Condition based maintenance of a 20 kV-PE/XLPE-insulated cable network using the IRC-Analysis; Zustandsorientierte Instandhaltung eines polymerisolierten 20-kV-Kabelnetzes mit der IRC-Analyse. Moderne Diagnostik reduziert Stoerungsrate

Energy Technology Data Exchange (ETDEWEB)

Hoff, G.; Kranz, H.G. [BUGH Wuppertal (Germany). Labs. fuer Hochspannungstechnik; Beigert, M.; Petzold, F. [Seba Dynatronic Mess- und Ortungstechnik GmbH, Baunach (Germany); Kneissl, C. [Bereich Konzeption und Messtechnik, Lech Elektrizitaetswerke AG, Augsburg (Germany)

2001-10-22

For a preventive maintenance of a polymer insulated cable network a destruction free estimation of the status of the buried PE/XLPE-cables is needed. This contribution presents a condition based maintenance concept which is based on the IRC-Analysis. With this concept a major German utility was able to reduce the amount of failures in a part of the 20kV-cable network. The general tendency of increasing faults was broken. (orig.) [German] Die praeventive Instandhaltung in polymerisolierten Kabelnetzen setzt eine zerstoerungsfreie Zustandbestimmung von gelegten PE/VPE-isolierten Kabeln voraus. Die-Verfasser beschreiben ein zustandsorientiertes Wartungskonzept auf Basis der IRC-Analyse, mit dem es gelungen ist, in einem Teil des 20-kV-Kabelnetzes eines Energieversorgers die in der Vergangenheit stetig steigende Stoerungsrate drastisch zu reduzieren. (orig.)

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.)

Cable aging tests

International Nuclear Information System (INIS)

Hubbard, G.

1993-01-01

This paper describes the results from aging, condition monitoring, and loss-of-coolant accident (LOCA) testing of class 1E electrical cables, per NUREG/CR-5772. This test was designed to test the performance of cables which had been aged with simultaneous radiation and thermal exposure. The tested cables included crosslinked polyolefin cables, ethylene propylene rubber cables, and miscellaneous cable types. Cables were exposed to 20, 40, and 60 years equivalent aging, and then exposed to LOCA tests at the end of their qualified life to determine the minimum insulation thickness needed for survival of the test. Failures were found in a large number of the tested cables. As a result the NRC has sent information notices to the industry regarding potential insulation problems. The results have raised the question of whether the artificial aging methods provide adequate testing methods. As a result of this testing the NRC is reviewing the artificial aging procedures, the adequacy of environmental qualification requirements for cable safety, and reexamining data from condition monitoring of installed cables

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

Science.gov (United States)

2012-04-02

... resistant cables shall have strip tension of 0 through 18 pounds (0 through 8.16 kg). Comment: General Cable suggested changing the requirement of stripping tension for TR-XLPE cable to the industry standard of a maximum of 24 lb. Limiting the maximum stripping tension to 18 lb will cause quality cable to be rejected...

Estimation of Medium Voltage Cable Parameters for PD Detection

DEFF Research Database (Denmark)

Villefrance, Rasmus; Holbøll, Joachim T.; Henriksen, Mogens

1998-01-01

Medium voltage cable characteristics have been determined with respect to the parameters having influence on the evaluation of results from PD-measurements on paper/oil and XLPE-cables. In particular, parameters essential for discharge quantification and location were measured. In order to relate...... and phase constants. A method to estimate this propagation constant, based on high frequency measurements, will be presented and will be applied to different cable types under different conditions. The influence of temperature and test voltage was investigated. The relevance of the results for cable...

Double Layered Sheath in Accurate HV XLPE Cable Modeling

DEFF Research Database (Denmark)

Gudmundsdottir, Unnur Stella; Silva, J. De; Bak, Claus Leth

2010-01-01

This paper discusses modelling of high voltage AC underground cables. For long cables, when crossbonding points are present, not only the coaxial mode of propagation is excited during transient phenomena, but also the intersheath mode. This causes inaccurate simulation results for high frequency...

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

International Nuclear Information System (INIS)

Markey, L; Stevens, G C

2003-01-01

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

Cable indenter aging monitor

International Nuclear Information System (INIS)

Shook, T.A.; Gardner, J.B.

1988-07-01

This project was undertaken to develop a hand-held, nondestructive test device to assess the aged condition of electrical cable by in situ measurement of mechanical properties of polymeric jackets and insulations. The device is an indenter similar to those used to make hardness measurements. Comparison of measurements made on installed cables with previous measurements serving as baseline aging/mechanical property data will determine the state of aging of the field cables. Such a device will be valuable in nuclear and fossil plant life extension programs. Preliminary laboratory tests on cables covered with ethylene propylene rubber (EPR) and chlorosulfated polyethylene (CSPE) point to the measurement of the rate of force increase resulting from constant rate deformation as having the best correlation with progressive thermal aging. This first phase of the work has demonstrated the technical feasibility of the method. A second phase will include the generation of additional groundwork data and the design of the portable indenter for in situ plant measurements

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

Ship nuclear power device of cable aging management

International Nuclear Information System (INIS)

Wei Hua; Chen Miao; Chen Tao

2012-01-01

Cable for marine nuclear power plant continuous delivery of electrical energy. Cable is mostly in the high temperature and strong radiation and harsh working environment, and can not be replaced in the lifetime This should be the cable aging management methods through research, maintenance and repair program to provide a scientific basis. Cable aging management approach for a number of different levels of cable management at different levels, relying on computers and other modern tools, the use of information management database software maintenance of the cable through the science of aging control. Cable Aging Management including the scope of cable aging management, classification management basis and used for different levels of management supervision and implementation of means testing approach. Application of the ship that has the operational management science, both planned maintenance to improve the science, but also improves the efficiency of aging management. This management method can be extended to nuclear power plants of cable aging management. (authors)

Modelling of long High Voltage AC Cables in the Transmission System

DEFF Research Database (Denmark)

Gudmundsdottir, Unnur Stella

: conductor-insulation (with or without SC layers)-conductor-insulation(-conductor-insulation), whereas a transmission line single core XLPE cable will normally have the configuration: conductor-SC layerinsulation-SC layer-conductor-SC layer-conductor-insulation. Furthermore the existing cable models use......, 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......-SC layer-solid hollow conductor) is implemented in the model. These improvements result in a more correct series impedance and hence a more correct damping of the simulations. Even though the series impedance is more correct, it does still not include the proximity effect and high frequency oscillations...

NEPO cable system aging management programs

International Nuclear Information System (INIS)

Toman, G.

2002-01-01

Full text: Cable polymer aging and condition monitoring is being studied in detail under the Nuclear Energy Plant Optimization Program (NEPO) that is co-sponsored by the U.S. Department of Energy and EPRI. Significant advances in modeling of polymer aging and condition monitoring have occurred and continue to be developed. The activities include: Analysis of the linearity of the Arrhenius model to room temperature; Development of a wear-out technique for determining remaining life of cable polymers; Determination of the aging fragility point for composite EPR/CSPE insulation with respect to LOCA function; Development of visual/tactile training aids for cable assessment; Development of a totally new nuclear magnetic resonance condition monitoring technique; Assessment of existing techniques with regard to repeatability, accuracy and ease of use. Through use of highly precise oxygen consumption experiments, the linearity of the Arrhenius model is being evaluated. In these experiments, polymer is placed in vials with a known amount of oxygen and aged at much lower temperatures than is possible with standard accelerated aging techniques. aging results are possible at room temperature. The technique is being applied to commonly used insulation and jacket polymers. The wear-out technique allows highly non-linear aging behavior to be made linear. The wearout point of a polymer is determined through high-rate aging and use of a condition monitoring technique to establish the end point. Then, micro-samples of cable that have been naturally aged are subjected to high rate aging to the same end point. The ratio of the remaining high rate aging period to the total high rate aging time provides a linear indication of the remaining service time. Initial screening of nuclear plant cable systems can use visual/tactile techniques to identify cable that has aged significantly. Training aids have been developed by developing sets of specimens with accelerated aging ranging from none

Development of evaluation technique on ageing degradation of organic polymer in nuclear power plant

Energy Technology Data Exchange (ETDEWEB)

Kim, Ki Yup; Nho, Young Chang; Jung, Sung Hee; Park, Eun Hee

1999-03-01

Radiation degradation of chlorosulfonated polyethylene (CSPE, Hypalon), crosslinked polyethylene (XLPE), poly (tetrafluoroethylene) (PTFE), poly (vinylidene fluoride) (PVDF), and ethylene rubber (EPR) of experimental formulation as cable insulating and sheathing materials were performed by accelerated ageing tests and was investigated by measuring the properties such as tensile strength, elongation, insulation resistance, melting temperature, oxygen index and thermal stimulated current. The status of radiation ageing test was reviewed and the requirement of qualification of nuclear equipment was documented.

Development of evaluation technique on ageing degradation of organic polymer in nuclear power plant

International Nuclear Information System (INIS)

Kim, Ki Yup; Nho, Young Chang; Jung, Sung Hee; Park, Eun Hee

1999-03-01

Radiation degradation of chlorosulfonated polyethylene (CSPE, Hypalon), crosslinked polyethylene (XLPE), poly (tetrafluoroethylene) (PTFE), poly (vinylidene fluoride) (PVDF), and ethylene rubber (EPR) of experimental formulation as cable insulating and sheathing materials were performed by accelerated ageing tests and was investigated by measuring the properties such as tensile strength, elongation, insulation resistance, melting temperature, oxygen index and thermal stimulated current. The status of radiation ageing test was reviewed and the requirement of qualification of nuclear equipment was documented

Online Location of Faults on AC Cables in Underground Transmission Systems

DEFF Research Database (Denmark)

Jensen, Christian Flytkjær

under fault conditions well, but the accuracy of the calculated impedance is low for fault location purposes. The neural networks can therefore not be trained and no impedance-based fault location method can be used for crossbonded cables or hybrid lines. The use of travelling wave-based methods...... connection to verify the proposed method. Faults, at reduced a voltage are artificially applied in the cable system and the transient response is measured at two terminals at the cable’s ends. The measurements are time-synchronised and it is found that a very accurate estimation of the fault location can......A transmission grid is normally laid out as an almost pure overhead line (OHL) network. The introduction of transmission voltage level XLPE cables and the increasing interest in the environmental impact of OHL has resulted in an increasing interest in the use of underground cables on transmission...

