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Sample records for bent pipe design

  1. Bent-Pipe Vs On-Board Processing

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. Bent-Pipe Vs On-Board Processing. “Bent-Pipe” refers to satellites. that do not process the transmitted signal but merely relay it from one ground station to another. The On-Board Processing allows. Multi-beam frequency re-use which increases satellite raw capacity; ...

  2. Fundamentals of piping design

    CERN Document Server

    Smith, Peter

    2013-01-01

    Written for the piping engineer and designer in the field, this two-part series helps to fill a void in piping literature,since the Rip Weaver books of the '90s were taken out of print at the advent of the Computer Aid Design(CAD) era. Technology may have changed, however the fundamentals of piping rules still apply in the digitalrepresentation of process piping systems. The Fundamentals of Piping Design is an introduction to the designof piping systems, various processes and the layout of pipe work connecting the major items of equipment forthe new hire, the engineering student and the vetera

  3. Pipe drafting and design

    CERN Document Server

    Parisher, Roy A; Parisher

    2000-01-01

    Pipe designers and drafters provide thousands of piping drawings used in the layout of industrial and other facilities. The layouts must comply with safety codes, government standards, client specifications, budget, and start-up date. Pipe Drafting and Design, Second Edition provides step-by-step instructions to walk pipe designers and drafters and students in Engineering Design Graphics and Engineering Technology through the creation of piping arrangement and isometric drawings using symbols for fittings, flanges, valves, and mechanical equipment. The book is appropriate primarily for pipe

  4. Insulated pipe clamp design

    International Nuclear Information System (INIS)

    Anderson, M.J.; Hyde, L.L.; Wagner, S.E.; Severud, L.K.

    1980-01-01

    Thin wall large diameter piping for breeder reactor plants can be subjected to significant thermal shocks during reactor scrams and other upset events. On the Fast Flux Test Facility, the addition of thick clamps directly on the piping was undesired because the differential metal temperatures between the pipe wall and the clamp could have significantly reduced the pipe thermal fatigue life cycle capabilities. Accordingly, an insulated pipe clamp design concept was developed. 5 refs

  5. Insulated pipe clamp design

    International Nuclear Information System (INIS)

    Anderson, M.J.; Hyde, L.L.; Wagner, S.E.; Severud, L.K.

    1980-01-01

    Thin wall large diameter piping for breeder reactor plants can be subjected to significant thermal shocks during reactor scrams and other upset events. On the Fast Flux Test Facility, the addition of thick clamps directly on the piping was undesired because the differential metal temperatures between the pipe wall and the clamp could have significantly reduced the pipe thermal fatigue life cycle capabilities. Accordingly, an insulated pipe clamp design concept was developed. The design considerations and methods along with the development tests are presented. Special considerations to guard against adverse cracking of the insulation material, to maintain the clamp-pipe stiffness desired during a seismic event, to minimize clamp restraint on the pipe during normal pipe heatup, and to resist clamp rotation or spinning on the pipe are emphasized

  6. Pipe drafting and design

    CERN Document Server

    Parisher, Roy A

    2011-01-01

    Pipe Drafting and Design, Third Edition provides step-by-step instructions to walk pipe designers, drafters, and students through the creation of piping arrangement and isometric drawings. It includes instructions for the proper drawing of symbols for fittings, flanges, valves, and mechanical equipment. More than 350 illustrations and photographs provide examples and visual instructions. A unique feature is the systematic arrangement of drawings that begins with the layout of the structural foundations of a facility and continues through to the development of a 3-D model. Advanced chapters

  7. Flexible heat pipes with integrated bioinspired design

    Directory of Open Access Journals (Sweden)

    Chao Yang

    2015-02-01

    Full Text Available In this work we report the facile fabrication and performance evaluation of flexible heat pipes that have integrated bioinspired wick structures and flexible polyurethane polymer connector design between the copper condenser and evaporator. Inside the heat pipe, a bioinspired superhydrophilic strong-base-oxidized copper mesh with multi-scale micro/nano-structures was used as the wicking material and deionized water was selected as working fluid. Thermal resistances of the fabricated flexible heat pipes charged with different filling ratios were measured under thermal power inputs ranging from 2 W to 12 W while the device was bent at different angles. The fabricated heat pipes with a 30% filling ratio demonstrated a low thermal resistance less than 0.01 K/W. Compared with the vertically oriented straight heat pipes, bending from 30° up to 120° has negligible influence on the heat-transfer performance. Furthermore, repeated heating tests indicated that the fabricated flexible heat pipes have consistent and reliable heat-transfer performance, thus would have important applications for advanced thermal management in three dimensional and flexible electronic devices.

  8. Nuclear piping design, pipe support design and engineering during installation

    International Nuclear Information System (INIS)

    Podczerwinski, C.A.

    1983-01-01

    This paper discusses the computer-aided design of the piping and pipe supports of nuclear power plants. Hardware improvements have been made in the areas of man-machine communication, processing speed, and memory density. Topics considered include evolving design systems, application to current needs, safety-related small-bore piping and support design, as-built drawing review and reconciliation, large-bore pipe support design, snubber population reduction, and operating plant modifications. The improvements in man-machine communication hardware permit the designer to communicate with the computer in terms of pictures of elements of the design. The processing speed and memory density improvements enables the assembly of the design on the machine

  9. Nuclear piping design - An overview

    International Nuclear Information System (INIS)

    Pattabiraman, J.; Neelwarne, A.

    1993-01-01

    Nuclear piping design is a continuously evolving process. Advances in analytical tools and the experience gained from the behaviour of structural systems under normal operating and extreme events like earthquake provide necessary inputs for refinement of design procedures/practices to achieve more economical and safe designs. Although, during last two decades considerable improvements in analytical tools were achieved, an overemphasis on providing conservatism in seismic design resulting in non optimal designs still remains. Present paper discusses aspects such as reliability and maintainability in the context of existing codal requirements of nuclear piping. The uncertainty associated with magnitude of seismic events, their damage potential in combination with other operational piping loads and lack of reliable data during 1970's were contributing factors for building conservatism in the seismic design rules/procedures. However, present status of research and experience on performance of above ground piping systems indicate that the damage potential of seismic event has been considerably overestimated and that overstiff designs have been adopted which have drawbacks in satisfying flexibility criteria for normal operations. The optimal design in the context of nuclear piping, therefore, should imply safe and trouble free operation throughout the life of plant with adequate margins provided for sustaining postulated seismic events. Though conformity with ASME code provides basic protection against piping failure, the issues related with reliability and maintainability, crucial for continued safe operation, can be best addressed through a rational design strategy. Such a design strategy should be based on careful evaluation of various loads related to their damage potential and impact on overall safety margins

  10. Dynamic stability of a curved pipe bent in the arc of a circle on hinge ...

    Indian Academy of Sciences (India)

    Sofia e-mail: dlolov@yahoo.com; lilkova−fhe@uacg.bg. MS received 12 September 2005; revised 29 April 2006. Abstract. Curved pipes conveying fluids are investigated in the paper. Methods of numerical solution of the dynamic stability of a pipe in its plane are developed. An example of a curved pipe is solved by these ...

  11. Seismic design of piping systems

    International Nuclear Information System (INIS)

    Anglaret, G.; Beguin, J.L.

    1986-01-01

    This paper deals with the method used in France for the PWR nuclear plants to derive locations and types of supports of auxiliary and secondary piping systems taking earthquake in account. The successive steps of design are described, then the seismic computation method and its particular conditions of applications for piping are presented. The different types of support (and especially seismic ones) are described and also their conditions of installation. The method used to compare functional tests results and computation results in order to control models is mentioned. Some experiments realised on site or in laboratory, in order to validate models and methods, are presented [fr

  12. Nuclear piping and pipe support design and operability relating to loadings and small bore piping

    International Nuclear Information System (INIS)

    Stout, D.H.; Tubbs, J.M.; Callaway, W.O.; Tang, H.T.; Van Duyne, D.A.

    1994-01-01

    The present nuclear piping system design practices for loadings, multiple support design and small bore piping evaluation are overly conservative. The paper discusses the results developed for realistic definitions of loadings and loading combinations with methodology for combining loads under various conditions for supports and multiple support design. The paper also discusses a simplified method developed for performing deadweight and thermal evaluations of small bore piping systems. Although the simplified method is oriented towards the qualification of piping in older plants, this approach is applicable to plants designed to any edition of the ASME Section III or B31.1 piping codes

  13. Review of nuclear piping seismic design requirements

    International Nuclear Information System (INIS)

    Slagis, G.C.; Moore, S.E.

    1994-01-01

    Modern-day nuclear plant piping systems are designed with a large number of seismic supports and snubbers that may be detrimental to plant reliability. Experimental tests have demonstrated the inherent ruggedness of ductile steel piping for seismic loading. Present methods to predict seismic loads on piping are based on linear-elastic analysis methods with low damping. These methods overpredict the seismic response of ductile steel pipe. Section III of the ASME Boiler and Pressure Vessel Code stresses limits for piping systems that are based on considerations of static loads and hence are overly conservative. Appropriate stress limits for seismic loads on piping should be incorporated into the code to allow more flexible piping designs. The existing requirements and methods for seismic design of piping systems, including inherent conservations, are explained to provide a technical foundation for modifications to those requirements. 30 refs., 5 figs., 3 tabs

  14. OVERVIEW OF INDUSTRIAL PIPING STRUCTURAL DESIGN

    OpenAIRE

    Sagar N. Sakharkar*1, Prathamesh Khake 2, Vasant Kolambakar3

    2018-01-01

    Piping network design system has significant role in industrial sector to minimizing losses through designing effective and simplest network. Piping system is time consuming, complex and expensive effort process for construction and chemical plants. The objective of paper is to explore overview of piping network system design, its requirements. ASME B31.3 design grade has elaborated with application. Concept of flexibility such as flexibility factor, stress intensification factor has discusse...

  15. Hot clamp design for LMFBR piping systems

    International Nuclear Information System (INIS)

    Kobayashi, T.; Tateishi, M.

    1990-01-01

    Thin wall large diameter piping for liquid metal fast breeder reactor plants can be subjected to significant thermal transients during reactor scrams. To reduce local thermal stresses, an insulted cold clamp was designed for the Fast Flux Test Facility and was also applied to some following prototype reactors. However, the cost minimization of LMFBR requires much simpler designs. This paper presents a hot clamp design concept, which uses standard clamp halves directly attached to the pipe surface with an initial gap. Combinations of flexible pipe and rigid clamp achieved a self-control effect on clamp induced pipe stresses due to the initial gap. A 3-D contact and inelastic history analysis were performed to verify the hot clamp concept. Considerations to reduce the initial stress at installation, to mitigate the clamp restraint on the pipe expansion during thermal shocks, and to maintain the pipe-clamp stiffness desired during a seismic event are discussed

  16. Hot clamp design for LMFBR piping systems

    International Nuclear Information System (INIS)

    Kobayashi, T.; Tateishi, M.

    1993-01-01

    Thin-wall, large-diameter piping for liquid metal fast breeder reactor (LMFBR) plants can be subjected to significant thermal transients during reactor scrams. To reduce local thermal stresses, an insulated cold clamp was designed for the fast flux test facility and was also applied to some prototype reactors thereafter. However, the cost minimization of LMFBR requires much simpler designs. This paper presents a hot clamp design concept, which uses standard clamp halves directly attached to the pipe surface leaving an initial gap. Combinations of flexible pipe and rigid clamp achieved a self-control effect on clamp-induced pipe stresses due to the initial gap. A 3-D contact and inelastic history analysis were performed to verify the hot clamp concept. Considerations to reduce the initial stress at installation, to mitigate the clamp restraint on the pipe expansion during thermal shocks, and to maintain the pipe-clamp stiffness desired during a seismic event were discussed

  17. Heat pipes theory, design and applications

    CERN Document Server

    Reay, David; Kew, Peter

    2013-01-01

    Heat Pipes, 6th Edition, takes a highly practical approach to the design and selection of heat pipes, making it an essential guide for practicing engineers and an ideal text for postgraduate students. This new edition has been revised to include new information on the underlying theory of heat pipes and heat transfer, and features fully updated applications, new data sections, and updated chapters on design and electronics cooling. The book is a useful reference for those with experience and an accessible introduction for those approaching the topic for the first time. Contains all informat

  18. 49 CFR 192.121 - Design of plastic pipe.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Design of plastic pipe. 192.121 Section 192.121... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Pipe Design § 192.121 Design of plastic pipe. Subject to the limitations of § 192.123, the design pressure for plastic pipe is determined by either of the...

  19. A study on the concentration of CO by the length and the variation of the bent tube of the exhaust pipe for a household gas boiler

    International Nuclear Information System (INIS)

    Leem, Sa Hwan; Huh, Yong Jeong; Lee, Jong Rark

    2008-01-01

    Energy and environment become increasingly serious after the industrial revolution. The demand for gas as an ecofriendly energy source is also increasing. With the demand, the installation and the use of gas boilers have also increased, so the damage to human life by the waste gas (CO and CO 2 ) continues increasing every year. Hence, the aim of this study was to investigate the concentration of CO (Carbon Monoxide) by the length and the variation of the bent tube of the exhaust pipe by installing a boiler with the same method as a household boiler and to discover the harm to humans. For the effect of the length, the allowable concentration of CO is 50ppm, and the 3m of the once bent tube starts exceeding the allowable concentration of CO after 5 minutes, and the 4m and 5m starts exceeding after 3 minutes. In addition, the 1m of three times bent tube starts exceeding the allowable concentration of CO after 3 minutes

  20. Flexible heat pipes with integrated bioinspired design

    OpenAIRE

    Chao Yang; Chengyi Song; Wen Shang; Peng Tao; Tao Deng

    2015-01-01

    In this work we report the facile fabrication and performance evaluation of flexible heat pipes that have integrated bioinspired wick structures and flexible polyurethane polymer connector design between the copper condenser and evaporator. Inside the heat pipe, a bioinspired superhydrophilic strong-base-oxidized copper mesh with multi-scale micro/nano-structures was used as the wicking material and deionized water was selected as working fluid. Thermal resistances of the fabricated flexible ...

  1. Design and analysis for piping systems

    International Nuclear Information System (INIS)

    Sterkel, H.-P.; Cutrim, J.H.C.

    1981-01-01

    The procedure and the typical techniques that are used in NUCLEN for the design and the calculation of the piping of Nuclear Plants. The classification system are generically described and the analysis techniques which are used for the design and verification of the piping systems, i.e. pressure design for the dimensioning of the wallthicknesses, temperature and dead weight analysis together with determination of support points, are shown. The techniques of dynamic design and analyses are described for earthquake and pressure impulse loadings. (Author) [pt

  2. 46 CFR 153.280 - Piping system design.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Piping system design. 153.280 Section 153.280 Shipping... BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Design and Equipment Piping Systems and Cargo Handling Equipment § 153.280 Piping system design. (a) Each cargo piping system must meet...

  3. Observations on seismic design of piping systems

    International Nuclear Information System (INIS)

    Habip, L.M.; Schrammel, D.

    1992-01-01

    Practical aspects of piping system design for seismic loads are considered. Main topics are structural effects of natural earth-quakes, full-scale dynamic tests - with emphasis on work performed at the HDR plant - and implications for the design and qualification of industrial systems and equipment. Experimental evidence and past experience indicate that design-by-rule or qualification-by-inspection can be used at this time to achieve dependable seismic performance, pending the development of piping failure criteria for cyclic overloads of short duration. (orig.)

  4. Design analysis of liquid metal pipe supports

    International Nuclear Information System (INIS)

    Margolin, L.L.; LaSalle, F.R.

    1979-02-01

    Design guidelines pertinent to liquid metal pipe supports are presented. The numerous complex conditions affecting the support stiffness and strength are addressed in detail. Topics covered include modeling of supports for natural frequency and stiffness calculations, support hardware components, formulas for deflection due to torsion, plate bending, and out-of-plane flexibility. A sample analysis and a discussion on stress analysis of supports are included. Also presented are recommendations for design improvements for increasing the stiffness of pipe supports and which were utilized in the FFTF system

  5. Pipe clamp effects on thin-walled pipe design

    International Nuclear Information System (INIS)

    Lindquist, M.R.

    1980-01-01

    Clamp induced stresses in FFTF piping are sufficiently large to require structural assessment. The basic principles and procedures used in analyzing FFTF piping at clamp support locations for compliance with ASME Code rules are given. Typical results from a three-dimensional shell finite element pipe model with clamp loads applied over the clamp/pipe contact area are shown. Analyses performed to categorize clamp induced piping loads as primary or secondary in nature are described. The ELCLAMP Computer Code, which performs analyses at clamp locations combining clamp induced stresses with stresses from overall piping system loads, is discussed. Grouping and enveloping methods to reduce the number of individual clamp locations requiring analysis are described

  6. UOE Pipe Manufacturing Process Simulation: Equipment Designing and Construction

    Science.gov (United States)

    Delistoian, Dmitri; Chirchor, Mihael

    2017-12-01

    UOE pipe manufacturing process influence directly on pipeline resilience and operation capacity. At present most spreaded pipe manufacturing method is UOE. This method is based on cold forming. After each technological step appears a certain stress and strain level. For pipe stress strain study is designed and constructed special equipment that simulate entire technological process.UOE pipe equipment is dedicated for manufacturing of longitudinally submerged arc welded DN 400 (16 inch) steel pipe.

  7. Design and performance optimization of miniature heat pipes in LTCC

    Energy Technology Data Exchange (ETDEWEB)

    Shi, Peter Z; Chua, K M; Wong, Stephen C K; Tan, Y M [Singapore Institute of Manufacturing Technology 71 Nanyang Drive, Singapore 638075 (Singapore)

    2006-04-01

    In this paper, performance evaluation of miniature heat pipes in LTCC was made by numerical analysis, and the optimum miniature heat pipe design was defined. The effect of the groove depth, width and vapor space on the heat transfer capacity of miniature heat pipes was analyzed. Prototypes of the miniature heat pipes in LTCC were fabricated. Preliminary charging, sealing and thermal measurement of the miniature heat pipes were performed, and the challenges were discussed.

  8. Design criteria for piping and nozzles program

    International Nuclear Information System (INIS)

    Moore, S.E.; Bryson, J.W.

    1977-01-01

    This report reviews the activities and accomplishments of the Design Criteria for Piping and Nozzles program being conducted by the Oak Ridge National Laboratory for the period July 1, 1975, to September 30, 1976. The objectives of the program are to conduct integrated experimental and analytical stress analysis studies of piping system components and isolated and closely-spaced pressure vessel nozzles in order to confirm and/or improve the adequacy of structural design criteria and analytical methods used to assure the safe design of nuclear power plants. Activities this year included the development of a finite-element program for analyzing two closely spaced nozzles in a cylindrical pressure vessel; a limited-parameter study of vessels with isolated nozzles, finite-element studies of piping elbows, a fatigue test of an out-of-round elbow, summary and evaluation of experimental studies on the elastic-response and fatigue failure of tees, parameter studies on the behavior of flanged joints, publication of fifteen topical reports and papers on various experimental and analytical studies; and the development and acceptance of a number of design rules changes to the ASME Code. 2 figures, 2 tables

  9. Heat pipes. Design and industrial applications

    International Nuclear Information System (INIS)

    Semeria, R.

    1974-01-01

    Heat pipes are thermosiphons with vaporization where we can distinguish a boiler, a condenser, and eventually an adiabatic zone. To insure the returning liquid flow from the condenser to the boiler, surface tension forces, associated with the gravity forces, if need be, are used. For this, the condensing liquid is sucked by a capillary structure, generally situated against the inner wall. The review of the design methods, and particularly the prediction of the maximal performances shows the advantages and limitations of such devices. The main difficulties are technological for the heat pipes with high temperature liquid metals. The thermohydrodynamical limitations are: the maximum power which can be calculated by a balance between the friction forces and the active ones, the maximum heat flux leading to the dry-out of the evaporator, the critical conditions for the start up associated with the sonic conditions in the vapour phase. The description of heat pipes designed for some industrial applications (mainly for space) is given [fr

  10. Subprogram Calculating The Distance Between Pipe And Plane For Automatic Piping System Design

    International Nuclear Information System (INIS)

    Satmoko, Ari

    2001-01-01

    DISTLNPL subprogram was created using Auto LISP software. This subprogram is planned to complete CAPD (Computer Aided Piping Design) software being developed. The CAPD works under the following method: suggesting piping system line and evaluating whether any obstacle allows the proposed line to be constructed. DISTLNPL is able to compute the distance between pipe and any equipment having plane dimension such as wall, platform, floors, and so on. The pipe is modeled by using a line representing its axis, and the equipment is modeled using a plane limited by some lines. The obtained distance between line and plane gives information whether the pipe crosses the equipment. In the case of crashing, the subprogram will suggest an alternative point to be passed by piping system. So far, DISTLNPL has not been able to be accessed by CAPD yet. However, this subprogram promises good prospect in modeling wall, platform, and floors

  11. Precast, Prestressed Concrete Bent Caps : Volume 1, Preliminary Design Considerations and Experimental Test Program

    Science.gov (United States)

    2018-04-01

    Precast prestressed concrete bent caps may provide significant benefits by enabling accelerated construction of bridge substructures and improve longevity by reducing the propensity for cracking. The Texas Department of Transportation enables the use...

  12. Pipe rupture and steam/water hammer design loads for dynamic analysis of piping systems

    International Nuclear Information System (INIS)

    Strong, B.R. Jr.; Baschiere, R.J.

    1978-01-01

    The design of restraints and protection devices for nuclear Class I and Class II piping systems must consider severe pipe rupture and steam/water hammer loadings. Limited stress margins require that an accurate prediction of these loads be obtained with a minimum of conservatism in the loads. Methods are available currently for such fluid transient load development, but each method is severely restricted as to the complexity and/or the range of fluid state excursions which can be simulated. This paper presents a general technique for generation of pipe rupture and steam/water hammer design loads for dynamic analysis of nuclear piping systems which does not have the limitations of existing methods. Blowdown thrust loadings and unbalanced piping acceleration loads for restraint design of all nuclear piping systems may be found using this method. The technique allows the effects of two-phase distributed friction, liquid flashing and condensation, and the surrounding thermal and mechanical equipment to be modeled. A new form of the fluid momentum equation is presented which incorporates computer generated fluid acceleration histories by inclusion of a geometry integral termed the 'force equivalent area' (FEA). The FEA values permit the coupling of versatile thermal-hydraulic programs to piping dynamics programs. Typical applications of the method to pipe rupture problems are presented and the resultant load histories compared with existing techniques. (Auth.)

  13. Design of a cavity heat pipe receiver experiment

    Science.gov (United States)

    Schneider, Michael G.; Brege, Mark H.; Greenlee, William J.

    1992-01-01

    A cavity heat pipe experiment has been designed to test the critical issues involved with incorporating thermal energy storage canisters into a heat pipe. The experiment is a replication of the operation of a heat receiver for a Brayton solar dynamic power cycle. The heat receiver is composed of a cylindrical receptor surface and an annular heat pipe with thermal energy storage canisters and gaseous working fluid heat exchanger tubes surrounding it. Hardware for the cavity heat pipe experiment will consist of a sector of the heat pipe, complete with gas tube and thermal energy storage canisters. Thermal cycling tests will be performed on the heat pipe sector to simulate the normal energy charge/discharge cycle of the receiver in a spacecraft application.

  14. 49 CFR 192.105 - Design formula for steel pipe.

    Science.gov (United States)

    2010-10-01

    ... for steel pipe. (a) The design pressure for steel pipe is determined in accordance with the following formula: P=(2 St/D)×F×E×T P=Design pressure in pounds per square inch (kPa) gauge. S=Yield strength in... external loads in accordance with § 192.103 may not be included in computing design pressure. F=Design...

  15. Significance of high level test data in piping design

    International Nuclear Information System (INIS)

    McLean, J.L.; Bitner, J.L.

    1991-01-01

    During the 1980's the piping technical community in the U.S. initiated a series of research activities aimed at reducing the conservatism inherent in nuclear piping design. One of these activities was directed at the application of the ASME Code rules to the design of piping subjected to dynamic loads. This paper surveys the test data obtained from three groups in the U.S. and none in the U.K., and correlates the findings as they relate to the failure modes of piping subjected to seismic loads. The failure modes experienced as the result of testing at dynamic loads significantly in excess of anticipated loads specified for any of the ASME Code service levels are discussed. A recommendation is presented for modifying the Code piping rules to reduce the conservatism inherent in seismic design

  16. Optimum design for pipe-support allocation against seismic loading

    International Nuclear Information System (INIS)

    Hara, Fumio; Iwasaki, Akira

    1996-01-01

    This paper deals with the optimum design methodology of a piping system subjected to a seismic design loading to reduce its dynamic response by selecting the location of pipe supports and whereby reducing the number of pipe supports to be used. The author employs the Genetic Algorithm for obtaining a reasonably optimum solution of the pipe support location, support capacity and number of supports. The design condition specified by the support location, support capacity and the number of supports to be used is encored by an integer number string for each of the support allocation candidates and they prepare many strings for expressing various kinds of pipe-support allocation state. Corresponding to each string, the authors evaluate the seismic response of the piping system to the design seismic excitation and apply the Genetic Algorithm to select the next generation candidates of support allocation to improve the seismic design performance specified by a weighted linear combination of seismic response magnitude, support capacity and the number of supports needed. Continuing this selection process, they find a reasonably optimum solution to the seismic design problem. They examine the feasibility of this optimum design method by investigating the optimum solution for 5, 7 and 10 degree-of-freedom models of piping system, and find that this method can offer one a theoretically feasible solution to the problem. They will be, thus, liberated from the severe uncertainty of damping value when the pipe support guaranties the design capacity of damping. Finally, they discuss the usefulness of the Genetic Algorithm for the seismic design problem of piping systems and some sensitive points when it will be applied to actual design problems

  17. 3-Hydroxycinnamic acid - a new central core for the design of bent-shaped liquid crystals

    Czech Academy of Sciences Publication Activity Database

    Kohout, M.; Tůma, J.; Svoboda, J.; Novotná, Vladimíra; Gorecka, E.; Pociecha, D.

    2013-01-01

    Roč. 1, č. 32 (2013), s. 4962-4969 ISSN 2050-7526 R&D Projects: GA ČR GA13-14133S; GA ČR(CZ) GAP204/11/0723 Institutional support: RVO:68378271 Keywords : liquid crystals * bent-shaped mesogen * cinnamic acid Subject RIV: JJ - Other Materials

  18. Design of supporting devices for thin pipes of large diameter

    International Nuclear Information System (INIS)

    Marsault, J.J.; Dornez, R.

    1981-01-01

    When an analysis is made in accordance with ASME Code Class 1 for piping by the stress indices method (NB 3650), the stresses induced locally in the piping by the supports are not taken into account. For piping whose thickness is small in relation to its diameter, which is subject to sudden temperature changes, to seismic shocks and which also operates at high temperature, it is no longer possible to ignore these effects. This is the case with piping of the sodium circuits of fast breeder reactors for which, after performance of mechanical analyses by the Zick method and thermo-mechanical analyses on the support collars of the classic type, with all the uncertainties involved in reckoning the real forces of contact, a design was finally decided upon which corresponds to the double imperative of permitting free radial expansion of the piping while withstanding considerable loads with a minimum of local deformations in the piping. The device adopted consists of a rigid collar connected to the piping by blades which are flexible radially in relation to the pipe and rigid tangentially. These blades are attached to very short ring lugs welded on to the piping. (orig./GL)

  19. Application of sensitivity analysis for optimized piping support design

    International Nuclear Information System (INIS)

    Tai, K.; Nakatogawa, T.; Hisada, T.; Noguchi, H.; Ichihashi, I.; Ogo, H.

    1993-01-01

    The objective of this study was to see if recent developments in non-linear sensitivity analysis could be applied to the design of nuclear piping systems which use non-linear supports and to develop a practical method of designing such piping systems. In the study presented in this paper, the seismic response of a typical piping system was analyzed using a dynamic non-linear FEM and a sensitivity analysis was carried out. Then optimization for the design of the piping system supports was investigated, selecting the support location and yield load of the non-linear supports (bi-linear model) as main design parameters. It was concluded that the optimized design was a matter of combining overall system reliability with the achievement of an efficient damping effect from the non-linear supports. The analysis also demonstrated sensitivity factors are useful in the planning stage of support design. (author)

  20. Small pipe characterization system (SPCS) conceptual design

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, M.O.; Ferrante, T.A.; McKay, M.D.

    1995-01-01

    Throughout the Department of Energy (DOE) complex there are many facilities that have been identified for Decontamination and Decommissioning (D&D). As processes are terminated or brought off-line, facilities are placed on the inactive list, and facility managers and site contractors are required to assure a safe and reliable decommissioning and transition of these facilities to a clean final state. Decommissioning of facilities requires extensive reliable characterization, decontamination and in some cases dismantlement. Characterization of piping systems throughout the DOE complex is becoming more and more necessary. In addition to decommissioning activities, characterization activities are performed as part of surveillance and maintenance (S&M). Because of the extent of contamination, all inactive facilities require some type of S&M. These S&M activities include visual assessment, equipment and material accounting, and maintenance. The majority of the inactive facilities have piping systems 3 inches or smaller that are inaccessible because they are contaminated, imbedded in concrete, or run through hot cells. Many of these piping systems have been inactive for a number of years and there exists no current system condition information or the historical records are poor and/or missing altogether. Many of these piping systems are placed on the contaminated list, not because of known contamination, but because of the risk of internal contamination. Many of the piping systems placed on the contamination list may not have internal contamination. Because there is a potential however, they are treated as such. The cost of D&D can be greatly reduced by identifying and removing hot spot contamination, leaving clean piping to be removed using conventional methods. Accurate characterization of these piping systems is essential before, during and after all D&D activities.

  1. Small pipe characterization system (SPCS) conceptual design

    International Nuclear Information System (INIS)

    Anderson, M.O.; Ferrante, T.A.; McKay, M.D.

    1995-01-01

    Throughout the Department of Energy (DOE) complex there are many facilities that have been identified for Decontamination and Decommissioning (D ampersand D). As processes are terminated or brought off-line, facilities are placed on the inactive list, and facility managers and site contractors are required to assure a safe and reliable decommissioning and transition of these facilities to a clean final state. Decommissioning of facilities requires extensive reliable characterization, decontamination and in some cases dismantlement. Characterization of piping systems throughout the DOE complex is becoming more and more necessary. In addition to decommissioning activities, characterization activities are performed as part of surveillance and maintenance (S ampersand M). Because of the extent of contamination, all inactive facilities require some type of S ampersand M. These S ampersand M activities include visual assessment, equipment and material accounting, and maintenance. The majority of the inactive facilities have piping systems 3 inches or smaller that are inaccessible because they are contaminated, imbedded in concrete, or run through hot cells. Many of these piping systems have been inactive for a number of years and there exists no current system condition information or the historical records are poor and/or missing altogether. Many of these piping systems are placed on the contaminated list, not because of known contamination, but because of the risk of internal contamination. Many of the piping systems placed on the contamination list may not have internal contamination. Because there is a potential however, they are treated as such. The cost of D ampersand D can be greatly reduced by identifying and removing hot spot contamination, leaving clean piping to be removed using conventional methods. Accurate characterization of these piping systems is essential before, during and after all D ampersand D activities

  2. Design and cooling of BESIII beryllium beam pipe

    Science.gov (United States)

    Li, Xunfeng; Ji, Quan; Wang, Li; Zheng, Lifang

    2008-01-01

    The beryllium beam pipe was restructured according to the requirements of the upgraded BESIII (Beijing Spectrometer) experiment. SMO-1 (sparking machining oil no. 1) was selected as the coolant for the central beryllium beam pipe. The cooling gap width of the beryllium beam pipe was calculated, the influence of concentrated heat load on the wall temperature of the beryllium beam pipe was studied, and the optimal velocity of the SMO-1 in the gap was determined at the maximum heat load. A cooling system for the beam pipe was developed to control the outer wall temperature of the beam pipe. The cooling system is reported in this paper with regard to the following two aspects: the layouts and the automation. The performance of the cooling system was tested on the beam pipe model with trim size. The test results show that the design of the beryllium beam pipe is reasonable and that the cooling system achieves the BESIII experimental aim. The cooling system has already passed the acceptance test and has been installed in position. It will be put into practice for the BESIII experiment in 2008.

  3. 225-B ion exchange piping design documentation

    International Nuclear Information System (INIS)

    Prather, M.C.

    1996-02-01

    This document describes the interface between the planned permanent ion exchange piping system and the planned portable ion exchange system. This is part of the Waste Encapsulation and Storage Facility (WESF). In order to decouple this WESF from B-Plant and to improve recovery from a capsule leak, contaminated pool cell water will be recirculated through a portable ion exchange resin system

  4. Procedure for seismic evaluation and design of small bore piping

    International Nuclear Information System (INIS)

    Bilanin, W.; Sills, S.

    1991-01-01

    Simplified methods for the seismic design of small bore piping in nuclear power plants have teen used for many years. Various number of designers have developed unique methods to treat the large number of class 2 and 3 small bore piping systems. This practice has led to a proliferation of methods which are not standardized in the industry. These methods are generally based on enveloping the results of rigorous dynamic or conservative static analysis and result in an excessive number of supports and unrealistically high support loadings. Experience and test data have become available which warranted taking another look at the present methods for analysis of small bore piping. A recently completed Electric Power Research Institute and NCIG (a utility group) activity developed a new procedure for the seismic design and evaluation of small bore piping which provides significant safety and cost benefits. The procedure streamlines the approach to inertial stresses, which is the main feature that achieves the new benefits. Criteria in the procedure for seismic anchor movement and support design are based analysis and focus the designer on credible failure mechanisms. A walkdown of the as-constructed piping system to identify and eliminate undesirable piping features such as adverse spatial interaction is required

  5. Mechatronics Design of an Autonomous Pipe-Inspection Robot

    Directory of Open Access Journals (Sweden)

    Abdellatif Mohamed

    2018-01-01

    Full Text Available Pipelines require periodical inspection to detect corrosion, deformation and congestion with obstacles in the network. Autonomous mobile robots are good solutions for this task. Visual information from the pipe interior associated with a location stamp is needed for inspection. In this paper, the previous designs of autonomous robots are reviewed and a new robot is developed to ensure simple design and smooth motion. Images are processed online to detect irregularity in pipe and then start capturing high resolution pictures to conserve the limited memory size. The new robot moves in pipes and provides video stream of pipe interior with location stamp. The visual information can later be processed offline to extract more information of pipeline condition to make maintenance decisions.

  6. Design guideline to prevent the pipe rupture by radiolysis gases in BWR steam piping

    International Nuclear Information System (INIS)

    Inagaki, T.; Miyagawa, M.; Ota, T.; Sato, T.; Sakata, K.

    2009-01-01

    In late 2001, pipe rupture accidents due to fast combustion of radiolysis gas occurred in Japan and elsewhere's BWR power plants. TENPES began to set up the guideline as action to such a new problem to prevent accumulation and combustion of radiolysis gas in BWR steam piping. And then, the first edition of guideline was published in October 2005. Afterwards, the experimental study about combustion/detonation of radiolysis gas have been continued. And in March 2007, TENPES published a revised edition of the guideline. This is the report of the revised edition of that guideline. According to this guideline, it became possible to design BWR's steam piping to prevent accumulation of radiolysis gas. (author)

  7. Piping and pipeline calculations manual construction, design fabrication and examination

    CERN Document Server

    Ellenberger, Philip

    2010-01-01

    The lack of commentary, or historical perspective, regarding the codes and standards requirements for piping design and construction is an obstacle to the designer, manufacturer, fabricator, supplier, erector, examiner, inspector, and owner who want to provide a safe and economical piping system. An intensive manual, this book will utilize hundreds of calculation and examples based on of 40 years of personal experiences of the author as both an engineer and instructor. Each example demonstrates how the code and standard has been correctly and incorrectly applied. This book is a ?no non

  8. Seismic Design of ITER Component Cooling Water System-1 Piping

    Science.gov (United States)

    Singh, Aditya P.; Jadhav, Mahesh; Sharma, Lalit K.; Gupta, Dinesh K.; Patel, Nirav; Ranjan, Rakesh; Gohil, Guman; Patel, Hiren; Dangi, Jinendra; Kumar, Mohit; Kumar, A. G. A.

    2017-04-01

    The successful performance of ITER machine very much depends upon the effective removal of heat from the in-vessel components and other auxiliary systems during Tokamak operation. This objective will be accomplished by the design of an effective Cooling Water System (CWS). The optimized piping layout design is an important element in CWS design and is one of the major design challenges owing to the factors of large thermal expansion and seismic accelerations; considering safety, accessibility and maintainability aspects. An important sub-system of ITER CWS, Component Cooling Water System-1 (CCWS-1) has very large diameter of pipes up to DN1600 with many intersections to fulfill the process flow requirements of clients for heat removal. Pipe intersection is the weakest link in the layout due to high stress intensification factor. CCWS-1 piping up to secondary confinement isolation valves as well as in-between these isolation valves need to survive a Seismic Level-2 (SL-2) earthquake during the Tokamak operation period to ensure structural stability of the system in the Safe Shutdown Earthquake (SSE) event. This paper presents the design, qualification and optimization of layout of ITER CCWS-1 loop to withstand SSE event combined with sustained and thermal loads as per the load combinations defined by ITER and allowable limits as per ASME B31.3, This paper also highlights the Modal and Response Spectrum Analyses done to find out the natural frequency and system behavior during the seismic event.

  9. Evaluation of aluminum drill-pipe material and design

    Energy Technology Data Exchange (ETDEWEB)

    Placido, Joao C. [PETROBRAS, Rio de Janeiro, RJ (Brazil); Lourenco, Marcelo I.; Netto, Theodoro Antoun [Universidade Federal do Rio de Janeiro (UFRJ), RJ (Brazil). Coordenacao dos Programas de Pos-graduacao de Engenharia (COPPE)

    2008-07-01

    Experimental program and numerical analyses were carried out to investigate the fatigue mechanisms of aluminum drill pipes designed and manufactured in compliance with ISO 15546. The main objective is to improve the fatigue performance of these components by selecting the appropriate aluminum alloy and by enhancing the mechanical design of the threaded steel connector. This paper presents the experimental test program and numerical analyses conducted on a drill-pipe of different materials (Al-Cu-Mg and Al-Zn-Mg system aluminum alloys) and geometry. Material mechanical properties, including S-N curve, were determined through small-scale tests on specimens cut from actual drill pipes. Full-scale experiments were also performed in laboratory. A finite element model of the drill pipe, including the tool-joint region, was developed. The model simulates, through different load steps, the tool-joint hot assembly, and then reproduces the physical experiments numerically in order to obtain the actual stress distribution. Good correlation between full-scale and small-scale fatigue tests was obtained by adjusting the strain/stress levels monitored in the full-scale tests in light of the numerical simulations and performing fatigue life calculations via multiaxial fatigue models. The weak points of the current practice design are highlighted for further development. (author)

  10. Design of megawatt power level heat pipe reactors

    Energy Technology Data Exchange (ETDEWEB)

    Mcclure, Patrick Ray [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Poston, David Irvin [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Dasari, Venkateswara Rao [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Reid, Robert Stowers [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-11-12

    An important niche for nuclear energy is the need for power at remote locations removed from a reliable electrical grid. Nuclear energy has potential applications at strategic defense locations, theaters of battle, remote communities, and emergency locations. With proper safeguards, a 1 to 10-MWe (megawatt electric) mobile reactor system could provide robust, self-contained, and long-term power in any environment. Heat pipe-cooled fast-spectrum nuclear reactors have been identified as a candidate for these applications. Heat pipe reactors, using alkali metal heat pipes, are perfectly suited for mobile applications because their nature is inherently simpler, smaller, and more reliable than “traditional” reactors. The goal of this project was to develop a scalable conceptual design for a compact reactor and to identify scaling issues for compact heat pipe cooled reactors in general. Toward this goal two detailed concepts were developed, the first concept with more conventional materials and a power of about 2 MWe and a the second concept with less conventional materials and a power level of about 5 MWe. A series of more qualitative advanced designs were developed (with less detail) that show power levels can be pushed to approximately 30 MWe.

  11. Design and testing of CRBRP insulated horizontal and vertical pipe clamps

    International Nuclear Information System (INIS)

    Pollono, L.P.; Mello, R.M.

    1980-01-01

    The Clinch River Breeder Reactor Plant (CRBRP) Primary Heat Transport system piping may be characterized as large-diameter, thin-wall piping which transports liquid sodium at high temperatures. The piping is arranged in accord with the elevated loop concept, consisting of large horizontal inplane, expansion loops and long, vertical runs of piping. These characteristics and the postulated thermal transient and seismic loads, which are imposed on the piping, dictate pipe clamp designs that are substantially different from standard off the shelf pipe clamp designs. The design features of the CRBRP horizontal and vertical pipe clamps for the large sodium piping, the various test programs used to verify the clamp designs, and the results of this testing are presented

  12. A precast concrete bridge bent designed to re-center after an earthquake : research report, October 2008.

    Science.gov (United States)

    2008-10-01

    In this study the post-earthquake residual displacements of reinforced concrete bridge bents were investigated. The system had mild steel that was intended to dissipate energy and an unbonded, post-tensioned tendon that was supposed to remain elastic...

  13. A precast concrete bridge bent designed to re-center after an earthquake : draft research report, August 2008.

    Science.gov (United States)

    2008-08-01

    In this study the post-earthquake residual displacements of reinforced concrete bridge bents were investigated. The system had mild steel that was intended to dissipate energy and an unbonded, post-tensioned tendon that was supposed to remain elastic...

  14. Establishing a design procedure for buried steel-reinforced high-density polyethylene pipes : a field study, [technical summary].

    Science.gov (United States)

    2015-11-01

    Several national standards and specification have been developed for design, installation, : and materials for precast concrete pipe, corrugated metal pipe, and HDPE pipes. However, : no national accepted installation standard or design method is ava...

  15. Sensitivity study of the monogroove with screen heat pipe design

    Science.gov (United States)

    Evans, Austin L.; Joyce, Martin

    1988-01-01

    The present sensitivity study of design variable effects on the performance of a monogroove-with-screen heat pipe obtains performance curves for maximum heat-transfer rates vs. operating temperatures by means of a computer code; performance projections for both 1-g and zero-g conditions are obtainable. The variables in question were liquid and vapor channel design, wall groove design, and the number of feed lines in the evaporator and condenser. The effect on performance of three different working fluids, namely ammonia, methanol, and water, were also determined. Greatest sensitivity was to changes in liquid and vapor channel diameters.

  16. Fatigue design of nuclear class 1 piping considering thermal stratification

    International Nuclear Information System (INIS)

    Kweon, Hyeong Do; Kim, Jong Sung; Lee, Kang Yong

    2008-01-01

    In ASME B and PV Code, Section III, Subsection NB-3600, thermal stratification is not taken into account to determine the peak stress intensity range for fatigue design of nuclear class 1 piping. Therefore, the effects of several parameters such as boundary layer thickness, temperature difference, stratification length, wall thickness, inner diameter and material properties on peak temperature and peak stress intensity due to non-linear temperature distribution of thermal stratification in a pipe cross-section are studied through the numerical parametric study. The results of the parametric study are closely examined and consolidated to introduce an additional term into the equation of ASME so that the modified equation can be used to determine the peak stress intensity range due to all loads including thermal stratification

  17. INVESTIGATIONS ON DESIGN OF HEAT STORAGE PIPE CONNECTIONS FOR SOLAR COMBISYSTEMS

    DEFF Research Database (Denmark)

    Thür, Alexander; Furbo, Simon

    2005-01-01

    This paper describes how different designed pipe connections on a tank for solar combisystems were evaluated based on experimental tests and theoretical investigations with the simulation tool TRNSYS. Measurement results from laboratory measurements were used to calibrate a TRNSYS model....... In general the results showed only very little differences between external connection and internal PEX pipes, if the internal PEX pipes have thick walls. Typically used PEX pipes with only 2 mm wall thickness lead to reduced system performance compared to PEX pipes with 6 mm wall thickness and external pipe...... for simulations with parameter analysis. The possibility to connect pipes at the bottom and use internal PEX pipes to reach the inlet/outlet level in the tank was compared with the possibility to connect the pipe at the side of the tank and pass to the bottom level of the tank inside the tank insulation...

  18. Automatic seismic support design of piping system by an object oriented expert system

    International Nuclear Information System (INIS)

    Nakatogawa, T.; Takayama, Y.; Hayashi, Y.; Fukuda, T.; Yamamoto, Y.; Haruna, T.

    1990-01-01

    The seismic support design of piping systems of nuclear power plants requires many experienced engineers and plenty of man-hours, because the seismic design conditions are very severe, the bulk volume of the piping systems is hyge and the design procedures are very complicated. Therefore we have developed a piping seismic design expert system, which utilizes the piping design data base of a 3 dimensional CAD system and automatically determines the piping support locations and support styles. The data base of this system contains the maximum allowable seismic support span lengths for straight piping and the span length reduction factors for bends, branches, concentrated masses in the piping, and so forth. The system automatically produces the support design according to the design knowledge extracted and collected from expert design engineers, and using design information such as piping specifications which give diameters and thickness and piping geometric configurations. The automatic seismic support design provided by this expert system achieves in the reduction of design man-hours, improvement of design quality, verification of design result, optimization of support locations and prevention of input duplication. In the development of this system, we had to derive the design logic from expert design engineers and this could not be simply expressed descriptively. Also we had to make programs for different kinds of design knowledge. For these reasons we adopted the object oriented programming paradigm (Smalltalk-80) which is suitable for combining programs and carrying out the design work

  19. Report of the US Nuclear Regulatory Commission Piping Review Committee. Volume 2. Evaluation of seismic designs: a review of seismic design requirements for Nuclear Power Plant Piping

    Energy Technology Data Exchange (ETDEWEB)

    1985-04-01

    This document reports the position and recommendations of the NRC Piping Review Committee, Task Group on Seismic Design. The Task Group considered overlapping conservation in the various steps of seismic design, the effects of using two levels of earthquake as a design criterion, and current industry practices. Issues such as damping values, spectra modification, multiple response spectra methods, nozzle and support design, design margins, inelastic piping response, and the use of snubbers are addressed. Effects of current regulatory requirements for piping design are evaluated, and recommendations for immediate licensing action, changes in existing requirements, and research programs are presented. Additional background information and suggestions given by consultants are also presented.

  20. Design and Analysis of Piping System with Supports Using CAESAR-II

    OpenAIRE

    M. Jamuna Rani; K. Ramanathan

    2016-01-01

    A steam power plant is housed with various types of equipments like boiler, turbine, heat exchanger etc. These equipments are mainly connected with piping systems. Such a piping layout design depends mainly on stress analysis and flexibility. It will vary with respect to pipe geometrical properties, pressure, temperature, and supports. The present paper is to analyze the presence and effect of hangers and expansion joints in the piping layout/routing using CAESAR-II software. Main aim of pipi...

  1. Closure Welding Design and Justification for Canister S00645 (Bent Flange)

    International Nuclear Information System (INIS)

    Cannell, G.R.

    1998-01-01

    This report provides the design basis and justification for a closure welding technique using the manual Gas Tungsten Are Welding (GTAW) process. Other aspects affecting closure of Canister S00645, e.g., shielding, facility and administrative requirements, etc., are addressed elsewhere

  2. Design of deepwater HP/HT pipe-in-pipe flowlines crossing mega-furrows in the Gulf of Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Tang, Tianxi Andy; Chacko, Jacob; Zhou, Mengjuan Jane; Omonoji, Gabriel O. [TECHNIP USA, Houston, TX (United States); Eigbe, Uwa [INTECSEA, Houston, TX (United States)

    2009-07-01

    Two 12-mile long pipe-in-pipe (PIP) with HT/HP flow lines were recently designed for the Chinook offshore oil field in the Gulf of Mexico. The routes of the flow line of the Chinook crosses continuous mega-furrows at the water depth ranging from 8200 ft to 8800 ft. The design of the temperature and pressure of the flow lines were 250 deg F and 12,684 psi, respectively. The detailed finite element analysis was performed to predict flow line in-place behavior. The strain-based criterion of API RP 1111 was used where stresses were greater than allowable limits of the ASME B31.8 and found to be satisfactory. The fatigue analysis of the spans pipe subjected to Vortex Induced Vibration (VIV) showed the need for VIV mitigation measures. It was decided that the entire length of the flow lines crossing the mega-furrows should be stake. The analysis of the stake fatigue life of the flow lines resulted greater than the required 25 years service life. Further analysis was performed on the PIP system to optimize the centralizer spacing to sufficiently limit the buckling of inner pipe under operation conditions and prevent crushing of the insulation in the annulus. J-lay analysis of the installation determining the amount of the inner pipe pre-tensioning that was required to eliminate locked-in stresses in the inner and outer pipes. (author)

  3. Design and Fabrication of a Novel Hybrid-Structure Heat Pipe for a Concentrator Photovoltaic

    Directory of Open Access Journals (Sweden)

    Heiu-Jou Shaw

    2012-10-01

    Full Text Available This study presents a design method to fabricate a novel hybrid-structure flat plate heat pipe (NHSP heat pipe for a concentrator photovoltaic. The NHSP heat pipe is composed of a flattened copper pipe and a sintered wick structure, and a coronary-stent-like rhombic copper mesh supports the structure. The coronary-stent-like supporting structure enhances the mechanical strength and shortens the reflux path of the working fluid. Experiments demonstrate that the sintered capillary heat pipe reduces the thermal resistance by approximately 72%, compared to a traditional copper mesh-screen heat pipe. Furthermore, it can reduce thermal resistance by 65% after a supporting structure is added to the heat pipe. The results show that the NHSP heat pipe provided the best performance for the concentrator photovoltaic, which can increase photoelectric conversion efficiency by approximately 3.1%, compared to an aluminum substrate.

  4. Design considerations for CRBRP heat transport system piping operating at elevated temperatures

    International Nuclear Information System (INIS)

    Pollono, L.P.; Mello, R.M.

    1979-01-01

    The heat transport system sodium piping for the Clinch River Breeder Reactor Plant (CRBRP) within the reactor containment building must withstand high temperatures for long periods of time. Each phase of the mechanical design process of the piping system is influenced by elevated temperature considerations which include material thermal creep effects, ratchetting caused by rapid temperature transients and stress relaxation, and material degradation effects. The structural design philosophy taken to design the CRBRP piping operating in a high temperature environment is described. The resulting design of the heat transport system piping is presented along with a discussion of special features that resulted from the elevated temperature considerations

  5. Residual stress evaluation by X-Ray diffraction and hole-drilling in an API 5L X70 steel pipe bent by hot induction

    Energy Technology Data Exchange (ETDEWEB)

    Ceglias, Rodrigo Braga; Alves, Juciane Maria; Botelho, Ramon Alves; Baeta Junior, Eustaquio de Souza; Santos, Igor Cuzzuol dos; Moraes, Nicki Robbers Darciano Cajueiro de; Oliveira, Rebeca Vieira de; Diniz, Saulo Brinco; Brandao, Luiz Paulo, E-mail: brandao@ime.eb.br [Instituto Militar de Engenharia (IME), Rio de Janeiro, RJ (Brazil). Secao de Engenharia Mecanica e de Materiais

    2016-09-15

    The API 5L X70 steel is used in high-pressure gas transmission pipelines. Because of this, knowledge of presence of residual stress and their magnitude is important to assess the material integrity in service. For the pipeline manufacturing, tubes need to be curved which is often made using the hot induction bending process. This process can introduce different residual stress depending of tube position. For this research, in order to evaluate the residual stress, was used an API 5L X70 tube that was previously curved by hot induction process. Samples were taken from the extrados, intrados, neutral line and straight section of the curved tube. Residual stresses were studied by two conventional methods: X-Ray Diffraction (XRD) and Hole-Drilling, which are destructive and non-destructive methods, respectively, in order to assess their qualitative responses. Each of these methods presents particular methodologies in sample preparation and material analysis, but also they differ in factors such time consumption and cost of the analysis. The qualitative responses obtained by the two different methods were comparable and satisfactory and pointed out the existence of a compressive residual stress state in steel pipe. (author)

  6. Seismic design evaluation guidelines for buried piping for the DOE HLW Facilities

    International Nuclear Information System (INIS)

    Lin, Chi-Wen; Antaki, G.; Bandyopadhyay, K.; Bush, S.H.; Costantino, C.; Kennedy, R.

    1995-01-01

    This paper presents the seismic design and evaluation guidelines for underground piping for the Department of Energy (DOE) High-Level-Waste (HLW) Facilities. The underground piping includes both single and double containment steel pipes and concrete pipes with steel lining, with particular emphasis on the double containment piping. The design and evaluation guidelines presented in this paper follow the generally accepted beam-on-elastic-foundation analysis principle and the inertial response calculation method, respectively, for piping directly in contact with the soil or contained in a jacket. A standard analysis procedure is described along with the discussion of factors deemed to be significant for the design of the underground piping. The following key considerations are addressed: the design feature and safety requirements for the inner (core) pipe and the outer pipe; the effect of soil strain and wave passage; assimilation of the necessary seismic and soil data; inertial response calculation for the inner pipe; determination of support anchor movement loads; combination of design loads; and code comparison. Specifications and justifications of the key parameters used, stress components to be calculated and the allowable stress and strain limits for code evaluation are presented

  7. Design of a hot clamp for small diameter LMFBR piping

    International Nuclear Information System (INIS)

    Jones, J.W.; Hamel, D.

    1980-01-01

    In order to evaluate the feasibility of using a strap-type clamp on breeder reactor small diameter piping, a series of analyses were conducted to determine the thermal and mechanical stresses induced in the pipe by the clamp. The effect of using a thin layer of insulation of varying thickness between the pipe and clamp was also investigated. A thermal analysis of the pipe and clamp was conducted for each thermal transient rate. Various insulation values ranging from metal-to-metal condition to perfect insulation between the pipe and clamp were analyzed to determine the effect of insulating the pipe from the clamp. An axisymmetric finite element model was used to determine the axial thermal and stress patterns

  8. Structural and piping issues in the design certification of advanced reactors

    International Nuclear Information System (INIS)

    Ali, S.A.; Terao, D.; Bagchi, G.

    1996-01-01

    The purpose of this paper is to discuss the design certification of structures and piping for evolutionary and passive advanced light water reactors. Advanced reactor designs are based on a set of assumed site-related parameters that are selected to envelop a majority of potential nuclear power plant sites. Multiple time histories are used as the seismic design basis in order to cover the majority of potential sites in the US. Additionally, design are established to ensure that surface motions at a particular site will not exceed the enveloped standard design surface motions. State-of-the-art soil-structure interaction (SSI) analyses have been performed for the advanced reactors, which include structure-to-structure interaction for all seismic Category 1 structures. Advanced technology has been utilized to exclude the dynamic effects of pipe rupture from structural design by demonstrating that the probability of pipe rupture is extremely low. For piping design, the advanced reactor vendors have developed design acceptance criteria (DAC) which provides the piping design analysis methods, design procedures, and acceptance criteria. In SECY-93-087 the NRC staff recommended that the Commission approve the approach to eliminate the OBE from the design of structures and piping in advanced reactors and provided guidance which identifies the necessary changes to existing seismic design criteria. The supplemental criteria address fatigue, seismic anchor motion, and piping stress limits when the OBE is eliminated

  9. Design evaluation on sodium piping system and comparison of the design codes

    International Nuclear Information System (INIS)

    Lee, Dong Won; Jeong, Ji Young; Lee, Yong Bum; Lee, Hyeong Yeon

    2015-01-01

    A large-scale sodium test loop of STELLA-1 (Sodium integral effect test loop for safety simulation and assessment) with two main piping systems has been installed at KAERI. In this study, design evaluations on the main sodium piping systems in STELLA-1 have been conducted according to the DBR (design by rule) codes of the ASME B31.1 and RCC-MRx RB-3600. In addition, design evaluations according to the DBA (design by analysis) code of the ASME Section III Subsection NB-3200 have been conducted. The evaluation results for the present piping systems showed that results from the DBR codes were more conservative than those from the DBA code, and among the DBR codes, the non-nuclear code of the ASME B31.1 was more conservative than the French nuclear DBR code of the RCC-MRx RB-3600. The conservatism on the DBR codes of the ASME B31.1 and RCC-MRx RB-3600 was quantified based on the present sodium piping analyses.

