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Sample records for cryosorption vacuum pumping

  1. Investigation of cryosorption vacuum system and operation process for COIL

    NASA Astrophysics Data System (ADS)

    Xia, Liang-zhi; Wang, Jin-qu; Sang, Feng-ting; Zhao, Su-qin; Jin, Yu-qi; Fang, Ben-jie

    2007-05-01

    Cryosorption vacuum system for COIL is researched and developed. Adsorption chiller has been proposed and developed by improving the heat exchanger chiller. Compared with the heat exchanger chiller, the volume and LN II consumption of the new chiller were favourably reduced. In the present work, the new adsorption operation process, cryogenic pressure swing adsorption is adopted. Compared with thermal swing adsorption, regeneration time is shortened and LN II consumption is saved at least 80% in the new operation process. The cryosorption vacuum system was integrated to COIL and tested successfully. The weight of sorbent in adsorption bed is 22Kg, the total gas flowrate is about 0.5mol/s, the COIL's power maintains over 2kW, the total COIL's working time accounts to 100 seconds. It is concluded that the cryosorption vacuum system has the same pressure recovery capability as the large vacuum tank.

  2. Performance studies of Cryocooler based cryosorption pumps with indigenous activated carbons for fusion applications

    NASA Astrophysics Data System (ADS)

    Kasthurirengan, S.; Vivek, G. A.; Verma, Ravi; Behera, Upendra; Udgata, Swarup; Gangradey, Ranjana

    2017-02-01

    Cryosorption pumps are the only solution for pumping helium and hydrogen in fusion systems, due to their high pumping speeds and suitability in harsh environments. Their development requires the right Activated Carbons (ACs) and suitable adhesives to bind them to metallic panels with liquid helium (LHe) flow channels. However, their performance evaluation will require large quantities of LHe. Alternatively, these pumps can be built with small size panels adhered with ACs and cooled by a cryocooler. The paper describes the development of a cryopump using a commercial cryocooler (Sumitomo RDK415D), with 1.5W@4.2 K, integrated with small size AC panel mounted on 2nd stage, with the 1st stage acting as radiation shield. Under no load, the cryopump reaches the ultimate pressure of 2.1E-7 mbar. The pump is built using panels with different indigenously developed ACs such as granules, pellets, ACF-FK2 and activated carbon of knitted IPR cloth. We present the experimental results of pumping speeds for gases such as nitrogen, argon and helium using the procedures outlined by American Vacuum Society (AVS). These studies will enable to arrive at the right ACs and adhesives for the development of large scale cryosorption pumps with liquid helium flow.

  3. Metal sponge for cryosorption pumping applications

    DOEpatents

    Myneni, G.R.; Kneisel, P.

    1995-12-26

    A system has been developed for adsorbing gases at high vacuum in a closed area. The system utilizes large surface clean anodized metal surfaces at low temperatures to adsorb the gases. The large surface clean anodized metal is referred to as a metal sponge. The metal sponge generates or maintains the high vacuum by increasing the available active cryosorbing surface area. 4 figs.

  4. Metal sponge for cryosorption pumping applications

    DOEpatents

    Myneni, Ganapati R.; Kneisel, Peter

    1995-01-01

    A system has been developed for adsorbing gases at high vacuum in a closed area. The system utilizes large surface clean anodized metal surfaces at low temperatures to adsorb the gases. The large surface clean anodized metal is referred to as a metal sponge. The metal sponge generates or maintains the high vacuum by increasing the available active cryosorbing surface area.

  5. Measurement of thermal conductivity of materials down to 4.5 K for development of cryosorption pumps

    NASA Astrophysics Data System (ADS)

    Verma, Ravi; Behera, Upendra; Kasthurirengan, S.; Shivaprakash, N. C.; Udgata, S. S.; Gangradey, R.

    2017-02-01

    Cryosorption pumps belong to the class of entrapment or capture vacuum pumps and they retain the gas molecules by sorption and / or by condensation on its internal surfaces. An important aspect in their development is the proper adhesion of the activated carbon granules onto the metallic panel and their cooling to the lowest possible temperature by using high thermal conductivity adhesives for adhering the activated carbons. Hence, the thermal conductivity data of the select adhesives and activated carbons down to 4.5 K are quite essential, but they are not available in open literature. Towards this, an experimental setup has been developed to measure the thermal conductivities of samples with high or low thermal conductivities from 300 K to 4.5 K, with liquid helium using a Janis SuperVariTemp cryostat. This paper presents the details of the experimental setup and the results of our studies on (i) standard samples and (ii) epoxy based adhesives samples. The above studies will enable to make the right choice of adhesives for the development of cryosorption pumps.

  6. TIMO-2-A cryogenic test bed for the ITER cryosorption pumps

    NASA Astrophysics Data System (ADS)

    Haas, Horst; Day, Christian; Herzog, Friedhelm

    2012-06-01

    The Karlsruhe Institute of Technology (KIT) has been carrying out research and development in the field of vacuum cryopumps for nuclear fusion devices over the last decade. Together with the development activities also experience in the operation of the needed cryogenic systems necessary for such type of large scale cryopumps was collected. Due to the specific requirements of a large fusion device, such as ITER, the cryogenic distribution is based on gaseous helium at the needed temperature levels rather than liquid nitrogen or liquid helium. KIT has set up a large scale research facility, called TIMO-2, fully equipped with supercritical helium supply at large flow rates to be able to perform cryogenic tests of components under ITER-relevant conditions. During first test campaigns at TIMO-2 with a large scale model cryopump the ITER cryosorption vacuum pumping concept was successfully validated. After major refurbishments and upgrades, the TIMO-2 facility is now ready for the acceptance tests of the ITER torus cryopump. This paper describes the modified test facility TIMO-2 with particular attention to the available cryogenic supply at different temperature levels. The new 100 K helium supply facility will be described in detail.

  7. High specific surface area aerogel cryoadsorber for vacuum pumping applications

    DOEpatents

    Hill, Randal M.; Fought, Eric R.; Biltoft, Peter J.

    2000-01-01

    A cryogenic pumping system is provided, comprising a vacuum environment, an aerogel sorbent formed from a carbon aerogel disposed within the vacuum environment, and cooling means for cooling the aerogel sorbent sufficiently to adsorb molecules from the vacuum environment onto the aerogel sorbent. Embodiments of the invention include a liquid refrigerant cryosorption pump, a compressed helium cryogenic pump, a cryopanel and a Meissner coil, each of which uses carbon aerogel as a sorbent material.

  8. Experimental clarification of the desorption of H 2, D 2 and He mixtures from cryosorption pumps

    NASA Astrophysics Data System (ADS)

    Terashita, Masashi; Fukada, Satoshi

    2011-10-01

    The behavior of dynamic desorption of He, H 2 and D 2 from a cryosorption pump is experimentally investigated for simplified rough separation of D-T fuel exhaust from impurities. As a fundamental study to separate the unburned D-T fuel and impurities dynamically, the discharge rates of H 2 and D 2 (as a representative of T 2), He (as a major impurity) are determined as a function of time and temperature, when the cryosorption pump is regenerated from 10 K to the room temperature of 285-305 K. The release behavior of H 2 and D 2 is compared, and the desorption isotherms of H 2, D 2 and He for activated carbon used in the cryosorption pump are determined from their respective discharge curves. The present result may lead to provide a simplified technique to decrease the throughput of the following fuel purification system and to decrease the tritium inventory by rapid separation of the D-T fuel from impurities.

  9. Studies of adsorption characteristics of activated carbons down to 4.5 K for the development of cryosorption pumps for fusion systems

    NASA Astrophysics Data System (ADS)

    Kasthurirengan, S.; Behera, U.; Vivek, G. A.; Krishnamoorthy, V.; Gangradey, R.; Udgata, S. S.; Tripati, V. S.

    2014-01-01

    Cryosorption pump is the only possible device to pump helium, hydrogen and its isotopes in fusion environment, such as high magnetic field and high plasma temperatures. Activated carbons are known to be the most suitable adsorbent in the development of cryosorption pumps. For this purpose, the data of adsorption characteristics of activated carbons in the temperature range 4.5 K to 77 K are needed, but are not available in the literature. For obtaining the above data, a commercial micro pore analyzer operating at 77 K has been integrated with a two stage GM cryocooler, which enables the cooling of the sample temperature down to 4.5 K. A heat switch mounted between the second stage cold head and the sample chamber helps to raise the sample chamber temperature to 77 K without affecting the performance of the cryocooler. The detailed description of this system is presented elsewhere. This paper presents the results of experimental studies of adsorption isotherms measured on different types of activated carbons in the form of granules, globules, flake knitted and non-woven types in the temperature range 4.5 K to 10 K using Helium gas as the adsorbate. The above results are analyzed to obtain the pore size distributions and surface areas of the activated carbons. The effect of adhesive used for bonding the activated carbons to the panels is also studied. These results will be useful to arrive at the right choice of activated carbon to be used for the development of cryosorption pumps.

  10. Studies of adsorption characteristics of activated carbons down to 4.5 K for the development of cryosorption pumps for fusion systems

    SciTech Connect

    Kasthurirengan, S.; Behera, U.; Vivek, G. A.; Krishnamoorthy, V.; Gangradey, R.; Udgata, S. S.; Tripati, V. S.

    2014-01-29

    Cryosorption pump is the only possible device to pump helium, hydrogen and its isotopes in fusion environment, such as high magnetic field and high plasma temperatures. Activated carbons are known to be the most suitable adsorbent in the development of cryosorption pumps. For this purpose, the data of adsorption characteristics of activated carbons in the temperature range 4.5 K to 77 K are needed, but are not available in the literature. For obtaining the above data, a commercial micro pore analyzer operating at 77 K has been integrated with a two stage GM cryocooler, which enables the cooling of the sample temperature down to 4.5 K. A heat switch mounted between the second stage cold head and the sample chamber helps to raise the sample chamber temperature to 77 K without affecting the performance of the cryocooler. The detailed description of this system is presented elsewhere. This paper presents the results of experimental studies of adsorption isotherms measured on different types of activated carbons in the form of granules, globules, flake knitted and non-woven types in the temperature range 4.5 K to 10 K using Helium gas as the adsorbate. The above results are analyzed to obtain the pore size distributions and surface areas of the activated carbons. The effect of adhesive used for bonding the activated carbons to the panels is also studied. These results will be useful to arrive at the right choice of activated carbon to be used for the development of cryosorption pumps.

  11. Vacuum pump aids ejectors

    SciTech Connect

    Nelson, R.E.

    1982-12-01

    The steam ejector/vacuum pump hybrid system has been operating satisfactorily since the summer of 1981. This system has essentially been as troublefree as the all-ejector system and, of course, has provided a substantial cost savings. Construction is currently under way to convert the vacuum system of another crude still which is equipped with steam ejectors and barometric condensers to the hybrid system of steam ejectors, surface condensers, and vacuum pumps. This current project is even more financially attractive because it allows a dirty water cooling tower which serves the barometric condensers to be shut down. Providing a vacuum for crude distillation vacuum towers with this hybrid system is by no means the only application of this technique. Any vacuum system consisting of all steam ejectors would be a candidate for this hybrid system and the resulting savings in energy.

  12. MOLECULAR VACUUM PUMP

    DOEpatents

    Eckberg, E.E.

    1960-09-27

    A multiple molecular vacuum pump capable of producing a vacuum of the order of 10/sup -9/ mm Hg is described. The pump comprises a casing of an aggregate of paired and matched cylindrical plates, a recessed portion on one face of each plate concentrically positioned formed by a radially extending wall and matching the similarly recessed portion of its twin plate of that pair of plates and for all paired and matched plates; a plurality of grooves formed in the radially extending walls of each and all recesses progressing in a spiral manner from their respective starting points out at the periphery of the recess inwardly to the central area; a plurality of rotors rotatably mounted to closely occupy the spaces as presented by the paired and matched recesses between all paired plates; a hollowed drive-shaft perforated at points adjacent to the termini of all spiral grooves; inlet ports at the starting points of all grooves and through all plates at common points to each respectively; and a common outlet passage presented by the hollow portion of the perforated hollowed drive-shaft of the molecular pump. (AEC)

  13. The solar vacuum water pump

    SciTech Connect

    Ryduchowski, K.W.

    1983-12-01

    In this paper the conception of the solar vacuum water pump is presented. The working medium of the pump consists of the water vapour with temperature about 100/sup 0/C, which is produced by solar energy Fresnel-lens collector. The pressure difference between the condensing chamber /3/ and ambient atmosphere caused by the direct condensation of the water vapour at the surface of the pumped water, creates the necessary pumping force.

  14. SHINE Vacuum Pump Test Verification

    SciTech Connect

    Morgan, Gregg A; Peters, Brent

    2013-09-30

    Normetex pumps used world-wide for tritium service are no longer available. DOE and other researchers worldwide have spent significant funds characterizing this pump. Identification of alternate pumps is required for performance and compatibility with tritium gas. Many of the pumps that could be used to meet the functional performance requirements (e.g. pressure and flow conditions) of the Normetex pump have features that include the use of polymers or oils and greases that are not directly compatible with tritium service. This study assembles a test system to determine the flow characteristics for candidate alternate pumps. These tests are critical to the movement of tritium through the SHINE Tritium Purification System (TPS). The purpose of the pump testing is two-fold: (1) obtain baseline vacuum pump characteristics for an alternate (i.e. ''Normetex replacement'') pump intended for use in tritium service; and (2) verify that low pressure hydrogen gas can be transported over distances up to 300 feet by the candidate pumps. Flow rates and nominal system pressures have been identified for the SHINE Mo-99 production process Tritium Purification System (TPS). To minimize the line sizes for the transfer of low pressure tritium from the Neutron Driver Accelerator System (NDAS) to the primary processing systems in the TPS, a ''booster'' pump has been located near the accelerator in the design. A series of pump tests were performed at various configurations using hydrogen gas (no tritium) to ensure that this concept is practical and maintains adequate flow rates and required pressures. This report summarizes the results of the tests that have been performed using various pump configurations. The current design of the Tritium Purification System requires the ''booster'' pump to discharge to or to be backed by another vacuum pump. Since Normetex pumps are no longer manufactured, a commercially available Edwards scroll pump will be used to back the booster pump. In this

  15. Demonstrations with a Vacuum: Old Demonstrations for New Vacuum Pumps.

    ERIC Educational Resources Information Center

    Greenslade, Thomas B., Jr.

    1989-01-01

    Explains mechanisms of 19th-century vacuum pumps. Describes demonstrations using the pump including guinea and feather tube, aurora tube, electric egg, Gassiots cascade, air mill, bell in vacuum, density and buoyancy of air, fountain in vacuum, mercury shower, palm and bladder glasses, Bacchus demonstration, pneumatic man-lifter, and Magdeburg…

  16. MEMS ion-sorption high vacuum pump

    NASA Astrophysics Data System (ADS)

    Grzebyk, T.; Knapkiewicz, P.; Szyszka, P.; Gorecka-Drzazga, A.; Dziuban, J. A.

    2016-11-01

    In the article a miniature MEMS-type ion-sorption vacuum pump has been presented. The influence of electric and magnetic field, as well as horizontal and vertical dimensions of the micropump and type of material used for electrodes on the pump properties has been investigated. It has been found that the micropump works efficiently as long as the magnetic field is higher than 0.3 T, and pumping cell is larger than 1x1x1 mm3. The pump allows generating vacuum at the level of 10-7-10-9 hPa in 100 mm3 volume.

  17. Evaluation of Dry, Rough Vacuum Pumps

    NASA Technical Reports Server (NTRS)

    Hunter, Brian

    2006-01-01

    This document provides information on the testing and evaluation of thirteen dry rough vacuum pumps of various designs and from various manufacturers. Several types of rough vacuum pumps were evaluated, including scroll, roots, and diaphragm pumps. Tests included long term testing, speed curve generation, voltage variance, vibrations emissions and susceptibility, electromagnetic interference emissions and susceptibility, static leak rate, exhaust restriction, response/recovery time tests, and a contamination analysis for scroll pumps. Parameters were found for operation with helium, which often is not provided from the manufacturer

  18. Mass spectrometer vacuum housing and pumping system

    DOEpatents

    Coutts, Gerald W.; Bushman, John F.; Alger, Terry W.

    1996-01-01

    A vacuum housing and pumping system for a portable gas chromatograph/mass spectrometer (GC/MS). The vacuum housing section of the system has minimum weight for portability while designed and constructed to utilize metal gasket sealed stainless steel to be compatible with high vacuum operation. The vacuum pumping section of the system consists of a sorption (getter) pump to remove atmospheric leakage and outgassing contaminants as well as the gas chromatograph carrier gas (hydrogen) and an ion pump to remove the argon from atmospheric leaks. The overall GC/MS system has broad application to contaminants, hazardous materials, illegal drugs, pollution monitoring, etc., as well as for use by chemical weapon treaty verification teams, due to the light weight and portability thereof.

  19. Mass spectrometer vacuum housing and pumping system

    DOEpatents

    Coutts, G.W.; Bushman, J.F.; Alger, T.W.

    1996-07-23

    A vacuum housing and pumping system is described for a portable gas chromatograph/mass spectrometer (GC/MS). The vacuum housing section of the system has minimum weight for portability while designed and constructed to utilize metal gasket sealed stainless steel to be compatible with high vacuum operation. The vacuum pumping section of the system consists of a sorption (getter) pump to remove atmospheric leakage and outgassing contaminants as well as the gas chromatograph carrier gas (hydrogen) and an ion pump to remove the argon from atmospheric leaks. The overall GC/MS system has broad application to contaminants, hazardous materials, illegal drugs, pollution monitoring, etc., as well as for use by chemical weapon treaty verification teams, due to the light weight and portability thereof. 7 figs.

  20. Pneumatically Actuated Miniature Peristaltic Vacuum Pumps

    NASA Technical Reports Server (NTRS)

    Feldman, Sabrina; Feldman, Jason; Svehla, Danielle

    2003-01-01

    Pneumatically actuated miniature peristaltic vacuum pumps have been proposed for incorporation into advanced miniature versions of scientific instruments that depend on vacuum for proper operation. These pumps are expected to be capable of reaching vacuum-side pressures in the torr to millitorr range (from .133 down to .0.13 Pa). Vacuum pumps that operate in this range are often denoted roughing pumps. In comparison with previously available roughing pumps, these pumps are expected to be an order of magnitude less massive and less power-hungry. In addition, they would be extremely robust, and would operate with little or no maintenance and without need for oil or other lubricants. Portable mass spectrometers are typical examples of instruments that could incorporate the proposed pumps. In addition, the proposed pumps could be used as roughing pumps in general laboratory applications in which low pumping rates could be tolerated. The proposed pumps could be designed and fabricated in conventionally machined and micromachined versions. A typical micromachined version (see figure) would include a rigid glass, metal, or plastic substrate and two layers of silicone rubber. The bottom silicone layer would contain shallow pump channels covered by silicone arches that could be pushed down pneumatically to block the channels. The bottom silicone layer would be covered with a thin layer of material with very low gas permeability, and would be bonded to the substrate everywhere except in the channel areas. The top silicone layer would be attached to the bottom silicone layer and would contain pneumatic- actuation channels that would lie crosswise to the pump channels. This version is said to be micromachined because the two silicone layers containing the channels would be fabricated by casting silicone rubber on micromachined silicon molds. The pneumatic-actuation channels would be alternately connected to a compressed gas and (depending on pump design) either to atmospheric

  1. A High Vacuum High Speed Ion Pump

    DOE R&D Accomplishments Database

    Foster, J. S. Jr.; Lawrence, E. O.; Lofgren, E. J.

    1952-08-27

    A vacuum pump based on the properties of a magnetically collimated electric discharge is described. It has a speed in the range 3000 to 7000 liters a second and a base pressure in the order of 10{sup -6} mm. (auth)

  2. TFCX pumped limiter and vacuum pumping system design and analysis

    SciTech Connect

    Haines, J.R.

    1985-04-01

    Impurity control system design and performance studies were performed in support of the Tokamak Fusion Core Experiment (TFCX) pre-conceptual design. Efforts concentrated on pumped limiter and vacuum pumping system design configuration, thermal/mechanical and erosion lifetime performance of the limiter protective surface, and helium ash removal performance. The reference limiter design forms a continuous toroidal belt at the bottom of the device and features a flat surface with a single leading edge. The vacuum pumping system features large vacuum ducts (diameter approximately 1 m) and high-speed, compound cryopumps. Analysis results indicate that the limiter/vacuum pumping system design provides adequate helium ash removal. Erosion, primarily by disruption-induced vaporization and/or melting, limits the protective surface lifetime to about one calendar year or only about 60 full-power hours of operation. In addition to evaluating impurity control system performance for nominal TFCX conditions, these studies attempt to focus on the key plasma physics and engineering design issues that should be addressed in future research and development programs.

  3. Extended ion pumped vacuum friction test

    NASA Technical Reports Server (NTRS)

    Hammel, R. L.

    1971-01-01

    Boundary layer friction data under ion pumped vacuum was taken for sixteen material couples. The test series was an extension of a previous study of the effects of modified ion pumped environments. Sliding distances imposed in the present effort greatly exceeded any studied in the previous contiguous, flight or ground tests. Wear out of specific couples, in particular, thin film lubricants was noted. The behavior of the test hardware including wear out of the mechanisms was noted. As a result, the impact of test interruption was observed for several test couples. Recovery of the friction upon re-establishing sliding in vacuum was generally rapid. The results of the extended sliding study reinforce the previous conclusion that sliding distance (mechanical history) is the primary factor in establishing the force limiting boundary layer friction. General friction value under the extended sliding confirm those observed in previous orbital and the related ground test studies.

  4. Vacuum pumps and systems: A review of current practice

    NASA Technical Reports Server (NTRS)

    Giles, Stuart

    1986-01-01

    A review of the fundamental characteristics of the many types of vacuum pumps and vacuum pumping systems is given. The optimum pumping range, relative cost, performance limitations, maintenance problems, system operating costs and similar subjects are discussed. Experiences from the thin film deposition, chemical processing, material handling, food processing and other industries, as well as space simulation are used to support conclusions and recommendations.

  5. Experience with Dry Running Vacuum Pumps in Helium Service

    NASA Astrophysics Data System (ADS)

    Arztmann, R.

    2008-03-01

    A process vacuum system for helium using dry running vacuum pumps only was shop tested and installed in a refrigeration plant to serve cavities operating at 2K for a cryogenic storage ring. The paper explains the joint development steps of Busch AG and Linde Kryotechnik AG to use dry running vacuum pumps for helium service at ambient temperature. A roots type booster pump followed by a non lube rotary screw pump provides very good performance in a helium vacuum pump system. Variable frequency drives on both pumps allow to adjust the pump characteristics to a wide range of operating parameters. Operation without friction of sealing elements in the compression space also of the screw pump promises extended maintenance intervals and virtually no wear on the rotors. The current plant operation at Max Plank Institute in Heidelberg, Germany Laboratory will provide additional experience for further applications.

  6. Vacuum Pump System Optimization Saves Energy at a Dairy Farm

    SciTech Connect

    2001-08-01

    In 1998, S&S Dairy optimized the vacuum pumping system at their dairy farm in Modesto, California. In an effort to reduce energy costs, S&S Dairy evaluated their vacuum pumping system to determine if efficiency gains and energy savings were possible.

  7. Methods for characterization of mechanical and electrical prosthetic vacuum pumps.

    PubMed

    Komolafe, Oluseeni; Wood, Sean; Caldwell, Ryan; Hansen, Andrew; Fatone, Stefania

    2013-01-01

    Despite increasingly widespread adoption of vacuum-assisted suspension systems in prosthetic clinical practices, there remain gaps in the body of scientific knowledge guiding clinicians' choices of existing products. In this study, we identified important pump-performance metrics and developed techniques to objectively characterize the evacuation performance of prosthetic vacuum pumps. The sensitivity of the proposed techniques was assessed by characterizing the evacuation performance of two electrical (Harmony e-Pulse [Ottobock; Duderstadt, Germany] and LimbLogic VS [Ohio Willow Wood; Mt. Sterling, Ohio]) and three mechanical (Harmony P2, Harmony HD, and Harmony P3 [Ottobock]) prosthetic pumps in bench-top testing. Five fixed volume chambers ranging from 33 cm(3) (2 in.(3)) to 197 cm(3) (12 in.(3)) were used to represent different air volume spaces between a prosthetic socket and a liner-clad residual limb. All measurements were obtained at a vacuum gauge pressure of 57.6 kPa (17 inHg). The proposed techniques demonstrated sensitivity to the different electrical and mechanical pumps and, to a lesser degree, to the different setting adjustments of each pump. The sensitivity was less pronounced for the mechanical pumps, and future improvements for testing of mechanical vacuum pumps were proposed. Overall, this study successfully offers techniques feasible as standards for assessing the evacuation performance of prosthetic vacuum pump devices.

  8. 32. VIEW LOOKING WEST SHOWING UNIT #3. VACUUM PUMP ON ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    32. VIEW LOOKING WEST SHOWING UNIT #3. VACUUM PUMP ON LEFT, CONDENSER TURBINE ON RIGHT, JET CONDENSER IN CENTER REAR - Georgetown Steam Plant, South Warsaw Street, King County Airport, Seattle, King County, WA

  9. 4. VACUUM PUMP (CONDENSATE RETURN). Hot Springs National Park, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. VACUUM PUMP (CONDENSATE RETURN). - Hot Springs National Park, Bathhouse Row, Buckstaff Bathhouse: Mechanical & Piping Systems, State Highway 7, 1 Mile North of U.S. Highway 70, Hot Springs, Garland County, AR

  10. VACUUM PUMP (CONDENSATE RETURN). Hot Springs National Park, Bathhouse ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VACUUM PUMP (CONDENSATE RETURN). - Hot Springs National Park, Bathhouse Row, Hale Bathhouse: Mechanical & Piping Systems, State Highway 7, 1 mile north of U.S. Highway 70, Hot Springs, Garland County, AR

  11. Highly sensitive vacuum ion pump current measurement system

    DOEpatents

    Hansknecht, John Christopher

    2006-02-21

    A vacuum system comprising: 1) an ion pump; 2) power supply; 3) a high voltage DC--DC converter drawing power from the power supply and powering the vacuum pump; 4) a feedback network comprising an ammeter circuit including an operational amplifier and a series of relay controlled scaling resistors of different resistance for detecting circuit feedback; 5) an optional power block section intermediate the power supply and the high voltage DC--DC converter; and 6) a microprocessor receiving feedback information from the feedback network, controlling which of the scaling resistors should be in the circuit and manipulating data from the feedback network to provide accurate vacuum measurement to an operator.

  12. Nano-materials for adhesive-free adsorbers for bakable extreme high vacuum cryopump surfaces

    SciTech Connect

    Stutzman, Marcy; Jordan, Kevin; Whitney, Roy R.

    2016-10-11

    A cryosorber panel having nanomaterials used for the cryosorption material, with nanomaterial either grown directly on the cryopanel or freestanding nanomaterials attached to the cryopanel mechanically without the use of adhesives. Such nanomaterial cryosorber materials can be used in place of conventional charcoals that are attached to cryosorber panels with special low outgassing, low temperature capable adhesives. Carbon nanotubes and other nanomaterials could serve the same purpose as conventional charcoal cryosorbers, providing a large surface area for cryosorption without the need for adhesive since the nanomaterials can be grown directly on a metallic substrate or mechanically attached. The nanomaterials would be capable of being fully baked by heating above 100.degree. C., thereby eliminating water vapor from the system, eliminating adhesives from the system, and allowing a full bake of the system to reduce hydrogen outgassing, with the goal of obtaining extreme high vacuum where the pump can produce pressures below 1.times.10.sup.-12 Torr.

  13. Better vacuum by removal of diffusion-pump-oil contaminants

    NASA Technical Reports Server (NTRS)

    Buggele, A. E.

    1975-01-01

    The complex problem of why large space simulation chambers do not realize true ultimate vacuum was investigated. Some contaminating factors affecting diffusion pump performance were identified, and some advances in vacuum distillation-fractionation technology were achieved which resulted in a two-decade-or-more lower ultimate pressure. Data are presented to show the overall or individual contaminating effects of commonly used phthalate ester plasticizers of 390 to 530 molecular weight on diffusion pump performance. Methods for removing contaminants from diffusion pump silicone oil during operation and for reclaiming contaminated oil by high-vacuum molecular distillation are described. Conceptual self-cleansing designs and operating procedures are proposed for modifying large diffusion pumps into high-efficiency distillation devices. The potential exists for application of these technological advancements to other disciplines, such as medicine, biomedical materials, metallurgy, refining, and chemical (diffusion-enrichment) processing.

  14. METHOD FOR PUMPING GASES AT LOW VACUUM PRESSURES

    DOEpatents

    Milleron, N.

    1962-06-01

    A method is given for pumping overpressure "pulses" or "bursts" of gases without a significant rise in base pressure within a "gettering-type" vacuum pump having surfaces within the pumping cavity coated with or comprising clean gettering metal, e.g., Mo or Ta. The cavity is first pumped down by any convenient means to an equilibrium base pressure in the range desired, generally below 10/sup -6/ mm Hg. At this pressure, the metal immediately adsorbs overpressures or "bursts" of gases striking same with thermal motion without raising the base pressure significantiy. Desorption takes place at an equilibrium rate which, of course, is dependent upon the equilibrium pressure, and such desorbed gases are continuously removed by diffuaion pump or other pumping, whereby said overpressures or "bursts" of gases are removed without a rise in the equilibrium pressure and/or back diffusion of the gaseous pulse from the pumping cavity. (AEC)

  15. Study on the performance prediction of screw vacuum pump

    NASA Astrophysics Data System (ADS)

    Ohbayashi, T.; Sawada, T.; Hamaguchi, M.; Miyamura, H.

    2001-01-01

    Pumping characteristics of the screw vacuum pump were investigated. The aim of this study was to establish a method of the performance prediction and a way to design the pump that satisfies specific requirements. The performance was analysed by the balance among geometrical pumping speed, net throughput and leaks. The leaks flow through clearances between a screw rotor and a stator, and clearances between two meshing rotors. These leaks were estimated with the results based on the linearised BGK model and the flows through ideal labyrinthes. Experiments were carried out by rotors of 120 mm diameter, and pumping speed and ultimate pressure were measured. The comparison between the measurements and the predicted values shows that the present method predicts the performance of the screw pump with a sufficient accuracy for practical applications.

  16. High vacuum portable pumping station suitable for accelerator use

    SciTech Connect

    Stattel, P.; Briggs, J.; DeBoer, W.; Skelton, R.

    1985-01-01

    The need for a Portable Pump Station for Ultra High Vacuum use became apparent when the ''Isabelle'' collider was first being designed. A Portable Pump Station had to be developed which contained the following features: maneuverability, compact size, rugged, self protected against various failures, capable of running unattended, and capable of reaching 10/sup -9/ torr. The Pump Station that was developed and other variations are the subject of this paper. Emphasis will be on the Isabelle and HITL versions. 1 ref., 2 figs., 1 tab.

  17. Ultra-high speed vacuum pump system with first stage turbofan and second stage turbomolecular pump

    SciTech Connect

    Jostlein, Hans

    2006-04-04

    An ultra-high speed vacuum pump evacuation system includes a first stage ultra-high speed turbofan and a second stage conventional turbomolecular pump. The turbofan is either connected in series to a chamber to be evacuated, or is optionally disposed entirely within the chamber. The turbofan employs large diameter rotor blades operating at high linear blade velocity to impart an ultra-high pumping speed to a fluid. The second stage turbomolecular pump is fluidly connected downstream from the first stage turbofan. In operation, the first stage turbofan operates in a pre-existing vacuum, with the fluid asserting only small axial forces upon the rotor blades. The turbofan imparts a velocity to fluid particles towards an outlet at a high volume rate, but moderate compression ratio. The second stage conventional turbomolecular pump then compresses the fluid to pressures for evacuation by a roughing pump.

  18. Evaluation of a Prototype Hybrid Vacuum Pump to Provide Vacuum-Assisted Suspension for Above-Knee Prostheses

    PubMed Central

    Major, Matthew J.; Caldwell, Ryan; Fatone, Stefania

    2015-01-01

    Vacuum-assisted suspension (VAS) of prosthetic sockets utilizes a pump to evacuate air from between the prosthetic liner and socket, and are available as mechanical or electric systems. This technical note describes a hybrid pump that benefits from the advantages of mechanical and electric systems, and evaluates a prototype as proof-of-concept. Cyclical bench testing of the hybrid pump mechanical system was performed using a materials testing system to assess the relationship between compression cycles and vacuum pressure. Phase 1 in vivo testing of the hybrid pump was performed by an able-bodied individual using prosthesis simulator boots walking on a treadmill, and phase 2 involved an above-knee prosthesis user walking with the hybrid pump and a commercial electric pump for comparison. Bench testing of 300 compression cycles produced a maximum vacuum of 24 in-Hg. In vivo testing demonstrated that the hybrid pump continued to pull vacuum during walking, and as opposed to the commercial electric pump, did not require reactivation of the electric system during phase 2 testing. The novelty of the hybrid pump is that while the electric system provides rapid, initial vacuum suspension, the mechanical system provides continuous air evacuation while walking to maintain suspension without reactivation of the electric system, thereby allowing battery power to be reserved for monitoring vacuum levels. PMID:27462383

  19. Evaluation of a Prototype Hybrid Vacuum Pump to Provide Vacuum-Assisted Suspension for Above-Knee Prostheses.

    PubMed

    Major, Matthew J; Caldwell, Ryan; Fatone, Stefania

    2015-12-01

    Vacuum-assisted suspension (VAS) of prosthetic sockets utilizes a pump to evacuate air from between the prosthetic liner and socket, and are available as mechanical or electric systems. This technical note describes a hybrid pump that benefits from the advantages of mechanical and electric systems, and evaluates a prototype as proof-of-concept. Cyclical bench testing of the hybrid pump mechanical system was performed using a materials testing system to assess the relationship between compression cycles and vacuum pressure. Phase 1 in vivo testing of the hybrid pump was performed by an able-bodied individual using prosthesis simulator boots walking on a treadmill, and phase 2 involved an above-knee prosthesis user walking with the hybrid pump and a commercial electric pump for comparison. Bench testing of 300 compression cycles produced a maximum vacuum of 24 in-Hg. In vivo testing demonstrated that the hybrid pump continued to pull vacuum during walking, and as opposed to the commercial electric pump, did not require reactivation of the electric system during phase 2 testing. The novelty of the hybrid pump is that while the electric system provides rapid, initial vacuum suspension, the mechanical system provides continuous air evacuation while walking to maintain suspension without reactivation of the electric system, thereby allowing battery power to be reserved for monitoring vacuum levels.

  20. Tritium contamination and decontamination of sealing oil for vacuum pump

    SciTech Connect

    Takeishi, T.; Kotoh, K.; Kawabata, Y.; Tanaka, J.I.; Kawamura, S.; Iwata, M.

    2015-03-15

    The existence of tritium-contaminated oils from vacuum pumps used in tritium facilities, is becoming an important issue since there is no disposal way for tritiated waste oils. On recovery of tritiated water vapor in gas streams, it is well-known that the isotope exchange reaction between the gas phase and the liquid phase occurs effectively at room temperature. We have carried out experiments using bubbles to examine the tritium contamination and decontamination of a volume of rotary-vacuum-pump oil. The contamination of the pump oil was made by bubbling tritiated water vapor and tritiated hydrogen gas into the oil. Subsequently the decontamination was processed by bubbling pure water vapor and dry argon gas into the tritiated oil. Results show that the water vapor bubbling was more effective than dry argon gas. The experiment also shows that the water vapor bubbling in an oil bottle can remove and transfer tritium efficiently from the tritiated oil into another water-bubbling bottle.

  1. Large area, surface discharge pumped, vacuum ultraviolet light source

    DOEpatents

    Sze, Robert C.; Quigley, Gerard P.

    1996-01-01

    Large area, surface discharge pumped, vacuum ultraviolet (VUV) light source. A contamination-free VUV light source having a 225 cm.sup.2 emission area in the 240-340 nm region of the electromagnetic spectrum with an average output power in this band of about 2 J/cm.sup.2 at a wall-plug efficiency of approximately 5% is described. Only ceramics and metal parts are employed in this surface discharge source. Because of the contamination-free, high photon energy and flux, and short pulse characteristics of the source, it is suitable for semiconductor and flat panel display material processing.

  2. Large area, surface discharge pumped, vacuum ultraviolet light source

    DOEpatents

    Sze, R.C.; Quigley, G.P.

    1996-12-17

    Large area, surface discharge pumped, vacuum ultraviolet (VUV) light source is disclosed. A contamination-free VUV light source having a 225 cm{sup 2} emission area in the 240-340 nm region of the electromagnetic spectrum with an average output power in this band of about 2 J/cm{sup 2} at a wall-plug efficiency of approximately 5% is described. Only ceramics and metal parts are employed in this surface discharge source. Because of the contamination-free, high photon energy and flux, and short pulse characteristics of the source, it is suitable for semiconductor and flat panel display material processing. 3 figs.

  3. Fusion reactor high vacuum pumping: Charcoal cryosorber tritium exposure results

    SciTech Connect

    Sedgley, D.W.; Walthers, C.R.; Jenkins, E.M. )

    1991-01-01

    Recent experiments, have shown the practically of using activated charcoal (coconut charcoal) at 4{degrees}K to pump helium and hydrogen isotopes for a fusion reactor. Both speed and capacity for deuterium/helium and tritium/helium-3 mixtures were shown to be satisfactory. The long term effects of tritium on the charcoal/cement system developed by Grumman and LLNL were not known and a program was undertaken to see what, if any, effect long term tritium exposure has on the cryosorber. Several charcoal on aluminum test samples were subjected to six months exposure of tritium at approximately 77{degrees}K. The tritium was scanned several times with a residual gas analyzer and the speed-capacity performance of the samples was measured before, approximately half way through and after the exposure. Modest effects were noted which would not seriously restrict charcoal's use as a cryosorber for fusion reactor high vacuum pumping applications. 4 refs., 8 figs.

  4. Pressure distribution along the AGS vacuum chambers with new types of pump out conduits

    SciTech Connect

    Nayak, S.; Mapes, M.; Smart, L.; Weiss, D.

    2015-10-28

    The AGS HEBT and ring vacuum system is monitored by the discharge current of the magnet ion pumps, which is proportional to the pressure at the inlet port of these ion pumps. The discharge current is measured and suitably calibrated to indicate the ion pump pressure. In order to calculate the vacuum chamber pressure from the ion pump pressure, a detailed analysis is essential to compute their difference in different scenarios. Such analysis has been carried out numerically in the past for the system with the older type of pump out conduits, and similar analysis using FEM in ANSYS is presented in this paper with the newer type of pump out conduit.

  5. A large high vacuum, high pumping speed space simulation chamber for electric propulsion

    NASA Technical Reports Server (NTRS)

    Grisnik, Stanley P.; Parkes, James E.

    1994-01-01

    Testing high power electric propulsion devices poses unique requirements on space simulation facilities. Very high pumping speeds are required to maintain high vacuum levels while handling large volumes of exhaust products. These pumping speeds are significantly higher than those available in most existing vacuum facilities. There is also a requirement for relatively large vacuum chamber dimensions to minimize facility wall/thruster plume interactions and to accommodate far field plume diagnostic measurements. A 4.57 m (15 ft) diameter by 19.2 m (63 ft) long vacuum chamber at NASA Lewis Research Center is described. The chamber utilizes oil diffusion pumps in combination with cryopanels to achieve high vacuum pumping speeds at high vacuum levels. The facility is computer controlled for all phases of operation from start-up, through testing, to shutdown. The computer control system increases the utilization of the facility and reduces the manpower requirements needed for facility operations.

  6. The effect of vacuum pump oil on the chemotactic behavior of soil bacteria

    SciTech Connect

    Dunifon, R.E.; Hazen, T.C.

    1990-01-01

    The use of biodegradation in the cleanup and transformation of waste materials is an economical and environmentally safe practice. Using chemotaxis, or the movement of bacteria toward or away from compounds, in biodegradation is an area that is being studied at the Savannah River Laboratory. This study investigates the inhibition of vacuum pump oil on the chemotaxis of soil bacteria. It was found that vacuum pump oil does have an inhibitory effect on the movement of bacteria. This inhibition will have to be considered when studying the possibility of using chemotaxis to degrade vacuum pump oil, or any other petroleum products. 5 refs., 5 figs.

  7. Design Document for Control Dewar and Vacuum Pump Platforms

    SciTech Connect

    Rucinksi, R.; /Fermilab

    1997-08-27

    This engineering note documents the design of the control dewar and vacuum pump platform that is to be installed on the D-Zero detector. It's purpose is twofold. Firstly it is a summary and repository of the final design calculations of the structure. Secondly, it documents that design follows the American Institute of Steel Construction (AISC) manual and applicable OSHA requirements with respect to walking working surfaces. The information contained in the main body of this note is supported by raw calculations included as the appendix. The platform is a truss type frame strucrure constructed primarily of rectangular steel tubing. The upper platform is for support of the control dewar (cryogenic/electrical interface for the solenoid), visible light photon counter (VLPC) cryogenic bayonet can, and infrequently, personnel during the connection and disconnection of the detector to building services. Figure 1 shows a layout of the structure as mounted on the detector and with the installed equipment. The connection of the platform to the detector is not conventional. Two main booms cantilever the structure to a location outside of the detector. The mounting location and support booms allow for the uninhibited motion of the detector components.

  8. Vacuum hand pump apparatus for collecting water samples from a horizontal intragravel pipe

    USGS Publications Warehouse

    Saiki, Michael K.; Martin, Barbara A.

    1996-01-01

    We describe a lightweight, portable vacuum hand pump apparatus for use in collecting water samples from horizontal intragravel pipe samplers buried in the stream bottom. The apparatus is easily fabricated from relatively inexpensive materials available at many laboratory supply houses.

  9. Under Pressure: Activities with a Vacuum Pump (and Some Marshmallows) Help Students Learn about Pressure.

    ERIC Educational Resources Information Center

    Galus, Pamela

    2002-01-01

    Introduces a science demonstration that illustrates the effects of pressure and gravity on humans using a marshmallow man and a vacuum pump. Demonstrates the same concept with shaving cream, balloons, and boiling water without raising temperature. (YDS)

  10. D0 Solenoid Upgrade Project: Vacuum Pumping Calculations for the D0 Solenoid

    SciTech Connect

    Rucinski, R.; /Fermilab

    1993-08-02

    This engineering note documents the calculations done to determine the vacuum pumping speed for the D-Zero solenoid. The raw calculations are attached. A summary of the results are listed. The vacuum pumping speed of the solenoid is determined by the conductance of the pumping path. At higher pressure ranges during initial pumpdown, the conductances will be rather high. Calculations were not done for the transient pumpdown period, only the steady state type pumping situation. The pressure is assumed to be on the order of 10E-7 torr. This is the free molecular flow regime based on Knudsen number. This pressure regime is also where the pumping speed would be least. The conductances were calculated based on pumping helium gas at a temperature of 300 Kelvin. The total conductance of the pumping path from the solenoid to the inlet of the turbomolecular pump is 11.8 L/s. The effective pumping speed of a 1000 L/s turbo pump attached to this pumping path is 11.7 L/s. The minimum required pumping speed for design purposes was set at 4.3 L/s. This value was arrived at by assuming a warm leak size (10E-8 atm-cc/sec) was not detected during fabrication of the solenoid. It is then assumed that the leak leaks cold liquid helium into the vacuum space. With this leak rate, a 4.3 L/s pumping speed would be able to maintain a 2 x 10E-7 torr pressure in the solenoid vacuum jacket. The solenoid would be able to be operated with this small leak with continuous pumping.

  11. The MEMS Knudsen Compressor as a Vacuum Pump for Space Exploration Applications

    NASA Technical Reports Server (NTRS)

    Vargo, S. E.; Muntz, E. P.; Tang, W. C.

    2000-01-01

    Several lander, probe and rover missions currently under study at the Jet Propulsion Laboratory (JPL) and especially in the Microdevices Laboratory (MDL) Center for Space Microelectronics Technology, focus on utilizing microelectromechanical systems (MEMS) based instruments for science data gathering. These small instruments and NASA's commitment to "faster, better, cheaper" type missions has brought about the need for novel approaches to satisfying mission requirements. Existing in-situ instrument systems clearly lack novel and integrated methods for satisfying their vacuum needs. One attractive candidate for a MEMS vacuum pump is the Knudsen Compressor, which operates based on thermal transpiration. Thermal transpiration describes gas flows induced by temperature differences maintained across orifices, porous membranes or capillary tubes under rarefied conditions. This device has two overwhelmingly attractive features as a MEMS vacuum pump - no moving parts and no fluids. An initial estimate of a Knudsen Compressor's pumping power requirements for a surface atmospheric sampling task on Mars is less than 80 mW, significantly below than alternative pumps. Due to the relatively low energy use for this task and the applicability of the Knudsen Compressor to other applications, the development of a Knudsen Compressor utilizing MEMS fabrication techniques has been initiated. This paper discusses the initial fabrication of a single-stage MEMS Knudsen Compressor vacuum pump, provides performance criteria such as pumping speed, size, energy use and ultimate pressure and details vacuum pump applications in several MDL related in-situ instruments.

  12. Elmo Bumpy Torus proof of principle, Phase II: Title 1 report. Volume V. Vacuum-pumping system. Preliminary design report

    SciTech Connect

    Not Available

    1982-02-26

    This report summarizes Title I Preliminary Design of the EBT-P Vacuum Pumping System. The Vacuum Pumping System has been designed by the McDonnell Douglas Astronautics Co. - St. Louis (MDAC). It includes the necessary vacuum pumps and vacuum valves to evacuate the torus, the Mirror Coil Dewars (MC Dewars), and the Gyrotron Magnet Dewars. The pumping ducts, manifolds, and microwave protection system are also included. A summary of the function of each subsystem and a description of its principle components is provided below. The analyses performed during the system design are also identified.

  13. Performance tests of vacuum pumps in small and large dental facilities.

    PubMed

    Moutsoglou, A; Weng, Y; Han, Y

    2000-01-01

    A study was conducted to compare and assess the performance of various vacuum pumps in small and large dental clinic operations. A four-chair dental clinic operation was set up at the laboratory to simulate a small dental clinic environment. The performance of two dry and two wet pumps was assessed in the laboratory via extensive performance data acquisition tests. Data were also collected in two small dental clinics of practising dentists. Large dental system performance tests were conducted at the Ellsworth Air Force Base and Minot Air Force Base dental clinics. At each clinic, data were collected with both the existent turbine pump and a rotary vane RAMVAC pump.

  14. Ejector/liquid ring pump provides <0. 30 mm Hg vacuum for polymerization vessel

    SciTech Connect

    Lockwood, A.; Gaines, A.

    1982-03-01

    Firestone Fibers and Textiles Company, a division of Firestone Tire and Rubber Company, manufactures tire and industrial yarns of polyester and nylon-6. Nylon-6 molding and extrusion resins are also produced at the plant in Hopewell, Virginia. The process for making polyester requires an extremely low vacuum on the polymerization reactor. A consistent polymerization vessel vacuum of 0.3 mm Hg is needed, but the existing vacuum source, a five-stage steam jet ejector, could only provide a 0.5 mm Hg level. Two options were considered when the company decided to replace the original system with a system designed for 0.15 mm Hg with a non-condensible gas load of 10.8 lb/hr. A new five-stage jet ejector system to meet these requirements would use 1395 lb/hr of 100 psig steam. The other option was a hybrid vacuum source composed of a three-stage steam ejector system and a liquid ring vacuum pump that is more energy efficient than ejectors for low vacuum applications. The hybrid system was selected because the three-stage jet ejector would use only 1240 lb/hr of 100 psig steam. The liquid ring vacuum pump would increase the material and installation cost of the system by about $4000, but the savings in steam consumption would pay back the added cost in less than two years. The jet ejector/liquid ring vacuum pump system has provided both the capacity and the extremely low vacuum needed for the polyester polymerization vessel, after making a small modification. The hybrid vacuum source is reliable, requires only routine maintenance, and will contiue to save substantial amounts of steam each year compared to the five-stage steam jet ejector.

  15. Pump-probe photoelectron spectroscopy by a high-power 90 nm vacuum-ultraviolet laser

    NASA Astrophysics Data System (ADS)

    Sato, Motoki; Suzuki, Yoshi-ichi; Suzuki, Toshinori; Adachi, Shunsuke

    2016-02-01

    We present pump-probe photoelectron spectroscopy of Kr and NO using a high-power vacuum-ultraviolet (VUV) laser at a wavelength of 90 nm. Clear quantum beats are observed in the photoelectron angular distributions as well as in the photoelectron yields, resulting from the coherent excitation of two Kr Rydberg states by the VUV pump. The entire Franck-Condon envelope of the NO A(2Σ+) excited state is also successfully captured by the VUV probe.

  16. Triggering vacuum capillaries for pneumatic pumping and metering liquids in point-of-care immunoassays.

    PubMed

    Weng, Kuo-Yao; Chou, Nien-Jen; Cheng, Jya-Wei

    2008-07-01

    An innovative vacuum capillary pneumatic actuation concept that can be used for point-of-care testing has been investigated. The vacuum glass capillaries are encapsulated within a laminated pouch and incorporated into the fluidic card. Vacuum glass capillaries broken by external force such as finger pressure, generate the pneumatic forces to induce liquid flow in the fluidic system. The sizes of vacuum capillary play a vital role in the pumping and metering functions of the system. The luteinizing hormone (LH) chromatographic immunoassay performances in the fluidic cards show consistency comparable to that obtained by manual micropipetting. The vacuum capillary pneumatic actuation will be applied in other complex handling step bioassays and lab-on-a-chip devices.

  17. PNEUMATIC PUMP TEST FOR DESIGN OF SOIL VACUUM EXTRACTION

    EPA Science Inventory

    In-situ pneumatic pumping tests were performed to estimate the pneumatic permeability at a site containing soils contaminated with aviation gasoline. Determination of pneumatic permeability was necessary to evaluate soil-air discharge or pore volume exchange rates. Pressure propa...

  18. Investigation of a quadrupole ultra-high vacuum ion pump

    NASA Technical Reports Server (NTRS)

    Schwarz, H. J.

    1974-01-01

    The new nonmagnetic ion pump resembles the quadrupole ionization gage. The dimensions are larger, and hyperbolically shaped electrodes replace the four rods. Their surfaces follow y sq. = 36 + x sq. (x, y in centimeters). The electrodes, 55 cm long, are positioned lengthwise in a tube. At one end a cathode emits electrons; at the other end a narrowly wound flat spiral of tungsten clad with titanium on cathode potential can be heated for titanium evaporation. Electrons accelerated by a dc potential of the surface electrodes oscillate between the ends on rotational trajectories, if a high frequency potential superimposed on the dc potential is properly adjusted. Pumping speeds (4-100 liter/sec) for different gases at different peak voltages (1000-3000V) at corresponding frequencies (57-100 MHz), and at different pressures 0.00001 to the minus 9 power Torr were observed. The lowest pressure reached was below 10 to the minus 10 power Torr.

  19. Study on Design of Rotor Profile for the Twin Screw Vacuum Pump with Single Thread Tooth

    NASA Astrophysics Data System (ADS)

    Lu, Y.; Guo, B.; Geng, M. F.

    2015-08-01

    The trapezoidal profile is always used as part of tooth profile in the screw vacuum pump. However, interferential phenomenon occurs when using trapezoidal tooth profile. The arc is added to the trapezoidal profile to obtain the self-conjugate curve. The geometric characters of new profiles are compared with the old ones from view point of area of leakage triangle, length of contacting line, area utility coefficient, and etc. The rotor with the selfconjugate curve has characteristics of the small axial leakage area. Radial leakage from the carryover was within the same volume and would not influence the mass flow rate of the vacuum pump. High ultimate vacuum can be reached by utilizing this profile.

  20. Calculation methodology of the heat pump in the process of oscillating vacuum-conductive drying of lumber

    NASA Astrophysics Data System (ADS)

    Safin, R. R.; Khasanshin, R. R.; Shaikhutdinova, A. R.; Khakimzyanov, I. F.

    2016-04-01

    The oscillating technologies consisting in alternating of the stage of heating of the material and vacuumization are the most advanced in the process of wood drying. In this regard, the article examines the energy-saving technology of the oscillating vacuum-conductive drying of lumber, during which the thermal energy of the moisture evaporated from the material under vacuum in one chamber by using the heat pump is transferred to the heating of the material in the other chamber. The authors develop the method of calculating the rate of removal of moisture from the heated material at the stage of vacuumization depending on the depth of vacuum, temperature, humidity and thickness of the material, which is the initial condition for calculating the heat pump.