Ageing of instrumentation and control cables in NPPs

International Nuclear Information System (INIS)

Santhosh; Ghosh, A.K.; Fernandes, B.G.

2011-01-01

Cables are vital components of instrumentation and control (I and C) systems in nuclear power plants (NPPs). The polymer materials used for insulation and jacket materials for electric cables are susceptible to ageing and degradation mechanisms caused by exposure to many of the stressors encountered in NPP service conditions. Ageing of components in NPP is an important concern since the degradation caused by ageing can impact the performance of susceptible equipment. This is of particular concern for safety-related equipment since the failure due to ageing can compromise the continued safe operation of the plant. The state-of-the art for incorporating cable ageing effects into probabilistic safety assessment (PSA) is still evolving and in the reliability assessment of NPP systems, the ageing effect of electrical cable is generally not considered and also, there is no standard method exists for incorporating such ageing effects into the system reliability. Therefore, identification and quantification of ageing of electrical cables is very much essential for an accurate prediction of system reliability for PSA applications. The objective of this study is to develop a methodology to assess the susceptibility of polymeric cable insulation to various ageing mechanisms; and the state of the insulation at any chosen time in order to evaluate the remaining life-time of operating cables in NPPs. This paper presents the state-of-the-art tools and techniques for insulation condition assessment, insulation life prediction methodologies, equipment qualification guidelines, and ageing management programs relating to I and C cables in NPPs. An approach to calculate the insulation resistance subjecting to different stressors has also been presented in this paper. (author)

Danida1

DEFF Research Database (Denmark)

Henriksen, Mogens

1996-01-01

At the request of Danish Ministry of Foreign Affairs, Department TSA.4, electrical testing of possibly damaged cables has been evaluated. This matter concerns three different types of cable, which are10 km 30(36) kV XLPE armoured submarine power cable, 1-phase15 km 30(36) kV XLPE armoured...

Danida3

DEFF Research Database (Denmark)

Henriksen, Mogens

1996-01-01

At the request of Danish Ministry of Foreign Affairs, Department TSA.4, electrical testing of possibly damaged cables has been evaluated. This matter concerns three different types of cable, which are,10 km 30(36) kV XLPE armoured submarine power cable, 1-phase15 km 30(36) kV XLPE armoured...

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

Interim report on assessment of cable aging for nuclear power plants

International Nuclear Information System (INIS)

2006-12-01

Research on assessment of cable aging for nuclear power plants (NPPs) started in 2002 in order to obtain data of safety-related cables affected by thermal aging, simultaneous thermal and radiation aging, and Loss-of-Coolant Accident (LOCA) equivalent test, which could contribute to draft guideline on comprehensive assessment of cable aging for NPPs while taking into consideration the latest knowledge. For the cable aging test, cross-linked polyethylene, flame-retardant cross-linked polyethylene, ethylene propylene rubber, flame-retardant ethylene propylene rubber, silicone rubber and special heat-resistant polyvinyl chloride insulators were selected from the safety-related cables used in the nuclear power plants. Furthermore, 2 to 3 kinds of cables with insulators of different manufacturers were added making a total of 14 kinds of cable specimens for the test. Aging period was selected as a basic parameter while three temperature conditions for thermal aging specimen and combined nine conditions of three temperatures with three dose rates for simultaneous aging specimens. Degradation of cable aging was characterized by elongation at break of tensile test. LOCA test for 9 kinds of cables was also conducted using the simultaneous aging specimens. Furthermore, the investigation of applicability of non-destructive degradation diagnostic technologies for aged cables was conducted to confirm the validity of cable aging evaluation at actual operating plants. Interim report was issued in 2006 and based on cable aging test until 21,000 hrs maximum; 1) a significant difference might be observed at times in the aging progress depending on the insulator manufacturer even if the insulator type was identical, 2) activation energy values calculated from the thermal aging test data were smaller than those currently used and principles of calculation and application of the activation energy were developed for evaluation and 3) superposition of time dependent data was applicable to

Crystal River 3 Cable Materials for Thermal and Gamma Radiation Aging

Energy Technology Data Exchange (ETDEWEB)

Fifield, Leonard S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Correa, Miguel [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Zwoster, Andy [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2017-09-07

The Expanded Materials Degradation Assessment Volume 5: Aging of Cables and Cable Systems (EMDA) summarizes the state of knowledge of materials, constructions, operating environments, and aging behavior of low voltage and medium cables in nuclear power plants (NPPs) and identifies potential knowledge gaps with regard to cable operation beyond 60 years. The greatest area of uncertainty relates to how well the accelerated aging used in the original equipment qualification (EQ) processes predicts the performance of cable materials in extended operation. General opinion and utility experience have indicated that actual operating environments of in-plant cables are not as severe, however, as the operating and design basis environments used in the qualification process. Better understanding of the long term aging behavior of cable insulation materials in service conditions and the analysis of actual cable operating environments are the objectives of ongoing research to support subsequent license renewal activities in particular and long term cable aging management in general. A key component of the effort to better understand cable material aging behavior is the availability of representative samples of cables that have been installed in operating light water reactors and have experienced long term service. Unique access to long term service cables, including relatively rich information on cable identity and history, occurred in 2016 through the assistance of the Electric Power Research Institute (EPRI). EPRI facilitated DOE receipt of harvested cables from the decommissioned Crystal River Unit 3 (CR3) pressurized water reactor representing six of the nine most common low voltage cable manufacturers (EPRI 103841R1): Rockbestos, Anaconda Wire and Cable Company (Anaconda), Boston Insulated Wire (BIW), Brand-Rex, Kerite and Okonite. Cable samples received had been installed in the operating plant for durations ranging from 10 years to 36 years. These cables provide the

Evaluation of cable aging degradation based on plant operating condition

International Nuclear Information System (INIS)

Kim, Jong-Seog

2005-01-01

Extending the lifetime of nuclear power plant [(hereafter referred simply as ''NPP'')] is one of the most important concerns in the world nuclear industry. Cables are one of the long live items which have not been considered to be replaced during the design life of NPP. To extend the cable life beyond the design life, we need to prove that the design life is too conservative compared with the actual aging. Condition monitoring is one of the useful ways for evaluating the aging condition of cable. In order to simulate the natural aging in nuclear power plant, a study on accelerated aging needs to be conducted first. In this paper, evaluations of mechanical aging degradation for cable jacket were performed after accelerated aging under the continuous heating and intermittent heating. Contrary to general expectation, the intermittent heating to cable jacket showed low aging degradation, 50% break-elongation and 60% indenter modulus, compared with continuous heating. With the plant maintenance period of 1 month after every 12 or 18 months operation, we can easily deduce that the life time of cable jacket can be extended much longer than estimated through the general EQ (Environmental Qualification) test, which adopts continuous accelerated aging for determining cable life. Therefore, a systematic approach which considers the actual environment condition of nuclear power plant is required for determining the life of cables. (author)

New trends in design and fabrication of signal and power cables to increase nuclear safety

International Nuclear Information System (INIS)

Salmen, Florin; Florescu, Gheorghe; Ionescu, Aurel

2007-01-01

Based on NPP operating experiences in the past, it was found that the inadequate management of aging degradation caused shortening of the lifetime of equipment, which in turn, hindered plant life extension. Aging degradation of plant structures and components should be properly managed to ensure the designated safety function of plant systems during design life and extended life. From a safety perspective, aging management means maintaining the aging degradation level in major equipment and structures below the allowable limit and holding the capacity to sustain abnormal operating condition. Cable aging was not considered as a significant factor in relation to the nuclear power plant maintenance due to its long life which is almost the same as the plant design life. Attempts to extend the lifetime of NPP has become one of the major concern in the nuclear industry world wide. Consequently, life evaluation and lifetime management of cables to survive over 40 years has become major topic of discussion. In connection to this, accelerated aging must be studied in detail in order to simulate the natural aging in NPP. Test results for evaluating aging degradation after accelerated aging of polyethylene jacket will be described herein.There are hundred types of cables in NPPs. These cables can be classified as medium/low voltage cable, low power cable, instrument and control cable, panel connect line cable, special cable, security line cable, phone line cable and ground cable. Insulation and jacket material in electrical cables are fabricated of polymer materials combined with a number of additives and filler to provide the required mechanical, electrical and fire retardant proprieties. The most commonly used insulation materials are XLPE/EPR/EPDM and PVC. PVC has been widely used as an insulation material, particularly in old plants, but it is less used in modern plants. Neoprene/CSPE/PVC are commonly used material for nuclear cable jacket. The old types of cables

Frequency Domain Reflectometry NDE for Aging Cables in Nuclear Power Plants

Energy Technology Data Exchange (ETDEWEB)

Glass, Samuel W.; Jones, Anthony M.; Fifield, Leonard S.; Hartman, Trenton S.

