WorldWideScience

Sample records for extruded cable insulation

  1. Tailored sPP/Silica Nanocomposite for Ecofriendly Insulation of Extruded HVDC Cable

    Directory of Open Access Journals (Sweden)

    Bin Dang

    2015-01-01

    Full Text Available Cross-linked polyethylene (XLPE is a thermosetting material that cannot be recycled at the end of its lifetime. This study investigated the potential of syndiotactic polypropylene (sPP/silica as an ecofriendly extruded insulation system for HVDC cables. We investigated the morphology, Fourier transform infrared, and thermal, thermomechanical, and electrical behaviors of sPP modified with 0.5–3% nanosilica. We found that the silica/sPP nanocomposite without cross-linking offered a suitable mechanical modulus at room temperature and sufficient intensity at high temperatures, and adding nanosilica modified by a silane coupling agent to the sPP resulted in significant DC resistivity and space charge improvement. The optimal nanosilica content in the sPP was determined by balancing the mechanical and thermomechanical characteristics and the DC resistivity. The sPP/silica nanocomposite reported here shows great potential as a candidate insulation material for future ecofriendly extruded HVDC cables.

  2. New class of additives to inhibit tree growth in solid extruded cable insulation

    Energy Technology Data Exchange (ETDEWEB)

    Devins, J C; Rzad, S J; Reed, C W; Bartosh, D K; Stines, T W

    1976-03-01

    There is now substantial evidence that in many dielectric failures of solid polyolefinic and other polymeric materials the final disruption may be preceded by the long-time progressive development of a three-dimensional pattern of irregular, sometimes (though not always) carbonized hollow channels diverging from a central stem, and that the ultimate failure follows one of these channels. These minute channels are referred to as ''trees'' and the phenomenon as ''treeing.'' Research conducted from May to Sept. 1975 on techniques for evaluating tree growth and on the development of additives to inhibit tree growth in solid extruded polymeric insulation for electric cables is reported. (LCL)

  3. Power cables with extruded insulation and their accessories for rated voltages from 1 kV (Um = 1,2 kV) up to 30 kV (Um = 36 kV) - Part 1: Cables for rated voltages of 1 kV (Um = 1,2 kV) and 3 kV (Um = 3,6 kV)

    CERN Document Server

    International Electrotechnical Commission. Geneva

    2004-01-01

    Specifies the construction, dimensions and test requirements of power cables with extruded solid insulation for rated voltages of 1 kV (Um = 1,2 kV) and 3 kV (Um = 3,6 kV) for fixed installations such as distribution networks or industrial installations. This standard includes cables which exhibit properties of reduced flame spread, low levels of smoke emission and halogen-free gas emission when exposed to fire. Cables for special installation and service conditions are not included, for example cables for overhead networks, the mining industry, nuclear power plants (in and around the containment area), submarine use or shipboard application. The main changes with respect to the first edition relate to insulation and oversheath thickness requirements, and inclusion of constructions and requirements for halogen free cables with reduced flame propagation and low levels of smoke emission.

  4. Post-Treatment Process of Extruded Insulation for 400 kV DC High Voltage Cable%400kV直流高压电缆绝缘挤塑后处理工艺

    Institute of Scientific and Technical Information of China (English)

    王坤; 杨德亮; 陆根生

    2013-01-01

    XLPE material is adopted as insulation of most 400 kV DC high voltage cables,but low molecular additives in material become weakness when suffering DC voltage withstanding test,which leads to low yields.The research of post-treatment extruded insulation for 400 kV DC high voltage cable is carried out.The experiment results of low molecular content in XLPE before and after treatment are compared.As a result the post-treatment processing conditions are cleared leading to the yields of finished products being increased from 65 % to 90 %.%400 kV直流高压电缆大多采用交联聚乙烯(XLPE)材料作为绝缘,材料中低分子添加物影响直流耐压试验通过,造成产品成品率较低.为此,针对400 kV直流高压电缆绝缘挤塑后处理工艺开展了研究,通过对处理前后材料中低分子物质含量的检测,明确了后处理工艺条件,产品成品率由65%提高到90%.

  5. Results of the CESI-CPRI research on extruded cables under DC voltage

    Energy Technology Data Exchange (ETDEWEB)

    Mosca, W.

    1988-10-01

    This paper describes extensive feasibility studies (involving power frequency withstand, partial discharge, short and long duration stress, lighting impulse and polarity reversal tests) on the the use of extruded DC cables for HVDC links. The results indicate that: either XLPe or EPr insulated cables, although not optimized for DC, show dielectric performances under DC stress that may be considered satisfactory (a mean working stress of around 25 kV/mm appears a realistic figure to be attained with proper materials and manufacturing technology); the behaviour under transient stress seems satisfactory (a fundamental role is played by the absence of defects and by the quality of the interfaces between inner/outer semiconductive screen and main insulation); a suitable protection to prevent moisture penetration in the insulation must be provided in order to avoid a significant reduction in cable dielectric performances (the use of a laminated protective covering could be in an interesting solution).

  6. Repairing Damaged Power-Cable Insulation

    Science.gov (United States)

    Baker, G. E.

    1984-01-01

    Simple method saves time, money, and material. In new method cable remains in place while new insulation is applied to damaged portion. Method results in new terminations with safety factor equal to that of any portion of cable.

  7. Development of an improved extruded dielectric cable rated 230 kV

    Energy Technology Data Exchange (ETDEWEB)

    Blais, L D; Traut, R T; Bolden, G N

    1977-05-01

    Work performed on developing an improved 230 kV extruded solid dielectric cable, the techniques of jointing such cables and the testing of terminations suitable for operation at that voltage level are described. Difficulties were encountered during manufacture in applying the semi-conducting extruded conductor shield. A new higher melt point compound solved the problem. A joint capable of operating at the 230 kV level was developed but showed a deficiency under voltage impulse testing while the conductor was at elevated temperature. A reduction in contract scope terminated this effort. Two terminals rated for 230 kV were found to be commercially available from domestic manufacturers. The limited testing performed showed them to be compatible with the cable cross-linked polyethylene insulation and electrically sound under 60 Hertz testing. No direct voltage or impulse voltage testing was performed on the terminations. A sample circuit, consisting of cable and joint, was subjected to impulse voltages at both room temperature and normal conductor operating temperature of 90/sup 0/C. While the cable only was able to withstand voltage impulses in excess of the Basic Impulse Level (BIL) at room temperature, it failed at BIL while conductor was heated to 90/sup 0/C. In like manner, a cable and joint circuit was assembled. Similar voltages were impressed at room temperature without incident. The joint failed at 90/sup 0/C conductor temperature. Cable, joint and termination were assembled in a simulated circuit and subjected to conductor loading to elevate temperature while 60 Hz voltages in excess of normal operating levels were continuously applied.

  8. 46 CFR 111.60-21 - Cable insulation tests.

    Science.gov (United States)

    2010-10-01

    ...-GENERAL REQUIREMENTS Wiring Materials and Methods § 111.60-21 Cable insulation tests. All cable for electric power and lighting and associated equipment must be checked for proper insulation resistance to... 46 Shipping 4 2010-10-01 2010-10-01 false Cable insulation tests. 111.60-21 Section...

  9. Insulation Degradation Diagnostic Technology to XLPE Cable

    Science.gov (United States)

    Uchida, Katsumi; Okamoto, Tatsuki

    XLPE power cables have been in use for long time now and some of them are approaching 30 years of their designed lifetime. However, under the present severe economic situation, it is necessary to use the existing apparatus as long as possible. So, degradation diagnostic methods with high reliability are needed earnestly. This paper explains the insulation degradation mechanism of XLPE power cables and the newest diagnostic methods on each voltage class. In 3.3-77kV classes, fairly high extents of the cable accidents depend on the water-tree degradation. For 3.3-6.6kV class cables, on-line diagnostic methods with high reliability to detect bridged water-trees have been developed and put in practical use. And, for 22-77kV classes, two promising off-line diagnostic methods to detect un-bridged water-trees have begun to carry out in on-site tests.

  10. Equipment qualification research test of electrical cable with factor splices and insulation rework: Test no. 2, report no. 1

    Science.gov (United States)

    Minor, E. E.; Furgal, D. T.

    1982-09-01

    Electric cables with flame retardant chemically crosslinked polyolefin extruded insulation containing factory made center conductor splices and insulation repairs manufactured by the Rockbestos Company were used in a methodology test of the IEEE Standard 383-1974. Cable specimens were radiation aged at a low dose rate and then thermally aged to simulate a 40 year containment exposure. After aging, the specimens were subjected to LOCA radiation and a 33 day steam and chemical spray exposure. The cables were electrically loaded and functioned without failure during and after LOCA steam and chemical spray exposure. Insulation resistance measurements were taken during the exposure sequence. Subsequence to the exposures, hipot and mandrel bend tests were conducted. To determine the most severe cable aging sequence, cable insulation material samples were subjected to varied aging exposure to observe sequence related and dose rate related material degradation. A dose rate effect was observed.

  11. Problems of Automatic Test of Insulation in Cable Production

    Science.gov (United States)

    Red'ko, V. V.; Leonov, A. P.; Red'ko, L. A.; Bolgova, V. A.

    2016-01-01

    The article presents a qualitative and quantitative assessment of cable products insulation defects that can be reliably detected by means of the electrosparking control during the cable production process. The performance potential of technological control is evaluated: the limit of reliable detection of defective places in insulation taking into account the technical capabilities of modern control devices is marked.

  12. INVESTIGATION OF LOSSES IN INSULATION OF HIGH-VOLTAGE CABLES WITH XLPE INSULATION

    Directory of Open Access Journals (Sweden)

    L.A. Shchebeniuk

    2016-09-01

    Full Text Available In this paper the authors calculate the losses in insulation system cable with XLPE-polyethylene as a solid dielectric insulation and with semiconductor polyethylene used as a conductor screen and a insulation screen. The paper is devoted to the investigation of losses in the insulation system of high- voltage XLPE-cables. The line of XLPE-cables in group running horizontally, provided that the cables are of equal diameter and emit equal losses. It is limited to the following: the air flow around the cables may be necessary restricted by proximity to next cables. The dielectric losses are voltage depended and related to the insulation system materials being used. All current in this insulation system are complex quantities containing both real (Re(I and imaginary (Im(I parts. Values of the loss factor of the insulation system at power frequency tgd are given astgd = Re(I/Im(I. It was proposed the quantities criterion of the loss factor of the insulation system to high voltage XLPE-cables. The work is devoted to creation of a method for calculation of the current rating of high-voltage cables in conditions function.

  13. Chemical oxidation of cable insulating oil contaminated soil

    NARCIS (Netherlands)

    Jinlan Xu,; Pancras, T.; Grotenhuis, J.T.C.

    2011-01-01

    Leaking cable insulating oil is a common source of soil contamination of high-voltage underground electricity cables in many European countries. In situ remediation of these contaminations is very difficult, due to the nature of the contamination and the high concentrations present. Chemical oxidati

  14. Design, manufacture, test and delivery of a 230 kV extruded irradiated crosslinked polyethylene cable. Final report

    Energy Technology Data Exchange (ETDEWEB)

    None

    1978-01-01

    A project was initiated to develop a 230 kV solid dielectric cable for use in underground transmission. The dielectric is to be polyethylene, crosslinked by electron bombardment. Compared to the more conventional chemically crosslinked polyethylene, the irradiated cable is expected to contain less sensitive defects and thus be more suitable for a 230 kV rating. A toroidally shaped diode was developed to provide a uniform radiation dose to a thick-walled coaxial cable. The diode is to receive an output wave form obtained by ringing a Marx generator into a peaking capacitor. Initial evaluation of the toroidal diode was performed on thin plaques and tapes of insulating and semi-conducting polyethylene polymers. Additionally, some miscellaneous ethylene plastics were briefly investigated. Using a 4.8 MV Van de Graaff pulse generator in conjunction with several diode configurations, 15 to 35 kV extruded HMW-PE cables were irradiated. Dose rate, temperature, and pressure effects were evaluated. It was found that with limited dose rate it was possible to produce excellent crosslink density and uniformity at room temperature and atmospheric pressure. A subsequent 60 Hz voltage endurance test on an irradiated cable sample indicated it had long term, high stress capability. An engineering study conducted to determine an acceptable irradiator system design is reported. It was estimated that a 7 MV peak voltage at a rate of 2 to 3 pulse/sec can be provided by a Marx generator/peaking capacitor and should be capable of crosslinking a polyethylene wall thickness of approximately 2.5 cm. Based on the accumulated test results and on the performance of the 7 MV irradiator predicted, it appears feasible to continue the work effort into the next scheduled phase.

  15. Insulation systems for superconducting transmission cables

    DEFF Research Database (Denmark)

    Tønnesen, Ole

    1996-01-01

    the electrical insulation is placed outside both the superconducting tube and the cryostat. The superconducting tube is cooled by liquid nitrogen which is pumped through the hollow part of the tube.2) The cryogenic dielectric design, where the electrical insulation is placed inside the cryostat and thus is kept...

  16. Propylene based systems for high voltage cable insulation applications

    Energy Technology Data Exchange (ETDEWEB)

    Hosier, I L; Vaughan, A S; Swingler, S G [ECS, University of Southampton, Highfield, Southampton, SO17 1BJ (United Kingdom); Cozzarini, L, E-mail: ILH@ecs.soton.ac.u [DMRN, University of Trieste, Via Valerio 6A, 34127 Trieste (Italy)

    2009-08-01

    Crosslinked polyethylene (XLPE) remains the material of choice for extruded high voltage cables, possessing excellent thermo-mechanical and electrical properties. However, it is not easily recyclable posing questions as to its long term sustainability. Whilst both polyethylene and polypropylene are widely recycled and provide excellent dielectric properties, polypropylene has significantly better mechanical integrity at high temperatures than polyethylene. However, while isotactic polypropylene is too stiff at room temperature for incorporation into a cable system, previous studies by the authors have indicated that this limitation can be overcome by using a propylene-ethylene copolymer. Whilst these previous studies considered unrelated systems, the current study aims to quantify the usefulness of a series of related random propylene-ethylene co-polymers and assesses their potential for replacing XLPE.

  17. Determination of sensitivity for in-process control of cable product insulation

    Science.gov (United States)

    Redko, V. V.; Starikova, N. S.; Redko, L. A.; Vavilova, G. V.

    2015-04-01

    This article presents current methods of cable insulation control. The new method which allows to improve reliability of cable insulation control was offered. The cable model with several types of defects was developed by using Comsol Myltiphysics software. Minimal sizes of defects which can be detected by using given in-process control method.

  18. High-voltage cable insulation online monitoring in coal mine based on pattern recognition

    Science.gov (United States)

    Zhao, Yongmei; Li, Junfeng; Wu, Lingjie; Wang, Yanwen

    2017-03-01

    The single-phase grounding fault is the main electrical fault types of the mine power grid. A new cable insulation online monitoring based on pattern recognition is proposed, in case single-phase grounding fault in coal mine. Firstly, using the pattern recognition method, the insulation state of the cable is divided into three types: "good insulation" and "insulation decline symmetrically" and "insulation decline asymmetrically". Then the cables with "insulation decline asymmetrically" can be further analysed and calculated and its insulation parameter value can be determined. The algorithm is simulated and verified. Simulation result shows that: The zero-sequence voltage and each phase voltage and the zero-sequence current of each cable are taken in the coal mine high-voltage system, and the insulation parameter value of each cable can be calculated accurately by using the pattern recognition method.

  19. 30 CFR 75.517-2 - Plans for insulation of existing bare power wires and cables.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Plans for insulation of existing bare power... Equipment-General § 75.517-2 Plans for insulation of existing bare power wires and cables. (a) On or before December 31, 1970, plans for the insulation of existing bare power wires and cables installed prior to...

  20. Nonlinear Dielectric Response of Water Treed XLPE Cable Insulation

    Energy Technology Data Exchange (ETDEWEB)

    Hvidsten, Sverre

    1999-07-01

    Condition assessment of XLPE power cables is becoming increasingly important for the utilities, due to a large number of old cables in service with high probability of failure caused by water tree degradation. The commercial available techniques are generally based upon measurements of the dielectric response, either by time (polarisation/depolarisation current or return voltage) or frequency domain measurements. Recently it has been found that a high number of water trees in XLPE insulated cables causes the dielectric response to increase more than linearly with increasing test voltage. This nonlinear feature of water tree degraded XLPE insulation has been suggested to be of a great importance, both for diagnostic purposes, and for fundamental understanding of the water tree phenomenon itself. The main purpose of this thesis have been to study the nonlinear feature of the dielectric response measured on watertreed XLPE insulation. This has been performed by dielectric response measurements in both time and frequency domain, numerical calculations of losses of simplified water tree models, and fmally water content and water permeation measurements on single water trees. The dielectric response measurements were performed on service aged cable samples and laboratory aged Rogowski type objects. The main reason for performing laboratory ageing was to facilitate diagnostic testing as a function of ageing time of samples containing mainly vented water trees. A new method, based upon inserting NaC1 particles at the interface between the upper semiconductive screen and the insulation, was found to successfully enhance initiation and growth of vented water trees. AC breakdown strength testing show that it is the vented water trees that reduce the breakdown level of both the laboratory aged test objects and service aged cable samples. Vented water treeing was found to cause the dielectric response to become nonlinear at a relatively low voltage level. However, the measured

  1. The heat insulating properties of potato starch extruded with addition of chosen by- products of food industry

    Directory of Open Access Journals (Sweden)

    Zdybel Ewa

    2014-12-01

    Full Text Available The study was aimed at determination of time of heat transition through the layer of quince, apple, linen, rose pomace and potato pulp, as well as layer of potato starch and potato starch extruded with addition of above mentioned by-products. Additionally the attempt of creation a heat insulating barrier from researched raw material was made. The heat conductivity of researched materials was dependent on the type of material and its humidity. Extruded potato starch is characterized by smaller heat conductivity than potato starch extruded with addition of pomace. The obtained rigid extruded starch moulders were characterized by higher heat insulating properties than the loose beads. It is possible to use starch and by-products of food industry for production of heat insulating materials.

  2. Compilation of radiation damage test data cable insulating materials

    CERN Document Server

    Schönbacher, H; CERN. Geneva

    1979-01-01

    This report summarizes radiation damage test data on commercially available organic cable insulation and jacket materials: ethylene- propylene rubber, Hypalon, neoprene rubber, polyethylene, polyurethane, polyvinylchloride, silicone rubber, etc. The materials have been irradiated in a nuclear reactor to integrated absorbed doses from 5*10/sup 5/ to 5*10/sup 6/ Gy. Mechanical properties, e.g. tensile strength, elongation at break, and hardness, have been tested on irradiated and non-irradiated samples. The results are presented in the form of tables and graphs, to show the effect of the absorbed dose on the measured properties. (13 refs).

  3. Thermal property of insulation material for HTS power cable

    Science.gov (United States)

    Choi, Yeon Suk; Kim, D. L.; Shin, D. W.; Hwang, S. D.

    2012-06-01

    The thermal property of insulation material is essential in developing a high temperature superconductor (HTS) power cable operating at around liquid nitrogen temperature. The accurate estimate of the heat flux is difficult in the nonmetallic materials because nonmetallic materials have a high thermal resistance and low temperature gradient along the specimen. The objective of the present work is to develop a precise instrument for measuring the thermal conductivity of insulating materials over a temperature range of 30 K to approximately the room temperature by using a cryocooler. The thermal conductivity of Teflon is measured and the accuracy confirmation is carried out by comparing published data. In addition, the experimental results of apparent thermal conductivity of polypropylene laminated paper (PPLP) are presented and the temperature dependency is also discussed

  4. Determining the Number of Parallel RC Branches in Polarization / Depolarization Current Modeling for XLPE Cable Insulation

    Directory of Open Access Journals (Sweden)

    S. Sulaiman

    2017-06-01

    Full Text Available An important element in the electric power distribution system is the underground cable. However continuous applications of high voltages unto the cable, may lead to insulation degradations and subsequent cable failure. Since any disruption to the electricity supply may lead to economic losses as well as lowering customer satisfaction, the maintenance of cables is very important to an electrical utility company. Thus, a reliable diagnostic technique that is able to accurately assess the condition of cable insulation operating is critical, in order for cable replacement exercise to be done. One such diagnostic technique to assess the level of degradation within the cable insulation is the Polarization / Depolarization Current (PDC analysis. This research work attempts to investigate PDC behaviour for medium voltage (MV cross-linked polyethylene (XLPE insulated cables, via baseline PDC measurements and utilizing the measured data to simulate for PDC analysis. Once PDC simulations have been achieved, the values of conductivity of XLPE cable insulations can be approximated. Cable conductivity serves as an indicator to the level of degradation within XLPE cable insulation. It was found that for new and unused XLPE cables, the polarization and depolarization currents have almost overlapping trendlines, as the cable insulation’s conduction current is negligible. Using a linear dielectric circuit equivalence model as the XLPE cable insulation and its corresponding governing equations, it is possible to optimize the number of parallel RC branches to simulate PDC analysis, with a very high degree of accuracy. The PDC simulation model has been validated against the baseline PDC measurements.

  5. Designing Predictive Diagnose Method for Insulation Resistance Degradation of the Electrical Power Cables from Neutral Insulated Power Networks

    Science.gov (United States)

    Dobra, R.; Pasculescu, D.; Risteiu, M.; Buica, G.; Jevremović, V.

    2017-06-01

    This paper describe some possibilities to minimize voltages switching-off risks from the mining power networks, in case of insulated resistance faults by using a predictive diagnose method. The cables from the neutral insulated power networks (underground mining) are designed to provide a flexible electrical connection between portable or mobile equipment and a point of supply, including main feeder cable for continuous miners, pump cable, and power supply cable. An electronic protection for insulated resistance of mining power cables can be made using this predictive strategy. The main role of electronic relays for insulation resistance degradation of the electrical power cables, from neutral insulated power networks, is to provide a permanent measurement of the insulated resistance between phases and ground, in order to switch-off voltage when the resistance value is below a standard value. The automat system of protection is able to signalize the failure and the human operator will be early informed about the switch-off power and will have time to take proper measures to fix the failure. This logic for fast and automat switch-off voltage without aprioristic announcement is suitable for the electrical installations, realizing so a protection against fires and explosion. It is presented an algorithm and an anticipative relay for insulated resistance control from three-phase low voltage installations with insulated neutral connection.

  6. 49 CFR 234.267 - Insulation resistance tests, wires in trunking and cables.

    Science.gov (United States)

    2010-10-01

    ... be made between all conductors and ground, between conductors in each multiple conductor cable, and between conductors in trunking. Insulation resistance tests shall be performed when wires, cables, and... be made annually. (d) A circuit with a conductor having an insulation resistance of less than...

  7. ESTIMATION CRITERIA FOR DEGREE OF PAPER-IMPREGNATED INSULATED POWER CABLE AGEING

    Directory of Open Access Journals (Sweden)

    G.V. Bezprozvannych

    2013-09-01

    Full Text Available Correlation between parameters characterizing mechanical and thermal ageing of paper-impregnated insulation of medium voltage power cables is revealed. On the basis of linear and exponential regression analysis at confidence coefficient of 0.95, critical values of dielectric loss tangent of wrapping and phase insulation corresponding to the cable life termination are found.

  8. Space charge build-up in XLPE-cable with temperature gradient

    DEFF Research Database (Denmark)

    Holbøll, Joachim; Henriksen, Mogens; Hjerrild, Jesper

    2000-01-01

    Space charge build-up in standard XLPE insulated AC cables has been studied under varying temperature and field conditions. The cables were triple-extruded with the inner semicon on a solid aluminum conductor, 5.5mm XLPE-insulation and an outer semicon. The cables were stressed up to 15kV/mm DC...

  9. Heat Transfer through Cable Insulation of Nb–Ti Superconducting Magnets Operating in He II

    CERN Document Server

    Granieri, P P

    2013-01-01

    The operation of Nb–Ti superconducting magnets in He II relies on superfluidity to overcome the severe thermal barrier represented by the cable electrical insulation. In wrapped cable insulations, like those used for the main magnets of the Large Hadron Collider (LHC) particle accelerator, the micro-channels network created by the insulation wrappings allows to efficiently transfer the heat deposited or generated in the cable to the He bath. In this paper, available experimental data of heat transfer through polyimide electrical insulation schemes are analyzed. A steady-state thermal model is developed to describe the insulation of the LHC main dipole magnets and the Enhanced Insulation proposed for the High Luminosity LHC upgrade (HL-LHC), according to the relevant geometric parameters. The model is based on the coupled mechanisms of heat transfer through the bulk of the dielectric insulation and through micro-channels between the insulation tapes. A good agreement is found between calculations and tests p...

  10. HEAT TESTS OF POWER CABLES WITH XLPE INSULATION AT DIRECT VOLTAGES UP TO 110 KV

    Directory of Open Access Journals (Sweden)

    T.Yu. Antonets

    2015-12-01

    Full Text Available In this paper, experiment for determining the temperature difference between the elements of cable and in the open air is considered. The formation of a three cables laid in a plane with different spacing between adjacent cables. Tests to heat of cables for XLPE-polyethylene are used as a solid dielectric insulation. The line to XLPE-cables in group running horizontally, provided that the cables are of equal diameter and emit equal losses. It is limited to the following: the air flow around the cables may be necessary restricted by proximity to next cables. When single-core cables are installed in parallel the load current may not share equally between the parallel cables. This is because a significant proportion of the impedance of large conductors is due to self reactance and mutual reactance. Hence the spacing and relative location of each cable will have an effect on the current sharing. Calculation for each cable configuration is necessary. Possibility of using for determining the thermal properties of XLPE-cables a sheath applied over the cable surface with coefficient convection heat transfer between cable surface and the air region about it of equal zero. The work is devoted to creation of a method for calculation of the current rating of high-voltage cables in conditions function.

  11. Insulation Diagnosis of Service Aged XLPE Power Cables Using Statistical Analysis and Fuzzy Inference

    Institute of Scientific and Technical Information of China (English)

    LIU Fei; JIANG Pingkai; LEI Qingquan; ZHANG Li; SU Wenqun

    2013-01-01

    Cables that have been in service for over 20 years in Shanghai,a city with abundant surface water,failed more frequently and induced different cable accidents.This necessitates researches on the insulation aging state of cables working in special circumstances.We performed multi-parameter tests with samples from about 300 cable lines in Shanghai.The tests included water tree investigation,tensile test,dielectric spectroscopy test,thermogravimetric analysis (TGA),fourier transform infrared spectroscopy (FTIR),and electrical aging test.Then,we carried out regression analysis between every two test parameters.Moreover,through two-sample t-Test and analysis of variance (ANOVA) of each test parameter,we analyzed the influences of cable-laying method and sampling section on the degradation of cable insulation respectively.Furthermore,the test parameters which have strong correlation in the regression analysis or significant differences in the t-Test or ANOVA analysis were determined to be the ones identifying the XLPE cable insulation aging state.The thresholds for distinguishing insulation aging states had been also obtained with the aid of statistical analysis and fuzzy clustering.Based on the fuzzy inference,we established a cable insulation aging diagnosis model using the intensity transfer method.The results of regression analysis indicate that the degradation of cable insulation accelerates as the degree of in-service aging increases.This validates the rule that the increase of microscopic imperfections in solid material enhances the dielectric breakdown strength.The results of the two-sample t-Test and the ANOVA indicate that the direct-buried cables are more sensitive to insulation degradation than duct cables.This confirms that the tensile strength and breakdown strength are reliable functional parameters in cable insulation evaluations.A case study further indicates that the proposed diagnosis model based on the fuzzy inference can reflect the comprehensive

  12. Application of Optical Diagnosis to Aged Low-Voltage Cable Insulation in Nuclear Plants

    Science.gov (United States)

    Katagiri, Junichi; Takezawa, Yoshitaka; Shouji, Hiroshi

    We have developed a novel non-destructive optical diagnosis technique for low-voltage cable insulations used in nuclear power plants. The key features of this diagnosis are the use of two wavelengths to measure the change in reflective absorbance (ΔAR), the use of polarized light to measure crystallinity and the use of element volatilizing to measure fluorescence. Chemical kinetics is used to predict the lifetimes of the cable insulations. When cable insulations darken and harden by time degradation, the ΔAR and depolarization parameters increase. This means that the cross-linking density in the cable insulations increases due to deterioration reactions. When the cross-linking density of insulation increases, its elasticity, corresponding to the material's life, increases. Similarly, as the crystallinity increases due to the change in the high-order structure of the insulating resin caused by irradiation, its elongation property decreases. The elongation property of insulation is one of the most important parameters that can be used to evaluate material lifetimes, because it relates to elasticity. The ΔAR correlated with the elongation property, and the correlation coefficient of an accelerated experiment using model pieces was over 0.9. Thus, we concluded that this optical diagnosis should be applied to evaluate the degradation of cable insulations used in nuclear power plants.

  13. 49 CFR 236.108 - Insulation resistance tests, wires in trunking and cables.

    Science.gov (United States)

    2010-10-01

    ... dry. Insulation resistance tests shall be made between all conductors and ground, and between conductors in each multiple conductor cable, and between conductors in trunking, when wires or cables are... annually. (c) In no case shall a circuit be permitted to function on a conductor having an...

  14. The insulation coordination and surge arrester design for HTS cable system in Icheon substation

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Hansang, E-mail: Hansang80@korea.ac.kr [School of Railway and Electrical Engineering, Kyungil University, Hayang-eup, Gyeongsan-si, Gyeongsangbuk-do 712-701 (Korea, Republic of); Yoon, Dong-Hee [Department of New and Renewable Energy, Kyungil University, Hayang-eup, Gyeongsan-si, Gyeongsangbuk-do 712-701 (Korea, Republic of); Lee, Seung-Ryul [Korea Electrotechnology Research Institute, Naeson-dong, Uiwang-si, Gyeonggi-do 437-080 (Korea, Republic of); Yang, Byeong-Mo [Korea Electric Power Research Institute, Munji-dong, Yuseong-gu, Daejeon 305-760 (Korea, Republic of); Jang, Gilsoo, E-mail: gjang@korea.ac.kr [School of Electrical Engineering, Korea University, Anam-dong 5-ga, Seongbuk-gu, Seoul 136-713 (Korea, Republic of)

    2013-01-15

    Highlights: ► It is necessary to study lightning response of the HTS cable. ► The analytic model has been developed for the HTS cable in the Icheon substation. ► Well-designed surge arrester has been verified through PSCAD/EMTDC simulations. -- Abstract: This paper proposes an insulation coordination and surge arrester design for HTS (High-Temperature Superconducting) cable system in Icheon substation in Korea. In the aspect of the economic analysis, since the HTS cable is very expensive, the insulation coordination to prevent the dielectric breakdown caused by the lightning surge should be considered carefully. Also, in the aspect of the power system reliability, since the HTS cable has much more capacity compared than conventional power cables and the ripple effect from the HTS cable failure may lead to the wide area blackout, an intensive study for insulation coordination from lightning surge is one of the most important considerations. In this paper, the insulation coordination for lightning surge is verified using HTS cable and power equipment models and the design of the proper surge arrester is proposed.

  15. Influence of Frequency Converters on Insulation of Power Supply Cables at Oil-Producing Stations

    Directory of Open Access Journals (Sweden)

    D. I. Zalizny

    2011-01-01

    Full Text Available The paper considers consequences of negative frequency converter influence on insulation of  power supply cables used for submersible installations of electric-centrifugal pumps at oil-producing stations. The possible approaches to the solution of the problem are proposed on the basis of a harmonic analysis of actually measured voltages and currents in a cable.  

  16. Heat transfer through cable insulation of Nb-Ti superconducting magnets operating in He II

    Science.gov (United States)

    Granieri, P. P.

    2013-01-01

    The operation of Nb-Ti superconducting magnets in He II relies on superfluidity to overcome the severe thermal barrier represented by the cable electrical insulation. In wrapped cable insulations, like those used for the main magnets of the Large Hadron Collider (LHC) particle accelerator, the micro-channels network created by the insulation wrappings allows to efficiently transfer the heat deposited or generated in the cable to the He bath. In this paper, available experimental data of heat transfer through polyimide electrical insulation schemes are analyzed. A steady-state thermal model is developed to describe the insulation of the LHC main dipole magnets and the Enhanced Insulation proposed for the High Luminosity LHC upgrade (HL-LHC), according to the relevant geometric parameters. The model is based on the coupled mechanisms of heat transfer through the bulk of the dielectric insulation and through micro-channels between the insulation tapes. A good agreement is found between calculations and tests performed at different applied pressures and heating configurations. The model allows identifying the heat fluxes in the cable cross-section as well as the dimensions of the micro-channels. These dimensions are confirmed by microscope images of the two insulations schemes.

  17. Anomalous aging phenomena in a crosslinked polyolefin cable insulation

    Science.gov (United States)

    Celina, M.; Gillen, K. T.; Wise, J.; Clough, R. L.

    1996-11-01

    The radiation-thermal degradation of a commercial crosslinked polyolefin (XLPO) cable insulation material was investigated as a function of dose rate and temperature in the range of 22-120°C. Degradative changes in the material were monitored by ultimate elongation, density, gel content, O 2 consumption, infrared spectroscopy, and differential scanning calorimetry. Mechanical aging surprisingly occurred most rapidly at the lowest temperatures. This unusual phenomenon was corroborated by chemical measurements (gel content and density). When samples that had been irradiated at ambient temperature were subsequently annealed at elevated temperatures, recovery of mechanical properties and concurrent changes in gel content and density were observed. The involvement of residual radical species and hydroperoxide intermediates as well as the importance of molecular mobility in the semi-crystalline XLPO as contributors to these anomalous behaviors were evaluated and discussed. The observed inverse temperature effect, where polymer degradation occurs more rapidly at lower temperatures, represents an example in which material aging and life time prediction cannot be handled by conventional approaches, such as the commonly applied Arrhenius methodology.

  18. ESTIMATION OF INDUCED CURRENTS IN THE SHIELDS OF ELECTRICAL POWER CABLES WITH XLPE INSULATION

    Directory of Open Access Journals (Sweden)

    I. V. Oleksyuk

    2015-01-01

    Full Text Available Electrical power cables with Cross-Linked Polyethylene Insulation (XLPE-insulation are currently utilized in projects of the electric-power supply systems of modern facilities. However, the higher costs, the incomplete design, installation and maintenance normativetechnical basis as well as certain constructional features of the XLPE-insulated cable lines hinder their large-scale implementation.The cables with XLPE insulation are mostly produced in a single-conductor core version being provided with a composite copper shield whose cross-section may vary while the electric conductor cross-section remains uniform. Earthing the cable shields on both sides causes the flow of electricity in them. The course of operational service of the XLPE-insulated cable lines revealed the following fact – the currents induced in the cable shields can run up to the levels commeasurable with those in the conductor-cores themselves. That, in its turn, leads to electrical safety-level reduction, cable lines failure, and economic losses. The currents induced in the shields may occur both in symmetric (normal and emergency and asymmetric operating modes of the power grid with values of the induced currents reaching 80 % of the conducting core currents. Many factors affect the level of the current induced in the shield: the midpoint conductor modes, the values of the core longitudinal currents in the normal and emergency operating modes, failure mode, the cross-section area of the shield, the cables mutual disposition, and the distance between them.The paper claims experimental existence conformation of the cable-shield current induced by that in the conductor-core and demonstrates its measured value. The author establishes that induction of dangerous currents in the cable shields demands elaboration of measures on reducing their level.

  19. The Application of Novel Polypropylene to the Insulation of Electric Power Cable (3)

    Science.gov (United States)

    Kurahashi, Kiyoshi; Matsuda, Yoshiji; Miyashita, Yoshitsugu; Demura, Tsuyoshi; Ueda, Asakiyo; Yoshino, Katsumi

    Having higher melting temperature than polyethylene, polypropylene has been expected as insulation material for power cable. But isotactic polypropylene used generally is unsuitable as cable insulation because it shows poor flexibility, low breakdown strength due to growing spherulites, and so on. But stereoregular syndiotactic polypropylene (s-PP) newly developed with metallocene catalyst shows quite different properties from i-PP. The authors had investigated the basic properties of s-PP and the initial properties as a cable which was manufactured using s-PP insulation, in the previous paper. As the results of this, it was revealed that s-PP had superior thermal and electrical properties to cross-linked polyethylene and the s-PP insulation cable showed satisfactory initial properties. However, in order to apply to an actual cable, the properties must be maintainable over 30 years after construction. In this paper, we estimated the long term and remaining properties for s-PP insulation cable. A series of experiments on long term properties gave following results. (1) S-PP cable shows longer life over 30 years. (2) The breakdown strength of s-PP cable after long term experiment equal to 30 years is slightly lower than initial breakdown strength, but it’s sufficient as remaining property. Furthermore, water-tree resistivity of s-PP was investigated and it was revealed that s-PP significantly suppressed the water tree propagation compared with XLPE. These results suggested that s-PP cable would be available as next generation cable.

  20. A new application area for fullerenes: voltage stabilizers for power cable insulation.

    Science.gov (United States)

    Jarvid, Markus; Johansson, Anette; Kroon, Renee; Bjuggren, Jonas M; Wutzel, Harald; Englund, Villgot; Gubanski, Stanislaw; Andersson, Mats R; Müller, Christian

    2015-02-01

    Fullerenes are shown to be efficient voltage-stabilizers for polyethylene, i.e., additives that increase the dielectric strength of the insulation material. Such compounds are highly sought-after because their use in power-cable insulation may considerably enhance the transmission efficiency of tomorrow's power grids. On a molal basis, fullerenes are the most efficient voltage stabilizers reported to date.

  1. Vacuum-Insulated, Flexible Cryostats for Long HTS Cables: Requirements, Status, and Prospects.

    Energy Technology Data Exchange (ETDEWEB)

    Gouge, Michael J [ORNL; Demko, Jonathan A [ORNL; Roden, Mark L [ORNL; Maguire, J. F. [American Superconductor Corporation, Westborough, MA; Weber, C. S. [SuperPower Incorporated, Schenectady, New York

    2008-01-01

    Several high temperature superconducting (HTS) cable demonstration projects have begun operation on the electric grid in the last few years with the liquid nitrogen-cooled cable contained in one or more vacuum-insulated, flexible cryostats with lengths up to 600 meters. These grid demonstration projects are prototypes of the anticipated commercial market which will require superconducting cable lengths in the multiple kilometer range with the vacuum-jacketed cryostats in underground ducts providing acceptable thermal insulation for decades. The current state-of-the art for flexible cryostats (installation constraints, heat loads with a good and degraded vacuum, impact of cable bends, getter lifetime and reliability) is discussed. Further development needed to meet the challenging commercial HTS cable application is outlined.

  2. Heat transfer in electrical insulation of LHC cables cooled with superfluid helium

    CERN Document Server

    Meuris, C; Leroy, D; Szeless, Balázs

    1999-01-01

    The electrical insulation of the Large Hadron Collider (LHC) cables constitutes a thermal barrier between the conductor and the superfluid helium bath. This can prevent removal of the heat dissipated in the cable by the current rise in the dipoles or by the beam losses. The main experimental results, obtained with stacks of insulated conductors representing a piece of the actual coil, are given. The mock-ups vary only by the material composition and the structure of the electrical insulation. Analysis of the temperature distribution measured in the conductors as a function of the dissipated heat power makes it possible to determine the dominant heat transfer mode in each type of tested insulation and to classify these according to their permeability to superfluid helium. Thermal numerical modelling of the experimental mock-ups clarifies the heat transfer path in the complex structure of the insulation and enables calculation of values of the thermal quantities characteristic of each insulation. The results of...

  3. RELAXATIONS LOSSES IN POLYETHYLENE INSULATION OF COAXIAL CABLE STRUCTURE DURING AGING IN HIGH HUMIDITY CONDITIONS

    Directory of Open Access Journals (Sweden)

    G.V. Bezprozvannych

    2016-05-01

    Full Text Available Introduction. The presence of free moisture in power cables leading to the formation of tree structures - water treeing, which originate in the amorphous phase polyethylene and are a major cause of degradation of the polymer insulation. They represent the damage of the polymer size from several microns to 1 mm, developing technology for insulation defects under the combined action of the electric field and the moisture diffusing from the environment. Water treeing destroys the polymer chain, resulting in the formation of microcavities filled with moisture. The dynamics of water treeing and subtle properties largely depend on the composition, morphology of the polymer insulation, chemical nature of the defect, in which they originate. Due to the force of gravity in the water formed typical only for her region with locally ordered structure - clusters, which cause loss of relaxation. Purpose. Features presence of relaxation losses in high-frequency range in polyethylene insulation during aging in high humidity conditions of samples power and RF cables. Methodology. Samples of the power cable for the voltage of 35 kV with a cross-linked polyethylene insulation radial water-blocking protection from moisture and radio-frequency coaxial cable with thermoplastic insulation for 1440 hours in a humidity of 100%. The dielectric loss tangent measured resonance method before and after aging. Originality. Experimentally found evidence of the existence in the polymer cable insulation free water in the form of areas with locally ordered structure - clusters. It is found that the solid polyethylene insulation in the frequency dependence of dielectric loss tangent maximum relaxation shown one at 10 MHz in the initial state, and there are two additional frequency range 500 kHz - 5 MHz after moistening. For cross-linked polyethylene insulation characteristic of large width Δf of the frequency spectrum in which the observed relaxation losses. It is obvious that

  4. Thermal Insulation Performance of Flexible Piping for Use in HTS Power Cables

    Science.gov (United States)

    Fesmire, James E.; Augustynowicz, S. D.; Demko, J. A.; Thompson, Karen (Technical Monitor)

    2001-01-01

    High-temperature superconducting (HTS) cables that typically operate at temperatures below 80 K are being developed for power transmission. The practical application of HTS power cables will require the use of flexible piping to contain the cable and the liquid nitrogen coolant. A study of thermal performance of multilayer insulation (MLI) was conducted in geometries representing both rigid and flexible piping. This experimental study performed at the Cryogenics Test Laboratory of NASA Kennedy Space Center provides a framework for the development of cost-effective, efficient thermal insulation systems that will support these long-distance flexible lines containing HTS power cables. The overall thermal performance of the insulation system for a rigid configuration and for a flexible configuration, simulating a flexible HTS power cable, was determined by the steady-state liquid nitrogen boiloff method under the full range of vacuum levels. Two different cylindrically rolled material systems were tested: a standard MLI and a layered composite insulation (LCI). Comparisons of ideal MLI, MLI on rigid piping, and MLI between flexible piping are presented.

  5. Towards aging mechanisms of cross-linked polyethylene (XLPE) cable insulation materials in nuclear power plants

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Shuaishuai; Fifield, Leonard S.; Bowler, Nicola

    2016-12-19

    Cross-linked polyethylene (XLPE) cable insulation material undergoes simultaneous, accelerated thermal and gamma-radiation aging to simulate the long-term aging environment within nuclear power plants (NPPs). A variety of materials characterization tests, including scanning electron microscopy, thermo-gravimetric analysis, differential scanning calorimetry, oxidation induction time, gel-fraction and dielectric properties measurement, are conducted on pristine and differently aged XLPE samples. A preliminary model of one possible aging mechanism of XLPE cable insulation material under gamma radiation at elevated temperature of 115 °C is suggested.

  6. Investigation of aging effects in cross-linked polyethylene insulated cable using terahertz waves

    Science.gov (United States)

    Yan, Zhijin; Shi, Wei; Hou, Lei; Xu, Ming; Yang, Lei; Dong, Chengang; Li, Shengtao

    2017-01-01

    A method to detect the degree of aging in cross-linked polyethylene (XLPE) insulated cables, using terahertz (THz) waves, is reported in this letter. With increased aging time, the real permittivity decreases in the frequency range from 0.7 to 2.5 THz. The imaginary permittivity and absorption coefficient of unaged XLPE sample are larger than those of thermally aged XLPE insulated cables. These findings indicate that the aging degree of XLPE can be obtained by measuring its permittivity and absorption coefficient by THz waves.

  7. Safety research of insulating materials of cable for nuclear power generating station

    Science.gov (United States)

    Lee, C. K.; Choi, J. H.; Kong, Y. K.; Chang, H. S.

    1988-01-01

    The polymers PE, EPR, PVC, Neoprene, CSP, CLPE, EP and other similar substances are frequently used as insulation and protective covering for cables used in nuclear power generating stations. In order to test these materials for flame retardation, environmental resistance, and cable specifications, they were given the cable normal test, flame test, chemical tests, and subjected to design analysis and loss of coolant accident tests. Material was collected on spark tests and actual experience standards were established through these contributions and technology was accumulated.

  8. The Recovery of the Metal Insulation Cable in the Instrumentation of Nuclear Fuel Rod

    Energy Technology Data Exchange (ETDEWEB)

    Joung, Chang Young; Ahn, Sung Ho; Sim, Bong Sik; Lee, Chul Yong [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2010-10-15

    Mineral-insulated (MI) cables are widely used to prolong the instrumentation cable of instruments such as a thermocouple (TC), linear variable differential transformer (LVDT) and self-powered neutron detector (SPND), which are used to measure various irradiation characteristics of nuclear fuels and materials. MI cables are expected to be helpful for instrumentation of nuclear fuel and material irradiation because of their high electrical insulation, heat resistance and mechanical strength. The MI cable used to extend thermocouple wires is classified as the following: 1) For common metal types of thermocouples, the thermocouple extension wire is of substantially the same composition as the corresponding thermocouple type and it can offer advantages in cost or mechanical properties when used for the connection between a thermocouple and instruments. 2) For noble metal types of thermocouples, the thermocouple compensation wire is an entirely different alloy formulated to match the noble metal characteristics, which is necessary due to the high cost of noble metals. During the installation of an instrument, an MI cable damaged by impact must be recovered because it is difficult to change the entire thermocouple. And for MI cable recovery, it is necessary to develop the instrumentation technology of FTL. This paper described the experimental results of MI cable recovery, which consists of a removal test of the MI cable sheath and a joining test of the compensation of the wire and MI cable/ wire/compensation wire and sheath of MI cable/bushing, for carrying out irradiation tests of nuclear fuel and materials in the FTL facility of HANARO

  9. Development of 500-kV AC cable employing laminar insulation of other than conventional cellulosic paper

    Science.gov (United States)

    Bahder, G.; Eager, G. S., Jr.; Walker, J. J.; Dima, A. F.

    1980-09-01

    The results of an investigation to develop a 500 kV ac laminar dielectric power cable and joint having insulation with lower losses than conventional cellulosic paper insulation are presented. Background information is presented on proposed low loss synthetic and composite synthetic/cellulosic paper insulations. From these studies, fibrous polypropylene paper tape and cellulosic paper-polypropylene film-cellulosic paper composite paper (PPP) were chosen. Extensive testing of handwrapped cable models fabricated with each type of tape served to eliminate the fibrous polypropylene paper tape from further consideration. Cable model tests indicate that the PPP tape is satisfactory for insulation in 500 kV ac cable, and that oil impregnants now used in conventional cellulosic paper insulated cables are unsuitable, but that silicone oil with an additive is satisfactory for PPP tapes.

  10. Destruction behavior of hexabromocyclododecanes during incineration of solid waste containing expanded and extruded polystyrene insulation foams.

    Science.gov (United States)

    Takigami, Hidetaka; Watanabe, Mafumi; Kajiwara, Natsuko

    2014-12-01

    Hexabromocyclododecanes (HBCDs) have been used for flame retardation mainly in expanded polystyrene (EPS) and extruded polystyrene (XPS) insulation foams. Controlled incineration experiments with solid wastes containing each of EPS and XPS were conducted using a pilot-scale incinerator to investigate the destruction behavior of HBCDs and their influence on the formation of polybrominated dibenzo-p-dioxins and dibenzofurans (PBDD/DFs). EPS and XPS materials were respectively blended with refuse derived fuel (RDF) as input wastes for incineration. Concentrations of HBCDs contained in the EPS- and XPS-added RDFs, were 140 and 1100 mg kg(-1), respectively. In which γ-HBCD was dominant (68% of the total HBCD content) in EPS-added RDF and α-HBCD accounted for 73% of the total HBCDs in XPS-added RDF. During the incineration experiments with EPS and XPS, primary and secondary combustion zones were maintained at temperatures of 840 °C and 900 °C. The residence times of waste in the primary combustion zone and flue gas in the secondary combustion zone was 30 min and three seconds, respectively. HBCDs were steadily degraded in the combustion chambers and α-, β-, and γ-HBCD behaved similarly. Concentration levels of the total HBCDs in the bag filter exit gas for the two experiments with EPS and XPS were 0.7 and 0.6ngmN(-3), respectively. HBCDs were also not detected (polystyrene is increased in the input wastes just to make sure of formation prevention and emission control of PBDD/DFs. The concentrations and congener patterns of PCDD/DFs and dl-PCBs in the samples during the three experiments were not affected by an addition of HBCDs.

  11. A 245 kV XLPE (X-Linked PolyEthylene) cable systems. 245 kV XLPE kabelsystemen

    Energy Technology Data Exchange (ETDEWEB)

    Schoonakker, P.; Willems, H.M.J. (Hoogspannings Research Laboratorium, Nederlandse Kabel Fabriek BV (NKF), Waddinxveen (Netherlands))

    1991-12-01

    High-voltage extruded cables up to and including 170 kV have acquired a good service record in the Netherlands during the last decade. These cables are rapidly replacing the conventional paper-insulated cables. The next step is the introduction of extruded cable systems for 245 kV. The Dutch Cable Factory (NKF) started the development of a 245 kV XLPE cable system several years ago. The development is based on well-defined design parameters, a controlled production, a sound test program, and a good quality control system. 12 figs., 1 tab.

  12. Heat transfer through Rutherford superconducting cable with novel pattern of polyimide electrical insulation in pressurized superfluid helium environment

    Science.gov (United States)

    Chorowski, Maciej; Polinski, Jaroslaw; Strychalski, Michal

    2012-06-01

    Future LHC accelerator luminosity upgrade will increase a beam losses heat deposition in the superconducting magnet coils. Main barrier of the heat evacuation from the coils made of Rutherford type cables is a cable electrical insulation. The insulation is made of polyimide tapes wrapped around the cable in a special configuration. Presently used insulation wrapping schemes constitute very good electrical insulation with relatively low heat transport ability. Therefore a new insulation wrapping schemes with enhanced helium permeability and adequate dielectric properties have been developed at CERN. An experimental comparative study of heat transfer perpendicular to the Rutherford type cable, for an old and new insulation wrapping schemes have been accomplished at Wroclaw University of Technology. The tests have been performed in pressurized superfluid helium conditions, and at 60 MPa of the sample applied external pressure simulating the Lorentz forces. This paper presents the measurements methodology and gives experimental results.

  13. Flexible Aerogel as a Superior Thermal Insulation for High Temperature Superconductor Cable Applications

    Science.gov (United States)

    White, S.; Demko, J.; Tomich, A.

    2010-04-01

    High temperature superconducting (HTS) cables are an advanced technology that can both strengthen and improve the national electrical distribution infrastructure. HTS cables require sufficient cooling to overcome inherent low temperature heat loading. Heat loads are minimized by the use of cryogenic envelopes or cryostats. Cryostats require improvement in efficiency, reliability, and cost reduction to meet the demanding needs of HTS conductors (1G and 2G wires). Aspen Aerogels has developed a compression resistant aerogel thermal insulation package to replace compression sensitive multi-layer insulation (MLI), the incumbent thermal insulation, in flexible cryostats for HTS cables. Oak Ridge National Laboratory tested a prototype aerogel package in a lab-scale pipe apparatus to measure the rate of heat invasion. The lab-scale pipe test results of the aerogel solution will be presented and directly compared to MLI. A compatibility assessment of the aerogel material with HTS system components will also be presented. The aerogel thermal insulation solution presented will meet the demanding needs of HTS cables.

  14. The Application of Novel Polypropylene to the Insulation of Electric Power Cable (2)

    Science.gov (United States)

    Miyashita, Yoshitsugu; Demura, Tsuyoshi; Ueda, Asakiyo; Someya, Akira; Kawahigashi, Masaki; Murakami, Tsuyoshi; Matsuda, Yoshiji; Kurahashi, Kiyoshi; Yoshino, Katsumi

    The authors had investigated the basic properties of newly developed stereoregular syndiotactic polypropylene (s-PP) which had been synthesized with homogeneous metallocene catalyst, in the previous paper. As the result of this, it was revealed that s-PP had superior thermal and electrical properties to cross-linked polyethylene (XLPE) which was adopted as conventional insulating material for high voltage power cable. In this paper, we estimated the possibility to apply s-PP to the actual power cable from the viewpoint of long-term thermal durability and processability. Consequently, it was found that the thermal stability of s-PP could be significantly improved by adding both hindered phenol and sulfur antioxidants, and wide molecular weight distribution of s-PP contributed to good processability during extrusion. On the basis of these results, 600V and 22kV class cables with insulation of s-PP were manufactured. Successfully manufactured cables proposed that s-PP could be available to electric power cable. Lightning Impulse and AC breakdown strength of both cables at the temperature range of RT to 120°C will be discussed.

  15. Insulation Heat Shrinkage for Small-Size Silane XLPE Insulated Cable%小规格硅烷交联聚乙烯绝缘电缆的绝缘热收缩

    Institute of Scientific and Technical Information of China (English)

    陆正荣

    2011-01-01

    The reasons of insulation heat shrinkage are explained through the phenomena description and theoretic analysis of the insulation heat shrinkage of small-size Si-XLPE cables with 6 mm2 and below of conductor diameters.It is found that the heat shrinkage performance of the cable insulation can be controlled through choosing proper raw materials and equipment, controlling the cooling temperature, and choosing appropriate extruding tools.%通过对6 mm2及以下小规格硅烷交联聚乙烯(Si-XL-PE)电缆绝缘热收缩现象的阐述、原理分析,来解释绝缘热收缩的原因,得出通过原材料及设备的选择,冷却温度的控制及挤出模具的选择,可控制电缆绝缘热收缩性能的结论.

  16. Development, testing and application of extruded polystyrene foam (XPS) insulation with improved thermal properties; Polystyrol-Extruderschaum mit verbesserten waermetechnischen Eigenschaften - Entwicklung, Pruefung und Anwendung

    Energy Technology Data Exchange (ETDEWEB)

    Bunge, Friedhelm [Forschung und Entwicklung Dow Building Solutions, Horgen (Switzerland); Merkel, Holger [Anwendungstechnik Dow Building Solutions, Schwalbach (Germany)

    2011-02-15

    Improved extruded polystyrene foam (XPS) insulation with lower thermal conductivity has been developed. This enables meeting the increased requirements for sustainable building insulation with better material efficiency. The proven mechanical and hygro-thermal properties of XPS insulation are maintained. This first product generation has been developed primarily for external perimeter insulation of basement walls and floors as well as for the insulation of cavity walls. The CO{sub 2} foaming technology meets the sustainability requirements for building products. (Copyright copyright 2011 Ernst and Sohn Verlag fuer Architektur und technische Wissenschaften GmbH and Co. KG, Berlin)

  17. Understanding Electrical Treeing Phenomena in XLPE Cable Insulation Adopting UHF Technique

    Science.gov (United States)

    Sarathi, Ramanujam; Nandini, Arya; Danikas, Michael G.

    2011-03-01

    A major cause for failure of underground cables is due to formation of electrical trees in the cable insulation. A variety of tree structure can form from a defect site in cable insulation viz bush-type trees, tree-like trees, fibrillar type trees, intrinsic type, depending on the applied voltage. Weibull studies indicate that a higher applied voltage enhances the rate of tree propagation thereby reducing the life of cable insulation. Measurements of injected current during tree propagation indicates that the rise time and fall time of the signal is of few nano seconds. In the present study, an attempt has been made to identify the partial discharges caused due to inception and propagation of electrical trees adopting UHF technique. It is realized that UHF signal generated during tree growth have signal bandwidth in the range of 0.5-2.0 GHz. The formation of streamer type discharge and Townsend type discharges during tree inception and propagation alters the shape of the tree formed. The UHF signal generated due to partial discharges formed during tree growth were analyzed adopting Ternary plot, which can allow one to classify the shape of tree structure formed.