  1. Thin layer modeling of tom yum herbs in vacuum heat pump dryer.

    PubMed

    Artnaseaw, A; Theerakulpisut, S; Benjapiyaporn, C

    2010-04-01

    Thin layer vacuum heat pump drying experiments were conducted to determine drying models for Tom Yum herbs (chili, lemon grass, kaffir lime leaf and galangal slice). The drying experiments were conducted in a vacuum heat pump dryer at a constant drying pressure of 0.2 bars and drying temperatures ranging from 50 °C to 65 °C. The experimental results were fitted to a number of well-known thin layer drying models and it was found, for the range of drying temperature tested, that the Midilli model is the best model for all Tom Yum herbs. To account for the influence of drying temperature, the constants and coefficients of model were formulated as functions of the drying temperature. Statistical tests of agreement between the model and experimental results were performed by determining the coefficient of determination (R²) , reduced chi-square (χ²) and root mean square error (RMSE). It was found that the model is in very good agreement with the experimental results.

  2. Efficacy and safety of active silicone oil removal through a 23-gauge transconjunctival cannula using an external vacuum pump

    PubMed Central

    Oh, Hyun Ju; Chang, Woohyok; Sagong, Min

    2015-01-01

    AIM To evaluate the efficacy and safety of active removal of silicone oil with low and high viscosity through a 23-gauge transconjunctival cannula using an external vacuum pump. METHODS This study was conducted as a prospective, interventional case series. A total of 22 eyes of 21 patients [1000 centistokes (cSt): 17 eyes, 5700 cSt: 5 eyes] were included in this study. All patients underwent active silicone oil removal via the entire lumen of a 23-gauge microcannula with suction pressure of a 650-700 mm Hg vacuum using an external vacuum pump. A tubing adaptor from the Total Plus Pak® (Alcon, Fort Worth, USA) was used to join the microcannula and silicone vacuum tube connected to an external vacuum pump. Main outcome measures were mean removal time, changes of intraocular pressure (IOP) and visual acuity, and intraoperative and postoperative complications. RESULTS Mean removal time (min) was 1.49±0.43 for 1000 cSt and 7.12±1.27 for 5700 cSt. The IOP was 18.57±7.48 mm Hg at baseline, 11.68±4.55 mm Hg at day 1 postoperatively (P<0.001), and 15.95±4.92, 16.82±3.81, 17.41±3.50, and 17.09±3.01 mm Hg after one week, one month, three months, and six months, respectively. All patients showed improved or stabilized visual acuity. There was no occurrence of intraoperative or postoperative complications during the follow up period. CONCLUSION This technique for active removal of silicone oil through a 23-gauge cannula using an external vacuum pump is fast, effective, and safe as well as economical for silicone oil with both low and high viscosity in all eyes with pseudophakia, aphakia, or phakia. PMID:25938054

  3. Vacuum chamber with distributed titanium sublimation pumping for the G-line wiggler at Cornell High Energy Synchrotron Source

    NASA Astrophysics Data System (ADS)

    Li, Y.; He, Y.; Mistry, N. B.

    2003-07-01

    This article describes a 3-m-long vacuum chamber for the new wiggler magnet at the Cornell Electron Storage Ring (CESR) for the synchrotron light beam line of the Cornell High Energy Synchrotron Source (CHESS). Copper was chosen as the main chamber material for its good electric and thermal conductivities. Proper mechanical design and welding procedure were implemented to meet very tight tolerances to ensure adequate vertical aperture for the stored beams in CESR while allowing the required small wiggler gap. Distributed titanium sublimation pumping is incorporated along the 3 m length of the chamber to provide sufficient pumping speed and capacity for CESR and CHESS operations. The chamber pumping performance was evaluated prior to installation. Linear distributed pumping speeds at the beam line of ~720 l/s/m for N2 and CO and ~4000 l/s/m for H2 were measured. The measured pumping capacities for N2, CO and H2 are ~1.0, ~2.0 and ~77 Torr l, respectively, for each titanium sublimation cycle. Measurements also showed that CO molecules adsorb on the N2 and H2 saturated titanium films with virtually the same initial sticking coefficient as on a fresh titanium film. Analyses indicated very different CO adsorption mechanisms between the N2 and H2 saturated titanium films. While the replacement of surface H2 by CO was observed, little desorption of nitrogen was measured. Operational experience showed excellent vacuum pumping performance over two years after the chamber installation.

  4. An electrostatic ion pump with nanostructured Si field emission electron source and Ti particle collectors for supporting an ultra-high vacuum in miniaturized atom interferometry systems

    NASA Astrophysics Data System (ADS)

    Basu, Anirban; Velásquez-García, Luis F.

    2016-12-01

    We report a field emission-based, magnetic-less ion pump architecture for helping maintain a high vacuum within a small chamber that is compatible with miniaturized cold-atom interferometry systems. A nanostructured silicon field emitter array, with each nano-sharp tip surrounded by a self-aligned proximal gate electrode, is used to generate a surplus of electrons that cause impact ionization of gas molecules. A two-stage cylindrical electron collector, made of titanium, is used to increase the travel distance of the electrons, augmenting the ionization probability; gas ionization is subsequently followed by gettering of the ions by a negatively charged, annular-shaped titanium electrode. A proof-of-concept pump prototype was characterized using a 25 cm3 stainless steel vacuum chamber backed up by an external turbomolecular pump, a diaphragm pump, and a standard ion pump. Pumping action was observed with the electrostatic pump operating alone after an initial rapid rise of the chamber pressure due to electron/ion scrubbing. In addition, running the electrostatic pump in combination with the standard ion pump results in a lower vacuum level compared to the vacuum level produced by the standard ion pump acting alone. A proposed reduced-order model accurately predicts the functional dependence of the pressure versus time data and provides a good estimate of the characteristic pumping time constant inferred from the experiments.

  5. Theoretical investigation of isotope exchange reaction in tritium-contaminated mineral oil in vacuum pump.

    PubMed

    Dong, Liang; Xie, Yun; Du, Liang; Li, Weiyi; Tan, Zhaoyi

    2015-04-28

    The mechanism of the isotope exchange reaction between molecular tritium and several typical organic molecules in vacuum pump mineral oil has been investigated by density functional theory (DFT), and the reaction rates are determined by conventional transition state theory (TST). The tritium-hydrogen isotope exchange reaction can proceed with two different mechanisms, the direct T-H exchange mechanism and the hyrogenation-dehydrogenation exchange mechanism. In the direct exchange mechanism, the titrated product is obtained through one-step via a four-membered ring hydrogen migration transition state. In the hyrogenation-dehydrogenation exchange mechanism, the T-H exchange could be accomplished by the hydrogenation of the unsaturated bond with tritium followed by the dehydrogenation of HT. Isotope exchange between hydrogen and tritium is selective, and oil containing molecules with OH and COOH groups can more easily exchange hydrogen for tritium. For aldehydes and ketones, the ability of T-H isotope exchange can be determined by the hydrogenation of T2 or the dehydrogenation of HT. The molecules containing one type of hydrogen provide a single product, while the molecules containing different types of hydrogens provide competitive products. The rate constants are presented to quantitatively estimate the selectivity of the products.

  6. Ultra high vacuum pumping system and high sensitivity helium leak detector

    DOEpatents

    Myneni, G.R.

    1997-12-30

    An improved helium leak detection method and apparatus are disclosed which increase the leak detection sensitivity to 10{sup {minus}13} atm cc/s. The leak detection sensitivity is improved over conventional leak detectors by completely eliminating the use of o-rings, equipping the system with oil-free pumping systems, and by introducing measured flows of nitrogen at the entrances of both the turbo pump and backing pump to keep the system free of helium background. The addition of dry nitrogen flows to the system reduces back streaming of atmospheric helium through the pumping system as a result of the limited compression ratios of the pumps for helium. 2 figs.

  7. Ultra high vacuum pumping system and high sensitivity helium leak detector

    DOEpatents

    Myneni, Ganapati Rao

    1997-01-01

    An improved helium leak detection method and apparatus are disclosed which increase the leak detection sensitivity to 10.sup.-13 atm cc s.sup.-1. The leak detection sensitivity is improved over conventional leak detectors by completely eliminating the use of o-rings, equipping the system with oil-free pumping systems, and by introducing measured flows of nitrogen at the entrances of both the turbo pump and backing pump to keep the system free of helium background. The addition of dry nitrogen flows to the system reduces backstreaming of atmospheric helium through the pumping system as a result of the limited compression ratios of the pumps for helium.

  8. Mass spectrometer with magnetic pole pieces providing the magnetic fields for both the magnetic sector and an ion-type vacuum pump

    NASA Technical Reports Server (NTRS)

    Sieradski, L. M.; Giffin, C. E.; Nier, A. O. (Inventor)

    1976-01-01

    A mass spectrometer (MS) with unique magnetic pole pieces which provide a homogenous magnetic field across the gap of the MS magnetic sector as well as the magnetic field across an ion-type vacuum pump is disclosed. The pole pieces form the top and bottom sides of a housing. The housing is positioned so that portions of the pole pieces form part of the magnetic sector with the space between them defining the gap region of the magnetic sector, through which an ion beam passes. The pole pieces extend beyond the magnetic sector with the space between them being large enough to accommodate the electrical parts of an ion-type vacuum pump. The pole pieces which provide the magnetic field for the pump, together with the housing form the vacuum pump enclosure or housing.

  9. Miniature ion-sorption vacuum pump with CNT field-emission electron source

    NASA Astrophysics Data System (ADS)

    Grzebyk, T.; Górecka-Drzazga, A.

    2013-01-01

    Generation and maintenance of the high vacuum in the MEMS-type (micro-electro-mechanical system) microsystems and vacuum nanoelectronics devices remain a major problem today. The phenomena of gas desorption from the surface of a microcavity and outgassing of materials limit the vacuum to the level of about 10-1 Pa. In this paper, a new MEMS-type micropump for generating a high vacuum in a microcavity is presented. The main component of the ion-sorption micropump is a carbon nanotube (CNT) field-emission electron source. Test structures of the electron source with electrophoretically deposited CNT have been fabricated and measured. A satisfactory value of the emission current and a low turn-on voltage have been obtained. The elaborated electron source has been applied to the micropump structure; it has enabled us to achieve a vacuum level below 10-3 Pa.

  10. Calculation of the characteristics of the rotor of a turbomolecular vacuum pump

    SciTech Connect

    Pereslavtsev, A.V.

    1987-02-01

    This paper constructs computational procedures for the molecular gas dynamics and computer-aided design of a turbomolecular pump to be used for the pumping of hydrogen and its isotopes in thermonuclear devices. The rotor design computations are based on the molecular-kinetic theory of gases and utilize the Monte Carlo method in a three-dimensional flow model.

  11. Vacuum: From Art to Exact Science.

    ERIC Educational Resources Information Center

    Lafferty, James M.

    1981-01-01

    Reviews the history of vacuum technology. Includes vacuum pump developments (mechanical, ion, and cyrogenic pumps), measurement techniques, the development of the American Vacuum Society, and electronics in vacuum technology. (JN)

  12. Wide Range Vacuum Pumps for the SAM Instrument on the MSL Curiosity Rover

    NASA Technical Reports Server (NTRS)

    Sorensen, Paul; Kline-Schoder, Robert; Farley, Rodger

    2014-01-01

    Creare Incorporated and NASA Goddard Space Flight Center developed and space qualified two wide range pumps (WRPs) that were included in the Sample Analysis at Mars (SAM) instrument. This instrument was subsequently integrated into the Mars Science Laboratory (MSL) "Curiosity Rover," launched aboard an Atlas V rocket in 2011, and landed on August 6, 2012, in the Gale Crater on Mars. The pumps have now operated for more than 18 months in the Gale Crater and have been evacuating the key components of the SAM instrument: a quadrupole mass spectrometer, a tunable laser spectrometer, and six gas chromatograph columns. In this paper, we describe the main design challenges and the ways in which they were solved. This includes the custom design of a miniaturized, high-speed motor to drive the turbo drag pump rotor, analysis of rotor dynamics for super critical operation, and bearing/lubricant design/selection.

  13. Elimination of the Vacuum Pump Requirement for High-Resolution Rotational Spectroscopy.

    NASA Astrophysics Data System (ADS)

    Holt, Jennifer; Daly, Ryan W.; Neese, Christopher F.; De Lucia, Frank C.

    2015-06-01

    It has been observed that with the advances being driven by the wireless communications industry, the microwave components for submillimeter wave spectrometers and sensors will become almost "free". Moreover, these electronic components will require little power. However, neither of these attributes applies to the vacuum requirements for high-resolution rotational spectroscopy. We will report on the design, construction, and operation of a simple spectroscopic cell that overcomes these problems.

  14. DSMC Modeling of the Differentially Pumped Magnum-PSI Vacuum System

    SciTech Connect

    Eck, H. J. N. van; Goedheer, W. J.; Koppers, W. R.; Kleyn, A. W.; Cardozo, N. J. Lopes

    2008-12-31

    The FOM Institute for Plasma Physics Rijnhuizen (FOM = Foundation for Fundamental Research on Matter) has started a new line of research to study the interaction of intense plasma fluxes with a material surface. An important experimental tool for this programme will be the Magnum-PSI high-flux linear plasma generator operating in the ITER-relevant regime of plasma surface interaction (PSI). ITER is the next step in fusion reactor research (ITER is Latin for 'the way'). In Magnum-PSI a plasma beam is guided from the source to a target by a strong axial magnetic field. Besides ionized particles, the plasma source produces hot neutral gas which has to be prevented from reaching the target region. In this paper it is investigated to what extent a differential pumping scheme can prevent the influx of neutral gas from the source in the target region. The results of neutral gas simulations using the Direct Simulation Monte Carlo (DSMC) method will be discussed. We will focus on the supersonic expansion as a function of background pressure and determine the influence of the skimmers on the expansion. We will demonstrate that differential pumping can be used in Magnum-PSI to reach low enough pressures in the target region. Finally, we give the optimum position of the skimmer.

  15. A differentially pumped secondary electron detector for low-vacuum scanning electron microscopy.

    PubMed

    Jacka, M; Zadrazil, M; Lopour, F

    2003-01-01

    A new design of secondary electron (SE) detector is described for use in low-vacuum scanning electron microscopes. Its distinguishing feature is a separate detector chamber, which can be maintained at a pressure independent of the pressure in the specimen chamber. The two chambers are separated by a perforated membrane or mesh across which an electric field is applied, making it relatively transparent to low-energy electrons but considerably less so to the gas molecules. The benefits of this arrangement are discussed. The final means of detecting the electrons can be a conventional scintillator and photomultiplier arrangement or any of the methods using the ambient gas as an amplifying medium. Images obtained with the detector show good SE contrast and low backscattered electron contribution.

  16. Pump

    SciTech Connect

    Johnson, J.W.; Abdul.Hye, A.B.M.

    1983-10-25

    A pump for injecting chemicals into a well employs a pivot arm for synchronous movement with a well pump. The pivot arm causes reciprocation of a plunger within the body of the chemical pump. The plunger, during its upward stroke causes the entry of chemicals from an outside source into the pump body and, during its downward stroke, causes the exiting of the chemicals into the well. (2 claims.

  17. Vacuum Technology

    SciTech Connect

    Biltoft, P J

    2004-10-15

    The environmental condition called vacuum is created any time the pressure of a gas is reduced compared to atmospheric pressure. On earth we typically create a vacuum by connecting a pump capable of moving gas to a relatively leak free vessel. Through operation of the gas pump the number of gas molecules per unit volume is decreased within the vessel. As soon as one creates a vacuum natural forces (in this case entropy) work to restore equilibrium pressure; the practical effect of this is that gas molecules attempt to enter the evacuated space by any means possible. It is useful to think of vacuum in terms of a gas at a pressure below atmospheric pressure. In even the best vacuum vessels ever created there are approximately 3,500,000 molecules of gas per cubic meter of volume remaining inside the vessel. The lowest pressure environment known is in interstellar space where there are approximately four molecules of gas per cubic meter. Researchers are currently developing vacuum technology components (pumps, gauges, valves, etc.) using micro electro mechanical systems (MEMS) technology. Miniature vacuum components and systems will open the possibility for significant savings in energy cost and will open the doors to advances in electronics, manufacturing and semiconductor fabrication. In conclusion, an understanding of the basic principles of vacuum technology as presented in this summary is essential for the successful execution of all projects that involve vacuum technology. Using the principles described above, a practitioner of vacuum technology can design a vacuum system that will achieve the project requirements.

  18. How reduced vacuum pumping capability in a coating chamber affects the laser damage resistance of HfO2/SiO2 antireflection and high reflection coatings.

    DOE PAGES

    Field, Ella Suzanne; Bellum, John Curtis; Kletecka, Damon E.

    2016-06-01

    Optical coatings with the highest laser damage thresholds rely on clean conditions in the vacuum chamber during the coating deposition process. A low base pressure in the coating chamber, as well as the ability of the vacuum system to maintain the required pressure during deposition, are important aspects of limiting the amount of defects in an optical coating that could induce laser damage. Our large optics coating chamber at Sandia National Laboratories normally relies on three cryo pumps to maintain low pressures for e-beam coating processes. However, on occasion, one or more of the cryo pumps have been out ofmore » commission. In light of this circumstance, we explored how deposition under compromised vacuum conditions resulting from the use of only one or two cryo pumps affects the laser-induced damage thresholds of optical coatings. Finally, the coatings of this study consist of HfO2 and SiO2 layer materials and include antireflection coatings for 527 nm at normal incidence, and high reflection coatings for 527 nm, 45⁰ angle of incidence (AOI), in P-polarization (P-pol).« less

  19. PUMPS

    DOEpatents

    Thornton, J.D.

    1959-03-24

    A pump is described for conveving liquids, particure it is not advisable he apparatus. The to be submerged in the liquid to be pumped, a conduit extending from the high-velocity nozzle of the injector,and means for applying a pulsating prcesure to the surface of the liquid in the conduit, whereby the surface oscillates between positions in the conduit. During the positive half- cycle of an applied pulse liquid is forced through the high velocity nozzle or jet of the injector and operates in the manner of the well known water injector and pumps liquid from the main intake to the outlet of the injector. During the negative half-cycle of the pulse liquid flows in reverse through the jet but no reverse pumping action takes place.

  20. Vacuum pump apparatus

    DOEpatents

    Batzer, Thomas H.; Call, Wayne R.

    1985-01-01

    An improved cryopumping apparatus which comprises a cryopumping space which may be alternately opened and closed from the surrounding area by moveable panels, trubular cryopanels within said cryopumping space through which a coolant such as liquid helium may be passed, and an apparatus for spraying liquid argon onto said cylindrical cryopanels in order to enhance the cryogenic entrapment of such low-z ions, atoms, and molecules as hydrogen and helium.

  1. Cryosorption of helium on argon frost TFTR (Tokamak Fusion Test Reactor) neutral beamlines

    SciTech Connect

    Kamperschroer, J.H.; Cropper, M.B.; Dylla, H.F.; Garzotto, V.; Dudek, L.E.; Grisham, L.R.; Martin, G.D.; O'Connor, T.E.; Stevenson, T.N.; von Halle, A. . Plasma Physics Lab.)

    1989-11-01

    Helium pumping on argon frost has been investigated on TFTR neutral beam injectors and shown to be viable for limited helium beam operation. Maximum pumping speeds are {approximately} 25% less than those measured for pumping of deuterium. Helium pumping efficiency is low, > 20 argon atoms are required to pump each helium atom. Adsorption isotherms are exponential and exhibit a two-fold increase in adsorption capacity as the cryopanel temperature is reduced from 4.3 K to 3.7 K. Pumping speed was found to be independent of cryopanel temperature over the temperature range studied. After pumping a total of 2000 torr-l of helium, the beamline base pressure rose to 2{times}10{sup -5} torr from an initial value of 10{sup -8} torr. Accompanying this three order of magnitude increase in pressure was a modest 40% decrease in pumping speed. The introduction of 168 torr-l of deuterium prior to helium injection reduced the pumping speed by a factor of two with no decrease in adsorption capacity. 29 refs., 7 figs.

  2. Gas bearing operates in vacuum

    NASA Technical Reports Server (NTRS)

    Perkins, G. S.

    1975-01-01

    Bearing has restrictions to reduce air leaks and is connected to external pumpout facility which removes exhausted air. Token amount of air which is lost to vacuum is easily removed by conventional vacuum pump.

  3. K-130 Cyclotron vacuum system

    NASA Astrophysics Data System (ADS)

    Yadav, R. C.; Bhattacharya, S.; Bhole, R. B.; Roy, Anindya; Pal, Sarbajit; Mallik, C.; Bhandari, R. K.

    2012-11-01

    The vacuum system for K-130 cyclotron has been operational since 1977. It consists of two sub-systems, main vacuum system and beam line vacuum system. The main vacuum system is designed to achieve and maintain vacuum of about 1 × 10-6 mbar inside the 23 m3 volume of acceleration chamber comprising the Resonator tank and the Dee tank. The beam line vacuum system is required for transporting the extracted beam with minimum loss. These vacuum systems consist of diffusion pumps backed by mechanical pumps like roots and rotary pumps. The large vacuum pumps and valves of the cyclotron vacuum system were operational for more than twenty five years. In recent times, problems of frequent failures and maintenance were occurring due to aging and lack of appropriate spares. Hence, modernisation of the vacuum systems was taken up in order to ensure a stable high voltage for radio frequency system and the extraction system. This is required for efficient acceleration and transportation of high intensity ion beam. The vacuum systems have been upgraded by replacing several pumps, valves, gauges and freon units. The relay based control system for main vacuum system has also been replaced by PLC based state of the art control system. The upgraded control system enables inclusion of additional operational logics and safety interlocks into the system. The paper presents the details of the vacuum system and describes the modifications carried out for improving the performance and reliability of the vacuum system.

  4. Stabilization of He2(A(sup 3)Sigma(sub u)(+)) molecules in liquid helium by optical pumping for vacuum UV laser

    NASA Technical Reports Server (NTRS)

    Zmuidzinas, J. S. (Inventor)

    1978-01-01

    A technique is disclosed for achieving large populations of metastable spin-aligned He2(a 3 Sigma u +) molecules in superfluid helium to obtain lasing in the vacuum ultraviolet wavelength regime around 0.0800 micron m by electronically exciting liquid (superfluid) helium with a comparatively low-current electron beam and spin aligning the metastable molecules by means of optical pumping with a modestly-powered (100mW) circularly-polarized continuous wave laser operating at, for example, 0.9096 or 0.4650 micron m. Once a high concentration of spin-aligned He2 (a 3 Sigma u +) is achieved with lifetimes of a few milliseconds, a strong microwave signal destroys the spin alignment and induces a quick collisional transition of He2 (a 3 Sigma u +) molecules to the a 1 Sigma u + state and thereby a lasing transition to the X 1 Sigma g + state.

  5. Time-Resolved UV-Pump (4.8eV) and Vacuum-UV (8eV) Probe Experiments of Neutral Excited State Dynamics

    NASA Astrophysics Data System (ADS)

    Horton, Spencer; Liu, Yusong; Matsika, Spiridoula; Weinacht, Thomas

    2016-05-01

    Excited state dynamics in polyatomic molecules involve a rich mixture of internal conversion, intersystem crossing, isomerization, and dissociation. Probing these dynamics with ultrafast laser pulses poses a number of challenges, in terms of both the execution of the measurements and their interpretation. We have developed an apparatus for probing excited state dynamics using a 260nm UV-pump pulse and a 156nm Vacuum-UV (VUV) probe pulse. For many systems of interest, an 8eV probe pulse can ionize the molecule from essentially any position along the excited state potential, while not having a background ionization yield from the ground state. Furthermore, given the perturbative interaction of each pulse with the molecule, it is possible interpret and model the experimental results with greater ease and confidence than more complicated probe interactions such as strong field ionization. We compare UV-IR strong-field ionization pump-probe experiments previously conducted directly with our 8eV probing and explore the differences between the two.

  6. TFTR diagnostic vacuum controller

    SciTech Connect

    Olsen, D.; Persons, R.

    1981-01-01

    The TFTR diagnostic vacuum controller (DVC) provides in conjunction with the Central Instrumentation Control and Data Acquisition System (CICADA), control and monitoring for the pumps, valves and gauges associated with each individual diagnostic vacuum system. There will be approximately 50 systems on TFTR. Two standard versions of the controller (A and B) wil be provided in order to meet the requirements of two diagnostic manifold arrangements. All pump and valve sequencing, as well as protection features, will be implemented by the controller.

  7. Edison's vacuum technology patents

    NASA Astrophysics Data System (ADS)

    Waits, Robert K.

    2003-07-01

    During 1879 Thomas Edison's Menlo Park, New Jersey laboratory developed the means to evacuate glass lamp globes to less than a mTorr in 20 min and in mid-1880 began production of carbon-filament incandescent lamps. Among Edison's nearly 1100 U.S. patents are five for vacuum pump improvements, and at least eight others that are vacuum-related; all applied for between 1880 and 1886. Inspired by an 1878 article by De La Rue and Müller [Philos. Trans. R. Soc. London, Ser. A 169, 155 (1878)] on studies of glow discharges, Edison devised a combination pump using the Geissler pump as a rough pump and the Sprengel pump for continuous exhaustion. Edison's patents described means to control the mercury flow and automate the delivery of the mercury to banks of up to a hundred pumps. Other patents described various means to remove residual gases during lamp processing.

  8. Channel electron multiplier operated on a sounding rocket without a cryogenic vacuum pump from 120 - 75 km altitude

    NASA Astrophysics Data System (ADS)

    Dickson, S.; Gausa, M. A.; Robertson, S. H.; Sternovsky, Z.

    2012-12-01

    We demonstrate that a channel electron multiplier (CEM) can be operated on a sounding rocket in the pulse-counting mode from 120 km to 75 km altitude without the cryogenic evacuation used in the past. Evacuation of the CEM is provided only by aerodynamic flow around the rocket. This demonstration is motivated by the need for additional flights of mass spectrometers to clarify the fate of metallic compounds and ions ablated from micrometeorites and their possible role in the nucleation of noctilucent clouds. The CEMs were flown as guest instruments on the two sounding rockets of the CHAMPS (CHarge And mass of Meteoritic smoke ParticleS) rocket campaign which were launched into the mesosphere in October 2011 from Andøya Rocket Range, Norway. Modeling of the aerodynamic flow around the payload with Direct Simulation Monte-Carlo (DSMC) code showed that the pressure is reduced below ambient in the void beneath an aft-facing surface. An enclosure containing the CEM was placed above an aft-facing deck and a valve was opened on the downleg to expose the CEM to the aerodynamically evacuated region below. The CEM operated successfully from apogee down to ~75 km. A Pirani gauge confirmed pressures reduced to as low as 20% of ambient with the extent of reduction dependent upon altitude and velocity. Additional DSMC simulations indicate that there are alternate payload designs with improved aerodynamic pumping for forward mounted instruments such as mass spectrometers.

  9. Channel electron multiplier operated on a sounding rocket without a cryogenic vacuum pump from 120 to 80 km altitude

    NASA Astrophysics Data System (ADS)

    Dickson, Shannon; Gausa, Michael; Robertson, Scott; Sternovsky, Zoltan

    2013-04-01

    We demonstrate that a channel electron multiplier (CEM) can be operated on a sounding rocket in the pulse-counting mode from 120 km to 80 km altitude without the cryogenic evacuation used in the past. Evacuation of the CEM is provided only by aerodynamic flow around the rocket. This demonstration is motivated by the need for additional flights of mass spectrometers to clarify the fate of metallic compounds and ions ablated from micrometeorites and their possible role in the nucleation of noctilucent clouds. The CEMs were flown as guest instruments on two sounding rockets to the mesosphere. Modeling of the aerodynamic flow around the payload with Direct Simulation Monte-Carlo (DSMC) code showed that the pressure is reduced below ambient in the void behind (relative to the direction of motion) an aft-facing surface. An enclosure containing the CEM was placed forward of an aft-facing deck and a valve was opened during flight to expose the CEM to the aerodynamically evacuated region behind it. The CEM operated successfully from apogee down to ∼80 km. A Pirani gauge confirmed pressures reduced to as low as 20% of ambient with the extent of reduction dependent upon altitude and velocity. Additional DSMC simulations indicate that there are alternate payload designs with improved aerodynamic pumping for forward mounted instruments such as mass spectrometers.

  10. Efficient baffle prevents oil backstreaming in diffusion pumps

    NASA Technical Reports Server (NTRS)

    Meneghetti, J. R.

    1972-01-01

    High vacuum diffusion pump baffle, positioned immediately above pump stack, prevents vaporized pumping oil from entering and contaminating test chamber. Pumping vapors are collected and condensed on the baffle and flow back to pump base reservoir.

  11. D-Zero Vacuum System

    SciTech Connect

    Wintercorn, S.J.; /Fermilab

    1986-04-07

    The system pumping speed was calculated by taking the reciprocal of the sum of the reciprocal pump speed and the reciprocal line conductances. The conductances of the pipe were calculated from the following formulas taken from the Varian vacuum manual. This report updates the original to reflect the pumping curves and basic vacuum system characteristics for the purchased components and installed piping of the D-Zero vacuum system. The system consists of two Edward's E2M275 two stage mechanical pumps, a Leybold-Heraeus WSU2000 Blower and three Varian 4' diffusion pumps (one for each cryostat). Individual pump and system pumping speed curves and a diagram of the system is included.

  12. R&D ERL: Vacuum

    SciTech Connect

    Mapes, M.; Smart, L.; Weiss, D.; Steszyn, A.; Todd, R.

    2010-01-01

    The ERL Vacuum systems are depicted in a figure. ERL has eight vacuum volumes with various sets of requirements. A summary of vacuum related requirements is provided in a table. Five of the eight volumes comprise the electron beamline. They are the 5-cell Superconducting RF Cavity, Superconducting e-gun, injection, loop and beam dump. Two vacuum regions are the individual cryostats insulating the 5-cell Superconducting RF Cavity and the Superconducting e-gun structures. The last ERL vacuum volume not shown in the schematic is the laser transport line. The beamline vacuum regions are separated by electropneumatic gate valves. The beam dump is common with loop beamline but is considered a separate volume due to geometry and requirements. Vacuum in the 5-cell SRF cavity is maintained in the {approx}10{sup -9} torr range at room temperature by two 20 l/s ion pumps and in the e-gun SRF cavity by one 60 l/s ion pump. Vacuum in the SRF cavities operated at 2{sup o}K is reduced to low 10{sup -11} torr via cryopumping of the cavity walls. The cathode of the e-gun must be protected from poisoning, which can occur if vacuum adjacent to the e-gun in the injection line exceeds 10-11 torr range in the injection warm beamline near the e-gun exit. The vacuum requirements for beam operation in the loop and beam dump are 10-9 torr range. The beamlines are evacuated from atmospheric pressure to high vacuum level with a particulate free, oil free turbomolecular pumping cart. 25 l/s shielded ion pumps distributed throughout the beamlines maintain the vacuum requirement. Due to the more demanding vacuum requirement of the injection beamline proximate to the e-gun, a vacuum bakeout of the injection beamline is required. In addition, two 200 l/s diode ion pumps and supplemental pumping provided by titanium sublimation pumps are installed in the injection line just beyond the exit of the e-gun. Due to expected gas load a similar pumping arrangement is planned for the beam dump. The

  13. How reduced vacuum pumping capability in a coating chamber affects the laser damage resistance of HfO2/SiO2 antireflection and high-reflection coatings

    NASA Astrophysics Data System (ADS)

    Field, Ella S.; Bellum, John C.; Kletecka, Damon E.

    2017-01-01

    Optical coatings with the highest laser damage thresholds rely on clean conditions in the vacuum chamber during the coating deposition process. A low-base pressure in the coating chamber, as well as the ability of the vacuum system to maintain the required pressure during deposition, are important aspects of limiting the amount of defects in an optical coating that could induce laser damage. Our large optics coating chamber at Sandia National Laboratories normally relies on three cryo pumps to maintain low pressures for e-beam coating processes. However, on occasion, one or more of the cryo pumps have been out of commission. In light of this circumstance, we explored how deposition under compromised vacuum conditions resulting from the use of only one or two cryo pumps affects the laser-induced damage thresholds of optical coatings. The coatings of this study consist of HfO2 and SiO2 layer materials and include antireflection coatings for 527 nm at normal incidence and high-reflection coatings for 527 nm at 45-deg angle of incidence in P-polarization.

  14. How reduced vacuum pumping capability in a coating chamber affects the laser damage resistance of HfO2/SiO2 antireflection and high reflection coatings.

    SciTech Connect

    Field, Ella Suzanne; Bellum, John Curtis; Kletecka, Damon E.

    2016-06-01

    Optical coatings with the highest laser damage thresholds rely on clean conditions in the vacuum chamber during the coating deposition process. A low base pressure in the coating chamber, as well as the ability of the vacuum system to maintain the required pressure during deposition, are important aspects of limiting the amount of defects in an optical coating that could induce laser damage. Our large optics coating chamber at Sandia National Laboratories normally relies on three cryo pumps to maintain low pressures for e-beam coating processes. However, on occasion, one or more of the cryo pumps have been out of commission. In light of this circumstance, we explored how deposition under compromised vacuum conditions resulting from the use of only one or two cryo pumps affects the laser-induced damage thresholds of optical coatings. Finally, the coatings of this study consist of HfO2 and SiO2 layer materials and include antireflection coatings for 527 nm at normal incidence, and high reflection coatings for 527 nm, 45⁰ angle of incidence (AOI), in P-polarization (P-pol).

  15. Precooler Ring Vacuum System

    SciTech Connect

    Moenich, J.

    1980-10-02

    The precooler vacuum system, as proposed by FNAL, is based on a suitable modification of the existing Electron Cooling Ring System. Because of the magnetic cycle of the bending magnets, distributed ion pumping, as exists in the Electron Cooling Ring, is not applicable. Instead, the proposed pumping will be done with commercial appendage ion pumps mounted approximately every two meters around the circumference of the ring. The loss of effective pumping speed and non-uniformity of system pressure with appendage pumps may not be major considerations but the large number required does effect experimental and analytical equipment placement considerations. There is a distributed pumping technique available which: (1) is not affected by the magnetic cycle of the bending magnets; (2) will provide a minimum of four times the hydrogen pumping speed of the proposed appendage ion pumps; (3) will require no power during pumping after the strip is activated; (4) will provide the heat source for bakeout; (5) is easily replaceable; and (6) can be purchased, installed, and operated at a generous economic advantage over the presently proposed ion pumped system. The pumping technique referred to is non-evaporable gettering with ST101 Zr/Al pumping strip. A technical description of this pumping strip is given on Data Sheet 1 and 2 attached to this report.

  16. ISABELLE vacuum systems

    SciTech Connect

    Halama, H J

    1980-01-01

    The Intersecting Storage Accelerator (ISABELLE) consists of two rings having a circumference of 3.8 km each. In these rings superconducting magnets, held at 4 K, bend and focus the proton beam which is accelerated up to 400 GeV. Due to very different pressure requirements, ISABELLE has two completely independent vacuum systems. One, which operates at 1 x 10/sup -11/ Torr, provides a very clean environment for the circulating proton beam. Here only ion and titanium sublimation pumps are used to provide the vacuum. The other system maintains superconducting magnet vessels at a pressure below 1 x 10/sup -4/ Torr, since at this pressure the gas conduction becomes negligible. In this so-called insulating vacuum system, turbomolecular pumps pump the inadvertent small helium leaks. Other gases are cryocondensed on the cold surfaces of the cryogenic system. The basic element of ISABELLE known as Full Cell containing 45 meters of beam tube, 8 pumping stations, 8 superconducting magnets and complete instrumentation has been constructed, leak checked and tested. All design parameters have been achieved in both vacuum systems. The two vacuum systems are described with particular emphasis on the influence of superconducting magnets in the selection of materials and UHV components.

  17. Air bearing vacuum seal assembly

    DOEpatents

    Booth, Rex

    1978-01-01

    An air bearing vacuum seal assembly capable of rotating at the speed of several thousand revolutions per minute using an air cushion to prevent the rotating and stationary parts from touching, and a two stage differential pumping arrangement to maintain the pressure gradient between the air cushion and the vacuum so that the leak rate into the vacuum is, for example, less than 1 .times. 10.sup.-4 Pa m.sup.3 /s. The air bearing vacuum seal has particular application for mounting rotating targets to an evacuated accelerator beam tube for bombardment of the targets with high-power charged particle beams in vacuum.

  18. ION PUMP

    DOEpatents

    Milleron, N.

    1961-01-01

    An ion pump and pumping method are given for low vacuum pressures in which gases introduced into a pumping cavity are ionized and thereafter directed and accelerated into a quantity of liquid gettering metal where they are absorbed. In the preferred embodiment the metal is disposed as a liquid pool upon one electrode of a Phillips ion gauge type pump. Means are provided for continuously and remotely withdrawing and degassing the gettering metal. The liquid gettering metal may be heated if desired, although various combinations of gallium, indium, tin, bismuth, and lead, the preferred metals, have very low melting points. A background pressure of evaporated gettering metal may be provided by means of a resistance heated refractory metal wick protruding from the surface of the pcol of gettering metal.

  19. Sorption vacuum trap

    NASA Technical Reports Server (NTRS)

    Barrington, A. E.; Caruso, A. J.

    1970-01-01

    Modified sorption trap for use in high vacuum systems contains provisions for online regeneration of sorbent material. Trap is so constructed that it has a number of encapsulated resistance heaters and a valving and pumping device for removing gases from heated sorbing material. Excessive downtime is eliminated with this trap.

  20. DIFFUSION PUMP

    DOEpatents

    Levenson, L.

    1963-09-01

    A high-vacuum diffusion pump is described, featuring a novel housing geometry for enhancing pumping speed. An upright, cylindrical lower housing portion is surmounted by a concentric, upright, cylindrical upper housing portion of substantially larger diameter; an uppermost nozzle, disposed concentrically within the upper portion, is adapted to eject downwardly a conical sheet of liquid outwardly to impinge upon the uppermost extremity of the interior wall of the lower portion. Preferably this nozzle is mounted upon a pedestal rising coaxially from within the lower portion and projecting up into said upper portion. (AEC)

  1. 14 CFR 29.1433 - Vacuum systems.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Vacuum systems. 29.1433 Section 29.1433... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Equipment Miscellaneous Equipment § 29.1433 Vacuum systems. (a... the discharge lines from the vacuum air pump when the delivery temperature of the air becomes...

  2. 14 CFR 29.1433 - Vacuum systems.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Vacuum systems. 29.1433 Section 29.1433... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Equipment Miscellaneous Equipment § 29.1433 Vacuum systems. (a... the discharge lines from the vacuum air pump when the delivery temperature of the air becomes...

  3. 14 CFR 25.1433 - Vacuum systems.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Vacuum systems. 25.1433 Section 25.1433... STANDARDS: TRANSPORT CATEGORY AIRPLANES Equipment Miscellaneous Equipment § 25.1433 Vacuum systems. There... discharge lines from the vacuum air pump when the delivery temperature of the air becomes unsafe....

  4. 14 CFR 25.1433 - Vacuum systems.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Vacuum systems. 25.1433 Section 25.1433... STANDARDS: TRANSPORT CATEGORY AIRPLANES Equipment Miscellaneous Equipment § 25.1433 Vacuum systems. There... discharge lines from the vacuum air pump when the delivery temperature of the air becomes unsafe....

  5. 14 CFR 25.1433 - Vacuum systems.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Vacuum systems. 25.1433 Section 25.1433... STANDARDS: TRANSPORT CATEGORY AIRPLANES Equipment Miscellaneous Equipment § 25.1433 Vacuum systems. There... discharge lines from the vacuum air pump when the delivery temperature of the air becomes unsafe....

  6. 14 CFR 25.1433 - Vacuum systems.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Vacuum systems. 25.1433 Section 25.1433... STANDARDS: TRANSPORT CATEGORY AIRPLANES Equipment Miscellaneous Equipment § 25.1433 Vacuum systems. There... discharge lines from the vacuum air pump when the delivery temperature of the air becomes unsafe....

  7. 14 CFR 29.1433 - Vacuum systems.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Vacuum systems. 29.1433 Section 29.1433... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Equipment Miscellaneous Equipment § 29.1433 Vacuum systems. (a... the discharge lines from the vacuum air pump when the delivery temperature of the air becomes...

  8. 14 CFR 25.1433 - Vacuum systems.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Vacuum systems. 25.1433 Section 25.1433... STANDARDS: TRANSPORT CATEGORY AIRPLANES Equipment Miscellaneous Equipment § 25.1433 Vacuum systems. There... discharge lines from the vacuum air pump when the delivery temperature of the air becomes unsafe....

  9. 14 CFR 29.1433 - Vacuum systems.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Vacuum systems. 29.1433 Section 29.1433... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Equipment Miscellaneous Equipment § 29.1433 Vacuum systems. (a... the discharge lines from the vacuum air pump when the delivery temperature of the air becomes...

  10. 14 CFR 29.1433 - Vacuum systems.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Vacuum systems. 29.1433 Section 29.1433... STANDARDS: TRANSPORT CATEGORY ROTORCRAFT Equipment Miscellaneous Equipment § 29.1433 Vacuum systems. (a... the discharge lines from the vacuum air pump when the delivery temperature of the air becomes...

  11. Alternative backing up pump for turbomolecular pumps

    DOEpatents

    Myneni, Ganapati Rao

    2003-04-22

    As an alternative to the use of a mechanical backing pump in the application of wide range turbomolecular pumps in ultra-high and extra high vacuum applications, palladium oxide is used to convert hydrogen present in the evacuation stream and related volumes to water with the water then being cryo-pumped to a low pressure of below about 1.e.sup.-3 Torr at 150.degree. K. Cryo-pumping is achieved using a low cost Kleemenco cycle cryocooler, a somewhat more expensive thermoelectric cooler, a Venturi cooler or a similar device to achieve the required minimization of hydrogen partial pressure.

  12. APS storage ring vacuum system

    SciTech Connect

    Niemann, R.C.; Benaroya, R.; Choi, M.; Dortwegt, R.J.; Goeppner, G.A.; Gonczy, J.; Krieger, C.; Howell, J.; Nielsen, R.W.; Roop, B.; Wehrle, R.B.

    1990-01-01

    The Advanced Photon Source synchrotron radiation facility, under construction at the Argonne National Laboratory, incorporates a large ring for the storage of 7 GeV positrons for the generation of photon beams for the facility's experimental program. The Storage Ring's 1104 m circumference is divided into 40 functional sectors. The sectors include vacuum, beam transport, control, acceleration and insertion device components. The vacuum system, which is designed to operate at a pressure of 1 n Torr, consists of 240 connected sections, the majority of which are fabricated from an aluminum alloy extrusion. The sections are equipped with distributed NeG pumping, photon absorbers with lumped pumping, beam position monitors, vacuum diagnostics and valving. The details of the vacuum system design, selected results of the development program and general construction plans are presented. 11 refs., 6 figs., 3 tabs.

  13. Results of a multi-site field treatability test for bioslurping: A comparison of LNAPL rates using vacuum-enhanced recovery (bioslurping), passive skimming, and pump drawdown recovery techniques. Field test report

    SciTech Connect

    Kittel, J.A.; Leeson, A.; Hinchee, R.E.; Miller, R.E.; Haas, P.E.

    1995-12-31

    Bioslurping is a new dynamic technology designed to efficiently recover free-floating petroleum hydrocarbons (free product) from the subsurface while simultaneously enhancing natural biodegradation of petroleum hydrocarbons in the vadose zone. Bioslurping is a vacuum-enhanced fluids pumping technology that simultaneously extracts groundwater, free product, and soil gas in the same process stream. The U.S. Air Force has initiated a multi-site program to evaluate the widespread application of bioslurping at free product-contaminated Air Force sites. The Air Force Bioslurper Initiative is designed to access the field application of the bioslurping technology at 36 Air Force sites. The field studies are designed to evaluate the efficacy of bioslurping for the recovery of free-floating fuel (free product) and to evaluate the potential for bioventing to enhance natural biodegradation of petroleum contaminants. The technical approach for conducting the bioslurper pilot tests includes assessing the geologic and hydrologic characteristics of each site, free-product baildown testing in site monitoring wells, soil gas analysis, and a bioslurper pump test. Bioslurping free-product recovery efficiency is compared to conventional skimming and dual-pump free-product recovery technologies, and bioventing potential is assessed via in situ respiration testing. The Air Force field program was initiated in July 1994. At the time of this writing, seven field tests have been completed. At each site bioslurping has yielded the highest LNAPL recovery rate. This paper presents a summary of LNAPL recovery data to date. Operational issues such as permitting and treatment of vapor and wastewater discharge will be discussed.

  14. Detail unit 5, showing discharge pipe and vacuum valve on ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Detail unit 5, showing discharge pipe and vacuum valve on discharge side of pump - Wellton-Mohawk Irrigation System, Pumping Plant No. 1, Bounded by Gila River & Union Pacific Railroad, Wellton, Yuma County, AZ

  15. Small solar pump for direct irrigation applications

    SciTech Connect

    Chadwick, D.G.; Willardson, L.S.

    1982-12-01

    A prototype solar powered water pump is described. The low-head vacuum lift pump uses a thermodynamic liquid to drive a floating piston which alternately draws water into a pumping chamber then pushes it past a check valve to a higher elevation. A discussion of typical crop requirements illustrates how this pump might be used in practice.

  16. THERMOCOUPLE VACUUM GAUGE

    DOEpatents

    Price, G.W.

    1954-08-01

    A protector device is described for use in controlling the pressure within a cyclotron. In particular, an electrical circuit functions to actuate a vacuum pump when a predetermined low pressure is reached and disconnect the pump when the pressure increases abcve a certain value. The principal feature of the control circuit lies in the use of a voltage divider network at the input to a relay control tube comprising two parallel, adjustable resistances wherein one resistor is switched into the circuit when the relay connects the pump to a power source. With this arrangement the relay is energized at one input level received from a sensing element within the cyclotron chamber and is de-energized when a second input level, representing the higher pressure limit, is reached.

  17. VACUUM TRAP

    DOEpatents

    Gordon, H.S.

    1959-09-15

    An improved adsorption vacuum trap for use in vacuum systems was designed. The distinguishing feature is the placement of a plurality of torsionally deformed metallic fins within a vacuum jacket extending from the walls to the central axis so that substantially all gas molecules pass through the jacket will impinge upon the fin surfaces. T fins are heated by direct metallic conduction, thereby ol taining a uniform temperature at the adeorbing surfaces so that essentially all of the condensible impurities from the evacuating gas are removed from the vacuum system.

  18. Vapor-barrier Vacuum Isolation System

    NASA Technical Reports Server (NTRS)

    Weinstein, Leonard M. (Inventor); Taminger, Karen M. (Inventor)

    2014-01-01

    A system includes a collimated beam source within a vacuum chamber, a condensable barrier gas, cooling material, a pump, and isolation chambers cooled by the cooling material to condense the barrier gas. Pressure levels of each isolation chamber are substantially greater than in the vacuum chamber. Coaxially-aligned orifices connect a working chamber, the isolation chambers, and the vacuum chamber. The pump evacuates uncondensed barrier gas. The barrier gas blocks entry of atmospheric vapor from the working chamber into the isolation chambers, and undergoes supersonic flow expansion upon entering each isolation chamber. A method includes connecting the isolation chambers to the vacuum chamber, directing vapor to a boundary with the working chamber, and supersonically expanding the vapor as it enters the isolation chambers via the orifices. The vapor condenses in each isolation chamber using the cooling material, and uncondensed vapor is pumped out of the isolation chambers via the pump.

  19. Multiple (Two) Met Bel 601 In Series Ultimate Vacuum Testing

    SciTech Connect

    Restivo, M.

    2016-09-30

    SRNL Environmental and Chemical Process Technology (E&CPT) was requested to perform testing of vacuum pumps per a verbal request from the Customer, SRNL Hydrogen Processing Technology. Tritium Operations is currently having difficulties procuring the Normetex™® Model 15 m3/hr (9 CFM) vacuum pump (formerly Normetex Pompes, now EumecaSARL). One possible solution proposed by Hydrogen Processing Technology personnel is to use two Senior Aerospace Metal Bellows MB-601 vacuum pumps piped with the heads in series, and the pumps in series (Figure 1 below). This memorandum documents the ultimate vacuum testing that was performed to determine if this concept was a viable alternate vacuum pump strategy. This testing dovetails with previous pump evaluations documented in references 1 and 2.

  20. Pump for molten metal or other fluid

    DOEpatents

    Horton, James A.; Brown, Donald L.

    1994-01-01

    A pump having no moving parts which can be used to pump high temperature molten metal or other fluids in a vacuum or low pressure environment, and a method for pumping such fluids. The pump combines elements of a bubble pump with a trap which isolates the vacuum or low pressure region from the gas used to create the bubbles. When used in a vacuum the trap prevents the pumping gas from escaping into the isolated region and thereby reducing the quality of the vacuum. The pump includes a channel in which a pumping gas is forced under pressure into a cavity where bubbles are formed. The cavity is in contact with a reservoir which contains the molten metal or other fluid which is to be pumped. The bubbles rise up into a column (or pump tube) carrying the fluid with them. At the top of the column is located a deflector which causes the bubbles to burst and the drops of pumped fluid to fall into a trap. The fluid accumulates in the trap, eventually forcing its way to an outlet. A roughing pump can be used to withdraw the pumping gas from the top of the column and assist with maintaining the vacuum or low pressure environment.

  1. Vacuum Virtues

    ERIC Educational Resources Information Center

    Rathey, Allen

    2007-01-01

    Upright vacuums, like cars, vary in quality, features and performance. Like automobiles, some uprights are reliable, others may be problematic, and some become a problem as a result of neglect or improper use. So, how do education institutions make an informed choice and, having done so, ensure that an upright vacuum goes the distance? In this…

  2. Vacuum mechatronics

    NASA Technical Reports Server (NTRS)

    Hackwood, Susan; Belinski, Steven E.; Beni, Gerardo

    1989-01-01

    The discipline of vacuum mechatronics is defined as the design and development of vacuum-compatible computer-controlled mechanisms for manipulating, sensing and testing in a vacuum environment. The importance of vacuum mechatronics is growing with an increased application of vacuum in space studies and in manufacturing for material processing, medicine, microelectronics, emission studies, lyophylisation, freeze drying and packaging. The quickly developing field of vacuum mechatronics will also be the driving force for the realization of an advanced era of totally enclosed clean manufacturing cells. High technology manufacturing has increasingly demanding requirements for precision manipulation, in situ process monitoring and contamination-free environments. To remove the contamination problems associated with human workers, the tendency in many manufacturing processes is to move towards total automation. This will become a requirement in the near future for e.g., microelectronics manufacturing. Automation in ultra-clean manufacturing environments is evolving into the concept of self-contained and fully enclosed manufacturing. A Self Contained Automated Robotic Factory (SCARF) is being developed as a flexible research facility for totally enclosed manufacturing. The construction and successful operation of a SCARF will provide a novel, flexible, self-contained, clean, vacuum manufacturing environment. SCARF also requires very high reliability and intelligent control. The trends in vacuum mechatronics and some of the key research issues are reviewed.

  3. Gravitational vacuum

    NASA Astrophysics Data System (ADS)

    Grigoryan, L. S.; Saakyan, G. S.

    1984-09-01

    The existence of a special gravitational vacuum is considered in this paper. A phenomenological method differing from the traditional Einsteinian formalization is utilized. Vacuum, metric and matter form a complex determined by field equations and at great distances from gravitational masses vacuum effects are small but could be large in powerful fields. Singularities and black holes justify the approach as well as the Ambartsmyan theory concerning the existence of supermassive and superdense prestallar bodies that then disintegrate. A theory for these superdense bodies is developed involving gravitational field equations that describe the vacuum by an energy momentum tensor and define the field and mass distribution. Computations based on the theory for gravitational radii with incompressible liquid models adequately reflecting real conditions indicate that a gravitational vacuum could have considerable effects on superdense stars and could have radical effects for very large masses.

  4. O.H. Module Vacuum Lifting Fixture

    SciTech Connect

    McGivern, Paul; /Fermilab

    1987-12-31

    In order to move the 800 lb. copper plates that make up the O.H. modules a vacuum lifting device has been made that will lift the plates safely. The purpose of this report is to provide documentation for the structural integrity of the system and to make sure that it passes all of the safety requirements that have been established for a system of this nature. The vacuum system is composed of a PIAB model M125 vacuum pump that has the pumping capacity of 27 in. Hg. This pump will produce vacuum for three 8 1/2 in. diameter suction cups or pads. A pressure gauge is fixed on the unit to allow the operator to continually monitor the pressure during all lifts. An additional safety feature is a mechanical vacuum monitoring device that is set to emit a shrill tone if the system vacuum falls below 24 in. Hg. A 'bleed' valve fixed on the unit will be used to let the system go to atmospheric pressure once the lift is complete. A 3 psi. check valve and a vacuum reserve of 384 in. is used to insure that the device will not just drop the object if the pump fails. A schematic for the pumping system is given in Figure 1.

