bluuebunny/crossref_metadata_2025_split huggingface dataset:
Microstructure and Oxidation Behavior of Narrow Gap Brazing and Wide Gap Brazing Joints With Boron/Silicon-Free Nickel Base Braze Alloys
Authors: Huang Xiao 
Published: October 2020

Abstract
In this study, the microstructure and solidus and liquidus of several Ni-Co-Hf-Zr-Ti-Al braze alloys were first examined with the objective to develop a B- and Si-free low-melting braze alloy for narrow gap (NGB) and wide gap brazing (WGB) and turbine component repair applications. Among various alloys examined, differential scanning calorimetry (DSC) was used to measure the solidus and liquidus during heating and cooling cycles. Following the measurements of liquidus and solidus, the microstructure was evaluated using SEM. Equations for calculating solidus and liquidus based on alloy's compositions were established, and the functions of each elements on these two characteristic temperatures were discussed. One selected alloy with a liquidus of 1201 °C was further employed for NGB and WGB experiments. The results showed that it was able join Cannon Muskegon single crystal (CMSX)-4 at 1240 °C without interfacial voids, and with the use of externally applied pressure and extended homogenization treatment, the interfacial intermetallic compounds were substantially removed. Furthermore, the same braze alloy was used to fill a large artificial cavity in a WGB scheme at a reduced temperature of 1200 °C. The braze alloy was able to fully bond the filler powder alloy in addition to join the two alloys to an IN 738 substrate. Finally, oxidation test was conducted at 1050 °C (isothermal in static air) for 100 h after NGB of CMSX-4 and WGB of IN 738. The results showed that the oxide formed on the standalone braze alloy is very dense and there is no sign of spallation. It contained primarily NiO (+CoO) with no other elements measured. For the NGB joints, large amount of scale spallation was observed on base alloy CMSX-4 while the NGB joint remained spallation free. The oxide formed on the NGB was NiO with partitions of Co, Al, Ti, Cr, and W. The WGB joint region in IN 738 showed oxide scale spallation on the IN 738 substrate side, leaving behind steps and depression on the sample surface. In the WGB joint itself, there were three notable phases after oxidation test; however, no scale spallation could be found. For the majority part of the surface, a Ni-rich oxide covered the surface. There were areas of smaller oxide particles with higher Cr content. Overall, the new boron/silicon-free braze alloy was found to be able to join several superalloys in both WGB and NGB schemes without occurrence of defects and the oxidation resistance was superior to both substrate alloys examined in this study.
Erosion Prediction of Sub-Sea Xmas Tree Based on CFD
Authors: Rong Xin , Zhu Hongwu 
Published: October 2020

Abstract
Sub-sea vertical Xmas tree is one of the key equipment in the oil industry. Erosion caused by particles in the flow of oil and gas may lead to equipment failure or even interruption of oil exploitation. Therefore, it is important to figure out the characteristics of erosion in vertical Xmas tree. In the present work, the AISI 8630 erosion model and the Forder wall rebound model has been applied to study the erosion of production channel and choke valve in the tree. The maximum and average surface erosion amount are introduced to evaluate the erosion degree. The results show that for the production channel, erosion mainly occurs in the interior of the turning point of the channel and the interior of the downstream wall near the joint, and the most serious eroded area is located at the bottom of the downstream wall of the channel. Comparing the effects of blind pipe length, particle concentration, particle size and flow velocity on the erosion wear of the production channel, it is found that the flow velocity is the main factor affecting erosion. As the velocity of fluid increases, the maximum and the average surface erosion on the inner wall of production channel increase in a steep manner. For the choke valve, as the relative opening increases, the maximum erosion amount decreases sharply. However, compared with the production channel, the wear of the valve channel is much more serious, and more attention should be paid in industrial operations.
Pump Specific Speed and Four Quadrant Data in Waterhammer Simulation: Taking Another Look
Authors: Walters Trey , Dahl Trygve , Rogers David C. 
Published: October 2020