  18. Improved diagnosis of MV paper-insulated cables using signal analysis

    DEFF Research Database (Denmark)

    Villefrance, Rasmus; Holbøll, Joachim T.; Sørensen, John Aasted;

    1999-01-01

    With the purpose of improving the PD estimation accuracy and the degree of automation of the measurements, the following study is carried out. Initially, a library of different discharge pulses and actual background noise from a selection of cables is established. The library is then used...... for the estimation of PD-signals from a parametric model leading to reduction of the noise superimposed on the PD-signals and thus to improved PD-detection. The applicability of these methods is discussed in relation to mobile systems for the assessment of cable insulation condition....

  19. Modeling of the polymerization process of the insulating layer of cable thermocouples

    Directory of Open Access Journals (Sweden)

    Olga Iashutina

    2017-01-01

    Full Text Available A mathematical model describing the main physical processes occurring during thermal processing of cable thermocouples (CT during their production is presented. The polymerization of the insulating layer is taken into account in the conditions of its intense heating. The developed mathematical model allows to carry out calculations of heat transfer processes under the conditions of substantial heterogeneity of cable thermocouple structure. The computational experiments carried out have established significant differences in the characteristics of heat transfer in CT in the presence of thermoelectrodes with differing thermophysical characteristics.

  20. Reducing current noise in cryogenic experiments by vacuum-insulated cables

    CERN Document Server

    Mykkänen, E; Kemppinen, A; Krause, C; Drung, D; Nissilä, J; Manninen, A J

    2016-01-01

    We measure the current noise of several cryogenic cables in a pulse tube based dilution refrigerator at frequencies between about 1~mHz and 50~kHz. We show that vibration-induced noise can be efficiently suppressed by using vacuum-insulated cables between room temperature and the 2nd pulse tube stage. A noise peak below 4 fA at the 1.4~Hz operation frequency of the pulse tube, and a white noise density of 0.44 fA/\\sqrt{Hz} in the millihertz range are obtained.

  1. Electrical and Mechanical Performance of an Enhanced Cable Insulation Scheme for Superconducting Magnets

    CERN Document Server

    Fessia, P; Luzieux, S; Tommasini, D; Gerardin, A; Guinchard, M; Regis, F; Sgobba, S; Zaghloul, A

    2010-01-01

    New polyimide cable insulation schemes improving the cooling of Nb-Ti superconducting coils were recently developed to face the severe heat loads at which the next generation of superconducting accelerator magnets will work. In order to qualify the new insulation, a test campaign was realized to assess both its electrical and mechanical features with respect to the standard LHC insulation. The electrical tests assessed the dielectric strength and inter-turn leakage current to be satisfactory. The mechanical tests investigated the insulation thickness under load and the stress relaxation at ambient temperature, thus providing essential information for the magnetic and mechanical design of the final focusing magnets for the LHC upgrade phase I.

  2. On the Degradation Mechanism of Low-Voltage Underground Cable with Poly(Vinyl Chloride) Insulation

    Science.gov (United States)

    Tawancy, H. M.; Hassan, M.

    2016-06-01

    A study has been undertaken to determine the degradation mechanism leading to localized short-circuit failures of an underground low-voltage cable with PVC insulation. It is shown that that the insulation of outer sheath and conductor cores has been cracked by thermal degradation involving dehydrochlorination, oxidation, and loss of plasticizers leading to current leakage between the cores. Most evidence points out that overheating due to poor connection of copper wires as well as a chemically active soil has caused the observed degradation.

  3. Reconfigurable Buoyant Cable Antenna with Improved Gain

    Science.gov (United States)

    2010-07-28

    consists of a number of connected streamer cable sections, which each comprise a mechanical jacket surrounding a hollow core enclosing seismic sensor and...of insulation. A buoyancy layer/ jacket is either injection molded or extruded in place onto the core to make the final structure a solid object...systems: [0008] U.S. Patent No. 5,745,436, issued April 28, 1998, to Bittleston, discloses a semi-dry marine seismic streamer cable that

  4. Experimental study of radiation induced electromotive force effects on mineral insulated cables

    Science.gov (United States)

    Van Nieuwenhove, R.; Vermeeren, L.

    2003-11-01

    Measurements of radiation induced electromotive force (RIEMF) effects on mineral insulated cables in a pure gamma field and in a combined neutron and gamma field are presented and compared to model calculations. The effect of materials in the immediate surroundings of the cable, as predicted by the model calculations, is clearly demonstrated. In a fission reactor environment, delayed current contributions due to the neutron activation and subsequent beta emission in base materials as well as in impurities such as Mn are clearly observed and are well reproduced by model calculations. The prediction of the gamma induced current component was severely complicated by its strong sensitivity to the detailed geometry and the spectrum and the directivity of the gamma field. Although the RIEMF effect on MI cables can therefore in general not be completely eliminated, some guidelines are provided to minimize them.

  5. Microstructural characterization of XLPE electrical insulation in power cables: determination of void size distributions using TEM

    Science.gov (United States)

    Markey, L.; Stevens, G. C.

    2003-10-01

    In an effort to progress in our understanding of the ageing mechanisms of high voltage cables submitted to electrical and thermal stresses, we present a quantitative study of voids, the defects which are considered to be partly responsible for cable failure. We propose a method based on large data sets of transmission electron microscopy (TEM) observations of replicated samples allowing for the determination of void concentration distribution as a function of void size in the mesoscopic to microscopic range at any point in the cable insulation. A theory is also developed to calculate the effect of etching on the apparent size of the voids observed. We present the first results of this sort ever obtained on two industrial cables, one of which was aged in an AC field. Results clearly indicate that a much larger concentration of voids occur near the inner semiconductor compared to the bulk of the insulation, independently of ageing. An effect of ageing can also be seen near the inner semiconductor, resulting in an increase in the total void internal surface area and a slight shift of the concentration curve towards larger voids, with the peak moving from about 40 nm to about 50 nm.

  6. Treeing phenomenon of thermoplastic polyethylene blends for recyclable cable insulation materials

    Directory of Open Access Journals (Sweden)

    Lunzhi Li

    2017-02-01

    Full Text Available Owing to its good recyclability and low processing energy consumption, non-crosslinked polyethylene blends (e.g. LLDPE-HDPE blends are considered as one of potential environmental-friendly substitutions for crosslinked polyethylene (XLPE as cable insulation material. Although extensive work has been performed for measuring the basic dielectric properties, there is a lack of the investigations on the aging properties for such a material system, which hinders the evaluation of reliability and lifetime of the material for cable insulation. In this paper, we study the electric aging phenomenon of 0.7LLDPE-0.3HDPE blending material by investigating the treeing behavior, and its comparison with XLPE and LLDPE. Treeing tests show that the 0.7LLDPE-0.3HDPE blends have lower probability for treeing as well as smaller treeing dimensions. Further thermal analysis and microstructure study results suggest that the blends exhibit larger proportion of thick lamellae and higher crystallinity with homogeneously-distributed amorphous region, which is responsible for good anti-treeing performance. Our finding provides the evidence that the 0.7LLDPE-0.3HDPE blends exhibits better electric-aging-retardance properties than XLPE, which may result in a potential application for cable insulation.

  7. Dynamic space charge behaviour in polymeric DC cables

    DEFF Research Database (Denmark)

    Rasmussen, Claus Nygaard; Holbøll, Joachim; Henriksen, Mogens

    2002-01-01

    The use of extruded insulation for DC cables involves a risk of local electric field enhancement, caused by a space charge build-up within the dielectric. In this work, the theory of charge generation and transport in polymers is applied in a numerical computer model in order to predict the forma......The use of extruded insulation for DC cables involves a risk of local electric field enhancement, caused by a space charge build-up within the dielectric. In this work, the theory of charge generation and transport in polymers is applied in a numerical computer model in order to predict...

  8. Analysis of electrical tree propagation in XLPE power cable insulation

    Energy Technology Data Exchange (ETDEWEB)

    Bao Minghui, E-mail: baominghui@21cn.co [College of Electrical and Electronic Engineering, Huazhong University of Science and Technology, Wuhan (China); Yin Xiaogen; He Junjia [College of Electrical and Electronic Engineering, Huazhong University of Science and Technology, Wuhan (China)

    2011-04-01

    Electrical treeing is one of the major breakdown mechanisms for solid dielectrics subjected to high electrical stress. In this paper, the characteristics of electrical tree growth in XLPE samples have been investigated. XLPE samples are obtained from a commercial XLPE power cable, in which electrical trees have been grown from pin to plane in the frequency range of 4000-10,000 Hz, voltage range of 4-10 kV, and the distances between electrodes of 1 and 2 mm. Images of trees and their growing processes were taken by a CCD camera. The fractal dimensions of electric trees were obtained by using a simple box-counting technique. The results show that the tree growth rate and fractal dimension was bigger when the frequency or voltage was higher, or the distance between electrodes was smaller. Contrary to our expectation, it has been found that when the distance between electrodes changed from 1 to 2 mm, the required voltage of the similar electrical trees decreased only 1or 2 kV. In order to evaluate the difficulties of electrical tree propagation in different conditions, a simple energy threshold analysis method has been proposed. The threshold energy, which presents the minimum energy that a charge carrier in the well at the top of the tree should have to make the tree grow, has been computed considering the length of electrical tree, the fractal dimension, and the growth time. The computed results indicate that when one of the three parameters of voltage, frequency, and local electric field increase, the trends of energy threshold can be split into 3 regions.

  9. Gradient Changing Morphology Research of Cross-linked Polyethylene Thick Insulation of 110 kV Power Cable

    Institute of Scientific and Technical Information of China (English)

    ZHU Ai-rong; LIU Ying; CAO Xiao-long

    2006-01-01

    The thick insulation layer of 110 kV XLPE power cables will result in the gradient changing morphology with the radius due to crosslinking process and cooling of the XLPE insulation. In this paper, the morphology of cross-linked polyethylene (XLPE) insulation of 110 kV cable and the uniforming effect of the heating process on it are researched by the differential scanning calorimetry (DSC) and X-ray diffraction (WAXD). The middle layer morphology structures of insulation produced by normal technology are of better uniform, while the crystallinity of the inner and outer layer of the insulation is lower than that of the middle one.The melting enthalpy △Hm of materials displays the difference of the crystal morphologies sensitively. The difference of crystallizing morphology in different layers of the high-voltage power cable insulation can be improved by heating process. But the uniforming of morphology of the insulation by heating process requires sufficient temperature and time. The effect of the on-line stress-relaxation equipment used widely by cable works now should be doubted. The test results of WAXD reveal that thermal stress changes the interplanar distances in the crystal region. So the radical stress in the insulation is tensile mainly.

  10. Cable insulation thickness uncertainty evaluation%电缆绝缘厚度不确定度的测评

    Institute of Scientific and Technical Information of China (English)

    王冬梅

    2013-01-01

    wire and cable insulation quality directly affects the use and production of security cable, in order to ensure that the cable safety,it is necessary not to timing of cable testing,to ensure that the cable quality,reduce security risks,the better the cable used in real life.However,cable detection easily in the cable testing work can not be carried out smoothly uncertain factors,it is necessary for uncertainty evaluation,to maximize the cable.The thickness of insulation and insulation thickness detection of uncertain importance degree evaluation combined with the analysis of cable,insulation thickness uncertainty factors and solution strategies for test.%  电线电缆绝缘层质量如何直接关系着电缆生产和使用安全,为了确保电缆安全,有必要不定时对电缆进行检测,以保证电缆质量,减少安全隐患,更好的将电缆应用于实际生活。然而,电缆检测中易受不确定因素的影响使电缆检测工作无法顺利进行,这就需要对不确定度进行测评,以最大限度的发挥电缆作用。文中结合电缆绝缘厚度检测概况和绝缘厚度不确定度测评的重要性,用试验来分析绝缘厚度不确定度影响因素和解决策略。

  11. Heat transfer through the electrical insulation of Nb3Sn cables

    CERN Document Server

    Granieri, P; van Weelderen, R

    2014-01-01

    For the LHC upgrade projects, CERN will rely on the Nb3Sn technology to build high field dipole and quadrupole superconducting magnets. In the frame of this R&D program, cooling studies are carried out to determine the heat extraction from this new type of accelerator magnets and the relevant quench limits. In this paper we present and discuss experimental results of heat transfer through the electrical insulation of Nb3Sn cables. A cable-stack was prepared using fiberglass sleeves and CTD-101K impregnation resin. Two different measurement methods were compared, consisting of instrumenting the sample before or after the vacuum impregnation. The tests were performed both in 1.9 K superfluid and 4.2 K liquid helium baths, using different heating configurations. We also present results of the numerical model developed to reproduce the experimental results.

  12. Hysteresis Model for Oil-Soaked Insulation in Flat HTDC-Cable

    DEFF Research Database (Denmark)

    Larsen, Poul Scheel

    1999-01-01

    A phenomenological unsteady, one-dimensional model is presented for the description of the hysteresis phenomenon of accommodated oil volume versus pressure observed when a cable is pressurized with oil and subsequently depressurized. The model includes the elastic deformation of oil channels......, giving no hysteresis, and the elastic deformation of the solid structure in the porous paper insulation due to changes in pressure. The latter process give rise to hysteresis. The high pressure in inflow areas near oil channels during filling opens the pores, hence facilitates inflow, while the low...

  13. 电缆绝缘老化的诊断技术%Diagnostic Technique of Cable Insulation Aging

    Institute of Scientific and Technical Information of China (English)

    肖林华

    2012-01-01

    本文简单介绍了电缆绝缘老化的几种原理,对电力电缆试品的工频耐压测试及超低频耐压测试进行对比分析,探讨如何发现电缆绝缘存在老化,正确把握电缆的运行情况,确保电力供电安全性和可靠性.%This paper briefly introduces several principles of the cable insulation aging, and makes comparative analysis for ultra-low-frequency withstand voltage test and power frequency withstand voltage test of power cable testing products, discusses ways of finding cable insulation aging and correctly grasping the operation of the cable to ensure the safety and reliability of electricity supply.

  14. Reliability prediction of I&C cable insulation materials by DSC and Weibull theory for probabilistic safety assessment of NPPs

    Energy Technology Data Exchange (ETDEWEB)

    Santhosh, T.V., E-mail: santutv@barc.gov.in [Reactor Safety Division, Bhabha Atomic Research Centre (India); Gopika, V. [Reactor Safety Division, Bhabha Atomic Research Centre (India); Ghosh, A.K. [Raja Ramanna Fellow, Department of Atomic Energy (India); Fernandes, B.G. [Department of Electrical Engineering, Indian Institute of Technology Bombay (India); Dubey, K.A. [Radiation Technology Development Division, Bhabha Atomic Research Centre (India)

    2016-01-15

    Highlights: • An approach for time dependent reliability prediction of I&C cable insulation materials for use in PSA of NPP has been developed based on OIT and OITp measurement, and Weibull theory. • OITs were determined from the measured OITp based on the fundamental thermodynamics principles, and the correlations obtained from DSC and FTIR are in good agreement with the EAB. • The SEM of thermal and irradiated samples of insulation materials was performed to support the degradation behaviour observed from OIT and EAB measurements. • The proposed methodology has been illustrated with the accelerated thermal and radiation ageing data on low voltage cables used in NPP for I&C applications. • The time dependent reliability predicted from the OIT based on Weibull theory will be useful in incorporating the cable ageing into PSA of NPP. - Abstract: Instrumentation and control (I&C) cables used in nuclear power plants (NPPs) are exposed to various deteriorative environmental effects during their operational lifetime. The factors consisting of long-term irradiation and enhanced temperature eventually result in insulation degradation. Monitoring of the actual state of the cable insulation and the prediction of their residual service life consist of the measurement of the properties that are directly proportional to the functionality of the cables (usually, elongation at break is used as the critical parameter). Although, several condition monitoring (CM) and life estimation techniques are available, currently there is no any standard methodology or an approach towards incorporating the cable ageing effects into probabilistic safety assessment (PSA) of NPPs. In view of this, accelerated thermal and radiation ageing of I&C cable insulation materials have been carried out and the degradation due to thermal and radiation ageing has been assessed using oxidation induction time (OIT) and oxidation induction temperature (OITp) measurements by differential scanning

  15. A Novel Electrical Insulating Material for 275 kV High-Voltage HTS Cable with Low Dielectric Loss

    Science.gov (United States)

    Hayakawa, N.; Nishimachi, S.; Maruyama, O.; Ohkuma, T.; Liu, J.; Yagi, M.

    2014-05-01

    In the case of high temperature superconducting (HTS) power transmission cables at high voltage operation, the electrical insulation technique in consideration of the dielectric loss reduction becomes crucial. In this paper, we focused on a Tyvek/polyethylene (PE) sheet, instead of the conventional polypropylene laminated paper (PPLP). We obtained the dielectric characteristics (epsilonr, tanδ) and partial discharge inception strength (PDIE) of PPLP, Tyvek and Tyvek/PE. We pointed out that the dielectric loss of 275 kV HTS cable with Tyvek/PE insulation will be reduced to 21 % of that with PPLP, and the total electrical loss including the AC loss will be reduced to 41 %.

  16. Testing to evaluate synergistic effects from LOCA environments. Test IX. Simultaneous mode; cables, splice assemblies, and electrical insulation samples

    Energy Technology Data Exchange (ETDEWEB)

    Thome, F.V.

    1978-04-01

    This test was conducted to complement Test VIII which was a sequential test of cables, cable splices, and insulation samples. In this test, the generic LOCA environments (radiation, temperature, pressure, chemical spray) were simulated and simultaneously applied to the test items. There were no failures of any assemblies and all were able to function at rated current and voltage throughout the entire test. An additional parameter, dissipation factor, was monitored in this test and when used in conjunction with capacitance, provided a better indication of insulation degradation.

  17. Long duration immersion tests on cross-linked polyethylene insulated MV cables; Essais de longue duree en immersion de cables HTA isoles au polyethylene reticule

    Energy Technology Data Exchange (ETDEWEB)

    Leroy, J.H.; Pinet, A. [Electricite de France, 92 - Clamart (France). Direction des Etudes et Recherches; Simeon, E. [Alcatel, 75 - Paris (France); Audoux, C.; FOndeur, J.H.

    1996-12-31

    Although the MV cable used in France possesses a high degree of radial and longitudinal watertightness, it has been subjected to further investigations to assess its behaviour when the insulation is in presence of water. The selected test methods consist mainly of ageing the cable in water at 50 deg. C under 4 times its rated voltage, with the dielectric residual strength being measured after 6 months, one year and two years. It appears that a drop in the residual voltage strength occurs chiefly during the first 6 months of ageing. The detailed results are given in this report. Finally, aspects relating to the standardization of such tests are also mentioned. (authors)

  18. Radiation Induced Aging Effects in Polymeric Cable Insulators at CERN. Compilation of the DSC and ATR-FTIR data on irradiated CERN cables.

    CERN Document Server

    Sorin, I

    2009-01-01

    This second part of the Report on Radiation Induced Aging Effects in Polymeric Cable Insulators at CERN [1] summarizes in a tabulated form all the experimental DSC results obtained in this work, concerning the life-time evaluation of the selected CERN cables irradiated in different conditions. Several examples of DSC curves and ATR-FTIR spectra were included to support the future polymeric materials analysis. Information on the experimental conditions, the instruments, the basic concept of life-time evaluation using the DSC data, as well as the examples of data processing and interpretation are presented and discussed in reference [1].

  19. Designing and Implementation a Lab Testing Method for Power Cables Insulation Resistance According with STAS 10411-89, SR EN ISO/CEI/17025/2005

    Science.gov (United States)

    Dobra, R.; Pasculescu, D.; Marc, G.; Risteiu, M.; Antonov, A.

    2017-06-01

    Insulation resistance measurement is one of the most important tests required by standards and regulations in terms of electrical safety. Why these tests are is to prevent possible accidents caused by electric shock, damage to equipment or outbreak of fire in normal operating conditions of electrical cables. The insulation resistance experiment refers to the testing of electrical cable insulation, which has a measured resistance that must be below the imposed regulations. Using a microcontroller system data regarding the insulation resistance of the power cables is acquired and with SCADA software the test results are displayed.

  20. Morphology and crystalline-phase-dependent electrical insulating properties in tailored polypropylene for HVDC cables

    Science.gov (United States)

    Zha, Jun-Wei; Yan, Hong-Da; Li, Wei-Kang; Dang, Zhi-Min

    2016-11-01

    Polypropylene (PP) has become one promising material to potentially replace the cross-link polyethylene used for high voltage direct current cables. Besides the isotactic polypropylene, the block polypropylene (b-PP) and random polypropylene (r-PP) can be synthesized through the copolymerization of ethylene and propylene molecules. In this letter, the effect of morphology and crystalline phases on the insulating electrical properties of PP was investigated. It was found that the introduction of polyethylene monomer resulted in the formation of β and γ phases in b-PP and r-PP. The results from the characteristic trap energy levels indicated that the β and γ phases could induce deep electron traps which enable to capture the carriers. And the space charge accumulation was obviously suppressed. Besides, the decreased electrical conductivity was observed in b-PP and r-PP. It is attributed to the existence of deep traps which can effectively reduce the carrier mobility and density in materials.

  1. Effects of radiation types and dose rates on selected cable-insulating materials

    Science.gov (United States)

    Hanisch, F.; Maier, P.; Okada, S.; Schönbacher, H.

    A series of radiation tests have been carried out on halogen-free cable-insulating and cable-sheathing materials comprising commercial LDPE, EPR, EVA and SIR compounds. samples were irradiated at five different radiation sources, e.g. a nuclear reactor, fuel elements, a 60Co source, and in the stray radiation field of high-energy proton and electron accelerators at CERN and DESY. The integrated doses were within 50-5000 kGy and the dose rates within 10 mGy/s-70 Gy/s. Tensile tests and gel-fraction measurements were carried out. The results confirm that LDPEs are very sensitive to long-term ageing effects, and that important errors exceeding an order of magnitude can be made when assessing radiation damage by accelerated tests. On the other hand, well-stabilized LDPEs and the cross-linked rubber compounds do not show large dose-rate effects for the values given above. Furthermore, the interpretation of the elongation-at-break data and their relation to gel-fraction measurements show that radiation damage is related to the total absorbed dose irrespective of the different radiation types used in this experiment.

  2. Investigations of a mechanically failed cable insulation used in indoor conditions

    CERN Document Server

    Setnescu, R; Lungulescu, E M; Ilie, S; Marinescu, V; Mares, G; Setnescu, T

    2011-01-01

    This paper presents the investigation work on different polymeric materials used as insulation materials of conductors in a multicore instrumentation cable. Among differently colored materials, only the white one presented cracks after a few years of use. Isothermal and non-isothermal DSC measurements were performed on initial (non-used) and aged (in service used or laboratory aged) materials as well as on raw materials in order to characterize their stability and the ageing state after storage, use in service or laboratory ageing. As shown by the oxidation induction time values, a pronounced antioxidant loss occurred for all materials during storage or service; plus a strong effect of the ambient light on stability was observed for the white insulation material. Around 3\\% of filler, consisting mainly of TiO(2) particles (as revealed by SEM-XRF elemental analysis), was found in the white material. The higher degradability of the white material can be related to both the photocatalytic effect of the TiO(2) pa...

  3. The characteristics of electrical trees in the inner and outer layers of different voltage rating XLPE cable insulation

    Science.gov (United States)

    Xie, Ansheng; Li, Shengtao; Zheng, Xiaoquan; Chen, George

    2009-06-01

    The statistical initiation and propagation characteristics of electrical trees in cross-linked polyethylene (XLPE) cables with different voltage ratings from 66 to 500 kV were investigated under a constant test voltage of 50 Hz/7 kV (the 66 kV rating cable is from UK, the others from China). It was found that the characteristics of electrical trees in the inner region of 66 kV cable insulation differed considerably from those in the outer region under the same test conditions; however, no significant differences appeared in the 110 kV rating cable and above. The initiation time of electrical trees in both the inner and the outer regions of the 66 kV cable is much shorter than that in higher voltage rating cables; in addition the growth rate of electrical trees in the 66 kV cable is much larger than that in the higher voltage rating cables. By using x-ray diffraction, differential scanning calorimetry and thermogravimetry methods, it was revealed that besides the extrusion process, the molecular weight of base polymer material and its distribution are the prime factors deciding the crystallization state. The crystallization state and the impurity content are responsible for the resistance to electrical trees. Furthermore, it was proposed that big spherulites will cooperate with high impurity content in enhancing the initiation and growth processes of electrical trees via the 'synergetic effect'. Finally, dense and small spherulites, high crystallinity, high purity level of base polymer material and super-clean production processes are desirable for higher voltage rating cables.

  4. The characteristics of electrical trees in the inner and outer layers of different voltage rating XLPE cable insulation

    Energy Technology Data Exchange (ETDEWEB)

    Xie Ansheng; Li Shengtao; Zheng Xiaoquan [State Key Laboratory of Electrical Insulation and Power Equipment, Xi' an Jiaotong University, Xi' an 710049 (China); Chen, George, E-mail: sli@mail.xjtu.edu.c, E-mail: xieansheng@gmail.co, E-mail: xqzheng@mail.xjtu.edu.c, E-mail: gc@ecs.soton.ac.u [School of Electronics and Computer Science, University of Southampton, Southampton SO17 1BJ (United Kingdom)

    2009-06-21

    The statistical initiation and propagation characteristics of electrical trees in cross-linked polyethylene (XLPE) cables with different voltage ratings from 66 to 500 kV were investigated under a constant test voltage of 50 Hz/7 kV (the 66 kV rating cable is from UK, the others from China). It was found that the characteristics of electrical trees in the inner region of 66 kV cable insulation differed considerably from those in the outer region under the same test conditions; however, no significant differences appeared in the 110 kV rating cable and above. The initiation time of electrical trees in both the inner and the outer regions of the 66 kV cable is much shorter than that in higher voltage rating cables; in addition the growth rate of electrical trees in the 66 kV cable is much larger than that in the higher voltage rating cables. By using x-ray diffraction, differential scanning calorimetry and thermogravimetry methods, it was revealed that besides the extrusion process, the molecular weight of base polymer material and its distribution are the prime factors deciding the crystallization state. The crystallization state and the impurity content are responsible for the resistance to electrical trees. Furthermore, it was proposed that big spherulites will cooperate with high impurity content in enhancing the initiation and growth processes of electrical trees via the 'synergetic effect'. Finally, dense and small spherulites, high crystallinity, high purity level of base polymer material and super-clean production processes are desirable for higher voltage rating cables.

  5. Use of Mineral Insulated Cables in Metro Stations%矿物绝缘电缆在地铁车站应用分析

    Institute of Scientific and Technical Information of China (English)

    程强

    2012-01-01

    矿物绝缘电缆是一种无机材料电缆,抗材料老化优于有机绝缘电缆,很难引发火灾或传播火焰,不会放出烟雾和有害气体。矿物绝缘电缆使用寿命较长,载流量大,且可经受较大的冲击力。但矿物绝缘电缆存在施工难度较大,安装要求较高等缺点。对矿物绝缘电缆与普通塑胶绝缘电缆进行了经济技术比较,分析其在地铁车站应用的可行性。%The mineral insulated cable is the cable of an inorganic material, the anti-aging material is better than the organic insulated cables. It is fire and flame retarded, generating no smoke and hazardous gas. Mineral insulated cables have longer service life, with large current-carrying capacity, and it can withstand a greater impact. The laying for mineral insulated cable is difficult, and installation has higher requirements. Comparing the mineral insulated cables and plastic insulated cables, cost-effective studies and technical analysis are carried out. The feasibility of the application in the metro station is studied.

  6. Numerical Modeling of the Electric Field and the Potential Distributions in Heterogeneous Cavities inside XLPE Power Cable Insulation

    Directory of Open Access Journals (Sweden)

    KHOUILDI Emna

    2016-10-01

    Full Text Available The XLPE power cable is easily affected by heterogeneous cavities: air void cavity, vented and bow-tie water trees. In this paper, we present a numerical modeling of this cable. A number of simulations are realized in order to analyze the influence of heterogeneous cavities and the influence of their positions and sizes on the electric field distribution, the potential distribution and the degradation of the XLPE insulation. The models are implemented with the finite element method based on the software package COMSOL Multiphysics.

  7. Effect of moisture on the electrical performance of transition-joints for medium voltage paper-insulated cables; Elektrische Beeintraechtigung durch Feuchtigkeit an oelgetraenkten Isolierpapieren. Mittelspannungsuebergangsmuffen

    Energy Technology Data Exchange (ETDEWEB)

    Cardinaels, Jos [Nexans Network Solution, Erembodegem (Belgium). Produktentwicklung; Baesch, Manfred [Nexans Power Accessories Germany, Dortmund (Germany). Produkt- und Qualitaetsmanagement

    2009-06-15

    Paper-insulated cables are constructed with an impervious metallic outer jacket in order to protect them against ingress of moisture. On 'modern' transition-joints to XLPE-insulated cables, this metal barrier is interrupted, hence, a risk of moisture penetration exists. This text presents measurements of water-vapour permeability of used materials and discusses the results of ageing tests. (orig.)

  8. Influence of γ-irradiation and temperature on the mechanical properties of EPDM cable insulation

    Science.gov (United States)

    Šarac, T.; Quiévy, N.; Gusarov, A.; Konstantinović, M. J.

    2016-08-01

    The mechanical properties of EPDM polymers, degraded as a result of extensive thermal and radiochemical aging treatment, are studied. The focus is given to dose rate effects in polymer insulation materials extracted from industrial cables in use in Belgian nuclear power plants. All studied mechanical characteristics such as the ultimate tensile stress, the Young's modulus, and the total elongation (or elongation at break) are found to be strongly affected by the irradiation dose. The ultimate tensile stress and Young's modulus are clearly exhibiting the dose rate effect, which originated from oxidation mediated interplay of polymer cross-linking and chain scission processes. The change of crossover between these two processes is found to be gradual, without critical dose rate or temperature values. On the contrary, the total elongation is observed not to be sensitive neither to irradiation temperature nor to the dose rate. Both cross-linking and chain scission seem to affect the total elongation in a similar way by reducing the average polymers chain length. This idea is confirmed by the model which shows that all total elongation data as a function of irradiation time can be reproduced by varying a single parameter, the pre-exponential factor of the irradiation rate constant.

  9. Degradation mechanisms of cable insulation materials during radiation-thermal ageing in radiation environment

    Science.gov (United States)

    Seguchi, Tadao; Tamura, Kiyotoshi; Ohshima, Takeshi; Shimada, Akihiko; Kudoh, Hisaaki

    2011-02-01

    Radiation and thermal degradation of ethylene-propylene rubber (EPR) and crosslinked polyethylene (XLPE) as cable insulation materials were investigated by evaluating tensile properties, gel-fraction, and swelling ratio, as well as by the infrared (FTIR) analysis. The activation energy of thermal oxidative degradation changed over the range 100-120 °C for both EPR and XLPE. This may be attributed to the fact that the content of an antioxidant used as the stabilizer for polymers decreases by evaporation during thermal ageing at high temperatures. The analysis of antioxidant content and oxidative products in XLPE as a model sample showed that a small amount of antioxidant significantly reduced the extent of thermal oxidation, but was not effective for radiation induced oxidation. The changes in mechanical properties were well reflected by the degree of oxidation. A new model of polymer degradation mechanisms was proposed where the degradation does not take place by chain reaction via peroxy radical and hydro-peroxide. The role of the antioxidant in the polymer is the reduction of free radical formation in the initiation step in thermal oxidation, and it could not stop radical reactions for either radiation or thermal oxidation.

  10. Degradation mechanisms of cable insulation materials during radiation-thermal ageing in radiation environment

    Energy Technology Data Exchange (ETDEWEB)

    Seguchi, Tadao, E-mail: seguchi@aj.wakwak.co [Japan Atomic Energy Agency, Tokai 319-1195 (Japan); Tamura, Kiyotoshi; Ohshima, Takeshi; Shimada, Akihiko [Japan Atomic Energy Agency, Tokai 319-1195 (Japan); Kudoh, Hisaaki [University of Tokyo, Tokai 319-1195 (Japan)

    2011-02-15

    Radiation and thermal degradation of ethylene-propylene rubber (EPR) and crosslinked polyethylene (XLPE) as cable insulation materials were investigated by evaluating tensile properties, gel-fraction, and swelling ratio, as well as by the infrared (FTIR) analysis. The activation energy of thermal oxidative degradation changed over the range 100-120 {sup o}C for both EPR and XLPE. This may be attributed to the fact that the content of an antioxidant used as the stabilizer for polymers decreases by evaporation during thermal ageing at high temperatures. The analysis of antioxidant content and oxidative products in XLPE as a model sample showed that a small amount of antioxidant significantly reduced the extent of thermal oxidation, but was not effective for radiation induced oxidation. The changes in mechanical properties were well reflected by the degree of oxidation. A new model of polymer degradation mechanisms was proposed where the degradation does not take place by chain reaction via peroxy radical and hydro-peroxide. The role of the antioxidant in the polymer is the reduction of free radical formation in the initiation step in thermal oxidation, and it could not stop radical reactions for either radiation or thermal oxidation.

  11. Elucidation for Electro-chemical Degradation of Cross-linked Polyethylene Insulated Power Cable

    Science.gov (United States)

    Miyashita, Yoshitsugu

    The water treeing phenomenon has been recognized as an ultimate difficulty for long-term service life of cross-linked polyethylene (XLPE) insulated power cables. Elucidation of substantial mechanistic pathway of water treeing is quite important to suppress water treeing. Many factors which affect water treeing have been found, such as electrical stress, existence of water, temperature and mechanical stress, and somewhat complicated synergestic interaction between them has also been pointed out. These factors make water treeing very difficult to be understood. The author studied the role of water in this phenomenon. To obtain certain analogical evidence for water treeing, a series of experiments was conducted by employing, as substituents of water, several organic solvents which possess relatively high dielectric constant and dissimilar electrochemical behavior, respectively. Consequently, it was found that a new type of treeing in XLPE matrix could be generated by certain organic solvent without water, and such treeing became easier to incept and propagate when the solvent contained particular electrolyte. Further, it was also indicated that cation was more effective than anion on such solvent treeing. Water tree inception and propagation mechanism was discussed from these experimental results.

  12. Ceramic insulation for superconducting Nb{sub 3}Sn cables; Isolation ceramique pour cables supraconducteurs en Nb{sub 3}Sn

    Energy Technology Data Exchange (ETDEWEB)

    Puigsegur, A

    2005-01-15

    Nb{sub 3}Sn is the best superconductor candidate for the realization of high field magnets (>11 Tesla), its implementation remains delicate because of the great brittleness of material after the heat treatment necessary to the formation of Nb{sub 3}Sn compounds. The conventional insulation for Nb{sub 3}Sn requires to perform, after the heat treatment, a vacuum resin impregnation, which adds to the cost and raises failure risk. We have proposed an innovating ceramic insulation deposited directly on the unreacted conducting cable. After the heat treatment of the niobium tin, we obtain a coil having a mechanical cohesion, while maintaining a proper conductor positioning and a suitable electric insulation. After a rheological study, to characterize the impregnated suspension, we have shown that using this insulation in a coil manufacture process does not affect the electrical properties of the Nb{sub 3}Sn wires. A solenoid of small dimensions was tested with success in high external magnetic fields and has produced a magnetic field of 3.8 T under 740 A. (author)

  13. Semiannual report for the period October 1, 1978 to March 31, 1979 of work on: (1) superconducting power transmission system development; and (2) cable insulation development

    Energy Technology Data Exchange (ETDEWEB)

    1979-05-11

    The objective of the program is to develop an underground superconducting power transmission system which is economical and technically attractive to the utility industry. The system would be capable of carrying very large blocks of electric power, thus enabling it to supplant overhead lines in urban and suburban areas and regions of natural beauty. The program consisted initially of work in the laboratory to develop suitable materials, cryostats, and cable concepts. The materials work covers the development and testing of suitable superconductors, and dielectric insulation. The laboratory work has now been extended to an outside test facility which represents an intermediate step between the laboratory scale and a full-scale system. The facility will allow cables several hundred feet long to be tested under realistic conditions. In addition, the refrigerator has been designed for optimum service for utility applications. Progress in cable conductor and cable insulation development and in the engineering facilities for fabricating and testing the superconducting cables is reported. (LCL)

  14. Finite Element Modeling in 3D of the Impact of Superfluid Helium Filled Micro-channels on the Heat Transfer through LHC Type Cable Insulation

    CERN Document Server

    Bielert, E; ten Kate, H

    2012-01-01

    For a future luminosity upgrade of CERN’s Large Hadron Collider, a drastically improved heat removal in the inner triplet quadrupole magnets is required. One of the necessary improvements involves the cable insulation. A porous all-polyimide insulation scheme has been proposed recently. Essentially the insulation features a network of micro channels filled with superfluid helium that significantly increases the heat transfer through the insulation layer. A three dimensional Finite Element model required to simulate and study the enhanced heat transfer through the micro channels is presented here. The thermal coupling between heated cable and helium as well as the heat flux through the micro-channels are investigated. The model is validated by comparison of results with published measured data. Finally a sensitivity analysis is performed concerning the stability of the cables in magnet windings.

  15. Aging Evaluation for NPP Cable with XLPE Insulation by using Oxidation Induction Time Measurement Test

    Energy Technology Data Exchange (ETDEWEB)

    Jang, Kyung Nam [Research Institute of Korea Electric Power Corporation, Daejeon (Korea, Republic of)

    2009-05-15

    There are a lot of cables in the nuclear power plant. The cables, especially inside containment, are exposed in the harsh environment. Those cables may be aged more rapidly due to the high temperature and radiation, and the life time of them may be shorter. If the life time of the cables in the harsh environment is expired due to the rapid aging, those cables should be replaced immediately. For the replacement in the appropriate time before the end of life time, we should perform the frequent condition monitoring of the cable. Among the many method of condition monitoring, we used the oxidation induction time (OIT) measurement test method because the polymer aged by means of chemical reactions with oxygen. Especially, in this paper, we analyze the OIT value affected by thermal and radiation aging.

  16. 型式试验对挤塑绝缘高压直流电缆老化状态的影响研究%Influence of Type Test on Ageing Status of Extruded Cross-linked Polyethylene (XLPE) High Voltage Direct Current (HVDC) Cables

    Institute of Scientific and Technical Information of China (English)

    李淑琦; 朱永华; 罗兵; 廖一凡; 吴建东; 尹毅

    2015-01-01

    The influence of type test on cable insulation was analyzed by testing the space charge, iso-thermal relaxation current (IRC), and thermal properties of 200 kV home-made extruded XLPE HVDC cables. The degassed samples from the central section of main insulation had distinct heteropolar space charge distribution on the surface before and after type test, while the accumulation of space charge changed little, and the status factor, enthalpy, and crosslinking degree had little change also, which indicated that the influence of type test on the ageing degree of central insulation of cables was small. After degassing treatment, the accumulation of heteropolar space charge and the average charge density reduced significantly, this indicated that the space charge behavior was influenced by crosslinking byprod-ucts. The test results of IRC and DSC show good relevance and can effectively reflect the change of age-ing status, which means that they are suitable to evaluate the insulation status of extruded XLPE HVDC cables.%通过对国内自行研制的200 kV挤塑绝缘交联聚乙烯电缆的空间电荷、松弛电流和热性能进行测试,分析了型式试验对电缆绝缘的影响。型式试验前后,主绝缘中部切片试样在表面区域均存在明显的异极性空间电荷分布,且电荷积累量变化不大,状态因子、熔融热焓、结晶热焓和交联度变化亦不明显,表明型式试验对电缆中部绝缘的老化程度影响较小。切片脱气处理后,试样表面区域的异极性空间电荷积累和短路时空间电荷平均单位体积密度显著降低,表明空间电荷行为受制造过程中残留的交联副产物影响很大。空间电荷、等温松弛电流和差示扫描量热的测试结果的关联性较好,均能有效反映老化状态的变化,可用于挤塑绝缘直流电缆的绝缘状态评估。

  17. Design of a termination for a high temperature superconduction power cable

    DEFF Research Database (Denmark)

    Rasmussen, Carsten; Kühle (fratrådt), Anders Van Der Aa; Tønnesen, Ole

    1999-01-01

    In this presentation we discuss the design of a termination for a high temperature superconducting power cable with the following design: A cable conductor consisting of superconducting tapes wound onto a tight flexible tube (former) is placed inside a thermally insulating jacet (cryostat......). This assembly is electrically insulated with an extruded polymer dielectric kept at room temperature. Cooling is provided by a flow of liquid nitrogen inside the former. The purpose of the termination is to connect the superconducting cable conductor at cryogenic temperature to the existing power grid at room...... temperature and to connect an external cooling machine at ground potential to the cable. Some of the aspects that have to be considered include the thermal insulation of the termination, the transition from superconducting tapes to a normal conductor, the current lead carrying current between high and low...

  18. 矿物绝缘预分支电缆施工要点%Key Construction Points of Mineral Insulated Prefabricated Branch Cable

    Institute of Scientific and Technical Information of China (English)

    苏矿

    2016-01-01

    针对矿物绝缘预分支电缆电气施工中的防潮难点,结合在施工中遇到的问题,从施工工艺及施工原理着手,总结矿物绝缘预分支电缆施工中的电缆敷设、电缆中间接头、终端头制作和临时密封等工序的注意事项,以及剥除铜护层、核对电缆相序、终端头的制作、电缆中间接头制作等施工要点。%Regarding the moisture proof difficulties encountered in the electrical construction of mineral insulated prefabricated branch cable, as well as the problems during construction process, this article summaries the precautions during cable installation, cable intermediate head and terminal head production, temporary seal process etc. of mineral insulated prefabricated branch cable construction. Key construction points in mineral insulated prefabricated branch cable copper sheath removal, cable phase sequence check, terminal head production, and intermediate head production are also covered.

  19. Negative differential mobility for negative carriers as revealed by space charge measurements on crosslinked polyethylene insulated model cables

    Science.gov (United States)

    Teyssedre, G.; Vu, T. T. N.; Laurent, C.

    2015-12-01

    Among features observed in polyethylene materials under relatively high field, space charge packets, consisting in a pulse of net charge that remains in the form of a pulse as it crosses the insulation, are repeatedly observed but without complete theory explaining their formation and propagation. Positive charge packets are more often reported, and the models based on negative differential mobility(NDM) for the transport of holes could account for some charge packets phenomenology. Conversely, NDM for electrons transport has never been reported so far. The present contribution reports space charge measurements by pulsed electroacoustic method on miniature cables that are model of HVDC cables. The measurements were realized at room temperature or with a temperature gradient of 10 °C through the insulation under DC fields on the order 30-60 kV/mm. Space charge results reveal systematic occurrence of a negative front of charges generated at the inner electrode that moves toward the outer electrode at the beginning of the polarization step. It is observed that the transit time of the front of negative charge increases, and therefore the mobility decreases, with the applied voltage. Further, the estimated mobility, in the range 10-14-10-13 m2 V-1 s-1 for the present results, increases when the temperature increases for the same condition of applied voltage. The features substantiate the hypothesis of negative differential mobility used for modelling space charge packets.

  20. Application of Laser Technology in Cutting Cable Insulating Materials%激光在电缆绝缘材料切割中的应用

    Institute of Scientific and Technical Information of China (English)

    蔡斌; 王忠峰; 徐婕

    2013-01-01

    The principle and characteristics of laser in cutting cable insulating materials are introduced. And comparison is done between laser cutting and traditional cutting and striping process for cable insulating materials. Taking the production of Z71 cable assembly as example, by using laser cutting technology, not only the qualification rate and work efficiency are increased, the producing cost is reduced, but also the hidden troubles of the damage of inner and outer conductor during cutting cable insulating materials are eliminated thoroughly. Thus the quality of cable assembly is improved fully.%介绍了激光切割电缆绝缘材料的工作原理和特点,并与传统的电缆绝缘材料切剥工艺进行了对比.以Z71电缆组件生产为例,采用激光切割技术后,不但提高了电缆组件的合格率和工作效率,降低了生产成本,还彻底消除了电缆绝缘材料切割时对内外导体的损伤隐患,全面提高了电缆组件的质量.

  1. Life performance of an EPR-insulated power cable exposed in service beyond 3 MGy in high-level radiation area

    Science.gov (United States)

    Grüb, R.; Langeset, B.; Maier, P.; Schönbacher, H.

    1983-09-01

    Mechanical and electrical test results are reported for a power cable that has been installed for three and a half years in a high-level radiation area at the European Organization for Nuclear Research (CERN). The degradation of selected mechanical properties as a function of absorbed dose is compared with results of a short-term irradiation in a nuclear reactor. The tensile test specimens have been taken from the ethylene propylene rubber insulation and the polyvinyl chloride sheath material of the cable after exposure in service. For the measurement of breakdown voltage, short portions of insulated cable have been used. The aim of this work was to verify that the combined functional and environmental stress factors did not lead to more damage of the cable than was expected from the value of absorbed dose, and eventually to predict more precisely the service life of similar cables. The ratios of doses after service and short-term irradiation at 50% reduction of elongation at break were about 0.5 for the insulation and 1.0 for the sheath material at a dose of about 1 MGy. However, the breakdown voltage did not show any significant variation in the dose range covered up to 3.6 MGy. Therefore, a safe lower dose limit may readily be derived from accelerated tests, but the margin until failure in service remains to be determined.

  2. Effect of Insulation Properties on the Field Grading of Solid Dielectric DC Cable

    DEFF Research Database (Denmark)

    Boggs, S.; Damon, Dwight Hill; Hjerrild, Jesper;

    2001-01-01

    field, however. Based on measured material properties, we demonstrate the effect of such dependencies on the field grading of dc cable for the range of measured material properties and provide an analytical approximation for computing the field of resistively graded dielectrics, including the effect......The development of solid dielectric dc transmission class cable is a priority throughout much of the world, to avoid risks associated with placing hydrocarbon fluids in underwater environments. The conductivity of polymeric solid dielectrics tends to be a strong function of temperature and electric...

  3. Negative differential mobility for negative carriers as revealed by space charge measurements on crosslinked polyethylene insulated model cables

    Energy Technology Data Exchange (ETDEWEB)

    Teyssedre, G., E-mail: gilbert.teyssedre@laplace.univ-tlse.fr; Laurent, C. [Université de Toulouse, UPS, INPT, LAPLACE (Laboratoire Plasma et Conversion d' Energie), 118 route de Narbonne, F-31062 Toulouse cedex 9 (France); CNRS, LAPLACE, F-31062 Toulouse (France); Vu, T. T. N. [Université de Toulouse, UPS, INPT, LAPLACE (Laboratoire Plasma et Conversion d' Energie), 118 route de Narbonne, F-31062 Toulouse cedex 9 (France); Electric Power University, 235 Hoang Quoc Viet, 10000 Hanoi (Viet Nam)

    2015-12-21

    Among features observed in polyethylene materials under relatively high field, space charge packets, consisting in a pulse of net charge that remains in the form of a pulse as it crosses the insulation, are repeatedly observed but without complete theory explaining their formation and propagation. Positive charge packets are more often reported, and the models based on negative differential mobility(NDM) for the transport of holes could account for some charge packets phenomenology. Conversely, NDM for electrons transport has never been reported so far. The present contribution reports space charge measurements by pulsed electroacoustic method on miniature cables that are model of HVDC cables. The measurements were realized at room temperature or with a temperature gradient of 10 °C through the insulation under DC fields on the order 30–60 kV/mm. Space charge results reveal systematic occurrence of a negative front of charges generated at the inner electrode that moves toward the outer electrode at the beginning of the polarization step. It is observed that the transit time of the front of negative charge increases, and therefore the mobility decreases, with the applied voltage. Further, the estimated mobility, in the range 10{sup −14}–10{sup −13} m{sup 2} V{sup −1} s{sup −1} for the present results, increases when the temperature increases for the same condition of applied voltage. The features substantiate the hypothesis of negative differential mobility used for modelling space charge packets.

  4. Ground Return Current Behaviour in High Voltage Alternating Current Insulated Cables

    Directory of Open Access Journals (Sweden)

    Roberto Benato

    2014-12-01

    Full Text Available The knowledge of ground return current in fault occurrence plays a key role in the dimensioning of the earthing grid of substations and of cable sealing end compounds, in the computation of rise of earth potential at substation sites and in electromagnetic interference (EMI on neighbouring parallel metallic conductors (pipes, handrails, etc.. Moreover, the ground return current evaluation is also important in steady-state regime since this stray current can be responsible for EMI and also for alternating current (AC corrosion. In fault situations and under some assumptions, the ground return current value at a substation site can be computed by means of k-factors. The paper shows that these simplified and approximated approaches have a lot of limitations and only multiconductor analysis can show the ground return current behaviour along the cable (not only the two end values both in steady-state regime and in short circuit occurrence (e.g., phase-to-ground and phase-to-phase-to-ground. Multiconductor cell analysis (MCA considers the cable system in its real asymmetry without simplified and approximated hypotheses. The sensitivity of ground return current on circuit parameters (cross-bonding box resistances, substation earthing resistances, soil resistivity is presented in the paper.

  5. Analysis on Key Technology of Quality Control of Insulated Conductor in XLPE Cable%交联电缆绝缘线芯质量控制关键技术分析

    Institute of Scientific and Technical Information of China (English)

    金金元; 王伟兴; 罗照辉; 刘振球

    2013-01-01

    By analysis on technology control process,such as insulated conductor in XLPE cable,insulated materials and XLPE cable production process,this article gives an introduction to the key points on the quality control of XLPE cable insulated conductor.%本文通过对交联电缆绝缘线芯导体、绝缘料、交联生产过程等技术控制过程进行分析,阐述了交联电缆绝缘线芯质量控制的要点。

  6. Corrosion Assessment of Cable Conductor in Insulation Repair Technique for XLPE Cables%XLPE电缆绝缘修复技术中缆芯导体的腐蚀性评估

    Institute of Scientific and Technical Information of China (English)

    刘曦; 陶霰韬; 周凯; 杨琳; 赵威

    2013-01-01

      分别对铜芯和铝芯交联聚乙烯制造针刺缺陷并高频高压加速老化,然后对老化后的电缆试样进行硅氧烷注入式修复,并对铜芯和铝芯电缆的缆芯进行了电镜扫描(SEM)和X射线光电子能谱(XPS)分析,研究硅氧烷注入式修复技术的修复效果及其对缆芯导体的腐蚀性。结果表明:修复后的电缆的绝缘性能显著提高,其介质损耗角正切值(tanδ)与工频击穿电压均优于未修复老化电缆,且与新电缆基本相同。铝芯电缆的缆芯明显被腐蚀,而铜芯电缆不受影响。%A needle defect was made in the copper core and aluminum core XLPE cables, and the ca-bles were accelerated aging under high frequency and high voltage. Then the aging cables were repaired by injecting siloxane, and the repair effects and corrosion of the siloxane on conductor were studied by scanning electron microscope(SEM) and X-ray photoelectron spectroscopy(XPS). The results show that the insulation properties of the repaired cables are improved significantly. The tanδ and breakdown voltage of the repaired cables are better than that of the aged cables, which are almost equal to the new cables. The aluminum core of the repaired cables is badly corroded, while the copper core is unaffected.

  7. Use of cable and magnet insulators in a nuclear radiation field

    CERN Document Server

    Schönbacher, Helmut

    1978-01-01

    The use of commercial insulating materials in the construction of the CERN complex, Geneva, is considered. The results presented were obtained principally by testing in a reactor, but also on the basis of experience acquired with the CERN accelerators, and relate to working temperatures in thr 20-50 degree C range and maximum integrated dosages of 100 megagrays. (11 refs).

  8. 7 CFR 1755.890 - RUS specification for filled telephone cables with expanded insulation.

    Science.gov (United States)

    2010-01-01

    ... be either totally expanded or expanded with a solid skin coating. (ii) The insulated conductors are... screen tape must be tested for dielectric strength by completely removing the protective coating from one... and Materials (ASTM) B 694-86, with a cladding ratio of 16/68/16. (A) The electrical conductivity of...

  9. Study on Insulation Enhancement Technology of XLPE Cable%一种针对XLPE电缆的绝缘增强技术研究

    Institute of Scientific and Technical Information of China (English)

    苑吉河; 张曦; 张瑞冬; 周凯; 陈讴; 黄明

    2016-01-01

    In order to eliminate the potential defects in the installation and production of cables, the sili-cone rejuvenation liquid was injected into the cross-linked polyethylene (XLPE) new cables (pre-repaired), and the effect of pre-repair on the insulation structure and insulating properties of the new cables was investigated. At first, the rejuvenation liquid was injected into the cable samples by pressure injection equipment, and the breakdown voltage and temperature of the new cable samples and the pre-repair sam-ples were measured. Then the two samples were placed for three months, and their breakdown voltage was measured again. The results indicate that the breakdown voltage of the pre-repair cable samples is higher than that of the new samples, and there is little difference between the temperatures of the two samples, indicating that the influence of silicone rejuvenation liquid on the thermal effects is not obvious in the breakdown test. The breakdown voltage of the pre-repair cable samples after placed for three months is lower than that of the pre-repair cable samples, but it is still higher than that of the new cable samples. According to the capacitance model of insulation layer and principle of dielectrophoresis, the cable insulation is no longer a homogeneous medium after injecting rejuvenation liquid, it turns into a grated insulation composite medium, so the insulating properties of the XLPE cable is improved.%为了解决电缆安装或制造过程中的潜在缺陷,通过向尚未投入运行的新电缆预先注入有机硅修复液(即预修复),研究修复液注入后对电缆的绝缘结构及电气性能的影响.首先通过压力注入装置将有机硅修复液注入到电缆样本中,测量新电缆样本和预修复液样本的工频击穿电压,记录两种样本在击穿过程中的温升情况.然后将两种样本放置3个月,再次测量样本的工频击穿电压并进行对比.结果表明:预修复电缆样本的工频击穿电压

  10. Superconductor cable

    Science.gov (United States)

    Allais, Arnaud; Schmidt, Frank (Langenhagen, DE

    2009-12-15

    A superconductor cable includes a superconductive cable core (1) and a cryostat (2) enclosing the same. The cable core (1) has a superconductive conductor (3), an insulation (4) surrounding the same and a shielding (5) surrounding the insulation (4). A layer (3b) of a dielectric or semiconducting material is applied to a central element (3a) formed from a normally conducting material as a strand or tube and a layer (3c) of at least one wire or strip of superconductive material is placed helically on top. The central element (3a) and the layer (3c) are connected to each other in an electrically conducting manner at the ends of the cable core (1).

  11. Selected developments in laser wire stripping. [cutting insulation from aerospace-type wires and cables

    Science.gov (United States)

    1977-01-01

    The operation of mechanical and thermal strippers and the early development of laser wire strippers are reviewed. NASA sponsored development of laser wire stripping for space shuttle includes bench-type strippers as well as an advanced portable hand-held stripper which incorporates a miniaturized carbon dioxide laser and a rotating optics unit with a gas-jet assist and debris exhaust. Drives and controls girdle the wire and slit the remaining slug without manual assistance. This unit can strip wire sizes 26 through 12 gage. A larger-capacity hand-held unit for wire sizes through 1/0 gage was built using a neodynium-doped yttrium aluminum garnet (Nd:YAG) laser. The hand-held units have a flexible umbilical cable to an accompanying cart that carries the power supply, gas supply, cooling unit, and the controls.

  12. Development of a method for evaluation of the life curve of the HV and EHV cable polymeric insulation: The first results and fields of application

    Science.gov (United States)

    Peshkov, I. B.; Ovsienko, V. L.; Shuvalov, M. Yu.

    2015-12-01

    A test procedure and an experimental setup are presented that enable derivation of the "life curve," i.e., the electrical tree induction period vs. applied voltage dependence for the low-density crosslinked polyethylene insulation. The developed equipment allows testing samples of materials both made in a laboratory and cut out from commercially manufactured cables at room temperature and at long-term permissible and overload temperatures. The fact of the electrical tree inception is established by light microscopy directly during simultaneous high-voltage test of ten samples. The optical system and the applied micromanipulation technique provide spatial resolution of approximately 1.5 μm, high-precision delivery of the microelectrode to the area of interest inside the sample, a permanent and reliable contact between the microelectrode and the material, and preservation of the residual mechanical stress field. The obtained results can be applied to development of new high-voltage cables with polymer insulation. The derived "life curve" enabled—using the corresponding mathematical model—calculation of the electric insulation thickness, which reaches 19-20 mm for the 220-kV cables.