2017-02-16

Cable insulation polymers are among the more susceptible materials to age-related degradation within a nuclear power plant. This is recognized by both regulators and utilities, so all plants have developed cable aging management programs to detect damage before critical component failure in compliance with regulatory guidelines. Although a wide range of tools are available to evaluate cables and cable systems, cable aging management programs vary in how condition monitoring and nondestructive examinations are conducted as utilities search for the most reliable and cost-effective ways to assess cable system condition. Frequency domain reflectometry (FDR) is emerging as one valuable tool to locate and assess damaged portions of a cable system with minimal cost and only requires access in most cases to one of the cable terminal ends. Since laboratory studies to evaluate the use of FDR for inspection of aged cables can be expensive and data interpretation may be confounded by multiple factors which influence results, a model-based approach is desired to parametrically investigate the effect of insulation material damage in a controlled manner. This work describes development of a physics-based FDR model which uses finite element simulations of cable segments in conjunction with cascaded circuit element simulations to efficiently study a cable system. One or more segments of the cable system model have altered physical or electrical properties which represent the degree of damage and the location of the damage in the system. This circuit model is then subjected to a simulated FDR examination. The modeling approach is verified using several experimental cases and by comparing it to a commercial simulator suitable for simulation of some cable configurations. The model is used to examine a broad range of parameters including defect length, defect profile, degree of degradation, number and location of defects, FDR bandwidth, and addition of impedance-matched extensions to

Behaviour at thermal ageing of power cable components through penetrations

International Nuclear Information System (INIS)

Puiu, D.; Gyongyosi, T.; Dinu, E.

2009-01-01

The materials for electric insulation and exterior jackets of the power cables are formulated organic compounds. The environmental service conditions will induce chemical and/or physical processes at molecular level of the material; these processes are the ageing mechanisms. The power cables passing through penetrations lead to an increase of the rate of thermal ageing mechanisms, resulting in irreversible degradation of mechanical and electric properties of the organic compounds and of the functional properties of the cable. The paper presents the results of the laboratory tests when the real environmental service conditions for penetration are simulated, the comparison with the results of the thermal computation of the power cables heating and the evaluation of the influence of temperature increase of the power cable components on the cable lifetime. For the particular case of a power cable with PVC insulation, we estimated a lifetime decrease about seven years as referred to lifetime of about 30 years for operation in air. (authors)

Aging, Loss-of-Coolant Accident (LOCA), and high potential testing of damaged cables

International Nuclear Information System (INIS)

Vigil, R.A.; Jacobus, M.J.

1994-04-01

Experiments were conducted to assess the effects of high potential testing of cables and to assess the survivability of aged and damaged cables under Loss-of-Coolant Accident (LOCA) conditions. High potential testing at 240 Vdc/mil on undamaged cables suggested that no damage was incurred on the selected virgin cables. During aging and LOCA testing, Okonite ethylene propylene rubber (EPR) cables with a bonded jacket experienced unexpected failures. The failures appear to be primarily related to the level of thermal aging and the presence of a bonded jacket that ages more rapidly than the insulation. For Brand Rex crosslinked polyolefin (XLPO) cables, the results suggest that 7 mils of insulation remaining should give the cables a high probability of surviving accident exposure following aging. The voltage necessary to detect when 7 mils of insulation remain on unaged Brand Rex cables is approximately 35 kVdc. This voltage level would almost certainly be unacceptable to a utility for use as a damage assessment tool. However, additional tests indicated that a 35 kvdc voltage application would not damage virgin Brand Rex cables when tested in water. Although two damaged Rockbestos silicone rubber cables also failed during the accident test, no correlation between failures and level of damage was apparent

Assessment and management of ageing of electrical instrumentation and control cables

Energy Technology Data Exchange (ETDEWEB)

Pachner, J. [International Atomic Energy Agency IAEA, Vienna (Austria); Burnay, S.G. [John Knott Associates Ltd., Newbury (United Kingdom)

2001-07-01

This paper presents a summary of the results of an IAEA Co-ordinated Research Project (CRP) on Management of Ageing of In-containment Instrumentation and Control (I and C) Cables addressing current practices and techniques for assessing and managing ageing degradation of cables in real nuclear power plant (NPP) environments. These practices and techniques include environmental qualification, identification of cables of concern, condition monitoring, and predictive modelling. The paper shows how they should be integrated within a plant-specific ageing management programme utilising a systematic ageing management process, which is an adaptation of Deming Plan-Do-Check-Act cycle to ageing management. (author)

Assessment and management of ageing of electrical instrumentation and control cables

International Nuclear Information System (INIS)

Pachner, J.; Burnay, S.G.

2001-01-01

This paper presents a summary of the results of an IAEA Co-ordinated Research Project (CRP) on Management of Ageing of In-containment Instrumentation and Control (I and C) Cables addressing current practices and techniques for assessing and managing ageing degradation of cables in real nuclear power plant (NPP) environments. These practices and techniques include environmental qualification, identification of cables of concern, condition monitoring, and predictive modelling. The paper shows how they should be integrated within a plant-specific ageing management programme utilising a systematic ageing management process, which is an adaptation of Deming Plan-Do-Check-Act cycle to ageing management. (author)

Light Water Reactor Sustainability Program: Evaluation of Localized Cable Test 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); Fifield, Leonard S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hartman, Trenton S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2016-05-30

This Pacific Northwest National Laboratory (PNNL) milestone report describes progress to date on the investigation of nondestructive test (NDE) methods focusing particularly on local measurements 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 NPPs consider applying for second, or subsequent, license renewal (SLR) to extend their operating period from 60 years to 80 years, it important to understand how the materials installed in plant systems and components will age during that time and develop aging management programs (AMPs) 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 is directed toward the more demanding challenge of assuring the cable function under accident or DBE. Most utilities already have a program associated with their first life extension from 40 to 60 years. Regrettably, there is neither a clear guideline nor a single NDE that can assure cable function and integrity for all cables. Thankfully, however, practical implementation of a broad range of tests allows utilities to develop a practical program that assures cable function to a high degree. 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 is a destructive test so the test programs must apply an array of other NDE tests to assure or infer the overall set of cable’s system integrity. These cable NDE programs vary in rigor and methodology. As the industry gains experience with the efficacy of these programs, it is expected that implementation practice will converge to a more common approach. This report addresses the range of local NDE cable tests that are

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.

Aging and condition monitoring of electric cables in nuclear power plants

International Nuclear Information System (INIS)

Lofaro, R.J.; Grove, E.; Soo, P.

1998-05-01

There are a variety of environmental stressors in nuclear power plants that can influence the aging rate of components; these include elevated temperatures, high radiation fields, and humid conditions. Exposure to these stressors over long periods of time can cause degradation of components that may go undetected unless the aging mechanisms are identified and monitored. In some cases the degradation may be mitigated by maintenance or replacement. However, some components receive neither and are thus more susceptible to aging degradation, which might lead to failure. One class of components that falls in this category is electric cables. Cables are very often overlooked in aging analyses since they are passive components that require no maintenance. However, they are very important components since they provide power to safety related equipment and transmit signals to and from instruments and controls. This paper will look at the various aging mechanisms and failure modes associated with electric cables. Condition monitoring techniques that may be useful for monitoring degradation of cables will also be discussed

Simultaneous Thermal and Gamma Radiation Aging of Electrical Cable Polymers

Energy Technology Data Exchange (ETDEWEB)

Fifield, Leonard S.

2018-04-11

The polymers used for insulation in nuclear power plant electrical cables are susceptible to aging during long term operation. Elevated temperature is the primary contributor to changes in polymer structure that result loss of mechanical and electrical properties, but gamma radiation is also a significant source of degradation for polymers used within relevant plant locations. Despite many years of polymer degradation research, the combined effects of simultaneous exposure to thermal and radiation stress are not well understood. As nuclear operators contemplate and prepare for extended operations beyond initial license periods, a predictive understanding of exposure-based cable material degradation is becoming an increasingly important input to safety, licensing, operations and economic decisions. We are focusing on carefully-controlled simultaneous thermal and gamma radiation accelerating aging and characterization of the most common nuclear cable polymers to understand the relative contributions of temperature, time, dose and dose rate to changes in cable polymer material structure and properties. Improved understanding of cable performance in long term operation will help support continued sustainable nuclear power generation.

Ageing of cables and new approach for the study of polymer ageing

International Nuclear Information System (INIS)

Monchy-Leroy, C.; Therond, P.

2011-01-01

The study of nuclear cable ageing has become an important subject in particular within the framework of the lifetime extension of nuclear power plants. Until 2000, the approach developed by EDF was a purely empirical one, which establishes from a behavior law, the temporal evolution of a macroscopic property of the jacket or the insulation (generally elongation at break), according to the ageing conditions, such as the temperature and the dose rate. These simulations, coupled with analyses of cables taken on sites after several years of ageing, can demonstrate and justify the good behavior in time of the cables installed in the French nuclear power plants. However from an industrial point of view, this approach, as any empirical approach, is not sustainable and suffers numerous limitations. In particular, the results obtained are not transposable from one industrial formulation to another. That is why for some years, EDF has developed a more generic approach based on the understanding and the modeling of the ageing of polymers by thermo-oxidation and radio-oxidation. This new approach consists of identifying all the occurring reactions at the molecular scale during the polymer ageing. The numerical resolution of the system of differential equations stemming from the scheme of reactions, allows access to the spatial and temporal distributions of the oxidation products formed during the ageing. Today the studies are focused on elastomer matrices of type Polyethylene (PE) and co-polymers of type Ethylene-Propylene-Rubber (EPR) to which were added stabilizers and fillers. Later, the model will allow us to simulate the ageing of any industrial polymer. (authors)

Danida2

DEFF Research Database (Denmark)

Henriksen, Mogens

1996-01-01

At the request of Danish Ministry of Foreign Affairs, Department TSA.4, suggestions for electrical test procedures to determine possibly damaged of a 1-phase, 30 kV XLPE insulated armoured submarine power cable, has been further evaluated.......At the request of Danish Ministry of Foreign Affairs, Department TSA.4, suggestions for electrical test procedures to determine possibly damaged of a 1-phase, 30 kV XLPE insulated armoured submarine power cable, has been further evaluated....

