The Experts below are selected from a list of 309 Experts worldwide ranked by ideXlab platform
P Walstrom - One of the best experts on this subject based on the ideXlab platform.
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The Advanced Hydrotest Facility (AHF) large bore quadrupole focusing magnet system
IEEE Transactions on Applied Superconductivity, 2003Co-Authors: J H Schultz, A. Jason, P Walstrom, R J Camille, Timothy A Antaya, R L Myatt, J V Minervini, A Radovinsky, B A Smith, J A WaynertAbstract:The Advanced Hydrotest Facility (AHF) at Los Alamos will provide proton radiography of large-scale, dynamic events. The large bore (Case II) quadrupole focusing magnets are a subsystem in this facility, consisting of four complete imaging lines with a total of eight imaging plates and 52 quadrupole magnets. Each large bore quadrupole has an inner winding diameter of 660 mm and provides a gradient of 10.4 T/m with a 300 mm field of view. Each magnet is a two-layer saddle, contained by a three cm steel shell. The conductor is a Rutherford cable, soldered into a C-shaped copper channel. The magnets are cooled by the forced-flow of two-phase helium through coolant pipes. Since the winding was calculated to absorb bursts of 0.35 J/kg irradiation, both NbTi and Nb/sub 3/Sn designs are being considered.
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Magnetic design of large-bore superconducting quadrupoles for the AHF
IEEE Transactions on Applied Superconductivity, 2003Co-Authors: N. Andreev, V.s. Kashikhin, J. Tompkins, A. Jason, P.j. Limon, P WalstromAbstract:The Advanced Hydrotest Facility (AHF), under study by LANL, utilizes large-bore superconducting quadrupole magnets to image protons for radiography of fast events. The lens system uses two types of quadrupoles: a large bore (48-cm beam aperture) for wide field of view imaging and a smaller bore (23 cm aperture) for higher resolution images. The gradients of the magnets are 10.14 T/m and 18.58 T/m with magnetic lengths of 4.3 m and 3.0 m, respectively. The magnets are sufficiently novel to present a design challenge. Evaluation and comparisons were made for various types of magnet design: shell and racetrack coils, cold and warm iron, as well as an active superconducting shield. Nb/sub 3/Sn cable was considered as an alternative to NbTi to avoid quenching under high beam-scattering conditions. Several options are discussed and compared.
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advanced Hydrotest facility ahf large bore quadrupole focusing magnet system
Submitted to: International Cryogenic Engineering Conference Grenoble France July 22-26 2002, 2002Co-Authors: A. Jason, P Walstrom, J A Waynert, J H Schultz, R J Camille, Timothy A Antaya, R L Myatt, J V Minervini, A Radovinsky, B A SmithAbstract:The Advanced Hydrotest Facility (AHF) at Los Alamos will provide proton radiography of large-scale, dynamic events. The large bore (Case II) quadrupole focusing magnets are a subsystem in this facility, consisting of four complete imaging lines with a total of eight imaging plates and 52 quadrupole magnets. Each large bore quadrupole has an inner winding diameter of 660 mm and provides a gradient of 10.4 T/m with a 300 mm field of view. Each magnet is a two-layer saddle, contained by a three cm steel shell. The conductor is a Rutherford cable, soldered into a C-shaped copper channel. The magnets are cooled by the forced-flow of two-phase helium through coolant pipes. Since the winding must absorb bursts of 0.35 J/kg irradiation, both NbTi and Nb{sub 3}Sn designs are being considered.
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Design considerations of fast kicker systems for high intensity proton accelerators
PPPS-2001 Pulsed Power Plasma Science 2001. 28th IEEE International Conference on Plasma Science and 13th IEEE International Pulsed Power Conference. , 2001Co-Authors: W. Zhang, W.m. Parsons, P Walstrom, J. Sandberg, M.m. Murray, E. Cook, E. HartouniAbstract:In this paper, we discuss the specific issues related to the design of the fast kicker systems for high intensity proton accelerators. To address these issues in the preliminary design stage can be critical since the fast kicker systems affect the machine lattice structure and overall design parameters. Main topics include system architecture, design strategy, beam current coupling, grounding, end user cost vs. system cost, reliability, redundancy and flexibility. Operating experience with the Alternating Gradient Synchrotron injection and extraction kicker systems at Brookhaven National Laboratory and their future upgrade is presented. Additionally, new conceptual designs of the extraction kicker for the Spallation Neutron Source at Oak Ridge and the Advanced Hydrotest Facility at Los Alamos are discussed.