  5. KEKB vacuum system

    NASA Astrophysics Data System (ADS)

    Kanazawa, K.; Kato, S.; Suetsugu, Y.; Hisamatsu, H.; Shimamoto, M.; Sato, M.; Shirai, M.

    2001-01-01

    For KEK B-factory (KEKB), two rings with a circumference of 3016 m, mainly made of copper have been constructed. One ring stores a maximum of 2.6 A positron beam with the energy at 3.5 GeV, the other stores 1.1 A, 8 GeV electron beam. These stored currents far exceed those of existing electron storage rings. The inside of a beam duct is designed to minimize an effect of beam induced fields. A gap between flanges is filled using Helicoflex as a vacuum seal. Contact force of a RF finger in a bellows is assured by the use of a spring finger. Pumping slots are backed by crossing bars to prevent the penetration of beam induced fields. To obtain a pressure of 10 -7 Pa with beam, a pumping speed is designed to realize 0.1 m 3 s -1 m -1 assuming that the photodesorption coefficient reaches 10 -6 molecules/photon. The NEG strip is used as a main pump element. Chemical polishing is applied to clean the extruded surface of copper chambers. Almost all chambers are baked before installation. Only ion pumps are baked in situ. From beginning to end, a completely oil free pumping system is used. The photodesorption coefficient at the start of the commissioning was slightly higher than expected, but the decrease of the coefficient is as expected on the whole. There is no trouble on the RF contact for bellows.

  6. VACUUM TRAP AND VALVE COMBINATION

    DOEpatents

    Milleron, N.; Levenson, L.

    1963-02-19

    This patent relates to a vacuum trap and valve combination suitable for use in large ultra-high vacuum systems. The vacuum trap is a chamber having an inlet and outlet opening which may be made to communicate with a chamber to be evacuated and a diffusion pump, respectively. A valve is designed to hermeticaliy seal with inlet opening and, when opened, block the line-of- sight'' between the inlet and outlet openings, while allowing a large flow path between the opened vaive and the side walls of the trap. The interior of the trap and the side of the valve facing the inlet opening are covered with an impurity absorbent, such as Zeolite or activated aluminum. Besides the advantage of combining two components of a vacuum system into one, the present invention removes the need for a baffle between the pump and the chamber to be evacuated. In one use of a specific embodiment of this invention, the transmission probability was 45 and the partial pressure of the pump fluid vapor in the vacuum chamber was at least 100 times lower than its vapor pressure. (AEC)

  7. An automated vacuum system

    SciTech Connect

    Atkins, W.H. ); Vaughn, G.D. ); Bridgman, C. )

    1991-01-01

    Software tools available with the Ground Test Accelerator (GTA) control system provide the capability to express a control problem as a finite state machine. System states and transitions are expressed in terms of accelerator parameters and actions are taken based on state transitions. This is particularly useful for sequencing operations which are modal in nature or are unwieldy when implemented with conventional programming. State diagrams are automatically translated into code which is executed by the control system. These tools have been applied to the vacuum system for the GTA accelerator to implement automatic sequencing of operations. With a single request, the operator may initiate a complete pump-down sequence. He can monitor the progress and is notified if an anomaly occurs requiring intervention. The operator is not required to have detailed knowledge of the vacuum system and is protected from taking inappropriate actions. 1 ref., 6 figs.

  8. Vacuum coupling of rotating superconducting rotor

    DOEpatents

    Shoykhet, Boris A.; Zhang, Burt Xudong; Driscoll, David Infante

    2003-12-02

    A rotating coupling allows a vacuum chamber in the rotor of a superconducting electric motor to be continually pumped out. The coupling consists of at least two concentric portions, one of which is allowed to rotate and the other of which is stationary. The coupling is located on the non-drive end of the rotor and is connected to a coolant supply and a vacuum pump. The coupling is smaller in diameter than the shaft of the rotor so that the shaft can be increased in diameter without having to increase the size of the vacuum seal.

  9. RENEWABLE LIQUID GETTERING PUMP

    DOEpatents

    Batzer, T.H.

    1962-08-21

    A method and structure were developed for pumping gases by simple absorption into a liquid gettering material. The invention comprises means ror continuously pumping a liquid getterrng material from a reservoir to the top of a generally vertical surface disposed in a vacuum pumping chamber to receive gaseous and other particles in the liquid gettering material which continuously flows downward over the vertical suiface. Means are provided for continuous removal, degassing, and return of a portion of the liquid gettering material from the reservoir connected with collectrng means at the base of the generally vertical plate. (AEC)

  10. MEANS AND METHOD FOR PRODUCING A VACUUM

    DOEpatents

    Otavka, M.A.

    1960-08-01

    A new method is given for starting the operation of evapor-ion vacuum pumps. Ordinarily this type of pump is started by inducing an electric field with the vacuum chamber; however, by placing such an electric field in the chamber at the outset, a glow discharge may be initiated which is harmful to the pump. The procedure consists of using a negative electric field during which time only gettering action takes place; subsequently when the field reverses after a sufficient reduction of the number of gaseous particles in the chamber both gettering and ionizing takes place.

  11. [Ambulant treatment of wounds by vacuum sealing].

    PubMed

    Ziegler, U E; Schmidt, K; Breithaupt, B; Menig, R; Debus, E S; Thiede, A

    2000-01-01

    The treatment of chronic wounds by vacuum sealing as an outpatient procedure is a new method of wound conditioning before closing the defect. The quality of life for the patient in his usual surrounding is maintained. Financial aspects also play a role in this treatment since costs for the health care system can be reduced. Various vacuum pumps, drainages and polymere foams are available and suitable for the outpatient treatment. The most important condition is to regularly check the vacuum. This can performed by the patient, the relatives or nursing staff. The main complication consists in loss of vacuum but technical and local or systemic complications can also appear. Individually applied vacuum dressings (polyvinyl foam, drainage tube and polymere foil) are practical. The ideal pump systems for the outpatient treatment are still not trial.

  12. Vacuum Technology Considerations For Mass Metrology

    PubMed Central

    Abbott, Patrick J.; Jabour, Zeina J.

    2011-01-01

    Vacuum weighing of mass artifacts eliminates the necessity of air buoyancy correction and its contribution to the measurement uncertainty. Vacuum weighing is also an important process in the experiments currently underway for the redefinition of the SI mass unit, the kilogram. Creating the optimum vacuum environment for mass metrology requires careful design and selection of construction materials, plumbing components, pumping, and pressure gauging technologies. We review the vacuum technology1 required for mass metrology and suggest procedures and hardware for successful and reproducible operation. PMID:26989593

  13. HOM Effects in Vacuum System with Short Bunches

    SciTech Connect

    Novokhatski, A.; /SLAC

    2005-06-10

    High luminosity in electron-positron factories requires high currents of very short bunches. SLAC PEP-II and KEKB B-factories are progressively increasing currents gaining more and more luminosity [1-2]. Simultaneously the interaction of high currents and vacuum chamber elements becomes more important for operation of the rings. High Order Modes excited by short intense bunches are propagating along the vacuum chamber, penetrating and dissipating inside vital vacuum elements, like shielded bellows, vacuum valves and vacuum pump. As a result, these elements get large temperature rise or temperature oscillations. Often HOM heating has a resonance character. HOM heating of vacuum pumps leads to increasing of the vacuum pressure. High frequency modes ''check'' the quality of vacuum chamber: they detect small gaps, weak RF screens or feed-through. Smooth tapers and collimators become the source of HOM production. We will discuss the physical nature of these exciting HOM effects.

  14. Autonomous pump against concentration gradient

    PubMed Central

    Xu, Zhi-cheng; Zheng, Dong-qin; Ai, Bao-quan; Zhong, Wei-rong

    2016-01-01

    Using non-equilibrium molecular dynamics and Monte Carlo methods, we have studied the molecular transport in asymmetric nanochannels. The efficiency of the molecular pump depends on the angle and apertures of the asymmetric channel, the environmental temperature and average concentration of the particles. The pumping effect can be explained as the competition between the molecular force field and the thermal disturbance. Our results provide a green approach for pumping fluid particles against the concentration gradient through asymmetric nanoscale thin films without any external forces. It indicates that pumping vacuum can be a spontaneous process. PMID:26996204

  15. Very-Low-Cost, Rugged Vacuum System

    NASA Technical Reports Server (NTRS)

    Kline-Schoder, Robert; Sorensen, Paul; Passow, Christian; Bilski, Steve

    2013-01-01

    NASA, DoD, DHS, and commercial industry have a need for miniaturized, rugged, low-cost vacuum systems. Recent advances in sensor technology have led to the development of very small mass spectrometer detectors as well as other miniature analytical instruments. However, the vacuum systems to support these sensors remain large, heavy, and power-hungry. To meet this need, a miniaturized vacuum system was created based on a very small, rugged, and inexpensive- to-manufacture molecular drag pump (MDP). The MDP is enabled by the development of a miniature, veryhigh- speed, rugged, low-power, brushless DC motor optimized for wide temperature operation and long life. Such a pump represents an order-of-magnitude reduction in mass, volume, and cost over current, commercially available, state-ofthe- art vacuum pumps. The vacuum system consists of the MDP coupled to a ruggedized rough pump (for terrestrial applications or for planets with substantial atmospheres). The rotor in the MDP consists of a simple smooth cylinder of aluminum spinning at approximately 200,000 RPM inside an outer stator housing. The pump stator comprises a cylindrical aluminum housing with one or more specially designed grooves that serve as flow channels. To minimize the length of the pump, the gas is forced down the flow channels of the outer stator to the base of the pump. The gas is then turned and pulled toward the top through a second set of channels cut into an inner stator housing that surrounds the motor. The compressed gas then flows down channels in the motor housing to the exhaust port of the pump. The exhaust port of the pump is connected to a diaphragm or scroll pump. This pump delivers very high performance in a very small envelope. The design was simplified so that a smaller compression ratio, easier manufacturing process, and enhanced ruggedness can be achieved at the lowest possible cost. The machining of the rotor and stators is very simple compared to that necessary to fabricate TMP

  16. Deposition of non evaporable getter films and their vacuum performance

    NASA Astrophysics Data System (ADS)

    Bansod, Tripti; Sindal, B. K.; Kumar, Kvanps; Shukla, S. K.

    2012-06-01

    Use of NEG coating as an integrated pump in accelerators is state of art technique to pump them in UHV range. At UHVTD, RRCAT development of these coatings has also been started. A UHV compatible cylindrical DC magnetron sputtering system was developed for this purpose and evolution of optimized NEG coating parameters is under investigation. Ti-Zr-V NEG films were coated on 400mm and 925mm long chamber with 100mm diameter. Preliminary vacuum performances like ultimate vacuum testing and activation studies with CO pumping for a NEG chamber were studied, which clearly demonstrates large pumping speed for CO.

  17. Magnetic shielding and vacuum test for passive hydrogen masers

    NASA Technical Reports Server (NTRS)

    Gubser, D. U.; Wolf, S. A.; Jacoby, A. B.; Jones, L. D.

    1982-01-01

    Vibration tests on high permeability magnetic shields used in the SAO-NRL Advanced Development Model (ADM) hydrogen maser were made. Magnetic shielding factors were measured before and after vibration. Preliminary results indicate considerable (25%) degradation. Test results on the NRL designed vacuum pumping station for the ADM hydrogen maser are also discussed. This system employs sintered zirconium carbon getter pumps to pump hydrogen plus small ion pumps to pump the inert gases. In situ activation tests and pumping characteristics indicate that the system can meet design specifications.

  18. Two-color bright squeezed vacuum

    SciTech Connect

    Agafonov, Ivan N.; Chekhova, Maria V.

    2010-07-15

    In a strongly pumped nondegenerate traveling-wave optical parametric amplifier, we produce a two-color squeezed vacuum with up to millions of photons per pulse. Our approach to registering this macroscopic quantum state is direct detection of a large number of transverse and longitudinal modes, which is achieved by making the detection time and area much larger than the coherence time and area, respectively. Using this approach, we obtain a record value of twin-beam squeezing for direct detection of bright squeezed vacuum. This makes direct detection of macroscopic squeezed vacuum a practical tool for quantum information applications.

  19. Microscale Thermal-Transpiration Gas Pump

    NASA Technical Reports Server (NTRS)

    Vargo, Stephen; Muntz, Phillip; Shiflett, Geoff

    2003-01-01

    A recent addition to the growing class of microelectromechanical systems (MEMS) is a single stage of a Knudsen compressor. This device was fabricated and tested to demonstrate the feasibility of Knudsen compressors as miniature vacuum pumps for future portable scientific instruments. The attributes of Knudsen compressors that make them attractive as miniature vacuum pumps are that they contain no moving parts and operate without need for lubricants or working fluids.

  20. Quartz crystals detect gas contaminants during vacuum chamber evacuation

    NASA Technical Reports Server (NTRS)

    Stephens, J. B.

    1967-01-01

    Piezoelectric quartz crystals detect condensable gas contaminants backstreaming into a vacuum chamber when a pump is evacuating the chamber. One crystal acts as a thermometer, the other detects mass change. They are energized by electronic equipment which records frequency changes.

  1. Vacuum bell therapy

    PubMed Central

    Sesia, Sergio

    2016-01-01

    Background For specific therapy to correct pectus excavatum (PE), conservative treatment with the vacuum bell (VB) was introduced more than 10 years ago in addition to surgical repair. Preliminary results using the VB were encouraging. We report on our 13-year experience with the VB treatment including the intraoperative use during the Nuss procedure and present some technical innovations. Methods A VB with a patient-activated hand pump is used to create a vacuum at the anterior chest wall. Three different sizes of vacuum bells, as well as a model fitted for young women, exist. The appropriate size is selected according to the individual patient’s age and ventral surface. The device should be used at home for a minimum of 30 minutes (twice a day), and may be used up to a maximum of several hours daily. The intensity of the applied negative pressure can be evaluated with an integrated pressure gauge during follow-up visits. A prototype of an electronic model enables us to measure the correlation between the applied negative pressure and the elevation of the anterior chest wall. Results Since 2003, approx. 450 patients between 2 to 61 years of age started the VB therapy. Age and gender specific differences, depth of PE, symmetry or asymmetry, and concomitant malformations such as scoliosis and/or kyphosis influence the clinical course and success of VB therapy. According to our experience, we see three different groups of patients. Immediate elevation of the sternum was confirmed thoracoscopically during the Nuss procedure in every patient. Conclusions The VB therapy has been established as an alternative therapeutic option in selected patients suffering from PE. The initial results up to now are encouraging, but long-term results comprising more than 15 years are so far lacking, and further evaluation and follow-up studies are necessary. PMID:27747177

  2. Superconducting cyclotron and its vacuum system

    NASA Astrophysics Data System (ADS)

    Sur, A.; Bhandari, R. K.

    2008-05-01

    A large superconducting cyclotron is under construction at this Centre and will be used to accelerate heavy ion beams to energy up to 80 MeV/A for light heavy ions and about 10 MeV/A for medium mass heavy ions. The vacuum system for this accelerator has several different aspects. The main acceleration chamber will be evacuated to a level of about 10-7 torr using both turbo molecular pumps and specially designed cryopanels. The surfaces exposed to this 'vacuum' are mostly made of OFE copper. The cryogenic transfer lines, to cool the cryopanels, are of several meters in length and they pass through RF resonators extending below the magnet. The cryostat that will house the superconducting coils has an annular vacuum chamber, which is evacuated to a level of approximately 10-5 torr using a turbo molecular pump. Cryopumping action starts once the coils are cooled to low temperatures. A differential pumping is provided below the RF liner that encloses the pole tip of the main magnet. The space that is pumped in this case contains epoxy-potted trim coils wound around the pole tips. Crucial interlocks are provided between the differential vacuum and the acceleration chamber vacuum to avoid distortion of the RF liner, which is made of thin copper sheets. The other important vacuum system provides thermal insulation for the liquid helium transfer lines. In this paper a brief description of the superconducting cyclotron will be given. Details of various vacuum aspects of the accelerator and the logistics of their operation will be presented. Introduction of some of the improved equipment now available and improved techniques are also discussed.

  3. PLASMA WINDOW FOR VACUUM - ATMOSPHERE INTERFACE AND FOCUSING LENS OF SOURCES FOR NON-VACUUM MATERIAL MODIFICATION.

    SciTech Connect

    HERSHCOVITCH,A.

    1997-09-07

    Material modifications by ion implantation, dry etching, and micro-fabrication are widely used technologies, all of which are performed in vacuum, since ion beams at energies used in these applications are completely attenuated by foils or by long differentially pumped sections, which ate currently used to interface between vacuum and atmosphere. A novel plasma window, which utilizes a short arc for vacuum-atmosphere interface has been developed. This window provides for sufficient vacuum atmosphere separation, as well as for ion beam propagation through it, thus facilitating non-vacuum ion material modification.

  4. DC photogun vacuum characterization through photocathode lifetime studies

    SciTech Connect

    Marcy Stutzman; Joseph Grames; Matt Poelker; Kenneth Surles-Law; Philip Adderley

    2007-07-02

    Excellent vacuum is essential for long photocathode lifetimes in DC high voltage photoelectron guns. Vacuum Research at Thomas Jefferson National Accelerator Facility has focused on characterizing the existing vacuum systems at the CEBAF polarized photoinjector and on quantifying improvements for new systems. Vacuum chamber preprocessing, full activation of NEG pumps and NEG coating the chamber walls should improve the vacuum within the electron gun, however, pressure measurement is difficult at pressures approaching the extreme-high-vacuum (XHV) region and extractor gauge readings are not significantly different between the improved and original systems. The ultimate test of vacuum in a DC high voltage photogun is the photocathode lifetime, which is limited by the ionization and back-bombardment of residual gasses. Discussion will include our new load-locked gun design as well as lifetime measurements in both our operational and new photo-guns, and the correlations between measured vacuum and lifetimes will be investigated.

  5. Antechamber facilitates loading and unloading of vacuum furnace

    NASA Technical Reports Server (NTRS)

    Kramer, P. J.; Mills, J. A.; Orth, N. W.; Quatinetz, M.; Wagner, J. G.

    1968-01-01

    Antechamber facilitates the use of a furnace in which materials are heat treated in a high vacuum or a gas atmosphere. It has a high vacuum pumping system, a means for backfilling with a selected gas, an access door, glove ports, and a motor driven platform.

  6. 40 CFR 1065.345 - Vacuum-side leak verification.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... start of the first test interval of each duty-cycle sequence, and after maintenance such as pre-filter... sampling system on the vehicle, prior to the start of the field test, and after maintenance such as pre...) Operate all vacuum pumps. After stabilizing, verify that the flow through the vacuum-side of the...

  7. 40 CFR 1065.345 - Vacuum-side leak verification.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... start of the first test interval of each duty-cycle sequence, and after maintenance such as pre-filter... sampling system on the vehicle, prior to the start of the field test, and after maintenance such as pre...) Operate all vacuum pumps. After stabilizing, verify that the flow through the vacuum-side of the...

  8. 40 CFR 1065.345 - Vacuum-side leak verification.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... start of the first test interval of each duty-cycle sequence, and after maintenance such as pre-filter... sampling system on the vehicle, prior to the start of the field test, and after maintenance such as pre...) Operate all vacuum pumps. After stabilizing, verify that the flow through the vacuum-side of the...

  9. 40 CFR 1065.345 - Vacuum-side leak verification.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... start of the first test interval of each duty-cycle sequence, and after maintenance such as pre-filter... sampling system on the vehicle, prior to the start of the field test, and after maintenance such as pre...) Operate all vacuum pumps. After stabilizing, verify that the flow through the vacuum-side of the...

  10. PUMP CONSTRUCTION

    DOEpatents

    Strickland, G.; Horn, F.L.; White, H.T.

    1960-09-27

    A pump which utilizes the fluid being pumped through it as its lubricating fluid is described. This is achieved by means of an improved bearing construction in a pump of the enclosed or canned rotor type. At the outlet end of the pump, adjacent to an impeller mechanism, there is a bypass which conveys some of the pumped fluid to a chamber at the inlet end of the pump. After this chamber becomes full, the pumped fluid passes through fixed orifices in the top of the chamber and exerts a thrust on the inlet end of the pump rotor. Lubrication of the rotor shaft is accomplished by passing the pumped fluid through a bypass at the outlet end of the rotor shaft. This bypass conveys Pumped fluid to a cooling means and then to grooves on the surface of the rotor shait, thus lubricating the shaft.

  11. Industrial Pumps

    NASA Technical Reports Server (NTRS)

    1986-01-01

    A flow inducer is a device that increases the pump intake capacity of a Worthington Centrifugal pump. It lifts the suction pressure sufficiently for the rotating main impeller of the centrifugal pump to operate efficiently at higher fluid intake levels. The concept derives from 1960's NASA technology which was advanced by Worthington Pump Division. The pumps are used to recirculate wood molasses, a highly viscous substance.

  12. VIEW OF THE HEATING ELEMENTS AND VACUUM GAUGE OF A ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW OF THE HEATING ELEMENTS AND VACUUM GAUGE OF A PUMP-DOWN STATION IN BUILDING 991. THE PUMP-DOWN STATION REMOVED OUT-GASES FROM INSIDE THE TRIGGERS. (9/26/61) - Rocky Flats Plant, Final Assembly & Shipping, Eastern portion of plant site, south of Spruce Avenue, east of Tenth Street & north of Central Avenue, Golden, Jefferson County, CO

  13. Pressure pulsations above turbomolecular pumps

    NASA Technical Reports Server (NTRS)

    Danziger, S.; Kendall, B. R. F.; Dormer, J.

    1982-01-01

    Lange and Singleton (1978) have observed pressure pulses above a turbomolecular pump. They reported that the mean pulse frequency increased with the temperature of the pump cooling water and that the evolved gas was mainly hydrogen. The present investigation takes into account tests conducted with a similar pumping system. The pumping system was equipped with additional pressure-monitoring equipment in order to study these pulsations in more detail. It was found that at least two distinct types of pressure pulsations may be present in a turbomolecular-pumped ultrahigh vacuum system. The random hydrogen pulses are easily eliminated for period of days by changing the cooling water temperature. The cyclic pulses consisting mainly of water vapor are not likely to be a problem in normal experiments.

  14. Large-capacity pump vaporizer for liquid hydrogen and nitrogen

    NASA Technical Reports Server (NTRS)

    Hauser, J. A.

    1970-01-01

    Pump vaporizer system delivers 500 standard cubic feet per minute of hydrogen or nitrogen, one system delivers both gases. Vacuum-jacketed pump discharges liquid hydrogen or liquid nitrogen into vaporizing system heated by ambient air. Principal characteristics of the flow and discharge system, pump, and vaporizer are given.

  15. Miniature Lightweight Ion Pump

    NASA Technical Reports Server (NTRS)

    Sinha, Mahadeva P.

    2010-01-01

    This design offers a larger surface area for pumping of active gases and reduces the mass of the pump by eliminating the additional vacuum enclosure. There are three main components to this ion pump: the cathode and anode pumping elements assembly, the vacuum enclosure (made completely of titanium and used as the cathode and maintained at ground potential) containing the assembly, and the external magnet. These components are generally put in a noble diode (or differential) configuration of the ion pump technology. In the present state of the art, there are two cathodes, one made of titanium and the other of tantalum. The anodes are made up of an array of stainless steel cylinders positioned between the two cathodes. All the elements of the pump are in a vacuum enclosure. After the reduction of pressure in this enclosure to a few microns, a voltage is applied between the cathode and the anode elements. Electrons generated by the ionization are accelerated toward the anodes that are confined in the anode space by the axial magnetic field. For the generation of the axial field along the anode elements, the magnet is designed in a C-configuration and is fabricated from rare earth magnetic materials (Nd-B-Fe or Sm-Co) possessing high energy product values, and the yoke is fabricated from the high permeability material (Hiperco-50A composed of Fe-Co-V). The electrons in this region collide with the gas molecules and generate their positive ions. These ions are accelerated into the cathode and eject cathode material (Ti). The neutral atoms deposit on the anode surfaces. Because of the chemical activity of Ti, the atoms combine with chemically active gas molecules (e.g. N2, O2, etc.) and remove them. New layers of Ti are continually deposited, and the pumping of active gases is thus accomplished. Pumping of the inert gases is accomplished by their burial several atomic layers deep into the cathode. However, they tend to re-emit if the entrapping lattice atoms are

  16. Vacuum system of the cyclotrons in VECC, Kolkata

    SciTech Connect

    Roy, Anindya; Bhole, R.B.; Akhtar, J.; Yadav, R.C.; Pal, Sarbajit; Sarkar, D.; Bhandari, R.K. E-mail: rbb@vecc.gov.in E-mail: yadav@vecc.gov.in E-mail: dsarkar@vecc.gov.in

    2011-07-01

    The vacuum system of the K=130 Room Temperature Cyclotron (RTC) (operational since 1978) has been recently modernized and the same of the K{sub bend}=520 Superconducting Cyclotron (SCC), currently under commissioning, is being deployed for remote monitoring and control. The vacuum system of RTC is designed to achieve and maintain vacuum level of 2 X 10{sup -6} mbar inside 23 m{sup 3} volume of Resonator tank and DEE tank. This has been upgraded by replacing several valves, Freon units, gauges and pumps. The relay based manual control system has been replaced by PLC based automated system. The SCC vacuum system also has an elaborate arrangement comprising of turbo molecular pumping modules with associated isolation valves and characteristic gauges. This paper describes essential elements, typically used to obtain high (1X10{sup -7} mbar) vacuum using rotary pumps, diffusion pumps and cold traps/turbo-molecular pumps and other system components such as valves, gauges and baffles. The supervisory control methodology/scheme of both the vacuum systems, developed in-house using EPICS (Experimental Physics and Industrial Control System), a standard open-source software tool for designing distributed control system, is also elaborated here. (author)

  17. Venturi Air-Jet Vacuum Ejector For Sampling Air

    NASA Technical Reports Server (NTRS)

    Hill, Gerald F.; Sachse, Glen W.; Burney, L. Garland; Wade, Larry O.

    1990-01-01

    Venturi air-jet vacuum ejector pump light in weight, requires no electrical power, does not contribute heat to aircraft, and provides high pumping speeds at moderate suctions. High-pressure motive gas required for this type of pump bled from compressor of aircraft engine with negligible effect on performance of engine. Used as source of vacuum for differential-absorption CO-measurement (DACOM), modified to achieve in situ measurements of CO at frequency response of 10 Hz. Provides improvement in spatial resolution and potentially leads to capability to measure turbulent flux of CO by use of eddy-correlation technique.

  18. Degradation of the lunar vacuum by a moon base

    NASA Astrophysics Data System (ADS)

    Landis, G. A.

    1990-03-01

    Several industrial processes requiring high and ultra-high vacuum similar to the lunar vacuum are outlined. The effects of a 20-person lunar base and a 250-person industrial facility on this vacuum are discussed. It is shown that exhaust from transport spacecraft and leakage from the habitat will be comparable to the daytime gas pressure for the 20-person base, and will degrade the vacuum to the range of 2 x 10 to the -9th torr for the use of 250-person facility. This will result in replacing the mostly nonreactive gases hydrogen, helium, and neon with more reactive gases containing carbon and oxygen. This vacuum is still good enough to perform many important vacuum processes such as plasma-deposition of amorphous silicon for solar cells, but processes such as molecular beam epitaxy or locating an intersecting beam accelerator on the moon will require additional vacuum pumping.

  19. Degradation of the lunar vacuum by a moon base

    NASA Technical Reports Server (NTRS)

    Landis, Geoffrey

    1990-01-01

    Several industrial processes requiring high and ultra-high vacuum similar to the lunar vacuum are outlined. The effects of a 20-person lunar base and a 250-person industrial facility on this vacuum are discussed. It is shown that exhaust from transport spacecraft and leakage from the habitat will be comparable to the daytime gas pressure for the 20-person base, and will degrade the vacuum to the range of 2 x 10 to the -9th torr for the use of 250-person facility. This will result in replacing the mostly nonreactive gases hydrogen, helium, and neon with more reactive gases containing carbon and oxygen. This vacuum is still good enough to perform many important vacuum processes such as plasma-deposition of amorphous silicon for solar cells, but processes such as molecular beam epitaxy or locating an intersecting beam accelerator on the moon will require additional vacuum pumping.

  20. The vacuum system of KEKB

    NASA Astrophysics Data System (ADS)

    Kanazawa, K.; Kato, S.; Suetsugu, Y.; Hisamatsu, H.; Shimamoto, M.; Shirai, M.

    2003-02-01

    For the KEK B-factory, two rings with a circumference of 3016 m, mainly made of copper, were constructed. A gap between the flanges is filled using Helicoflex as a vacuum seal. The contact force of an RF finger in a bellows is assured by using a spring finger. Pumping slots are backed by crossing bars to prevent the penetration of beam-induced fields. To obtain a pressure of 10 -9 Torr with the beam when the photo-desorption coefficient reaches 10 -6, the design of pump layout is aimed to realize 100 ℓ s-1 m-1. NEG strips are used as the main pump. Chemical polishing is applied to clean the extruded surface of a copper chamber. Almost all chambers were baked before installation. Only ion pumps were baked in situ. The photo-desorption coefficient at the start of commissioning was slightly higher than expected, but a decrease of the coefficient is as expected on the whole. At high currents, some bellows were found to be warmed by the TE mode of beam induced fields. The effect of the electron cloud became evident, especially in the LER. Direct damage by the beam is seen at the surface of the movable mask.

  1. Germanium detector vacuum encapsulation

    NASA Technical Reports Server (NTRS)

    Madden, N. W.; Malone, D. F.; Pehl, R. H.; Cork, C. P.; Luke, P. N.; Landis, D. A.; Pollard, M. J.

    1991-01-01

    This paper describes an encapsulation technology that should significantly improve the viability of germanium gamma-ray detectors for a number of important applications. A specialized vacuum chamber has been constructed in which the detector and the encapsulating module are processed in high vacuum. Very high vacuum conductance is achieved within the valveless encapsulating module. The detector module is then sealed without breaking the chamber vacuum. The details of the vacuum chamber, valveless module, processing, and sealing method are presented.

  2. Magnetocaloric pump

    NASA Technical Reports Server (NTRS)

    Brown, G. V.

    1973-01-01

    Very cold liquids and gases such as helium, neon, and nitrogen can be pumped by using magnetocaloric effect. Adiabatic magnetization and demagnetization are used to alternately heat and cool slug of pumped fluid contained in closed chamber.

  3. Heat pumps

    NASA Astrophysics Data System (ADS)

    Gilli, P. V.

    1982-11-01

    Heat pumps for residential/commercial space heating and hot tap water make use of free energy of direct or indirect solar heat and save from about 40 to about 70 percent of energy if compared to a conventional heating system with the same energy basis. In addition, the electrically driven compressor heat pump is able to substitute between 40% (bivalent alternative operation) to 100% (monovalent operation) of the fuel oil of an oilfired heating furnace. For average Central European conditions, solar space heating systems with high solar coverage factor show the following sequence of increasing cost effectiveness: pure solar systems (without heat pumps); heat pump assisted solar systems; solar assisted heat pump systems; subsoil/water heat pumps; air/water heat pumps; air/air heat pumps.

  4. Vacuum chamber-free centrifuge with magnetic bearings.

    PubMed

    Park, Cheol Hoon; Kim, Soohyun; Kim, Kyung-Soo

    2013-09-01

    Centrifuges are devices that separate particles of different densities and sizes through the application of a centrifugal force. If a centrifuge could be operated under atmospheric conditions, all vacuum-related components such as the vacuum chamber, vacuum pump, diffusion pump, and sealing could be removed from a conventional centrifuge system. The design and manufacturing procedure for centrifuges could then be greatly simplified to facilitate the production of lightweight centrifuge systems of smaller volume. Furthermore, the maintenance costs incurred owing to wear and tear due to conventional ball bearings would be eliminated. In this study, we describe a novel vacuum chamber-free centrifuge supported by magnetic bearings. We demonstrate the feasibility of the vacuum chamber-free centrifuge by presenting experimental results that verify its high-speed support capability and motoring power capacity.

  5. Nature's pumps

    NASA Astrophysics Data System (ADS)

    Vogel, Steven

    1994-10-01

    Although diverse in both form and function, the fluid-forcing devices in organisms have many of the capabilities and limitations of pumps of human design. Nature's pumps certainly look quite different from those of our technology, but all of them perform the same task. The author examines a few of these with an eye toward technological parallels and the two functional classes -- positive-displacement pumps and fluid-dynamic pumps.

  6. ELECTROMAGNETIC PUMP

    DOEpatents

    Pulley, O.O.

    1954-08-17

    This patent reiates to electromagnetic pumps for electricity-conducting fluids and, in particular, describes several modifications for a linear conduction type electromagnetic interaction pump. The invention resides in passing the return conductor for the current traversing the fiuid in the duct back through the gap in the iron circuit of the pump. Both the maximum allowable pressure and the efficiency of a linear conduction electromagnetic pump are increased by incorporation of the present invention.

  7. Vacuum system for Advanced Test Accelerator

    SciTech Connect

    Denhoy, B.S.

    1981-09-03

    The Advanced Test Accelerator (ATA) is a pulsed linear electron beam accelerator designed to study charged particle beam propagation. ATA is designed to produce a 10,000 amp 50 MeV, 70 ns electron beam. The electron beam acceleration is accomplished in ferrite loaded cells. Each cell is capable of maintaining a 70 ns 250 kV voltage pulse across a 1 inch gap. The electron beam is contained in a 5 inch diameter, 300 foot long tube. Cryopumps turbomolecular pumps, and mechanical pumps are used to maintain a base pressure of 2 x 10/sup -6/ torr in the beam tube. The accelerator will be installed in an underground tunnel. Due to the radiation environment in the tunnel, the controlling and monitoring of the vacuum equipment, pressures and temperatures will be done from the control room through a computer interface. This paper describes the vacuum system design, the type of vacuum pumps specified, the reasons behind the selection of the pumps and the techniques used for computer interfacing.

  8. Vacuum still bottoms viscometer

    SciTech Connect

    Dinsmore, T.V.; Wilson, J.H.

    1985-01-01

    A viscometer system that is capable of measuring VSB viscosity on-line has been designed, constructed, and tested. The viscometer will not only provide continuous on-line measurements for process control purposes, but will also determine viscosity as functions of temperature and shear rate. The latter results may be used to verify design-base information for direct coal liquefaction demonstration plants. The viscosities of Wilsonville samples of VSB and LSRC were determined as functions of shear rate and, in the case of LSRC, temperature. The VSB viscosity was found to be shear-rate sensitive, while the LSRC viscosity was temperature sensitive. A 24-h test run was unsuccessful, apparently because the check valves in the pump plugged; however, all other mechanical, electrical, and electronic equipment operated satisfactorily. The source of the plugging was thought to be degradation products, which should not cause difficulties in the pilot plant where fresh vacuum bottoms feed is always available. In summary, the results obtained in this study indicate that the viscometer system is ready to be transported to a plant such as Wilsonville and operated on-line. 7 figs., 5 tabs.

  9. Cryogenic Viscous Compressor Development and Modeling for the ITER Vacuum System

    SciTech Connect

    Baylor, Larry R; Meitner, Steven J; Barbier, Charlotte N; Combs, Stephen Kirk; Duckworth, Robert C; Edgemon, Timothy D; Rasmussen, David A; Hechler, Michael P; Kersevan, R.; Dremel, M.; Pearce, R.J.H.; Boissin, Jean Claude

    2011-01-01

    The ITER vacuum system requires a roughing pump system that can pump the exhaust gas from the torus cryopumps to the tritium exhaust processing plant. The gas will have a high tritium content and therefore conventional vacuum pumps are not suitable. A pump called a cryogenic viscous compressor (CVC) is being designed for the roughing system to pump from ~500 Pa to 10 Pa at flow rates of 200 Pa-m3/ s. A unique feature of this pump is that is allows any helium in the gas to flow through the pump where it is sent to the detritiation system before exhausting to atmosphere. A small scale prototype of the CVC is being tested for heat transfer characteristics and compared to modeling results to ensure reliable operation of the full scale CVC. Keywords- ITER; vacuum; fuel cycle

  10. OSCILLATORY PUMP

    DOEpatents

    Underwood, N.

    1958-09-23

    This patent relates to a pump suitable fur pumping highly corrosive gases wherein no lubricant is needed in the pumping chamber thus eliminating possible contamination sources. The chamber contains a gas inlet and outlet in each side, with a paddle like piston suspended by a sylphon seal between these pcrts. An external arrangement causes the paddle to oscillate rapidly between the ports, alternately compressing and exhausting the gas trapped on each side of the paddle. Since the paddle does nnt touch the chamber sides at any point, no lubricant is required. This pump is useful for pumping large quantities of uranium hexafluorine.

  11. Vacuum-assisted delivery

    MedlinePlus

    ... this page: //medlineplus.gov/ency/patientinstructions/000514.htm Vacuum-assisted delivery To use the sharing features on ... the baby through the birth canal. When is Vacuum-assisted Delivery Needed? Even after your cervix is ...

  12. The vacuum system of IHI's compact SOR ``LUNA''

    NASA Astrophysics Data System (ADS)

    Oishi, M.; Uesaka, M.; Mandai, S.; Nishidono, T.; Nakashizu, T.; Hoshi, Y.

    1991-08-01

    The construction of the 800 MeV compact synchrotron light sources ``LUNA'' was completed in April 1989 at Tsuchiura Facility of IHI. 20 mA beam have been successfully accelerated up to 800 MeV and accumulated with the lifetime of more than 30 min. Now, the machine study and modifications are being done in order to get more accumulated beam currents and longer lifetime. In most of vacuum sections, the static vacuum pressure of less than 1x10E-7 Pa has been obtained and in the presence of synchrotron radiation, the vacuum pressure is measured as less than 1x10E-6 Pa. The SUS316L vacuum chambers were baked at 200 C For 70 hours in total. The surfaces of the vacuum chambers were treated with buff polishing, acid and freon flashing cleaning. In the 23 meters long vacuum system, ten 400 liter/sec ion pumps and 15 cartridge type nonevaporable getter (NEG) pumps are installed and the total vacuum pumping capacity is 6660 liter/sec. Additional, the beam channels for X-ray lithography and other experiments are going to be constructed in 1991.

  13. Radiation hard vacuum switch

    DOEpatents

    Boettcher, Gordon E.

    1990-03-06

    A vacuum switch with an isolated trigger probe which is not directly connected to the switching electrodes. The vacuum switch within the plasmatron is triggered by plasma expansion initiated by the trigger probe which travels through an opening to reach the vacuum switch elements. The plasma arc created is directed by the opening to the space between the anode and cathode of the vacuum switch to cause conduction.

  14. Radiation hard vacuum switch

    DOEpatents

    Boettcher, Gordon E.

    1990-01-01

    A vacuum switch with an isolated trigger probe which is not directly connected to the switching electrodes. The vacuum switch within the plasmatron is triggered by plasma expansion initiated by the trigger probe which travels through an opening to reach the vacuum switch elements. The plasma arc created is directed by the opening to the space between the anode and cathode of the vacuum switch to cause conduction.

  15. Miniature Scroll Pumps Fabricated by LIGA

    NASA Technical Reports Server (NTRS)

    Wiberg, Dean; Shcheglov, Kirill; White, Victor; Bae, Sam

    2009-01-01

    Miniature scroll pumps have been proposed as roughing pumps (low - vacuum pumps) for miniature scientific instruments (e.g., portable mass spectrometers and gas analyzers) that depend on vacuum. The larger scroll pumps used as roughing pumps in some older vacuum systems are fabricated by conventional machining. Typically, such an older scroll pump includes (1) an electric motor with an eccentric shaft to generate orbital motion of a scroll and (2) conventional bearings to restrict the orbital motion to a circle. The proposed miniature scroll pumps would differ from the prior, larger ones in both design and fabrication. A miniature scroll pump would include two scrolls: one mounted on a stationary baseplate and one on a flexure stage (see figure). An electromagnetic actuator in the form of two pairs of voice coils in a push-pull configuration would make the flexure stage move in the desired circular orbit. The capacitance between the scrolls would be monitored to provide position (gap) feedback to a control system that would adjust the drive signals applied to the voice coils to maintain the circular orbit as needed for precise sealing of the scrolls. To minimize power consumption and maximize precision of control, the flexure stage would be driven at the frequency of its mechanical resonance. The miniaturization of these pumps would entail both operational and manufacturing tolerances of <1 m. Such tight tolerances cannot be achieved easily by conventional machining of high-aspect-ratio structures like those of scroll-pump components. In addition, the vibrations of conventional motors and ball bearings exceed these tight tolerances by an order of magnitude. Therefore, the proposed pumps would be fabricated by the microfabrication method known by the German acronym LIGA ( lithographie, galvanoformung, abformung, which means lithography, electroforming, molding) because LIGA has been shown to be capable of providing the required tolerances at large aspect ratios.

  16. The Classical Vacuum.

    ERIC Educational Resources Information Center

    Boyer, Timothy H.

    1985-01-01

    The classical vacuum of physics is not empty, but contains a distinctive pattern of electromagnetic fields. Discovery of the vacuum, thermal spectrum, classical electron theory, zero-point spectrum, and effects of acceleration are discussed. Connection between thermal radiation and the classical vacuum reveals unexpected unity in the laws of…

  17. The PEP-II Lower Pressure HER Vacuum Chamber

    SciTech Connect

    DeBarger, S.; Metcalfe, S.; Seeman, J.; Sullivan, M.; Wienands, U.; Wright, D.; /SLAC

    2006-03-13

    This new vacuum chamber has been installed from 12 to 21 meters upstream of the BaBar detector in the PEP-II High Energy Ring (HER) to reduce lost particle backgrounds. The backgrounds from HER now dominate the backgrounds in the BaBar detector and the present vacuum pressure is 1 x 10{sup -9} Torr. The new chamber will increase the pumping significantly by adding 18 x 2000 l/s titanium sublimation pumps to the existing 5 x 440 l/s ion pumps, and is expected to reduce the pressure by about a factor of five. Features of the chamber include improved water cooling, improved vacuum conductance through copper RF screens featuring over 15,000 small square holes and the ability to sublimate titanium while the beam is still on.

  18. Low-Cost, Rugged High-Vacuum System

    NASA Technical Reports Server (NTRS)

    Sorensen, Paul; Kline-Schoder, Robert

    2012-01-01

    A need exists for miniaturized, rugged, low-cost high-vacuum systems. Recent advances in sensor technology have led to the development of very small mass spectrometer detectors as well as other analytical instruments such as scanning electron microscopes. However, the vacuum systems to support these sensors remain large, heavy, and power-hungry. To meet this need, a miniaturized vacuum system was developed based on a very small, rugged, and inexpensive-to-manufacture molecular drag pump (MDP). The MDP is enabled by a miniature, very-high-speed (200,000 rpm), rugged, low-power, brushless DC motor optimized for wide temperature operation and long life. The key advantages of the pump are reduced cost and improved ruggedness compared to other mechanical hig-hvacuum pumps. The machining of the rotor and stators is very simple compared to that necessary to fabricate rotor and stator blades for other pump designs. Also, the symmetry of the rotor is such that dynamic balancing of the rotor will likely not be necessary. Finally, the number of parts in the unit is cut by nearly a factor of three over competing designs. The new pump forms the heart of a complete vacuum system optimized to support analytical instruments in terrestrial applications and on spacecraft and planetary landers. The MDP achieves high vacuum coupled to a ruggedized diaphragm rough pump. Instead of the relatively complicated rotor and stator blades used in turbomolecular pumps, the rotor in the MDP consists of a simple, smooth cylinder of aluminum. This will turn at approximately 200,000 rpm inside an outer stator housing. The pump stator comprises a cylindrical aluminum housing with one or more specially designed grooves that serve as flow channels. To minimize the length of the pump, the gas is forced down the flow channels of the outer stator to the base of the pump. The gas is then turned and pulled toward the top through a second set of channels cut into an inner stator housing that surrounds the

  19. Development and Implementation of an Ultrafast Vacuum-UV (8eV) Light Source for use in UV-VUV Pump Probe Experiments of Neutral Excited State Dynamics

    NASA Astrophysics Data System (ADS)

    Liu, Yusong; Horton, Spencer; Matsika, Spiridoula; Weinacht, Thomas

    2016-05-01

    Probing neutral excited state dynamics in polyatomic molecules with ultrafast laser systems enables us to study phenomena such as internal conversion, isomerization, intersystem crossing, and dissociation. Using the third harmonic (260 nm) and the fifth harmonic (156 nm) of our laser system we have developed an apparatus to perform pump-probe experiments for the study neutral excited state dynamics in various polyatomic molecules. The fifth harmonic of our laser system is generated through the four-wave-mixing process of k5 ω = 2k3 ω -kω performed with a non-collinear geometry in an argon gas cell. In several polyatomic molecular systems of interest a photon with 8 eV of energy gives us the unique ability to ionize from essentially anywhere along the excited state potential, but does not produce any ionization yield from the ground state. This enables us to measure excited state lifetimes without the photon energy becoming too low to ionize while the nuclear wave-packet is traveling on the excited state potential. We also have the advantage of working in the perturbative weak-field ionization regime. These experiments can also be directly compare to strong-field ionization experiments conducted with a UV-pump and an IR-probe conducted on the same molecules.

  20. Self-pumping impurity control

    DOEpatents

    Brooks, J.N.; Mattas, R.F.

    1983-12-21

    It is an object of the present invention to provide an apparatus for removing impurities from the plasma in a fusion reactor without an external vacuum pumping system. It is also an object of the present invention to provide an apparatus for removing the helium ash from a fusion reactor. It is another object of the present invention to provide an apparatus which removes helium ash and minimizes tritium recycling and inventory.

  1. Axial Pump

    NASA Technical Reports Server (NTRS)

    Bozeman, Richard J., Jr. (Inventor); Akkerman, James W. (Inventor); Aber, Gregory S. (Inventor); VanDamm, George Arthur (Inventor); Bacak, James W. (Inventor); Svejkovsky, Paul A. (Inventor); Benkowski, Robert J. (Inventor)

    1997-01-01

    A rotary blood pump includes a pump housing for receiving a flow straightener, a rotor mounted on rotor bearings and having an inducer portion and an impeller portion, and a diffuser. The entrance angle, outlet angle, axial and radial clearances of blades associated with the flow straightener, inducer portion, impeller portion and diffuser are optimized to minimize hemolysis while maintaining pump efficiency. The rotor bearing includes a bearing chamber that is filled with cross-linked blood or other bio-compatible material. A back emf integrated circuit regulates rotor operation and a microcomputer may be used to control one or more back emf integrated circuits. A plurality of magnets are disposed in each of a plurality of impeller blades with a small air gap. A stator may be axially adjusted on the pump housing to absorb bearing load and maximize pump efficiency.

  2. Pumping system

    SciTech Connect

    Kime, J.A.

    1987-05-19

    This patent describes a gas-oil production system for pumping formation fluid in a well through a tubing string within which a down hole pump connects to a hydraulic stroking device through a rod string providing the pump including a plunger reciprocally driven by the hydraulic stroking device toward an upper terminal position during a plunger upstroke. The rod string normally supports the weight of a column of fluid and toward a lower terminal position at the end of a plunger downstroke during which the weight of the column fluid is normally transferred to the tubing string through fluid within the pump. The method for detecting when the well is pumped off comprises: supplying working fluid to the hydraulic stroking device to raise the hydraulic stroking device and thereby move the plunger from the lower terminal position to the upper terminal position; and removing the working fluid at a controlled rate from the hydraulic stroking device.

  3. Ferroelectric Pump

    NASA Technical Reports Server (NTRS)

    Jalink, Antony, Jr. (Inventor); Hellbaum, Richard F. (Inventor); Rohrbach, Wayne W. (Inventor)

    2000-01-01

    A ferroelectric pump has one or more variable volume pumping chambers internal to a housing. Each chamber has at least one wall comprising a dome shaped internally prestressed ferroelectric actuator having a curvature and a dome height that varies with an electric voltage applied between an inside and outside surface of the actuator. A pumped medium flows into and out of each pumping chamber in response to displacement of the ferroelectric actuator. The ferroelectric actuator is mounted within each wall and isolates each ferroelectric actuator from the pumped medium, supplies a path for voltage to be applied to each ferroelectric actuator, and provides for positive containment of each ferroelectric actuator while allowing displacement of the entirety of each ferroelectric actuator in response to the applied voltage.

  4. Indian Vacuum Society: The Indian Vacuum Society

    NASA Astrophysics Data System (ADS)

    Saha, T. K.

    2008-03-01

    The Indian Vacuum Society (IVS) was established in 1970. It has over 800 members including many from Industry and R & D Institutions spread throughout India. The society has an active chapter at Kolkata. The society was formed with the main aim to promote, encourage and develop the growth of Vacuum Science, Techniques and Applications in India. In order to achieve this aim it has conducted a number of short term courses at graduate and technician levels on vacuum science and technology on topics ranging from low vacuum to ultrahigh vacuum So far it has conducted 39 such courses at different parts of the country and imparted training to more than 1200 persons in the field. Some of these courses were in-plant training courses conducted on the premises of the establishment and designed to take care of the special needs of the establishment. IVS also regularly conducts national and international seminars and symposia on vacuum science and technology with special emphasis on some theme related to applications of vacuum. A large number of delegates from all over India take part in the deliberations of such seminars and symposia and present their work. IVS also arranges technical visits to different industries and research institutes. The society also helped in the UNESCO sponsored post-graduate level courses in vacuum science, technology and applications conducted by Mumbai University. The society has also designed a certificate and diploma course for graduate level students studying vacuum science and technology and has submitted a syllabus to the academic council of the University of Mumbai for their approval, we hope that some colleges affiliated to the university will start this course from the coming academic year. IVS extended its support in standardizing many of the vacuum instruments and played a vital role in helping to set up a Regional Testing Centre along with BARC. As part of the development of vacuum education, the society arranges the participation of

  5. A vacuum-driven peristaltic micropump with valved actuation chambers

    NASA Astrophysics Data System (ADS)

    Cui, Jianguo; Pan, Tingrui

    2011-06-01

    This paper presents a simple peristaltic micropump design incorporated with valved actuation chambers and propelled by a pulsed vacuum source. The vacuum-driven peristaltic micropump offers high pumping rates, low backflow, appreciable tolerance to air bubbles, and minimal destruction to fluid contents. The pumping device, fabricated by laser micromachining and plasma bonding of three polydimethylsiloxane (PDMS) layers, includes a pneumatic network, actuation membranes, and microfluidic channels. As the key to peristaltic motion, the sequential deflection of the elastic membranes is achieved by periodic pressure waveforms (negative) traveling through the pneumatic network, provided by a vacuum source regulated by an electromagnetic valve. This configuration eliminates the complicated control logic typically required in peristaltic motion. Importantly, the valved actuation chambers substantially reduce backflow and improve the pumping rates. In addition, the pneumatic network with negative pressure provides a means to effectively remove air bubbles present in the microflow through the gas-permeable PDMS membrane, which can be highly desired in handling complex fluidic samples. Experimental characterization of the micropump performance has been conducted by controlling the resistance of the pneumatic network, the number of normally closed valves, the vacuum pressure, and the frequency of pressure pulses. A maximal flow rate of 600 µL min-1 has been optimized at the pulsed vacuum frequency of 30 Hz with a vacuum pressure of 50 kPa, which is comparable to that of compressed air-actuated peristaltic micropumps.

  6. TRIUMF cyclotron vacuum system refurbishing

    NASA Astrophysics Data System (ADS)

    Sekachev, I.

    2008-03-01

    The cyclotron at TRIUMF was commissioned to full energy in 1974. The volume of the cyclotron vacuum tank is about 100 m3 and it operates at 5×10-8 Torr pressure during beam production. The pumping is mainly based on a Phillips B-20 cryogenerator (Stirling cycle 4-cylinder engine). The cryogenerator supplies helium gas at 16 K and 70 K to cryopanels in the tank. The decreasing reliability of the B-20 and demanding maintenance requirements triggered the decision to completely overhaul or replace the cryogenerator. Replacement with the LINDE-1630 helium refrigerator was found to be the most attractive (technically and economically) option. The details of the proposal with installation of the helium refrigerator and with a continuous flow liquid nitrogen shield cooling system are presented.

  7. Submersible pump

    SciTech Connect

    Todd, D. B.

    1985-08-27

    A method and apparatus for using a submersible pump to lift reservoir fluids in a well while having the tubing/casing annulus isolated from the produced fluids. The apparatus allows the submersible pump to be positioned above the annular packoff device. The apparatus comprises an outer shield that encloses the pump and can be attached to the production tubing. The lower end of the shield attaches to a short tubing section that seals with the annular packoff device or a receptacle above the annular packoff device.