  10. Ship Pipe Routing Design Using NSGA-II and Coevolutionary Algorithm

    Directory of Open Access Journals (Sweden)

    Wentie Niu

    2016-01-01

    Full Text Available Pipe route design plays a prominent role in ship design. Due to the complex configuration in layout space with numerous pipelines, diverse design constraints, and obstacles, it is a complicated and time-consuming process to obtain the optimal route of ship pipes. In this article, an optimized design method for branch pipe routing is proposed to improve design efficiency and to reduce human errors. By simplifying equipment and ship hull models and dividing workspace into three-dimensional grid cells, the mathematic model of layout space is constructed. Based on the proposed concept of pipe grading method, the optimization model of pipe routing is established. Then an optimization procedure is presented to deal with pipe route planning problem by combining maze algorithm (MA, nondominated sorting genetic algorithm II (NSGA-II, and cooperative coevolutionary nondominated sorting genetic algorithm II (CCNSGA-II. To improve the performance in genetic algorithm procedure, a fixed-length encoding method is presented based on improved maze algorithm and adaptive region strategy. Fuzzy set theory is employed to extract the best compromise pipeline from Pareto optimal solutions. Simulation test of branch pipe and design optimization of a fuel piping system were carried out to illustrate the design optimization procedure in detail and to verify the feasibility and effectiveness of the proposed methodology.

  11. 49 CFR 192.123 - Design limitations for plastic pipe.

    Science.gov (United States)

    2010-10-01

    ... in: (1) Distribution systems; or (2) Classes 3 and 4 locations. (b) Plastic pipe may not be used where operating temperatures of the pipe will be: (1) Below −20 °F (−20 °C), or −40 °F (−40 °C) if all... HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY...

  12. Review and assessment of research relevant to design aspects of nuclear power plant piping systems. Final report

    International Nuclear Information System (INIS)

    Rodabaugh, E.C.; Maxey, W.A.; Eiber, R.J.

    1977-06-01

    Significant research on piping systems is evaluated, and the correlation of that research with design practices is presented. The objective is to quantify the research/design practices in terms of the reliability of piping used in nuclear power plants

  13. Research and design of hanger and support series of nuclear safety class process piping

    International Nuclear Information System (INIS)

    Mao Chengzhang; Shi Jiemin

    1995-12-01

    Hangers and supports of nuclear safety class piping are an important part of primary system piping in a nuclear power plant. They will directly affect the reliability of operation, the period at construction and the investment for a nuclear power plant. It is an absolutely necessary job for Pakistan Chashma Nuclear Power Plant Project to research and design a series of piping supports in accordance with ASME-III NF. It is also an important designing for developing nuclear power plant later in China. After working over two years, a series of piping supports of nuclear safety class which have 57 types and more than 2460 specifications have been designed. This series is perfect, and can satisfy the requirements of piping final designing for nuclear power plant. This series of hangers and supports is mainly used in the process piping of nuclear safety class 1,2,3. They can also be used in other piping of nuclear safety class and piping with aseismic requirement of non-nuclear safety class

  14. Basic concepts about application of dual vibration absorbers to seismic design of nuclear piping systems

    International Nuclear Information System (INIS)

    Hara, F.; Seto, K.

    1987-01-01

    The design value of damping for nuclear piping systems is a vital parameter in ensuring safety in nuclear plants during large earthquakes. Many experiments and on-site tests have been undertaken in nuclear-industry developed countries to determine rational design values. However damping value in nuclear piping systems is so strongly influenced by many piping parameters that it shows a tremendous dispersion in its experimental values. A new trend has recently appeared in designing nuclear pipings, where they attempt to use a device to absorb vibration energy induced by seismic excitation. A typical device is an energy absorbing device, made of a special material having a high capacity of plasticity, which is installed between the piping and the support. This paper deals with the basic study of application of dual vibration absorbers to nuclear piping systems to accomplish high damping value and reduce consequently seismic response at resonance frequencies of a piping system, showing their effectiveness from not only numerical calculation but also experimental evaluation of the vibration responses in a 3D model piping system equipped with dual two vibration absorbers

  15. Integrated CAE system for nuclear power plants. Development of piping design check system

    International Nuclear Information System (INIS)

    Narikawa, Noboru; Sato, Teruaki

    1994-01-01

    Toshiba Corporation has developed and operated the integrated CAE system for nuclear power plants, the core of which is the engineering data base to manage accurately and efficiently enormous amount of data on machinery, equipment and piping. As the first step of putting knowledge base system to practical use, piping design check system has been developed. By automatically checking up piping design, this system aims at the prevention of overlooking mistakes, efficient design works and the overall quality improvement of design. This system is based on the thought that it supports designers, and final decision is made by designers. This system is composed of the integrated data base, a two-dimensional CAD system and three-dimensional CAD system. The piping design check system is one of the application systems of the integrated CAE system. Object-oriented programming is the base of the piping design check system, and design knowledge and CAD data are necessary. As to the method of realizing the check system, the flow of piping design, the checkup functions, the checkup of interference and attribute base, and the integration of the system are explained. (K.I)

  16. Vacuum Bellows, Vacuum Piping, Cryogenic Break, and Copper Joint Failure Rate Estimates for ITER Design Use

    Energy Technology Data Exchange (ETDEWEB)

    L. C. Cadwallader

    2010-06-01

    The ITER international project design teams are working to produce an engineering design in preparation for construction of the International Thermonuclear Experimental Reactor (ITER) tokamak. During the course of this work, questions have arisen in regard to safety barriers and equipment reliability as important facets of system design. The vacuum system designers have asked several questions about the reliability of vacuum bellows and vacuum piping. The vessel design team has asked about the reliability of electrical breaks and copper-copper joints used in cryogenic piping. Research into operating experiences of similar equipment has been performed to determine representative failure rates for these components. The following chapters give the research results and the findings for vacuum system bellows, power plant stainless steel piping (amended to represent vacuum system piping), cryogenic system electrical insulating breaks, and copper joints.

  17. Construction of bent functions from near-bent functions

    DEFF Research Database (Denmark)

    Leander, Gregor; McGuire, G.

    2009-01-01

    We give a construction of bent functions in dimension 2m from near-bent functions in dimension 2m - 1. in particular, we give the first ever examples of non-weakly-normal bent functions in dimensions 10 and 12, which demonstrates the significance of our construction.......We give a construction of bent functions in dimension 2m from near-bent functions in dimension 2m - 1. in particular, we give the first ever examples of non-weakly-normal bent functions in dimensions 10 and 12, which demonstrates the significance of our construction....

  18. Advanced concepts, analysis approaches and criteria for nuclear piping system design

    International Nuclear Information System (INIS)

    Tang, H.T.; Tagart, S.W. Jr.; Tang, Y.K.

    1992-01-01

    Recent research in piping system design and analysis has resulted in advancements on damping values, independent support motion (ISM), static coefficient method, simplified inelastic method and ASME code criteria changes. In the support area, passive type of supports such as energy-absorbing device and gap stopper have been developed. These advancements provide bases for improved and cost-effective design of future nuclear piping systems. (author)

  19. Updated pipe break analysis for Advanced Neutron Source Reactor conceptual design

    International Nuclear Information System (INIS)

    Wendel, M.W.; Chen, N.C.J.; Yoder, G.L.

    1994-01-01

    The Advanced Neutron Source Reactor (ANSR) is a research reactor to be built at the Oak Ridge National Laboratory that will supply the highest continuous neutron flux levels of any reactor in the world. It uses plate-type fuel with high-mass-flux and highly subcooled heavy water as the primary coolant. The Conceptual Safety Analysis for the ANSR was completed in June 1992. The thermal-hydraulic pipe-break safety analysis (performed with a specialized version of RELAP5/MOD3) focused primarily on double-ended guillotine breaks of the primary piping and some core-damage mitigation options for such an event. Smaller, instantaneous pipe breaks in the cold- and hot-leg piping were also analyzed to a limited extent. Since the initial analysis for the conceptual design was completed, several important changes to the RELAP5 input model have been made reflecting improvements in the fuel grading and changes in the elevation of the primary coolant pumps. Also, a new philosophy for pipe-break safety analysis (similar to that adopted for the New Production Reactor) accentuates instantaneous, limited flow area pipe-break accidents in addition to finite-opening-time, double-ended guillotine breaks of the major coolant piping. This paper discloses the results of the most recent instantaneous pipe-break calculations

  20. Development of seismic design method for piping system supported by elastoplastic damper. 3. Vibration test of three-dimensional piping model and its response analysis

    International Nuclear Information System (INIS)

    Namita, Yoshio; Kawahata, Jun-ichi; Ichihashi, Ichiro; Fukuda, Toshihiko.

    1995-01-01

    Component and piping systems in current nuclear power plants and chemical plants are designed to employ many supports to maintain safety and reliability against earthquakes. However, these supports are rigid and have a slight energy-dissipating effect. It is well known that applying high-damping supports to the piping system is very effective for reducing the seismic response. In this study, we investigated the design method of the elastoplastic damper [energy absorber (EAB)] and the seismic design method for a piping system supported by the EAB. Our final goal is to develop technology for applying the EAB to the piping system of an actual plant. In this paper, the vibration test results of the three-dimensional piping model are presented. From the test results, it is confirmed that EAB has a large energy-dissipating effect and is effective in reducing the seismic response of the piping system, and that the seismic design method for the piping system, which is the response spectrum mode superposition method using each modal damping and requires iterative calculation of EAB displacement, is applicable for the three-dimensional piping model. (author)

  1. Niobium 1 percent zirconium/potassium and titanium/potassium life-test heat pipe design and testing

    Science.gov (United States)

    Sena, J. Tom; Merrigan, Michael A.

    Experimental lifetime performance studies currently in progress use Niobium 1 percent Zirconium (Nb-1Zr) and Titanium (Ti) heat pipes with potassium (K) as the working fluid. A heat pipe life test matrix was developed for testing the heat pipes. Because the corrosion rates in alkali metal heat pipes are affected by temperature and working fluid evaporation flux, the variable parameters of the experimental matrix are established as steady operating temperature and input heat flux density. Total impurity inventory is a factor in corrosion rate so impurity levels are being evaluated in the heat pipe materials before and after testing. Eight Nb-1Zr/K heat pipes were designed, fabricated, and tested. Two of the heat pipes have completed testing whereas the other six are currently in test. These are gravity assist heat pipes operating in a reflux mode. The heat pipes are tested by sets, one set of two and two sets of three heat pipes. Three Ti/K heat pipes are also in life test. These heat pipes are tested as a set in a horizontal position in a capillary pumped annular flow mode. Each of the heat pipes is encapsulated in a quartz vacuum container with a water calorimeter over the vacuum container for power throughput measurements. Thermocouples are attached to the heat pipes for measuring temperature. Heat input to the heat pipes is via an RF coil. The heat pipes are operating at between 800 and 900 K, with heat input fluxes of 13.8 to 30 W/sq cm. Of the Nb-1Zr/K heat pipes, two of the heat pipes have been in operation for 14,000 hours, three over 10,000 hours, and three over 7,000 hours. The Ti/K heat pipes have been in operation for 1,266 hours.

  2. Design of a Novel In-Pipe Reliable Leak Detector

    OpenAIRE

    Chatzigeorgiou, Dimitrios; Youcef-Toumi, Kamal; Ben-Mansour, Rached

    2013-01-01

    Leakage is the major factor for unaccounted losses in every pipe network around the world (oil, gas, or water). In most cases, the deleterious effects associated with the occurrence of leaks may present serious economical and health problems. Therefore, leaks must be quickly detected, located, and repaired. Unfortunately, most state-of-the-art leak detection systems have limited applicability, are neither reliable nor robust, while others depend on the user experience. In this paper, we prese...

  3. Advances in safety analysis and backfitting design of piping systems

    International Nuclear Information System (INIS)

    Bartholome, G.; Habip, L.M.

    1993-01-01

    Major topics during a safety evaluation of pipework in operating nuclear power stations are external events (e.g. earthquakes) and internal events (e.g. postulated pipe ruptures). Some of the corresponding material and structural mechanics aspects of the integrity of such systems are reviewed. This includes leak-before-break considerations and nonlinear response under strong base excitation or due to simulated breaks and valve closure. (author)

  4. Rigid versus flexible support design: The hidden cost of dynamic response spectrum piping analysis

    International Nuclear Information System (INIS)

    Stevenson, J.D.; Adams, T.M.; Zhao, Y.

    1994-01-01

    Piping System supports designs in late vintage nuclear power plants (construction permits issued 1974--1978) and those supports currently modified are generally based on a stiffness or deflection criteria in addition to the design load. This is done when using the Response Spectrum Modal Analysis Method, due to the analytical requirements that the frequency of each mode be accurately determined, because in a dynamic analysis the loads applied to the piping are frequency dependent. There is no technical requirement to make supports rigid when using the RSMAM analytical procedure, however, most piping system designers have chosen to make them rigid (i.e. the fundamental frequency of the support > 33.0 Hz) rather than compute the actual support stiffnesses and incorporate them in the piping system analysis. For this reason pipe supports are typically being designed as rigid with load carrying capacities 5 to 8 times larger than required to resist calculated loads. Design for stiffness or deflection results in supports which in general cost two to five times more than piping supports which are designed purely for applied load. Presented in this paper are examples of the difference in size and cost between supports designed only for load and those designed for load and a deflection/stiffness criteria. Also briefly discussed are proposed changes to the ASME BPVC, Section 3, Division 1, Appendix N which present a seismic load determination technique which would eliminate the frequency dependency design procedure hence the need to design support for deflection/stiffness criteria and would allow supports to be designed only for load

  5. Development of reliability-based load and resistance factor design methods for piping

    International Nuclear Information System (INIS)

    Ayyub, Bilal M.; Hill, Ralph S. III; Balkey, Kenneth R.

    2003-01-01

    Current American Society of Mechanical Engineers (ASME) nuclear codes and standards rely primarily on deterministic and mechanistic approaches to design. The American Institute of Steel Construction and the American Concrete Institute, among other organizations, have incorporated probabilistic methodologies into their design codes. ASME nuclear codes and standards could benefit from developing a probabilistic, reliability-based, design methodology. This paper provides a plan to develop the technical basis for reliability-based, load and resistance factor design of ASME Section III, Class 2/3 piping for primary loading, i.e., pressure, deadweight and seismic. The plan provides a proof of concept in that LRFD can be used in the design of piping, and could achieve consistent reliability levels. Also, the results from future projects in this area could form the basis for code cases, and additional research for piping secondary loads. (author)

  6. Heat Rejection Systems Utilizing Composites and Heat Pipes: Design and Performance Testing

    Science.gov (United States)

    Jaworske, Donald A.; Beach, Duane E.; Sanzi, James L.

    2007-01-01

    Polymer matrix composites offer the promise of reducing the mass and increasing the performance of future heat rejection systems. With lifetimes for heat rejection systems reaching a decade or more in a micrometeoroid environment, use of multiple heat pipes for fault tolerant design is compelling. The combination of polymer matrix composites and heat pipes is of particular interest for heat rejection systems operating on the lunar surface. A technology development effort is under way to study the performance of two radiator demonstration units manufactured with different polymer matrix composite face sheet resin and bonding adhesives, along with different titanium-water heat pipe designs. Common to the two radiator demonstration units is the use of high thermal conductivity fibers in the face sheets and high thermal conductivity graphite saddles within a light weight aluminum honeycomb core. Testing of the radiator demonstration units included thermal vacuum exposure and thermal vacuum exposure with a simulated heat pipe failure. Steady state performance data were obtained at different operating temperatures to identify heat transfer and thermal resistance characteristics. Heat pipe failure was simulated by removing the input power from an individual heat pipe in order to identify the diminished performance characteristics of the entire panel after a micrometeoroid strike. Freeze-thaw performance was also of interest. This paper presents a summary of the two radiator demonstration units manufactured to support this technology development effort along with the thermal performance characteristics obtained to date. Future work will also be discussed.

  7. Flexible Heat Pipe

    Science.gov (United States)

    Bienert, W. B.; Wolf, D. A.

    1985-01-01

    Narrow Tube carries 10 watts or more to moving parts. Heat pipe 12 inches long and diameter of 0.312 inch (7.92mm). Bent to minimum radius of 2.5 blocks. Flexible section made of 321 stainless steel tubing (Cajon Flexible Tubing or equivalent). Evaporator and condenser made of oxygen free copper. Working fluid methanol.

  8. Comparative analysis study for piping seismic design criteria. Part 1: Methodology and objectives

    International Nuclear Information System (INIS)

    Adams, T.M.; Branch, E.B.; Landers, D.F.; Tagart, S.W. Jr.

    1994-01-01

    As part of the First of a Kind Engineering effort for the Advanced Light Water Reactor the Advanced Reactor Corporation formed a Piping Technical Core Group to develop a set of improved ASME Boiler and Pressure Vessel Code, Section III design rules and approaches for ALWR plant piping and support design. In developing this proposed criteria the Technical Core Group conducted an extensive Comparative Analysis Study of many of the eighteen proposals for new or alternative seismic piping design criteria under consideration by The ASME Code Committee. As part of this comparative study the Technical Core Group also devised a process for determining the relative conservatism of each design criteria studied. In addition a method to relate these relative margins to EPRI/USNRC piping component test margins was developed which allows an assessment of the minimum margin to failure that could be expected from each set of design rules and criteria studied. The study was conducted in two phases and the methodology for each of these phases is presented. Phase 1 was done to develop the relative margins and relate these margins to the actual EPRI/USNRC test data. Phase 2 was done to study the optimized support configurations which could be created using each of the different criteria reviewed. Also, presented in this paper is a discussion of the different criteria selected for study, Analysis Methods/Criteria applied, the piping models for the study, and the specific inputs for the comparative analyses

  9. At-sea test system point design for a one-third scale cold water pipe

    Energy Technology Data Exchange (ETDEWEB)

    Sutherland, W.H. (ed.)

    1979-12-01

    One step in the development of the technology for Ocean Thermal Energy Conversion (OTEC) Cold Water Pipes (CWP) is the at-sea testing of a fiberglass reinforced plastic nominal 10-foot diameter pipe. A design procedure and criteria for developing test hardware by scaling down a 30-foot diameter OTEC 10/40 MW Pilot Plant CWP design are presented. An example point design for the pipe, instrumentation to be used during the at-sea tests, and methods for selecting the support platform and mooring are described. The design considered starts with a scale model of a larger prototype, and then is modified to address the problems of fabrication and of survivability and handling during the 1/3rd scale model tests.

  10. Development of expert system for piping design in nuclear power stations

    International Nuclear Information System (INIS)

    Suwa, Minoru; Saito, Shunji; Nakagawa, Hiroshi; Mazaki, Tatsuya; Hirato, Miharu; Masaka, Shuzo; Hori, Hiromi

    1990-01-01

    Design engineers for piping in nuclear power stations have to pay special attention to safety and reliability, and account for specific requirements such as system functions, plant operability and structural strength. The large amount of pipes used over 500 km in length requires many expertized engineers for its design and many hours of effort for engineering. IHI has already effectively applied integrated computer systems for productional engineering. These efforts have greatly effected on stability in design and savings in manpower. Currently, it is remarkable that expert systems which utilize the technology of artificial intelligence are being utilized in various fields. IHI developed the expert system in order to deal with the complicated piping design in nuclear power stations. This paper described the outline of the expert system which was completed as the prototype. (author)

  11. Design and analysis of push pipe joint under internal pressure and temperature loading

    International Nuclear Information System (INIS)

    Abid, M.; Alam, K.

    2005-01-01

    Pipe joints flanged or welded are commonly used in industry for different applications ranging from sewerage to the high pressure and temperature applications. However, with the rapidly changing technological trends, for optimized space such as for heat exchanger applications, pipe joint design needs special consideration, especially for the internal pipe where no flanged/bolted joint due to space constraint can be used. In addition, where joint opening/closing is the requirement for maintenance or other functional purposes, it becomes inevitable to use some special design. In this paper, a push joint proposed is designed, analyzed, optimized and tested for safe stress and operating conditions. An experimental test rig is designed and tests are performed for internal pressure and temperature separately and joint's behaviour is analyzed in detail for any leaks. FEA results are compared and verified with the mathematical results. Based on the experimental observations, the joint is safe as no leaks are observed. (author)

  12. IEEE recommended practice for the design and installation of electric pipe heating systems for nuclear power generating stations

    International Nuclear Information System (INIS)

    Anon.

    1979-01-01

    The realization that electric pipe heating systems play an important role in the normal operation of both nuclear and non-nuclear processes in nuclear power generating stations is now coming of age. This is apparent by the increased amount of space being devoted to electric pipe heating in station technical specifications, system descriptions, and operating criteria. Such electric pipe heating systems are applied on borated water systems and on water treatment systems such as caustic. Since boric acid and caustics in water will crystalize or precipitate out of the solution, depending on their concentrations at temperatures above ambient, and since such crystallization can make the piping system inoperable for normal operation, electric pipe heating systems are required to keep the solutions and piping systems in a state to perform their intended functions. Electric pipe heating systems may also be applied on piping located outdoors at nuclear generating stations for the purpose of preventing the piping systems from freezing. It should be noted that each and all of these piping systems can include valves, pumps, strainers, tanks, and instrumentation components that can be rendered inoperable due to solutions crystalizing or freezing. Therefore, a definite need exists within the nuclear power industry for recommendations that provide a uniform method for the design and installation of electric pipe heating systems that meet the requirements for rendering reliable operation of the piping system. Without such recommendations, station reliability may be jeopardized

  13. Multiobjective optimization for design of multifunctional sandwich panel heat pipes with micro-architected truss cores

    International Nuclear Information System (INIS)

    Roper, Christopher S.

    2011-01-01

    A micro-architected multifunctional structure, a sandwich panel heat pipe with a micro-scale truss core and arterial wick, is modeled and optimized. To characterize multiple functionalities, objective equations are formulated for density, compressive modulus, compressive strength, and maximum heat flux. Multiobjective optimization is used to determine the Pareto-optimal design surfaces, which consist of hundreds of individually optimized designs. The Pareto-optimal surfaces for different working fluids (water, ethanol, and perfluoro(methylcyclohexane)) as well as different micro-scale truss core materials (metal, ceramic, and polymer) are determined and compared. Examination of the Pareto fronts allows comparison of the trade-offs between density, compressive stiffness, compressive strength, and maximum heat flux in the design of multifunctional sandwich panel heat pipes with micro-scale truss cores. Heat fluxes up to 3.0 MW/m 2 are predicted for silicon carbide truss core heat pipes with water as the working fluid.

  14. Design rules for piping: Plastic stability of straight parts under level D loadings

    International Nuclear Information System (INIS)

    Touboul, F.; Ben Djidia, M.; Acker, D.

    1989-01-01

    Design rules for piping, elaborated for Fast Breeder Reactors, are based on analysis performed for Pressure Water Reactors. Interpretation of largely diversified straight parts tests, enable us to validate and improve existing rules and to propose a more suitable formula. Design rules for piping appear to be non conservative for austenitic thin tubes in bending or torsion. By introducing a B 2 coefficient, geometrically dependent, the gap between thin and thick tubes may be withheld. Conservatism of rules can be ensured by considering the allowable stress defined by ASME, Section III, Appendix F

  15. Use of probabilistic techniques in designing pipes and pressure vessels

    International Nuclear Information System (INIS)

    Wells, J.E.

    1974-01-01

    Probabilistic techniques are described that enable the design engineer to make reliability estimations during the design phase based on variability evaluations of quantitative design parameters. Statistical distributions are discussed for stress and strength, and techniques are presented for incorporating these distributions into the design process. The use of statistical techniques in fracture mechanics is also discussed. (U.S.)

  16. Channeling through Bent Crystals

    Energy Technology Data Exchange (ETDEWEB)

    Mack, Stephanie; /Ottawa U. /SLAC

    2012-09-07

    Bent crystals have demonstrated potential for use in beam collimation. A process called channeling is when accelerated particle beams are trapped by the nuclear potentials in the atomic planes within a crystal lattice. If the crystal is bent then the particles can follow the bending angle of the crystal. There are several different effects that are observed when particles travel through a bent crystal including dechanneling, volume capture, volume reflection and channeling. With a crystal placed at the edge of a particle beam, part of the fringe of the beam can be deflected away towards a detector or beam dump, thus helping collimate the beam. There is currently FORTRAN code by Igor Yazynin that has been used to model the passage of particles through a bent crystal. Using this code, the effects mentioned were explored for beam energy that would be seen at the Facility for Advanced Accelerator Experimental Tests (FACET) at a range of crystal orientations with respect to the incoming beam. After propagating 5 meters in vacuum space past the crystal the channeled particles were observed to separate from most of the beam with some noise due to dechanneled particles. Progressively smaller bending radii, with corresponding shorter crystal lengths, were compared and it was seen that multiple scattering decreases with the length of the crystal therefore allowing for cleaner detection of the channeled particles. The input beam was then modified and only a portion of the beam sent through the crystal. With the majority of the beam not affected by the crystal, most particles were not deflected and after propagation the channeled particles were seen to be deflected approximately 5mm. After a portion of the beam travels through the crystal, the entire beam was then sent through a quadrupole magnet, which increased the separation of the channeled particles from the remainder of the beam to a distance of around 20mm. A different code, which was developed at SLAC, was used to

  17. Seismic design of equipment and piping systems for nuclear power plants in Japan

    International Nuclear Information System (INIS)

    Minematsu, Akiyoshi

    1997-01-01

    The philosophy of seismic design for nuclear power plant facilities in Japan is based on 'Examination Guide for Seismic Design of Nuclear Power Reactor Facilities: Nuclear Power Safety Committee, July 20, 1981' (referred to as 'Examination Guide' hereinafter) and the present design criteria have been established based on the survey of governmental improvement and standardization program. The detailed design implementation procedure is further described in 'Technical Guidelines for Aseismic Design of Nuclear Power Plants, JEAG4601-1987: Japan Electric Association'. This report describes the principles and design procedure of the seismic design of equipment/piping systems for nuclear power plant in Japan. (J.P.N.)

  18. Seismic design of equipment and piping systems for nuclear power plants in Japan

    Energy Technology Data Exchange (ETDEWEB)

    Minematsu, Akiyoshi [Tokyo Electric Power Co., Inc. (Japan)

    1997-03-01

    The philosophy of seismic design for nuclear power plant facilities in Japan is based on `Examination Guide for Seismic Design of Nuclear Power Reactor Facilities: Nuclear Power Safety Committee, July 20, 1981` (referred to as `Examination Guide` hereinafter) and the present design criteria have been established based on the survey of governmental improvement and standardization program. The detailed design implementation procedure is further described in `Technical Guidelines for Aseismic Design of Nuclear Power Plants, JEAG4601-1987: Japan Electric Association`. This report describes the principles and design procedure of the seismic design of equipment/piping systems for nuclear power plant in Japan. (J.P.N.)

  19. Design demonstrations for Category B tank system piping at Oak Ridge National Laboratory, Oak Ridge, Tennessee

    International Nuclear Information System (INIS)

    1994-02-01

    Demonstration of the design of the tank systems described in this report is stipulated by the Federal Facility Agreement (FFA) between the U.S. Environmental Protection Agency-Region IV, the Tennessee Department of Environment and Conservation, and the U.S. Department of Energy. This report provides a design demonstration of the secondary containment and ancillary equipment of 30 piping systems listed in the FFA as Category B (i.e., existing tank systems with secondary containment). The design demonstrations were developed using information obtained from design drawings (as-built when available), construction specifications, and interviews with facility operators. Each design demonstration addresses system conformance to the requirements of the FFA (Appendix F, Section C). Deficiencies or restrictions regarding the ability to demonstrate that each of the containment systems conforms to FFA requirements are noted in the discussion of each piping system

  20. Ocean thermal energy conversion cold water pipe preliminary design project. Appendices to final report

    Energy Technology Data Exchange (ETDEWEB)

    1979-11-20

    NOAA/DOE has selected three concepts for a baseline design of the cold water pipe (CWP) for OTEC plants: (1) a FRP CWP of sandwich wall construction suspended from the Applied Physical Laboratory/John Hopkins University (APL/JHU) barge at a site 200 miles east of the coast of Brazil using a horizontal deployment scheme; (2) an elastomer CWP suspended from the APL/JHU barge off the southeast coast of Puerto Rico using either a horizontal or vertical deployment scheme; and (3) a polyethylene CWP (single or multiple pipe) suspended from the Gibbs and Cox spar at the Puerto Rico site using a horizontal deployment scheme. TRW has developed a baseline design for each of these configurations. This volume of the report includes the following appendices: (A) fiberglass reinforced plastic cold water pipe (specification and drawingss); (B) specification for polyethylene CWP; (C) elastomer pipe drawings; (D) drawings for OTEC 10/40 hull/CWP transitions; (E) structural design of OTEC 10/40 CWP support and CWP transitions; (F) universal transition joint for CWP; (G) dynamic spherical seal of CWP; (H) at-sea deployment loads - surface towing loads; (I) OTEC 10/40 CWP deployment up-ending loads; (J) cost estimates for OTEC 10/40 hull/CWP transitions; and (K) OTEC 10/40 CWP deployment scenario and cost estimate. (WHK)

  1. Design demonstrations for Category B tank systems piping at Oak Ridge National Laboratory, Oak Ridge, Tennessee

    International Nuclear Information System (INIS)

    1994-12-01

    Demonstration of the design of the piping systems described in this report is stipulated by the Federal Facility Agreement (FFA) between the U.S. Environmental Protection Agency (EPA)-Region IV, the Tennessee Department of Environment and Conservation (TDEC), and the U.S. Department of Energy (DOE). This report provides a design demonstration of the secondary containment and ancillary equipment of 30 piping systems designated in the FFA as Category B (i.e., existing tank systems with secondary containment). Based on the findings of the Design Demonstrations for the Remaining 19 Category B Tank Systems, (DOE/OR/03-1150 ampersand D2), three tank systems originally designated as Category B have been redesignated as Category C (i.e., existing tank systems without secondary containment). The design demonstrations were developed using information obtained from design drawings (as-built when available), construction specifications, and interviews with facility operators. Each design demonstration addresses system conformance to the requirements of the FFA (Appendix F, Section C). Deficiencies or restrictions regarding the ability to demonstrate that each of the containment systems conforms to FFA requirements are noted in the discussion of each piping system and presented in Table 2.0-1

  2. Drop on a bent fibre.

    Science.gov (United States)

    Pan, Zhao; Weyer, Floriane; Pitt, William G; Vandewalle, Nicolas; Truscott, Tadd T

    2018-03-15

    Inspired by the huge droplets attached on cypress tree leaf tips after rain, we find that a bent fibre can hold significantly more water in the corner than a horizontally placed fibre (typically up to three times or more). The maximum volume of the liquid that can be trapped is remarkably affected by the bending angle of the fibre and surface tension of the liquid. We experimentally find the optimal included angle (∼36°) that holds the most water. Analytical and semi-empirical models are developed to explain these counter-intuitive experimental observations and predict the optimal angle. The data and models could be useful for designing microfluidic and fog harvesting devices.

  3. On fundamental concept of anti-earthquake design of equipment and pipings

    International Nuclear Information System (INIS)

    Shibata, H.; Kato, M.

    1979-01-01

    This paper deals with a new concept of anti-earthquake design of equipment and pipings in nuclear power plants. Usual anti-earthquake design of such items starts from the design basis ground motions, via floor responses and ends at the stress analysis of each structural element. However, the same type of equipment are used for plants under various site conditions. The ordinarily used method obliges the repetition of such design procedure on each plant. This new design method has been developed to avoid such time-consuming repetitions. (orig.)

  4. State-of-the-Art Report on the Piping and Instrumentation Design of RHRS in the Commercial NPPs

    International Nuclear Information System (INIS)

    Lee, Jun; Park, C. T.; Kim, Y. I.; Kim, S. H.; Choi, B. S.; Yoon, Ju Hyeon

    2004-12-01

    The objective of the study is for system designers to understand the technical state of the piping and instrumentation design of RHRS (or SCS) in the commercial nuclear power plants, thus to design more uncomplicated and advanced system. In this study, we have reviewed the design requirements and the technical state of piping and instrumentation design. Firstly we have reviewed the design requirements, including functional, isolation, pressure relief, pump protection, test requirements, etc.. Especially we have separately reviewed the design requirements of the low temperature overpressure, including ASME code requirements. Also we have reviewed the technical state of piping and instrumentation design, including piping design, PAMS design, ESFAS design, relief valve design, and instrument/valve/pump control design. In the piping design, the technical state of design has been investigated classified by the five regions, which have a little different design features, from the RCS suction line to the LPSI header line. Commonly, the P and ID is the design output which the related design requirements of the system have been all applied, also the operations for in-service inspection, heat-up/normal/cool-down, and emergency have been all considered. If we can understand well the design bases and its meanings of the P and ID, it would be helpful for us to design more uncomplicated and advanced system

  5. On bent and semi-bent quadratic Boolean functions

    DEFF Research Database (Denmark)

    Charpin, P.; Pasalic, Enes; Tavernier, C.

    2005-01-01

    their results to even n. We further investigate the conditions on the choice of ci for explicit definitions of new infinite families having three and four trace terms. Also, a class of nonpermutation polynomials whose composition with a quadratic function yields again a quadratic semi-bent function is specified...... correlation and high nonlinearity. We say that such a sequence is generated by a semi-bent function. Some new families of such function, represented by f(x) = Sigma(i=1)(n-1/2) c(i)Tr(x(2t+1)), n odd and c(i) is an element of F-2, have recently (2002) been introduced by Khoo et al. We first generalize....... The treatment of semi-bent functions is then presented in a much wider framework. We show how bent and semi-bent functions are interlinked, that is, the concatenation of two suitably chosen semi-bent functions will yield a bent function and vice versa. Finally, this approach is generalized so...

  6. Shield For Flexible Pipe

    Science.gov (United States)

    Ponton, Michael K.; Williford, Clifford B.; Lagen, Nicholas T.

    1995-01-01

    Cylindrical shield designed to fit around flexible pipe to protect nearby workers from injury and equipment from damage if pipe ruptures. Designed as pressure-relief device. Absorbs impact of debris ejected radially from broken flexible pipe. Also redirects flow of pressurized fluid escaping from broken pipe onto flow path allowing for relief of pressure while minimizing potential for harm.

  7. Clues from Bent Jets

    Science.gov (United States)

    Kohler, Susanna

    2018-04-01

    Powerful jets emitted from the centers of distant galaxies make for spectacular signposts in the radio sky. Can observations of these jets reveal information about the environments that surround them?Signposts in the SkyVLA FIRST images of seven bent double-lobed radio galaxies from the authors sample. [Adapted from Silverstein et al. 2018]An active supermassive black hole lurking in a galactic center can put on quite a show! These beasts fling out accreting material, often forming intense jets that punch their way out of their host galaxies. As the jets propagate, they expand into large lobes of radio emission that we can spot from Earth observable signs of the connection between distant supermassive black holes and the galaxies in which they live.These distinctive double-lobed radio galaxies (DLRGs) dont all look the same. In particular, though the jets are emitted from the black holes two poles, the lobes of DLRGs dont always extend perfectly in opposite directions; often, the jets become bent on larger scales, appearing to us to subtend angles of less than 180 degrees.Can we use our observations of DLRG shapes and distributions to learn about their surroundings? A new study led by Ezekiel Silverstein (University of Michigan) has addressed this question by exploring DLRGs living in dense galaxy-cluster environments.Projected density of DLRGcentral galaxy matches (black) compared to a control sample of random positionscentral galaxy matches (red) for different distances from acluster center. DLRGs have a higher likelihood of being located close to a cluster center. [Silverstein et al. 2018]Living Near the HubTo build a sample of DLRGs in dense environments, Silverstein and collaborators started from a large catalog of DLRGs in Sloan Digital Sky Survey quasars with radio lobes visible in Very Large Array data. They then cross-matched these against three galaxy catalogs to produce a sample of 44 DLRGs that are each paired to a nearby massive galaxy, galaxy group

  8. Design and manufacture of ceramic heat pipes for high temperature applications

    International Nuclear Information System (INIS)

    Meisel, Peter; Jobst, Matthias; Lippmann, Wolfgang; Hurtado, Antonio

    2015-01-01

    Heat exchangers based on ceramic heat pipes were designed for use under highly abrasive and corrosive atmospheres at temperatures in the range of 800–1200 °C for high-temperature power-engineering applications. The presented heat pipes are gravity assisted and based on a multi-layer concept comprising a ceramic cladding and an inner metal tube that contains sodium as the working fluid. Hermetical encapsulation of the working fluid was achieved by electron-beam welding of the inner metal tube. Subsequently, closure of the surrounding ceramic tube was performed by laser brazing technology using a glass solder. Temperature resistance and functionality of the manufactured ceramic thermosyphons could be confirmed experimentally in a hot combustion gas atmosphere at temperatures up to 1100 °C. The ceramic tubes used had an outer diameter of 22 mm and a total length of 770 mm. The measured axial heat transfer of the ceramic gravity assisted heat pipes at the stationary operating point with cold/hot gas temperature of 100 °C/900 °C was 400 W. The result of the calculation using the created mathematical model amounted to 459 W. - Highlights: • Heat-pipe design consists of a ceramic shell and an inner metallic tube. • Laser brazing technology is suitable to seal ceramic heat-pipes. • Thermal characteristic of double wall thermosyphon was modelled using FEM code. • Experimental investigations demonstrated functionality of double wall thermosyphons

  9. Reliability based code calibration of fatigue design criteria of nuclear Class-1 piping

    International Nuclear Information System (INIS)

    Mishra, J.; Balasubramaniyan, V.; Chellapandi, P.

    2016-01-01

    Fatigue design of Class-l piping of NPP is carried out using Section-III of American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel code. The fatigue design criteria of ASME are based on the concept of safety factor, which does not provide means for the management of uncertainties for consistently reliable and economical designs. In this regards, a work is taken up to estimate the implicit reliability level associated with fatigue design criteria of Class-l piping specified by ASME Section III, NB-3650. As ASME fatigue curve is not in the form of analytical expression, the reliability level of pipeline fittings and joints is evaluated using the mean fatigue curve developed by Argonne National Laboratory (ANL). The methodology employed for reliability evaluation is FORM, HORSM and MCS. The limit state function for fatigue damage is found to be sensitive to eight parameters, which are systematically modelled as stochastic variables during reliability estimation. In conclusion a number of important aspects related to reliability of various piping product and joints are discussed. A computational example illustrates the developed procedure for a typical pipeline. (author)

  10. The 1994 Forum on Appropriate Criteria and Methods for Seismic Design of Nuclear Piping

    International Nuclear Information System (INIS)

    Slagis, G.C.

    1995-01-01

    A record of the 1994 Forum on Appropriate Criteria and Methods for Seismic Design of Nuclear Piping is provided. The focus of the forum was the design-by-rule method for seismic design of piping. Issues such as acceptance criteria, ductility considerations, demonstration of margin, training, verification and costs were discussed. The use of earthquake experience data, including the recent Northridge earthquake, to justify a design-by-rule method was explored. The majority of the participants felt there are not significant advantages to developing a design-by-rule approach for new plant design. One major disadvantage was considered by many to be training. Extensive training will be required to properly implement a design-by-rule approach. Verification of designs was considered by the majority to be equally important for design-by-rule as for design-by-analysis. If a design-by-rule method is going to be effective, the method will have to be based on ductility considerations (UBC approach). A significant issue will be justification of seismic margins with liberal rules. The UBC approach is being questioned by some because of the recent structural cracking problems in the Northridge earthquake

  11. Optimum Design of FGX-CNT-Reinforced Reddy Pipes Conveying Fluid Subjected to Moving Load

    Directory of Open Access Journals (Sweden)

    Farid Vakili Tahami

    2016-12-01

    Full Text Available The harmony search algorithm is applied to the optimum designs of functionally graded (FG-carbon nanotubes (CNTs-reinforced pipes conveying fluid which are subjected to a moving load. The structure is modeled by the Reddy cylindrical shell theory, and the motion equations are derived by Hamilton's principle. The dynamic displacement of the system is derived based on the differential quadrature method (DQM. Moreover, the length, thickness, diameter, velocity, and acceleration of the load, the temperature and velocity of the fluid, and the volume fraction of CNT are considered for the design variables. The results illustrate that the optimum diameter of the pipe is decreased by increasing the volume percentage of CNTs. In addition, by increasing the moving load velocity and acceleration, the FS is decreased.

  12. Piping design and analysis: comparison between the Belgian applications of French and American rules

    International Nuclear Information System (INIS)

    Daoust, Ph.; Geraets, L.H.; Lafaille, J.P.

    1989-01-01

    In the process of a feasibility study of a new nuclear power plant in Belgium, the French and American rules for piping design have been compared. The Belgian method rests on the American nuclear set of rules and uses the ASME code. French rules were initially based on the American rules (1978). Subsequent individual development led to a differentiation of the rules. Presently, the mechanical part of the French rules is mainly contained in the RCCP ('Regles de Conception et de Construction relatives aux Procedes') and the RCCM ('Regles de Conception et de Construction des materiels Mecaniques'). This paper compares the piping design rules from a general point of view; examples of applications allow benefits or drawbacks of the use of ASME or RCCM codes to identified. (author)

  13. Fabrication of mechanical components and piping design for Brazilian nuclear reactors

    International Nuclear Information System (INIS)

    Deppe, L.O.

    1987-01-01

    The supply of Brazilian equipment and piping design for Angra 2 (and Angra 3 in some cases) have reached an advanced status in spite of the continuous outside difficulties which affect these nuclear power plants. The achieved quality is similar to the quality achieved in foreign countries and the nationalization program foreseen in 1975 is being largely surpassed. In this paper the actual situation is presented as well as the future perspectives. (Author) [pt

  14. Parametrical analysis of the design and performance of a solar heat pipe thermoelectric generator unit

    International Nuclear Information System (INIS)

    He, Wei; Su, Yuehong; Riffat, S.B.; Hou, JinXin; Ji, Jie

    2011-01-01

    Highlights: → An analytical model of SHP-TEG unit for the condition of constant solar irradiation. → Simulation of maximum power output and conversion efficiency of SHP-TEG. → Design optimization of SHP-TEG. -- Abstract: This paper describes a solar heat pipe thermoelectric generator (SHP-TEG) unit comprising an evacuated double-skin glass tube, a finned heat pipe and a TEG module. The system takes the advantage of heat pipe to convert the absorbed solar irradiation to a high heat flux to meet the TEG operating requirement. An analytical model of the SHP-TEG unit is presented for the condition of constant solar irradiation, which may lead to different performance characteristics and optimal design parameters compared with the condition of constant temperature difference usually dealt with in other studies. The analytical model presents the complex influence of basic parameters such as solar irradiation, cooling water temperature, thermoelement length and cross-section area and number of thermoelements, etc. on the maximum power output and conversion efficiency of the SHP-TEG. Simulation based on the analytical model has been carried out to study the performance and design optimization of the SHP-TEG.

  15. Thermal design heat sinks, thermoelectrics, heat pipes, compact heat exchangers, and solar cells

    CERN Document Server

    Lee, H S

    2010-01-01

    The proposed is written as a senior undergraduate or the first-year graduate textbook,covering modern thermal devices such as heat sinks, thermoelectric generators and coolers, heat pipes, and heat exchangers as design components in larger systems. These devices are becoming increasingly important and fundamental in thermal design across such diverse areas as microelectronic cooling, green or thermal energy conversion, and thermal control and management in space, etc. However, there is no textbook available covering this range of topics. The proposed book may be used as a capstone design cours

  16. Design and Operation of a Cryogenic Nitrogen Pulsating Heat Pipe

    International Nuclear Information System (INIS)

    Fonseca, Luis Diego; Miller, Franklin; Pfotenhauer, John

    2015-01-01

    We report the design, experimental setup and successful test results using an innovative passive cooling system called a “Pulsating Heat Pipe” (PHP) operating at temperatures ranging from 77 K to 80 K and using nitrogen as the working fluid. PHPs, which transfer heat by two phase flow mechanisms through a closed loop tubing have the advantage that no electrical pumps are needed to drive the fluid flow. In addition, PHPs have an advantage over copper straps and thermal conductors since they are lighter in weight, exhibit lower temperature gradients and have higher heat transfer rates. PHPs consist of an evaporator section, thermally anchored to a solid, where heat is received at the saturation temperature where the liquid portion of the two-phase flow evaporates, and a condenser where heat is rejected at the saturation temperature where the vapor is condensed. The condenser section in our experiment has been thermally interfaced to a CT cryocooler from SunPower that has a cooling capacity of 10 W at 77 K. Alternating regions of liquid slugs and small vapor plugs fill the capillary tubing, with the vapor regions contracting in the condenser section and expanding in the evaporator section due to an electric heater that will generate heat loads up to 10 W. This volumetric expansion and contraction provides the oscillatory flow of the fluid throughout the capillary tubing thereby transferring heat from one end to the other. The thermal performance and temperature characteristics of the PHP will be correlated as a function of average condenser temperature, PHP fill liquid ratio, and evaporator heat load. The experimental data show that the heat transfer between the evaporator and condenser sections can produce an effective thermal conductivity up to 35000 W/m-K at a 3.5 W heat load. (paper)

  17. A new construction of bent functions based on Z-bent functions

    DEFF Research Database (Denmark)

    Gangopadhyay, Sugata; Joshi, Anand; Leander, Gregor

    2013-01-01

    Dobbertin has embedded the problem of construction of bent functions in a recursive framework by using a generalization of bent functions called -bent functions. Following his ideas, we generalize the construction of partial spreads bent functions to partial spreads -bent functions of arbitrary...

  18. Method for optimal design of pipes for low-energy district heating, with focus on heat losses

    DEFF Research Database (Denmark)

    Dalla Rosa, Alessandro; Li, Hongwei; Svendsen, Svend

    2011-01-01

    factors in the optimal design of low-energy DH systems. Various pipe configurations are considered in this paper: flexible pre-insulated twin pipes with symmetrical or asymmetrical insulation, double pipes, and triple pipes. These technologies represent potential energy-efficient and cost......-effective solutions for DH networks in low-heat density areas. We start with a review of theories and methods for steady-state heat loss calculation. Next, the article shows how detailed calculations with 2D-modeling of pipes can be carried out by means of computer software based on the finite-element method (FEM......). The model was validated by comparison with experimental measurements, analytical formulas, and data from the literature. We took into account the influence of the temperature-dependent conductivity coefficient of polyurethane insulation foam, which enabled us to achieve a high degree of accuracy. We also...

  19. Design, development and test of a capillary pump loop heat pipe

    Science.gov (United States)

    Kroliczek, E. J.; Ku, J.; Ollendorf, S.

    1984-06-01

    The development of a capillary pump loop (CPL) heat pipe, including computer modeling and breadboard testing, is presented. The computer model is a SINDA-type thermal analyzer, combined with a pressure analyzer, which predicts the transients of the CPL heat pipe during operation. The breadboard is an aluminum/ammonia transport system which contains multiple parallel evaporator and condenser zones within a single loop. Test results have demonstrated the practicality and reliability of such a design, including heat load sharing among evaporators, liquid inventory/temperature control feature, and priming under load. Transport capability for this system is 65 KW-M with individual evaporator pumps managing up to 1.7 KW at a heat flux of 15 W/sq cm. The prediction of the computer model for heat transport capabilities is in good agreement with experimental results.

  20. Imaging with Spherically Bent Crystals or Reflectors

    Energy Technology Data Exchange (ETDEWEB)

    Bitter, M; Hill, K W; Scott, S; Ince-Cushman, A; Reinke, M; Podpaly, Y; Rice, J E; Beiersdorfer, P

    2010-06-01

    This paper consists of two parts: Part I describes the working principle of a recently developed x-ray imaging crystal spectrometer, where the astigmatism of spherically bent crystals is being used with advantage to record spatially resolved spectra of highly charged ions for Doppler measurements of the ion-temperature and toroidal plasmarotation- velocity profiles in tokamak plasmas. This type of spectrometer was thoroughly tested on NSTX and Alcator C-Mod, and its concept was recently adopted for the design of the ITER crystal spectrometers. Part II describes imaging schemes, where the astigmatism has been eliminated by the use of matched pairs of spherically bent crystals or reflectors. These imaging schemes are applicable over a wide range of the electromagnetic radiation, which includes microwaves, visible light, EUV radiation, and x-rays. Potential applications with EUV radiation and x-rays are the diagnosis of laserproduced plasmas, imaging of biological samples with synchrotron radiation, and lithography.

  1. Space qualification of high capacity grooved heat pipes

    Energy Technology Data Exchange (ETDEWEB)

    Dubois, M.; Mullender, B.; Druart, J. [SABCA, Societe Anomyme Belgel de Construction Aeronautique (Belgium); Supper, W.; Beddows, A. [ESTEC-The (Netherlands)

    1996-12-31

    Based on the thermal requirements of the future telecommunication satellites, the development of a High Capacity Grooved Heat Pipe (HPG), was contracted by ESA to SABCA leading to an aluminium extruded heat pipe (outer diameter of 25 mm) based on a multi re-entrant grooves design. After an intensive acceptance test campaign whose results showed a good confidence in the design and the fulfillment of the required specifications of heat transport and on tilt capability (experimental maximum heat transport capability of 1500 Watt metres for a vapour temperature of 20 deg C), similar heat pipes have been developed with various outer diameters (11 mm, 15 mm and 20 mm) and with various shapes (circular outer shapes, integrated saddles). Several of these heat pipes were tested during two parabolic flight campaigns, by varying the heat loads during the micro-gravity periods. This HGP heat pipe family is now being submitted to a space qualification program according to ESA standards (ESA PSS-49), both in straight and bent configuration. Within this qualification, the heat pipes are submitted to an extended test campaign including environmental (random/sinus vibration, constant acceleration) and thermal tests (thermal performance, thermal cycle, thermal soak, ageing). (authors) 9 refs.

  2. Bent Core Liquid Crystal Polymers and Elastomers

    Science.gov (United States)

    Verduzco, Rafael; Hong, Seung Ho; Harden, John; Jakli, Antal; Sprunt, Sam; Gleeson, Jim

    2010-03-01

    Bent-core liquid crystals (LCs) have a kinked, or bent, molecular shape in contrast to the more common rod-like LCs. Due to their bent molecular shape, bent-core LCs form locally polar clusters, which result in novel LC phases and potentially useful properties such as ferroelectricity. Polymeric bent-core LCs are of particular interest because they can lead to new nanostructured soft materials with confined bent-core LCs. In this work, we investigate the synthesis, nanoscale structure, and physical properties of a variety of bent-core LCs and polymeric bent-core LCs. SAXS reveals the presence of polar clusters over a wide temperature range in the nematic phase for all materials studied, including bent-core side-group LC polymers and bent-core LC elastomers. The presence of locally polar clusters can account for the unexpected physical properties in nematic bent-core LCs, such as enhanced flexoelectricity. Direct flexoelectric measurements on pure bent-core LCs and swollen LCEs show that nematic bent-core materials have a flexoelectric coupling three orders orders of magnitude larger than calamitic LCs. Nematic clusters in bent-core LCs represent an unexpected and potentially useful phenomenon for building responsive LC devices.

  3. A thermoelectric generator using loop heat pipe and design match for maximum-power generation

    KAUST Repository

    Huang, Bin-Juine

    2015-09-05

    The present study focuses on the thermoelectric generator (TEG) using loop heat pipe (LHP) and design match for maximum-power generation. The TEG uses loop heat pipe, a passive cooling device, to dissipate heat without consuming power and free of noise. The experiments for a TEG with 4W rated power show that the LHP performs very well with overall thermal resistance 0.35 K W-1, from the cold side of TEG module to the ambient. The LHP is able to dissipate heat up to 110W and is maintenance free. The TEG design match for maximum-power generation, called “near maximum-power point operation (nMPPO)”, is studied to eliminate the MPPT (maximum-power point tracking controller). nMPPO is simply a system design which properly matches the output voltage of TEG with the battery. It is experimentally shown that TEG using design match for maximum-power generation (nMPPO) performs better than TEG with MPPT.

  4. Flow Accelerated Erosion-Corrosion (FAC) considerations for secondary side piping in the AP1000R nuclear power plant design

    International Nuclear Information System (INIS)

    Vanderhoff, J. F.; Rao, G. V.; Stein, A.

    2012-01-01

    The issue of Flow Accelerated Erosion-Corrosion (FAC) in power plant piping is a known phenomenon that has resulted in material replacements and plant accidents in operating power plants. Therefore, it is important for FAC resistance to be considered in the design of new nuclear power plants. This paper describes the design considerations related to FAC that were used to develop a safe and robust AP1000 R plant secondary side piping design. The primary FAC influencing factors include: - Fluid Temperature - Pipe Geometry/layout - Fluid Chemistry - Fluid Velocity - Pipe Material Composition - Moisture Content (in steam lines) Due to the unknowns related to the relative impact of the influencing factors and the complexities of the interactions between these factors, it is difficult to accurately predict the expected wear rate in a given piping segment in a new plant. This paper provides: - a description of FAC and the factors that influence the FAC degradation rate, - an assessment of the level of FAC resistance of AP1000 R secondary side system piping, - an explanation of options to increase FAC resistance and associated benefits/cost, - discussion of development of a tool for predicting FAC degradation rate in new nuclear power plants. (authors)

  5. Structural evaluation report of piping and support structure for design-changed hot-water layer system

    International Nuclear Information System (INIS)

    Ryu, Jeong Soo

    1998-05-01

    After hot-water layer system had been installed, the verification tests to reduce the radiation level at the top of reactor pool were performed many times. The major goal of this report is to assess the structural integrity on the piping and the support structures of design-changed hot-water layer system. The piping stress analysis was performed by using ADLPIPE program for the pump suction line and the pump discharge line subjected to dead weight, pressure, thermal expansion and seismic loadings. The stress analysis of the support structure was carried out using the reaction forces obtained from the piping stress analysis. The results of structural evaluation for the pipings and the support structures showed that the structural acceptance criteria were satisfied, in compliance with ASME, subsection ND for the piping and subsection NF for the support structures. Therefore based on the results of the analysis and the design, the structural integrity on the piping and the support structures of design-changed hot-water system was proved. (author). 9 refs., 9 tabs., 14 figs

  6. Research Activities on Development of Piping Design Methodology of High Temperature Reactors

    Energy Technology Data Exchange (ETDEWEB)

    Huh, Nam-Su [Seoul National Univ. of Science and Technology, Seoul(Korea, Republic of); Won, Min-Gu [Sungkyukwan Univ., Suwon (Korea, Republic of); Oh, Young-Jin [KEPCO Engineering and Construction Co. Inc., Gimcheon (Korea, Republic of); Lee, Hyeog-Yeon; Kim, Yoo-Gon [Korea Atomic Energy Research Institute, Daejeon(Korea, Republic of)

    2016-10-15

    A SFR is operated at high temperature and low pressure compared with commercial pressurized water reactor (PWR), and such an operating condition leads to time-dependent damages such as creep rupture, excessive creep deformation, creep-fatigue interaction and creep crack growth. Thus, high temperature design and structural integrity assessment methodology should be developed considering such failure mechanisms. In terms of design of mechanical components of SFR, ASME B and PV Code, Sec. III, Div. 5 and RCC-MRx provide high temperature design and assessment procedures for nuclear structural components operated at high temperature, and a Leak-Before-Break (LBB) assessment procedure for high temperature piping is also provided in RCC-MRx, A16. Three web-based evaluation programs based on the current high temperature codes were developed for structural components of high temperature reactors. Moreover, for the detailed LBB analyses of high temperature piping, new engineering methods for predicting creep C*-integral and creep COD rate based either on GE/EPRI or on reference stress concepts were proposed. Finally, the numerical methods based on Garofalo's model and RCC-MRx have been developed, and they have been implemented into ABAQUS. The predictions based on both models were compared with the experimental results, and it has been revealed that the predictions from Garafalo's model gave somewhat successful results to describe the deformation behavior of Gr. 91 at elevated temperatures.