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Design considerations of fast kicker systems for high intensity proton accelerators
IEEE Conference Record - Abstracts. PPPS-2001 Pulsed Power Plasma Science 2001. 28th IEEE International Conference on Plasma Science and 13th IEEE Int, 2001Co-Authors: W. Zhang, W.m. Parsons, P Walstrom, J. Sandberg, E. CookAbstract:Summary form only given. In this paper, we will discuss the specific issues related to the design of the Fast Kicker Systems for high intensity proton accelerators. To address these issues in the preliminary design stage can be critical since the fast kicker systems affect the machine lattice structure and overall design parameters. Main topics will include system architecture, design strategy, beam current coupling, grounding, end user cost vs. system cost, reliability, redundancy and flexibility. Operating experience with the Alternate Gradient Synchrotron injection and extraction kicker systems at Brookhaven National Laboratory and their future upgrade will be presented. Additionally, a new conceptual design of the extraction kicker for the Spallation Neutron Source at Oak Ridge and the Advanced Hydrotest Facility at Los Alamos will be discussed.
Tingyue Gu - One of the best experts on this subject based on the ideXlab platform.
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mitigating microbiologically influenced corrosion of an oilfield biofilm consortium on carbon steel in enriched Hydrotest fluid using 2 2 dibromo 3 nitrilopropionamide dbnpa enhanced by a 14 mer peptide
Journal of Materials Science & Technology, 2020Co-Authors: Di Wang, Suchada Punpruk, Sith Kumseranee, Mahmoud Ramadan, Tingyue GuAbstract:Abstract In the oil and gas industry, microbiologically influenced corrosion (MIC) is a major threat to Hydrotest, a procedure which is required to certify whether a pipeline can be commissioned. Seawater is frequently used as a Hydrotest fluid. In this biofilm prevention lab study, an oilfield biofilm consortium was grown in an enriched artificial seawater anaerobically at 37 °C for 60 days. The combination of 100 ppm (w/w) 2,2-dibromo-3-nitrilopropionamide (DBNPA) + 100 nM (180 ppb) Peptide A (a biofilm dispersal agent) led to extra SRB (sulfate reducing bacteria), APB (acid producing bacteria) and GHB (general heterotrophic bacteria) sessile cell count reductions of 0.9-log, 0.8-log and 0.6-log, respectively, compared with the outcome obtained by using 100 ppm DBNPA only. The Peptide A enhancement also led to extra reductions of 44 % in weight loss, 43 % in maximum pit depth, and 54 % in corrosion current density.
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laboratory investigation of microbiologically influenced corrosion of carbon steel in Hydrotest using enriched artificial seawater inoculated with an oilfield biofilm consortium
Engineering Failure Analysis, 2019Co-Authors: Tuba Unsal, Sith Kumseranee, Suchada Punpruk, Tingyue GuAbstract:Abstract Microbiologically Influenced Corrosion (MIC) is a major concern in Hydrotest using untreated water. The Hydrotesting process itself may last only hours, but the Hydrotest water is often shut in for weeks or months. This allows biofilms to grow on pipe walls, which may eventually lead to pinhole leaks after the pipeline is commissioned. This laboratory study investigated MIC in Hydrotest using an oilfield biofilm consortium to inoculate enriched artificial seawater to simulate Hydrotest fluid. C1018 carbon steel coupons were placed in 120 mL anaerobic vials for incubation at 37 °C for up to 60 days. Experimental results showed that sulfate reducing bacteria (SRB), general heterotrophic bacteria (GHB) and acid producing bacteria (APB) formed robust biofilms on coupons that led to a weight loss of 7.1 ± 0.3 mg/cm2 and maximum pit depth of 33.5 μm after 60 days. Electrochemical measurements were found to be consistent with the corrosion data.