  8. Water Pump Development for the EVA PLSS

    NASA Technical Reports Server (NTRS)

    Schuller, Michael; Kurwitz, Cable; Goldman, Jeff; Morris, Kim; Trevino, Luis

    2009-01-01

    This paper describes the effort by the Texas Engineering Experiment Station (TEES) and Honeywell for NASA to design, fabricate, and test a preflight prototype pump for use in the Extravehicular activity (EVA) portable life support subsystem (PLSS). Major design decisions were driven by the need to reduce the pump s mass, power, and volume compared to the existing PLSS pump. In addition, the pump will accommodate a much wider range of abnormal conditions than the existing pump, including vapor/gas bubbles and increased pressure drop when employed to cool two suits simultaneously. A positive displacement, external gear type pump was selected because it offers the most compact and highest efficiency solution over the required range of flow rates and pressure drops. An additional benefit of selecting a gear pump design is that it is self priming and capable of ingesting noncondensable gas without becoming "air locked." The chosen pump design consists of a 28 V DC, brushless, sealless, permanent magnet motor driven, external gear pump that utilizes a Honeywell development that eliminates the need for magnetic coupling. Although the planned flight unit will use a sensorless motor with custom designed controller, the preflight prototype to be provided for this project incorporates Hall effect sensors, allowing an interface with a readily available commercial motor controller. This design approach reduced the cost of this project and gives NASA more flexibility in future PLSS laboratory testing. The pump design was based on existing Honeywell designs, but incorporated features specifically for the PLSS application, including all of the key features of the flight pump. Testing at TEES will simulate the vacuum environment in which the flight pump will operate. Testing will verify that the pump meets design requirements for range of flow rates, pressure rise, power consumption, working fluid temperature, operating time, and restart capability. Pump testing is currently

  9. Cleaning of a thermal vacuum chamber with shrouds in place

    NASA Technical Reports Server (NTRS)

    Bond, William R.

    1992-01-01

    In February, 1991, a failure of a rotary booster pump caused the diffusion pumps to backstream into a 10 ft x 15 ft thermal vacuum chamber. Concerns existed about the difficulty of removing and reinstalling the shrouds without causing leaks. The time required for the shroud removal was also of concern. These concerns prompted us to attempt to clean the chamber without removing the shrouds.

  10. Maintaining vacuum furnaces

    SciTech Connect

    Kowalewski, J.

    2000-04-01

    A preventive maintenance program is essential for safe and consistent vacuum furnace operation. The program should be developed in cooperation with safety, maintenance, and furnace operators, implemented as soon as the furnace is commissioned, and adhered to throughout the life of the furnace. This article serves as an introduction to the topic of vacuum furnace preventive maintenance. Basic information about installing a new vacuum furnace also is provided.

  11. Vacuum probe surface sampler

    NASA Technical Reports Server (NTRS)

    Zahlava, B. A. (Inventor)

    1973-01-01

    A vacuum probe surface sampler is described for rapidly sampling relatively large surface areas which possess relatively light loading densities of micro-organism, drug particles or the like. A vacuum head with a hollow handle connected to a suitable vacuum source is frictionally attached to a cone assembly terminating in a flared tip adapted to be passed over the surface to be sampled. A fine mesh screen carried by the vacuum head provides support for a membrane filter which collects the microorganisms or other particles. The head assembly is easily removed from the cone assembly without contacting the cone assembly with human hands.

  12. Electrokinetic pump

    DOEpatents

    Patel, Kamlesh D.

    2007-11-20

    A method for altering the surface properties of a particle bed. In application, the method pertains particularly to an electrokinetic pump configuration where nanoparticles are bonded to the surface of the stationary phase to alter the surface properties of the stationary phase including the surface area and/or the zeta potential and thus improve the efficiency and operating range of these pumps. By functionalizing the nanoparticles to change the zeta potential the electrokinetic pump is rendered capable of operating with working fluids having pH values that can range from 2-10 generally and acidic working fluids in particular. For applications in which the pump is intended to handle highly acidic solutions latex nanoparticles that are quaternary amine functionalized can be used.

  13. Coherence and multimode correlations from vacuum fluctuations in a microwave superconducting cavity

    NASA Astrophysics Data System (ADS)

    Lähteenmäki, Pasi; Paraoanu, Gheorghe Sorin; Hassel, Juha; Hakonen, Pertti J.

    2016-08-01

    The existence of vacuum fluctuations is one of the most important predictions of modern quantum field theory. In the vacuum state, fluctuations occurring at different frequencies are uncorrelated. However, if a parameter in the Lagrangian of the field is modulated by an external pump, vacuum fluctuations stimulate spontaneous downconversion processes, creating squeezing between modes symmetric with respect to half of the frequency of the pump. Here we show that by double parametric pumping of a superconducting microwave cavity, it is possible to generate another type of correlation, namely coherence between photons in separate frequency modes. The coherence correlations are tunable by the phases of the pumps and are established by a quantum fluctuation that stimulates the simultaneous creation of two photon pairs. Our analysis indicates that the origin of this vacuum-induced coherence is the absence of which-way information in the frequency space.

  14. Coherence and multimode correlations from vacuum fluctuations in a microwave superconducting cavity

    PubMed Central

    Lähteenmäki, Pasi; Paraoanu, Gheorghe Sorin; Hassel, Juha; Hakonen, Pertti J.

    2016-01-01

    The existence of vacuum fluctuations is one of the most important predictions of modern quantum field theory. In the vacuum state, fluctuations occurring at different frequencies are uncorrelated. However, if a parameter in the Lagrangian of the field is modulated by an external pump, vacuum fluctuations stimulate spontaneous downconversion processes, creating squeezing between modes symmetric with respect to half of the frequency of the pump. Here we show that by double parametric pumping of a superconducting microwave cavity, it is possible to generate another type of correlation, namely coherence between photons in separate frequency modes. The coherence correlations are tunable by the phases of the pumps and are established by a quantum fluctuation that stimulates the simultaneous creation of two photon pairs. Our analysis indicates that the origin of this vacuum-induced coherence is the absence of which-way information in the frequency space. PMID:27562246

  15. Slurry pumping: Pump performance prediction

    SciTech Connect

    Taccani, R.; Pediroda, V.; Reini, M.; Giadrossi, A.

    2000-07-01

    Centrifugal pumps are being used increasingly for transportation of slurries through pipelines. To design a slurry handling system it is essential to have a knowledge of the effects of suspended solids on the pump performance. A new test loop has been realized in the laboratory of the Energetics Department of the University of Trieste which allows pump performance to be determined at various pump speeds, with many different mixture concentrations and rheologies. The pump test rig consists of 150 mm diameter pipe with facilities for measuring suction and discharge pressure, flowrate, pump input power and speed, slurry density and temperature. In particular flowrate is measured by diverting flow into a weighing tank and timing a specified volume of slurry. An automatic PC based data acquisition system has been implemented. Preliminary tests with clear water show that performance can be measured with good repeatability and accuracy. The new test rig is used to verify the range of validity of the correlations to predict pump performance, available in literature and of that proposed by authors. This correlation, based on a Neural Network and not on a predefined analytical expression, can be easily improved with new experimental data.

  16. Ultra-high vacuum in superconducting accelerator rings

    NASA Astrophysics Data System (ADS)

    Bazanov, A. M.; Butenko, A. V.; Galimov, A. R.; Lugovnin, A. K.; Smirnov, A. V.

    2016-12-01

    Achieving the ultra-high vacuum (UHV) in the collider and booster of the NICA project is one of the main challenges when creating this device. It determines the need for a serious approach to this issue and conducting research in this direction. First, it is necessary to understand the effect of the various components of the vacuum systems on the degree of vacuum. It is also necessary to carry out studies of pumping devices for producing the required vacuum (10-9 Pa) in the beam chamber and choose the most optimal pumping scheme. At the same time, it is necessary to figure out how various operations are carried out with the vacuum chamber: preparation of vacuum surfaces, letting in the atmosphere, and warming the chamber after closing the influence on the degree of vacuum and the composition of the residual gas. The temperature may vary from room temperature to liquid helium temperature due to the difficulty of keeping the beam-chamber walls at a constant temperature, including the inner components. This complicates the processes taking place within it. Additional complexity arises due the heating of the chamber walls by various processes during the operation of the accelerator (for example, cycling the magnetic field).

  17. Differentially pumped dual linear quadrupole ion trap mass spectrometer

    DOEpatents

    Owen, Benjamin C.; Kenttamaa, Hilkka I.

    2016-11-15

    The present disclosure provides a new tandem mass spectrometer and methods of using the same for analyzing charged particles. The differentially pumped dual linear quadrupole ion trap mass spectrometer of the present disclose includes a combination of two linear quadrupole (LQIT) mass spectrometers with differentially pumped vacuum chambers.

  18. Differentially pumped dual linear quadrupole ion trap mass spectrometer

    DOEpatents

    Owen, Benjamin C.; Kenttamaa, Hilkka I.

    2015-10-20

    The present disclosure provides a new tandem mass spectrometer and methods of using the same for analyzing charged particles. The differentially pumped dual linear quadrupole ion trap mass spectrometer of the present disclose includes a combination of two linear quadrupole (LQIT) mass spectrometers with differentially pumped vacuum chambers.

  19. Fuel pump

    SciTech Connect

    Bellis, P.D.; Nesselrode, F.

    1991-04-16

    This patent describes a fuel pump. It includes: a fuel reservoir member, the fuel reservoir member being formed with fuel chambers, the chambers comprising an inlet chamber and an outlet chamber, means to supply fuel to the inlet chamber, means to deliver fuel from the outlet chamber to a point of use, the fuel reservoir member chambers also including a bypass chamber, means interconnecting the bypass chamber with the outlet chamber; the fuel pump also comprising pump means interconnecting the inlet chamber and the outlet chamber and adapted to suck fuel from the fuel supply means into the inlet chamber, through the pump means, out the outlet chamber, and to the fuel delivery means; the bypass chamber and the pump means providing two substantially separate paths of fuel flow in the fuel reservoir member, bypass plunger means normally closing off the flow of fuel through the bypass chamber one of the substantially separate paths including the fuel supply means and the fuel delivery means when the bypass plunger means is closed, the second of the substantially separate paths including the bypass chamber when the bypass plunger means is open, and all of the chambers and the interconnecting means therebetween being configured so as to create turbulence in the flow of any fuel supplied to the outlet chamber by the pump means and bypassed through the bypass chamber and the interconnecting means.

  20. Requirements and guidelines for NSLS experimental beam line vacuum systems: Revision A

    SciTech Connect

    Foerster, C.; Halama, H.; Thomlinson, W.

    1986-10-01

    Requirements are provided for NSLS beam line front ends and vacuum interlocks. Guidelines are provided for UHV beam line vacuum systems, including materials, vacuum hardware (pumps, valves, and flanges), acoustic delay lines and beam line fast valves, instrumentation, fabrication and testing, and the NSLS cleaning facility. Also discussed are the design review for experimenters' equipment that would be connected to the NSLS and acceptance tests for any beam line to be connected with the ring vacuum. Also appended are a description of the acoustic delay line as well as the NSLS vacuum standards and NSLS procedures. (LEW)

  1. Working in a Vacuum

    ERIC Educational Resources Information Center

    Rathey, Allen

    2005-01-01

    In this article, the author discusses several myths about vacuum cleaners and offers tips on evaluating and purchasing this essential maintenance tool. These myths are: (1) Amps mean performance; (2) Everyone needs high-efficiency particulate air (HEPA): (3) Picking up a "bowling ball" shows cleaning power; (4) All vacuum bags are the same; (5)…

  2. Pump room level, looking west in the service bay area. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Pump room level, looking west in the service bay area. Cable trays and two ventilation fans (part of the evaporative-cooling system) are visible at right. The vacuum pump is in the center in front of a concrete partition, and a water discharge pipe is visible beyond the partition at left - Wellton-Mohawk Irrigation System, Pumping Plant No. 1, Bounded by Gila River & Union Pacific Railroad, Wellton, Yuma County, AZ

  3. ELETTRA vacuum system

    NASA Astrophysics Data System (ADS)

    Bernardini, M.

    1991-08-01

    A status report of the vacuum system of ELETTRA, the 2 GeV, 400 mA light source under construction in Trieste, will be described. The Vacuum project, presented at ``Synchrotron Radiation Vacuum Workshop'' at Riken (Japan 22-24 March 1990) and more recently at EVC-2, the European Vacuum Conference at Trieste (Italy 21-26 May 1990), is now in the phase of testing a prototype sector, which is 1/24 of the ring circumference. Details and some technological aspects of the fabrication will be reviewed together with the vacuum performances. Results of laboratory experiments on components, standard or not, allowed us to finalize the main choices in light of the general philosophy of the project and will be properly summarized.

  4. Microfabricated triggered vacuum switch

    DOEpatents

    Roesler, Alexander W.; Schare, Joshua M.; Bunch, Kyle

    2010-05-11

    A microfabricated vacuum switch is disclosed which includes a substrate upon which an anode, cathode and trigger electrode are located. A cover is sealed over the substrate under vacuum to complete the vacuum switch. In some embodiments of the present invention, a metal cover can be used in place of the trigger electrode on the substrate. Materials used for the vacuum switch are compatible with high vacuum, relatively high temperature processing. These materials include molybdenum, niobium, copper, tungsten, aluminum and alloys thereof for the anode and cathode. Carbon in the form of graphitic carbon, a diamond-like material, or carbon nanotubes can be used in the trigger electrode. Channels can be optionally formed in the substrate to mitigate against surface breakdown.

  5. Cervical spine annulus vacuum.

    PubMed

    Bohrer, S P; Chen, Y M

    1988-01-01

    Thirty-eight annulus vacuums in 27 patients were analyzed with regard to location, configuration, and associated vertebral abnormalities such as degenerative changes, absent and compressed anterosuperior vertebral body corners, and annulus calcification. It is concluded that most annulus vacuums are a degenerative phenomenon at the attachment of the annulus to bone. These vacuums may be associated with other degenerative changes such as osteophytes and annulus calcification. Vacuums have a strong association with compressed anterosuperior corners. These deformed corners are thought to be early osteophytes and may be related to previous trauma, a vertebra with an absent corner, and/or normal motion. Small annulus vacuums adjacent to vertebral corners with a normal appearance are more likely to result from acute trauma.

  6. Applications of vacuum technology to novel accelerator problems

    SciTech Connect

    Garwin, E.L.

    1983-01-01

    Vacuum requirements for electron storage rings are most demanding to fulfill, due to the presence of gas desorption caused by large quantities of synchrotron radiation, the very limited area accessible for pumping ports, the need for 10/sup -9/ torr pressures in the ring, and for pressures a decade lower in the interaction regions. Design features of a wide variety of distributed ion sublimation pumps (DIP) developed at SLAC to meet these requirements are discussed, as well as NEG (non-evaporable getter) pumps tested for use in the Large Electron Positron Collider at CERN. Application of DIP to much higher pressures in electron damping rings for the Stanford Linear Collider are discussed.

  7. Vacuum and the electron tube industry

    NASA Astrophysics Data System (ADS)

    Redhead, P. A.

    2005-07-01

    The electron tube industry started with the patenting of the thermionic diode by John Ambrose Fleming in 1904. The vacuum technology used by the infant tube industry was copied from the existing incandescent lamp industry. The growing demands for electron tubes for the military in the first world war led to major improvements in pumps and processing methods. By the 1920s, mass production methods were developing to satisfy the demands for receiving tubes by the burgeoning radio industry. Further expansion in the 1930s and 1940s resulted in improvements in automatic equipment for pumping vacuum tubes leading to the massive production rates of electron tubes in the second world war and the following two decades. The demand for radar during the war resulted in the development of techniques for large-scale production of microwave tubes and CRTs, the latter technology being put to good use later in TV picture tube production. The commercial introduction of the transistor ended the massive demand for receiving tubes. This review concentrates on the vacuum technology developed for receiving tube production.

  8. Refraction of light by light in vacuum

    NASA Astrophysics Data System (ADS)

    Sarazin, Xavier; Couchot, François; Djannati-Ataï, Arache; Guilbaud, Olivier; Kazamias, Sophie; Pittman, Moana; Urban, Marcel

    2016-01-01

    In very intense electromagnetic fields, the vacuum refractive index is expected to be modified due to nonlinear quantum electrodynamics (QED) properties. Several experimental tests using high intensity lasers have been proposed to observe electromagnetic nonlinearities in vacuum, such as the diffraction or the reflection of intense laser pulses. We propose a new approach which consists in observing the refraction, i.e. the rotation of the waveplanes of a probe laser pulse crossing a transverse vacuum index gradient. The latter is produced by the interaction of two very intense and ultra short laser pulses, used as pump pulses. At the maximum of the index gradient, the refraction angle of the probe pulse is estimated to be 0.2 × (w0/10 μm)-3 × I/1J prad, where I is the total energy of the two pump pulses and w0 is the minimum waist (fwhm) at the interaction area. Assuming the most intense laser pulses attainable by the LASERIX facility (I = 25 J, 30 fs fwhm duration, 800 nm central wavelength) and assuming a minimum waist of w = 10 μm (fwhm) (corresponding to an intensity of the order of 1021 W/cm2), the expected maximum refraction angle is about 5 prad. An experimental setup, using a Sagnac interferometer, is proposed to perform this measurement.

  9. Contamination Effects of Getter Ion and Titanium Sublimation Pumped Systems on Optical Surfaces

    NASA Technical Reports Server (NTRS)

    Visentine, James T.; Richmond, Robert G.

    1973-01-01

    Previous studies have indicated that ultraclean vacuum can be produced when titanium sublimation pumps are used in conjunction with getter-ion pumps. Experiments are described in which the degrees of cleanliness of a typical getter-ion, titanium sublimation-pumped system were monitored by measuring the effects of surface contamination on the reflectance of evaporated vacuum ultraviolet mirrors. Results are presented which indicate that severe reflectance losses occurred when startup of a getter-ion pump was initiated at too high a chamber pressure. Significant reflectance losses also occurred as a result of titanium sublimation-pump operation. These data are reviewed and recommendations for improved system performance are presented.

  10. Housing protects laser in vacuum

    NASA Technical Reports Server (NTRS)

    Canali, V. G.

    1978-01-01

    Airtight housing encloses laser for easy alinement and operation in high-vacuum chamber. Beam is transmitted through window into vacuum chamber. Flexible line runs through vacuum chamber to outside, maintaining laser enclosure at atmospheric pressure.

  11. Semipermanent sealing of leaks in high vacuum systems

    NASA Technical Reports Server (NTRS)

    Christian, J. D.; Gilbreath, W. P.

    1974-01-01

    Silicone-rubber adhesive is applied externally to seal hair-line cracks in sections of high vacuum system while system is partially evacuated. No pretreatment of surface is required since adhesive will be drawn into crack while diffusion or ion pump is off.

  12. Evaluation of performance parameters of indigenously developed roots pumping system

    NASA Astrophysics Data System (ADS)

    Maqsood, M.; Usman, A.; Bodla, M. F.; Ali, J.

    2016-08-01

    Roots pumping systems are widely used in industries to generate vacuum with high pumping speed. In the present work, the performance parameters of indigenously developed Roots pumping system have been studied. The performance parameters being studied are the ultimate pressure, working temperature, compression ratio and pumping speed. Ultimate pressure of the Roots pump after continuous running of eight hours is found to be 1.1x10-3 mbar. The most important parameter of the roots pump is the zero-gas flow compression Ratio (Ko) which is found to be 18 for the pumping system under study. Efficiency of Roots pump is found to be 76% which is in good agreement as reported in the literature.

  13. Design Criteria for Vacuum Wastewater Transfer Systems in Advanced Base Applications

    DTIC Science & Technology

    1979-05-01

    System Performance ... ..... 23 Air Admisiion and Control Criteria ..... ............. ... 24 Vacuum Systel-s in Network Applications...States via Vacuum Technology, Inc., in 1970 (Ref 5 ). A number of large-scale operational installations have been made in housing developments in the...lift requirements 4. Sizing the vacuum discharge pumps without recognizing their functions 5 . High potential for solids and grease deposition in the

  14. APPARATUS FOR VACUUM DEPOSITION OF METALS

    DOEpatents

    Milleron, N.

    1962-03-13

    An apparatus and a method are described for continuous vacuum deposition of metals for metallic coatings, for ultra-high vacuum work, for purification of metals, for maintaining high-density electron currents, and for other uses. The apparatus comprises an externally cooled feeder tube extending into a container and adapted to feed metal wire or strip so that it emerges in a generally vertical position therein. The tube also provides shielding from the heat produced by an electron beam therein focused to impinge from a vertical direction upon the tip of the emerging wire. By proper control of the wire feed, coolant feed, and electron beam intensity, a molten ball of metal forms upon the emerging tip and remains self-supported thereon by the interaction of various forces. The metal is vaporized and travels in a line of sight direction, while additional wire is fed from the tube, so that the size of the molten ball remains constant. In the preferred embodiments, the wire is selected from a number of gettering metals and is degassed by electrical resistance in an adjacent chamber which is also partially evacuated. The wire is then fed through the feed tube into the electron beam and vaporizes and adsorbs gases to provide pumping action while being continuously deposited upon surfaces within the chamber. Ion pump electrodes may also be provided within line of sight of the vaporizing metal source to enhance the pumping action. (AEC)

  15. Electrokinetic pump

    DOEpatents

    Hencken, Kenneth R.; Sartor, George B.

    2004-08-03

    An electrokinetic pump in which the porous dielectric medium of conventional electrokinetic pumps is replaced by a patterned microstructure. The patterned microstructure is fabricated by lithographic patterning and etching of a substrate and is formed by features arranged so as to create an array of microchannels. The microchannels have dimensions on the order of the pore spacing in a conventional porous dielectric medium. Embedded unitary electrodes are vapor deposited on either end of the channel structure to provide the electric field necessary for electroosmotic flow.

  16. The water outgassing rate of internal surfaces of vacuum systems

    NASA Astrophysics Data System (ADS)

    Rozanov, L. N.

    2016-07-01

    On the basis of experimental adsorption isotherm the ratio between the real and geometrical surfaces was calculated and the amount of gas required to form a monolayer was defined. Simultaneous usage of Henry and Frendlih equations allowed to determine the dependence of the heat of adsorption on the logarithm of the absorbed gas amount A mathematical model of pumping of the vacuum systems with adsorbing walls is presented. This model uses the parameters of the vacuum system and the dependence of the adsorption heat on the amount of the adsorbed gas .The conditions of the existence of regular pumping regime are discussed. The structure database vacuum adsorption properties of materials was proposed. The experimental data on the determination of the adsorption outgassing rate were released.

  17. Systems and methods for analyzing liquids under vacuum

    DOEpatents

    Yu, Xiao-Ying; Yang, Li; Cowin, James P.; Iedema, Martin J.; Zhu, Zihua

    2013-10-15

    Systems and methods for supporting a liquid against a vacuum pressure in a chamber can enable analysis of the liquid surface using vacuum-based chemical analysis instruments. No electrical or fluid connections are required to pass through the chamber walls. The systems can include a reservoir, a pump, and a liquid flow path. The reservoir contains a liquid-phase sample. The pump drives flow of the sample from the reservoir, through the liquid flow path, and back to the reservoir. The flow of the sample is not substantially driven by a differential between pressures inside and outside of the liquid flow path. An aperture in the liquid flow path exposes a stable portion of the liquid-phase sample to the vacuum pressure within the chamber. The radius, or size, of the aperture is less than or equal to a critical value required to support a meniscus of the liquid-phase sample by surface tension.

  18. Custom Unit Pump Development for the EVA PLSS

    NASA Technical Reports Server (NTRS)

    Schuller, Michael; Kurwitz, Cable; Little, Frank; Oinuma, Ryoji; Larsen, Ben; Goldman, Jeff; Reinis, Filip; Trevino, Luis

    2010-01-01

    This paper describes the effort by the Texas Engineering Experiment Station (TEES) and Honeywell for NASA to design and test a pre-flight prototype pump for use in the Extra-vehicular activity (EVA) portable life support subsystem (PLSS). Major design decisions were driven by the need to reduce the pump s mass, power, and volume compared to the existing PLSS pump. In addition, the pump must accommodate a much wider range of abnormal conditions than the existing pump, including vapor/gas bubbles and increased pressure drop when employed to cool two suits simultaneously. A positive displacement, external gear type pump was selected because it offers the most compact and highest efficiency solution over the required range of flow rates and pressure drops. An additional benefit of selecting a gear pump design is that it is self priming and capable of ingesting non-condensable gas without becoming air locked. The chosen pump design consists of a 28 V DC, brushless, seal-less, permanent magnet motor driven, external gear pump that utilizes a Honeywell development that eliminates the need for magnetic coupling. The pump design was based on existing Honeywell designs, but incorporated features specifically for the PLSS application, including all of the key features of the flight pump. Testing at TEES verified that the pump meets the design requirements for range of flow rates, pressure drop, power consumption, working fluid temperature, operating time, gas ingestion, and restart capability under both ambient and vacuum conditions. The pump operated at 40 to 240 lbm/hr flow rate, 35 to 100 oF pump temperature, and 5 to 10 psid pressure rise. Power consumption of the pump controller at the nominal operating point in both ambient and vacuum conditions was 9.5 W, which was less than the 12 W predicted. Gas ingestion capabilities were tested by injecting 100 cc of air into the fluid line; the pump operated normally throughout this test.

  19. Thermophoretic vacuum wand

    DOEpatents

    Klebanoff, Leonard Elliott; Rader, Daniel John

    2001-01-01

    A thermophoretic vacuum wand that is particularly suited for transporting articles in a cleanroom environment so that potential particle contaminants in the air do not become adhered to the surface of the article is described. The wand includes a housing having a platen with a front surface with suction port(s) through the platen; a vacuum source for applying a negative pressure to the suction port(s); and heating device for the object. Heating the article when it is held by the vacuum wand affords thermophoretic protection that effectively prevents particles in the air from depositing onto the article.

  20. Thermophoretic vacuum wand

    DOEpatents

    Klebanoff, Leonard Elliott; Rader, Daniel John

    2000-01-01

    A thermophoretic vacuum wand that is particularly suited for transporting articles in a cleanroom environment so that potential particle contaminants in the air do not become adhered to the surface of the article is described. The wand includes a housing having a platen with a front surface with suction port(s) through the platen; a vacuum source for applying a negative pressure to the suction port(s); and heating device for the object. Heating the article when it is held by the vacuum wand affords thermophoretic protection that effectively prevents particles in the air from depositing onto the article.

  1. Upgrade of Vacuum Control System on EAST

    NASA Astrophysics Data System (ADS)

    Chen, Y.; Zhang, Y.; Yang, D. W.; Wang, L.; Hu, J. S.; Li, J. H.; Wu, J. H.; Wang, X. M.; EAST vacuum Group

    Experimental Advanced Superconducting Tokamak (EAST) is the first whole superconducting tokamak with divertor configuration in the world [3]. Vacuum system is one of the most important sub-systems of Tokmak device. Therefore, a stable and reliable control system for vacuum operation is required essentially during the plasma discharges. The vacuum control system (VCS) was built preliminarily in 2006. As the new requirements for the vacuum operation is proposed, it is developed and expanded continually. At present the control system has consisted of gas sub-system, pump sub-system, measurement sub-system, wall conditioning sub-system, operator workstation, monitor workstation, database and web publish platform. Comparing to the preliminary one, the whole VCS have been restored and expanded except for reserving the PLCs hardware on the basic level. This paper will present the improvement on the VCS of 2006 and the advantages of the upgrade version, Meanwhile, the new techniques of AJAX (Asynchronous JavaScript and XML) and SVG (Scalable Vector Graphics) will be introduced, which is applied to the user interface at the first time.

  2. Collapse of vacuum bubbles in a vacuum

    SciTech Connect

    Ng, Kin-Wang; Wang, Shang-Yung

    2011-02-15

    We revisit the dynamics of a false vacuum bubble in a background de Sitter spacetime. We find that there exists a large parameter space that allows the bubble to collapse into a black hole or to form a wormhole. This may have interesting implications for the creation of a baby universe in the laboratory, the string landscape where the bubble nucleation takes place among a plenitude of metastable vacua, and the inflationary physics.

  3. MMS Observatory Thermal Vacuum Results Contamination Summary

    NASA Technical Reports Server (NTRS)

    Rosecrans, Glenn P.; Errigo, Therese; Brieda, Lubos

    2014-01-01

    The MMS mission is a constellation of 4 observatories designed to investigate the fundamental plasma physics of reconnection in the Earths magnetosphere. Each spacecraft has undergone extensive environmental testing to prepare it for its minimum 2 year mission. The various instrument suites measure electric and magnetic fields, energetic particles, and plasma composition. Thermal vacuum testing was conducted at the Naval Research Laboratory (NRL) in their Big Blue vacuum chamber. The individual spacecraft were tested and enclosed in a cryopanel enclosure called a Hamster cage. Specific contamination control validations were actively monitored by several QCMs, a facility RGA, and at times, with 16 Ion Gauges. Each spacecraft underwent a bakeout phase, followed by 4 thermal cycles. Unique aspects of the TV environment included slow pump downs with represses, thruster firings, Helium identification, and monitoring pressure spikes with Ion gauges. Various data from these TV tests will be shown along with lessons learned.

  4. Vacuum mechatronics first international workshop

    SciTech Connect

    Belinski, S.E.; Shirazi, M.; Hackwood, S.; Beni, G. )

    1989-01-01

    This report contains papers on the following topics: proposed epitaxial thin film growth in the ultra-vacuum of space; particle monitoring and control in vacuum processing equipment; electrostatic dust collector for use in vacuum systems; materials evaluation of an electrically noisy vacuum slip ring assembly; an overview of lubrication and associated materials for vacuum service; the usage of lubricants in a vacuum environment; guidelines and practical applications for lubrication in vacuum; recent development in leak detector and calibrator designs; the durability of ballscrews for ultrahigh vacuum; vacuum-compatible robot for self-contained manufacturing systems; the design, fabrication, and assembly of an advanced vacuum robotics system for space payload calibration; design criteria for mechanisms used in space; and concepts and requirements for semiconductor multiprocess integration in vacuum. These papers are indexed separately elsewhere.

  5. The classical vacuum

    NASA Astrophysics Data System (ADS)

    Boyer, T. H.

    1985-08-01

    The history of vacuum concepts is reviewed, noting that no way is known to physically produce a true void. Even at absolute zero, a pattern of electromagnetic wave fluctuations are still present. The fluctuations are called zero-point radiation (ZPR). To be invariant to Lorentz transformation, ZPR has a spectral intensity proportional to the cube of each frequency. ZPR does not change in response to compression and produces a force between objects that is inversely proportional to the 4th power of the separation distance. The ZPR scale value has been measured to be one-half of the Planck constant, and is the measure of the energy of a harmonic oscillator, such as the electron, in a vacuum. Finally, since gravitational accelerations always occur in the physical space, a minimum thermal radiation can also be found for the vacuum, implying that a fixed relationship exists between thermal radiation and the classical vacuum.

  6. Vacuum Camera Cooler

    NASA Technical Reports Server (NTRS)

    Laugen, Geoffrey A.

    2011-01-01

    Acquiring cheap, moving video was impossible in a vacuum environment, due to camera overheating. This overheating is brought on by the lack of cooling media in vacuum. A water-jacketed camera cooler enclosure machined and assembled from copper plate and tube has been developed. The camera cooler (see figure) is cup-shaped and cooled by circulating water or nitrogen gas through copper tubing. The camera, a store-bought "spy type," is not designed to work in a vacuum. With some modifications the unit can be thermally connected when mounted in the cup portion of the camera cooler. The thermal conductivity is provided by copper tape between parts of the camera and the cooled enclosure. During initial testing of the demonstration unit, the camera cooler kept the CPU (central processing unit) of this video camera at operating temperature. This development allowed video recording of an in-progress test, within a vacuum environment.

  7. Infrared detector Dewars - Increased LN2 hold time and vacuum jacket life spans

    NASA Technical Reports Server (NTRS)

    Jennings, D. E.; Boyd, W. J.; Blass, W. E.

    1976-01-01

    IR detector Dewars commonly suffer from shorter than desired LN2 hold times and insulation jacket vacuum corruption over relatively short time periods. In an attempt to solve this problem for a 9144 detector Dewar, small 1 liter/s appendage ion pumps were selected for continuous pumping of the vacuum jackets. This procedure extended LN2 hold times from 20 to 60 h and virtually eliminated vacuum jacket corruption. Thus the detector systems are usable continuously over periods of 6 months or more.

  8. 18. Electrically driven pumps in Armory Street Pump House. Pumps ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    18. Electrically driven pumps in Armory Street Pump House. Pumps in background formerly drew water from the clear well. They went out of service when use of the beds was discontinued. Pumps in the foreground provide high pressure water to Hamden. - Lake Whitney Water Filtration Plant, Armory Street Pumphouse, North side of Armory Street between Edgehill Road & Whitney Avenue, Hamden, New Haven County, CT

  9. Ultra-high vacuum photoelectron linear accelerator

    DOEpatents

    Yu, David U.L.; Luo, Yan

    2013-07-16

    An rf linear accelerator for producing an electron beam. The outer wall of the rf cavity of said linear accelerator being perforated to allow gas inside said rf cavity to flow to a pressure chamber surrounding said rf cavity and having means of ultra high vacuum pumping of the cathode of said rf linear accelerator. Said rf linear accelerator is used to accelerate polarized or unpolarized electrons produced by a photocathode, or to accelerate thermally heated electrons produced by a thermionic cathode, or to accelerate rf heated field emission electrons produced by a field emission cathode.

  10. A NORMETEX MODEL 15 M3/HR WATER VAPOR PUMPING TEST

    SciTech Connect

    Klein, J.; Fowley, M.; Steeper, T.

    2010-12-20

    Tests were performed using a Model 15 m{sup 3}/hr Normetex vacuum pump to determine if pump performance degraded after pumping a humid gas stream. An air feed stream containing 30% water vapor was introduced into the pump for 365 hours with the outlet pressure of the pump near the condensation conditions of the water. Performance of the pump was tested before and after the water vapor pumping test and indicated no loss in performance of the pump. The pump also appeared to tolerate small amounts of condensed water of short duration without increased noise, vibration, or other adverse indications. The Normetex pump was backed by a dual-head diaphragm pump which was affected by the condensation of water and produced some drift in operating conditions during the test.

  11. Characterization of the CEBAF 100 kV DC GaAs Photoelectron Gun Vacuum System

    SciTech Connect

    Stutzman, M L; Adderley, P; Brittian, J; Clark, J; Grames, J; Hansknecht, J; Myneni, G R; Poelker, M

    2007-05-01

    A vacuum system with pressure in the low ultra-high vacuum (UHV) range is essential for long photocathode lifetimes in DC high voltage GaAs photoguns. A discrepancy between predicted and measured base pressure in the CEBAF photoguns motivated this study of outgassing rates of three 304 stainless steel chambers with different pretreatments and pump speed measurements of non-evaporable getter (NEG) pumps. Outgassing rates were measured using two independent techniques. Lower outgassing rates were achieved by electropolishing and vacuum firing the chamber. The second part of the paper describes NEG pump speed measurements as a function of pressure through the lower part of the UHV range. Measured NEG pump speed is high at pressures above 5×10-11 Torr, but may decrease at lower pressures depending on the interpretation of the data. The final section investigates the pump speed of a locally produced NEG coating applied to the vacuum chamber walls. These studies represent the first detailed vacuum measurements of CEBAF photogun vacuum chambers.

  12. Gas flow analysis during thermal vacuum test of a spacecraft.

    NASA Technical Reports Server (NTRS)

    Scialdone, J. J.

    1973-01-01

    The pressures indicated by two tubulated ionization gages, one pointing to a spinning spacecraft undergoing thermal vacuum test and the other the walls of the chamber, have been used in a computer program to calculate important parameters of flow kinetics in the vacuum chamber. These parameters calculated as a function of time are: the self-contamination of the spacecraft (defined as the return of outgassed molecules on its critical surfaces either in orbit or while undergoing vacuum test); the spacecraft outgassing including leaks from sealed compartments; and the gas pumping performance of the vacuum chamber. The test indicated the feasibility of this type of evaluation and the improvements in instrumentations and arrangements needed for future tests.

  13. Space simulation ultimate pressure lowered two decades by removal of diffusion pump oil contaminants during operation

    NASA Technical Reports Server (NTRS)

    Buggele, A. E.

    1973-01-01

    The complex problem why large space simulation chambers do not realize the true ultimate vacuum was investigated. Some contaminating factors affecting diffusion pump performance have been identified and some advances in vacuum/distillation/fractionation technology have been achieved which resulted in a two decade or more lower ultimate pressure. Data are presented to show the overall or individual contaminating effect of commonly used phthalate ester plasticizers of 390 to 530 molecular weight on diffusion pump performance. Methods for removing contaminants from diffusion pump silicone oil during operation and reclaiming contaminated oil by high vacuum molecular distillation are described.

  14. Sensitive Ion Pump Current Monitoring Using an In-House Built Ion Pump Power Supply

    SciTech Connect

    Hansknecht, J.; Adderley, P.; Stutzman, M. L.; Poelker, M.

    2009-08-04

    Ion pumps are common vacuum pumps on DC high voltage photoguns and baked-accelerator beamlines. Commercial ion pump power supplies provide a measure of the electrical current drawn by the pump, but typically have resolution to only {approx}0.1 uA, which corresponds to pressure {approx}10{sup -9} Torr, a value considerably higher than the minimum pressure required by photoguns and nearby beamline. This submission describes a very sensitive in-house-built ion pump power supply with current monitoring capability good to less than 1 nA, and corresponding pressure in the low-minus;10{sup -11} Torr range. Besides providing 'free' pressure monitoring on a scale equivalent to the best available commercial pressure gauges, the ion pump power supply also serves as a sensitive diagnostic for detecting field emission from the photogun cathode electrode and bad electron beam orbits that could diminish photogun operating lifetime. Since its inception, this ion pump power supply has become an invaluable tool for operating the CEBAF polarized electron source. It is also a very useful low-cost diagnostic for ultrahigh vacuum studies in the laboratory.

  15. Solar Pump

    NASA Technical Reports Server (NTRS)

    Pique, Charles

    1987-01-01

    Proposed pump moves liquid by action of bubbles formed by heat of sun. Tube of liquid having boiling point of 100 to 200 degrees F placed at focal axis of cylindrical reflector. Concentrated sunlight boils liquid at focus, and bubbles of vapor rise in tube, carrying liquid along with them. Pressure difference in hot tube sufficient to produce flow in large loop. Used with conventional flat solar heating panel in completely solar-powered heat-storage system.

  16. Heat pump

    SciTech Connect

    Apte, A.J.

    1982-11-30

    A single working fluid heat pump system having a turbocompressor with a first fluid input for the turbine and a second fluid input for the compressor, and a single output volute or mixing chamber for combining the working fluid output flows of the turbine and the compressor. The system provides for higher efficiency than single fluid systems whose turbine and compressor are provided with separate output volutes.

  17. Electric field divertor plasma pump

    DOEpatents

    Schaffer, M.J.

    1994-10-04

    An electric field plasma pump includes a toroidal ring bias electrode positioned near the divertor strike point of a poloidal divertor of a tokamak, or similar plasma-confining apparatus. For optimum plasma pumping, the separatrix of the poloidal divertor contacts the ring electrode, which then also acts as a divertor plate. A plenum or other duct near the electrode includes an entrance aperture open to receive electrically-driven plasma. The electrode is insulated laterally with insulators, one of which is positioned opposite the electrode at the entrance aperture. An electric field E is established between the ring electrode and a vacuum vessel wall, with the polarity of the bias applied to the electrode being relative to the vessel wall selected such that the resultant electric field E interacts with the magnetic field B already existing in the tokamak to create an E [times] B/B[sup 2] drift velocity that drives plasma into the entrance aperture. The pumped plasma flow into the entrance aperture is insensitive to variations, intentional or otherwise, of the pump and divertor geometry. Pressure buildups in the plenum or duct connected to the entrance aperture in excess of 10 mtorr are achievable. 11 figs.

  18. Electric field divertor plasma pump

    DOEpatents

    Schaffer, Michael J.

    1994-01-01

    An electric field plasma pump includes a toroidal ring bias electrode (56) positioned near the divertor strike point of a poloidal divertor of a tokamak (20), or similar plasma-confining apparatus. For optimum plasma pumping, the separatrix (40) of the poloidal divertor contacts the ring electrode (56), which then also acts as a divertor plate. A plenum (54) or other duct near the electrode (56) includes an entrance aperture open to receive electrically-driven plasma. The electrode (56) is insulated laterally with insulators (63,64), one of which (64) is positioned opposite the electrode at the entrance aperture. An electric field E is established between the ring electrode (56) and a vacuum vessel wall (22), with the polarity of the bias applied to the electrode being relative to the vessel wall selected such that the resultant electric field E interacts with the magnetic field B already existing in the tokamak to create an E.times.B/B.sup.2 drift velocity that drives plasma into the entrance aperture. The pumped plasma flow into the entrance aperture is insensitive to variations, intentional or otherwise, of the pump and divertor geometry. Pressure buildups in the plenum or duct connected to the entrance aperture in excess of 10 mtorr are achievable.

  19. Energy saving pump and pumping system

    SciTech Connect

    Chang, K.C.

    1983-08-02

    A centrifugal pump and a pumping system are disclosed that recover hydraulic energy in response to flow capacity reduction and spontaneously provide a recirculating flow at low capacities when pump cooling is needed. From a upstream source the fluid is guided by two suction lines to two parallel pumping mechanisms housed by a common discharge casing. Said pumping mechanisms have a combined hydraulic characteristic that the first pumping mechanism will force a reverse flow through the second pumping mechanism, when pump discharge is reduced by the system below a certain low flow rate. The reverse flow will then return to the upstream fluid source through a suction line. The pump is the protected from overheating by a circulating flow at low flow capacities. At the same time, said reverse flow generates a turbine action on the second pumping mechanism and transmits the contained hydraulic energy back to the rotor and thereby results in power saving at low flow capacities.

  20. Improving Vacuum Cleaners

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Under a Space Act Agreement between the Kirby company and Lewis Research Center, NASA technology was applied to a commercial vacuum cleaner product line. Kirby engineers were interested in advanced operational concepts, such as particle flow behavior and vibration, critical factors to improve vacuum cleaner performance. An evaluation of the company 1994 home care system, the Kirby G4, led to the refinement of the new G5 and future models. Under the cooperative agreement, Kirby had access to Lewis' holography equipment, which added insight into how long a vacuum cleaner fan would perform, as well as advanced computer software that can simulate the flow of air through fans. The collaboration resulted in several successes including fan blade redesign and continuing dialogue on how to improve air-flow traits in various nozzle designs.

  1. Proposed Physics Experiments for Laser-Driven Electron Linear Acceleration in a Dielectric Loaded Vacuum, Final Report

    SciTech Connect

    Byer, Robert L.

    2016-07-08

    This final report summarizes the last three years of research on the development of advanced linear electron accelerators that utilize dielectric wave-guide vacuum channels pumped by high energy laser fields to accelerate beams of electrons.

  2. DISK PUMP FEASIBILITY INVESTIGATION,

    DTIC Science & Technology

    The disk pump was investigated at the Air Force Rocket Propulsion Laboratory (AFRPL) to determine the feasibility of using a novel viscous pumping... pump primarily for application as an inducer. The disk pump differs drastically from conventional pumps because of the following major factors: (1) The...The pump inlet relative velocity is equal only to the through flow velocity between the disks. Therefore, there is good indication that the disk pump will

  3. Simulation studies of vacuum system for Indus-2

    NASA Astrophysics Data System (ADS)

    Shukla, S. K.; Kotaiah, S.

    2008-05-01

    Due to eight fold symmetry of lattice, the 172.4 meters circumference of Indus-2 was divided into eight unit cells. The location of vacuum pumps was restricted by location of more important components like magnets, beam diagnostic components etc. The minimum permissible beam aperture, restricted by apertures of magnets, rendered the vacuum envelope highly conductance limited. Main sources of gas loads viz the outgassing and the photon induced desorption (PID) were also highly location specific, because of location of photon absorbers, and the specific nature of vacuum components. Therefore, the computer simulation of a unit cell was important to have a feel for ultimate results obtained by a particular configuration of pump installation. The vacuum system for a unit cell was studied using electrical equivalent network for the vacuum system. The entire circuit was analyzed by using commercial software used for electronics circuit analysis. Since the synchrotron radiation leads to cleaning effect and the PID yield reduces with accumulated dose of beam current, system's behaviour with beam current was also studied by using computer program obtained from BESSY Berlin. This provided an estimate of dose necessary for achieving the specified operation of UHV system for Indus-2. The calculations also helped in optimizing the initial cleaning of chambers by glow discharge cleaning etc. This paper presents the results obtained by computer simulations of a unit cell of Indus-2, carried out by both the methods.

  4. Superoleophobicity under vacuum

    NASA Astrophysics Data System (ADS)

    Liu, Xinjie; Wang, Xiaolong; Liang, Yongmin; Bell, Steven E. J.; Liu, Weimin; Zhou, Feng

    2011-05-01

    By using superoleophobic alumina and low vapor pressure oils we have been able to study wetting behavior at high vacuum. Here, we show that a superoleophobic state can exist for some probe liquids, even under high vacuum. However, with other liquids the surfaces are only superoloephobic because air is trapped beneath the droplet and the contact angle decreases dramatically (150°-120°) if this air is removed. These observations open up the possibility of designing materials which fully exploit the potential of physically trapped air to achieve extreme oleophobicity and/or hydrophobicity.

  5. Electrostatic Levitator Vacuum Chamber

    NASA Technical Reports Server (NTRS)

    1998-01-01

    Optical ports ring the Electrostatic Levitator (ESL) vacuum chamber to admit light from the heating laser (beam passes through the window at left), positioning lasers (one port is at center), and lamps to allow diagnostic instruments to view the sample. The ESL uses static electricity to suspend an object (about 2-3 mm in diameter) inside a vacuum chamber while a laser heats the sample until it melts. This lets scientists record a wide range of physical properties without the sample contacting the container or any instruments, conditions that would alter the readings. The Electrostatic Levitator is one of several tools used in NASA's microgravity materials science program.

  6. DYNAVAC: a transient-vacuum-network analysis code

    SciTech Connect

    Deis, G.A.

    1980-07-08

    This report discusses the structure and use of the program DYNAVAC, a new transient-vacuum-network analysis code implemented on the NMFECC CDC-7600 computer. DYNAVAC solves for the transient pressures in a network of up to twenty lumped volumes, interconnected in any configuration by specified conductances. Each volume can have an internal gas source, a pumping speed, and any initial pressure. The gas-source rates can vary with time in any piecewise-linear manner, and up to twenty different time variations can be included in a single problem. In addition, the pumping speed in each volume can vary with the total gas pumped in the volume, thus simulating the saturation of surface pumping. This report is intended to be both a general description and a user's manual for DYNAVAC.

  7. Well pump

    SciTech Connect

    Page, J.S.

    1983-03-08

    Well fluid pumping apparatus comprises: (A) body structure defining an upright plunger bore, (B) a plunger reciprocable in that bore, (C) the body structure also defining a chamber sidewardly offset from an axis defined by the plunger bore and communicating with the bore, and (D) valving carried by the body structure to pass intake fluid via the chamber into the plunger bore in response to stroking of the plunger in one direction in the bore, and to pass discharge fluid from the plunger bore into and from the chamber in response to stroking of the plunger in the opposite direction in the bore.

  8. Miniature thermo-electric cooled cryogenic pump

    DOEpatents

    Keville, R.F.

    1997-11-18

    A miniature thermo-electric cooled cryogenic pump is described for removing residual water molecules from an inlet sample prior to sample analysis in a mass spectroscopy system, such as ion cyclotron resonance (ICR) mass spectroscopy. The cryogenic pump is a battery operated, low power (<1.6 watts) pump with a {Delta}T=100 C characteristic. The pump operates under vacuum pressures of 5{times}10{sup {minus}4} Torr to ultra high vacuum (UHV) conditions in the range of 1{times}10{sup {minus}7} to 3{times}10{sup {minus}9} Torr and will typically remove partial pressure, 2{times}10{sup {minus}7} Torr, residual water vapor. The cryogenic pump basically consists of an inlet flange piece, a copper heat sink with a square internal bore, four two tier Peltier (TEC) chips, a copper low temperature square cross sectional tubulation, an electronic receptacle, and an exit flange piece, with the low temperature tubulation being retained in the heat sink at a bias angle of 5{degree}, and with the TECs being positioned in parallel to each other with a positive potential being applied to the top tier thereof. 2 figs.

  9. Miniature thermo-electric cooled cryogenic pump

    DOEpatents

    Keville, Robert F.

    1997-01-01

    A miniature thermo-electric cooled cryogenic pump for removing residual water molecules from an inlet sample prior to sample analysis in a mass spectroscopy system, such as ion cyclotron resonance (ICR) mass spectroscopy. The cryogenic pump is a battery operated, low power (<1.6 watts) pump with a .DELTA.T=100.degree. C. characteristic. The pump operates under vacuum pressures of 5.times.10.sup.-4 Torr to ultra high vacuum (UHV) conditions in the range of 1.times.10.sup.-7 to 3.times.10.sup.-9 Torr and will typically remove partial pressure, 2.times.10.sup.-7 Torr, residual water vapor. The cryogenic pump basically consists of an inlet flange piece, a copper heat sink with a square internal bore, four two tier Peltier (TEC) chips, a copper low temperature square cross sectional tubulation, an electronic receptacle, and an exit flange piece, with the low temperature tubulation being retained in the heat sink at a bias angle of 5.degree., and with the TECs being positioned in parallel to each other with a positive potential being applied to the top tier thereof.

  10. Interchangeability of gas detection tubes and hand pumps.

    PubMed

    Haag, W R

    2001-01-01

    Users of gas detection tubes occasionally seek the convenience of using a single hand pump with different brands of tubes, to avoid the need to carry more than one pump. Several professional organizations recommend against such interchange. However, these recommendations appear to be based on a single study of pump designs that mostly are no longer in use. The present study was undertaken to determine if current hand pumps are interchangeable. Both piston-type and bellows-type hand pumps were evaluated by comparing pump flow profiles and test gas measurements with a variety of tubes. The results demonstrate that three piston hand pumps in common use (Sensidyne/Gastec GV/100, RAE Systems LP-1200, and Matheson-Kitagawa 8104-400A) are fully interchangeable. Two bellows pumps (Draeger Accuro and MSA Kwik-Draw) also are interchangeable with each other. Mixing of bellows and piston systems is often possible, but there are enough exceptions to conclude that such practice should be discouraged because it can give inaccurate readings. It is recommended that technical standards be adopted, such as total volume and an initial pump vacuum or a pump flow curve, to assess hand pump interchangeability. When two manufacturers' pumps meet the same standard and routine leak tests are conducted, interchangeability is scientifically valid and poses no risk to the end user while offering greater convenience.

  11. Effect of preliminary vacuum plasma treatment on coating adhesion

    NASA Astrophysics Data System (ADS)

    Slabodchikov, Vladimir A.; Borisov, Dmitry P.; Kuznetsov, Vladimir M.

    2016-11-01

    The paper presents research results on the adhesion properties of Si coatings synthesized by different methods and under different conditions of preliminary vacuum ion plasma treatment of substrates with subsequent magnetron sputtering. The substrate surface was pretreated with low-energy ion beams, high-energy ion beams, gas discharge plasma, and plasma produced by a magnetron sputtering system. The vacuum conditions (pump type, pressure, etc.), the ion current density, and the bias parameters (pulse repetition frequency and duration) were varied. The research results demonstrate a considerable effect of plasma immersion ion implantation on the adhesion of Si coatings to NiTi substrates.

  12. The Instrument Test Dewar (ITD): Testing satellite instruments at 1.5 K

    NASA Technical Reports Server (NTRS)

    Milam, Laura J.

    1988-01-01

    The Instrument Test Dewar (ITD) is a cryogenic facility designed and built to test Cosmic Background Explorer (COBE) satellite instruments at 1.5 K. The facility provides a high vacuum and thermal environment with payload thermal, electrical and optical interfaces. There are two concentric vacuum spaces which are not hermitically sealed. The instrument vacuum space is 81.28 cm by 243.84 cm and is cooled by an LHe shroud. The guard vacuum space surrounds an LN2 shroud. There are two separate cryosorption pumping systems and a mechanical LHe pumping system. The data acquisition systems provide payload and housekeeping data. There have been various problems with the facility, and changes and improvements have been made to assure optimum test conditions. COBE instrument testing has been completed on structural, thermal model hardware and the protoflight units.