Abstract
In some situations, it is possible for flow to go backwards through a pump during a transient waterhammer event. Sustained reverse flow will lead to reverse rotation. Understanding and predicting the pump behavior during waterhammer under these conditions is typically accomplished using previously published four quadrant pump data. Historically, the selection of which data to use is based on the similarity of pump specific speed. The weaknesses of using specific speed are described and an improved method of selecting appropriate four quadrant data is given based on fundamental curve shapes for head and power in the normal operating zone.
Modeling and Control of Real Flow Calibration System
Authors: Wen Kai 
Published: October 2020

Abstract
The calibration of large-diameter flow meters is performed in the calibration station where real flow passes through. The typical calibration process is manipulated by human operators, which is time-consuming and easily affected. Since most of the process parameters are detectable, the smart calibration system was aided by the on-line modeling process and consisted of three parts: the digital twin model, the process controller, and the human-machine interface (HMI). The digital twin model was based on the basic partial differential equations of the gas flow in pipelines and was meant for the flow behavior prediction over short periods and provided decision-making assistance for human operators. The verification of the digital model was based on both the historical process data and the real-time process data. The process controller represented the manipulator meant to replace the human operator. The function of the controller included process control and calibration flow point adjustment. The HMI was designed based on the industrial supervisory control and data acquisition (SCADA) system. Since the process control was essential, the scheduling scheme and command sequence feedback to the SCADA system was rechecked by human operators via the HMI. The result of the active control was displayed in the HMI based on the digital twin model.
Since smart control was the tendency in the piping system, the automated process verification and control formed the basis of the smart system. By entering the size and range of the flow meters into the HMI, the entire industrial system inside the calibration station was executed automatically.
Research on the Measurement Accuracy of Ultrasonic Phased Array Time-of-Flight Method
Authors: Liu Shu H. , Ding Ju , Wang Jie L. 
Published: October 2020

Abstract
In special public pipelines, High Density Polyethylene (HDPE) had been widely applied, making integrity and safety priority. In the periodic inspection of pressure vessel and pressure pipeline, the safety level shall be determined by the defect geometric size. Therefore, it is necessary to get the defect size data as accurately as possible.
Digital radiography inspection is a feasible method for detecting butt fusion welds. Defect size can be measured accurately by digital radiographic image. Due to factors such as damage to human body caused by ray, it is difficult to detect HDPE pipelines in some occasions in field. Ultrasonic phased array testing has high accuracy in flaw inspection, high efficiency and little artificial criteria error. But conventional phased array has difficulties in detecting butt fusion welds due to acoustic attenuation and noise affection.
In this paper, PE butt fusion welding is inspected by immersion phased array. The absolute time-of-flight method is used to measure the defect size, and the accuracy is qualified with the requirements of the butt fusion welding inspection. For more important, inspector does not need to move equipment probe, avoiding artificial errors and improving the efficiency.
Proposal of Use of Mises Criteria for Elastic Analysis in Appendix 9 of ASME Section VIII Division 3
Authors: Terada Susumu 
Published: October 2020

Abstract
The stress evaluation by elastic analyses for protection against plastic collapse in Appendix 9 is based on maximum shear stress theory (Tresca theory). On the other hand, the stress evaluation by elastic-plastic analysis and design equations by flow stress for design pressure for cylindrical shell and spherical shell in KD-221 is based on distortion energy yield stress theory (von Mises theory). With regard to materials with low and intermediate Sy/Su, in particular the primary stress evaluation based on Tresca stress for elastic analysis in current Div.3 is much more conservative than that based on flow stress equations similar to elastic-plastic analysis from experimental results. In Section VIII Div.2, von Mises yield criterion is used for stress evaluation for elastic analysis because it matches experimental results more closely than Tresca yielding criterion and is also consistent with plasticity algorithms used in elastic-plastic analysis. Therefore in Div.3 von Mises stress should be used for elastic analysis in the same way as in Sec. VIII Div.2. For materials with high Sy/Su, the primary stress evaluation based on von Mises criterion for elastic analysis is less conservative than that based on flow stress equations similar to elastic-plastic analysis because of a difference in design factor of 1.5 for elastic analysis and 1.732 for flow stress equations. Therefore, we propose using von Mises criterion for protection against plastic collapse with design correction factor using Sy/Su in Appendix 9 in order to remove excessive conservativeness for materials with low and intermediate Sy/Su. The validity of this proposal is shown in this paper.
The Research on the Stress Analysis of Overhead Steam Pipeline
Authors: Pu Zhe , Wang Jielu , Ren Bin , Song Pan , Zhao Fan 
Published: October 2020