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laboratory investigation of mic threat due to Hydrotest using untreated seawater and subsequent exposure to pipeline fluids with and without srb spiking
Engineering Failure Analysis, 2013Co-Authors: D Xu, Weiji Huang, G Ruschau, Jennifer Hornemann, Tingyue GuAbstract:Abstract Microbiologically Influenced Corrosion (MIC) is a major threat to integrities of pipelines and storage tanks. Even though MIC during Hydrotest itself may be limited due to lack of nutrients and a relatively short duration, biofilms left behind may flourish after a pipeline or storage tank is commissioned, resulting in failures due to MIC pinhole leaks over the long run. This work investigated MIC threats in simulated Hydrotest with X65 coupons using untreated natural seawater and enriched artificial seawater spiked or not spiked with a laboratory strain of Sulfate Reducing Bacteria (SRB) for up to 90 days. The MIC threat after Hydrotested pipes were subsequently exposed to pipeline fluids was also investigated by using simulated pipeline fluids containing a mixture of LVT-200 oil, natural seawater and CO 2 or a mixture of LVT-200 oil, simulated formation water (65,000 ppm (w/w) NaCl, 22 mM SO 4 2 - ) and CO 2 . Tests were performed at 22 °C and 37 °C in anaerobic vials. The effectiveness of a 30 min slug of Tetrakis Hydroxymethyl Phosphonium Sulfate (THPS) treatment of the coupons right after Hydrotest was also evaluated. MIC pitting was observed in simulated Hydrotest using enriched artificial seawater spiked with SRB. MIC pitting was also observed on coupons exposed to simulated pipeline fluids after Hydrotesting with SRB spiking using either natural seawater or enriched artificial seawater.
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LABORATORY INVESTIGATION OF MIC IN HydrotestING USING SEAWATER
Corrosion, 2010Co-Authors: Kaili Zhao, Tingyue Gu, Ivan Cruz, Ardjan KoplikuAbstract:Microbiologically Induced Corrosion (MIC) is a potential threat associated with Hydrotesting. It has been established that Sulfate Reducing Bacteria (SRB) can utilize hydrocarbons or even live on CO2 – H2 autotrophically. Pitting due to MIC during Hydrotesting itself may not be a serious problem, because its duration is limited to several days or months. The biofilms left behind after the Hydrotest may present a serious threat once the pipelines are commissioned and used for many years, because pipeline fluids may contain a sufficient amount of nutrients for biofilms to flourish. This laboratory investigation was conducted to study the MIC threat in Hydrotests using seawater. Arabian and Gulf of Mexico (GoM) seawater samples were collected from offshore locations. Quantitative PCR (Polymerase Chain Reaction) analysis was used to detect SRB in seawater samples. It was found that offshore GoM “clean seawater” did not contain a sufficient amount of organic carbons to support the rapid growth of biofilms. Enriched seawater spiked with SRB was used to speed up biofilm growth. An MIC prediction software program based on the mechanistic Biocatalytic Cathodic Sulfate Reduction (BCSR) theory was able to predict longer term SRB pitting using short-term pitting data in laboratory experiments for MIC in Hydrotest.
S.j. Chang - One of the best experts on this subject based on the ideXlab platform.