  13. VACUUM SEALING MEANS FOR LOW VACUUM PRESSURES

    DOEpatents

    Milleron, N.

    1962-06-12

    S>A vacuum seal is designed in which the surface tension of a thin layer of liquid metal of low vapor pressure cooperates with adjacent surfaces to preclude passages of gases across pressure differentials as low as 10/sup -8/ mm Hg. Mating contiguous surfaces composed of copper, brass, stainless steel, nickel, molybdenum, tungsten, tantalum, glass, quartz, and/or synthetic mica are disposed to provide a maximum tolerance, D, expressed by 2 gamma /P/sub 1/, where gamma is the coefflcient of the surface tension of the metal sealant selected in dynes/cm/sub 2/. Means for heating the surfaces remotely is provided where temperatures drop below about 250 deg C. A sealant consisting of an alloy of gallium, indium, and tin, among other combinations tabulated, is disposed therebetween after treating the surfaces to improve wettability, as by ultrasonic vibrations, the surfaces and sealants being selected according to the anticipated experimental conditions of use. (AEC)

  14. Pump apparatus

    SciTech Connect

    Kime, J.A.

    1987-02-17

    This patent describes a gas-oil well production system for pumping formation fluid wherein a down hole pump is provided having a barrel including a barrel fluid inlet, a barrel fluid outlet, a barrel chamber, and a plunger mounted in the barrel chamber having a plunger chamber. The plunger is reciprocally driven between an upper terminal position at the end of the plunger upstroke and a lower terminal position at the end of the plunger downstroke. The method for removing developed gaseous fluids in the formation fluid from the barrel chamber comprises: drawing formation fluid into the barrel chamber during the plunger upstroke; providing gas port means in the barrel; expelling the developed gaseous fluids from the barrel chamber through the gas port means during the occurrence of that portion of the plunger downstroke from the upper terminal position of the gas port means; and substantially blocking the gas port means and moving formation fluid into the plunger chamber during the occurrence of that portion of the plunger downstroke from below the gas port means to the lower terminal position.

  15. Optical testing cryogenic thermal vacuum facility

    NASA Technical Reports Server (NTRS)

    Dohogne, Patrick W.; Carpenter, Warren A.

    1990-01-01

    The construction of a turnkey cryogenic vacuum test facility was recently completed. The facility will be used to measure and record the surface profile of large diameter and 540 kg optics under simulated space conditions. The vacuum test chamber is a vertical stainless steel cylinder with a 3.5 diameter and a 7 m tangent length. The chamber was designed to maximize optical testing quality by minimizing the vibrations between the laser interferometer and the test specimen. This was accomplished by designing the chamber for a high natural frequency and vibration isolating the chamber. An optical test specimen is mounted on a movable presentation stage. During thermal vacuum testing, the specimen may be positioned to + or - 0.00025 cm accuracy with a fine adjustment mechanism. The chamber is evacuated by a close coupled Roots-type blower and rotary vane pump package and two cryopumps. The chamber is equipped with an optically dense gaseous nitrogen cooled thermal shroud. The thermal shroud is used to cool or warm the optical test specimen at a controlled rate. A control system is provided to automatically evacuate the chamber and cooldown the test specimen to the selected control temperature.

  16. Partial-Vacuum-Gasketed Electrochemical Corrosion Cell

    NASA Technical Reports Server (NTRS)

    Bonifas, Andrew P.; Calle, Luz M.; Hintze, Paul E.

    2006-01-01

    An electrochemical cell for making corrosion measurements has been designed to prevent or reduce crevice corrosion, which is a common source of error in prior such cells. The present cell (see figure) includes an electrolyte reservoir with O-ring-edged opening at the bottom. In preparation for a test, the reservoir, while empty, is pressed down against a horizontal specimen surface to form an O-ring seal. A purge of air or other suitable gas is begun in the reservoir, and the pressure in the reservoir is regulated to maintain a partial vacuum. While maintaining the purge and partial vacuum, and without opening the interior of the reservoir to the atmosphere, the electrolyte is pumped into the reservoir. The reservoir is then slowly lifted a short distance off the specimen. The level of the partial vacuum is chosen such that the differential pressure is just sufficient to keep the electrolyte from flowing out of the reservoir through the small O-ring/specimen gap. Electrochemical measurements are then made. Because there is no gasket (and, hence, no crevice between the specimen and the gasket), crevice corrosion is unlikely to occur.

  17. Gas injected vacuum switch

    DOEpatents

    Hardin, K. Dan

    1977-01-01

    The disclosure relates to a gas injected vacuum switch comprising a housing having an interior chamber, a conduit for evacuating the interior chamber, within the chamber an anode and a cathode spaced from the anode, and a detonator for injecting electrically conductive gas into the chamber between the anode and the cathode to provide a current path therebetween.

  18. Vacuum Kundt waves

    NASA Astrophysics Data System (ADS)

    McNutt, David; Milson, Robert; Coley, Alan

    2013-03-01

    We discuss the invariant classification of vacuum Kundt waves using the Cartan-Karlhede algorithm and determine the upper bound on the number of iterations of the Karlhede algorithm to classify the vacuum Kundt waves (Collins (1991 Class. Quantum Grav. 8 1859-69), Machado Ramos (1996 Class. Quantum Grav. 13 1589)). By choosing a particular coordinate system we partially construct the canonical coframe used in the classification to study the functional dependence of the invariants arising at each iteration of the algorithm. We provide a new upper bound, q ⩽ 4, and show that this bound is sharp by analyzing the subclass of Kundt waves with invariant count beginning with (0, 1,…) to show that the class with invariant count (0, 1, 3, 4, 4) exists. This class of vacuum Kundt waves is shown to be unique as the only set of metrics requiring the fourth covariant derivatives of the curvature. We conclude with an invariant classification of the vacuum Kundt waves using a suite of invariants.

  19. Jet Engines as High-Capacity Vacuum Pumps

    NASA Technical Reports Server (NTRS)

    Wojciechowski, C. J.

    1983-01-01

    Large diffuser operations envelope and long run times possible. Jet engine driven ejector/diffuser system combines two turbojet engines and variable-area-ratio ejector in two stages. Applications in such industrial proesses as handling corrosive fumes, evaporation of milk and fruit juices, petroleum distillation, and dehydration of blood plasma and penicillin.

  20. Development of a MEMS-Scale Turbomachinery Based Vacuum Pump

    DTIC Science & Technology

    2012-06-01

    shear stress can be specified in a commercial computational fluid dynamics code allowing slip flow to occur. This method was validated against a...stage with tip clearance is 1.0722 with power consumption of 0.4648 watts. 14. SUBJECT TERMS MEMS Turbomachinery, Computational Fluid Dynamics ...using a first order analysis, the wall shear stress can be specified in a commercial computational fluid dynamics code allowing slip flow to occur

  1. Tritium handling in vacuum systems

    SciTech Connect

    Gill, J.T.; Coffin, D.O.

    1986-10-01

    This report provides a course in Tritium handling in vacuum systems. Topics presented are: Properties of Tritium; Tritium compatibility of materials; Tritium-compatible vacuum equipment; and Tritium waste treatment.

  2. Furnace brazing under partial vacuum

    NASA Technical Reports Server (NTRS)

    Mckown, R. D.

    1979-01-01

    Brazing furnace utilizing partial-vacuum technique reduces tooling requirements and produces better bond. Benefit in that partial vacuum helps to dissociate metal oxides that inhibit metal flow and eliminates heavy tooling required to hold parts together during brazing.

  3. Heat pump processes induced by laser radiation

    NASA Technical Reports Server (NTRS)

    Garbuny, M.; Henningsen, T.

    1980-01-01

    A carbon dioxide laser system was constructed for the demonstration of heat pump processes induced by laser radiation. The system consisted of a frequency doubling stage, a gas reaction cell with its vacuum and high purity gas supply system, and provisions to measure the temperature changes by pressure, or alternatively, by density changes. The theoretical considerations for the choice of designs and components are dicussed.

  4. An experimental investigation of (UF-235)6 fission nuclear-pumped lasers

    NASA Technical Reports Server (NTRS)

    Miley, G. H.

    1979-01-01

    A UF6 handling system was designed for use in conjunction with the existing nuclear-pumped laser vacuum system at a nuclear reactor laboratory to perform the experiments described above. A modification to separate the gas fill system from the vacuum system and thus greatly reduce its volume is described as well as operating procedures for the first controlled nuclear pumping experiments with UF6 vapor contained in the laser cell.

  5. A radiation hard vacuum switch

    DOEpatents

    Boettcher, G.E.

    1988-07-19

    A vacuum switch with an isolated trigger probe which is not directly connected to the switching electrodes. The vacuum switch within the plasmatron is triggered by plasma expansion initiated by the trigger probe which travels through an opening to reach the vacuum switch elements. The plasma arc created is directed by the opening to the space between the anode and cathode of the vacuum switch to cause conduction. 3 figs.

  6. Surge-damping vacuum valve

    DOEpatents

    Bullock, Jack C.; Kelly, Benjamin E.

    1980-01-01

    A valve having a mechanism for damping out flow surges in a vacuum system which utilizes a slotted spring-loaded disk positioned adjacent the valve's vacuum port. Under flow surge conditions, the differential pressure forces the disk into sealing engagement with the vacuum port, thereby restricting the flow path to the slots in the disk damping out the flow surge.

  7. Portable vacuum object handling device

    DOEpatents

    Anderson, Gordon H.

    1983-08-09

    The disclosure relates to a portable device adapted to handle objects which are not to be touched by hand. A piston and bore wall form a vacuum chamber communicating with an adaptor sealably engageable with an object to be lifted. The piston is manually moved and set to establish vacuum. A valve is manually actuatable to apply the vacuum to lift the object.

  8. Bakeout Chamber Within Vacuum Chamber

    NASA Technical Reports Server (NTRS)

    Taylor, Daniel M.; Soules, David M.; Barengoltz, Jack B.

    1995-01-01

    Vacuum-bakeout apparatus for decontaminating and measuring outgassing from pieces of equipment constructed by mounting bakeout chamber within conventional vacuum chamber. Upgrade cost effective: fabrication and installation of bakeout chamber simple, installation performed quickly and without major changes in older vacuum chamber, and provides quantitative data on outgassing from pieces of equipment placed in bakeout chamber.

  9. Titanium alloy as a potential low radioactivation vacuum material

    SciTech Connect

    Kamiya, Junichiro Hikichi, Yusuke; Kinsho, Michikazu; Ogiwara, Norio; Fukuda, Mitsuhiro; Hamatani, Noriaki; Hatanaka, Kichiji; Kamakura, Keita; Takahisa, Keiji

    2015-05-15

    For the vacuum systems of high-intensity beam accelerators, low radioactivation materials with good vacuum characteristics and high mechanical strength are required. The titanium alloy Ti-6Al-4V was investigated as a potential low activation vacuum material with high mechanical strength for the fabrication of vacuum components, particularly the flanges of beam pipes, in the J-PARC 3 GeV synchrotron. The dose rate of Ti-6Al-4V when irradiated by a 400 MeV proton was observed to decrease more rapidly than that of stainless steel. Furthermore, the generated radioactive isotopes were nuclides with relatively short half-lives. The outgassing rate per unit area of Ti-6Al-4V was approximately 10{sup −8 }Pa m{sup 3}/s m{sup 2} after pumping for 100 h, which is the same as the typical value for stainless steel. Additionally, the hydrogen concentration in bulk Ti-6Al-4V was reduced to approximately 1 ppm by vacuum firing at 700 °C for 9 h; the mechanical strength was not reduced by this process. These results indicate that Ti-6Al-4V is a good candidate for use as a low activation vacuum material with high mechanical strength.

  10. LMFBR with booster pump in pumping loop

    DOEpatents

    Rubinstein, H.J.

    1975-10-14

    A loop coolant circulation system is described for a liquid metal fast breeder reactor (LMFBR) utilizing a low head, high specific speed booster pump in the hot leg of the coolant loop with the main pump located in the cold leg of the loop, thereby providing the advantages of operating the main pump in the hot leg with the reliability of cold leg pump operation.

  11. Liquid metal pump

    DOEpatents

    Pennell, William E.

    1982-01-01

    The liquid metal pump comprises floating seal rings and attachment of the pump diffuser to the pump bowl for isolating structural deflections from the pump shaft bearings. The seal rings also eliminate precision machining on large assemblies by eliminating the need for a close tolerance fit between the mounting surfaces of the pump and the seals. The liquid metal pump also comprises a shaft support structure that is isolated from the pump housing for better preservation of alignment of shaft bearings. The shaft support structure also allows for complete removal of pump internals for inspection and repair.

  12. Winding for linear pump

    DOEpatents

    Kliman, G.B.; Brynsvold, G.V.; Jahns, T.M.

    1989-08-22

    A winding and method of winding for a submersible linear pump for pumping liquid sodium are disclosed. The pump includes a stator having a central cylindrical duct preferably vertically aligned. The central vertical duct is surrounded by a system of coils in slots. These slots are interleaved with magnetic flux conducting elements, these magnetic flux conducting elements forming a continuous magnetic field conduction path along the stator. The central duct has placed therein a cylindrical magnetic conducting core, this core having a cylindrical diameter less than the diameter of the cylindrical duct. The core once placed to the duct defines a cylindrical interstitial pumping volume of the pump. This cylindrical interstitial pumping volume preferably defines an inlet at the bottom of the pump, and an outlet at the top of the pump. Pump operation occurs by static windings in the outer stator sequentially conveying toroidal fields from the pump inlet at the bottom of the pump to the pump outlet at the top of the pump. The winding apparatus and method of winding disclosed uses multiple slots per pole per phase with parallel winding legs on each phase equal to or less than the number of slots per pole per phase. The slot sequence per pole per phase is chosen to equalize the variations in flux density of the pump sodium as it passes into the pump at the pump inlet with little or no flux and acquires magnetic flux in passage through the pump to the pump outlet. 4 figs.

  13. Winding for linear pump

    DOEpatents

    Kliman, Gerald B.; Brynsvold, Glen V.; Jahns, Thomas M.

    1989-01-01

    A winding and method of winding for a submersible linear pump for pumping liquid sodium is disclosed. The pump includes a stator having a central cylindrical duct preferably vertically aligned. The central vertical duct is surrounded by a system of coils in slots. These slots are interleaved with magnetic flux conducting elements, these magnetic flux conducting elements forming a continuous magnetic field conduction path along the stator. The central duct has placed therein a cylindrical magnetic conducting core, this core having a cylindrical diameter less than the diameter of the cylindrical duct. The core once placed to the duct defines a cylindrical interstitial pumping volume of the pump. This cylindrical interstitial pumping volume preferably defines an inlet at the bottom of the pump, and an outlet at the top of the pump. Pump operation occurs by static windings in the outer stator sequentially conveying toroidal fields from the pump inlet at the bottom of the pump to the pump outlet at the top of the pump. The winding apparatus and method of winding disclosed uses multiple slots per pole per phase with parallel winding legs on each phase equal to or less than the number of slots per pole per phase. The slot sequence per pole per phase is chosen to equalize the variations in flux density of the pump sodium as it passes into the pump at the pump inlet with little or no flux and acquires magnetic flux in passage through the pump to the pump outlet.

  14. Vacuum tool manipulator

    SciTech Connect

    Zollinger, W.T.

    1992-12-31

    This invention is comprised of an apparatus for manipulating a vacuum hose in a reactor vessel comprising a housing with two opposing openings, an arm carried by the housing and deployable from a stowed position essentially completely within the housing to an extended position where the arm extends through the two openings in a generally horizontal position. The arm preferably has a two-fingered gripping device for gripping the vacuum hose but may carry a different end effector such as a grinding wheel. The fingers are opened and closed by one air cylinder. A second air cylinder extends the device. A third air cylinder within the housing pivotally pulls the opposing end of the arm into the housing via a pivoting member pivotally connected between the third air cylinder shaft and the arm.

  15. Vacuum tool manipulator

    DOEpatents

    Zollinger, W.T.

    1993-11-23

    Apparatus for manipulating a vacuum hose in a reactor vessel comprises a housing with two opposing openings, an arm carried by the housing and deployable from a stowed position essentially completely within the housing to an extended position where the arm extends through the two openings in a generally horizontal position. The arm preferably has a two-fingered gripping device for gripping the vacuum hose but may carry a different end effector such as a grinding wheel. The fingers are opened and closed by one air cylinder. A second air cylinder extends the device. A third air cylinder within the housing pivotally pulls the opposing end of the arm into the housing via a pivoting member pivotally connected between the third air cylinder shaft and the arm. 6 figures.

  16. Compact vacuum insulation

    DOEpatents

    Benson, David K.; Potter, Thomas F.

    1993-01-01

    An ultra-thin compact vacuum insulation panel is comprised of two hard, but bendable metal wall sheets closely spaced apart from each other and welded around the edges to enclose a vacuum chamber. Glass or ceramic spacers hold the wall sheets apart. The spacers can be discrete spherical beads or monolithic sheets of glass or ceramic webs with nodules protruding therefrom to form essentially "point" or "line" contacts with the metal wall sheets. In the case of monolithic spacers that form "line" contacts, two such spacers with the line contacts running perpendicular to each other form effectively "point" contacts at the intersections. Corrugations accommodate bending and expansion, tubular insulated pipes and conduits, and preferred applications are also included.

  17. Compact vacuum insulation embodiments

    DOEpatents

    Benson, David K.; Potter, Thomas F.

    1992-01-01

    An ultra-thin compact vacuum insulation panel is comprised of two hard, but bendable metal wall sheets closely spaced apart from each other and welded around the edges to enclose a vacuum chamber. Glass or ceramic spacers hold the wall sheets apart. The spacers can be discrete spherical beads or monolithic sheets of glass or ceramic webs with nodules protruding therefrom to form essentially "point" or "line" contacts with the metal wall sheets. In the case of monolithic spacers that form "line" contacts, two such spacers with the line contacts running perpendicular to each other form effectively "point" contacts at the intersections. Corrugations accommodate bending and expansion, tubular insulated pipes and conduits, and preferred applications are also included.

  18. Compact vacuum insulation embodiments

    DOEpatents

    Benson, D.K.; Potter, T.F.

    1992-04-28

    An ultra-thin compact vacuum insulation panel is comprised of two hard, but bendable metal wall sheets closely spaced apart from each other and welded around the edges to enclose a vacuum chamber. Glass or ceramic spacers hold the wall sheets apart. The spacers can be discrete spherical beads or monolithic sheets of glass or ceramic webs with nodules protruding therefrom to form essentially point' or line' contacts with the metal wall sheets. In the case of monolithic spacers that form line' contacts, two such spacers with the line contacts running perpendicular to each other form effectively point' contacts at the intersections. Corrugations accommodate bending and expansion, tubular insulated pipes and conduits, and preferred applications are also included. 26 figs.

  19. Compact vacuum insulation

    DOEpatents

    Benson, D.K.; Potter, T.F.

    1993-01-05

    An ultra-thin compact vacuum insulation panel is comprised of two hard, but bendable metal wall sheets closely spaced apart from each other and welded around the edges to enclose a vacuum chamber. Glass or ceramic spacers hold the wall sheets apart. The spacers can be discrete spherical beads or monolithic sheets of glass or ceramic webs with nodules protruding therefrom to form essentially point'' or line'' contacts with the metal wall sheets. In the case of monolithic spacers that form line'' contacts, two such spacers with the line contacts running perpendicular to each other form effectively point'' contacts at the intersections. Corrugations accommodate bending and expansion, tubular insulated pipes and conduits, and preferred applications are also included.

  20. Vacuum tool manipulator

    DOEpatents

    Zollinger, William T.

    1993-01-01

    Apparatus for manipulating a vacuum hose in a reactor vessel comprises a housing with two opposing openings, an arm carried by the housing and deployable from a stowed position essentially completely within the housing to an extended position where the arm extends through the two openings in a generally horizontal position. The arm preferably has a two-fingered gripping device for gripping the vacuum hose but may carry a different end effector such as a grinding wheel. The fingers are opened and closed by one air cylinder. A second air cylinder extends the device. A third air cylinder within the housing pivotally pulls the opposing end of the arm into the housing via a pivoting member pivotally connected between the third air cylinder shaft and the arm.

  1. Integrated structure vacuum tube

    NASA Technical Reports Server (NTRS)

    Dimeff, J.; Kerwin, W. J. (Inventor)

    1976-01-01

    High efficiency, multi-dimensional thin film vacuum tubes suitable for use in high temperature, high radiation environments are described. The tubes are fabricated by placing thin film electrode members in selected arrays on facing interior wall surfaces of an alumina substrate envelope. Cathode members are formed using thin films of triple carbonate. The photoresist used in photolithography aids in activation of the cathodes by carbonizing and reacting with the reduced carbonates when heated in vacuum during forming. The finely powdered triple carbonate is mixed with the photoresist used to delineate the cathode locations in the conventional solid state photolithographic manner. Anode and grid members are formed using thin films of refractory metal. Electron flow in the tubes is between grid elements from cathode to anode as in a conventional three-dimensional tube.

  2. Thermal Vacuum Control Systems Options for Test Facilities

    NASA Technical Reports Server (NTRS)

    Marchetti, John

    2008-01-01

    This presentation suggests several Thermal Vacuum System (TVAC) control design approach methods for TVAC facilities. Over the past several years many aerospace companies have or are currently upgrading their TVAC testing facilities whether it be by upgrading old equipment or purchasing new. In doing so they are updating vacuum pumping and thermal capabilities of their chambers as well as their control systems. Although control systems are sometimes are considered second to the vacuum or thermal system upgrade process, they should not be taken lightly and must be planned and implemented with the equipment it is to control. Also, emphasis should be placed on how the operators will use the system as well as the requirements of "their" customers. Presented will be various successful methods of TVAC control systems from Programmable Logic Controller (PLC) based to personal computer (PC) based control.

  3. Hydraulic pump

    SciTech Connect

    Polak, P.R.; Jantzen, D.E.

    1984-05-15

    This invention relates to an improved pump jack characterized by a hollow piston rod which telescopes down over the sucker rod to which it is clamped for reciprocating motion. The cylinder, in turn, is fastened in fixed position directly to the upper exposed end of the well casing. As fluid is introduced into the lower end of the cylinder it raises the piston into engagement with a pushrod housed in the upper cylinder head that lifts switch-actuating means associated therewith into a position operative to actuate a switch located adjacent thereto thereby causing the latter to change state and actuate a multi-function solenoid valve so as to cut off fluid flow to the cylinder. As gravity lowers the sucker rod and piston exhausting the hydraulic fluid therebeneath, an adjustable stop engages the pushrod from above so as to return it together with the switch-actuating means associated therewith to their original positions thereby resetting the switch to complete the operating cycle.

  4. Whole blood pumping with a microthrottle pump

    PubMed Central

    Davies, M. J.; Johnston, I. D.; Tan, C. K. L.; Tracey, M. C.

    2010-01-01

    We have previously reported that microthrottle pumps (MTPs) display the capacity to pump solid phase suspensions such as polystyrene beads which prove challenging to most microfluidic pumps. In this paper we report employing a linear microthrottle pump (LMTP) to pump whole, undiluted, anticoagulated, human venous blood at 200 μl min−1 with minimal erythrocyte lysis and no observed pump blockage. LMTPs are particularly well suited to particle suspension transport by virtue of their relatively unimpeded internal flow-path. Micropumping of whole blood represents a rigorous real-world test of cell suspension transport given blood’s high cell content by volume and erythrocytes’ relative fragility. A modification of the standard Drabkin method and its validation to spectrophotometrically quantify low levels of erythrocyte lysis by hemoglobin release is also reported. Erythrocyte lysis rates resulting from transport via LMTP are determined to be below one cell in 500 at a pumping rate of 102 μl min−1. PMID:21264059

  5. Vacuum Characterization and Improvement for the Jefferson Lab Polarized Electron Source

    SciTech Connect

    Stutzman, Marcy L.; Poelker, Matthew; Adderley, Philip A.; Mamun, Md Abdullah

    2015-09-01

    Operating the JLab polarized electron source with high reliability and long lifetime requires vacuum near the XHV level, defined as pressure below 7.5×10-13 Torr. This paper describes ongoing vacuum research at Jefferson Lab including characterization of outgassing rates for surface coatings and heat treatments, ultimate pressure measurements, investigation of pumping including an XHV cryopump, and characterization of ionization gauges in this pressure regime.

  6. Multiple pump housing

    DOEpatents

    Donoho, II, Michael R.; Elliott, Christopher M.

    2010-03-23

    A fluid delivery system includes a first pump having a first drive assembly, a second pump having a second drive assembly, and a pump housing. At least a portion of each of the first and second pumps are located in the housing.

  7. Types of Breast Pumps

    MedlinePlus

    ... Powered and Electric Pumps A powered breast pump uses batteries or a cord plugged into an electrical outlet ... pumps rely on a power source, women who use powered breast pumps should be prepared for emergency situations when electricity or extra batteries may not be available. If breastfeeding is not ...

  8. Architecture and operation of the Z Pulsed Power Facility vacuum system.

    SciTech Connect

    Riddle, Allen Chauncey; Petmecky, Don; Weed, John Woodruff

    2010-11-01

    The Z Pulsed Power Facility at Sandia National Laboratories in Albuquerque, New Mexico, USA is one of the world's premier high energy density physics facilities. The Z Facility derives its name from the z-pinch phenomena which is a type of plasma confinement system that uses the electrical current in the plasma to generate a magnetic field that compresses it. Z refers to the direction of current flow, the z axis in a three dimensional Cartesian coordinate system. The multiterawatt, multimegajoule electrical pulse the Facility produces is 100-400 nanoseconds in time. Research and development programs currently being conducted on the Z Facility include inertial confinement fusion, dynamic material properties, laboratory astrophysics and radiation effects. The Z Facility vacuum system consists of two subsystems, center section and load diagnostics. Dry roughing pumps and cryogenic high vacuum pumps are used to evacuate the 40,000 liter, 200 square meter center section of the facility where the experimental load is located. Pumping times on the order of two hours are required to reduce the pressure from atmospheric to 10{sup -5} Torr. The center section is cycled from atmosphere to high vacuum for each experiment. The facility is capable of conducting one to two experiments per day. Numerous smaller vacuum pumping systems are used to evacuate load diagnostics. The megajoules of energy released during an experiment causes damage to the Facility that presents numerous challenges for reliable operation of the vacuum system.

  9. Rolling through a vacuum

    NASA Astrophysics Data System (ADS)

    van der Schaar, Jan Pieter; Yang, I.-Sheng

    2013-12-01

    We clarify under what conditions slow-roll inflation can continue almost undisturbed, while briefly evolving through a (semi-classically) metastable false vacuum. Furthermore, we look at potential signatures in the primordial power spectrum that could point towards the existence of traversed metastable false vacua. Interestingly, the theoretical constraints for the existence of traversable metastable vacua imply that Planck should be able to detect the resulting features in the primordial power spectrum. In other words, if Planck does not see features this immediately implies the non-existence of metastable false vacua rolled through during the inflationary epoch.

  10. Avoiding Death by Vacuum

    NASA Astrophysics Data System (ADS)

    Barroso, A.; Ferreira, P. M.; Ivanov, I.; Santos, R.; Silva, João P.

    2013-07-01

    The two-Higgs doublet model (2HDM) can have two electroweak breaking, CP-conserving, minima. The possibility arises that the minimum which corresponds to the known elementary particle spectrum is metastable, a possibility we call the "panic vacuum". We present analytical bounds on the parameters of the softly broken Peccei-Quinn 2HDM which are necessary and sufficient conditions to avoid this possibility. We also show that, for this particular model, the current LHC data already tell us that we are necessarily in the global minimum of the theory, regardless of any cosmological considerations about the lifetime of the false vacua.

  11. Vacuum Beat Wave Accelerator

    NASA Astrophysics Data System (ADS)

    Moore, C. I.; Hafizi, B.; Ting, A.; Burris, H. R.; Sprangle, P.; Esarey, E.; Ganguly, A.; Hirshfield, J. L.

    1997-11-01

    The Vacuum Beat Wave Accelerator (VBWA) is a particle acceleration scheme which uses the non-linear ponderomotive beating of two different frequency laser beams to accelerate electrons. A proof-of-principle experiment to demonstrate the VBWA is underway at the Naval Research Laboratory (NRL). This experiment will use the beating of a 1054 nm and 527 nm laser pulse from the NRL T-cubed laser to generate the beat wave and a 4.5 MeV RF electron gun as the electron source. Simulation results and the experimental design will be presented. The suitability of using axicon or higher order Gaussian laser beams will also be discussed.

  12. Thermal Vacuum Test Facility.

    DTIC Science & Technology

    1984-01-31

    tne power has a rear terminal sensor input for this Probe, use it. Otherwiseq connect the probe to the front panel. The end of the sensor should be...outlet on the front panel of the vacuum chamber. BUS CONNECTtONS: Plug the 1/0 expander card into one of the three calculator slots. Cover the other two...mating cable. Soth connectors on the slave disk are identical, so either one can be used. This cable also locks into place at each end . Connect the other

  13. PIV Measurements in Pumps

    DTIC Science & Technology

    2006-11-01

    Pump Impeller Fig. 37 shows the top view of pump test rig for radial impeller pumps . The goal of this experiment is cavitation observation and their...PIV Measurements in Pumps 5 - 28 RTO-EN-AVT-143 Figure 37: Test Rig for Combined PIV Measurements and Cavitation Observation. Figure 38...RTO-EN-AVT-143 5 - 1 PIV Measurements in Pumps Dr. Detlev L. Wulff TU Braunschweig Institut für Strömungsmaschinen Langer Kamp 6 D-38106

  14. [Effect of the vacuum stimuli on length nipple-areola complex of the woman lactation mammary gland].

    PubMed

    Il'in, V I; Alekseev, N P

    2014-02-01

    The aim of this study was to determine the effect of vacuum stimuli on time increasing and decreasing of the length areola-nipple complex lactating women. At the maximum comfortable vacuum (140-160 mm Hg) length areola increases for 90-100 ms to maximum length. After vacuum stimuli were off a length of areola was decreased and reach the rest level for 120-150 ms. The length of the nipple was unchanged. This data it is necessary to optimize work breast pump with tactile component. The temporal characteristics of the length of areola under the influence of physiologically acceptable vacuum indicate that in breast pump with tactile component compression stimuli should act on the areola not less that 100 ms after the beginning of vacuum stimuli.

  15. Motor actuated vacuum door

    NASA Astrophysics Data System (ADS)

    Hanagud, A. V.

    1986-10-01

    Doors that allow scientific instruments to record and retrieve the observed data are often required to be designed and installed as a part of sounding rocket hardware. The motor-actuated vacuum door was designed to maintain a medium vacuum of the order of 0.0001 torr or better while closed, and to provide an opening 15 inches long x 8.5 inches wide while open for cameras to image Halley's comet. When the electric motor receives the instruction to open the door through the payload battery, timer, and relay circuit, the first operation is to unlock the door. After unlatching, the torque transmitted by the motor to the main shaft through the links opens the door. A microswitch actuator, which rides on the linear motion conversion mechanism, is adjusted to trip the limit switch at the end of the travel. The process is repeated in the reverse order to close the door. 'O' rings are designed to maintain the seal. Door mechanisms similar to the one described have flown on Aerobee 17.018 and Black Brant 27.047 payloads.

  16. Portable vacuum object handling device

    DOEpatents

    Anderson, G.H.

    1983-08-09

    The disclosure relates to a portable device adapted to handle objects which are not to be touched by hand. A piston and bore wall form a vacuum chamber communicating with an adaptor sealably engageable with an object to be lifted. The piston is manually moved and set to establish vacuum. A valve is manually actuatable to apply the vacuum to lift the object. 1 fig.

  17. Simulations of light-light scattering in quantum vacuum

    NASA Astrophysics Data System (ADS)

    Carneiro, Pedro; Grismayer, Thomas; Silva, LuíS.; Fonseca, Ricardo

    2016-10-01

    Facilities such as the Extreme Light Infrastructure (ELI) or the VULCAN 20 PW project, as well as the Petta-Watt SLAC project, coupled with the x-ray LCLSII source will allow to perform the first experiments on the probing of quantum vacuum. In our work, we developed a numerical method to self-consistently solve the nonlinear system of Maxwell's equations including quantum corrections of vacuum polarization. The robustness of our algorithm allied to the ability to integrate this tool within a particle-in-cell (PIC) method, represents an important milestone in modeling future planned experiments to prove the existence of the quantum vacuum. Such experiments aim to measure the induced ellipticity on a x-ray pulse after probing a strong optical pump due to the quantum vacuum fluctuations. We present simulation results of both the ellipticity induced and polarization rotation, using realistic laser parameters of the Petta-Watt SLAC project, and the x-ray LCLSII source, whilst taking into account all finite-size multi-dimensional effects. We show how the ellipticity induced varies as a function of the distance to the axis of the beam, proving the importance of taking into account finite-size effects. This work serves as an important tool to complement existing efforts within the community to probe the effects of the quantum vacuum, in the strong field regime, for the first time.

  18. Note: Hollow cathode lamp with integral, high optical efficiency isolation valve: A modular vacuum ultraviolet source

    NASA Astrophysics Data System (ADS)

    Sloan Roberts, F.; Anderson, Scott L.

    2013-12-01

    The design and operating conditions of a hollow cathode discharge lamp for the generation of vacuum ultraviolet radiation, suitable for ultrahigh vacuum (UHV) application, are described in detail. The design is easily constructed, and modular, allowing it to be adapted to different experimental requirements. A thin isolation valve is built into one of the differential pumping stages, isolating the discharge section from the UHV section, both for vacuum safety and to allow lamp maintenance without venting the UHV chamber. The lamp has been used both for ultraviolet photoelectron spectroscopy of surfaces and as a "soft" photoionization source for gas-phase mass spectrometry.

  19. Vacuum leak detector and method

    DOEpatents

    Edwards, Jr., David

    1983-01-01

    Apparatus and method for detecting leakage in a vacuum system involves a moisture trap chamber connected to the vacuum system and to a pressure gauge. Moisture in the trap chamber is captured by freezing or by a moisture adsorbent to reduce the residual water vapor pressure therein to a negligible amount. The pressure gauge is then read to determine whether the vacuum system is leaky. By directing a stream of carbon dioxide or helium at potentially leaky parts of the vacuum system, the apparatus can be used with supplemental means to locate leaks.

  20. Initial conditioning of the TFTR vacuum vessel

    SciTech Connect

    Dylla, H.F.; Blanchard, W.R.; Krawchuk, R.B.; Hawryluk, R.J.; Owens, D.K.

    1984-01-01

    We report on the initial conditioning of the Tokamak Fusion Test Reactor (TFTR) vacuum vessel prior to the initiation of first plasma discharges, and during subsequent operation with high power ohmically-heated plasmas. Following evacuation of the 86 m/sup 3/ vessel with the 10/sup 4/ 1/s high vacuum pumping system, the vessel was conditioned by a 15 A dc glow discharge in H/sub 2/ at a pressure of 5 mTorr. Rapid-pulse discharge cleaning was used subsequently to preferentially condition the graphite plasma limiters. The effectiveness of the discharge cleaning was monitored by measuring the exhaust rates of the primary discharge products (CO/C/sub 2/H/sub 4/, CH/sub 4/, and H/sub 2/O). After 175 hours of glow discharge treatment, the equivalent of 50 monolayers of C and O was removed from the vessel, and the partial pressures of impurity gases were reduced to the range of 10/sup -9/-10/sup -10/ Torr.

  1. Design and Construction of the NSTX Bakeout, Cooling and Vacuum Systems

    SciTech Connect

    L.E. Dudek; M. Kalish; R. Gernhardt; R.F. Parsells; W. Blanchard

    1999-11-01

    This paper will describe the design, construction and initial operation of the NSTX bakeout, water cooling and vacuum systems. The bakeout system is designed for two modes of operation. The first mode allows heating of the first wall components to 350 degrees C while the external vessel is cooled to 150 degrees C. The second mode cools the first wall to 150 degrees C and the external vessel to 50 degrees C. The system uses a low viscosity heat transfer oil which is capable of high temperature low pressure operation. The NSTX Torus Vacuum Pumping System (TVPS) is designed to achieve a base pressure of approximately 1x10 (superscript -8) Torr and to evacuate the plasma fuel gas loads in less than 5 minutes between discharges. The vacuum pumping system is capable of a pumping speed of approximately 3400 l/s for deuterium. The hardware consists of two turbo molecular pumps (TMPs) and a mechanical pump set consisting of a mechanical and a Roots blower pump. A PLC is used as the control system to provide remote monitoring, control and software interlock capability. The NSTX cooling water provides chilled, de ionized water for heat removal in the TF, OH and PF, power supplies, bus bar systems, and various diagnostics. The system provides flow monitoring via a PLC to prevent damage due to loss of flow.

  2. Continuously pumping and reactivating gas pump

    DOEpatents

    Batzer, T.H.; Call, W.R.

    Apparatus for continuous pumping using cycling cryopumping panels. A plurality of liquid helium cooled panels are surrounded by movable nitrogen cooled panels that alternatively expose or shield the helium cooled panels from the space being pumped. Gases condense on exposed helium cooled panels until the nitrogen cooled panels are positioned to isolate the helium cooled panels. The helium cooled panels are incrementally warmed, causing captured gases to accumulate at the base of the panels, where an independant pump removes the gases. After the helium cooled panels are substantially cleaned of condensate, the nitrogen cooled panels are positioned to expose the helium cooled panels to the space being pumped.

  3. Continuously pumping and reactivating gas pump

    DOEpatents

    Batzer, Thomas H.; Call, Wayne R.

    1984-01-01

    Apparatus for continuous pumping using cycling cyropumping panels. A plurality of liquid helium cooled panels are surrounded by movable nitrogen cooled panels the alternatively expose or shield the helium cooled panels from the space being pumped. Gases condense on exposed helium cooled panels until the nitrogen cooled panels are positioned to isolate the helium cooled panels. The helium cooled panels are incrementally warmed, causing captured gases to accumulate at the base of the panels, where an independent pump removes the gases. After the helium cooled panels are substantially cleaned of condensate, the nitrogen cooled panels are positioned to expose the helium cooled panels to the space being pumped.

  4. Operation of Fusion Reactors in One Atmosphere of Air Instead of Vacuum Systems

    NASA Astrophysics Data System (ADS)

    Roth, J. Reece

    2009-07-01

    Engineering design studies of both magnetic and inertial fusion power plants have assumed that the plasma will undergo fusion reactions in a vacuum environment. Operation under vacuum requires an expensive additional major system for the reactor-a vacuum vessel with vacuum pumping, and raises the possibility of sudden unplanned outages if the vacuum containment is breached. It would be desirable in many respects if fusion reactors could be made to operate at one atmosphere with air surrounding the plasma, thus eliminating the requirement of a pressure vessel and vacuum pumping. This would have obvious economic, reliability, and engineering advantages for currently envisaged power plant reactors; it would make possible forms of reactor control not possible under vacuum conditions (i.e. adiabatic compression of the fusion plasma by increasing the pressure of surrounding gas); it would allow reactors used as aircraft engines to operate as turbojets or ramjets in the atmosphere, and it would allow reactors used as fusion rockets to take off from the surface of the earth instead of low earth orbit.

  5. Vacuum pressure generation via microfabricated converging-diverging nozzles for operation of automated pneumatic logic.

    PubMed

    Christoforidis, Theodore; Werner, Erik M; Hui, Elliot E; Eddington, David T

    2016-08-01

    Microfluidic devices with integrated pneumatic logic enable automated fluid handling without requiring external control instruments. These chips offer the additional advantage that they may be powered by vacuum and do not require an electricity source. This work describes a microfluidic converging-diverging (CD) nozzle optimized to generate vacuum at low input pressures, making it suitable for microfluidic applications including powering integrated pneumatic logic. It was found that efficient vacuum pressure was generated for high aspect ratios of the CD nozzle constriction (or throat) width to height and diverging angle of 3.6(o). In specific, for an inlet pressure of 42.2 psia (290.8 kPa) and a volumetric flow rate of approximately 1700 sccm, a vacuum pressure of 8.03 psia (55.3 kPa) was generated. To demonstrate the capabilities of our converging - diverging nozzle device, we connected it to a vacuum powered peristaltic pump driven by integrated pneumatic logic and obtained tunable flow rates from 0 to 130 μL/min. Finally, we demonstrate a proof of concept system for use where electricity and vacuum pressure are not readily available by powering a CD nozzle with a bicycle tire pump and pressure regulator. This system is able to produce a stable vacuum sufficient to drive pneumatic logic, and could be applied to power automated microfluidics in limited resource settings.

  6. Optimal quantum pumps.

    PubMed

    Avron, J E; Elgart, A; Graf, G M; Sadun, L

    2001-12-03

    We study adiabatic quantum pumps on time scales that are short relative to the cycle of the pump. In this regime the pump is characterized by the matrix of energy shift which we introduce as the dual to Wigner's time delay. The energy shift determines the charge transport, the dissipation, the noise, and the entropy production. We prove a general lower bound on dissipation in a quantum channel and define optimal pumps as those that saturate the bound. We give a geometric characterization of optimal pumps and show that they are noiseless and transport integral charge in a cycle. Finally we discuss an example of an optimal pump related to the Hall effect.

  7. LIGO vacuum system study

    NASA Technical Reports Server (NTRS)

    Livas, Jeffrey C.; Moore, Boude C.

    1988-01-01

    A laser interferometer gravitational wave observatory (LIGO) is being developed with sensitivities which will have a high probability of detecting gravitational waves from astrophysical sources. A major component of LIGO is a total of 16 km of 1.2 m (48 inch) diameter tube at a pressure of less than 10 to the minus 8th power torr. It will be of 304L stainless steel procured directly from the steel mills with the initial hydrogen content specially reduced. Projections of the outgassing rates of hydrogen and of water vapor as a function of time are given and the uncertainties discussed. Based on these, a preliminary analysis of the vacuum system is presented.

  8. ULTRA HIGH VACUUM VALVE

    DOEpatents

    Fry, W.A.

    1962-05-29

    A valve for high vacuum applications such as the CStellarator where chamber pressures as low as 2 x 10/sup -10/ mm Hg are necessary is designed with a line-of-sight path through the valve for visual inspection of the contents of reactants in such chambers. The valve comprises a turnable resilient metal ball having an aperture therethrough, means for selectively turning the ball to rotate the axis of its line-of-sight path, and soft, deformable opposing orifices that are movable relatively toward said ball to seal with opposite ball surfaces upon said movement of said axis of said line-of-sight path. The valve also includes a bellows seal connected between said orifices and internal actuating means that eliminates the requirement for gasketed turnable valve closing stems. (AEC)

  9. Viability of Cladosporium herbarum spores under 157 nm laser and vacuum ultraviolet irradiation, low temperature (10 K) and vacuum

    NASA Astrophysics Data System (ADS)

    Sarantopoulou, E.; Stefi, A.; Kollia, Z.; Palles, D.; Petrou, P. S.; Bourkoula, A.; Koukouvinos, G.; Velentzas, A. D.; Kakabakos, S.; Cefalas, A. C.

    2014-09-01

    Ultraviolet photons can damage microorganisms, which rarely survive prolonged irradiation. In addition to the need for intact DNA, cell viability is directly linked to the functionality of the cell wall and membrane. In this work, Cladosporium herbarum spore monolayers exhibit high viability (7%) when exposed to 157 nm laser irradiation (412 kJm-2) or vacuum-ultraviolet irradiation (110-180 nm) under standard pressure and temperature in a nitrogen atmosphere. Spore viability can be determined by atomic-force microscopy, nano-indentation, mass, μ-Raman and attenuated reflectance Fourier-transform far-infrared spectroscopies and DNA electrophoresis. Vacuum ultraviolet photons cause molecular damage to the cell wall, but radiation resistance in spores arises from the activation of a photon-triggered signaling reaction, expressed via the exudation of intracellular substances, which, in combination with the low penetration depth of vacuum-ultraviolet photons, shields DNA from radiation. Resistance to phototoxicity under standard conditions was assessed, as was resistance to additional environmental stresses, including exposure in a vacuum, under different rates of change of pressure during pumping time and low (10 K) temperatures. Vacuum conditions were far more destructive to spores than vacuum-ultraviolet irradiation, and UV-B photons were two orders of magnitude more damaging than vacuum-ultraviolet photons. The viability of irradiated spores was also enhanced at 10 K. This work, in addition to contributing to the photonic control of the viability of microorganisms exposed under extreme conditions, including decontamination of biological warfare agents, outlines the basis for identifying bio-signaling in vivo using physical methodologies.

  10. Viability of Cladosporium herbarum spores under 157 nm laser and vacuum ultraviolet irradiation, low temperature (10 K) and vacuum

    SciTech Connect

    Sarantopoulou, E. Stefi, A.; Kollia, Z.; Palles, D.; Cefalas, A. C.; Petrou, P. S.; Bourkoula, A.; Koukouvinos, G.; Kakabakos, S.; Velentzas, A. D.

    2014-09-14

    Ultraviolet photons can damage microorganisms, which rarely survive prolonged irradiation. In addition to the need for intact DNA, cell viability is directly linked to the functionality of the cell wall and membrane. In this work, Cladosporium herbarum spore monolayers exhibit high viability (7%) when exposed to 157 nm laser irradiation (412 kJm⁻²) or vacuum-ultraviolet irradiation (110–180 nm) under standard pressure and temperature in a nitrogen atmosphere. Spore viability can be determined by atomic-force microscopy, nano-indentation, mass, μ-Raman and attenuated reflectance Fourier-transform far-infrared spectroscopies and DNA electrophoresis. Vacuum ultraviolet photons cause molecular damage to the cell wall, but radiation resistance in spores arises from the activation of a photon-triggered signaling reaction, expressed via the exudation of intracellular substances, which, in combination with the low penetration depth of vacuum-ultraviolet photons, shields DNA from radiation. Resistance to phototoxicity under standard conditions was assessed, as was resistance to additional environmental stresses, including exposure in a vacuum, under different rates of change of pressure during pumping time and low (10 K) temperatures. Vacuum conditions were far more destructive to spores than vacuum-ultraviolet irradiation, and UV-B photons were two orders of magnitude more damaging than vacuum-ultraviolet photons. The viability of irradiated spores was also enhanced at 10 K. This work, in addition to contributing to the photonic control of the viability of microorganisms exposed under extreme conditions, including decontamination of biological warfare agents, outlines the basis for identifying bio-signaling in vivo using physical methodologies.

  11. Vacuum Energy Sequestering and Graviton Loops.

    PubMed

    Kaloper, Nemanja; Padilla, Antonio

    2017-02-10

    We recently formulated a local mechanism of vacuum energy sequester. This mechanism automatically removes all matter loop contributions to vacuum energy from the stress energy tensor which sources the curvature. Here we adapt the local vacuum energy sequestering mechanism to also cancel all the vacuum energy loops involving virtual gravitons, in addition to the vacuum energy generated by matter fields alone.

  12. Vacuum Energy Sequestering and Graviton Loops

    NASA Astrophysics Data System (ADS)

    Kaloper, Nemanja; Padilla, Antonio

    2017-02-01

    We recently formulated a local mechanism of vacuum energy sequester. This mechanism automatically removes all matter loop contributions to vacuum energy from the stress energy tensor which sources the curvature. Here we adapt the local vacuum energy sequestering mechanism to also cancel all the vacuum energy loops involving virtual gravitons, in addition to the vacuum energy generated by matter fields alone.

  13. Fluid sampling pump

    SciTech Connect

    Allen, P.V.; Nimberger, M.; Ward, R.L.

    1991-12-24

    This patent describes a fluid sampling pump for withdrawing pressurized sample fluid from a flow line and for pumping a preselected quantity of sample fluid with each pump driving stroke from the pump to a sample vessel, the sampling pump including a pump body defining a pump bore therein having a central axis, a piston slideably moveable within the pump bore and having a fluid inlet end and an opposing operator end, a fluid sample inlet port open to sample fluid in the flow line, a fluid sample outlet port for transmitting fluid from the pump bore to the sample vessel, and a line pressure port in fluid pressure sample fluid in the flow line, an inlet valve for selectively controlling sample fluid flow from the flow line through the fluid sample inlet port, an operator unit for periodically reciprocating the piston within the pump bore, and a controller for regulating the stroke of the piston within the pump bore, and thereby the quantity of fluid pumped with each pump driving stroke. It comprises a balanced check valve seat; a balanced check valve seal; a compression member; and a central plunger.

  14. Breather cloth for vacuum curing

    NASA Technical Reports Server (NTRS)

    Reed, M. W.

    1979-01-01

    Finely-woven nylon cloth that has been treated with Teflon improves vacuum adhesive bonding of coatings to substrates. Cloth is placed over coating; entire assembly, including substrate, coating, and cloth, is placed in plastic vacuum bag for curing. Cloth allows coating to "breathe" when bag is evacuated. Applications include bonding film coatings to solar concentrators and collectors.

  15. Multipurpose Vacuum Induction Processing System

    NASA Astrophysics Data System (ADS)

    Govindaraju, M.; Kulkarni, Deepak; Balasubramanian, K.

    2012-11-01

    Multipurpose vacuum processing systems are cost effective; occupy less space, multiple functional under one roof and user friendly. A multipurpose vacuum induction system was designed, fabricated and installed in a record time of 6 months time at NFTDC Hyderabad. It was designed to function as a) vacuum induction melting/refining of oxygen free electronic copper/pure metals, b) vacuum induction melting furnace for ferrous materials c) vacuum induction melting for non ferrous materials d) large vacuum heat treatment chamber by resistance heating (by detachable coil and hot zone) e) bottom discharge vacuum induction melting system for non ferrous materials f) Induction heat treatment system and g) directional solidification /investment casting. It contains provision for future capacity addition. The attachments require to manufacture multiple shaped castings and continuous rod casting can be added whenever need arises. Present capacity is decided on the requirement for 10years of development path; presently it has 1.2 ton liquid copper handling capacity. It is equipped with provision for capacity addition up to 2 ton liquid copper handling capacity in future. Provision is made to carry out the capacity addition in easy steps quickly. For easy operational maintenance and troubleshooting, design was made in easily detachable sections. High vacuum system is also is detachable, independent and easily movable which is first of its kind in the country. Detailed design parameters, advantages and development history are presented in this paper.

  16. Vacuum Enhanced Cutaneous Biopsy Instrument

    SciTech Connect

    Collins, Joseph

    1999-06-25

    A syringe-like disposable cutaneous biopsy instrument equipped with a tubular blade at its lower end, and designed so that a vacuum is created during use, said vacuum serving to retain undeformed a plug of tissue cut from a patient's skin.

  17. Purifying Aluminum by Vacuum Distillation

    NASA Technical Reports Server (NTRS)

    Du Fresne, E. R.

    1985-01-01

    Proposed method for purifying aluminum employs one-step vacuum distillation. Raw material for process impure aluminum produced in electrolysis of aluminum ore. Impure metal melted in vacuum. Since aluminum has much higher vapor pressure than other constituents, boils off and condenses on nearby cold surfaces in proportions much greater than those of other constituents.

  18. Vacuum flash evaporated polymer composites

    DOEpatents

    Affinito, J.D.; Gross, M.E.

    1997-10-28

    A method for fabrication of polymer composite layers in a vacuum is disclosed. More specifically, the method of dissolving salts in a monomer solution, vacuum flash evaporating the solution, condensing the flash evaporated solution as a liquid film, and forming the condensed liquid film into a polymer composite layer on a substrate is disclosed.

  19. Vacuum flash evaporated polymer composites

    DOEpatents

    Affinito, John D.; Gross, Mark E.

    1997-01-01

    A method for fabrication of polymer composite layers in a vacuum is disclosed. More specifically, the method of dissolving salts in a monomer solution, vacuum flash evaporating the solution, condensing the flash evaporated solution as a liquid film, and forming the condensed liquid film into a polymer composite layer on a substrate is disclosed.

  20. Vacuum Gas Tungsten Arc Welding

    NASA Technical Reports Server (NTRS)

    Weeks, J. L.; Todd, D. T.; Wooten, J. R.

    1997-01-01

    A two-year program investigated vacuum gas tungsten arc welding (VGTAW) as a method to modify or improve the weldability of normally difficult-to-weld materials. After a vacuum chamber and GTAW power supply were modified, several difficult-to-weld materials were studied and key parameters developed. Finally, Incoloy 903 weld overlays were produced without microfissures.

  1. Vacuum enhanced cutaneous biopsy instrument

    DOEpatents

    Collins, Joseph

    2000-01-01

    A syringe-like disposable cutaneous biopsy instrument equipped with a tubular blade at its lower end, and designed so that a vacuum is created during use, said vacuum serving to retain undeformed a plug of tissue cut from a patient's skin.

  2. Gas pump with movable gas pumping panels

    DOEpatents

    Osher, J.L.