  7. Piping Stress Analysis

    International Nuclear Information System (INIS)

    Setjo, Renaningsih

    2000-01-01

    Piping stress analysis on Primary Sampling System, Reactor Cooling System, and Feedwater System for AP600 have been performed. Piping stress analysis is one of the requirements in the design of piping system. Piping stress is occurred due to static and dynamic loads during service. Analysis was carried out. Using PS+CAEPIPE software based on the individual and combination loads with assumption that failure could be happened during normal, upset, emergency and faulted condition as describe in ASME III/ANSI B31.1. With performing the piping stress analysis, the layout (proper pipe routing) of the piping system can be design with the requirements of piping stress and pipe supports in mind I.e sufficient flexibility for thermal expansion, etc to commensurate with the i tended service such as temperatures, pressure, seismic and anticipated loading

  8. Design and demonstration of heat pipe cooling for NASP and evaluation of heating methods at high heating rates

    Energy Technology Data Exchange (ETDEWEB)

    Merrigan, M.A.; Sena, J.T.

    1989-01-01

    An evaluation of two heating methods for demonstration of NASP leading edge heat pipe technology was conducted. The heating methods were and rf induction heated plasma jet and direct rf induction. Tests were conducted to determine coupling from the argon plasma jet on a surface physically similar to a heat pipe. A molybdenum tipped calorimeter was fabricated and installed in an rf induction heated plasma jet for the test. The calorimetric measurements indicated a maximum power coupling of approximately 500 W/cm{sup 2} with the rf plasma jet. The effect of change in gas composition on the heating rate was investigated using helium. An alternative to the plasma heating of a heat pipe tip, an rf concentrator was evaluated for coupling to the hemispherical tip of a heat pipe. A refractory metal heat pipe was designed, fabricated, and tested for the evaluation. The heat pipe was designed for operation at 1400 to 1900 K with power input to 1000 W/cm{sup 2} over a hemispherical nose tip. Power input of 800 W/cm{sup 2} was demonstrated using the rf concentrator. 2 refs., 13 figs.

  9. Design Of A Laboratory Set-up For Evaluating Structural Strength Of Deteriorated Concrete Sewer Pipes

    NARCIS (Netherlands)

    Stanic, N.; Salet, T.; Langeveld, J.G.; Clemens, F.H.L.R.

    2014-01-01

    The principle of structural behaviour of buried concrete pipes is fairly understood, except for how material deterioration affects structural behaviour and performance. Consequently, information on the structural behaviour of deteriorated sewer pipes will contribute to better understanding of the

  10. On anti-earthquake design procedure of equipment and pipings in near future

    International Nuclear Information System (INIS)

    Shibata, H.

    1981-01-01

    The requirement of anti-earthquake design of nuclear power plants is getting severe year by year. The author will try to discuss how to control its severity and how to find a proper design procedure for licensing of new plants under such severe requirements. On the other hand we suffered from the enormous volumes of documents. To decrease such volumes, the format of documents should be standardized as well as the design procedure standardization. Starting from this point, we need the research and development on the following subjects: i) Standardization of design procedure. ii) Standardization of document. iii) Establishment of standard review procedure using computer. iv) Standardization of earthquake-resistant designed equipment. v) Standardization of anti-earthquake design procedure of piping systems. vi) Introducing margin evaluation procedure to design procedure. vii) Introducing proving test procedure of active component to design procedure. viii) Establishment of evaluation of human reliability in design, fabrication, inspection procedures. ix) Establishment of the proper relation of seismic trigger level and post-earthquake design procedures. (orig./HP)

  11. Alternative design of pipe sleeve for liquid removal mechanism in mortar slab layer

    Science.gov (United States)

    Nazri, W. M. H. Wan; Anting, N.; Lim, A. J. M. S.; Prasetijo, J.; Shahidan, S.; Din, M. F. Md; Anuar, M. A. Mohd

    2017-11-01

    Porosity is one of the mortar’s characteristics that can cause problems, especially in the room space that used high amount of water, such as bathrooms. Waterproofing is one of the technology that normally used to minimize this problem which is preventing deep penetration of liquid water or moisture into underlying concrete layers. However, without the proper mechanism to remove liquid water and moisture from mortar system, waterproofing layer tends to be damaged after a long period of time by the static formation of liquid water and moisture at mortar layer. Thus, a solution has been proposed to drain out water that penetrated into the mortar layer. This paper introduces a new solution using a Modified Pipe Sleeve (MPS) that installed at the mortar layer. The MPS has been designed considering the percentage surface area of the pipe sleeve that having contact with mortar layer (2%, 4%, 6%, 8% and 10%) with angle of holes of 60°. Infiltration test and flow rate test have been conducted to identify the effectiveness of the MPS in order to drain out liquid water or moisture from the mortar layer. In this study shows that, MPS surface area 10%, angled 60°, function effectively as a water removal compared to other design.

  12. Tentative design-philosophy for bellows in sodium cooled fast breeder reactors pipings

    International Nuclear Information System (INIS)

    Scaller, K.; Vrillon, B.

    1980-01-01

    Expansion joints have proved to be reliable components, when properly designed and realized, in normal industrial equipment. But nevertheless bellows have not been employed widely in nuclear reactors and almost not in sodium cooled fast breeder reactors, where use of expansion-joints could considerably shorten the length of pipelines and, in consequence, lower the cost of the power plant. In the framework of its research and development program on fast reactors the French Atomic Energy.Commission, in cooperation with the industry, develops guidelines, backed up by experiments, to allow a safe design of pipe-lines and compensating-devices. The main points of these guidelines are discussed in this paper with the understanding, that they are tentative rules subject to changes. The guidelines are a complement to existing rules, like ASME - Code III, Code Case 1481, standards of the EJMA Preliminary Draft for Code Case Class I, Expansion Joints in Piping systems and suppliers' rules for the special case of application to sodium cooled fast breeder reactors. Relatively small diameters and easily accessible expansion joints, on control rods and valves for example, are not concerned. These guidelines do not apply to the bellows which are used as an integral part of a component

  13. Bent Electro-Absorption Modulator

    DEFF Research Database (Denmark)

    2002-01-01

    components and the applied electric field in relation to the frequency of the modulated radiation, the bending losses (and possibly coupling losses) will provide extinction of light guided by the bent waveguide section. The refractive index contract may be modulated while keeping the absorption coefficient...... by bendng losses co-operates to provide more compact modulators with improved performance (extinction) and speed....

  14. Survey for optimum design of piping support system of nuclear power plant

    International Nuclear Information System (INIS)

    Tamura, Takakazu; Higashikubo, Katsuto

    1984-01-01

    In recent years, nuclear power plants are playing an important role in supply stably the country's electricity as generating capacity is being expanded. However, construction costs of the plant continue to skyrocket and the generating cost is losing its priority over the other power plant types. Such tendency requires us, plant manufacture, to strongly achieve our goal of constructing a more economical plant as well as realizing lower-cost energy without degrading quality of the plant. In response to this demand, we investigated the possibility of coming up with a more economical piping-support design for nuclear power plants, keeping in mind the realistic and practical design approach. Process and findings of this investigation are presented hereunder. (author)

  15. Design of a slug trap to assess the structural integrity of the pressurizer discharge piping system

    International Nuclear Information System (INIS)

    Geraets, L.H.; Weverbergh, J.

    1994-01-01

    The loads on the PWR pressurizer discharge piping and supports, due to a discharge event, consist of two parts: a ''transient'' effect due to the discharge of the water slug, and a ''quasi-steady-state'' effect due to the steam discharge. Tests performed after the TMI-2 accident have shown that the transient loads generated from the discharge of a cold, non-flashing slug could be an order of magnitude higher than the loads from an equivalent hot slug. Those large loads were not taken into account at the design stage of the Belgian plants, which resulted in an unresolved safety issue. This paper presents the original solution that has been developed for the determination of the slug motion, together with the required accompanying hardware measures; those measures include the design and implementation of a ''slug trap'', in order to divert the water slug from the main discharge line, when the loads cannot be afforded

  16. New design solutions for low-power energy production in water pipe systems

    Directory of Open Access Journals (Sweden)

    Helena M. Ramos

    2009-12-01

    Full Text Available This study is the result of ongoing research for a European Union 7th Framework Program Project regarding energy converters for very low heads, and aims to analyze optimization of new cost-effective hydraulic turbine designs for possible implementation in water supply systems (WSSs or in other pressurized water pipe infrastructures, such as irrigation, wastewater, or drainage systems. A new methodology is presented based on a theoretical, technical and economic analysis. Viability studies focused on small power values for different pipe systems were investigated. Detailed analyses of alternative typical volumetric energy converters were conducted on the basis of mathematical and physical fundamentals as well as computational fluid dynamics (CFD associated with the interaction between the flow conditions and the system operation. Important constraints (e.g., size, stability, efficiency, and continuous steady flow conditions can be identified and a search for alternative rotary volumetric converters is being conducted. As promising cost-effective solutions for the coming years, adapted rotor-dynamic turbomachines and non-conventional axial propeller devices were analyzed based on the basic principles of pumps operating as turbines, as well as through an extensive comparison between simulations and experimental tests.

  17. Design, manufacturing and testing of a portable vaccine carrier box employing thermoelectric module and heat pipe.

    Science.gov (United States)

    Putra, N

    2009-01-01

    Vaccination is a highly effective method and a cheap tool for preventing certain infectious diseases. Routine immunization programs protect most of the world's children from diseases that claim millions of lives each year. There are many practical problems impeding vaccine delivery, especially to maintain the cold chain system, which is the means for storing and transporting vaccines in a potent state from the manufacturer to the person being immunized at a temperature of 2-8 degrees C. The development of the solid state thermoelectric cooling system has permitted newly developed packages that are capable of meeting many requirements and applications where environmental concern, size, weight, performance and noise are an issue. This paper describes the development of a vaccine carrier box. A combination of a thermoelectric module and a heat pipe is used for the cooling system. The position of the heat pipe as a heat sink on the hot side of the thermoelectric module will enhance the thermoelectric performance. The minimum temperature in the cabin of the vaccine carrier box reached -10 degrees C, which indicates that the design of the vaccine carrier box can maintain the vaccine at desired temperatures.

  18. Development of an evaluation method for seismic isolation systems of nuclear power facilities. Seismic design analysis methods for crossover piping system

    International Nuclear Information System (INIS)

    Tai, Koichi; Sasajima, Keisuke; Fukushima, Shunsuke; Takamura, Noriyuki; Onishi, Shigenobu

    2014-01-01

    This paper provides seismic design analysis methods suitable for crossover piping system, which connects between seismic isolated building and non-isolated building in the seismic isolated nuclear power plant. Through the numerical study focused on the main steam crossover piping system, seismic response spectrum analysis applying ISM (Independent Support Motion) method with SRSS combination or CCFS (Cross-oscillator, Cross-Floor response Spectrum) method has found to be quite effective for the seismic design of multiply supported crossover piping system. (author)

  19. Load reduction in piping design by optimizing dynamic flow behavior at operational and fault conditions

    International Nuclear Information System (INIS)

    Tilman Diesselhorst; Werner Schnellhammer

    2005-01-01

    Full text of publication follows: Piping and supports have to be designed to withstand the loading from fluid dynamic load cases like turbine trip and pump trip or even the loading resulting from pipe break. Especially as these dynamic loads have to be superimposed to the static loads from gravity and thermal expansion, there is a great interest to minimize the dynamic loads as far as possible. Usually the fluid dynamic forces are created by pressure surges which are caused by rapid changes of the flow conditions. These changes are mainly effected by valve actuation in the systems. Therefore minimizing dynamic loads means to optimize the functions of valves and check valves and to adapt it to the system behavior for example during pump trip. So it was the objective to prepare the pressure surge program for the fluid dynamic load cases in a way that it was possible to carry out the optimization procedure in the course of calculating the design loads from the prescribed load cases. Primarily the pressure surges propagating through the piping system are generated by opening or closing of valves, but in the most cases the transient flow behavior again has an effect on the valve behavior, especially with check valves and hydraulically actuated valves. That means the valve behavior has to be modeled together with the piping system and the remaining components necessary like pumps. Therefore detailed models were developed and installed in the pressure surge program to describe the different valve functions for steam systems and check valves and disk check valves in water systems. In these models the characteristic data of valve movement and damping behavior can be varied to find the optimized function for the load case. On the other hand criteria were found and developed which guarantee optimized valve functions in order to create small pressure surges. In some cases even small modifications of the damping device have a strong effect on reducing the fluid forces. In the

  20. Ion implantation for manufacturing bent and periodically bent crystals

    Energy Technology Data Exchange (ETDEWEB)

    Bellucci, Valerio; Camattari, Riccardo; Guidi, Vincenzo, E-mail: guidi@fe.infn.it; Mazzolari, Andrea; Paternò, Gianfranco [Department of Physics and Earth Sciences, University of Ferrara, Via Saragat 1/c, 44122 Ferrara, Italy and INFN, Section of Ferrara (Italy); Mattei, Giovanni, E-mail: giovanni.mattei@unipd.it; Scian, Carlo [Department of Physics and Astronomy Galileo Galilei, University of Padova, Via Marzolo 8, 35131 Padova (Italy); Lanzoni, Luca [Dipertimento di Economia e Tecnologia, Università degli Studi della Repubblica di San Marino, Salita alla Rocca, 44, 47890 San Marino Città (San Marino)

    2015-08-10

    Ion implantation is proposed to produce self-standing bent monocrystals. A Si sample 0.2 mm thick was bent to a radius of curvature of 10.5 m. The sample curvature was characterized by interferometric measurements; the crystalline quality of the bulk was tested by X-ray diffraction in transmission geometry through synchrotron light at ESRF (Grenoble, France). Dislocations induced by ion implantation affect only a very superficial layer of the sample, namely, the damaged region is confined in a layer 1 μm thick. Finally, an elective application of a deformed crystal through ion implantation is here proposed, i.e., the realization of a crystalline undulator to produce X-ray beams.

  1. Ocean thermal energy conversion cold water pipe preliminary design project. Task 2. Analysis for concept selection

    Energy Technology Data Exchange (ETDEWEB)

    None

    1979-04-01

    The successful performance of the CWP is of crucial importance to the overall OTEC system; the pipe itself is considered the most critical part of the entire operation. Because of the importance the CWP, a project for the analysis and design of CWP's was begun in the fall of 1978. The goals of this project were to study a variety of concepts for delivering cold water to an OTEC plant, to analyze and rank these concepts based on their relative cost and risk, and to develop preliminary design for those concepts which seemed most promising. Two representative platforms and sites were chosen: a spar buoy of a Gibbs and Cox design to be moored at a site off Punta Tuna, Puerto Rico, and a barge designed by APL/Johns Hopkins University, grazing about a site approximately 200 miles east of the coast of Brazil. The approach was to concentrate on the most promising concepts and on those which were either of general interest or espoused by others (e.g., steel and concrete concepts). Much of the overall attention, therefore, focused on analyzing rigid and compliant wall design, while stockade (except for the special case of the FRP stockade) and bottom-mounted concepts received less attention. A total of 67 CWP concepts were initially generated and subjected to a screening process. Of these, 16 were carried through design analysis, costing, and ranking. Study results are presented in detail. (WHK)

  2. Design and construction of an in-pipe robot for inspection and maintenance

    KAUST Repository

    Sibai, Fadi N.

    2012-12-01

    Inspection and maintenance of aging pipelines is crucial to the reliable and continued distribution of hydrocarbons. In this paper, we describe the design and construction of a robotic platform for inspection and minor maintenance of pipelines. The 7.5 kg robotic platform was demonstrated to move straight inside 12″ to 16″ diameter pipes in a forward or backward direction, and either horizontally or vertically. The experimental robotic platform has three sets of two wheels, and three driving motors. The equations governing the mechanical frame\\'s component sizes are presented and the robotic frame component dimensions derived. The paper also discusses the construction and testing of the robot. Future work includes adding sensors, controls for turning, a microcontroller board, and a robotic arm for performing maintenance tasks. © 2012 IEEE.

  3. Electrical design of a 110-ft long muon pipe with automatic degaussing

    International Nuclear Information System (INIS)

    Visser, A.T.

    1985-11-01

    This memo describes a magnetized cylindrical pipe made from tape wound grain oriented low carbon steel rolls. Grain oriented steel yields much higher magnetic fields at low ampereturns than cast iron or other steel pipes. This is especially important when only a few windings are allowed in the inner bore. The power supply and operating cost are also much lower. The pipe has a high (approx.9 kG) remnant field, but is automatically degaussed upon shutdown of the DC excitation power supply. A remnant field detector senses whether degaussing was successful. The pipe is used in the muon beam line. Its magnetic field deflects unwanted halo muons. Tests need to be conducted with and without pipe field. It is therefore desirable that the pipe field automatically returns to zero when the DC excitation is shut off. This can be rather easily accomplished

  4. Assessment of value-impact associated with the elimination of postulated pipe ruptures from the design basis for nuclear power plants

    International Nuclear Information System (INIS)

    Holman, G.S.; Chou, C.K.

    1985-01-01

    The US Nuclear Regulatory Commission is proposing to amend the regulations that currently require that the design basis for nuclear power plants include the postulation of dynamic effects from loss of coolant accidents up to and including the double-ended rupture of the largest pipe in the reactor coolant system. Proposed modifications would allow analyses to serve as a sufficient basis for excluding dynamic effects, including but not necessarily limited to pipe whip and jet impingement, associated with specific pipe ruptures. Only dynamic effects would be impacted; current design requirements for containment sizing and discharge capacity of emergency core cooling systems would remain unchanged. This report presents a detailed analysis of value-impact associated with the proposed amendment for PWR reactor coolant loop piping and for BWR recirculation loop piping. The effect of extending application of the proposed rule change to other piping systems is also assessed in a less quantitative manner

  5. Bent Flyvbjerg: Power and project management, an appreciation

    NARCIS (Netherlands)

    Clegg, S.R.

    2008-01-01

    Purpose – The purpose of this paper is to provide a critique of Bent Flyybjerg's work that has high relevance to the project management (PM) literature. Design/methodology/approach – The paper takes the form of a narrative with argument and analysis. Findings – The paper challenges readers, PM

  6. Bent Solenoids with Superimposed Dipole Fields

    Energy Technology Data Exchange (ETDEWEB)

    Meinke, Rainer, B.; Goodzeit, Carl, L.

    2000-03-21

    A conceptual design and manufacturing technique were developed for a superconducting bent solenoid magnet with a superimposed dipole field that would be used as a dispersion device in the cooling channel of a future Muon Collider. The considered bent solenoid is equivalent to a 180° section of a toroid with a major radius of ~610 mm and a coil aperture of ~416 mm. The required field components of this magnet are 4 tesla for the solenoid field and 1 tesla for the superimposed dipole field. A magnet of this size and shape, operating at these field levels, has to sustain large Lorentz forces resulting in a maximum magnetic pressure of about 2,000 psi. A flexible round mini-cable with 37 strands of Cu-NbTi was selected as the superconductor. Detailed magnetic analysis showed that it is possible to obtain the required superimposed dipole field by tilting the winding planes of the solenoid by ~25°. A complete structural analysis of the coil support system and the helium containment vessel under thermal, pressure, and Lorentz force loads was carried out using 3D finite element models of the structures. The main technical issues were studied and solutions were worked out so that a highly reliable magnet of this type can be produced at an affordable cost.

  7. A SYNTHESIS METHOD OF BASIC TERNARY BENT-SQUARES BASED ON THE TRIAD SHIFT OPERATOR

    Directory of Open Access Journals (Sweden)

    O. N. Zhdanov

    2017-01-01

    Full Text Available Practical application of advanced algebraic constructions in modern communication systems based on MC-CDMA (Multi Code Code Division Multiple Access technology and in cryptography necessitates their further research. One of the most commonly used advanced algebraic construction is the binary bent-function having a uniform amplitude spectrum of the Walsh-Hadamard transform and, accordingly, having the maximal distance from the codewords of affine code. In addition to the binary bent-functions researchers are currently focuses on the development of synthesis methods of their many-valued analogues. In particular, one of the most effective methods for the synthesis of many-valued bent-functions is the method based on the Agievich bent-squares. In this paper, we developed a regular synthesis method of the ternary bent-squares on the basis of an arbitrary spectral vector and the regular operator of the triad shift. The classification of spectral vectors of lengths N = 3 and N = 9 is performed. On the basis of spectral classification more precise definition of many-valued bent-sequences is given, taking into account the existence of the phenomenon of many-valued bent-sequences for the length, determined by odd power of base. The paper results are valuable for practical use: the development of new constant amplitude codes for MC-CDMA technology, cryptographic primitives, data compression algorithms, signal structures, algorithms of block and stream encryption, based on advanced principles of many-valued logic. The developed bent-squares design method is also a basis for further theoretical research: development of methods of the permutation of rows and columns of basic bent-squares and their sign coding, synthesis of composite bent-squares. In addition, the data on the spectral classification of vectors give the task of constructing the synthesis methods of bent-functions of lengths N = 32k+1, k Є ℕ.

  8. Computational simulations of frictional losses in pipe networks confirmed in experimental apparatusses designed by honors students

    Science.gov (United States)

    Pohlman, Nicholas A.; Hynes, Eric; Kutz, April

    2015-11-01

    Lectures in introductory fluid mechanics at NIU are a combination of students with standard enrollment and students seeking honors credit for an enriching experience. Most honors students dread the additional homework problems or an extra paper assigned by the instructor. During the past three years, honors students of my class have instead collaborated to design wet-lab experiments for their peers to predict variable volume flow rates of open reservoirs driven by gravity. Rather than learn extra, the honors students learn the Bernoulli head-loss equation earlier to design appropriate systems for an experimental wet lab. Prior designs incorporated minor loss features such as sudden contraction or multiple unions and valves. The honors students from Spring 2015 expanded the repertoire of available options by developing large scale set-ups with multiple pipe networks that could be combined together to test the flexibility of the student team's computational programs. The engagement of bridging the theory with practice was appreciated by all of the students such that multiple teams were able to predict performance within 4% accuracy. The challenges, schedules, and cost estimates of incorporating the experimental lab into an introductory fluid mechanics course will be reported.

  9. A structural design and analysis of a piping system including seismic load

    International Nuclear Information System (INIS)

    Hsieh, B.J.; Kot, C.A.

    1991-01-01

    The structural design/analysis of a piping system at a nuclear fuel facility is used to investigate some aspects of current design procedures. Specifically the effect of using various stress measures including ASME Boiler ampersand Pressure Vessel (B ampersand PV) Code formulas is evaluated. It is found that large differences in local maximum stress values may be calculated depending on the stress criterion used. However, when the global stress maximum for the entire system are compared the differences are much smaller, being nevertheless, for some load combinations, of the order of 50 percent. The effect of using an Equivalent Static Method (ESM) analysis is also evaluated by comparing its results with those obtained from a Response Spectrum Method (RSM) analysis with the modal responses combined by using the absolute summation (ABS), by using the square root of the squares (SRSS), and by using the 10 percent method (10PC). It is shown that for a spectrum amplification factor (equivalent static coefficient greater than unity) of at least 1.32 must be used in the current application of the ESM analysis in order to obtain results which are conservative in all aspects relative to an RSM analysis based on ABS. However, it appears that an adequate design would be obtained from the ESM approach even without the use of a spectrum amplification factor. 7 refs., 3 figs., 3 tabs

  10. Observations on the structural design and analysis of a piping system

    International Nuclear Information System (INIS)

    Hsieh, B.J.; Kot, C.A.

    1991-01-01

    The structural design/analysis of a gas exhaust system at a nuclear fuel facility is used to investigate some aspects of current piping design procedures. Specifically the effect of using various stress measures including ASME Boiler ampersand Pressure Vessel (B ampersand PV) Code formulas is evaluated. It is found that large differences in local maximum stress values may be calculated depending on the stress criterion used. However, when the global stress maxima for the entire system are compared the differences are much smaller, being nevertheless, for some load combinations, of the order of 50 percent. The effect of using an equivalent static method (ESM) analysis is also evaluated by comparing its results with those obtained from a response spectrum method (RSM) analysis. It is shown that a spectrum amplification factor (equivalent static coefficient greater than unity) of at least 1.32 must be used in the current application of the ESM analysis in order to obtain results which are conservative in all aspects relative to the RMS analysis. However, it appears that an adequate design would be obtained from the ESM approach even without the use of a spectrum amplification factor. 7 refs., 4 figs., 7 tabs

  11. Whistling of pipes with narrow corrugations: scale model tests and consequences for carcass design

    NARCIS (Netherlands)

    Golliard, J.; Belfroid, S.P.C.; Bendiksen, E.; Frimodt, C.

    2013-01-01

    Pipes for gas production and transport with a corrugated inner surface, as used in flexible pipes, can be subject to Flow-Induced Pulsations when the flow velocity is larger than a certain velocity. This onset velocity is dependent on the geometry of the corrugations, the operational conditions and

  12. Design and testing of a heat pipe gas combustion system for the STM4-120 Stirling engine

    Science.gov (United States)

    Khalili, K.; Godett, T. M.; Meijer, R. J.; Verhey, R. P.

    Evaporators of a novel geometry, designed to have a more compact size yet the same output as larger, conventional heat pipes, have been fabricated and tested. A technique was developed to calculate capillary pressure required inside the heat pipe. Several quarter- and full-scale evaporators were designed and successfully tested. The burner, film-cooled combustion chamber, and preheater were designed and tested separately. A complete heat pipe gas combustion system (HPGC) was tested, showing an efficiency of 89 percent was measured at 20 kWth. A film-cooled combustion chamber was tested with flame temperatures of 2200 C and wall temperatures below 1000 C using preheated air for film cooling. Also, a full-scale HPGC was tested at an excess of 95 kWth, showing efficiency in the range of 85 to 90 percent under steady-state conditions. Results of transient and startup tests, carried out to evaluate the performance of the heat pipe, all also reported.

  13. Application of bounding spectra to seismic design of piping based on the performance of above ground piping in power plants subjected to strong motion earthquakes

    Energy Technology Data Exchange (ETDEWEB)

    Stevenson, J.D. [Stevenson and Associates, Cleveland, OH (United States)

    1995-02-01

    This report extends the potential application of Bounding Spectra evaluation procedures, developed as part of the A-46 Unresolved Safety Issue applicable to seismic verification of in-situ electrical and mechanical equipment, to in-situ safety related piping in nuclear power plants. The report presents a summary of earthquake experience data which define the behavior of typical U.S. power plant piping subject to strong motion earthquakes. The report defines those piping system caveats which would assure the seismic adequacy of the piping systems which meet those caveats and whose seismic demand are within the bounding spectra input. Based on the observed behavior of piping in strong motion earthquakes, the report describes the capabilities of the piping system to carry seismic loads as a function of the type of connection (i.e. threaded versus welded). This report also discusses in some detail the basic causes and mechanisms for earthquake damages and failures to power plant piping systems.

  14. Application of bounding spectra to seismic design of piping based on the performance of above ground piping in power plants subjected to strong motion earthquakes

    International Nuclear Information System (INIS)

    Stevenson, J.D.

    1995-02-01

    This report extends the potential application of Bounding Spectra evaluation procedures, developed as part of the A-46 Unresolved Safety Issue applicable to seismic verification of in-situ electrical and mechanical equipment, to in-situ safety related piping in nuclear power plants. The report presents a summary of earthquake experience data which define the behavior of typical U.S. power plant piping subject to strong motion earthquakes. The report defines those piping system caveats which would assure the seismic adequacy of the piping systems which meet those caveats and whose seismic demand are within the bounding spectra input. Based on the observed behavior of piping in strong motion earthquakes, the report describes the capabilities of the piping system to carry seismic loads as a function of the type of connection (i.e. threaded versus welded). This report also discusses in some detail the basic causes and mechanisms for earthquake damages and failures to power plant piping systems

  15. On bent and semi-bent quadratic Boolean functions

    DEFF Research Database (Denmark)

    Charpin, P.; Pasalic, Enes; Tavernier, C.

    2005-01-01

    The maximum-length sequences, also called m-sequences, have received a lot of attention since the late 1960s. In terms of linear-feedback shift register (LFSR) synthesis they are usually generated by certain power polynomials over a finite field and in addition are characterized by a low cross...... their results to even n. We further investigate the conditions on the choice of ci for explicit definitions of new infinite families having three and four trace terms. Also, a class of nonpermutation polynomials whose composition with a quadratic function yields again a quadratic semi-bent function is specified...

  16. Flexible ultrasonic pipe inspection apparatus

    Energy Technology Data Exchange (ETDEWEB)

    Jenkins, C.F.; Howard, B.D.

    1994-01-01

    Pipe crawlers, pipe inspection {open_quotes}rabbits{close_quotes} and similar vehicles are widely used for inspecting the interior surfaces of piping systems, storage tanks and process vessels for damaged or flawed structural features. This paper describes the design of a flexible, modular ultrasonic pipe inspection apparatus.

  17. Bent functions results and applications to cryptography

    CERN Document Server

    Tokareva, Natalia

    2015-01-01

    Bent Functions: Results and Applications to Cryptography offers a unique survey of the objects of discrete mathematics known as Boolean bent functions. As these maximal, nonlinear Boolean functions and their generalizations have many theoretical and practical applications in combinatorics, coding theory, and cryptography, the text provides a detailed survey of their main results, presenting a systematic overview of their generalizations and applications, and considering open problems in classification and systematization of bent functions. The text is appropriate for novices and advanced

  18. Design rules for piping: plastic stability of straight parts under level d loadings

    International Nuclear Information System (INIS)

    Touboul, F.; Ben Jdidia, M.; Acker, D.

    1989-01-01

    For piping systems, design rules for straight parts, under static loads are based on limit analysis. We have studied the accuracy of such method when different geometries and combinations of loadings are concerned. Analysing theoretical computations, we have pointed out the hypothesis inherent to the formulation used in design codes (ASME, RCCM, RCC-MR). We have determined a formula closer to the theoretical results that we have compared to experiments. We have interpreted up to 170 tests from different laboratories with varied geometries (D/e from 10 to 115) and manifold type of loadings, with or without pressure: pure bending, pure torsion, bending with torsion, combined bending. We have applied the codes rules and we have noticed that for certain tests, experimental ultimate moments were fourty per cent lower than the coded one. As geometry is concerned, contrary to the limit analysis prediction, ultimate load does not depend only on the modulus of inertia (Z) but also on the D/e ratio by a (D/e) .33 coefficient. As level D service limits were considered, we have taken out the maximal load borne by the tubes. To ensure the conservatism of the rule, the allowable stress for austenitic steels, as defined by codes, must be taken at the value defined by ASME, Section III, Appendix F (criteria for component, F 1331)

  19. Design of a micro-robot with an electro-pneumatic servo-actuator for the intra-pipe inspection

    International Nuclear Information System (INIS)

    Anthierens, C.

    1999-12-01

    Micro Electro Mechanical Systems (MEMS) are integrated in many current products and are not only the concern of military defence or medicine. Nowadays micro actuators are diversified by using different kind of energy, and creating different motions. Several applications require small systems to inspect confined and hostile places. Vapour generators in nuclear plants are composed with 3000 to 5000 vertical pipes of 17 mm diameter. These pipes endure high mechanical constraints and have to be inspected to detect eventual cracks. Our study is based on the design, modelling and implementation of a micro-robot enable to move up and carry sensors in these pipes. It moves as an inchworm and then is composed by 2 blocking modules that brace the robot on the pipe sides, and one stretching module that creates a step. This actuator is pneumatic and composed by metal bellows. By this original design, the micro-robot have a good power to volume ratio and thus it can carry a load higher than 1 kg. Its good positioning accuracy is proved with a 90 mm course where the error of positioning is less than 60μm. A PID control law is used to control the robot but state feed back control law is planed. (author)

  20. Bent-Pipe Vs On-Board Processing

    Indian Academy of Sciences (India)

    Multi-beam frequency re-use which increases satellite raw capacity;; Empty uplink time slots to be discarded, increasing the efficiency of downlink transmission;; Dynamic reallocation of unused bandwidth;; Asymmetric Uplink and down link bandwidth to take advantage of traffic statistics;; Statistical multiplexing which ...

  1. Examination of the CLIC drive beam pipe design for thermal distortion caused by distributed beam loss

    CERN Document Server

    Johnson, C D

    1997-01-01

    Beam transport programs are widely used to estimate the distribution of power deposited in accelerator structures by particle beams, either intentionally as for targets or beam dumps or accidentally owing to beam loss incidents. While this is usually adequate for considerations of radiation safety, it does not reveal the expected temperature rise and its effect on structural integrity. To find this, thermal diffusion must be taken into account, requiring another step in the analysis. The method that has been proposed is to use the output of a transport program, perhaps modified, as input for a finite element analysis program that can solve the thermal diffusion equation. At CERN, the design of the CLIC drive beam pipe has been treated in this fashion. The power distribution produced in the walls by a distributed beam loss was found using the electron gamma shower code EGS4. The distribution of power density was then used to form the input for the finite element analysis program ANSYS, which was able to find t...

  2. Cardiorespiratory and metabolic responses during straight and bent knee cycling.

    Science.gov (United States)

    Mandroukas, K; Angelopoulou, N; Christoulas, K; Vrabas, I S

    2000-06-01

    This study examined the influence of knee angle on the cardiorespiratory system loading during submaximal and maximal stationary cycle ergometry. Experimental design and participants: eighteen untrained women (age: 21+/-1.88 years, weight: 57+/-5.75 kg, height: 165+/-5.03 cm, values are mean+/-SD) volunteered as subjects and underwent two-cycle ergometer incremental (Jaeger ER900) tests: 1) straight knee (180 degrees), 2) bent knee (140 degrees). oxygen uptake (VO2), ventilation (VE) and respiratory exchange ratio (RER) were measured continuously during each test using an open circuit spirometry and blood lactate concentration was determined by means of an enzymatic method. Comparing cycling with "straight knee" to cycling with "bent knee" at 50 W, heart rate (HR), V(E) and VO2 were significantly higher (10.6%, 12.5%, 17.8%). At 100 W, blood lactate was significantly lower (10.8%) while VO2 and RER was higher (5.5%, 7.1%). During maximal exercise, the total exercise time was significantly longer (11.2%) and VE, VO2 and HR were significantly higher during cycling with "straight knee" compared to cycling with "bent knee". No significant difference in peak lactate was evident between the two sitting positions. The results of this study indicate that cycling with bent knee requires lower oxygen uptake while pedaling with straight knee is the only way to reach VO2max during cycle testing, since the cardiorespiratory system is fully taxed.

  3. Integrated source and channel encoded digital communication system design study

    Science.gov (United States)

    Alem, W. K.; Huth, G. K.; Simon, M. K.

    1978-01-01

    The particular Ku-band carrier, PN despreading, and symbol synchronization strategies, which were selected for implementation in the Ku-band transponder aboard the orbiter, were assessed and evaluated from a systems performance viewpoint, verifying that system specifications were met. A study was performed of the design and implementation of tracking techniques which are suitable for incorporation into the Orbiter Ku-band communication system. Emphasis was placed on maximizing tracking accuracy and communication system flexibility while minimizing cost, weight, and system complexity of Orbiter and ground systems hardware. The payload communication study assessed the design and performance of the forward link and return link bent-pipe relay modes for attached and detached payloads. As part of this study, a design for a forward link bent-pipe was proposed which employs a residual carrier but which is tracked by the existing Costas loop.

  4. Optimization of Wellhead Piping Design for Production Wells at Development of Steam-Water Geothermal Fields

    Directory of Open Access Journals (Sweden)

    A.N. Shulyupin

    2017-03-01

    Full Text Available At present, the exploitation of geothermal resources develops in a fair competition with other types of energy resources. This leads to actuality of questions which associated with the more efficient use of existing wells, because cost of their drilling is a significant share of geothermal projects. In domestic practice of development of geothermal resources the steam-water wells have greatest energy potential. One way to improve the performance of these wells is a providing of smooth change of direction of motion of steam-water mixture from the vertical, in the well, to the horizontal, in steam gathering system. Typical wellhead piping of domestic steam-water wells involves the removal of the mixture through a cross bar at a right angle. Cross bar can generate considerable pressure loss that increases the operating pressure at the mouth of the well and reduces flow rate. It seems reasonable to substitute the typical cross bar by smooth pipe bend. This reduces wellhead resistance coefficient by more than on 2. Increase of curvature radius of pipe bend reduces the pressure loss to a local resistance but increases the friction pressure loss. There is an optimal curvature radius of pipe bend for minimum pressure loss in view of a local resistance and friction in the pipe bend. Calculations have shown that the optimum value for the radius of curvature is found in the range from 1.4 to 4.5 tube internal diameters. However, for technological reasons it is recommended to choose the radius of curvature from 1.4 to 2.4 diameters. Mounting of smooth pipe bend on the wellhead can provide significant economic benefits. For Mutnovka field (Kamchatka, this effect is estimated at 17.5 million rubles in year.

  5. Effects of design variables predicted by a steady - state thermal performance analysis model of a loop heat pipe

    International Nuclear Information System (INIS)

    Jung, Eui Guk; Boo, Joon Hong

    2008-01-01

    This study deals with a mathematical modeling for the steady-state temperature characteristics of an entire loop heat pipe. The lumped layer model was applied to each node for temperature analysis. The flat type evaporator and condenser in the model had planar dimensions of 40 mm (W) x 50 mm (L). The wick material was a sintered metal and the working fluid was methanol. The molecular kinetic theory was employed to model the phase change phenomena in the evaporator and the condenser. Liquid-vapor interface configuration was expressed by the thin film theories available in the literature. Effects of design factors of loop heat pipe on the thermal performance were investigated by the modeling proposed in this study

  6. 49 CFR 192.112 - Additional design requirements for steel pipe using alternative maximum allowable operating...

    Science.gov (United States)

    2010-10-01

    ..., DEPARTMENT OF TRANSPORTATION (CONTINUED) PIPELINE SAFETY TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE..., fully killed, continuously cast steel with calcium treatment. (2) The carbon equivalents of the steel... anomalies during construction, strength testing and anticipated operational stresses. (4) The pipe must be...

  7. Qualification of new design of flexible pipe against singing: testing at multiple scales

    NARCIS (Netherlands)

    Golliard, J.; Lunde, K.; Vijlbrief, O.

    2016-01-01

    Flexible pipes for production of oil and gas typically present a corrugated inner surface. This has been identified as the cause of "singing risers": Flow-Induced Pulsations due to the interaction of sound waves with the shear layers at the small cavities present at each of the multiple

  8. A Designer Fluid For Aluminum Phase Change Devices. Performance Enhancement in Copper Heat Pipes Performance Enhancement in Copper Heat Pipes. Volume 3

    Science.gov (United States)

    2016-11-17

    and the curvature varies with the height of the liquid meniscus. In the present work, the corner flow existed over a very short length. 93 Approved...to gradual changes in meniscus height whereas a pinned meniscus in an open groove varies curvature with contact angle. 114 Approved for public...region was calculated to be less than 2% of the total length for Wick #2. Flow Regions in a Grooved Heat Pipe The liquid flow in the heat pipe varies

  9. Bent and bent(4) spectra of Boolean functions over finite fields

    DEFF Research Database (Denmark)

    Anbar Meidl, Nurdagül; Meidl, Wilfried

    2017-01-01

    to the conventional Walsh transform, and hence a 0-bent4 function is bent. In this article we generalize the concept of partially bent functions to the transforms V-f(c). We show that every quadratic function is partially bent, and hence it is plateaued with respect to any of the transforms V-f(c). In detail we...... analyse two quadratic monomials. The first has values as small as possible in its spectra with respect to all transforms V-f(c), and the second has a flat spectrum for a large number of c. Moreover, we show that every quadratic function is c-bent4 for at least three distinct c. In the last part we analyse...... a cubic monomial. We show that it is c-bent(4) only for c = 1, the function is then called negabent, which shows that non-quadratic functions exhibit a different behaviour. (C) 2017 Elsevier Inc. All rights reserved....

  10. Introduction to Heat Pipes

    Science.gov (United States)

    Ku, Jentung

    2015-01-01

    This is the presentation file for the short course Introduction to Heat Pipes, to be conducted at the 2015 Thermal Fluids and Analysis Workshop, August 3-7, 2015, Silver Spring, Maryland. NCTS 21070-15. Course Description: This course will present operating principles of the heat pipe with emphases on the underlying physical processes and requirements of pressure and energy balance. Performance characterizations and design considerations of the heat pipe will be highlighted. Guidelines for thermal engineers in the selection of heat pipes as part of the spacecraft thermal control system, testing methodology, and analytical modeling will also be discussed.

  11. Behavior of micropiles in bridge bent applications.

    Science.gov (United States)

    2010-12-01

    This project concerned the behavior of micropiles under lateral loads. The North Carolina Department of Transportation was specifically interested in the use of micropiles to support bridge bents. In this configuration micropiles would be subjected t...

  12. An Eddy Current Testing Platform System for Pipe Defect Inspection Based on an Optimized Eddy Current Technique Probe Design

    Directory of Open Access Journals (Sweden)

    Damhuji Rifai

    2017-03-01

    Full Text Available The use of the eddy current technique (ECT for the non-destructive testing of conducting materials has become increasingly important in the past few years. The use of the non-destructive ECT plays a key role in the ensuring the safety and integrity of the large industrial structures such as oil and gas pipelines. This paper introduce a novel ECT probe design integrated with the distributed ECT inspection system (DSECT use for crack inspection on inner ferromagnetic pipes. The system consists of an array of giant magneto-resistive (GMR sensors, a pneumatic system, a rotating magnetic field excitation source and a host PC acting as the data analysis center. Probe design parameters, namely probe diameter, an excitation coil and the number of GMR sensors in the array sensor is optimized using numerical optimization based on the desirability approach. The main benefits of DSECT can be seen in terms of its modularity and flexibility for the use of different types of magnetic transducers/sensors, and signals of a different nature with either digital or analog outputs, making it suited for the ECT probe design using an array of GMR magnetic sensors. A real-time application of the DSECT distributed system for ECT inspection can be exploited for the inspection of 70 mm carbon steel pipe. In order to predict the axial and circumference defect detection, a mathematical model is developed based on the technique known as response surface methodology (RSM. The inspection results of a carbon steel pipe sample with artificial defects indicate that the system design is highly efficient.

  13. An Eddy Current Testing Platform System for Pipe Defect Inspection Based on an Optimized Eddy Current Technique Probe Design

    Science.gov (United States)

    Rifai, Damhuji; Abdalla, Ahmed N.; Razali, Ramdan; Ali, Kharudin; Faraj, Moneer A.

    2017-01-01

    The use of the eddy current technique (ECT) for the non-destructive testing of conducting materials has become increasingly important in the past few years. The use of the non-destructive ECT plays a key role in the ensuring the safety and integrity of the large industrial structures such as oil and gas pipelines. This paper introduce a novel ECT probe design integrated with the distributed ECT inspection system (DSECT) use for crack inspection on inner ferromagnetic pipes. The system consists of an array of giant magneto-resistive (GMR) sensors, a pneumatic system, a rotating magnetic field excitation source and a host PC acting as the data analysis center. Probe design parameters, namely probe diameter, an excitation coil and the number of GMR sensors in the array sensor is optimized using numerical optimization based on the desirability approach. The main benefits of DSECT can be seen in terms of its modularity and flexibility for the use of different types of magnetic transducers/sensors, and signals of a different nature with either digital or analog outputs, making it suited for the ECT probe design using an array of GMR magnetic sensors. A real-time application of the DSECT distributed system for ECT inspection can be exploited for the inspection of 70 mm carbon steel pipe. In order to predict the axial and circumference defect detection, a mathematical model is developed based on the technique known as response surface methodology (RSM). The inspection results of a carbon steel pipe sample with artificial defects indicate that the system design is highly efficient. PMID:28335399

  14. Heat pipes

    CERN Document Server

    Dunn, Peter D

    1982-01-01

    A comprehensive, up-to-date coverage of the theory, design and manufacture of heat pipes and their applications. This latest edition has been thoroughly revised, up-dated and expanded to give an in-depth coverage of the new developments in the field. Significant new material has been added to all the chapters and the applications section has been totally rewritten to ensure that topical and important applications are appropriately emphasised. The bibliography has been considerably enlarged to incorporate much valuable new information. Thus readers of the previous edition, which has established

  15. Design and Development of Vision Based Blockage Clearance Robot for Sewer Pipes

    Directory of Open Access Journals (Sweden)

    Krishna Prasad Nesaian

    2012-03-01

    Full Text Available Robotic technology is one of the advanced technologies, which is capable of completing tasks at situations where humans are unable to reach, see or survive. The underground sewer pipelines are the major tools for the transportation of effluent water. A lot of troubles caused by blockage in sewer pipe will lead to overflow of effluent water, sanitation problems. So robotic vehicle that is capable of traveling at underneath effluent water determining blockage using ultrasonic sensors and clearing by means of drilling mechanism is done. In addition to that wireless camera is fixed which acts as a robot vision by which we can monitor video and capture images using MATLAB tool. Thus in this project a prototype model of underground sewer pipe blockage clearance robot with drilling type will be developed

  16. Design of an ultra-high torque double shoulder drill-pipe tool joint for extended reach wells

    Directory of Open Access Journals (Sweden)

    Xiaohua Zhu

    2017-09-01

    Full Text Available Drill-pipe tool joints in extended reach wells often suffer a shear failure. In view of this, an ultra-high torque double-shoulder pipe joint was designed according to the deformation compatibility relation of the drill-pipe tool joint under torque. It is structurally characterized by long primary and secondary shoulders, small thread taper and large fillet radius of bottom tooth. First, a 3D numerical simulation model was established for this type of joint, named the XSJ joint here, based on the principle of virtual work, the Von Mises yield criterion and the nonlinear contact theory. Second, orthogonal optimization was performed on its key structural parameters by means of the orthogonal optimization method. The optimal combination of key structural parameters of the XSJ joint is taper 1:16, thread pitch 6.55 mm, guiding surface angle 29°, bearing surface angle 28°, and tooth height 3.755 mm. Finally, the bearing performance and fatigue performance of this tool joint and the API tool joint were calculated and compared using the Simulia Abaqus fe-safe software. Compared with the API tool joint, the XSJ joint is better, and its tensile strength, torsion strength, bending strength and compression strength increase by 10.65%, 62.5%, 2.75% and 52%, respectively. Its tension compression fatigue life, bending fatigue life, torsion fatigue life and composite fatigue life increase by 1.19 times, 1.74 times, 550 times and 28.79%, respectively. It is concluded that the designed XSJ joint is significantly improved in term of torsion capacity while its tension strength, bending strength and compression strength are not decreased, so it can better meet the drilling conditions of extended reach wells. Keywords: Extended reach well, Tool joint, Shear failure, Torsion capacity, Bending capacity, Orthogonal optimization, Bearing property, Fatigue life

  17. Design and experimental gait analysis of a multi-segment in-pipe robot inspired by earthworm's peristaltic locomotion

    Science.gov (United States)

    Fang, Hongbin; Wang, Chenghao; Li, Suyi; Xu, Jian; Wang, K. W.

    2014-03-01

    This paper reports the experimental progress towards developing a multi-segment in-pipe robot inspired by earthworm's body structure and locomotion mechanism. To mimic the alternating contraction and elongation of a single earthworm's segment, a robust, servomotor based actuation mechanism is developed. In each robot segment, servomotor-driven cords and spring steel belts are utilized to imitate the earthworm's longitudinal and circular muscles, respectively. It is shown that the designed segment can contract and relax just like an earthworm's body segment. The axial and radial deformation of a single segment is measured experimentally, which agrees with the theoretical predictions. Then a multisegment earthworm-like robot is fabricated by assembling eight identical segments in series. The locomotion performance of this robot prototype is then extensively tested in order to investigate the correlation between gait design and dynamic locomotion characteristics. Based on the principle of retrograde peristalsis wave, a gait generator is developed for the multi-segment earthworm-like robot, following which gaits of the robot can be constructed. Employing the generated gaits, the 8-segment earthworm-like robot can successfully perform both horizontal locomotion and vertical climb in pipes. By changing gait parameters, i.e., with different gaits, locomotion characteristics including average speed and anchor slippage can be significantly tailored. The proposed actuation method and prototype of the multi-segment in-pipe robot as well as the gait generator provide a bionic realization of earthworm's locomotion with promising potentials in various applications such as pipeline inspection and cleaning.

  18. Load analysis of hypothetical ruptures and optimum design of anti-whip restraint devices for VVP and ARE high energy pipes in NPPs

    International Nuclear Information System (INIS)

    Zhang Xingtian; Cao Feng; Ding Youyuan; Wang Jianjun; Qiu Wenjun

    2010-01-01

    In order to deal with the dynamic effects induced by the imagined ruptures of the VVP and ARE high energy pipes in Nuclear power plants, incident results analysis and release methods must be adopted based on the stress analysis and fatigue calculations. This article not only gives the calculation methods of jet forces, jet energy and characteristic lengths of VVP and ARE high energy pipes ruptures based on the optimum mechanic mode, discusses the rupture locations of the VVP high energy pipes according to the RCC-P and RCC-M codes, but also presents one new bilinearity method which could be used for the design and modification of the H type and U type anti-whip restraint devices for VVP and ARE high energy pipes. This article provides important references for the domestic production of the H type and U type anti-whip restraint devices. (authors)

  19. Piping research program plan

    International Nuclear Information System (INIS)

    1988-09-01

    This document presents the piping research program plan for the Structural and Seismic Engineering Branch and the Materials Engineering Branch of the Division of Engineering, Office of Nuclear Regulatory Research. The plan describes the research to be performed in the areas of piping design criteria, environmentally assisted cracking, pipe fracture, and leak detection and leak rate estimation. The piping research program addresses the regulatory issues regarding piping design and piping integrity facing the NRC today and in the foreseeable future. The plan discusses the regulatory issues and needs for the research, the objectives, key aspects, and schedule for each research project, or group of projects focussing of a specific topic, and, finally, the integration of the research areas into the regulatory process is described. The plan presents a snap-shot of the piping research program as it exists today. However, the program plan will change as the regulatory issues and needs change. Consequently, this document will be revised on a bi-annual basis to reflect the changes in the piping research program. (author)

  20. Surface Curvatures and Diffraction Profiles of Sagittaly Bent Laue Crystals

    Energy Technology Data Exchange (ETDEWEB)

    Shi, X.; Takacs, P.; Ghose, S.; Zhong, Z.; Rehak, M.L.; Kaznatcheev, K.; Dooryhee, E.

    2011-05-17

    The performance of a bent Laue crystal monochromator crucially depends on the sagittal and meridional bending curvatures of the crystal. To optimize the design of monochromator crystals, the surface curvatures and diffraction profiles of a set of sagittally bent Laue crystals with different aspect ratios have been studied experimentally by optical metrology and X-ray measurements. The results were confirmed with finite-element analysis using large-deformation theory. The nonlinear relationship between the curvatures necessitates an experimentally determined parameter in the theoretical modeling of the diffraction profiles. By taking into account the local stress and the aspect ratio of the sagittally bent Laue crystal, the modified analytical approach successfully predicts the rocking-curve width and the integrated reflecting power. The effect of extreme sagittal bending on the rocking curve is also discussed. To retain high reflectivity, the bending curvature should not exceed its critical value for the specified crystal geometry. Furthermore, the uniformity of the bending curvatures across the crystal surface has been examined, which suggests that the minimum crystal dimension should be approximately twice the size of the beam footprint.

  1. Main Design Principles of the Cold Beam Pipe in the FastRamped Superconducting Accelerator Magnets for Heavy Ion Synchrotron SIS100

    Science.gov (United States)

    Mierau, A.; Schnizer, P.; Fischer, E.; Macavei, J.; Wilfert, S.; Koch, S.; Weiland, T.; Kurnishov, R.; Shcherbakov, P.

    SIS100, the world second large scale heavy ion synchrotron using fast ramped superconducting magnets, is to be built at FAIR. Its high current operation of intermediate charge state ions requires stable vacuum pressures technological feasible design solutions, three opposite requirements have to be met: minimum magnetic field distortion caused by AC losses, mechanical stability and low and stable wall temperatures of the beam pipe. We present the possible design versions of the beam pipe for the high current curved dipole. The pros and cons of these proposed designs were studied using simplified analytical models, FEM calculations and tests on models.

  2. Basic studies on computer aided concurrent engineering for hull structure design and piping design; Kakugi ittai wo koryoshita doji heikotekina sekkei no shien ni kansuru kisoteki kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Aoyama, K.; Sawada, K. [The University of Tokyo, Tokyo (Japan)

    1996-12-31

    Considering integrated hull and piping design in shipbuilding industry as a good example for concurrent engineering (CE), discussions were given on a computer aided method to perform integrated hull and piping design smoothly. When CE aiding by means of a computer is considered, it is important to discuss a method for information management not only for `utilization of product models`, but also for `maintaining consistency between items of product information` and `concurrent utilization and production of product information` in concurrent designs. For the CE aided information management, utilization and production of the product information is effective if restrictive relationship between items of product information, and design functions are made clear. Definitions were given on the restrictive relationship between items of product information and `restrictive relationship information` that has `decision/provisional decision`, `date and time`, `designer` and `design functions`. Furthermore, `comprehensive relationship between items of product information` that can be produced from the restrictive relationship information was defined as a `restrictive network`. Utilizing the restrictive relationship between items of product information for CE aiding is effective. 9 refs., 14 figs.

  3. The Structure Design and Simulation of Ultrasonic Inspection Instrument for Inside Pressurized Pipe Elbows

    Science.gov (United States)

    Miao, Cunjian; Du, Xingji; Xia, Junfang; Wang, Min; Ling, Zhangwei; Tang, Ping

    2018-01-01

    Elbows in pressure pipes are important parts which may become serious corrosion locations. Ultrasonic detection is a main technique for pipe inner inspection, and the use of traditional ultrasound and phased array technique for in-line inspection are advanced, long-term interesting and known by researchers. Several devices were invented for inside pipeline inspection and suitable to some extent such as detecting long-distance pipelines. However, elbows especially tight elbows are still difficult to implement inner detection or travelling. To obtain good effect in detecting elbows, the inner inspection technique was investigated. Spherical and flat cylindrical probe holder structures were proposed to ensure the ability to pass through elbows, while the spherical holder has many conventional probes in its shell with a uniform distribution. The flat cylindrical probe structures are suitable for phased array ultrasonic technique to form a convex array. CIVA simulation was conducted and the focal effects were analyzed. Comparing with detecting precision and manufacture process, the phased array technique was chosen, and the elbow inspection experiments were carried out. The ultrasonic system was taken by a robot to travel through the elbow, and the experimental data were used to verify the applicability of the ultrasonic inspection technique.

  4. Optimized Design of Thermoelectric Energy Harvesting Systems for Waste Heat Recovery from Exhaust Pipes

    Directory of Open Access Journals (Sweden)

    Marco Nesarajah

    2017-06-01

    Full Text Available With the increasing interest in energy efficiency and resource protection, waste heat recovery processes have gained importance. Thereby, one possibility is the conversion of the heat energy into electrical energy by thermoelectric generators. Here, a thermoelectric energy harvesting system is developed to convert the waste heat from exhaust pipes, which are very often used to transport the heat, e.g., in automobiles, in industrial facilities or in heating systems. That is why a mockup of a heating is built-up, and the developed energy harvesting system is attached. To build-up this system, a model-based development process is used. The setup of the developed energy harvesting system is very flexible to test different variants and an optimized system can be found in order to increase the energy yield for concrete application examples. A corresponding simulation model is also presented, based on previously developed libraries in Modelica®/Dymola®. In the end, it can be shown—with measurement and simulation results—that a thermoelectric energy harvesting system on the exhaust pipe of a heating system delivers extra energy and thus delivers a contribution for a more efficient usage of the inserted primary energy carrier.

  5. Welded joints engineering design of the primary circuit, surge line and main steam piping of the Angra 2 reactor

    International Nuclear Information System (INIS)

    Volta, Angelo Roberto; Couto, Jose Gonzalo Villaverde

    1995-01-01

    The erection of nuclear systems of a Nuclear Power Station is under international requests, that results in a detailed elaboration of documents for the performance of welds. NUCLEN as an engineering design company, responsible for the erection of Angra 2, developed a suitable software program for the elaboration of welding procedure qualifications, tests and examination sequence plans and heat treatment plans applied to primary circuit, surgeline and main steam piping. The paper shows the employed methodology for the elaboration of these documents, as well as the requested engineering design of welding technology and testability in order to assure the stipulated quality level, according to requirements of the specifications, codes and norms. (author). 6 refs

  6. Coupling sections, emittance growth, and drift compensation in the use of bent solenoids as beam transport elements

    Directory of Open Access Journals (Sweden)

    J. Norem

    1999-05-01

    Full Text Available Bent solenoids can transmit charged particle beams while providing momentum dispersion. While less familiar than quadrupole and dipole systems, bent solenoids can produce superficially simple transport lines and large acceptance spectrometers for use at low energies. Design issues such as drift compensation and coupling sections between straight and bent solenoids are identified, and aberrations such as shears produced by perpendicular error fields are discussed. Examples are considered which provide the basis for the design of emittance exchange elements for the cooling system of a muon collider.