Tailored sPP/Silica Nano composite for Eco friendly Insulation of Extruded HVDC Cable

International Nuclear Information System (INIS)

Dang, B.; He, J.; Hu, J.; Zhou, Y.

2015-01-01

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 eco friendly 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% nano silica. We found that the silica/sPP nano composite without cross-linking offered a suitable mechanical modulus at room temperature and sufficient intensity at high temperatures, and adding nano silica modified by a silane coupling agent to the sPP resulted in significant DC resistivity and space charge improvement. The optimal nano silica content in the sPP was determined by balancing the mechanical and thermomechanical characteristics and the DC resistivity. The sPP/silica nano composite reported here shows great potential as a candidate insulation material for future eco friendly extruded HVDC cables.

Updated Aging Assessment Approach and Use with Electric Cable Insulation

International Nuclear Information System (INIS)

Horvath, David A.; Colaianni, R. Paul

2003-01-01

The service life of nuclear power plant equipment may include operation beyond the original design or qualified life. A technical basis is necessary to demonstrate that critical equipment is capable of continued safe operation for any life extension and renewed license term. Such a technical basis is also useful in addressing initial license term aging degradation, age-related failures, and maintenance issues. Early approaches for addressing aging effects developed for environmental qualification programs in the 1980s were incorporated into the Institute of Electrical and Electronic Engineers' (IEEE) IEEE Std. 1205-1993. However, subsequently, a number of events (including promulgation of the Maintenance Renewal Rule, the new License Renewal Rule, and initial plant owner submittals of License Renewal applications) have resulted in improved aging management approaches, which focus on addressing aging effects rather than attempting to identify and mitigate every possible aging mechanism.An example of a major issue facing nuclear power plants as they mature is the general health of the plant electrical cables. This issue came to the forefront as plants began preparing for license renewal, which requires an evaluation of cables to demonstrate that they will perform their function 20 yr beyond the original 40-yr license period. When the two lead plants started preparing for license renewal, there was no generally accepted approach to the bulk evaluation of plant cables, and there were many who thought it not possible to perform a complete plant cable evaluation. The approaches that emerged from the lead plant reviews demonstrated that an assessment of the general health of plant cables could be performed.IEEE's Nuclear Power Engineering Committee recognized the need to capture these improved approaches. A 2 1/2-yr effort of the IEEE Subcommittee-3 Working Group 3.4 culminating in IEEE Std. 1205-2000 is the consensus of representatives from the two lead license renewal

The Influence of Pre-conditioning on the Space Charge Formation in LDPE and XLPE

DEFF Research Database (Denmark)

Henriksen, Mogens; Holbøll, Joachim T.; Fleming, R.J.

1996-01-01

Planar LDPE and XLPE samples were conditioned by holding in short circuit for 48 hrs. at 40oC under rotary pump pressure, and space charge accumulation in these samples under DC fields of 20 kV/mm was then compared with the corresponding accumulation in unconditioned samples.The test results were...

An Investigation of Corrosion Mitigation Strategies for Aging Post-Tensioned Cables

Science.gov (United States)

2017-01-01

for Aging Post- Tensioned Cables Ernest L. Miller, Barry C. White, Richard W. Haskins, Robert M. Ebeling, and James A. Evans Information Technology...approach walls) using post- tensioning (PT) seven-wire strand cables is a common approach. In the Portland District, for example, 10% of the projects...hydraulic structures by post- tensioned ground anchorage, appreciable loss of capacity in seven-wire strand cables due to corrosion is a reason for concern

An Investigation of Corrosion Mitigation Strategies for Aging Post Tensioned Cables

Science.gov (United States)

2017-01-01

for Aging Post- Tensioned Cables Ernest L. Miller, Barry C. White, Richard W. Haskins, Robert M. Ebeling, and James A. Evans Information Technology...approach walls) using post- tensioning (PT) seven-wire strand cables is a common approach. In the Portland District, for example, 10% of the projects...hydraulic structures by post- tensioned ground anchorage, appreciable loss of capacity in seven-wire strand cables due to corrosion is a reason for concern

A Study of the Equality of Cable Insulations by comparing aging trend using an Oxidation Induction Time Measurement Test

International Nuclear Information System (INIS)

Park, Kyungheum; Bhang, Keugjin; Jeong, Sunchul

2014-01-01

Usually, the environmental qualification test is carried out by the cable manufacturer and the test report is presented while the cable manufacturer supplies the tested cables in nuclear power plant. If a cable manufacturer has environmentally qualified a cable for nuclear power plant more than a decade ago and the composition of the cable material is same, is it acceptable to use the old EQ report for recently manufactured cable? Even though the manufacturer insists the composition of the tested cable and recently manufactured cable's material are same, there can some questions or opposing opinions for two cables, tested cable and recently manufactured cable's equality. In this case, how can I determine the equality for the two cables? It is well known method to use FT-IR to determine the similarity of cable materials. FT-IR is easy tool to compare compositions of each material. But FT-IR method is not proper to compare aging trend of these materials. Oxidation induction time(OIT) testing is a technique that can be used to evaluate aging of organic materials and life assessment technique for cables used in nuclear power plants. In this paper, I studied the OIT technique to compare aging trend for the tested cable and recently manufactured cable to determine the equality for the two cables. To study a equality analysis for cable materials, OIT measurement tests were performed for two cable insulation(produced in 1995 and produced in 2013) which were supplied from same manufacturer. The two cables were irradiated up to 40 Mrad to simulate normal 40 years and thermally aged for 144 hours at 170 .deg. C equals to 40 years qualified life at 90 .deg. C. The OIT measurement were made in order to compare aging trends of the '95 cable and the '13 cable, the test were performed for three sequential steps; initial, after Normal Radiation and after Thermal Aging. The OIT measurement results at the temperature of 225 .deg. C showed very similar degradation

Results of Cable Aging Management Tests for Laguna Verde Nuclear Power Plant

International Nuclear Information System (INIS)

Garcia Hernandez, E.E.; Vazquez Cervantes, R.M.; Bonifacio M, J.; Garcia Garcia, J.

2012-01-01

Laguna Verde Nuclear Power Plant (LVNPP) located in Veracruz, Mexico is a BWR plant, two Units with 810 MWe each one, Unit 1 (1989) and Unit 2 (1990). The Equipment Qualification (EQ) Group at the Nuclear Research National Institute (ININ) has been working with the plant on tasks to develop the LVNPP cables Aging Management Program (AMP), as part of the technical basis to extend the operational life of the plant through license renewal up to 60 years. LVNPP cables are qualified for 40 years plus a LOCA DBA in accordance with 10.CFR 50.49 and the IEEE Std-323 and IEEE St. 383. The first studies for cables AMP have been performed with samples of safety related I and C cables taken from the LVNPP warehouse, similar brands and models as installed at the plant. ININ applied the condition monitoring techniques to these samples to identify predictive degradation and to establish the methodology for cables AMP, focused to the LVNPP license renewal. Cable tests program has been running at the EQ Lab in ININ, performing accelerated aging by steps up to 60 years and to 40 years plus a LOCA test. Determination for Activation Energy (Ea) and Oxidation Induction Time (OIT) methods were developed applying a DSC/TGA calorimeter. (author)

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

Study of the experience feedback relating to ageing of electronic components and cables

International Nuclear Information System (INIS)

Gauthier, G.; Henry, J.Y.

1992-11-01

This study was conducted on electronic components and electrical cables taken from the Brennilis EL4 reactor, during dismantling, after 18 years of operation. Its aim was to examine the state of the equipment taken from the site and thus to check its characteristics and in particular for cables: to check, whenever possible, the suitability of the accelerated ageing methods by comparing the characteristics observed on the samples from EL4 with test samples held in storage and previously subjected to similar accelerated ageing: predicting medium and long-term ageing by extrapolation from the selected mathematical model. The result of this initial work confirmed the need for extreme caution regarding the accelerated ageing methods. Further work on cables and polymers is underway and will enable the laws currently used for qualification tests to be evaluated

Effects evaluation of artificial aging by temperature and gamma radiation on cables for Laguna Verde nuclear power plant (LVNPP)

Energy Technology Data Exchange (ETDEWEB)

Vazquez C, R. M.; Bonifacio M, J.; Garcia H, E. E.; Loperena Z, J. A. [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico); Garcia M, C., E-mail: raulmario.vazquez@inin.gob.m [CFE, Central Nuclear Laguna Verde, Km. 42.5 Carretera Cardel-Nautla, Veracruz (Mexico)

2010-10-15

A set of tests has been carried out at the Equipment Qualification Laboratory at National Institute of Nuclear Research to perform accelerated aging up to 60 years under temperature and gamma radiation environment for electrical cables. The results obtained from such tests are the base line data for comparison to with the current cable conditions at the plant. This work is intended for establishing the cable aging management program for the Laguna Verde nuclear power plant (LVNPP). For such purpose, the Institute has prepared methodologies and procedures to apply condition monitoring techniques in accelerated aging tests on samples of new cables drawn from the LVNPP warehouse. The condition indicators of the material selected for condition monitoring and the aging management process of cables were: Elongation at Break (EAB) and Oxidation Induction Time (OIT). A cable aging management program includes activities for cable selection, determination of condition indicators of the cable materials (EAB, OIT, Ind enter), accelerated aging of cable samples at the laboratory, analysis of maintenance history, operational experience of the plant and analysis of the environmental and service conditions (temperature and gamma radiation), as well as the establishment of a condition monitoring plan for cables in the plant. Two cable model samples were thermally aged and gamma irradiated with doses corresponding to differential operational periods. EAB and OIT values of cable insulating material (ethylene propylene and cross linked polyethylene) were obtained. It was found that the EAB and OIT data correlation is very closed, and it could be applied to infer values that are not possible to measure directly at the plant and be used for cable aging evaluation and remaining life time determination. (Author)

Study of the experience feedback relating to ageing of electronic component and cables

International Nuclear Information System (INIS)

Gauthier, G.; Henry, J.Y.