  13. Study on predicting cable insulation failure in case of heat radiation%热辐射作用下电缆绝缘失效时间预测

    Institute of Scientific and Technical Information of China (English)

    舒中俊; 王霁; 孙青辉; 张克俭

    2011-01-01

    电缆绝缘材料在火灾条件下的失效时间对电缆工程的设计和施工是个非常重要的参数,这些数据多以试验的方式获得.以试验结果为基础,在假设的前提下,运用传热学理论建立了电缆在热辐射作用下其内部的温度分布模型,并应用MATLAB软件中的pdepe函数求得了模型的数值解,即电缆内部各点温度随时间的变化关系,据此获得电缆绝缘失效时间.以ZR-VV电缆为研究对象,应用该模型计算得出了热通量分别为3 kW/m2、5 kW/m2、7 kW/m2、24 kW/m2、40 kW/m2和56 kW/m2时,电缆内部的温度分布及火效时间.计算值与试验结果吻合较好,说明使用所建立的模型可以近似预测电缆在不同热辐射条件下的绝缘失效时间.%The present paper is inclined to introduce our study results on how to predict the cable insulation failure in case of heat radiation because we believe that it is of fatal importance for the construction workers to know how to prevent such disastrous accidents. It is just for such reasons that we have been attaching particular attention to the study of the vulnerability of electrical cables when exposed to fire, trying to gain the precise data leading to the failure. For this study goal, we have conducted a series of experiments based on reviewing technical literature concerning the problem. However, the critical insulation failure moment or instant, at which the failure is supposed to take place can only be predicted by establishing a temperature model of cable in different fire conditions. Therefore, this paper has proposed a model of internal temperature distribution of the cable when it is exposed to external radiation sources based on the results of our cable insulation failure experiments, the reasonable hypotheses and heat transfer theories concerned. And in turn we have established the differential equation by using the MATLAB function of pdepe, and found the time-temperature relation at each point of

  14. An examination of the potential for nano-composites in the formulation of HV cable insulation

    Science.gov (United States)

    Roy, Mihir

    In order to find an appropriate cable dielectric material, nanodielectrics consisting of silica particles in cross-linked polyethylene (XLPE) have been formulated using melt-mixing. Various types of chemical modifications were provided to the surface of the nanoparticles in order to understand the mechanism of the particle-polymer interface and to tailor the properties of overall composites. The particulates and the composites formulated have been characterized utilizing several techniques such as electron paramagnetic resonance, Fourier transformed infra-red spectroscopy, x-ray photoelectron spectroscopy, nuclear magnetic resonance, and microscopy. These nanomaterials were examined for their electrical attributes, and substantial improvement in electrical voltage endurance was demonstrated. In addition significant improvements in electric strength were measured and other physical properties important to the processing and application of cable dielectrics were not sacrificed. It was established that the interfacial charge build-up that is a common feature of micro-filled material is absent in nanodielectrics, and there was also a reduction in over all permittivity of the nanocomposite below that of the base resin. To understand the mechanism involved in the improvement in the dielectric properties, the chemistry and physics of the particle-polymer interface was crucial. Therefore, some electrical characterizations of the composite materials were performed to find the trap-site separation, trap depth, mobility of the charge carriers, threshold field for internal charge accumulations etc. The chain scission mechanism proposed by Artbauer via free volume theory was extended to the interfacial defects in the composites; the size of such defects being significantly different for the nano- versus micro-composites. The defects resulted in a microcomposite with very low electric strength, and mitigation of the defects via chemical linkage between particle and polymer

  15. Conductive cable fibers with insulating surface prepared by co-axial electrospinning of multi-walled nanotubes and cellulose

    Science.gov (United States)

    Miyauchi, Minoru; Miao, Jianjun; Simmons, Trevor J.; Lee, Jong-Won; Doherty, Thomas V.; Dordick, Jonathan S.; Linhardt, Robert J.

    2010-01-01

    A core-sheath of multi-walled carbon nanotube (MWNT)-cellulose fibers of diameters from several hundreds nm to several µm were prepared by co-axial electrospinning from a non-valatile, non-flammable ionic liquid (IL) solvent, 1-methyl-3-methylimidazolium acetate ([EMIM][Ac]). MWNTs were dispersed in IL to form a gel solution. This gel core solution was electrospun surrounded by a sheath solution of cellulose disolved in the same IL. Electrospun fibers were collected in a coagulation bath containing ethanol-water to completely remove the IL and dried to form a core-sheath MWNT-cellulose fibers having a cable structure with a conductive core and insulating sheath. Enzymatic treatment of a portion of a mat of these fibers with cellulase selectively removed the cellulose sheath exposing the MWNT core for connection to an electrode. These MWNT-cellulose fiber mats demonstrated excellent conductivity due to a conductive pathway of bundleled MWNTs. Fiber mat conductivity increased with increasing ratio of MWNT in the fibers with a maximum conductivity of 10.7 S/m obtained at 45 wt% MWNT loading. PMID:20690644

  16. XLPE电缆绝缘水树枝非线性特性建模仿真分析%Nonlinear behavior analysis of water tree on XLPE insulated power cables

    Institute of Scientific and Technical Information of China (English)

    熊博

    2012-01-01

    Water tree degradation phenomenon constitutes a serious problem in XLPE insulated power cables. The water tree results in U-I non-linear characteristics of XLPE cables. According the characteristics, the leak current of XLPE insulated power cables were tested. The Particle swarm optimization algorithm was applied to optimize the XLPE insulated power cables model parameters. The correctness of the model has been verified. This paper also built an equivalent circuit model of XLPE cables with water tree, and the harmonic currents were simulated. Result showed that the leak current of the water tree XLPE cable existed obvious distortion; it can be used to determine the degree of XLPE cable insulation degradation.%水树枝老化是影响交联聚乙烯(XLPE)电力电缆绝缘性能最主要原因,水树枝导致XLPE电缆U-I呈现非线性关系.依据该非线性特性,对XLPE电缆漏导电流进行试验分析,采用粒子群算法对XLPE电缆模型参数进行寻优,建立含水树枝的XLPE电缆等效电路模型;并对漏导电流进行谐波分析,根据漏导电流畸变程度判断XLPE电缆水树老化程度.

  17. Experimental and analytical study of the DC breakdown characteristics of polypropylene laminated paper with a butt gap condition considering the insulation design of superconducting cable

    Science.gov (United States)

    Seo, In-jin; Choi, Won; Seong, Jae-gyu; Lee, Bang-wook; Koo, Ja-yoon

    2014-08-01

    It has been reported that the insulation design under DC stress is considered as one of the critical factors in determining the performance of high-voltage direct current (HVDC) superconducting cable. Therefore, it is fundamentally necessary to investigate the DC breakdown characteristics of the composite insulation system consisting of liquid nitrogen (LN2)/polypropylene-laminated-paper (PPLP). In particular, the insulation characteristics under DC polarity reversal condition should be verified to understand the polarity effect of the DC voltage considering the unexpected incidents taking place at line-commutated-converters (LCC) under service at a DC power grid. In this study, to examine the variation of DC electric field strength, the step voltage and polarity reversal breakdown tests are performed under DC stress. Also, we investigate the electric field distributions in a butt gap of the LN2/PPLP condition considering the DC polarity reversal by using simulation software.

  18. Insulator

    Energy Technology Data Exchange (ETDEWEB)

    Nakajima, Isao; Ikami, Toshiichi.

    1990-09-17

    The insulating properties of transmission line insulators are reduced when the insulator becomes contaminated. Such contamination is promoted by the adherence of rainwater including dusts and/or absorbing of dusts and gas when the insulated surface is wetted with rainwater. It is known to treat insulators with water repellent compounds to avoid this problem, but known treatments have certain disadvantages such as loss of water repellency in a short time. An object of this invention is to overcome these disadvantages and to provide an insulator having a high usefulness and excellent water repellency which can be easily treated and maintained over a long period of time. It has been found that if a glass layer itself forming the surface of the insulator has water repellent properties, the water repellency of the insulator surface is not lost. According to the invention, the glassy surface is treated with silane or silazane to provide a surface layer of the proper water repellency. The insulator surface may be preferably treated in such a manner that the insulator is immersed in a bath of silane or silazane. Experiments are described to illustrate the performance of insulators treated according to the invention in comparison to non-treated insulators. 1 fig., 1 tab.

  19. Study on Space Charge Characteristic of New XLPE Insulation Material for HVDC Cable%新型XLPE高压直流电缆绝缘料的空间电荷特性研究

    Institute of Scientific and Technical Information of China (English)

    陈曦; 吴锴

    2015-01-01

    The temperature gradient effect during operation of HVDC cables will lead to field distortion greatly of the outer insulation layer, which would lead to the electric strength and lifetime of cable insu-lation decrease. Based on the polyethylene nanocomposites, a new HVDC cable insulation material was prepared by adding crosslinking agent and antioxygen, and its mechanical properties and electrical proper-ties were tested, and then its space charge accumulation and field distortion characteristic were compared with foreign XLPE HVDC cable insulation material. The results show that the properties of the new HVDC cable insulation material are superior to the foreign cable material, and the new HVDC cable insu-lation material is expected to be used in the production of HVDC cables.%高压直流电缆运行中的温度梯度效应导致电缆外绝缘层场强严重畸变,降低了绝缘的电气强度和使用寿命。在聚乙烯纳米复合材料的基础上,添加适量的交联剂、抗氧剂等制备了新型高压直流交联聚乙烯料,对其力学性能和电性能进行测试,并将其与国外主流XLPE直流电缆绝缘料的空间电荷积聚与场强畸变特性进行对比分析。结果表明:新型高压直流交联聚乙烯电缆料的性能优于国外主流XLPE直流电缆绝缘料,有望用于国产高压直流电缆。

  20. 用电磁波速诊断XLPE电缆绝缘%Diagnosis of XLPE Cable Insulation Using Velocity of Electromagnetic Wave

    Institute of Scientific and Technical Information of China (English)

    王黎明; 侯经洲; 陈昌龙

    2011-01-01

    XLPE电缆绝缘诊断的研究对于掌握电缆的绝缘老化状态,保证电力传输系统的安全可靠运行有着十分重要的意义。针对工程实际中大规模应用的诊断方法不多见的现状,提出了一种XLPE电缆状态检测的新方法,即用电磁波在一段XLPE电缆中的传播速度作为诊断这段电缆是否发生老化的依据。在阐明了该方法的原理和理论依据后介绍了所搭建的实验平台,按照提出的方法对两条不同绝缘老化状态的XLPE电缆进行了诊断测量并在测量数据的处理中确定了标定电磁波往返时间的有效方法。结果表明,用电磁波速进行XLPE电缆绝缘诊断可以很好的表征出两条XLPE电缆是否已发生了老化。最后,对测得的波形进行了说明,并通过将电磁波速的测量值与理论值进行对比,表明这一方法具有较高的准确性和可靠性,从而为XLPE电缆绝缘诊断提供新的思路。%The research on diagnosis of XLPE power cable insulation is of a great importance for realizing the cable insulation aging status and ensuring the power transmission system in safe and reliable operation.Therefore,we put forward a new method,using electromagnetic wave propagation velocity in an XLPE cable as the criterion of whether the aging happens in the cable,set out the principles of the method and theoretical basis,and built a test platform.In accordance with the method proposed,we measured two different levels of water tree aged XLPE cables.During the measurement data processing,we also researched how to get the round-trip time effectively.The result indicates that using electromagnetic wave speed for diagnosis of XLPE cable insulation can reflect the insulation status of the two XLPE cables primly.Comparison of the different results suggests that this method is accurate and reliable,so as to provide new ideas for diagnosis of XLPE cable insulation.

  1. Intelligent Extruder

    Energy Technology Data Exchange (ETDEWEB)

    AlperEker; Mark Giammattia; Paul Houpt; Aditya Kumar; Oscar Montero; Minesh Shah; Norberto Silvi; Timothy Cribbs

    2003-04-24

    ''Intelligent Extruder'' described in this report is a software system and associated support services for monitoring and control of compounding extruders to improve material quality, reduce waste and energy use, with minimal addition of new sensors or changes to the factory floor system components. Emphasis is on process improvements to the mixing, melting and de-volatilization of base resins, fillers, pigments, fire retardants and other additives in the :finishing'' stage of high value added engineering polymer materials. While GE Plastics materials were used for experimental studies throughout the program, the concepts and principles are broadly applicable to other manufacturers materials. The project involved a joint collaboration among GE Global Research, GE Industrial Systems and Coperion Werner & Pleiderer, USA, a major manufacturer of compounding equipment. Scope of the program included development of a algorithms for monitoring process material viscosity without rheological sensors or generating waste streams, a novel detection scheme for rapid detection of process upsets and an adaptive feedback control system to compensate for process upsets where at line adjustments are feasible. Software algorithms were implemented and tested on a laboratory scale extruder (50 lb/hr) at GE Global Research and data from a production scale system (2000 lb/hr) at GE Plastics was used to validate the monitoring and detection software. Although not evaluated experimentally, a new concept for extruder process monitoring through estimation of high frequency drive torque without strain gauges is developed and demonstrated in simulation. A plan to commercialize the software system is outlined, but commercialization has not been completed.

  2. Deduction of Steady-State Cable Quench Limits for Various Electrical Insulation Schemes with Application to LHC and HL-LHC Magnets

    CERN Document Server

    Granieri, P

    2014-01-01

    Undesired quenches of superconducting magnets can be a limiting factor for the operation of the LHC accelerator, both for its forthcoming exploitation at full energy as well as for its future upgrades. An accurate knowledge of the quench limit, the maximum amount of heat deposit the magnets can withstand, is required to be able to prevent beam induced quenches. In this paper we provide an overview of the heat extraction through the multitude of cable insulation schemes used in particle accelerators in the past 20 years and foreseen for the coming years. Based on the relevant heat transfer measurements, we deduce steady-state cable quench limits both for the LHC Nb-Ti magnets and for the future HL-LHC Nb3Sn ones. We provide them for different operating conditions and different locations within the coil.

  3. PROBLEMS OF ECONOMIC CRITERIA APPLICATION TO CALCULATION AND DESIGN OF HIGH-VOLTAGE PLASTIC-INSULATED POWER CABLES

    Directory of Open Access Journals (Sweden)

    O.V. Golik

    2013-09-01

    Full Text Available Results of cable transmitting capacity calculation for voltage of up to 220 kV are analyzed. The work is devoted to creation of a current rating calculation technique for high-voltage cross-linked polyethylene cables.

  4. EXTRUDED POLYSTYRENE FOAM IN FLAT ROOFS

    Directory of Open Access Journals (Sweden)

    Zhukov Aleksey Dmitrievich

    2014-09-01

    Full Text Available In our article we prove the necessity of applying thermal insulation with low water absorption and resistance and preserving mechanical and thermophysical properties in corrosive environment in flat roofs, where there is always a danger of penetrating condensed moisture into the structure. As such material we offered extruded polystyrene foam - heat-insulating polymer material with uniformly distributed closed cells. The products are used in the form of slab insulation and special items - for forming slopes and venting.

  5. End moldings for cable dielectrics

    Energy Technology Data Exchange (ETDEWEB)

    Roose, L.D.

    1993-12-31

    End moldings for high-voltage cables are described wherein the dielectric insulator of the cable is heated and molded to conform to a desired shape. As a consequence, high quality substantially bubble- free cable connectors suitable for mating to premanufactured fittings are made. Disclosed are a method for making the cable connectors either in the field or in a factory, molds suitable for use with the method, and the molded cable connectors, themselves.

  6. Insulation design of the 110kV cold dielectric high temperature superconducting cable%110kV冷绝缘高温超导电缆本体绝缘设计

    Institute of Scientific and Technical Information of China (English)

    夏占军; 郭立杰; 诸嘉慧

    2011-01-01

    In this paper, we designed the insulation of the first 110kV cold dielectric (CD) cable using YBCO coated conductor in China. According to the structure of the CD HTS cable, dielectric properties of different insulation materials were analyzed , electric - field distribution of the HTS cable was calculated by the finite element numerical analysis method, the quantitative relationships, between insulation thickness and the partial discharge inception stress were studied based on the theoretical model. Finally, a design proposal about the insulation materials and its thickness for of the 110kV CD HTS cable was given.%对国内第一根基于YBCO涂层导体的110kV冷绝缘高温超导(CD HTS)电缆本体绝缘进行了设计.根据冷绝缘HTS电缆的结构特点,通过分析不同绝缘材料的介电特性,应用电场有限元数值分析模型和理论模型,计算了超导电缆本体电场分布,研究了超导电缆主绝缘厚度与局部放电起始场强的定量化关系,最后给出了110kV冷绝缘HTS电缆主绝缘材料与厚度的设计方案.

  7. Semiannual report for the period April 1 to September 30, 1978 of work on: (1) superconducting power transmission system development; (2) cable insulation development. Power Transmission Project technical note No. 83

    Energy Technology Data Exchange (ETDEWEB)

    1978-11-07

    Progress in the development, fabrication and testing of superconductors for HVAC power transmission systems is reported. Information is included on the materials evaluation of superconducting alloys, production of tapes from these alloys, principally Nb/sub 3/Sn cable insulation requirements and development, and the cryogenic equipment used in this research program. (LCL)

  8. 氟聚合物绝缘和护套控制电缆的应用及发展趋势%Application and Development Trend of Insulated and Sheathed Control Cable of Fluorine Polymer

    Institute of Scientific and Technical Information of China (English)

    沈丽敏

    2015-01-01

    The emergence and development of the new insulation materials like fluoroplastics make the wire and cable get large development. Especially their characteristics of high temperature resistant, environment resistant promote the rapid development of modern military cables. This paper introduces the characteristics, application, technical requirements and development trend of insulated and sheathed control cable of fluorine polymer.%以含氟塑料为代表的新绝缘材料的出现和发展,让电线电缆的发展谱写了新的一页,尤其是它们的耐高温、耐环境特性促进了军品线缆的高速发展,本文介绍了氟聚合物绝缘和护套控制电缆的特点、应用、技术要求及发展趋势。

  9. The Danish Superconducting Cable Project

    DEFF Research Database (Denmark)

    Tønnesen, Ole

    1997-01-01

    The design and construction of a superconducting cable is described. The cable has a room temperature dielectric design with the cryostat placed inside the electrical insulation.BSCCO 2223 superconducting tapes wound in helix form around a former are used as the cable conductor. Results from...

  10. Influence of Moisture on the Electrical Properties of XLPE Insulation

    OpenAIRE

    Mecheri, Yacine; Nedjar, Mohamed; Lamure, Alain; Aufray, Maëlenn; Drouet, Christophe

    2010-01-01

    International audience; During their operating service, insulated power cables can be exposed to wet environment. The presence of moisture in cables surroundings may affect the properties of the used insulation material for instance, XLPE widely employed in MV and HV power cables insulation and therefore the reliability of the insulated cables. In order to examine the influence of wet aging conditions on the performances of XLPE insulated cables,samples (plates moulded from granules HFDE 4201...

  11. XETFE电线电缆绝缘料的研究进展%Research Development of XETFE Wire and Cable Insulating Materials

    Institute of Scientific and Technical Information of China (English)

    史丛丛; 单永东

    2015-01-01

    Irradiation crosslinking ethylene-tetrafluoroethylene(XETFE) copolymer insulation wire and cable has advantages of high temperature resistance, radiation resistance, and light quality, and it is one of the most important type of aerospace cables. The formula, processing technology, standards, and research situation of XETFE were introduced, the technical difficulty was pointed out, and the prospect was proposed.%辐照交联乙烯-四氟乙烯(XETFE)共聚物绝缘电线电缆具有耐高温、耐辐射、质量轻等优点,是航空航天线缆的主要品种之一。通过介绍辐照交联乙烯-四氟乙烯(XETFE)绝缘料的配方研究、加工工艺、标准等国内外研究现状,指出了该绝缘料需要解决的技术难点,展望了其发展前景。

  12. 高压交联聚乙烯绝缘直流电力电缆工艺设计分析%Analysis of XLPE Insulation HVDC Cable Production Process Design

    Institute of Scientific and Technical Information of China (English)

    华建飞; 张治刚; 魏学志; 石春静; 杨丽伟

    2015-01-01

    对高压交联聚乙烯(XLPE)绝缘电力电缆的直流电场分布进行计算分析,并讨论直流与交流电场的差异。交流输电时,交联聚乙烯绝缘电缆的电场强度分布与电缆导体直径、绝缘厚度有直接关系,和介电常数成反比;而直流输电时,交联聚乙烯电缆的电场强度分布除了与电缆结构尺寸有关以外,还与绝缘材料电阻、电缆的负荷、温度有关,其电场强度分布在绝缘内表面与绝缘外表面之间相互变化。针对高压交/直流电缆电场分布的不同特点对比分析,在设计其生产工艺时也不尽相同,通过对交联聚乙烯绝缘直流电缆生产工艺的合理设计,保障直流电缆的长期稳定运行。%The HVDC Electric field distribution of high-pressure cross-linked polyethylene (XLPE) insulation cable was calculated and analyzed, and the difference between them was discussed. In AC transmission, electric ifeld intensity distribution is related to cable diameter and insulation thickness, and was inversely proportional to dielectric constant. While in DC transmission, except for the cable structure and size, electric ifeld intensity distribution was also related to insulation materials resistance, cable load and temperature, and it changes between the inner and outer surface of Insulator. Due to different electric ifeld distribution, AC/DC cables are different in design and production process. Through reasonable design process for XLPE insulation cable, AC/DC cables can be guaranteed long term stable operation.

  13. Ageing Condition Assessment of XLPE Cable Insulation Based on tanδ at 0.1 Hz%基于0.1 Hz下tanδ的XLPE电缆绝缘老化状态评估技术

    Institute of Scientific and Technical Information of China (English)

    刘英; 王林杰; 苏宇; 肖阳; 曹晓珑

    2016-01-01

    The detection technology of XLPE cable insulation has recieved more and more attention with the continuous development of power cable industry. It is an important and indispensable process of elec-trical equipment management at present for the effective assessment of cable insulation ageing condition. According to the IEEE test criteria about cable insulation diagnosis method at very low frequency (0.1 Hz), a new method was put forwarded to assess the ageing condition of XLPE insulation. The sam-ples were sliced from XLPE cable insulation layer, and the tanδ of the slice samples at 0.1 Hz were tested under different voltages, and then the voltage sensitivity was used to judge the ageing dgree of insulation. It is found that the change rule of tanδ with voltage can effectively reflect the difference of insulation ageing condition for the power cables after operating different years, and the tanδ of inner, middle, and outer insulation layers is different. The tanδ of inner and middel layers is normalized by set-ting the tanδ of outer layer as reference, and the relative value is used as a judgement basis of insula-tion ageing state. This method is an effective way for ageing condition assessment of XLPE cable insula-tions which are lack of original data.%随着电力电缆行业的持续发展,XLPE电缆绝缘检测技术受到越来越多的关注.对电缆绝缘老化状态的有效评估是当前电气设备管理一个十分重要和必不可少的过程.根据IEEE提出的有关电力电缆绝缘超低频(0.1 Hz)试验标准,提出一种对XLPE电缆绝缘分层取样,测量切片试样在0.1 Hz下的tanδ随外施电压的变化,以电压敏感度来判断绝缘老化程度的方法.通过测量不同运行年限的XLPE电缆绝缘,发现tanδ随外施电压的变化规律可以有效反映出不同运行时间绝缘老化状态的区别,绝缘内、中、外层的tanδ存在差异性.将老化电缆绝缘内层和中层的tanδ以外层tanδ测量值作

  14. Flammability of radiation cross-linked low density polyethylene as an insulating material for wire and cable

    Science.gov (United States)

    Basfar, A. A.

    2002-03-01

    Various formulations of low-density polyethylene blended with ethylene vinyl acetate were prepared to improve the flame retardancy for wire and cable applications. The prepared formulations were cross-linked by γ-rays to 50, 100, 150 and 200 kGy in the presence of trimethylolpropane triacrylate (TMPTA). The effect of thermal aging on mechanical properties of these formulations were investigated. In addition, the influence of various combinations of aluminum trihydroxide and zinc borate as flame retardant fillers on the flammability was explored. Limiting oxygen index (LOI) and average extent of burning were used to characterize the flammability of investigated formulations. An improved flame retardancy of low density polyethylene was achieved by various combinations of flame ratardant fillers and cross-linking by gamma radiation.

  15. 皱纹外导体泡沫PE绝缘RF同轴电缆的衰减特性%The Attenuation Characteristic of Corrugated Outer Conductor and Foamed PE Insulated RF Coaxial Cable

    Institute of Scientific and Technical Information of China (English)

    李庆和

    2011-01-01

    Attenuation is the most important transmission characteristic of RF coaxial cables. The corrugation depth of the outer conductor and the tg δ of foamed PE are the main factors affecting the attenuation of thc coaxial cable with corrugated outer conductor and foamed PE insulation. Shallow corrugation and the cleaning of dielectric material are the effective approaches to reduce the attenuation of such kind of coaxial cables.%衰减是射频(RF)同轴电缆最重要的传输特性.外导体皱纹深度及泡沫聚乙烯(PE)的介质损耗角正切tg δ是影响皱纹外导体泡沫PE绝缘同轴电缆衰减的主要因素.浅皱纹结构及净化介质材料是降低该电缆衰减值的有效途径.

  16. Cable Diagnostic Focused Initiative

    Energy Technology Data Exchange (ETDEWEB)

    Hartlein, R.A.; Hampton, R.N.

    2010-12-30

    This report summarizes an extensive effort made to understand how to effectively use the various diagnostic technologies to establish the condition of medium voltage underground cable circuits. These circuits make up an extensive portion of the electric delivery infrastructure in the United States. Much of this infrastructure is old and experiencing unacceptable failure rates. By deploying efficient diagnostic testing programs, electric utilities can replace or repair circuits that are about to fail, providing an optimal approach to improving electric system reliability. This is an intrinsically complex topic. Underground cable systems are not homogeneous. Cable circuits often contain multiple branches with different cable designs and a range of insulation materials. In addition, each insulation material ages differently as a function of time, temperature and operating environment. To complicate matters further, there are a wide variety of diagnostic technologies available for assessing the condition of cable circuits with a diversity of claims about the effectiveness of each approach. As a result, the benefits of deploying cable diagnostic testing programs have been difficult to establish, leading many utilities to avoid the their use altogether. This project was designed to help address these issues. The information provided is the result of a collaborative effort between Georgia Tech NEETRAC staff, Georgia Tech academic faculty, electric utility industry participants, as well as cable system diagnostic testing service providers and test equipment providers. Report topics include: •How cable systems age and fail, •The various technologies available for detecting potential failure sites, •The advantages and disadvantages of different diagnostic technologies, •Different approaches for utilities to employ cable system diagnostics. The primary deliverables of this project are this report, a Cable Diagnostic Handbook (a subset of this report) and an online

  17. High Voltage Cable Splicing and Cable Termination Techniques

    Science.gov (United States)

    1976-08-01

    solid dielectric insulations currently used are high-molecular-weight polyethylene (EP) and cross-linked poly- ethylene ( XLPE ). The EP insulation is...rated for 750 C a maximum temperature, and the XLPE insulation is rated for 900C maximum temperature. These insulation materials provide the conductor...The cost of installing PILC with copper conductors is compared to the cost of installing XLPE cable with aluminum conductors in Table 1. The

  18. Polyethylene Nanocomposites for the Next Generation of Ultralow-Transmission-Loss HVDC Cables: Insulation Containing Moisture-Resistant MgO Nanoparticles.

    Science.gov (United States)

    Pourrahimi, Amir Masoud; Pallon, Love K H; Liu, Dongming; Hoang, Tuan Anh; Gubanski, Stanislaw; Hedenqvist, Mikael S; Olsson, Richard T; Gedde, Ulf W

    2016-06-15

    The use of MgO nanoparticles in polyethylene for cable insulation has attracted considerable interest, although in humid media the surface regions of the nanoparticles undergo a conversion to a hydroxide phase. A facile method to obtain MgO nanoparticles with a large surface area and remarkable inertness to humidity is presented. The method involves (a) low temperature (400 °C) thermal decomposition of Mg(OH)2, (b) a silicone oxide coating to conceal the nanoparticles and prevent interparticle sintering upon exposure to high temperatures, and (c) heat treatment at 1000 °C. The formation of the hydroxide phase on these silicone oxide-coated MgO nanoparticles after extended exposure to humid air was assessed by thermogravimetry, infrared spectroscopy, and X-ray diffraction. The nanoparticles showed essentially no sign of any hydroxide phase compared to particles prepared by the conventional single-step thermal decomposition of Mg(OH)2. The moisture-resistant MgO nanoparticles showed improved dispersion and interfacial adhesion in the LDPE matrix with smaller nanosized particle clusters compared with conventionally prepared MgO. The addition of 1 wt % moisture-resistant MgO nanoparticles was sufficient to decrease the conductivity of polyethylene 30 times. The reduction in conductivity is discussed in terms of defect concentration on the surface of the moisture-resistant MgO nanoparticles at the polymer/nanoparticle interface.

  19. The Formula Research of EPDM and CPE Common Insulation for Rubber Cable%橡套电缆用EPDM与CPE共用绝缘橡皮的配方研究

    Institute of Scientific and Technical Information of China (English)

    田维生

    2015-01-01

    The paper researched the insulation property of rubber cable,discussed the basic material system and ingredient system selection,confirmed the insulation rubber pre-production formula,tested insulation rubber property. The test result showed that the formula of EPDM and CPE common insulation fulfill the rubber cable mechanical property,processing property and production requirement.%研究了满足橡套电缆使用的绝缘橡皮的性能特点;探讨了基体材料体系、配合剂体系的选择;试验并确定了绝缘橡皮的中试配方;放线生产并检测了绝缘橡皮的性能。实验结果表明:研制的橡套电缆用EPDM与CPE共用绝缘橡皮,其力学性能、工艺性能均满足橡套电缆使用及生产要求。

  20. Insulation Defects in Outer Sheath of Single-core Cable and Its Differential Maintenance Strategy%单芯电缆外护层绝缘缺陷及其差异化检修策略

    Institute of Scientific and Technical Information of China (English)

    牛海清; 徐涛; 黄嘉盛; 石银霞

    2015-01-01

    The outer sheath of high voltage cable is the first defense line of cable. If it is damaged, it would cause the corrosion of metal sheath and abnormal increase of circulating current. Meanwhile, its broken may endanger the health of main insulation. After the cable is put into operation many years, the decrease of outer sheath insulation does not affect the normal operation of cable in most cases. However, the laying environment of cable is complicated and its design quality is uneven, in some cases (such as bridge laying), the long-term outer sheath defects develops to damage, which will cause serious accident in short term. This paper obtains the resistance monitoring data of outer sheath in Guangzhou, and classi-fies the insulation defects of outer sheath according to the difference of grounding method. According to the development rate of insulation defects in outer sheath and the impact degree on the operation of cable under different laying ways, the differential maintenance strategy of insulation defects in the outer sheath of single-core cable was proposed. The strategy can be used in the judgment of outer sheath fault and insulation repair of power cable.%外护层作为保护电缆的第一道防线,若其损伤可能引起金属护套腐蚀和环流的异常增加,并危及主绝缘健康。电缆投运多年后,其外护层绝缘下降通常并不影响电缆的正常运行,然而地下电缆敷设环境复杂多变且设计质量参差不齐,使得在某些情况下(如桥架敷设)外护层缺陷长期发展至破损,短期内就会引起严重的事故。通过获取广州地区外护层绝缘电阻状态监测数据,针对单芯电缆接地方式的差别对外护层绝缘缺陷进行分类,进而在不同敷设方式下,根据外护层绝缘缺陷的发展速度及对电缆运行的影响程度,提出了单芯电缆外护层绝缘缺陷的差异化检修策略,可应用于输电电缆实际运行中的外护层故障判断、绝缘检修等。

  1. Experimental Study of Water Tree Affecting the Reliability of XLPE Cable Insulation%水树枝影响交联聚乙烯电缆绝缘可靠性的试验研究

    Institute of Scientific and Technical Information of China (English)

    沈庆河; 郑晓泉; 刘嵘; 王金锋; 刘辉

    2015-01-01

    水树枝生长速度较慢,主要影响聚烯烃绝缘电力电缆的寿命;电树枝生长速度较快,主要影响电缆的可靠性。在高频恒定电压(15kV、20kV)下研究交联聚乙烯电缆中水树枝的生长规律,发现聚烯烃绝缘中的水树枝或电树枝存在相互转化的可能性。试验结果表明:干燥的水树枝引发电树枝的几率最高,湿润水树枝引发电树枝的几率最低,水树枝会影响电缆绝缘的可靠性。%Water trees grow very slowly and mainly affect the life of polyolefin insulation power cable. Electrical trees grow very fast and mainly affect the reliability of cable. The growth rule of water tree in XLPE cable under high frequency and constant voltage was studied, and the possibility of mutual transformation between water tree and electrical tree in the polyolefin insulation was found. The results show that the probability of electrical tree intiated by dry water tree and wet water tree is the highest and lowest respectively, and the water tree would affect the reliability of cable insulation.

  2. Nuclear instrumentation cable end seal

    Science.gov (United States)

    Cannon, Collins P.; Brown, Donald P.

    1979-01-01

    An improved coaxial end seal for hermetically sealed nuclear instrumentation cable exhibiting an improved breakdown pulse noise characteristic under high voltage, high temperature conditions. A tubular insulator body has metallized interior and exterior surface portions which are braze sealed to a center conductor and an outer conductive sheath. The end surface of the insulator body which is directed toward the coaxial cable to which it is sealed has a recessed surface portion within which the braze seal material terminates.

  3. Investigation Of Dielectric Behaviors Of Nanoclay Filled Epoxy And PP/NYLON66 Nanocomposites For Cable Insulation Application

    Science.gov (United States)

    Rashmi, Renukappa, N. M.; Siddaramaiah

    2010-10-01

    High performance polymer nanocomposites are emerging as a new class of materials for its demanding applications as insulating material. The outstanding properties of nanoclay make them an attractive candidate for preparing advanced composite materials with multi functional features for electrical and electronics applications. A series of nanoclay incorporated epoxy and polypropylene/nylon66 (50/50 blend) nanocomposites have been prepared via chemical and melt mixing methods respectively. The fabricated nanocomposites have been characterized for dielectric behaviors such as dielectric constant (ɛ r ) and dissipation factor (tan δ). The effect of filler content, frequency, temperature and sea water ageing on dielectric behavior of nanocomposites has been investigated. The variation in the diffusion coefficient (D) of the material aged in water at different temperature with different percentage of nanoclay loaded epoxy and PP/nylon66 nanocomposites were calculated. It is observed that at increase in ageing temperature relatively increases the diffusion coefficient of the material. The measured dielectric results of the nanocomposites reveals that a significant influence of frequency and sea water ageing and marginal change with temperature. Higher dielectric constant was noticed for epoxy nanocomposites as compared to PP/nylon66 composites

  4. Study on Formula of XLPE Cable Insulation Material by Natural Crosslinking%自然交联聚乙烯电缆绝缘料的配方研究

    Institute of Scientific and Technical Information of China (English)

    田丰; 苏朝化; 王小磊

    2014-01-01

    An optimum formula of natural cross-linked cable insulation material was determined by study-ing the effect of silane-PE base material, initiator, anti-pre-crosslinking agent, antioxidant , and catalyst on the properties of cable insulation material, and a cross-linked cable insulation material was prepared by extrusion, then its property was compared with the property of foreign similar product. The results show that the insulation material prepared from the optimum formula could crosslink complete within 72 hours under natural environment after extrusion, and its property is equivalent to that of the foreign simi-lar product, which can replace the foreign similar product.%通过研究硅烷-聚乙烯基料、引发剂、抗预交联剂、抗氧剂、催化剂对电缆绝缘材料性能的影响,确定了硅烷自然交联电缆绝缘料的最佳配方,经挤出制得交联电缆绝缘料,并与国外同类绝缘料进行性能比较分析。结果表明:按最佳配方制得的自然交联电缆绝缘料挤出后在自然环境条件下放置72 h即可完成交联,与国外同类绝缘料的性能相当,可替代国外同类产品。

  5. 21 CFR 890.1175 - Electrode cable.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Electrode cable. 890.1175 Section 890.1175 Food... DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Diagnostic Devices § 890.1175 Electrode cable. (a) Identification. An electrode cable is a device composed of strands of insulated electrical conductors...

  6. Insulation Diagnosis of Water-treed Cables Based on Polarization and Depolarization Current Method%基于PDC法的水树老化电缆绝缘诊断

    Institute of Scientific and Technical Information of China (English)

    蔡钢; 刘曦; 濮峻嵩; 周凯; 黄明

    2016-01-01

    In order to diagnose the insulation condition of 10 kV power cables simply and rapidly, the diagnosis criterion based on polarization-depolarization current (PDC) characteristics for water-treed cables was investigated. The cable samples were performed accelerated water tree ageing experiment through water needle electrode method, and the morphology of water trees in the samples was observed by micro-scope, and then the length of water trees were counted. At the same time, the water-treed samples were tested by the PDC detection system. The DC conductivity and the non-linearity factor of cable insulation were acquired by the measured polarization and depolarization current curves, and the change tendency of the two parameters with the ageing condition of cables was analyzed. The results show that the water tree ageing problems in cable insulation can be assessed effectively via the change of DC conductivity and non-linearity factor.%为对10 kV运行电缆的绝缘状态进行简单、快速诊断,基于极化-去极化电流(PDC)特征研究了针对电缆水树老化的绝缘诊断判据。采用高频高压水针电极法对电缆实验样品进行加速水树老化,使用显微镜定期观察不同老化时期样品中的水树形态,并统计水树长度,同时使用PDC测试平台对水树老化样品进行测试。利用测得的极化和去极化电流曲线求得电缆绝缘层的直流电导率和非线性系数,分析两参数随样品老化程度的变化趋势及规律。结果表明:根据直流电导率和非线性系数的变化能有效判别电缆绝缘中的水树老化问题。

  7. 基于模糊理论的XLPE电缆绝缘状态评估研究%Insulation Condition Assessment Study for XLPE Cable Based on Fuzzy Theory

    Institute of Scientific and Technical Information of China (English)

    张琦; 夏向阳; 杨志峰; 袁秀湘

    2014-01-01

    To improve the insulation diagnosis accuracy of XLPE cable, an insulation diagnosis method based on fuzzy theory was proposed in combination with on-line monitoring technology research status, in which fuzzy analytic hierarchy process(FAHP) was applied to the fuzzy comprehensive assessing, and the corresponding insulation comprehensive assessing model was established. The model used FAHP to re-place analytic hierarchy process(AHP), improving the judgment consistent problem in AHP. Meanwhile the concept of relative deterioration degree was introduced in the fuzzy comprehensive assessing process, and a membership function of relative deterioration degree of insulation parameter was built using fuzzy distribution, making the fuzzy assessing matrix be closer to the actual aging condition of cable insulation. The example analysis shows that the insulation comprehensive assessing model can effectively and reason-ably assess the insulation condition of XLPE cable.%为提高XLPE电缆绝缘诊断精度,结合电缆绝缘在线监测技术研究现状,提出一种以模糊理论为基础,将模糊层次分析法应用于模糊综合评估的XLPE电缆绝缘诊断方法,建立了相应的绝缘综合评估模型。该模型采用模糊层次分析法代替层次分析法对绝缘参数进行权重分配,改进了层次分析法中存在的判断矩阵一致性问题,同时在模糊综合评估过程中引入相对劣化度概念,利用模糊分布建立绝缘参数相对劣化度的隶属函数,从而使模糊评判矩阵更贴近XLPE电缆绝缘的实际老化情况。算例分析表明,基于模糊理论的绝缘综合评估模型用于XLPE电缆的绝缘状态评估是有效、可行的。

  8. 交联聚乙烯抗水树电缆绝缘料配方研究%Formula Study of XLPE Water-tree-retardant Cable Insulation Material

    Institute of Scientific and Technical Information of China (English)

    田丰; 李钫

    2013-01-01

    A best formula of water-tree-retardant cable insulation material was determined by studying the effects of PE base material, crosslinking agent, assistant crosslinking agent and antioxidant on the proper-ties of cable insulation material, including 100 phr low density polyethylene(LDPE), 1.5 phr ethylene-acryl-ic acid copolymer(EAA) as water-tree-retardant, 0.6 phr sorbitol(DBS), 2.2phr dicumyl peroxide(DCP) as crosslinking agent, 1.6 phr triallyl cyanurate(TAC) as assistant crosslinking agent and 2.8 phr antioxidant 300. The comprehensive properties and accelerated aging properties of the water-tree-retardant cable insula-tion material prepared by the best formula were tested. The results show that the properties of the cable insulation material can meet the national standard requirements, and the life of the prepared cable pro-longs obviously, with no less than 40 years of life.%  通过研究聚乙烯基料、交联剂、助交联剂、抗氧剂对电缆绝缘料性能的影响,确定了抗水树电缆绝缘料的最佳配方为:低密度聚乙烯(LDPE)100 phr,抗水树添加剂乙烯-丙烯酸共聚物(EAA)1.5 phr、山梨糖醇(DBS)0.6 phr,交联剂过氧化二异丙苯(DCP)2.2 phr,助交联剂三聚氰酸三烯丙酯(TAC)1.6 phr,抗氧剂3002.8 phr。对该配方制得的抗水树XLPE电缆绝缘料进行综合性能测试及加速老化试验。结果表明:抗水树电缆绝缘料符合国标要求,所制得的电缆寿命明显延长,电缆寿命不低于40年。

  9. 46 CFR 129.340 - Cable and wiring.

    Science.gov (United States)

    2010-10-01

    ... section, the insulation resistance of the remainder of the cable is measured, and the condition of the insulation is unimpaired. (m) All material in a cable splice must be chemically compatible with other material in the splice and with the materials in the cable. (n) Ampacities for conductors must comply...

  10. Economical Aspects of Superconducting Cable

    Science.gov (United States)

    Ohya, Masayoshi

    High-temperature superconducting (HTS) cables are expected to resolve technical problems with power grids because they put large-capacity, low-loss power transmission into a compact package. One problem is replacing old 275-kV oil filled (OF) cables with cross-linked polyethylene insulated vinyl sheath cables (XLPE cables). This is difficult because XLPE cable has a lower transmission capacity than OF cable. In addition, the high concentration of public infrastructure underground makes it extremely difficult to build new ones. However, if 66-kV HTS cables can be installed inside existing underground conduits and can achieve a power capacity equivalent to conventional 275-kV cables, construction costs could be significantly reduced. Moreover, if XLPE cables are used for a 1,000 MVA-class transmission line, then three circuits of nine 275-kV single-core cables would be required, which would incur a transmission loss of 90 W/m/cct. Three circuits of three 66-kV Three-in-One HTS cables, however, with an AC loss of 1 W/m/ph@3 kA, heat invasion of 2 W/m, and cooling system efficiency of 0.1, would reduce transmission loss to less than three-fifths that of XLPE cables.

  11. Semiannual report for the period October 1, 1979-March 31, 1980 of work on: (1) superconducting power transmission system development; (2) cable insulation development. Power Transmission Project Technical Note No. 106

    Energy Technology Data Exchange (ETDEWEB)

    1980-07-07

    Progress is reported in a program whose objective is to develop an underground superconducting power transmission system which is economical and technically attractive to the utility industry. The system would be capable of carrying very large blocks of electric power, and would supplant overhead lines in urban and suburban areas and regions of natural beauty. The program consisted initially of work in the laboratory to develop suitable materials, cryostats, and cable concepts. The materials work covers the development and testing of suitable superconductors and dielectric insulation. The laboratory work has now been extended to an outside test facility which represents an intermediate step between the laboratory scale and a full-scale system. The facility will allow cables several hundred feet long to be tested under realistic conditions. In addition, the refrigerator has been designed for optimum service for utility applications.

  12. Design of Measurement System for Electrical Tree in XLPE Cable Insulation at High Temperature%高温下交联聚乙烯电缆绝缘中树枝测试系统设计

    Institute of Scientific and Technical Information of China (English)

    陈向荣; 徐阳; 王猛; 杨文虎; 刘英; 曹晓珑; 刘景光

    2011-01-01

    An experimental system of electrical treeing in XLPE cable insulation at high temperature was designed. The electrical tree growth and partial discharge characteristics at different temperature in high voltage XLPE cable insulation were studied under 13 Kv power frequency voltages. The results indicate that the effect of temperature on the tree growth is dominant. The whole system can be used to the real-time observation of electrical tree growth and continuous partial discharge measurement at high temperature, which provides an experimental platform for studying the initiation and propagation mechanism of electrical tree in XLPE cable insulation as well as its partial discharge characteristics at high temperature.%设计了高温下交联聚乙烯(XLPE)电缆绝缘中电树枝化的实验系统,在外施工频电压有效值为13 kV下,对不同温度下高压XLPE电缆绝缘中电树枝生长及其局部放电特性进行研究,结果表明,温度对电树枝的生长具有重要影响,整个系统可以用于高温下电树枝生长过程的实时观测与局部放电连续测量,为研究高温下XLPE电缆绝缘中电树枝引发与生长机理及其局部放电特性分析提供了实验研究平台.

  13. 温度梯度下电缆绝缘中空间电荷特性的研究现状%Research Situation of Space Charge Characteristic in Cable Insulation under Temperature Gradient

    Institute of Scientific and Technical Information of China (English)

    吴锴; 陈曦; 王霞; 秦楷; 成永红

    2012-01-01

    系统介绍了国内外温度梯度场下用PEA空间电荷测量方法及温度梯度效应对绝缘内空间电荷的影响,提出了温度梯度场下PEA法测量空间电荷的发展趋势.%A systematic presentation was made on the pulse electro-acoustic (PEA) space charge measurement method under temperature gradient at home and abroad, and the effects of temperature gradient on the space charge in cable insulation. The development trend of the PEA space charge measurement method was proposed.

  14. 高温超导电缆及其低温绝缘研究现状%Present Research Status of High Temperature Superconducting Cable and Its Cryogenic Insulation

    Institute of Scientific and Technical Information of China (English)

    杜伯学; 邢云琪; 傅明利; 侯帅

    2015-01-01

    The research history and current status of high temperature superconducting (HTS)cable in the world are summarized,and the basic structure and insulation requirements of HTS cable body are introduced. Then,the structure and problem of the main insula-tion for HTS cable are analyzed. For liquid nitrogen (LN2 )and several solid insulation materials under low temperature applied in HTS cables,related researches are put forward separately on their dielectric property under low temperature. It can be concluded that, in LN2 ,the breakdown strength of insulation material is higher in DC field than that in ac field;the breakdown strength of polyimide is higher than that of polypropylene laminated paper (PPLP)in both ac and dc field;low temperature can suppress the growth of the electrical tree in epoxy resin.%概述了世界上高温超导电缆的研究历史和现状,介绍了高温超导电缆本体的基本结构及绝缘要求,分析了高温超导电缆主绝缘的结构及存在的问题。针对高温超导电缆中使用的液氮和几种低温固体绝缘材料,分别介绍了其在低温环境下介电性能的相关研究进展。总结发现:液氮的击穿场强受到气泡和电极材料的影响;液氮下绝缘材料的直流击穿场强高于交流击穿场强;聚酰亚胺在液氮下的交直流击穿场强高于聚丙烯层压纸;低温会抑制环氧树脂中电树枝的生长。

  15. Insulating and sheathing materials of electric and optical cables: common test methods part 4-1: methods specific to polyethylene and polypropylene compounds – resistance to environmental stress cracking – measurement of the melt flow index – carbon black and/or mineral filler content measurement in polyethylene by direct combustion – measurement of carbon black content by thermogravimetric analysis (TGA) – assessment of carbon black dispersion in polyethylene using a microscope

    CERN Document Server

    International Electrotechnical Commission. Geneva

    2004-01-01

    Specifies the test methods to be used for testing polymeric insulating and sheathing materials of electric cables for power distribution and telecommunications including cables used on ships. Gives the methods for measurements of the resistance to environmental stress cracking, for wrapping test after thermal ageing in air, for measurement of melt flow index and for measurement of carbon black and/or mineral filler content, which apply to PE and PP coumpounds, including cellular compounds and foam skin for insulation.

  16. Simulation of Typical Defects and Analysis of Insulation Breakdown in 10 kV Cable Accessory%10kV电缆附件典型缺陷仿真与绝缘故障分析

    Institute of Scientific and Technical Information of China (English)

    周凤争; 孟庆霖; 朱晓辉; 郭勇; 沈毅; 齐效华; 刘宝成

    2011-01-01

    Two typical defects produced during the installation period of cable accessories were simulated by finite element method. The results show that the electric field intensity in the defect field is higher than the average electric .field intensity of air (30kV/mm), which can easily induce partial discharge and lead to insulation failure. Finally an insulation failure accident in 10 kV cable accessories was analyzed and corresponding measures were proposed.%采用有限元方法对10 kV电缆附件安装过程中产生的两种典型绝缘缺陷(外半导电层断口处主绝缘割伤、外半导电层断口台阶)进行仿真,研究表明:缺陷处的电场集中,电场强度大于空气的平均击穿场强30kV/cm,容易引发局部放电,导致绝缘故障.通过对一起典型缺陷引起的绝缘事故进行分析,并提出预防措施.

  17. 矿物绝缘伴热带在核电硼加热系统中应用%Overjacket selection for the mineral insulation heating cable in boron heating system

    Institute of Scientific and Technical Information of China (English)

    卢垠西; 廖信全; 张甬; 徐微分

    2015-01-01

    核岛中的硼加热系统由伴热带、连接组件、监控系统组成,用来加热并维持硼酸溶液流过的管道、阀门和泵,以维持流体循环,防止硼酸结晶。矿物绝缘伴热带(以下简称MI伴热带)作为核电硼加热系统中应用最多的伴热带,在硼加热系统中有着重要的作用。文章分析了MI伴热带的性能特征,阐述了MI伴热带在核电硼加热中可能出现的具体情况,为核电硼加热系统伴热带的选用提供理论与实践依据。%Boron heating system which is used to avoid the Boron from crystallization in nuclear power plant contents heating cable,connections and controlling system. Mineral insulation heating cable is widely used in the system,for selecting the right cable,we have done the research on the overjacket.

  18. A cable position sorting method for the balance of current distribution of parallel connected cables

    Energy Technology Data Exchange (ETDEWEB)

    Lee, S.Y. [Northern Taiwan Inst. of Science and Technology, Taipei, Taiwan (China); Yu, C.S. [National Defence Univ., Taoyuan, Taiwan (China); Wang, S.C. [Lung Hwa Univ. of Science and Technology, Taoyuan, Taiwan (China); Chen, Y.L. [MingChi Univ. of Technology, Taipei, Taiwan (China)

    2006-07-01

    In order to meet the high ampacity requirement of a low voltage main feeder, single-core power cables are usually connected in parallel in Taiwan's industrial and commercial power distribution systems. However, parallel connected cables can be problematic due to unequal current distributions among cables of the same phase, causing excessive temperature rise in the heavier loading cables, thus reducing the life expectancy of cable insulation. One of the most effective and economical methods of balancing current distributions is a properly designed cable position arrangement. This paper proposed a cable position sorting method for the balance of current distribution of parallel connected cables. A current distribution calculation method was developed based on mutual inductance theorem and the numerical iteration technique. In order to implement the sorting algorithm, two current distribution indices were proposed for the power loss of all cables and for the largest cable current value. The index values of different cable arrangement patterns generated by a novel permutation reduction method were determined and sorted and 3 cable configurations were studied. Recommendations for the arrangement of cable positions, aiming for more balanced current distributions, were also presented. It was concluded that dividing the cables into subgroups, including only one cable per phase in a subgroup, and arranging the cables in symmetric form can achieve a very balanced current distribution. 5 refs., 14 tabs., 7 figs.

  19. Superconductor cable

    Science.gov (United States)

    Allais, Arnaud; Schmidt, Frank; Marzahn, Erik

    2010-05-04

    A superconductor cable is described, having a superconductive flexible cable core (1) , which is laid in a cryostat (2, 3, 4), in which the cable core (1) runs in the cryostat (2, 3, 4) in the form of a wave or helix at room temperature.

  20. Effect of Fire Retardant Coating on the Insulation Failure of XLPE Insulated Cable in Fire Condition%防火涂料对交联聚乙烯绝缘电缆受热时绝缘失效的影响研究

    Institute of Scientific and Technical Information of China (English)

    王霁

    2011-01-01

    The insulation failure time and temperature of XLPE insulated cable coated with various thickness of fire retardant coating or wrapped by the metal tube with various thickness of fire retardant coating were studied by using infrared radiation heating furnace and insulation resistance measurement system, and based on simulated ISO 834 standard fire condition. The results show that the insulation failure time is proportional to the coating thickness under the two protective ways. The protective effect on the cable wrapped by the metal tube with fire retardant coating is more remarkable.%利用红外辐射加热炉及绝缘电阻测量系统,模拟ISO 834火灾条件,研究了交联聚乙烯绝缘电缆在涂敷不同厚度防火涂料和穿上涂有不同厚度钢结构防火涂料金属管两种保护方式下,绝缘电阻的失效时间及温度.结果表明:在两种保护方式下,交联聚乙烯绝缘电缆的绝缘失效时间与涂层厚度成正比;与直接涂敷电缆防火涂料相比,穿上涂有防火涂料的金属管对交联聚乙烯绝缘电缆的保护效果更明显.

  1. Comparative Study on Thermal Behavior of Base Resin for EHV XLPE Cable Insulation Material%超高压交联电缆绝缘料基础树脂热行为对比研究

    Institute of Scientific and Technical Information of China (English)

    罗军; 陈维清; 俞杰; 陈文卿; 屠德民; 王利群

    2015-01-01

    One kind of domestic EHV cable insulation material (YJ-110) and three kinds of imported. EHV Cable insulation materials were selected as research object in this paper. The molecular weight and thermal behavior of the four samples are characterized by gel permeation chromatography (GPC) and dif-ferential scanning calorimeter (DSC). The results show that the number average molecular weight (Mn) of YJ-110 is almost the same as those of the imported samples, while the weight average molecular weight (Mw) of YJ-110 is among those of the imported samples. Compared with the imported samples, YJ-110 has poorer chain regularity and higher content of short branched chain (SCB), so YJ-110 shows poor crys-tallization capacity.%选用1种国产超高压电缆绝缘料(YJ-110)和3种进口超高压电缆绝缘料作为研究对象,采用凝胶渗透色谱(GPC)和差示扫描量热分析(DSC)等方法对国产料和进口料的分子量和热行为进行了表征。结果表明:国产电缆绝缘料YJ-110的数均分子量(Mn)和3种进口样的数均分子量几乎相同,而重均分子量(Mw)介于3种进口电缆料的之间。与进口电缆料相比,YJ-110的链规整度相对较差,短支链(SCB)含量相对较高,表现出较差的结晶能力。

  2. LOW-LOSS CABLE AND METHOD OF FABRICATION

    Science.gov (United States)

    McCarthy, R.L. et al.

    1960-09-27

    A radiation-resistant coaxial electrical cable capable of carrying very small currents at high voltages with little leakage is described. The cable comprises an inner axial conductor separated from an outer coaxial tubular conductor by annular layer of fibrous silica insulation. The silica insulation is formed by leaching boron from spun horosilicate glass and then heat treating the silica at a high temperature.

  3. 46 CFR 120.340 - Cable and wiring requirements.

    Science.gov (United States)

    2010-10-01

    ... insulation is unimpaired. (n) All material in a cable splice must be chemically compatible with all other material in the splice and with the materials in the cable. (o) Ampacities of wires must meet Section 310... to replace a damaged section of the cable if, before replacing the damaged section, the...