Abstract
Industrial production is accompanied by a large number of physical and chemical reactions. Steam, whose heat was often used to carry out various production activities, is a common medium in industrial production. Steam pipeline has the characteristics of high temperature and high pressure. The pipeline has been in service at high temperature for a long time, which is prone to metal material degradation such as graphitization and spheroidization. Cause of the expansion of steam pipeline after heating, the natural compensation structure is generally adopted in the whole plant pipe gallery. In recent years, the accidents of steam pipeline occurred frequently, so we must pay more attention to the safety of steam pipeline. Periodic Inspection Regulation for Industrial Pressure Piping (TSG D7005-2018) explicitly requires stress analysis and checking in some cases to determine the safety of the pipeline. The traditional inspection method adopts a random sampling model which has the risk of over inspection and missing inspection. Taking a whole plant steam pipeline as an example, this paper introduced the stress check criterion of pipeline in ASMEB31.3.The model of the pipeline was established by the software, and the stress state and displacement of each node of the pipeline were calculated. According to the calculation results, a targeted inspection scheme was established and effective data support was provided for the regular inspection of steam pipeline.
Comparative Study on Seismic Response Analysis Methods of Spherical Tanks
Authors: Ma Zhongming , Xiao Guang , Zhang Minghui , Zhang Haijun , Du Ruixue 
Published: October 2020

Abstract
Spherical tank is an important storage equipment in petrochemical industry. It is often used to store inflammable and explosive materials. Once it is damaged in the earthquake, it will lead to serious consequences. In this paper, the finite element model of spherical tank is established by ANSYS software. The bottom shear method, mode decomposition method and time history analysis method are used to calculate the strength of spherical tank. The weakest link of the structure under the real earthquake load is determined, which provides the basis for the seismic safety guarantee and structural design of spherical tank. The applicability of the three calculation methods is compared and discussed.
Multiphase Flow Induced Vibrations at High Pressure
Authors: Belfroid S. P. C. , Gonzalez-Diez N. , Lunde K. , Orre S. 
Published: October 2020

Abstract
High pressure experiments were done to determine the pressure effect on multiphase induced forces. To that end, a series of water/gas, oil/gas and oil/water/gas vibrations measurements were performed at 10, 25, 45 and 80 bar at different liquid and gas rates in a horizontal, 2″, double Uloop test section installed at the Equinor Porsgrunn site. At higher pressures the vibration amplitude decreased inversely proportional to the pressure. This was measured for both oil and water. Based on the vibration data, the forcing spectrum was reconstructed. In this the same decreased trend was observed, indicating that a changed damping is not the cause of the reduced vibrations. In the forcing spectra the main effect was a higher energy content at lower frequencies. No clear shift in the peak frequency was measured.
Fracture Mechanics Assessment of Reactor Pressure Vessel Irradiated Structural Steel for Short Column Type Supports and Neutron Shield Tank
Authors: Carolan Alexandria M. , Hall J. Brian , Longwell Stephen K. , Alpan F. Arzu , Imbrogno Gregory M. , Udyawar Anees A. , Boggs Scott , Franzone Steve , Tomes Charles , Haluska Beth 
Published: October 2020