1992-11-01

This study was conducted on electronic components and electrical cables taken from the Brennilis EL4 reactor, during dismantling, after 18 years of operation. Its aim was to examine the state of the equipment taken from the site and thus to check its characteristics and in particular for cables: to check, whenever possible, the suitability of the accelerated ageing methods by comparing the characteristics observed on the samples from EL4 with test samples held in storage and previously subjected to similar accelerated ageing: predicting medium and long-term ageing by extrapolation from the selected mathematical model. The result of this initial work confirmed the need for extreme caution regarding the accelerated ageing methods. Further work on cables and polymers is underway and will enable the laws currently used for qualification tests to be evaluated. (author) [fr

Ageing Management Programs for Electrical Cables in Slovak NPPs

International Nuclear Information System (INIS)

Rovny, Karol

2012-01-01

One of the key factors, which are negatively affecting the operational safety of nuclear power plants, is the process of ageing. The need for the elimination of these ageing related damages is self-evident and naturally of the highest priority, to preserve the operational safety and reliability. Keeping in mind the safety and reliability of operated devices, and on the other hand the effort to maximize the device utilization, it is recommended to introduce and implement the programs for the monitoring and management of ageing of individual systems, structures and components (SSC). These shall ensure the possibility to monitor and evaluate the effects of degeneration processes on the selected SSC's , to monitor the trends in the parameters measured and ensure the adoption of appropriate corrective actions in real time. The number of nuclear reactors, which are exceeding the originally assumed operational longevity, as defined by original project documentation, is rapidly increasing. It is to no surprise that the demand for their extended operational longevity is increasing hand in hand with the strengthening safety and regulatory requirements worldwide. Each nuclear power plant consists of, among others, kilometers and miles of electric and I and C cables. Their task is irreplaceable, and their excellent condition is vital for the safety and reliability of seamless power plant operation. Thus it is critical and essential to recognize and monitor the real performance of the cables, and to implement programs, which monitor their actual condition. A successful implementation of ageing programs is a cornerstone of safe power plant operations in a long run. The focus of this presented paper is the defined approach, stated goals, and the results achieved in the area of cable ageing and longevity monitoring in the environment of Slovak nuclear power plants.

Aging, condition monitoring, and loss-of-coolant accident (LOCA) tests of class 1E electrical cables

International Nuclear Information System (INIS)

Jacobus, M.J.

1992-11-01

This report describes the results of aging, condition monitoring, and accident testing of miscellaneous cable types. Three sets of cables were aged for up to 9 months under simultaneous thermal (≅100 degrees C) and radiation (≅0.10 kGy/hr) conditions. A sequential accident consisting of high dose rate irradiation (≅6 kGy/hr) and high temperature steam followed the aging. Also exposed to the accident conditions was a fourth set of cables, which were unaged. The test results indicate that, properly installed, most of the various miscellaneous cable products tested should be able to survive an accident after 60 years for total aging doses of at least 150 kGy or higher (depending on the material) and for moderate ambient temperatures on the order of 45--55 degrees C (potentially higher or lower, depending on material specific activtion energies and total radiation doses). Mechanical measurements (primarily elongation, modulus, and density) were more effective than electrical measurements for monitoring age-related degradation

SCAP: the Nea project on stress corrosion cracking and cable ageing

International Nuclear Information System (INIS)

Yamamoto, A.; Huerta, A.; Gott, K.; Koshy, T.

2007-01-01

Two subjects - stress corrosion cracking (SCC) and degradation of cable insulation - were selected as the focus of the SCC and Cable Ageing Project (SCAP) due to their relevance for plant ageing assessments and their implication on inspection practices. Fourteen NEA member countries agreed to contribute to the project. The main SCAP objectives are to: establish a complete database with regard to major ageing phenomena for SCC and degradation of cable insulation through collective efforts by OECD/NEA members; establish a knowledge base in these areas by compiling and evaluating the collected data and information systematically; perform an assessment of the data and identify the basis for commendable practices which would help regulators and operators to enhance ageing management. The aim of the knowledge base is to provide a state-of-the-art description of the degradation mechanisms, the main influencing factors, the most susceptible materials and locations, and common strategies available for mitigation and repair. The SCAP project is currently in the development phase, defining and refining the database performance requirements, data format and coding guidelines. The project is scheduled to last four years. It is anticipated that the database definition and the collection of data from member countries will take approximately two years. The subsequent assessment and the commendable practices report are expected to take one year each

Results of Recent DOE Research on Development of Cable Condition Monitoring and Aging Management Technologies

International Nuclear Information System (INIS)

Campbell, C.J.; McConkey, J.B.; Hashemian, H.M.; Sexton, C.D.; Cummins, D.S.

2012-01-01

Analysis and Measurement Services (AMS) Corporation has been conducting two research projects focused on understanding cable aging and developing cable condition monitoring technologies for nuclear power plants. The goal of the first project is to correlate cable faults with testing techniques that can identify and locate the faults whether they are in the cable, conductor, or the insulation. This project involves laboratory experiments using low and medium voltage cable types typically installed in nuclear power plants. The second project is focused on development of an integrated cable condition monitoring system for nuclear facilities. This system integrates a number of cable testing and cable condition monitoring techniques, such as the time domain reflectometry (TDR), frequency domain reflectometry (FDR), inductance, capacitance, resistance (LCR), reverse TDR (RTDR), current-to-voltage (IV) for testing of nuclear instrumentation sensors, insulation resistance (IR) and other techniques. The purpose of the project is to combine all proven technologies into one system to detect and pinpoint problems in cable circuits as well as cable insulation, shield, or jacket material. (author)

A review of electric cable aging effects and monitoring programs for plant license renewal

International Nuclear Information System (INIS)

Lofaro, R.J.

1999-01-01

As commercial nuclear power plants approach the end of their original license period, some utilities are considering the possibility of license renewal. The requirements for applying for license renewal are specified in the License Renewal Rule, which is in Title 10 of the Code of Federal Regulations, Part 54 (10 CFR54). Among the requirements specified in the rule is the performance of an Integrated Plant Assessment (IPA) which identifies and lists structures and components subject to an aging management review. The intent of this requirement is to ensure that aging degradation will not adversely affect plant safety during the license renewal period. The aging management review includes an identification of the aging effects and monitoring programs for components within the scope of the rule. Among the components within the scope are electric cables since they are passive, long-lived components that are not replaced on a periodic basis. This paper examines the aging causes and effects of electric cables, along with the programs that are typically used to ensure that proper aging management practices are in place to monitor and mitigate the effects of aging on electric cables

Calculation of Activation Energy by OIT Method for aging evaluation of NPP cable

International Nuclear Information System (INIS)

Park, Kyung-Heun; Kim, Jong-Seog; Cho, Bok-Gee

2006-01-01

Extending the lifetime of nuclear power plant is one of the most important concerns in the world nuclear industry. Cables are one of the long live items which have not been considered to be replaced during the design life of NPP. In order to simulate the natural aging in nuclear power plant, a study on accelerated aging needs to be conducted and to carry out the accelerated aging test, we must calculate the activation energy of the cable if we don't have the activation energy information. The activation energy is the most important element and it can be calculated by indentor modulus and elongation data and so on. But there is often only a limited quantity of material available in the deposit for testing, so it is important the samples for any destructive test are conserved as much as possible. But if there is only a limited quantity of the material, OIT(Oxidation Induction Time) is very useful with calculating activation energy and evaluation of the cable lifetime

DC Model Cable under Polarity Inversion and Thermal Gradient: Build-Up of Design-Related Space Charge

Directory of Open Access Journals (Sweden)

Nugroho Adi

2017-07-01

Full Text Available In the field of energy transport, High-Voltage DC (HVDC technologies are booming at present due to the more flexible power converter solutions along with needs to bring electrical energy from distributed production areas to consumption sites and to strengthen large-scale energy networks. These developments go with challenges in qualifying insulating materials embedded in those systems and in the design of insulations relying on stress distribution. Our purpose in this communication is to illustrate how far the field distribution in DC insulation systems can be anticipated based on conductivity data gathered as a function of temperature and electric field. Transient currents and conductivity estimates as a function of temperature and field were recorded on miniaturized HVDC power cables with construction of 1.5 mm thick crosslinked polyethylene (XLPE insulation. Outputs of the conductivity model are compared to measured field distributions using space charge measurements techniques. It is shown that some features of the field distribution on model cables put under thermal gradient can be anticipated based on conductivity data. However, space charge build-up can induce substantial electric field strengthening when materials are not well controlled.

Summary Report of Cable Aging and Performance Data for Fiscal Year 2014.