  7. NEP heat pipe radiators. [Nuclear Electric Propulsion

    Science.gov (United States)

    Ernst, D. M.

    1979-01-01

    This paper covers improvements of heat pipe radiators for the thermionic NEP design. Liquid metal heat pipes are suitable as spacecraft radiator elements because of high thermal conductance, low mass and reliability, but the NEP thermionic system design was too large and difficult to fabricate. The current integral collector-radiator design consisting of several layers of thermionic converters, the annular-tangential collector heat pipe, the radiator heat pipe, and the transition zone designed to minimize the temperature difference between the collector heat pipe and radiator heat pipe are described. Finally, the design of micrometeoroid armor protection and the fabrication of the stainless steel annular heat pipe with a tangential arm are discussed, and it is concluded that the heat rejection system for the thermionic NEP system is well advanced, but the collector-radiator heat pipe transition and the 8 to 10 m radiator heat pipe with two bends require evaluation.

  8. Load analysis of hypothetical ruptures and optimum design of H-type anti-whip restraint devices for high energy pipes based on bilinearity method

    International Nuclear Information System (INIS)

    Zhang Xingtian; Cao Feng; Ding Youyuan; Wang Jianjun; Fang Jiang

    2011-01-01

    In order to deal with the dynamic effects induced by the hypothetical ruptures of the high energy pipes in nuclear power plants, the physical isolation and anti-whip restraint devices should be adopted based on the mechanical analysis during the NPP design. This paper not only introduces the calculation methods of jet forces, jet energy and characteristic lengths of circumferential rupture of high energy pipes based on the optimum mechanic mode, but also presents one new bilinearity method which could be used for the design and verification of the H type anti-whip restraint devices. (authors)

  9. Comparative study of design of piping supports class 1, 2 and 3 considering german code KTA and ASME III - NF

    International Nuclear Information System (INIS)

    Faloppa, Altair A.; Fainer, Gerson; Mattar Neto, Miguel; Elias, Marcos V.

    2013-01-01

    The objective of this paper is developing a comparative study of the design criteria for class 1, 2, 3 piping supports considering the American Code ASME Section III - NF and the German Code KTA 3205.1 to the Primary Circuit, KTA 3205.2 to the others systems and KTA 3205.3 series-production standards supports of a PWR nuclear power plant. An additional purpose of the paper is a general analysis of the main design concepts of the American Code ASME Boiler and Pressure Vessel Code, Section III, Division 1 and German Nuclear Design Code KTA that was performed in order to aid the comparative study proposed. The relevance of this study is to show the differences between codes ASME and KTA since they were applied in the design of the Nuclear Power Plants Angra 1 and Angra 2, and to the design of Angra 3, which is at the moment under construction. It is also considered their use in the design of nuclear installations such as RMB - Reator MultiProposito Brasileiro and LABGENE - Laboratorio de Geracao Nucleoeletrica. (author)

  10. Design and fabrication of polymer-concrete-lined pipe for testing in geothermal-energy processes. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Kaeding, A.O.

    1981-12-01

    A specific polymer-concrete formulation was applied as a steel pipe liner in response to a need for durable, economical materials for use in contact with high temperature geothermal brine. Processes are described for centrifugally applying the liner to straight pipe, for casting the liner in pipe fittings, and for closure of field joints. Physical properties of the liner materials were measured. Compressive strengths of up to 165.8 MPa (24,045 psi) and splitting tensile strengths of 23.5 MPa (3408 psi) were measured at ambient temperature. Compressive strengths of 24 MPa (3490 psi) and splitting tensile strengths of 2.5 MPa (366 psi) were measured at about 150/sup 0/C (302/sup 0/F). A full-scale production plant is described which would be capable of producing about 950 m (3120 ft) of lined 305-mm-diam (12 in.) pipe per day. Capital cost of the plant is estimated to be about $8.6 million with a calculated return on investment of 15.4%. Cost of piping a geothermal plant with PC and PC-lined steel pipe is calculated to be $1.21 million, which compares favorably with a similar plant piped with alloy steel piping at a cost of $1.33 million. Life-cycle cost analysis indicates that the cost of PC-lined steel pipe would be 82% of that of carbon steel pipe over a 20-year plant operating life.

  11. Reliability analysis of stiff versus flexible piping

    International Nuclear Information System (INIS)

    Lu, S.C.

    1985-01-01

    The overall objective of this research project is to develop a technical basis for flexible piping designs which will improve piping reliability and minimize the use of pipe supports, snubbers, and pipe whip restraints. The current study was conducted to establish the necessary groundwork based on the piping reliability analysis. A confirmatory piping reliability assessment indicated that removing rigid supports and snubbers tends to either improve or affect very little the piping reliability. The authors then investigated a couple of changes to be implemented in Regulatory Guide (RG) 1.61 and RG 1.122 aimed at more flexible piping design. They concluded that these changes substantially reduce calculated piping responses and allow piping redesigns with significant reduction in number of supports and snubbers without violating ASME code requirements. Furthermore, the more flexible piping redesigns are capable of exhibiting reliability levels equal to or higher than the original stiffer design. An investigation of the malfunction of pipe whip restraints confirmed that the malfunction introduced higher thermal stresses and tended to reduce the overall piping reliability. Finally, support and component reliabilities were evaluated based on available fragility data. Results indicated that the support reliability usually exhibits a moderate decrease as the piping flexibility increases. Most on-line pumps and valves showed an insignificant reduction in reliability for a more flexible piping design

  12. Monofluorinated unsymmetrical bent-core mesogens

    NARCIS (Netherlands)

    Achten, R.; Smits, E.A.W.; Reddy, R.A.; Giesbers, M.; Marcelis, A.T.M.; Sudhölter, E.J.R.

    2006-01-01

    The synthesis and mesomorphic properties of 30 bent-core compounds with a fluorine substituent in one of the outer rings are reported. The banana-shaped compounds are all derived from resorcinol and contain esters as linking groups between the five aromatic rings. The different mesophases have been

  13. Wees de controller die u bent

    NARCIS (Netherlands)

    Smit, Marion

    2017-01-01

    Want wie u bent heeft invloed op hoe u uw rol als controller invult, net als uw rol als controller weer invloed heeft op uw identiteit. Een functie is geen objectief of statisch gat waar u in moet passen. Uw collega-controller maakt er iets anders van, de manager verwacht ook wat anders en zelfs de

  14. Summary of design of nuclear vessels and piping to ASME III (NB, NC, ND) and vessels to BS 5500

    International Nuclear Information System (INIS)

    Harrop, L.P.

    1992-01-01

    There is a hierarchy of design code requirements for pressurised components, starting with non-nuclear codes as the minimum and progressing through the ASME III nuclear Classes 3, 2, 1. In establishing and assessing the safety justifications of nuclear plants it is important to have an appreciation of the gradation of requirements in the ASME III design rules and how these go beyond non-nuclear component design rules. There are two broad aspects to the structural integrity of pressurised components, namely the achievement of integrity and the demonstration of integrity. The technical requirements of design codes are associated with achieving integrity while the documentary aspects are usually associated with demonstrating integrity. In practice documents also have a part in achieving integrity in the communication of information between different organisations and personnel involved in the design process. It is not possible to assign simple numerical measures to the relative integrity afforded by non-nuclear codes and the three Classes of ASME III. Instead it is necessary to compare the different requirements of the rules for the various technical and documentary aspects. This paper summarises the most important technical and documentary aspects of the three Classes of the ASME III Code for vessels and the non-nuclear code BS 5500. A similar summary is also provided for the three Classes of ASME III rules for piping. The intention is that the paper provides a basis for appreciating the relative integrity afforded by these various rules. (author)

  15. Analysis of Circular Polarization of Cylindrically Bent Microstrip Antennas

    Directory of Open Access Journals (Sweden)

    Tiiti Kellomäki

    2012-01-01

    Full Text Available When circularly polarized (CP microstrip antennas are bent, the polarization becomes elliptical. We present a simple model that describes the phenomenon. The two linear modes present in a CP patch are modeled separately and added together to produce CP. Bending distorts the almost-spherical equiphase surface of a linearly polarized patch, which leads to phase imbalance in the far-field of a CP patch. The model predicts both the frequency shifting of the axial ratio band as well as the narrowing of the axial ratio beam. Uncontrolled bending is a problem associated especially with flexible textile antennas, and wearable antennas should therefore be designed somewhat conformal.

  16. A new family of four-ring bent-core nematic liquid crystals with highly polar transverse and end groups

    Directory of Open Access Journals (Sweden)

    Kalpana Upadhyaya

    2013-01-01

    Full Text Available Non-symmetrically substituted four-ring achiral bent-core compounds with polar substituents, i.e.., chloro in the bent or transverse direction in the central core and cyano in the lateral direction at one terminal end of the molecule, are designed and synthesized. These molecules possess an alkoxy chain attached at only one end of the bent-core molecule. The molecular structure characterization is consistent with data from elemental and spectroscopic analysis. The materials thermal behaviour and phase characterization have been investigated by differential scanning calorimetry and polarizing microscopy. All the compounds exhibit a wide-ranging monotropic nematic phase.

  17. Best practices for quality management of stormwater pipe construction.

    Science.gov (United States)

    2014-02-01

    Stormwater pipe systems are integral features of transportation construction projects. Pipe culverts : direct stormwater away from roadway structures and towards designated discharge areas. The improper : installation of a pipe culvert can result in ...

  18. 46 CFR 153.294 - Marking of piping systems.

    Science.gov (United States)

    2010-10-01

    ... CARRYING BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Design and Equipment Piping Systems and Cargo Handling Equipment § 153.294 Marking of piping systems. (a) Each cargo piping system...

  19. 46 CFR 153.281 - Piping to independent tanks.

    Science.gov (United States)

    2010-10-01

    ... CARRYING BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Design and Equipment Piping Systems and Cargo Handling Equipment § 153.281 Piping to independent tanks. Piping for an independent...

  20. Literature review and experimental investigation of heat pipes

    Science.gov (United States)

    Barsch, W. O.; Schoenhals, R. J.; Viskanta, R.; Winter, E. R. F.

    1971-01-01

    Tests on heat pipes determine operational limits, external boundary conditions, noncondensable gas effects, startup behavior, and geometric configurations. Experiment consists of design, construction, and testing of an apparatus for measuring wick properties, conventional heat pipes and coplanar heat pipes.

  1. Bent and branched chains of nanoresonators

    Science.gov (United States)

    Melikhova, A. S.; Popov, I. Yu

    2014-10-01

    We study the spectral problem for bent and branched chains of weakly coupled conglobate resonators. At the joint points the δ-coupling is assumed. Our approach is based on the theory of self-adjoint extensions of symmetric operators and transfer matrix method. The structure of the spectrum is described. For the both cases it is proved that the Hamiltonian has negative eigenvalue for some values of the model parameters.

  2. Compensation for gravitational sag of bent mirror

    International Nuclear Information System (INIS)

    Mao, Chengwen; Jiang, Hui; He, Yan; Liang, Dongxu; Lan, Xuying; Yan, Shuai; Shu, De-ming; Li, Aiguo

    2017-01-01

    The gravitational sag of aspheric bent mirrors with face-up or face-down geometry produces a nonnegligible optical error. As an effective compensation, width optimization is used to match the combined effects of the gravitational and bending moments. This method is described by analytical expressions and two calculation algorithms. The results of theoretical simulations and finite element analysis have proved that this method can reduce the slope error resulting from gravitational sag to the level of nano radians.

  3. Compensation for gravitational sag of bent mirror

    Energy Technology Data Exchange (ETDEWEB)

    Mao, Chengwen; Jiang, Hui; He, Yan; Liang, Dongxu; Lan, Xuying; Yan, Shuai [Shanghai Synchrotron Radiation Facility, Shanghai Institute of Applied Physics, CAS, Shanghai 201800 (China); Shu, De-ming [Advanced Photon Source, Argonne National Laboratory, Argonne, IL 60439 (United States); Li, Aiguo, E-mail: aiguo.li@sinap.ac.cn [Shanghai Synchrotron Radiation Facility, Shanghai Institute of Applied Physics, CAS, Shanghai 201800 (China)

    2017-05-01

    The gravitational sag of aspheric bent mirrors with face-up or face-down geometry produces a nonnegligible optical error. As an effective compensation, width optimization is used to match the combined effects of the gravitational and bending moments. This method is described by analytical expressions and two calculation algorithms. The results of theoretical simulations and finite element analysis have proved that this method can reduce the slope error resulting from gravitational sag to the level of nano radians.

  4. Novel polymerizable bent-shaped monomeric molecules

    Czech Academy of Sciences Publication Activity Database

    Kozmik, V.; Kovářová, A.; Kuchař, M.; Svoboda, Jiří; Novotná, Vladimíra; Glogarová, Milada; Kroupa, Jan

    2006-01-01

    Roč. 33, č. 1 (2006), s. 41-56 ISSN 0267-8292 R&D Projects: GA ČR(CZ) GA202/05/0431; GA MŠk(CZ) OC D14.50 Institutional research plan: CEZ:AV0Z10100520 Keywords : mesogens * polymerizable * bent-shaped molecules * liquid crystals * ferroelectricity Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.417, year: 2006

  5. Heat pipes

    CERN Document Server

    Dunn, Peter D

    1994-01-01

    It is approximately 10 years since the Third Edition of Heat Pipes was published and the text is now established as the standard work on the subject. This new edition has been extensively updated, with revisions to most chapters. The introduction of new working fluids and extended life test data have been taken into account in chapter 3. A number of new types of heat pipes have become popular, and others have proved less effective. This is reflected in the contents of chapter 5. Heat pipes are employed in a wide range of applications, including electronics cooling, diecasting and injection mo

  6. A bent Laue-Laue monochromator for a synchrotron-based computed tomography system

    International Nuclear Information System (INIS)

    Ren, B.; Dilmanian, F.A.; Chapman, L.D.; Ivanov, I.; Wu, X.Y.; Zhong, Z.; Huang, X.

    1999-01-01

    We designed and tested a two-crystal bent Laue-Laue monochromator for wide, fan-shaped synchrotron X-ray beams for the program multiple energy computed tomography (MECT) at the National Synchrotron Light Source (NSLS). MECT employs monochromatic X-ray beams from the NSLS's X17B superconducting wiggler beamline for computed tomography (CT) with an improved image quality. MECT uses a fixed horizontal fan-shaped beam with the subject's apparatus rotating around a vertical axis. The new monochromator uses two Czochralski-grown Si crystals, 0.7 and 1.4 mm thick, respectively, and with thick ribs on their upper and lower ends. The crystals are bent cylindrically, with the axis of the cylinder parallel to the fan beam, using 4-rod benders with two fixed rods and two movable ones. The bent-crystal feature of the monochromator resolved the difficulties we had had with the flat Laue-Laue design previously used in MECT, which included (a) inadequate beam intensity, (b) excessive fluctuations in beam intensity, and (c) instability of the shape of the beam's horizontal profile. Compared with that earlier monochromator, the bent Laue-Laue device tested at 42 and 108 keV showed about a 10-fold larger beam flux, about 5 times better beam stability, 10-fold less harmonic contamination, and a smaller energy bandwidth at certain bending radii. The present work gave us better understanding of the basis for the beam-smiling effect in bent-crystal monochromators, and allowed us to refine the theoretical method of estimating the beam-harmonic contamination in bent-crystal monochromators

  7. PIPE STRESS and VERPIP codes for stress analysis and verifications of PEC reactor piping

    International Nuclear Information System (INIS)

    Cesari, F.; Ferranti, P.; Gasparrini, M.; Labanti, L.

    1975-01-01

    To design LMFBR piping systems following ASME Sct. III requirements unusual flexibility computer codes are to be adopted to consider piping and its guard-tube. For this purpose PIPE STRESS code previously prepared by Southern-Service, has been modified. Some subroutine for detailed stress analysis and principal stress calculations on all the sections of piping have been written and fitted in the code. Plotter can also be used. VERPIP code for automatic verifications of piping as class 1 Sct. III prescriptions has been also prepared. The results of PIPE STRESS and VERPIP codes application to PEC piping are in section III of this report

  8. Pipe grabber

    Energy Technology Data Exchange (ETDEWEB)

    Sharafutdinov, I.G.; Mubashirov, S.G.; Prokopov, O.I.

    1981-05-15

    A pipe grabber is suggested which contains a housing, clamping elements and centering mechanism with drive installed on the lower end of the housing. In order to improve the reliable operation of the pipe grabber, the centering mechanism is made in the form of a reinforced ringed flexible shaft, while the drive is made in the form of elastic rotating discs. In this case the direction of rotation of the discs and the flexible shaft is the opposite.

  9. Design parameters for single pipe thermal insulation systems for offshore flow assurance

    Energy Technology Data Exchange (ETDEWEB)

    Jackson, Adam; Johnsen, Erik; Kopystynski, Adam; Simonsen, Eirik; Boye-Hansen, Allan [Bredero Shaw (Thermotite), Orkanger (Norway)

    2005-07-01

    Limit state design of subsea thermal insulation systems has been shown to be feasible and robust. This requires careful implementation of extensive long-term laboratory data and property models into verified FEA / FDA tools. Such simulations allow for the determination of not only the steady state response, but also the transient response of the system as a function of temperature, hydrostatic loading, ageing, water ingress and time. This departure from the traditional use of monolithic thermal conductivities, heat capacities and water absorption values can allow in some cases for a reduction in the thickness of insulation, whilst simultaneously enabling control of conservatism. The current paper discusses the important influences affecting the performance of insulant systems and the results of verification testing along with design examples where the generally accepted design method is compared to the limit state approach. (author)

  10. Design Considerations for Lightweight Space Radiators Based on Fabrication and Test Experience With a Carbon-Carbon Composite Prototype Heat Pipe. Revised

    Science.gov (United States)

    Juhasz, Albert J.

    2002-01-01

    This report discusses the design implications for spacecraft radiators made possible by the successful fabrication and proof-of-concept testing of a graphite-fiber-carbon-matrix composite (i.e., carbon-carbon (C-C)) heat pipe. The prototype heat pipe, or space radiator element, consists of a C-C composite shell with integrally woven fins. It has a thin-walled furnace-brazed metallic (Nb-1%Zr) liner with end caps for containment of the potassium working fluid. A short extension of this liner, at increased wall thickness beyond the C-C shell, forms the heat pipe evaporator section which is in thermal contact with the radiator fluid that needs to be cooled. From geometric and thermal transport properties of the C-C composite heat pipe tested, a specific radiator mass of 1.45 kg/sq m can be derived. This is less than one-fourth the specific mass of present day satellite radiators. The report also discusses the advantage of segmented space radiator designs utilizing heat pipe elements, or segments, in their survivability to micrometeoroid damage. This survivability is further raised by the use of condenser sections with attached fins, which also improve the radiation heat transfer rate. Since the problem of heat radiation from a fin does not lend itself to a closed analytical solution, a derivation of the governing differential equation and boundary conditions is given in appendix A, along with solutions for rectangular and parabolic fin profile geometries obtained by use of a finite difference computer code written by the author.

  11. Design Considerations for Lightweight Space Radiators Based on Fabrication and Test Experience with a Carbon-Carbon Composite Prototype Heat Pipe

    Science.gov (United States)

    Juhasz, Albert J.

    1998-01-01

    This report discusses the design implications for spacecraft radiators made possible by the successful fabrication and Proof-of-concept testing of a graphite-fiber-carbon-matrix composite (i.e., carbon-carbon (C-C)) heat pipe. The proto-type heat pipe, or space radiator element, consists of a C-C composite shell with integrally woven fins. It has a thin-walled furnace-brazed metallic (Nb-1%Zr) liner with end caps for containment of the potassium working fluid. A short extension of this liner, at increased wall thickness beyond the C-C shell, forms the heat pipe evaporator section which is in thermal contact with the radiator fluid that needs to be cooled. From geometric and thermal transport properties of the C-C composite heat pipe tested, a specific radiator mass of 1.45 kg/m2 can be derived. This is less than one-fourth the specific mass of present day satellite radiators. The report also discusses the advantage of segmented space radiator designs utilizing heat pipe elements, or segments, in their survivability to micro-meteoroid damage. This survivability is further raised by the use of condenser sections with attached fins, which also improve the radiation heat transfer rate. Since the problem of heat radiation from a fin does not lend itself to a closed analytical solution, a derivation of the governing differential equation and boundary conditions is given in appendix A, along with solutions for rectangular and parabolic fin profile geometries obtained by use of a finite difference computer code written by the author.

  12. Recent development of aseismic design practice of equipment and piping system in Japan

    International Nuclear Information System (INIS)

    Shibata, H.

    1993-01-01

    Recently, the Japanese practice of aseismic (anti-earthquake) design has been reported on at various occasions, and The Technical Guidelines for Aseismic Design of Nuclear Power Plants, JEAG 4601-1987, published by the Japan Electric Nuclear Regulatory Commission (USNRC). Therefore, it is not necessary to describe these guidelines. However, it is rather difficult to keep a record of why and how decisions which recently were made in Japan. The author describes the process to establish Japanese practice for the first ten years in reference. While the fundamental concept has not been changed since 1961, the details have been modified based on new knowledge obtained from recent research and tests. There has been a continuing effort to make this practice a more rational one

  13. Pipe whip and impact

    International Nuclear Information System (INIS)

    Attwood, G.J.

    1987-01-01

    Over the past few years changes in economic and safety considerations in nuclear power plants have resulted in a need to examine the problem of pipe whip in greater detail. Consequently, experimental programmes were set up in France, North America and Britain. Results from these tests combined with analytical work indicate that pipe whip followed by impact with surrounding pipework and structures may not be as serious as had been believed. Impact loads have been found to be much less (at least five times) than those predicted to the appropriate design regulations. Hence, the use of pipe whip restraints may have been overconservative. The use of fewer, better designed restraints, would result in greater accessibility of pipework, a reduced need for inspection of restraints, and a considerable financial saving. (author)

  14. Large-bore pipe decontamination

    International Nuclear Information System (INIS)

    Ebadian, M.A.

    1998-01-01

    The decontamination and decommissioning (D and D) of 1200 buildings within the US Department of Energy-Office of Environmental Management (DOE-EM) Complex will require the disposition of miles of pipe. The disposition of large-bore pipe, in particular, presents difficulties in the area of decontamination and characterization. The pipe is potentially contaminated internally as well as externally. This situation requires a system capable of decontaminating and characterizing both the inside and outside of the pipe. Current decontamination and characterization systems are not designed for application to this geometry, making the direct disposal of piping systems necessary in many cases. The pipe often creates voids in the disposal cell, which requires the pipe to be cut in half or filled with a grout material. These methods are labor intensive and costly to perform on large volumes of pipe. Direct disposal does not take advantage of recycling, which could provide monetary dividends. To facilitate the decontamination and characterization of large-bore piping and thereby reduce the volume of piping required for disposal, a detailed analysis will be conducted to document the pipe remediation problem set; determine potential technologies to solve this remediation problem set; design and laboratory test potential decontamination and characterization technologies; fabricate a prototype system; provide a cost-benefit analysis of the proposed system; and transfer the technology to industry. This report summarizes the activities performed during fiscal year 1997 and describes the planned activities for fiscal year 1998. Accomplishments for FY97 include the development of the applicable and relevant and appropriate regulations, the screening of decontamination and characterization technologies, and the selection and initial design of the decontamination system

  15. Promethus Hot Leg Piping Concept

    International Nuclear Information System (INIS)

    AM Girbik; PA Dilorenzo

    2006-01-01

    The Naval Reactors Prime Contractor Team (NRPCT) recommended the development of a gas cooled reactor directly coupled to a Brayton energy conversion system as the Space Nuclear Power Plant (SNPP) for NASA's Project Prometheus. The section of piping between the reactor outlet and turbine inlet, designated as the hot leg piping, required unique design features to allow the use of a nickel superalloy rather than a refractory metal as the pressure boundary. The NRPCT evaluated a variety of hot leg piping concepts for performance relative to SNPP system parameters, manufacturability, material considerations, and comparison to past high temperature gas reactor (HTGR) practice. Manufacturability challenges and the impact of pressure drop and turbine entrance temperature reduction on cycle efficiency were discriminators between the piping concepts. This paper summarizes the NRPCT hot leg piping evaluation, presents the concept recommended, and summarizes developmental issues for the recommended concept

  16. Piping engineering for nuclear power plant

    International Nuclear Information System (INIS)

    Curto, N.; Schmidt, H.; Muller, R.

    1988-01-01

    In order to develop piping engineering, an adequate dimensioning and correct selection of materials must be secured. A correct selection of materials together with calculations and stress analysis must be carried out with a view to minimizing or avoiding possible failures or damages in piping assembling, which could be caused by internal pressure, weight, temperature, oscillation, etc. The piping project for a nuclear power plant is divided into the following three phases. Phase I: Basic piping design. Phase II: Final piping design. Phase III: Detail engineering. (Author)

  17. Bent crystal X-ray optics for the diagnosis and applications of laser-produced plasmas

    International Nuclear Information System (INIS)

    Loetzsch, Robert

    2012-01-01

    The present thesis discussed several aspects of X-ray optics based on bent crystals and a number of applications of these optics. First, a deeper insight into the reflection properties of elastically bent perfect crystal optics was gained by the consideration of all deformation effects. It was shown that the reflection properties depend on the lateral position on the crystal, an effect that was not addressed before, neither experimentally nor theoretically. To investigate this effect, an apparatus for the measurement of Bragg angles of bent crystals with high angular resolution was built. It was measured that the lattice plane distances of two-dimensionally bent crystals vary laterally by up to 10 -4 . This effect has to be considered in high resolution X-ray spectroscopy and imaging with these bent crystals. It can explain discrepancies in theoretical and experimental spectrometer resolution with spherically bent crystals. Besides these principal investigations, in this thesis a number of X-ray optics were presented that demonstrate the application potential of bent crystal optics. This includes two optics that are used in the field of applications of laser-produced plasmas as high repeating hard X-ray sources. It was shown that an X-ray spectrometer based on full cylinder rings of highly oriented pyrolytic graphite is capable to record the rather weak single shot pulses from a high repeating 1 er-plasma X-ray source. This is possible due to the high collection efficiency of the instrument of up to 5.10 -4 . Furthermore, X-ray optics based on toroidally bent crystals that make it possible to spectrally select a bandwidth of ∝1 eV and focus the ultrashort X-ray pulses from such a laser-plasma source, were designed, prepared and characterized. It was shown that these bent crystals provide the calculated integrated reflectivity, the predicted bandwidth and focus to spot sizes smaller than 60 μm. A novel application of toroidally bent crystals was pointed out: a

  18. Steering of sub-GeV electrons by ultrashort Si and Ge bent crystals

    Energy Technology Data Exchange (ETDEWEB)

    Sytov, A.I. [Ferrara Univ. (Italy). Dipt. di Fisica e Scienze della Terra; Belarusian State Univ., Minsk (Belarus). Inst. for Nuclear Problems; INFN Sezione di Ferrara (Italy); Bandiera, L.; Mazzolari, A.; Bagli, E.; Germogli, G.; Guidi, V.; Romagnoni, M. [Ferrara Univ. (Italy). Dipt. di Fisica e Scienze della Terra; INFN Sezione di Ferrara (Italy); De Salvador, D.; Carturan, S.; Maggioni, G. [INFN, Laboratori Nazionali di Legnaro (Italy); Padova Univ. (Italy). Dipt. di Fisica; Berra, A.; Prest, M. [Univ. dell' Insubria, Como (Italy); INFN, Sezione di Milano Bicocca, Milan (Italy); Durighello, C. [Ferrara Univ. (Italy). Dipt. di Fisica e Scienze della Terra; INFN, Laboratori Nazionali di Legnaro (Italy); Padova Univ. (Italy). Dipt. di Fisica; INFN Sezione di Ferrara (Italy); Klag, P.; Lauth, W. [Mainz Univ. (Germany). Inst. fuer Kernphysik; Tikhomirov, V.V. [Belarusian State Univ., Minsk (Belarus). Inst. for Nuclear Problems; Vallazza, E. [INFN, Sezione di Trieste (Italy)

    2017-12-15

    We report the observation of the steering of 855 MeV electrons by bent silicon and germanium crystals at the MAinzer MIkrotron. Crystals with 15 μm of length, bent along (111) planes, were exploited to investigate orientational coherent effects. By using a piezo-actuated mechanical holder, which allowed to remotely change the crystal curvature, it was possible to study the steering capability of planar channeling and volume reflection vs. the curvature radius and the atomic number, Z. For silicon, the channeling efficiency exceeds 35%, a record for negatively charged particles. This was possible due to the realization of a crystal with a thickness of the order of the dechanneling length. On the other hand, for germanium the efficiency is slightly below 10% due to the stronger contribution of multiple scattering for a higher-Z material. Nevertheless this is the first evidence of negative beam steering by planar channeling in a Ge crystal. Having determined for the first time the dechanneling length, one may design a Ge crystal based on such knowledge providing nearly the same channeling efficiency of silicon. The presented results are relevant for crystal-based beam manipulation as well as for the generation of e.m. radiation in bent and periodically bent crystals. (orig.)

  19. Steering of Sub-GeV electrons by ultrashort Si and Ge bent crystals

    Science.gov (United States)

    Sytov, A. I.; Bandiera, L.; De Salvador, D.; Mazzolari, A.; Bagli, E.; Berra, A.; Carturan, S.; Durighello, C.; Germogli, G.; Guidi, V.; Klag, P.; Lauth, W.; Maggioni, G.; Prest, M.; Romagnoni, M.; Tikhomirov, V. V.; Vallazza, E.

    2017-12-01

    We report the observation of the steering of 855 MeV electrons by bent silicon and germanium crystals at the MAinzer MIkrotron. Crystals with 15 μ m of length, bent along (111) planes, were exploited to investigate orientational coherent effects. By using a piezo-actuated mechanical holder, which allowed to remotely change the crystal curvature, it was possible to study the steering capability of planar channeling and volume reflection vs. the curvature radius and the atomic number, Z. For silicon, the channeling efficiency exceeds 35%, a record for negatively charged particles. This was possible due to the realization of a crystal with a thickness of the order of the dechanneling length. On the other hand, for germanium the efficiency is slightly below 10% due to the stronger contribution of multiple scattering for a higher-Z material. Nevertheless this is the first evidence of negative beam steering by planar channeling in a Ge crystal. Having determined for the first time the dechanneling length, one may design a Ge crystal based on such knowledge providing nearly the same channeling efficiency of silicon. The presented results are relevant for crystal-based beam manipulation as well as for the generation of e.m. radiation in bent and periodically bent crystals.

  20. Develop Strong and Serviceable Details for Precast, Prestressed Concrete Bent Cap Standards That Can Be Implemented on Everyday Bridge Construction Projects, Project Summary

    Science.gov (United States)

    2018-01-01

    Pretensioned bent caps are an attractive substructure component because they offer contractors an option for fabrication by prestressing plants and can be used to eliminate or reduce cracks. Two sets of design recommendations were developed to enable...

  1. Modelling and performance of heat pipes with long evaporator sections

    NARCIS (Netherlands)

    Wits, Wessel W.; te Riele, Gert Jan

    2017-01-01

    This paper presents a planar cooling strategy for advanced electronic applications using heat pipe technology. The principle idea is to use an array of relatively long heat pipes, whereby heat is disposed to a long section of the pipes. The proposed design uses 1 m long heat pipes and top cooling

  2. Evaluation of fracture toughness of nuclear piping using real pipe and tensile compact pipe specimens

    International Nuclear Information System (INIS)

    Koo, J.M.; Park, S.; Seok, C.S.

    2013-01-01

    Highlights: • The tensile compact pipe (CP) specimen was proposed. • J-integral for the specimen was obtained by the plastic limit load analysis and FEA. • Fracture toughness tests by several types of specimens were performed and compared. • The constraint effects were considered by comparing Q-stresses for them. -- Abstract: The leak-before-break (LBB) concept is generally used to design the primary heat transport piping for a nuclear power plant. The LBB concept is based on the fracture resistance curve, which is obtained by J–R tests on various types of specimens. Fracture toughness data differ according to the various types of specimens. It has also been known that there is a difference in the constraint effect between real pipes and standard specimens, and LBB design using standard specimens is conservative. We propose a new type of specimen for J–R tests, a tensile compact pipe (CP) specimen, and perform fracture toughness tests on various types of specimens. We also perform constraint effect analysis on such specimens. The Q-stresses of the tensile CP specimens are lower than those of real pipes under 4-point bending, and are higher than those of elbow pipes. If the lever length of a tensile CP specimen is controlled, the specimen can simulate various stress conditions, and it is thought that the LBB design of piping in service can be performed using this specimen

  3. Evaluation of fracture toughness of nuclear piping using real pipe and tensile compact pipe specimens

    Energy Technology Data Exchange (ETDEWEB)

    Koo, J.M.; Park, S.; Seok, C.S., E-mail: seok@skku.edu

    2013-06-15

    Highlights: • The tensile compact pipe (CP) specimen was proposed. • J-integral for the specimen was obtained by the plastic limit load analysis and FEA. • Fracture toughness tests by several types of specimens were performed and compared. • The constraint effects were considered by comparing Q-stresses for them. -- Abstract: The leak-before-break (LBB) concept is generally used to design the primary heat transport piping for a nuclear power plant. The LBB concept is based on the fracture resistance curve, which is obtained by J–R tests on various types of specimens. Fracture toughness data differ according to the various types of specimens. It has also been known that there is a difference in the constraint effect between real pipes and standard specimens, and LBB design using standard specimens is conservative. We propose a new type of specimen for J–R tests, a tensile compact pipe (CP) specimen, and perform fracture toughness tests on various types of specimens. We also perform constraint effect analysis on such specimens. The Q-stresses of the tensile CP specimens are lower than those of real pipes under 4-point bending, and are higher than those of elbow pipes. If the lever length of a tensile CP specimen is controlled, the specimen can simulate various stress conditions, and it is thought that the LBB design of piping in service can be performed using this specimen.

  4. On the basic research of design analysis and testing based on the failure rate for pipings and equipment under earthquake conditions

    International Nuclear Information System (INIS)

    Shibata, H.

    1980-01-01

    This paper deals with the evaluation method of the failure rate of pipings and equipment of nuclear power plants under destructive earthquakes and a new design concept in this stand point of view. These researches are supported by various studies related to this subject, which have been done by the author since 1966. In this paper, the history of the development, the summaries of these studies and their significances to the practice will be described briefly. The surveys on damages of industrial facilities caused by recent destructive earthquakes are the basical study for this subject. And the continuous response observation of model structures of a plant complex to natural earthquakes is another important basic study to know the stochastic nature and significance of response analysis for the anti-earthquake design of nuclear power plants. By having the exact knowledges on these subjects, the author has been developing the evaluation procedure of the failure rate of pipings and equipment under destructive earthquake conditions, a new design method 'counter-input design' and others. Now his effort is going towards establishing their practical procedure after finishing the basic researches. (orig.)

  5. Evaluation procedure of the structural integrity of a pipe of nuclear use. Application of codes for design and service. Case study

    International Nuclear Information System (INIS)

    Sanzi, H.; Asta, E.

    2009-01-01

    In the present work, we are presenting the most important results of the local stresses occurred in the cracked pipes with a axial through-wall, under Failure Concept 0.1A, using Finite Element Method and Fracture Mechanics. As requested, the component has been verified based 3D FE plastic analysis, under the postulated failure loading, assuring with this method a high degree of accuracy in the results. Codes used by Design and Service, as ASME Section III Div. 1 and API 579, have been used in the analysis. (author)

  6. Pulsatile turbulent flow through pipe bends at high Dean and Womersley numbers

    International Nuclear Information System (INIS)

    Kalpakli, Athanasia; Örlü, Ramis; Tillmark, Nils; Alfredsson, P Henrik

    2011-01-01

    Turbulent pulsatile flows through pipe bends are prevalent in internal combustion engine components which consist of bent pipe sections and branching conduits. Nonetheless, most of the studies related to pulsatile flows in pipe bends focus on incompressible, low Womersley and low Dean number flows, primarily because they aim in modeling blood flow, while internal combustion engine related flows have mainly been addressed in terms of integral quantities and consist of single point measurements. The present study aims at bridging the gap between these two fields by means of time-resolved stereoscopic particle image velocimetry measurements in a pipe bend with conditions that are close to those encountered in exhaust manifolds. The time/phase-resolved three-dimensional cross-sectional flow-field 3 pipe diameters downstream the pipe bend is captured and the interplay between different secondary motions throughout a pulse cycle is discussed.

  7. PPOOLEX experiments with two parallel blowdown pipes

    Energy Technology Data Exchange (ETDEWEB)

    Laine, J.; Puustinen, M.; Raesaenen, A. (Lappeenranta Univ. of Technology, Nuclear Safety Research Unit (Finland))

    2011-01-15

    This report summarizes the results of the experiments with two transparent blowdown pipes carried out with the scaled down PPOOLEX test facility designed and constructed at Lappeenranta University of Technology. Steam was blown into the dry well compartment and from there through either one or two vertical transparent blowdown pipes to the condensation pool. Five experiments with one pipe and six with two parallel pipes were carried out. The main purpose of the experiments was to study loads caused by chugging (rapid condensation) while steam is discharged into the condensation pool filled with sub-cooled water. The PPOOLEX test facility is a closed stainless steel vessel divided into two compartments, dry well and wet well. In the experiments the initial temperature of the condensation pool water varied from 12 deg. C to 55 deg. C, the steam flow rate from 40 g/s to 1 300 g/s and the temperature of incoming steam from 120 deg. C to 185 deg. C. In the experiments with only one transparent blowdown pipe chugging phenomenon didn't occur as intensified as in the preceding experiments carried out with a DN200 stainless steel pipe. With the steel blowdown pipe even 10 times higher pressure pulses were registered inside the pipe. Meanwhile, loads registered in the pool didn't indicate significant differences between the steel and polycarbonate pipe experiments. In the experiments with two transparent blowdown pipes, the steamwater interface moved almost synchronously up and down inside both pipes. Chugging was stronger than in the one pipe experiments and even two times higher loads were measured inside the pipes. The loads at the blowdown pipe outlet were approximately the same as in the one pipe cases. Other registered loads around the pool were about 50-100 % higher than with one pipe. The experiments with two parallel blowdown pipes gave contradictory results compared to the earlier studies dealing with chugging loads in case of multiple pipes. Contributing

  8. 31 CFR 100.11 - Exchange of bent and partial coins.

    Science.gov (United States)

    2010-07-01

    ... 31 Money and Finance: Treasury 1 2010-07-01 2010-07-01 false Exchange of bent and partial coins... OF PAPER CURRENCY AND COIN Exchange of Coin § 100.11 Exchange of bent and partial coins. (a) Definitions. (1) Bent coins are U.S. coins which are bent or deformed so as to preclude normal machine...

  9. Pipe stress analysis on the instrument air in nuclear facilities pipe work

    International Nuclear Information System (INIS)

    Budi Santoso

    2009-01-01

    Piping stress analysis on Instrument Air System have been performed. Analysis carried out to estimate the provision of sufficient flexibility in the piping system to ensure that the heat expansion and contraction of the pipe is still in the allowable stress range. The stress analysis can be used to determine the location and type of support that will be installed. The stress calculation was carried out utilizing the CAESAR on the static load of dead weight, operating and therma. With performing the piping stress analysis, the layout (proper pipe routing) of the piping system can be design with the requirements of piping stress and pipe supports in mind the sufficient flexibility for thermal expansion, etc to commensurate with the intended service such as temperatures, pressure, and anticipated loading. (author)

  10. Elliptically Bent X-Ray Mirrors with Active Temperature Stabilization

    International Nuclear Information System (INIS)

    Yuan, S.; Church, M.; Yashchuk, V.V.; Celestre, R.S.; McKinney, W.R.; Morrison, G.; Warwick, T.; Padmore, H.A.; Goldberg, K.A.; Kirschman, J.; Noll, T.

    2010-01-01

    We present details of design of elliptically bent Kirkpatrick-Baez mirrors developed and successfully used at the advanced light source for submicron focusing. A distinctive feature of the mirror design is an active temperature stabilization based on a Peltier element attached directly to the mirror body. The design and materials have been carefully optimized to provide high heat conductance between the mirror body and substrate. We describe the experimental procedures used when assembling and precisely shaping the mirrors, with special attention paid to laboratory testing of the mirror-temperature stabilization. For this purpose, the temperature dependence of the surface slope profile of a specially fabricated test mirror placed inside a temperature-controlled container was measured. We demonstrate that with active mirror-temperature stabilization, a change of the surrounding temperature by more than 3 K does not noticeably affect the mirror figure. Without temperature stabilization, the rms slope error is changed by approximately 1.5 μrad (primarily defocus) under the same conditions

  11. Bente Boa, Torm, Denmark

    DEFF Research Database (Denmark)

    Wagtmann, Maria Anne

    2009-01-01

    At the beginning of July 2009, Maria Anne Wagtmann (Associate Professor, PhD, University of Southern Denmark) had the opportunity to interview Ms Bente Boa, a senior marine HR manager in the Danish ship owning firm TORM A/S' (http://www.torm.com/). Bente Boa is also chairwoman of the "The Sea Ser...... Serpent" (in Danish: "Søslangen"), a Danish maritime HR network for professionals in maritime firms....

  12. Channeling and radiation in periodically bent crystals

    CERN Document Server

    Korol, Andrey V; Greiner, Walter

    2014-01-01

    The development of coherent radiation sources for sub-angstrom wavelengths - i.e. in the hard X-ray and gamma-ray range -  is a challenging goal of modern physics. The availability of such sources will have many applications in basic science, technology and medicine, and, in particular, they may have a revolutionary impact on nuclear and solid state physics, as well as on the life sciences. The present state-of-the-art lasers are capable of emitting electromagnetic radiation from the infrared to the ultraviolet, while free electron lasers (X-FELs) are now entering the soft X-ray region. Moving further, i.e. into the hard X and/or gamma ray band, however, is not possible without new approaches and technologies.   In this book we introduce and discuss one such novel approach -the radiation formed in a Crystalline Undulator - whereby electromagnetic radiation is generated by a bunch of ultra-relativistic particles channeling through a periodically bent crystalline structure. Under certain conditions, such a d...

  13. Leak before break piping evaluation diagram

    International Nuclear Information System (INIS)

    Fabi, R.J.; Peck, D.A.

    1994-01-01

    Traditionally Leak Before Break (LBB) has been applied to the evaluation of piping in existing nuclear plants. This paper presents a simple method for evaluating piping systems for LBB during the design process. This method produces a piping evaluation diagram (PED) which defines the LBB requirements to the piping designer for use during the design process. Several sets of LBB analyses are performed for each different pipe size and material considered in the LBB application. The results of this method are independent of the actual pipe routing. Two complete LBB evaluations are performed to determine the maximum allowable stability load, one evaluation for a low normal operating load, and the other evaluation for a high normal operating load. These normal operating loads span the typical loads for the particular system being evaluated. In developing the allowable loads, the appropriate LBB margins are included in the PED preparation. The resulting LBB solutions are plotted as a set of allowable curves for the maximum design basis load, such is the seismic load versus the normal operating load. Since the required margins are already accounted for in the LBB PED, the piping designer can use the diagram directly with the results of the piping analysis and determine immediately if the current piping arrangement passes LBB. Since the LBB PED is independent of pipe routing, changes to the piping system can be evaluated using the existing PED. For a particular application, all that remains is to confirm that the actual materials and pipe sizes assumed in creating the particular design are built into the plant

  14. Evaluation of clamp effects on LMFBR piping systems

    International Nuclear Information System (INIS)

    Jones, G.L.

    1980-01-01

    Loop-type liquid metal breeder reactor plants utilize thin-wall piping to mitigate through-wall thermal gradients due to rapid thermal transients. These piping loops require a support system to carry the combined weight of the pipe, coolant and insulation and to provide attachments for seismic restraints. The support system examined here utilizes an insulated pipe clamp designed to minimize the stresses induced in the piping. To determine the effect of these clamps on the pipe wall a non-linear, two-dimensional, finite element model of the clamp, insulation and pipe wall was used to determine the clamp/pipe interface load distributions which were then applied to a three-dimensional, finite element model of the pipe. The two-dimensional interaction model was also utilized to estimate the combined clamp/pipe stiffness

  15. Development of residual stress measurement apparatus by neutron diffraction and its application to bent carbon steel

    International Nuclear Information System (INIS)

    Hayashi, Makoto; Ohkido, Shinobu; Minakawa, Nobuaki; Morii, Yukio

    1998-01-01

    To establish the measuring technique of neutron diffraction for the internal residual stress distribution in a structural component, a neutron diffraction apparatus was designed and manufactured in Modified Japan Research Reactor 3 (JRR3M). At the first step of measurement, a basic characteristics of the diffractometer was evaluated. The incident neutron beam flux was 10 4 n/cm 2 /sec and the Full Width at Half Maximum (FWHM) was about 0.3 degree. This indicates that the manufactured neutron diffractometer is capable for the residual stress measurement. As the first application of the neutron diffraction measurement, the residual stress distribution in plastically bent carbon steel plate was measured. A typical compressive-tensile-compressive-tensile residual stress pattern in the tangential direction in the bent plane was confirmed. The maximum stress near the surface was about 180 MPa. This means that the technique for residual stress measurement by neutron diffraction can be established in Japan. (author)

  16. Piping reliability improvement through passive seismic supports

    International Nuclear Information System (INIS)

    Baltus, R.; Rubbers, A.

    1999-01-01

    The nuclear plants designed in the 1970's were equipped with large quantities of snubbers in auxiliary piping systems. The experience revealed a poor performance of snubbers during periodic inspection, while non-nuclear facility piping survived through strong earthquakes. Consequently, seismic design rules evolved towards more realistic criteria and passive dynamic supports were developed to reduce snubber quantities. These solutions improve the pipe reliability during normal operation while reducing the radiation exposure in a sample line is presented with the impact on pipe stresses compared to the results obtained with passive supports named Limit Stops. (author)

  17. Resolution of concerns in auxiliary feedwater piping

    International Nuclear Information System (INIS)

    Bain, R.A.; Testa, M.F.

    1994-01-01

    Auxiliary feedwater piping systems at pressurized water reactor (PWR) nuclear power plants have experienced unanticipated operating conditions during plant operation. These unanticipated conditions have included plant events involving backleakage through check valves, temperatures in portions of the auxiliary feedwater piping system that exceed design conditions, and the occurrence of unanticipated severe fluid transients. The impact of these events has had an adverse effect at some nuclear stations on plant operation, installed plant components and hardware, and design basis calculations. Beaver Valley Unit 2, a three loop pressurized water reactor nuclear plant, has observed anomalies with the auxiliary feedwater system since the unit went operational in 1987. The consequences of these anomalies and plant events have been addressed and resolved for Beaver Valley Unit 2 by performing engineering and construction activities. These activities included pipe stress, pipe support and pipe rupture analysis, the monitoring of auxiliary feedwater system temperature and pressure, and the modification to plant piping, supports, valves, structures and operating procedures

  18. Pipe support optimization in nuclear power plants

    International Nuclear Information System (INIS)

    Cleveland, A.B.; Kalyanam, N.

    1984-01-01

    A typical 1000 MWe nuclear power plant consists of 80,000 to 100,000 feet of piping which must be designed to withstand earthquake shock. For the required ground motion, seismic response spectra are developed for safety-related structures. These curves are used in the dynamic analysis of piping systems with pipe-stress analysis computer codes. To satisfy applicable Code requirements, the piping systems also require analysis for weight, thermal and possibly other lasting conditions. Bechtel Power Corporation has developed a design program called SLAM (Support Location Algorithm) for optimizing pipe support locations and types (rigid, spring, snubber, axial, lateral, etc.) while satisfying userspecified parameters such as locations, load combinations, stress and load allowables, pipe displacement and cost. This paper describes SLAM, its features, applications and benefits

  19. Beam screens for the LHC beam pipes

    CERN Multimedia

    Patrice Loïez

    1997-01-01

    Cross-section of LHC prototype beam pipes showing the beam screens. Slits in the screens allow residual gas molecules to be pumped out and become frozen to the walls of the ultra-cold beam pipe. Beam screens like these have been designed to line the beam pipes, absorbing radiation before it can hit the magnets and warm them up, an effect that would greatly reduce the magnetic field and cause serious damage.

  20. Experimental analytical study on heat pipes

    International Nuclear Information System (INIS)

    Ismail, K.A.R.; Liu, C.Y.; Murcia, N.

    1981-01-01

    An analytical model is developed for optimizing the thickness distribution of the porous material in heat pipes. The method was used to calculate, design and construct heat pipes with internal geometrical changes. Ordinary pipes are also constructed and tested together with the modified ones. The results showed that modified tubes are superior in performance and that the analytical model can predict their performance to within 1.5% precision. (Author) [pt

  1. Design and rationale of a matched cohort study to assess the effectiveness of a combined household-level piped water and sanitation intervention in rural Odisha, India.

    Science.gov (United States)

    Reese, Heather; Routray, Parimita; Torondel, Belen; Sclar, Gloria; Delea, Maryann G; Sinharoy, Sheela S; Zambrano, Laura; Caruso, Bethany; Mishra, Samir R; Chang, Howard H; Clasen, Thomas

    2017-03-31

    Government efforts to address massive shortfalls in rural water and sanitation in India have centred on construction of community water sources and toilets for selected households. However, deficiencies with water quality and quantity at the household level and community coverage and actual use of toilets have led Gram Vikas, a local non-governmental organization in Odisha, India, to develop an approach that provides household-level piped water connections contingent on full community-level toilet coverage. This matched cohort study was designed to assess the effectiveness of a combined piped water and sanitation intervention. Households with children environmental enteric dysfunction. In addition, intervention effects on sanitation and water coverage, access and use, environmental fecal contamination, women's empowerment, as well as collective efficacy, and intervention cost and cost-effectiveness will be assessed. The study protocol has been reviewed and approved by the ethics boards of the London School of Hygiene and Tropical Medicine, UK and KIIT University, Bhubaneswar, India. Findings will be disseminated via peer-reviewed literature and presentation to stakeholders, government officials, implementers and researchers. NCT02441699. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  2. 46 CFR 153.283 - Valving for cargo piping.

    Science.gov (United States)

    2010-10-01

    ... CARRYING BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Design and Equipment Piping Systems and Cargo Handling Equipment § 153.283 Valving for cargo piping. (a) Except as described in this...

  3. Microcomputer generated pipe support calculations

    International Nuclear Information System (INIS)

    Hankinson, R.F.; Czarnowski, P.; Roemer, R.E.

    1991-01-01

    The cost and complexity of pipe support design has been a continuing challenge to the construction and modification of commercial nuclear facilities. Typically, pipe support design or qualification projects have required large numbers of engineers centrally located with access to mainframe computer facilities. Much engineering time has been spent repetitively performing a sequence of tasks to address complex design criteria and consolidating the results of calculations into documentation packages in accordance with strict quality requirements. The continuing challenges of cost and quality, the need for support engineering services at operating plant sites, and the substantial recent advances in microcomputer systems suggested that a stand-alone microcomputer pipe support calculation generator was feasible and had become a necessity for providing cost-effective and high quality pipe support engineering services to the industry. This paper outlines the preparation for, and the development of, an integrated pipe support design/evaluation software system which maintains all computer programs in the same environment, minimizes manual performance of standard or repetitive tasks, and generates a high quality calculation which is consistent and easily followed

  4. The mechanical and hygrothermal behavior of composite piping: Notes on the methodology of dimensioning and structural design

    International Nuclear Information System (INIS)

    Perreux, D.; Varchon, D.; Lebras, J.

    1995-01-01

    The production of electricity in power plants is directly linked to the duration and frequency of partial shutdowns. In order to be free of the problems of corrosion of the secondary metallic circuit which lead to lengthy shutdowns, Electricite de France (EDF) decided to substitute these circuits with those made from composite materials. In this paper the criteria of damage beginning for laminate pipes is discussed. The material is a glass-epoxy laminate manufactured by a winding filament process and is used for water pipelining. First of all a description of the damage is performed in order to define a damage variable. Thanks to the elastic energy an associated variable is defined. The damage criteria is written by using this last one. The parameter of the criteria is identified by mechanical and acoustical methods. The result is compared and exhibits good agreement

  5. The bent crystal diffraction spectrometer at the BR2 reactor in Mol

    Science.gov (United States)

    Kaerts, E.; Jacobs, L.; Vandenput, G.; Van Assche, P. H. M.

    1988-05-01

    The DuMond-type bent crystal diffraction spectrometer installed at the BR2 reactor in Mol is presented. The spectrometer is mainly designed to study nuclear γ-transitions following thermal neutron capture. It covers the energy interval 25 ≦ Eγ ≦ 1500 keV. Instead of the traditionally used quartz crystals, a highly perfect silicium crystal is chosen as analysing crystal. Diffraction occurs from the (220) plane. The "quasi-mosaic" width, introduced by bending the crystal, is as small as 0.2″. The integrated reflecting power R of the bent crystal stays constant up to 1.5 MeV in first, 680 keV in second and 300 keV in third diffraction order. For higher photon energies, only an E-1 energy dependence is observed in second and third diffraction order. Consequently, besides improving the energy resolution, the use of these silicium crystals substantially increases the spectrometer efficiency and extends the high energy limit of bent crystal diffraction spectrometers. The diffraction angles are measured with a symmetrical interferometer system which covers an angular range of -6° to +6° with a precision of about 0.01″. Minimum diffraction line widths of 0.9″ have been measured, corresponding to an energy resolution ΔE = 1.35 × 10 -6E2n-1 keV -1. The dominant contribution to the observed line widths arises from the finite extent of the source.

  6. Short bent-core molecules: X-ray, polarization, dielectricity, texture and electro-optics investigations.

    Science.gov (United States)

    Torgova, S; Sreenilayam, S P; Panarin, Yu P; Francescangeli, O; Vita, F; Vij, J K; Pozhidaev, E; Minchenko, M; Ferrero, C; Strigazzi, A

    2017-08-30

    Bent-core liquid crystals based on 1,2,4-oxadiazole as a central unit have been the first mesogens to exhibit a ferroelectric response in the nematic phase. This behavior has been widely recognized as due to the presence of smectic-like polar cybotactic clusters permeating the nematic phase. Unfortunately, these compounds exhibited rather high melting points, about 120 °C, due to the presence of four benzene rings in the molecules. Here we describe the synthesis and physical characterization of a new series of BC mesogens, featuring the same bent core as the previous compounds but shorter outer substituents. By keeping only two benzene rings, we were able to lower the melting points to about 70 °C. However, while X-ray diffraction and dielectric spectroscopy measurements confirm the cybotactic nature of the nematic phase of these compounds, polarization and electro-optical measurements ascribe their polar response to flexoelectricity rather than to spontaneous polarization. Finally, texture investigation suggests the biaxiality of the nematic phase, which is indicated also by conoscopic measurements. These results are important for recognizing size and rigidity limitations in designing bent-core liquid crystal molecules suitable for applications.

  7. Application of displacement monitoring system on high temperature steam pipe

    Science.gov (United States)

    Ghaffar, M. H. A.; Husin, S.; Baek, J. E.

    2017-10-01

    High-energy piping systems of power plants such as Main Steam (MS) pipe or Hot Reheat (HR) pipe are operating at high temperature and high pressure at base and cyclic loads. In the event of transient condition, a pipe can be deflected dramatically and caused high stress in the pipe, yielding to failure of the piping system. Periodic monitoring and walk down can identify abnormalities but limitations exist in the standard walk down practice. This paper provides a study of pipe displacement monitoring on MS pipe of coal-fired power plant to continuously capture the pipe movement behaviour at different load using 3-Dimensional Displacement Measuring System (3DDMS). The displacement trending at Location 5 and 6 (north and south) demonstrated pipes displace less than 25% to that of design movement. It was determined from synchronisation analysis that Location 7 (north) and Location 8 (south) pipe actual movement difference has exceeded the design movement difference. Visual survey at specified locations with significant displacement trending reveals issues of hydraulic snubber and piping interferences. The study demonstrated that the displacement monitoring is able to capture pipe movement at all time and allows engineer to monitor pipe movement behaviour, aids in identifying issue early for remedy action.