  4. Routine- and on-site tests on accessories for EHV-XLPE-insulated cables; Stueck- und Inbetriebnahmepruefung an Garnituren fuer VPE-isolierte Hochspannungskabel

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, F.; Weissenberg, W. [Pirelli Kabel und Systeme GmbH und Co. KG, Kabelwerk Berlin (Germany)

    1998-12-14

    The authors describe their experience with a new measurement system for use in unshielded rooms. By this method accessories for EHV-XLPE-cables were reliably proofed as partial discharge free at routine- as well as on-site tests. (orig.) [Deutsch] Die Verfasser berichten ueber die Moeglichkeit, durch Messungen in ungeschirmten Pruefaufbauten sowohl bei der Stueck- als auch bei der Inbetriebnahmepruefung die Teilentladungsfreiheit von Garnituren fuer HS-VPE-Kabelanlagen nachzuweisen. (orig.)

  5. Measurement and Analysis of Insulated Interfacial Pressure of Cable Termination in Installation & Operation%安装运行中电缆终端绝缘界面压力的测试分析

    Institute of Scientific and Technical Information of China (English)

    马永其; 郑平; 韩轩; 徐操

    2011-01-01

    A method that the actual measurement is combined with numerical simulation is put forward to investigate the distribution and variation rule of insulated interfacial pressure of HV cable termination in installation or operation. The strain of cable termination is measured using the static or dynamic strain gauge. The finite element model is established, and the reliability of the finite element model is verified by the measurement results. It is analyzed that the insulated interfacial pressure and amplitude of fluctuation is related to voltage and enlarge as the voltage increases. The results of the distribution and variation rule of insulated interfacial pressure obtained by the thermo-me-chanical coupling nonlinear calculation verify the feasibility and reliability of the measurement method.%为了研究安装和运行过程中高压电缆终端绝缘界面压力分布和变化规律,提出了现场实际测景与数值模拟相结合的方法.通过静、动态现场实际安装和运行状况下测量电缆终端应变,根据测量结果验证了所建立的高压电缆终端整体有限元数值模拟模型的可靠性,采用热力耦合非线性计算得到安装和运行状况下绝缘界面压力分布和变化规律.分析说明了安装和运行过程中,绝缘界面压力与电压有关,随着电压增大,绝缘界面压力增大且波动变化幅度增大.结果表明,该方法可行有效,计算结果可信准确,具有实际意义.

  6. Aging analyses of aircraft wire insulation

    Energy Technology Data Exchange (ETDEWEB)

    GILLEN,KENNETH T.; CLOUGH,ROGER LEE; CELINA,MATHIAS C.; AUBERT,JAMES H.; MALONE,G. MICHAEL

    2000-05-08

    Over the past two decades, Sandia has developed a variety of specialized analytical techniques for evaluating the long-term aging and stability of cable insulation and other related materials. These techniques have been applied to cable reliability studies involving numerous insulation types and environmental factors. This work has allowed the monitoring of the occurrence and progression of cable material deterioration in application environments, and has provided insights into material degradation mechanisms. It has also allowed development of more reliable lifetime prediction methodologies. As a part of the FAA program for intrusive inspection of aircraft wiring, they are beginning to apply a battery of techniques to assessing the condition of cable specimens removed from retired aircraft. It is anticipated that in a future part of this program, they may employ these techniques in conjunction with accelerated aging methodologies and models that the authros have developed and employed in the past to predict cable lifetimes. The types of materials to be assessed include 5 different wire types: polyimide, PVC/Glass/Nylon, extruded XL-polyalkene/PVDF, Poly-X, and XL-ETFE. This presentation provides a brief overview of the main techniques that will be employed in assessing the state of health of aircraft wire insulation. The discussion will be illustrated with data from their prior cable aging studies, highlighting the methods used and their important conclusions. A few of the techniques that they employ are widely used in aging studies on polymers, but others are unique to Sandia. All of their techniques are non-proprietary, and maybe of interest for use by others in terms of application to aircraft wiring analysis. At the end of this report is a list showing some leading references to papers that have been published in the open literature which provide more detailed information on the analytical techniques for elastomer aging studies. The first step in the

  7. Common test methods for insulating and sheathing materials of electrical cables - Part 4 Methods specific to polyethylene and polypropylene compounds. Section Two

    CERN Document Server

    International Electrotechnical Commission. Geneva

    1990-01-01

    Gives the methods for measurement of elongation at break after pre-conditioning, for wrapping test after pre-conditioning, for wraping test after thermal ageing in air, for measurement of mass increase, for long-term stability test and for measurement of copper-catalysed oxidative degradation, which apply to polyolefin insulations.

  8. Energy losses of superconducting power transmission cables in the grid

    DEFF Research Database (Denmark)

    Østergaard, Jacob; Okholm, Jan; Lomholt, Karin

    2001-01-01

    One of the obvious motives for development of superconducting power transmission cables is reduction of transmission losses. Loss components in superconducting cables as well as in conventional cables have been examined. These losses are used for calculating the total energy losses of conventional...... as well as superconducting cables when they are placed in the electric power transmission network. It is concluded that high load connections are necessary to obtain energy saving by the use of HTSC cables. For selected high load connections, an energy saving of 40% is expected. It is shown...... that the thermal insulation and cooling machine efficiency are the most important loss element in a superconducting cable system...

  9. Comparison of cable ageing

    Science.gov (United States)

    Plaček, Vít; Kohout, Tomáš

    2010-03-01

    Two cable types, which currently are used in nuclear power plants (NPP) and which are composed by jacket/insulation materials, i.e. PVC/PVC and PVC/PE, were exposed to accelerated ageing conditions, in order to simulate their behavior after 10 years in service. The cables were aged under two different test conditions: With relatively high accelerating ageing speed:Radiation ageing was carried out at room temperature at a dose rate of 2900 Gy/h, followed by thermal ageing at 100 °C. This accelerated ageing condition was fairly fast, but still in compliance with the standards. With moderate ageing speed:The radiation and thermal ageing was performed simultaneously (superimposed) at a dose rate of 2.7-3.7Gy/h and a temperature of 68-70 °C. Such a test condition seems to be very close to the radiation and temperature impact onto the cables in the real NPP service. Finally, mechanical properties were measured to characterize the ageing status of the cables. The purpose of this study was to compare degradation effects, derived from both ageing methods, and to demonstrate that results obtained from high values of accelerating parameters and from fast ageing simulation can be very different from reality. The observed results corroborated this assumption.

  10. DC conduction and breakdown characteristics of Al2O3/cross-linked polyethylene nanocomposites for high voltage direct current transmission cable insulation

    Science.gov (United States)

    Park, Yong-Jun; Kwon, Jung-Hun; Sim, Jae-Yong; Hwang, Ju-Na; Seo, Cheong-Won; Kim, Ji-Ho; Lim, Kee-Joe

    2014-08-01

    We have discussed a cross-linked polyethylene (XLPE) nanocomposite insulating material that is able to DC voltage applications. Nanocomposites, which are composed in polymer matrix mixed with nano-fillers, have received considerable attention because of their potential benefits as dielectrics. The nano-sized alumina oxide (Al2O3)/XLPE nanocomposite was prepared, and three kinds of test, such as DC breakdown, DC polarity reversal breakdown, and volume resistivity were performed. By the addition of nano-sized Al2O3 filler, both the DC breakdown strength and the volume resistivity of XLPE were increased. A little homogeneous space charge was observed in Al2O3/XLPE nanocomposite material in the vicinity of electrode through the polarity reversal breakdown test. From these results, it is thought that the addition of Al2O3 nano-filler is effective for the improvement of DC electrical insulating properties of XLPE.

  11. Physical properties of extrudates containing distillers grains extruded in a twin screw extruder

    Science.gov (United States)

    Extrusion trials were conducted with varying levels of distillers dried grains with solubles (DDGS) along with soy flour, corn flour, fish meal, vitamin mix, mineral mix and net protein content adjusted to 28% using a Wenger TX-52 twin screw extruder. The properties of extrudates obtained with exper...

  12. Cable tensiometer

    Energy Technology Data Exchange (ETDEWEB)

    Park, B.V

    1989-05-30

    This patent describes a weight beam for measuring load on a cable. The weight beam consists of: a beam body; load cell means mounted on the beam body, the load cell means being spaced a predetermined distance from the beam body; clamp means connected to the load cell means and adapted to grip a cable whose tension is to be measured; and adjusting means connected to the load cell to deflect the cable and put the load cell under a tension load, the clamp means and the adjusting means being structurally distinct.

  13. Development of Heat-resistant XLPE Cable and Accessories

    Science.gov (United States)

    Yamada, Hiroyuki; Nakagawa, Shinichi; Murata, Yoshinao; Kishi, Kouji; Katakai, Shoshi

    We have developed heat-resistant XLPE cable and accessories that can be operated at 105°C as the maximum permissible conductor temperature in normal operation. Through this cable system, greater transmission capacity can be achieved using existing cable ducts and without increasing the conductor size of the cable. We have developed heat-resistant XLPE insulation material which has a higher melting point than that of conventional XLPE. The breakdown strength of heat-resistant XLPE cable at 105°C is almost the same as that of conventional XLPE cable at 90°C. The heat deformation of the new cable at 105°C is almost the same as that of conventional XLPE cable at 90°C. Conventional self-pressurized rubber joints can be applied to heat-resistant cable lines with the new waterproof joint compound with low heat resistivity.

  14. 电缆高分子绝缘层整体热老化下红外测温热物性的定量评估%Thermal Properties Quantitive Evaluation of Overall Thermal Aging Cable Insulation Using Infrared Inspection Technique

    Institute of Scientific and Technical Information of China (English)

    吕事桂; 杨立; 范春利; 王为清

    2013-01-01

    电缆高分子绝缘材料因受高温等因素的影响容易发生老化,及时评估其老化状况有利于预防事故发生.文中采用共轭梯度反问题技术结合红外检测手段,对整体热老化后的绝缘材料导热率进行了定量评估.通过电缆热特征分析发现,电缆表面温度并不能真实反映绝缘层的整体热老化状况,而缆芯温度和接线端温度随着绝缘层老化的加剧而升高.文中通过不同红外测温误差和初始假设的数值实验对提出的热物性定量评估方法进行了验证,表明了其定量评估结果的可靠性及稳定性.%The insulation of cable ages easily due to high temperature and other factors. Therefore, it is important to evaluate the ageing process of insulation quantitatively to prevent accident. In this paper, the conductiviy of overall thermal aging insulation is quantitatively evaluated by the conjugate gradient method along with the infrared thermography. Through the analysis of thermal characteristic of cable, it is found that the cable surface temperatures do not response to the overall thermal aging, while temperatures of the cable core and terminal increase with the overall thermal aging of insulation. The reliability and stability of the quantitative evaluation method introduced here are verified by the numerical experiments considering the influence of temperature measurement errors and initial assumptions.

  15. Development of Insulating Material HDPE 5310E for High Speed Communication Cable Compound%高速通信电缆绝缘料HDPE 5310E的开发

    Institute of Scientific and Technical Information of China (English)

    陆小义; 徐振明

    2009-01-01

    介绍了高速通信电缆绝缘料HDPE 5310E的研究开发生产过程、产品的技术指标、性能检测和用户使用情况.结果表明:该产品具有优异的力学性能、介电性能、加工性能和较低成本,各项指标达到了邮电部YD/T 760-1995标准.%Introduced the research and development process development and production technical quota, performance testing and user access situation of high speed cable insulating material of high density polyethy- lene 5310E(HDPE 5310E). The Result showed that the product had excellent mechanical property, dielec- tric property, processing property and low costs, and all properties of the material reached the standard YD/ T 760-1995 of post-telecom branch.

  16. Development of Cable Insulation Resistance Test-driven Based on Embedded Linux System%电缆绝缘电阻测试基于嵌入式LINUX系统的驱动开发

    Institute of Scientific and Technical Information of China (English)

    李琳琳; 王二宝; 孙继银

    2013-01-01

    According to the functional requirements of cable insulation resistance testing,the driver based on embedded Linux system is designed and developed on the basis of Linux universal driver and combining with the proc file system design ideas.The implementation process of driver with the proc file is detailed analyzed.The interrupt and interlock mechanism are used to improve system efficiency and stability.With experiments proving,the driver run speed,memory utilization is high,which can meet the system requirements and has good engineering applications.%在Linux通用驱动程序的基础上,根据电缆绝缘电阻测试的功能需求,结合proc文件系统设计思想,完成基于嵌入式Linux系统的测试仪驱动程序的设计与开发.根据芯片接口设计介绍了读写操作的实现过程;利用中断和互锁机制提高系统效率和稳定性,通过系统调试证明此驱动程序运行时速度快、内存利用率高,能够满足系统需求,具有较好的工程应用价值.

  17. Condition Monitoring of Cables Task 3 Report: Condition Monitoring Techniques for Electric Cables

    Energy Technology Data Exchange (ETDEWEB)

    Villaran, M.; Lofaro, R.; na

    2009-11-30

    For more than 20 years the NRC has sponsored research studying electric cable aging degradation, condition monitoring, and environmental qualification testing practices for electric cables used in nuclear power plants. This report summarizes several of the most effective and commonly used condition monitoring techniques available to detect damage and measure the extent of degradation in electric cable insulation. The technical basis for each technique is summarized, along with its application, trendability of test data, ease of performing the technique, advantages and limitations, and the usefulness of the test results to characterize and assess the condition of electric cables.

  18. Optimal Parameters Multicomponent Mixtures Extruding

    Directory of Open Access Journals (Sweden)

    Ramil F. Sagitov

    2013-01-01

    Full Text Available Experimental research of multicomponent mixtures extruding from production wastes are carried out, unit for production of composites from different types of waste is presented. Having analyzed dependence of multicomponent mixtures extruding energy requirements on die length and components content at three values of angular rate of screw rotation, we received the values of energy requirements at optimal length of the die, angular speed and percent of binding additives.

  19. Wire and Cable Cold Bending Test

    Science.gov (United States)

    Colozza, Anthony

    2010-01-01

    One of the factors in assessing the applicability of wire or cable on the lunar surface is its flexibility under extreme cold conditions. Existing wire specifications did not address their mechanical behavior under cold, cryogenic temperature conditions. Therefore tests were performed to provide this information. To assess this characteristic 35 different insulated wire and cable pieces were cold soaked in liquid nitrogen. The segments were then subjected to bending and the force was recorded. Any failure of the insulation or jacketing was also documented for each sample tested. The bending force tests were performed at room temperature to provide a comparison to the change in force needed to bend the samples due to the low temperature conditions. The results from the bending tests were plotted and showed how various types of insulated wire and cable responded to bending under cold conditions. These results were then used to estimate the torque needed to unroll the wire under these low temperature conditions.

  20. Analysis of Surveyor 3 television cable

    Science.gov (United States)

    Gross, F. C.; Park, J. J.

    1972-01-01

    A sample of cable described as four inches of TV cable, fabric wrapped, which had been exposed to the atmosphere for an unknown period of time, was subjected to extensive chemical analyses for the various components. The fabric was tested using attenuated total reflectance, chloroform extract, aqueous extraction, pyrolysis infrared, and reflectance spectroscopy. The wire insulation was tested using pyrolysis infrared, pyrolysis gas chromatography, differential thermal analysis, attenuated total reflectance subsurface, and tensile tests. Corrosion was also observed in parts of certain wires.

  1. Calibrator device for the extrusion of cable coatings

    Science.gov (United States)

    Garbacz, Tomasz; Dulebová, Ľudmila; Spišák, Emil; Dulebová, Martina

    2016-05-01

    This paper presents selected results of theoretical and experimental research works on a new calibration device (calibrators) used to produce coatings of electric cables. The aim of this study is to present design solution calibration equipment and present a new calibration machine, which is an important element of the modernized technology extrusion lines for coating cables. As a result of the extrusion process of PVC modified with blowing agents, an extrudate in the form of an electrical cable was obtained. The conditions of the extrusion process were properly selected, which made it possible to obtain a product with solid external surface and cellular core.

  2. System and method for sub-sea cable termination

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Qin; Yin, Weijun; Zhang, Lili

    2016-04-05

    An electrical connector includes a first cable termination chamber configured to receive a first power cable having at least a first conductor sheathed at least in part by a first insulating layer and a first insulation screen layer. Also, the electrical connector includes a first non-linear resistive layer configured to be coupled to a portion of the first conductor unsheathed by at least the first insulation screen layer and configured to control a direct current electric field generated in the first cable termination chamber. In addition, the electrical connector includes a first deflector configured to be coupled to the first power cable and control an alternating current electric field generated in the first cable termination chamber.

  3. Analysis and prevention of accident-caused faults in power cable lines

    Directory of Open Access Journals (Sweden)

    Susakova Tatyana V.

    2017-01-01

    Full Text Available To ensure fault-free operation of power cable lines it is essential to make a thorough analysis of the type of faults and their location. The paper considers the most common type of faults and main reasons for cable damage. The case study of cable faults at an urban network (Zabaikalsky Krai shows that the root cause is insulation deterioration, especially with the cables reaching the end of their 35 year lifetime. Therefore, to prevent faults and mitigate the threats it is necessary to increase surveillance of cable systems and use cables with higher reliability and functionality, e.g., XLPE cables.

  4. The unique processing of rubber-insulated wires by radiation

    Science.gov (United States)

    Ishitani, Hayao; Saito, Eisuke; Sasaki, Yasushi

    Ethylene-propylene rubbers are able to be crosslinked (vulcanized) by high energy radiation. The radiation-induced crosslinking of ethylene-propylene copolymer or ethylene-propylene-diene terpolymer depends upon the ethylene/propylene ratio, the molecular weight of the polymer, the unsaturating degree of terpolymer and kinds of tercomponents. The mechanical properties of the crosslinked rubber were affected mainly by the E/P ratio and the molecular weight, and improved by blending of low density polyethylene or ethylene-vinylacetate copolymer. Aging of the rubber, due to kinds and contents of tercomponents, was mostly determined by addition of antioxidants to the compound. We developed EP rubber compounds for wire insulation crosslinked by electron beam radiation and applied to the insulation cores of the ship's cables, in the place of the wire vulcanized conventionally by the pressurized steam in the continuous vulcanizer. The rubber compounds are consisted of ethylene-propylene-diene terpolymer with high ethylene contents, ethylene-vinylacetate copolymer and antioxidants. The high-ethylene polymers are supplied in the shape of pellets, and antioxidants were added to the compounds by means of dry blending of concentrates in which antioxidants are mixed into pellets of ethylene copolymer. The EP rubbers were covered on the copper wire by the extruder, used to plastic material, and irradiated with the electron beam from an accelerator. These insulated cores manufactured on radiation processing had the excellent properties, particularly aging and electrical properties. Further, they are more simply colored. Therefore, they will be considered to be used to other applications. This method of manufacturing of the rubber-insulated wires made it possible to reduce both the material costs by simple compounding and the operating costs by radiation-induced crosslinking, to compare with the conventional compounding and vulcanizing process, in which the materials are

  5. Radiation degradation of plastic insulating materials

    Science.gov (United States)

    Bartoníček, B.; Hnát, V.; Janovský, I.; Pejša, R.

    1995-02-01

    Several types of polymeric compounds, used as insulating and sheathing materials of cables, were subjected to accelerated thermal and radiation ageing and to LOCA test. The stability of materials was evaluated via their mechanical properties, namely strain at break.

  6. 电缆绝缘电阻测试仪中高压电源的设计*%Design of High-Voltage Power Supply of Cable Insulation Resistance Tester

    Institute of Scientific and Technical Information of China (English)

    李琳琳; 王二宝; 孙继银; 恒波; 肖明芳

    2013-01-01

      To meet the power requirements of inputting low voltage and outputting high-voltage during cable insulation resistance test, the paper proposes a new type of active clamp voltage multiplying converters by analyzing and improving the technical of analysis active clamp pulse width modulation and voltage double rectifier. It uses main circuit in active clamp technique to achieve magnetic core flux automatic reset and increases core utilization. The clamp capacitor with other components produces resonant achieving opened switch to zero pressure, which reduces the switching loss and voltage stress. Doubling voltage technique is used to reduce transformer step-up requirements and converter bulk. Taking advantage of negative feedback in control loop,input output voltage into PWM chip and control pulse duty cycle can increase power stability and load characteristics. The software simulation result shows that the converter is able to provide a stable high insulation resistance test voltage.%  为满足电缆绝缘电阻测试“低电压输入,高电压输出”的需求,对有源钳位、脉宽调制和倍压整流等技术分析改进,提出一种新型的有源钳位倍压变换器。主回路中利用有源钳位技术实现磁芯磁通自动复位,提高了磁芯利用率,钳位电容与元器件产生谐振实现开关零压开通,减小开关损耗和电压应力;利用倍压技术降低变压器升压要求,减小了变换器体积;在控制回路中利用负反馈将输出电压输入脉宽调制芯片,控制脉冲占空比,提高了电源稳定性和负载特性。用软件仿真结果表明,该变换器能够为绝缘电阻测试提供稳定的高电压。

  7. Diagnostics and testing of high voltage cable systems

    Energy Technology Data Exchange (ETDEWEB)

    Hyvoenen, P.; Oyegoke, B.; Aro, M.

    2003-07-01

    Reliability demands on electricity generation and distribution are increasing. Power utilities have faced new challenges due to liberalisation of electricity markets, increasing authors regulation and new claims for compensation of unexpected power shut downs. As a result power utilities have to concentrate more on asset management to reduce costs, to postpone investments, to optimise technical management keeping at the same time reliability and power quality at high level. Nowadays it is important to do right things at right place at right time. Maintenance strategy is changing from predictive or repairing maintenance to the condition based maintenance (CBM). Success of CBM depends partly on how good and reliable tools are available to determine condition of electrical apparatus. Cables have been used in electricity distribution since beginning of 20th century. Oldest still in use cables in Finland has been installed late 1940's. Nowadays almost all new distribution systems in urban areas are done using cables. Wide variety of cables are in use. Knowledge of condition and history of cables is not so well documented. Professional skill to install cable systems is disappearing due to outsourcing of maintenance groups. There is a worry about increasing amount of after installation faults due to loosing of professional skills to install cable systems. Wide variety of cable insulation systems and large variety in ages of cables still in use will place hard challenges for cable condition assessment. Earlier studies showed that measurement of insulation resistance is almost only diagnostic measurement performed to cable systems. Knowledge and experience of new diagnostic method is not so widely distributed. Based on previous project, dielectric response (DR) measurement and partial discharge (PD) measurement seemed to be most promising tools for the condition assessment of cable systems. Increased moisture content in oil-paper insulated cable or water trees in

  8. Bulk Electrical Cable Non-Destructive Examination Methods for Nuclear Power Plant Cable Aging Management Programs

    Energy Technology Data Exchange (ETDEWEB)

    Glass, Samuel W. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Jones, Anthony M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Fifield, Leonard S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hartman, Trenton S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-09-01

    This Pacific Northwest National Laboratory milestone report describes progress to date on the investigation of nondestructive test methods focusing particularly on bulk electrical test methods that provide key indicators of cable aging and damage. The work includes a review of relevant literature as well as hands-on experimental verification of inspection capabilities. As nuclear power plants consider applying for second, or subsequent, license renewal to extend their operating period from 60 years to 80 years, it is important to understand how the materials installed in plant systems and components will age during that time and develop aging management programs to assure continued safe operation under normal and design basis events (DBE). Normal component and system tests typically confirm the cables can perform their normal operational function. The focus of the cable test program, however, is directed toward the more demanding challenge of assuring the cable function under accident or DBE. The industry has adopted 50% elongation at break (EAB) relative to the un-aged cable condition as the acceptability standard. All tests are benchmarked against the cable EAB test. EAB, however, is a destructive test so the test programs must apply an array of other nondestructive examination (NDE) tests to assure or infer the overall set of cable’s system integrity. Assessment of cable integrity is further complicated in many cases by vendor’s use of dissimilar material for jacket and insulation. Frequently the jacket will degrade more rapidly than the underlying insulation. Although this can serve as an early alert to cable damage, direct test of the cable insulation without violating the protective jacket becomes problematic. This report addresses the range of bulk electrical NDE cable tests that are or could be practically implemented in a field-test situation with a particular focus on frequency domain reflectometry (FDR). The FDR test method offers numerous advantages

  9. Service Life Estimation Technique of Oxidized XLPE Cables

    Science.gov (United States)

    Hatanaka, Masaki; Nakade, Masahiko; Hirose, Takafumi; Sugimoto, Syuu; Namiki, Yukihiko

    XLPE which is the insulator of the XLPE cable will be oxidized by heat. But, an accident caused by oxidized XLPE has hardly reported until now. Therefore, oxidization of XLPE hasn’t been regard as important. But recently we found that XLPE cable used for a long time could break down due to the oxidization of XLPE by simulation result. So, we developed the service life estimation technique of oxidized XLPE cables used FT-IR.

  10. Resistive cryogenic cable, phase III. Final report, April 18, 1974--March 31, 1977

    Energy Technology Data Exchange (ETDEWEB)

    None

    1977-01-01

    Work performed during 3 years of research on development of a foam-insulated underground cryogenic power transmission cable is reported. Information is included on the cryogenic envelope investigation; evaluation and aging study of electrical insulation; test system specifications; and cable system design and cost studies. (LCL)

  11. 46 CFR 111.60-1 - Construction and testing of cable.

    Science.gov (United States)

    2010-10-01

    ... (incorporated by reference; see 46 CFR 110.10-1), where applicable, for cables rated above 5,000 volts. (d) Electrical cable that has a polyvinyl-chloride insulation with a nylon jacket (Type T/N) must meet either UL... 46 Shipping 4 2010-10-01 2010-10-01 false Construction and testing of cable. 111.60-1 Section...

  12. Effect of Temperature in Electrocapacity In-Process Control of Cable Products

    Directory of Open Access Journals (Sweden)

    Starikova Nadezda

    2016-01-01

    Full Text Available In this paper the analysis of temperature effect on the value of cable capacitance per unit length during its manufacture is provided. The physical model of cable product is developed. This model involves heat and electric components. The single-wire electric cable NV-3 insulated with plastic compound of PVC is chosen as a research object.

  13. RDX/Sylgard extrudable explosive development

    Energy Technology Data Exchange (ETDEWEB)

    Osborn, A.G.; Schmitz, G.T.; Stallings, T.L.; West, G.T.; Ashcraft, R.W.

    1977-10-01

    Formulation procedures for X-0208, an 80 percent RDX/20 percent Sylgard extrudable, have been developed. The extrudable explosive, made from a mixture of micronized RDX and Class E RDX, will sustain detonation in a 1.65 mm channel and can be mechanically extruded into ribbon-type configurations.

  14. Filter-extruded liposomes revisited

    DEFF Research Database (Denmark)

    Hinna, Askell; Steiniger, Frank; Hupfeld, Stefan;

    2016-01-01

    Filter-extrusion is a widely used technique for down-sizing of phospholipid vesicles. In order to gain a detailed insight into size and size distributions of filter-extruded vesicles composed of egg phosphatidyl-choline (with varying fractions of cholesterol) – in relation to extrusionparameters...

  15. Evaluation of foam-skin cables for aerial applications

    Science.gov (United States)

    Samuelson, G. R.

    Since the introduction of foam-skin filled cables, there has been considerable discussion within the Industry, both pro and con, regarding the acceptability of foam-skin filled cables for aerial application. This paper reports on results obtained from a study undertaken to evaluate the changes in transmission properties of such cables in a simulated aerial environment. Cable samples produced by six cable manufacturers using conventional, high-temperature drip-resistant filling compounds with a petrolatum base were subjected to temperature cycling from -40 F to 140 F. Transmission parameters were measured at 1, 150 and 772 kHz and compared to initial values. A solid polypropylene insulated filled cable was included for reference. The results show that foam-skin petrolatum based filled cables exhibit stable electrical characteristics when exposed to cycled temperature extremes.

  16. On-line partial discharge measurements and off-line dielectric spectroscopy measurements of six 115 kV XLPE cable systems

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2009-07-01

    This paper reported on a study in which partial discharge (PD) measurements were performed on 6 underground transmission cable circuits to determine the effectiveness of PD measurements on fluid fill cables. The cables were between 37 and 56 years old. PD activity was detected from the terminations of H11L and H3L Cable 2. However, for cables from H3L Basin TS to Mill Street junction, PD activity was detected originating from within the main cable insulation.

  17. Analysis of Statistical Distributions of Energization Overvoltages of EHV Cables

    DEFF Research Database (Denmark)

    Ohno, Teruo; Ametani, Akihiro; Bak, Claus Leth;

    Insulation levels of EHV systems have been determined based on the statistical distribution of switching overvoltages since 1970s when the statistical distribution was found for overhead lines. Responding to an increase in the planned and installed EHV cables, the authors have derived...... the statistical distribution of energization overvoltages for EHV cables and have made clear their characteristics compared with those of the overhead lines. This paper identifies the causes and physical meanings of the characteristics so that it becomes possible to use the obtained statistical distribution...... for the determination of insulation levels of cable systems....

  18. Cable Sliding at Supports in Cable Structures

    Institute of Scientific and Technical Information of China (English)

    魏建东

    2004-01-01

    To develop an effective numerical method for the cable sliding problem in cable structures, two-node catenary cable element was built to model the cables based on analytical solution of elastic catenary. Cooperated with Newton method, continuation method was used to solve the nonlinear equations. This approach is more efficient than using Newton method only and has a wider range to select initial values for the process to converge. The relationship between the tension on a cable segment and its unstrained length was derived and used to calculate the unbalanced cable tensions at the supports. An example is presented to show the correctness and efficiency of the proposed method.

  19. VT Cable Systems 2013

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) The VT Cable dataset (CABLE2013) includes lines depicting the extent of Vermont's cable modem broadband system as of 6/30/2013 in addition to...

  20. Space charge accumulation in polymeric high voltage DC cable systems

    NARCIS (Netherlands)

    Bodega, R.

    2006-01-01

    One of the intrinsic properties of the polymeric high voltage (HV) direct current (DC) cable insulation is the accumulation of electrostatic charges. Accumulated charges distort the initial Laplacian distribution of the electric field, leading to a local field enhancement that may cause insulation d

  1. Cryostat for a high-temperature superconducting power cable

    NARCIS (Netherlands)

    Chevtchenko, O.A.; Smit, J.J.; Geschiere, A.

    2010-01-01

    Cryostat for a high-temperature superconducting power cable, comprising concentric tubes, an annular region between said tubes, wherein a multilayer thermal insulation and getter material for supporting high vacuum conditions are provided in said annular region, and wherein the multilayer insulation

  2. Analysis of Statistical Distributions of Energization Overvoltages of EHV Cables

    DEFF Research Database (Denmark)

    Ohno, Teruo; Ametani, Akihiro; Bak, Claus Leth

    Insulation levels of EHV systems have been determined based on the statistical distribution of switching overvoltages since 1970s when the statistical distribution was found for overhead lines. Responding to an increase in the planned and installed EHV cables, the authors have derived the statist......Insulation levels of EHV systems have been determined based on the statistical distribution of switching overvoltages since 1970s when the statistical distribution was found for overhead lines. Responding to an increase in the planned and installed EHV cables, the authors have derived...... the statistical distribution of energization overvoltages for EHV cables and have made clear their characteristics compared with those of the overhead lines. This paper identifies the causes and physical meanings of the characteristics so that it becomes possible to use the obtained statistical distribution...... for the determination of insulation levels of cable systems....

  3. Process for making RF shielded cable connector assemblies and the products formed thereby

    Science.gov (United States)

    Fisher, A.; Clatterbuck, C. H. (Inventor)

    1973-01-01

    A process for making RF shielded cable connector assemblies and the resulting structures is described. The process basically consists of potting wires of a shielded cable between the cable shield and a connector housing to fill in, support, regidize, and insulate the individual wires contained in the cable. The formed potting is coated with an electrically conductive material so as to form an entirely encompassing adhering conductive path between the cable shield and the metallic connector housing. A protective jacket is thereby formed over the conductive coating between the cable shield and the connector housing.

  4. Cable Television Service; Cable Television Relay Service.

    Science.gov (United States)

    Federal Register, 1972

    1972-01-01

    The rules and regulations of the Federal Communications Commission (FCC) concerning cable television service and cable relay service are presented along with the comments of the National Cable Television Association, the National Association of Broadcasters, the Association of Maximum Service Telecasters, and a major group of program suppliers.…

  5. Electromagnetic Transients in Power Cables

    DEFF Research Database (Denmark)

    Silva, Filipe Faria Da; Bak, Claus Leth

    of electromagnetic phenomena associated to their operation, among them electromagnetic transients, increased as well. Transient phenomena have been studied since the beginning of power systems, at first using only analytical approaches, which limited studies to more basic phenomena; but as computational tools became...... concerning HVAC cables. An important topic that is not covered in this book is measurements protocols/ methods. The protocols used when performing measurements on a cable depend on what is to be measured, the available equipment and accessibility. Readers interested in the topic are referred to search....... The chapter ends by proposing a systematic method that can be used when doing the insulation co-ordination study for a line, as well as the modelling requirements, both modelling depth and modelling detail of the equipment, for the study of the different types of transients followed by a step-by-step generic...

  6. Research of A photovoltaic and Building cable in using flame weather type silane crosslinking Insulation material%一种光伏及建筑电缆用阻燃耐候型硅烷交联绝缘料的研究

    Institute of Scientific and Technical Information of China (English)

    张丽本; 陈敏; 顾金云; 邓之俊

    2014-01-01

    本文简述了电线电缆用阻燃耐候型硅烷交联聚乙烯绝缘料的交联原理、配方、工艺、分类、设备,并介绍了硅烷自然交联聚乙烯绝缘料在实际应用以及使用过程中呈现出的特征和该材料交联状况的影响因素。针对该材料对光伏与建筑电缆进行分析和探讨。%This paper describes the types of wire and cable flame retardant weather silane crosslinked polyethylene crosslinked insulation material principle, formula, process, classification, equip-ment, and introduced silane XLPE insulation material naturally pres-ent in the practical application and use of the process the characteris-tics and condition of the material cross-linked factors. The materials for the photovoltaic and building cables for analysis and discussion.

  7. Self-contained cable systems offer advantages

    Energy Technology Data Exchange (ETDEWEB)

    Morello, A.S.; Occhini, E.

    1977-05-01

    Low-pressure oil-filled (LPOF) cable systems, while seldom used in this country, have several advantages of interest to engineers. Less oil and insulating paper is required for low-pressure than for the more commonly used high-pressure systems because of the single core. The lower pessure offers safety features in the event of accidental oil loss. LPOF cables are used internationally because of their good thermal characteristics. Applications besides ac transmission lines include underground and submarine cables, such as those connecting islands with mainland facilities. Cooling can be accomplished either by circulating oil inside the central duct or circulating water through parallel nonmetallic pipes. Forced-cooling of the LPOF cables is less complicated, which allows them to have higher current ratings and makes them more adaptable to thermal transients. Conductor cooling, which increases capacity but prohibits overloads in LPOF cables, is the only system available to high voltage (HVDC) cables. Several experimental and demonstration cable systems are described. (DCK)

  8. Development and Outlook of Insulating Materials for High Voltage Direct Current Cables%高压直流电缆绝缘材料的发展与展望

    Institute of Scientific and Technical Information of China (English)

    张翀; 查俊伟; 王思蛟; 巫运辉; 闫轰达; 李维康; 陈新; 党智敏

    2016-01-01

    针对高压直流电缆的发展历史,介绍了高压直流电缆的基本原理、应用现状以及技术瓶颈,指出我国研发高压直流电缆的必要性和紧迫性,并对未来高压直流电缆的发展方向进行了展望.%The basic principle, application status, and technical bottlenecks of high voltage direct current (HVDC) cables were introduced according to the history of HVDC cables, and the necessity and urgency for developing HVDC cables were pionted out in China. The future development direction of HVDC cables was prospected.

  9. Electrically and Thermally Insulated Joint for Liquid Nitrogen Transfer

    DEFF Research Database (Denmark)

    Rasmussen, Carsten; Jensen, Kim Høj; Holbøll, Joachim T.

    1999-01-01

    A prototype of a superconducting cable is currently under construction. The cable conductor is cooled by liquid nitrogen in order to obtain superconductivity. The peripheral cooling circuit is kept at ground potential. This requires a joint which insulates both electrically and thermally. The des......A prototype of a superconducting cable is currently under construction. The cable conductor is cooled by liquid nitrogen in order to obtain superconductivity. The peripheral cooling circuit is kept at ground potential. This requires a joint which insulates both electrically and thermally...

  10. Cable Tensiometer for Aircraft

    Science.gov (United States)

    Nunnelee, Mark (Inventor)

    2008-01-01

    The invention is a cable tensiometer that can be used on aircraft for real-time, in-flight cable tension measurements. The invention can be used on any aircraft cables with high precision. The invention is extremely light-weight, hangs on the cable being tested and uses a dual bending beam design with a high mill-volt output to determine tension.

  11. Studies on the Effect of Accelerated Thermal Aging on Electrical and Physicochemical Properties of XLPE Cable

    Institute of Scientific and Technical Information of China (English)

    KIM Chon-ung; JIN Zhi-jian; JIANG Ping-kai; ZHU Zi-shu; LIU Fei; KIM Ui-chon

    2007-01-01

    The degradation of crosslinked polyethylene (XLPE) cable insulation during service, such as thermo-oxidation and water treeing may lead to a premature electrical breakdown of the XLPE insulation cables. Therefore,it is necessary to optimize the period of replacement to evenly distribute the replacement cost by ascertaining the deterioration degree. Estimation of the aging degree is at present the most important task for diagnosis of the residual lifetime of the power cable insulation. This paper presents a study on the changes in the dielectric properties of the thermally aged XLPE cables in the frequency range from 0.07~10 MHz. Based on electrical and physicochemical characterization, some new "dactylograms" for the thermally aged XLPE cable insulation have been proposed.

  12. Computation of Electric Field and Thermal Properties of 3-Phase Cable

    Directory of Open Access Journals (Sweden)

    Hemsingh Lunavath

    2012-06-01

    Full Text Available The high voltage electric power is generally transmitted by underground cable in urban, considering about the high cost for underground cable, it is necessary for us to get accurately biggest ampacity of cables in order to ensure the operation of cables in safe. The Cross linked polyethylene (XLPE insulated power cables are used for transmission and distribution of electrical power for higher voltage level. In this paper a three phase high voltage power cable buried in soil and it can be used to investigate electrical and thermal properties of cable. An underground cable of 132kV electric field, voltage distribution using finite element method (FEM, analytical method for calculating ampacity of cable and temperature distribution is presented and verified same by using COMSOL multiphysics software.

  13. Energy cables: defects research and identification; Cables d'energie: recherche et identification de defauts

    Energy Technology Data Exchange (ETDEWEB)

    Kuzyk, H. [Electricite de France (EDF), 75 - Paris (France)

    2006-05-15

    This article presents the different types of power cables and their possible defects (external and internal). Then it describes the procedure used for defects detection and for the identification of the type of defect (measurement of the insulation resistance, dielectric test, continuity measurement). (J.S.)

  14. Heat transfer between the superconducting cables of the LHC accelerator magnets and the superfluid helium bath

    CERN Document Server

    Granieri, Pier Paolo; Tommasini, D

    In this thesis work we investigate the heat transfer through the electrical insulation of superconducting cables cooled by superfluid helium. The cable insulation constitutes the most severe barrier for heat extraction from the superconducting magnets of the CERN Large Hadron Collider (LHC). We performed an experimental analysis, a theoretical modeling and a fundamental research to characterize the present LHC insulation and to develop new ideas of thermally enhanced insulations. The outcome of these studies allowed to determine the thermal stability of the magnets for the LHC and its future upgrades. An innovative measurement technique was developed to experimentally analyze the heat transfer between the cables and the superfluid helium bath. It allowed to describe the LHC coil behavior using the real cable structure, an appropriate thermometry and controlling the applied pressure. We developed a new thermally enhanced insulation scheme based on an increased porosity to superfluid helium. It aims at withstan...

  15. Modified Low Density Polyethylene by Nano-fills as Insulating Material of DC Cable (Ⅱ)%纳米粒子改性聚乙烯直流电缆绝缘材料研究(Ⅱ)

    Institute of Scientific and Technical Information of China (English)

    吴锴; 陈曦; 王霞; 成永红; 屠德民

    2013-01-01

    在电缆聚乙烯材料中添加一种新型纳米粒子可以有效改善材料中的空间电荷积聚,提高其直流击穿强度和体积电阻率.为深入了解此纳米粒子作用机理,基于电声脉冲法(PEA)和充电-放电电流法,分别测量了在不同温度下、不同纳米含量时聚乙烯纳米复合材料的极化/去极化特性.用PEA方法得到不同温度下材料的平均电荷体密度、视在迁移率和陷阱深度,结果表明,20~40℃下,纯聚乙烯及聚乙烯纳米复合材料试样内的陷阱以浅陷阱分布为主;80℃下,当聚乙烯中纳米粒子质量分数>3%时,会增加复合材料陷阱深度.用充电-放电电流法计算得到材料的迁移率,可知在20~60℃内,不同试样迁移率的变化主要由纳米粒子和温度共同作用产生,而在60~80℃内,迁移率的变化则是温度起主要作用.分析认为,电荷输运受到陷阱与温度的影响是导致电阻率变化的主要原因,而在温度梯度场下,聚乙烯纳米复合材料电阻率的正温度系数趋势是抑制材料内空间电荷积聚的主要原因.%Adding a novel nano filler in the insulation of high voltage direct current (HVDC) cable is proved to be capable of restricting space charge accumulation, and enhancing DC breakdown strength and volume resistivity of the low density polyethylene (LDPE). In order to further study the working mechanism of the nano filler, the polarization and depolarization characteristics of pure LDPE and LDPE nanocomposites with different nano fillers under different temperatures were tested based on the pulsed electro-acoustic ( PEA) method and charging / discharging current method, respectively. Parameters, including the mean volume density of space charge, apparent trap-controlled mobility and trap depth distribution, were achieved by the PEA method: shallow traps were dominant in pure LDPE and LDPE nanocomposites under 20~40 ℃; the trap depth increased under 80 ℃ in

  16. Modelling of long High Voltage AC Cables in the Transmission System

    DEFF Research Database (Denmark)

    Gudmundsdottir, Unnur Stella

    , EMTDC/PSCAD is provided. A typical HV AC underground power cable is formed by 4 main layers, namely; Conductor-Insulation-Screen-Insulation. In addition to these main layers, the cable also has semiconductive screens, swelling tapes and metal foil. For high frequency modelling in EMT-based software...... and field measurement results. This is because of intersheath mode reflecting from the crossbonding points. The second main part of the work deals with improving the cable model based on the findings from analysis of the field measurements. The existing EMT-based models have the configuration for cables...

  17. Estudio de la cargabilidad de cables de alta tensión de aislamiento sólido con las variaciones periódicas de la carga; Study of the current capacity of solid insulation high voltage cables with periodical changes of load

    Directory of Open Access Journals (Sweden)

    Juan F Zuñinga

    2011-02-01

    Full Text Available Se plantean los resultados obtenidos al introducir una corrección al método desarrollado en el CIPEL para elcálculo de la cargabilidad de cables soterrados considerando las variaciones periódicas de la curva de cargadiaria y la impedancia compleja del medio que rodea a la instalación a partir del empleo de funciones Bessel yHankel. La validación de la corrección propuesta se realizó mediante el cálculo, con y sin la corrección planteada,de la temperatura superficial de cables en servicio por el método de cálculo propuesto y su comparación conlos medidos en la superficie de dichos cables  This work presents the results obtaines after the introduction of a correction to the method developed in theCIPEL to calculate the current capacity of underground cables considering the periodical chnages of the loadchanges of the daily load curve and the complex impedance of the enviroment sorrounding the installation usingBessel and Hankel funtions.The validity of the proposed correction was carried out calculating the surfacetemperature of the cables in service by means of the calculating method  with and whithout the correction  andthe  comparison of these values with the temperature mesured on the surface of the cables

  18. Bulk Electrical Cable Non-Destructive Examination Methods for Nuclear Power Plant Cable Aging Management Programs

    Energy Technology Data Exchange (ETDEWEB)

    Glass, Samuel W. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Jones, Anthony M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Fifield, Leonard S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hartman, Trenton S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-09-01

    This Pacific Northwest National Laboratory milestone report describes progress to date on the investigation of nondestructive test methods focusing particularly on bulk electrical test methods that provide key indicators of cable aging and damage. The work includes a review of relevant literature as well as hands-on experimental verification of inspection capabilities. As nuclear power plants consider applying for second, or subsequent, license renewal to extend their operating period from 60 years to 80 years, it is important to understand how the materials installed in plant systems and components will age during that time and develop aging management programs to assure continued safe operation under normal and design basis events (DBE). Normal component and system tests typically confirm the cables can perform their normal operational function. The focus of the cable test program, however, is directed toward the more demanding challenge of assuring the cable function under accident or DBE. The industry has adopted 50% elongation at break (EAB) relative to the un-aged cable condition as the acceptability standard. All tests are benchmarked against the cable EAB test. EAB, however, is a destructive test so the test programs must apply an array of other nondestructive examination (NDE) tests to assure or infer the overall set of cable’s system integrity. Assessment of cable integrity is further complicated in many cases by vendor’s use of dissimilar material for jacket and insulation. Frequently the jacket will degrade more rapidly than the underlying insulation. Although this can serve as an early alert to cable damage, direct test of the cable insulation without violating the protective jacket becomes problematic. This report addresses the range of bulk electrical NDE cable tests that are or could be practically implemented in a field-test situation with a particular focus on frequency domain reflectometry (FDR). The FDR test method offers numerous advantages

  19. External heating of electrical cables and auto-ignition investigation.

    Science.gov (United States)

    Courty, L; Garo, J P

    2017-01-05

    Electric cables are now extensively used for both residential and industrial applications. During more than twenty years, multi-scale approaches have been developed to study fire behavior of such cables that represents a serious challenge. Cables are rather complicated materials because they consist of an insulated part and jacket of polymeric materials. These polymeric materials can have various chemical structures, thicknesses and additives and generally have a char-forming tendency when exposed to heat source. In this work, two test methods are used for the characterization of cable pyrolysis and flammability. The first one permits the investigation of cable pyrolysis. A description of the cable mass loss is obtained, coupling an Arrhenius expression with a 1D thermal model of cables heating. Numerical results are successfully compared with experimental data obtained for two types of cable commonly used in French nuclear power plants. The second one is devoted to ignition investigations (spontaneous or piloted) of these cables. All these basic observations, measurements and modelling efforts are of major interest for a more comprehensive fire resistance evaluation of electric cables. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Twin-Screw Extruders in Ceramic Extrusion

    Science.gov (United States)

    Wiedmann, Werner; Hölzel, Maria

    The machines mainly used for compounding plastics, chemicals and food are co-rotating, closely intermeshing twin-screw extruders. Some 30 000 such extruders are in use worldwide, about 1/3 are ZSKs from Coperion Werner & Pfleiderer, Stuttgart. In the chemical industry more and more batch mixers are being replaced by continuous twin-screw kneaders.

  1. Properties of extruded expandable breadfruit products

    Science.gov (United States)

    Dried breadfruit was extruded with a twin screw extruder to develop a value-added expanded fruit product. This research studied the effects of barrel temperature (120-160°C), moisture content (13-25%), feeding rate (13-25 kg/h) and screw speed (115-175rpm) on physicochemical properties (bulk densit...

  2. Safer cables; Des cables plus surs

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2005-02-01

    Sixteen years after its adoption, the European construction products directive (CPD) will have soon a strong impact on the characteristics of electrical and communication cables used in European buildings and facilities. Among the six main requirements of this directive, the fire protection safety is a growing up concern and the electric cables have to be tested with respect to their fire resistance to become conformable with the directive. The cable industry has taken up the challenge. (J.S.)

  3. Recent Progress in Electrical Insulation Techniques for HTS Power Apparatus

    Science.gov (United States)

    Hayakawa, Naoki; Kojima, Hiroki; Hanai, Masahiro; Okubo, Hitoshi

    This paper describes the electrical insulation techniques at cryogenic temperatures, i.e. Cryodielectrics, for HTS power apparatus, e.g. HTS power transmission cables, transformers, fault current limiters and SMES. Breakdown and partial discharge characteristics are discussed for different electrical insulation configurations of LN2, sub-cooled LN2, solid, vacuum and their composite insulation systems. Dynamic and static insulation performances with and without taking account of quench in HTS materials are also introduced.

  4. Evaluation of cable ageing in Nuclear Power Plants; Evaluacion del envejecimiento de cables en centrales nucleares

    Energy Technology Data Exchange (ETDEWEB)

    Lopez Vergara, T. [Empresarios Agrupados, A. I. E. Madrid (Spain); Alonso Chicote, J. [TECNATOM, S. A. (Spain); Burnay, S. [AEA Technology (UK)

    2000-07-01

    The majority of power, control and instrumentation cables in nuclear power plants use polymers as their basic material for insulation and jacket. In many cases, these cables form part of safety-related circuits and should therefore be capable of operating correctly under both normal and accident conditions. Since polymeric materials are degraded by the long term action of the radiation and thermal environments found in the plant, it is important to be able to establish the cable condition during the plant lifetime. Nowadays there are a number of different methods to evaluate the remaining lifetime of cables. In the case of new plants, or new cables in old plants, accelerated ageing tests and predictive models can be used to establish the behaviour of the cable materials under operating conditions. There are verified techniques and considerable experience in the definition of predictive models. This type of approach is best carried out during the commissioning stage or in the early stages of operation. In older plants, particularly where there is a wide range of cable types in use, it is more appropriate to use condition monitoring methods to establish the state of degradation of cables in-plant. Over the last 10 years there have been considerable developments in methods for condition monitoring of cables and a tool-box of practical techniques are now available. There is no single technique which is suitable for all cable materials but the range of methods covers nearly all of the types currently in use, at present, the most established methods are the indented, thermal analysis (OIT, OITP and TGA) and dielectric loss measurements, All of these are either non-destructive methods or require only micro-samples of material. (Author) 15 refs.

  5. Cable Overheating Risk Warning Method Based on Impedance Parameter Estimation in Distribution Network

    Science.gov (United States)

    Yu, Zhang; Xiaohui, Song; Jianfang, Li; Fei, Gao

    2017-05-01

    Cable overheating will lead to the cable insulation level reducing, speed up the cable insulation aging, even easy to cause short circuit faults. Cable overheating risk identification and warning is nessesary for distribution network operators. Cable overheating risk warning method based on impedance parameter estimation is proposed in the paper to improve the safty and reliability operation of distribution network. Firstly, cable impedance estimation model is established by using least square method based on the data from distribiton SCADA system to improve the impedance parameter estimation accuracy. Secondly, calculate the threshold value of cable impedance based on the historical data and the forecast value of cable impedance based on the forecasting data in future from distribiton SCADA system. Thirdly, establish risks warning rules library of cable overheating, calculate the cable impedance forecast value and analysis the change rate of impedance, and then warn the overheating risk of cable line based on the overheating risk warning rules library according to the variation relationship between impedance and line temperature rise. Overheating risk warning method is simulated in the paper. The simulation results shows that the method can identify the imedance and forecast the temperature rise of cable line in distribution network accurately. The result of overheating risk warning can provide decision basis for operation maintenance and repair.

  6. UtilityTelecom_CABLE2005

    Data.gov (United States)

    Vermont Center for Geographic Information — The VT Cable System dataset (CABLE2005) includes lines depicting the extent of Vermont's cable system as of 12/31/2005. Numerous cable companies provide service in...

  7. High temperature superconductor cable concepts for fusion magnets

    CERN Document Server

    AUTHOR|(CDS)2078397

    2013-01-01

    Three concepts of high temperature superconductor cables carrying kA currents (RACC, CORC and TSTC) are investigated, optimized and evaluated in the scope of their applicability as conductor in fusion magnets. The magnetic field and temperature dependence of the cables is measured; the thermal expansion and conductivity of structure, insulation and filling materials are investigated. High temperature superconductor winding packs for fusion magnets are calculated and compared with corresponding low temperature superconductor cases.

  8. Common test methods for insulating and sheathing materials of electric cables part 1-1: methods for general application : measurement of thickness and overall dimensions : tests for determining the mechanical properties

    CERN Document Server

    International Electrotechnical Commission. Geneva

    2001-01-01

    Gives the methods for measuring thicknesses and overall dimensions, and for determining the mechanical properties, which apply to the most common types of insulating and sheathing compounds (elastometic, PVC, PE, PP, etc.).

  9. Effect of oxygen concentration on fire growth of various types of cable bending in horizontal and vertical orientations

    Science.gov (United States)

    Pangaribuan, Adrianus; Dhiputra, I. M. K.; Nugroho, Yulianto S.

    2017-03-01

    Electrical cable is a whole of the material including metal (cooper) conductor and its insulation, when an electrical cable is flowed by electric current, based on its own capacity, the temperature of cable conductor increases gradually. If the current flows above the cable carrying capacity, then an extreme temperature rises are expected. When temperature increase, the electric current flow inside cable conductor will decrease gradually related to the resistance and could occur repeatedly in a period. Since electrical faults on electrical cable system are often suspected as the cause of fires, thus this research aims to investigate measures of preventing the fire to start by means of controlling oxygen concentration in a cable compartment. The experimental work was conducted in laboratory by using electrical power cable of 1.5 mm2 size. Two transparent chambers were applied for studying the effect of vertical and horizontal orientations on the cable temperature rise, under various oxygen concentration of the gas streams. In the present work, the electrical was maintained at a constant level during a typical test run. Parametric studies reported in the paper include the use of a bare and insulated cables as well as the bending shape of the cable lines of a straight cable, coiled cable and randomly bent cable which were loaded with the same electric load and oxygen concentration in the gas supply.

  10. Cable Television: Franchising Considerations.

    Science.gov (United States)

    Baer, Walter S.; And Others

    This volume is a comprehensive reference guide to cable television technology and issues of planning, franchising, and regulating a cable system. It is intended for local government officials and citizens concerned with the development of cable television systems in their communities, as well as for college and university classes in…

  11. Cable Television: Franchising Considerations.

    Science.gov (United States)

    Baer, Walter S.; And Others

    This volume is a comprehensive reference guide to cable television technology and issues of planning, franchising, and regulating a cable system. It is intended for local government officials and citizens concerned with the development of cable television systems in their communities, as well as for college and university classes in…

  12. Colleges and Cable Franchising.

    Science.gov (United States)

    Glenn, Neal D.

    After noting issues of audience appeal and financial and philosophical support for educational broadcasting, this paper urges community colleges to play an active role in the process of cable franchising. The paper first describes a cable franchise as a contract between a government unit and the cable television (CATV) company which specifies what…

  13. Cable Supported Bridges

    DEFF Research Database (Denmark)

    Gimsing, Niels Jørgen

    Cable supported bridges in the form of suspension bridges and cable-stayed bridges are distinguished by their ability to overcome large spans.The book concentrates on the synthesis of cable supported bridges, covering both design and construction aspects. The analytical part covers simple methods...

  14. Statistical Distribution of Energization Overvoltages of EHV Cables

    DEFF Research Database (Denmark)

    Ohno, Teruo; Bak, Claus Leth; Ametani, Akihiro

    2013-01-01

    those on the overhead lines with respect to maximum, 2%, and mean values. As the minimum value is almost at the same level, standard deviations are smaller for the cables. The obtained statistical distributions in this paper are of a great importance in considering insulation levels of cable systems.......Statistical distributions of switching overvoltages have been used for decades for the determination of insulation levels of extremely high voltage (EHV) systems. Existing statistical distributions obtained in the 1970s are for overhead lines, and statistical distributions of switching overvoltages...

  15. Life-assessment technique for nuclear power plant cables

    Science.gov (United States)

    Bartoníček, B.; Hnát, V.; Plaček, V.

    1998-06-01

    The condition of polymer-based cable material can be best characterized by measuring elongation at break of its insulating materials. However, it is not often possible to take sufficiently large samples for measurement with the tensile testing machine. The problem has been conveniently solved by utilizing differential scanning calorimetry technique. From the tested cable, several microsamples are taken and the oxidation induction time (OIT) is determined. For each cable which is subject to the assessment of the lifetime, the correlation of OIT with elongation at break and the correlation of elongation at break with the cable service time has to be performed. A reliable assessment of the cable lifetime depends on accuracy of these correlations. Consequently, synergistic effects well known at this time - dose rate effects and effects resulting from the different sequence of applying radiation and elevated temperature must be taken into account.