    Apparatus for pumping gas continuously a plurality of articulated panels of getter material, each of which absorbs gases on one side while another of its sides is simultaneously reactivated in a zone isolated by the panels themselves from a working space being pumped.

  3. Bubbling the false vacuum away

    SciTech Connect

    Gleiser, M.; Rogers, B.; Thorarinson, J.

    2008-01-15

    We investigate the role of nonperturbative, bubblelike inhomogeneities on the decay rate of false-vacuum states in two- and three-dimensional scalar field theories. The inhomogeneities are induced by setting up large-amplitude oscillations of the field about the false vacuum, as, for example, after a rapid quench or in certain models of cosmological inflation. We show that, for a wide range of parameters, the presence of large-amplitude bubblelike inhomogeneities greatly accelerates the decay rate, changing it from the well-known exponential suppression of homogeneous nucleation to a power-law suppression. It is argued that this fast, power-law vacuum decay--known as resonant nucleation--is promoted by the presence of long-lived oscillons among the nonperturbative fluctuations about the false vacuum. A phase diagram is obtained distinguishing three possible mechanisms for vacuum decay: homogeneous nucleation, resonant nucleation, and crossover. Possible applications are briefly discussed.

  4. Hadron Contribution to Vacuum Polarisation

    NASA Astrophysics Data System (ADS)

    Davier, M.; Hoecker, A.; Malaescu, B.; Zhang, Z.

    2016-10-01

    Precision tests of the Standard Theory require theoretical predictions taking into account higher-order quantum corrections. Among these vacuum polarisation plays a predominant role. Vacuum polarisation originates from creation and annihilation of virtual particle-antiparticle states. Leptonic vacuum polarisation can be computed from quantum electrodynamics. Hadronic vacuum polarisation cannot because of the non-perturbative nature of QCD at low energy. The problem is remedied by establishing dispersion relations involving experimental data on the cross section for e+ e- annihilation into hadrons. This chapter sets the theoretical and experimental scene and reviews the progress achieved in the last decades thanks to more precise and complete data sets. Among the various applications of hadronic vacuum polarisation calculations, two are emphasised: the contribution to the anomalous magnetic moment of the muon, and the running of the fine structure constant α to the Z mass scale. They are fundamental ingredients to high precision tests of the Standard Theory.

  5. ISRU Soil Mechanics Vacuum Facility: Soil Bin Preparation and Simulant Strength Characterization

    NASA Technical Reports Server (NTRS)

    Kleinhenz, Julie; Wilkinson, Allen

    2012-01-01

    Testing in relevant environments is key to exploration mission hardware development. This is true on both the component level (in early development) and system level (in late development stages). During ISRU missions the hardware will interface with the soil (digging, roving, etc) in a vacuum environment. A relevant test environment will therefore involve a vacuum chamber with a controlled, conditioned simulant bed. However, in earth-based granular media, such as lunar soil simulant, gases trapped within the material pore structures and water adsorbed to all particle surfaces will release when exposed to vacuum. Early vacuum testing has shown that this gas release can occur violently, which loosens and weakens the simulant, altering the consolidation state. The Vacuum Facility #13, a mid-size chamber (3.66m tall, 1.5m inner diameter) at the NASA Glenn Research Center has been modified to create a soil mechanics test facility. A 0.64m deep by 0.914m square metric ton bed of lunar simulant was placed under vacuum using a variety of pumping techniques. Both GRC-3 and LHT-3M simulant types have been used. An electric cone penetrometer was used to measure simulant strength properties at vacuum including: cohesion, friction angle, bulk density and shear modulus. Simulant disruptions, caused by off gassing, affected the strength properties, but could be mitigated by reducing pump rate. No disruptions were observed at pressures below 2.5Torr, regardless of the pump rate. However, slow off gassing of the soil lead to long test times, a full week, to reach 10-5Torr. This work highlights the need for robotic machine-simulant hardware and operations in vacuum to expeditiously perform (sub-)systems tests.

  6. Development and Testing of an ISRU Soil Mechanics Vacuum Test Facility

    NASA Technical Reports Server (NTRS)

    Kleinhenz, Julie E.; Wilkinson, R. Allen

    2014-01-01

    For extraterrestrial missions, earth based testing in relevant environments is key to successful hardware development. This is true for both early component level development and system level integration. For In-Situ Resource Utilization (ISRU) on the moon, hardware must interface with the surface material, or regolith, in a vacuum environment. A relevant test environment will therefore involve a vacuum chamber with a controlled, properly conditioned bed of lunar regolith simulant. However, in earth-based granular media, such as lunar regolith simulant, gases trapped within the material pore structures and water adsorbed to all particle surfaces will release when exposed to vacuum. Early vacuum testing has shown that this gas release can occur violently, which loosens and weakens the simulant, altering the consolidation state. A mid-size chamber (3.66 m tall, 1.5 m inner diameter) at the NASA Glenn Research Center has been modified to create a soil mechanics test facility. A 0.64 m deep by 0.914 m square metric ton bed of lunar simulant was placed under vacuum using a variety of pumping techniques. Both GRC-3 and LHT-3M simulant types were used. Data obtained from an electric cone penetrometer can be used to determine strength properties at vacuum including: cohesion, friction angle, bulk density and shear modulus. Simulant disruptions, caused by off-gassing, affected the strength properties, but could be mitigated by reducing pump rate. No disruptions were observed at pressures below 2.5 Torr, regardless of the pump rate. The slow off-gassing of the soil at low pressure lead to long test times; a full week to reach 10(exp -5) Torr. Robotic soil manipulation would enable multiple ISRU hardware test within the same vacuum cycle. The feasibility of a robotically controlled auger and tamper was explored at vacuum conditions.

  7. Proton pump inhibitors

    MedlinePlus

    Proton pump inhibitors (PPIs) are medicines that work by reducing the amount of stomach acid made by ... Proton pump inhibitors are used to: Relieve symptoms of acid reflux, or gastroesophageal reflux disease (GERD). This ...

  8. Sizing pumps for slurries

    SciTech Connect

    Akhtar, S.Z.

    1996-11-01

    Slurry characteristics have a significant impact on centrifugal pump performance. For instance, as particle size increases or the percent solids concentration increases, pump head and efficiency decrease. Therefore, before a slurry pump is selected, it is important to define the slurry characteristics as accurately as possible. The effect of the slurry characteristics on the head and efficiency of the centrifugal pump will be emphasized (the effect on flowrate is less significant). The effect of slurry characteristics is more predominant in smaller pumps (with smaller diameter impellers) than in larger pumps. The data and relationship between the various slurry parameters have been developed from correlations and nomographs published by pump vendors from their field data and test results. The information helps to avoid specifying an undersized pump/motor assembly for slurry service.

  9. Insulin pump (image)

    MedlinePlus

    The catheter at the end of the insulin pump is inserted through a needle into the abdominal ... with diabetes. Dosage instructions are entered into the pump's small computer and the appropriate amount of insulin ...

  10. Liquid metal enabled pump

    PubMed Central

    Tang, Shi-Yang; Khoshmanesh, Khashayar; Sivan, Vijay; Petersen, Phred; O’Mullane, Anthony P.; Abbott, Derek; Mitchell, Arnan; Kalantar-zadeh, Kourosh

    2014-01-01

    Small-scale pumps will be the heartbeat of many future micro/nanoscale platforms. However, the integration of small-scale pumps is presently hampered by limited flow rate with respect to the input power, and their rather complicated fabrication processes. These issues arise as many conventional pumping effects require intricate moving elements. Here, we demonstrate a system that we call the liquid metal enabled pump, for driving a range of liquids without mechanical moving parts, upon the application of modest electric field. This pump incorporates a droplet of liquid metal, which induces liquid flow at high flow rates, yet with exceptionally low power consumption by electrowetting/deelectrowetting at the metal surface. We present theory explaining this pumping mechanism and show that the operation is fundamentally different from other existing pumps. The presented liquid metal enabled pump is both efficient and simple, and thus has the potential to fundamentally advance the field of microfluidics. PMID:24550485

  11. [Laser-induced breakdown spectroscopy system for elements analysis in high-temperature and vacuum environment].

    PubMed

    Pan, Cong-Yuan; Du, Xue-Wei; An, Ning; Han, Zhen-Yu; Wang, Sheng-Bo; Wei, Wei; Wang, Qiu-Ping

    2013-12-01

    Laser-induced breakdown spectroscopy (LIBS) is one of the most promising technologies to be applied to metallurgical composition online monitoring in these days. In order to study the spectral characters of LIBS spectrum and to investigate the quantitative analysis method of material composition under vacuum and high temperature environment, a LIBS measurement system was designed and set up which can be used for conducting experiments with high-temperature or molten samples in different vacuum environment. The system consists of a Q-switched Nd : YAG laser used as the light source, lens with different focus lengths used for laser focusing and spectrum signal collecting, a spectrometer used for detecting the signal of LIBS spectrums, and a vacuum system for holding and heating the samples while supplying a vacuum environment. The vacuum was achieved and maintained by a vacuum pump and an electric induction furnace was used for heating the system. The induction coil was integrated to the vacuum system by attaching to a ceramic sealing flange. The system was installed and testified, and the results indicate that the vacuum of the system can reach 1X 10(-4) Pa without heating, while the heating temperature could be about 1 600 degreeC, the system can be used for melting metal samples such as steel and aluminum and get the LIBS spectrum of the samples at the same time. Utilizing this system, LIBS experiments were conducted using standard steel samples under different vacuum or high-temperature conditions. Results of comparison between LIBS spectrums of solid steel samples under different vacuum were achieved, and so are the spectrums of molten and solid steel samples under vacuum environment. Through data processing and theoretical analyzing of these spectrums, the initial results of those experiments are in good agreement with the results that are presently reported, which indicates that the whole system functions well and is available for molten metal LIBS experiment

  12. Photovoltaic pump systems

    NASA Astrophysics Data System (ADS)

    Klockgether, J.; Kiessling, K. P.

    1983-09-01

    Solar pump systems for the irrigation of fields and for water supply in regions with much sunshine are discussed. For surface water and sources with a hoisting depth of 12 m, a system with immersion pumps is used. For deep sources with larger hoisting depths, an underwater motor pump was developed. Both types of pump system meet the requirements of simple installation and manipulation, safe operation, maintenance free, and high efficiency reducing the number of solar cells needed.

  13. Commissioning of the vacuum system of the KATRIN Main Spectrometer

    NASA Astrophysics Data System (ADS)

    Arenz, M.; Babutzka, M.; Bahr, M.; Barrett, J. P.; Bauer, S.; Beck, M.; Beglarian, A.; Behrens, J.; Bergmann, T.; Besserer, U.; Blümer, J.; Bodine, L. I.; Bokeloh, K.; Bonn, J.; Bornschein, B.; Bornschein, L.; Büsch, S.; Burritt, T. H.; Chilingaryan, S.; Corona, T. J.; De Viveiros, L.; Doe, P. J.; Dragoun, O.; Drexlin, G.; Dyba, S.; Ebenhöch, S.; Eitel, K.; Ellinger, E.; Enomoto, S.; Erhard, M.; Eversheim, D.; Fedkevych, M.; Felden, A.; Fischer, S.; Formaggio, J. A.; Fränkle, F.; Furse, D.; Ghilea, M.; Gil, W.; Glück, F.; Gonzalez Ureña, A.; Görhardt, S.; Groh, S.; Grohmann, S.; Grössle, R.; Gumbsheimer, R.; Hackenjos, M.; Hannen, V.; Harms, F.; Haußmann, N.; Heizmann, F.; Helbing, K.; Herz, W.; Hickford, S.; Hilk, D.; Hillen, B.; Höhn, T.; Holzapfel, B.; Hötzel, M.; Howe, M. A.; Huber, A.; Jansen, A.; Kernert, N.; Kippenbrock, L.; Kleesiek, M.; Klein, M.; Kopmann, A.; Kosmider, A.; Kovalík, A.; Krasch, B.; Kraus, M.; Krause, H.; Krause, M.; Kuckert, L.; Kuffner, B.; La Cascio, L.; Lebeda, O.; Leiber, B.; Letnev, J.; Lobashev, V. M.; Lokhov, A.; Malcherek, E.; Mark, M.; Martin, E. L.; Mertens, S.; Mirz, S.; Monreal, B.; Müller, K.; Neuberger, M.; Neumann, H.; Niemes, S.; Noe, M.; Oblath, N. S.; Off, A.; Ortjohann, H.-W.; Osipowicz, A.; Otten, E.; Parno, D. S.; Plischke, P.; Poon, A. W. P.; Prall, M.; Priester, F.; Ranitzsch, P. C.-O.; Reich, J.; Rest, O.; Robertson, R. G. H.; Röllig, M.; Rosendahl, S.; Rupp, S.; Ryšavý, M.; Schlösser, K.; Schlösser, M.; Schönung, K.; Schrank, M.; Schwarz, J.; Seiler, W.; Seitz-Moskaliuk, H.; Sentkerestiová, J.; Skasyrskaya, A.; Slezák, M.; Špalek, A.; Steidl, M.; Steinbrink, N.; Sturm, M.; Suesser, M.; Telle, H. H.; Thümmler, T.; Titov, N.; Tkachev, I.; Trost, N.; Unru, A.; Valerius, K.; Vénos, D.; Vianden, R.; Vöcking, S.; Wall, B. L.; Wandkowsky, N.; Weber, M.; Weinheimer, C.; Weiss, C.; Welte, S.; Wendel, J.; Wierman, K. L.; Wilkerson, J. F.; Winzen, D.; Wolf, J.; Wüstling, S.; Zacher, M.; Zadoroghny, S.; Zbořil, M.

    2016-04-01

    The KATRIN experiment will probe the neutrino mass by measuring the β-electron energy spectrum near the endpoint of tritium β-decay. An integral energy analysis will be performed by an electro-static spectrometer (``Main Spectrometer''), an ultra-high vacuum vessel with a length of 23.2 m, a volume of 1240 m3, and a complex inner electrode system with about 120 000 individual parts. The strong magnetic field that guides the β-electrons is provided by super-conducting solenoids at both ends of the spectrometer. Its influence on turbo-molecular pumps and vacuum gauges had to be considered. A system consisting of 6 turbo-molecular pumps and 3 km of non-evaporable getter strips has been deployed and was tested during the commissioning of the spectrometer. In this paper the configuration, the commissioning with bake-out at 300 °C, and the performance of this system are presented in detail. The vacuum system has to maintain a pressure in the 10-11 mbar range. It is demonstrated that the performance of the system is already close to these stringent functional requirements for the KATRIN experiment, which will start at the end of 2016.

  14. The vacuum system for the Munich fission fragment accelerator

    NASA Astrophysics Data System (ADS)

    Maier-Komor, P.; Faestermann, T.; Krücken, R.; Nebel, F.; Winkler, S.; Groß, M.; Habs, D.; Kester, O.; Szerypo, J.; Thirolf, P. G.

    2006-05-01

    The Munich Accelerator for Fission Fragments (MAFF) is a radioactive ion beam facility which will be installed at the new research reactor FRM-II. This new reactor became critical in Spring 2004. The heart of MAFF, the target-ion source unit will be placed in the through-going beam tube of the FRM-II. This beam tube has been installed, tested and filled with helium in 2001. The cogent authorization procedures and safety levels developed for nuclear power plants are applied for this research reactor also. Therefore, MAFF also has to obey these very strict rules, because the typical 1 g load of 235U in the MAFF source creates a fission product activity of several 10 14 Bq after one reactor cycle of 52 days. All vacuum components must withstand a pressure of 6×10 5 Pa in addition to their UHV acceptability. Even dynamic gaskets must be strictly metallic, because organic compounds would not withstand the radioactive irradiation during the design lifetime of 30 years. Only dry vacuum pumps are suitable: refrigerator cryopumps for the high-vacuum part and five stages of roots pumps for roughing and regeneration.

  15. Commissioning of the vacuum system of the KATRIN Main Spectrometer

    DOE PAGES

    Arenz, M.; Babutzka, M.; Bahr, M.; ...

    2016-04-07

    The KATRIN experiment will probe the neutrino mass by measuring the β-electron energy spectrum near the endpoint of tritium β-decay. We performed an integral energy analysis by an electro-static spectrometer (``Main Spectrometer''), an ultra-high vacuum vessel with a length of 23.2 m, a volume of 1240 m3, and a complex inner electrode system with about 120 000 individual parts. The strong magnetic field that guides the β-electrons is provided by super-conducting solenoids at both ends of the spectrometer. Its influence on turbo-molecular pumps and vacuum gauges had to be considered. Furthermore, a system consisting of 6 turbo-molecular pumps and 3more » km of non-evaporable getter strips has been deployed and was tested during the commissioning of the spectrometer. In this paper the configuration, the commissioning with bake-out at 300 °C, and the performance of this system are presented in detail. The vacuum system has to maintain a pressure in the 10-11 mbar range. We demonstrated that the performance of the system is already close to these stringent functional requirements for the KATRIN experiment, which will start at the end of 2016.« less

  16. Commissioning of the vacuum system of the KATRIN Main Spectrometer

    SciTech Connect

    Arenz, M.; Babutzka, M.; Bahr, M.; Barrett, J. P.; Bauer, S.; Beck, M.; Beglarian, A.; Behrens, J.; Bergmann, T.; Besserer, U.; Blümer, J.; Bodine, L. I.; Bokeloh, K.; Bonn, J.; Bornschein, B.; Bornschein, L.; Büsch, S.; Burritt, T. H.; Chilingaryan, S.; Corona, T. J.; Viveiros, L. De; Doe, P. J.; Dragoun, O.; Drexlin, G.; Dyba, S.; Ebenhöch, S.; Eitel, K.; Ellinger, E.; Enomoto, S.; Erhard, M.; Eversheim, D.; Fedkevych, M.; Felden, A.; Fischer, S.; Formaggio, J. A.; Fränkle, F.; Furse, D.; Ghilea, M.; Gil, W.; Glück, F.; Ureña, A. Gonzalez; Görhardt, S.; Groh, S.; Grohmann, S.; Grössle, R.; Gumbsheimer, R.; Hackenjos, M.; Hannen, V.; Harms, F.; Haußmann, N.; Heizmann, F.; Helbing, K.; Herz, W.; Hickford, S.; Hilk, D.; Hillen, B.; Höhn, T.; Holzapfel, B.; Hötzel, M.; Howe, M. A.; Huber, A.; Jansen, A.; Kernert, N.; Kippenbrock, L.; Kleesiek, M.; Klein, M.; Kopmann, A.; Kosmider, A.; Kovalík, A.; Krasch, B.; Kraus, M.; Krause, H.; Krause, M.; Kuckert, L.; Kuffner, B.; Cascio, L. La; Lebeda, O.; Leiber, B.; Letnev, J.; Lobashev, V. M.; Lokhov, A.; Malcherek, E.; Mark, M.; Martin, E. L.; Mertens, S.; Mirz, S.; Monreal, B.; Müller, K.; Neuberger, M.; Neumann, H.; Niemes, S.; Noe, M.; Oblath, N. S.; Off, A.; Ortjohann, H. -W.; Osipowicz, A.; Otten, E.; Parno, D. S.; Plischke, P.; Poon, A. W. P.; Prall, M.; Priester, F.; Ranitzsch, P. C. -O.; Reich, J.; Rest, O.; Robertson, R. G. H.; Röllig, M.; Rosendahl, S.; Rupp, S.; Ryšavý, M.; Schlösser, K.; Schlösser, M.; Schönung, K.; Schrank, M.; Schwarz, J.; Seiler, W.; Seitz-Moskaliuk, H.; Sentkerestiová, J.; Skasyrskaya, A.; Slezák, M.; Špalek, A.; Steidl, M.; Steinbrink, N.; Sturm, M.; Suesser, M.; Telle, H. H.; Thümmler, T.; Titov, N.; Tkachev, I.; Trost, N.; Unru, A.; Valerius, K.; Vénos, D.; Vianden, R.; Vöcking, S.; Wall, B. L.; Wandkowsky, N.; Weber, M.; Weinheimer, C.; Weiss, C.; Welte, S.; Wendel, J.; Wierman, K. L.; Wilkerson, J. F.; Winzen, D.; Wolf, J.; Wüstling, S.; Zacher, M.; Zadoroghny, S.; Zbořil, M.

    2016-04-07

    The KATRIN experiment will probe the neutrino mass by measuring the β-electron energy spectrum near the endpoint of tritium β-decay. We performed an integral energy analysis by an electro-static spectrometer (``Main Spectrometer''), an ultra-high vacuum vessel with a length of 23.2 m, a volume of 1240 m3, and a complex inner electrode system with about 120 000 individual parts. The strong magnetic field that guides the β-electrons is provided by super-conducting solenoids at both ends of the spectrometer. Its influence on turbo-molecular pumps and vacuum gauges had to be considered. Furthermore, a system consisting of 6 turbo-molecular pumps and 3 km of non-evaporable getter strips has been deployed and was tested during the commissioning of the spectrometer. In this paper the configuration, the commissioning with bake-out at 300 °C, and the performance of this system are presented in detail. The vacuum system has to maintain a pressure in the 10-11 mbar range. We demonstrated that the performance of the system is already close to these stringent functional requirements for the KATRIN experiment, which will start at the end of 2016.

  17. Vacuum system for the LBL Advanced Light Source (ALS)

    SciTech Connect

    Kennedy, K.; Henderson, T.; Meneghetti, J. )

    1989-03-01

    A 1.5 to 1.9 GeV synchrotron light source is being built at LBL. The vacuum system is designed to permit most synchrotron photons to escape the electron channel and be absorbed in an antechamber. The gas generated by the photons hitting the absorbers in the antechambers will be pumped by titanium sublimation pumps located directly under the absorbers. The electron channel and the antechamber are connected by a 10-mm-high slot that offers good electrodynamic isolation of the two chambers of frequencies affecting the store electron orbit. Twelve 10-meter-long vessels constitute the vacuum chambers for all the lattice magnets. Each chamber will be machined from two thick plates of 5083-H321 aluminum and welded at the perimeter. Machining both the inside and outside of the vacuum chamber permits the use of complex and accurate surfaces. The use of thick plates allows flanges to be machined directly into the wall of each chamber, thus avoiding much welding. 1 ref., 3 figs.

  18. 49 CFR 570.56 - Vacuum brake assist unit and vacuum brake system.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 6 2011-10-01 2011-10-01 false Vacuum brake assist unit and vacuum brake system... Vehicles With GVWR of More Than 10,000 Pounds § 570.56 Vacuum brake assist unit and vacuum brake system. The following requirements apply to vehicles with vacuum brake assist units and vacuum brake...

  19. 49 CFR 570.56 - Vacuum brake assist unit and vacuum brake system.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 6 2014-10-01 2014-10-01 false Vacuum brake assist unit and vacuum brake system... Vehicles With GVWR of More Than 10,000 Pounds § 570.56 Vacuum brake assist unit and vacuum brake system. The following requirements apply to vehicles with vacuum brake assist units and vacuum brake...

  20. 49 CFR 570.56 - Vacuum brake assist unit and vacuum brake system.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 6 2013-10-01 2013-10-01 false Vacuum brake assist unit and vacuum brake system... Vehicles With GVWR of More Than 10,000 Pounds § 570.56 Vacuum brake assist unit and vacuum brake system. The following requirements apply to vehicles with vacuum brake assist units and vacuum brake...

  1. 49 CFR 570.56 - Vacuum brake assist unit and vacuum brake system.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 6 2010-10-01 2010-10-01 false Vacuum brake assist unit and vacuum brake system... Vehicles With GVWR of More Than 10,000 Pounds § 570.56 Vacuum brake assist unit and vacuum brake system. The following requirements apply to vehicles with vacuum brake assist units and vacuum brake...

  2. 49 CFR 570.56 - Vacuum brake assist unit and vacuum brake system.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 6 2012-10-01 2012-10-01 false Vacuum brake assist unit and vacuum brake system... Vehicles With GVWR of More Than 10,000 Pounds § 570.56 Vacuum brake assist unit and vacuum brake system. The following requirements apply to vehicles with vacuum brake assist units and vacuum brake...

  3. Rotary magnetic heat pump

    DOEpatents

    Kirol, L.D.

    1987-02-11

    A rotary magnetic heat pump constructed without flow seals or segmented rotor accomplishes recuperation and regeneration by using split flow paths. Heat exchange fluid pumped through heat exchangers and returned to the heat pump splits into two flow components: one flowing counter to the rotor rotation and one flowing with the rotation. 5 figs.

  4. Rotary magnetic heat pump

    DOEpatents

    Kirol, Lance D.

    1988-01-01

    A rotary magnetic heat pump constructed without flow seals or segmented rotor accomplishes recuperation and regeneration by using split flow paths. Heat exchange fluid pumped through heat exchangers and returned to the heat pump splits into two flow components: one flowing counter to the rotor rotation and one flowing with the rotation.

  5. Centrifugal main fuel pump

    SciTech Connect

    Cole, E.F.

    1986-08-26

    For a gas turbine power plant having a fuel supply and a fuel metering valve and variable geometry for the power plant including servo actuating mechanisms for the fuel metering valve and variable geometry, a fuel pumping system, is described to supply pressurized fuel for the servo actuating mechanisms and for the engine working fluid medium. The pumping system includes a centrifugal pump solely supplying the fuel to the fuel metering valve to be delivered to the power plant for its working fluid medium, a positive displacement pump in parallel with the centrifugal pump and solely to supply pressurized fuel to the servo actuating mechanisms for the fuel metering valve and for the variable geometry, and a boost pump means disposed in serial relationship with the positive displacement pump and the centrifugal pump for augmenting the pressure supplied by the positive displacement pump and the centrifugal pump during predetermined operating conditions of the power plant. The combined boost pump and centrifugal pump capability is sufficient to satisfy the vapor to liquid ratio requirements of the power during its entire operating envelope.

  6. Green pumped Alexandrite lasers

    NASA Astrophysics Data System (ADS)

    Kuper, Jerry W.; Brown, David C.

    2005-04-01

    Initial experiments with pulsed and CW pumping an alexandrite laser rod at 532 nm are presented. This pumping architecture holds promise for the production of scalable diode-pumped, tunable alexandrite laser systems operating in the near infrared (750 nm), and the ultraviolet (375 and 250 nm) spectral regions.

  7. Use of a vacuum-planar photodiode to drive an electro-optic Q switch directly.

    PubMed

    Stankov, K A; Milev, I Y

    1991-12-20

    A vacuum photodiode was used to drive a Pockels cell directly in an optical-feedback arrangement. This technique was used to achieve Q switching and a single-longitudinal-mode operation in a flash-lamp-pumped Nd:YAG laser. Synchronization within 2 ns with an external short-pulse laser source was demonstrated.

  8. From diffusion pumps to cryopumps: The conversion of GSFC's space environment simulator

    NASA Technical Reports Server (NTRS)

    Cary, Ron

    1992-01-01

    The SES (Space Environmental Simulator), largest of the Thermal Vacuum Facilities at The Goddard Space Flight Center, recently was converted from an oil diffusion pumped chamber to a Cryopumped chamber. This modification was driven by requirements of flight projects. The basic requirement was to retain or enhance the operational parameters of the chamber such as pumping speed, ultimate vacuum, pump down time, and thermal system performance. To accomplish this task, seventeen diffusion pumps were removed and replaced with eight 1.2 meter (48 inch) diameter cryopumps and one 0.5 meter (20 inch) turbomolecular pump. The conversion was accomplished with a combination of subcontracting and in-house efforts to maximize the efficiency of implementation.

  9. Vacuum Brazing of Accelerator Components

    NASA Astrophysics Data System (ADS)

    Singh, Rajvir; Pant, K. K.; Lal, Shankar; Yadav, D. P.; Garg, S. R.; Raghuvanshi, V. K.; Mundra, G.

    2012-11-01

    Commonly used materials for accelerator components are those which are vacuum compatible and thermally conductive. Stainless steel, aluminum and copper are common among them. Stainless steel is a poor heat conductor and not very common in use where good thermal conductivity is required. Aluminum and copper and their alloys meet the above requirements and are frequently used for the above purpose. The accelerator components made of aluminum and its alloys using welding process have become a common practice now a days. It is mandatory to use copper and its other grades in RF devices required for accelerators. Beam line and Front End components of the accelerators are fabricated from stainless steel and OFHC copper. Fabrication of components made of copper using welding process is very difficult and in most of the cases it is impossible. Fabrication and joining in such cases is possible using brazing process especially under vacuum and inert gas atmosphere. Several accelerator components have been vacuum brazed for Indus projects at Raja Ramanna Centre for Advanced Technology (RRCAT), Indore using vacuum brazing facility available at RRCAT, Indore. This paper presents details regarding development of the above mentioned high value and strategic components/assemblies. It will include basics required for vacuum brazing, details of vacuum brazing facility, joint design, fixturing of the jobs, selection of filler alloys, optimization of brazing parameters so as to obtain high quality brazed joints, brief description of vacuum brazed accelerator components etc.

  10. Testing of Performance of a Scroll Pump in Support of Improved Vapor Phase Catalytic Ammonia Removal (VPCAR) Mass Reduction

    NASA Technical Reports Server (NTRS)

    Nahra, Henry K.; Kraft, Thomas G.; Yee, Glenda F.; Jankovsky, Amy L.; Flynn, Michael

    2006-01-01

    This paper describes the results of ground testing of a scroll pump with a potential of being a substitute for the current vacuum pump of the Vapor Phase Catalytic Ammonia Reduction (VPCAR). Assessments of the pressure-time, pump-down time, pump power and the pump noise were made for three configurations of the pump the first of which was without the gas ballast, the second with the gas ballast installed but not operating and the third with the gas ballast operating. The tested scroll pump exhibited optimum characteristics given its mass and power requirements. The pump down time required to reach a pressure of 50 Torr ranged from 60 minutes without the ballast to about 120 minutes with the gas ballast operational. The noise emission and the pump power were assessed in this paper as well.

  11. Vacuum phenomenon: Clinical relevance.

    PubMed

    Gohil, Ishan; Vilensky, Joel A; Weber, Edward C

    2014-04-01

    Vacuum phenomenon (VP) is an anatomical entity of potential confusion in the diagnosis and evaluation of joint pathology. Observation of this phenomenon has been demonstrated on basic radiographs, computed tomography, and magnetic resonance imaging. Although VP is most often associated with degenerative joint disease, it is observed with other pathologies. Two problematic scenarios can occur: a false-positive diagnosis of serious pathology instead of benign VP and a false-negative diagnosis of benign VP with a more serious underlying process Despite this potential for confusion, criteria for distinguishing VP from other causes of joint pain and for evaluating a suspected case of VP have not been fully established. We reviewed the literature to determine underlying mechanism, symptomology, associated pathologies, and clinical importance of VP. The formation of VP can be explained by gas solubility, pressure-volume relationships, and human physiology. CT, GRE-MRI, and multipositional views are the best imaging studies to view VP. Although most cases of VP are benign, it can be associated with clinical signs and symptoms. VP outside the spine is an underreported finding on imaging studies. VP should be on the differential diagnosis for joint pain, especially in the elderly. We have proposed criteria for diagnosing VP and generated a basic algorithm for its workup. Underreporting of this phenomenon shows a lack of awareness of VP on the part of physicians. By identifying true anatomic VP, we can prevent harm from suboptimal treatment of patients.

  12. Compact vacuum insulation

    DOEpatents

    Benson, David K.; Potter, Thomas F.

    1992-01-01

    Improved compact insulation panel is provided which is comprised of two adjacent metal sheets spaced close together with a plurality of spherical, or other discretely shaped, glass or ceramic beads optimally positioned between the sheets to provide support and maintain the spacing between the metal sheets when the gases therebetween are evacuated to form a vacuum. These spherical glass beads provide the maximum support while minimizing thermal conductance. In its preferred embodiment; these two metal sheets are textured with ribs or concave protrusions in conjunction with the glass beads to maximize the structural integrity of the panels while increasing the spacing between beads, thereby reducing the number of beads and the number of thermal conduction paths. Glass or porcelain-enameled liners in combination with the glass spacers and metal sidewalls effectively decrease thermal conductivity, and variious laminates, including wood, porcelain-enameled metal, and others effectively increase the strength and insulation capabilities of the panels. Also, a metal web is provided to hold the spacers in place, and strategic grooves are shown to accommodate expansion and contraction or shaping of the panels.

  13. Compact vacuum insulation

    DOEpatents

    Benson, D.K.; Potter, T.F.

    1992-10-27

    Improved compact insulation panel is provided which is comprised of two adjacent metal sheets spaced close together with a plurality of spherical, or other discretely shaped, glass or ceramic beads optimally positioned between the sheets to provide support and maintain the spacing between the metal sheets when the gases there between are evacuated to form a vacuum. These spherical glass beads provide the maximum support while minimizing thermal conductance. In its preferred embodiment; these two metal sheets are textured with ribs or concave protrusions in conjunction with the glass beads to maximize the structural integrity of the panels while increasing the spacing between beads, thereby reducing the number of beads and the number of thermal conduction paths. Glass or porcelain-enameled liners in combination with the glass spacers and metal sidewalls effectively decrease thermal conductivity, and various laminates, including wood, porcelain-enameled metal, and others effectively increase the strength and insulation capabilities of the panels. Also, a metal web is provided to hold the spacers in place, and strategic grooves are shown to accommodate expansion and contraction or shaping of the panels. 35 figs.

  14. Quantum Vacuum Pathway Theory

    NASA Astrophysics Data System (ADS)

    Habegger, Eric John

    2005-02-01

    It is theorized that the quantum vacuum is a random electromagnetic field that permeates the universe. It will be shown that acceleration between a quark and a random electromagnetic energy field is an analog of the reaction between a charge moving at constant velocity with respect to an organized electromagnetic field. The difference is that with a quark any natural perpendicular deflection during that motion, as predicted by Lorentz, is contained by the strong force, which results in a change in the angular momentum of the spin of a quark. The first derivative of the equations of motion of charges in an organized electromagnetic field may be used when applied to a random electromagnetic field to invoke the same fields modeled by Maxwell's equations. Mass is intimately bound up with a quark's spin angular momentum and the energy for that increase comes directly from the local field. The underlying randomness of the local field normally remains intact through these energy exchanges but it is speculated that in a quantum entanglement, an absolute level of order is imposed on the field along a path between two particles. This causes the non local effects seen in quantum entanglement. The mechanism that may cause this effect is discussed and a simple experiment is proposed that can test the hypothesis. Also discussed are new theoretical constructs for electromagnetic radiation, mass, the skin effect, self-inductance, superposition, and gravity. The emphasis will be on an intuitive and logical approach more than a mathematical approach.

  15. Simultaneous experimental generation of vacuum squeezing and bright amplitude squeezing from a frequency doubler.

    PubMed

    Luo, Yu; Li, Ying; Xie, Changde; Pan, Qing; Peng, Kunchi

    2005-06-15

    Both vacuum-squeezed and bright amplitude-squeezed states of light are experimentally generated from a frequency doubler with a semimonolithic Fabry-Perot configuration consisting of a type II nonlinear crystal and a concave mirror. Vacuum squeezing of 3.2 +/- 0.1 dB and amplitude squeezing of 1.3 +/- 0.2 dB are obtained simultaneously at a pump power of 8 mW. The two quadrature-squeezed optical fields that are generated are of identical frequency at 1080-nm wavelength and orthogonal polarization. Optimizing the input pump power by 19 mW yields as much as 5.0 +/- 0.2 dB of maximum vacuum squeezing. The advantages of the system are its simplicity and multiple utility.

  16. Liquid metal electric pump

    DOEpatents

    Abbin, Joseph P.; Andraka, Charles E.; Lukens, Laurance L.; Moreno, James B.

    1992-01-01

    An electrical pump for pumping liquid metals to high pressures in high temperature environments without the use of magnets or moving mechanical parts. The pump employs a non-porous solid electrolyte membrane, typically ceramic, specific to the liquid metal to be pumped. A DC voltage is applied across the thickness of the membrane causing ions to form and enter the membrane on the electrically positive surface, with the ions being neutralized on the opposite surface. This action provides pumping of the liquid metal from one side of the non-porous solid electrolyte membrane to the other.

  17. Jet pump assisted artery

    NASA Technical Reports Server (NTRS)

    1975-01-01

    A procedure for priming an arterial heat pump is reported; the procedure also has a means for maintaining the pump in a primed state. This concept utilizes a capillary driven jet pump to create the necessary suction to fill the artery. Basically, the jet pump consists of a venturi or nozzle-diffuser type constriction in the vapor passage. The throat of this venturi is connected to the artery. Thus vapor, gas, liquid, or a combination of the above is pumped continuously out of the artery. As a result, the artery is always filled with liquid and an adequate supply of working fluid is provided to the evaporator of the heat pipe.

  18. Thermal vacuum integrated system test at B-2

    NASA Astrophysics Data System (ADS)

    Kudlac, M. T.; Weaver, H. F.; Cmar, M. D.

    2012-04-01

    The National Aeronautics and Space Administration (NASA) Glenn Research Center (GRC) Plum Brook Station (PBS) Space Propulsion Research Facility, commonly referred to as B-2, is NASA's third largest thermal vacuum facility. It is the largest designed to store and transfer large quantities of liquid hydrogen and liquid oxygen, and is perfectly suited to support developmental testing of chemical propulsion systems as well as fully integrated stages. The facility is also capable of providing thermal-vacuum simulation services to support testing of large lightweight structures, Cryogenic Fluid Management (CFM) systems, electric propulsion test programs, and other In-Space propulsion programs. A recently completed integrated system test demonstrated the refurbished thermal vacuum capabilities of the facility. The test used the modernized data acquisition and control system to monitor the facility during pump down of the vacuum chamber, operation of the liquid nitrogen heat sink (or cold wall) and the infrared lamp array. A vacuum level of 1.3 × 10-4 Pa (1 × 10-6 torr) was achieved. The heat sink provided a uniform temperature environment of approximately 77 K (139°R) along the entire inner surface of the vacuum chamber. The recently rebuilt and modernized infrared lamp array produced a nominal heat flux of 1.4 kW/m2 at a chamber diameter of 6.7 m (22 ft) and along 11 m (36 ft) of the chamber's cylindrical vertical interior. With the lamp array and heat sink operating simultaneously, the thermal systems produced a heat flux pattern simulating radiation to space on one surface and solar exposure on the other surface. The data acquired matched pretest predictions and demonstrated system functionality.

  19. Sealing Materials for Use in Vacuum at High Temperatures

    NASA Technical Reports Server (NTRS)

    Pettit, Donald R.; Camarda, Charles J.; Lee Vaughn, Wallace

    2012-01-01

    Sealing materials that can be applied and left in place in vacuum over a wide range of temperatures (especially temperatures of a few thousand degrees Celsius) have been conceived and investigated for potential utility in repairing thermal-protection tiles on the space shuttles in orbit before returning to Earth. These materials are also adaptable to numerous terrestrial applications that involve vacuum processing and/or repair of structures that must withstand high temperatures. These materials can be formulated to have mechanical handling characteristics ranging from almost freely flowing liquid-like consistency through paste-like consistency to stiff puttylike consistency, and to retain these characteristics in vacuum until heated to high curing temperatures. A sealing material of this type can be formulated to be used in any of several different ways for example, to be impregnated into a high-temperature-fabric patch, impregnated into a high-temperature-fabric gasket for sealing a patch, applied under a patch, or applied alone in the manner of putty or wallboard compound. The sealing material must be formulated to be compatible with, and adhere to, the structural material(s) to be repaired. In general, the material consists of a vacuum-compatible liquid containing one or more dissolved compound(s) and/or mixed with suspended solid particles. Depending on the intended application, the liquid can be chosen to be of a compound that can remain in place in vacuum for a time long enough to be useful, and/or to evaporate or decompose in a controlled way to leave a useful solid residue behind. The evaporation rate is determined by proper choice of vapor pressure, application of heat, and/or application of ultraviolet light or other optical radiation. The liquid chosen for the original space shuttle application is a commercial silicone vacuum-pump oil.

  20. Thermal Vacuum Integrated System Test at B-2

    NASA Technical Reports Server (NTRS)

    Kudlac, Maureen T.; Weaver, Harold F.; Cmar, Mark D.

    2012-01-01

    The National Aeronautics and Space Administration (NASA) Glenn Research Center (GRC) Plum Brook Station (PBS) Space Propulsion Research Facility, commonly referred to as B-2, is NASA s third largest thermal vacuum facility. It is the largest designed to store and transfer large quantities of liquid hydrogen and liquid oxygen, and is perfectly suited to support developmental testing of chemical propulsion systems as well as fully integrated stages. The facility is also capable of providing thermal-vacuum simulation services to support testing of large lightweight structures, Cryogenic Fluid Management (CFM) systems, electric propulsion test programs, and other In-Space propulsion programs. A recently completed integrated system test demonstrated the refurbished thermal vacuum capabilities of the facility. The test used the modernized data acquisition and control system to monitor the facility during pump down of the vacuum chamber, operation of the liquid nitrogen heat sink (or cold wall) and the infrared lamp array. A vacuum level of 1.3x10(exp -4)Pa (1x10(exp -6)torr) was achieved. The heat sink provided a uniform temperature environment of approximately 77 K (140deg R) along the entire inner surface of the vacuum chamber. The recently rebuilt and modernized infrared lamp array produced a nominal heat flux of 1.4 kW/sq m at a chamber diameter of 6.7 m (22 ft) and along 11 m (36 ft) of the chamber s cylindrical vertical interior. With the lamp array and heat sink operating simultaneously, the thermal systems produced a heat flux pattern simulating radiation to space on one surface and solar exposure on the other surface. The data acquired matched pretest predictions and demonstrated system functionality.

  1. Photoelectron backscattering in vacuum phototubes

    NASA Astrophysics Data System (ADS)

    Lubsandorzhiev, B. K.; Vasiliev, R. V.; Vyatchin, Y. E.; Shaibonov, B. A. J.

    2006-11-01

    In this article we describe results of studies of a photoelectron backscattering effect in vacuum phototubes: classical photomultipliers (PMT) and hybrid phototubes (PH). Late pulses occurring in PMTs are attributed to the photoelectron backscattering and distinguished from pulses due to an anode glow effect. The late pulses are measured in a number of PMTs and HPs with various photocathode sizes covering 1 50 cm range and different types of the first dynode materials and construction designs. It is shown that the late pulses are a generic feature of all vacuum photodetectors—PMTs and PHs—and they do not deteriorate dramatically amplitude and timing responses of vacuum phototubes.

  2. Fluid sampling pump

    SciTech Connect

    Allen, P.V.; Nimberger, S.M.; Ward, R.L.

    1992-03-03

    This patent describes a pump for pumping a preselected quantity of fluid with each pump driving stroke from a fluid inlet port to a fluid outlet port, an inlet valve for selectively controlling fluid flow through the fluid inlet port, a pump body defining a pump bore therein, a piston slidably movable within the pump bore and having a fluid inlet end and an opposing operator end, an operator unit for reciprocating the piston within the pump bore, and a manifold interconnect with the pump body. It comprises a flow path therein extending from a manifold inlet port to a manifold outlet port, flow path being in communication with the fluid outlet port in the pump body, a purge passageway extending from the flow path to the outlet passageway, a purge valve for regulating fluid flow through the purge passageway, and a filter positioned within the manifold and extending across a portion of the flow path, the filter defining a filtered zone within the flow path adjoining the inlet port in the pump body, and an unfiltered zone within the flow path extending from the manifold inlet to the manifold outlet, such that filtered fluid enters the pump bore while unfiltered fluid bypasses the filter and passes out the manifold outlet port.

  3. A highly miniaturized vacuum package for a trapped ion atomic clock

    NASA Astrophysics Data System (ADS)

    Schwindt, Peter D. D.; Jau, Yuan-Yu; Partner, Heather; Casias, Adrian; Wagner, Adrian R.; Moorman, Matthew; Manginell, Ronald P.; Kellogg, James R.; Prestage, John D.

    2016-05-01

    We report on the development of a highly miniaturized vacuum package for use in an atomic clock utilizing trapped ytterbium-171 ions. The vacuum package is approximately 1 cm3 in size and contains a linear quadrupole RF Paul ion trap, miniature neutral Yb sources, and a non-evaporable getter pump. We describe the fabrication process for making the Yb sources and assembling the vacuum package. To prepare the vacuum package for ion trapping, it was evacuated, baked at a high temperature, and then back filled with a helium buffer gas. Once appropriate vacuum conditions were achieved in the package, it was sealed with a copper pinch-off and was subsequently pumped only by the non-evaporable getter. We demonstrated ion trapping in this vacuum package and the operation of an atomic clock, stabilizing a local oscillator to the 12.6 GHz hyperfine transition of 171Y b+. The fractional frequency stability of the clock was measured to be 2 × 10-11/τ1/2.

  4. Design of the vacuum system for the elliptical multipole wiggler at the Advanced Photon Source

    NASA Astrophysics Data System (ADS)

    Den Hartog, P.; Grimmer, J.; Klippert, T.; Trakhtenberg, E.; Xu, S.

    1996-09-01

    A vacuum system for the Advanced Photon Source elliptical multipole wiggler (EMW) that will operate at a pressure of 10-9 Torr with a storage ring current of 100 mA at 7.0 GeV has been designed and is being fabricated. The major part of the system is a stainless steel chamber with a 66.6 mm by 19.6 mm rectangular cross section. The length of the vacuum chamber is 3100 mm, and the wall thickness is 1.2 mm. Two versions of the vacuum chamber will be produced: with and without distributed nonevaporable getter (NEG) pumping. The version with NEG pumping will have slides on the top and bottom walls to accommodate sintered plates available from SAES. To activate these plates, the entire vacuum chamber will be baked from the outside up to a temperature of 350° C-450 °C. Provision for the baking is included in the design of the vacuum system, its support, and in the EMW itself. The complexity introduced into the design by the need for external activation of the NEG plates is eliminated in the design of the second version of the chamber. In this chamber, a sufficiently low outgassing rate may be achieved by extensive surface cleaning and baking in a vacuum furnace (10-6 Torr) up to a temperature of 950 ° C as has been achieved at the ESRF. Both versions are being pursued in parallel.

  5. A highly miniaturized vacuum package for a trapped ion atomic clock

    DOE PAGES

    Schwindt, Peter D. D.; Jau, Yuan-Yu; Partner, Heather; ...

    2016-05-12

    We report on the development of a highly miniaturized vacuum package for use in an atomic clock utilizing trapped ytterbium-171 ions. The vacuum package is approximately 1 cm3 in size and contains a linear quadrupole RF Paul ion trap, miniature neutral Yb sources, and a non-evaporable getter pump. We describe the fabrication process for making the Yb sources and assembling the vacuum package. To prepare the vacuum package for ion trapping, it was evacuated, baked at a high temperature, and then back filled with a helium buffer gas. Once appropriate vacuum conditions were achieved in the package, the package wasmore » sealed with a copper pinch-off and was then pumped only by the non-evaporable getter. We demonstrated ion trapping in this vacuum package and the operation of an atomic clock, stabilizing a local oscillator to the 12.6 GHz hyperfine transition of 171Yb+. The fractional frequency stability of the clock was measured to be 2 × 10-11 / τ1/2.« less

  6. A highly miniaturized vacuum package for a trapped ion atomic clock

    SciTech Connect

    Schwindt, Peter D. D.; Jau, Yuan-Yu; Partner, Heather; Casias, Adrian; Wagner, Adrian R.; Moorman, Matthew; Manginell, Ronald P.; Kellogg, James R.; Prestage, John D.

    2016-05-12

    We report on the development of a highly miniaturized vacuum package for use in an atomic clock utilizing trapped ytterbium-171 ions. The vacuum package is approximately 1 cm3 in size and contains a linear quadrupole RF Paul ion trap, miniature neutral Yb sources, and a non-evaporable getter pump. We describe the fabrication process for making the Yb sources and assembling the vacuum package. To prepare the vacuum package for ion trapping, it was evacuated, baked at a high temperature, and then back filled with a helium buffer gas. Once appropriate vacuum conditions were achieved in the package, the package was sealed with a copper pinch-off and was then pumped only by the non-evaporable getter. We demonstrated ion trapping in this vacuum package and the operation of an atomic clock, stabilizing a local oscillator to the 12.6 GHz hyperfine transition of 171Yb+. The fractional frequency stability of the clock was measured to be 2 × 10-11 / τ1/2.

  7. Vacuum high-harmonic generation and electromagnetic shock

    NASA Astrophysics Data System (ADS)

    Böhl, P.; King, B.; Ruhl, H.

    2016-04-01

    > When one takes into account the presence of virtual charged states in the quantum vacuum, a nonlinear self-interaction can arise in the propagation of electromagnetic fields. This self-interaction is often referred to as `real photon-photon scattering'. When the centre-of-mass energy of colliding photons is much lower than the rest energy of an electron-positron pair, this quantum effect can be included in the classical field equations of motion as a vacuum current and charge density using the Heisenberg-Euler Lagrangian. Using analytical and numerical methods for subcritical fields, the intrinsic solution to Maxwell's equations has been found for counterpropagating probe and pump plane waves in the presence of vacuum four- and six-wave mixing. In the corresponding all-order solution for the scattered probe, a route to vacuum high-harmonic generation is identified in which a long phase length can compensate for the weakness of interacting fields. The resulting shocks in the probe carrier wave and envelope are studied for different parameter regimes and polarisation set-ups. In this special issue, we study two additional set-ups: that of a slowly varying single-cycle background to highlight the effect of an oscillating background on the probe harmonic spectrum, and that of a few-cycle probe to highlight the smoothing of the harmonic peaks produced by a wider spectrum of probe photons. We also correct sign errors in an earlier publication.

  8. Miniature reciprocating heat pumps and engines

    NASA Technical Reports Server (NTRS)

    Thiesen, Jack H. (Inventor); Willen, Gary S. (Inventor); Mohling, Robert A. (Inventor)

    2003-01-01

    The present invention discloses a miniature thermodynamic device that can be constructed using standard micro-fabrication techniques. The device can be used to provide cooling, generate power, compress gases, pump fluids and reduce pressure below ambient (operate as a vacuum pump). Embodiments of the invention relating to the production of a cooling effect and the generation of electrical power, change the thermodynamic state of the system by extracting energy from a pressurized fluid. Energy extraction is attained using an expansion process, which is as nearly isentropic as possible for the appropriately chosen fluid. An isentropic expansion occurs when a compressed gas does work to expand, and in the disclosed embodiments, the gas does work by overcoming either an electrostatic or a magnetic force.

  9. Probing vacuum birefringence using x-ray free electron and optical high-intensity lasers

    NASA Astrophysics Data System (ADS)

    Karbstein, Felix; Sundqvist, Chantal

    2016-07-01

    Vacuum birefringence is one of the most striking predictions of strong field quantum electrodynamics: Probe photons traversing a strong field region can indirectly sense the applied "pump" electromagnetic field via quantum fluctuations of virtual charged particles which couple to both pump and probe fields. This coupling is sensitive to the field alignment and can effectively result in two different indices of refraction for the probe photon polarization modes giving rise to a birefringence phenomenon. In this article, we perform a dedicated theoretical analysis of the proposed discovery experiment of vacuum birefringence at an x-ray free electron laser/optical high-intensity laser facility. Describing both pump and probe laser pulses realistically in terms of their macroscopic electromagnetic fields, we go beyond previous analyses by accounting for various effects not considered before in this context. Our study facilitates stringent quantitative predictions and optimizations of the signal in an actual experiment.

  10. Low-Dead-Volume Inlet for Vacuum Chamber

    NASA Technical Reports Server (NTRS)

    Naylor, Guy; Arkin, C.

    2011-01-01

    Gas introduction from near-ambient pressures to high vacuum traditionally is accomplished either by multi-stage differential pumping that allows for very rapid response, or by a capillary method that allows for a simple, single-stage introduction, but which often has a delayed response. Another means to introduce the gas sample is to use the multi-stage design with only a single stage. This is accomplished by using a very small conductance limit. The problem with this method is that a small conductance limit will amplify issues associated with dead-volume. As a result, a high-vacuum gas inlet was developed with low dead-volume, allowing the use of a very low conductance limit interface. Gas flows through the ConFlat flange at a relatively high flow rate at orders of magnitude greater than through the conductance limit. The small flow goes through a conductance limit that is a double-sided ConFlat.

  11. Low-Dead-Volume Inlet for Vacuum Chamber

    NASA Technical Reports Server (NTRS)

    Naylor, Guy; Arkin, C.

    2010-01-01

    Gas introduction from near-ambient pressures to high vacuum traditionally is accomplished either by multi-stage differential pumping that allows for very rapid response, or by a capillary method that allows for a simple, single-stage introduction, but which often has a delayed response. Another means to introduce the gas sample is to use the multi-stage design with only a single stage. This is accomplished by using a very small conductance limit. The problem with this method is that a small conductance limit will amplify issues associated with dead -volume. As a result, a high -vacuum gas inlet was developed with low dead -volume, allowing the use of a very low conductance limit interface. Gas flows through the ConFlat flange at a relatively high flow rate at orders of magnitude greater than through the conductance limit. The small flow goes through a conductance limit that is a double-sided ConFlat.