  8. Defect rates in butt welded steel pipes

    International Nuclear Information System (INIS)

    Guille-Stevens, D.; Silcock, P.

    1980-01-01

    As the primary circuit of CANDU reactors consists largely of pipe, the reliability of pipe welds is of interest to reactor designers. A project involving 64 000 manual and semi-automatic pipe welds was inspected to the requirements of ANSI B31.3. Records of 6 000 carbon steel and 1 900 alloy steel butt welds ranging from 50 to 400 mm were inspected by radiography and ultrasonics, and analysed. No correlation between defects and number of weld passes was observed. However, small pipes exhibited a higher defect rate, per weld length and per weld volume, than did large pipes. Porosity was the major cause of defects (60 per cent) followed by root defects (27 per cent); only one crack was recorded. The results show that small (50 mm) pipe welds have the highest defect rate; however, the low overall rate shows that high standards can be maintained over many thousand welds [af

  9. Boomwhackers and End-Pipe Corrections

    Science.gov (United States)

    Ruiz, Michael J.

    2014-02-01

    End-pipe corrections seldom come to mind as a suitable topic for an introductory physics lab. Yet, the end-pipe correction formula can be verified in an engaging and inexpensive lab that requires only two supplies: plastic-tube toys called boomwhackers and a meterstick. This article describes a lab activity in which students model data from plastic tubes to arrive at the end-correction formula for an open pipe. Students also learn the basic mathematics behind the musical scale, and come to appreciate the importance of end-pipe physics in the engineering design of toy musical tubes.

  10. Imperfection analysis of flexible pipe armor wires in compression and bending

    DEFF Research Database (Denmark)

    Østergaard, Niels Højen; Lyckegaard, Anders; Andreasen, Jens H.

    2012-01-01

    The work presented in this paper is motivated by a specific failure mode known as lateral wire buckling occurring in the tensile armor layers of flexible pipes. The tensile armor is usually constituted by two layers of initially helically wound steel wires with opposite lay directions. During pipe...... laying in ultra deep waters, a flexible pipe experiences repeated bending cycles and longitudinal compression. These loading conditions are known to impose a danger to the structural integrity of the armoring layers, if the compressive load on the pipe exceeds the total maximum compressive load carrying...... ability of the wires. This may cause the wires to buckle in the circumferential pipe direction, when these are restrained against radial deformations by adjacent layers. In the present paper, a single armoring wire modeled as a long and slender curved beam embedded in a frictionless cylinder bent...

  11. An investigation of wall temperature characteristics to evaluate thermal fatigue at a T-junction pipe

    International Nuclear Information System (INIS)

    Miyoshi, Koji; Nakamura, Akira; Utanohara, Yoichi; Takenaka, Nobuyuki

    2014-01-01

    Thermal fatigue cracking may initiate at a T-junction pipe where high and low temperature fluids mix. In this study, wall temperature characteristics at a T-junction pipe were investigated to improve the evaluation method for thermal fatigue. The stainless steel test section consisted of a horizontal main pipe (diameter, 150 mm) and a T-junction connected to a vertical branch pipe (diameter, 50 mm). The inlet flow velocities in the main and branch pipes were set to 0.99 m/s and 0.66 m/s respectively to produce a wall jet pattern in which the jet from the branch pipe was bent by the main pipe flow and made to flow along the pipe wall. The temperature difference was 34.1 K. A total of 148 thermocouples were installed to measure the wall temperature on the pipe inner surface in the downstream region. The maximum of temperature fluctuation intensity on the pipe inner surface was measured as 5% of the fluid temperature difference at the inlets. The dominant frequency of the large temperature fluctuations in the region downstream from z = 0.5D m was equal to 0.2 of the Strouhal number, which was equal to the frequency caused by the vortex streets generated around the jet flow. The large temperature fluctuation was also observed with the period of about 10 s. The fluctuation was caused by spreading of the heated region in the circumferential direction. (author)

  12. Structural evaluation of the Main Steam Isolation Valve (MSIV) room under loads from the Pipe Rupture Hazard Analysis (PRHA) and the associated detailed design

    Energy Technology Data Exchange (ETDEWEB)

    Di Fonzo, M.G.; Quintero, F.; Moraleda, F.

    2015-07-01

    Currently Westinghouse Electric Spain develops part of the generic design of the new Nuclear Power Plants. The enclosure for which the Main Steam Line (MSL) and the Main Feed Water Line (MFWL) run must withstand the loads from pipes breaks (PRHA). The finned-floor and the wall adjacent to Main Control Room (MCR) are of principal concerns. The reason for that is due to under the finned-floor and on the other side of the wall there are several control systems necessary for the Safe Shutdown Condition. Starting from the basic design we proceed to evaluate structurally the finned-floor and the wall of the enclosure using the criteria stated in ACI-349-01. Several finite elements models and ANSYSTM macros were developed in order to evaluate the structural response under all of the load combinations. The results were used for the design of the structural components of the MSIV room and also for reinforcing the local zones where the supports are anchored. The final conclusion is that the enclosure design complies not only with the requirements of the structural integrity but also with the NRC, 10CFR Part 50, Appendix A, “General Design Criterion 4”. (Author)

  13. Giant flexoelectricity of bent-core nematic liquid crystals.

    Science.gov (United States)

    Harden, J; Mbanga, B; Eber, N; Fodor-Csorba, K; Sprunt, S; Gleeson, J T; Jákli, A

    2006-10-13

    Flexoelectricity is a coupling between orientational deformation and electric polarization. We present a direct method for measuring the flexoelectric coefficients of nematic liquid crystals (NLCs) via the electric current produced by periodic mechanical flexing of the NLC's bounding surfaces. This method is suitable for measuring the response of bent-core liquid crystals, which are expected to demonstrate a much larger flexoelectric effect than traditional, calamitic liquid crystals. Our results reveal that not only is the bend flexoelectric coefficient of bent-core NLCs gigantic (more than 3 orders of magnitude larger than in calamitics) but also it is much larger than would be expected from microscopic models based on molecular geometry. Thus, bent-core nematic materials can form the basis of a technological breakthrough for conversion between mechanical and electrical energy.

  14. Liquid crystal elastomers: Bent core flexo-electricity

    Science.gov (United States)

    Chambers, Martin; Verduzco, Rafael; Sprunt, Samuel; Gleeson, James T.; Jakli, Antal

    2009-03-01

    We report on the swelling of calamitic liquid crystal elastomers (LCE) with bent-core mesogens (BCM); this swelling took place at a temperature where both materials were in their isotropic phase. The BCM used varied in the degree of saturation of their hydrocarbon tails, which affects both viscosity and phase behaviour. We determined both swelling magnitude and dynamics. The host LCE systems homogeneously imbibe BCM up to 30-40 % mol. Based on differential scanning calorimetry, shape change anisotropy, and optical birefringence measurements, the swollen elastomers are all found to exhibit nematic phases, with some possessing a lower temperature smectic phase. Bent-core liquid crystal elastomers and swollen calamitic LCE in BCM were investigated for the flexoelectric properties by inducing a mechanical deformation. The value of the bend flexoelectric constant, e3 of the swollen BCM containing LCE systems is comparable of that of the neat bent-core liquid crystal.

  15. The Nematic Phases of Bent-Core Liquid Crystals

    Science.gov (United States)

    Gleeson, Helen F; Kaur, Sarabjot; Görtz, Verena; Belaissaoui, Abdel; Cowling, Stephen; Goodby, John W

    2014-01-01

    Over the last ten years, the nematic phases of liquid crystals formed from bent-core structures have provoked considerable research because of their remarkable properties. This Minireview summarises some recent measurements of the physical properties of these systems, as well as describing some new data. We concentrate on oxadiazole-based materials as exemplars of this class of nematogens, but also describe some other bent-core systems. The influence of molecular structure on the stability of the nematic phase is described, together with progress in reducing the nematic transition temperatures by modifications to the molecular structure. The physical properties of bent-core nematic materials have proven difficult to study, but patterns are emerging regarding their optical and dielectric properties. Recent breakthroughs in understanding the elastic and flexoelectric behaviour are summarised. Finally, some exemplars of unusual electric field behaviour are described. PMID:24700653

  16. Flexible ocean upwelling pipe

    Science.gov (United States)

    Person, Abraham

    1980-01-01

    In an ocean thermal energy conversion facility, a cold water riser pipe is releasably supported at its upper end by the hull of the floating facility. The pipe is substantially vertical and has its lower end far below the hull above the ocean floor. The pipe is defined essentially entirely of a material which has a modulus of elasticity substantially less than that of steel, e.g., high density polyethylene, so that the pipe is flexible and compliant to rather than resistant to applied bending moments. The position of the lower end of the pipe relative to the hull is stabilized by a weight suspended below the lower end of the pipe on a flexible line. The pipe, apart from the weight, is positively buoyant. If support of the upper end of the pipe is released, the pipe sinks to the ocean floor, but is not damaged as the length of the line between the pipe and the weight is sufficient to allow the buoyant pipe to come to a stop within the line length after the weight contacts the ocean floor, and thereafter to float submerged above the ocean floor while moored to the ocean floor by the weight. The upper end of the pipe, while supported by the hull, communicates to a sump in the hull in which the water level is maintained below the ambient water level. The sump volume is sufficient to keep the pipe full during heaving of the hull, thereby preventing collapse of the pipe.

  17. Residual strain distribution in bent composite boiler tubes

    International Nuclear Information System (INIS)

    Tang Fei; Hubbard, Camden R.; Sarma, Gorti; Keiser, James

    2006-01-01

    Kraft recovery boilers are typically constructed of carbon steel boiler tubes clad with a corrosion resistant layer, and these composite tubes are bent and welded together to form air port panels which enable the combustion air to enter the boiler. In this paper, the through-thickness residual strain in the carbon steel layer of non-heat-treated and heat-treated composite bent tubes were measured by neutron diffraction techniques and modeled by finite element modeling. The results can be used to optimize material selection and manufacturing processes to prevent stress corrosion and corrosion fatigue cracking in the boiler tubes

  18. 46 CFR 153.292 - Separation of piping systems.

    Science.gov (United States)

    2010-10-01

    ... CARRYING BULK LIQUID, LIQUEFIED GAS, OR COMPRESSED GAS HAZARDOUS MATERIALS Design and Equipment Piping Systems and Cargo Handling Equipment § 153.292 Separation of piping systems. Cargo piping systems must be arranged so that operations necessary to provide separate systems can be accomplished in a cargo handling...

  19. 30 CFR 75.1905-1 - Diesel fuel piping systems.

    Science.gov (United States)

    2010-07-01

    ... discharge point. (d) If diesel fuel lines are not buried in the ground sufficiently to protect them from... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Diesel fuel piping systems. 75.1905-1 Section... Diesel fuel piping systems. (a) Diesel fuel piping systems from the surface must be designed and operated...

  20. 49 CFR 192.193 - Valve installation in plastic pipe.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Valve installation in plastic pipe. 192.193... Components § 192.193 Valve installation in plastic pipe. Each valve installed in plastic pipe must be designed so as to protect the plastic material against excessive torsional or shearing loads when the valve...

  1. Experimental investigations on an axial grooved cryogenic heat pipe

    Directory of Open Access Journals (Sweden)

    Senthil Kumar Muniappan

    2012-01-01

    Full Text Available This paper deals with development and studies of a trapezoidal axial grooved nitrogen heat pipe. A special liquid nitrogen cryostat has been designed and developed for evaluating the performance of heat pipe where the condenser portion is connected to the cold sink externally. Experiments have been performed on the heat pipe as well as on an equivalent diameter copper rod at different heat loads. The steady state performance of the heat pipe is compared with that of copper rod.

  2. Flow induced vibrations of piping

    International Nuclear Information System (INIS)

    Gibert, R.J.; Axisa, F.

    1977-01-01

    In order to design the supports of piping systems, estimations of the vibrations induced by the fluid conveyed through the pipes are generally needed. For that purpose it is necessary to calculate the model parameters of liquid containing pipes. In most computer codes, fluid effects are accounted for just by adding the fuid mass to the structure. This may lead to serious errors.- Inertial effects from the fluid are not correctly evaluated especially in the case of bended or of non-uniform section pipes. Fluid boundary conditions are simply ignored. - In many practical problems fluid compressibility cannot be negelcted, even in the low frequencies domain which corresponds to efficient excitation by turbulent sources of the flow. This paper presents a method to take into account these efects, by solving a coupled mechanical acoustical problem: the computer code TEDEL of the C.E.A./D.E.M.T. System, based on the finite-elements method, has been extended to calculate simultaneously the pressure fluctuations in the fluid and the vibrations of the pipe. (Auth.)

  3. Numerical and Experimental Investigations of a Rotating Heat Pipe

    Energy Technology Data Exchange (ETDEWEB)

    Jankowski, Todd A. [Univ. of New Mexico, Albuquerque, NM (United States)

    2007-05-01

    Rotating and revolving heat pipes have been used in a variety of applications including heat pipe heat exchangers, cooling of rotating electrical machines, and heat removal in high speed cutting operations. The use of heat pipes in rotating environments has prompted many analytical, numerical, and experimental investigations of the heat transfer characteristics of these devices. Past investigations, however, have been restricted to the study of straight heat pipes. In this work, a curved rotating heat pipe is studied numerically and experimentally. In certain types of rotating machines, heat generating components, which must be cooled during normal operation, are located at some radial distance from the axis of rotation. The bent heat pipe studied here is shown to have advantages when compared to the conventional straight heat pipes in these off-axis cooling scenarios. The heat pipe studied here is built so that both the condenser and evaporator sections are parallel to the axis of rotation. The condenser section is concentric with the axis of rotation while the evaporator section can be placed in contact with off-axis heat sources in the rotating machine. The geometry is achieved by incorporating an S-shaped curve between the on-axis rotating condenser section and the off-axis revolving evaporator section. Furthermore, the heat pipe uses an annular gap wick structure. Incorporating an annular gap wick structure into the heat pipe allows for operation in a non-rotating environment. A numerical model of this rotating heat pipe is developed. The analysis is based on a two-dimensional finite-difference model of the liquid flow coupled to a one-dimensional model of the vapor flow. Although the numerical model incorporates many significant aspects of the fluid flow, the flow in the actual heat pipe is expected to be threedimensional. The rotating heat pipe with the S-shaped curve is also studied experimentally to determine how well the numerical model captures the key

  4. Mesomorphic properties of a bent-shaped liquid crystalline monomer

    Czech Academy of Sciences Publication Activity Database

    Novotná, Vladimíra; Baumeister, U.; Kohout, M.; Svoboda, J.

    2012-01-01

    Roč. 86, č. 5 (2012), 503-515 ISSN 0141-1594 R&D Projects: GA ČR(CZ) GAP204/11/0723 Institutional support: RVO:68378271 Keywords : liquid crystals * bent-shaped mesogen Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.863, year: 2012

  5. Bent Shaped 1, 3, 4-Oxadiazole/Thiadiazole heterocyclic rings ...

    Indian Academy of Sciences (India)

    Two series of bent shaped 1,3,4-oxadiazole/thiadiazole heterocyclic ring containing liquid crystalline (LC) compounds were synthesized and characterized by FT-IR, 1H, 13C-NMR and ESI-Mass spectro-scopic techniques. Liquid crystal properties were investigated by polarized optical microscopy and differential scanning ...

  6. Beam-smiling in bent-Laue monochromators

    International Nuclear Information System (INIS)

    Ren, B.; Dilmanian, F. A.; Wu, X. Y.; Huang, X.; Chapman, L. D.; Ivanov, I.; Zhong, Z.; Thomlinson, W. C.

    1997-01-01

    When a wide fan-shaped x-ray beam is diffracted by a bent crystal in the Laue geometry, the profile of the diffracted beam generally does not appear as a straight line, but as a line with its ends curved up or curved down. This effect, referred to as 'beam-smiling', has been a major obstacle in developing bent-Laue crystal monochromators for medical applications of synchrotron x-ray. We modeled a cylindrically bent crystal using the Finite Element Analysis (FEA) method, and we carried out experiments at the National Synchrotron Light Source and Cornell High Energy Synchrotron Source. Our studies show that, while beam-smiling exists in most of the crystal's area because of anticlastic bending effects, there is a region parallel to the bending axis of the crystal where the diffracted beam is 'smile-free'. By applying asymmetrical bending, this smile-free region can be shifted vertically away from the geometric center of the crystal, as desired. This leads to a novel method of compensating for beam-smiling. We will discuss the method of ''differential bending'' for smile removal, beam-smiling in the Cauchios and the polychromatic geometry, and the implications of the method on developing single- and double-bent Laue monochromators. The experimental results will be discussed, concentrating on specific beam-smiling observation and removal as applied to the new monochromator of the Multiple Energy Computed Tomography [MECT] project of the Medical Department, Brookhaven National Laboratory

  7. Flexoelectricity in an oxadiazole bent-core nematic liquid crystal

    Energy Technology Data Exchange (ETDEWEB)

    Kaur, S., E-mail: Sarabjot.Kaur@manchester.ac.uk; Panov, V. P.; Gleeson, H. F. [School of Physics and Astronomy, University of Manchester, Manchester M13 9PL (United Kingdom); Greco, C.; Ferrarini, A. [Department of Chemical Sciences, University of Padua, Padua I-35131 (Italy); Görtz, V. [Department of Chemistry, University of York, York YO10 5DD (United Kingdom); Department of Chemistry, University of Lancaster, Lancaster LA1 4YB (United Kingdom); Goodby, J. W. [Department of Chemistry, University of York, York YO10 5DD (United Kingdom)

    2014-12-01

    We have determined experimentally the magnitude of the difference in the splay and bend flexoelectric coefficients, |e{sub 1} − e{sub 3}|, of an oxadiazole bent-core liquid crystal by measuring the critical voltage for the formation of flexodomains together with their wave number. The coefficient |e{sub 1} − e{sub 3}| is found to be a factor of 2–3 times higher than in most conventional calamitic nematic liquid crystals, varying from 8 pCm{sup −1} to 20 pCm{sup −1} across the ∼60 K—wide nematic regime. We have also calculated the individual flexoelectric coefficients e{sub 1} and e{sub 3}, with the dipolar and quadrupolar contributions of the bent-core liquid crystal by combining density functional theory calculations with a molecular field approach and atomistic modelling. Interestingly, the magnitude of the bend flexoelectric coefficient is found to be rather small, in contrast to common expectations for bent-core molecules. The calculations are in excellent agreement with the experimental values, offering an insight into how molecular parameters contribute to the flexoelectric coefficients and illustrating a huge potential for the prediction of flexoelectric behaviour in bent-core liquid crystals.

  8. Flexoelectricity in an oxadiazole bent-core nematic liquid crystal

    International Nuclear Information System (INIS)

    Kaur, S.; Panov, V. P.; Gleeson, H. F.; Greco, C.; Ferrarini, A.; Görtz, V.; Goodby, J. W.

    2014-01-01

    We have determined experimentally the magnitude of the difference in the splay and bend flexoelectric coefficients, |e 1 − e 3 |, of an oxadiazole bent-core liquid crystal by measuring the critical voltage for the formation of flexodomains together with their wave number. The coefficient |e 1 − e 3 | is found to be a factor of 2–3 times higher than in most conventional calamitic nematic liquid crystals, varying from 8 pCm −1 to 20 pCm −1 across the ∼60 K—wide nematic regime. We have also calculated the individual flexoelectric coefficients e 1 and e 3 , with the dipolar and quadrupolar contributions of the bent-core liquid crystal by combining density functional theory calculations with a molecular field approach and atomistic modelling. Interestingly, the magnitude of the bend flexoelectric coefficient is found to be rather small, in contrast to common expectations for bent-core molecules. The calculations are in excellent agreement with the experimental values, offering an insight into how molecular parameters contribute to the flexoelectric coefficients and illustrating a huge potential for the prediction of flexoelectric behaviour in bent-core liquid crystals

  9. Trafiksikkerhedseffekten af variable hastighedstavler i åbent land

    DEFF Research Database (Denmark)

    Larsen, Mette Kathrine; Andersen, Camilla Sloth

    2017-01-01

    I trafiksikkerhedsarbejdet er effektstudier væsentlige. Effektstudierne udarbejdes, således at andre vejmyndigheder kan se, hvilke effekter et givent tiltag kan have. I dette studie er der udarbejdet et effektstudie over variable hastighedstavler i åbent land, og yderligere er det undersøgt...

  10. Pipe-to-pipe impact program

    International Nuclear Information System (INIS)

    Alzheimer, J.M.; Bampton, M.C.C.; Friley, J.R.; Simonen, F.A.

    1984-06-01

    This report documents the tests and analyses performed as part of the Pipe-to-Pipe Impact (PTPI) Program at the Pacific Northwest Laboratory. This work was performed to assist the NRC in making licensing decisions regarding pipe-to-pipe impact events following postulated breaks in high energy fluid system piping. The report scope encompasses work conducted from the program's start through the completion of the initial hot oil tests. The test equipment, procedures, and results are described, as are analytic studies of failure potential and data correlation. Because the PTPI Program is only partially completed, the total significance of the current test results cannot yet be accurately assessed. Therefore, although trends in the data are discussed, final conclusions and recommendations will be possible only after the completion of the program, which is scheduled to end in FY 1984

  11. Experimental benchmark for piping system dynamic-response analyses

    International Nuclear Information System (INIS)

    1981-01-01

    This paper describes the scope and status of a piping system dynamics test program. A 0.20 m(8 in.) nominal diameter test piping specimen is designed to be representative of main heat transport system piping of LMFBR plants. Particular attention is given to representing piping restraints. Applied loadings consider component-induced vibration as well as seismic excitation. The principal objective of the program is to provide a benchmark for verification of piping design methods by correlation of predicted and measured responses. Pre-test analysis results and correlation methods are discussed

  12. Experimental benchmark for piping system dynamic-response analyses

    Energy Technology Data Exchange (ETDEWEB)

    1981-01-01

    This paper describes the scope and status of a piping system dynamics test program. A 0.20 m(8 in.) nominal diameter test piping specimen is designed to be representative of main heat transport system piping of LMFBR plants. Particular attention is given to representing piping restraints. Applied loadings consider component-induced vibration as well as seismic excitation. The principal objective of the program is to provide a benchmark for verification of piping design methods by correlation of predicted and measured responses. Pre-test analysis results and correlation methods are discussed.

  13. Calamitic Smectic A-Polar Smectic APA Transition Observed in Bent Molecules with Large Bent-Angle Central Core of 4,6-Dichlorobenzene and Alkylthio Terminal Tail

    Science.gov (United States)

    Nguyen, Ha; Kang, Sungmin; Tokita, Masatoshi; Watanabe, Junji

    2011-07-01

    New homologs of bent molecules with a large bent-angle central core of 4,6-dichloro benzene and an alkylthio terminal tail have been synthesized. Although the corresponding alkoxy-tail homologs show only the calamitic phases because of its large bent angles around 160°, the new homologs with an alkylthio tail exhibit the antiferroelectric smectic APA (SmAPA) banana phase that is transformed on cooling from the calamitic smectic A (SmA) phase. The biaxial polar packing of bent molecules in the SmAPA phase is considered to arise from the hindered rotation around the molecular long axis due to the expansion of the mesophase temperatures to a lower temperature region. This study indicates that the bent molecules, even with a large bent angle, have the potential to form a switchable banana phase with a remarkable decrease in its phase temperature range to around 60 °C.

  14. Designing an artificial neural network using radial basis function to model exergetic efficiency of nanofluids in mini double pipe heat exchanger

    Science.gov (United States)

    Ghasemi, Nahid; Aghayari, Reza; Maddah, Heydar

    2017-12-01

    The present study aims at predicting and optimizing exergetic efficiency of TiO2-Al2O3/water nanofluid at different Reynolds numbers, volume fractions and twisted ratios using Artificial Neural Networks (ANN) and experimental data. Central Composite Design (CCD) and cascade Radial Basis Function (RBF) were used to display the significant levels of the analyzed factors on the exergetic efficiency. The size of TiO2-Al2O3/water nanocomposite was 20-70 nm. The parameters of ANN model were adapted by a training algorithm of radial basis function (RBF) with a wide range of experimental data set. Total mean square error and correlation coefficient were used to evaluate the results which the best result was obtained from double layer perceptron neural network with 30 neurons in which total Mean Square Error(MSE) and correlation coefficient (R2) were equal to 0.002 and 0.999, respectively. This indicated successful prediction of the network. Moreover, the proposed equation for predicting exergetic efficiency was extremely successful. According to the optimal curves, the optimum designing parameters of double pipe heat exchanger with inner twisted tape and nanofluid under the constrains of exergetic efficiency 0.937 are found to be Reynolds number 2500, twisted ratio 2.5 and volume fraction(v/v%) 0.05.

  15. Vibration testing and analysis of a multiply supported piping system

    International Nuclear Information System (INIS)

    Hsieh, B.J.; Kot, C.A.; Srinivasan, M.G.

    1987-01-01

    The behavior of nuclear power plant piping systems during earthquakes, and the most appropriate and economical mode of supporting such piping, is an issue of major concern. Consequently, the verification and validation of piping analysis methods and assumptions used in the design and safety assessment of nuclear power plants are of great interest. As part of its program on the validation of seismic calculational methods, the NR is specifically interested in the validation of the multiple support piping analysis module of the SMACS (Seismic Methodology Analysis Chain with Statistics) computer code. Data for comparing the dynamic behavior of various pipe hanger configurations and validating piping response analyses were recently obtained in the large shaker experiments (SHAG) conducted at the HDR. This paper describes preliminary results from the SHAG piping response tests and the approach taken in the validation of the SMACS code piping analysis. (orig./HP)

  16. Design of a micro-robot with an electro-pneumatic servo-actuator for the intra-pipe inspection; Conception d'un micro robot a actionneur asservi electropneumatique pour l'inspection intratubulaire

    Energy Technology Data Exchange (ETDEWEB)

    Anthierens, C

    1999-12-01

    Micro Electro Mechanical Systems (MEMS) are integrated in many current products and are not only the concern of military defence or medicine. Nowadays micro actuators are diversified by using different kind of energy, and creating different motions. Several applications require small systems to inspect confined and hostile places. Vapour generators in nuclear plants are composed with 3000 to 5000 vertical pipes of 17 mm diameter. These pipes endure high mechanical constraints and have to be inspected to detect eventual cracks. Our study is based on the design, modelling and implementation of a micro-robot enable to move up and carry sensors in these pipes. It moves as an inchworm and then is composed by 2 blocking modules that brace the robot on the pipe sides, and one stretching module that creates a step. This actuator is pneumatic and composed by metal bellows. By this original design, the micro-robot have a good power to volume ratio and thus it can carry a load higher than 1 kg. Its good positioning accuracy is proved with a 90 mm course where the error of positioning is less than 60{mu}m. A PID control law is used to control the robot but state feed back control law is planed. (author)

  17. Design considerations, tooling, and equipment for remote in-service inspection of radioactive piping and pressure-vessel systems

    International Nuclear Information System (INIS)

    Swannack, D.L.; Schmoker, D.S.

    1983-01-01

    This paper summarizes results obtained in use of remotely-operated nondestructive testing (NDT) equipment for inspection of reactor-system components. Experience obtained in operating the Fast Flux Test Facility (FFTF) has provided a basis for field verification of remote NDT equipment designs and has suggested development improvements. Remote Viewing and data gathering systems used include periscopes, borescopes, fiberscopes, hybrid borescopes/fiberscopes, and closed circuit television. A summary of design consideration for inspection equipment and power plant design is presented to achieve improved equipment operation and reduction of plant maintenance downtime

  18. Acoustic Signal Processing for Pipe Condition Assessment (WaterRF Report 4360)

    Science.gov (United States)

    Unique to prestressed concrete cylinder pipe (PCCP), individual wire breaks create an excitation in the pipe wall that may vary in response to the remaining compression of the pipe core. This project was designed to improve acoustic signal processing for pipe condition assessment...

  19. Outlook for a new design application for the joint union geometry of zircaloy-4 pipe-plug welds

    International Nuclear Information System (INIS)

    Martinez, R.L; Corso, H.L; Ausas, J; Fernandez, L

    2008-01-01

    The potential advantages are described and the test results shown for a new joint design for the Zircaloy-4 sheath-plug welding, used in the production of fuel elements for nuclear reactor power generators. Samples taken from sheaths and plugs similar to those used in the Atucha I Reactor were welded using the orbital GTAW process (Gas Tungsten Arc Welding), using a new joint design and equipment that is now applied to the production of high quality welding, with very low levels of contamination. The test results from the experiments with hydrogen content, corrosion, metallographic and traction on samples of these welds are compared with those obtained in simples taken from the conventionally processed fuel elements for Atucha I. The results are also presented for the characterization of samples obtained with the same orbital welding method, but with a smaller protective chamber. This work aimed to verify the influence of the welding chamber size on the contamination with hydrogen. The utility of applying the new design together with the orbital GTAW method to the fabrication process for fuel elements is discussed

  20. Manipulation of hadron beams with bent crystals in circular accelerators

    CERN Document Server

    Rossi, R; Redaelli, S; Scandale, W

    2016-01-01

    Over the past years the understanding and use of coherent interactions of charged particles with ordered crystal lattices has achieved excellent results. Improving collimation of hadron beams in circular accelerators, like the Large Hadron Collider (LHC) of the European Council for Nuclear Research (CERN), it is one of the possible applications. The aim of the UA9 experiment is to demonstrate the feasibility of a two-stage collimation system in the CERN-SPS : the first stage is a bent crystal oriented for an optimal channeling of the incoming halo particles; the second stage is a massive absorber. Two crystals were installed in the LHC last year and a test of crystal assisted collimation at the highest energy will be possible as early as 2015. Finally, the UA9 Collaboration is investigating extraction of particles from a circular accelerator, based on bent crystals.

  1. Converse flexoelectric effect in bent-core nematic liquid crystals.

    Science.gov (United States)

    Kumar, Pramoda; Marinov, Y G; Hinov, H P; Hiremath, Uma S; Yelamaggad, C V; Krishnamurthy, K S; Petrov, A G

    2009-07-09

    We report on the converse flexoelectric effect in two bent-core nematic liquid crystals with opposite dielectric anisotropies. The results are based on electro-optic investigations of inplane field-driven distortions in homeotropic samples (the Helfrich method). They are interpreted by an extension of the Helfrich theory that takes into account the higher order distortions. The bend flexocoefficient for both the compounds is of the usual order of magnitude as in calamitics, unlike in a previously investigated bent-core nematic for which giant values of the bend flexocoefficient are reported. In order to resolve this discrepancy, we propose a molecular model with nonpolar clusters showing quadrupolar flexoelectricity. The study also includes measurements on surface polarization instabilities in the dielectrically positive material; the splay flexocoefficient thereby deduced is also of the conventional order.

  2. Manufacture of mold of polymeric composite water pipe reinforced charcoal

    Science.gov (United States)

    Zulfikar; Misdawati; Idris, M.; Nasution, F. K.; Harahap, U. N.; Simanjuntak, R. K.; Jufrizal; Pranoto, S.

    2018-03-01

    In general, household wastewater pipelines currently use thermoplastic pipes of Polyvinyl Chloride (PVC). This material is known to be not high heat resistant, contains hazardous chemicals (toxins), relatively inhospitable, and relatively more expensive. Therefore, researchers make innovations utilizing natural materials in the form of wood charcoal as the basic material of making the water pipe. Making this pipe requires a simple mold design that can be worked in the scale of household and intermediate industries. This research aims to produce water pipe mold with simple design, easy to do, and making time relatively short. Some considerations for molding materials are weight of mold, ease of raw material, strong, sturdy, and able to cast. Pipe molds are grouped into 4 (four) main parts, including: outer diameter pipe molding, pipe inside diameter, pipe holder, and pipe alignment control. Some materials have been tested as raw materials for outer diameter of pipes, such as wood, iron / steel, cement, and thermoset. The best results are obtained on thermoset material, where the process of disassembling is easier and the resulting mold weight is relatively lighter. For the inside diameter of the pipe is used stainless steel, because in addition to be resistant to chemical processes that occur, in this part of the mold must hold the press load due to shrinkage of raw materials of the pipe during the process of hardening (polymerization). Therefore, it needs high pressure resistant material and does not blend with the raw material of the pipe. The base of the mold is made of stainless steel material because it must be resistant to corrosion due to chemical processes. As for the adjustment of the pipe is made of ST 37 carbon steel, because its function is only as a regulator of the alignment of the pipe structure.

  3. Extraction from TEV-range accelerators using bent crystal channeling

    International Nuclear Information System (INIS)

    Carrigan, R.A. Jr.; Jackson, G.; Murphy, C.T.; Newberger, B.

    1993-01-01

    Plans and first results from Fermilab Experiment 853 are presented. E853 is an experiment to test the feasibility and efficiency of extracting a low-intensity beam from the halo of the Tevatron using channeling in a bent silicon crystal. The motivation of the experiment is to apply crystal extraction to trans-TeV accelerators like the SSC. Channeling developments related to crystal extraction and some early results from accelerator studies at the Tevatron are presented

  4. Double bent crystal dispersive arrangement for high resolution diffractometry

    Czech Academy of Sciences Publication Activity Database

    Mikula, Pavol; Vrána, Miroslav; Šaroun, Jan; Em, V.; Seong, B. S.; Woo, W.

    2012-01-01

    Roč. 340, 012014 (2012), s. 1-6 ISSN 1742-6588. [5th European Conference on Neutron Scattering. Praha, 17.07.2011-21.07.2011] R&D Projects: GA ČR GAP204/10/0654; GA AV ČR KJB100480901 EU Projects: European Commission(XE) 226507 - NMI3 Institutional support: RVO:61389005 Keywords : neutron diffraction * double bent Subject RIV: BG - Nuclear, Atomic and Molecular Physics , Colliders

  5. Beam-smiling in bent-Laue monochromators

    International Nuclear Information System (INIS)

    Ren, B.; Dilmanian, F.A.; Wu, X.Y.; Huang, X.; Ivanov, I.; Thomlinson, W.C.

    1997-01-01

    When a wide fan-shaped x-ray beam is diffracted by a bent crystal in the Laue geometry, the profile of the diffracted beam generally does not appear as a straight line, but as a line with its ends curved up or curved down. This effect, referred to as ' beam-smiling', has been a major obstacle in developing bent-Laue crystal monochromators for medical applications of synchrotron x-ray. We modeled a cylindrically bent crystal using the Finite Element Analysis (FEA) method, and we carried out experiments at the National Synchrotron Light Source and Cornell High Energy Synchrotron Source. Our studies show that, while beam-smiling exists in most of the crystal close-quote s area because of anticlastic bending effects, there is a region parallel to the bending axis of the crystal where the diffracted beam is ' smile-free'. By applying asymmetrical bending, this smile-free region can be shifted vertically away from the geometric center of the crystal, as desired. This leads to a novel method of compensating for beam-smiling. We will discuss the method of ' differential bending' for smile removal, beam-smiling in the Cauchios and the polychromatic geometry, and the implications of the method on developing single- and double-bent Laue monochromators. The experimental results will be discussed, concentrating on specific beam-smiling observation and removal as applied to the new monochromator of the Multiple Energy Computed Tomography [MECT] project of the Medical Department, Brookhaven National Laboratory. copyright 1997 American Institute of Physics

  6. Bent versus straight tips in micropulsed longitudinal phacoemulsification.

    Science.gov (United States)

    Stagg, Brian C; Gupta, Isha; Cahoon, Judd; Ronquillo, Cecinio; Shi, Dallas; Zaugg, Brian; Gardiner, Gareth; Barlow, William R; Pettey, Jeff H; Aabid Farukhi, M; Jensen, Jason; Olson, Randall J

    2015-10-01

    The aim of this study was to evaluate bent and straight phacoemulsification tips to determine which tip is more efficient in removal of lens fragments, using micropulsed longitudinal ultrasound in phacoemulsification. In vitro laboratory study. The John A. Moran Eye Center Laboratories, University of Utah, Salt Lake City, Utah, was the study setting. Pig lenses hardened in a manner comparable with dense human cataracts were cut into 2-mm cubes and removed with micropulsed longitudinal ultrasound using settings previously shown to be optimally efficient (6 milliseconds on and 6 milliseconds off for a bent tip). To verify this time as most efficient for a straight tip, we also tested times of 5, 6, and 7 milliseconds time on and off. The tips were either straight or with a 20-degree bend. Twenty cubes were used for each comparative run. For the straight tip, 6 milliseconds on (1.56 ± 0.815 seconds) was significantly more efficient than 7 milliseconds on (2.45 ± 1.56 seconds, p = 0.001) and not significantly more efficient than 5 milliseconds on (1.69 ± 0.86 seconds, p = 0.43). Five milliseconds off time (1.45 ± 0.76s) was more efficient than 6 milliseconds (2.06 ± 1.37 seconds, p = 0.004) and 7 milliseconds off (2.18 ± 1.24s, p = 0.001). The straight tip was more efficient than the bent tip (1.38 ± 0.83 versus 2.93 ± 2.14 seconds, p = 0.006). Results are contrary to accepted common belief. Micropulsed longitudinal phacoemulsification is more efficient with a straight rather than a bent tip. Copyright © 2015 Canadian Ophthalmological Society. Published by Elsevier Inc. All rights reserved.

  7. Probing strain in bent semiconductor nanowires with Raman spectroscopy.

    Science.gov (United States)

    Chen, Jianing; Conache, Gabriela; Pistol, Mats-Erik; Gray, Struan M; Borgström, Magnus T; Xu, Hongxing; Xu, H Q; Samuelson, Lars; Håkanson, Ulf

    2010-04-14

    We present a noninvasive optical method to determine the local strain in individual semiconductor nanowires. InP nanowires were intentionally bent with an atomic force microscope and variations in the optical phonon frequency along the wires were mapped using Raman spectroscopy. Sections of the nanowires with a high curvature showed significantly broadened phonon lines. These observations together with deformation potential theory show that compressive and tensile strain inside the nanowires is the physical origin of the observed phonon energy variations.

  8. Non-symmetrical bent-shaped compounds containing chiral moiety

    Czech Academy of Sciences Publication Activity Database

    Novotná, Vladimíra; Mieczkowska, B.; Hamplová, Věra; Domján, A.; Pociecha, D.; Kašpar, Miroslav; Fodor-Csorba, K.

    2012-01-01

    Roč. 39, č. 10 (2012), s. 1252-1260 ISSN 0267-8292 R&D Projects: GA ČR(CZ) GAP204/11/0723 Institutional research plan: CEZ:AV0Z10100520 Keywords : bent-shaped mesogen * columnar phase * ferroelectricity * polar switching Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.959, year: 2012 http://www.tandfonline.com/doi/abs/10.1080/02678292.2012.714485

  9. Waste pipe calculus extensions

    International Nuclear Information System (INIS)

    O'Connell, W.J.

    1979-01-01

    The waste pipe calculus provides a rapid method, using Laplace transforms, to calculate the transport of a pollutant such as nuclear waste, by a network of one-dimensional flow paths. The present note extends previous work as follows: (1) It provides an alternate approximation to the time-domain function (inverse Laplace transform) for the resulting transport. This algebraic approximation may be viewed as a simpler and more approximate model of the transport process. (2) It identifies two scalar quantities which may be used as summary consequence measures of the waste transport (or inversely, waste retention) system, and provides algebraic expressions for them. (3) It includes the effects of radioactive decay on the scalar quantity results, and further provides simplifying approximations for the cases of medium and long half-lives. This algebraic method can be used for quick approximate analyses of expected results, uncertainty and sensitivity, in evaluating selection and design choices for nuclear waste disposal systems

  10. Vacuum pipe for e+e- interactions

    International Nuclear Information System (INIS)

    Hoard, C.T.

    1982-10-01

    The design, fabrication and testing of the beryllium vacuum chamber within the Mark II detector at SLAC is described. The Be chamber encloses one interaction point of the PEP circulating ring and is a part of its beam pipe. The Be chamber is captured within the Secondary Vertex Detector (SVD), a drift chamber, which is in turn centered in the Mark II drift chamber. Both ends of the beryllium pipe are brazed to aluminum/stainless transitions for connection to stainless steel bellows. A concentric radiation-screen liner of titanium foil runs the full length of the beryllium pipe

  11. Pipe crawlers: Versatile adaptations for real applications

    Energy Technology Data Exchange (ETDEWEB)

    Hapstack, M.; Talarek, T.R.

    1990-01-01

    A problem at the Savannah River Site requires the unique application of a pipe crawler. A number of stainless steel pipes buried in concrete require ultrasonic inspection of the heat affected zones of the welds for detection of flaws or cracks. The paper describes the utilization of an inch-worm motion pipe crawler which negotiates a 90 degree reducing elbow with significant changes in diameter and vertical sections before entering the area of concern. After a discussion of general considerations and problem description, special requirements to meet the objectives and the design approach regarding the tractor, control system, instrument carriage, and radiation protection are discussed. 2 refs., 11 figs. (MB)

  12. Update of foundation design modifications of data cables and piping in nuclear power plants in operation; Actualizacion de modificaciones de sieno de bases de datos de cables y conducciones en centrales nucleares en operacion

    Energy Technology Data Exchange (ETDEWEB)

    Perez Pereira, J.

    2013-07-01

    The scope of this application is the manage the life cycle of cables electrical and pipes of cables in Trillo NPP. The application is integrated in a configuration Control system, so both cables and conduits become elements of configuration and management of life and history associated with the of the relevant modifying documents. The guarantees criteria of physical separation of wires for jobs and for independent networks designed according to the redundancy of the Central System.

  13. Structural and stress analysis of nuclear piping systems

    International Nuclear Information System (INIS)

    Hata, Hiromichi

    1982-01-01

    The design of the strength of piping system is important in plant design, and its outline on the example of PWRs is reported. The standards and guides concerning the design of the strength of piping system are shown. The design condition for the strength of piping system is determined by considering the requirements in the normal operation of plants and for the safety design of plants, and the loads in normal operation, testing, credible accident and natural environment are explained. The methods of analysis for piping system are related to the transient phenomena of fluid, piping structure and local heat conduction, and linear static analysis, linear time response analysis, nonlinear time response analysis, thermal stress analysis and fluid transient phenomenon analysis are carried out. In the aseismatic design of piping system, it is desirable to avoid the vibration together with a building supporting it, and as a rule, to make it into rigid structure. The piping system is classified into high temperature and low temperature pipings. The formulas for calculating stress and the allowable condition, the points to which attention must be paid in the design of piping strength and the matters to be investigated hereafter are described. (Kako, I.)

  14. Piping engineering and operation

    International Nuclear Information System (INIS)

    1993-01-01

    The conference 'Piping Engineering and Operation' was organized by the Institution of Mechanical Engineers in November/December 1993 to follow on from similar successful events of 1985 and 1989, which were attended by representatives from all sectors of the piping industry. Development of engineering and operation of piping systems in all aspects, including non-metallic materials, are highlighted. The range of issues covered represents a balance between current practices and implementation of future international standards. Twenty papers are printed. Two, which are concerned with pressurized pipes or steam lines in the nuclear industry, are indexed separately. (Author)

  15. Nanostructures of liquid crystal phases in mixtures of bent-core and rod-shaped molecules

    International Nuclear Information System (INIS)

    Hong, S. H.; Gleeson, J. T.; Sprunt, S.; Verduzco, R.; Jakli, A.

    2011-01-01

    We report small angle x-ray scattering (SAXS) studies of isotropic, nematic, and smectic mesophases formed by binary mixtures of bent-core (BC) and rod-shaped (RS) molecules. While optical studies indicate that the components are fully miscible, SAXS reveals fascinating structures that are consistent with segregation on a nanoscopic scale. We find that tilted smectic clusters, which have been previously reported in both the nematic and isotropic states of the pure BC materials, are also present in mixtures with up to 50 wt% of the RS compound; this is consistent with previous dielectric and flexoelectric studies on such mixtures. Unexpectedly in this concentration range the clusters are present in the isotropic and in the induced smectic phase range, as well as throughout the nematic phase. The results in the smectic phase also reveal complex layering phenomena, providing important insight into the interaction between bent and rod-shaped molecules. These studies will be crucial in the design of promising new functional nanomaterials.

  16. Hot Leg Piping Materials Issues

    International Nuclear Information System (INIS)

    V. Munne

    2006-01-01

    With Naval Reactors (NR) approval of the Naval Reactors Prime Contractor Team (NRPCT) recommendation to develop a gas cooled reactor directly coupled to a Brayton power conversion system as the space nuclear power plant (SNPP) for Project Prometheus (References a and b) the reactor outlet piping was recognized to require a design that utilizes internal insulation (Reference c). The initial pipe design suggested ceramic fiber blanket as the insulation material based on requirements associated with service temperature capability within the expected range, very low thermal conductivity, and low density. Nevertheless, it was not considered to be well suited for internal insulation use because its very high surface area and proclivity for holding adsorbed gases, especially water, would make outgassing a source of contaminant gases in the He-Xe working fluid. Additionally, ceramic fiber blanket insulating materials become very friable after relatively short service periods at working temperatures and small pieces of fiber could be dislodged and contaminate the system. Consequently, alternative insulation materials were sought that would have comparable thermal properties and density but superior structural integrity and greatly reduced outgassing. This letter provides technical information regarding insulation and materials issues for the Hot Leg Piping preconceptual design developed for the Project Prometheus space nuclear power plant (SNPP)

  17. International piping integrity research group (IPIRG) program final report

    International Nuclear Information System (INIS)

    Schmidt, R.; Wilkowski, G.; Scott, P.; Olsen, R.; Marschall, C.; Vieth, P.; Paul, D.

    1992-04-01

    This is the final report of the International Piping Integrity Research Group (IPIRG) Programme. The IPIRG Programme was an international group programme managed by the U.S. Nuclear Regulatory Commission and funded by a consortium of organizations from nine nations: Canada, France, Italy, Japan, Sweden, Switzerland, Taiwan, the United Kingdom, and the United states. The objective of the programme was to develop data needed to verify engineering methods for assessing the integrity of nuclear power plant piping that contains circumferential defects. The primary focus was an experimental task that investigated the behaviour of circumferentially flawed piping and piping systems to high-rate loading typical of seismic events. To accomplish these objectives a unique pipe loop test facility was designed and constructed. The pipe system was an expansion loop with over 30 m of 406-mm diameter pipe and five long radius elbows. Five experiments on flawed piping were conducted to failure in this facility with dynamic excitation. The report: provides background information on leak-before-break and flaw evaluation procedures in piping; summarizes the technical results of the programme; gives a relatively detailed assessment of the results from the various pipe fracture experiments and complementary analyses; and, summarizes the advances in the state-of-the-art of pipe fracture technology resulting from the IPIRG Program

  18. Comparison and evaluation of flexible and stiff piping systems

    International Nuclear Information System (INIS)

    Hahn, W.; Tang, H.T.; Tang, Y.K.

    1983-01-01

    An experimental and numerical study was performed on a piping system, with various support configurations, to assess the difference in piping response for flexible and stiff piping systems. Questions have arisen concerning a basic design philosophy employed in present day piping designs. One basic question is, the reliability of a flexible piping system greater than that of a stiff piping system by virtue of the fact that a flexible system has fewer snubber supports. With fewer snubbers, the pipe is less susceptible to inadvertent thermal stresses introduced by snubber malfunction during normal operation. In addition to the technical issue, the matter of cost savings in flexible piping system design is a significant one. The costs associated with construction, in-service inspection and maintenance are all significantly reduced by reducing the number of snubber supports. The evaluation study, sponsored by the Electric Power Research Institute, was performed on a boiler feedwater line at Consolidated Edison's Indian Point Unit 1. In this study, the boiler feedwater line was tested and analyzed with two fundamentally different support systems. The first system was very flexible, employing rod and spring hangers, and represented the 'old' design philosophy. The pipe system was very flexible with this support system, due to the long pipe span lengths between supports and the fact that there was only one lateral support. This support did not provide much restraint since it was near an anchor. The second system employed strut and snubber supports and represented the 'modern' design philosophy. The pipe system was relatively stiff with this support system, primarily due to the increased number of supports, including lateral supports, thereby reducing the pipe span lengths between supports. The second support system was designed with removable supports to facilitate interchange of the supports with different support types (i.e., struts, mechanical snubbers and hydraulic

  19. Transients in pipes

    International Nuclear Information System (INIS)

    Marchesin, D.; Paes-Leme, P.J.S.; Sampaio, R.

    1981-01-01

    The motion of a fluid in a pipe is commonly modeled utilizing the one space dimension conservation laws of mass and momentum. The development of shocks and spikes utilizing the uniform sampling method is studied. The effects of temperature variations and friction are compared for gas pipes. (Author) [pt

  20. Oscillating heat pipes

    CERN Document Server

    Ma, Hongbin

    2015-01-01

    This book presents the fundamental fluid flow and heat transfer principles occurring in oscillating heat pipes and also provides updated developments and recent innovations in research and applications of heat pipes. Starting with fundamental presentation of heat pipes, the focus is on oscillating motions and its heat transfer enhancement in a two-phase heat transfer system. The book covers thermodynamic analysis, interfacial phenomenon, thin film evaporation,  theoretical models of oscillating motion and heat transfer of single phase and two-phase flows, primary  factors affecting oscillating motions and heat transfer,  neutron imaging study of oscillating motions in an oscillating heat pipes, and nanofluid’s effect on the heat transfer performance in oscillating heat pipes.  The importance of thermally-excited oscillating motion combined with phase change heat transfer to a wide variety of applications is emphasized. This book is an essential resource and learning tool for senior undergraduate, gradua...

  1. Riot at the calc exam and other mathematically bent stories

    CERN Document Server

    Adams, Colin

    2009-01-01

    What's so funny about math? Lots! Especially if you're mathematically bent. In the world of Colin Adams, differential equations bring on tears of laughter. Hollywood producers hire algebraic geometers to punch up a script. In this world, math and humor are synonymous. Riot at the Calc Exam is a proof of this fact. A collection of humorous math stories, this book gives a window into mathematics and the culture of mathematicians. Appropriate for mathematicians, math students, math teachers, lay people with an interest in mathematics, and indeed everyone else. This book is a romp through the wild

  2. Robotic platform for traveling on vertical piping network

    Science.gov (United States)

    Nance, Thomas A; Vrettos, Nick J; Krementz, Daniel; Marzolf, Athneal D

    2015-02-03

    This invention relates generally to robotic systems and is specifically designed for a robotic system that can navigate vertical pipes within a waste tank or similar environment. The robotic system allows a process for sampling, cleaning, inspecting and removing waste around vertical pipes by supplying a robotic platform that uses the vertical pipes to support and navigate the platform above waste material contained in the tank.

  3. Fabrication and evaluation of chemically vapor deposited tungsten heat pipe.

    Science.gov (United States)

    Bacigalupi, R. J.

    1972-01-01

    A network of lithium-filled tungsten heat pipes is being considered as a method of heat extraction from high temperature nuclear reactors. The need for material purity and shape versatility in these applications dictates the use of chemically vapor deposited (CVD) tungsten. Adaptability of CVD tungsten to complex heat pipe designs is shown. Deposition and welding techniques are described. Operation of two lithium-filled CVD tungsten heat pipes above 1800 K is discussed.

  4. High energy beam line based on bent crystal

    International Nuclear Information System (INIS)

    Biryukov, V.M.; Chesnokov, Yu.A.; Greth, V.N.; Ivanov, A.A.; Kotov, V.I.; Selesnev, V.S.; Tarakanov, M.V.; Terekhov, V.I.; Tsarik, S.V.

    1995-01-01

    A peculiarities of the beam bent with crystals is the independence of the crystal deflector strength Θ=L D /R c ∼0.5 rad of the particle energy (L D is the dechanneling length, R c is the critical radius). The possibility of abrupt bending with crystal of a beam fraction at a large angle allows one to make over a short base a non-traditional beam line to carry out physical experiments. At IHEP, a 150 mrad bent crystal was used to create a test area, to work in parallel with other set-ups consuming practically no power. A 100 mm long Si crystal, placed in the halo of the intense extracted 70 GeV/c beam, extracts along the ∼20 m base 10 6 protons/sec beyond the 2-meter iron-concrete shield. The beam high quality (low emittance and high stability) allows one to carry out the program of the studies of channeling and testing the microstrip detectors. 2 refs.; 2 figs

  5. Numerical Prediction of Springback Shape of Severely Bent Sheet Metal

    International Nuclear Information System (INIS)

    Iwata, Noritoshi; Murata, Atsunobu; Yogo, Yasuhiro; Tsutamori, Hideo; Niihara, Masatomo; Ishikura, Hiroshi; Umezu, Yasuyoshi

    2007-01-01

    In the sheet metal forming simulation, the shell element widely used is assumed as a plane stress state based on the Mindlin-Reissner theory. Numerical prediction with the conventional shell element is not accurate when the bending radius is small compared to the sheet thickness. The main reason is because the strain and stress formulation of the conventional shell element does not fit the actual phenomenon. In order to predict precisely the springback of a bent sheet with a severe bend, a measurement method for through-thickness strain has been proposed. The strain was formulated based on measurement results and calculation results from solid element. Through-thickness stress distribution was formulated based on the equilibrium. The proposed shell element based on the formulations was newly introduced into the FEM code. The accuracy of this method's prediction of the springback shape of two bent processes has been confirmed. As a result, it was found that the springback shape even in severe bending can be predicted with high accuracy. Moreover, the calculation time in the proposed shell element is about twice that in the conventional shell element, and has been shortened to about 1/20 compared to a solid element

  6. Improved Thin, Flexible Heat Pipes

    Science.gov (United States)

    Rosenfeld, John H.; Gernert, Nelson J.; Sarraf, David B.; Wollen, Peter J.; Surina, Frank C.; Fale, John E.

    2004-01-01

    Flexible heat pipes of an improved type are fabricated as layers of different materials laminated together into vacuum- tight sheets or tapes. In comparison with prior flexible heat pipes, these flexible heat pipes are less susceptible to leakage. Other advantages of these flexible heat pipes, relative to prior flexible heat pipes, include high reliability and greater ease and lower cost of fabrication. Because these heat pipes are very thin, they are highly flexible. When coated on outside surfaces with adhesives, these flexible heat pipes can be applied, like common adhesive tapes, to the surfaces of heat sinks and objects to be cooled, even if those surfaces are curved.

  7. Heat pipes with variable thermal conductance property for space applications

    Energy Technology Data Exchange (ETDEWEB)

    Kravets, V.; Alekseik, Ye.; Alekseik, O.; Khairnasov, S. [National Technical University of Ukraine, Kyiv (Ukraine); Baturkin, V.; Ho, T. [Explorationssysteme RY-ES, Bremen (Germany); Celotti, L. [Active Space Technologies GmbH, Berlin (Germany)

    2017-06-15

    The activities presented in this paper demonstrate a new approach to provide passive thermal control using heat pipes, as demonstrated on the electronic unit of DLR’s MASCOT lander, which embarked on the NEA sample return mission Hayabusa 2 (JAXA). The focus is on the development and testing of heat pipes with variable thermal conductance in a predetermined temperature range. These heat pipes act as thermal switches. Unlike standard gasloaded heat pipes and thermal-diode heat pipes construction of presented heat pipes does not include any additional elements. Copper heat pipes with metal fibrous wicks were chosen as baseline design. We obtained positive results by choosing the heat carrier and structural parameters of the wick (i.e., pore diameter, porosity, and permeability). The increase in the thermal conductivity of the heat pipes from 0.04 W/K to 2.1 W/K was observed in the temperature range between −20 °C and +55 °C. Moreover, the heat pipes transferred the predetermined power of not less than 10 W within the same temperature range. The heat pipes have been in flight since December 2014, and the supporting telemetry data were obtained in September 2015. The data showed the nominal operation of the thermal control system.

  8. Nonlinear dynamic analysis of high energy line pipe whip

    International Nuclear Information System (INIS)

    Hsu, L.C.; Kuo, A.Y.; Tang, H.T.