  16. Arc tracking energy balance for copper and aluminum aeronautic cables

    Science.gov (United States)

    André, T.; Valensi, F.; Teulet, P.; Cressault, Y.; Zink, T.; Caussé, R.

    2017-04-01

    Arc tracking tests have been carried out between two voluntarily damaged aeronautic cables. Copper or aluminum conductors have been exposed to short circuits under alternating current. Various data have been recorded (arc voltage and current, radiated power and ablated mass), enabling to determine a power balance, in which every contribution is estimated. The total power is mainly transferred to the cables (between 50 and 65%, depending on the current and the cable type), and causes the melting and partial vaporization of the metallic core and insulating material, or is conducted or radiated. The other part is deposited into the arc column, being either radiated, convected or conducted.

  17. Extrudate Expansion Modelling through Dimensional Analysis Method

    DEFF Research Database (Denmark)

    A new model framework is proposed to correlate extrudate expansion and extrusion operation parameters for a food extrusion cooking process through dimensional analysis principle, i.e. Buckingham pi theorem. Three dimensionless groups, i.e. energy, water content and temperature, are suggested...... to describe the extrudates expansion. From the three dimensionless groups, an equation with three experimentally determined parameters is derived to express the extrudate expansion. The model is evaluated with whole wheat flour and aquatic feed extrusion experimental data. The average deviations...

  18. Extruded plastic scintillator for MINERvA

    Energy Technology Data Exchange (ETDEWEB)

    Pla-Dalmau, Anna; Bross, Alan D.; /Fermilab; Rykalin, Victor V.; Wood, Brian M.; /NICADD, DeKalb

    2005-11-01

    An extrusion line has recently been installed at Fermilab in collaboration with NICADD (Northern Illinois Center for Accelerator and Detector Development). This new facility will serve to further develop and improve extruded plastic scintillator. Since polystyrene is widely used in the consumer industry, the logical path was to investigate the extrusion of commercial-grade polystyrene pellets with dopants to yield high quality plastic scintillator. The D0 and MINOS experiments are already using extruded scintillator strips in their detectors. A new experiment at Fermilab is pursuing the use of extruded plastic scintillator. A new plastic scintillator strip is being tested and its properties characterized. The initial results are presented here.

  19. TEXTURE ANALYSIS OF EXTRUDED APPLE POMACE - WHEAT SEMOLINA BLENDS

    Directory of Open Access Journals (Sweden)

    Ivan Bakalov

    2016-03-01

    Full Text Available Apple pomace - wheat semolina blends were extruded in a laboratory single screw extruder (Brabender 20 DN, Germany. Effects apple pomace content, moisture content, screw speed, and temperature of final cooking zone on texture of extrudates were studied applying response surface methodology. The texture characteristics of the extrudates were measured using a TA.XT Plus Texture Analyser, Stable Micro Systems.

  20. Experimental Study on Extruded Beer Adjunct Used for Brewing Beer

    Institute of Scientific and Technical Information of China (English)

    SHEN De-chao

    2004-01-01

    The properties of saccharified and boiled worts between extruded and traditional non-extruded beer adjuncts were studied at the laboratory and a small beer brewing equipment( 100 L) in this paper. Test results indicate that the main saccharification indices and filtration speeds of worts between extruded and traditional non-extruded beer adjuncts are similar basically. The collected rate of extracted material of worts of extruded beer adjuncts is 8%more than that of traditional non-extruded beer adjuncts. Fermentation time of worts of extruded beer adjuncts is 10 %less than that of traditional non-extruded beer adjuncts. The energy consumption of extruded beer adjuncts in saccharification process is 13 % less than that of traditional non-extruded beer adjuncts.

  1. Testing of flat conductor cable to Underwriters Laboratory standards UL719 and UL83

    Science.gov (United States)

    Loggins, R. W.; Herndon, R. H.

    1974-01-01

    The flat conductor cable (FCC) which was tested consisted of three AWG No. 12 flat copper conductors laminated between two films of polyethylene terephthalate (Mylar) insulation with a self-extinguishing polyester adhesive. Results of the tests conducted on this cable, according to specifications, warrants the use of this FCC for electrical interconnections in a surface nonmetallic protective covering.

  2. Research of PD on-line Monitoring System for DC Cable

    Directory of Open Access Journals (Sweden)

    Duan Da-Peng

    2014-01-01

    Full Text Available In order to monitor the insulation of XLPE cable of rail system, an On-line Partial Discharge (PD Monitoring System applied for 1500V DC cables of Shanghai Traction Substation is described, including its hardware and software structure. After installed, this system successfully detected one PD signal. The results demonstrated that this system worked stably and reliably.

  3. Towards low energy building using vacuum insulation panels. Advantages and disadvantages

    Directory of Open Access Journals (Sweden)

    Adrian-Alexandru CIOBANU

    2013-12-01

    Full Text Available The increasing interest in building developments with very low energy consumption, energy-positive or passive houses has directed the attention of those involved in this area to high thermal performance insulation materials, like vacuum insulation panels (VIP. Vacuum insulation panels are part of high thermal performance insulations, which attempts to be introduced and used in the construction field. The main interest for these materials is due to their thermal properties, namely to their very low thermal conductivity (of 5 to 8 times compared with traditional thermal insulation materials (mineral wool, extruded/expanded polystyrene. The thermal conductivity of thermal insulation widely used, hence traditional or classical insulation names, as expanded polystyrene (EPS, extruded polystyrene (XPS, mineral wool or polyurethane foam (PUR has typical values between 0.03 and 0.05 W/(mK. Using these types of insulations to fulfill performance envelope elements in terms of energy, leads to the adoption of an increased insulation thickness. Vacuum insulation panels may offer new solution for high performance insulation with a thickness in order of a few centimeters compared to the conventional insulation. Vacuum insulation panels can be used as independently insulation, replacing entirely the conventional ones or as additional insulation.

  4. The surface discharge and breakdown characteristics of HTS DC cable and stop joint box

    Science.gov (United States)

    Kim, W. J.; Kim, H. J.; Cho, J. W.; Kim, S. H.

    2014-09-01

    A high temperature superconducting (HTS) DC cable system consists of a HTS cable and cable joint. The HTS DC cable should be electrically connected in joint boxes because of the unit length of HTS cable is limited to several-hundred meters. In particular, the stop joint box (SJB) must be developed for a compact cooling system. Polypropylene laminated paper (PPLP) and epoxy maybe used as insulating materials for HTS DC cable and SJB. To develop a HTS DC cable, it is necessary to develop the cryogenic insulation technology, materials and the joint methods. In this paper, we will mainly discuss on the DC and impulse characteristics of epoxy and PPLP in liquid nitrogen (LN2). The surface discharge characteristics of epoxy included fillers, PPLP and epoxy with PPLP composite (epoxy + PPLP) were measured under 0.4 MPa. Also, the PPLP-insulated mini-model cable was fabricated and then DC, impulse and DC polarity reversal breakdown strength of mini-model cable under 0.4 MPa were investigated.

  5. Moisture effect on the dielectric response and space charge behaviour of mineral oil impregnated paper insulation

    OpenAIRE

    Hao, Jian; Chen, George; Liao, R

    2011-01-01

    Oil-paper insulation system is widely used in power transformers and cables. Moisture is recognized to the ?enemy number one? for transformer insulation except for temperature [1]. Moisture is not only one of the most important factor which can accelerate the transformer paper insulation aging, but also has great effect on the dielectric properties of oil-paper insulation. In this paper, dielectric response and space charge behaviour of oil-paper insulation sample with three different moistur...

  6. Cable Television for Librarians. Cable Television Primer

    Science.gov (United States)

    Briscoe, Wallace C.

    1973-01-01

    The development of cable television, its present state, and future prospects, including a possible role for libraries, are discussed. (Other conference materials are LI 503071 and 503073 through 503084.) (SJ)

  7. Nuclear power plant cable materials :

    Energy Technology Data Exchange (ETDEWEB)

    Celina, Mathias C.; Gillen, Kenneth T; Lindgren, Eric Richard

    2013-05-01

    A selective literature review was conducted to assess whether currently available accelerated aging and original qualification data could be used to establish operational margins for the continued use of cable insulation and jacketing materials in nuclear power plant environments. The materials are subject to chemical and physical degradation under extended radiationthermal- oxidative conditions. Of particular interest were the circumstances under which existing aging data could be used to predict whether aged materials should pass loss of coolant accident (LOCA) performance requirements. Original LOCA qualification testing usually involved accelerated aging simulations of the 40-year expected ambient aging conditions followed by a LOCA simulation. The accelerated aging simulations were conducted under rapid accelerated aging conditions that did not account for many of the known limitations in accelerated polymer aging and therefore did not correctly simulate actual aging conditions. These highly accelerated aging conditions resulted in insulation materials with mostly inert aging processes as well as jacket materials where oxidative damage dropped quickly away from the air-exposed outside jacket surface. Therefore, for most LOCA performance predictions, testing appears to have relied upon heterogeneous aging behavior with oxidation often limited to the exterior of the cable cross-section a situation which is not comparable with the nearly homogenous oxidative aging that will occur over decades under low dose rate and low temperature plant conditions. The historical aging conditions are therefore insufficient to determine with reasonable confidence the remaining operational margins for these materials. This does not necessarily imply that the existing 40-year-old materials would fail if LOCA conditions occurred, but rather that unambiguous statements about the current aging state and anticipated LOCA performance cannot be provided based on

  8. Cable Tester Box

    Science.gov (United States)

    Lee, Jason H.

    2011-01-01

    Cables are very important electrical devices that carry power and signals across multiple instruments. Any fault in a cable can easily result in a catastrophic outcome. Therefore, verifying that all cables are built to spec is a very important part of Electrical Integration Procedures. Currently, there are two methods used in lab for verifying cable connectivity. (1) Using a Break-Out Box and an ohmmeter this method is time-consuming but effective for custom cables and (2) Commercial Automated Cable Tester Boxes this method is fast, but to test custom cables often requires pre-programmed configuration files, and cables used on spacecraft are often uniquely designed for specific purposes. The idea is to develop a semi-automatic continuity tester that reduces human effort in cable testing, speeds up the electrical integration process, and ensures system safety. The JPL-Cable Tester Box is developed to check every single possible electrical connection in a cable in parallel. This system indicates connectivity through LED (light emitting diode) circuits. Users can choose to test any pin/shell (test node) with a single push of a button, and any other nodes that are shorted to the test node, even if they are in the same connector, will light up with the test node. The JPL-Cable Tester Boxes offers the following advantages: 1. Easy to use: The architecture is simple enough that it only takes 5 minutes for anyone to learn how operate the Cable Tester Box. No pre-programming and calibration are required, since this box only checks continuity. 2. Fast: The cable tester box checks all the possible electrical connections in parallel at a push of a button. If a cable normally takes half an hour to test, using the Cable Tester Box will improve the speed to as little as 60 seconds to complete. 3. Versatile: Multiple cable tester boxes can be used together. As long as all the boxes share the same electrical potential, any number of connectors can be tested together.

  9. Proceedings of the 1993 non-fluorocarbon insulation, refrigeration and air conditioning technology workshop

    Energy Technology Data Exchange (ETDEWEB)

    1994-09-01

    Sessions included: HFC blown polyurethanes, carbon dioxide blown foam and extruded polystyrenes, plastic foam insulations, evacuated panel insulation, refrigeration and air conditioning, absorption and adsorption and stirling cycle refrigeration, innovative cooling technologies, and natural refrigerants. Selected papers have been indexed separately for inclusion in the Energy Science and Technology Database.

  10. Measure Guideline. Installing Rigid Foam Insulation on the Interior of Existing Brick Walls

    Energy Technology Data Exchange (ETDEWEB)

    Natarajan, Hariharan [Consortium for Advanced Residential Buildings (CARB), Norwalk, CT (United States); Klocke, Steve [Consortium for Advanced Residential Buildings (CARB), Norwalk, CT (United States); Puttagunta, Srikanth [Consortium for Advanced Residential Buildings (CARB), Norwalk, CT (United States)

    2012-06-01

    This measure guideline provides information on an effective method to insulate the interior of existing brick masonry walls with extruded polystyrene (XPS) insulation board. The guide outlines step-by-step design and installation procedures while explaining the benefits and tradeoffs where applicable. The authors intend that this document be useful to a varied audience that includes builders,remodelers, contractors and homeowners.

  11. Measure Guideline: Installing Rigid Foam Insulation on the Interior of Existing Brick Walls

    Energy Technology Data Exchange (ETDEWEB)

    Natarajan, H.; Klocke, S.; Puttagunta, S.

    2012-06-01

    This measure guideline provides information on an effective method to insulate the interior of existing brick masonry walls with extruded polystyrene (XPS) insulation board. The guide outlines step-by-step design and installation procedures while explaining the benefits and tradeoffs where applicable. The authors intend that this document be useful to a varied audience that includes builders, remodelers, contractors and homeowners.

  12. Assessment of NDE for key indicators of aging cables in nuclear power plants - Interim status

    Science.gov (United States)

    Glass, S. W.; Ramuhalli, P.; Fifield, L. S.; Prowant, M. S.; Dib, G.; Tedeschi, J. R.; Suter, J. D.; Jones, A. M.; Good, M. S.; Pardini, A. F.; Hartman, T. S.

    2016-02-01

    Degradation of the cable jacket, electrical insulation, and other cable components of installed cables within nuclear power plants (NPPs) is known to occur as a function of age, temperature, radiation, and other environmental factors. System tests verify cable function under normal loads; however, the concern is over cable performance under exceptional loads associated with design-basis events (DBEs). The cable's ability to perform safely over the initial 40-year planned and licensed life has generally been demonstrated and there have been very few age-related cable failures. With greater than 1000 km of power, control, instrumentation, and other cables typically found in an NPP, replacing all the cables would be a severe cost burden. Justification for life extension to 60 and 80 years requires a cable aging management program to justify cable performance under normal operation as well as accident conditions. Currently the gold standard for determining cable insulation degradation is the elongation-at-break (EAB). This, however, is an ex-situ measurement and requires removal of a sample for laboratory investigation. A reliable nondestructive examination (NDE) in-situ approach is desirable to objectively determine the suitability of the cable for service. A variety of tests are available to assess various aspects of electrical and mechanical cable performance, but none of these tests are suitable for all cable configurations nor does any single test confirm all features of interest. Nevertheless, the complete collection of test possibilities offers a powerful range of tools to assure the integrity of critical cables. Licensees and regulators have settled on a practical program to justify continued operation based on condition monitoring of a lead sample set of cables where test data is tracked in a database and the required test data are continually adjusted based on plant and fleet-wide experience. As part of the Light Water Reactor Sustainability program sponsored

  13. The effect of blending polypropylene on the electrical properties of polymeric insulation material Hifax

    Institute of Scientific and Technical Information of China (English)

    常方高

    2004-01-01

    Extensive physical testing has suggested that polymeric material Hifax (Flexible Polypropylene)could be a promising candidate for the next generation of DC insulation. In the work presented in this paper,the DC conductivity and AC breakdown of this polymeric insulation material have been measured as a function of temperature. The results show that Hifax cable insulation has a higher AC breakdown strength than EPR and XLPE (crosslinked polyethylene), and the DC resistivity of Hifax is larger than that of XLPE and oil-impregnated paper insulations. The electrical stress coefficient of resistivity of Hifax wire insulation increases with temperature, which needs to be taken into account in calculating the electrical field distribution across DC cable insulation. It has been observed that there is an anomalous change in resistivity at high electrical field, suggesting charge trapping and detrapping processes are present in Hifax cable insulation. It is concluded that blending Hifax with 62% polypropylene decreases the breakdown strength significantly.

  14. Effect of self-field on the current distribution in Roebel-assembled coated conductor cables

    Science.gov (United States)

    Vojenčiak, M.; Grilli, F.; Terzieva, S.; Goldacker, W.; Kováčová, M.; Kling, A.

    2011-09-01

    Roebel cables are a promising solution for high current, low AC loss cables made of high-temperature superconductors in the form of coated conductors. High current creates significant self-field, which influences the superconductor's current-carrying capability. In this paper, we investigate the influence of the self-field on the cable's critical current and the current repartition among the different strands. In order to investigate the cable's critical current, we analysed the influence of flux creep on the cable properties. Using the experimental material's properties derived from measurements on a single conductor as input for our calculations, we were able to predict the critical current of the cable in two limiting situations: good current sharing and complete electrical insulation among the strands. The results of our calculations show good agreement with the measured critical current of three Roebel cable samples.

  15. Determining Remaining Useful Life of Aging Cables in Nuclear Power Plants – Interim Study FY13

    Energy Technology Data Exchange (ETDEWEB)

    Simmons, Kevin L.; Fifield, Leonard S.; Westman, Matthew P.; Ramuhalli, Pradeep; Pardini, Allan F.; Tedeschi, Jonathan R.; Jones, Anthony M.

    2013-09-27

    The most important criterion for cable performance is its ability to withstand a design-basis accident. With nearly 1000 km of power, control, instrumentation, and other cables typically found in an NPP, it would be a significant undertaking to inspect all of the cables. Degradation of the cable jacket, electrical insulation, and other cable components is a key issue that is likely to affect the ability of the currently installed cables to operate safely and reliably for another 20 to 40 years beyond the initial operating life. The development of one or more nondestructive evaluation (NDE) techniques and supporting models that could assist in determining the remaining life expectancy of cables or their current degradation state would be of significant interest. The ability to nondestructively determine material and electrical properties of cable jackets and insulation without disturbing the cables or connections has been deemed essential. Currently, the only technique accepted by industry to measure cable elasticity (the gold standard for determining cable insulation degradation) is the indentation measurement. All other NDE techniques are used to find flaws in the cable and do not provide information to determine the current health or life expectancy. There is no single NDE technique that can satisfy all of the requirements needed for making a life-expectancy determination, but a wide range of methods have been evaluated for use in NPPs as part of a continuous evaluation program. The commonly used methods are indentation and visual inspection, but these are only suitable for easily accessible cables. Several NDE methodologies using electrical techniques are in use today for flaw detection but there are none that can predict the life of a cable. There are, however, several physical and chemical ptoperty changes in cable insulation as a result of thermal and radiation damage. In principle, these properties may be targets for advanced NDE methods to provide early

  16. Electrical power cable engineering

    CERN Document Server

    Thue, William A

    2011-01-01

    Fully updated, Electrical Power Cable Engineering, Third Edition again concentrates on the remarkably complex design, application, and preparation methods required to terminate and splice cables. This latest addition to the CRC Press Power Engineering series covers cutting-edge methods for design, manufacture, installation, operation, and maintenance of reliable power cable systems. It is based largely on feedback from experienced university lecturers who have taught courses on these very concepts.The book emphasizes methods to optimize vital design and installation of power cables used in the

  17. Radiation-crosslinked polyethylene for wire and cable applications

    Science.gov (United States)

    Ueno, Keiji; Uda, Ikujiro; Tada, Shotaro

    Polyethylene is used as an insulation material for wires and cables because of its excellent electrical properties. Polyethylene is also a typical irradiated crosslinked polymer. The characteristics of irradiated polyethylene, the effects of density, molecular weight and so on, were studied.

  18. 30 CFR 18.35 - Portable (trailing) cables and cords.

    Science.gov (United States)

    2010-07-01

    ... trip setting as near as practicable to the maximum starting-current-inrush value, but the setting shall... conductor of a current-carrying capacity consistent with the Insulated Power Cable Engineers Association (IPCEA) standards. (See Tables 1 and 2 in Appendix I.) (2) Have current-carrying conductors not...

  19. The impact of added insulation on air leakage

    Energy Technology Data Exchange (ETDEWEB)

    Anon

    2002-01-01

    It is relatively easy to calculate the impact on energy consumption when thermal insulation is added to the building envelope. However, other effects such as air leakage through the exterior wall assembly, and the potential for water condensation also have to be considered. By adding insulation to the exterior wall assembly, the temperature gradient of the wall is changed and the risk of condensation is increased, especially if warm, moist indoor air can flow through the wall. The study by Dominique Derome, Paul Fazio and Guylaine Desmarais for the CMHC Research Division, of which this paper is a summary, examined three types of air leakage paths, i.e. long air exfiltration path; concentrated air exfiltration path; and distributed exfiltration path. Experiments involved placing 38 mm rigid extruded polystyrene insulation on the interior side of three wood studs and fiberglass batt insulation wall assemblies, while four other samples had the same 38 mm rigid extruded polystyrene insulation added on the exterior of the assembly over the fiberboard sheathing. Both, warm and cold side additions of rigid foam insulation to the existing assemblies increased thermal performance by 55 per cent. When blown cellulose fibre was used as insulation instead of fibreglass batting, the increase in thermal performance was 66 per cent. Addition of the rigid foam insulation on the warm side tended to increase the effectiveness. For example, moisture content generally did not rise above 25 per cent, whereas it could climb up to 70 per cent when the insulation was added on the cold side.

  20. UtilityTelecom_CABLE2013

    Data.gov (United States)

    Vermont Center for Geographic Information — The VT Cable dataset (CABLE2013) includes lines depicting the extent of Vermont's cable modem broadband system as of 6/30/2013 in addition to those companies who do...

  1. Extruded Soybean Samples for Mechnical Oil Expression

    Institute of Scientific and Technical Information of China (English)

    JiaFu-go; WuFeng-zhi; 等

    1999-01-01

    Soybean is generally recognized as a source of edible and the deoiled meal is seen as a source of protein in animal feed.In recent years.However,more interest has been directed toward using soy meal as a protein souce for human consumption.Extrusion-expelling of soybean provides an opportunity in this direction.The main focus of this study was to maximize the oil recovery from extruded soybean processed using three different kinds of extrudates and processing conditions.These extruded samples were later pressed uniaxially in a specifically designed test-cell and the oil recovery was recorded over time.The effects of process variables,including applied pressure,pressing temperature and sample height,were investigated.Results indicated that over 90% of the available oil could be recovered from pressing of extruded soy samples.The information generated is likedly to be useful in interpreting the effect of precess variables and extruding equipment for pretreatment of soybean for subsequent mechanical oil expression.

  2. Extruded Soybean Samples for Mechnical Oil Expression

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    Soybean is generally recognized as a source of edible and the deoiled meal is seen as a source of protein in animal feed. In recent years. However,more interest has been directed toward using soy meal as a protein souce for human consumption. Extrusion-expelling of soybean provides an opportunity in this direction. The main focus of this study was to maximize the oil recovery from extruded soybean processed using three differ- ent kinds of extrudates and processing conditions. These extruded samples were later pressed uniaxially in a specifically designed test-cell and the oil recovery was recorded over time. The effects of process variables ,in- cluding applied pressure, pressing temperature and sample height, were investigated. Results indicated that over90% of the available oil could be recovered from pressing of extruded soy samples. The information gen- erated is likedly to be useful in interpreting the effect of precess variables and extruding equipment for pre- treatment of soybean for subsequent mechanical oil expression.

  3. Calculation and measurement of space charge in MV-size xxtruded cables systems under load conditions

    NARCIS (Netherlands)

    Morshuis, P.H.F.; Bodega, R.; Fabiani, D.; Montanari, G.C.; Dissado, L.A; Smit, J.J.

    2007-01-01

    A load current in dc high voltage cables results in a temperature drop across the insulation and hence a radial distribution of the insulation conductivity is found. Direct consequence is an accumulation of space charge in the bulk of the nsulation, that may significantly affect its reliability. Thi

  4. Long-term aging and loss-of-coolant accident (LOCA) testing of electrical cables

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, C.F.; Gauthier, G.; Carlin, F. [and others

    1996-10-01

    Experiments were performed to assess the aging degradation and loss-of-coolant accident (LOCA) behavior of electrical cables subjected to long-term aging exposures. Four different cable types were tested in both the U.S. and France: (1) U.S. 2 conductor with ethylene propylene rubber (EPR) insulation and a Hypalon jacket. (2) U.S. 3 conductor with cross-linked polyethylene (XLPE) insulation and a Hypalon jacket. (3) French 3 conductor with EPR insulation and a Hypalon jacket. (4) French coaxial with polyethylene (PE) insulation and a PE jacket. The data represent up to 5 years of simultaneous aging where the cables were exposed to identical aging radiation doses at either 40{degrees}C or 70{degrees}C; however, the dose rate used for the aging irradiation was varied over a wide range (2-100 Gy/hr). Aging was followed by exposure to simulated French LOCA conditions. Several mechanical, electrical, and physical-chemical condition monitoring techniques were used to investigate the degradation behavior of the cables. All the cables, except for the French PE cable, performed acceptably during the aging and LOCA simulations. In general, cable degradation at a given dose was highest for the lowest dose rate, and the amount of degradation decreased as the dose rate was increased.

  5. Frequency domain reflectometry NDE for aging cables in nuclear power plants

    Science.gov (United States)

    Glass, S. W.; Jones, A. M.; Fifield, L. S.; Hartman, T. S.

    2017-02-01

    Degradation of the cable jacket, electrical insulation, and other cable components of installed cables within nuclear power plants (NPPs) is known to occur as a function of age, temperature, radiation, and other environmental factors. Although system tests verify cable function under normal loads, demonstration of some cable's ability to perform under exceptional loads associated with design-basis events is essential to assuring plant integrity. The cable's ability to perform safely over the initial 40-year planned and licensed life has generally been demonstrated and there have been very few age-related cable failures. With greater than 1000 km of power, control, instrumentation, and other cables typically found in an NPP, replacing all the cables would be a severe cost burden. Justification for life extension to 60 and 80 years requires a cable aging management program that includes condition monitoring to justify cable performance under normal operation as well as accident conditions. A variety of tests are available to assess various aspects of electrical and mechanical cable performance, but none are suitable for all cable configurations nor does any single test confirm all features of interest. One particularly promising test that is beginning to be used more and more by utilities is frequency domain reflectometry (FDR). FDR is a nondestructive electrical inspection technique used to detect and localize faults in power and communication system conductors along the length of a cable from a single connection point. FDR detects discontinuities in the electrical impedance that arise due to cable splices or similar changes along the path of the conductor pair. In addition, FDR has the potential to provide sensitivity to insulation degradation by detecting small changes in impedance between the cable conductors being examined. The technique is also sensitive to cable bends, the particular lay of the cable in tray, proximity to other cable, and other factors that

  6. Method and Experience of Equipment Qualification(EQ) for Cable in NPP

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Sunchul; Bhang, Keugjin; Park, Kyungheum [KHNP Central Research Institute, Daejeon (Korea, Republic of)

    2014-05-15

    The performance of cable mainly depends on polymeric insulating materials, since bad insulation of the cable makes a false signal or a short circuit. Polymeric cable materials are usually made up with cross-linked polyethylene (XLPE), ethylene propylene rubber (EPR), silicone rubber (SR), and chlorosulfonated polyethylene (CSPE). The cables should be qualified to last for over 40 years in plant areas exposed to normal and accident environments. This paper introduces not only codes, procedures, and acceptance criteria of the cable qualification test, but also the type testing experience of the EPR insulated cable during testing period. The standards of the qualification for cables are laws, regulatory guidelines, industry standards in order, and the test codes are subdivided depending on the test items. The regulations and guidelines are the Enforcement Regulation and Rules of the Nuclear Safety Law. The industry standards are IEEE 323, and 383. After the completion of the test, the cable quality depends on whether the performance standards meet the acceptance criteria or not. IEEE 383 requires LOCA simulation of both aged and unaged specimens. This study suggests that aged specimens are more susceptible to failure during LOCA testing.

  7. Bab Eshtar Substation 11 kV Feeder Cable. Mosul, Iraq

    Science.gov (United States)

    2006-10-17

    Item Unit QTY U price Total in US$ 3x150mm2 , 11kv , XLPE insulated cable M 10,000 43 430000 Straight outdoor heat shrinkable splice kit for 3x150mm2...11kv, XLPE cable Ea 15 325 4875 Indoor Heat shrinkable termination kit for 3x150mm2, 11kv XLPE cable Ea 9 250 2250 Outdoor Heat shrinkable...termination kit for 3x150mm2, 11kv XLPE cable Ea 5 275 1375 2 Ring-main feeders with cabinet Ea 2 18000 36000 Excavated sand m3 550 30 16500 Fine soil m3 350

  8. Multistrand superconductor cable

    Science.gov (United States)

    Borden, Albert R.

    1985-01-01

    Improved multistrand Rutherford-type superconductor cable is produced by using strands which are preformed, prior to being wound into the cable, so that each strand has a variable cross section, with successive portions having a substantially round cross section, a transitional oval cross section, a rectangular cross section, a transitional oval cross section, a round cross section and so forth, in repetitive cycles along the length of the strand. The cable is wound and flattened so that the portions of rectangular cross section extend across the two flat sides of the cable at the strand angle. The portions of round cross section are bent at the edges of the flattened cable, so as to extend between the two flat sides. The rectangular portions of the strands slide easily over one another, so as to facilitate flexing and bending of the cable, while also minimizing the possibility of causing damage to the strands by such flexing or bending. Moreover, the improved cable substantially maintains its compactness and cross-sectional shape when the cable is flexed or bent.

  9. Screw Extruder for Pellet Injection System

    Directory of Open Access Journals (Sweden)

    Sharadkumar K. Chhantbar

    2014-05-01

    Full Text Available Solid hydrogenic pellets are used as fuel for fusion energy reactor. A technique for continuous production of solid hydrogen and its isotopes by a screw extruder is suggested for the production of an unlimited number of pellets. The idea was developed and patented by PELIN laboratories, Inc. (Canada. A Gifford McMahon cryocooler is used for the generation of solid hydrogenic fluid pellets. Requirements of the pellets is depends upon the energy to be produced by tokamak. This review paper focuses on the model for the screw extruder for solidification of hydrogen ice having high injection reliability.

  10. Thermal insulator

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, R.; Asada, Y.; Matsuo, Y.; Mikoda, M.

    1985-07-16

    A thermal insulator comprises an expanded resin body having embedded therein an evacuated powder insulation portion which consists of fine powder and a container of film-like plastics or a film-like composite of plastics and metal for enclosing the powder. The resin body has been expanded by a Freon gas as a blowing agent. Since a Freon gas has a larger molecular diameter than the constituent gases of air, it is less likely to permeate through the container than air. Thus present invention provides a novel composite insulator which fully utilizes the benefits of vacuum insulation without necessitating a strong and costly material for a vacuum container.

  11. Cellulose Insulation

    Science.gov (United States)

    1980-01-01

    Fire retardant cellulose insulation is produced by shredding old newspapers and treating them with a combination of chemicals. Insulating material is blown into walls and attics to form a fiber layer which blocks the flow of air. All-Weather Insulation's founders asked NASA/UK-TAP to help. They wanted to know what chemicals added to newspaper would produce an insulating material capable of meeting federal specifications. TAP researched the query and furnished extensive information. The information contributed to successful development of the product and helped launch a small business enterprise which is now growing rapidly.

  12. 关节式电分相过电压致线索烧损分析及对策%Caused of Cables Burn-out of The Over-voltages of Articulated Phase Insulator and Prevention Measures

    Institute of Scientific and Technical Information of China (English)

    裴涛

    2011-01-01

    This paper analyses the causes of the over-voltages of articulated phase insulator,it supplies the prevention measures of how to resolve the problems according to the practice work in XiangFan Power Supply Station.%对接触网的关节式电分相出现过电压的原因进行了分析,并结合襄樊供电段现场实际情况,提出了具体的防治对策。

  13. Electrical Aging Phenomena of Power Cables Aged by Switching Impulses

    Institute of Scientific and Technical Information of China (English)

    L.Cao; A.Zanwar; S.Grzybowski

    2013-01-01

    Due to the insufficient information regarding the aging phenomenon of cables caused by switching impulses,we aged 15 kV XLPE and EPR cable samples by 10000 switching impulses in experiments and tested them.Plus in order to compare the aging phenomenon under multi-stress conditions,additional EPR cable samples were aged by rated AC voltage and current with switching impulses superimposed.We used measurements of partial discharge parameters to monitor the cables' conditions during their aging process,and the AC breakdown voltages measurement to evaluate the cables after aging.Moreover,the Fourier transform infrared (FTIR) spectroscopy measurements revealed the changes of insulation materials after aging.The measurement results confirm that the accelerated aging of cable samples had taken place.The impacts of each individual aging factor are shown through the selected measurements and comparison.The study also helps to assess the reliability of the XLPE and EPR cables under similar condition while serving in power systems.

  14. Electrical Model of Balanced AC HTS Power Cable

    Science.gov (United States)

    Zuijderduin, R.; Chevtchenko, O.; Smit, J. J.; Willén, D.; Melnik, I.; Geschiere, A.

    The future electricity grid will be more sustainable and it will have more power transmission and distribution capability with more electrical power added from decentralized sources on distribution level and from wind parks and other large sources on transmission level. More interconnections and more underground transmission and distribution will be put up. Use of high temperature superconducting (HTS) power cables provides solutions to many of the future grid problems caused by these trends. In this paper we present an electrical model of a balanced 6 km-long three phase triaxial HTS power cable for the Dutch project being developed by a consortium of Alliander, Ultera™ and TUD. The cable currents in all three phases are balanced by selecting proper twist pitches and insulation thickness. The paper focuses on determining inductances, capacitances and AC losses of the balanced cable. Using the developed model, we also determine the voltage drop as function of the cable length, the neutral current and the effect of the imbalanced capacitances on the current distribution of the Dutch distribution cable. The model is validated and it can be used for accurate simulation of the electrical behaviour of triaxial HTS cables in electrical grids.

  15. Qualification High Voltage Testing of Short Triax HTS Cables in the Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    James, David Randy [ORNL; Sauers, Isidor [ORNL; Ellis, Alvin R [ORNL; Tuncer, Enis [ORNL; Gouge, Michael J [ORNL; Demko, Jonathan A [ORNL; Duckworth, Robert C [ORNL; Rey, Christopher M [ORNL

    2009-01-01

    In order to qualify the electrical insulation design of future HTS cables installed in the electric grid, a number of high voltage qualification tests are generally performed in the laboratory on either single-phase model cables and/or actual three-phase cable samples. Prior to installation of the 200-m Triax HTS cable at the American Electric Power Bixby substation near Columbus, Ohio, in September, 2006, such tests were conducted on both single-phase model cables made at ORNL and tri-axial cable sections cut off from cable made on a production run. The three-phase tri-axial design provides some specific testing challenges since the ground shield and three phases are concentric about a central former with each phase separated by dielectric tape insulation immersed in liquid nitrogen. The samples were successfully tested and qualified for partial discharge inception, AC withstand, and lightning impulse where voltage is applied to one phase with the other phases grounded. In addition one of the phase pairs was tested for dc withstand as a ldquoworst caserdquo scenario to simulate the effect of VLF (Very Low Frequency) tests on the actual cable installed at the Bixby site. The model and prototype cables will be described and the high voltage test results summarized.

  16. Optimization of power cable thermal performance using finite-element generated gradient

    Energy Technology Data Exchange (ETDEWEB)

    Al-Saud, M.S.; El-Kady, M.A.; Findlay, R.D. [McMaster Univ., Hamilton, ON (Canada). Dept. of Electrical and Computer Engineering

    2007-07-01

    This paper addressed the issue of optimizing the performance of underground power cables used in modern power transmission and distribution grids. The objective was to reduce operating cost through optimized cable performance under a range of loading conditions, soil parameters and ambient conditions. The thermal performance of an underground cable depends on its design, operation and environmental parameters. The cable ampacity is influenced by cable insulation and structure; thermal conductivity of the surrounding soil; ambient temperature and cable loading. This paper proposed a new method for calculating cable thermal field and ampacity using a concept of perturbed finite element which involves the use of derived sensitivity coefficients associated with different cable parameters. The model provides the optimal solution subject to user-defined constraints. The design problem of choosing the optimal parameter values of the thermal circuit parameters, including the thermal conductivities, boundary conditions and heat generation, was formulated using a multi-dimensional gradient optimization method. The technique takes into account all thermal circuit parameters. The model represents a generalization of the nonlinear programming formulation to include practical cases of the cable design objective functions which may include the thermal parameters and the cable temperatures (ampacity) subjected to upper and lower bounds on the design parameters, linear system of equations constrains, or nonlinear constrains. In order to obtain a reliable cable design, this optimization analysis included the ampacity sensitivity profiles of the soil temperature fluctuations with respect to the thermal circuit parameters. 9 refs., 9 figs.

  17. A correlation for heat transfer coefficients in food extruders.

    Science.gov (United States)

    Levine, L; Rockwood, J

    1986-06-01

    A dimensionless correlation of heat transfer coefficient for heat flow between the extruder barrel wall and extrudate is presented. The standard error of estimate of the correlation is 12.4%. The correlation is useful for the design and scale-up of food extruders and the design of associated temperature control systems.

  18. Properties of extruded teff-oat composites

    Science.gov (United States)

    Teff is an ancient grain that is becoming more popular since it is gluten-free and a good source of vitamins, minerals and protein. Relatively little is known about the properties of extruded teff, although the high insoluble fiber and protein contents have been shown to limit expansion. The health ...

  19. RHEOLOGY OF EXTRUDED WHEY PROTEIN ISOLATE

    Science.gov (United States)

    Whey protein isolate (WPI), a high-quality protein used to fortify a number of foods, may be texturized with a twin-screw extruder. Since extrusion of food is commonly performed above 70°C, which causes whey protein to denature, cold extrusion below 70°C was investigated to determine the effects on...

  20. A phenomenological study on twin screw extruders

    NARCIS (Netherlands)

    Janssen, L.P.B.M.

    1976-01-01

    Although more and more twin screw extruders are being used in the polymer industry, the theoretical background is relatively undeveloped. The literature abounds in contradictions and often informs the reader that all extrusion problems can be solved if a certain new design is considered. The develop

  1. Cable Television; A Bibliographic Review.

    Science.gov (United States)

    Schoenung, James

    This bibliographic review of publications in the field of cable television begins with an introduction to cable television and an outline of the history and development of cable television. Particular attention is given to the regulatory activities of the Federal Communications Commission and the unfulfilled potential of cable television. The…

  2. INFLUENCE OF CONSTRUCTIVE AND TECHNOLOGICAL DEFECTS ON COAXIAL RADIO-FREQUENCY CABLE IMPEDANCE

    Directory of Open Access Journals (Sweden)

    G.V. Bezprozvannych

    2013-04-01

    Full Text Available Coaxial user's radio-frequency cables belong to a category of cable television network elements parameters of which essentially specify the system capabilities as a whole. The cable working frequency spectrum spreading to 1000 MHz along with digital television and soundtrack signals transmission and high-definition television introduction causes more rigid requirements for wave impedance and, consequently, for the cable design. The established norms on user's cable impedance deviations fail to answer the state-of-the-art requirements for granting a complex of interactive services. On the basis of calculations performed, values of internal and external conductor diameters deviations as well as dielectric permeability of the insulation material are validated. For up-to-date user's radio-frequency cables, the impedance deviation from the normalized average value of 75 Ohm should not exceed ± 2 Ohm.

  3. Reusable Hot-Wire Cable Cutter

    Science.gov (United States)

    Pauken, Michael T.; Steinkraus, Joel M.

    2010-01-01

    During the early development stage of balloon deployment systems for missions, nichrome wire cable cutters were often used in place of pyro-actuated cutters. Typically, a nichrome wire is wrapped around a bundle of polymer cables with a low melting point and connected to a relay-actuated electric circuit. The heat from the nichrome reduces the strength of the cable bundle, which quickly breaks under a mechanical load and can thus be used as a release mechanism for a deployment system. However, the use of hand-made heated nichrome wire for cutters is not very reliable. Often, the wrapped nichrome wire does not cut through the cable because it either pulls away from its power source or does not stay in contact with the cable being cut. Because nichrome is not readily soldered to copper wire, unreliable mechanical crimps are often made to connect the nichrome to an electric circuit. A self-contained device that is reusable and reliable was developed to sever cables for device release or deployment. The nichrome wire in this new device is housed within an enclosure to prevent it from being damaged by handling. The electric power leads are internally connected within the unit to the nichrome wire using a screw terminal connection. A bayonet plug, a quick and secure method of connecting the cutter to the power source, is used to connect the cutter to the power leads similar to those used in pyro-cutter devices. A small ceramic tube [0.25-in. wide 0.5-in. long (.6.4-mm wide 13-mm long)] houses a spiraled nichrome wire that is heated when a cable release action is required. The wire is formed into a spiral coil by wrapping it around a mandrel. It is then laid inside the ceramic tube so that it fits closely to the inner surface of the tube. The ceramic tube provides some thermal and electrical insulation so that most of the heat generated by the wire is directed toward the cable bundle in the center of the spiral. The ceramic tube is cemented into an aluminum block, which

  4. Sixty-four-Channel Inline Cable Tester

    Science.gov (United States)

    2008-01-01

    Faults in wiring are a serious concern for the aerospace and aeronautics (commercial, military, and civil) industries. A number of accidents have occurred because faulty wiring created shorts or opens that resulted in the loss of control of the aircraft or because arcing led to fires and explosions. Some of these accidents have resulted in the massive loss of lives (such as in the TWA Flight 800 accident). Circuits on the Space Shuttle have also failed because of faulty insulation on wiring. STS-93 lost power when a primary power circuit in one engine failed and a second engine had a backup power circuit fault. Cables are usually tested on the ground after the crew reports a fault encountered during flight. Often such failures result from vibration and cannot be replicated while the aircraft is stationary. It is therefore important to monitor faults while the aircraft is in operation, when cables are more likely to fail. Work is in progress to develop a cable fault tester capable of monitoring up to 64 individual wires simultaneously. Faults can be monitored either inline or offline. In the inline mode of operation, the monitoring is performed without disturbing the normal operation of the wires under test. That is, the operations are performed unintrusively and are essentially undetectable for the test signal levels are below the noise floor. A cable can be monitored several times per second in the offline mode and once a second in the inline mode. The 64-channel inline cable tester not only detects the occurrence of a fault, but also determines the type of fault (short/open) and the location of the fault. This will enable the detection of intermittent faults that can be repaired before they become serious problems.

  5. Mitigation of Manhole Events Caused by Secondary Cable Failure

    Science.gov (United States)

    Zhang, Lili

    "Manhole event" refers to a range of phenomena, such as smokers, fires and explosions which occur on underground electrical infrastructure, primarily in major cities. The most common cause of manhole events is decomposition of secondary cable initiated by an electric fault. The work presented in this thesis addresses various aspects related to the evolution and mitigation of the manhole events caused by secondary cable insulation failure. Manhole events develop as a result of thermal decomposition of organic materials present in the cable duct and manholes. Polymer characterization techniques are applied to intensively study the materials properties as related to manhole events, mainly the thermal decomposition behaviors of the polymers present in the cable duct. Though evolved gas analysis, the combustible gases have been quantitatively identified. Based on analysis and knowledge of field conditions, manhole events is divided into at least two classes, those in which exothermic chemical reactions dominate and those in which electrical energy dominates. The more common form of manhole event is driven by air flow down the duct. Numerical modeling of smolder propagation in the cable duct demonstrated that limiting air flow is effective in reducing the generation rate of combustible gas, in other words, limiting manhole events to relatively minor "smokers". Besides manhole events, another by-product of secondary cable insulation breakdown is stray voltage. The danger to personnel due to stray voltage is mostly caused by the 'step potential'. The amplitude of step potential as a result of various types of insulation defects is calculated using Finite Element Analysis (FEA) program.

  6. Dissipationless conductance in a topological coaxial cable

    Science.gov (United States)

    Schuster, Thomas; Iadecola, Thomas; Chamon, Claudio; Jackiw, Roman; Pi, So-Young

    2016-09-01

    We present a dynamical mechanism leading to dissipationless conductance, whose quantized value is controllable in a (3+1)-dimensional electronic system. The mechanism is exemplified by a theory of Weyl fermions coupled to a Higgs field, also known as an axion insulator. We show that the insertion of an axial gauge flux can induce vortex lines in the Higgs field, similar to the development of vortices in a superconductor upon the insertion of magnetic flux. We further show that the necessary axial gauge flux can be generated using Rashba spin-orbit coupling or a magnetic field. Vortex lines in the Higgs field are known to bind chiral fermionic modes, each of which serves as a one-way channel for electric charge with conductance e2/h . Combining these elements, we present a physical picture, the "topological coaxial cable," illustrating how the value of the quantized conductance could be controlled in such an axion insulator.

  7. Dissipationless conductance in a topological coaxial cable

    CERN Document Server

    Schuster, Thomas; Chamon, Claudio; Jackiw, Roman; Pi, So-Young

    2016-01-01

    We present a dynamical mechanism leading to dissipationless conductance, whose quantized value is controllable, in a (3+1)-dimensional electronic system. The mechanism is exemplified by a theory of Weyl fermions coupled to a Higgs field--also known as an axion insulator. We show that the insertion of an axial gauge flux can induce vortex lines in the Higgs field, similarly to the development of vortices in a superconductor upon the insertion of magnetic flux. We further show that the necessary axial gauge flux can be generated using Rashba spin-orbit coupling or a magnetic field. Vortex lines in the Higgs field are known to bind chiral fermionic modes, each of which serves as a one-way channel for electric charge with conductance $e^2/h$. Combining these elements, we present a physical picture, the "topological coaxial cable," illustrating how the value of the quantized conductance could be controlled in such an axion insulator.

  8. Lifetime assessment by intermittent inspection under the mixture Weibull power law model with application to XLPE cables.

    Science.gov (United States)

    Hirose, H

    1997-01-01

    This paper proposes a new treatment for electrical insulation degradation. Some types of insulation which have been used under various circumstances are considered to degrade at various rates in accordance with their stress circumstances. The cross-linked polyethylene (XLPE) insulated cables inspected by major Japanese electric companies clearly indicate such phenomena. By assuming that the inspected specimen is sampled from one of the clustered groups, a mixed degradation model can be constructed. Since the degradation of the insulation under common circumstances is considered to follow a Weibull distribution, a mixture model and a Weibull power law can be combined. This is called The mixture Weibull power law model. By using the maximum likelihood estimation for the newly proposed model to Japanese 22 and 33 kV insulation class cables, they are clustered into a certain number of groups by using the AIC and the generalized likelihood ratio test method. The reliability of the cables at specified years are assessed.

  9. Robotic Arm Biobarrier Cable

    Science.gov (United States)

    2008-01-01

    This image, taken by the Surface Stereo Imager on NASA's Phoenix Mars Lander on the 14th Martian day of the mission (June 7, 2008), shows the cable that held the Robotic Arm's biobarrier in place during flight has snapped. The cable's springs retracted to release the biobarrier right after landing. To the lower right of the image a spring is visible. Extending from that spring is a length of cable that snapped during the biobarrier's release. A second spring separated from the cable when it snapped and has been photographed on the ground under the lander near one of the legs. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  10. Robotic Arm Biobarrier Cable

    Science.gov (United States)

    2008-01-01

    This image, taken by the Surface Stereo Imager on NASA's Phoenix Mars Lander on the 14th Martian day of the mission (June 7, 2008), shows the cable that held the Robotic Arm's biobarrier in place during flight has snapped. The cable's springs retracted to release the biobarrier right after landing. To the lower right of the image a spring is visible. Extending from that spring is a length of cable that snapped during the biobarrier's release. A second spring separated from the cable when it snapped and has been photographed on the ground under the lander near one of the legs. The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  11. Buoyant Cable Antenna System

    Science.gov (United States)

    2008-07-02

    comprise a mechanical jacket surrounding a hollow core enclosing the seismic sensor and signal transfer means. Elongated axial stress elements for...to S. H. Bittleston, discloses a semi-dry marine seismic streamer cable that consists of a number of connected streamer cable sections which each...transmitting axial loads and a radial reinforcement member for relieving radial loads are provided in the jacket . The core is filled with a fluid or fluid

  12. Modeling of cable vibration effects of cable-stayed bridges

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The analysis of dynamic responses of cable-stayed bridges subjected to wind and earthquake loads generallyconsiders only the motions of the bridge deck and pylons. The influence of the stay cable vibration on the responses of the bridgeis either ignored or considered by approximate procedures. The transverse vibration of the stay cables, which can be significant insome cases, are usually neglected in previous research. In the present study, a new three-node cable element has been developed tomodel the transverse motions of the cables. The interactions between the cable behavior and the other parts of the bridgesuperstructure are considered by the concept of dynamic stiffness. The nonlinear effect of the cable caused by its self-weight isincluded in the formulation. Numerical examples are presented to demonstrate the accuracy and efficiency of the proposed model.The impact of cable vibration behavior on the dynamic characteristics of cable-stayed bridges is discussed.

  13. Electron spin resonance spectral study of PVC and XLPE insulation materials and their life time analysis

    Science.gov (United States)

    Morsy, M. A.; Shwehdi, M. H.

    2006-03-01

    Electron spin resonance (ESR) study is carried out to characterize thermal endurance of insulating materials used in power cable industry. The presented work provides ESR investigation and evaluation of widely used cable insulation materials, namely polyvinyl chloride (PVC) and cross-linked polyethylene (XLPE). The results confirm the fact that PVC is rapidly degrades than XLPE. The study also indicates that colorants and cable's manufacturing processes enhance the thermal resistance of the PVC. It also verifies the powerfulness and the importance of the ESR-testing of insulation materials compared to other tests assumed by International Electrotechnical Commission (IEC) Standard 216-procedure, e.g. weight loss (WL), electric strength (ES) or tensile strength (TS). The estimated thermal endurance parameters by ESR-method show that the other standard methods overestimate these parameters and produce less accurate thermal life time curves of cable insulation materials.

  14. Aerodynamic stability of cable-supported bridges using CFRP cables

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xin-jun; YING Lei-dong

    2007-01-01

    To gain understanding of the applicability of carbon fiber reinforced polymer (CFRP) cable in cable-supported bridges, based on the Runyang Bridge and Jinsha Bridge, a suspension bridge using CFRP cables and a cable-stayed bridge using CFRP stay cables are designed, in which the cable's cross-sectional area is determined by the principle of equivalent axial stiffness.Numerical investigations on the aerodynamic stability of the two bridges are conducted by 3D nonlinear aerodynamic stability analysis. The results showed that as CFRP cables are used in cable-supported bridges, for suspension bridge, its aerodynamic stability is superior to that of the case using steel cables due to the great increase of the torsional frequency; for cable-stayed bridge,its aerodynamic stability is basically the same as that of the case using steel stay cables. Therefore as far as the wind stability is considered, the use of CFRP cables in cable-supported bridges is feasible, and the cable's cross-sectional area should be determined by the principle of equivalent axial stiffness.

  15. SSME Electrical Harness and Cable Development and Evolution

    Science.gov (United States)

    Abrams, Russ; Heflin, Johnny; Burns, Bob; Camper, Scott J.; Hill, Arthur J.

    2010-01-01

    The Space Shuttle Main Engine (SSME) electrical harness and cable system consists of the various interconnecting devices necessary for operation of complex rocket engine functions. Thirty seven harnesses incorporate unique connectors, backshell adapters, conductors, insulation, shielding, and physical barriers for a long maintenance-free life while providing the means to satisfy performance requirements and to mitigate adverse environmental influences. The objective of this paper is to provide a description of the SSME electrical harness and cable designs as well as the development history and lessons learned.

  16. AC Cable: Yokohama Project

    Science.gov (United States)

    Masuda, Takato

    High Temperature Superconducting (HTS) cables can transmit large amounts of electricity in a compact size with minimal losses. Therefore, they are expected to save the construction cost of underground lines in urban areas and decrease transmission losses. Several HTS cables have recently been demonstrated in networks around the world, and full-scale commercialization is expected in the near future. In Japan, the development of compact HTS cables suitable for urban deployment has been underway since the early 1990s. In 2007, a national project was started to verify their operational performance and long-term reliability in the grid. An HTS cable 240 m long was installed at the Asahi substation of the Tokyo Electric Power Company (TEPCO) in Yokohama; then a joint, terminations and cooling system was constructed in 2011. After successful performance tests, the cable was connected to the grid for the first time in Japan, and started to deliver electricity to 70,000 households in October 2012. This trouble-free in-grid service continued for over a year. We can conclude that the HTS cable system performs well and has the stability required for long-term in-grid operations.

  17. 30 CFR 77.605 - Breaking trailing cable and power cable connections.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Breaking trailing cable and power cable... OF UNDERGROUND COAL MINES Trailing Cables § 77.605 Breaking trailing cable and power cable connections. Trailing cable and power cable connections between cables and to power sources shall not be...

  18. Analysis of Extruded Polystyrene Short-Term Compression Dependence on Exposure Time

    Directory of Open Access Journals (Sweden)

    Saulius VAITKUS

    2013-12-01

    Full Text Available Extruded polystyrene is extensively used in many applications such as thermal insulation, packaging, structural use and buoyancy. In order to an effective use of this material it is essential to know its behavior under compression. The research in this work was carried out by using extruded polystyrene boards (F200, F300, F400, F500 and F700 which were produced by Lithuanian and Finland manufacturers. The changes of extruded polystyrene ultimate compressive stress σcr, ultimate strain, initial modulus of elasticity and thickness were determined right away after production and after a certain exposure time of specimens. It was noticed significant changes in strength characteristics after 45 days. Compression tests and conditioning of specimens were conducted at 23 °C ±2 °C ambient temperature and 50 % ±5 % relative humidity. Regression dependences of ultimate compressive stress σcr and ultimate strain on exposure time (from 10 to 326 days were presented. DOI: http://dx.doi.org/10.5755/j01.ms.19.4.2582

  19. Design and Evaluation of 275 kV-3 kA HTS Power Cable

    Science.gov (United States)

    Yagi, M.; Mukoyama, S.; Mitsuhashi, T.; Jun, T.; Liu, J.; Nakayama, R.; Hayakawa, N.; Wang, X.; Ishiyama, A.; Amemiya, N.; Hasegawa, T.; Saitoh, T.; Ohkuma, T.; Maruyama, O.

    A 275 kV 3 kA high temperature superconducting (HTS) cable has been developed in the Materials & Power Applications of Coated Conductors (M-PACC) project. The cable is expected to be put to practical use as the backbone power line in the future because the capacity of 1.5 GW is about the same as overhead transmission lines. The 30 m cable has been designed on the basis of design values that had been obtained by various voltage tests, AC loss measurement tests, short circuit tests, and other elementary tests. Cable insulation was determined by the design stresses and test conditions based on IEC, JEC (Japan electrical standards), and other HTS demonstrations. This cable was also designed to withstand the short circuit test of 63 kA for 0.6 seconds and to have low losses, including AC loss and dielectric loss of 0.8 W/m at 3kA, 275 kV. Based on the design, a 30 m cable was manufactured, and short samples during this manufacturing process were confirmed to have the designed characteristics. Furukawa Electric prepared a demonstration of the 30 m cable with two terminations and a cable joint. The long-term test under a current of 3 kA, and test voltage determined from 30 years of insulation degradation has been conducted since November 2012 at Shenyang in China.

  20. Interface Properties in Extruded FRC-Materials

    DEFF Research Database (Denmark)

    Stang, Henrik

    1997-01-01

    In a research and development project recently carried out at Department of Structural Engineering and Materials, Technical University of Denmark a new extrusion process for HPFRCC-materials was demonstrated.It is shown that superior interfacial properties are obtained in a polypropylene fiber...... reinforced cementitious material extruded by the developed process. It is further more shown that the fiber-matrix bond is highly dependent on the relative slip at the interface and a bond-slip relationship is suggested for the extruded material. The observed very high fiber-matrix bond is explained...... by the densification of the interfacial matrix material which has taken place during the consolidation process and which can be observed in the thin-section analysis....

  1. Description of Extrudate Swell for Polymer Nanocomposites

    Directory of Open Access Journals (Sweden)

    Kejian Wang

    2010-01-01

    Full Text Available Extrudate swell is often observed to be weakened in nanocomposites compared to the pure polymer matrix. A theory quantifying this would be significant either for optimum processing or for understanding their viscoelasticity. A unified extrudate swell correlation with material properties and capillary parameters was suggested for polymer melt and their nanocomposites when considering the reservoir entry effect. More importantly, it was the first to find that the composite swell ratio can be the matrix swell ratio multiplied by the concentration shift factor, which is similar to the dynamic moduli expression for composites. The factor is a function of the shear field (stress or shear rate, filler content, filler internal structure and the surface state as well as the matrix properties. Several sets of swell data for nanocomposites were chosen from publications to test the new theories. The proposed quantitative model displayed good fit for the five kinds of nanocomposites, which verified the rationality of the swell theory for nanocomposites.

