimes. We decided to investigate the cause of these cracks. The crack was found along the circumferential welding line of the branch connection. According to the microfractography, the origin of the crack was internal surface of the pipe and it propagated through the thickness of the wall. Striations were observed on the fracture surface, and it showed the fatigue effect. All the NNF line pipes where the leak incidents occurred were installed upward and then connected to the horizontal pipe toward the safety valve. Infrared thermographic testing revealed that the steam drain pooled in the horizontal pipes was flowing intermittently toward the superheated steam pipe header. Cyclic thermal stress was sure to occur in the damaged area with calculation by FEM, and the cause was assumed to be thermal fatigue cracking due to intermittent dripping of drain water condensed in the NNF pipe. We decided to correct the slope of the horizontal pipe so that the drain was not pooled. Also, we checked all other NNF line pipes upwards and confirmed that there was no possibility of a similar incident due to drain in the horizontal pipe.