    1983-01-01

    To facilitate potential cost savings in pipe whip protection design, TVA conducted a 1'' high pressure line break test to investigate the pipe whip behavior. The test results are available to EPRI as a data base for a generic study on nonlinear dynamic behavior of piping systems and pipe whip phenomena. This paper describes a nonlinear dynamic analysis of the TVA high energy line tests using ABAQUS-EPGEN code. The analysis considers the effects of large deformation and high strain rate on resisting moment and energy absorption capability of the analyzed piping system. The numerical results of impact forces, impact velocities, and reaction forces at pipe supports are compared to the TVA test data. The pipe whip impact time and forces have also been calculated per the current NRC guidelines and compared. The calculated pipe support reaction forces prior to impact have been found to be in good agreement with the TVA test data except for some peak values at the very beginning of the pipe break. These peaks are believed to be due to stress wave propagation which cannot be addressed by the ABAQUS code. Both the effects of elbow crushing and strain rate have been approximately simulated. The results are found to be important on pipe whip impact evaluation. (orig.)

  9. Analysis of a piping system for requalification

    International Nuclear Information System (INIS)

    Hsieh, B.J.; Tang, Yu.

    1992-01-01

    This paper discusses the global stress analysis required for the seismic/structural requalification of a reactor secondary piping system in which minor defects (flaws) were discovered during a detailed inspection. The flaws in question consisted of weld imperfections. Specifically, it was necessary to establish that the stresses at the flawed sections did not exceed the allowables and that the fatigue life remained within acceptable limits. At the same time the piping system had to be qualified for higher earthquake loads than those used in the original design. To accomplish these objectives the nominal stress distributions in the piping system under the various loads (dead load, thermal load, wind load and seismic load) were determined. First a best estimate finite element model was developed and calculations were performed using the piping analysis modules of the ANSYS Computer Code. Parameter studies were then performed to assess the effect of physically reasonable variations in material, structural, and boundary condition characteristics. The nominal stresses and forces so determined, provided input for more detailed analyses of the flawed sections. Based on the reevaluation, the piping flaws were judged to be benign, i.e., the piping safety margins were acceptable inspite of the increased seismic demand. 13 refs

  10. Microstructural characterization of pipe bomb fragments

    International Nuclear Information System (INIS)

    Gregory, Otto; Oxley, Jimmie; Smith, James; Platek, Michael; Ghonem, Hamouda; Bernier, Evan; Downey, Markus; Cumminskey, Christopher

    2010-01-01

    Recovered pipe bomb fragments, exploded under controlled conditions, have been characterized using scanning electron microscopy, optical microscopy and microhardness. Specifically, this paper examines the microstructural changes in plain carbon-steel fragments collected after the controlled explosion of galvanized, schedule 40, continuously welded, steel pipes filled with various smokeless powders. A number of microstructural changes were observed in the recovered pipe fragments: deformation of the soft alpha-ferrite grains, deformation of pearlite colonies, twin formation, bands of distorted pearlite colonies, slip bands, and cross-slip bands. These microstructural changes were correlated with the relative energy of the smokeless powder fillers. The energy of the smokeless powder was reflected in a reduction in thickness of the pipe fragments (due to plastic strain prior to fracture) and an increase in microhardness. Moreover, within fragments from a single pipe, there was a radial variation in microhardness, with the microhardness at the outer wall being greater than that at the inner wall. These findings were consistent with the premise that, with the high energy fillers, extensive plastic deformation and wall thinning occurred prior to pipe fracture. Ultimately, the information collected from this investigation will be used to develop a database, where the fragment microstructure and microhardness will be correlated with type of explosive filler and bomb design. Some analyses, specifically wall thinning and microhardness, may aid in field characterization of explosive devices.

  11. Margins for an in-plant piping system under dynamic loading

    International Nuclear Information System (INIS)

    Kot, C.A.; Srinivasan, M.G.; Hsieh, B.J.

    1991-01-01

    The objective of this study is to verify that piping designed according to current practice does indeed have a large margin against failure and to quantify the excess capacity for piping and dynamic pipe supports on the basis of data obtained in a series of high-level seismic experiments (designated SHAM) on an in-plant piping system at the HDR (Heissdampfreaktor) Test Facility in Germany. 4 refs., 6 tabs

  12. The pipes of pan.

    Science.gov (United States)

    Chalif, David J

    2004-12-01

    The pipes of pan is the crowning achievement of Pablo Picasso's neoclassical period of the 1920s. This monumental canvas depicts a mythological Mediterranean scene in which two sculpted classical giants stare out, seemingly across the centuries, toward a distant and lost Arcadia. Picasso was influenced by Greco-Roman art during his travels in Italy, and his neoclassical works typically portray massive, immobile, and pensive figures. Pan and his pipes are taken directly from Greek mythological lore by Picasso and placed directly into 20th century art. He frequently turned to various mythological figures throughout his metamorphosing periods. The Pipes of Pan was also influenced by the painter's infatuation with the beautiful American expatriate Sara Murphy, and the finished masterpiece represents a revision of a previously conceived neoclassical work. The Pipes of Pan now hangs in the Musee Picasso in Paris.

  13. Heat Pipe Systems

    Science.gov (United States)

    1993-01-01

    The heat pipe was developed to alternately cool and heat without using energy or any moving parts. It enables non-rotating spacecraft to maintain a constant temperature when the surface exposed to the Sun is excessively hot and the non Sun-facing side is very cold. Several organizations, such as Tropic-Kool Engineering Corporation, joined NASA in a subsequent program to refine and commercialize the technology. Heat pipes have been installed in fast food restaurants in areas where humid conditions cause materials to deteriorate quickly. Moisture removal was increased by 30 percent in a Clearwater, FL Burger King after heat pipes were installed. Relative humidity and power consumption were also reduced significantly. Similar results were recorded by Taco Bell, which now specifies heat pipe systems in new restaurants in the Southeast.

  14. Development of intelligent pipe locator

    Science.gov (United States)

    Miyamoto, Y.; Wasa, Y.

    1986-08-01

    An inductive pipe locator was developed, so that the position and depth of an underground gas pipe can be accurately located by passing an ac current to the pipe and measuring the generated magnetic field. An ac current (several to 100 kHz) of several tens of mA is transmitted to the underground pipe, and a magnetic sensor above the ground catches the induced magnetic field to estimate the position and depth of the pipe.

  15. Technology transfer: taking science from the books to the ground at Bent Creek Experimental Forest

    Science.gov (United States)

    Julia Kirschman

    2014-01-01

    Technology transfer has been an important part of the research program at Bent Creek Experimental Forest (Bent Creek) since its establishment in 1925. Our stated mission is to develop and disseminate knowledge and strategies for restoring, managing, sustaining, and enhancing the vegetation and wildlife of upland hardwood-dominated forest ecosystems of the Southern...

  16. Stuck pipe prediction

    KAUST Repository

    Alzahrani, Majed

    2016-03-10

    Disclosed are various embodiments for a prediction application to predict a stuck pipe. A linear regression model is generated from hook load readings at corresponding bit depths. A current hook load reading at a current bit depth is compared with a normal hook load reading from the linear regression model. A current hook load greater than a normal hook load for a given bit depth indicates the likelihood of a stuck pipe.

  17. Application of LBB to a nozzle-pipe interface

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Y.J.; Sohn, G.H.; Kim, Y.J. [and others

    1997-04-01

    Typical LBB (Leak-Before-Break) analysis is performed for the highest stress location for each different type of material in the high energy pipe line. In most cases, the highest stress occurs at the nozzle and pipe interface location at the terminal end. The standard finite element analysis approach to calculate J-Integral values at the crack tip utilizes symmetry conditions when modeling near the nozzle as well as away from the nozzle region to minimize the model size and simplify the calculation of J-integral values at the crack tip. A factor of two is typically applied to the J-integral value to account for symmetric conditions. This simplified analysis can lead to conservative results especially for small diameter pipes where the asymmetry of the nozzle-pipe interface is ignored. The stiffness of the residual piping system and non-symmetries of geometry along with different material for the nozzle, safe end and pipe are usually omitted in current LBB methodology. In this paper, the effects of non-symmetries due to geometry and material at the pipe-nozzle interface are presented. Various LBB analyses are performed for a small diameter piping system to evaluate the effect a nozzle has on the J-integral calculation, crack opening area and crack stability. In addition, material differences between the nozzle and pipe are evaluated. Comparison is made between a pipe model and a nozzle-pipe interface model, and a LBB PED (Piping Evaluation Diagram) curve is developed to summarize the results for use by piping designers.

  18. Influence of plastic deformation on seismic response of piping

    International Nuclear Information System (INIS)

    Yao Yanping; Chen Yong; Lu Mingwan

    2000-01-01

    On the basis of a brief summary of linear elastic seismic analysis methods, the importance for consideration of plastic deformation during the dynamic response analysis of piping system is indicated. The present methods of considering plasticity and the disadvantages of these methods are discussed. And the authors point out that in order to reduce the conservatism of present codes and to put forward appropriate and realistic piping seismic design methods, the key is to understand the plastic dynamic failure mode for piping under seismic excitation and to calculate the inelastic energy dissipation. The analysis and evaluation are applicable to nuclear piping systems

  19. Magnetic-Force-Assisted Straightening of Bent Mild Steel Strip by Laser Irradiation

    Science.gov (United States)

    Dutta, Polash P.; Kalita, Karuna; Dixit, Uday S.; Liao, Hengcheng

    2017-12-01

    This study proposes a technique to straighten bent metallic strips with magnetic-force-assisted laser irradiation. Experiments were conducted for three different types of mechanically-bent mild strips. The first type was bent strips without any heat treatment. The second type was stress-relieved and third type was subcritical-annealed bent strips. These strips were straightened following different schemes of laser irradiation sequence to understand the performance of straightening. A parametric study was conducted by varying laser power and scanning speed. Micro-hardness, tensile test, Charpy impact test and microstructure after straightening were also studied. Different scanning schemes provided different microstructures and mechanical properties. Any serious deterioration in the quality of straightened strips was not noticed. Overall, subcritical-annealed bent strips provided the best performance in straightening. The proposed straightening scheme has potential of becoming an industrial practice.

  20. Field investigation on structural performance of the buried UPVC pipes with and without geogrid reinforcement

    Science.gov (United States)

    Teja, Akkineni Surya; Rajkumar, R.; Gokula Krishnan, B.; Aravindh, R.

    2018-02-01

    Buried pipes are used mainly for water supply and drainage besides many other applications such as oil, liquefied natural gas, coal slurries and mine tailings. The pipes used may be rigid (reinforced concrete, vitrified clay and ductile iron) or flexible (Steel, UPVC, aluminium, Fiber glass and High-density polyethylene) although the distinction between them is blurring. Flexible pipe design is governed by deflection or buckling. UPVC pipes are preferred due to light weight, long term chemical stability and cost efficiency. This project aims to study the load deformation behaviour of the buried pipe and stress variation across the cross section of the pipe under static loading along with the influence of depth of embedment, density of backfill on the deformation and stresses in pipe and the deformation behaviour of buried pipe when soil is reinforced with geogrid reinforcement and evaluate the structural performance of the pipe.

  1. Development of nonlinear dynamic analysis program for nuclear piping systems

    International Nuclear Information System (INIS)

    Kamichika, Ryoichi; Izawa, Masahiro; Yamadera, Masao

    1980-01-01

    In the design for nuclear power piping, pipe-whip protection shall be considered in order to keep the function of safety related system even when postulated piping rupture occurs. This guideline was shown in U.S. Regulatory Guide 1.46 for the first time and has been applied in Japanese nuclear power plants. In order to analyze the dynamic behavior followed by pipe rupture, nonlinear analysis is required for the piping system including restraints which play the role of an energy absorber. REAPPS (Rupture Effective Analysis of Piping Systems) has been developed for this purpose. This program can be applied to general piping systems having branches etc. Pre- and post- processors are prepared in this program in order to easily input the data for the piping engineer and show the results optically by use of a graphic display respectively. The piping designer can easily solve many problems in his daily work by use of this program. This paper describes about the theoretical background and functions of this program and shows some examples. (author)

  2. Bent Telescopic Rods in Patients With Osteogenesis Imperfecta.

    Science.gov (United States)

    Lee, R Jay; Paloski, Michael D; Sponseller, Paul D; Leet, Arabella I

    2016-09-01

    Telescopic rods require alignment of 2 rods to enable lengthening. A telescopic rod converts functionally into a solid rod if either rod bends, preventing proper engagement. Our goal was to characterize implant bending as a mode of failure of telescopic rods used in the treatment of osteogenesis imperfecta in children. We conducted a retrospective review of our osteogenesis imperfecta database for patients treated with intramedullary telescopic rods at our institution from 1992 through 2010 and identified 12 patients with bent rods. The 6 boys and 6 girls had an average age at the time of initial surgery of 3.1 years (range, 1.8 to 8.3 y) and a total of 51 telescoping rods. Clinic notes, operative reports, and radiographs were reviewed. The rods were analyzed for amount of lengthening, characteristics of bending, presence of cut out, or disengagement from an anchor point. Bends in the rods were characterized by their location on the implant component. The bent and straight rods were compared. Data were analyzed with the Mann-Whitney test (statistical significance set at P≤0.05). Of the 51 telescoping rods, 17 constructs (33%) bent. The average interval between surgery and rod bending was 4.0 years (range, 0.9 to 8.2 y). Before bending, 11 of 17 telescoping rods had routine follow-up radiographs for review. In 10 of the rods, bending was present when early signs of rod failure were first detected. Rod bending did not seem to be related to rod size. There was no area on the rod itself that seemed more susceptible to bending. Rod bending can be an early sign of impending rod failure. When rod bending is first noted, it may predispose the rod to other subsequent failures such as loss of proximal and distal fixation and cut out. Rod bending should be viewed as an indicator for closer monitoring of the patient and discussions regarding future need for rod exchange. Level III-retrospective review.

  3. A parametric study of porous wick in heat pipe

    International Nuclear Information System (INIS)

    Park, Yong Jin; Jun, Sang Ook; Jung, Ji Hun; Kim, Jeong Hwa; Lee, Dong Ho

    2008-01-01

    A Heat pipe which acquires a power by a capillary force has been used to mainly cool heat sources in satellites for long times. Among types of heat pipes, Loop Heat Pipe, Capillary Pumped Loop have usually used porous wicks such as sintered powder and fine wick to circulate a working fluid. These porous wicks have many design variables which affect thermal phenomena such as a capillary driven force, disjoining pressure, drying limitation, boiling limitation, etc. Additionally, Fins connecting an evaporator surface with a porous wick also after thermal characteristics of heat pipe. Especially, a vapor blanket thickness being main variables to decide a wick thickness has to do with fin sizes. Accordingly, understanding design variables' characteristics of porous wicks and fins is important to execute design optimization of heat pipe. In this paper, analytical methods and results will be discussed in terms of parametric study

  4. Temperature stratification in a hot water tank with circulation pipe

    DEFF Research Database (Denmark)

    Andersen, Elsa

    1998-01-01

    The aim of the project is to investigate the change in temperature stratification due to the operation of a circulation pipe. Further, putting forward rules for design of pipe inlet in order not to disturb the temperature stratification in the hot water tank. A validated computer model based...

  5. 33 CFR 157.11 - Pumping, piping and discharge arrangements.

    Science.gov (United States)

    2010-07-01

    ... CARRYING OIL IN BULK Design, Equipment, and Installation § 157.11 Pumping, piping and discharge... of this part. (d) Each tank vessel under § 157.09, § 157.10a, or § 157.10b that carries crude oil... lines for the draining of oil residue from cargo pumps and other oil piping lines to a cargo tank or a...

  6. Characterization of kink actuators as compared to traditional chevron shaped Bent-Beam electrothermal actuators

    KAUST Repository

    Rawashdeh, E.

    2012-07-06

    This paper compares the design and performance of kink actuators, a modified version of the bent-beam thermal actuator, to the standard chevron-shaped designs. A variety of kink and chevron actuator designs were fabricated from polysilicon. While the actuators were electrically probed, these designs were tested using a probe station connected to a National Instruments (NI) controller that uses LabVIEW to extract the displacement results via image processing. The displacement results were then used to validate the thermal-electric-structural simulations produced by COMSOL. These results, in turn, were used to extract the stiffness for both actuator types. The data extracted show that chevron actuators can have larger stiffness values with increasing offsets, but at the cost of lower amplification factors. In contrast, kink actuators showed a constant stiffness value equivalent to the chevron actuator with the highest amplification factor. The kink actuator also had larger amplification factors than chevrons at all designs tested. Therefore, kink actuators are capable of longer throws at lower power levels than the standard chevron designs.

  7. Modified method for registration of particle deflection by bent crystal

    International Nuclear Information System (INIS)

    Afanas'ev, S.V.; Kovalenko, A.D.; Kuznetsov, V.N.; Romanov, S.V.; Sajfulin, Sh.Z.; Taratin, A.M.; Volkov, V.I.; Voevodin, M.A.; Bojko, V.V.

    2003-01-01

    The modified method for registration of particle deflection by a bent crystal was proposed and studied at the external proton beam of the Nuclotron. The telescope of scintillation counters was placed at the angle that was smaller than a crystal bending angle. The count dependence of the telescope on the crystal orientation was formed by the particles, which passed in channeling states only some part of the crystal length. Two maximums were observed in the dependencies due to particles captured into the channeling states on the crystal surface and in the crystal volume. This allows one to obtain, using the telescope and high-intensity beams, useful data about the particle channeling and the crystal, which usually demands more complicated registration by means of the coordinate detectors

  8. Dynamic relaxation method in analysis of reinforced concrete bent elements

    Directory of Open Access Journals (Sweden)

    Anna Szcześniak

    2015-12-01

    Full Text Available The paper presents a method for the analysis of nonlinear behaviour of reinforced concrete bent elements subjected to short-term static load. The considerations in the range of modelling of deformation processes of reinforced concrete element were carried out. The method of structure effort analysis was developed using the finite difference method. The Dynamic Relaxation Method, which — after introduction of critical damping — allows for description of the static behaviour of a structural element, was used to solve the system of nonlinear equilibrium equations. In order to increase the method effectiveness in the range of the post-critical analysis, the Arc Length Parameter on the equilibrium path was introduced into the computational procedure.[b]Keywords[/b]: reinforced concrete elements, physical nonlinearity, geometrical nonlinearity, dynamic relaxation method, arc-length method

  9. EcoRV catalysis with a pre-bent substrate

    Science.gov (United States)

    Sanchez, Daniel S.; Zocchi, Giovanni

    2015-05-01

    Enzymes are deformable molecules which often adapt their conformation to the substrate's geometry. In the case of restriction enzymes acting on DNA, the substrate (DNA) is deformable also. While it is well established that external mechanical stress exerted on an enzyme modulates the enzymatic activity, the effect of mechanically stressing the substrate is less explored. Here we present the restriction enzyme EcoRV with a series of pre-bent DNA substrates and observe modulation of the overall speed of the enzymatic reaction by up to a factor 50. While in all cases the reaction is slowed down compared to the unstressed substrate, we observe peaks in the reaction rate as we vary the state of stress of the DNA substrate. Both bending moments and torsional moments on the DNA substrate affect the reaction rate.

  10. Identification and reduction of piping-vibrations in plants

    International Nuclear Information System (INIS)

    Kerkhof, K.

    2012-01-01

    Safe operation, availability and lifetime assessment of piping systems are of utmost concern for plant operators. The use of tuned mass dampers is a rather new approach for reducing vibrations to avoid high cycle fatigue in a large chemical piping system. The investigated piping system is supported by a tall structure fixed at the base. As a result, the steel building stiffness decreases with height. Furthermore large piping-elbow forces act at the top of the building, which lead to large vibration amplitudes. Since both piping system and supporting structure exhibited these large vibration amplitudes, dampers or shock absorbers placed between them would prove ineffective. Therefore, special vibration absorbers were developed for such piping systems. The paper presents the design process, starting with an extensive system investigation up to the passive multi-axial vibration absorber design parameters. This includes: Laboratory tests with a mock-up pipe system, where the first design ideas for new passive vibration absorbers were investigated. Vibration measurements were carried out to investigate the current state of the vibration behaviour. The piping system was inspected; strain gauges were used to identify stress concentrations at welds and other notches due to ovalization. Finite element calculations were performed, first as a combined beam and shell model for the pipe without the support structure. A detailed model for the combined steel construction and pipe system was created. Model-updating was done to fit the calculated model to the experimental modal analysis data. Loading assumptions describing excitation forces from the mass flow were checked. Harmonic frequency analysis was performed. On the basis of these calculations design parameters for the passive vibration absorber were determined. Finally, a solution for the design of two passive vibration absorbers will be presented.

  11. An optical method for measuring the thickness of a falling condensate in gravity assisted heat pipe

    Directory of Open Access Journals (Sweden)

    Kasanický Martin

    2015-01-01

    Full Text Available A large number of variables is the main problem of designing systems which uses heat pipes, whether it is a traditional - gravity, or advanced - capillary, pulsating, advanced heat pipes. This article is a methodology for measuring the thickness of the falling condensate in gravitational heat pipes, with using the optical triangulation method, and the evaluation of risks associated with this method.

  12. Piping data bank and erection system of Angra 2: structure, computational resources and systems

    International Nuclear Information System (INIS)

    Abud, P.R.; Court, E.G.; Rosette, A.C.

    1992-01-01

    The Piping Data Bank of Angra 2 called - Erection Management System - Was developed to manage the piping erection of the Nuclear Power Plant of Angra 2. Beyond the erection follow-up of piping and supports, it manages: the piping design, the material procurement, the flow of the fabrication documents, testing of welds and material stocks at the Warehouse. The works developed in the sense of defining the structure of the Data Bank, Computational Resources and System are here described. (author)

  13. Investigation on the Behavior of Rigid Polyvinylchloride Pipes Subjected to Uniaxial Compression Loads

    OpenAIRE

    Abdullah A.N. Alhamati; Abdul H. Ghazali; Jamalodin Norzaie; Norzaie A. Mohammed; Mohd R.A. Kadir

    2006-01-01

    The objective of this research was to investigate the capability of rigid Polyvinylchloride (PVC-U) pipes to sustain axial loads. The behavior of PVC-U pipes specimens subjected to short-term uniaxial compression loads was experimentally investigated. Results of the load-displacement tests on pipes of different wall thickness, diameter and specimen heights were recorded. The experimental test results show that the PVC-U pipes are capable of supporting loads greater than the required design lo...

  14. Commercial high efficiency dehumidification systems using heat pipes

    Energy Technology Data Exchange (ETDEWEB)

    1993-09-01

    An improved heat pipe design using separately connected two-section one-way flow heat pipes with internal microgrooves instead of wicks is described. This design is now commercially available for use to increase the dehumidification capacity of air conditioning systems. The design also includes a method of introducing fresh air into buildings while recovering heat and controlling the humidity of the incoming air. Included are applications and case studies, load calculations and technical data, and installation, operation, and maintenance information.

  15. Heat pipe thermal control of slender optics probes

    International Nuclear Information System (INIS)

    Prenger, F.C.

    1979-01-01

    The thermal design for a stereographic viewing system is presented. The design incorporates an annular heat pipe and thermal isolation techniques. Test results are compared with design predictions for a prototype configuration. Test data obtained during heat pipe startup showing temperature gradients along the evaporator wall are presented. Correlations relating maximum wall temperature differences to a liquid Reynolds number were obtained at low power levels. These results are compared with Nusselt's Falling Film theory

  16. Heat pipes and use of heat pipes in furnace exhaust

    Science.gov (United States)

    Polcyn, Adam D.

    2010-12-28

    An array of a plurality of heat pipe are mounted in spaced relationship to one another with the hot end of the heat pipes in a heated environment, e.g. the exhaust flue of a furnace, and the cold end outside the furnace. Heat conversion equipment is connected to the cold end of the heat pipes.

  17. Flexible Cryogenic Heat Pipe Development Program

    Science.gov (United States)

    1976-01-01

    A heat pipe was designed for operation in the 100 - 200 K temperature range with maximum heat transport as a primary design goal; another designed for operation in the 15 - 100 K temperature range with maximum flexibility as a design goal. Optimum geometry and materials for the container and wicking systems were determined. The high power (100 - 200 K) heat pipe was tested with methane at 100 - 140 K, and test data indicated only partial priming with a performance limit of less than 50 percent of theoretical. A series of tests were conducted with ammonia at approximately 280 K to determine the performance under varying fluid charge and test conditions. The low temperature heat pipe was tested with oxygen at 85 - 95 K and with methanol at 295 - 315 K. Performance of the low temperature heat pipe was below theoretical predictions. Results of the completed testing are presented and possible performance limitation mechanisms are discussed. The lower-than-expected performance was felt to be due to small traces of non-condensible gases which prevented the composite wick from priming.

  18. Nuclear power plant piping prefabrication and assembly

    International Nuclear Information System (INIS)

    Schmidt, H.

    1990-01-01

    The piping design for nuclear power plants projects reveals, at the beginning, a modification through the application of new fabrication techniques for prefabrication and assembly. This report presents a fabrication methodology which aims to minimize the fabrication and assembly costs as well as to improve and assure quality. (Author) [es

  19. Dynamical focusing by bent, asymmetrically cut perfect crystals in Laue geometry.

    Science.gov (United States)

    Guigay, J P; Ferrero, C

    2016-07-01

    A semi-analytical approach based on the influence functions of a point source located on the crystal surface has been adopted to show that the focusing ability of cylindrically bent Laue crystals may be strongly enhanced by replacing symmetrically cut crystals with asymmetrically cut crystals. This approach is generally applicable to any distance between the X-ray source and the focusing bent crystal. A mathematically straightforward method to simplify the derivation of the already known expression of the influence functions in the case of deformed crystals with a constant strain gradient (e.g. cylindrically bent crystals) is also presented.

  20. Interpretation of bent-crystal rocking curves using phase-space diagrams

    CERN Document Server

    Ren, B; Chapman, L D; Wu, X Y; Zhong, Z; Ivanov, I; Huang, X

    2000-01-01

    In developing a double bent-Laue crystal monochromator for synchrotron-based monochromatic computed tomography system, we applied a special projection of the phase-space diagram to interpret the shape of bent crystal rocking curves. Unlike the rigorous approach of the ray-tracing method, this graphical method provides direct pictures that allow checks of the physical significance of the shapes of the rocking curves, thereby providing quick guidelines for matching two bent crystals. The method's usefulness is demonstrated with our crexperimental results, and its limitations are discussed.

  1. PE 100 pipe systems

    CERN Document Server

    Brömstrup, Heiner

    2012-01-01

    English translation of the 3rd edition ""Rohrsysteme aus PE 100"". Because of the considerably increased performance, pipe and pipe systems made from 100 enlarge the range of applications in the sectors of gas and water supply, sewage disposal, industrial pipeline construction and in the reconstruction and redevelopment of defective pipelines (relining). This book applies in particular to engineers, technicians and foremen working in the fields of supply, disposal and industry. Subject matters of the book are all practice-relevant questions regarding the construction, operation and maintenance

  2. Performance of buried pipe installation.

    Science.gov (United States)

    2010-05-01

    The purpose of this study is to determine the effects of geometric and mechanical parameters : characterizing the soil structure interaction developed in a buried pipe installation located under : roads/highways. The drainage pipes or culverts instal...

  3. Development of FBR piping bellows joint

    International Nuclear Information System (INIS)

    Tsukimori, Kazuyuki; Iwata, Koji

    1991-01-01

    Reduction of construction cost is one of the most important problems to realize a FBR (Fast Breeder Reactor) Plant. Significant reduction of the construction cost of a reactor building, related equipments and facilities can be expected by shortening the length of its long cooling pipes. Since the bellows has a great capacity for absorbing thermal expansion displacement, application of bellows expansion joints is considered as the most influential measure for reduction of the piping length. To confirm technological possibilities of application and practical use of bellows joints in the main piping systems, extensive R and D's, development of various methods for evaluating the strength of bellows, establishment of inspection and maintenance techniques, studies on safety logic, etc., were carried out by PNC from 1983 to 1988. Through these studies, technological possibilities of bellows joints were confirmed and the results were summarized in the 'Structural Design Guide for Class 1 Piping Bellows Expansion Joints of Fast Breeder Reactor for Elevated Temperature Service' and the 'Inspection and Maintenance Standards of Piping bellows expansion Joints'. (author)

  4. Identification of significant problems related to light water reactor piping systems

    International Nuclear Information System (INIS)

    1980-07-01

    Work on the project was divided into three tasks. In Task 1, past surveys of LWR piping system problems and recent Licensee Event Report summaries are studied to identify the significant problems of LWR piping systems and the primary causes of these problems. Pipe cracking is identified as the most recurring problem and is mainly due to the vibration of pipes due to operating pump-pipe resonance, fluid-flow fluctuations, and vibration of pipe supports. Research relevant to the identified piping system problems is evaluated. Task 2 studies identify typical LWR piping systems and the current loads and load combinations used in the design of these systems. Definitions of loads are reviewed. In Task 3, a comparative study is carried out on the use of nonlinear analysis methods in the design of LWR piping systems. The study concludes that the current linear-elastic methods of analysis may not predict accurately the behavior of piping systems under seismic loads and may, under certain circumstances, result in nonconservative designs. Gaps at piping supports are found to have a significant effect on the response of the piping systems

  5. Impact test on a pipe

    International Nuclear Information System (INIS)

    Noronha, R.F.; Shimura, S.H.

    1995-01-01

    A carbon steel pipe was submitted to a series of progressive impact loadings on a drop table. Strain and acceleration were measured in relevant places of the pipe and recorded in time and frequency domain. The pipe withstood impact loads up to 560 G without any visual deformation being noticed. Strains 50% over the yield point strain were measured. A high level of damping coming from the supports may have attenuated the response of the pipe. (author). 4 refs., 1 fig., 1 tab

  6. Welded joints engineering design of the primary circuit, surge line and main steam piping of the Angra 2 reactor; Projeto de engenharia das juntas soldadas do circuito primario, linha de surto e linha de vapor principal de Angra 2

    Energy Technology Data Exchange (ETDEWEB)

    Volta, Angelo Roberto; Couto, Jose Gonzalo Villaverde [NUCLEN, Rio de Janeiro, RJ (Brazil)

    1995-12-31

    The erection of nuclear systems of a Nuclear Power Station is under international requests, that results in a detailed elaboration of documents for the performance of welds. NUCLEN as an engineering design company, responsible for the erection of Angra 2, developed a suitable software program for the elaboration of welding procedure qualifications, tests and examination sequence plans and heat treatment plans applied to primary circuit, surgeline and main steam piping. The paper shows the employed methodology for the elaboration of these documents, as well as the requested engineering design of welding technology and testability in order to assure the stipulated quality level, according to requirements of the specifications, codes and norms. (author). 6 refs.

  7. The development of a practical pipe auto-routing system in a shipbuilding CAD environment using network optimization

    Science.gov (United States)

    Kim, Shin-Hyung; Ruy, Won-Sun; Jang, Beom Seon

    2013-09-01

    An automatic pipe routing system is proposed and implemented. Generally, the pipe routing design as a part of the shipbuilding process requires a considerable number of man hours due to the complexity which comes from physical and operational constraints and the crucial influence on outfitting construction productivity. Therefore, the automation of pipe routing design operations and processes has always been one of the most important goals for improvements in shipbuilding design. The proposed system is applied to a pipe routing design in the engine room space of a commercial ship. The effectiveness of this system is verified as a reasonable form of support for pipe routing design jobs. The automatic routing result of this system can serve as a good basis model in the initial stages of pipe routing design, allowing the designer to reduce their design lead time significantly. As a result, the design productivity overall can be improved with this automatic pipe routing system

  8. The development of a practical pipe auto-routing system in a shipbuilding CAD environment using network optimization

    Directory of Open Access Journals (Sweden)

    Shin-Hyung Kim

    2013-09-01

    Full Text Available An automatic pipe routing system is proposed and implemented. Generally, the pipe routing design as a part of the shipbuilding process requires a considerable number of man hours due to the complexity which comes from physical and operational constraints and the crucial influence on outfitting construction productivity. Therefore, the automation of pipe routing design operations and processes has always been one of the most important goals for improvements in shipbuilding design. The proposed system is applied to a pipe routing design in the engine room space of a commercial ship. The effectiveness of this system is verified as a reasonable form of support for pipe routing design jobs. The automatic routing result of this system can serve as a good basis model in the initial stages of pipe routing design, allowing the designer to reduce their design lead time significantly. As a result, the design productivity overall can be improved with this automatic pipe routing system.

  9. Development of pipe layout system

    International Nuclear Information System (INIS)

    Ota, Yoshimi; Yamamoto, Shigeru; Tokumasu, Shinji; Yamaguchi, Yukio; Besho, Hiromi; Sakano, Tatuo.

    1986-01-01

    In the plant design carried out so far, the process up to final drawings has been the repetition of the correction of drawings. This is because the space as the object of design is finite, and it is difficult to lay many pipes efficiently. Especially in nuclear power plants, the quantity of materials required for ensuring the safety and quality control is enormous, and only the skilled engineers having rich experience have become unable to deal with it. The model engineering using plastic models has been adopted, but still there are problems. In order to solve this problem, the development of the system for unitarily managing the various design information of plants with a computer, checking up various design with this information, automatically outputting design drawings and management data, and heightening the quality of design, synchronizing the progress, increasing the speed and saving the labor of design was carried out. This system is versatile and can be used for all plants. The emphasis in the development was placed on compact data structure, rapid picture processing and easy operation. The present status of design and the automation, the basic design of the system, the function of the system, the internal expression of models, the method of picture processing, and the results of application are reported. (Kako, I.)

  10. Optimization of Pipe Networks

    DEFF Research Database (Denmark)

    Hansen, C. T.; Madsen, Kaj; Nielsen, Hans Bruun

    1991-01-01

    algorithm using successive linear programming is presented. The performance of the algorithm is illustrated by optimizing a network with 201 pipes and 172 nodes. It is concluded that the new algorithm seems to be very efficient and stable, and that it always finds a solution with a cost near the best...

  11. HPFRCC - Extruded Pipes

    DEFF Research Database (Denmark)

    Stang, Henrik; Pedersen, Carsten

    1996-01-01

    The present paper gives an overview of the research onHigh Performance Fiber Reinforced Cementitious Composite -- HPFRCC --pipes recently carried out at Department of Structural Engineering, Technical University of Denmark. The project combines material development, processing technique developme...... of the newly extruded material....

  12. EXPERIMENTAL AND NUMERICAL INVESTIGATION OF FLEXIBLE BURIED PIPE DEFORMATION BEHAVIOR UNDER VARIOUS BACKFILL CONDITIONS

    Directory of Open Access Journals (Sweden)

    Niyazi Uğur TERZİ

    2009-01-01

    Full Text Available Deformation characteristics of polyethylene based flexible pipes are different than rigid pipes such as concrete and iron pipes. Deflection patterns and stress-strain behaviors of flexible pipes have strict relation between the engineering properties of backfill and its settlement method. In this study, deformation behavior of a 100 mm HDPE flexible pipe under vertical loads is investigated in laboratory conditions. Steel test box, pressurized membrane, raining system, linear position transducers and strain gauge rosettes are used in the laboratory tests. In order to analyze the buried pipe performance; Masada Derivation Formula which is mostly used by designers is employed. According to the test and mathematical studies, it is understood that relative density of backfill and its settlement method is a considerable effect on buried pipe performance and Masada Derivation method is very efficient for predicting the pipe performance.

  13. PPOOLEX experiments with a modified blowdown pipe outlet

    International Nuclear Information System (INIS)

    Laine, J.; Puustinen, M.; Raesaenen, A.

    2009-08-01

    This report summarizes the results of the experiments with a modified blowdown pipe outlet carried out with the PPOOLEX test facility designed and constructed at Lappeenranta University of Technology. Steam was blown into the dry well compartment and from there through a vertical DN200 blowdown pipe to the condensation pool. Four reference experiments with a straight pipe and ten with the Forsmark type collar were carried out. The main purpose of the experiment series was to study the effect of a blowdown pipe outlet collar design on loads caused by chugging phenomena (rapid condensation) while steam is discharged into the condensation pool. The PPOOLEX test facility is a closed stainless steel vessel divided into two compartments, dry well and wet well. During the experiments the initial temperature level of the condensation pool water was either 20-25 or 50-55 deg. C. The steam flow rate varied from 400 to 1200 g/s and the temperature of incoming steam from 142 to 185 deg. C. In the experiments with 20-25 deg. C pool water, even 10 times higher pressure pulses were measured inside the blowdown pipe in the case of the straight pipe than with the collar. In this respect, the collar design worked as planned and removed the high pressure spikes from the blowdown pipe. Meanwhile, there seemed to be no suppressing effect on the loads due to the collar in the pool side in this temperature range. Registered loads in the pool were approximately in the same range (or even a little higher) with the collar as with the straight pipe. In the experiments with 50-55 deg. C pool water no high pressure pulses were measured inside the blowdown pipe either with the straight pipe or with the collar. In this case, more of the suppressing effect is probably due to the warmer pool water than due to the modified pipe outlet. It has been observed already in the earlier experiments with a straight pipe in the POOLEX and PPOOLEX facilities that warm pool water has a diminishing effect on

  14. Evaluation of bent caps in reinforced concrete deck girder bridges : part 2.

    Science.gov (United States)

    2008-09-01

    This report describes research conducted to enable evaluation of existing vintage bent cap beams in reinforced concrete : deck girder bridges. The report is organized into two parts: 1) flexural anchorage capacity response and prediction of : reduced...

  15. Evaluation of bent caps in reinforced concrete deck girder bridges : part 1.

    Science.gov (United States)

    2008-09-01

    This report describes research conducted to enable evaluation of existing vintage bent cap beams in reinforced concrete : deck girder bridges. The report is organized into two parts: 1) flexural anchorage capacity response and prediction of : reduced...

  16. Behavior of Pile to Bent Cap Connections Subjected to Seismic Forces

    Science.gov (United States)

    2012-06-01

    Currently the South Carolina Department of Transportation employs a detail of a plain pile embedment for the : connection between precast prestressed piles and cast-in-place bent caps. This connection has proved beneficial in terms : of time and cost...

  17. Seismic performance of an I-girder to inverted-T bent cap connection.

    Science.gov (United States)

    2011-09-01

    This report presents the research conducted as part of an investigation for the California Department of Transportation (Caltrans) regarding the seismic response and overall moment capacity of precast I-girder to inverted-T bent cap bridge connection...

  18. A numerical analysis on thermal stratification phenomenon in the SCS piping

    International Nuclear Information System (INIS)

    Kim, Kwang Chu; Park, Man Heung; Youm, Hag Ki; Lee, Sun Ki; Kim, Tae Ryong

    2003-01-01

    A numerical study is performed to estimate on an unsteady thermal stratification phenomenon in the Shutdown Cooling System(SCS) piping branched off the Reactor Coolant System(RCS) piping of Nuclear Power Plant. In the results, turbulent penetration reaches to the 1 st isolation valve. At 500sec, the maximum temperature difference between top and bottom inner wall in piping is observed at the starting point of horizontal piping passing elbow. The temperature of coolant in the rear side of the 1 st isolation valve disk is very slowly increased and the inflection point in temperature difference curve for time is observed at 2700sec. At the beginning of turbulent penetration from RCS piping, the fast inflow generates the higher temperature for the inner wall than the outer wall in the SCS piping. In the case the hot-leg injection piping and the drain piping are connected to the SCS piping, the effect of thermal stratification in the SCS piping is decreased due to an increase of heat loss compared with no connection case. The hot-leg injection piping affected by turbulent penetration from the SCS piping has a severe temperature difference that exceeds criterion temperature stated in reference. But the drain piping located in the rear compared with the hot-leg injection piping shows a tiny temperature difference. In a viewpoint of designer, for the purpose of decreasing the thermal stratification effect, it is necessary to increase the length of vertical piping in the SCS piping, and to move the position of the hot-leg injection piping backward

  19. Solid0Core Heat-Pipe Nuclear Batterly Type Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Ehud Greenspan

    2008-09-30

    This project was devoted to a preliminary assessment of the feasibility of designing an Encapsulated Nuclear Heat Source (ENHS) reactor to have a solid core from which heat is removed by liquid-metal heat pipes (HP).

  20. Additive Manufacturing of Heat Pipe Wicks, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Wick properties are often the limiting factor in a heat pipe design. Current technology uses conventional sintering of metal powders, screen wick, or grooves to...

  1. Compressed air piping, 241-SY-101 hydraulic pump retrieval trailer

    International Nuclear Information System (INIS)

    Wilson, T.R.

    1994-01-01

    The following Design Analysis was prepared by the Westinghouse Hanford Company to determine pressure losses in the compressed air piping installed on the hydraulic trailer for the 241-SY-101 pump retrieval mission

  2. Laser application of heat pipe technology in energy related programs

    International Nuclear Information System (INIS)

    Carbone, R.J.

    1975-01-01

    The design and operating parameters for a heat pipe laser utilizing metal vapors are proposed. The laser would be applied to laser induced fusion, laser induced chemistry, laser isotope separation, and power transport using optical beams. (U.S.)

  3. Condensation driven water hammer studies for feedwater distribution pipe

    Energy Technology Data Exchange (ETDEWEB)

    Savolainen, S.; Katajala, S.; Elsing, B.; Nurkkala, P.; Hoikkanen, J. [Imatran Voima Oy, Vantaa (Finland); Pullinen, J. [IVO Power Engineering Ltd., Vantaa (Finland); Logvinov, S.A.; Trunov, N.B.; Sitnik, J.K. [EDO Gidropress (Russian Federation)

    1997-12-31

    Imatran Voima Oy, IVO, operates two VVER 440 reactors. Unit 1 has been operating since 1977 and unit 2 since 1981. First damages of the feed water distribution (FWD) pipes were observed in 1989. In closer examinations FWD-pipe T-connection turned out to suffer from severe erosion corrosion damages. Similar damages have been found also in other VVER 440 type NPPs. In 1994 the first new FWD-pipe was replaced and in 1996 extensive water hammer experiments were carried out together with EDO Gidropress in Podolsk. After the first phase of the experiments some fundamental changes were made to the construction of the FWD-pipe. The object of this paper is to give short insight to the design of the new FWD-pipe concentrating on water hammer experiments. (orig.).

  4. Condensation driven water hammer studies for feedwater distribution pipe

    International Nuclear Information System (INIS)

    Savolainen, S.; Katajala, S.; Elsing, B.; Nurkkala, P.; Hoikkanen, J.; Pullinen, J.; Logvinov, S.A.; Trunov, N.B.; Sitnik, J.K.

    1997-01-01

    Imatran Voima Oy, IVO, operates two VVER 440 reactors. Unit 1 has been operating since 1977 and unit 2 since 1981. First damages of the feed water distribution (FWD) pipes were observed in 1989. In closer examinations FWD-pipe T-connection turned out to suffer from severe erosion corrosion damages. Similar damages have been found also in other VVER 440 type NPPs. In 1994 the first new FWD-pipe was replaced and in 1996 extensive water hammer experiments were carried out together with EDO Gidropress in Podolsk. After the first phase of the experiments some fundamental changes were made to the construction of the FWD-pipe. The object of this paper is to give short insight to the design of the new FWD-pipe concentrating on water hammer experiments. (orig.)

  5. Microfocusing of soft X-ray undulator light using an elliptically bent cylinder mirror

    CERN Document Server

    Miura, S; Mashima, K; Miyaji, A; Ishiguro, E; Ohashi, H; Tamenori, Y; Okumura, H; Kanashima, T; Ishikawa, T

    2001-01-01

    The performance of an elliptically bent cylinder mirror, installed in A-branch of the Soft X-ray photochemistry beamline (BL27SU) at the SPring-8, is described. The aim of this branch beamline is to provide a micro white-beam focusing for a need in photochemistry community. This elastically bent mirror is the key component for the extremely intense micro-beam focusing optics.

  6. Photoelastic investigation of the stresses in mitred bent-cylinders under bending, 2

    International Nuclear Information System (INIS)

    Sawa, Yoshiaki

    1984-01-01

    The states of stress distribution in mitred bend subjected to inplane uniform bending moment have been studied systematically by means of photoelastic stress freezing method. The relations between the stress concentration factor of fiber stress σsub(l) and of hoop stress σsub(theta) near the bent part and the angle of mitred bend are thoroughly investigated. The effects of fillet radius of the bent-part and wall thickness on the stress concentration factors are also discussed. (author)

  7. Dechanneling of relativistic protons and nuclei in straight and bent crystals. Rechanneling role

    International Nuclear Information System (INIS)

    Taratin, A.M.

    1997-01-01

    Planar dechanneling of relativistic protons and Pb nuclei with the same momentum per unit charge p z in straight and bent crystals was investigated by simulation. It was shown that the different probability of the recapture into the channeling regime for protons and Pb nuclei infringes the dechanneling length invariance with respect to p z in the straight crystals, whereas in the bent crystals the approximate invariance occurs

  8. On Weak and Strong 2k- bent Boolean Functions

    Science.gov (United States)

    2016-01-01

    s8 (u) + β2Wf⊕ s8 (ū) + β3Wf⊕s2⊕ s8 (u) + β4Wf⊕s2⊕ s8 (ū) + β5Wf⊕s4⊕ s8 (u) + β6Wf⊕s4⊕ s8 (ū...β7Wf⊕s2⊕s4⊕ s8 (u) + β8Wf⊕s2⊕s4⊕ s8 (ū), where β1 = 1 + ζ + ζ2 + ζ3 + ζ4 + ζ5 + ζ6 + ζ7, β2 = 1− ζ + ζ2 − ζ3 + ζ4 − ζ5 + ζ6 − ζ7, β3 = 1 + ζ − ζ2 − ζ3...n odd hold, where: (i) f⊕ s8 is bent-negabent-octabent with the conditions that (Wf⊕ s8 (u), Wf⊕ s8 (ū), Wf⊕s2⊕ s8 (u), Wf⊕s2⊕ s8 (ū), Wf⊕s4⊕ s8 (u), Wf⊕s4⊕ s8

  9. Nematic biaxiality in a bent-core material

    Science.gov (United States)

    Yoon, Hyung Guen; Kang, Shin-Woong; Dong, Ronald Y.; Marini, Alberto; Suresh, Kattera A.; Srinivasarao, Mohan; Kumar, Satyendra

    2010-05-01

    The results of a recent investigation of the nematic biaxiality in a bent-core mesogen (A131) are in apparent disagreement with earlier claims. Samples of mesogen A131 used in the two studies were investigated with polarized optical microscopy, conoscopy, carbon-13 NMR, and crossover frequency measurements. The results demonstrate that textural changes associated with the growth of biaxial nematic order appear at ˜149°C . The Maltese cross observed in the conoscopic figure gradually splits into two isogyres at lower temperatures indicating phase biaxiality. Presence of the uniaxial to biaxial nematic phase transition is further confirmed by temperature trends of local order parameters based on C13 chemical shifts in NMR experiments. Frequency switching measurements also clearly reveal a transition at 149°C . Differences between the two reports appear to be related to the presence of solvent, impurities, and/or adsorbed gases in samples of A131 used in the study of Van Le [Phys. Rev. E 79, 030701 (2009)].

  10. Experimental investigation on Heat Transfer Performance of Annular Flow Path Heat Pipe

    International Nuclear Information System (INIS)

    Kim, In Guk; Kim, Kyung Mo; Jeong, Yeong Shin; Bang, In Cheol

    2015-01-01

    Mochizuki et al. was suggested the passive cooling system to spent nuclear fuel pool. Detail analysis of various heat pipe design cases was studied to determine the heat pipes cooling performance. Wang et al. suggested the concept PRHRS of MSR using sodium heat pipes, and the transient performance of high temperature sodium heat pipe was numerically simulated in the case of MSR accident. The meltdown at the Fukushima Daiichi nuclear power plants alarmed to the dangers of station blackout (SBO) accident. After the SBO accident, passive decay heat removal systems have been investigated to prevent the severe accidents. Mochizuki et al. suggested the heat pipes cooling system using loop heat pipes for decay heat removal cooling and analysis of heat pipe thermal resistance for boiling water reactor (BWR). The decay heat removal systems for pressurized water reactor (PWR) were suggested using natural convection mechanisms and modification of PWR design. Our group suggested the concept of a hybrid heat pipe with control rod as Passive IN-core Cooling System (PINCs) for decay heat removal for advanced nuclear power plant. Hybrid heat pipe is the combination of the heat pipe and control rod. In the present research, the main objective is to investigate the effect of the inner structure to the heat transfer performance of heat pipe containing neutron absorber material, B 4 C. The main objective is to investigate the effect of the inner structure in heat pipe to the heat transfer performance with annular flow path. ABS pellet was used instead of B 4 C pellet as cylindrical structures. The thermal performances of each heat pipes were measured experimentally. Among them, concentric heat pipe showed the best performance compared with others. 1. Annular evaporation section heat pipe and annular flow path heat pipe showed heat transfer degradation. 2. AHP also had annular vapor space and contact cooling surface per unit volume of vapor was increased. Heat transfer coefficient of

  11. Evaluation of seismic margins for an in-plant piping system

    International Nuclear Information System (INIS)

    Kot, C.A.; Srinivasan, M.G.; Hsieh, B.J.

    1991-01-01

    Earthquake experience as well as experiments indicate that, in general, piping systems are quite rugged in resisting seismic loadings. Therefore there is a basis to hold that the seismic margin against pipe failure is very high for systems designed according to current practice. However, there is very little data, either from tests or from earthquake experience, on the actual margin or excess capacity (against failure from seismic loading) of in-plant piping systems. Design of nuclear power plant piping systems in the US is governed by the criteria given in the ASME Boiler and Pressure Vessel (B ampersand PV) Code, which assure that pipe stresses are within specified allowable limits. Generally linear elastic analytical methods are used to determine the stresses in the pipe and forces in pipe supports. The objective of this study is to verify that piping designed according to current practice does indeed have a large margin against failure and to quantify the excess capacity for piping and dynamic pipe supports on the basis of data obtained in a series of high-level seismic experiments (designated SHAM) on an in-plant piping system at the HDR (Heissdampfreaktor) Test Facility in Germany. Note that in the present context, seismic margin refers to the deterministic excess capacities of piping or supports compared to their design capacities. The excess seismic capacities or margins of a prototypical in-plant piping system and its components are evaluated by comparing measured inputs and responses from high-level simulated seismic experiments with design loads and allowables. Large excess capacities are clearly demonstrated against pipe and overall system failure with the lower bound being about four. For snubbers the lower bound margin is estimated at two and for rigid strut supports at five. 4 refs., 2 figs., 2 tabs

  12. Heat pipe applications workshop report

    International Nuclear Information System (INIS)

    Ranken, W.A.

    1978-04-01

    The proceedings of the Heat Pipe Applications Workshop, held at the Los Alamos Scientific Laboratory October 20-21, 1977, are reported. This workshop, which brought together representatives of the Department of Energy and of a dozen industrial organizations actively engaged in the development and marketing of heat pipe equipment, was convened for the purpose of defining ways of accelerating the development and application of heat pipe technology. Recommendations from the three study groups formed by the participants are presented. These deal with such subjects as: (1) the problem encountered in obtaining support for the development of broadly applicable technologies, (2) the need for applications studies, (3) the establishment of a heat pipe technology center of excellence, (4) the role the Department of Energy might take with regard to heat pipe development and application, and (5) coordination of heat pipe industry efforts to raise the general level of understanding and acceptance of heat pipe solutions to heat control and transfer problems

  13. Vibration testing and analysis of a multiply supported piping system

    International Nuclear Information System (INIS)

    Hsieh, B.J.; Kot, C.A.; Srinivasan, M.G.

    1987-01-01

    The behavior of nuclear power plant piping systems during earthquake, and the most appropriate and economical mode of supporting such piping, is an issue of major concern. Consequently, the verification and validation of piping analysis methods and assumptions used in the design and safety assessment of nuclear power plants are of great interest. As part of its program on the validation of seismic calculational methods the US Nuclear Regulatory Commission (NRC) is specifically interested in the validation of the multiple support piping analysis module of the SMACS (Seismic Methodology Analysis Chain with Statistics) computer code. Data for the comparison of the dynamic behavior of various pipe hanger configurations and for the validation of piping response analyses were recently obtained in the large shaker experiments (SHAG) conducted at the HDR (Heissdampfreaktor) test facility in Kahl/Main, Federal Republic of Germany. This paper describes preliminary results from the SHAG piping response tests and the approach taken in the validation of the SMACS code piping analysis

  14. OPDE-The international pipe failure data exchange project

    International Nuclear Information System (INIS)

    Lydell, Bengt; Riznic, Jovica

    2008-01-01

    Certain member countries of the Organization for Economic Cooperation and development (OECD) in 2002 established the OECD pipe failure data exchange project (OPDE) to produce an international database on the piping service experience applicable to commercial nuclear power plants. OPDE is operated under the umbrella of the OECD Nuclear Energy Agency (NEA). The Project collects pipe failure data including service-induced wall thinning, part through-wall crack, pinhole leak, leak, and rupture/severance (i.e., events involving large through-wall flow rates up to and beyond the make-up capacity of engineered safeguards systems). The part through-wall events include degradation in excess of design code allowable for pipe wall thinning or crack depth. OPDE also addresses such degradation that could have generic implications regarding the reliability of in-service inspection. Currently the OPDE database includes approximately 3,700 records on pipe failure affecting ASME Code Class 1 through 3 and non-safety-related (non-Code) piping. This paper presents the motivations and objectives behind the establishment of the OPDE project. The paper also summarizes the unique data quality considerations that are associated with the reporting and recording of piping component degradation and failure. An overview of the database content is included to place it in perspective relative to past efforts to systematically collect and evaluate service experience data on piping performance. Finally, a brief summary is given of current database application studies

  15. Performance predictions and measurements for space-power-system heat pipes

    International Nuclear Information System (INIS)

    Prenger, F.C. Jr.

    1981-01-01

    High temperature liquid metal heat pipes designed for space power systems have been analyzed and tested. Three wick designs are discussed and a design rationale for the heat pipe is provided. Test results on a molybdenum, annular wick heat pipe are presented. Performance limitations due to boiling and capillary limits are presented. There is evidence that the vapor flow in the adiabatic section is turbulent and that the transition Reynolds number is 4000

  16. Experimental investigation of zero phase shift effects for Coriolis flowmeters due to pipe imperfections

    DEFF Research Database (Denmark)

    Enz, Stephanie; Thomsen, Jon Juel; Neumeyer, Stefan

    2011-01-01

    damping and mass, and on ambient temperature changes. Experimental observations confirm the hypothesis that asymmetry in the axial distribution of damping will induce zero shifts similar to the phase shifts due to fluid flow. Axially symmetrically distributed damping was observed to influence phase shift......, the flexural vibrations of two bent, parallel, non-fluid-conveying pipes are studied experimentally, employing an industrial CFM. Special attention has been paid on the phase shift in the case of zero mass flow, i.e. the zero shift, caused by various imperfections to the ‘‘perfect’’ CFM, i.e. non-uniform pipe...... at an order of magnitude smaller than the primary effect of mass flow, while small added mass and ambient temperature changes induced zero shifts two orders of magnitude smaller than the phase shifts due to mass flow. The order of magnitude of the induced zero shifts indicates that non-uniform damping, added...

  17. Fundamental distribution of stress corrosion crack depth on Type 316L stainless steels induced by creviced bent beam test

    International Nuclear Information System (INIS)

    Miyahara, Yuichi; Miura, Yasufumi; Kako, Kenji

    2014-01-01

    The creviced bent beam (CBB) test has been applied for many materials such as nickel base alloys and low carbon austenitic stainless steels. For sensitized austenitic stainless steels, fundamental distribution of crack depth induced by CBB tests was evaluated to establish SCC initiation model and lifetime prediction method. On the other hand, there are a few studies about distribution of crack depth on low carbon austenitic stainless steels. In this study, statistical analysis of crack depth was conducted in Type 316L stainless steels after CBB tests. The results are summarized as follows, (1) Distribution of grain boundary depth designated as distance from surface to triple point of grain boundary fit lognormal probability distribution and exponential probability distribution. (2) Distribution of crack depth approaches lognormal or exponential probability distribution with passage of test duration. Distribution of plastic strain on the specimen surface is not affect to type of crack depth distribution. (3) Inflection or bent point appears on the probability plot at depth of the median of grain boundary depth distribution. (4) Less than median of grain boundary depth, distribution of crack depth is identical to grain boundary depth distribution. More than median + standard deviation of grain boundary depth, crack depth distribution is described by the exponential distribution. (author)

  18. Drill pipe protector development

    Energy Technology Data Exchange (ETDEWEB)

    Thomerson, C.; Kenne, R. [Regal International Corp., Corsicanna, TX (United States); Wemple, R.P. [Sandia National Lab., Albuquerque, NM (United States)] [ed.] [and others

    1996-03-01

    The Geothermal Drilling Organization (GDO), formed in the early 1980s by the geothermal industry and the U.S. Department of Energy (DOE) Geothermal Division, sponsors specific development projects to advance the technologies used in geothermal exploration, drilling, and production phases. Individual GDO member companies can choose to participate in specific projects that are most beneficial to their industry segment. Sandia National Laboratories is the technical interface and contracting office for the DOE in these projects. Typical projects sponsored in the past have included a high temperature borehole televiewer, drill bits, muds/polymers, rotary head seals, and this project for drill pipe protectors. This report documents the development work of Regal International for high temperature geothermal pipe protectors.