  12. Vacuum chamber with a supersonic-flow aerodynamic window

    DOEpatents

    Hanson, C.L.

    1980-10-14

    A supersonic flow aerodynamic window is disclosed whereby a steam ejector situated in a primary chamber at vacuum exhausts superheated steam toward an orifice to a region of higher pressure, creating a barrier to the gas in the region of higher pressure which attempts to enter through the orifice. In a mixing chamber outside and in fluid communication with the primary chamber, superheated steam and gas are combined into a mixture which then enters the primary chamber through the orifice. At the point of impact of the ejector/superheated steam and the incoming gas/superheated steam mixture, a barrier is created to the gas attempting to enter the ejector chamber. This barrier, coupled with suitable vacuum pumping means and cooling means, serves to keep the steam ejector and primary chamber at a negative pressure, even though the primary chamber has an orifice to a region of higher pressure.

  13. Vacuum chamber with a supersonic flow aerodynamic window

    DOEpatents

    Hanson, Clark L.

    1982-01-01

    A supersonic flow aerodynamic window, whereby a steam ejector situated in a primary chamber at vacuum exhausts superheated steam toward an orifice to a region of higher pressure, creating a barrier to the gas in the region of higher pressure which attempts to enter through the orifice. In a mixing chamber outside and in fluid communication with the primary chamber, superheated steam and gas are combined into a mixture which then enters the primary chamber through the orifice. At the point of impact of the ejector/superheated steam and the incoming gas/superheated steam mixture, a barrier is created to the gas attempting to enter the ejector chamber. This barrier, coupled with suitable vacuum pumping means and cooling means, serves to keep the steam ejector and primary chamber at a negative pressure, even though the primary chamber has an orifice to a region of higher pressure.

  14. Meeting today's requirements for large thermal vacuum test facilities

    NASA Technical Reports Server (NTRS)

    Corinth, R. L.; Rouse, J. A.

    1986-01-01

    The Lockheed Thermal Vacuum Facility at Sunnyvale, California, completed in late 1986, one of the largest multi-program facilities constructed to date is described. The horizontal 12.2 m diameter by 24.4 m long chamber has removable heads at each end and houses a thermal shroud providing a test volume 10.4 m diameter by 24.4 m long. The chamber and thermal shroud are configured to permit the insertion of a 6.1 m wide by 24.4 m long vibration isolated optical bench. The pumpimg system incorporates an internal cryopumping array, turbomolecular pumps and cryopumps to handle multi-program needs and ranges of gas loads. The high vacuum system is capable of achieving clean, dry and empty pressures below 1.3 times 10 to the minus 6 power Pa (10 to the minus 8 power torr.)

  15. Alumina barrier for vacuum brazing

    NASA Technical Reports Server (NTRS)

    Beuyukian, C. S.

    1980-01-01

    Heating platens of vacuum-brazing press will not stick to workpiece if aluminum oxide "paper" is interposed. Paper does not disintegrate in press, will not contaminate braze alloy, and helps form smoothly contoured, regular fillet at brazed edges.

  16. Vacuum lamination of photovoltaic modules

    NASA Technical Reports Server (NTRS)

    Burger, D. R.

    1982-01-01

    Vacuum lamination of terrestrial photovoltaic modules is a new high volume process requiring new equipment and newly develop materials. Equipment development, materials research, and some research in related fields and testing methods are discussed.

  17. IRIS Leaves Thermal Vacuum Chamber

    NASA Video Gallery

    This video shows the transportation of the IRIS observatory from the thermal vacuum chamber back to the clean tent for final testing and preparations for delivery to the launch site at Vandenberg A...

  18. [Endoscopic vacuum-assisted closure].

    PubMed

    Wedemeyer, J; Lankisch, T

    2013-03-01

    Anastomotic leakage in the upper and lower intestinal tract is associated with high morbidity and mortality. Within the last 10 years endoscopic treatment options have been accepted as sufficient treatment option of these surgical complications. Endoscopic vacuum assisted closure (E-VAC) is a new innovative endoscopic therapeutic option in this field. E-VAC transfers the positive effects of vacuum assisted closure (VAC) on infected cutaneous wounds to infected cavities that can only be reached endoscopically. A sponge connected to a drainage tube is endoscopically placed in the leakage and a continuous vacuum is applied. Sponge and vacuum allow removal of infected fluids and promote granulation of the leakage. This results in clean wound grounds and finally allows wound closure. Meanwhile the method was also successfully used in the treatment of necrotic pancreatitis.

  19. VACUUM DEPOSITION OF THIN FILMS,

    DTIC Science & Technology

    The book deals with methods of obtaining and processing thin films , methods of measuring the deposition rate and thickness of thin-film layers, and...the main fields of application of thin films . Vacuum requirements and the requirements for the composition of the residual medium in thermal...evaporation and cathode sputtering are given, and modern methods of producing and measuring vacuums and the equipment used in obtaining thin films are described. (Author)

  20. Technical specification for vacuum systems

    SciTech Connect

    Khaw, J.

    1987-01-01

    The vacuum systems at the Stanford Linear Accelerator Center (SLAC) are primarily of all-metal construction and operate at pressures from 10/sup -5/ to 10/sup -11/ Torr. The primary gas loads during operation result from thermal desorption and beam-induced desorption from the vacuum chamber walls. These desorption rates can be extremely high in the case of hydrocarbons and other contaminants. These specifications place a major emphasis on eliminating contamination sources. The specifications and procedures have been written to insure the cleanliness and vacuum integrity of all SLAC vacuum systems, and to assist personnel involved with SLAC vacuum systems in choosing and designing components that are compatible with existing systems and meet the quality and reliability of SLAC vacuum standards. The specification includes requirements on design, procurement, fabrication, chemical cleaning, clean room practices, welding and brazing, helium leak testing, residual gas analyzer testing, bakeout, venting, and pumpdown. Also appended are specifications regarding acceptable vendors, isopropyl alcohol, bakeable valve cleaning procedure, mechanical engineering safety inspection, notes on synchrotron radiation, and specifications of numerous individual components. (LEW)

  1. Cold cathode vacuum gauging system

    DOEpatents

    Denny, Edward C.

    2004-03-09

    A vacuum gauging system of the cold cathode type is provided for measuring the pressure of a plurality of separate vacuum systems, such as in a gas centrifuge cascade. Each casing is fitted with a gauge tube assembly which communicates with the vacuum system in the centrifuge casing. Each gauge tube contains an anode which may be in the form of a slender rod or wire hoop and a cathode which may be formed by the wall of the gauge tube. The tube is provided with an insulated high voltage connector to the anode which has a terminal for external connection outside the vacuum casing. The tube extends from the casing so that a portable magnet assembly may be inserted about the tube to provide a magnetic field in the area between the anode and cathode necessary for pressure measurements in a cold cathode-type vacuum gauge arrangement. The portable magnetic assembly is provided with a connector which engages the external high voltage terminal for providing power to the anode within in the gauge tube. Measurement is made in the same manner as the prior cold cathode gauges in that the current through the anode to the cathode is measured as an indication of the pressure. By providing the portable magnetic assembly, a considerable savings in cost, installation, and maintenance of vacuum gauges for pressure measurement in a gas centrifuge cascade is realizable.

  2. Pitot heat pump

    SciTech Connect

    Grose, R.D.

    1981-12-08

    A pitot heat pump is described wherein a multi-stage pitot pump is employed as the compression means in a heat pump thermodynamic cycle. The heat pump is comprised of a multi-stage vapor pitot pump, liquid pitot pump, turbine, vaporizer, evaporator, condenser and expansion valve. The turbine is used to rotate a shaft to which the impellers of the pitot pump are attached. Refrigerant gas from the evaporator enters the first stage of the pitot pump and the impeller therein forces the refrigerant gas outwardly where it enters the narrow end of a pitot tube provided therein. The discharge end of the pitot tube is in communication with the next stage of the pitot pump. In passing through the pitot tube, the refrigerant gas expands and the centrifugal force and the kinetic energy of the gas provide the energy whereby the refrigerant gas is compressed. After the last stage, the compressed gas is transmitted to the condenser of the heat pump.

  3. A study of the feasibility of mechanical pumps for use with the Pioneer-Venus probe mass spectrometer inlet system

    NASA Technical Reports Server (NTRS)

    Thomas, N. C.; Crosmer, W. E.; Nowak, D.

    1973-01-01

    A survey of mechanical vacuum pumps was completed. A small Roots blower for flight mass spectrometer applications was evaluated with respect to system operating parameters in a number of different modes of operation. The survey indicated that a metal bellows pump might be a viable alternative for the systems requirements. The results of the study are given, including current status of possible flight-type pumps, a systems analysis using available pumps, and recommendations for fabrication and tests of a potential flight-type pump.

  4. Improving the Bevatron vacuum to 10/sup -10/ torr

    SciTech Connect

    Avery, R.; Elioff, T.; Grunder, H.

    1981-03-01

    Pressure of approx. 10/sup -10/ torr is needed in the Bevatron to accelerate partially-stripped very-heavy ions (e.g. U/sup 69 +/) in the Bevatron without significant loss due to interactions with the residual gas. This ultra-high vacuum will be achieved by installing (summer and fall 1981) a cryogenic liner, mostly 12/sup 0/K, surrounding the Bevatron circulating beam. The novel construction features are presented along with results from successful tests of prototype sections. This is believed to be the largest application of cryogenic pumping to particle accelerators yet undertaken.

  5. Modeling of RHIC insulating vacuum for system pumpdown characteristics

    SciTech Connect

    Todd, R.J.; Pate, D.J.; Welch, K.M.

    1993-06-01

    This paper presents a model for predicting the pumpdown characteristics of a 480 m RHIC (Relativistic Heavy Ion Collider) vacuum cryostat. The longitudinal and transverse conductances of a typical cryostat were calculated. A voltage analogue of these conductances was constructed for room temperature conditions. The total longitudinal conductance of a room temperature cryostat was thereby achieved. This conductance was then used to calculate the diameter of an equivalent long outgassing tube, having more convenient analytical expressions for pressure profiles when pumped. The equivalent of a unit outgassing rate for this tube was obtained using previously published MLI (multi-layer insulation) outgassing data. With this model one is then able to predict a cryostat pumpdown rate as a function of the location and size of roughing pumps.

  6. Development of Sub-Ischial Prosthetic Sockets with Vacuum-Assisted Suspension for Highly Active Persons with Transfemoral Amputations

    DTIC Science & Technology

    2013-10-01

    Caldwell R , Hansen A, Fatone S (in press) Methods for Characterization of Mechanical and Electrical Prosthetic Vacuum Pumps. Journal of Rehabilitation...Research and Development, 50(8). Appendix E Komolafe O, Caldwell R , Fatone S (prepared) Finite Element Analysis of Rigid Frame Designs for...Design, in The Academy Today 2007. p. A7-9. 4 Fairley , M., ’Hanging Tight’: Elevated Vacuum Suspension Systems Step Forward, in The O&P Edge March

  7. Vacuum-Gauge Connection For Shipping Container

    NASA Technical Reports Server (NTRS)

    Henry, Robert H.

    1990-01-01

    External connector enables measurement of vacuum in stored part. Remote-readout connector added to shipping container and connected to thermo-couple vacuum gauge in vacuum-insulated cryogenic line packed in container. Enables monitoring of condition of vacuum without opening container.

  8. Pump isolation valve

    DOEpatents

    Kinney, Calvin L.; Wetherill, Todd M.

    1983-08-02

    The pump isolation valve provides a means by which the pump may be selectively isolated from the remainder of the coolant system while being compatible with the internal hydraulic arrangement of the pump during normal operation of the pump. The valve comprises a valve cylinder disposed around the pump and adjacent to the last pump diffuser with a turning vane attached to the lower end of the valve cylinder in a manner so as to hydraulically match with the discharge diffuser. The valve cylinder is connected to a drive means for sliding the valve cylinder relative to the diffuser support cylinder so as to block flow in either direction through the discharge diffuser when the valve is in the closed position and to aid in the flow of the coolant from the discharge diffuser by means of the turning vane when the valve is in the open position.

  9. DIRECT CURRENT ELECTROMAGNETIC PUMP

    DOEpatents

    Barnes, A.H.

    1957-11-01

    An improved d-c electromagnetic pump is presented in which the poles, and consequently the magetic gap at the poles, are tapered to be wider at the upstream end. In addition, the cross section of the tube carryiQ the liquid metal is tapered so that the velocity of the pumped liquid increases in the downstream direction at a rate such that the counter-induced voltage in the liquid metal remains constant as it traverses the region between the poles. This configuration compensates for the distortion of the magnetic field caused by the induced voltage that would otherwise result in the lowering of the pumping capacity. This improved electromagnetic pump as practical application in the pumping of liquid metal coolants for nuclear reactors where conventional positive displacement pumps have proved unsatisfactory due to the high temperatures and the corrosive properties of the liquid metals involved.

  10. Rotary blood pump

    NASA Technical Reports Server (NTRS)

    Bozeman, Richard J. (Inventor); Akkerman, James W. (Inventor); Aber, Greg S. (Inventor); Vandamm, George A. (Inventor); Bacak, James W. (Inventor); Svejkovsky, Paul A. (Inventor); Benkowski, Robert J. (Inventor)

    1993-01-01

    A rotary blood pump is presented. The pump includes a pump housing for receiving a flow straightener, a rotor mounted on rotor bearings and having an inducer portion and an impeller portion, and a diffuser. The entrance angle, outlet angle, axial, and radial clearances of the blades associated with the flow straightener, inducer portion, impeller portion, and diffuser are optimized to minimize hemolysis while maintaining pump efficiency. The rotor bearing includes a bearing chamber that is filled with crosslinked blood or other bio-compatible material. A back emf integrated circuit regulates rotor operation and a microcomputer may be used to control one or more back emf integrated circuits. A plurality of magnets are disposed in each of a plurality of impeller blades with a small air gap. A stator may be axially adjusted on the pump housing to absorb bearing load and maximize pump efficiency.

  11. Electrokinetic pumps and actuators

    SciTech Connect

    Phillip M. Paul

    2000-03-01

    Flow and ionic transport in porous media are central to electrokinetic pumping as well as to a host of other microfluidic devices. Electrokinetic pumping provides the ability to create high pressures (to over 10,000 psi) and high flow rates (over 1 mL/min) with a device having no moving parts and all liquid seals. The electrokinetic pump (EKP) is ideally suited for applications ranging from a high pressure integrated pump for chip-scale HPLC to a high flow rate integrated pump for forced liquid convection cooling of high-power electronics. Relations for flow rate and current fluxes in porous media are derived that provide a basis for analysis of complex microfluidic systems as well as for optimization of electrokinetic pumps.

  12. Vacuum space charge effects in sub-picosecond soft X-ray photoemission on a molecular adsorbate layer

    DOE PAGES

    Dell'Angela, M.; Anniyev, T.; Beye, M.; ...

    2015-03-01

    Vacuum space charge-induced kinetic energy shifts of O 1s and Ru 3d core levels in femtosecond soft X-ray photoemission spectra (PES) have been studied at a free electron laser (FEL) for an oxygen layer on Ru(0001). We fully reproduced the measurements by simulating the in-vacuum expansion of the photoelectrons and demonstrate the space charge contribution of the high-order harmonics in the FEL beam. Employing the same analysis for 400 nm pump-X-ray probe PES, we can disentangle the delay dependent Ru 3d energy shifts into effects induced by space charge and by lattice heating from the femtosecond pump pulse.

  13. Fakir fuel pump

    NASA Technical Reports Server (NTRS)

    1922-01-01

    In designing the Fakir fuel pump, the fundamental idea was to obtain a simple and reliable method of conveying the fuel from a low tank to the carburetor, with the avoidance of the faults of all former methods and the simultaneous warming of the fuel by means of the heat of compression generated. The principle of the Fakir fuel pump rests on the well-known principle of the diaphragm pump, which must be suitably adapted to the present purpose.

  14. A compact cryogenic pump

    NASA Astrophysics Data System (ADS)

    Li, Gang; Caldwell, Shane; Clark, Jason A.; Gulick, Sidney; Hecht, Adam; Lascar, Daniel D.; Levand, Tony; Morgan, Graeme; Orford, Rodney; Savard, Guy; Sharma, Kumar S.; Van Schelt, Jonathon

    2016-04-01

    A centrifugal cryogenic pump has been designed at Argonne National Laboratory to circulate liquid nitrogen (LN2) in a closed circuit allowing the recovery of excess fluid. The pump can circulate LN2 at rates of 2-10 L/min, into a head of 0.5-3 m. Over four years of laboratory use the pump has proven capable of operating continuously for 50-100 days without maintenance.

  15. Detection of pump degradation

    SciTech Connect

    Greene, R.H.; Casada, D.A.; Ayers, C.W.

    1995-08-01

    This Phase II Nuclear Plant Aging Research study examines the methods of detecting pump degradation that are currently employed in domestic and overseas nuclear facilities. This report evaluates the criteria mandated by required pump testing at U.S. nuclear power plants and compares them to those features characteristic of state-of-the-art diagnostic programs and practices currently implemented by other major industries. Since the working condition of the pump driver is crucial to pump operability, a brief review of new applications of motor diagnostics is provided that highlights recent developments in this technology. The routine collection and analysis of spectral data is superior to all other technologies in its ability to accurately detect numerous types and causes of pump degradation. Existing ASME Code testing criteria do not require the evaluation of pump vibration spectra but instead overall vibration amplitude. The mechanical information discernible from vibration amplitude analysis is limited, and several cases of pump failure were not detected in their early stages by vibration monitoring. Since spectral analysis can provide a wealth of pertinent information concerning the mechanical condition of rotating machinery, its incorporation into ASME testing criteria could merit a relaxation in the monthly-to-quarterly testing schedules that seek to verify and assure pump operability. Pump drivers are not included in the current battery of testing. Operational problems thought to be caused by pump degradation were found to be the result of motor degradation. Recent advances in nonintrusive monitoring techniques have made motor diagnostics a viable technology for assessing motor operability. Motor current/power analysis can detect rotor bar degradation and ascertain ranges of hydraulically unstable operation for a particular pump and motor set. The concept of using motor current or power fluctuations as an indicator of pump hydraulic load stability is presented.

  16. Ionization-Assisted Getter Pumping for Ultra-Stable Trapped Ion Frequency Standards

    NASA Technical Reports Server (NTRS)

    Tjoelker, Robert L.; Burt, Eric A.

    2010-01-01

    A method eliminates (or recovers from) residual methane buildup in getter-pumped atomic frequency standard systems by applying ionizing assistance. Ultra-high stability trapped ion frequency standards for applications requiring very high reliability, and/or low power and mass (both for ground-based and space-based platforms) benefit from using sealed vacuum systems. These systems require careful material selection and system processing (cleaning and high-temperature bake-out). Even under the most careful preparation, residual hydrogen outgassing from vacuum chamber walls typically limits the base pressure. Non-evaporable getter pumps (NEGs) provide a convenient pumping option for sealed systems because of low mass and volume, and no power once activated. An ion gauge in conjunction with a NEG can be used to provide a low mass, low-power method for avoiding the deleterious effects of methane buildup in high-performance frequency standard vacuum systems.

  17. In Vitro Testing of a Novel Blood Pump Designed for Temporary Extracorporeal Support

    PubMed Central

    Spurlock, DJ; Ranney, DN; Fracz, E; Mazur, DE; Bartlett, RH; Haft, JW

    2012-01-01

    Extracorporeal blood pumps are used as temporary ventricular assist devices or for extracorporeal membrane oxygenation. The ideal pump would be intrinsically self-regulating, carry no risk of cavitation or excessive inlet suction, be afterload insensitive, and valveless thus reducing thrombogenicity. Currently used technology, including roller, centrifugal, and pneumatic pulsatile pumps, does not meet these requirements. We studied a non-occlusive peristaltic pump (M-Pump) in two mock circulatory loops, and compared the performance to a frequently used centrifugal pump and a modified prototype of the M-Pump (the BioVAD). The simple resistance loop consisted of the investigated pump, a fixed height reservoir at 150 mmHg, and a variable inflow reservoir. The pulsatile circulation utilized a mock patient simulator with adjustable resistance elements connected to a pneumatic pulsatile pump. The M-Pump intrinsically regulated flow with changing preload, was afterload insensitive, and did not cavitate, unlike the centrifugal pump. The BioVAD also demonstrated these features, and could augment output with use of vacuum assistance. A non-occlusive peristaltic pump may be superior for short term extracorporeal circulatory assist by mitigating risks of excessive inlet suction, afterload sensitivity, and thrombosis. PMID:22236624

  18. In vitro testing of a novel blood pump designed for temporary extracorporeal support.

    PubMed

    Spurlock, David J; Ranney, David N; Fracz, Emilia M; Mazur, Daniel E; Bartlet, R H; Haft, Jonathan W

    2012-01-01

    Extracorporeal blood pumps are used as temporary ventricular assist devices or for extracorporeal membrane oxygenation. The ideal pump would be intrinsically self-regulating, carry no risk of cavitation or excessive inlet suction, be afterload insensitive, and valveless thus reducing thrombogenicity. Currently used technology, including roller, centrifugal, and pneumatic pulsatile pumps, does not meet these requirements. We studied a nonocclusive peristaltic pump (M-Pump) in two mock circulatory loops and compared the performance to a frequently used centrifugal pump and a modified prototype of the M-Pump (the BioVAD). The simple resistance loop consisted of the investigated pump, a fixed height reservoir at 150 mm Hg, and a variable inflow reservoir. The pulsatile circulation used a mock patient simulator with adjustable resistance elements connected to a pneumatic pulsatile pump. The M-Pump intrinsically regulated flow with changing preload, was afterload insensitive, and did not cavitate, unlike the centrifugal pump. The BioVAD also demonstrated these features and could augment output with the use of vacuum assistance. A nonocclusive peristaltic pump may be superior for short-term extracorporeal circulatory assist by mitigating risks of excessive inlet suction, afterload sensitivity, and thrombosis.

  19. Solar heated vacuum pyrolysis of lunar soil

    NASA Astrophysics Data System (ADS)

    Sauerborn, M.; Neumann, A.; Seboldt, W.; Diekmann, B.

    The goal of the project is the thermal reduction of samples of lunar regolith simulant as a possible technique for producing oxygen by pyrolysis on a lunar base. The extraterrestrial production of oxygen is a key technology for a lunar base or manned missions to near-Earth asteroids or Mars. The solar heated vacuum pyrolysis has some important advantages, because it is based upon the realities of the lunar environment. As a tool for investigating the basic reactions and the technology the DLR High Flux Solar Furnace was used. This facility is operated since 1994 in Cologne. It delivers concentrated solar radiation up to a peak flux of 5 MW/m2. This power can be used to cause thermal or photochemical effects in irradiated materials. For the astrophysical and mineralogical applications discussed here, a vacuum chamber with a solar-adapted design and new instrumentation was developed. The pyrolysis experiments were conducted under high vacuum. Using the concentrated beam of the solar furnace as heat source, the lunar soil simulant samples achieved liquid phase in 10 - 20 seconds and reached temperatures between 1500 to 1900 K, were the relevant processes took place. The heating phase was followed by a controlled cooling. The partial pressure of oxygen and several other constituents in the vapour phase was measured with a differentially pumped quadrupole mass spectrometer. The temperatures of the samples were measured by an IR camera with a special optical system. Baseline experiments with different reference metal oxides like SiO2, CaO, and ZnO were made to verify the apparatus and investigate background contamination. The data of the five experiments with regolith showed typical features and a similar behaviour of gas partial pressure depending on temperature level, with an increase of oxygen during the strongest irradiation. The detected oxygen originates from thermal decomposition of the mineral sample and caused a large numbers of gas bubbles inside the melt

  20. Champagne Heat Pump

    NASA Technical Reports Server (NTRS)

    Jones, Jack A.

    2004-01-01

    The term champagne heat pump denotes a developmental heat pump that exploits a cycle of absorption and desorption of carbon dioxide in an alcohol or other organic liquid. Whereas most heat pumps in common use in the United States are energized by mechanical compression, the champagne heat pump is energized by heating. The concept of heat pumps based on other absorption cycles energized by heat has been understood for years, but some of these heat pumps are outlawed in many areas because of the potential hazards posed by leakage of working fluids. For example, in the case of the water/ammonia cycle, there are potential hazards of toxicity and flammability. The organic-liquid/carbon dioxide absorption/desorption cycle of the champagne heat pump is similar to the water/ammonia cycle, but carbon dioxide is nontoxic and environmentally benign, and one can choose an alcohol or other organic liquid that is also relatively nontoxic and environmentally benign. Two candidate nonalcohol organic liquids are isobutyl acetate and amyl acetate. Although alcohols and many other organic liquids are flammable, they present little or no flammability hazard in the champagne heat pump because only the nonflammable carbon dioxide component of the refrigerant mixture is circulated to the evaporator and condenser heat exchangers, which are the only components of the heat pump in direct contact with air in habitable spaces.

  1. Submersible sodium pump

    DOEpatents

    Brynsvold, G.V.; Lopez, J.T.; Olich, E.E.; West, C.W.

    1989-11-21

    An electromagnetic submerged pump has an outer cylindrical stator with an inner cylindrical conductive core for the submerged pumping of sodium in the cylindrical interstitial volume defined between the stator and core. The cylindrical interstitial volume is typically vertically oriented, and defines an inlet at the bottom and an outlet at the top. The outer stator generates upwardly conveyed toroidal magnetic fields, which fields convey preferably from the bottom of the pump to the top of the pump liquid sodium in the cold leg of a sodium cooled nuclear reactor. The outer cylindrical stator has a vertically disposed duct surrounded by alternately stacked layers of coil units and laminates. 14 figs.

  2. Submersible sodium pump

    DOEpatents

    Brynsvold, Glen V.; Lopez, John T.; Olich, Eugene E.; West, Calvin W.

    1989-01-01

    An electromagnetic submerged pump has an outer cylindrical stator with an inner cylindrical conductive core for the submerged pumping of sodium in the cylindrical interstitial volume defined between the stator and core. The cylindrical interstitial volume is typically vertically oriented, and defines an inlet at the bottom and an outlet at the top. The outer stator generates upwardly conveyed toroidal magnetic fields, which fields convey preferably from the bottom of the pump to the top of the pump liquid sodium in the cold leg of a sodium cooled nuclear reactor. The outer cylindrical stator has a vertically disposed duct surrounded by alternately stacked layers of coil units and laminates.

  3. Fuel injection pump

    SciTech Connect

    Miyaki, M.

    1986-01-07

    This patent describes a fuel injection pump for delivering fuel to the cylinders of an internal combustion engine consisting of: a pump housing with a fuel chamber therein to which fuel is supplied from a fuel tank; means for compressing fuel in the pump chamber and delivering the compressed fuel to the engine cylinders with such means including a pump plunger adapted to be reciprocated so as to introduce fuel into the pump chamber and to pressurize the introduced fuel; spill means for spilling to a low-pressure side on a fuel tank side the compressed fuel which was pressurized in the pump chamber to be delivered from the pump chamber to the engine cylinders, the spill mechanism including a spill passage communicating with the pump chamber and including a solenoid valve located in the spill passage for opening and closing the spill passage with predetermined timing; escape for allowing the compressed fuel pressurized in the pump chamber to escape to the low-pressure side of the fuel tank side.

  4. Remotely operable peristaltic pump

    NASA Technical Reports Server (NTRS)

    Belew, R. R. (Inventor)

    1986-01-01

    A peristaltic pump is disclosed which includes a roller assembly on which is mounted a series of pump rollers. As the roller assembly is rotated by a drive gear the pump rollers are driven in reverse rotation by means of a stationary ring gear and pump roller gears. An upper pressure shoe plate and a lower pressure shoe plate are positioned above sets of flexible tubing. The tubing is sandwiched between the pressure shoe plates and the pump rollers. A highly compact pump is provided having twice as many fluid channel lines as is conventional. The peristaltic pump device may be remotely operated by means of a rotary actuator which rotates a driving hub to move the shoe plates by means of eccentrically mounted links. The pressure shoe plates may be moved by the rotary actuator to a loaded position in which the fluid lines are pinched by the pump rollers and fluid is pumped to an unloaded position in which the fluid lines are maintained in an undeformed, uncrimped configuration so that no creases or crimps are set into the fluid lines during periods of prolonged nonuse.

  5. Thermomechanical piston pump development

    NASA Technical Reports Server (NTRS)

    Sabelman, E. E.

    1971-01-01

    A thermally powered reciprocating pump has been devised to replace or augment an electric pump for the transport of temperature-control fluid on the Thermoelectric Outer Planet Spacecraft (TOPS). The thermally powered pump operates cyclically by extracting heat energy from the fluid by means of a vapor-pressure expansion system and by using the heat to perform the mechanical work of pumping. A feasibility test unit has been constructed to provide an output of 7 cu in during a 10- to 100-second cycle. It operates with a fluid input temperature of 200 to 300 F and a heat sink temperature of 0 to 30 F.

  6. [Portable peristaltic perfusion pumps].

    PubMed

    Magallón Pedrera, I; Soto Torres, I

    1999-11-01

    Portable peristaltic perfusion pumps allow one to administer pharmaceuticals in hospitals as well as in primary health care centers and furthermore these pumps present multiple advantages for patients and their families since they make it possible to carry out treatment in a patient's home while at the same time lowering the costs involved. The authors analyze the most out standing aspects of portable peristaltic perfusion pumps along with their characteristics, installation, programming, and how to turn them on; in addition, the authors list the maintenance care which these pumps require.

  7. Detection of pump degradation

    SciTech Connect

    Casada, D.

    1995-04-01

    There are a variety of stressors that can affect the operation of centrifugal pumps. Although these general stressors are active in essentially all centrifugal pumps, the stressor level and the extent of wear and degradation can vary greatly. Parameters that affect the extent of stressor activity are manifold. In order to assure the long-term operational readiness of a pump, it is important to both understand the nature and magnitude of the specific degradation mechanisms and to monitor the performance of the pump. The most commonly applied method of monitoring the condition of not only pumps, but rotating machinery in general, is vibration analysis. Periodic or continuous special vibration analysis is a cornerstone of most pump monitoring programs. In the nuclear industry, non-spectral vibration monitoring of safety-related pumps is performed in accordance with the ASME code. Pump head and flow rate are also monitored, per code requirements. Although vibration analysis has dominated the condition monitoring field for many years, there are other measures that have been historically used to help understand pump condition; advances in historically applied technologies and developing technologies offer improved monitoring capabilities. The capabilities of several technologies (including vibration analysis, dynamic pressure analysis, and motor power analysis) to detect the presence and magnitude of both stressors and resultant degradation are discussed.

  8. Vacuum Packaging for Microelectromechanical Systems (MEMS)

    DTIC Science & Technology

    2002-10-01

    The Vacuum Packaging for MEMS Program focused on the development of an integrated set of packaging technologies which in totality provide a low cost...high volume product-neutral vacuum packaging capability which addresses all MEMS vacuum packaging requirements. The program balanced the need for...near term component and wafer-level vacuum packaging with the development of advanced high density wafer-level packaging solutions. Three vacuum

  9. Probability distribution of the vacuum energy density

    SciTech Connect

    Duplancic, Goran; Stefancic, Hrvoje; Glavan, Drazen

    2010-12-15

    As the vacuum state of a quantum field is not an eigenstate of the Hamiltonian density, the vacuum energy density can be represented as a random variable. We present an analytical calculation of the probability distribution of the vacuum energy density for real and complex massless scalar fields in Minkowski space. The obtained probability distributions are broad and the vacuum expectation value of the Hamiltonian density is not fully representative of the vacuum energy density.

  10. Resonance wave pumping: wave mass transport pumping

    NASA Astrophysics Data System (ADS)

    Carmigniani, Remi; Violeau, Damien; Gharib, Morteza

    2016-11-01

    It has been previously reported that pinching at intrinsic resonance frequencies a valveless pump (or Liebau pump) results in a strong pulsating flow. A free-surface version of the Liebau pump is presented. The experiment consists of a closed tank with a submerged plate separating the water into a free-surface and a recirculation section connected through two openings at each end of the tank. A paddle is placed at an off-centre position at the free-surface and controlled in a heaving motion with different frequencies and amplitudes. Near certain frequencies identified as resonance frequencies through a linear potential theory analysis, the system behaves like a pump. Particle Image Velocimetry (PIV) is performed in the near free surface region and compared with simulations using Volume of Fluid (VOF) method. The mean eulerian mass flux field (ρ) is extracted. It is observed that the flow is located in the vicinity of the surface layer suggesting Stokes Drift (or Wave Mass Transport) is the source of the pumping. A model is developped to extend the linear potential theory to the second order to take into account these observations. The authors would like to acknowledge the Gordon and Betty Moore Foundation for their generous support.

  11. Well-pump alignment system

    DOEpatents

    Drumheller, Douglas S.

    1998-01-01

    An improved well-pump for geothermal wells, an alignment system for a well-pump, and to a method for aligning a rotor and stator within a well-pump, wherein the well-pump has a whistle assembly formed at a bottom portion thereof, such that variations in the frequency of the whistle, indicating misalignment, may be monitored during pumping.

  12. Liquid pump for astronaut cooling

    NASA Technical Reports Server (NTRS)

    Carson, M. A.

    1972-01-01

    The Apollo portable life support system water-recirculation pump used for astronaut cooling is described. The problems associated with an early centrifugal pump and how these problems were overcome by the use of a new diaphragm pump are discussed. Performance comparisons of the two pump designs are given. Developmental problems and flight results with the diaphragm pump are discussed.

  13. Measurement of partial pressures in vacuum technology and vacuum physics

    NASA Technical Reports Server (NTRS)

    Huber, W. K.

    1986-01-01

    It is pointed out that the measurement of gaseous pressures of less than 0.0001 torr is based on the ionization of gas atoms and molecules due to collisions with electrons. The particle density is determined in place of the pressure. The ionization cross sections for molecules of various gases are discussed. It is found that the true pressure in a vacuum system cannot be determined with certainty if it is unknown which gas is present. Effects of partial pressure determination on the condition of the vacuum system are discussed together with ion sources, systems of separation, and ion detection.

  14. Vacuum-assisted cesarean section

    PubMed Central

    McQuivey, Ross W; Block, Jon E

    2017-01-01

    There has been a dramatic rise in the frequency of cesarean sections, surpassing 30% of all deliveries in the US. This upsurge, coupled with a decreasing willingness to allow vaginal birth after cesarean section, has resulted in an expansion of the use of vacuum assistance to safely extract the fetal head. By avoiding the use of a delivering hand or forceps blade, the volume being delivered through the uterine incision can be decreased when the vacuum is used properly. Reducing uterine extensions with their associated complications (eg, excessive blood loss) in difficult cases is also a theoretical advantage of vacuum delivery. Maternal discomfort related to excessive fundal pressure may also be lessened. To minimize the risk of neonatal morbidity, proper cup placement over the “flexion point” remains essential to maintain vacuum integrity and reduce the chance of inadvertent detachment and uterine extensions. Based on the published literature and pragmatic clinical experience, utilization of the vacuum device is a safe and effective technique to assist delivery during cesarean section. PMID:28331371

  15. Looking south at boiler feedwater pumps (steam turbine pump on ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Looking south at boiler feedwater pumps (steam turbine pump on left, electric motor pump on right). - Wheeling-Pittsburgh Steel Corporation, Allenport Works, Boiler House, Route 88 on West bank of Monongahela River, Allenport, Washington County, PA

  16. 98. VIEW OF PUMPS FROM NORTH. MILL SOLUTION PUMP No. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    98. VIEW OF PUMPS FROM NORTH. MILL SOLUTION PUMP No. 2 IN FOREGROUND, ABANDONED BARREN SOLUTION PUMP BEYOND. AGITATOR No. 1 IN BACKGROUND. - Bald Mountain Gold Mill, Nevada Gulch at head of False Bottom Creek, Lead, Lawrence County, SD

  17. 33. PLAN OF DEER ISLAND PUMPING STATION SHOWING EXISTING PUMPING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    33. PLAN OF DEER ISLAND PUMPING STATION SHOWING EXISTING PUMPING PLAN AND LOCATION OF PROPOSED ADDITIONS, METROPOLITAN WATER AND SEWERAGE BOARD, METROPOLITAN SEWERAGE WORKS, JULY 1908. Aperture card 6417. - Deer Island Pumping Station, Boston, Suffolk County, MA

  18. A vacuum disengager for tritium removal from HYLIFE-II Reactor Flibe

    SciTech Connect

    Dolan, T.J.; Longhurst, G.R.; Garcia-Otero, E.

    1992-09-01

    We have designed a vacuum disengager system to remove tritium from the Flibe (Li{sub 2}BeF{sub 4}) molten salt coolant of the HYLIFE-II fusion reactor. There is a two-stage vacuum disengager in each of three intermediate heat exchanger (IHX) loops. Each stage consists of a vacuum chamber 4 m in diameter and 7 m tall. As 0.2 mm diameter molten salt droplets fall vertically downward into the vacuum, most of the tritium diffuses out of the droplets and is pumped away. A fraction {Phi} {approximately}10{sup {minus}5} of the 8.6 MCi/day tritium source (from breeding in the Flibe and from unburned fuel) remains in the Flibe as it leaves the vacuum disengagers, and about 21% of that permeates into the intermediate coolant loop, so about 20 Ci/day leak into the steam system. With Flibe primary coolant and a vacuum disengager, it appears that an intermediate coolant loop is not needed to prevent tritium from leaking into the steam system. An experiment is needed to demonstrate Flibe vacuum disengager operation.

  19. A vacuum disengager for tritium removal from HYLIFE-II Reactor Flibe

    SciTech Connect

    Dolan, T.J.; Longhurst, G.R. ); Garcia-Otero, E. . Dept. of Nuclear Engineering)

    1992-01-01

    We have designed a vacuum disengager system to remove tritium from the Flibe (Li{sub 2}BeF{sub 4}) molten salt coolant of the HYLIFE-II fusion reactor. There is a two-stage vacuum disengager in each of three intermediate heat exchanger (IHX) loops. Each stage consists of a vacuum chamber 4 m in diameter and 7 m tall. As 0.2 mm diameter molten salt droplets fall vertically downward into the vacuum, most of the tritium diffuses out of the droplets and is pumped away. A fraction {Phi} {approximately}10{sup {minus}5} of the 8.6 MCi/day tritium source (from breeding in the Flibe and from unburned fuel) remains in the Flibe as it leaves the vacuum disengagers, and about 21% of that permeates into the intermediate coolant loop, so about 20 Ci/day leak into the steam system. With Flibe primary coolant and a vacuum disengager, it appears that an intermediate coolant loop is not needed to prevent tritium from leaking into the steam system. An experiment is needed to demonstrate Flibe vacuum disengager operation.

  20. Gravity-Induced Vacuum Dominance

    SciTech Connect

    Lima, William C. C.; Vanzella, Daniel A. T.

    2010-04-23

    It has been widely believed that, except in very extreme situations, the influence of gravity on quantum fields should amount to just small, subdominant contributions. This view seemed to be endorsed by the seminal results obtained over the last decades in the context of renormalization of quantum fields in curved spacetimes. Here, however, we argue that this belief is false by showing that there exist well-behaved spacetime evolutions where the vacuum energy density of free quantum fields is forced, by the very same background spacetime, to become dominant over any classical energy-density component. By estimating the time scale for the vacuum energy density to become dominant, and therefore for backreaction on the background spacetime to become important, we argue that this (infrared) vacuum dominance may bear unexpected astrophysical and cosmological implications.

  1. Gravity-induced vacuum dominance.

    PubMed

    Lima, William C C; Vanzella, Daniel A T

    2010-04-23

    It has been widely believed that, except in very extreme situations, the influence of gravity on quantum fields should amount to just small, subdominant contributions. This view seemed to be endorsed by the seminal results obtained over the last decades in the context of renormalization of quantum fields in curved spacetimes. Here, however, we argue that this belief is false by showing that there exist well-behaved spacetime evolutions where the vacuum energy density of free quantum fields is forced, by the very same background spacetime, to become dominant over any classical energy-density component. By estimating the time scale for the vacuum energy density to become dominant, and therefore for backreaction on the background spacetime to become important, we argue that this (infrared) vacuum dominance may bear unexpected astrophysical and cosmological implications.

  2. Microscale Digital Vacuum Electronic Gates

    NASA Technical Reports Server (NTRS)

    Manohara, Harish (Inventor); Mojarradi, Mohammed M. (Inventor)

    2014-01-01

    Systems and methods in accordance with embodiments of the invention implement microscale digital vacuum electronic gates. In one embodiment, a microscale digital vacuum electronic gate includes: a microscale field emitter that can emit electrons and that is a microscale cathode; and a microscale anode; where the microscale field emitter and the microscale anode are disposed within at least a partial vacuum; where the microscale field emitter and the microscale anode are separated by a gap; and where the potential difference between the microscale field emitter and the microscale anode is controllable such that the flow of electrons between the microscale field emitter and the microscale anode is thereby controllable; where when the microscale anode receives a flow of electrons, a first logic state is defined; and where when the microscale anode does not receive a flow of electrons, a second logic state is defined.

  3. Pump apparatus including deconsolidator

    DOEpatents

    Sonwane, Chandrashekhar; Saunders, Timothy; Fitzsimmons, Mark Andrew

    2014-10-07

    A pump apparatus includes a particulate pump that defines a passage that extends from an inlet to an outlet. A duct is in flow communication with the outlet. The duct includes a deconsolidator configured to fragment particle agglomerates received from the passage.

  4. A Shocking New Pump

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Hydro Dynamics, Inc. received a technical helping hand from NASA that made their Hydrosonic Pump (HPump) a reality. Marshall engineers resolved a bearing problem in the rotor of the pump and recommended new bearings, housings and mounting hardware as a solution. The resulting HPump is able to heat liquids with greater energy efficiency using shock waves to generate heat.

  5. Detection of pump degradation

    SciTech Connect

    Casada, D.

    1994-12-31

    There are a variety of stressors that can affect the operation of centrifugal pumps. Although these general stressors are active in essentially all centrifugal pumps, the stressor level and the extent of wear and degradation can vary greatly. Parameters that affect the extent of stressor activity are manifold. In order to assure the long-term operational readiness of a pump, it is important to both understand the nature and magnitude of the specific degradation mechanisms and to monitor the performance of the pump. The most commonly applied method of monitoring the condition of not only pumps, but rotating machinery in general, is vibration analysis. Periodic or continuous spectral vibration analysis is a cornerstone of most pump monitoring programs. In the nuclear industry, non-spectral vibration monitoring of safety-related pumps is performed in accordance with the ASME code. Although vibration analysis has dominated the condition monitoring field for many years, there are other measures that have been historically used to help understand pump condition: advances in historically applied technologies and developing technologies offer improved monitoring capabilities. The capabilities of several technologies (including vibration analysis, dynamic pressure analysis, and motor power analysis) to detect the presence and magnitude of both stressors and resultant degradation are discussed.

  6. Micromachined peristaltic pumps

    NASA Technical Reports Server (NTRS)

    Hartley, Frank T. (Inventor)

    1999-01-01

    Micromachined pumps including a channel formed between a first membrane and a substrate or between first and second flexible membranes. A series of electrically conductive strips is applied to a surface of the substrate or one of the membranes. Application of a sequential voltage to the series of strips causes a region of closure to progress down the channel to achieve a pumping action.

  7. Solar heat pump

    NASA Astrophysics Data System (ADS)

    Hermanson, R.

    Brief discussions of the major components of a solar powered, chemical ground source heat pump are presented. The components discussed are the solar collectors and the chemical heat storage battery. Sodium sulfide is the medium used for heat storage. Catalog information which provides a description of all of the heat pump systems is included.

  8. Estimating Pump Blockage

    NASA Technical Reports Server (NTRS)

    Chung, W.; Meng, S. Y.; Meng, C. Y.

    1984-01-01

    Blockage predicted for all components including inducers, impellers and diffusers. Pump performance predicted by semiempirical method shows excellent agreement with test results in Space Shuttle main-engine highpressure fuel turbopump. Comparisons of pump efficiency show equally good agreement of calculated values with experimental ones. Method improves current estimation methods based solely on subjective engineering judgment.

  9. Water Treatment Technology - Pumps.

    ERIC Educational Resources Information Center

    Ross-Harrington, Melinda; Kincaid, G. David

    One of twelve water treatment technology units, this student manual on pumps provides instructional materials for three competencies. (The twelve units are designed for a continuing education training course for public water supply operators.) The competencies focus on the following areas: types of pumps in plant and distribution systems, pump…

  10. NEUTRONIC REACTOR FUEL PUMP

    DOEpatents

    Cobb, W.G.

    1959-06-01

    A reactor fuel pump is described which offers long life, low susceptibility to radiation damage, and gaseous fission product removal. An inert-gas lubricated bearing supports a journal on one end of the drive shsft. The other end has an impeller and expansion chamber which effect pumping and gas- liquid separation. (T.R.H.)

  11. Advances in pump technology: insulin patch pumps, combined pumps and glucose sensors, and implanted pumps.

    PubMed

    Schaepelynck, P; Darmon, P; Molines, L; Jannot-Lamotte, M F; Treglia, C; Raccah, D

    2011-12-01

    This review discusses the most recent developments in insulin pump technology. The benefits of the insulin pump to patients with type 1 diabetes are recognized both for its metabolic effectiveness and its positive effects on quality of life. The current pumps are reliable, small and light, and are becoming more and more sophisticated. Nevertheless, there remain practical and psychological constraints for the patient. However, recent patch-pump advances should simplify the technical aspects of pump treatment and enhance patient comfort. Another advance combines the insulin pump with a glucose sensor. Such a combination is logical for optimizing pump use and, to that end, developing an automated or 'closed-loop'system that permits the delivery of subcutaneous insulin adjusted according to measured levels of subcutaneous glucose. Finally, implanted insulin pumps have proven their worth not only because of their simple use, but also for their contribution in the artificial pancreas project. Indeed, the prompt response with intraperitoneal administration of insulin makes it of interest for use in a closed-loop system.

  12. Custom Unit Pump Design and Testing for the EVA PLSS

    NASA Technical Reports Server (NTRS)

    Schuller, Michael; Kurwitz, Cable; Goldman, Jeff; Morris, Kim; Trevino, Luis

    2009-01-01

    This paper describes the effort by the Texas Engineering Experiment Station (TEES) and Honeywell for NASA to design and test a pre-flight prototype pump for use in the Extra-vehicular activity (EVA) portable life support subsystem (PLSS). Major design decisions were driven by the need to reduce the pump s mass, power, and volume compared to the existing PLSS pump. In addition, the pump must accommodate a much wider range of abnormal conditions than the existing pump, including vapor/gas bubbles and increased pressure drop when employed to cool two suits simultaneously. A positive displacement, external gear type pump was selected because it offers the most compact and highest efficiency solution over the required range of flow rates and pressure drops. An additional benefit of selecting a gear pump design is that it is self priming and capable of ingesting non-condensable gas without becoming air locked. The chosen pump design consists of a 28 V DC, brushless, sealless, permanent magnet motor driven, external gear pump that utilizes a Honeywell development that eliminates the need for magnetic coupling. Although the planned flight unit will use a sensorless motor with custom designed controller, the pre-flight prototype to be provided for this project incorporates Hall effect sensors, allowing an interface with a readily available commercial motor controller. This design approach reduced the cost of this project and gives NASA more flexibility in future PLSS laboratory testing. The pump design was based on existing Honeywell designs, but incorporated features specifically for the PLSS application, including all of the key features of the flight pump. Testing at TEES verified that the pump meets the design requirements for range of flow rates, pressure drop, power consumption, working fluid temperature, operating time, gas ingestion , and restart capability under both ambient and vacuum conditions. The pump operated between 40 and 240 lbm/hr flowrate, 35 to 100 F

  13. NOVEL CHAMBER DESIGN FOR AN IN-VACUUM CRYO-COOLED MINI-GAP UNDULATOR.

    SciTech Connect

    HU, J.-P.; FOERSTER, C.L.; SKARITKA, J.R.; WATERMAN, D.

    2006-05-24

    A stainless steel, Ultra-High Vacuum (UHV) chamber, featuring a large vertical rectangular port (53''W by 16''H), has been fabricated to house the one-meter magnet assembly of a newly installed undulator insertion device for beamline X-25 at the National Synchrotron Light Source. To achieve UHV, the new chamber is equipped with a differential ion pump, NEG pump, nude ion gauge, residual gas analyzer, and an all metal roughing valve. Temperature of the magnet assembly is maintained below 90 C during vacuum bake. The large rectangular port cover is sealed to the main flange of the chamber using a one-piece flat aluminum gasket and special sealing surfaces developed exclusively by Nor-Cal Products, Inc. The large flange provides easy access to the gap of the installed magnet girders for in situ magnetic measurements and shimming. Special window ports were designed into the cover and chamber for manipulation of optical micrometers external to the chamber to provide precise measurements of the in-vacuum magnet gap. The vacuum chamber assembly features independently vacuum-isolated feedthroughs that can be used for either water-or-cryogenic refrigeration-cooling of the monolithic magnet girders. This would allow for cryogenic-cooled permanent magnet operation and has been successfully tested within temperature range of +100 C to -150 C. Details of the undulator assembly for beamline X-25 is described in the paper.

  14. Normetex Pump Alternatives Study

    SciTech Connect

    Clark, Elliot A.

    2013-04-25

    A mainstay pump for tritium systems, the Normetex scroll pump, is currently unavailable because the Normetex company went out of business. This pump was an all-metal scroll pump that served tritium processing facilities very well. Current tritium system operators are evaluating replacement pumps for the Normetex pump and for general used in tritium service. An all-metal equivalent alternative to the Normetex pump has not yet been identified. 1. The ideal replacement tritium pump would be hermetically sealed and contain no polymer components or oils. Polymers and oils degrade over time when they contact ionizing radiation. 2. Halogenated polymers (containing fluorine, chlorine, or both) and oils are commonly found in pumps. These materials have many properties that surpass those of hydrocarbon-based polymers and oils, including thermal stability (higher operating temperature) and better chemical resistance. Unfortunately, they are less resistant to degradation from ionizing radiation than hydrocarbon-based materials (in general). 3. Polymers and oils can form gaseous, condensable (HF, TF), liquid, and solid species when exposed to ionizing radiation. For example, halogenated polymers form HF and HCl, which are extremely corrosive upon reaction with water. If a pump containing polymers or oils must be used in a tritium system, the system must be designed to be able to process the unwanted by-products. Design features to mitigate degradation products include filters and chemical or physical traps (eg. cold traps, oil traps). 4. Polymer components can work in tritium systems, but must be replaced regularly. Polymer components performance should be monitored or be regularly tested, and regular replacement of components should be viewed as an expected normal event. A radioactive waste stream must be established to dispose of used polymer components and oil with an approved disposal plan developed based on the facility location and its regulators. Polymers have varying

  15. New High Capacity Getter for Vacuum-Insulated Mobile Liquid Hydrogen Storage Systems

    SciTech Connect

    H. Londer; G. R. Myneni; P. Adderley; G. Bartlok; J. Setina; W. Knapp; D. Schleussner

    2006-05-01

    Current ''Non evaporable getters'' (NEGs), based on the principle of metallic surface sorption of gas molecules, are important tools for the improving the performance of many vacuum systems. High porosity alloys or powder mixtures of Zr, Ti, Al, V, Fe and other metals are the base materials for this type of getters. The continuous development of vacuum technologies has created new challenges for the field of getter materials. The main sorption parameters of the current NEGs, namely, pumping speed and sorption capacity, have reached certain upper limits. Chemically active metals are the basis of a new generation of NEGs. The introduction of these new materials with high sorption capacity at room temperature is a long-awaited development. These new materials enable the new generation of NEGs to reach faster pumping speeds, significantly higher sticking rates and sorption capacities up to 104 times higher during their lifetimes. Our development efforts focus on producing these chemically active metals with controlled insulation or protection. The main structural forms of our new getter materials are spherical powders, granules and porous multi-layers. The full pumping performance can take place at room temperature with activation temperatures ranging from room temperature to 650 C. In one of our first pilot projects, our proprietary getter solution was successfully introduced as a getter pump in a double-wall mobile LH2 tank system. Our getters were shown to have very high sorption capacity of all relevant residual gases, including H2. This new concept opens the opportunity for significant vacuum improvements, especially in the field of H2 pumping which is an important task in many different vacuum applications.