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Probability of Fracture and Life Extension Estimate of the High-Flux Isotope Reactor Vessel
Journal of Pressure Vessel Technology-transactions of The Asme, 1998Co-Authors: S.j. ChangAbstract:The state of the vessel steel embrittlement as a result of neutron irradiation can be measured by its increase in ductile-brittle transition temperature (DBTT)for fracture, often denoted by RT NDT for carbon steel. This transition temperature can be calibrated by the drop-weight test and, sometimes, by the Charpy impact test. The life extension for the high-flux isotope reactor (HFIR) vessel is calculated by using the method of fracture mechanics that is incorporated with the effect of the DBTT change. The failure probability of the HFIR vessel is limited as the life of the vessel by the reactor core melt probability of 10 -4 . The operating safety of the reactor is ensured by periodic hydrostatic pressure test (Hydrotest). The Hydrotest is performed in order to determine a safe vessel static pressure. The fracture probability as a result of the hydrostatic pressure test is calculated and is used to determine the life of the vessel. Failure to perform Hydrotest imposes the limit on the life of the vessel. The conventional method of fracture probability calculations such as that used by the NRCsponsored PRAISE CODE and the FAVOR CODE developed in this Laboratory are based on the Monte Carlo simulation. Heavy computations are required. An alternative method of fracture probability calculation by direct probability integration is developed in this paper. The present approach offers simple and expedient ways to obtain numerical results without losing any generality. This approach provides a clear analytical expression on the physical random variables to be integrated, yet requires much less computation time. In this paper, numerical results on 1) the probability of vessel fracture, 2) the Hydrotest time interval, and 3) the Hydrotest pressure as a result of the DBTT increase are obtained. Limiting the probabilities of the vessel fracture as a result of Hydrotest to 10 -4 implies that the reactor vessel life can be extended up to 50 EFPY (100 MW) with the minimum vessel operating temperature equal to 85°F.
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Probabilistic fracture mechanics analysis for the life extension estimate of the high flux isotope reactor vessel
1997Co-Authors: S.j. ChangAbstract:The state of the vessel steel embrittlement as a result of neutron irradiation can be measured by its increase in the nil ductility temperature (NDT). This temperature is sometimes referred to as the brittle-ductile transition temperature (DBT) for fracture. The life extension of the High Flux Isotope Reactor (HFIR) vessel is calculated by using the method of fracture mechanics. A new method of fracture probability calculation is presented in this paper. The fracture probability as a result of the hydrostatic pressure test (Hydrotest) is used to determine the life of the vessel. The Hydrotest is performed in order to determine a safe vessel static pressure. It is then followed by using fracture mechanics to project the safe reactor operation time from the time of the satisfactory hydrostatic test. The life extension calculation provides the following information on the remaining life of the reactor as a function of the NDT increase: (1) the life of the vessel is determined by the probability of vessel fracture as a result of Hydrotest at several Hydrotest pressures and vessel embrittlement conditions, (2) the Hydrotest time interval vs the NDT increase rate, and (3) the Hydrotest pressure vs the NDT increase rate. It is understood that the use of a complete range of uncertainties of the NDT increase is equivalent to the entire range of radiation damage that can be experienced by the vessel steel. From the numerical values for the probabilities of the vessel fracture as a result of Hydrotest, it is estimated that the reactor vessel life can be extended up to 50 EFPY (100 MW) with the minimum vessel operating temperature equal to 85{degrees}F.
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The method of life extension for the High Flux Isotope Reactor vessel
1995Co-Authors: S.j. ChangAbstract:The state of the vessel steel embrittlement as a result of neutron irradiation can be measured by its increase in the nil ductility temperature (NDT). This temperature is sometimes referred to as the brittle-ductile transition temperature (DBT) for fracture. The life extension of the High Flux Isotope Reactor (HFIR) vessel is calculated by using the method of fracture mechanics. A hydrostatic pressure test (Hydrotest) is performed in order to determine a safe vessel static pressure. It is then followed by using fracture mechanics to project the reactor life from the safe hydrostatic pressure. The life extension calculation provides the following information on the remaining life of the reactor as a function of the nil ductility temperature increase: the probability of vessel fracture due to Hydrotest vs vessel life at several Hydrotest pressures; the Hydrotest time interval vs the uncertainty of the nil ductility temperature increase rate; and the Hydrotest pressure vs the uncertainty of the nil ductility temperature increase rate. It is understood that the use of a complete range of uncertainties of the nil ductility temperature increase is equivalent to the entire range of radiation damage that can be experienced by the vessel steel. From the numerical values for the probabilities of the vessel fracture as a result of Hydrotest, it is estimated that the reactor vessel life can be extended up to 50 EFPY (100 MW) with the minimum vessel operating temperature equal to 85{degree}F.
R Sahney - One of the best experts on this subject based on the ideXlab platform.