Energy Technology Data Exchange (ETDEWEB)

Celina, Mathias C.; Celina, Mathias C.; Redline, Erica Marie; Redline, Erica Marie; Bernstein, Robert; Bernstein, Robert; Quintana, Adam; Quintana, Adam; Giron, Nicholas Henry; Giron, Nicholas Henry; White II, Gregory Von; White II, Gregory Von

2014-09-01

As part of the Light Water Reactor Sustainability Program, science - based engineering approaches were employed to address cable degradation behavior under a range of exposure environments. Experiments were conducted with the goal to provide best guidance for aged material states, remaining life and expected performance under specific conditions for a range of cable materials. Generic engineering tests , which focus on rapid accelerated aging and tensile elongation , were combined with complementar y methods from polymer degradation science. Sandia's approach, building on previous years' efforts, enabled the generation of some of the necessary data supporting the development of improved lifetime predictions models, which incorporate known material b ehaviors and feedback from field - returned 'aged' cable materials. Oxidation rate measurements have provided access to material behavior under low dose rate thermal conditions, where slow degradation is not apparent in mechanical property changes. Such da ta have shown aging kinetics consistent with established radiati on - thermal degradation models. ACKNOWLEDGEMENTS We gratefully acknowledge ongoing technical support at the LICA facility and extensive sample handling provided by Maryla Wasiolek and Don Hans on. Sam Durbin and Patrick Mattie are recognized for valuable guidance throughout the year and assistance in the preparation of the final report. Doug Brunson is appreciated for sample analysis, compilation and plotting of experimental data.

Assessment of Cable Aging Equipment, Status of Acquired Materials, and Experimental Matrix at the Pacific Northwest National Laboratory

Energy Technology Data Exchange (ETDEWEB)

Fifield, Leonard S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Westman, Matthew P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Zwoster, Andy [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Schwenzer, Birgit [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2015-03-30

The need for increased understanding of the aging and degradation behavior for polymer components of nuclear power plant electrical cables is described in this report. The highest priority materials for study and the resources available at PNNL for these studies are also described. The anticipated outcomes of the PNNL work described are : improved understanding of appropriate accelerated aging conditions, improved knowledge of correlation between observable aging indicators and cable condition in support of advanced non-destructive evaluation methods, and practical knowledge of condition-based cable lifetime prediction.

Wear performance of neat and vitamin E blended highly cross-linked PE under severe conditions: The combined effect of accelerated ageing and third body particles during wear test.

Science.gov (United States)

Affatato, Saverio; De Mattia, Jonathan Salvatore; Bracco, Pierangiola; Pavoni, Eleonora; Taddei, Paola

2016-12-01

The objective of this study is to evaluate the effects of third-body particles on the in vitro wear behaviour of three different sets of polyethylene acetabular cups after prolonged testing in a hip simulator and accelerated ageing. Vitamin E-blended, cross-linked polyethylene (XLPE_VE), cross-linked polyethylene (XLPE) and conventional polyethylene (STD_PE) acetabular cups were simulator tested for two million cycles under severe conditions (i.e. by adding third-body particles to the bovine calf serum lubricant). Micro-Fourier Transform Infrared and micro-Raman spectroscopic analyses, differential scanning calorimetry, and crosslink density measurements were used to characterize the samples at a molecular level. The STD_PE cups had twice mass loss than the XLPE_VE components and four times than the XLPE samples; statistically significant differences were found between the mass losses of the three sets of cups. The observed wear trend was justified on the basis of the differences in cross-link density among the samples (XLPE>XLPE_VE>STD_PE). FTIR crystallinity profiles, bulk DSC crystallinity and surface micro-Raman crystallinity seemed to have a similar behaviour upon testing: all of them (as well as the all-trans and ortho-trans contents) revealed the most significant changes in XLPE and XLPE_VE samples. The more severe third-body wear testing conditions determined more noticeable changes in all spectroscopic markers with respect to previous tests. Unexpectedly, traces of bulk oxidation were found in both STD_PE (unirradiated) and XLPE (remelting-stabilized), which were expected to be stable to oxidation; on the contrary, XLPE_VE demonstrated a high oxidative stability in the present, highly demanding conditions. Copyright © 2016 Elsevier Ltd. All rights reserved.

Life evaluation of FR-CV cable on thermal-radiation combined aging by micro-hardness

International Nuclear Information System (INIS)

Sugiyama, Masahiko; Ogata, Akimasa; Nitta, Makoto; Tani, Tsuneo; Yagi, Toshiaki; Seguchi, Tadao.

1996-01-01

For the evaluation of cable life for the application to nuclear facilities, the accelerated test was conducted by the combination of radiation and thermal oxidation. The degradation of FR-CV cable by the aging was monitored by tensile test, micro-hardness test, and gel-fraction measurement. The micro-hardness increased with the progress of degradation and related well with decrease of ultimate elongation of the sheath material, and was also reflected by the loss of plasticizer. The micro-hardness technique has a possibility to detect the degradation of cable as a non-destructive detector. (author)

Improving regulatory practices through the OECD-NEA Stress Corrosion Cracking and Cable Ageing Project (SCAP)

International Nuclear Information System (INIS)

Yamamoto, A.; Huerta, A.; Sekimura, N.; Gott, K.; Koshy, T.

2012-01-01

For regulatory authorities, it is important to verify the adequacy of ageing management methods applied by the licensees, based on reliable technical evidence. In order to achieve that goal, 14 NEA member countries joined the SCAP (Project) in 2006 to share knowledge and three more countries joined during the course of the project. The project focused on two important safety issues, the stress corrosion cracking (SCC) and the degradation of cable insulation, due to their relevance for plant ageing assessments and their implication on inspection practices. The commendable practices identified in the project are intended to strengthen technical approaches to optimize ageing management in the areas of SCC and cable ageing. The SCAP SCC and Cable data- and knowledge bases provided extensive information to benefit all stakeholders in designing, constructing, operating and regulating Nuclear Power Plants and also provide commendable practices applicable to new reactors. The paper presents the product of SCAP work resulting from 4 years of technical interactions and shared knowledge from all participants from June 2006 to June 2010. (author)

Charge Accumulation in LDPE and XLPE Conditioned at 80oC under Reduced Pressure

DEFF Research Database (Denmark)

Fleming, Robert J.; Henriksen, Mogens; Holbøll, Joachim T.

1997-01-01

The effects of thermal conditioning, under reduced pressure, on space accumulation in planar LDPE and XLPE samples under DC stress, have been investigated. The samples were conditioned prior to voltage application by being held at 80oC for 2-3 days in short circuit at rotary pump pressure. Some...... were then cooled to room temperature over a period of at least 6hr, still under rotary pump pressure and in short circuit, while others were cooled to room temperature in less than 1.5hr in the laboratory air. DC fields of 18kV/mm were then applied at room temperature, and space charge accumulation...

Superheated-steam test of ethylene propylene rubber cables using a simultaneous aging and accident environment

International Nuclear Information System (INIS)

Bennett, P.R.; St Clair, S.D.; Gilmore, T.W.

1986-06-01

The superheated-steam test exposed different ethylene propylene rubber (EPR) cables and insulation specimens to simultaneous aging and a 21-day simultaneous accident environment. In addition, some insulation specimens were exposed to five different aging conditions prior to the 21-day simultaneous accident simulation. The purpose of this superheated-steam test (a follow-on to the saturated-steam tests (NUREG/CR-3538)) was to: (1) examine electrical degradation of different configurations of EPR cables; (2) investigate differences between using superheated-steam or saturated-steam at the start of an accident simulation; (3) determine whether the aging technique used in the saturated-steam test induced artificial degradation; and (4) identify the constituents in EPR that affect moisture absorption

Determining Remaining Useful Life of Aging Cables in Nuclear Power Plants - Interim Study FY13

International Nuclear Information System (INIS)

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

2013-01-01

warning of aging and degradation. Examples of such key indicators include changes in chemical structure, mechanical modulus, and dielectric permittivity. While some of these indicators are the basis of currently used technologies, there is a need to increase the volume of cable that may be inspected with a single measurement, and if possible, to develop techniques for in-situ inspection (i.e., while the cable is in operation). This is the focus of the present report

State of the Art Assessment of NDE Techniques for Aging Cable Management in Nuclear Power Plants FY2015

Energy Technology Data Exchange (ETDEWEB)

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

2015-09-08

This milestone report presents an update on the state-of-the-art review and research being conducted to identify key indicators of in-containment cable aging at nuclear power plants (NPPs), and devise in-situ measurement techniques that are sensitive to these key indicators. The motivation for this study stems from the need to address open questions related to nondestructive evaluation (NDE) of aging cables for degradation detection and estimation of condition-based remaining service life. These questions arise within the context of a second round of license extension for NPPs that would extend the operating license to 60 and 80 years. Within the introduction, a review of recently published U.S. and international research and guidance for cable aging management programs including NDE technologies is provided. As with any “state-of-the-art” report, the observations are deemed accurate as of the publication date but cannot anticipate evolution of the technology. Moreover, readers are advised that research and development of cable NDE technology is an ongoing issue of global concern.

State of the Art Assessment of NDE Techniques for Aging Cable Management in Nuclear Power Plants FY2015

International Nuclear Information System (INIS)

Glass, Samuel W.; Fifield, Leonard S.; Dib, Gerges; Tedeschi, Jonathan R.; Jones, Anthony M.; Hartman, Trenton S.

2015-01-01

This milestone report presents an update on the state-of-the-art review and research being conducted to identify key indicators of in-containment cable aging at nuclear power plants (NPPs), and devise in-situ measurement techniques that are sensitive to these key indicators. The motivation for this study stems from the need to address open questions related to nondestructive evaluation (NDE) of aging cables for degradation detection and estimation of condition-based remaining service life. These questions arise within the context of a second round of license extension for NPPs that would extend the operating license to 60 and 80 years. Within the introduction, a review of recently published U.S. and international research and guidance for cable aging management programs including NDE technologies is provided. As with any 'state-of-the-art' report, the observations are deemed accurate as of the publication date but cannot anticipate evolution of the technology. Moreover, readers are advised that research and development of cable NDE technology is an ongoing issue of global concern.

Aging predictions in nuclear power plants: Crosslinked polyolefin and EPR cable insulation materials

International Nuclear Information System (INIS)

Gillen, K.T.; Clough, R.L.