  2. Evaluation of the radiation resistance of electrical insulation materials

    Science.gov (United States)

    Perrin, Sh.; Schönbacher, H.; Tavlet, M.; Widler, R.

    2002-12-01

    The qualification of insulating materials for electrical cables is often accomplished according to the IEC 60544 standard of the International Electrotechnical Commission. The mechanical properties of the polymeric insulators are tested prior and after irradiation at relatively high dose rates. To assess the ageing of selected materials under realistic service conditions, usually at lower dose rate, an IEC Working Group has proposed extrapolation methods (IEC 61244-2), one of which is applied here for a cable sheathing material from Huber+Suhner. The method is found to be suitable to compare radiation resistance data of different materials irradiated under different conditions.

  3. Research on influence of high-voltage cable un-homogeneities on process of short waves distribution

    Energy Technology Data Exchange (ETDEWEB)

    Tirsu, M.; Berzan, V.; Rimschi, V. [Power Engineering Institute of Academy of Sciences of Moldova, 5 Academy Street, Kishinev (Moldova); Postolache, P. [University ' ' Politechnics' ' of Bucharest, Street Splaiul Independentei 313, Bucharest (Romania)

    2008-12-15

    The partial discharges (PDs) inside of high-voltage cable insulation negatively influence cable service lifespan. Therefore timely detection and localization of affected areas with the weakened electric insulation is a vital question, in particular - according to measured values of PD parameters before they reach the dangerous stage of their development. Electrical cable is a circuit with the distributed parameters for current and voltage waves, initiated by local PD which changes their starting values with time. These changes can be taken as informative parameters for solving problems of localization of the defect and evaluation of dangers to cable's performance. Clear and detailed understanding of PD pulse distribution features in power cables is the basis for correctly solving cable diagnostics tasks with non-destructive approaches. This article uses the mathematical model of a power cable on the premises of cable equations. The model allows for modeling of wave processes in a non-uniform electric circuit (at sudden change of longitudinal parameters) in view of repeated reflection of PD waves from the ends and un-homogeneities of an electric cable. Results of mathematical modeling were compared to the data received from physical model of 110 kV XLPE electric cable. The cable physical model is realized with the help of the chained circuit consisting of 15 quad-poles. This document shows results of measurements and modeling of wave process caused by PD. Also, details of the wave process as dependent on time and frequency, and practical use of measurements of PD for cable insulation control, are discussed. Practical measurements show high degree of accuracy with regards to the data generated by theoretical model analysis. (author)

  4. Cable-Dispensing Cart

    Science.gov (United States)

    Bredberg, Alan S.

    2003-01-01

    A versatile cable-dispensing cart can support as many as a few dozen reels of cable, wire, and/or rope. The cart can be adjusted to accommodate reels of various diameters and widths, and can be expanded, contracted, or otherwise reconfigured by use of easily installable and removable parts that can be carried onboard. Among these parts are dispensing rods and a cable guide that enables dispensing of cables without affecting the direction of pull. Individual reels can be mounted on or removed from the cart without affecting the other reels: this feature facilitates the replacement or reuse of partially depleted reels, thereby helping to reduce waste. Multiple cables, wires, or ropes can be dispensed simultaneously. For maneuverability, the cart is mounted on three wheels. Once it has been positioned, the cart is supported by rubber mounts for stability and for prevention of sliding or rolling during dispensing operations. The stability and safety of the cart are enhanced by a low-center-of-gravity design. The cart can readily be disassembled into smaller units for storage or shipping, then reassembled in the desired configuration at a job site.

  5. 77 FR 19525 - Specification for 15 kV and 25 kV Primary Underground Power Cable

    Science.gov (United States)

    2012-04-02

    ..., the insulation shield materials are not XLPE but are in fact a co- polymer material. Polymeric layer... Polyethylene Plastics Extrusion Materials for Wire and Cable (ASTM D 1248-05), approved March 1, 2005... polyethylene (TR-XLPE) insulation compound containing an additive, a polymer modification filler, which...

  6. Mathematical Model for Thermal Processes of Single-Core Power Cable

    Directory of Open Access Journals (Sweden)

    D. Zalizny

    2012-01-01

    Full Text Available The paper proposes a mathematical model for thermal processes that permits to calculate non-stationary thermal processes of core insulation and surface of a single-core power cable in real-time mode. The model presents the cable as four thermal homogeneous bodies: core, basic insulation, protective sheath and internal environment. Thermal processes between homogeneous bodies are described by a system of four differential equations. The paper contains a proposal to solve this system of equations with the help of a thermal equivalent circuit and the Laplace transform. All design ratios for thermal parameters and algorithm for calculating temperature of core insulation and temperature of power cable surface. These algorithms can be added in the software of microprocessor devices. The paper contains results of experimental investigations and reveals that an absolute error of the mathematical model does not exceed 3ºС.

  7. Ceramic end seal design for high temperature high voltage nuclear instrumentation cables

    Science.gov (United States)

    Meiss, James D.; Cannon, Collins P.

    1979-01-01

    A coaxial, hermetically sealed end structure is described for electrical instrumentation cables. A generally tubular ceramic body is hermetically sealed within a tubular sheath which is in turn sealed to the cable sheath. One end of the elongated tubular ceramic insulator is sealed to a metal end cap. The other end of the elongated tubular insulator has an end surface which is shaped concave relative to a central conductor which extends out of this end surface. When the end seal is hermetically sealed to an instrumentation cable device and the central conductor is maintained at a high positive potential relative to the tubular metal sheath, the electric field between the central conductor and the outer sheath tends to collect electrons from the concave end surface of the insulator. This minimizes breakdown pulse noise generation when instrumentation potentials are applied to the central conductor.

  8. Heat Transfer Study for HTS Power Transfer Cables

    Science.gov (United States)

    Augustynowicz, S.; Fesmire, J.

    2002-01-01

    Thermal losses are a key factor in the successful application of high temperature superconducting (HTS) power cables. Existing concepts and prototypes rely on the use of multilayer insulation (MLI) systems that are subject to large variations in actual performance. The small space available for the thermal insulation materials makes the application even more difficult because of bending considerations, mechanical loading, and the arrangement between the inner and outer piping. Each of these mechanical variables affects the heat leak rate. These factors of bending and spacing are examined in this study. Furthermore, a maintenance-free insulation system (high vacuum level for 20 years or longer) is a practical requirement. A thermal insulation system simulating a section of a flexible FITS power cable was constructed for test and evaluation on a research cryostat. This paper gives experimental data for the comparison of ideal MLI, MLI on rigid piping, and MLI between flexible piping. A section of insulated flexible piping was tested under cryogenic vacuum conditions including simulated bending and spacers.

  9. The Basic Properties of PPLP for HTS DC Cable

    Science.gov (United States)

    Kim, W. J.; Kim, H. J.; Cho, J. W.; Kim, S. H.

    In order to develop high temperature superconducting (HTS) DC cable, it is important to understand the cooling system, high voltage insulation and materials at cryogenic temperature. Especially, the basic properties of insulating materials must be solved for the long life, reliability and compact of system. In this paper, we will discuss mainly on the electrical and the mechanical properties of polypropylene laminated paper (PPLP) in liquid nitrogen (LN2). The polarity effect of DC and impulse voltage, the volume resistivity and the space charge distribution and frost were studied. Furthermore, the mechanical properties such as tensile strength of PPLP at LN2 (77 K) and room temperature (300 K) were studied.

  10. The Design of Partial Discharge On-Line Monitoring System for XLPE Power Cable

    OpenAIRE

    Chen Rui-Long; Qian Yong; Ye Hai-Feng; Sheng Ge-Hao; Jiang Xiu-Chen

    2013-01-01

    Partial discharge detection is an important means to assess the situation of XLPE power cable’s insulation. This study has developed an on-line monitoring system which applies to the medium voltage XLPE cable on partial discharge, described its working principle, components of hardware, software designing and program implementation in details. Through monitoring the partial discharge signal in grounding lines of the XLPE cable’s shield, the system integrated assess the situation of XLPE cable...

  11. VT Cable Modem Systems 2013

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) The VT Cable Modem dataset (CABLEMOD2013) includes lines depicting the extent of Vermont's cable modem broadband system as of 6/30/2013. This data...

  12. VT Cable Modem Systems 2005

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) The VT Cable Modem dataset (CABLEMOD2005) includes lines depicting the extent of Vermont's cable modem broadband system as of 12/31/2005. This...

  13. Cable historical operating temperature estimator

    Energy Technology Data Exchange (ETDEWEB)

    Leon de, F.; St-Roch, P.; Beauregard, C. [Cyme International, St-Bruno, PQ (Canada)

    2006-07-01

    A tool designed to accurately determine the thermal age of underground cables was described. The cable historical operating temperature estimate (CHOTE) is a software application designed to identify which cables have exceeded their normal and emergency operating temperatures. CHOTE is also capable of predicting when cables are likely to reach their maximum design temperature in the future. The system operates by processing archived loading information from data acquisition systems in order to automatically analyze all the thermal sections of a system. Cables that exceed their emergency and normal temperatures for the longest amount of time are ranked first, and outputs display when and where the hot spots have occurred. CHOTE is also able to study the impact of the addition of new cables and to determine the remaining ampacity of cables installed in a given duct bank. It was concluded that the CHOTE system can help in the efficient management of cable repairs and installations. 28 refs., 7 figs.

  14. Space Flight Cable Model Development

    Science.gov (United States)

    Spak, Kaitlin

    2013-01-01

    This work concentrates the modeling efforts presented in last year's VSGC conference paper, "Model Development for Cable-Harnessed Beams." The focus is narrowed to modeling of space-flight cables only, as a reliable damped cable model is not yet readily available and is necessary to continue modeling cable-harnessed space structures. New experimental data is presented, eliminating the low-frequency noise that plagued the first year's efforts. The distributed transfer function method is applied to a single section of space flight cable for Euler-Bernoulli and shear beams. The work presented here will be developed into a damped cable model that can be incorporated into an interconnected beam-cable system. The overall goal of this work is to accurately predict natural frequencies and modal damping ratios for cabled space structures.

  15. New Insulation Application Process for Wind-And Magnet Fabrication

    Science.gov (United States)

    Kano, K. S.; Stewart, M. W.; Hooker, M. W.

    2008-03-01

    Wind-and-react processes offer a cost-effective means of fabricating large-scale Nb3Sn magnets, while also eliminating the need to manipulate the brittle superconductor after the high-temperature reaction process. Composite Technology Development, Inc. (CTD) has developed a hybrid inorganic/organic insulation system that can be co-processed with the Nb3Sn magnet at elevated temperatures. In this work, a new process was demonstrated for applying a thin, ceramic-based insulation that is compatible with wind-and-react processing. The insulation was applied to Rutherford cables using a continuous manufacturing process, and cable assemblies (i.e., 10-stacks) were fabricated and tested. The results of this work show that the insulation possesses a high strain tolerance, as well as the dielectric strength and fatigue resistance needed for high-field magnet applications.

  16. Direct compression properties of melt-extruded isomalt.

    Science.gov (United States)

    Ndindayino, F; Henrist, D; Kiekens, F; Van den Mooter, G; Vervaet, C; Remon, J P

    2002-03-20

    Isomalt, a sugar alcohol, was melt-extruded prior to compression in order to improve its tabletting properties. After fusion, crystalline isomalt was transformed into an amorphous form as shown by X-ray diffraction and differential scanning calorimetry (DSC). The tabletting properties of amorphous isomalt were dramatically improved. Mixtures formulated with paracetamol (50%) and extruded isomalt yielded hard tablets. However, extruded isomalt powder showed agglomeration problems due to recrystallization of the amorphous phase into a stable crystalline form in the presence of atmospheric moisture. The evolution of the moisture content correlated well with the compressibility data. The tablets made of extruded isomalt powder had a lower friability in comparison to the tablets formulated with non-extruded isomalt powder. Their disintegration was fast and a rapid dissolution rate was recorded. Extruded isomalt displayed excellent tabletting properties; however, further experiments should be conducted to delay or even prevent recrystallization of amorphous isomalt.

  17. Wool insulation

    Energy Technology Data Exchange (ETDEWEB)

    O`Shea, Angus

    1995-05-01

    Wool insulation usually comes in two forms, as loose fill or batts. The reliability of loose fill as an insulator, the thickness of batts and the wool`s vulnerability to insect and moth attack are considered to be problems. The purpose of this research was to create a commercial wool insulation product to overcome these limitations, at the same time withstanding the Australian and international standards for fire resistance. The project also considered the market potential of such a product with a view to commercialization. The loft or thickness problem was resolved by covering the wool with an oven baked adhesive. A fire retardant and anti-insect treatment was incorporated into the spray process to produce a viable product.

  18. Radiation Insulation

    Science.gov (United States)

    1995-01-01

    The Apollo and subsequent spacecraft have had highly effective radiation barriers; made of aluminized polymer film, they bar or let in heat to maintain consistent temperatures inside. Tech 2000, formerly Quantum International Corporation used the NASA technology in its insulating materials, Super "Q" Radiant Barrier, for home, industry and mobile applications. The insulation combines industrial aluminum foil overlaid around a core of another material, usually propylene or mylar. The outer layer reflects up to 97 percent of heat; the central layer creates a thermal break in the structure and thus allows low radiant energy emission. The Quantum Cool Wall, used in cars and trucks, takes up little space while providing superior insulation, thus reducing spoilage and costs. The panels can also dampen sound and engine, exhaust and solar heat.

  19. THE TECHNOLOGICAL AND EXPLOITATIVE FACTORS OF LOCAL INCREASE OF ELECTRIC FIELD STRENGTH IN THE POWER CABLE OF COAXIAL DESIGN

    Directory of Open Access Journals (Sweden)

    G. V. Bezprozvannych

    2016-12-01

    Full Text Available Introduction. Reliability of high voltage power cables in the process of long-term operation is largely due to the intensity of polymeric insulation aging. It is now established that the aging of polyethylene, which is the main material for the insulation of high voltage power cables, under the action of the electric field is determined primarily by the presence of structural heterogeneity arising both during cable production and during use. The cable is always there deviations from the ideal structure, which manifest in a deviation of diameters of conductors from nominal values; in the arrangement of the conductor and the insulation is not strictly coaxially and eccentrically; in elliptic (oval core and insulation; change in relative dielectric constant and thickness of insulation on cable length force the formation of low molecular weight products (including water in the flow at the manufacturing stage crosslinked polyethylene insulation and moisture during operation. Such defects are structural, technological and operational irregularities, which lead to a local change in the electric field. Purpose. Analysis of the influence of the eccentricity, elliptic and spherical inclusions in the electric field distribution in the power cable of a coaxial design with cross-linked polyethylene insulation, based on numerical simulation. Methodology. The bases of the numerical method of calculation of the electrical field strength are Fredholm integral equations of the first and second kind (method of secondary sources for an axially symmetric field. Analysis of the influence of irregularities, including water treeing, the shape of the sounding signal is made using the method of discrete resistive circuit inductance and capacitance of substitution with the initial conditions. Solving systems of linear algebraic equations nodal analysis performed by the sweep method. Results. The presence of the eccentricity and ellipticity in the construction of cable has

  20. A whole life assessment of extruded double base propellants

    OpenAIRE

    Tucker, J.

    2013-01-01

    The manufacturing process for solventless extruded double base propellants involves a number of rolling and reworking stages. Throughout these processes a decrease in weight average molecular weight was observed, this was attributed to denitration. Differential scanning calorimetery data indicated that the reworking stages of extruded double base propellant manufacture were crucial to the homogenisation of the propellant mixture. To determine the homogeneity of the final extruded product, a s...

  1. Progress of 275 kV-3 kA YBCO HTS cable

    Science.gov (United States)

    Yagi, M.; Mukoyama, S.; Amemiya, N.; Ishiyama, A.; Wang, X.; Aoki, Y.; Saito, T.; Ohkuma, T.; Maruyama, O.

    2011-11-01

    A 275 kV-3 kA high temperature superconducting (HTS) cable has been developed in the Materials & Power Applications of Coated Conductors (M-PACC) project. AC loss reduction of a two-layer HTS conductor was undertaken by removing the edges of YBCO tapes with low critical current density. The HTS conductor using these tapes was fabricated, and low loss of 0.235 W/m at 3 kA rms was achieved. The 275 kV-3 kA cable was designed, and the 2 m model cables were fabricated. This cable had 325 mm 2 copper stranded former inside the HTS conductor and a 310 mm 2 copper shield layer on the HTS shield layer for over-current protection. These cables withstood an over-current of 63.0 kA for 0.6 s, which is the worst situation for 275 kV systems. The partial discharge (PD) and V- t characteristics of a liquid nitrogen (LN 2)/polypropylene (PP) laminated paper composite insulation system have been integrated into the design of the insulation for the 275 kV cable. The results revealed that the PD inception stress (PDIE) did not depend on the insulation thickness, and that lifetime indices of V- t characteristics at PD inception were as high as about 80-100.

  2. High Temperature Superconducting Underground Cable

    Energy Technology Data Exchange (ETDEWEB)

    Farrell, Roger, A.

    2010-02-28

    The purpose of this Project was to design, build, install and demonstrate the technical feasibility of an underground high temperature superconducting (HTS) power cable installed between two utility substations. In the first phase two HTS cables, 320 m and 30 m in length, were constructed using 1st generation BSCCO wire. The two 34.5 kV, 800 Arms, 48 MVA sections were connected together using a superconducting joint in an underground vault. In the second phase the 30 m BSCCO cable was replaced by one constructed with 2nd generation YBCO wire. 2nd generation wire is needed for commercialization because of inherent cost and performance benefits. Primary objectives of the Project were to build and operate an HTS cable system which demonstrates significant progress towards commercial progress and addresses real world utility concerns such as installation, maintenance, reliability and compatibility with the existing grid. Four key technical areas addressed were the HTS cable and terminations (where the cable connects to the grid), cryogenic refrigeration system, underground cable-to-cable joint (needed for replacement of cable sections) and cost-effective 2nd generation HTS wire. This was the world’s first installation and operation of an HTS cable underground, between two utility substations as well as the first to demonstrate a cable-to-cable joint, remote monitoring system and 2nd generation HTS.

  3. Investigation of mechanism of breakdown in XLPE cables. Final report

    Energy Technology Data Exchange (ETDEWEB)

    McKean, A.L.

    1976-07-01

    The basic hypothesis that microporosity plays a significant role in the mechanism of breakdown of XLPE cable is explored. The potential improvement achieved by impregnating the microporous regions of the cable core with a neutral liquid is evaluated, with relation to ac voltage life and impulse strength. The effect at higher frequency is also demonstrated. A similar test program is pursued on model cables, designed to explore the effects of gas pressure and gas type on breakdown and life, since it is reasonable to expect that only the microporous regions of the insulation should be sensitive to the gas-pressure environment. Comparison of gas-pressurized model breakdown stress (and related microvoid size) with basic Paschen curves demonstrates reasonably good agreement, indicating that partial discharge is the basic mechanism of fatigue and breakdown. The form of the voltage life curve above and below the discharge inception level is proposed, and evidence is presented indicating breakdown originates in the bulk insulation as well as at the shield interface. It is also shown that model cable discharge energies are below 0.1 pC, even at very high stress, and cannot be measured with modern detectors. Results with liquid or gas impregnation suggest a possible approach to dielectric improvement.

  4. Topological insulators

    CERN Document Server

    Franz, Marcel

    2013-01-01

    Topological Insulators, volume six in the Contemporary Concepts of Condensed Matter Series, describes the recent revolution in condensed matter physics that occurred in our understanding of crystalline solids. The book chronicles the work done worldwide that led to these discoveries and provides the reader with a comprehensive overview of the field. Starting in 2004, theorists began to explore the effect of topology on the physics of band insulators, a field previously considered well understood. However, the inclusion of topology brings key new elements into this old field. Whereas it was

  5. 30 CFR 75.607 - Breaking trailing cable and power cable connections.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Breaking trailing cable and power cable... LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Trailing Cables § 75.607 Breaking trailing cable and power cable connections. Trailing cable and power cable connections...

  6. Study of Transient Heat Transport Mechanisms in Superfluid Helium Cooled Rutherford-Cables

    CERN Document Server

    AUTHOR|(CDS)2100615

    The Large Hadron Collider leverages superconducting magnets to focus the particle beam or keep it in its circular track. These superconducting magnets are composed of NbTi-cables with a special insulation that allows superfluid helium to enter and cool the superconducting cable. Loss mechanisms, e.g. continuous random loss of particles escaping the collimation system heating up the magnets. Hence, a local temperature increase can occur and lead to a quench of the magnets when the superconductor warms up above the critical temperature. A detailed knowledge about the temperature increases in the superconducting cable (Rutherford type) ensures a secure operation of the LHC. A sample of the Rutherford cable has been instrumented with temperature sensors. Experiments with this sample have been performed within this study to investigate the cooling performance of the helium in the cable due to heat deposition. The experiment uses a superconducting coil, placed in a cryostat, to couple with the magnetic field loss m...

  7. New Structure of Optical Fiber Protection Cable Using Helical Composite Spring

    Science.gov (United States)

    Chung, Seunghwan; Yoon, Youngki; Lee, Woo‑Il; Lee, Byoungho

    2006-07-01

    A new type of cable is introduced for protecting optical fiber from mechanical bending or abrupt temperature changes. It shows superior ability to protect fiber from severe bending and lowers the thermal sensitivity compared with conventional optical fiber cable. It can be used as a protection sleeve or cable in special regions. The proposed device consists of a helical composite spring, a thermal insulator (i.e., polyurethane foam) and a heat-shrinkable tube which coats the outside of the spring. These components can be acquired for a moderate price and manufactured by simple processes.

  8. A study on the condition monitoring for safety-related electric cables

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Chul Hwan; Ahn, S. P.; Yeo, S. M.; Kang, Y. S.; Ahn, S. M.; Kim, I. S.; Kim, D. S.; Kang, J. S. [Sungkyunkwan Univ., Suwon (Korea, Republic of)

    2002-03-15

    In this report, we have studied compositions and characteristics of various types of insulation material for cables in Nuclear Power Plant. We arrange relationship with condition monitoring methods. Also, we propose new condition monitoring method using third harmonic frequency. We test the proposed method with CV cables. We also describe about feature of condition monitoring such as application, theory, characteristic, thereby other engineer can confirm to advantage and disadvantage for each method, and possibly choice adequate condition monitoring method for various types of cables.

  9. Literature review of environmental qualification of safety-related electric cables: Summary of past work. Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    Subudhi, M. [Brookhaven National Lab., Upton, NY (United States)

    1996-04-01

    This report summarizes the findings from a review of published documents dealing with research on the environmental qualification of safety-related electric cables used in nuclear power plants. Simulations of accelerated aging and accident conditions are important considerations in qualifying the cables. Significant research in these two areas has been performed in the US and abroad. The results from studies in France, Germany, and Japan are described in this report. In recent years, the development of methods to monitor the condition of cables has received special attention. Tests involving chemical and physical examination of cable`s insulation and jacket materials, and electrical measurements of the insulation properties of cables are discussed. Although there have been significant advances in many areas, there is no single method which can provide the necessary information about the condition of a cable currently in service. However, it is possible that further research may identify a combination of several methods that can adequately characterize the cable`s condition.

  10. [Insect pests dissemination by extruded starch packages].

    Science.gov (United States)

    Fraga, Felipe B; Alencar, Isabel D C C; Tavares, Marcelo T

    2009-01-01

    We observed the viability of extruded starch products used as impact protector for fragile packing as a food source of the following stored grains pests: Cryptolestes ferrugineus (Stephens), Lasioderma serricorne (Fabr.), Oryzaephilus surinamensis (L.), Sitophilus oryzae (L.), Tribolium castaneum (Herbst) (Coleoptera) and Plodia interpunctella (Hübner) (Lepidoptera). Cryptolestes ferrugineus, L. serricorne and T. castaneum were found in these products, which are used by them as shelter and food. Under experimentation, we observed the development of O. surinamensis, S. oryzae and P. interpunctella feeding on this food source. Thus, it is recorded the viability of such material to be a potential dispersal vehicle to spread insect pests.

  11. Pediatrics and Cable Television.

    Science.gov (United States)

    Wallerstein, Edward; And Others

    The Department of Community Medicine of the Mount Sinai School of Medicine (New York City), in cooperation with the TelePrompTer Corporation and with funding from the Health Services and Mental Health Administration of the Department of Health, Education, and Welfare, has developed a bidirectional television system using coaxial cable which links…

  12. Cable Aerodynamic Control

    DEFF Research Database (Denmark)

    Kleissl, Kenneth

    to a categorization of the different control technics together with an identification of two key mechanisms for reduction of the design drag force. During this project extensive experimental work examining the aerodynamics of the currently used cable surface modifications together with new innovative proposals have...

  13. Lightweight Electric Power Cable.

    Science.gov (United States)

    1982-09-01

    8I~ .4 111 162 MICROCi Pi RL’ LUHION TESI CHARI "LIGHTWEIGHT ELECTRIC POWER CABLE" FINAL TECHNICAL REPORT SEPTEMBER 30, 1981 to SEPTEMBER 30, 1982... Vulcanized by heat to crosslink. TPE (Thermoplastic Elastomer) - Polymers having elastomeric proper- ties. Used as thermoplastics - melt formed by

  14. Handbook for photovoltaic cabling

    Energy Technology Data Exchange (ETDEWEB)

    Klein, D. N.

    1980-08-01

    This volume, originally written as part of the Interim Performance Criteria Document Development Implementation Plan and Procedures for Photovoltaic Energy Systems, is an analysis of the several factors to be considered in selecting cabling for photovoltaic purposes. These factors, correspoonding to chapter titles, are electrical, structural, safety, durability/reliability, and installation. A glossary of terms used within the volume is included for reference.

  15. Radiation Testing of a Low Voltage Silicone Nuclear Power Plant Cable.

    Energy Technology Data Exchange (ETDEWEB)

    Bernstein, Robert

    2014-08-01

    This report summarizes the results generated in FY13 for cable insulation in support of DOE's Light Water Reactor Sustainability (LWRS) Program, in collaboration with the US- Argentine Binational Energy Working Group (BEWG). A silicone (SiR) cable, which was stored in benign conditions for %7E30 years, was obtained from Comision Nacional de Energia Atomica (CNEA) in Argentina. Physical property testing was performed on the as-received cable. This cable was artificially aged to assess behavior with additional analysis. SNL observed appreciable tensile elongation values for all cable insulations received, indicative of good mechanical performance. Of particular note, the work presented here provides correlations between measured tensile elongation and other physical properties that may be potentially leveraged as a form of condition monitoring (CM) for actual service cables. It is recognized at this point that the polymer aging community is still lacking the number and types of field returned materials that are desired, but SNL -- along with the help of others -- is continuing to work towards that goal. This work is an initial study that should be complimented with location- mapping of environmental conditions of CNEA plant conditions (dose and temperature) as well as retrieval, analysis, and comparison with in-service cables.

  16. Radiation Testing of a Low Voltage Silicone Nuclear Power Plant Cable.

    Energy Technology Data Exchange (ETDEWEB)

    White II, Gregory Von; Schroeder, John Lee.; Sawyer, Patricia Sue.; Wichhart, Derek; Mata, Guillermo Adrian; Zorrilla, Jorge; Bernstein, Robert

    2014-09-01

    This report summarizes the results generated in FY13 for cable insulation in support of the Department of Energy's Light Water Reactor Sustainability (LWRS) Program, in collaboration with the US-Argentine Binational Energy Working Group (BEWG). A silicone (SiR) cable, which was stored in benign conditions for %7E30 years, was obtained from Comision Nacional de Energia Atomica (CNEA) in Argentina with the approval of NA-SA (Nucleoelectrica Argentina Sociedad Anonima). Physical property testing was performed on the as-received cable. This cable was artificially aged to assess behavior with additional analysis. SNL observed appreciable tensile elongation values for all cable insulations received, indicative of good mechanical performance. Of particular note, the work presented here provides correlations between measured tensile elongation and other physical properties that may be potentially leveraged as a form of condition monitoring (CM) for actual service cables. It is recognized at this point that the polymer aging community is still lacking the number and types of field returned materials that are desired, but Sandia National Laboratories (SNL) -- along with the help of others -- is continuing to work towards that goal. This work is an initial study that should be complimented with location-mapping of environmental conditions of Argentinean plant conditions (dose and temperature) as well as retrieval, analysis, and comparison with in- service cables.

  17. Electric and Thermal Properties of Wet Cable 10kV and 15kV

    Directory of Open Access Journals (Sweden)

    K. Rajagopala

    2012-11-01

    Full Text Available The increased temperature of the cable insulation with rising load currents, are known to accelerate the formation of water and electric trees in cables which ultimately lead to cables failure. There are several factors which will determine the thermal and electrical behaviour of a given wet cable installation. These include the assumed ampacity, the cable construction and circumstances of installation, the thermal properties of the surrounding soil and the electrical properties. The work presented in this paper involves the use of COMSOL multiphysics finite element software to develop an integrated electrical, thermal model with 5micro meter and 2.5 micro meter water bubble radius. The presence of water tree results in the reduction of their dielectric strength. Here the finite element simulation technique is used to evaluate the electric field, potential and temperature distribution inside the 10 kV and 15 kV power cables. A model that illustrates the water-dielectric interface within the cable insulation system is proposed.

  18. Translucent Insulation

    DEFF Research Database (Denmark)

    Rahbek, Jens Eg

    1998-01-01

    Two new types of translucent materials are presented. One is translucent fiber insulation and the other type is a new type of hony-comb made of Celulose-acetat. Data for the materials and calculations of energy savings when using the materials in building envelopes are presented....

  19. LONG TERM OPERATION ISSUES FOR ELECTRICAL CABLE SYSTEMS IN NUCLEAR POWER PLANTS

    Energy Technology Data Exchange (ETDEWEB)

    Fifield, Dr Leonard S [Pacific Northwest National Laboratory (PNNL); Duckworth, Robert C [ORNL; Glass III, Dr. Samuel W. [Pacific Northwest National Laboratory (PNNL)

    2016-01-01

    Nuclear power plants contain hundreds of kilometers of electrical cables including cables used for power, for instrumentation, and for control. It is essential that safety-related cable systems continue to perform following a design-basis event. Wholesale replacement of electrical cables in existing plants facing licensing period renewal is both impractical and cost-prohibitive. It is therefore important to understand the long term aging of cable materials to have confidence that aged cables will perform when needed. It is equally important in support of cable aging management to develop methods to evaluate the health of installed cables and inform selective cable replacement decisions. The most common insulation materials for electrical cables in nuclear power plants are cross-linked polyethylene and ethylene-propylene rubber. The mechanical properties of these materials degrade over time in the presence of environmental stresses including heat, gamma irradiation, and moisture. Mechanical degradation of cable insulation beyond a certain threshold is unacceptable because it can lead to insulation cracking, exposure of energized conductors, arcing and burning or loss of the ability of the cable system to function during a design-basis accident. While thermal-, radiation-, and moisture-related degradation of polymer insulation materials has been extensively studied over the last few decades, questions remain regarding the long-term performance of cable materials in nuclear plant-specific environments. Identified knowledge gaps include an understanding of the temperature-dependence of activation energies for thermal damage and an understanding of the synergistic effects of radiation and thermal stress on polymer degradation. Many of the outstanding questions in the aging behavior of cable materials relate to the necessity of predicting long-term field degradation using accelerated aging results from the laboratory. Materials degrade faster under more extreme

  20. Flat conductor cable commercialization project

    Science.gov (United States)

    Hogarth, P.; Wadsworth, E.

    1977-01-01

    An undercarpet flat conductor cable and a baseboard flat conductor cable system were studied for commercialization. The undercarpet system is designed for use in office and commercial buildings. It employs a flat power cable, protected by a grounded metal shield, that terminates in receptacles mounted on the floor. It is designed to interface with a flat conductor cable telephone system. The baseboard system consists of a flat power cable mounted in a plastic raceway; both the raceway and the receptacles are mounted on the surface of the baseboard. It is designed primarily for use in residential buildings, particularly for renovation and concrete and masonry construction.

  1. Tapping the television cable.

    Science.gov (United States)

    Clarke, M; Findlay, A; Canac, J F; Vergez, A

    1996-01-01

    Immediate access to patient data is essential to support good clinical decision making and support. However, away from the surgery, the doctor is currently unable to have any access to the clinical database. Solutions exist to support remote access, such as modems or radio data networks, but these are slow, with typical speeds in the 2-10 kbaud region. We propose a novel solution, to use the TV cable already installed in many homes. Using this technology, a suitably equipped computer (RF modern) is capable of connecting at speeds in excess of 500 kbaud and will run applications in exactly the same way as if connected to a surgery network: the cable TV becomes a LAN, but on a metropolitan scale. Brunel University, in collaboration with the Cable Corporation, has been piloting such a network. Issues include not only levels of service, but also security on the network and access, since the data are being effectively received in every home. However, close scrutiny of channel use can create closed networks reserved for specific users. The technology involves use of an RF modem to transmit data on a reverse channel (based at 16 MHz) on each subnet to a router at the head end of the cable network. This frequency translates the packet and retransmits it to all the subnets on a forward channel (based at 178 MHz). Each channel occupies the bandwidth normally allocated to one TV channel. Access is based on a modified CSMA/CD protocol, so treating the cable network as single multiple access network. The modem comes as a standard card installed in a PC and appears much as an ethernet card, but at reduced speed. With an NDIS driver it is quite able to support almost any network software, and has successfully demonstrated Novell and TCP/IP. We describe the HomeWorker network and the results from a pilot study being undertaken to determine the performance of the system and its impact on working practice.

  2. The counter-rotating twin screw extruder as a polymerization reactor

    NARCIS (Netherlands)

    Ganzeveld, Klaassien Jakoba

    1992-01-01

    The goal of the research was to examine the possibilities of this type of extruder as a polymerization reactor, and to develop models of the extruder reactor which accurately describe the reaction progress in the extruder. See summary

  3. Progress in the development of gas-impregnated lapped plastic film insulation

    Energy Technology Data Exchange (ETDEWEB)

    Forsyth, E B; McNerney, A J; Muller, A C; Rigby, S J

    1977-01-01

    A flexible superconducting power transmission cable is under development. The electrical insulation consists of lapped polymeric film tapes impregnated with supercritical helium. Ways of satisfying the many constraints on the material were described. Although the cable is intended for low-temperature operation good electrical and mechanical characteristics are needed at room-temperature. Results are given for both small-sample tests and a model cable fabricated commercially. The results are compared with those obtained by other workers and the design of the next test cable is given.

  4. Tests of Insulation Systems for Nb3SN Wind and React Coils

    Science.gov (United States)

    Bossert, R.; Ambrosio, G.; Andreev, N.; Whitson, G.; Zlobin, A.

    2008-03-01

    Tests were performed to assess the viability of several cable insulation systems for use in Nb3Sn accelerator magnets. Insulated stacks of cables were subjected to reaction cycles commonly used for Nb3Sn coils. After reaction and epoxy impregnation, current leakage between turns was measured at pressures up to 180 MPa and turn-to-turn potentials up to 500 V. Systems consisting of S-2 glass, ceramic fiber, and E-glass were tested. Several methods of applying the insulation were incorporated, including sleeves and various spiral wrapped configurations. Methods of sample preparation and testing are described and results are reported.

  5. The Applications of Current Comparators in the Measurements on High Voltage Insulation

    Directory of Open Access Journals (Sweden)

    Fei Yi-jun

    2016-01-01

    Full Text Available This paper describes the basic structure of the current comparator used for high voltage insulation measurements. Further applications for the current comparator in high voltage insulation are investigated and developed. A measuring system for the measurement of harmonics in the loss current of water tree aged insulation is described, as well as the principles to measure partial discharges with the current comparator bridge. A new system for the measurement of the DC component in the leakage current of insulation is de1veloped and presented. The results of experiments on XLPE cable insulation are also given.

  6. Method to improve superconductor cable

    Science.gov (United States)

    Borden, A.R.

    1984-03-08

    A method is disclosed of making a stranded superconductor cable having improved flexing and bending characteristics. In such method, a plurality of superconductor strands are helically wound around a cylindrical portion of a mandrel which tapers along a transitional portion to a flat end portion. The helically wound strands form a multistrand hollow cable which is partially flattened by pressure rollers as the cable travels along the transitional portion. The partially flattened cable is impacted with repeated hammer blows as the hollow cable travels along the flat end portion. The hammer blows flatten both the internal and the external surfaces of the strands. The cable is fully flattened and compacted by two sets of pressure rollers which engage the flat sides and the edges of the cable after it has traveled away from the flat end portion of the mandrel. The flattened internal surfaces slide easily over one another when the cable is flexed or bent so that there is very little possibility that the cable will be damaged by the necessary flexing and bending required to wind the cable into magnet coils.

  7. EIGENFREQUENCY ANALYSIS OF CABLE STRUCTURES WITH INCLINED CABLES

    Institute of Scientific and Technical Information of China (English)

    William Paulsen; Greg Slayton

    2006-01-01

    The approximate eigenfrequencies for the in-plane vibrations of a cable structure consisting of inclined cables, together with point masses at various points were computed. It was discovered that the classical transfer matrix method was inadequate for this task, and hence the larger exterior matrices were used to determine the eigenfrequency equation. Then predictions of the dynamics of the general cable structure based on the asymptotic estimates of the exterior matrices were made.

  8. 14 CFR 23.689 - Cable systems.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Cable systems. 23.689 Section 23.689... Systems § 23.689 Cable systems. (a) Each cable, cable fitting, turnbuckle, splice, and pulley used must meet approved specifications. In addition— (1) No cable smaller than 1/8 inch diameter may be used...

  9. Cabling design of booster and storage ring construction progress of TPS

    Science.gov (United States)

    Wong, Y.-S.; Liu, K.-B.; Liu, C.-Y.; Wang, b.-S.

    2017-06-01

    The 2012 Taiwan Photon Source (TPS) cable construction project started after 10 months to complete the cable laying and installation of power supply. The circumference of the booster ring (BR) is 496.8 m, whereas that of the storage ring (SR) is 518.4 m. Beam current is set to 500 mA at 3.3 GeV. The paper on grounding systems discusses the design of the ground wire (bending dipole; the cable size of its stranded wire measures 250 mm2, with a total length of 5000 m. Booster ring and storage ring quadrupoles have 150 magnets; the cable size of their stranded wire is 250 mm2, with a total length of 17000 m. Storage ring dipole consists of 48 magnets; the cable size of its stranded wire is 325 mm2, with a total length of 6000 m. This study discusses the power supply cabling design of the storage ring and booster ring construction progress of TPS. The sections of this paper are divided into discussions of the construction of the control and instrument area, cabling layout of booster ring and storage ring, as well as the installation and commission machine. This study also discusses the use of a high-impedance meter to determine the effect of cabling insulation and TPS power supply machine on energy transfer to ensure the use of safe and correct magnet.

  10. Approach for Wide Use of Diagnostic Method for XLPE Cables Using Harmonics in AC Loss Current

    Science.gov (United States)

    Tsujimoto, Tomiyuki; Nakade, Masahiko; Yagi, Yukihiro; Ishii, Noboru

    Water tree is one of the degradation aspects of XLPE cables used for under-ground distribution or transmission lines. We have developed the loss current method using 3rd harmonic in AC loss current for cable diagnosis. Harmonic components in loss current arise as a result of the non-linear voltage-current characteristics of water trees. We confirmed that the 3rd harmonic in AC loss current had good correlation with water tree growth and break down strength. After that, we have applied this method to the actual 66kV XLPE cable lines. Up to now, the number of the application results is more than 130 lines. In case of cable lines terminated at gas-insulated switchgear (GIS), we have to remove the lightning arrestor (LA) and the potential transformer (PT) out of the test circuit. The reason is that we are afraid that each of LA and PT disturbs the degradation signal from cable lines. It takes extra time (1 or 2 days) and costs more to remove LA and PT in GIS out of a circuit. In order to achieve easy and reasonable diagnosis, we have developed a new method for cable lines terminated at GIS, by utilizing a technique, which enables to reduce signal of LA and PT from disturbed signal of cable lines. We confirmed the effect of the new method by experiments with actual cables.

  11. Quality Control of Extruded HVDC Cables: Detection of Critical Flaws Using Low Frequency Voltage Endurance Testing%Quality Control of Extruded HVDC Cables: Detection of Critical Flaws Using Low Frequency Voltage Endurance Testing

    Institute of Scientific and Technical Information of China (English)

    Erling Ildstad; Frank Mauseth; Mildrid Selsjord; Roll Hegerberg

    2011-01-01

    The main purpose of the work presented here is to evaluate different methods for quality control of polymer- ic insulated HVDC cables. The insight gained can be used to evaluate proposed test methods for quality assurance of long lengths of polymer insulated power cables. Laboratory experiments were performed using both Rogowski shaped test objects and model cables, insulated with XLPE containing imbedded spherically shaped particles. Tests were per- formed by stressing the test object with AC (50 Hz), VLF (0.1 Hz) and DC voltages and measuring time to break- down at the different voltages. The slope of the voltage-time curve for 0. land 50 Hz were found to be parallel show- ing higher breakdown strength for 0.1 Hz than 50 Hz. The number of periods to breakdown is somewhat higher for 0.1 Hz than for 50 Hz. The breakdown strength for DC was~ much higher than for both AC 50 Hz and 0.1 Hz. The results indicate that the VLF test voltage needs to be 2 to 3 times higher than at 50 Hz power frequency in order to eliminate the same defects within a comparable time.

  12. Ultrasonic Welding of Wires and Cables

    Science.gov (United States)

    Heinz, Stefan; Wagner, Guntram; Eifler, Dietmar

    2012-03-01

    In the automobile industry, ultrasonic metal welding is an established method. At the Institute of Materials Science and Engineering (WKK) at the University of Kaiserslautern, Germany, systematic investigations of the weldability of Al-wires and flat flexible copper cables were carried out. In the case of Al-wires, joints with cross-sectional area of up to 80 mm2 and tensile shear load of about 3500 N were finally realized. Furthermore, methods to reduce unintentional adherence between the sonotrode coupling face and the Al-wires were developed. To realize FFC joints, ultrasonic spot welding systems and ultrasonic torsion welding systems were used. A central purpose of these investigations is the development of a system to enable welding through the insulation of the FFC without weakening the base material.

  13. Brillouin distributed temperature sensing system for monitoring of submarine export cables of off-shore wind farms

    Science.gov (United States)

    Marx, Benjamin; Rath, Alexander; Kolm, Frederick; Schröder, Andreas; Buntebarth, Christian; Dreß, Albrecht; Hill, Wieland

    2016-05-01

    For high-voltage cables, the maximum temperature of the insulation must never be exceeded at any location and at any load condition. The local temperatures depend not only on the cable design and load history, but also on the local thermal environment of the cable. Therefore, distributed temperature monitoring of high-voltage cables is essential to ensure the integrity of the cable at high load. Especially, the load of the export cables of wind farms varies strongly in dependence on weather conditions. In this field study, we demonstrate the measurement performance of a new, robust Brillouin distributed temperature sensing system (Brillouin-DTS). The system is based on spontaneous Brillouin scattering and does not require a fibre loop. This is essential for long submarine high-voltage cables, where normally no loop can be formed in the seabed. It is completely passively cooled and does not contain any moving or wearing parts. The instrument is dedicated for use in industrial and other rough environments. With a measuring time below 10 min, the temperature resolution is better than 1 °C for distances up to 50 km. In the field study, the submarine export cable of an off-shore wind farm has been monitored. The temperature profile of the export cable shows several hot spots, mostly located at cable joints, and also several cold spots.

  14. Cable networks, services, and management

    CERN Document Server

    2015-01-01

    Cable Networks, Services, and Management is the first book to cover cable networks, services, and their management, in-depth, for network operators, engineers, researchers, and students. Thirteen experts in various fields have contributed their knowledge of network architectures and services, Operations, Administration, Maintenance, Provisioning, Troubleshooting (OAMPT) for residential and business services, cloud, Software Defined Networks (SDN), as well as virtualization concepts and their applications as part of the future directions of cable networks. The book begins by introducing architecture and services for Data Over Cable Service Interface Specification (DOCSIS) 3.0/ 3.1, Converged Cable Access Platform (CCAP), Content Distribution Networks (CDN, IP TV, and Packet Cable and Wi-Fi for Residential Services. Topics that are discussed in proceeding chapters include: operational systems and management architectures, service orders, provisioning, fault manageme t, performance management, billing systems a...

  15. Technology for long cable erection of a thousand-meter scale cable-stayed bridge

    Institute of Scientific and Technical Information of China (English)

    Rao Huarong; Deng Huibin

    2009-01-01

    In the background of the construction of Sutong Yangtze River Bridge (short as Sutong Bridge), the cable construction method and techniques of a thousand-meter scale cable-stayed bridge are introduced. Some key construction techniques, such as outspreading cable on deck, installing cable at pylon, pulling and fixing cable at the attachment with decks and cable PE sheath protection are discussed.

  16. Ionizing radiation effects on ISS ePTFE jacketed cable assembly

    Science.gov (United States)

    Koontz, S. L.; Golden, J. L.; Lorenz, M. J.; Pedley, M. D.

    2003-09-01

    Polytetrafluoroethylene (PTFE), which is susceptible to embrittlement by ionizing radiation, is used as a primary material in the Mobile Transporter's (MT) Trailing Umbilical System (TUS) cable on the International Space Station (ISS). The TUS cable provides power and data service between the ISS truss and the MT. The TUS cable is normally stowed in an uptake reel and is fed out to follow the MT as it moves along rails on the ISS truss structure. For reliable electrical and mechanical performance, TUS cable polymeric materials must be capable of >3.5% elongation without cracking or breaking. The MT TUS cable operating temperature on ISS is expected to range between -100°C and +130°C. The on-orbit functional life requirement for the MT TUS cable is 10 years. Analysis and testing were performed to verify that the MT TUS cable would be able to meet full-life mechanical and electrical performance requirements, despite progressive embrittlement by the natural ionizing radiation environment. Energetic radiation belt electrons (trapped electrons) are the principal contributor to TUS cable radiation dose. TUS cable specimens were irradiated, in vacuum, with both energetic electrons and gamma rays. Electron beam energy was chosen to minimize charging effects on the non-conductive ePTFE (expanded PTFE) targets. Tensile testing was then performed, over the expected range of operating temperatures, as a function of radiation dose. When compared to the expected in-flight radiation dose/depth profile, atomic oxygen (AO) erosion of the radiation damaged TUS cable jacket surfaces is more rapid than the development of radiation induced embrittlement of the same surfaces. Additionally, the layered construction of the jacket prevents crack growth propagation, leaving the inner layer material compliant with the design elongation requirements. As a result, the TUS cable insulation design was verified to meet performance life requirements.

  17. Dynamic testing of cable structures

    Directory of Open Access Journals (Sweden)

    Caetano Elsa

    2015-01-01

    Full Text Available The paper discusses the role of dynamic testing in the study of cable structures. In this context, the identification of cable force based on vibration measurements is discussed. Vibration and damping assessment are then introduced as the focus of dynamic monitoring systems, and particular aspects of the structural behaviour under environmental loads are analysed. Diverse application results are presented to support the discussion centred on cable-stayed bridges, roof structures, a guyed mast and a transmission line.

  18. Cable Bacteria in Freshwater Sediments

    OpenAIRE

    Risgaard-Petersen, Nils; Kristiansen, Michael; Frederiksen, Rasmus B.; Dittmer, Anders Lindequist; Bjerg, Jesper Tataru; Trojan, Daniela; Schreiber, Lars; Damgaard, Lars Riis; Schramm, Andreas; Nielsen, Lars Peter

    2015-01-01

    In marine sediments cathodic oxygen reduction at the sediment surface can be coupled to anodic sulfide oxidation in deeper anoxic layers through electrical currents mediated by filamentous, multicellular bacteria of the Desulfobulbaceae family, the so-called cable bacteria. Until now, cable bacteria have only been reported from marine environments. In this study, we demonstrate that cable bacteria also occur in freshwater sediments. In a first step, homogenized sediment collected from the fre...

  19. Electromagnetic transients in power cables

    CERN Document Server

    da Silva, Filipe Faria

    2013-01-01

    From the more basic concepts to the most advanced ones where long and laborious simulation models are required, Electromagnetic Transients in Power Cables provides a thorough insight into the study of electromagnetic transients and underground power cables. Explanations and demonstrations of different electromagnetic transient phenomena are provided, from simple lumped-parameter circuits to complex cable-based high voltage networks, as well as instructions on how to model the cables.Supported throughout by illustrations, circuit diagrams and simulation results, each chapter contains exercises,

  20. STATIC ANALYSIS OF CABLE STRUCTURE

    Institute of Scientific and Technical Information of China (English)

    HUANG Yan; LAN Wei-ren

    2006-01-01

    Based on the nonlinear geometric relation between strain and displacement for flexible cable, the equilibrium equation under self-weight and influence of temperature was established and an analytical solution of displacement and tension distribution defined in Eulerian coordinate system was accurately obtained. The nonlinear algebraic equations caused by cable structure were solved directly using the modified Powell hybrid algorithm with high precision routine DNEQNE of Fortran. For example, a cable structure consisting of three cables jointly supported by a vertical spring and all the other ends fixed was calculated and compared with various methods by other scholars.

  1. Detail of photo 7903109 stack of superconducting cables in the modulus measuring device

    CERN Multimedia

    1979-01-01

    The picture shows an assembly of insulated superconducting cables of the type used in the Po dipole magnet inserted in the elastic modulus measuring device (photos 7903547X and 7903169) in order to measures its mechanical properties under azimuthal compression. See also 7903547X, 7903169, 8307552X.

  2. Thermal and Microstructural Property of Extruded Snack: An Overview

    Directory of Open Access Journals (Sweden)

    Mahuya Hom Choudhury,

    2014-02-01

    Full Text Available Rice and Chapra (Fenneropenaeus indicus mixture were extruded using a co rotating fully intermeshing twin-screw extruder to prepare carbohydrate protein based snack. The aim of the present work is to study the glass transition temperature and microstructural behaviour of carbohydrate-protein extrudate snack. Parkin Elmer Differential Scanning Calorimeter method was used for studying phase transition behaviour of complex carbohydrate-protein extrudate at a heating rate of 5ºC/min and in the temperature range - 80ºC to 180ºC. On the other hand, Scanning Electron Microscope (SEM was used to study the microstructural behavior of multicomponent extrudate at an accelerating voltage of 20 kV and at 1000 X magnification. State diagram indicated phase separation of carbohydrate-protein complex food system at macromolecular level. The glass transition temperature of protein dictated the texture of the mixed system. At room temperature, extrudate with 15% moisture is glassy while extrudates obtained <15% moisture shows rubbery texture and higher moisture profile shows burnt texture. Microstructural analysis performed by SEM shows typical network like structure at 150C and 15% moisture.

  3. Fire behavior of halogen-free flame retardant electrical cables with the cone calorimeter.

    Science.gov (United States)

    Meinier, Romain; Sonnier, Rodolphe; Zavaleta, Pascal; Suard, Sylvain; Ferry, Laurent

    2017-08-14

    Fires involving electrical cables are one of the main hazards in Nuclear Power Plants (NPPs). Cables are complex assemblies including several polymeric parts (insulation, bedding, sheath) constituting fuel sources. This study provides an in-depth characterization of the fire behavior of two halogen-free flame retardant cables used in NPPs using the cone calorimeter. The influence of two key parameters, namely the external heat flux and the spacing between cables, on the cable fire characteristics is especially investigated. The prominent role of the outer sheath material on the ignition and the burning at early times was highlighted. A parameter of utmost importance called transition heat flux, was identified and depends on the composition and the structure of the cable. Below this heat flux, the decomposition is limited and concerns only the sheath. Above it, fire hazard is greatly enhanced because most often non-flame retarded insulation part contributes to heat release. The influence of spacing appears complex, and depends on the considered fire property. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. High Frequency Tan Delta Measurement Method for 132kV Transmission Underground Cables

    Directory of Open Access Journals (Sweden)

    A.R. Avinash

    2015-07-01

    Full Text Available Tangent Delta is a measurement technique to investigate cables insulation strength. Current techniques utilize Very Low Frequency (VLF at 0.1 Hz and power frequency at 50 Hz. However, high voltages are required, thus requiring larger space and cost. Proposed method of tangent delta testing utilizes High frequency Low voltage diagnoses. The phase between the current and the voltage is utilized to determine the tangent delta (tan δ. The aim of this study is to develop a low voltage high frequency tangent delta measurement method and test if it can discriminate manufactured 132 kV good conditioned cable sample from defect induced cables with void, scotched and contamination in its insulation. Impurities are clearly discriminated using this method. Comparison of Tangent Delta of cables manufactured simultaneously in good condition and defect induced is performed using High Frequency Tangent Delta method and in 50 Hz conventional method to validate the effectiveness of the measurement technique. The High Frequency AC setup utilizes a small testing environment which can sample small lengths with minimum 1 m length of cable. The small lengths will result in the reduction of total capacitance of the cable but using High Frequency induces high electric stress on XLPE layer thus resulting in measureable dielectric current.

  5. Helium II heat transfer in LHC magnets : polyimide cable insulation

    NARCIS (Netherlands)

    Winkler, Tiemo

    2017-01-01

    Today’s large particle accelerators like the LHC at CERN are using superconducting materials as a construction material for magnets. These magnets need to be cooled constantly to temperatures below the critical surface of the superconducting material. In the LHC this is achieved by using liquid

  6. Discussion on the cable type selection and laying method%谈电缆选型及敷设方式

    Institute of Scientific and Technical Information of China (English)

    刘亚涛

    2016-01-01

    从导体材料、芯数、绝缘水平、绝缘材料、护层等方面,介绍了电缆的类型及选择原则,并阐述了电缆截面与电缆敷设方式的选择方法,有利于保证电缆运行的安全可靠性。%From the conductor material,core number,insulation level,insulation material,sheath and other aspects,this paper introduced the cable types selection and selection principles,and elaborated the selection method of cable section and cable laying methods,to ensure the safety and reliability of cable operation.

  7. DOE-sponsored aging management guideline for electrical cable and terminators

    Energy Technology Data Exchange (ETDEWEB)

    Gazdzinski, R.F. [Ogden Enviromental and Energy Services, Inc., Blue Bell, PA (United States)

    1996-03-01

    The DOE-sponsored Aging Management Guideline (AMG) for Electrical Cable and Terminations provides an analysis of the potential age-related degradation mechanisms and effects for low-voltage and medium-voltage extruded cables and associated terminations used in commercial nuclear power plants. The AMG examined historical industry failure data and correlated this with postulated aging mechanisms and effects. Existing and developmental testing and condition monitoring techniques were evaluated, as well as current industry practices, in order to assess whether all significant aging mechanisms/effects are being effectively managed. Results of the study indicate that some aging mechanisms and effects are not directly addressed by current industry maintenance and surveillance practices; however, empirical evidence indicates that low- and medium-voltage cable and terminations are in general very reliable. A limited number of nondestructive (or essentially nondestructive) techniques currently available are potentially useful for evaluating low-voltage cable condition; however, such techniques do not currently exist for monitoring medium-voltage cable. Troubleshooting or diagnostic techniques are available to identify certain types of degradation.