  19. Diffusion in flexible pipes

    Energy Technology Data Exchange (ETDEWEB)

    Brogaard Kristensen, S.

    2000-06-01

    This report describes the work done on modelling and simulation of the complex diffusion of gas through the wall of a flexible pipe. The diffusion and thus the pressure in annulus depends strongly on the diffusion and solubility parameters of the gas-polymer system and on the degree of blocking of the outer surface of the inner liner due to pressure reinforcements. The report evaluates the basis modelling required to describe the complex geometries and flow patterns. Qualitatively results of temperature and concentration profiles are shown in the report. For the program to serve any modelling purpose in 'real life' the results need to be validated and possibly the model needs corrections. Hopefully, a full-scale test of a flexible pipe will provide the required temperatures and pressures in annulus to validate the models. (EHS)

  20. Qualification of PHT piping of Indian 500 MW PHWR for LBB, using R-6 method

    International Nuclear Information System (INIS)

    Rastogi, Rohit; Bhasin, V.; Kushwaha, H.S.

    1997-01-01

    This document discusses the qualification of straight pipe portion of the primary heat transport (PHT) piping of Indian 500 MWe pressurised heavy water reactor (PHWR) for leak before break (LBB). The evaluation is done using R-6 [1] method. The results presented here are: the safety margins which exist on straight pipe components of main PHT piping of 500 MWe, under leakage size crack (LSC) and design basis accident loads; the sensitivity of safety margins with respect to different analysis parameters and the qualification of PHT piping for LBB based on criterion given by NUREG-1061 [2] and TECDOC-774 [3]. (author)

  1. The stress analysis evaluation and pipe support layout for pressurizer discharge system

    International Nuclear Information System (INIS)

    Mao Qing; Wang Wei; Zhang Yixiong

    2000-01-01

    The author presents the stress analysis and evaluation of pipe layout and support adjustment process for Qinshan phase II pressurizer discharge system. Using PDL-SYSPIPE INTERFACE software, the characteristic parameters of the system are gained from 3-D CAD engineering design software PDL and outputted as the input date file format of special pipe stress analysis program SYSPIPE. Based on that, SYSPIPE program fast stress analysis function is applied in adjusting pipe layout , support layout and support types. According to RCC-M standard, the pipe stress analysis and evaluation under deadweight, internal pressure, thermal expansion, seismic, pipe rupture and discharge loads are fulfilled

  2. LHCb: Beam Pipe portrait

    CERN Multimedia

    LHCb, Collaboration

    2005-01-01

    The proton beams circulate in the accelerator in Ultra High Vacuum to make them interact only with each other when colliding at the interaction point. A special beam pipe "holds" the vacuum where they pass through the LHCb detector: it has to be mechanically very strong to stand the difference in pressure between the vacuum inside it and the air in the cavern but also be as transparent as possible for the particles originating in the proton−proton collisions.

  3. LHCb: Beam Pipe

    CERN Multimedia

    LHCb, Collaboration

    2005-01-01

    The proton beams circulate in the accelerator in Ultra High Vacuum to make them interact only with each other when colliding at the interaction point. A special beam pipe "holds" the vacuum where they pass through the LHCb detector:it has to be mechanically very strong to stand the difference in pressure between the vacuum inside it and the air in the cavern but also be as transparent as possible for the particles originating in the proton−proton collisions.

  4. Investigation on size tolerance of pore defect of girth weld pipe

    Science.gov (United States)

    Shuai, Jian; Xu, Kui

    2018-01-01

    Welding quality control is an important parameter for safe operation of oil and gas pipes, especially for high-strength steel pipes. Size control of welding defect is a bottleneck problem for current pipe construction. As a key part of construction procedure for butt-welding of pipes, pore defects in girth weld is difficult to ignore. A three-dimensional non-linear finite element numerical model is established to study applicability of size control indices based on groove shape and softening phenomenon of material in heat-affected zone of practical pipe girth weld. Taking design criteria of pipe as the basis, basic tensile, extremely tensile and extremely compressive loading conditions are determined for pipe stress analysis, and failure criteria based on flow stress is employed to perform stress analysis for pipe girth weld with pore defect. Results show that pipe girth welding stresses of pores at various radial locations are similar. Whereas, stress for pores of different sharpness varied significantly. Besides, tolerance capability of API 5L X90 grade pipe to pore defect of girth weld is lower than that of API 5L X80 grade pipe, and size control index of 3 mm related to pore defect in current standards is applicable to API 5L X80 and X90 grade girth welded pipes with radially non-sharp pore defects. PMID:29364986

  5. Pipe inspection using the pipe crawler. Innovative technology summary report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-05-01

    The US Department of Energy (DOE) continually seeks safer and more cost-effective remediation technologies for use in the decontamination and decommissioning (D and D) of nuclear facilities. In several of the buildings at the Fernald Site, there is piping that was used to transport process materials. As the demolition of these buildings occur, disposal of this piping has become a costly issue. Currently, all process piping is cut into ten-foot or less sections, the ends of the piping are wrapped and taped to prevent the release of any potential contaminants into the air, and the piping is placed in roll off boxes for eventual repackaging and shipment to the Nevada Test Site (NTS) for disposal. Alternatives that allow for the onsite disposal of process piping are greatly desired due to the potential for dramatic savings in current offsite disposal costs. No means is currently employed to allow for the adequate inspection of the interior of piping, and consequently, process piping has been assumed to be internally contaminated and thus routinely disposed of at NTS. The BTX-II system incorporates a high-resolution micro color camera with lightheads, cabling, a monitor, and a video recorder. The complete probe is capable of inspecting pipes with an internal diameter (ID) as small as 1.4 inches. By using readily interchangeable lightheads, the same system is capable of inspecting piping up to 24 inches in ID. The original development of the BTX system was for inspection of boiler tubes and small diameter pipes for build-up, pitting, and corrosion. However, the system is well suited for inspecting the interior of most types of piping and other small, confined areas. The report describes the technology, its performance, uses, cost, regulatory and policy issues, and lessons learned.

  6. Pipe inspection using the pipe crawler. Innovative technology summary report

    International Nuclear Information System (INIS)

    1999-05-01

    The US Department of Energy (DOE) continually seeks safer and more cost-effective remediation technologies for use in the decontamination and decommissioning (D and D) of nuclear facilities. In several of the buildings at the Fernald Site, there is piping that was used to transport process materials. As the demolition of these buildings occur, disposal of this piping has become a costly issue. Currently, all process piping is cut into ten-foot or less sections, the ends of the piping are wrapped and taped to prevent the release of any potential contaminants into the air, and the piping is placed in roll off boxes for eventual repackaging and shipment to the Nevada Test Site (NTS) for disposal. Alternatives that allow for the onsite disposal of process piping are greatly desired due to the potential for dramatic savings in current offsite disposal costs. No means is currently employed to allow for the adequate inspection of the interior of piping, and consequently, process piping has been assumed to be internally contaminated and thus routinely disposed of at NTS. The BTX-II system incorporates a high-resolution micro color camera with lightheads, cabling, a monitor, and a video recorder. The complete probe is capable of inspecting pipes with an internal diameter (ID) as small as 1.4 inches. By using readily interchangeable lightheads, the same system is capable of inspecting piping up to 24 inches in ID. The original development of the BTX system was for inspection of boiler tubes and small diameter pipes for build-up, pitting, and corrosion. However, the system is well suited for inspecting the interior of most types of piping and other small, confined areas. The report describes the technology, its performance, uses, cost, regulatory and policy issues, and lessons learned

  7. Standard practice for preparation and use of Bent-Beam stress-corrosion test specimens

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2011-01-01

    1.1 This practice covers procedures for designing, preparing, and using bent-beam stress-corrosion specimens. 1.2 Different specimen configurations are given for use with different product forms, such as sheet or plate. This practice applicable to specimens of any metal that are stressed to levels less than the elastic limit of the material, and therefore, the applied stress can be accurately calculated or measured (see Note 1). Stress calculations by this practice are not applicable to plastically stressed specimens. Note 1—It is the nature of these practices that only the applied stress can be calculated. Since stress-corrosion cracking is a function of the total stress, for critical applications and proper interpretation of results, the residual stress (before applying external stress) or the total elastic stress (after applying external stress) should be determined by appropriate nondestructive methods, such as X-ray diffraction (1). 1.3 Test procedures are given for stress-corrosion testing by ex...

  8. Performances of a bent-crystal spectrometer adapted to resonant x-ray emission measurements on gas-phase samples

    Energy Technology Data Exchange (ETDEWEB)

    Journel, Loiec; El Khoury, Lara; Marin, Thierry; Guillemin, Renaud; Carniato, Stephane; Avila, Antoine; Delaunay, Renaud; Hague, Coryn F.; Simon, Marc [Laboratoire de Chimie Physique-Matiere et Rayonnement, UPMC University of Paris 06, UMR 7614, F-75005 Paris (France) and Laboratoire de Chimie Physique-Matiere et Rayonnement, CNRS, UMR 7614, F-75005 Paris (France)

    2009-09-15

    We describe a bent-crystal spectrometer adapted to measure x-ray emission resulting from core-level excitation of gas-phase molecules in the 0.8-8 keV energy range. The spectrometer is based on the Johann principle, and uses a microfocused photon beam to provide high-resolution (resolving power of {approx}7500). A gas cell was designed to hold a high-pressure (300 mbar) sample of gas while maintaining a high vacuum (10{sup -9} mbar) in the chamber. The cell was designed to optimize the counting rate (2000 cts/s at the maximum of the Cl K{alpha} emission line), while minimizing self-absorption. Example of the K{alpha} emission lines of CH{sub 3}Cl molecules is presented to illustrate the capabilities of this new instrument.

  9. Pipe support program at Pickering

    International Nuclear Information System (INIS)

    Sahazizian, L.A.; Jazic, Z.

    1997-01-01

    This paper describes the pipe support program at Pickering. The program addresses the highest priority in operating nuclear generating stations, safety. We present the need: safety, the process: managed and strategic, and the result: assurance of critical piping integrity. In the past, surveillance programs periodically inspected some systems, equipment, and individual components. This comprehensive program is based on a managed process that assesses risk to identify critical piping systems and supports and to develop a strategy for surveillance and maintenance. The strategy addresses all critical piping supports. Successful implementation of the program has provided assurance of critical piping and support integrity and has contributed to decreasing probability of pipe failure, reducing risk to worker and public safety, improving configuration management, and reducing probability of production losses. (author)

  10. Analysis of the dynamic stability of collar-stiffened pipes conveying fluid

    Science.gov (United States)

    Aldraihem, Osama J.

    2007-03-01

    The dynamic stability of a collar-stiffened pipe conveying fluid was examined by using the Euler-Bernoulli beam theory. The pipe considered consists of identical substructures, or cells, connected in an identical fashion. Each substructure, or cell, comprises a uniform pipe segment and a collar. A finite element model was developed to predict the dynamic stability of the stiffened pipe under the action of the flowing fluid. Stability maps were obtained for clamped-free collar-stiffened pipes of various design parameters. The design parameters included the arrangement and the geometry of the identical cells. The stability maps demonstrated that the collar-stiffened pipe exhibits unique stability characteristics when compared to a uniform pipe. It was found that the stable region in the stability map enlarges for the collar-stiffened pipe when compared to a uniform pipe. To give clearer insight into the pipe dynamic behavior, the dynamic response and eigenvalue branches were presented for a number of collar-stiffened pipes.

  11. Characterization of radioactive contamination inside pipes with the Pipe Explorer trademark system

    International Nuclear Information System (INIS)

    Lowry, W.

    1994-01-01

    The objective for the development of the Pipe Explorer trademark radiological characterization system is to achieve a cost effective, low risk means of characterizing gamma radioactivity on the inside surface of pipes. The unique feature of this inspection system is the use of a pneumatically inflated impermeable membrane which transports the detector into the pipe as it inverts. The membrane's internal air pressure tows the detector and tether through the pipe. This mechanism isolates the detector and its cabling from the contaminated surface, yet allows measurement of radioactive emissions which can readily penetrate the thin plastic membrane material (such as gamma and high energy beta emissions). In Phase 1, an initial survey of DOE facilities was conducted to determine the physical and radiological characteristics of piping systems. The inverting membrane deployment system was designed and extensively tested in the laboratory. A range of membrane materials was tested to evaluate their ruggedness and deployment characteristics. Two different sizes of gamma scintillation detectors were procured and tested with calibrated sources. Radiation transport modeling evaluated the measurement system's sensitivity to detector position relative to the contaminated surface, the distribution of the contamination, background gamma levels, and gamma source energy levels. In the culmination of Phase 1, a field demonstration was conducted at the Idaho National Engineering Laboratory's Idaho Chemical Processing Plant. The project is currently in transition from Phase 1 to Phase 2, where more extensive demonstrations will occur at several sites. Results to date are discussed

  12. Piping stress analysis for AP600 secondary system

    International Nuclear Information System (INIS)

    Tjahyono, Hendro

    1998-01-01

    Piping stress analysis for AP600 secondary system has been done using software PS-CAEPIPE version mainframe and CAEPIPE version PC. The loading applied to the system are statical load consist of deadweight, pressure load and thermal expansion load. Standard used in this calculation is ASME/ANSI B31.1. A piping system consists of pipes and appropriate components, such as achors, valves, pumps, flanges, etc. The parameters to be evaluated are pipe stress (psi), pipe displacements (in) and component loading (lbs). The use of support in the optimal manner is to be considered to reach a favorable condition. The allowable stress for sustained loads (death-weight and pressure) is S H (15000 psi in these cases) and for thermal load is S A (22500 psi in these cases). The allowable pipe displacement within 0.125 inches for total load. Therefore, the allowable load of components depends on the component itself. Three piping analysis packages for secondary system of AP600 have been done, those are HDS-310 (turbine building) and VYS-210 (auxiliary building). These system contain pipes with the diameter of 1 inch, 8 inches, 10 inches and 16 inches. The design pressures are in the range of 50 to 550 psi and the design temperatures are in the range of 185 deg F. The result shows that for analysis without supports, only CDS-080 is acceptable. After locating a variable support in HDS-310 and 3 rigid supports in VYS-210, all system are acceptable with the maximum pipe stress of 6533 psi, maximum displacement for sustained load of 0.069 inches and for total load of 0.635 inches

  13. Water hammer in elastic pipes

    International Nuclear Information System (INIS)

    Gale, J.; Tiselj, I.

    2002-01-01

    One dimensional two-fluid six-equation model of two-phase flow, that can be found in computer codes like RELAP5, TRAC, and CATHARE, was upgraded with additional terms, which enable modelling of the pressure waves in elastic pipes. It is known that pipe elasticity reduces the propagation velocity of the shock and other pressure waves in the piping systems. Equations that include the pipe elasticty terms are used in WAHA code, which is being developed within the WAHALoads project of 5't'h EU research program.(author)

  14. Piezoelectric properties of polymers containing bent-shape liquid crystal molecules

    Science.gov (United States)

    Diorio, N.; Varga, M.; Carif, A.; Puskas, J. E.; Fodor-Csorba, K.; Sprunt, S.; Gleeson, J. T.; Jakli, A.

    2013-03-01

    Recently, bent-core liquid crystal elastomers have shown to exhibit large values of flexoelectricity as many as 3 orders of magnitude larger than liquid crystal elastomers containing rod-shaped molecules. These unusual high responses are attributed to have piezoelectric origin. Motivated by this, in this study, two bent-core liquid crystals were used to make various types of materials; low molecular weight bent-core nematic fluid, side chain bent-core liquid crystal polymer, low molecular liquid crystal dispersed in a polyisobutylene-based thermoplastic elastomer, and side-chain bent-core elastomers. Liquid crystal elastomers combine elasticity and flexibility inherent to rubbers and the optical and electrical properties of liquid crystals, and are promising materials for applications such as electro-optics, flexible electronics and actuator technologies for biomedical applications. Most conventional liquid crystal elastomers have rod-shaped liquid crystal molecules chemically attached to a crosslinked polymer network. Converse piezoelectric responses were measured by a Mirau interferometer and the direct piezoelectric signals were studied by home-made device where the stress is provided by an audio speaker. The results will be analyzed in terms of ferroelectric clusters of the materials in the nematic phase and will be compared with other piezoelectric materials. Supported by Grants NSF-DMR -0964765 and NSF-DMR -0804878.

  15. Corrosion and deposit evaluation in large diameter pipes using radiography

    International Nuclear Information System (INIS)

    Boateng, A.

    2012-01-01

    The reliability and safety of industrial equipment in the factories and processing industries are substantially influenced by degradation processes such as corrosion, erosion, deposits and blocking of pipes. These might lead to low production, unpredictable and costly shutdowns due to repair and replacement and sometimes combined environmental pollution and risk of personnel injuries. Only periodic inspection for the integrity of pipes and equipment can reduce the risk in connection with other maintenance activities. The research explored two methods of radiographic inspection techniques, the double wall technique and the tangential radiographic technique using Ir-192 for evaluating deposits and corrosion attacks across the inner and outer walls of steel pipes with diameter greater than 150 mm with or without insulation. The application of both techniques was conducted depending on pipe diameter, wall thickness, radiation source (Ir-92) and film combination. The iridium source was positioned perpendicular with respect to the pipe axis projecting the double wall of the pipe on the plated radiographic film. With the tangential radiographic technique, the source was placed tangential to the pipe wall and because of its large diameter, the source was collimated to prevent backscatter and also to focus the beam at the target area of interest. All measurements were performed on special designed test pieces to simulate corrosion attack and deposits on industrial pipes. Pitting corrosion measurements based on Tangential Radiographic Technique were more sophisticated, and therefore magnification factor and correction were used to establish the estimated pit depth on the film. The insulating material used to conserve the thermodynamic properties of the transported media had relatively negligible attenuation coefficient compared to the concrete deposit. The two explored techniques were successful in evaluating corrosion attack and deposit on the walls of the pipe and the risk

  16. Electrically heated pipe in pipe combined with electrical submersible pumps for deepwater development

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Sidnei Guerreiro da; Euphemio, Mauro Luiz Lopes [PETROBRAS S.A., Rio de Janeiro, RJ (Brazil)

    2008-07-01

    The general trend of deep water and ultra deep water field development is the requirement of highly insulated flow lines, as flow assurance has become one of the major considerations in designing and operating the sub sea system. If not adequately considered in the design phase, it can have significant and unexpected effects to the operational costs, increasing production lost time, decreasing efficiency. In this scenario, the use of pipe in pipe flow lines, with high passive insulation and/ or active heating (called the Electrically Heated Pipe in Pipe - EHPIP), emerges as an attractive method to prevent deposition, especially of waxes and hydrates, by actively maintaining or leading the temperature of the flow line above a critical limit. Besides, the recent heavy oil discoveries in Brazil have encouraged PETROBRAS to move a step forward in the artificial lift design and operation, by the use of Electrical Submersible Pumps (ESP) installed in deep water wells. The combination of EHPIP and ESP are particularly suitable for deep water, high viscosity and long tie back systems, but also can improve oil recovery and production efficiency by allowing the operator to drop down production losses associated Flow Assurance problems. (author)

  17. Venting of gas deflagrations through relief pipes

    OpenAIRE

    Ferrara, Gabriele

    2006-01-01

    Vent devices for gas and dust explosions are often ducted to safety locations by means of relief pipes for the discharge of hot combustion products or blast waves (NFPA 68, 2002). The presence of the duct is likely to increase the severity of the explosion with respect to simply vented vessels posing a problem for the proper design of this venting configuration. The phenomenology of the vented explosion is complicated as the interaction of combustion in the duct with primary combustion in...

  18. Mechanism of selective corrosion in electrical resistance seam welded carbon steel pipe

    Energy Technology Data Exchange (ETDEWEB)

    Lopez Fajardo, Pedro; Godinez Salcedo, Jesus; Gonzalez Velasquez, Jorge L. [Instituto Politecnico Nacional, Mexico D.F., (Mexico). Escuela Superior de Ingenieria Quimica e Industrias Extractivas. Dept. de Ingenieria Metalurgica

    2009-07-01

    In this investigation the studies of the mechanism of selective corrosion in electrical resistance welded (ERW) carbon steel pipe was started. Metallographic characterizations and evaluations for inclusions were performed. The susceptibility of ERW pipe to selective corrosion in sea water (NACE 1D182, with O{sub 2} or CO{sub 2} + H{sub 2}S) was studied by the stepped potential Potentiostatic electrochemical test method in samples of 1 cm{sup 3} (ASTM G5) internal surface of the pipe (metal base-weld). The tests were looking for means for predicting the susceptibility of ERW pipe to selective corrosion, prior to placing the pipeline in service. Manganese sulfide inclusions are observed deformed by the welding process and they are close to the weld centerline. A slight decarburization at the weld line is observed, and a distinct out bent fiber pattern remains despite the post-weld seam annealing. The microstructure of the weld region consists of primarily polygonal ferrite grains mixed with small islands of pearlite. It is possible to observe the differences of sizes of grain of the present phases in the different zones. Finally, scanning electron microscopic observation revealed that the corrosion initiates with the dissolution of MnS inclusions and with small crack between the base metal and ZAC. (author)

  19. Project W-320, 241-C-106 sluicing: Piping calculations. Volume 4

    International Nuclear Information System (INIS)

    Bailey, J.W.

    1998-01-01

    This supporting document has been prepared to make the FDNW calculations for Project W-320 readily retrievable. The objective of this calculation is to perform the structural analysis of the Pipe Supports designed for Slurry and Supernate transfer pipe lines in order to meet the requirements of applicable ASME codes. The pipe support design loads are obtained from the piping stress calculations W320-27-I-4 and W320-27-I-5. These loads are the total summation of the gravity, pressure, thermal and seismic loads. Since standard typical designs are used for each type of pipe support such as Y-Stop, Guide and Anchors, each type of support is evaluated for the maximum loads to which this type of supports are subjected. These loads are obtained from the AutoPipe analysis and used to check the structural adequacy of these supports

  20. Project W-320, 241-C-106 sluicing: Piping calculations. Volume 4

    Energy Technology Data Exchange (ETDEWEB)

    Bailey, J.W.

    1998-07-24

    This supporting document has been prepared to make the FDNW calculations for Project W-320 readily retrievable. The objective of this calculation is to perform the structural analysis of the Pipe Supports designed for Slurry and Supernate transfer pipe lines in order to meet the requirements of applicable ASME codes. The pipe support design loads are obtained from the piping stress calculations W320-27-I-4 and W320-27-I-5. These loads are the total summation of the gravity, pressure, thermal and seismic loads. Since standard typical designs are used for each type of pipe support such as Y-Stop, Guide and Anchors, each type of support is evaluated for the maximum loads to which this type of supports are subjected. These loads are obtained from the AutoPipe analysis and used to check the structural adequacy of these supports.

  1. Heat pipe and method of production of a heat pipe

    International Nuclear Information System (INIS)

    Kemp, R.S.

    1975-01-01

    The heat pipe consists of a copper pipe in which a capillary network or wick of heat-conducting material is arranged in direct contact with the pipe along its whole length. Furthermore, the interior space of the tube contains an evaporable liquid for pipe transfer. If water is used, the capillary network consists of, e.g., a phosphorus band network. To avoid contamination of the interior of the heat pipe during sealing, its ends are closed by mechanical deformation so that an arched or plane surface is obtained which is in direct contact with the network. After evacuation of the interior space, the remaining opening is closed with a tapered pin. The ratio wall thickness/tube diameter is between 0.01 and 0.6. (TK/AK) [de

  2. Feed water distribution pipe replacement at Loviisa NPP

    Energy Technology Data Exchange (ETDEWEB)

    Savolainen, S.; Elsing, B. [Imatran Voima Loviisa NPP (Finland)

    1995-12-31

    Imatran Voima Oy operates two WWER-440 reactors. Unit 1 has been operating since 1977 and unit 2 since 1981. First damages of feed water distribution (FWD) pipe were observed in 1989. The FWD-pipe T-connection had suffered from severe erosion corrosion damages. Similar damages have been been found also in other WWER-440 type NPPs. In 1989 the nozzles of the steam generator YB11 were inspected. No signs of the damages or signs of erosion were detected. The first damaged nozzles were found in 1992 in steam generators of both units. In 1992 it was started studying different possibilities to either repair or replace the damaged FWD-pipes. Due to the difficult conditions for repairing the damaged nozzles it was decided to study different FWD-pipe constructions. In 1991 two new feedwater distributors had been implemented at Dukovany NPP designed by Vitckovice company. Additionally OKB Gidropress had presented their design for new collector. In spring 1994 all the six steam generators of Rovno NPP unit 1 were replaced with FWD-pipes designed by OKB Gidropress. After the implementation an experimental program with the new systems was carried out. Due to the successful experiments at Rovno NPP Unit 1 it was decided to implement `Gidropress solution` during 1994 refueling outage into the steam generator YB52 at Loviisa 2. The object of this paper is to discuss the new FWD-pipe and its effects on the plant safety during normal and accident conditions. (orig.).

  3. Deformation mechanisms of bent Si nanowires governed by the sign and magnitude of strain

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Lihua, E-mail: wlh@bjut.edu.cn, E-mail: xdhan@bjut.edu.cn, E-mail: j.zou@uq.edu.au [Beijing Key Lab of Microstructure and Property of Advanced Material, Institute of Microstructure and Properties of Advanced Materials, Beijing University of Technology, Beijing 100124 (China); Materials Engineering, The University of Queensland, Brisbane, QLD 4072 (Australia); Kong, Deli; Xin, Tianjiao; Shu, Xinyu; Zheng, Kun; Xiao, Lirong; Sha, Xuechao; Lu, Yan; Han, Xiaodong, E-mail: wlh@bjut.edu.cn, E-mail: xdhan@bjut.edu.cn, E-mail: j.zou@uq.edu.au [Beijing Key Lab of Microstructure and Property of Advanced Material, Institute of Microstructure and Properties of Advanced Materials, Beijing University of Technology, Beijing 100124 (China); Zhang, Ze [Department of Materials Science, Zhejiang University, Hangzhou 310008 (China); Zou, Jin, E-mail: wlh@bjut.edu.cn, E-mail: xdhan@bjut.edu.cn, E-mail: j.zou@uq.edu.au [Materials Engineering, The University of Queensland, Brisbane, QLD 4072 (Australia); Centre for Microscopy and Microanalysis, The University of Queensland, Brisbane, QLD 4072 (Australia)

    2016-04-11

    In this study, the deformation mechanisms of bent Si nanowires are investigated at the atomic scale with bending strain up to 12.8%. The sign and magnitude of the applied strain are found to govern their deformation mechanisms, in which the dislocation types (full or partial dislocations) can be affected by the sign (tensile or compressive) and magnitude of the applied strain. In the early stages of bending, plastic deformation is controlled by 60° full dislocations. As the bending increases, Lomer dislocations can be frequently observed. When the strain increases to a significant level, 90° partial dislocations induced from the tensile surfaces of the bent nanowires are observed. This study provides a deeper understanding of the effect of the sign and magnitude of the bending strain on the deformation mechanisms in bent Si nanowires.

  4. Spectral tuning of a locally bent microfiber taper interferometer with a nanosized liquid crystal overlay.

    Science.gov (United States)

    Luo, Haimei; Wang, Changjing; Ji, Yinghua; Yuan, Wen; Zhang, Guoping; Wang, Yifan; Hong, Zehua; Wang, Xianping

    2016-09-10

    In this paper, the tuning characteristics of locally bent microfiber taper covered with a nanosized high-refractive-index liquid crystal (LC) layer under different temperatures and electric field intensities have been theoretically analyzed and experimentally investigated. A locally bent microfiber taper interferometer with a waist diameter of ∼3.72  μm is fabricated by using the flame brushing technique, followed by bending the transition region of the taper to form a modal interferometer and later by placing a ∼200  nm LC layer over the uniform taper waist region. Experimental results indicate that a high-efficiency thermal or electric tuning of an LC-coated locally bent microfiber taper interferometer could be achieved. This suggests a potential application of this device as tunable all-fiber photonic devices, such as filters, modulators, and sensing elements.

  5. Bent silica nanosheets directed from crystalline templates controlled by proton donors

    International Nuclear Information System (INIS)

    Matsukizono, Hiroyuki; Jin, Ren-Hua

    2011-01-01

    Linear poly(ethyleneimine) (LPEI) is easily crystallizable with the formation of various morphologies in the aqueous medium when its hot solution cooled down to room temperature. Herein, we prepared a series of crystalline precipitates of LPEI grown in the presence of proton donating compounds such as Tris–HCl, tartaric acid, amino acids, and used the precipitates in directing silica deposition. Since the proton donating compounds can mediate the pH with donating the proton to LPEI, the crystallization of LPEI evidently depended on the concentrations of the proton donating compounds. It was found that the precipitates grown in the conditions of the pH ranged 8.2–8.5 directed well-controlled bent nanosheet of silica/LPEI composites. The bent nanosheet is constructed by multi-layered structures with a little slippage between layers. The bent nanosheet silica has slit-like pore with ca. 10 nm width.

  6. Application of spherically bent crystals spectrometer to X-ray diagnosis

    International Nuclear Information System (INIS)

    Liu Lifeng; Xiao Shali; Wang Hongjian; Shi Jun; Qian Jiayu; Liu Shenye; Wei Minxi; Chen Bolun

    2010-01-01

    In order to diagnose X-ray emitted from the plasma, a spherically bent crystals spectrometer was developed based on the X-ray Bragg diffraction theory. In the experiment, the dispersive element of crystal analyzer was quartz, the bent radius was 250 mm and the range of Bragg angle of the crystal was 30 degree to 67.5 degree. The X-ray film, as its principal detector, obtained spectra information which had an effective area of 10 mm x 50 mm. The experiment was carried out at the anode accelerator. The detector obtained the X-ray spectra information of the K-shell Ti spectra. By the analysis of spectra information, the spectral resolution of spherically bent quartz crystals can be achieved for more than 1000, and the spectral passband is 0.43 eV. (authors)

  7. Mechanical Behaviour of Lined Pipe

    NARCIS (Netherlands)

    Hilberink, A.

    2011-01-01

    Installing lined pipe by means of the reeling installation method seems to be an attractive combination, because it provides the opportunity of eliminating the demanding welds from the critical time offshore and instead preparing them onshore. However, reeling of lined pipe is not yet proven

  8. Flexible ultrasonic pipe inspection apparatus

    Science.gov (United States)

    Jenkins, Charles F.; Howard, Boyd D.

    1998-01-01

    A flexible, modular ultrasonic pipe inspection apparatus, comprising a flexible, hollow shaft that carries a plurality of modules, including at least one rotatable ultrasonic transducer, a motor/gear unit, and a position/signal encoder. The modules are connected by flexible knuckle joints that allow each module of the apparatus to change its relative orientation with respect to a neighboring module, while the shaft protects electrical wiring from kinking or buckling while the apparatus moves around a tight corner. The apparatus is moved through a pipe by any suitable means, including a tether or drawstring attached to the nose or tail, differential hydraulic pressure, or a pipe pig. The rotational speed of the ultrasonic transducer and the forward velocity of the apparatus are coordinated so that the beam sweeps out the entire interior surface of the pipe, enabling the operator to accurately assess the condition of the pipe wall and determine whether or not leak-prone corrosion damage is present.

  9. Energy funneling in a bent chain of Morse oscillators with long-range coupling

    DEFF Research Database (Denmark)

    Larsen, Peter Ulrik Vingaard; Christiansen, Peter Leth; Bang, Ole

    2004-01-01

    A bent chain of coupled Morse oscillators with long-range dispersive interaction is considered. Moving localized excitations may be trapped in the bending region. Thus chain geometry acts like an impurity. An energy funneling effect is observed in the case of random initial conditions.......A bent chain of coupled Morse oscillators with long-range dispersive interaction is considered. Moving localized excitations may be trapped in the bending region. Thus chain geometry acts like an impurity. An energy funneling effect is observed in the case of random initial conditions....

  10. CO2 laser ablation of bent optical fibers for sensing applications

    International Nuclear Information System (INIS)

    Lévesque, L; Jdanov, V

    2011-01-01

    A procedure for the fabrication of a fiber optic sensor involving CO 2 laser ablation at λ = 10.6 µm is proposed. A basic system to achieve optical fiber bending and material processing on a single mode optical fiber is described and it is demonstrated that an optical fiber can be bent at a very precise angle by focusing a CO 2 beam locally near the glass cladding surface until it reaches melting temperature. A method is also described for removing material at the apex of a bent fiber to obtain a smooth and well flattened plane surface that is suitable for optical fiber sensing

  11. Possibility of high efficient beam extraction from the CERN SPS with a bent crystal. Simulation results

    Energy Technology Data Exchange (ETDEWEB)

    Scandale, W. [CERN, European Organization for Nuclear Research, CH-1211 Geneva 23 (Switzerland); Laboratoire de l' AccelerateurLineaire (LAL), Universite Paris SudOrsay, Orsay (France); INFN Sezione di Roma, Piazzale Aldo Moro 2, 00185 Rome (Italy); Kovalenko, A.D.; Taratin, A.M. [Joint Institute for Nuclear Research, 141980 Dubna, Moscow Region (Russian Federation)

    2017-03-11

    The extraction of the SPS beam of 270 GeV/c protons assisted by a bent crystal was studied by simulation. Two methods for delivering the SPS beam onto a crystal were considered: transverse diffusion and orbit bump of the beam. It was shown that the main condition for high efficient beam extraction with a bent crystal, which is a small divergence of the incident beam, can be fulfilled. Extraction efficiency up to 99% can be reached for both methods of the beam delivering. The irradiation of the electrostatic septum wires during the beam extraction can be considerably reduced.

  12. Fra rød stue til åbent plan

    DEFF Research Database (Denmark)

    Linde-Bech, Thomas Vestergaard; Hamilton, Stine Del Pin

    2017-01-01

    Indretning i åbent plan i moderne børnehaver påvirker børnenes leg, da de er præget af konstant tilgængelighed og forsøg på afgrænsning.......Indretning i åbent plan i moderne børnehaver påvirker børnenes leg, da de er præget af konstant tilgængelighed og forsøg på afgrænsning....

  13. Dual Symmetry in Bent-Core Liquid Crystals and Unconventional Superconductors

    Directory of Open Access Journals (Sweden)

    Vladimir Lorman

    2010-01-01

    Full Text Available We extend the Landau theory of bent-core mesophases and d-wave high-Tc superconductors by considering additional secondary pseudo-proper order parameters. These systems exhibit a remarkable analogy relating their symmetry groups, lists of phases, and an infinite set of physical tensors. This analogy lies upon an internal dual structure shared by the two theories. We study the dual operator transforming rotations into translations in liquid crystals, and gauge symmetries into rotations in superconductors. It is used to classify the bent-core line defects, and to analyze the electronic gap structure of lamellar d-wave superfluids.

  14. Deflection of high energy channeled charged particles by elastically bent silicon single crystals

    International Nuclear Information System (INIS)

    Gibson, W.M.; Kim, I.J.; Pisharodoy, M.; Salman, S.M.; Sun, C.R.; Wang, G.H.; Wijayawardana, R.; Forster, J.S.; Mitchell, I.V.; Baker, S.I.; Carrigan, R.A. Jr.; Toohig, T.E.; Avdeichikov, V.V.; Ellison, J.A.; Siffert, P.

    1984-01-01

    An experiment has been carried out to observe the deflection of charged particles by planar channeling in bent single crystals of silicon for protons with energy up to 180 GeV. Anomolous loss of particles from the center point of a three point bending apparatus was observed at high incident particle energy. This effect has been exploited to fashion a 'dechanneling spectrometer' to study dechanneling effects due to centripital displacement of channeled particle trajectories in a bent crystal. The bending losses generally conform to the predictions of calculations based on a classical model. (orig.)

  15. Application of LBB to high energy piping systems in operating PWR

    Energy Technology Data Exchange (ETDEWEB)

    Swamy, S.A.; Bhowmick, D.C. [Westinghouse Nuclear Technology Division, Pittsburgh, PA (United States)

    1997-04-01

    The amendment to General Design Criterion 4 allows exclusion, from the design basis, of dynamic effects associated with high energy pipe rupture by application of leak-before-break (LBB) technology. This new approach has resulted in substantial financial savings to utilities when applied to the Pressurized Water Reactor (PWR) primary loop piping and auxiliary piping systems made of stainless steel material. To date majority of applications pertain to piping systems in operating plants. Various steps of evaluation associated with the LBB application to an operating plant are described in this paper.

  16. Remotely controlled repair of piping at Douglas Point

    International Nuclear Information System (INIS)

    Conrath, J.J.

    1983-06-01

    The 200 MWe Douglas Point Nuclear Generating Station which started operation in 1966 was Canada's first commercial nuclear power plant. In 1977, after 11 years of operation, leakage of heavy water was detected and traced to the Moderator Piping System (pipe sizes 19 mm to 76 mm) located in a vault below the reactor where the radiation fields during shutdown ranged up to 5000 R/Hr. Inspection using remotely operated TV cameras showed that a 'U' bolt clamp support had worn through the wall of one pipe and resulted in the leakage and also that wear was occurring on other pipes. An extensive repair plan was subsequently undertaken in the form of a joint venture of the designer-owner Atomic Energy of Canada Limited, and the builder-operator, Ontario Hydro. This paper describes the equipment and procedures used in remotely controlled repairs at Douglas Point

  17. Life cycle guideline of petrochemical plant underground piping system

    Directory of Open Access Journals (Sweden)

    Shih Jeng-Ywan

    2017-01-01

    Full Text Available According to statistics of petrochemical plant disaster, the type of underground pipeline leakage is the highest proportion, for example, Kaohsiung gas explosion in 2014 is a typical case. Therefore, improvement strategy of petrochemical plant underground piping system from both engineering and management becomes an important issue. Through reviewing regulations as well as surveying questionnaire, including kinds of piping materials, 3D drawing files, operation procedures, information sharing, etc., the findings show lack contact of integrated management with engineering executive and insufficient technical requirements are major defects. Overviewing current problems of domestic petrochemical plant underground piping system management, and comparing to international criteria and specifications, this research focuses on the of piping design, construction, operations, maintenance, and inspection. Then management procedures and engineering technical feasibility strategies are suggested. In addition, the proposed life cycle guideline in order to reduce the disaster incidence of petrochemical plant underground pipelines.

  18. Modeling of the effect of plasticity on the response of pipe systems to internal explosions

    NARCIS (Netherlands)

    Smeulers, J.P.M.; Pape, G.; Ligterink, N.E.

    2012-01-01

    Pipe systems that are used in the process industry may occasionally be subjected to internal deflagration and detonation waves. In those cases the design of the pipe system should be explosion resistant or even explosion proof. The usual design rule for the analysis of the mechanical response is

  19. 49 CFR 192.113 - Longitudinal joint factor (E) for steel pipe.

    Science.gov (United States)

    2010-10-01

    ... SAFETY TRANSPORTATION OF NATURAL AND OTHER GAS BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Pipe Design... design formula in § 192.105 is determined in accordance with the following table: Specification Pipe... Electric-fusion-welded 1.00 ASTM A 691 Electric-fusion-welded 1.00 API 5 L Seamless 1.00 Electric...

  20. OTEC Cold Water Pipe-Platform Subsystem Dynamic Interaction Validation

    Energy Technology Data Exchange (ETDEWEB)

    Varley, Robert [Lockheed Martin Corporation, Manassas, VA (United States); Halkyard, John [John Halkyard and Associates, Houston, TX (United States); Johnson, Peter [BMT Scientific Marine Services, Inc., Houston, TX (United States); Shi, Shan [Houston Offshore Engineering, Houston, TX (United States); Marinho, Thiago [Federal Univ. of Rio de Janeiro (Brazil). LabOceano

    2014-05-09

    A commercial floating 100-megawatt (MW) ocean thermal energy conversion (OTEC) power plant will require a cold water pipe (CWP) with a diameter of 10-meter (m) and length of up to 1,000 m. The mass of the cold water pipe, including entrained water, can exceed the mass of the platform supporting it. The offshore industry uses software-modeling tools to develop platform and riser (pipe) designs to survive the offshore environment. These tools are typically validated by scale model tests in facilities able to replicate real at-sea meteorological and ocean (metocean) conditions to provide the understanding and confidence to proceed to final design and full-scale fabrication. However, today’s offshore platforms (similar to and usually larger than those needed for OTEC applications) incorporate risers (or pipes) with diameters well under one meter. Secondly, the preferred construction method for large diameter OTEC CWPs is the use of composite materials, primarily a form of fiber-reinforced plastic (FRP). The use of these material results in relatively low pipe stiffness and large strains compared to steel construction. These factors suggest the need for further validation of offshore industry software tools. The purpose of this project was to validate the ability to model numerically the dynamic interaction between a large cold water-filled fiberglass pipe and a floating OTEC platform excited by metocean weather conditions using measurements from a scale model tested in an ocean basin test facility.

  1. Determination of leakage areas in nuclear piping

    International Nuclear Information System (INIS)

    Keim, E.

    1997-01-01

    For the design and operation of nuclear power plants the Leak-Before-Break (LBB) behavior of a piping component has to be shown. This means that the length of a crack resulting in a leak is smaller than the critical crack length and that the leak is safely detectable by a suitable monitoring system. The LBB-concept of Siemens/KWU is based on computer codes for the evaluation of critical crack lengths, crack openings, leakage areas and leakage rates, developed by Siemens/KWU. In the experience with the leak rate program is described while this paper deals with the computation of crack openings and leakage areas of longitudinal and circumferential cracks by means of fracture mechanics. The leakage areas are determined by the integration of the crack openings along the crack front, considering plasticity and geometrical effects. They are evaluated with respect to minimum values for the design of leak detection systems, and maximum values for controlling jet and reaction forces. By means of fracture mechanics LBB for subcritical cracks has to be shown and the calculation of leakage areas is the basis for quantitatively determining the discharge rate of leaking subcritical through-wall cracks. The analytical approach and its validation will be presented for two examples of complex structures. The first one is a pipe branch containing a circumferential crack and the second one is a pipe bend with a longitudinal crack

  2. Determination of leakage areas in nuclear piping

    Energy Technology Data Exchange (ETDEWEB)

    Keim, E. [Siemens/KWU, Erlangen (Germany)

    1997-04-01

    For the design and operation of nuclear power plants the Leak-Before-Break (LBB) behavior of a piping component has to be shown. This means that the length of a crack resulting in a leak is smaller than the critical crack length and that the leak is safely detectable by a suitable monitoring system. The LBB-concept of Siemens/KWU is based on computer codes for the evaluation of critical crack lengths, crack openings, leakage areas and leakage rates, developed by Siemens/KWU. In the experience with the leak rate program is described while this paper deals with the computation of crack openings and leakage areas of longitudinal and circumferential cracks by means of fracture mechanics. The leakage areas are determined by the integration of the crack openings along the crack front, considering plasticity and geometrical effects. They are evaluated with respect to minimum values for the design of leak detection systems, and maximum values for controlling jet and reaction forces. By means of fracture mechanics LBB for subcritical cracks has to be shown and the calculation of leakage areas is the basis for quantitatively determining the discharge rate of leaking subcritical through-wall cracks. The analytical approach and its validation will be presented for two examples of complex structures. The first one is a pipe branch containing a circumferential crack and the second one is a pipe bend with a longitudinal crack.

  3. Computer graphics in piping structural engineering

    International Nuclear Information System (INIS)

    Revesz, Z.

    1985-01-01

    Computer graphics in piping structural engineering is gaining in popularity. The large number of systems, the growing complexity of the load cases and structure models require human assimilation of large amounts of data. An effort has been made to enlighten evaluation of numerical data and visualize as much of it as possible, thus eliminating a source of error and accelerating analysis/reporting. The product of this effort is PAID, the Piping Analysis and Interactive Design software. While developing PAID, interest has been focused on the acceleration of the work done mainly by PIPESTRESS. Some installed and tested capabilities of PAID are presented in this paper. Examples are given from the graphic output in report form and the conversation necessary to get such is demonstrated. (orig.)

  4. SHAM: High-level seismic tests of piping at the HDR

    International Nuclear Information System (INIS)

    Kot, C.A.; Srinivasan, M.G.; Hsieh, B.J.; Malcher, L.; Schrammel, D.; Steinhilber, H.; Costello, J.F.

    1988-01-01

    As part of the second phase of vibrational/earthquake investigations at the HDR (Heissdampfreaktor) Test Facility in Kahl/Main, FRG, high-level simulated seismic tests (SHAM) were performed during April--May 1988 on the VKL (Versuchskreislauf) in-plant piping system with two servohydraulic actuators, each capable of generating 40 tons of force. The purpose of these experiments was to study the behavior of piping subjected to seismic excitation levels that exceed design levels manifold and may result in failure/plastification of pipe supports and pipe elements, and to establish seismic margins for piping and pipe supports. The performance of six different dynamic pipe support systems was compared in these tests and the response, operability, and fragility of dynamic supports and of a typical US gate valve were investigated. Data obtained in the tests are used to validate analysis methods. Very preliminary evaluations lead to the observation that, in general, failures of dynamic supports (in particular snubbers) occur only at load levels that substantially exceed the design capacity. Pipe strains at load levels exceeding the design level threefold are quite small, and even when exceeding the design level eightfold are quite tolerable. Hence, under seismic loading, even at extreme levels and in spite of multiple support failures, pipe failure is unlikely. 5 refs., 16 figs

  5. Report of the US Nuclear Regulatory Commission Piping Review Committee. Volume 5. Summary - Piping Review Committee conclusions and recommendations

    International Nuclear Information System (INIS)

    1985-04-01

    This document summarizes a comprehensive review of NRC requirements for Nuclear Piping by the US NRC Piping Review Committee. Four topical areas, addressed in greater detail in Volumes 1 through 4 of this report, are included: (1) Stress Corrosion Cracking in Piping of Boiling Water Reactor Plants; (2) Evaluation of Seismic Design; (3) Evaluation of Potential for Pipe Breaks; and (4) Evaluation of Other Dynamic Loads and Load Combinations. This volume summarizes the major issues, reviews the interfaces, and presents the Committee's conclusions and recommendations for updating NRC requirements on these issues. This report also suggests research or other work that may be required to respond to issues not amenable to resolution at this time

  6. Solar chemical heat pipe

    International Nuclear Information System (INIS)

    Levy, M.; Levitan, R.; Rosin, H.; Rubin, R.

    1991-08-01

    The performance of a solar chemical heat pipe was studied using CO 2 reforming of methane as a vehicle for storage and transport of solar energy. The endothermic reforming reaction was carried out in an Inconel reactor, packed with a Rh catalyst. The reactor was suspended in an insulated box receiver which was placed in the focal plane of the Schaeffer Solar Furnace of the Weizman Institute of Science. The exothermic methanation reaction was run in a 6-stage adiabatic reactor filled with the same Rh catalyst. Conversions of over 80% were achieved for both reactions. In the closed loop mode the products from the reformer and from the metanator were compressed into separate storage tanks. The two reactions were run either separately or 'on-line'. The complete process was repeated for over 60 cycles. The overall performance of the closed loop was quite satisfactory and scale-up work is in progress in the Solar Tower. (authors). 35 refs., 2 figs

  7. Pipework design and operation

    International Nuclear Information System (INIS)

    Anon.

    1985-01-01

    This book presents the proceedings of a conference dedicated to the design and operation of pipework in all its aspects, involving both metallic and non-metallic materials. Topics considered include a study of single mitre pipe bends using the finite element method; tests to failure of GRP pipe bends under in-plane flexural loading; finite element stress analysis of an equal diameter branch pipe intersection subjected to internal pressure and in-plane moment loadings; finite element stress analysis of extruded outlet tee junctions; design of pipework on the British PWR; a review of advanced remanent life methods for pipes operating in the creep range; pipe whip analysis and design; damping values for piping systems; pipework snubbers based on electro-rheological fluids; and the seismic design of piping systems in the flexible range

  8. Circus, software for computation of flow induced vibrations in piping system. General purpose

    International Nuclear Information System (INIS)

    Seligmann, D.

    1996-11-01

    This paper is a presentation of the code CIRCUS version 2. CIRCUS deals with the hydraulic, acoustic and vibratory behaviour of piping systems under acoustic loads. CIRCUS first computes permanent mean-flow, and associated acoustic loads. It then determines the acoustic and vibration response along the piping system. The CIRCUS software is used at EDF to check the design of piping system and to investigate solutions in case of damage or troubleshooting. (author)

  9. Experimental Investigation on Corrosion Effect on Mechanical Properties of Buried Metal Pipes

    OpenAIRE

    Hou, Yingbo; Lei, Deqing; Li, Shujin; Yang, Wei; Li, Chun-Qing

    2016-01-01

    Corrosion has been found to be the most predominant cause for failures of buried metal pipes. A review of published literature on pipe corrosion reveals that little research has been undertaken on the effect of corrosion on mechanical properties of pipe materials and almost no research has been conducted on corrosion effect on fracture toughness. The intention of this paper is to present a comprehensive test program designed to investigate the effect of corrosion on mechanical properties of m...

  10. Analysis of Geometrical Relationships and Friction Losses in Small-Diameter Lay-Flat Polyethylene Pipes

    OpenAIRE

    Provenzano, Giuseppe; Alagna, Vincenzo; Autovino, Dario; Manzano Juarez, Juan; Rallo, Giovanni

    2016-01-01

    [EN] The use of lay-flat polyethylene pipes to irrigate horticultural crops has been receiving widespread attention in the last decade, due to the significant improvements in their hydraulic performance, their potentially high application efficiency, and their limited installation costs. However, even if hydraulic design procedures for conventional microirrigation systems are fairly well established, there is still the need to know how different pipe-wall thicknesses of lay-flat pipes can aff...

  11. Film behaviour of vertical gas-liquid flow in a large diameter pipe

    OpenAIRE

    Zangana, Mohammed Haseeb Sedeeq

    2011-01-01

    Gas-liquid flow commonly occurs in oil and gas production and processing system. Large diameter vertical pipes can reduce pressure drops and so minimize operating costs. However, there is a need for research on two-phase flow in large diameter pipes to provide confidence to designers of equipments such as deep water risers. In this study a number of experimental campaigns were carried out to measure pressure drop, liquid film thickness and wall shear in 127mm vertical pipe. Total pressur...

  12. Suppression of surface effect by using bent-perfect-crystal monochromator in residual strain scanning

    Czech Academy of Sciences Publication Activity Database

    Vrána, Miroslav; Mikula, Pavol

    490/491, - (2005), s. 234-238 ISSN 0255-5476 R&D Projects: GA ČR GA202/03/0891; GA AV ČR KSK1010104 Institutional research plan: CEZ:AV0Z1048901 Keywords : neutron diffraction * residual strain scanning * bent monochromator Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.399, year: 2005

  13. Evaluation of a timber column bent substructure after more than 60 years in-service

    Science.gov (United States)

    James P. Wacker; Xiping Wang; Douglas R. Rammer; William J. Nelson

    2011-01-01

    This paper describes both the field evaluation and laboratory testing of two timber-column-bent bridge substructures. These substructures served as intermediate pier supports for the East Deer Park Drive Bridge located in Gaithersburg, Maryland. A field evaluation of the bridge substructure was conducted in September 2008. Nondestructive testing was performed with a...

  14. Bent crystals in Laue geometry: dynamical focusing of a polychromatic incident beam

    Czech Academy of Sciences Publication Activity Database

    Mocella, V.; Guigay, J. P.; Hrdý, Jaromír; Ferrero, C.; Hoszowska, J.

    2004-01-01

    Roč. 37, - (2004), s. 941-946 ISSN 0021-8898 Institutional research plan: CEZ:AV0Z1010921 Keywords : polychromatic focusing * bent Laue crystals * dynamical diffraction * optics Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 3.534, year: 2004

  15. Bent-shaped liquid crystals based on 4-substituted 3-hydroxybenzoic acid central core

    Czech Academy of Sciences Publication Activity Database

    Kohout, M.; Kozmík, V.; Slabochová, M.; Tůma, J.; Svoboda, J.; Novotná, Vladimíra; Pociecha, D.

    2015-01-01

    Roč. 42, č. 1 (2015), s. 87-103 ISSN 0267-8292 R&D Projects: GA ČR GA13-14133S Institutional support: RVO:68378271 Keywords : liquid crystals * bent-shaped mesogens * hydroxybenzoic acid Subject RIV: JJ - Other Materials Impact factor: 2.244, year: 2015

  16. The elusive thermotropic biaxial nematic phase in rigid bent-core ...

    Indian Academy of Sciences (India)

    Abstract. The biaxial nematic liquid crystalline phase was predicted several decades ago. Several vigorous attempts to find it in various systems resulted in mis-identifications. The results of X-ray diffraction and optical texture studies of the phases exhibited by rigid bent-core molecules derived from 2 ...

  17. Note on the glide of a bird with wings bent downwards

    NARCIS (Netherlands)

    Sparenberg, J. A.

    This note considers the influence of the bending down of the wings of a bird on the performance of its glide. The induced drag of bent wings is compared with the induced drag of a corresponding straight wing. Numerical results are given.

  18. Photosensitive bent-core liquid crystals based on methyl substituted 3-hydroxybenzoic acid.

    Czech Academy of Sciences Publication Activity Database

    Kohout, M.; Alaasar, M.; Poryvai, A.; Novotná, Vladimíra; Poppe, S.; Tschierske, C.; Svoboda, J.

    2017-01-01

    Roč. 7, č. 57 (2017), s. 35805-35813 ISSN 2046-2069 R&D Projects: GA ČR GA16-12150S Institutional support: RVO:68378271 Keywords : liquid crystals * photosensitivity * bent-core liquid crystals * 3-hydroxybenzoic acid Subject RIV: JJ - Other Materials OBOR OECD: Nano-materials (production and properties) Impact factor: 3.108, year: 2016

  19. Laterally substituted symmetric and nonsymmetric salicylideneimine-based bent-core mesogens

    Directory of Open Access Journals (Sweden)

    Sonja Findeisen-Tandel

    2012-01-01

    Full Text Available Bent-core mesogens have gained considerable importance due to their ability to form new mesophases with unusual properties. Relationships between the chemical structure of bent-core molecules and the type and physical properties of the formed mesophases are relatively unknown in detail and differ strongly from those known for calamitic liquid crystals. In this paper symmetric and nonsymmetric five-ring salicylideneaniline-based bent-core mesogens are presented, and the effect of lateral substituents attached at the outer phenyl rings (F, Cl, Br or the central phenyl ring (CH3 on the liquid-crystalline behaviour and on the physical properties is studied. Corresponding benzylideneaniline-based compounds were additionally prepared in order to study the influence of the intramolecular hydrogen bond. The occurring mesophases were investigated by differential scanning calorimetry, polarising microscopy, X-ray diffraction and dielectric and electro-optical measurements. The paper reports on new findings with respect to the structure–property relationships of bent-core mesogens. On one hand, the disruptive effect of laterally substituted halogen atoms, F, Cl and Br, on the mesophase behaviour of three isomeric series was much lower than expected. On the other hand, an increase of the clearing temperature by 34 K was observed, caused by small lateral substituents. The electro-optical behaviour, especially the type of polar switching and corresponding molecular movements, is sensitive to variations in the molecular structure.

  20. 49 CFR 192.55 - Steel pipe.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Steel pipe. 192.55 Section 192.55 Transportation... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Materials § 192.55 Steel pipe. (a) New steel pipe is... in accordance with paragraph (c) or (d) of this section. (b) Used steel pipe is qualified for use...

  1. 49 CFR 192.59 - Plastic pipe.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Plastic pipe. 192.59 Section 192.59 Transportation... BY PIPELINE: MINIMUM FEDERAL SAFETY STANDARDS Materials § 192.59 Plastic pipe. (a) New plastic pipe... specification; and (2) It is resistant to chemicals with which contact may be anticipated. (b) Used plastic pipe...