  16. New High Capacity Getter for Vacuum-Insulated Mobile Liquid Hydrogen Storage Systems

    NASA Astrophysics Data System (ADS)

    Londer, H.; Myneni, G. R.; Adderley, P.; Bartlok, G.; Setina, J.; Knapp, W.; Schleussner, D.

    2006-05-01

    Current "Non evaporable getters" (NEGs), based on the principle of metallic surface sorption of gas molecules, are important tools for the improving the performance of many vacuum systems. High porosity alloys or powder mixtures of Zr, Ti, Al, V, Fe and other metals are the base materials for this type of getters. The continuous development of vacuum technologies has created new challenges for the field of getter materials. The main sorption parameters of the current NEGs, namely, pumping speed and sorption capacity, have reached certain upper limits. Chemically active metals are the basis of a new generation of NEGs. The introduction of these new materials with high sorption capacity at room temperature is a long-awaited development. These new materials enable the new generation of NEGs to reach faster pumping speeds, significantly higher sticking rates and sorption capacities up to 104 times higher during their lifetimes. Our development efforts focus on producing these chemically active metals with controlled insulation or protection. The main structural forms of our new getter materials are spherical powders, granules and porous multi-layers. The full pumping performance can take place at room temperature with activation temperatures ranging from room temperature to 650 °C. In one of our first pilot projects, our proprietary getter solution was successfully introduced as a getter pump in a double-wall mobile LH2 tank system. Our getters were shown to have very high sorption capacity of all relevant residual gases, including H2. This new concept opens the opportunity for significant vacuum improvements, especially in the field of H2 pumping which is an important task in many different vacuum applications.

  17. Silicon crystal growth in vacuum

    NASA Technical Reports Server (NTRS)

    Khattak, C. P.; Schmid, F.

    1982-01-01

    The most developed process for silicon crystal growth is the Czochralski (CZ) method which was in production for over two decades. In an effort to reduce cost of single crystal silicon for photovoltaic applications, a directional solidification technique, Heat Exchanger Method (HEM), was adapted. Materials used in HEM and CZ furnaces are quite similar (heaters, crucibles, insulation, etc.). To eliminate the cost of high purity argon, it was intended to use vacuum operation in HEM. Two of the major problems encountered in vacuum processing of silicon are crucible decomposition and silicon carbide formation in the melt.

  18. Vacuum Plasma Spraying Replaces Electrodeposition

    NASA Technical Reports Server (NTRS)

    Holmes, Richard R.; Power, Chris; Burns, David H.; Daniel, Ron; Mckechnie, Timothy N.

    1992-01-01

    Vacuum plasma spraying used to fabricate large parts with complicated contours and inner structures, without uninspectable welds. Reduces time, and expense of fabrication. Wall of combustion chamber built up inside of outer nickel-alloy jacket by plasma spraying. Particles of metal sprayed partially melted in plasma gun and thrown at supersonic speed toward deposition surface. Vacuum plasma-spray produces stronger bond between the grooves and covering layer completing channels and wall of combustion chamber. In tests, bond withstood pressure of 20 kpsi, three times allowable limit by old method.

  19. Vacuum Cleaner Fan Being Improved

    NASA Technical Reports Server (NTRS)

    Tweedt, Daniel L.

    1997-01-01

    As part of the technology utilization program at the NASA Lewis Research Center, efforts are underway to transfer aerospace technologies to new areas of practical application. One such effort involves using advanced computational fluid dynamics (CFD) codes for turbomachinery to analyze the internal fluid dynamics of low-speed fans and blowers. This year, the Kirby Company in Cleveland, Ohio, approached NASA with a request for technologies that could help them improve their vacuum cleaners. Of particular interest to Kirby is the high-frequency blade-passing noise generation of their vacuum cleaner fan at low airflow rates.

  20. Method for vacuum fusion bonding

    DOEpatents

    Ackler, Harold D.; Swierkowski, Stefan P.; Tarte, Lisa A.; Hicks, Randall K.

    2001-01-01

    An improved vacuum fusion bonding structure and process for aligned bonding of large area glass plates, patterned with microchannels and access holes and slots, for elevated glass fusion temperatures. Vacuum pumpout of all components is through the bottom platform which yields an untouched, defect free top surface which greatly improves optical access through this smooth surface. Also, a completely non-adherent interlayer, such as graphite, with alignment and location features is located between the main steel platform and the glass plate pair, which makes large improvements in quality, yield, and ease of use, and enables aligned bonding of very large glass structures.

  1. Deep well solar pump

    SciTech Connect

    Vanek, J.

    1990-02-06

    This patent describes, in a pump having a source of gas under pressure, and a gas operated pump, a mechanism periodically injecting gas from the source of gas into the gas operated pump. It comprises: a long period pendulum turning towards a first position by gravity, an injection valve connected between the source of gas under pressure and the gas operated pump, a linkage between the pendulum and the injection valve. The linkage opening the injection valve when the pendulum is in the first position, an impulse tube connected between the injection valve and the gas operated pump, a member having a surface adjacent to the first position of the pendulum, and an elastic impulse bladder connected to the impulse tube adjacent to the surface so that inflation of the impulse bladder on the opening of the injection valve forces the impulse bladder against the pendulum urging the pendulum against the force of gravity toward a second position.

  2. Centrifugal pump fuel system

    SciTech Connect

    McGlone, M.E.; Larkins, L.J.; Johnson, R.O.; Moeller, K.A.

    1993-06-22

    A centrifugal pump fuel system for an engine driven fuel pump for an aircraft gas turbine engine is described comprising: a centrifugal pump having at constant speed rising head/flow characteristic at low flows; a plumbing system receiving flow from the pump, and having at least one control valve located down stream of and defining a discrete volume of the plumbing system; a plumbing resonant frequency defined by the discrete volume, the geometry of the plumbing system, and the bulk modulus of the fuel; a pressure difference regulating valve located adjacent to the discharge of the pump, up stream of the vast majority of the discrete volume; and the frequency response of the regulating valve being significantly less than the frequency response of the plumbing system such that the response of the regulating valve is attenuated at the resonant frequency of the plumbing system.

  3. Rotary Blood Pump

    NASA Technical Reports Server (NTRS)

    Bozeman, Richard J., Jr. (Inventor); Akkerman, James W. (Inventor); Aber, Gregory S. (Inventor); VanDamm, George A. (Inventor); Bacak, James W. (Inventor); Svejkovsky, Paul A. (Inventor); Benkowski, Robert J. (Inventor)

    1996-01-01

    A rotary blood pump includes a pump housing for receiving a flow straightener, a rotor mounted on rotor bearings and having an inducer portion and an impeller portion, and a diffuser. The entrance angle, outlet angle, axial and radial clearances of blades associated with the flow straightener, inducer portion, impeller portion and diffuser are optimized to minimize hemolysis while maintaining pump efficiency. The rotor bearing includes a bearing chamber that is filled with cross-linked blood or other bio-compatible material. A back emf integrated circuit regulates rotor operation and a microcomputer may be used to control one or more back emf integrated circuits. A plurality of magnets are disposed in each of a plurality of impeller blades with a small air gap. A stator may be axially adjusted on the pump housing to absorb bearing load and maximize pump efficiency.

  4. A Valveless Pump

    NASA Astrophysics Data System (ADS)

    Bringley, Thomas; Childress, Stephen; Vandenberghe, Nicolas

    2004-11-01

    We study experimentally a simple valveless mechanical pump. The pumping mechanism could help to explain the successful circulation of blood in the cardiovascular systems of the human fetus, certain organisms whose hearts have no valves, and a person undergoing CPR. Because of its simplicity, the pump may also have applications in microfluidics. The experimental setup consists of two connected sections of tube, one rigid and one elastic, filled with water. To pump, a segment of the elastic section is pressed closed periodically. We examine the effects of varying the location of the forced segment and the forcing frequency. Both the magnitude and the direction of the pumping are observed to depend on both parameters. Moreover, certain frequencies result in destructive interference or resonance. We present some simple numerical models to try to explain these observations.

  5. High pressure liquid gas pump

    NASA Technical Reports Server (NTRS)

    Acres, R. L.

    1972-01-01

    Design and development of two types of pumps for handling liquefied gases are discussed. One pump uses mechanical valve shift and other uses pneumatic valve shift. Illustrations of pumps are provided and detailed description of operation is included.

  6. Refurbishment of a 39 foot thermal vacuum chamber

    NASA Technical Reports Server (NTRS)

    Edwards, Arthur A.

    1994-01-01

    The 39' thermal vacuum chamber at Space Systems/Loral has been used to test numerous spacecraft including those of the GOES, Intelsat, Insat, Superbird, N-Star, NATO and other programs. Ten years ago, the aluminum LN2 shroud experienced serious fatigue failures in the field welded jumper tubing, effectively shutting down the chamber for vacuum testing. The problem was repaired at the time, but new failures began to reappear a few months ago and are now occurring at a rate that suggests that the shroud may again become inoperable. Consequently, Space Systems/Loral is spending in excess of $6 million to replace the shroud and the existing LN2 equipment with a new, state of the art cryogenic system. In May, 1994, a contract was awarded to remove the existing shroud and LN2 pumping system and replace it with a gravity fed shroud and distribution system. Included in the contract are eight skid mounted gaseous nitrogen pumping systems capable of controlling shroud zone temperatures between +150 C and -180 C. The project is scheduled to be completed in April 1995.

  7. Apparatus for Pumping a Fluid

    NASA Technical Reports Server (NTRS)

    Boeyen, Robert Van; Reeh, Jonathan

    2013-01-01

    A fluid pump has been developed for mechanically pumped fluid loops for spacecraft thermal control. Lynntech's technology utilizes a proprietary electrochemically driven pumping mechanism. Conventional rotodynamic and displacement pumps typically do not meet the stringent power and operational reliability requirements of space applications. Lynntech's developmental pump is a highly efficient solid-state pump with essentially no rotating or moving components (apart from metal bellows).

  8. The development of a portable ultrahigh vacuum chamber via silicon block

    NASA Astrophysics Data System (ADS)

    Chuang, Ho-Chiao; Huang, Chia-Shiuan

    2014-05-01

    This paper describes a nonmetallic, light weight portable chamber for ultra-high vacuum (UHV) applications. The chamber consists of a processed silicon block anodically bonding five polished Pyrex glass windows and a Pyrex glass adapter, without using any screws, bolts or vacuum adhesives. The design features provide an alternative chamber for UHV applications which require nonmetallic components. We have cyclically baked the chamber up to 180 °C for 160 h and have achieved an ultimate pressure of 1.4 × 10-9 Torr (limited by our pumping station), with no leak detected. Both Pyrex glass windows and Pyrex glass adapter have been used successfully.

  9. Spent nuclear fuel vacuum drying thermal-hydraulic analysis and dynamic model development status report

    SciTech Connect

    Irwin, J.J.; Ogden, D.M., Westinghouse Hanford

    1996-08-28

    This report summarizes preliminary thermal hydraulic scoping analysis and model development associated with the K Basin spent fuel MCO draining and vacuum drying system. The purpose of the draining and drying system is to remove all free water from the interior of the MCO, baskets, and fuel prior to back filling with inert gas and transfer to the hot conditioning process. Dominant physical processes and parameters are delineated and related quantitatively. Minimum dynamic modeling capability required to simulate the process of transporting heat to the residual water on the fuel and transport of the steam produced from the system by vacuum pumping are defined.

  10. Ultrafast internal conversion dynamics of highly excited pyrrole studied with VUV/UV pump probe spectroscopy

    NASA Astrophysics Data System (ADS)

    Horton, Spencer L.; Liu, Yusong; Chakraborty, Pratip; Matsika, Spiridoula; Weinacht, Thomas

    2017-02-01

    We study the relaxation dynamics of pyrrole after excitation with an 8 eV pump pulse to a state just 0.2 eV below the ionization potential using vacuum ultraviolet/ultraviolet pump probe spectroscopy. Our measurements in conjunction with electronic structure calculations indicate that pyrrole undergoes rapid internal conversion to the ground state in less than 300 fs. We find that internal conversion to the ground state dominates over dissociation.

  11. Solid state radiative heat pump

    DOEpatents

    Berdahl, Paul H.

    1986-01-01

    A solid state radiative heat pump (10, 50, 70) operable at room temperature (300.degree. K.) utilizes a semiconductor having a gap energy in the range of 0.03-0.25 eV and operated reversibly to produce an excess or deficit of charge carriers as compared to thermal equilibrium. In one form of the invention (10, 70) an infrared semiconductor photodiode (21, 71) is used, with forward or reverse bias, to emit an excess or deficit of infrared radiation. In another form of the invention (50), a homogeneous semiconductor (51) is subjected to orthogonal magnetic and electric fields to emit an excess or deficit of infrared radiation. Three methods of enhancing transmission of radiation through the active surface of the semiconductor are disclosed. In one method, an anti-reflection layer (19) is coated into the active surface (13) of the semiconductor (11), the anti-reflection layer (19) having an index of refraction equal to the square root of that of the semiconductor (11). In the second method, a passive layer (75) is spaced from the active surface (73) of the semiconductor (71) by a submicron vacuum gap, the passive layer having an index of refractive equal to that of the semiconductor. In the third method, a coupler (91) with a paraboloid reflecting surface (92) is in contact with the active surface (13, 53) of the semiconductor (11, 51), the coupler having an index of refraction about the same as that of the semiconductor.

  12. Solid state radiative heat pump

    DOEpatents

    Berdahl, P.H.

    1984-09-28

    A solid state radiative heat pump operable at room temperature (300 K) utilizes a semiconductor having a gap energy in the range of 0.03-0.25 eV and operated reversibly to produce an excess or deficit of change carriers as compared equilibrium. In one form of the invention an infrared semiconductor photodiode is used, with forward or reverse bias, to emit an excess or deficit of infrared radiation. In another form of the invention, a homogenous semiconductor is subjected to orthogonal magnetic and electric fields to emit an excess or deficit of infrared radiation. Three methods of enhancing transmission of radiation the active surface of the semiconductor are disclosed. In one method, an anti-refection layer is coated into the active surface of the semiconductor, the anti-reflection layer having an index of refraction equal to the square root of that of the semiconductor. In the second method, a passive layer is speaced trom the active surface of the semiconductor by a submicron vacuum gap, the passive layer having an index of refractive equal to that of the semiconductor. In the third method, a coupler with a paraboloid reflecting surface surface is in contact with the active surface of the semiconductor, the coupler having an index of refraction about the same as that of the semiconductor.

  13. Degassing a vacuum system with in-situ UV radiation

    SciTech Connect

    Koebley, Sean R.; Outlaw, Ronald A.; Dellwo, Randy R.

    2012-11-15

    Photon-stimulated desorption (PSD) from a high-powered ultraviolet source was investigated as a technique to degas a vacuum system. A stainless steel vacuum system was pumped down from atmosphere with different time doses of 185 nm light, and the resulting outgassing rates were compared to that of a control pumpdown without UV assistance. PSD was found to provide a factor of 2 advantage in pumpdown pressure after only 30 min of UV exposure, with no additional advantage observed for longer irradiation times. Specifically, an outgassing rate of 3 Multiplication-Sign 10{sup -10} Torr L s{sup -1} cm{sup -2} was reached 3 h sooner in pumpdowns with UV assistance compared to those without UV, while a rate of 1.2 Multiplication-Sign 10{sup -10} Torr L s{sup -1} cm{sup -2} was reached 16 h sooner in UV runs. The authors calculated that about 22 monolayers of water were desorbed after 30 min of UV exposure. The results indicate that PSD by a 40 W 185 nm UV source can serve as a nonthermal technique to significantly speed the pumpdown of a vacuum system from atmosphere after only 30 min.

  14. Rogue Mode Shileding in NSLS-II Multipole Vacuum Chambers

    SciTech Connect

    Ferreira, M.; Blednykh, A.; Bacha, B.; Borrelli, A.; Hseuh, H.-C.; Kosciuk, B.; Krinsky, S.; Singh, O.; Vetter, K.

    2011-03-28

    Modes with transverse electric field (TE-modes) in the NSLS-II multipole vacuum chamber can be generated at frequencies above 450MHz due to its geometric dimensions. Since the NSLS-II BPM system monitors signals within 10 MHz band at RF frequency of 500 MHz, frequencies of higher-order modes (HOM) can be generated within the transmission band of the band pass filter. In order to avoid systematic errors in the NSLS-II BPM system, we introduced frequency shift of HOMs by using RF metal shielding located in the antechamber slot. We demonstrated numerical modeling and experimental studies of the spurious TE modes in the NSLS-II vacuum chambers with antechamber slot. Calculated frequencies of TE-modes in considered chambers with and without RF shielding were verified experimentally. Flexible BeCu RF shielding inside each chamber at proper location shifts frequencies of H{sub 10p}-modes above {approx}900MHz, except chambers S6 odd and even. These chambers need special attention because of synchrotron radiation from downstream magnets. S6 odd multipole vacuum chamber needs to be measured and the RF shielding length has to be optimized. RF shielding looks adequate for baseline design. Fifty percent of open space provides adequate pumping speed.

  15. Vacuum-jacketed line spacer

    NASA Technical Reports Server (NTRS)

    Houte, F. A.; Mckee, H. B.; Patten, T. C.

    1976-01-01

    Device has three integral, equally spaced leaf springs. Springs separate outer vacuum jacket from fluid carrying line, yet minimize conductive heat leaks and liquid boiloff. One-piece heat spring has sufficient flexibility to accommodate differential thermal expansion of inner and outer line.

  16. Cleaner Vacuum-Bag Curing

    NASA Technical Reports Server (NTRS)

    Clemons, J. M.; Penn, B. G.; Ledbetter, Frank E., III; Daniels, J. G.

    1987-01-01

    Improvement upon recommended procedures saves time and expense. Autoclave molding in vacuum bag cleaner if adhesive-backed covering placed around caul plate as well as on mold plate. Covering easy to remove after curing and leaves caul plate free of resin deposits.

  17. Quantum Vacuum Structure and Cosmology

    SciTech Connect

    Rafelski, Johann; Labun, Lance; Hadad, Yaron; Chen, Pisin; /Taiwan, Natl. Taiwan U. /KIPAC, Menlo Park /SLAC

    2011-12-05

    Contemporary physics faces three great riddles that lie at the intersection of quantum theory, particle physics and cosmology. They are: (1) The expansion of the universe is accelerating - an extra factor of two appears in the size; (2) Zero-point fluctuations do not gravitate - a matter of 120 orders of magnitude; and (3) The 'True' quantum vacuum state does not gravitate. The latter two are explicitly problems related to the interpretation and the physical role and relation of the quantum vacuum with and in general relativity. Their resolution may require a major advance in our formulation and understanding of a common unified approach to quantum physics and gravity. To achieve this goal we must develop an experimental basis and much of the discussion we present is devoted to this task. In the following, we examine the observations and the theory contributing to the current framework comprising these riddles. We consider an interpretation of the first riddle within the context of the universe's quantum vacuum state, and propose an experimental concept to probe the vacuum state of the universe.

  18. Vacuum barrier for excimer lasers

    DOEpatents

    Shurter, Roger P.

    1992-01-01

    A barrier for separating the vacuum area of a diode from the pressurized gas area of an excimer laser. The barrier is a composite material comprising layers of a metal such as copper, along with layers of polyimide, and a matrix of graphite fiber yarns impregnated with epoxy. The barrier is stronger than conventional foil barriers, and allows greater electron throughput.

  19. Vacuum barrier for excimer lasers

    DOEpatents

    Shurter, R.P.

    1992-09-15

    A barrier for separating the vacuum area of a diode from the pressurized gas area of an excimer laser. The barrier is a composite material comprising layers of a metal such as copper, along with layers of polyimide, and a matrix of graphite fiber yarns impregnated with epoxy. The barrier is stronger than conventional foil barriers, and allows greater electron throughput. 3 figs.

  20. Vacuum Flushing of Sewer Solids

    EPA Science Inventory

    The vacuum sewer and tank cleaning (flushing) technology removes sewer solids from urban drainage systems, such as storage tanks and pipes. This technology is both effective and inexpensive. In addition, it can be considered a true green technology. It operates under atmospheri...

  1. Vacuum-insulated catalytic converter

    DOEpatents

    Benson, David K.

    2001-01-01

    A catalytic converter has an inner canister that contains catalyst-coated substrates and an outer canister that encloses an annular, variable vacuum insulation chamber surrounding the inner canister. An annular tank containing phase-change material for heat storage and release is positioned in the variable vacuum insulation chamber a distance spaced part from the inner canister. A reversible hydrogen getter in the variable vacuum insulation chamber, preferably on a surface of the heat storage tank, releases hydrogen into the variable vacuum insulation chamber to conduct heat when the phase-change material is hot and absorbs the hydrogen to limit heat transfer to radiation when the phase-change material is cool. A porous zeolite trap in the inner canister absorbs and retains hydrocarbons from the exhaust gases when the catalyst-coated substrates and zeolite trap are cold and releases the hydrocarbons for reaction on the catalyst-coated substrate when the zeolite trap and catalyst-coated substrate get hot.

  2. Plates for vacuum thermal fusion

    DOEpatents

    Davidson, James C.; Balch, Joseph W.

    2002-01-01

    A process for effectively bonding arbitrary size or shape substrates. The process incorporates vacuum pull down techniques to ensure uniform surface contact during the bonding process. The essence of the process for bonding substrates, such as glass, plastic, or alloys, etc., which have a moderate melting point with a gradual softening point curve, involves the application of an active vacuum source to evacuate interstices between the substrates while at the same time providing a positive force to hold the parts to be bonded in contact. This enables increasing the temperature of the bonding process to ensure that the softening point has been reached and small void areas are filled and come in contact with the opposing substrate. The process is most effective where at least one of the two plates or substrates contain channels or grooves that can be used to apply vacuum between the plates or substrates during the thermal bonding cycle. Also, it is beneficial to provide a vacuum groove or channel near the perimeter of the plates or substrates to ensure bonding of the perimeter of the plates or substrates and reduce the unbonded regions inside the interior region of the plates or substrates.

  3. A vacuum ultraviolet spectrophotometric system

    NASA Technical Reports Server (NTRS)

    Spann, James F.; Keffer, Charles E.; Zukic, Muamer

    1993-01-01

    The development of a vacuum ultraviolet spectrophotometric system for measuring transmittance and reflectance at variable angles is presented. Using various detectors and sources, the spectrophotometric system has been used for wavelengths from 80 nm to 300 nm with optical components up to 80 mm in diameter. The capability exists to make measurements through the visible range.

  4. HIGH PRODUCTIVITY VACUUM BLASTING SYSTEM

    SciTech Connect

    Dr. M.A. Ebadian

    2000-01-13

    The purpose of the project is to increase the productivity and economics of existing vacuum blasting technology. This technology is used to remove radioactive contamination, PCB's and lead-base paint and provides worker and environmental protection by continuously recycling the blast media and the full containment of the dust generated in the process.

  5. Degassing procedure for ultrahigh vacuum

    NASA Technical Reports Server (NTRS)

    Moore, B. C.

    1979-01-01

    Calculations based on diffusion coefficients and degassing rates for stainless-steel vacuum chambers indicate that baking at lower temperatures for longer periods give lower ultimate pressures than rapid baking at high temperatures. Process could reduce pressures in chambers for particle accelerators, fusion reactors, material research, and other applications.

  6. Pressure charged airlift pump

    DOEpatents

    Campbell, Gene K.

    1983-01-01

    A pumping system is described for pumping fluids, such as water with entrained mud and small rocks, out of underground cavities such as drilled wells, which can effectively remove fluids down to a level very close to the bottom of the cavity and which can operate solely by compressed air pumped down through the cavity. The system utilizes a subassembly having a pair of parallel conduit sections (44, 46) adapted to be connected onto the bottom of a drill string utilized for drilling the cavity, the drill string also having a pair of coaxially extending conduits. The subassembly includes an upper portion which has means for connection onto the drill string and terminates the first conduit of the drill string in a plenum (55). A compressed air-driven pump (62) is suspended from the upper portion. The pump sucks fluids from the bottom of the cavity and discharges them into the second conduit. Compressed air pumped down through the first conduit (46) to the plenum powers the compressed air-driven pump and aerates the fluid in the second conduit to lift it to the earth's surface.

  7. Deep well pump

    SciTech Connect

    Downen, J.L.; Sutliff, W.N.

    1981-06-16

    A pump barrel open at its lower end is coupled at its upper end by a tubular adapter assembly to the lower end of a pump tubing string. This assembly presents an internal bevelled sealing latching annulus, an axially bored pump head being radially expansively spring latched in a fixed axial sealed relation with the annulus to seal the upper end of the pump barrel from the adapter assembly to form a pump compression chamber surrounding a hollow polish rod extending upwardly from a plunger mounted on the lower end of the polish rod for reciprocation in the pump barrel. The plunger carries tandem travelling valves close beneath its connection with the polish rod. The lower valve opening to receive oil through the barrel and plunger on the down stroke and concurrently delivering such oil into the compression chamber. The upper valve closes on the down stroke and opening on the up stroke during which the lower valve closes to expel oil trapped in the compression chamber upward through the upper valve into the lower end of the hollow polish rod which oil is discharged at the upper end thereof into the pump tubing string through the fitting adapting the polish rod to the lower end of the sucker rod.

  8. Fuel injection pump

    SciTech Connect

    Iiyama, A.; Nishimura, T.

    1988-12-06

    This patent describes a fuel injection pump comprising: (a) engageable first and second cam members, the first cam member reciprocating axially as the first cam member moves angularly relative to the second cam member when the first and second cam members are in engagement; (b) means for urging the first cam member toward the second cam member to engage the first and second cam members; (c) a plunger connected to the first cam member for reciprocation with the first cam member, the plunger defining at least a part of a pumping chamber, the pumping chamber contracting and expanding as the plunger reciprocates; (d) means for allowing fuel to move into the pumping chamber as the pumping chamber expands in a fuel intake stroke; (e) means for allowing the fuel to move out of the pumping chamber as the pumping chamber contracts in a fuel compression stroke; and (f) means for resisting movement of the plunger in at least part of the fuel compression stroke and relieving resistance to the movement of the plunger in the fuel intake stroke wherein the resisting means comprises a piston slidably mounted on the plunger, a spring urging the piston to seat the piston on a shoulder on the plunger so that the piston reciprocates as the plunger reciprocates, wherein the piston is seated on the shoulder in the fuel compression stroke and separates from the shoulder against the force of the spring in the fuel intake stroke, a second fluid chamber at least partially defined by the piston.

  9. Variable displacement vane pump

    SciTech Connect

    Tschantz, J.S.; Bisson, B.J.

    1997-12-31

    What has been developed under this program is a pumping system which can vary the amount of fuel delivered according to engine needs, thereby reducing the temperature rise of the fuel to very low levels. This permits the elimination of the air/oil coolers and conserves the vital airflow through the fan. The variable displacement vane pump (VDVP) also permits a substantial simplification of the control system with the elimination of complex metering valves, offering a significant reduction in fuel system cost. This program was initiated to develop a technology that embodied the ruggedness of the gear pump with the efficiency and metering versatility of the variable displacement vane pump. Thick metal vanes emulate the teeth on pumping gears while the simple, elegant swing cam feature provides the variable displacement capability without the unwieldy multiple cam segments found in other concepts. The result is a pumping architecture which is rugged, light in weight and extremely versatile, having demonstrated superb heat management and controllability in extensive bench and engine testing. This paper will report the results that the pumps have achieved to date both in terms of durability and efficiency.

  10. Multiphase pumping - operation & control

    SciTech Connect

    Salis, J. de; Marolies, C. de; Falcimaigne, J.

    1996-12-31

    This paper reviews field issues related to the planning, installation and operation of the helico-axial multiphase pumps. Interest for multiphase production, which leads to simpler and smaller in-field installations, is primarily dictated by the need for more a cost effective production system. Multiphase pumping is essentially a means of adding energy to the unprocessed effluent which enables the liquid/gas mixture to be transported over long distances without the need for prior separation. The Poseidon helico-axial pumps, under normal operating conditions, are largely unaffected by process fluctuations at pump inlet (changes in pressure, liquid or gas flow rate). They have demonstrated a stable behavior (self-adaptive capability with regards to instantaneous changes). A multiphase pump set is designed to operate under changing/fluctuating process conditions. An important issue related to pump operability and flexibility has to do with the driver selection: fixed speed vs. variable speed. In some cases a fixed speed drive provides sufficient operational flexibility. In other cases variable speed can be chosen. Pump operation & control strategies are presented and discussed.

  11. Microfluidic reflow pumps.

    PubMed

    Haslam, Bryan; Tsai, Long-Fang; Anderson, Ryan R; Kim, Seunghyun; Hu, Weisheng; Nordin, Gregory P

    2015-07-01

    A new microfluidic pump, termed a reflow pump, is designed to operate with a sub-μl sample volume and transport it back and forth between two pneumatically actuated reservoirs through a flow channel typically containing one or more sensor surfaces. The ultimate motivation is to efficiently use the small sample volume in conjunction with convection to maximize analyte flux to the sensor surface(s) in order to minimize sensor response time. In this paper, we focus on the operational properties of the pumps themselves (rather than the sensor surfaces), and demonstrate both two-layer and three-layer polydimethylsiloxane reflow pumps. For the three-layer pump, we examine the effects of reservoir actuation pressure and actuation period, and demonstrate average volumetric flow rates as high as 500 μl/min. We also show that the two-layer design can pump up to 93% of the sample volume during each half period and demonstrate integration of a reflow pump with a single-chip microcantilever array to measure maximum flow rate.

  12. Vacuum polarization and Hawking radiation

    NASA Astrophysics Data System (ADS)

    Rahmati, Shohreh

    Quantum gravity is one of the interesting fields in contemporary physics which is still in progress. The purpose of quantum gravity is to present a quantum description for spacetime at 10-33cm or find the 'quanta' of gravitational interaction.. At present, the most viable theory to describe gravitational interaction is general relativity which is a classical theory. Semi-classical quantum gravity or quantum field theory in curved spacetime is an approximation to a full quantum theory of gravity. This approximation considers gravity as a classical field and matter fields are quantized. One interesting phenomena in semi-classical quantum gravity is Hawking radiation. Hawking radiation was derived by Stephen Hawking as a thermal emission of particles from the black hole horizon. In this thesis we obtain the spectrum of Hawking radiation using a new method. Vacuum is defined as the possible lowest energy state which is filled with pairs of virtual particle-antiparticle. Vacuum polarization is a consequence of pair creation in the presence of an external field such as an electromagnetic or gravitational field. Vacuum polarization in the vicinity of a black hole horizon can be interpreted as the cause of the emission from black holes known as Hawking radiation. In this thesis we try to obtain the Hawking spectrum using this approach. We re-examine vacuum polarization of a scalar field in a quasi-local volume that includes the horizon. We study the interaction of a scalar field with the background gravitational field of the black hole in the desired quasi-local region. The quasi-local volume is a hollow cylinder enclosed by two membranes, one inside the horizon and one outside the horizon. The net rate of particle emission can be obtained as the difference of the vacuum polarization from the outer boundary and inner boundary of the cylinder. Thus we found a new method to derive Hawking emission which is unitary and well defined in quantum field theory.

  13. Design of Portable Mass Spectrometers with Handheld Probes: Aspects of the Sampling and Miniature Pumping Systems

    PubMed Central

    Chen, Chien-Hsun; Chen, Tsung-Chi; Zhou, Xiaoyu; Kline-Schoder, Robert; Sorensen, Paul; Cooks, R. Graham; Ouyang, Zheng

    2014-01-01

    Miniature mass spectrometry analytical systems of backpack configuration fitted with sampling probes could potentially be of significant interest for in-field, real-time chemical analysis. In this study, various configurations were explored in which a long narrow tube was used to connect the turbo and backing pumps used to create and maintain vacuum. Also, for the first time we introduced two new types of pumps for miniature mass spectrometers, the Creare 130g drag pump and Creare 350g scroll backing pump. These pumps, along with another Creare 550 turbo pump and the commercially available Pfeiffer HiPace 10 turbo and KnF diaphragm backing pumps, were tested with the backpack configurations. The system performance, especially the scan time, was characterized when used with a discontinuous atmospheric pressure interface (DAPI) for ion introduction. The pumping performance in the pressure region above 1 mtorr is critical for DAPI operation. The 550g turbo pump was shown to have a relatively higher pumping speed above 1 mtorr and gave a scan time of 300 ms, almost half the value obtained with the larger, heavier HiPace 10 often used with miniature mass spectrometers. The 350 g scroll pump was also found to be an improvement over the diaphragm pumps generally used as backing pumps. With a coaxial low temperature plasma ion source, direct analysis of low volatility compounds glass slides was demonstrated, including 1 ng DNP (2,4-Dinitrophenol) and 10ng TNT (2,4,6-trinitrotoluene) with Creare 550g turbo pump as well as 10 ng cocaine and 20 ng DNP with Creare 130g drag pump. PMID:25404157

  14. Design of portable mass spectrometers with handheld probes: aspects of the sampling and miniature pumping systems.

    PubMed

    Chen, Chien-Hsun; Chen, Tsung-Chi; Zhou, Xiaoyu; Kline-Schoder, Robert; Sorensen, Paul; Cooks, R Graham; Ouyang, Zheng

    2015-02-01

    Miniature mass spectrometry analytical systems of backpack configuration fitted with sampling probes could potentially be of significant interest for in-field, real-time chemical analysis. In this study, various configurations were explored in which a long narrow tube was used to connect the turbo and backing pumps used to create and maintain vacuum. Also, for the first time we introduced two new types of pumps for miniature mass spectrometers, the Creare 130 g drag pump and Creare 350 g scroll backing pump. These pumps, along with another Creare 550 turbo pump and the commercially available Pfeiffer HiPace 10 turbo and KnF diaphragm backing pumps, were tested with the backpack configurations. The system performance, especially the scan time, was characterized when used with a discontinuous atmospheric pressure interface (DAPI) for ion introduction. The pumping performance in the pressure region above 1 mtorr is critical for DAPI operation. The 550 g turbo pump was shown to have a relatively higher pumping speed above 1 mtorr and gave a scan time of 300 ms, almost half the value obtained with the larger, heavier HiPace 10 often used with miniature mass spectrometers. The 350 g scroll pump was also found to be an improvement over the diaphragm pumps generally used as backing pumps. With a coaxial low temperature plasma ion source, direct analysis of low volatility compounds glass slides was demonstrated, including 1 ng DNP (2,4-Dinitrophenol) and 10 ng TNT (2,4,6-trinitrotoluene) with Creare 550 g turbo pump as well as 10 ng cocaine and 20 ng DNP with Creare 130 g drag pump.

  15. Design of Portable Mass Spectrometers with Handheld Probes: Aspects of the Sampling and Miniature Pumping Systems

    NASA Astrophysics Data System (ADS)

    Chen, Chien-Hsun; Chen, Tsung-Chi; Zhou, Xiaoyu; Kline-Schoder, Robert; Sorensen, Paul; Cooks, R. Graham; Ouyang, Zheng

    2015-02-01

    Miniature mass spectrometry analytical systems of backpack configuration fitted with sampling probes could potentially be of significant interest for in-field, real-time chemical analysis. In this study, various configurations were explored in which a long narrow tube was used to connect the turbo and backing pumps used to create and maintain vacuum. Also, for the first time we introduced two new types of pumps for miniature mass spectrometers, the Creare 130 g drag pump and Creare 350 g scroll backing pump. These pumps, along with another Creare 550 turbo pump and the commercially available Pfeiffer HiPace 10 turbo and KnF diaphragm backing pumps, were tested with the backpack configurations. The system performance, especially the scan time, was characterized when used with a discontinuous atmospheric pressure interface (DAPI) for ion introduction. The pumping performance in the pressure region above 1 mtorr is critical for DAPI operation. The 550 g turbo pump was shown to have a relatively higher pumping speed above 1 mtorr and gave a scan time of 300 ms, almost half the value obtained with the larger, heavier HiPace 10 often used with miniature mass spectrometers. The 350 g scroll pump was also found to be an improvement over the diaphragm pumps generally used as backing pumps. With a coaxial low temperature plasma ion source, direct analysis of low volatility compounds glass slides was demonstrated, including 1 ng DNP (2,4-Dinitrophenol) and 10 ng TNT (2,4,6-trinitrotoluene) with Creare 550 g turbo pump as well as 10 ng cocaine and 20 ng DNP with Creare 130 g drag pump.

  16. Materials for ultra-high vacuum

    SciTech Connect

    Lee, G.

    1989-08-15

    This report discusses materials for use in ultrahigh vacuum systems of 1 {times} 10{sup {minus}9} Torr or lower. The author briefly discusses alloys, solders, insulators and joining methods for vacuum systems. (JDL)

  17. Vacuum casting of thick polymeric films

    NASA Technical Reports Server (NTRS)

    Cuddihy, E. F.; Moacanin, J.

    1979-01-01

    Bubble formation and layering, which often plague vacuum-evaporated films, are prevented by properly regulating process parameters. Vacuum casting may be applicable to forming thick films of other polymer/solvent solutions.

  18. Ceramic-to-metal vacuum seal

    NASA Technical Reports Server (NTRS)

    Sackerlotzky, O. H.

    1979-01-01

    Knife-edge sealing technique forms reliable, vacuum-tight bonds between materials having very different thermal-expansion characteristics. Seal is thin and flexible and absorb shear, hoop, and bonding stresses at joint so that seal remains vacuum tight.

  19. A Review of Maintenance of Vacuum inside Vacuum Insulation Panels

    NASA Astrophysics Data System (ADS)

    Yang, Chun Guang; Xu, Lie

    The growing concerns over global energy crisis and the phasing out of polyurethane foams blown with CFC-11, which has high Ozone Depletion Potential(ODP), have pushed thermal insulation technology to improve its efficiency. Vacuum Insulation Panel(VIP) has been regarded as a super thermal insulation material with a thermal resistance of about 5-10 times higher than conventional thermal insulation. Appropriate vacuum in VIP is one of the most important factors contributing to the long term heat insulation performance of VIP. In this paper, the researches on three factors, which influence internal pressure inside VIP, including gas and water vapor permeation through the barrier, gas absorption by getters and desiccants and outgassing of the kernel, were reviewed respectively. Following this, the research emphasis and suggestions, which should be paid attention to, were summarized.

  20. Optimization of High-Energy Implanter Beamline Pumping

    SciTech Connect

    LaFontaine, Marvin; Pharand, Michel; Huang Yongzhang; Pokidov, Ilya; Ferrara, Joseph

    2006-11-13

    A high-energy implanter process chamber and its pumping configuration were designed to minimize the residual gas density in the endstation. A modified Nastran trade mark sign finite-element analysis (FEA) code was used to calculate the pressure distribution and gas flow within the process chamber. The modified FE method was readily applied to the internal geometry of the scan chamber, the corrector magnet waveguide, and the process chamber, which included the scan arm assembly, 300mm wafer, and plasma electron flood gun (PEF). Using the modified Nastran code, the gas flow and pressure distribution within the beamline geometry were calculated. The gas load consisted of H2, which is generated by photoresist (PR) outgassing from the 300mm wafer, and Xe from the plasma electron flood gun. Several pumping configurations were assessed, with each consisting of various locations and pumping capacities of vacuum pumps. The pressure distribution results for each configuration are presented, along with pumping efficiency results which are helpful in selecting the optimum pump configuration. The analysis results were compared to measured data, indicating a good correlation between the two.

  1. Optimization of High-Energy Implanter Beamline Pumping

    NASA Astrophysics Data System (ADS)

    LaFontaine, Marvin; Pharand, Michel; Huang, Yongzhang; Pokidov, Ilya; Ferrara, Joseph

    2006-11-01

    A high-energy implanter process chamber and its pumping configuration were designed to minimize the residual gas density in the endstation. A modified Nastran™ finite-element analysis (FEA) code was used to calculate the pressure distribution and gas flow within the process chamber. The modified FE method was readily applied to the internal geometry of the scan chamber, the corrector magnet waveguide, and the process chamber, which included the scan arm assembly, 300mm wafer, and plasma electron flood gun (PEF). Using the modified Nastran code, the gas flow and pressure distribution within the beamline geometry were calculated. The gas load consisted of H2, which is generated by photoresist (PR) outgassing from the 300mm wafer, and Xe from the plasma electron flood gun. Several pumping configurations were assessed, with each consisting of various locations and pumping capacities of vacuum pumps. The pressure distribution results for each configuration are presented, along with pumping efficiency results which are helpful in selecting the optimum pump configuration. The analysis results were compared to measured data, indicating a good correlation between the two.

  2. REQUIREMENTS AND GUIDELINES FOR NSLS EXPERIMENTAL BEAM LINE VACUUM SYSTEMS-REVISION B.

    SciTech Connect

    FOERSTER,C.

    1999-05-01

    Typical beam lines are comprised of an assembly of vacuum valves and shutters referred to as a ''front end'', optical elements to monochromatize, focus and split the photon beam, and an experimental area where a target sample is placed into the photon beam and data from the interaction is detected and recorded. Windows are used to separate sections of beam lines that are not compatible with storage ring ultra high vacuum. Some experimental beam lines share a common vacuum with storage rings. Sections of beam lines are only allowed to vent up to atmospheric pressure using pure nitrogen gas after a vacuum barrier is established to protect ring vacuum. The front end may only be bled up when there is no current in the machine. This is especially true on the VUV storage ring where for most experiments, windows are not used. For the shorter wavelength, more energetic photons of the x-ray ring, beryllium windows are used at various beam line locations so that the monochromator, mirror box or sample chamber may be used in a helium atmosphere or rough vacuum. The window separates ring vacuum from the environment of the downstream beam line components. The stored beam lifetime in the storage rings and the maintenance of desirable reflection properties of optical surfaces depend upon hydrocarbon-free, ultra-high vacuum systems. Storage ring vacuum systems will operate at pressures of {approximately} 1 x 10{sup {minus}10} Torr without beam and {approximately} 1 x 10{sup {minus}9} Torr with beam. Systems are free of hydrocarbons in the sense that no pumps, valves, etc. containing organics are used. Components are all-metal, chemically cleaned and bakeable. To the extent that beam lines share a common vacuum with the storage ring, the same criteria will hold for beam line components. The design philosophy for NSLS beam lines is to use all-metal, hydrocarbon-free front end components and recommend that experimenters use this approach for common vacuum hardware downstream of front

  3. Helium processing for deuterium/helium burns in ITER's physics phase

    SciTech Connect

    Finn, P.A.; Sze, D.K.

    1991-01-01

    The requirements for vacuum pumping and fuel processing for deuterium/helium (D/{sup 3}He) burns in the physics operating phase for the International Thermonuclear Experimental Reactor (ITER) were assessed. These burns are expected to have low fusion power (100 MW), short burn times ({le}30 s), limited operation (2000 shots), and a fractional burn {approximately}0.3%. For the physics phase, the fuel processing system will include several units to separate deuterium and helium (activated charcoal bed, SAES getter and a Pd/Ag diffuser), as well as an isotopic separation system to separate {sup 3}He and {sup 4}He. The needed vacuum system's cryosorption surface area may be as large as 10 m{sup 2} if the burn time is {approximately}200 s, the fractional burn is <0.3%, or the fusion power is >100 MW. 8 refs., 1 fig., 4 tabs.

  4. Switching Circuit for Shop Vacuum System

    NASA Technical Reports Server (NTRS)

    Burley, R. K.

    1987-01-01

    No internal connections to machine tools required. Switching circuit controls vacuum system draws debris from grinders and sanders in machine shop. Circuit automatically turns on vacuum system whenever at least one sander or grinder operating. Debris safely removed, even when operator neglects to turn on vacuum system manually. Pickup coils sense alternating magnetic fields just outside operating machines. Signal from any coil or combination of coils causes vacuum system to be turned on.

  5. Absorption heat pump system

    DOEpatents

    Grossman, G.

    1982-06-16

    The efficiency of an absorption heat pump system is improved by conducting liquid from a second stage evaporator thereof to an auxiliary heat exchanger positioned downstream of a primary heat exchanger in the desorber of the system.

  6. Intelligent pumping system developed

    SciTech Connect

    Not Available

    1983-06-01

    The oil field's first intelligent rod pumping system designed specifically to reduce the cost of pumping oil wells now is a reality. As a plus benefit, the system (called Liftronic) is compact and quiet. The new system combines an efficient mechanical design with a computer control system to reduce pumping costs. The unit stands less than 8 ft high, or approx. one-fourth the height of a comparable beam unit. It also mounts directly on the wellhead. The entire system can be concealed behind a fence or enclosed within a small building to make it a more attractive neighbor in residential, commercial, or recreational areas. It is useful also for agricultural areas where overhead irrigation systems restrict the use of many oil field pumping systems.

  7. Keeping Hearts Pumping

    NASA Technical Reports Server (NTRS)

    2002-01-01

    A collaboration between NASA, Dr. Michael DeBakey, Dr. George Noon, and MicroMed Technology, Inc., resulted in a life-saving heart pump for patients awaiting heart transplants. The MicroMed DeBakey VAD functions as a "bridge to heart transplant" by pumping blood throughout the body to keep critically ill patients alive until a donor heart is available. Weighing less than 4 ounces and measuring 1 inch by 3 inches, the pump is approximately one-tenth the size of other currently marketed pulsatile VADs. This makes it less invasive and ideal for smaller adults and children. Because of the pump's small size, less than 5 percent of the patients implanted developed device-related infections. It can operate up to 8 hours on batteries, giving patients the mobility to do normal, everyday activities.The MicroMed DeBakey VAD is a registered trademark of MicroMed Technology, Inc.

  8. Regenerative Hydride Heat Pump

    NASA Technical Reports Server (NTRS)

    Jones, Jack A.

    1992-01-01

    Hydride heat pump features regenerative heating and single circulation loop. Counterflow heat exchangers accommodate different temperatures of FeTi and LaNi4.7Al0.3 subloops. Heating scheme increases efficiency.

  9. Selecting multiphase pumps

    SciTech Connect

    Prang, A.J.

    1997-02-01

    Multiphase pumps in petroleum applications today must handle liquid products containing large amounts of gas, and often including water and sand as well. In the past, gas was commonly separated and flared off at the well head, and only liquid product was piped along for further processing. Using this setup, processing the gas as well as the liquid requires separators, compressors and dual pipelines. Rotary two-screw units are ideal for multiphase use, as they can pump any product that can be introduced into the suction passages of their screws. These devices also effectively handle heat generation from compressed gases. To select units for multiphase applications, an engineer should be familiar with these pumps and how they work. This article discusses rotary-screw pumps and how to effectively select a unit for multiphase service.

  10. Pumping and Breastmilk Storage

    MedlinePlus

    ... by washing your pumping equipment with soap and water and letting the equipment air dry. Storage of breastmilk Store your breastmilk in clean glass or hard BPA-free plastic bottles with tight-fitting lids. You can also use ...

  11. GAS METERING PUMP

    DOEpatents

    George, C.M.

    1957-12-31

    A liquid piston gas pump is described, capable of pumping minute amounts of gas in accurately measurable quantities. The pump consists of a flanged cylindrical regulating chamber and a mercury filled bellows. Sealed to the ABSTRACTS regulating chamber is a value and having a gas inlet and outlet, the inlet being connected by a helical channel to the bellows. A gravity check valve is in the gas outlet, so the gas passes through the inlet and the helical channel to the bellows where the pumping action as well as the metering is accomplished by the actuation of the mercury filled bellows. The gas then flows through the check valve and outlet to any associated apparatus.

  12. Pressurized Vessel Slurry Pumping

    SciTech Connect

    Pound, C.R.

    2001-09-17

    This report summarizes testing of an alternate ''pressurized vessel slurry pumping'' apparatus. The principle is similar to rural domestic water systems and ''acid eggs'' used in chemical laboratories in that material is extruded by displacement with compressed air.

  13. Sliding valve pump

    SciTech Connect

    Rupert, C.L.

    1980-09-09

    A sliding valve pump for oil wells which includes a working barrel having a plurality of apertures located in spaced relationship in the wall thereof and a pair of travelling valves fitted within the working barrel and carried by a plunger rod, the valves also having a plurality of apertures or ports for periodic registration with the ports in the working barrel wall to facilitate pumping of fluid from an oil reservoir or pool to the surface. The pump is designed to pull the oil-gas mixture from the reservoir pool into the lower section of the working barrel on the downward stroke, and to subsequently pump the collected oil through the barrel and tubing upwardly toward the surface on the upward stroke.

  14. Fuel injection pumps

    SciTech Connect

    Howes, P.

    1985-04-02

    A fuel injection pump of the rotary distributor type includes a cam actuated plunger housing in a bore and an adjustable fuel control member which varies the amount of fuel supplied to the bore. The pump also includes a timing piston connected to the cam, the piston being biased by a spring against the action of fuel under pressure. In order to vary the timing under certain conditions a control piston serves as an abutment for the spring and the application of pressure to the control piston is controlled by a valve which has a valve element coupled to a throttle member of the pump the valve having a housing which is secured on the exterior of the pump.

  15. High efficiency centrifugal pump

    SciTech Connect

    Nasvytis, P.J.; Jahrstorfer, G.W.

    1983-10-11

    A high speed fuel pump for a gas turnbine engine has a positively-driven shroud positioned between a main impeller and the wall of a pumping cavity to reduce impeller drag. The shroud is formed by a first disc having a boost impeller connected to its central hub portion and a second disc having a gear carried by its central hub portion. The main drive shaft assembly to which the main impeller is connected, carries a gear which meshes with gear mounted upon a shaft. The shaft also carries a gear which meshes with the gear. The gears are sized so that the shroud is driven at one-half the speed of the main impeller in order to maximize impeller drag reduction and enhance pumping capability when severe inlet conditions are present at the pump inlet.

  16. Absorption heat pump system

    DOEpatents

    Grossman, Gershon

    1984-01-01

    The efficiency of an absorption heat pump system is improved by conducting liquid from a second stage evaporator thereof to an auxiliary heat exchanger positioned downstream of a primary heat exchanger in the desorber of the system.

  17. Direct nuclear pumped laser

    DOEpatents

    Miley, George H.; Wells, William E.; DeYoung, Russell J.

    1978-01-01

    There is provided a direct nuclear pumped gas laser in which the lasing mechanism is collisional radiated recombination of ions. The gas laser active medium is a mixture of the gases, with one example being neon and nitrogen.

  18. Using a Breast Pump

    MedlinePlus

    ... 15 seconds, then rinse with plenty of warm water. After washing, dry your hands thoroughly with a clean paper towel. You do not need to wash your breasts before you pump unless you have been using a cream, ointment, ...

  19. Underground pumped hydroelectric storage

    NASA Astrophysics Data System (ADS)

    Allen, R. D.; Doherty, T. J.; Kannberg, L. D.

    1984-07-01

    Underground pumped hydroelectric energy storage was conceived as a modification of surface pumped storage to eliminate dependence upon fortuitous topography, provide higher hydraulic heads, and reduce environmental concerns. A UPHS plant offers substantial savings in investment cost over coal-fired cycling plants and savings in system production costs over gas turbines. Potential location near load centers lowers transmission costs and line losses. Environmental impact is less than that for a coal-fired cycling plant. The inherent benefits include those of all pumped storage (i.e., rapid load response, emergency capacity, improvement in efficiency as pumps improve, and capacity for voltage regulation). A UPHS plant would be powered by either a coal-fired or nuclear baseload plant. The economic capacity of a UPHS plant would be in the range of 1000 to 3000 MW. This storage level is compatible with the load-velocity requirements of a greater metropolitan area with population of 1 million or more.

  20. Water vacuum suction curettage (WVSC): one year's experience.

    PubMed

    Woods, J R; Herrick, C N; White, R M

    1973-05-01

    At Tripler Army Medical Center in Honolulu abortion patients underwent suction curettage using either an electric pump unit (21, group A) or a simple water vacuum pump (WVSC) (28, group B). In both groups the use of the flexible 6 mm uterine curette and method of curettage were the same. For groups A and B the average blood losses were 40 ml and 39 ml. Average tissue volumes removed were 26 ml and 39 ml (greater yield reflects more patients at gestation of 9-10 weeks). From September 1971 to August 1972 400 patients of gestation of 10 weeks or less were curettaged using WVSC. Most of the operations were performed by first-year residents. Complications requiring readmission were not skewed towards largest gestations but distributed throughout the groups suggesting importance of individual technique in equipment use. The complications included retained products of conception (6), endometritis (2), endometritis with retained products of conception (3), and hermorrhage (1). Advantages of the WVSC unit are 1) quiet sound of running water rather than harsh sound of electric pump, 2) requirement of only a standard waterhead making method available to impoverished areas where electricity may be precious, 3) failsafe, unidirectional suction, 4) easy storage, transport, and assemblage, and 5) lack of need for safety pop-off valve because of intrinsic lag time from close of system to development of maximum suction. With its simplicity, safety, and flexibility WVSC is best suited for outpatients.