  8. Use of very low frequency technology for diagnostic in medium voltage electric cables; Utilizacao da tecnologia VLF para diagnostico de cabos eletricos de media tensao

    Energy Technology Data Exchange (ETDEWEB)

    Martinez, Flavio Costa; Pinho, Wilson Pereira de [Companhia Siderurgica Nacional (CSN), Volta Redonda, RJ (Brazil). Gerencia de Distribuicao de Energeticos

    2010-07-01

    The present technical contribution presents a new technology used in the Companhia Siderurgica Nacional (CSN) to diagnose operating conditions, useful life and faults in medium voltage electrical cables. The Very Low Frequency is a nondestructive electrical testing, conducted in medium voltage electrical cables, designed to measure the overall state of insulation of the cables, and the precise location of the fault before the failure. Through two types of tests, Delta Tangent and Partial Discharge, it is possible to make a complete diagnosis of insulation performance of the cable and also detect the fault. The implantation of this predictive technique, will monitor the useful life of medium voltage cables, avoiding potential failures in electrical circuits of Usina Presidente Vargas, allowing the intervention of maintenance before the failure, that result in interference in the production process. (author)

  9. Studying radiolytic ageing of nuclear power plant electric cables with FTIR spectroscopy.

    Science.gov (United States)

    Levet, A; Colombani, J; Duponchel, L

    2017-09-01

    Due to the willingness to extend the nuclear power plants length of life, it is of prime importance to understand long term ageing effect on all constitutive materials. For this purpose gamma-irradiation effects on insulation of instrumentation and control cables are studied. Mid-infrared spectroscopy and principal components analysis (PCA) were used to highlight molecular modifications induced by gamma-irradiation under oxidizing conditions. In order to be closer to real world conditions, a low dose rate of 11Gyh(-1) was used to irradiate insulations in full cable or alone with a dose up to 58 kGy. Spectral differences according to irradiation dose were extracted using PCA. It was then possible to observe different behaviors of the insulation constitutive compounds i.e. ethylene vinyl acetate (EVA), ethylene propylene diene monomer (EPDM) and aluminium trihydrate (ATH). Irradiation of insulations led to the oxidation of their constitutive polymers and a modification of filler-polymer ratio. Moreover all these modifications were observed for insulations alone or in full cable indicating that oxygen easily diffuses into the material. Spectral contributions were discussed considering different degradation mechanisms. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Effect of corrugated characteristics on the liquid nitrogen temperature field of HTS cable

    Science.gov (United States)

    Li, Z. M.; Li, Y. X.; Zhao, Y. Q.; Gao, C.; Qiu, M.; Chen, G. F.; Gong, M. Q.; Wu, J. F.

    2014-01-01

    In the high temperature superconducting (HTS) cable system, liquid nitrogen is usually chosen to be the coolant because of its low saturation temperature and large latent heat of vaporization. Thus, it is very important for superconducting cables that the liquid nitrogen temperature field keeps stable. However, the cryostat is usually made of flexible corrugated pipes and multi-layer insulation materials. The characteristics (e.g. wave pitch and wave depth) of corrugated pipes may have an effect on the heat exchange between cable and liquid nitrogen, even the whole temperature field of liquid nitrogen. In this paper, a two-dimensional model for 30 m long HTS cable has been modified to analyze the effect of corrugated characteristics on the temperature field of liquid nitrogen. The liquid nitrogen temperature difference between the outlet and the inlet of passage gradually increases as the wave pitch of the corrugated tube decreases and the wave depth increases.

  11. Calculation of AC loss in two-layer superconducting cable with equal currents in the layers

    Science.gov (United States)

    Erdogan, Muzaffer

    2016-12-01

    A new method for calculating AC loss of two-layer SC power transmission cables using the commercial software Comsol Multiphysics, relying on the approach of the equal partition of current between the layers is proposed. Applying the method to calculate the AC-loss in a cable composed of two coaxial cylindrical SC tubes, the results are in good agreement with the analytical ones of duoblock model. Applying the method to calculate the AC-losses of a cable composed of a cylindrical copper former, surrounded by two coaxial cylindrical layers of superconducting tapes embedded in an insulating medium with tape-on-tape and tape-on-gap configurations are compared. A good agreement between the duoblock model and the numerical results for the tape-on-gap cable is observed.

  12. Design of a 30 m long 1 kA 10 kV YBCO cable

    Energy Technology Data Exchange (ETDEWEB)

    Rostila, L [Institute of Electromagnetics, Tampere University of Technology, PO Box 692, FIN-33101 Tampere (Finland); Lehtonen, J [Institute of Electromagnetics, Tampere University of Technology, PO Box 692, FIN-33101 Tampere (Finland); Masti, M [Institute of Electromagnetics, Tampere University of Technology, PO Box 692, FIN-33101 Tampere (Finland); Lallouet, N [Nexas France, rue Mozart 4-10, 92587 Clichy (France); Saugrain, J-M [Nexas France, rue Mozart 4-10, 92587 Clichy (France); Allais, A [Nexans Deutschland Industries GmbH and Co. KG, Kabelkamp 20, D-30179 Hannover (Germany); Schippl, K [Nexans Deutschland Industries GmbH and Co. KG, Kabelkamp 20, D-30179 Hannover (Germany); Schmidt, F [Nexans Deutschland Industries GmbH and Co. KG, Kabelkamp 20, D-30179 Hannover (Germany); Balog, G [Nexans Norway, PO Box 6450, Etterstad, N-0605, Oslo, Norway (Norway); Marot, G [Air Liquide DTA, 2 rue de Clemenciere BP15, 38360 Sassenage (France); Ravex, A [Air Liquide DTA, 2 rue de Clemenciere BP15, 38360 Sassenage (France); Usoskin, A [European High Temperature Superconductors Gmbh and Co. KG, Windausweg 2, 37037 Goettingen (Germany); Goemoery, F [Institute of Electrical Engineering, Slovak Academy of Sciences, Dubravska cesta 9, 84104 Bratislava (Slovakia); Klincok, B [Institute of Electrical Engineering, Slovak Academy of Sciences, Dubravska cesta 9, 84104 Bratislava (Slovakia); Souc, J [Institute of Electrical Engineering, Slovak Academy of Sciences, Dubravska cesta 9, 84104 Bratislava (Slovakia); Freyhardt, H C [Institute of Materialphysic, University of Goettingen, Friedrich-Hund-Platz 1, D-37077 Goettingen (Germany)

    2006-04-15

    In this paper a 30 m long one-phase coaxial YBCO cable with 1 kA transport current and 10 kV operating voltage was designed for the Super3C project to check the feasibility of YBCO tapes for low-loss cables. The final design incorporates cryogenic, mechanical and electromagnetic aspects. The electromagnetic losses during normal operation must be minimized. The cryogenic design must also take into account the generation of heat during short circuit conditions. Mechanical restrictions set the minimum gaps between the coated conductor tapes and the minimum lay angles in order to make the cabling feasible and to enable handling of the cable. The design of the electric insulation should be according to the international standard as far as applicable. The final design has to take into account all of the above restrictions.

  13. Utilization of two-way multicore cables and comparison of various electrode configurations in electrical prospecting; Denki tansa ni okeru sohokogata tashin cable no riyo to kakushu dekyoku haichi no hikaku

    Energy Technology Data Exchange (ETDEWEB)

    Takakura, S. [Geological Survey of Japan, Tsukuba (Japan); Matsushima, J. [The University of Tokyo, Tokyo (Japan). Faculty of Engineering

    1996-10-01

    For more precise electrical prospecting, the new multicore cable was developed to allow high-density measurement by conventional equipment. Since conventional multicore cables are inferior in cost, length and weight, the new cable is composed of an n-conductor cable, two n-conductor male connectors and n lead wires. For connection of the multi-conductor cable and lead wires, cable sheath is peeled at n points at specific intervals. Sheath of the k-th conductor is peeled at k-th point from the terminal, and restored for insulation after connection of the conductor and lead wire. The male connectors are attached to the both ends of the multi-conductor cable. Since this two-way type cable can be used at every end, the measuring equipment can measure at one divisional point after another of a long measuring line while shifting the equipment from one point to another. All measurements are perfected only with two short cables. Resistivities were successfully measured along the long measuring line of 480m long with 97 electrodes arranged at intervals of 5m. Various electrode configurations were also compared. 1 ref., 4 figs., 2 tabs.

  14. Cable ampacity. A Finnish perspective

    Energy Technology Data Exchange (ETDEWEB)

    Millar, R.J.; Lehtonen, M.

    2006-07-01

    This report is primarily the practical application of a new method to calculate cable conductor temperatures in real time. A brief summary of various thermal parameter measurements in southern Finland is provided, an algorithm to compute cable temperatures in real time when both moisture migration and overall moisture content change are occurring is outlined, potential outcomes of extended loading are demonstrated, installation configurations are compared, steady-state and cyclic ratings are given for HV and MV installations, and emergency loading scenarios are evaluated. A more rational approach to cable rating in Finnish conditions is established. Conservative transient-based rating tends to give back the ampacity that might be lost due to worst possible environmental conditions for installed cables. Nevertheless, it is suggested that MV cables be derated by 20 % from their nominal catalogue ratings. orig.)

  15. Length of a Hanging Cable

    Directory of Open Access Journals (Sweden)

    Eric Costello

    2011-01-01

    Full Text Available The shape of a cable hanging under its own weight and uniform horizontal tension between two power poles is a catenary. The catenary is a curve which has an equation defined by a hyperbolic cosine function and a scaling factor. The scaling factor for power cables hanging under their own weight is equal to the horizontal tension on the cable divided by the weight of the cable. Both of these values are unknown for this problem. Newton's method was used to approximate the scaling factor and the arc length function to determine the length of the cable. A script was written using the Python programming language in order to quickly perform several iterations of Newton's method to get a good approximation for the scaling factor.

  16. Cable Bacteria in Freshwater Sediments

    DEFF Research Database (Denmark)

    Risgaard-Petersen, Nils; Kristiansen, Michael; Frederiksen, Rasmus

    2015-01-01

    In marine sediments cathodic oxygen reduction at the sediment surface can be coupled to anodic sulfide oxidation in deeper anoxic layers through electrical currents mediated by filamentous, multicellular bacteria of the Desulfobulbaceae family, the so-called cable bacteria. Until now, cable...... marine cable bacteria, with the genus Desulfobulbus as the closest cultured lineage. The results of the present study indicate that electric currents mediated by cable bacteria could be important for the biogeochemistry in many more environments than anticipated thus far and suggest a common evolutionary...... bacteria have only been reported from marine environments. In this study, we demonstrate that cable bacteria also occur in freshwater sediments. In a first step, homogenized sediment collected from the freshwater stream Giber Å, Denmark, was incubated in the laboratory. After 2 weeks, pH signatures...

  17. Photonic-powered cable assembly

    Science.gov (United States)

    Sanderson, Stephen N.; Appel, Titus James; Wrye, IV, Walter C.

    2013-01-22

    A photonic-cable assembly includes a power source cable connector ("PSCC") coupled to a power receive cable connector ("PRCC") via a fiber cable. The PSCC electrically connects to a first electronic device and houses a photonic power source and an optical data transmitter. The fiber cable includes an optical transmit data path coupled to the optical data transmitter, an optical power path coupled to the photonic power source, and an optical feedback path coupled to provide feedback control to the photonic power source. The PRCC electrically connects to a second electronic device and houses an optical data receiver coupled to the optical transmit data path, a feedback controller coupled to the optical feedback path to control the photonic power source, and a photonic power converter coupled to the optical power path to convert photonic energy received over the optical power path to electrical energy to power components of the PRCC.

  18. Special MV cable for long stator winding application Transrapid Shanghai; Cable MT special pour enroulements de stator long sur le train Transrapid de Shanghai

    Energy Technology Data Exchange (ETDEWEB)

    Buethe, H.; Le Dren, S.; Steinbrink, D.; Zamzow, P.E. [Nexans Industries GmbH and Co KG (Germany)

    2003-07-01

    The long stator winding of the Transrapid represents the most innovative high speed MAGLEV technology application for a special rubber MV cable with formerly unequaled mechanical and electrical requirements. For the first time, we are able to provide details about this special MV cable solution, using high quality rubber compounds for conductor insulation and semiconductive outer sheath with gliding coating for the long stator winding of the Transrapid Shanghai propulsion system, and to report that the high demands and specifications of the whole system were fulfilled. (authors)

  19. The numerical study of the influence of rheological parameters stratified flows characteristics in cable dies

    Science.gov (United States)

    Kozitsyna, M. V.; Trufanova, N. M.

    2017-01-01

    Today the process of coextrusion is the most technological in the cable production with cross-linked polyethylene, composed of two or more layers of polymeric insulation. Since the covering technology is a simultaneous imposition of all necessary layers (two semiconducting shields on the insulation and conductor and one - on insulation), the main focus of this study is the analysis of significance of various factors influence on stratified flows characteristics. This paper has considered the flow of two abnormally viscous liquids in the cable head. The problem has been solved through a three-dimensional statement by applying the finite element method in the Ansys software package. The influence has been estimated by varying the rheological properties of materials to create all necessary layers thickness.

  20. Simplified models for estimating isothermal operating characteristics of food extruders.

    Science.gov (United States)

    Levine, L; Rockwood, J

    1985-09-01

    A model of isothermal food extruder performance is described. Inferences about alternative extruder screw designs and their performance are drawn from the model. The model suggests that thread depth or diameter compression screws are superior in performance to a pitch compression screw. The advantage gained from using diameter compression screws is paid for with significantly higher rates of energy dissipation. The use of the model to characterize screws having both a compression zone and metering zone is described.

  1. Research for the Cable Layout Way of the Bypass Operation System in Agricultural Power Supply Network

    Science.gov (United States)

    Niu, Jie; Li, Jinliang; Zou, Dehua; Yang, Qi; Li, Xu; Yan, Yu; Li, Tang

    2017-05-01

    Non-blackout working of agricultural power supply network is significant to shorten the outage time, decrease the outage loss, and improve the supply reliability and safety. It is impossible to hang the wire rope first and then suspend the cable because of the poor bearing ability of the pole in agricultural power supply network. A kind of new cable arrangement way, its matching tools and the flexible cable that can bear the tension by itself are needed to be put forward and developed. It is necessary to calculate the electric field intensity of the flexible cable to verify that the electric field intensity meets the insulation demand. In this new design, the fiber layer is added into the flexible cable and its maximum tension force is measured to reach to 4000 N. Based on the features of live working in the agricultural power supply network, the new layout way of the cable is proposed; the matching tools and the new flexible cable that can bear the tension by itself are developed as well in this paper. All of the research achievements can give references for the live working of the agricultural power supply network.

  2. Theoretical Investigation on Skin Effect Factor of Conductor in Power Cables

    Science.gov (United States)

    Suzuki, Hiroshi; Kanaoka, Mamoru

    This paper describes a newly-derived theoretical equation on the skin effect factor of power cables, and its application to large-size OF and XLPE cables with segmental conductors, including insulated wires. The skin effect factors calculated with the new equation were fit very well to measurements in wide range conductor sizes. In the new equation, the important factor which characterizes the skin effect of segmental conductors is the `equivalent conductivity ratio' ν defined by the ratio of longitudinal conductivity in axial direction of conductor to conductivity of conductor wires. Since the obtained ratio ν in XLPE cable was three times greater than that in OF cable, the larger longitudinal eddy current passing from a wire to another increased the eddy current loss in conductor, which increased the conductor loss of XLPE cable. The new equation enables us to investigate quantitatively the dominant loss component affecting the skin effect factor. Then, the skin effect factors and coefficients for OF and XLPE cables were investigated with the new equation. It was revealed that the best number of separation, in which the skin effect became minimum, existed in OF and XLPE cables with segmental conductors. In addition, it was confirmed that the skin effect coefficients ks1 calculated with the new equation were consistent well with those used in JCS.

  3. Gap Filling Ceramic Insulating Putty for High Field Magnets

    Science.gov (United States)

    Rice, J. A.; Rice, H. M.

    2008-03-01

    Gaps between the A15 superconducting cable and its supports can sometimes occur requiring expensive rework of the support or filling with a non-optimal material. Recently, a new ceramic putty has been developed that can fill these gaps to fully support the superconducting cable. This ceramic material can withstand the extreme temperature differences between the high temperature heat treatment and the cryogenic operation. Significant performance improvements have been made that will enable the insulating putty to be used in some accelerator magnet systems. Processing methods will be discussed as well as strength and thermal data.

  4. Cable Bacteria in Freshwater Sediments.

    Science.gov (United States)

    Risgaard-Petersen, Nils; Kristiansen, Michael; Frederiksen, Rasmus B; Dittmer, Anders Lindequist; Bjerg, Jesper Tataru; Trojan, Daniela; Schreiber, Lars; Damgaard, Lars Riis; Schramm, Andreas; Nielsen, Lars Peter

    2015-09-01

    In marine sediments cathodic oxygen reduction at the sediment surface can be coupled to anodic sulfide oxidation in deeper anoxic layers through electrical currents mediated by filamentous, multicellular bacteria of the Desulfobulbaceae family, the so-called cable bacteria. Until now, cable bacteria have only been reported from marine environments. In this study, we demonstrate that cable bacteria also occur in freshwater sediments. In a first step, homogenized sediment collected from the freshwater stream Giber Å, Denmark, was incubated in the laboratory. After 2 weeks, pH signatures and electric fields indicated electron transfer between vertically separated anodic and cathodic half-reactions. Fluorescence in situ hybridization revealed the presence of Desulfobulbaceae filaments. In addition, in situ measurements of oxygen, pH, and electric potential distributions in the waterlogged banks of Giber Å demonstrated the presence of distant electric redox coupling in naturally occurring freshwater sediment. At the same site, filamentous Desulfobulbaceae with cable bacterium morphology were found to be present. Their 16S rRNA gene sequence placed them as a distinct sister group to the known marine cable bacteria, with the genus Desulfobulbus as the closest cultured lineage. The results of the present study indicate that electric currents mediated by cable bacteria could be important for the biogeochemistry in many more environments than anticipated thus far and suggest a common evolutionary origin of the cable phenotype within Desulfobulbaceae with subsequent diversification into a freshwater and a marine lineage.

  5. Complete Fiber/Copper Cable Solution for Long-Term Temperature and Pressure Measurement in Supercritical Reservoirs and EGS Wells

    Energy Technology Data Exchange (ETDEWEB)

    Pastouret, Alan [Draka Cableteq USA, Inc., North Dighton, MA (United States); Gooijer, Frans [Draka Cableteq USA, Inc., North Dighton, MA (United States); Overton, Bob [Draka Cableteq USA, Inc., North Dighton, MA (United States); Jonker, Jan [Draka Cableteq USA, Inc., North Dighton, MA (United States); Curley, Jim [Draka Cableteq USA, Inc., North Dighton, MA (United States); Constantine, Walter [Draka Cableteq USA, Inc., North Dighton, MA (United States); Waterman, Kendall Miller [Draka Cableteq USA, Inc., North Dighton, MA (United States)

    2015-11-13

    High Temperature insulated wire and optical fiber cable is a key enabling technology for the Geothermal Technologies Program (GTP). Without insulated electrical wires and optical fiber, downhole temperature and pressure sensors, flow meters and gauges cannot communicate with the surface. Unfortunately, there are currently no insulated electrical wire or fiber cable constructions capable of surviving for extended periods of deployment in a geothermal well (240-325°C) or supercritical (374°C) reservoir. This has severely hindered engineered reservoir creation, management and utilization, as hot zones and cool water intrusions cannot be understood over time. The lack of a insulated electrical wire and fiber cable solution is a fundamental limitation to the viability of this energy source. The High Temperature Downhole Tools target specification is development of tools and sensors for logging and monitoring wellbore conditions at depths of up to 10,000 meters and temperatures up to 374oC. It well recognized in the industry that no current electronic or fiber cable can be successfully deployed in a well and function successfully for more a few days at temperatures over 240oC. The goal of this project was to raise this performance level significantly. Prysmian Group’s objective in this project was to develop a complete, multi-purpose cable solution for long-term deployment in geothermal wells/reservoirs that can be used with the widest variety of sensors. In particular, the overall project objective was to produce a manufacturable cable design that can perform without serious degradation: • At temperatures up to 374°C; • At pressures up to 220 bar; • In a hydrogen-rich environment; and • For the life of the well (> 5 years). This cable incorporates: • Specialty optical fibers, with specific glass chemistry and high temperature and pressure protective coatings for data communication and distributed temperature and pressure sensing, and • High

  6. 10BASE5 Ethernet Cable & Vampire Tap

    CERN Multimedia

    1983-01-01

    10BASE5 Thick Ethernet Cable, 10Mbit/sec. In the 1980s and early 1990's, Ethernet became more popular and provided a much faster data transmission rate. This cable is one of the first ethernet cables from 1983, a thick, bulky affair. Computers were attached via "Vampire Taps" which were connectors screwed straight through the shielding of the cable.

  7. 14 CFR 27.1365 - Electric cables.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Electric cables. 27.1365 Section 27.1365... STANDARDS: NORMAL CATEGORY ROTORCRAFT Equipment Electrical Systems and Equipment § 27.1365 Electric cables. (a) Each electric connecting cable must be of adequate capacity. (b) Each cable that would...

  8. Cable Television, Market Power and Regulation.

    Science.gov (United States)

    Thorpe, Kenneth E.

    The goals of this dissertation are to provide an empirical examination of the impact of competing technologies on cable television firms and to document existing pricing behavior in the cable and pay programming industry. The introduction provides a brief overview of the cable television industry, including the impact of cable on federal policy…

  9. Cable Television: Citizen Participation in Planning.

    Science.gov (United States)

    Yin, Robert K.

    The historical background of citizen participation in local affairs and its relevance at the onset of community concern about cable television are briefly discussed in this report. The participation of citizens, municipal officials, and cable operators in laying the groundwork for a cable system as well as the pros and cons of cable television as…

  10. 14 CFR 25.689 - Cable systems.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Cable systems. 25.689 Section 25.689... STANDARDS: TRANSPORT CATEGORY AIRPLANES Design and Construction Control Systems § 25.689 Cable systems. (a) Each cable, cable fitting, turnbuckle, splice, and pulley must be approved. In addition— (1) No...

  11. Partial Discharge Characteristics in the Course of Aging within XLPE Insulation

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    This paper deals with the experimental study on the correlation between partial discharge (PD) characteristic parameters and corresponding aging degree of insulation in the course of the aging within cross-linked polyethylene (XLPE) insulation. The aging tests were performed on a section of 10 kV transmission cable by means of water needle method. The PD macroscopic characteristic parameters were found to be significantly dependent on the corresponding aging degree of insulation in the course of aging of XLPE, and different kind of aging stage has different characteristics. Beside, there are similar regularity but different PD amplitude in the course of aging of XLPE insulation in different electrolyte, and their insulation life is different. Therefore, according to the changing regularity of the PD macroscopic characteristic parameters within XLPE insulation judging the aging degree of XLPE insulation will be an effective method.

  12. Superconducting cable connections and methods

    Energy Technology Data Exchange (ETDEWEB)

    van der Laan, Daniel Cornelis

    2017-09-05

    Superconducting cable connector structures include a terminal body (or other structure) onto which the tapes from the superconducting cable extend. The terminal body (or other structure) has a diameter that is sufficiently larger than the diameter of the former of the superconducting cable, so that the tapes spread out over the outer surface of the terminal body. As a result, gaps are formed between tapes on the terminal body (or other structure). Those gaps are filled with solder (or other suitable flowable conductive material), to provide a current path of relatively high conductivity in the radial direction. Other connector structures omit the terminal body.

  13. Thermal analysis of underground power cable system

    Science.gov (United States)

    Rerak, Monika; Ocłoń, Paweł

    2017-10-01

    The paper presents the application of Finite Element Method in thermal analysis of underground power cable system. The computations were performed for power cables buried in-line in the ground at a depth of 2 meters. The developed mathematical model allows determining the two-dimensional temperature distribution in the soil, thermal backfill and power cables. The simulations studied the effect of soil and cable backfill thermal conductivity on the maximum temperature of the cable conductor. Also, the effect of cable diameter on the temperature of cable core was studied. Numerical analyses were performed based on a program written in MATLAB.

  14. XLPE电缆电树枝二次生长特性分析%Analysis on Secondary Growth Characteristics of Electrical Trees in XLPE Cable

    Institute of Scientific and Technical Information of China (English)

    周湶; 陈仕军; 廖瑞金

    2009-01-01

    In order to study the growth characteristics of electrical trees in XLPE cable under secondary applied volt- age, a short cable metal needle defect test device is adopted to study the growth characteristics of the new trees after the electrical trees in XLPE cable under the action of the voltage of 12 kV are influenced by secondary applied volt- age (15 kV). The research results show that influenced by secondary applied voltage and voltage increase rate, there will be a peculiar "bush-branch" electrical tree in XLPE cable insulation layer and the new trees under secondary ap- plied voltage have the characteristics of short initiation time, fast growth rate and narrow discharge channel, etc, which shows that secondary applied voltage has a great effect on the secondary initiation and growth of electrical trees in XLPE cable and it is an important factor of accelerating cable aging and breakdown.

  15. The development of ShortWatch, a novel overtemperature or mechanical damage sensing technology for wires or cables. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Watkins, Ken; Morris, Jack; Wong, C.P.; Luo, Shijian

    2001-09-07

    'ShortWatch' is a patented technology which for the first time offers electrical wire/cable products providing real-time, 'in-situ' (1) condition monitoring that warns of insulation damage before an electrical fault occurs, (2) assessment of the ability to perform in a Design Basis event, (3) distributed sensor warning of overtemperature, and (4) insulation leakage measurement capability providing arc sensing and a reliable tool for wire age prediction.

  16. Static and Dynamic Characteristics of a Long-Span Cable-Stayed Bridge with CFRP Cables

    Directory of Open Access Journals (Sweden)

    Xu Xie

    2014-06-01

    Full Text Available In this study, the scope of CFRP cables in cable-stayed bridges is studied by establishing a numerical model of a 1400-m span of the same. The mechanical properties and characteristics of CFRP stay cables and of a cable-stayed bridge with CFRP cables are here subjected to comprehensive analysis. The anomalies in the damping properties of free vibration, nonlinear parametric vibration and wind fluctuating vibration between steel cables and CFRP cables are determined. The structural stiffness, wind resistance and traffic vibration of the cable-stayed bridge with CFRP cables are also analyzed. It was found that the static performances of a cable-stayed bridge with CFRP cables and steel cables are basically the same. The natural frequencies of CFRP cables do not coincide with the major natural frequencies of the cable-stayed bridge, so the likelihood of CFRP cable-bridge coupling vibration is minuscule. For CFRP cables, the response amplitudes of both parametric vibration and wind fluctuating vibration are smaller than those of steel cables. It can be concluded from the research that the use of CFRP cables does not change the dynamic characteristics of the vehicle-bridge coupling vibration. Therefore, they can be used in long-span cable-stayed bridges with an excellent mechanical performance.

  17. Electromagnetic Transients in Power Cables

    DEFF Research Database (Denmark)

    Silva, Filipe Faria Da; Bak, Claus Leth

    of the method. The chapter continues by analysing the frequency-spectrums of cable-based networks which have lower resonance frequencies than usual because of the larger capacitance of the cables. At the same time, a technique that may help save time when plotting the frequency spectrum of a network is proposed...... typically used for the screens of cables (both-ends bonding and cross-boding) and also presents methods that can be used to estimate the maximum current of a cable for different types of soils, i.e. thermal calculations. The end of the chapter introduces the shunt reactor, which is an important element....... It is true that in many cases, software is used to run simulations, and the reader may be tempted to think that only those designing the software need to know how to use modal theory. However, several phenomena require at least a minimum knowledge of the topic and for that reason, the book provides...

  18. Motility of electric cable bacteria

    DEFF Research Database (Denmark)

    Bjerg, Jesper Tataru; Damgaard, Lars Riis; Holm, Simon Agner

    2016-01-01

    Cable bacteria are filamentous bacteria that electrically couple sulfide oxidation and oxygen reduction at centimeter distances, and observations in sediment environments have suggested that they are motile. By time-lapse microscopy, we found that cable bacteria used gliding motility on surfaces...... with a highly variable speed of 0.50.3 ms1 (meanstandard deviation) and time between reversals of 155108 s. They frequently moved forward in loops, and formation of twisted loops revealed helical rotation of the filaments. Cable bacteria responded to chemical gradients in their environment, and around the oxic......-anoxic interface, they curled and piled up, with straight parts connecting back to the source of sulfide. Thus, it appears that motility serves the cable bacteria in establishing and keeping optimal connections between their distant electron donor and acceptors in a dynamic sediment environment....

  19. Insulation Characteristics of Bushing Shed at Cryogenic Temperature

    Science.gov (United States)

    Kim, W. J.; Kim, Y. J.; Kim, S. H.

    2014-05-01

    In the development of high-Tc superconducting(HTS) devices, the bushing for HTS devices (HTS bushing) is the core technology, the need to because of supply high voltage to the cable or the winding of the transformer. The lower part of the bushing is exposed to the liquid nitrogen (LN2), and it has many sheds. In particular, the insulation body with sheds and electrical insulation at cryogenic temperature have attracted a great deal of interest from the view point of the size, weight and efficiency of bushing. This study has mainly investigated the shed and insulation body by comparing glass fiber reinforced plastics (GFRP) in LN2. We investigated the surface discharge characteristics according to insulating materials, width and height of the shed.

  20. Study on long-term irradiation aging of electrical cables (The VEILLE program)

    Energy Technology Data Exchange (ETDEWEB)

    Carlin, F.; Attal, M.; Gaussens, G. [and others

    1995-04-01

    The VEILLE program (French acronym for study on long-term irradiation aging of electrical cables) was implemented in 1988 by the Institute of Protection and Nuclear Safety (IPSN) in collaboration with the US Nuclear Regulatory Commission (NRC) for a period of six years. It is intended to validate the assumptions put forward as regards aging of electrical cables and to develop criteria for early detection of degradation likely to lead to functional failures. The tests were carried out partly at the Sandia National Laboratories in the United States, partly in France in the CIS bio international Laboratories at the Saclay Nuclear Research Centre. The study focused on the radiation effects from cobalt 60 on electrical cables made up of various polymers for two temperatures and at various dose rates. Other tests were also performed using a device laid under water in the OSIRIS reactor pool at Saclay to test cables under irradiation and temperature conditions close to those found in nuclear power plant operation. Subsequently the aged cables were subjected to containment accident conditions (irradiation and thermodynamic profile) in order to show any degradation due to aging. The study showed the significant effect of radiation doses on EPR and EPDM cable insulations as well as synergy between radiation dose rates and temperature on the mechanical properties of the Hypalon sheath. Correlation between the mechanical properties and the function of cables is difficult to establish as electrical characteristics are preserved whatever the type of mechanical degradation observed. Finally, the performance of electrical cables after an accident remains a key criterion to define the materials likely to be used when manufacturing cables intended to ensure safety functions.

  1. ELECTROSTATIC PROCESSES IN POWER CABLES

    Directory of Open Access Journals (Sweden)

    G.V. Bezprozvannych

    2013-09-01

    Full Text Available Observation of contact electrification of power cable samples is made. It is revealed that the contact potential difference and the capacity formed under separation of free charges on the surfaces of the contacting materials depend on cable design, applied materials, and inspection schemes. Time series of capacity drift and dielectric loss tangent caused by instability of triboelectric charging of the contacting surfaces are presented.

  2. Bio rapid prototyping by extruding/aspirating/refilling thermoreversible hydrogel

    Energy Technology Data Exchange (ETDEWEB)

    Iwami, K; Noda, T; Ishida, K; Umeda, N [Department of Mechanical Systems and Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Nakacho, Koganei, Tokyo 184-8588 (Japan); Morishima, K [Department of Bio-Applications and Systems Engineering, Tokyo University of Agriculture and Technology, 2-24-16 Nakacho, Koganei, Tokyo 184-8588 (Japan); Nakamura, M, E-mail: k_iwami@cc.tuat.ac.j [Department of Life Sciences and Bioengineering, University of Toyama, 3190 Gofuku, Toyama, 930-8555 (Japan)

    2010-03-15

    This paper reports a method for rapid prototyping of cell tissues, which is based on a system that extrudes, aspirates and refills a mixture of cells and thermoreversible hydrogel as a scaffold. In the extruding mode, a cell-mixed scaffold solution in the sol state is extruded from a cooled micronozzle into a temperature-controlled substrate, which keeps the scaffold in the gel state. In the aspiration mode, the opposite process is performed by Bernoulli suction. In the refilling mode, the solution is extruded into a groove created in the aspiration mode. The minimum width of extruded hydrogel pattern is 114 +- 15 mum by employing a nozzle of diameter 100 mum, and that of aspirated groove was 355 +- 10 mum using a 500 mum-diameter nozzle. Gum arabic is mixed with the scaffold solution to avoid peeling-off of the gel pattern from the substrate. Patterning of Sf-9 cell tissue is demonstrated, and the stability of the patterned cell is investigated. This system offers a procedure for rapid prototyping and local modification of cell scaffolds for tissue engineering.

  3. Power quality problems caused by termites on 138-kV underground cables

    Directory of Open Access Journals (Sweden)

    Romeu Fuscaldi

    2011-07-01

    Full Text Available This paper discusses problems found in the operation of underground cables in the transmission system of CEMIG, with emphasis on insulation failures caused by termites. This problem has been the source of many scheduled and nonscheduled interruptions in later years, leading to significant maintenance costs. Experience with current practices designed to detect and prevent this failure mode is described. It is argued that new procedures are needed for improved on-line, pre-failure detection. Test improvement will hopefully contribute to increase the lifetime of underground cables currently in use, as well as to reduce maintenance costs.

  4. Brookhaven superconducting cable test facility

    Energy Technology Data Exchange (ETDEWEB)

    Forsyth, E.B.; Gibbs, R.J.

    1976-08-17

    Construction has started on an outdoor testing station for flexible ac superconducting power transmission cables. It is intended to serve as an intermediate step between laboratory-scale experiments and qualification testing of prototype-scale cables. The permanent equipment includes a 500 W supercritical helium refrigerator using a screw compressor and multistage turbine expanders. Helium storage for 250,000 cu ft of helium at 250 psi is provided. Initially, the cables will be tested in a horizontal cryostat some 250 ft long. High-voltage 60 Hz tests will be performed with the cable in a series resonant mode with a maximum line to ground capability of 240 kV, this is adequate for a 138 kV system design. Impulse testing up to about 650 kV is planned. The cable conductor will be energized by current transformers, initially at about 4 kA and later up to fault levels of 40 kA. The refrigerator is now at the site and testing on a dummy load will commence in the Fall of 1976. The cryostat will be installed in 1977 followed about a year later by the first cable tests.

  5. Enhanced Electrical Conductivity in Extruded Single-Wall Carbon Nanotube Wires from Modified Coagulation Parameters and Mechanical Processing.

    Science.gov (United States)

    Bucossi, Andrew R; Cress, Cory D; Schauerman, Christopher M; Rossi, Jamie E; Puchades, Ivan; Landi, Brian J

    2015-12-16

    Single-wall carbon nanotubes (SWCNTs) synthesized via laser vaporization have been dispersed using chlorosulfonic acid (CSA) and extruded under varying coagulation conditions to fabricate multifunctional wires. The use of high purity SWCNT material based upon established purification methods yields wires with highly aligned nanoscale morphology and an over 4× improvement in electrical conductivity over as-produced SWCNT material. A series of eight liquids have been evaluated for use as a coagulant bath, and each coagulant yielded unique wire morphology based on its interaction with the SWCNT-CSA dispersion. In particular, dimethylacetamide as a coagulant bath is shown to fabricate highly uniform SWCNT wires, and acetone coagulant baths result in the highest specific conductivity and tensile strength. A 2× improvement in specific conductivity has been measured for SWCNT wires following tensioning induced both during extrusion via increased coagulant bath depth and during solvent evaporation via mechanical strain, over that of as-extruded wires from shallower coagulant baths. Overall, combination of the optimized coagulation parameters has yielded acid-doped wires with the highest reported room temperature electrical conductivities to date of 4.1-5.0 MS/m and tensile strengths of 210-250 MPa. Such improvements in bulk electrical conductivity can impact the adoption of metal-free, multifunctional SWCNT materials for advanced cabling architectures.

  6. Insulating and sheathing materials of electric and optical cables - Common test methods - Part 5-1: Methods specific to filling compounds - Drop-point - Separation of oil - Lower temperature brittleness - Total acid number - Absence of corrosive components - Permittivity at 23 °C - DC resistivity at 23 °C and 100 °C

    CERN Document Server

    International Electrotechnical Commission. Geneva

    2004-01-01

    Specifies the test methods for filling compounds of electric cables used with telecommunication equipment. Gives the methods for drop-point, separation of oil, lower temperature brittleness, total acid number, absence of corrosive components, permittivity at 23 °C, d.c. resistivity at 23°C and 100°C.

  7. Technologies for Improved Reliability of Shielded Power Cable and Characterization of Capacitor Film Energy Density

    Science.gov (United States)

    Shu, Wen

    Partial Discharge (PD), a partial breakdown of insulation between high voltage electrodes, reduces cable reliability. Understanding electromagnetic propagation of PD-induced pulses in shielded power cable, including attenuation and dispersion, is essential to the application of PD diagnostics and, especially, PD location. Dispersion is caused by the transition of cable semicon-ducting layers (between the cable conductors and dielectric) from "resistive" at low frequency to "capacitive" at high frequency. Methods are presented to compute dispersion as a function of semiconducting material properties and evaluate the effect of dispersion on pulse characteristics (amplitude, shape, and width, etc.) as a function of distance propagated, the results of which are applied to investigate the effects of dispersion for PD detection and location. The location error induced by dispersion can be compensated from calibration. Electrochemical degradation of cable dielectrics, known as "water treeing", is one of the leading cause of premature failures in underground shielded power cable. Silane-based fluid has been used successfully for decades to rejuvenate HMWPE and XLPE dielectric cables to "cure" existing water trees and extend cable life. However the ability of the treatment to inhibit future water tree initiation is not known. A method for silane fluid treatment of un-aged cable insulation and semicon was developed based on the use of GC/MS to determine curing of the fluid within the dielectric. A wet electrical aging test at 5 kV/mm (127 V/mil) based on a sample which includes semicon electrodes on both sides of the XLPE insulation with a water electrode in contact with one semicon layer was used to age untreated samples, samples treated prior to the test, and samples treated at the mid-time of the test (3500 hrs). The result of aging is analyzed by microscopic examination to determine the number, length and types of water trees. The mechanism by which the silane

  8. Composite Behavior of a Novel Insulated Concrete Sandwich Wall Panel Reinforced with GFRP Shear Grids: Effects of Insulation Types

    Directory of Open Access Journals (Sweden)

    JunHee Kim

    2015-03-01

    Full Text Available A full-scale experimental program was used in this study to investigate the structural behavior of novel insulated concrete sandwich wall panels (SWPs reinforced with grid-type glass-fiber-reinforced polymer (GFRP shear connectors. Two kinds of insulation-expanded polystyrene (EPS and extruded polystyrene (XPS with 100 mm thickness were incased between the two concrete wythes to meet the increasing demand for the insulation performance of building envelope. One to four GFRP shear grids were used to examine the degree of composite action of the two concrete wythes. Ten specimens of SWPs were tested under displacement control subjected to four-point concentrated loads. The test results showed that the SWPs reinforced with GFRP grids as shear connectors developed a high degree of composite action resulting in high flexural strength. The specimens with EPS foam exhibited an enhanced load-displacement behavior compared with the specimens with XPS because of the relatively stronger bond between insulation and concrete. In addition, the ultimate strength of the test results was compared to the analytical prediction with the mechanical properties of only GRFP grids. The specimens with EPS insulation presented higher strength-based composite action than the ones with XPS insulation.

  9. Parametric Vibration and Vibration Reduction of Cables in Cable-stayed Space Latticed Structure

    Institute of Scientific and Technical Information of China (English)

    BAO Yan; ZHOU Dai; LIU Jie

    2008-01-01

    Mechanical model and vibration equation of a cable in cable-stayed sparse latticed structure (CSLS) under external axial excitation were founded. Determination of the mass lumps and natural frequencies supplied by the space latticed structure (SLS) was analyzed. Multiple scales method (MSM) was introduced to analyze the characteristics of cable's parametric vibration, and the precise time-integration method (PTIM) was used to solve vibration equation. The vibration behavior of a cable is closely relative to the frequency ratio of the cable and SLS. The cable's parametric vibration caused by the external axial excitation easily occurs if the frequency ratio of the cable and SLS is in a certain range, and the cable's vibration amplitude varies greatly even if the initial disturbance supplied by SLS changes a little. Furthermore, the mechanical model and vibration equation of the composite cable system consisting of main cables and assistant cables were studied. The parametric analysis such as the pre-tension level and arrangement of the assistant cables was carried out. Due to the assistant cables, the single-cable vibration mode can be transferred to the global vibration mode, and the stiffness and damping of the cable system are enhanced. The natural frequencies of the composite cable system with the curve line arrangement of assistant cables are higher than those with the straight-line arrangement and the former is more effective than the latter on the cable's vibration suppression.

  10. Extruder system and method for treatment of a gaseous medium

    Science.gov (United States)

    Silvi, Norberto; Perry, Robert James; Singh, Surinder Prabhjot; Balch, Gary Stephen; Westendorf, Tiffany Elizabeth Pinard

    2016-04-05

    A system for treatment of a gaseous medium, comprises an extruder having a barrel. The extruder further comprises a first inlet port, a second inlet port, and a plurality of outlet ports coupled to the barrel. The first inlet port is configured for feeding a lean sorbent, the second inlet port is configured for feeding a gaseous medium, and the plurality of outlet ports are configured for releasing a plurality of components removed from the gaseous medium. Further, the extruder comprises a plurality of helical elements coupled to a plurality of kneading elements, mounted on a shaft, and disposed within the barrel. The barrel and the plurality of helical and kneading elements together form an absorption unit and a desorption unit. The first and second inlet ports are formed in the absorption unit and the plurality of outlet ports are formed in the absorption and desorption units.

  11. Extruder system and method for treatment of a gaseous medium

    Energy Technology Data Exchange (ETDEWEB)

    Silvi, Norberto; Perry, Robert James; Singh, Surinder Prabhjot; Balch, Gary Stephen; Westendorf, Tiffany Elizabeth Pinard

    2016-04-05

    A system for treatment of a gaseous medium, comprises an extruder having a barrel. The extruder further comprises a first inlet port, a second inlet port, and a plurality of outlet ports coupled to the barrel. The first inlet port is configured for feeding a lean sorbent, the second inlet port is configured for feeding a gaseous medium, and the plurality of outlet ports are configured for releasing a plurality of components removed from the gaseous medium. Further, the extruder comprises a plurality of helical elements coupled to a plurality of kneading elements, mounted on a shaft, and disposed within the barrel. The barrel and the plurality of helical and kneading elements together form an absorption unit and a desorption unit. The first and second inlet ports are formed in the absorption unit and the plurality of outlet ports are formed in the absorption and desorption units.

  12. Stator insulation systems for medium voltage PWM drives fed motors

    Energy Technology Data Exchange (ETDEWEB)

    Gao, G.; Chen, W. [TECO-Westinghouse Motor Co., Round Rock, TX (United States)

    2005-07-01

    Adjustable speed drives (ASD) are commonly used in power electronics and control systems. It is estimated that more than 15 per cent of medium voltage motors are currently fed by such drives worldwide. A research project was conducted to examine the influence of medium voltage pulse width modulated (PWM) ASD on motor stator insulation systems. The findings, based on accelerated laboratory tests, have helped designers to improve the capabilities of the insulation system used for ASD-fed motors. Repetitive, high magnitude voltage spikes with fast rise time create significant stress on insulation systems. Gradual deterioration and premature failure of the motor insulation can result from surge voltages which generate surface discharges between phase windings/end windings, or partial discharges between stator turns. However, there is no industrial standard to evaluate motor insulation life under ASD-cable-motor conditions. Several material manufacturers have developed their own version of corona resistant material. However, the insulation life of ASD-fed motors does not depend solely on the raw materials. Rather, it depends on the complete insulation system, including the stator manufacturing process. In order to address this problem, TECO-Westinghouse Motor Company has developed special design criteria and manufacturing practices in order to reduce winding insulation temperature and to compensate for the additional heat generated by high frequency contents in the PWM voltage waveform. A patent pending new cooling system should reduce winding temperature by 15 to 20 degrees C. This paper presented design considerations for turn insulation, groundwall insulation, and a voltage stress grading system. A new thermal class H insulation system was also described. 6 refs., 2 tabs., 5 figs.

  13. Quality improvement of melt extruded laminar systems using mixture design.

    Science.gov (United States)

    Hasa, D; Perissutti, B; Campisi, B; Grassi, M; Grabnar, I; Golob, S; Mian, M; Voinovich, D

    2015-07-30

    This study investigates the application of melt extrusion for the development of an oral retard formulation with a precise drug release over time. Since adjusting the formulation appears to be of the utmost importance in achieving the desired drug release patterns, different formulations of laminar extrudates were prepared according to the principles of Experimental Design, using a design for mixtures to assess the influence of formulation composition on the in vitro drug release from the extrudates after 1h and after 8h. The effect of each component on the two response variables was also studied. Ternary mixtures of theophylline (model drug), monohydrate lactose and microcrystalline wax (as thermoplastic binder) were extruded in a lab scale vertical ram extruder in absence of solvents at a temperature below the melting point of the binder (so that the crystalline state of the drug could be maintained), through a rectangular die to obtain suitable laminar systems. Thanks to the desirability approach and a reliability study for ensuring the quality of the formulation, a very restricted optimal zone was defined within the experimental domain. Among the mixture components, the variation of microcrystalline wax content played the most significant role in overall influence on the in vitro drug release. The formulation theophylline:lactose:wax, 57:14:29 (by weight), selected based on the desirability zone, was subsequently used for in vivo studies. The plasma profile, obtained after oral administration of the laminar extruded system in hard gelatine capsules, revealed the typical trend of an oral retard formulation. The application of the mixture experimental design associated to a desirability function permitted to optimize the extruded system and to determine the composition space that ensures final product quality.

  14. Transport AC loss characteristics of a nine strand YBCO Roebel cable

    Science.gov (United States)

    Jiang, Zhenan; Badcock, R. A.; Long, N. J.; Staines, Mike; Thakur, K. P.; Lakshmi, L. S.; Wright, A.; Hamilton, K.; Sidorov, G. N.; Buckley, R. G.; Amemiya, Naoyuki; Caplin, A. D.

    2010-02-01

    Transport AC loss in a short length of 9/2 YBCO Roebel cable (nine 2 mm wide strands) is measured. The AC loss data are compared with those in a 5/2 YBCO Roebel cable (five 2 mm wide strands) as well as that in a single strand. All the strands composing the cables and the single strand are insulated and cut from the same stock material. The validity of the measurement method was reconfirmed by results at a range of frequencies. At a wide range of It/Ic, the normalized AC losses in the Roebel cable were around 6.2-6.7 times of those in the single strand. This is less than the nine times predicted for a tight bundle of nine conductors. The normalized transport AC losses in the 5/2 Roebel cable are much smaller than those in the 9/2 Roebel. This should be due to larger superposition of magnetic field in the 9/2 Roebel. The Ic of the 9/2 and 5/2 Roebel cables is determined by serial connection of the strands. This eliminates the effect where differing resistances in the current terminations cause uneven current sharing between strands when the strands are connected in parallel.

  15. Arc Testing of a Mockup Cable in a Simulated Space Radiation Environment

    Science.gov (United States)

    Ferguson, D. C.; Schneider, T. A.; Vaughn, J. A.

    2007-01-01

    A mockup cable was irradiated with electrons of 25-100 keV energy in a vacuum chamber. The m'ockup cable consisted of insulated wires on a kapton substrate, overlaid with a metallized teonex shield. Voltages induced on the wires and shield by the electron beam during irradiation were monitored, and voltage changes were used, along with video, to detect arcs due to the charge built-up in the cable. The cable was also cooled with liquid nitrogen to very low temperatures, to simulate cables kept in the dark for long periods of time. Arcing was common at fluences typical of long space missions. Occasionally an arc would occur some time after the electron beam was turned off. The conductivity of the wires and shield was monitored as a function of temperature, and behaved as expected, with lower conductivities at lower temperatures. Arcs from the wires and shield to ground and from the wires to the shield were measured. Sympathetic arcs were also seen, wherein an arc from the shield to ground or from the wires to ground was followed in a short period of time by another arc of a different type. Implications of these results for real cables on long space missions will be discussed, and recommendations given for arc mitigation.

  16. Quantitative analyses of extrudate swell for polymer nanocomposites

    Science.gov (United States)

    Wang, Kejian; Sun, Chongxiao

    2009-07-01

    The quantitative theory of extrudate swell for nanocomposite and pure polymer is significant either for optimum processing or for understanding their viscoelasticity. Based on Song's die swell theory for entangled polymers, one extrudate swell correlation with material properties and capillary parameters was developed for polymer melt and their nanocomposites when compensating reservoir entry effect. It was the first to find that the composite swell ratio can be the matrix swell ratio multiplied by the concentration shift factor. The factor is the functions of the shear field, filler content, filler internal structure and the surface state as well as the matrix properties. The quantitative model was well fitful for the five kinds of nanoomposites.

  17. Efficient Welding Fabrication of Extruded Aluminum Mat Panels

    Science.gov (United States)

    1991-09-01

    aged to produce the needle structure. This is confirmed by Enjo (Ref. 41) for 6063 - T5 alloy. However, as was shown by Dumolt (Ref. 38), increase in...According to Ref. 1, extrudability of 6061 alloy is rated as 60% of that of the standard 6063 alloy. The various combinations of properties and economics of...extrudability 2-17 TABLE 2-1. ExtrudabUilty of AI-Mg-SI Alloys A.A. Designation Grading Characteristics 6063 Low Strength Good finish, high extrusion

  18. Cryogenic Tests of 30 m Flexible Hybrid Energy Transfer Line with Liquid Hydrogen and Superconducting MgB2 Cable

    Science.gov (United States)

    Vysotsky, V. S.; Antyukhov, I. V.; Firsov, V. P.; Blagov, E. V.; Kostyuk, V. V.; Nosov, A. A.; Fetisov, S. S.; Zanegin, S. Yu.; Rachuk, V. S.; Katorgin, B. I.

    Recently we reported about first in the world test of 10 m hybrid energy transfer line with liquid hydrogen and MgB2 superconducting cable. In this paper we present the new development of our second hybrid energy transfer line with 30 m length. The flexible 30 m hydrogen cryostat has three sections with different types of thermal insulation in each section: simple vacuum superinsulation, vacuum superinsulation with liquid nitrogen shield and active evaporating cryostatting (AEC) system. We performed thermo-hydraulic tests of the cryostat to compare three thermo-insulating methods. The tests were performed at temperatures from 20 to 26 K, hydrogen flow from 100 to 450 g/s and pressure from 0.25 to 0.5 MPa. It was found that AEC thermal insulation practically eliminated completely heat transfer from room temperature to liquid hydrogen in the 10 m section. AEC thermal insulation method can be used for long superconducting power cables. High voltage current leads were developed as well. The current leads and superconducting MgB2 cable have been passed high voltage DC test up to 50 kV DC. Critical current of the cable at ∼21 K was ∼3500 A. The 30 m hybrid energy system developed is able to deliver up to 135 MW of chemical and electrical power in total.

  19. Optical Measurement of Cable and String Vibration

    Directory of Open Access Journals (Sweden)

    Y. Achkire

    1998-01-01

    Full Text Available This paper describes a non contacting measurement technique for the transverse vibration of small cables and strings using an analog position sensing detector. On the one hand, the sensor is used to monitor the cable vibrations of a small scale mock-up of a cable structure in order to validate the nonlinear cable dynamics model. On the other hand, the optical sensor is used to evaluate the performance of an active tendon control algorithm with guaranteed stability properties. It is demonstrated experimentally, that a force feedback control law based on a collocated force sensor measuring the tension in the cable is feasible and provides active damping in the cable.

  20. Cable condition monitoring using non-destructive and non-intrusive Fourier Transform Near Infrared (FT-NIR) spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Azizian, H. [NIR Technologies Inc., Oakville, Ontario (Canada); Benson, S. [RCM Technologies Canada, Mississauga, Ontario (Canada)

    2008-07-01

    The potential of using Fourier transform near infrared (FT-NIR) spectroscopy to monitor cable insulation condition and trend age-related degradation was investigated. The FT-NIR chemical finger-prints of PVC and XLPE cable insulation were significantly altered due to degradation resulting from irradiation and thermal aging. These spectral changes were correlated to critical property changes, i.e., average % elongation. The FT-NIR technique showed promise as an alternative to more traditional destructive chemical monitoring methods. The nuclear power industry is currently seeking cost-effective, non-destructive tools to support cable condition monitoring programs, now becoming recognized as essential to supporting plant life extensions and new builds. (author)

  1. Evaluation of Cable Harness Post-Installation Testing. Part B

    Science.gov (United States)

    King, M. S.; Iannello, C. J.

    2011-01-01

    The Cable Harness Post-Installation Testing Report was written in response to an action issued by the Ares Project Control Board (PCB). The action for the Ares I Avionics & Software Chief Engineer and the Avionics Integration and Vehicle Systems Test Work Breakdown Structure (WBS) Manager in the Vehicle Integration Office was to develop a set of guidelines for electrical cable harnesses. Research showed that post-installation tests have been done since the Apollo era. For Ares I-X, the requirement for post-installation testing was removed to make it consistent with the avionics processes used on the Atlas V expendable launch vehicle. Further research for the report involved surveying government and private sector launch vehicle developers, military and commercial aircraft, spacecraft developers, and harness vendors. Responses indicated crewed launch vehicles and military aircraft perform post-installation tests. Key findings in the report were as follows: Test requirements identify damage, human-rated vehicles should be tested despite the identification of statistically few failures, data does not support the claim that post-installation testing damages the harness insulation system, and proper planning can reduce overhead associated with testing. The primary recommendation of the report is for the Ares projects to retain the practice of post-fabrication and post-installation cable harness testing.

  2. Insulated Fiber Brush.

    Science.gov (United States)

    An insulated-strand fiber brush is provided for a DC motor /generator. The brush is comprised of a plurality of fiber segments which are insulated from one another near the contact surface of a rotor bar. In one embodiment, insulating spacers are fixed to a brush assembly and wear with the fibers, and in another embodiment insulation is provided by a separate shell. (Author)

  3. Analysis of Surveyor 3 television cable after residence on the moon

    Science.gov (United States)

    Gross, F. C.; Park, J. J.

    1972-01-01

    The Apollo 12 astronauts brought the Surveyor III television camera back from the moon in November 1969. Chemical analyses of a portion of television cable revealed changes in the glass fabric sleeve and in the wire insulation as a result of exposure to the lunar environment. Loss of volatile constituents from the glass fabric and a discoloration of the glass occurred. The Teflon layer on the wire showed a slight discoloration and possibly a slight change in its infrared spectrum. Both the polyimide layer and the Teflon layer of the wire insulation showed changes in tensile strength and elongation.

  4. The Design of Partial Discharge On-Line Monitoring System for XLPE Power Cable

    Directory of Open Access Journals (Sweden)

    Chen Rui-Long

    2013-09-01

    Full Text Available Partial discharge detection is an important means to assess the situation of XLPE power cable’s insulation. This study has developed an on-line monitoring system which applies to the medium voltage XLPE cable on partial discharge, described its working principle, components of hardware, software designing and program implementation in details. Through monitoring the partial discharge signal in grounding lines of the XLPE cable’s shield, the system integrated assess the situation of XLPE cable’s insulation. The results of running show that the system is stable and reliable.

  5. The modelling of counter-rotating twin screw extruders as reactors for single-component reactions

    NARCIS (Netherlands)

    Ganzeveld, K.J.; Capel, J.E.; Wal, D.J. van der; Janssen, L.P.B.M.

    1994-01-01

    Numerical models are useful to study the behaviour of the extruder as a polymerization reactor. With a correct numerical model a theoretical analysis of the influence of several reaction and extruder parameters can be made, the limitations of the use of the extruder reactor can be determined and the

  6. 78 FR 58520 - Extruded Rubber Thread From Malaysia; Notice of Amended Final Results of Antidumping Duty...

    Science.gov (United States)

    2013-09-24

    ... unliquidated entries of certain extruded rubber thread from Malaysia produced and/or exported by Heveafil, and... International Trade Administration Extruded Rubber Thread From Malaysia; Notice of Amended Final Results of... review of the antidumping duty order on extruded rubber thread from Malaysia.\\1\\ The period of review...

  7. The modelling of counter-rotating twin screw extruders as reactors for single-component reactions

    NARCIS (Netherlands)

    Ganzeveld, K.J.; Capel, J.E.; Wal, D.J. van der; Janssen, L.P.B.M.