1991-06-01

In two earlier reports, we derived a time-temperature-dose rate superposition methodology, which, when applicable, can be used to predict cable degradation versus dose rate, temperature and exposure time. This methodology results in long-term predictive capabilities at the low dose rates appropriate to ambient nuclear power plant aging environments. The methodology was successfully applied to numerous important cable materials used in nuclear applications and the extrapolated predictions were verified by comparisons with long-term (7 to 12 year) results for similar or identical materials aged in nuclear environments. In this report, we test the methodology on three crosslinked polyolefin (CLPO) and two ethylene propylene rubber (EPR) cable insulation materials. The methodology applies to one of the CLPO materials and one of the EPR materials, allowing predictions to be made for these materials under low dose-rate, low temperature conditions. For the other materials, it is determined that, at low temperatures, a decrease in temperature at a constant radiation dose rate leads to an increase in the degradation rate for the mechanical properties. Since these results contradict the fundamental assumption underlying time-temperature-dose rate superposition, this methodology cannot be applied to such data. As indicated in the earlier reports, such anomalous results might be expected when attempting to model data taken across the crystalline melting region of semicrystalline materials. Nonetheless, the existing experimental evidence suggests that these CLPO and EPR materials have substantial aging endurance for typical reactor conditions. 28 refs., 26 figs., 3 tabs

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

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

warning of aging and degradation. Examples of such key indicators include changes in chemical structure, mechanical modulus, and dielectric permittivity. While some of these indicators are the basis of currently used technologies, there is a need to increase the volume of cable that may be inspected with a single measurement, and if possible, to develop techniques for in-situ inspection (i.e., while the cable is in operation). This is the focus of the present report.

Benchmark Analysis for Condition Monitoring Test Techniques of Aged Low Voltage Cables in Nuclear Power Plants. Final Results of a Coordinated Research Project

International Nuclear Information System (INIS)

2017-10-01

This publication provides information and guidelines on how to monitor the performance of insulation and jacket materials of existing cables and establish a programme of cable degradation monitoring and ageing management for operating reactors and the next generation of nuclear facilities. This research was done through a coordinated research project (CRP) with participants from 17 Member States. This group of experts compiled the current knowledge in a report together with areas of future research and development to cover aging mechanisms and means to identify and manage the consequences of aging. They established a benchmarking programme using cable samples aged under thermal and/or radiation conditions, and tested before and after ageing by various methods and organizations. In particular, 12 types of cable insulation or jacket material were tested, each using 14 different condition monitoring techniques. Condition monitoring techniques yield usable and traceable results. Techniques such as elongation at break, indenter modulus, oxidation induction time and oxidation induction temperature were found to work reasonably well for degradation trending of all materials. However, other condition monitoring techniques, such as insulation resistance, were only partially successful on some cables and other methods like ultrasonic or Tan δ were either unsuccessful or failed to provide reliable information to qualify the method for degradation trending or ageing assessment of cables. The electrical in situ tests did not show great promise for cable degradation trending or ageing assessment, although these methods are known to be very effective for finding and locating faults in cable insulation material. In particular, electrical methods such as insulation resistance and reflectometry techniques are known to be rather effective for locating insulation damage, hot spots or other faults in essentially all cable types. The advantage of electrical methods is that they can be

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.

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.

Review of candidate methods for detecting incipient defects due to aging of installed cables in nuclear power plants

International Nuclear Information System (INIS)

Martzloff, F.D.

1988-01-01

Several types of test methods have been proposed for detecting incipient defects due to aging in cable insulation systems, none offering certainty of detecting all possible types of defects. Some methods apply direct detection of a defect in the cable; other methods detect changes in electrical or non-electrical parameters from which inference can be drawn on the integrity of the cable. The paper summarizes the first year of a program conducted at the National Bureau of Standards to assess the potential of success for in situ detection of incipient defects by the most promising of these methods

Investigating the burning characteristics of electric cables used in the nuclear power plant by way of 3-D transient FDS code

Energy Technology Data Exchange (ETDEWEB)

Ferng, Y.M., E-mail: ymferng@ess.nthu.edu.t [Department of Engineering and System Science, Institute of Nuclear Engineering and Science, National Tsing Hua University, 101, Sec. 2. Kuang-Fu Rd., Hsinchu 30013, Taiwan (China); Liu, C.H. [Department of Engineering and System Science, Institute of Nuclear Engineering and Science, National Tsing Hua University, 101, Sec. 2. Kuang-Fu Rd., Hsinchu 30013, Taiwan (China)

2011-01-15

Burning characteristics of electrical cables are one of the key parameters for the fire hazard assessment of nuclear power plants (NPPs) since the cables are the essential sources of fire in the plants. A three-dimensional (3-D) transient computational fluid dynamics (CFD) code{sub F}DS is adopted in this paper to simulate these characteristics related to the cable burning. Being one of the NRC licensing fire codes, the FDS includes the thermal-hydraulic equations, the turbulence model and the chemical combustion model, etc. In order to assess the CFD fire models used in this code, a burning test using the control cable with the outer jacket of polyvinylchloride (PVC) and the inner insulation of cross-linked polyethylene (XLPE) is conducted. The measured parameters associated with the burning characteristics include the heat release rate (HRR), O{sub 2} depletion, and CO and CO{sub 2} production, etc. Except the amount of O{sub 2} consumption, the predicted transient behaviors of other parameters can reproduce the measured data. Based on the chemical combustion model in the FDS code, this discrepancy may be essentially resulted from the default value of hydrogen fraction (H{sub frac}) contained in the soot since the soot yield for the burning of PVC material is high enough that the uncertainty in the H{sub frac} value has a prominent effect on the amount of O{sub 2} consumption. This explanation can be confirmed by a benchmark calculation for simulating a burning test with the polymethylmethacrylate (PMMA) fuel of low-soot yield. The present simulation works can provide the useful information for the plant staff or the researcher as they would perform the fire hazard analysis in the NPPs using the FDS code.

OTEC riser cable model and prototype testing

Science.gov (United States)

Kurt, J. P.; Schultz, J. A.; Roblee, L. H. S.

1981-12-01

Two different OTEC riser cables have been developed to span the distance between a floating OTEC power plant and the ocean floor. The major design concerns for a riser cable in the dynamic OTEC environment are fatigue, corrosion, and electrical/mechanical aging of the cable components. The basic properties of the cable materials were studied through tests on model cables and on samples of cable materials. Full-scale prototype cables were manufactured and were tested to measure their electrical and mechanical properties and performance. The full-scale testing was culminated by the electrical/mechanical fatigue test, which exposes full-scale cables to simultaneous tension, bending and electrical loads, all in a natural seawater environment.

Similarity Analysis of Cable Insulations by Chemical Test

Energy Technology Data Exchange (ETDEWEB)

Kim, Jong Seog [Central Research Institute of Korea Hydro and Nuclear Power Co., Daejeon (Korea, Republic of)

2013-10-15

As result of this experiment, it was found that FT-IR test for material composition, TGA test for aging trend are applicable for similarity analysis of cable materials. OIT is recommended as option if TGA doesn't show good trend. Qualification of new insulation by EQ report of old insulation should be based on higher activation energy of new insulation than that of old one in the consideration of conservatism. In old nuclear power plant, it is easy to find black cable which has no marking of cable information such as manufacturer, material name and voltage. If a type test is required for qualification of these cables, how could I select representative cable? How could I determine the similarity of these cables? If manufacturer has qualified a cable for nuclear power plant more than a decade ago and composition of cable material is changed with similar one, is it acceptable to use the old EQ report for recently manufactured cable? It is well known to use FT-IR method to determine the similarity of cable materials. Infrared ray is easy tool to compare compositions of each material. But, it is not proper to compare aging trend of these materials. Study for similarity analysis of cable insulation by chemical test is described herein. To study a similarity evaluation method for polymer materials, FT-IR, TGA and OIT tests were performed for two cable insulation(old and new) which were supplied from same manufacturer. FT-IR shows good result to compare material compositions while TGA and OIT show good result to compare aging character of materials.

Similarity Analysis of Cable Insulations by Chemical Test

International Nuclear Information System (INIS)

Kim, Jong Seog

2013-01-01

As result of this experiment, it was found that FT-IR test for material composition, TGA test for aging trend are applicable for similarity analysis of cable materials. OIT is recommended as option if TGA doesn't show good trend. Qualification of new insulation by EQ report of old insulation should be based on higher activation energy of new insulation than that of old one in the consideration of conservatism. In old nuclear power plant, it is easy to find black cable which has no marking of cable information such as manufacturer, material name and voltage. If a type test is required for qualification of these cables, how could I select representative cable? How could I determine the similarity of these cables? If manufacturer has qualified a cable for nuclear power plant more than a decade ago and composition of cable material is changed with similar one, is it acceptable to use the old EQ report for recently manufactured cable? It is well known to use FT-IR method to determine the similarity of cable materials. Infrared ray is easy tool to compare compositions of each material. But, it is not proper to compare aging trend of these materials. Study for similarity analysis of cable insulation by chemical test is described herein. To study a similarity evaluation method for polymer materials, FT-IR, TGA and OIT tests were performed for two cable insulation(old and new) which were supplied from same manufacturer. FT-IR shows good result to compare material compositions while TGA and OIT show good result to compare aging character of materials

Cable condition monitoring in a pressurized water reactor environment

International Nuclear Information System (INIS)

Al-Hussaini, T.J.