Abstract
As plants apply for 80 year licensure (subsequent license renewal), the United States Nuclear Regulatory Commission (U.S. NRC) has queried the nuclear power plant industry to investigate the impact of neutron embrittlement (radiation effects) on the reactor pressure vessel (RPV) structural steel supports due to extended plant operation past 60 years. The radiation effects on RPV supports were previously investigated and resolved as part of Generic Safety Issue No. 15 (GSI-15) in NUREG-0933 Revision 3 [1], NUREG-1509 [2] (published in May 1996), and NUREG/CR-5320 [3] (published in January 1989) for design life (40 years) and for first license renewal (20 additional years). The conclusions in NUREG-0933, Revision 3 stated that there were no structural integrity concerns for the RPV support structural steels; even if all the supports were totally removed (i.e. broken), the piping has acceptable margin to carry the load of the vessel. Nevertheless, for plants applying for 80 year life licensure, the U.S. NRC has requested an evaluation to show structural integrity of the RPV supports by accounting for radiation embrittlement (radiation damage) for continued operation into the second license renewal period (i.e. 80 years).
The RPV support designs in light water reactors are grouped into one of five categories or types of supports: (1) skirt; (2) long-column; (3) shield-tank; (4) short column; and (5) suspension. In this paper, two of these RPV support configurations (short column supports and neutron shield tank) will be investigated using fracture mechanics to evaluate the effect of radiation embrittlement of the structural steel supports for long term operations (i.e. 80 years). The technical evaluation of other support configurations will be provided in a separate technical publication at a future date.
Piping and Equipment Dynamics of High Rate HVGO Pumps
Authors: Kaye Alwyn 
Published: October 2020

Abstract
A set of Heavy Vacuum Gas Oil (HVGO) pumps in a 300 kbbl/day operating Upgrader Plant experienced repeated failures; typically less than 7 weeks. The pumps run continuously in a high-pressure, high temperature and corrosive environment and their functional status directly affects the reliability of the plant. Upon research, an experimental strain measurement technique using very high resolution laser digital imagery and optical metrology was found from military and advanced aerospace applications to verify high level dimensional accuracy of critical components [1]. Application to a complex and operating bitumen upgrader was unknown.
The objective of this project was to use advanced optical metrology with digital image processing techniques employing multiple laser and high-speed cameras capable of generating pump and pipe component’s real time strain images, displacement and rate of change. Optical metrology can analyze the mechanical properties and behavior of many materials and in various test scenarios [2]. Hot and cold operating service, with variations in flow and temperature all dynamically affect the strain measurements. Three significant advantages of the optical method are:
i. Avoids a host of problems of strain gauge application, wiring and setup.
ii. The problems of temperature sensitivity and correction are overcome. [3]
iii. Gathers much more extensive data than possible with traditional methods.
The vibration characteristics of the pumps and related hardware were analyzed using high resolution laser and photogrammetric digital imagery and digital strain mapping analysis to determine the characteristics that would ensure the long-term reliable and safe operation of the HVGO pumps. The stress and deformation analysis were performed on the operating pumps in a variety of normal (1280 m3/hr.) and upset operating conditions including under partial and full load conditions. Dynamic and modal analysis of the pumps was developed and analyzed. The displacement and tensor fields of the hardware including the pumps, bases and piping were measured using high resolution laser cameras and analyzed.
From the high-speed data gathering and loading analysis showed the deformation and stress affecting the pump and related hardware. The key variables undermining reliable performance were revealed and from the data the necessary remedial action was determined. The pumps have operated for over 30months to the time of writing without repeat failure.
This paper should be read in conjunction with PVP 2020-21203; Investigation and Resolution of the Fluid Structure Interaction of High Rate HVGO Pumps.
Dynamic Performance Analysis of Interfacial Cracks Near an Eccentric Elliptical Hole in Piezoelectric Bi-Materials Under Incident SH-Waves
Authors: An Ni , Song Tian-shu , Zhao Ming , Liu Yu , Hou Gangling 
Published: October 2020