  2. 49 CFR 192.281 - Plastic pipe.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Plastic pipe. 192.281 Section 192.281... Plastic pipe. (a) General. A plastic pipe joint that is joined by solvent cement, adhesive, or heat fusion may not be disturbed until it has properly set. Plastic pipe may not be joined by a threaded joint or...

  3. Determination of the pipe stemming load

    International Nuclear Information System (INIS)

    Cowin, S.C.

    1979-01-01

    A mechanical model for the emplacement pipe system is developed. The model is then employed to determine the force applied to the surface collar of the emplacement pipe, the pipe-stemming load, and the stress along the emplacement pipe as a function of stemming height. These results are presented as integrals and a method for their numerical integration is given

  4. Stresses in a curved pipe subject to an in-plane bending moment

    International Nuclear Information System (INIS)

    Hofmann, E.; Heeschen, U.

    1979-01-01

    The design of the KWU-primary component supports is mainly defined by the loads of the postulated pipe breaks. To estimate the maximum loading of a component support it is necessary to know the maximum in-plane bending moment (opening and closing) that can be transmitted by a pipe bend. Another reason for such information is that the displacements and distortions of the components cause higher stresses in elbows than in straight pipes. With a detailed knowledge of the deformation characteristic of a pipe bend an integrity analysis could be done without an expensive plastic system analysis. With this purpose in mind experiments were performed with straight pipes and pipe bends of different dimensions subject to in-plane bending moments. The experimental results give the ratio between the maximum transmittable moment of a pipe bend to that of a straight pipe or, the distortion of the end cross-sections and the flattening of the elbow cross-section. An attempt is made to derive simple expressions for estimating the behaviour at pipe elbows. Parallel to the experiments calculations were done for the straight pipe and elbow with a finite difference code with plastic capabilities. The results of the experiment and calculation are compared with the formulas of the ASME-Code section III subjection NB. (orig.)

  5. Evaluation of cold bending and mechanical properties of helical (SAWH) and longitudinal (SAWL) seam pipes

    Energy Technology Data Exchange (ETDEWEB)

    Batista, Gilmar Zacca; Sanandres, Simon Ricardo [PETROBRAS, Rio de Janeiro, RJ (Brazil). Pipeline Engineering Division; Pinto, Percy Saavedra; Mello, Marcelo [Tubos Soldados Atlantico, Sao Paulo, SP (Brazil)

    2009-07-01

    The present work is a part of a comprehensive program that aims to evaluate the helical seam pipe application in pipeline construction and compare with the traditional longitudinal seam pipe that have been used in Brazil. One of the biggest concerns is the cold bending process once the Brazilian land profile is very sinuous, different than other countries where helical seam pipes have been used successfully. At this work, two pipes were used, one helical seam and one longitudinal seam, both API 5L X70 with 28 inch of diameter and 0.469 inch wall thickness. The results of cold bending tests comparing both types of pipe and the mechanical properties from the straight pipe with the bend section are shown. The research methodology includes dimensional analysis, microstructural evaluation and mechanical tests that were performed on the straight pipe and bend areas. The cold bending parameters used to obtain a bend according the design and construction standards requirements are also presented. The results showed that the cold bending process produces a helical seam pipe bend with the most critical radius allowed by the standards, without presenting any evidence of wrinkles, out-of-roundness above the limits or any type of mechanical damage. Both pipes tested met the standards requirements in terms of bending and mechanical properties. The results of this study provide technical information for future helical seam pipe application in Brazil. (author)

  6. Pulsed Eddy Current Sensing for Critical Pipe Condition Assessment.

    Science.gov (United States)

    Ulapane, Nalika; Alempijevic, Alen; Vidal Calleja, Teresa; Valls Miro, Jaime

    2017-09-26

    Pulsed Eddy Current (PEC) sensing is used for Non-Destructive Evaluation (NDE) of the structural integrity of metallic structures in the aircraft, railway, oil and gas sectors. Urban water utilities also have extensive large ferromagnetic structures in the form of critical pressure pipe systems made of grey cast iron, ductile cast iron and mild steel. The associated material properties render NDE of these pipes by means of electromagnetic sensing a necessity. In recent years PEC sensing has established itself as a state-of-the-art NDE technique in the critical water pipe sector. This paper presents advancements to PEC inspection in view of the specific information demanded from water utilities along with the challenges encountered in this sector. Operating principles of the sensor architecture suitable for application on critical pipes are presented with the associated sensor design and calibration strategy. A Gaussian process-based approach is applied to model a functional relationship between a PEC signal feature and critical pipe wall thickness. A case study demonstrates the sensor's behaviour on a grey cast iron pipe and discusses the implications of the observed results and challenges relating to this application.

  7. Fracture behavior of short circumferentially surface-cracked pipe

    International Nuclear Information System (INIS)

    Krishnaswamy, P.; Scott, P.; Mohan, R.

    1995-11-01

    This topical report summarizes the work performed for the Nuclear Regulatory Comniission's (NRC) research program entitled ''Short Cracks in Piping and Piping Welds'' that specifically focuses on pipes with short, circumferential surface cracks. The following details are provided in this report: (i) material property deteminations, (ii) pipe fracture experiments, (iii) development, modification and validation of fracture analysis methods, and (iv) impact of this work on the ASME Section XI Flaw Evaluation Procedures. The material properties developed and used in the analysis of the experiments are included in this report and have been implemented into the NRC's PIFRAC database. Six full-scale pipe experiments were conducted during this program. The analyses methods reported here fall into three categories (i) limit-load approaches, (ii) design criteria, and (iii) elastic-plastic fracture methods. These methods were evaluated by comparing the analytical predictions with experimental data. The results, using 44 pipe experiments from this and other programs, showed that the SC.TNP1 and DPZP analyses were the most accurate in predicting maximum load. New Z-factors were developed using these methods. These are being considered for updating the ASME Section XI criteria

  8. Effect of pipe sags on wastewater collection system performance.

    Science.gov (United States)

    Sever, V Firat; Foust, Henry

    2011-04-01

    Sagging of pipelines is a common problem in centralized wastewater collection systems. Wastewater flowing through sags experiences several changes of slope, and the flow through flat and negative slope sections is prone to a significant reduction in mean velocity. The objective of this study is to determine when pipe sags would result in significant velocities below design conditions, which also would increase the risk of a sewer backup. A sagged pipe configuration that could be encountered in sanitary sewer systems was depicted; thereby, analyses on uniform and gradually varied flows were conducted to determine velocity profiles through different segments of the sagged pipeline setup used for the study. The results indicate that there are significant occurrences when either the velocity in the pipe sags goes below minimum, as recommended in the Ten States Standards (Health Research, Inc., 2004) (0.61 m/s [2.0 ft/ sec]), or flow depth rises to pipe diameter (full section flow). Additionally, velocities along a sagged pipe were calculated for temporal flow rates to account for daily and seasonal flow rate changes in a typical wastewater collection system. Results of the temporal flow rate analysis suggest that, for a 200-mm (8-in.) diameter sagged pipe segment with full-section (wet weather) flow, 75% of the mean velocities would be below the minimum velocity recommended as a Ten States Standard.

  9. Rupture hardware minimization in pressurized water reactor piping

    International Nuclear Information System (INIS)

    Mukherjee, S.K.; Ski, J.J.; Chexal, V.; Norris, D.M.; Goldstein, N.A.; Beaudoin, B.F.; Quinones, D.F.; Server, W.L.

    1989-01-01

    For much of the high-energy piping in light reactor systems, fracture mechanics calculations can be used to assure pipe failure resistance, thus allowing the elimination of excessive rupture restraint hardware both inside and outside containment. These calculations use the concept of leak-before-break (LBB) and include part-through-wall flaw fatigue crack propagation, through-wall flaw detectable leakage, and through-wall flaw stability analyses. Performing these analyses not only reduces initial construction, future maintenance, and radiation exposure costs, but also improves the overall safety and integrity of the plant since much more is known about the piping and its capabilities than would be the case had the analyses not been performed. This paper presents the LBB methodology applied a Beaver Valley Power Station- Unit 2 (BVPS-2); the application for two specific lines, one inside containment (stainless steel) and the other outside containment (ferrutic steel), is shown in a generic sense using a simple parametric matrix. The overall results for BVPS-2 indicate that pipe rupture hardware is not necessary for stainless steel lines inside containment greater than or equal to 6-in. (152-mm) nominal pipe size that have passed a screening criteria designed to eliminate potential problem systems (such as the feedwater system). Similarly, some ferritic steel line as small as 3-in. (76-mm) diameter (outside containment) can qualify for pipe rupture hardware elemination

  10. Pipe rupture hardware minimization in pressurized water reactor system

    International Nuclear Information System (INIS)

    Mukherjee, S.K.; Szyslowski, J.J.; Chexal, V.; Norris, D.M.; Goldstein, N.A.; Beaudoin, B.; Quinones, D.; Server, W.

    1987-01-01

    For much of the high energy piping in light water reactor systems, fracture mechanics calculations can be used to assure pipe failure resistance, thus allowing the elimination of excessive rupture restraint hardware both inside and outside containment. These calculations use the concept of leak-before-break (LBB) and include part-through-wall flaw fatigue crack propagation, through-wall flaw detectable leakage, and through-wall flaw stability analyses. Performing these analyses not only reduces initial construction, future maintenance, and radiation exposure costs, but the overall safety and integrity of the plant are improved since much more is known about the piping and its capabilities than would be the case had the analyses not been performed. This paper presents the LBB methodology applied at Beaver Valley Power Station - Unit 2 (BVPS-2); the application for two specific lines, one inside containment (stainless steel) and the other outside containment (ferritic steel), is shown in a generic sense using a simple parametric matrix. The overall results for BVPS-2 indicate that pipe rupture hardware is not necessary for stainless steel lines inside containment greater than or equal to 6-in (152 mm) nominal pipe size that have passed a screening criteria designed to eliminate potential problem systems (such as the feedwater system). Similarly, some ferritic steel lines as small as 3-in (76 mm) diameter (outside containment) can qualify for pipe rupture hardware elimination

  11. Methodology for Life Testing of Refractory Metal / Sodium Heat Pipes

    International Nuclear Information System (INIS)

    Martin, James J.; Reid, Robert S.

    2006-01-01

    This work establishes an approach to generate carefully controlled data to find heat pipe operating life with material-fluid combinations capable of extended operation. To accomplish this goal acceleration is required to compress 10 years of operational life into 3 years of laboratory testing through a combination of increased temperature and mass fluence. Specific test series have been identified, based on American Society for Testing and Materials (ASTM) specifications, to investigate long-term corrosion rates. The refractory metal selected for demonstration purposes is a molybdenum-44.5% rhenium alloy formed by powder metallurgy. The heat pipes each have an annular crescent wick formed by hot isostatic pressing of molybdenum-rhenium wire mesh. The heat pipes are filled by vacuum distillation with purity sampling of the completed assembly. Round-the-clock heat pipe tests with 6-month destructive and non-destructive inspection intervals are conducted to identify the onset and level of corrosion. Non-contact techniques are employed to provide power to the evaporator (radio frequency induction heating at 1 to 5 kW per heat pipe) and calorimetry at the condenser (static gas gap coupled water cooled calorimeter). The planned operating temperature range extends from 1123 to 1323 K. Accomplishments before project cancellation included successful development of the heat pipe wick fabrication technique, establishment of all engineering designs, baseline operational test requirements, and procurement/assembly of supporting test hardware systems. (authors)

  12. Effect of inlet cone pipe angle in catalytic converter

    Science.gov (United States)

    Amira Zainal, Nurul; Farhain Azmi, Ezzatul; Arifin Samad, Mohd

    2018-03-01

    The catalytic converter shows significant consequence to improve the performance of the vehicle start from it launched into production. Nowadays, the geometric design of the catalytic converter has become critical to avoid the behavior of backpressure in the exhaust system. The backpressure essentially reduced the performance of vehicles and increased the fuel consumption gradually. Consequently, this study aims to design various models of catalytic converter and optimize the volume of fluid flow inside the catalytic converter by changing the inlet cone pipe angles. Three different geometry angles of the inlet cone pipe of the catalytic converter were assessed. The model is simulated in Solidworks software to determine the optimum geometric design of the catalytic converter. The result showed that by decreasing the divergence angle of inlet cone pipe will upsurge the performance of the catalytic converter.

  13. Morbidity profile of steel pipe production workers.

    Science.gov (United States)

    Pandit, Kirti; Tiwari, Rajnarayan R

    2008-08-01

    To study the different morbid conditions among steel pipe producing workers. The present cross-sectional study has been carried out among the workers of one of the steel pipes and tubes manufacturing factory of Gujarat. Hundred workers from the four major departments of the steel pipe production plant, namely welding, pressing machine, X-ray welding and loading/transportation department were covered. The information regarding demographic, occupational, clinical characteristics and diagnosis were recorded on a pre-designed proforma. Statistical analysis included calculation of percentages and proportions and was carried out using the statistical software Epi Info Version 3.3.2. The mean age of the study subjects was found to be 38.7+/-7.1 years. The mean duration of exposure was found to be 9.0+/-3.4 years. Forty-four percent of the subjects had an upper respiratory tract infection, as evidenced by symptoms like dry cough, cough with rhinitis and cough with fever. Symptoms suggestive of allergic bronchitis were observed in 12% of the subjects while symptoms suggestive of heat stress such as prickly heat, dehydration, perspiration and pyrexia were observed in 13% of the subjects.

  14. 33 CFR 157.122 - Piping, valves, and fittings.

    Science.gov (United States)

    2010-07-01

    ... (CONTINUED) POLLUTION RULES FOR THE PROTECTION OF THE MARINE ENVIRONMENT RELATING TO TANK VESSELS CARRYING OIL IN BULK Crude Oil Washing (COW) System on Tank Vessels Design, Equipment, and Installation § 157... system for oil washing and water washing, that piping system must be designed to drain the crude oil into...

  15. 33 CFR 157.222 - Pump and piping arrangements.

    Science.gov (United States)

    2010-07-01

    ... (CONTINUED) POLLUTION RULES FOR THE PROTECTION OF THE MARINE ENVIRONMENT RELATING TO TANK VESSELS CARRYING OIL IN BULK Dedicated Clean Ballast Tanks on Tank Vessels Design and Equipment § 157.222 Pump and... ballast and cargo must be designed to be flushed to the slop tank with water. (c) The piping system of...

  16. Conceptual design of a device for charging PIG's batteries, using the hydraulic energy from the flow in pipe

    Energy Technology Data Exchange (ETDEWEB)

    Ramirez, Ricardo E.; Dutra, Max S. [Alberto Luiz Coimbra Institute for Graduate and Research Studies (COPPE-UFRJ), Rio de Janeiro, RJ (Brazil). Mechanical Engineering Program], e-mail: rramirez@ufrj.br, e-mail: max@mecanica.coppe.ufrj.br

    2009-07-01

    Some actual projects deal with development of PIGs with speed control for liquid pipelines, with the possibility of controlled displacement including counter flow locomotion, in order to inspect and service in 'unpiggable lines' and flexible lines. In this case, it is normal to carry energy consumption greater than the energy disposable in the batteries. This work proposes a device composed by a turbine and an electric generator; presents a preliminary mechanical design of the turbine for the specific requirements of the application like internal pressure inside the line, a range of relative velocities between the PIG and the pipeline and adequate material for the environmental conditions. One of the priority requirements is that the geometric form of the turbine and generator mate with a proposed form of the PIG minimizing the pressure drop in the line for the different work conditions. The electric design defines the magnets characteristics, geometric forms, dimensions and number of turns to obtain the required voltage and power for charging a nominal pack of batteries. (author)

  17. Selection of pipe repair methods.

    Science.gov (United States)

    2013-06-01

    The objective of this research is to provide pipeline operators with testing procedures and : results of the performance of composite pipe repair methods and ultimately, improve their : selection and installation, and reduce the risks associated with...

  18. Light pipes for LED measurements

    Science.gov (United States)

    Floyd, S. R.; Thomas, E. F., Jr.

    1976-01-01

    Light pipe directly couples LED optical output to single detector. Small area detector measures total optical output of diode. Technique eliminates thermal measurement problems and channels optical output to remote detector.

  19. Pulsating Heat Pipes, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Large radiator panels, based upon state of the art conventional heat pipes with attached fins for thermal load distribution and dissipation is the current baseline...

  20. Characterization of Accelerating Pipe Flow.

    Science.gov (United States)

    1988-03-01

    Journal of Chemical Engineering of Japan , vol...92, January 1970. 17. K. Kataoka, T. Kawabata, and K. Miki, "The Start-Up Response of Pipe Flow to a Step Change in Flow Rate," Journal of Chemical Engineering of Japan , vol...Pipe Flows," Journal of Chemical Engineering of Japan , vol. 9, no. 6, pp. 431-439, 1975. 19. E. van de Sande, A.P. Belde, B.J.G. Hamer, and W.

  1. High temperature failure of long-seam welded low chrome piping in catalytic reforming service

    Energy Technology Data Exchange (ETDEWEB)

    Dobis, J.D. [BP Oil Co., Marcus Hook, PA (United States). Marcus Hook Refinery; Brown, R.G.; Osage, D.A.; Buchheim, G.M. [BP Oil Co., Cleveland, OH (United States). Engineering Services Dept.

    1995-12-01

    A section of NPS 36 inch diameter 1-1/4Cr-1/2Mo inlet piping to a continuously regenerating catalytic reforming reactor split open at the long-seam weld after 100,000 hours service. The results of metallurgical analysis confirmed failure by creep crack growth initiating at the ID, yet accelerated creep tests using the Omega method showed that the failed piping exhibited excellent creep strength and creep ductility in both base and weld metals. In addition, a piping stress analysis demonstrated that the piping design was in compliance with the ASME B31.3 Piping Code. Detailed finite element analysis revealed that the failure was promoted by peaking of the long-seam weld which caused highly localized bending stresses that are only partially relaxed after long term high temperature exposure. The peaked geometry satisfies existing fabrication tolerances for commonly used long-seam welded refinery piping including the ASTM A691 specification.

  2. Response of HDR-VKL piping system to seismic test excitations

    International Nuclear Information System (INIS)

    Srinivasan, M.G.; Kot, C.A.; Hsieh, B.J.

    1989-01-01

    As part of the earthquake investigations at the HDR (Heissdampfreaktor) test facility in Kahl/Main, FRG, simulated seismic tests (SHAM) were performed during April-May 1988 on the VKL (Versuchskreislauf) piping system. The purpose of the SHAM tests was to study the behavior of piping subjected to a range of seismic excitation levels including those that exceed design levels many times and might induce failure of pipe supports of plasticity in the pipe runs, and to establish seismic margins for piping and pipe supports. Data obtained in the tests are also used to validate analysis methods. The objective of the work reported is to evaluate a subsystem analysis module of the SMACS code. This module is a linear, finite-element-based program capable of calculating the response of nuclear power plant subsystems subjected to independent multiple- acceleration input excitation. The evaluation is based on a comparison of computational results of simulated SHAM tests with corresponding test measurements

  3. Vibration Control of Nuclear Power Plant Piping System Using Stockbridge Damper under Earthquakes

    Directory of Open Access Journals (Sweden)

    Seongkyu Chang

    2016-01-01

    Full Text Available Generally the piping system of a nuclear power plant (NPP has to be designed for normal loads such as dead weight, internal pressure, temperature, and accidental loads such as earthquake. In the proposed paper, effect of Stockbridge damper to mitigate the response of piping system of NPP subjected to earthquake is studied. Finite element analysis of piping system with and without Stockbridge damper using commercial software SAP2000 is performed. Vertical and horizontal components of earthquakes such as El Centro, California, and Northridge are used in the piping analysis. A sine sweep wave is also used to investigate the control effects on the piping system under wide frequency range. It is found that the proposed Stockbridge damper can reduce the seismic response of piping system subjected to earthquake loading.

  4. Specialist meeting on leak before break in reactor piping and vessels

    International Nuclear Information System (INIS)

    Bartholome, G.; Bazant, E.; Wellein, R.

    1997-01-01

    A series of research projects sponsored by the Federal Minister for Education, Science, Research and Technology, Bonn are summarized and compared to utility, manufacturer, and vendor tests. The purpose of the evaluation was to experimentally verify Leak-before-Break behavior, confirm the postulation of fracture preclusion for piping (straight pipe, bends and branches), and quantify the safety margin against massive failure. The results are applicable to safety assessment of ferritic and austenitic piping in primary and secondary nuclear power plant circuits. Moreover, because of the wide range of the test parameters, they are also important for the design and assessment of piping in other technical plant. The test results provide justification for ruling out catastrophic fractures, even on pipes of dimensions corresponding to those of a main coolant pipe of a pressurized water reactor plant on the basis of a mechanical deterministic safety analysis in correspondence with the Basis Safety Concept (Principle of Fracture Exclusion)

  5. Evaluation of the plastic characteristics of piping products in relation to ASME code criteria

    International Nuclear Information System (INIS)

    Rodabaugh, E.C.; Moore, S.E.

    1978-07-01

    Theories and test data relevant to the plastic characteristics of piping products are presented and compared with Code Equations in NB-3652 for Class 1 piping; in NC/ND-3652.2 for Class 2 and Class 3 piping. Comparisons are made for (a) straight pipe, (b) elbows, (c) branch connections, and (d) tees. The status of data (or lack of data) for other piping components is discussed. Comparisons are made between available data and the Code equations for two typical piping materials, SA106 Grade B and SA312 TP304, for Code Design Limits, and Service Limits A, B, C, and D. Conditions under which the Code Limits cannot be shown to be conservative from available data are pointed out. Based on the results of the study, recommendations for Code revisions are presented, along with recommendations for additional work

  6. Stress analysis of the O-element pipe during the process of flue gases purification

    Directory of Open Access Journals (Sweden)

    Nekvasil R.

    2008-11-01

    Full Text Available Equipment for flue gases purification from undesired substances is used throughout power and other types of industry. This paper deals with damaging of the O-element pipe designed to remove sulphur from the flue gases, i.e. damaging of the pipe during flue gases purification. This purification is conducted by spraying the water into the O-shaped pipe where the flue gases flow. Thus the sulphur binds itself onto the water and gets removed from the flue gas. Injection of cold water into hot flue gases, however, causes high stress on the inside of the pipe, which can gradually damage the O-element pipe. In this paper initial injection of water into hot pipe all the way to stabilization of temperature fields will be analyzed and the most dangerous places which shall be considered for fatigue will be determined.

  7. A Lift-Off-Tolerant Magnetic Flux Leakage Testing Method for Drill Pipes at Wellhead.

    Science.gov (United States)

    Wu, Jianbo; Fang, Hui; Li, Long; Wang, Jie; Huang, Xiaoming; Kang, Yihua; Sun, Yanhua; Tang, Chaoqing

    2017-01-21

    To meet the great needs for MFL (magnetic flux leakage) inspection of drill pipes at wellheads, a lift-off-tolerant MFL testing method is proposed and investigated in this paper. Firstly, a Helmholtz coil magnetization method and the whole MFL testing scheme are proposed. Then, based on the magnetic field focusing effect of ferrite cores, a lift-off-tolerant MFL sensor is developed and tested. It shows high sensitivity at a lift-off distance of 5.0 mm. Further, the follow-up high repeatability MFL probing system is designed and manufactured, which was embedded with the developed sensors. It can track the swing movement of drill pipes and allow the pipe ends to pass smoothly. Finally, the developed system is employed in a drilling field for drill pipe inspection. Test results show that the proposed method can fulfill the requirements for drill pipe inspection at wellheads, which is of great importance in drill pipe safety.

  8. A Lift-Off-Tolerant Magnetic Flux Leakage Testing Method for Drill Pipes at Wellhead

    Directory of Open Access Journals (Sweden)

    Jianbo Wu

    2017-01-01

    Full Text Available To meet the great needs for MFL (magnetic flux leakage inspection of drill pipes at wellheads, a lift-off-tolerant MFL testing method is proposed and investigated in this paper. Firstly, a Helmholtz coil magnetization method and the whole MFL testing scheme are proposed. Then, based on the magnetic field focusing effect of ferrite cores, a lift-off-tolerant MFL sensor is developed and tested. It shows high sensitivity at a lift-off distance of 5.0 mm. Further, the follow-up high repeatability MFL probing system is designed and manufactured, which was embedded with the developed sensors. It can track the swing movement of drill pipes and allow the pipe ends to pass smoothly. Finally, the developed system is employed in a drilling field for drill pipe inspection. Test results show that the proposed method can fulfill the requirements for drill pipe inspection at wellheads, which is of great importance in drill pipe safety.

  9. Specialist meeting on leak before break in reactor piping and vessels

    Energy Technology Data Exchange (ETDEWEB)

    Bartholome, G.; Bazant, E.; Wellein, R. [Siemens KWU, Stuttgart (Germany)] [and others

    1997-04-01

    A series of research projects sponsored by the Federal Minister for Education, Science, Research and Technology, Bonn are summarized and compared to utility, manufacturer, and vendor tests. The purpose of the evaluation was to experimentally verify Leak-before-Break behavior, confirm the postulation of fracture preclusion for piping (straight pipe, bends and branches), and quantify the safety margin against massive failure. The results are applicable to safety assessment of ferritic and austenitic piping in primary and secondary nuclear power plant circuits. Moreover, because of the wide range of the test parameters, they are also important for the design and assessment of piping in other technical plant. The test results provide justification for ruling out catastrophic fractures, even on pipes of dimensions corresponding to those of a main coolant pipe of a pressurized water reactor plant on the basis of a mechanical deterministic safety analysis in correspondence with the Basis Safety Concept (Principle of Fracture Exclusion).

  10. Modeling of heat transfer into a heat pipe for a localized heat input zone

    International Nuclear Information System (INIS)

    Rosenfeld, J.H.

    1987-01-01

    A general model is presented for heat transfer into a heat pipe using a localized heat input. Conduction in the wall of the heat pipe and boiling in the interior structure are treated simultaneously. The model is derived from circumferential heat transfer in a cylindrical heat pipe evaporator and for radial heat transfer in a circular disk with boiling from the interior surface. A comparison is made with data for a localized heat input zone. Agreement between the theory and the model is good. This model can be used for design purposes if a boiling correlation is available. The model can be extended to provide improved predictions of heat pipe performance

  11. Survey of strong motion earthquake effects on thermal power plants in California with emphasis on piping systems. Volume 2, Appendices

    Energy Technology Data Exchange (ETDEWEB)

    Stevenson, J.D. [Stevenson and Associates, Cleveland, OH (United States)

    1995-11-01

    Volume 2 of the ``Survey of Strong Motion Earthquake Effects on Thermal Power Plants in California with Emphasis on Piping Systems`` contains Appendices which detail the detail design and seismic response of several power plants subjected to strong motion earthquakes. The particular plants considered include the Ormond Beach, Long Beach and Seal Beach, Burbank, El Centro, Glendale, Humboldt Bay, Kem Valley, Pasadena and Valley power plants. Included is a typical power plant piping specification and photographs of typical power plant piping specification and photographs of typical piping and support installations for the plants surveyed. Detailed piping support spacing data are also included.

  12. Development of Intelligent pipe Locator

    Energy Technology Data Exchange (ETDEWEB)

    Miyamoto, Yukinori

    1987-09-10

    As the cities gets denser, development of a pipe locator, which can easily detect the position of the complicatedly buried underground pipes with high accuracy, is greatly demanded. A newly developed intelligent pipe locator detects a magnetic field generated by flowing an alternating-current through a buried pipe by means of a sensor unit placed on the ground and by computing and displaying with a micro-computer the position, depth, and the reliability of the detected result in only 3 seconds. Results of a half year field test since Sept. 1986 shows that the error was improved twice up to 5% from 10% of the conventional pipe locator. Operation time was also reduced down to one-fifth of the former method. By the practical use of this locator on the spot, one can expect the security improvements, reduction of frilling cost, and more efficient operation. In Japan recently, the number of conventional pipe locator is more than 5000 units in about 15 types. (10 figs, 7 tabs)

  13. Heat transfer characteristics and limitations analysis of heat-pipe-cooled thermal protection structure

    International Nuclear Information System (INIS)

    Guangming, Xiao; Yanxia, Du; Yewei, Gui; Lei, Liu; Xiaofeng, Yang; Dong, Wei

    2014-01-01

    The theories of heat transfer, thermodynamics and fluid dynamics are employed to develop the coupled heat transfer analytical methods for the heat-pipe-cooled thermal protection structure (HPC TPS), and a three-dimensional numerical method considering the sonic limit of heat pipe is proposed. To verify the calculation correctness, computations are carried out for a typical heat pipe and the results agree well with experimental data. Then, the heat transfer characteristics and limitations of HPC TPS are mainly studied. The studies indicate that the use of heat pipe can reduce the temperature at high heat flux region of structure efficiently. However, there is a frozen startup period before the heat pipe reaching a steady operating state, and the sonic limit will be a restriction on the heat transfer capability. Thus, the effects of frozen startup must be considered for the design of HPC TPS. The simulation model and numerical method proposed in this paper can predict the heat transfer characteristics of HPC TPS quickly and exactly, and the results will provide important references for the design or performance evaluation of HPC TPS. - Highlights: • Numerical methods for the heat-pipe-cooled thermal protection structure are studied. • Three-dimensional simulation model considering sonic limit of heat pipe is proposed. • The frozen startup process of the embedded heat pipe can be predicted exactly. • Heat transfer characteristics of TPS and limitations of heat pipe are discussed

  14. Piping hydrodynamic loads for a PWR power up-rate with steam generator replacement

    International Nuclear Information System (INIS)

    Julie M Jarvis; Allen T Vieira; James M Gilmer

    2005-01-01

    Full text of publication follows: Pipe break hydrodynamic loads are calculated for various systems in a PWR for a Power Up-rate (PUR) with a Steam Generator Replacement (SGR). PUR with SGR can change the system pressures, mass flowrates and pipe routing/configuration. These changes can alter the steam generator piping steam/water hammer loads. This paper discusses the need to benchmark against the original design basis, the use of different modeling techniques, and lessons learned. Benchmarking for licensing in the United States is vital in consideration of 10CFR50.59 and other licensing and safety issues. RELAP5 and its force post-processor R5FORCE are used to model the transient loads for various piping systems such as main feedwater and blowdown systems. Other modeling applications, including the Bechtel GAFT program, are used to evaluate loadings in the main steam piping. Forces are calculated for main steam turbine stop valve closure, feedwater pipe breaks and subsequent check valve slam, and blowdown isolation valve closure. These PUR/SGR forces are compared with the original design basis forces. Modeling techniques discussed include proper valve closure modeling, sonic velocity changes due to pipe material changes, and two phase flow effects. Lessons learned based on analyses done for several PWR PUR with SGR are presented. Lessons learned from these analyses include choosing the optimal replacement piping size and routing to improve system performance without resulting in excessive piping loads. (authors)

  15. Leaks in pipe networks

    Science.gov (United States)

    Pudar, Ranko S.; Liggett, James A.

    1992-01-01

    Leak detection in water-distribution systems can be accomplished by solving an inverse problem using measurements of pressure and/or flow. The problem is formulated with equivalent orifice areas of possible leaks as the unknowns. Minimization of the difference between measured and calculated heads produces a solution for the areas. The quality of the result depends on number and location of the measurements. A sensitivity matrix is key to deciding where to make measurements. Both location and magnitude of leaks are sensitive to the quantity and quality of pressure measurements and to how well the pipe friction parameters are known. The overdetermined problem (more measurements than suspected leaks) gives the best results, but some information can be derived from the underdetermined problem. The variance of leak areas, based on the quality of system characteristics and pressure data, indicates the likely accuracy of the results. The method will not substitute for more traditional leak surveys but can serve as a guide and supplement.

  16. Piping inspection round robin

    International Nuclear Information System (INIS)

    Heasler, P.G.; Doctor, S.R.

    1996-04-01

    The piping inspection round robin was conducted in 1981 at the Pacific Northwest National Laboratory (PNNL) to quantify the capability of ultrasonics for inservice inspection and to address some aspects of reliability for this type of nondestructive evaluation (NDE). The round robin measured the crack detection capabilities of seven field inspection teams who employed procedures that met or exceeded the 1977 edition through the 1978 addenda of the American Society of Mechanical Engineers (ASME) Section 11 Code requirements. Three different types of materials were employed in the study (cast stainless steel, clad ferritic, and wrought stainless steel), and two different types of flaws were implanted into the specimens (intergranular stress corrosion cracks (IGSCCs) and thermal fatigue cracks (TFCs)). When considering near-side inspection, far-side inspection, and false call rate, the overall performance was found to be best in clad ferritic, less effective in wrought stainless steel and the worst in cast stainless steel. Depth sizing performance showed little correlation with the true crack depths

  17. Experimental study of Large-scale cryogenic Pulsating Heat Pipe

    Science.gov (United States)

    Barba, Maria; Bruce, Romain; Bonelli, Antoine; Baudouy, Bertrand

    2017-12-01

    Pulsating Heat Pipes (PHP) are passive two-phase heat transfer devices consisting of a long capillary tube bent into many U-turns connecting the condenser part to the evaporator part. They are thermally driven by an oscillatory flow of liquid slugs and vapor plugs coming from phase changes and pressure differences along the tube. The coupling of hydrodynamic and thermodynamic effects allows high heat transfer performances. Three closed-loop pulsating heat pipes have been developed by the DACM (Department of Accelerators, Cryogenics and Magnetism) of CEA Paris-Saclay, France. Each PHP measures 3.7 meters long (0.35 m for the condenser and the evaporator and 3 m for the adiabatic part), being almost 20 times longer than the longest cryogenic PHP tested. These PHPs have 36, 22 and 12 parallel channels. Numerous tests have been performed in horizontal position (the closest configuration to non-gravity) using nitrogen as working fluid, operating between 75 and 90 K. The inner and outer diameters of the stainless steel capillary tubes are 1.5 and 2 mm respectively. The PHPs were operated at different filling ratios (20 to 90 %), heat input powers (3 to 20 W) and evaporator and condenser temperatures (75 to 90 K). As a result, the PHP with 36 parallel channels achieves a certain level of stability during more than thirty minutes with an effective thermal conductivity up to 200 kW/m.K at 10 W heat load and during forty minutes with an effective thermal conductivity close to 300 kW/m.K at 5 W heat load.

  18. Optimization and Annual Average Power Predictions of a Backward Bent Duct Buoy Oscillating Water Column Device Using the Wells Turbine.

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Christopher S. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Bull, Diana L [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Willits, Steven M. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Fontaine, Arnold A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2014-08-01

    This Technical Report presents work completed by The Applied Research Laboratory at The Pennsylvania State University, in conjunction with Sandia National Labs, on the optimization of the power conversion chain (PCC) design to maximize the Average Annual Electric Power (AAEP) output of an Oscillating Water Column (OWC) device. The design consists of two independent stages. First, the design of a floating OWC, a Backward Bent Duct Buoy (BBDB), and second the design of the PCC. The pneumatic power output of the BBDB in random waves is optimized through the use of a hydrodynamically coupled, linear, frequency-domain, performance model that links the oscillating structure to internal air-pressure fluctuations. The PCC optimization is centered on the selection and sizing of a Wells Turbine and electric power generation equipment. The optimization of the PCC involves the following variables: the type of Wells Turbine (fixed or variable pitched, with and without guide vanes), the radius of the turbine, the optimal vent pressure, the sizing of the power electronics, and number of turbines. Also included in this Technical Report are further details on how rotor thrust and torque are estimated, along with further details on the type of variable frequency drive selected.

  19. Heat-pipe development for the SPAR space-power system

    International Nuclear Information System (INIS)

    Ranken, W.A.

    1981-01-01

    The SPAR space power system design is based on a high temperature fast spectrum nuclear reactor that furnishes heat to a thermoelectric conversion system to generate an electrical power output of 100 kW/sub (e)/. An important feature of this design is the use of alkali metal heat pipes to provide redundant, reliable, and low-loss heat transfer at high temperature. Three sets of heat pipes are used in the system. These include sodium/molybdenum heat pipes to transfer heat from the reactor core to the conversion system, potassium/niobium heat pipes to couple the conversion system to the radiator in a redundant manner, and potassium/titanium heat pipes to distribute rejected heat throughout the radiator surface. The designs of these units are discussed and fabrication methods and testing results are described. 12 figures

  20. Heat pipes. (Latest citations from the US Patent Bibliographic file with exemplary claims). Published Search

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-01-01

    The bibliography contains citations of selected patents concerning the design, manufacture, and applications of heat pipes. The use of heat pipes in heat exchange systems for heat storage, heat transfer, and heat utilization is discussed. Applications include semiconductor cooling, use in engine components, and building cooling and heating. (Contains 250 citations and includes a subject term index and title list.)

  1. An intelligent scheduling method based on improved particle swarm optimization algorithm for drainage pipe network

    Science.gov (United States)

    Luo, Yaqi; Zeng, Bi

    2017-08-01

    This paper researches the drainage routing problem in drainage pipe network, and propose an intelligent scheduling method. The method relates to the design of improved particle swarm optimization algorithm, the establishment of the corresponding model from the pipe network, and the process by using the algorithm based on improved particle swarm optimization to find the optimum drainage route in the current environment.

  2. Evaluation of 3 Inch SN-219 Failure and S and SX Tank Farm Saltwell Piping

    International Nuclear Information System (INIS)

    ELSEN, J.J.

    2000-01-01

    Evaluation of direct buried piping currently in use or designated for future Saltwell pumping in S and SX Farms. Documented evaluation of failed S-103 saltwell pumping transfer line 3 inch SN-219. This evaluation is intended to reflect current status of Saltwell piping, when taken in context with referenced documents

  3. 46 CFR 52.01-105 - Piping, valves and fittings (modifies PG-58 and PG-59).

    Science.gov (United States)

    2010-10-01

    ... other suitable means employed to reduce the effects of metal temperature differentials. (e) Blowoff...-59). (a) Boiler external piping within the jurisdiction of the ASME Boiler and Pressure Vessel Code... and Pressure Vessel Code, boiler external piping must: (1) Meet the design conditions and criteria in...

  4. Effect of cross section on collapse load in pipe bends subjected to in ...

    African Journals Online (AJOL)

    user

    Therefore, a closed-form solution is proposed to determine collapse load of pipe bend based on the finite element results of elliptic cross ..... T.Christo Michael received the ME in Computer Aided Design from B.S.A.R. Crescent Engineering College, Anna University in 2008, and pursuing PhD in the area of analysis in pipe ...

  5. The Geometry Optimisation of a Triple Branch Pipe Using Finite Element Method

    OpenAIRE

    Dorian Nedelcu; Vasile Cojocaru; Călin-Octavian Miclosină

    2008-01-01

    The paper presents the geometrical optimization of a triple branch pipesubmitted to an internal pressure. The goal of the optimization was todetermine the optimum thickness of piping and branch pipe ribs, in thecondition of reaching admissible values of the stress and displacement.The resistance calculus was realized with Cosmos DesignStar softwareand the geometry was modeled with Microstation Modeler software.

  6. 46 CFR 154.506 - Mechanical expansion joint: Limits in a piping system.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Mechanical expansion joint: Limits in a piping system... DANGEROUS CARGOES SAFETY STANDARDS FOR SELF-PROPELLED VESSELS CARRYING BULK LIQUEFIED GASES Design, Construction and Equipment Cargo and Process Piping Systems § 154.506 Mechanical expansion joint: Limits in a...

  7. Hydrogen permeation resistant heat pipe for bi-modal reactors. Final report, October 1, 1994--September 30, 1995

    International Nuclear Information System (INIS)

    North, M.T.; Anderson, W.G.

    1995-01-01

    The principal objective of this program was to demonstrate technology that will make a sodium heat pipe tolerant of hydrogen permeation for a bimodal space reactor application. Special focus was placed on techniques which enhance the permeation of hydrogen out of the heat pipe. Specific objectives include: define the detailed requirements for the bimodal reactor application; design and fabricate a prototype heat pipe tolerant of hydrogen permeation; and test the prototype heat pipe and demonstrate that hydrogen which permeates into the heat pipe is removed or reduced to acceptable levels. The results of the program were fully successful. Analyses were performed on two different heat pipe designs and an experimental heat pipe was fabricated and tested. A model of the experimental heat pipe was developed to predict the enhancement in the hydrogen permeation rate out of the heat pipe. A significant improvement in the rate at which hydrogen permeates out of a heat pipe was predicted for the use of the special condenser geometry developed here. Agreement between the model and the experimental results was qualitatively good. Inclusion of the additional effects of fluid flow in the heat pipe are recommended for future work

  8. Seismic fragility test of a 6-inch diameter pipe system

    International Nuclear Information System (INIS)

    Chen, W.P.; Onesto, A.T.; DeVita, V.

    1987-02-01

    This report contains the test results and assessments of seismic fragility tests performed on a 6-inch diameter piping system. The test was funded by the US Nuclear Regulatory Commission (NRC) and conducted by ETEC. The objective of the test was to investigate the ability of a representative nuclear piping system to withstand high level dynamic seismic and other loadings. Levels of loadings achieved during seismic testing were 20 to 30 times larger than normal elastic design evaluations to ASME Level D limits would permit. Based on failure data obtained during seismic and other dynamic testing, it was concluded that nuclear piping systems are inherently able to withstand much larger dynamic seismic loadings than permitted by current design practice criteria or predicted by the probabilistic risk assessment (PRA) methods and several proposed nonlinear methods of failure analysis

  9. Specifying and manufacturing piping for the fast flux test facility

    International Nuclear Information System (INIS)

    Moen, R.A.; O'Keefe, D.P.; Irvin, J.E.; Tobin, J.C.

    1974-01-01

    Specification of materials for liquid metal reactor coolant piping, at service temperatures up to 1200 0 F, involves a number of considerations unique to these systems. The mechanical property/design allowable stress considerations which led to the selection and specification of specific materials for the Fast Flux Test Facility piping are discussed. Additional considerations are described indicating allowances made for material changes anticipated in service. These measures primarily involved raising the minimum carbon content to a value that would insure the strength of the material always remains above that assumed in the initial design, although other considerations are discussed. The processes by which this piping was manufactured, its resulting characteristics and methods of subsequent handling/assembly are briefly discussed. (U.S.)

  10. An acoustic technique for tracing plastic pipe

    Energy Technology Data Exchange (ETDEWEB)

    Huebler, J.E.; Campbell, B.K. (Inst. of Gas Technology, Chicago, IL (United States)); Ching, G.K. (Southern California Gas Co., Los Angeles, CA (United States). Research Dept.)

    1993-08-01

    Many operation and maintenance activities performed by a gas distribution company require precise knowledge of the location of the gas main and/or service. These activities range from pipe location for the repair of a leak to the marking of pipe location as part of a one call system. Records provide one method of knowing the location of piping; however, these records are not always sufficiently accurate for field work. Thus, techniques for pipe location have always been an important need of the industry, and electromagnetic pipe locators have filled this need for years. Electromagnetic pipe locators, however, cannot find plastic pipe unless a tracer wire is buried next to or above the pipe. With the increased use of plastic pipe, a new technique for finding buried pipe is required. A successful acoustic plastic pipe locator could eliminate the use of tracer wire in new polyethylene pipe installations, thereby reducing pipe installation costs. Under sponsorship of the Southern California Gas Company, the Institute of Gas Technology (IGT) successfully demonstrated the proof-of-concept of an active acoustic plastic pipe location technique and is developing the technique into a practical field instrument.

  11. Seismic ratchet-fatigue failure of piping systems

    International Nuclear Information System (INIS)

    Severud, L.K.; Anderson, M.J.; Lindquist, M.R.; Weiner, E.O.

    1986-01-01

    Failures of piping systems during earthquakes have been rare. Those that have failed were either made of brittle material such as cast iron, were rigid systems between major components where component relative seismic motions tore the pipe out of the component, or were high pressure systems where a ratchet-fatigue fracture followed a local bulging of the pipe diameter. Tests to failure of an unpressurized 3-in. and a pressurized 6-in. diameter carbon steel nuclear pipe systems subjected to high level shaking have been accomplished. Failure analyses of these tests are presented and correlated to the test results. It was found that failure of the unpressurized system could be correlated well with standard ASME type fatigue analysis predictions. Moreover, the pressurized system failure occurred in significantly less load cycles than predicted by standard fatigue analysis. However, a ratchet-fatigue and ductility exhaustion analysis of the pressurized system did correlate very well. These findings indicate modifications to design analysis methods and the present ASME Code piping design rules may be appropriate to cover the ratchet-fatigue failure mode

  12. Crack stability analysis of low alloy steel primary coolant pipe

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, T.; Kameyama, M. [Kansai Electric Power Company, Osaka (Japan); Urabe, Y. [Mitsubishi Heavy Industries, Ltd., Takasago (Japan)] [and others

    1997-04-01

    At present, cast duplex stainless steel has been used for the primary coolant piping of PWRs in Japan and joints of dissimilar material have been applied for welding to reactor vessels and steam generators. For the primary coolant piping of the next APWR plants, application of low alloy steel that results in designing main loops with the same material is being studied. It means that there is no need to weld low alloy steel with stainless steel and that makes it possible to reduce the welding length. Attenuation of Ultra Sonic Wave Intensity is lower for low alloy steel than for stainless steel and they have advantageous inspection characteristics. In addition to that, the thermal expansion rate is smaller for low alloy steel than for stainless steel. In consideration of the above features of low alloy steel, the overall reliability of primary coolant piping is expected to be improved. Therefore, for the evaluation of crack stability of low alloy steel piping to be applied for primary loops, elastic-plastic future mechanics analysis was performed by means of a three-dimensioned FEM. The evaluation results for the low alloy steel pipings show that cracks will not grow into unstable fractures under maximum design load conditions, even when such a circumferential crack is assumed to be 6 times the size of the wall thickness.

  13. Critical element development of standard pipe connector for remote handling

    International Nuclear Information System (INIS)

    Taguchi, Kou; Kakudate, Satoshi; Kanamori, Naokazu; Oka, Kiyoshi; Nakahira, Masataka; Obara, Kenjiro; Tada, Eisuke; Shibanuma, Kiyoshi; Seki, Masahiro

    1994-08-01

    In fusion experimental reactors such as ITER, the in-vessel components such as blanket and divertor are actively cooled and a large number of cooling pipes are located around the core of reactor, where personnel access is prohibited. Mechanical pipe connectors are highly required as standard components for easy and reliable connection/disconnection of cooling pipe by remote handling. For this purpose, a clamping chain type connector has been developed with special mechanisms such as plate springs and guide structures so as to enable concentric and axial movement of clamping chain for easy mounting and dismounting. The basic performance test of a prototypical connector for a 80-A pipe shows sufficient leak tightness and proof pressure capability as well as simple connection/disconnection operation. In addition to the clamp chain type connector, design efforts have been made to develop a quick coupling type connector and a preliminary model of air-actuated quick connector has been fabricated for further investigations. This paper gives the design concept of mechanical pipe connectors such as clamping chain type and quick coupler type, and the basic performance tests results of clamping chain type connector. (author)

  14. Dictionary of pressure vessel and piping technology

    International Nuclear Information System (INIS)

    Jentgen, L.; Schmitz, H.P.

    1986-01-01

    A specialised dictionary has been compiled containing the appropriate English and German terms in the following technical fields: materials science, welding, destructive and non-destructive testing, thermal and mass transfer, the design and construction in particular of pressure vessels, tanks, heat exchangers, piping, expansion joints, valves, and components associated with the above fields. This dictionary is the result of many years spent in evaluating technical terminology from the relevant American and British regulations, technical rules, standards, and specifications (see bibliography) and correlating these with the terminology of comparable German regulations, rules and standards, together with the essential technical literature. (orig.) [de

  15. SEALING LARGE-DIAMETER CAST-IRON PIPE JOINTS UNDER LIVE CONDITIONS

    Energy Technology Data Exchange (ETDEWEB)

    Kiran M Kothari; Gerard T. Pittard

    2004-07-01

    Utilities in the U.S. operate over 75,000 km (47,000 miles) of old cast-iron pipes for gas distribution. The bell-and-spigot joints that connect pipe sections together tend to leak as these pipes age. Current repair practices are costly and highly disruptive. The objective of this program is to design, test and commercialize a robotic system capable of sealing multiple castiron bell and spigot joints from a single pipe entry point. The proposed system will perform repairs while the pipe remains in service by traveling through the pipe, cleaning each joint surface, and installing a stainless-steel sleeve lined with an epoxy-impregnated felt across the joint. This approach will save considerable time and labor, avoid traffic disruption, and eliminate any requirement to interrupt service to customers (which would result in enormous expense to utilities). Technical challenges include: (1) repair sleeves must compensate for diametric variation and eccentricity of cast-iron pipes; (2) the assembly must travel long distances through pipes containing debris; (3) the pipe wall must be effectively cleaned in the immediate area of the joint to assure good bonding of the sleeve; and (4) an innovative bolt-on entry fitting is required to conduct repair operations on live mains. The development effort is divided into eleven tasks. Task 1 (Program Management) and Task 2 (Establishment of Detailed Design Specifications) were completed in prior quarters while Task 3 (Design and Fabricate Ratcheting Stainless-Steel Repair Sleeves) has progressed to installing prototype sleeves in cast iron test pipe segments. Efforts in this quarter continued to focus on Tasks 4-8, with significant progress made in each. Task 4 (Design, Fabricate and Test Patch Setting Robotic Train) progressed to the design of the control electronics and pneumatic system to inflate the bladder robotic patch setting module. Task 5 (Design & Fabricate Pipe-Wall Cleaning Robot Train with Pan/Zoom/Tilt Camera

  16. Felt-metal-wick heat-pipe solar receiver

    Energy Technology Data Exchange (ETDEWEB)

    Andraka, C.E.; Adkins, D.R.; Moss, T.A. [Sandia National Labs., Albuquerque, NM (United States); Cole, H.M. [Porous Metal Products, Jacksboro, TX (United States); Andreas, N.H. [Bekaert Corp., Marietta, GA (United States)

    1994-12-31

    Reflux heat-pipe receivers have been identified as a desirable interface to couple a Stirling-cycle engine with a parabolic dish solar concentrator. The reflux receiver provides power nearly isothermally to the engine heater heads while decoupling the heater head design from the solar absorber surface design. The independent design of the receiver and engine heater head leads to higher system efficiency. Heat pipe reflux receivers have been demonstrated at approximately 65 kW{sub t} power throughput. Several 25 to 30-kW{sub e} Stirling-cycle engines are under development, and will soon be incorporated in commercial dish-Stirling systems. These engines will require reflux receivers with power throughput limits reaching 90-kW{sub t}. The extension of heat pipe technology from 60 kW{sub t} to 100 kW{sub t} is not trivial. Current heat pipe wick technology is pushed to its limits. It is necessary to develop and test advanced wick structure technologies to perform this task. Sandia has developed and begun testing a Bekaert Corporation felt metal wick structure fabricated by Porous Metal Products Inc. This wick is about 95% porous, and has liquid permeability a factor of 2 to 8 times higher than conventional technologies for a given maximum pore radius. The wick has been successfully demonstrated in a bench-scale heat pipe, and a full-scale on-sun receiver has been fabricated. This report details the wick design, characterization and installation into a heat pipe receiver, and the results of the bench-scale tests are presented. The wick performance is modeled, and the model results are compared to test results.

  17. A quantitative evaluation of seismic margin of typical sodium piping

    International Nuclear Information System (INIS)

    Morishita, Masaki

    1999-05-01

    It is widely recognized that the current seismic design methods for piping involve a large amount of safety margin. From this viewpoint, a series of seismic analyses and evaluations with various design codes were made on typical LMFBR main sodium piping systems. Actual capability against seismic loads were also estimated on the piping systems. Margins contained in the current codes were quantified based on these results, and potential benefits and impacts to the piping seismic design were assessed on possible mitigation of the current code allowables. From the study, the following points were clarified; 1) A combination of inelastic time history analysis and true (without margin)strength capability allows several to twenty times as large seismic load compared with the allowable load with the current methods. 2) The new rule of the ASME is relatively compatible with the results of inelastic analysis evaluation. Hence, this new rule might be a goal for the mitigation of seismic design rule. 3) With this mitigation, seismic design accommodation such as equipping with a large number of seismic supports may become unnecessary. (author)

  18. Flexible ultrasonic pipe inspection apparatus

    Science.gov (United States)

    Jenkins, C.F.; Howard, B.D.

    1998-06-23

    A flexible, modular ultrasonic pipe inspection apparatus, comprises a flexible, hollow shaft that carries a plurality of modules, including at least one rotatable ultrasonic transducer, a motor/gear unit, and a position/signal encoder. The modules are connected by flexible knuckle joints that allow each module of the apparatus to change its relative orientation with respect to a neighboring module, while the shaft protects electrical wiring from kinking or buckling while the apparatus moves around a tight corner. The apparatus is moved through a pipe by any suitable means, including a tether or drawstring attached to the nose or tail, differential hydraulic pressure, or a pipe pig. The rotational speed of the ultrasonic transducer and the forward velocity of the apparatus are coordinated so that the beam sweeps out the entire interior surface of the pipe, enabling the operator to accurately assess the condition of the pipe wall and determine whether or not leak-prone corrosion damage is present. 7 figs.

  19. Flow induced vibrations of piping

    International Nuclear Information System (INIS)

    Gibert, R.J.; Axisa, F.

    1977-01-01

    This paper presents a method to take into account the inertial effects and the fluid compressibility by solving a coupled mechanical-acoustical problem: the computer code TEDEL of the C.E.A./D.E.M.T. System, based on the finite-element method, has been extended to calculate simultaneously the pressure fluctuations in the fluid and the vibrations of the pipe. By this way the mechanical-acoustical coupled eigenmodes of any piping system can be obtained. These eigenmodes are used to determine the response of the system to various sources (acoustical sources or forces exciting directly the structure). Equations have been written in the hypothesis that acoustical wave lengths remain large compared to the diameter of the pipe. Indeed this is largely verified in almost practical cases. The method has been checked by an experiment performed on the GASCOGNE loop at D.E.M.T. The piping system under test consist of a tube with four elbows. The circuit is ended at each extremity by a large vessel which performs acoustical isolation by generating modes for the pressure. Excitation of the circuit is caused by a valve located near the downstream vessel. This provide an efficient localised broad band acoustical source. The comparison between the test results and the calculations has shown that the low frequency resonant characteristics of the pipe and the vibrational amplitude at various flow-rates can be correctly predicted [fr

  20. SEALING LARGE-DIAMETER CAST-IRON PIPE JOINTS UNDER LIVE CONDITIONS

    Energy Technology Data Exchange (ETDEWEB)

    Kiran M. Kothari, Gerard T. Pittard

    2004-01-01

    Utilities in the U.S. operate over 75,000 km (47,000 miles) of old cast-iron pipes for gas distribution. The bell-and-spigot joints that connect pipe sections together tend to leak as these pipes age. Current repair practices are costly and highly disruptive. The objective of this program is to design, test and commercialize a robotic system capable of sealing multiple cast iron bell and spigot joints from a single pipe entry point. The proposed system will perform repairs while the pipe remains in service by traveling through the pipe, cleaning each joint surface, and installing a stainless-steel sleeve lined with an epoxy-impregnated felt across the joint. This approach will save considerable time and labor, avoid traffic disruption, and eliminate any requirement to interrupt service to customers (which would result in enormous expense to utilities). Technical challenges include: (1) repair sleeves must compensate for diametric variation and eccentricity of cast-iron pipes; (2) the assembly must travel long distances through pipes containing debris; (3) the pipe wall must be effectively cleaned in the immediate area of the joint to assure good bonding of the sleeve; and (4) an innovative bolt-on entry fitting is required to conduct repair operations on live mains. The development effort is divided into eleven tasks. Task 1--Program Management and Task 2--were completed in prior quarters while Task 3--Design and Fabricate Ratcheting Stainless-Steel Repair Sleeves has progressed to installing prototype sleeves in cast iron test pipe segments. Efforts in this quarter continued to focus on Tasks 4--8, with significant progress made in each. Task 4 (Design, Fabricate and Test Patch Setting Robotic Train) progressed to the design of the control electronics and pneumatic system to inflate the bladder robotic patch setting module. Task 5 (Design & Fabricate Pipe-Wall Cleaning Robot Train with Pan/Zoom/Tilt Camera) continued with additional in-pipe testing required to