    1994-01-01

    Numerical models are useful to study the behaviour of the extruder as a polymerization reactor. With a correct numerical model a theoretical analysis of the influence of several reaction and extruder parameters can be made, the limitations of the use of the extruder reactor can be determined and the

  8. Residence time distribution in twin-screw extruders.

    NARCIS (Netherlands)

    Jager, T.

    1992-01-01

    For the twin-screw extruders used in the food industry at short time high temperature processes the knowledge of their reactor properties is incomplete for mass- and heat flow. Therefore each process change such as: scale-up or product development requires a great number of measurements before an ac

  9. Residence time distribution in twin-screw extruders

    NARCIS (Netherlands)

    Jager, T.

    1992-01-01

    For the twin-screw extruders used in the food industry at short time high temperature processes the knowledge of their reactor properties is incomplete for mass- and heat flow. Therefore each process change such as: scale-up or product development requires a great number of measurements

  10. A consolidation based extruder model to explore GAME process configurations

    NARCIS (Netherlands)

    Willems, P.; Kuipers, N.J.M.; de Haan, A.B.

    2009-01-01

    A mathematical model from literature was adapted to predict the pressure profile and oil yield for canola in a lab-scale extruder. Changing the description of the expression process from filtration to consolidation significantly improved the performance and physical meaning of the model. The model

  11. Buckling of a beam extruded into highly viscous fluid

    Science.gov (United States)

    Gosselin, F. P.; Neetzow, P.; Paak, M.

    2014-11-01

    Inspired by microscopic Paramecia which use trichocyst extrusion to propel themselves away from thermal aggression, we propose a macroscopic experiment to study the stability of a slender beam extruded in a highly viscous fluid. Piano wires were extruded axially at constant speed in a tank filled with corn syrup. The force necessary to extrude the wire was measured to increase linearly at first until the compressive viscous force causes the wire to buckle. A numerical model, coupling a lengthening elastica formulation with resistive-force theory, predicts a similar behavior. The model is used to study the dynamics at large time when the beam is highly deformed. It is found that at large time, a large deformation regime exists in which the force necessary to extrude the beam at constant speed becomes constant and length independent. With a proper dimensional analysis, the beam can be shown to buckle at a critical length based on the extrusion speed, the bending rigidity, and the dynamic viscosity of the fluid. Hypothesizing that the trichocysts of Paramecia must be sized to maximize their thrust per unit volume as well as avoid buckling instabilities, we predict that their bending rigidity must be about 3 ×10-9N μ m2 . The verification of this prediction is left for future work.

  12. Studies on positive conveying in helically channeled single screw extruders

    Directory of Open Access Journals (Sweden)

    L. Pan

    2012-07-01

    Full Text Available A solids conveying theory called double-flight driving theory was proposed for helically channeled single screw extruders. In the extruder, screw channel rotates against static barrel channel, which behaves as cooperative embedded twin-screws for the positive conveying. They turn as two parallel arc plates, between which an arc-plate solid-plug was assumed. By analyzing the forces on the solid-plug in the barrel channel and screw channel, the boundary conditions when the solid-plug is waived of being cut off on barrel wall, were found to have the capacity of the positive conveying. Experimental data were obtained using a specially designed extruder with a helically channeled barrel in the feeding zone and a pressure-adjustable die. The effects of the barrel channel geometry and friction coefficients on the conveying mechanism were presented and compared with the experimental results. The simulations showed that the positive conveying could be achieved after optimizing extruder designs. Compared with the traditional design with the friction-drag conveying, the throughput is higher while screw torque and energy consumption are decreased. Besides, the design criteria of the barrel channel were also discussed.

  13. 99. 99% Al/ 6063 Alloy Co-extruded beam chamber

    Energy Technology Data Exchange (ETDEWEB)

    Ishimaru, H.; Narushima, K.; Kanazawa, K.

    1988-09-30

    In an electron storage ring, synchrotron radiation causes stimulated gas desorption from the vacuum chamber wall. It raises the operating pressure far above the ultrahigh vacuum range needed for long beam lifetimes. In order to determine an ideal material for low dynamic gas desorption we have studied the properties of co-extruded 99.99%Al/ 6063 alloy. (AIP)

  14. The influence of plasticizer on extruded thermoplastic starch

    NARCIS (Netherlands)

    VanderBurgt, M.C.; VanderWoude, M.E.; Janssen, L.P.B.M.; Burgt, M.C. van der; Woude, M.E. van der

    1996-01-01

    This paper describes the use of an extruder for the plastification process of potato starch with glycerol and water as plasticizers. The influence of both plasticizers is expressed in the water absorption index (WAI) and water solubility index (WSI). The amount of water added prior to extrusion is a

  15. The study on stress-cone based on HTS cable terminal

    Science.gov (United States)

    Wu, C. Y.; Fang, J.; Huang, X. H.; Lu, W. J.; Li, D.; Guo, L. J.

    2013-01-01

    Our research aims at improving the performance of 35 kV class stress-cone for HTS cable terminal. Firstly, the equivalent circuit model of a stress-cone is constructed for simulation. The relation between the sag voltage of each layer can be characterized by structural and material parameters, such as the stress-cone’s plate length, plate radius, insulating material thickness and dielectric constant. Secondly, the simulation based on ANSYS is developed for analyzing the electric field of stress cone of HTS cable terminal, by altering the length of step and insulation material parameter of stress cone, we get the voltage of each plate layer, horizontal electric field and vertical electric field, and the influence of stress-cone parameter on stress cone electric field is analyzed.

  16. Umbilical Cable Recovery Load Analysis

    Institute of Scientific and Technical Information of China (English)

    YAN Shu-wang; JIA Zhao-lin; FENG Xiao-wei; LI Shi-tao

    2013-01-01

    Umbilical cable is a kind of integrated subsea cable widely used in the exploration and exploitation of oil and gas field.The severe ocean environment makes great challenges to umbilical maintenance and repair work.Damaged umbilical is usually recovered for the regular operation of the offshore production system.Analysis on cables in essence is a two-point boundary problem.The tension load at the mudline must be known first,and then the recovery load and recovery angle on the vessel can be solved by use of catenary equation.The recovery analysis also involves umbilicalsoil interaction and becomes more complicated.Calculation methods for recovery load of the exposed and buried umbilical are established and the relationship between the position of touch down point and the recovery load as well as the recovery angle and recovery load are analyzed.The analysis results provide a theoretical reference for offshore on-deck operation.

  17. Umbilical cable recovery load analysis

    Science.gov (United States)

    Yan, Shu-wang; Jia, Zhao-lin; Feng, Xiao-wei; Li, Shi-tao

    2013-06-01

    Umbilical cable is a kind of integrated subsea cable widely used in the exploration and exploitation of oil and gas field. The severe ocean environment makes great challenges to umbilical maintenance and repair work. Damaged umbilical is usually recovered for the regular operation of the offshore production system. Analysis on cables in essence is a two-point boundary problem. The tension load at the mudline must be known first, and then the recovery load and recovery angle on the vessel can be solved by use of catenary equation. The recovery analysis also involves umbilical-soil interaction and becomes more complicated. Calculation methods for recovery load of the exposed and buried umbilical are established and the relationship between the position of touch down point and the recovery load as well as the recovery angle and recovery load are analyzed. The analysis results provide a theoretical reference for offshore on-deck operation.

  18. Cable Television: From Here to Where?

    Science.gov (United States)

    Canadian Cable Television Association, Ottawa (Ontario).

    A brief description is presented of the present uses, regulatory structure, and future potentials of cable television for Canada. Some 30% of Canada is already wired for cable, as opposed to 9% in the United States. (RH)

  19. Magnetization Losses of Roebel Cable Samples with 2G YBCO Coated Conductor Strands

    CERN Document Server

    Yang, Y.; Falorio, I.; Young, E.A.; Kario, A.; Goldacker, W.; Dhallé, M. M. J.; van Nugteren, J.; Kirby, G.; Bottura, L.; Ballarino, A.

    2016-01-01

    Roebel cable with 2G YBCO strands is one of the promising HTS solutions of fully transposed high current conductors for high field accelerator magnets. Following the considerable research effort on the manufacturing of Roebel cables in recent years, sample conductors are now available in useful lengths with reproducible performances to allow detailed characterizations beyond the standard critical current measurements. The ac loss and strands coupling are of significant interest for the field quality of the accelerator magnets. We report a set of systematic ac loss measurements on two different Roebel cable samples prepared for the EuCARD2 collaboration. The measurements were performed over a wide range of temperature between 5 K and 90 K and the results were analyzed in the context of strands architecture and coupling. The results show that the transposed bundles are partially decoupled and the strands in transposition sections behave as an isolated single tape if the strands are insulated.

  20. 47 CFR 76.640 - Support for unidirectional digital cable products on digital cable systems.

    Science.gov (United States)

    2010-10-01

    ... products on digital cable systems. 76.640 Section 76.640 Telecommunication FEDERAL COMMUNICATIONS... Standards § 76.640 Support for unidirectional digital cable products on digital cable systems. (a) The requirements of this section shall apply to digital cable systems. For purposes of this section, digital...

  1. External electromagnetic transient sources: analysis of its effect in underground power cables; Fuentes transitorias electromagneticas externas: analisis de su efecto en los cables de potencia subterraneos

    Energy Technology Data Exchange (ETDEWEB)

    Escamilla Paz, Antonio

    2009-07-01

    In most of the electrical power systems that operate at present, the subterranean cables are only a complement. The cost of these cables is generally higher than the one of the aerial power lines, thus its use is restricted only to those areas where the construction of the aerial power lines is not feasible. It is estimated that for voltages lower than 110 kV this cost is up to seven times greater than the one of an aerial power line and for voltages higher than 380 kV it can be up to twenty times greater. Nevertheless, important reasons exist to construct a subterranean cable system such as: a) the fast growth of the urban centers and the industrial zones, which brings about restrictions of the rights of way for the construction of aerial power lines, b) the crossing of large water bodies, c) the congestion of aerial power lines near the generating substations or power plants, d) the crossing of air lines and e) the laws and the regulations, to mention some of them. The importance of the underground transmission systems of high and extra high voltage will be increased in the medium and the long term, therefore, it is considered that the effects of the external phenomena in these systems, like the inductions produced by the electromagnetic transient sources, will be more severe. In this research work the atmospheric discharges are defined as the external electromagnetic transient sources. The large dimension cables such as the power cables, behave as large collectors of the interferences produced by the atmospheric discharges, which can bring about damages in the components of a system. In order to avoid the damages and to increase the reliability of the subterranean cable systems it is necessary to use protective devices and appropriate insulation levels, mainly. If the phenomenon and the behavior of the system are properly represented, it is possible to more accurately determine the characteristics that the equipment must have to resist the over voltages and the

  2. Online Cable Tester and Rerouter

    Science.gov (United States)

    Lewis, Mark; Medelius, Pedro

    2012-01-01

    Hardware and algorithms have been developed to transfer electrical power and data connectivity safely, efficiently, and automatically from an identified damaged/defective wire in a cable to an alternate wire path. The combination of online cable testing capabilities, along with intelligent signal rerouting algorithms, allows the user to overcome the inherent difficulty of maintaining system integrity and configuration control, while autonomously rerouting signals and functions without introducing new failure modes. The incorporation of this capability will increase the reliability of systems by ensuring system availability during operations.

  3. IntelliCable Interface Specification

    Science.gov (United States)

    2016-07-14

    manager on how to use this. Some will factor the priority into account and always consume the highest priority while others...Battlefield Air Operations power manager uses a 10 pin Glenair Mighty Mouse connector with default keying . Pin 9 is specified as the IntelliCable pin. A BAO...standard Soldier Power Manager uses a 7 pin Glenair Mighty Mouse Connector, using alternative keying distinct from the Land Warrior battery specification, and the Li-145 battery. Pin 3 is defined as the IntelliCable pin.

  4. Motility of Electric Cable Bacteria

    OpenAIRE

    Bjerg, Jesper Tataru; Damgaard, Lars Riis; Holm, Simon Agner; Schramm, Andreas; Nielsen, Lars Peter

    2016-01-01

    Cable bacteria are filamentous bacteria that electrically couple sulfide oxidation and oxygen reduction at centimeter distances, and observations in sediment environments have suggested that they are motile. By time-lapse microscopy, we found that cable bacteria used gliding motility on surfaces with a highly variable speed of 0.5 ± 0.3 μm s−1 (mean ± standard deviation) and time between reversals of 155 ± 108 s. They frequently moved forward in loops, and formation of twisted loops revealed ...

  5. Processing and characterization of extruded zein-based biodegradable films

    Science.gov (United States)

    Wang, Ying

    The objectives of this study were to prepare biodegradable zein films by extrusion processing and to evaluate relevant physical properties of resulting films with respect to their potential as packaging materials. The manufacture of protein-based packaging films by extrusion has remained a challenge. In this study, a zein resin was prepared by combining zein and oleic acid. This resin was formed into films by blown extrusion at the bench-top scale. Resin moisture content and extruder barrel temperature profile were identified as major parameters controlling the process. The optimum temperature of the blowing head was determined to be 40--45°C, while optimum moisture at film collection was 14--15%. Physico-chemical properties of the extruded products were characterized. Extruded products exhibited plastic behavior and ductility. Morphology characterization by SEM showed micro voids in extruded zein sheets, caused by entrapped air bubbles or water droplets. DSC characterization showed that zein was effectively plasticized by oleic acid as evidenced by the lowered glass transition temperature of zein films. X-ray scattering was used to investigate changes in zein molecular aggregation during processing. It was observed that higher mechanical energy treatment progressively disrupted zein molecular aggregates, resulting in a more uniform distribution of individual zein molecules. With the incorporation of oleic acid as plasticizer and monoglycerides as emulsifier, zein formed structures with long-range periodicity which varied depending on the formulation and processing methods. Processing methods for film formation affected the binding of oleic acid to zein with higher mechanical energy treatment resulting in better interaction between the two components. The moisture sorption capacity of extruded zein films was reduced due to the compact morphology caused by extrusion. Plasticization with oleic acid further reduced moisture sorption of zein films. The overall

  6. Special insulator for installation of optical phase conductor on 15 kV line

    Energy Technology Data Exchange (ETDEWEB)

    Argasinska, H. [Energoprojekt-Warszawa, Warsaw (Poland); Fleszynski, J.; Sojda, E.; Tyman, A. [Wroclaw Univ. (Poland)

    1997-12-31

    The use of optical fibres for the transmission of information over high-voltage lines was discussed. Three designs of fibre optic cables that can be run on HV lines: (1) optical ground wire (OPGW) cables run within ground wires, (2) all dielectric self-supporting (ADSS) cables suspended from overhead transmission line, and (3) Fibwrap (Skywrap) cables wrapped around the ground wire and which, in some cases, run on the phase conductors. To date, the market has been dominated by OPGW. Transmission of information by fibre optic cable requires a special insulator-separator. Tests were conducted on insulator-separators made of polycarbonate, silicon rubber-thermosetting, silicon rubber-RTV and polymer concrete to check their compliance with the high voltage requirements for pollution zone 3. Not all the materials met the requirements for this zone. A Polish-made insulator made of silicon rubber RTV and which met the requirements for pollution zone 3, was installed on a 15 kV power line. 5 refs., 1 tab., 4 figs.

  7. Superconducting cables: Long distance energy transmission. (Latest citations from the NTIS bibliographic database). Published Search

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-06-01

    The bibliography contains citations concerning the design, development, and evaluation of superconducting cables and power transmission lines for long distance energy transmission. Topics include methods of cryogenic refrigeration and electrical insulation, fabrication and development of niobium alloy conductors, energy loss analysis, and dielectric design of superconducting power transmission systems. Government research reports on superconducting technology for electric power transmission and distribution are also reviewed.(Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  8. Low smoke, non-corrosive, fire retardant cable jackets based on HNBR and EVM

    Energy Technology Data Exchange (ETDEWEB)

    Meisenheimer, H.

    1991-06-01

    This article examines the properties of the polymers HNBR and EVM which make them good candidates for use in meeting the low smoke, non-corrosive, low toxicity and fire retardant requirements for electric safety cable jackets and electric insulation. Topics of the article include density, weight, and viscosity of each polymer, mechanical proprieties of each polymer, and other results of laboratory testing of these polymers.

  9. North American Submarine Cable Association (NASCA) Submarine Cables

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data show the locations of in-service and out-of-service submarine cables that are owned by members of NASCA and located in U.S. territorial waters. More...

  10. Remote Acquisition Amplifier For 50-Ohm Cable

    Science.gov (United States)

    Amador, Jose J.

    1995-01-01

    Buffer-amplifier unit designed to drive 50-Ohm cables up to 100 ft. (30 m) long, compensating for attenuation in cables and enabling remote operation of oscilloscopes. Variable resistor provides for adjustment of gain of amplifier, such that overall gain from input terminals of amplifier to output end of cable set to unity.

  11. Aspen Notebook: Cable and Continuing Education.

    Science.gov (United States)

    Adler, Richard; Baer, Walter S.

    This is the first of a planned series of Aspen Notebooks on cable television (CATV). Part I reports on research conducted by the Aspen Workshop on Uses of the Cable. It describes the status of continuing education and the history of educational television and explores the prospects created by cable's development for extending access to continuing…

  12. 47 CFR 32.2422 - Underground cable.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Underground cable. 32.2422 Section 32.2422... FOR TELECOMMUNICATIONS COMPANIES Instructions for Balance Sheet Accounts § 32.2422 Underground cable. (a) This account shall include the original cost of underground cable installed in conduit and of...

  13. Cable Television Report and Suggested Ordinance.

    Science.gov (United States)

    League of California Cities, Sacramento.

    Guidelines and suggested ordinances for cable television regulation by local governments are comprehensively discussed in this report. The emphasis is placed on franchising the cable operator. Seventeen legal aspects of franchising are reviewed, and an exemplary ordinance is presented. In addition, current statistics about cable franchising in…

  14. Strain relief for power-cable connectors

    Science.gov (United States)

    Dean, W. T., III

    1980-01-01

    Easily fabricated grommet composed of polytetrafluoroethylene cylinder, containing U-shaped channels equally spaced around periphery, is used in power cable connectors to relieve strain on cables. Utilization of grommets provides more ease in cable insertion and removal. Potential applications include wiring in large residential and commercial buildings.

  15. Reducing Magnetic Fields Around Power Cables

    Science.gov (United States)

    Sargent, Noel B.; Gitelman, Florida; Pongracz-Bartha, Edward; Spalding, John

    1993-01-01

    Four power conductors arranged symmetrically about fifth grounded conductor. Four current-carrying wires arranged symmetrically around central grounded wire that nominally carries no current. In comparison with other cable configurations, this one results in smaller magnetic fields around cable. Technique for use when size of wires in cable makes twisting impractical.

  16. 30 CFR 18.45 - Cable reels.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Cable reels. 18.45 Section 18.45 Mineral... § 18.45 Cable reels. (a) A self-propelled machine, that receives electrical energy through a portable cable and is designed to travel at speeds exceeding 2.5 miles per hour, shall have a...

  17. 47 CFR 32.2421 - Aerial cable.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Aerial cable. 32.2421 Section 32.2421... FOR TELECOMMUNICATIONS COMPANIES Instructions for Balance Sheet Accounts § 32.2421 Aerial cable. (a) This account shall include the original cost of aerial cable and of drop and block wires served by...

  18. 47 CFR 32.2423 - Buried cable.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Buried cable. 32.2423 Section 32.2423... FOR TELECOMMUNICATIONS COMPANIES Instructions for Balance Sheet Accounts § 32.2423 Buried cable. (a) This account shall include the original cost of buried cable as well as the cost of other material...

  19. Submerged Medium Voltage Cable Systems at Nuclear Power Plants. A Review of Research Efforts Relevant to Aging Mechanisms and Condition Monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Brown, Jason [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Bernstein, Robert [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); White, II, Gregory Von [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Glover, Steven F. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Neely, Jason C. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Pena, Gary [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Williamson, Kenneth Martin [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Zutavern, Fred J. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Gelbard, Fred [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-03-01

    In a submerged environment, power cables may experience accelerated insulation degradation due to water - related aging mechanisms . Direct contact with water or moisture intrusion in the cable insulation s ystem has been identified in the literature as a significant aging stressor that can affect performance and lifetime of electric cables . Progressive reduction of the dielectric strength is commonly a result of water treeing which involves the development of permanent hydrophilic structures in the insulation coinciding with the absorption of water into the cable . Water treeing is a phenomenon in which dendritic microvoids are formed in electric cable insulation due to electrochemic al reactions , electromechanical forces , and diffusion of contaminants over time . These reactions are caused by the combined effect s of water presence and high electrical stress es in the material . Water tree growth follow s a tree - like branching pattern , i ncreasing in volume and length over time . Although these cables can be "dried out," water tree degradation , specifically the growth of hydrophilic regions, is believed to be permanent and typically worsens over time. Based on established research , water treeing or water induced damage can occur in a variety of electric cables including XLPE, TR - XLPE and other insulating materials, such as EPR and butyl rubber . Once water trees or water induced damage form, the dielectric strength of an insulation materia l will decrease gradually with time as the water trees grow in length, which could eventually result in failure of the insulating material . Under wet conditions or i n submerged environments , several environmental and operational parameters can influence w ater tree initiation and affect water tree growth . These parameters include voltage cycling, field frequency, temperature, ion concentration and chemistry, type of insula tion material , and the characteristics of its defects. In this effort, a review of academic

  20. Influence of metallic trays on the ac resistance and ampacity of low-voltage cables under non-sinusoidal currents

    Energy Technology Data Exchange (ETDEWEB)

    Demoulias, Charis; Labridis, Dimitris P.; Dokopoulos, Petros; Gouramanis, Kostas [Aristotle University of Thessaloniki, Department of Electrical and Computer Engineering, Thessaloniki (Greece)

    2008-05-15

    This paper investigates the influence of metallic trays on the ac resistance of PVC insulated, low-voltage (0.6/1.0 kV) cables made according to CENELEC standard HD603. The investigation is made with a validated finite element model for the fundamental and higher harmonic frequencies. It is shown that the cable's effective resistance is affected significantly by the relative magnetic permeability and specific conductivity of the tray, while the tray's dimensions do not affect it. The orientation of the cable with respect to the tray also influences the ac resistance of the phase and neutral conductors. An ampacity derating factor is defined and calculated for various cable cross-sections and harmonic loads. The presence of a metallic tray is shown to cause an additional derating of cable's ampacity which is relatively significant at large cable cross-sections. Working examples demonstrate the application of the results in calculating the ampacity of low-voltage cables and in assessing the energy savings that will result from the use of active harmonic filters. (author)

  1. Influence Factors Analysis of Interface Pressure in High Voltage Cable Accessories%高压电缆附件界面压力的影响因素分析

    Institute of Scientific and Technical Information of China (English)

    柳松; 彭嘉康; 王霞; 王陈诚; 崔浩

    2013-01-01

    The interface pressure between cable accessory and cable insulation is the key to ensure the safety of cable accessory. Based on the interface pressure which determined the discharge characteristics of cable accessory, several influence factors of interface pressure were introduced, that is the roughness between cable accessory and cable insulation, temperature and the stress relaxation characteristics of cable accessory material. The long-term operational reliability of cable accessory can increase by increasing the interface smoothness, controlling the operation temperature rise of cable and selecting the accessory materi-al with relaxation resistance.%电缆附件和电缆绝缘间的界面压力是确保电缆附件安全运行的关键。基于决定电缆附件界面放电特性的界面压力,介绍了影响电缆附件界面压力的几个主要因素:电缆附件和电缆绝缘界面的粗糙度、温度和电缆附件材料的应力松驰特性。得出增加界面光滑度、控制电缆运行温升、选择耐松驰性附件材料等措施可提高电缆附件的长期运行可靠性。

  2. Power applications for superconducting cables

    DEFF Research Database (Denmark)

    Tønnesen, Ole; Hansen, Steen; Jørgensen, Preben

    2000-01-01

    High temperature superconducting (HTS) cables for use in electric ac power systems are under development around the world today. There are two main constructions under development: the room temperature dielectric design and the cryogenic dielectric design. However, theoretical studies have shown...

  3. Educational Uses of Cable Television.

    Science.gov (United States)

    Cable Television Information Center, Washington, DC.

    The different educational uses of cable television as well as the methods and problems of that use are described in a state of the art review. The Federal Communications Commission regulations and related franchise activity are described, and the methods of using the educational channel as open or closed circuit TV or pay TV are indicated for…

  4. Cable Television: Developing Community Services.

    Science.gov (United States)

    Carpenter-Huffman, Polly; And Others

    The final volume of a four-volume study focuses on community use of cable television systems. Four separate aspects are discussed extensively: the possibilities of public access, use in municipal service applications, uses in education, and a guide for education planners. Each section contains several appendixes and the education sections include…

  5. Improving Energy Efficiency Cable Production

    Directory of Open Access Journals (Sweden)

    Iashutina Olga

    2016-01-01

    Full Text Available During the energy calculation is made at different temperatures of the heating surface. The influence of the speed of pulling on the cost of the finished products of cable products. The interrelation of speed broaching and temperature of the heating surface.

  6. temperature distribution in underground cable system

    Directory of Open Access Journals (Sweden)

    Rerak Monika

    2017-01-01

    Full Text Available The paper presents a mathematical model of heat transfer in the underground cable system. The computations were performed for flat formation of power cables buried in the ground at a depth of 2 meters. The model allows determining the two-dimensional temperature distribution in the soil, thermal backfill and power cables. The simulations studied the effect of soil thermal conductivity on the maximum temperature of the cable conductor. Furthermore, the effect of thermal backfill soil conductivity on the cable conductor temperature was studied. Numerical analyses were performed based on a program written in MATLAB.

  7. Offshore Cable Installation - Lillgrund. Lillgrund Pilot Project

    Energy Technology Data Exchange (ETDEWEB)

    Unosson, Oscar (Vattenfall Vindkraft AB, Stockholm (Sweden))

    2009-01-15

    This report describes the installation method and the experiences gained during the installation of the submarine cables for the offshore wind farm at Lillgrund. The wind farm consists of 48 wind turbines and is expected to produce 0.33 TWh annually. Different aspects of the installation, such as techniques, co-operation between the installation teams, weather conditions and regulatory and environmental issues are described in this report. In addition, recommendations and guidelines are provided, which hopefully can be utilised in future offshore wind projects. The trenches, in which the submarine cables were laid, were excavated weeks before the cable laying. This installation technique proved to be successful for the laying of the inter array cables. The export cable, however, was laid into position with difficulty. The main reason why the laying of the export cable proved more challenging was due to practical difficulties connected with the barge entrusted with the cable laying, Nautilus Maxi. The barge ran aground a number of times and it had difficulties with the thrusters, which made it impossible to manoeuvre. When laying the inter array cables, the method specification was closely followed, and the laying of the cables was executed successfully. The knowledge and experience gained from the offshore cable installation in Lillgrund is essential when writing technical specifications for new wind plant projects. It is recommended to avoid offshore cable installation work in winter seasons. That will lower the chances of dealing with bad weather and, in turn, will reduce the risks

  8. Cable Harness Assembly Planning in Virtual Environment

    Institute of Scientific and Technical Information of China (English)

    LIU Jianhua; NING Ruxin; BAI Shuqing; WANG Bile

    2006-01-01

    Based on the analysis of characteristic of cable harness planning in virtual environment, a discrete control node modeling (DCNM) method of cable harness in virtual environment and the cable harness assembly routing technique based on it are proposed. DCNM converts a cable harness into continuous flexed line segments connected by a series of section center points, and the design can realize cable harness planning through controlling those control nodes. This method of cable harness routing in the virtual environment breaks the status that virtual assembly process planning is just suitable for the rigid components at present, and impulse the virtual assembly process planning to be more practical. Relation algorithms have been verified in a self-developed system named virtual cable harness assembly planning (VCHAP) system, and this VCHAP system has been applied in assembly process planning of aerospace-related products.

  9. Power applications for superconducting cables in Denmark

    DEFF Research Database (Denmark)

    Tønnesen, Ole; Østergaard, Jacob; Olsen, S. Krüger

    1999-01-01

    In Denmark a growing concern for environmental protection has lead to wishes that the open country is kept free of overhead lines as far as possible. New lines under 100 kV and existing 60/50 kV lines should be established as underground cables. Superconducting cables represent an interesting...... alternative to conventional cables, as they are able to transmit two or more times the energy than a conventional cable. HTS cables with a room temperature dielectric design are especially interesting as a target for replacing overhead lines. Superconducting cables in the overall network are of interest...... in cases such as transmission of energy into cities and through areas of special interest. The planned large groups of windmills in Denmark generating up to 2000 MVA or more both on dry land and off-shore will be an obvious case for the application of superconducting AC or DC cables. These opportunities...

  10. Self-healing cable apparatus and methods

    Science.gov (United States)

    Huston, Dryver (Inventor); Esser, Brian (Inventor)

    2007-01-01

    Self-healing cable apparatus and methods are disclosed. The cable has a central core surrounded by an adaptive cover that can extend over the entire length of the cable or just one or more portions of the cable. The adaptive cover includes a protective layer having an initial damage resistance, and a reactive layer. When the cable is subjected to a localized damaging force, the reactive layer responds by creating a corresponding localized self-healed region. The self-healed region provides the cable with enhanced damage resistance as compared to the cable's initial damage resistance. Embodiments of the invention utilize conventional epoxies or foaming materials in the reactive layer that are released to form the self-healed region when the damaging force reaches the reactive layer.

  11. Gjoea power cable; a green solution

    Energy Technology Data Exchange (ETDEWEB)

    Dretvik, Svein-Egil

    2010-07-01

    An alternative to today's power generation offshore using either gas or diesel, is alternating current (AC) electric power cable from shore. The power from shore through the AC cable gives high savings for the environment. The cable replaces 4 gas turbines with a total CO2 disposal of 240 00 tonnes each year which represents the disposal of 100 000 cars. ABB was awarded the contract which includes engineering, fabrication and installation of the power cable from Mongstad to the Gjoea platform which will be the longest AC cable in the world with a total length of 100 km. The presentation will include system design, qualification of dynamic power cable, cable fabrication experiences, testing at fabrication yard and installation aspects. (Author)

  12. High Voltage Testing of a 5-meter Prototype Triaxial HTS Cable

    Energy Technology Data Exchange (ETDEWEB)

    Sauers, Isidor [ORNL; James, David Randy [ORNL; Ellis, Alvin R [ORNL; Tuncer, Enis [ORNL; Pace, Marshall O [ORNL; Gouge, Michael J [ORNL; Demko, Jonathan A [ORNL; Lindsay, David T [ORNL

    2007-01-01

    High voltage tests were performed on a 5-m long prototype triaxial HTS cable (supplied by Ultera) at ORNL in preparation for installation of a 200-m HTS cable of the same design at the AEP utility substation in Columbus, Ohio. The triaxial design comprises three concentric phases and shield around a common former with the phase to phase dielectric at cryogenic temperature. Advantages of this design include increased current density, a reduced amount of HTS tape needed, and reduced heat load. The phase to phase voltage will be 13.2 kVrms (7.6 kVrms to ground). Preliminary testing was done on half-scale and full-scale terminations which successfully passed AC withstand, partial discharge, and impulse tests. High voltage tests conducted on the 5-m cable with the cable straight and after bending 90 degrees were ac withstand to 39 kVrms, partial discharge inception, and a minimum of 10 positive and 10 negative lightning waveform impulses at 110 kV. Phase to phase insulation was tested by applying high voltage to each phase one at a time with all the other phases grounded. Partial discharge data will be presented. The 5-m prototype triaxial HTS cable passed all the HV tests performed, with a PD inception voltage significantly above the required voltage.

  13. DC Insulation Parameter Characteristics of XLPE in the Course of Its Aging

    Institute of Scientific and Technical Information of China (English)

    WANG Hong-xin; CHENG Shu-kang; WEN Xi-shan; YAO Hong-yu; CHEN Yun-ping

    2005-01-01

    This paper deals with the experimental study on the correlation between insulation resistance (R) and direct current (DC) component (idc) and corresponding aging degree of insulation in the course of the aging within cross linked polyethylene (XLPE)insulation. The aging tests were performed on a section of 10 kV transmission XLPE cable by means of water needle method, and R was measured by DC voltage superimposed method. R and idc were found to be significantly dependent on the corresponding aging degree of insulation in the course of aging of XLPE, and different kind of aging stage has different characteristics. Beside, there are generally similar regularity but different amplitude in the course of aging of XLPE insulation in different electrolyte, and the various electrochemical tree were found on the surface of aging XLPE cable immersed in CuSO4 solution. Therefore, according to the changing regularity of the DC characteristic parameters i.e. R and idc within XLPE insulation judging the aging degree of XLPE insulation will be an effective method.

  14. Strongly Correlated Topological Insulators

    Science.gov (United States)

    2016-02-03

    Research Triangle Park , NC 27709-2211 Condensed Matter, Topological Phases of Matter REPORT DOCUMENTATION PAGE 11. SPONSOR/MONITOR’S REPORT NUMBER(S...Strongly Correlated Topological Insulators In the past year, the grant was used for work in the field of topological phases, with emphasis on finding...surface of topological insulators. In the past 3 years, we have started a new direction, that of fractional topological insulators. These are materials

  15. Evaluation of roll-extruded Alloy 718 tubing

    Energy Technology Data Exchange (ETDEWEB)

    Smolik, G R; Korth, G E

    1978-05-01

    A sample of roll-extruded Alloy 718 tubing, a product identified for use in the Clinch River Breeder Reactor, was evaluated. The tubing satisfied AMS 5589 requirements for seamless tubing, and had tensile and fatigue properties comparable to plate for the conventional 955/sup 0/C (1750/sup 0/F) heat treatment. Recrystallization was retarded in this product and bands of very small grains resulted from the conventional heat treatment. Both as-roll-extruded and directly aged material showed the results of thermomechanical processing in high strengths and reductions in area. It is recommended that work continue toward realizing improved fatigue and stress rupture properties in this product by means of ''Minigrain'' and thermomechanical processing. 10 figures, 6 tables.

  16. A Novel cooked extruded lentils analog: physical and chemical properties.

    Science.gov (United States)

    Abu-Ghoush, Mahmoud; Alavi, Sajid; Al-Shathri, Abdulaziz

    2015-07-01

    Developing an extruded lentil analog is our aim. Lentil analog with six formulations were produced using a pilot-scale single (SS) and twin screw (TS) extruders. Texture analysis of lentil analogs prepared for consumption revealed that the products formulated with 60:40 and 70:30 soy: wheat ratios exhibited a significantly higher hardness, adhesiveness and lower springiness as compared to all other treatments. Differential Scanning Calorimeter (DSC) results indicated that all starches in dry blend are completely 100 % gelatinized by extrusion for all treatments at 100 °C. The maximum peak of viscosity for TS was formed after 5.58 min. from the run at 89.9 °C for the best treatment. However, this lentil analog product can provide a high quality lentil which can be used as a substitute for regular lentils.

  17. OPLC成缆质量的控制%Cabling Quality Control of OPLC

    Institute of Scientific and Technical Information of China (English)

    金金元

    2012-01-01

    As an important type of cable products in intelligent power grid, optical fiber composite low voltage cable (OPLC) is a product that has the highest cost-effectiveness in "multi-networks integration" intelligent cable products at present. Since OPLC contains insulated conductor and optical fiber unit, the control of cabling die is different from that of ordinary low voltage cables. Consequently, the control of OPLC cabling quality (including the choosing of filling materials, the choosing of cabling die, the control of core tension, the tautness control of wrapping, and the choosing of taking-up drum) is described in detail.%光纤复合低压电缆(OPLC)作为智能电网建设中的重要线缆产品之一,是目前性价比最高的“多网融合”智能电缆产品。由于OPLC结构中包含了绝缘线芯和光单元,因此其成缆质量的控制与普通低压电缆成缆有许多不同。从填充材料的选用、成缆模具的选用、线芯张力的控制、绕包的松紧及收线盘的选择等几个方面对OPLC成缆质量(包括外观圆整度和光单元传输性能等)控制的影响进行了详细的阐述。

  18. Composite Flexible Blanket Insulation

    Science.gov (United States)

    Kourtides, Demetrius A. (Inventor); Pitts, William C. (Inventor); Goldstein, Howard E. (Inventor); Sawko, Paul M. (Inventor)

    1991-01-01

    Composite flexible multilayer insulation systems (MLI) were evaluated for thermal performance and compared with the currently used fibrous silica (baseline) insulation system. The systems described are multilayer insulations consisting of alternating layers of metal foil and scrim ceramic cloth or vacuum metallized polymeric films quilted together using ceramic thread. A silicon carbide thread for use in the quilting and the method of making it are also described. These systems are useful in providing lightweight insulation for a variety of uses, particularly on the surface of aerospace vehicles subject to very high temperatures during flight.

  19. Plasmonics in Topological Insulators

    Directory of Open Access Journals (Sweden)

    Yi-Ping Lai

    2014-04-01

    Full Text Available With strong spin-orbit coupling, topological insulators have an insulating bulk state, characterized by a band gap, and a conducting surface state, characterized by a Dirac cone. Plasmons in topological insulators show high frequency-tunability in the mid-infrared and terahertz spectral regions with transverse spin oscillations, also called “spin-plasmons”. This paper presents a discussion and review of the developments in this field from the fundamental theory of plasmons in bulk, thin-film, and surface-magnetized topological insulators to the techniques of plasmon excitation and future applications.

  20. Early-age volume changes of extrudable reactive powder concrete

    Directory of Open Access Journals (Sweden)

    De Noirfontaine M.N.

    2010-06-01

    Full Text Available This article presents a study on the early-age autogenous deformations of Extrudable Reactive Powder Concretes (ERPCs, especially designed for the making of concrete pipes by extrusion. Different ERPC mixtures, with variable amounts of polycarboxylate superplasticizer (SP, have been investigated. Results on 28-day mechanical properties, early-age hydration rate, autogenous shrinkage and premature cracking risk are analyzed and discussed in relation with the ERPC mix parameters.

  1. Early-age volume changes of extrudable reactive powder concrete

    Science.gov (United States)

    Cherkaoui, K.; Courtial, M.; Dunstetter, F.; Khelidj, A.; Mounanga, P.; de Noirfontaine, M. N.

    2010-06-01

    This article presents a study on the early-age autogenous deformations of Extrudable Reactive Powder Concretes (ERPCs), especially designed for the making of concrete pipes by extrusion. Different ERPC mixtures, with variable amounts of polycarboxylate superplasticizer (SP), have been investigated. Results on 28-day mechanical properties, early-age hydration rate, autogenous shrinkage and premature cracking risk are analyzed and discussed in relation with the ERPC mix parameters.

  2. Early-age volume changes of extrudable reactive powder concrete

    OpenAIRE

    De Noirfontaine M.N.; Mounanga P.; Khelidj A.; Dunstetter F.; Cherkaoui K.; Courtial M.

    2010-01-01

    This article presents a study on the early-age autogenous deformations of Extrudable Reactive Powder Concretes (ERPCs), especially designed for the making of concrete pipes by extrusion. Different ERPC mixtures, with variable amounts of polycarboxylate superplasticizer (SP), have been investigated. Results on 28-day mechanical properties, early-age hydration rate, autogenous shrinkage and premature cracking risk are analyzed and discussed in relation with the ERPC mix parameters.

  3. Essential fatty acids in extruded and raw dog foods

    OpenAIRE

    Karlsen, Juni S.

    2015-01-01

    This thesis is divided into two sections: section 1 explaining the theory about fat and fatty acids functions, health effects and sources, section 2 includes a study of commercial extruded and raw dog foods. Fat is the most energy dens nutrient and functions as energy, structural components in cell membranes, source of essential fatty acids (EFA), precursor to biological active substrates and carrier of fat-soluble vitamins. EFA cannot be synthesized by the animal, and needs to be added ...

  4. Enrichment of extruded snack products with whey protein

    OpenAIRE

    Mladen Brnčić; Sven Karlović; Tomislav Bosiljkov; Branko Tripalo; Damir Ježek; Ivana Cugelj; Valentina Obradović

    2008-01-01

    Highest share in products with whey proteins addition belongs to aromatised drinks, aromatised protein bars and various dietetic preparations. In the last few years, there is increased use of the extrusion process for production of food products. This process is, besides other things, used for obtaining directly expanded products, which are immediately packed and sent on market after mechanical and thermal treatment in extruder, or after drying for a short time. One of these food products is ...

  5. Benchmark Accelerated Aging of Harvested Hypalon/Epr and Cspe/Xlpe Power and I&C Cable in Nuclear Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Duckworth, Robert C.; Frame, Emily; Fifield, Leonard S.; Glass, Samuel W.

    2016-08-30

    As part of the Light Water Reactor and Sustainability (LWRS) program in the U.S. Department of Energy (DOE) Office of Nuclear Energy, material aging and degradation research is currently geared to support the long-term operation of existing nuclear power plants (NPPs) as they move beyond their initial 40 year licenses. The goal of this research is to provide information so that NPPs can develop aging management programs (AMPs) to address replacement and monitoring needs as they look to operate for 20 years, and in some cases 40 years, beyond their initial operating lifetimes. For cable insulation and jacket materials that support instrument, control, and safety systems, accelerated aging data are needed to determine priorities in cable aging management programs. Before accelerated thermal and radiation aging of harvested, representative cable insulation and jacket materials, the benchmark performance of a new test capability at Oak Ridge National Laboratory (ORNL) was evaluated for temperatures between 70 and 135°C, dose rates between 100 and 500 Gy/h, and accumulated doses up to 20 kGy, Samples that were characterized and are representative of current materials in use were harvested from the Callaway NPP near Fulton, Missouri, and the San Onofre NPP north of San Diego, California. From the Callaway NPP, a multiconductor control rod cable manufactured by Boston Insulated Wire (BIW), with a Hypalon/ chorolosulfonated polyethylene (CSPE) jacket and ethylene-propylene rubber (EPR) insulation, was harvested from the auxiliary space during a planned outage in 2013. This cable was placed into service when the plant was started in 1984. From the San Onofre NPP, a Rockbestos Firewall III (FRIII) cable with a Hypalon/ CSPE jacket with cross-linked polyethylene (XLPE) insulation was harvested from an on-site, climate-controlled storage area. This conductor, which was never placed into service, was procured around 2007 in anticipation of future operation that did not occur

  6. BENCHMARK ACCELERATED AGING OF HARVESTED HYPALON/EPR AND CSPE/XLPE POWER AND I&C CABLE IN NUCLEAR POWER PLANTS

    Energy Technology Data Exchange (ETDEWEB)

    Duckworth, Robert C [ORNL; Fifield, Dr Leonard S [Pacific Northwest National Laboratory (PNNL)

    2016-01-01

    As part of the Light Water Reactor and Sustainability (LWRS) program in the U.S. Department of Energy (DOE) Office of Nuclear Energy, material aging and degradation research is currently geared to support the long-term operation of existing nuclear power plants (NPPs) as they move beyond their initial 40 year licenses. The goal of this research is to provide information so that NPPs can develop aging management programs (AMPs) to address replacement and monitoring needs as they look to operate for 20 years, and in some cases 40 years, beyond their initial operating lifetimes. For cable insulation and jacket materials that support instrument, control, and safety systems, accelerated aging data are needed to determine priorities in cable aging management programs. Before accelerated thermal and radiation aging of harvested, representative cable insulation and jacket materials, the benchmark performance of a new test capability at Oak Ridge National Laboratory (ORNL) was evaluated for temperatures between 70 and 135 C, dose rates between 100 and 500 Gy/h, and accumulated doses up to 20 kGy, Samples that were characterized and are representative of current materials in use were harvested from the Callaway NPP near Fulton, Missouri, and the San Onofre NPP north of San Diego, California. From the Callaway NPP, a multiconductor control rod cable manufactured by Boston Insulated Wire (BIW), with a Hypalon/ chorolosulfonated polyethylene (CSPE) jacket and ethylene-propylene rubber (EPR) insulation, was harvested from the auxiliary space during a planned outage in 2013. This cable was placed into service when the plant was started in 1984. From the San Onofre NPP, a Rockbestos Firewall III (FRIII) cable with a Hypalon/ CSPE jacket with cross-linked polyethylene (XLPE) insulation was harvested from an on-site, climate-controlled storage area. This conductor, which was never placed into service, was procured around 2007 in anticipation of future operation that did not occur

  7. Extrudability and Consolidation of Blends between CGM and DDGS

    Directory of Open Access Journals (Sweden)

    C. J. R. Verbeek

    2016-01-01

    Full Text Available During the last decade, the global biofuels industry has experienced exponential growth. By-products such as high protein corn gluten meal (CGM and high fibre distillers dried grains with solubles (DDGS have grown in parallel. CGM has been shown to be suitable as a biopolymer; the high fibre content of DDGS reduces its effectiveness, although it is considerably cheaper. In this study, the processing behaviour of CGM and DDGS blends was evaluated and resulting extrudate properties were determined. Prior to processing, urea was used as a denaturant. DDGS : CGM ratios of 0, 33, 50, 66, and 100% were processed in a single screw extruder, which solely used dissipative heating. Blends containing DDGS were less uniformly consolidated and resulted in more dissipative heating. Blends showed multiple glass transitions, which is characteristic of mechanically compatible blends. Transmission electron microscopy revealed phase separation on a microscale, although distinct CGM or DDGS phases could not be identified. On a macroscale, optical microscopy suggested that CGM-rich blends were better consolidated, supported by visual observations of a more continuous extrudate formed during extrusion. Future work should aim to also characterize the mechanical properties of these blends to assess their suitability as either bioplastic feedstock or pelletized livestock feed.

  8. Enrichment of extruded snack products with whey protein

    Directory of Open Access Journals (Sweden)

    Mladen Brnčić

    2008-08-01

    Full Text Available Highest share in products with whey proteins addition belongs to aromatised drinks, aromatised protein bars and various dietetic preparations. In the last few years, there is increased use of the extrusion process for production of food products. This process is, besides other things, used for obtaining directly expanded products, which are immediately packed and sent on market after mechanical and thermal treatment in extruder, or after drying for a short time. One of these food products is “snack” food. Snack food is made with twin corotating screw extruders, in which raw materials are submitted to high temperatures and short time, with intensive expansion and rapid pressure drop. For the production of this category of food products, basic ingredients like corn, wheat, rye and rice, with the maximum of 9 % of proteins, are used. With the development of extrusion technology, special attention is focused on the enrichment of extruded products with different types of proteins, including proteins. In this paper, review of the newest research and achievements in embedding various types of whey concentrates in snack food will be represented. This category of food products for direct consummation is constantly increasing, and addition of whey protein concentrate adds better nutritional value and increased functionality.

  9. Comparative Analysis of Thermography Studies and Electrical Measurement of Partial Discharges in Underground Power Cables

    Science.gov (United States)

    Gonzalez-Parada, A.; Guzman-Cabrera, R.; Torres-Cisneros, M.; Guzman-Sepulveda, J. R.

    2015-09-01

    The principal cause of damage in underground power cable installations is partial discharge (PD) activity. PD is a localized non-linear phenomenon of electrical breakdown that occurs in the insulating medium sitting between two conducting materials, which are at different potentials. The damage to the insulating material is induced by the AC voltage to which the insulator is subjected during the discharge process, and it can be directly or indirectly measured by the charge displacement across the insulation and the cavity defect. Non-invasive detection techniques that help in identifying the onset of the discharge process are required as PD is a major issue in terms of maintenance and performance of underground power installations. The main locations of failure are the accessories at points of connection such as terminals or splices. In this article, a study of electrical detection of PD and image processing of thermal pictures is presented. The study was carried out by controllably inducing specific failures in the accessories of the installation. The temporal evolution of the PD signals was supported with thermal images taken during the test in order to compare the PD activity and thermal increase due to failure. The analysis of thermographic images allows location of the failure by means of intensity-based texture segmentation algorithms. This novel technique was found to be suitable for non-invasive detection of the PD activity in underground power cable accessories.

  10. Nonlinear Analysis of Cable Vibration of a Multispan Cable-Stayed Bridge under Transverse Excitation

    OpenAIRE

    Kun Lin; Dujian Zou; Minghai Wei

    2014-01-01

    The nonlinear vibrations of cable in a multispan cable-stayed bridge subjected to transverse excitation are investigated. The MECS (multielements cable system) model, where multielements per cable stay are used, is built up and used to analyze the model properties of the multispan cable-stayed bridges. Then, a simplified two-degrees-of-freedom (2-DOFs) model, where the tower or the deck is reduced to a beam, is proposed to analyze the nonlinear dynamic behaviors of the beam and cable. The res...

  11. Design of load-to-failure tests of high-voltage insulation breaks for ITER's cryogenic network

    CERN Document Server

    Langeslag, S A E; Aviles Santillana, I; Sgobba, S; Foussat, A

    2015-01-01

    The development of new generation superconducting magnets for fusion research, such as the ITER experiment, is largely based on coils wound with so-called cable-in-conduit conductors. The concept of the cable-in-conduit conductor is based on a direct cooling principle, by supercritical helium, flowing through the central region of the conductor, in close contact with the superconducting strands. Consequently, a direct connection exists between the electrically grounded helium coolant supply line and the highly energised magnet windings. Various insulated regions, constructed out of high-voltage insulation breaks, are put in place to isolate sectors with different electrical potential. In addition to high voltages and significant internal helium pressure, the insulation breaks will experience various mechanical forces resulting from differential thermal contraction phenomena and electro-magnetic loads. Special test equipment was designed, prepared and employed to assess the mechanical reliability of the insul...

  12. MIC-Large Scale Magnetically Inflated Cable Structures for Space Power, Propulsion, Communications and Observational Applications

    Science.gov (United States)

    Powell, James; Maise, George; Rather, John

    2010-01-01

    A new approach for the erection of rigid large scale structures in space-MIC (Magnetically Inflated Cable)-is described. MIC structures are launched as a compact payload of superconducting cables and attached tethers. After reaching orbit, the superconducting cables are energized with electrical current. The magnet force interactions between the cables cause them to expand outwards into the final large structure. Various structural shapes and applications are described. The MIC structure can be a simple flat disc with a superconducting outer ring that supports a tether network holding a solar cell array, or it can form a curved mirror surface that concentrates light and focuses it on a smaller region-for example, a high flux solar array that generates electric power, a high temperature receiver that heats H2 propellant for high Isp propulsion, and a giant primary reflector for a telescope for astronomy and Earth surveillance. Linear dipole and quadrupole MIC structures are also possible. The linear quadrupole structure can be used for magnetic shielding against cosmic radiation for astronauts, for example. MIC could use lightweight YBCO superconducting HTS (High Temperature Superconductor) cables, that can operate with liquid N2 coolant at engineering current densities of ~105 amp/cm2. A 1 kilometer length of MIC cable would weigh only 3 metric tons, including superconductor, thermal insulations, coolant circuits, and refrigerator, and fit within a 3 cubic meter compact package for launch. Four potential MIC applications are described: Solar-thermal propulsion using H2 propellant, space based solar power generation for beaming power to Earth, a large space telescope, and solar electric generation for a manned lunar base. The first 3 applications use large MIC solar concentrating mirrors, while the 4th application uses a surface based array of solar cells on a magnetically levitated MIC structure to follow the sun. MIC space based mirrors can be very large and light

  13. Condition Monitoring of Power Cables

    OpenAIRE

    Lewin, P L; L. Hao; Swaffield, D J; Swingler, S.G.

    2007-01-01

    A National Grid funded research project at Southampton has investigated possible methodologies for data acquisition, transmission and processing that will facilitate on-line continuous monitoring of partial discharges in high voltage polymeric cable systems. A method that only uses passive components at the measuring points has been developed and is outlined in this paper. More recent work, funded through the EPSRC Supergen V, UK Energy Infrastructure (AMPerES) grant in collaboration with UK ...

  14. Cable aging and condition monitoring of radiation resistant nano-dielectrics in advanced reactor applications

    Energy Technology Data Exchange (ETDEWEB)

    Duckworth, Robert C [ORNL; Aytug, Tolga [ORNL; Paranthaman, Mariappan Parans [ORNL; Kidder, Michelle [ORNL; Polyzos, Georgios [ORNL; Leonard, Keith J [ORNL

    2015-01-01

    Cross-linked polyethylene (XLPE) nanocomposites have been developed in an effort to improve cable insulation lifetime to serve in both instrument cables and auxiliary power systems in advanced reactor applications as well as to provide an alternative for new or retro-fit cable insulation installations. Nano-dielectrics composed of different weight percentages of MgO & SiO2 have been subjected to radiation at accumulated doses approaching 20 MRad and thermal aging temperatures exceeding 100 C. Depending on the composition, the performance of the nanodielectric insulation was influenced, both positively and negatively, when quantified with respect to its electrical and mechanical properties. For virgin unradiated or thermally aged samples, XLPE nanocomposites with 1wt.% SiO2 showed improvement in breakdown strength and reduction in its dissipation factor when compared to pure undoped XLPE, while XLPE 3wt.% SiO2 resulted in lower breakdown strength. When aged in air at 120 C, retention of electrical breakdown strength and dissipation factor was observed for XLPE 3wt.% MgO nanocomposites. Irrespective of the nanoparticle species, XLPE nanocomposites that were gamma irradiated up to the accumulated dose of 18 MRad showed a significant drop in breakdown strength especially for particle concentrations greater than 3 wt.%. Additional attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy measurements suggest changes in the structure of the XLPE SiO2 nanocomposites associated with the interaction of silicon and oxygen. Discussion on the relevance of property changes with respect to cable aging and condition monitoring is presented.

  15. Translucent insulating building envelope

    DEFF Research Database (Denmark)

    Rahbek, Jens Eg

    1997-01-01

    A new type of translucent insulating material has been tested. This material is made of Celulose-Acetat and have a honey-comb structure. The material has a high solar transmittance and is highly insulating. The material is relatively cheap to produce. Danish Title: Translucent isolerende klimaskærm....

  16. Translucent insulating building envelope

    DEFF Research Database (Denmark)

    Rahbek, Jens Eg

    1997-01-01

    A new type of translucent insulating material has been tested. This material is made of Celulose-Acetat and have a honey-comb structure. The material has a high solar transmittance and is highly insulating. The material is relatively cheap to produce. Danish Title: Translucent isolerende klimaskærm....

  17. Low Friction Cryostat for HTS Power Cable of Dutch Project

    NARCIS (Netherlands)

    Chevtchenko, O.; Zuijderduin, R.; Smit, J.; Willen, D.; Lentge, H.; Thidemann, C.; Traeholt, C.

    2012-01-01

    Particulars of 6 km long HTS AC power cable for Amsterdam project are: a cable has to fit in an annulus of 160 mm, with only two cooling stations at the cable ends [1]. Application of existing solutions for HTS cables would result in excessively high coolant pressure drop in the cable, possibly affe

  18. Broadband description of the copper cable transfer function

    NARCIS (Netherlands)

    Waal, D.C.H.

    2007-01-01

    This report is describes the characteristics of two different copper cables, namely the coax cable and the twisted pair cable. By using the Maxwell equations we can describe the coax cable and the twisted pair cable with the Bessel functions. By these Bessel functions we can simulate the two seconda

  19. 30 CFR 75.603 - Temporary splice of trailing cable.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Temporary splice of trailing cable. 75.603... SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Trailing Cables § 75.603 Temporary splice of trailing cable. One temporary splice may be made in any trailing cable. Such trailing cable...

  20. Sound Insulation between Dwellings

    DEFF Research Database (Denmark)

    Rasmussen, Birgit

    2011-01-01

    Regulatory sound insulation requirements for dwellings exist in more than 30 countries in Europe. In some countries, requirements have existed since the 1950s. Findings from comparative studies show that sound insulation descriptors and requirements represent a high degree of diversity...... and initiate – where needed – improvement of sound insulation of new and existing dwellings in Europe to the benefit of the inhabitants and the society. A European COST Action TU0901 "Integrating and Harmonizing Sound Insulation Aspects in Sustainable Urban Housing Constructions", has been established and runs...... 2009-2013. The main objectives of TU0901 are to prepare proposals for harmonized sound insulation descriptors and for a European sound classification scheme with a number of quality classes for dwellings. Findings from the studies provide input for the discussions in COST TU0901. Data collected from 24...