Abstract
Piezoelectric materials have been widely used in modern science and technology due to their electro-mechanical coupling response. Sometimes, because of the stiff and brittle nature of some piezoelectric materials, the piezoelectric devices with defects may face fracture or failure during their service procedures. Therefore, it has become important to investigate the failure behaviors caused by defects, such as cracks and holes.
Based on the study of the dynamic anti-plane characteristics for radial crack emanating from a circular cavity in piezoelectric bi-materials, this paper aims to analyzes the dynamic incident anti-plane shearing (SH-wave) in piezoelectric bi-materials, which contains two interfacial cracks, near an eccentric elliptical hole. Green’s function method, the conformal mapping method, the interface conjunction techniques and the crack-deviation techniques are utilized to obtain a series of first kind Fredholm’s equations, based on which the dynamic stress intensity factor (DSIF) at the outer and the inner cracks’ tips are theoretically expressed. Numerical examples were graphically presented to illustrate the effects of the piezoelectric parameter, the effective piezoelectric elastic modulus, the dimensionless incident wave number and geometric parameters on the DSIF at both of the tips.
Previous studies are not comprehensive, especially when the center of the hole deviates from the interface. Therefore, the impact of eccentric distance on DSIF is considered in this paper. The solution of this problem provides a more accurate and efficient method for the investigation of dynamic fracture properties of piezoelectric materials and has an important theoretical significance in engineering design.
Structural Analysis Approach for the Defense Programs Package 3 (DPP-3)
Authors: Sakalaukus Peter J. , Barrett Nathan P. , Koeppel Brian J. 
Published: October 2020

Abstract
The Pacific Northwest National Laboratory (PNNL) is the design authority for a new Type B hazardous materials transportation package designated as the Defense Programs Package 3 (DPP-3) for the U.S. Department of Energy (DOE) National Nuclear Security Administration (NNSA). The DPP-3 has been developed using similar materials and fabrication methods employed in previous U.S. Nuclear Regulatory Commission (NRC), DOE, and NNSA certified packages. The DPP-3 design criteria are derived from the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code (BPVC), NNSA guidance and NRC regulatory guides in order to safely and securely transport a variety of payloads. Final regulatory approval by the NNSA will require regulatory testing to demonstrate that the containment vessel (CV) remains leaktight after enduring the entire regulatory testing sequence prescribed in Title 10 of the Code of Federal Regulations Part 71 (10 CFR 71). In order to gain confidence that the DPP-3 will remain leaktight after testing, the DPP-3 has been structurally analyzed using the Finite Element Analysis (FEA) software LS-DYNA. The FEA analyses serve two general purposes: first, they aid in design and development of the package, and second, they advise as to which drop orientations are expected to cause the most damage during regulatory testing. This paper will discuss how the design criteria are incorporated into analytical techniques needed to evaluate the FEA structural simulation results for 10 CFR 71 conditions to give confidence the DPP-3 testing campaign will be successful.
Experimental Investigation on Burst Pressure and Fatigue Life of Type IV LPG Cylinders
Authors: Wen Ange , Shen Chuanchuan , Hao Chunyong , Zheng Jinyang 
Published: October 2020

Abstract
Compared with the steel cylinders for liquefied petroleum gas (LPG), fully-wrapped fiber reinforced cylinders with non-metallic liners (type IV cylinders) have been widely used due to their advantages of light weight, corrosion resistance, low maintenance cost and no explosion when exposed in fire. However, for the heterogeneity of raw material performances and instability of manufacturing process, the mechanical performances of type IV cylinders show a certain dispersion. Therefore, in this study, a series of burst tests and pressure cycle tests on 89 type IV LPG cylinders (26.2 L, 2.1 MPa) were conducted to examine the performances of burst pressure and number of pressure cycles, and analyze the distribution characteristics. The total length of the experimental cylinder was 465 mm, the outer diameter and the thickness of the liner was 304 mm and 2 mm, respectively. Two types of cylinders were tested, with the thickness of composite overwrap in 2 mm and 4 mm, corresponding to the designed burst pressure of 12 MPa and 15 MPa. Burst test and pressure cycle test were conducted according to the standard GB/T 15385 and GB/T 9252, respectively. Results showed that the 59 cylinders had the similar crevasses morphology along the axial wall of liners after burst tests. Burst pressure of two design types fluctuated within the range of 11.4 MPa-12.5 MPa, and 13.7 MPa-16.0 MPa, respectively. The statistical results of burst pressure showed approximately normal distribution with a standard deviation of 0.263 MPa and 0.529 MPa. Also, the number of pressure cycles of 30 cylinders were all above 12,000 with a cycle frequency no more than 15 cycles per minute. Above studies have provided a data support for the recently published Chinese association standard T/CATSI 02 003-2019.