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Hydrotest protocol for applications involving lower toughness steels
2004 International Pipeline Conference Volumes 1 2 and 3, 2004Co-Authors: B N Leis, R D Galliher, R L Sutherby, R SahneyAbstract:Hydrotesting has been used by the transmission pipeline industry for decades, and remains the only effective means to control stress-corrosion cracking until in-line inspection is proven. This paper addresses the conditions for effective proof-pressure testing in terms of ductile fracture referenced to peak pressure and hold-time, and then contrasts these to the response in low-toughness situations. Fracture properties typical of an early-vintage electrical-resistance weld (ERW) seam were determined and used as the basis to simulate the response at toughness levels typical of some lower-toughness steels. Fracture properties characterized via Charpy-vee notch (CVN) energy showed low energy to failure, and confined inelastic response characteristic of linear-elastic fracture mechanics. Hydrotest and service breaks associated with cracking in an ERW seam showed a very small shear lip and often showed chevrons pointing back toward the origins — features consistent with the CVN results and characteristic of low fracture ductility. The results indicate Hydrotest protocols derived and effective for ductile fracture are not directly applicable when brittle-like fracture controls. Hydrotesting was indicated to be an effective means to expose defects in ERW seams, as rupture is indicated to occur under typical Hydrotest conditions. Simulated growth of the scope of defect lengths and depths evident along Hydrotest breaks showed virtually no time dependent cracking, which means the hold time at maximum pressure should be reduced to the minimum time required to ensure all pipe in the test section has reached its target pressure.Copyright © 2004 by ASME
B N Leis - One of the best experts on this subject based on the ideXlab platform.
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Hydrotest protocol for applications involving lower toughness steels
2004 International Pipeline Conference Volumes 1 2 and 3, 2004Co-Authors: B N Leis, R D Galliher, R L Sutherby, R SahneyAbstract:Hydrotesting has been used by the transmission pipeline industry for decades, and remains the only effective means to control stress-corrosion cracking until in-line inspection is proven. This paper addresses the conditions for effective proof-pressure testing in terms of ductile fracture referenced to peak pressure and hold-time, and then contrasts these to the response in low-toughness situations. Fracture properties typical of an early-vintage electrical-resistance weld (ERW) seam were determined and used as the basis to simulate the response at toughness levels typical of some lower-toughness steels. Fracture properties characterized via Charpy-vee notch (CVN) energy showed low energy to failure, and confined inelastic response characteristic of linear-elastic fracture mechanics. Hydrotest and service breaks associated with cracking in an ERW seam showed a very small shear lip and often showed chevrons pointing back toward the origins — features consistent with the CVN results and characteristic of low fracture ductility. The results indicate Hydrotest protocols derived and effective for ductile fracture are not directly applicable when brittle-like fracture controls. Hydrotesting was indicated to be an effective means to expose defects in ERW seams, as rupture is indicated to occur under typical Hydrotest conditions. Simulated growth of the scope of defect lengths and depths evident along Hydrotest breaks showed virtually no time dependent cracking, which means the hold time at maximum pressure should be reduced to the minimum time required to ensure all pipe in the test section has reached its target pressure.Copyright © 2004 by ASME
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Hydrotest strategies for gas transmission pipelines based on ductile flaw growth considerations
1992Co-Authors: B N Leis, F W BrustAbstract:The objective of this study was to determine the growth of various flaw sizes as a result of having been subjected to combinations of test pressures and hold times and to assess the subsequent serviceability of pipelines containing those flaws in gas-transmission service. The purpose of the flaw-growth calculations is to define Hydrotest procedures for gas-transmission pipelines that remove flaws that could become critical in service while minimizing the growth of any remaining flaws. This report is the fourth in a series of topical reports dealing with quasi-static ductile flaw growth in pipelines, such as can occur in a Hydrotest. Prior reports presented relevant material properties, the theoretical analysis, and the model development and validation. This report presents the results and analysis of an extensive parametric study of ductile flaw growth as a function of maximum test pressure, hold time, flaw geometry, and strength and toughness of the pipe steel representative of submerged-arc welded pipe in grades from X52 through X70 with a yield-to-ultimate ratio less than 0.90.