1988-01-01

Oconee Nuclear Station is the first nuclear plant designed, engineered and constructed by Duke Power Company. Even though the accelerated aging method was available to determine the life expectancy of the cable used in the reactor building, no natural aging data was available at that time. In order to be able to verify the condition of the reactor building cable over the life of the plant, an on-going cable monitoring plan was instituted. Various types of cable were selected to be monitored, and they were installed in cable life evaluation circuits in the reactor building. At five year intervals over the life of the plant, cable samples would be removed from these cable life evaluation circuits and tested to determine the effects of the reactor building environment on the integrity of the cable. A review of the cable life evaluation circuits and the results of the evaluation program to date is presented

Experimental Study on Behavior of Bow-tie Tree Generation by Using Heavy Water

Science.gov (United States)

Kumazawa, Takao; Nakagawa, Wataru; Tsurumaru, Hidekazu

Bow-tie tree (BTT) generated from contaminant, e.g., metal, carbon, amber(over cured resin) or void in insulator is a significant deterioration factor of XLPE power cable. However, essential role of water in generation and progress of BTT is not yet sufficiently cleared. In order to investigate the role of water we paid attention to difference in chemical properties of light water (H2O) and heavy water (D2O), moreover we evaluated influence of isotopic effect due to hydrogen and deuterium on behavior of BTT generation. In accelerated aging test the number of BTT in XLPE sample, in which copper powder of 500ppm was contaminated as BTT cores, dipped in heavy water (D2O:100wt%) decreased to one third compared with light water(D2O:0wt%). Furthermore, the maximum length of BTT decreased with increase in concentration of heavy water. The experimental results show that heavy water exerted a depression effect on generation and progress of BTT. We considered that the depression effect due to hydrogen isotope appeared by inhibiting ionization and elution of BTT cores, because salt-solubility and ionic mobility of heavy water are about 15 to 20% smaller than those of light water. Therefore, the essential role of water seemed to be production and transport of ions in XLPE.

Review of nuclear power plant safety cable aging studies with recommendations for improved approaches and for future work

International Nuclear Information System (INIS)

Gillen, Kenneth Todd; Bernstein, Robert

2010-01-01

Many U. S. nuclear power plants are approaching 40 years of age and there is a desire to extend their life for up to 100 total years. Safety-related cables were originally qualified for nuclear power plant applications based on IEEE Standards that were published in 1974. The qualifications involved procedures to simulate 40 years of life under ambient power plant aging conditions followed by simulated loss of coolant accident (LOCA). Over the past 35 years or so, substantial efforts were devoted to determining whether the aging assumptions allowed by the original IEEE Standards could be improved upon. These studies led to better accelerated aging methods so that more confident 40-year lifetime predictions became available. Since there is now a desire to potentially extend the life of nuclear power plants way beyond the original 40 year life, there is an interest in reviewing and critiquing the current state-of-the-art in simulating cable aging. These are two of the goals of this report where the discussion is concentrated on the progress made over the past 15 years or so and highlights the most thorough and careful published studies. An additional goal of the report is to suggest work that might prove helpful in answering some of the questions and dealing with some of the issues that still remain with respect to simulating the aging and predicting the lifetimes of safety-related cable materials.

Automated Cable Preparation for Robotized Stator Cable Winding

Directory of Open Access Journals (Sweden)

Erik Hultman

2017-04-01

Full Text Available A method for robotized cable winding of the Uppsala University Wave Energy Converter generator stator has previously been presented and validated. The purpose of this study is to present and validate further developments to the method: automated stand-alone equipment for the preparation of the winding cables. The cable preparation consists of three parts: feeding the cable from a drum, forming the cable end and cutting the cable. Forming and cutting the cable was previously done manually and only small cable drums could be handled. Therefore the robot cell needed to be stopped frequently. The new equipment was tested in an experimental robot stator cable winding setup. Through the experiments, the equipment was validated to be able to perform fully automated and robust cable preparation. Suggestions are also given on how to further develop the equipment with regards to performance, robustness and quality. Hence, this work represents another important step towards demonstrating completely automated robotized stator cable winding.

Comparison of Conductor-Temperature Calculations Based on Different Radial-Position-Temperature Detections for High-Voltage Power Cable

Directory of Open Access Journals (Sweden)

Lin Yang

2018-01-01

Full Text Available In this paper, the calculation of the conductor temperature is related to the temperature sensor position in high-voltage power cables and four thermal circuits—based on the temperatures of insulation shield, the center of waterproof compound, the aluminum sheath, and the jacket surface are established to calculate the conductor temperature. To examine the effectiveness of conductor temperature calculations, simulation models based on flow characteristics of the air gap between the waterproof compound and the aluminum are built up, and thermocouples are placed at the four radial positions in a 110 kV cross-linked polyethylene (XLPE insulated power cable to measure the temperatures of four positions. In measurements, six cases of current heating test under three laying environments, such as duct, water, and backfilled soil were carried out. Both errors of the conductor temperature calculation and the simulation based on the temperature of insulation shield were significantly smaller than others under all laying environments. It is the uncertainty of the thermal resistivity, together with the difference of the initial temperature of each radial position by the solar radiation, which led to the above results. The thermal capacitance of the air has little impact on errors. The thermal resistance of the air gap is the largest error source. Compromising the temperature-estimation accuracy and the insulation-damage risk, the waterproof compound is the recommended sensor position to improve the accuracy of conductor-temperature calculation. When the thermal resistances were calculated correctly, the aluminum sheath is also the recommended sensor position besides the waterproof compound.

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

Choice Of Computer Networking Cables And Their Effect On Data ...

African Journals Online (AJOL)

Computer networking is the order of the day in this Information and Communication Technology (ICT) age. Although a network can be through a wireless device most local connections are done using cables. There are three main computer-networking cables namely coaxial cable, unshielded twisted pair cable and the optic ...

Light Water Reactor Sustainability (LWRS) Program – Non-Destructive Evaluation (NDE) R&D Roadmap for Determining Remaining Useful Life of Aging Cables in Nuclear Power Plants

Energy Technology Data Exchange (ETDEWEB)

Simmons, Kevin L.; Ramuhalli, Pradeep; Brenchley, David L.; Coble, Jamie B.; Hashemian, Hash; Konnik, Robert; Ray, Sheila

2012-09-14

The purpose of the non-destructive evaluation (NDE) R&D Roadmap for Cables is to support the Materials Aging and Degradation (MAaD) R&D pathway. The focus of the workshop was to identify the technical gaps in detecting aging cables and predicting their remaining life expectancy. The workshop was held in Knoxville, Tennessee, on July 30, 2012, at Analysis and Measurement Services Corporation (AMS) headquarters. The workshop was attended by 30 experts in materials, electrical engineering, U.S. Nuclear Regulatory Commission (NRC), U.S. Department of Energy (DOE) National Laboratories (Oak Ridge National Laboratory, Pacific Northwest National Laboratory, Argonne National Laboratory, and Idaho National Engineering Laboratory), NDE instrumentation development, universities, commercial NDE services and cable manufacturers, and Electric Power Research Institute (EPRI). The motivation for the R&D roadmap comes from the need to address the aging management of in-containment cables at nuclear power plants (NPPs).

State of the art in power cable design, failure mechanisms and testing

International Nuclear Information System (INIS)

Orton, H.

2005-01-01

This presentation describes state of the art in power cable design, failure mechanisms and testing. It gives a history of cable usage and design of cables, describes different cable types, assessment of the condition of cables, aging and failures, testing and diagnostics

Applications of electromagnetic principles in the design and development of proximity wireless sensors

Science.gov (United States)

Alam, Md Nazmul

. Third, a new mathematical method is developed that can be used to determine the changes in the dielectric constant of a cable insulating material. By comparing the experimental JTFDR waveform signatures from a new and an aged cable, it is demonstrated that the change in the average dielectric constant of the insulation material can be estimated from the phase transfer functions obtained from the FFT of measured magnitude and phase responses. The experimental data obtained for two types of cables, XLPE and EPR show that the dielectric constant decreases with accelerated aging. Finally, JTFDR surface wave sensing method is developed and applied to determine the locations of aging related insulation damage in power cables. The comparative power spectral responses of conducted and non-intrusive surface wave JTFDR waveforms clearly show the resulting bandwidth reduction in the latter primarily because of the reflective nature of the coupling. It is demonstrated that with the help of a non-intrusive wave launcher and a 120 MHz Gaussian chirp waveform the location of aging related insulation damages can be detected. Experiments conducted show the cross-correlation peaks at subsequent aging intervals as the cable is aged inside a heat chamber.

Method discussion of the performance evaluation on nuclear plant cable

International Nuclear Information System (INIS)

Lu Yongfang; Zhong Weixia; Sun Jiansheng; Liu Jingping

2014-01-01

A stock cable, which is same as the nuclear plant cable in service, was treated by thermal aging. After that, the mechanical property, the flame retardant property, the anti-oxidation were measured, and relationships between them due to the thermal aging were established. By those analysis, evaluating the in-service cable performance in nuclear plant and calculating its remaining life. Furthermore, the feasibility of this method was disscussed. (authors)

Frequency domain reflectometry modeling for nondestructive evaluation of nuclear power plant cables

Science.gov (United States)

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

2018-04-01

Cable insulation polymers are among the more susceptible materials to age-related degradation within a nuclear power plant. This is recognized by both regulators and utilities, so all plants have developed cable aging management programs to detect damage before critical component failure in compliance with regulatory guidelines. Although a wide range of tools are available to evaluate cables and cable systems, cable aging management programs vary in how condition monitoring and nondestructive examinations are conducted as utilities search for the most reliable and cost-effective ways to assess cable system condition. Frequency domain reflectometry (FDR) is emerging as one valuable tool to locate and assess damaged portions of a cable system with minimal cost and only requires access in most cases to one of the cable terminal ends. Since laboratory studies to evaluate the use of FDR for inspection of aged cables can be expensive and data interpretation may be confounded by multiple factors which influence results, a model-based approach is desired to parametrically investigate the effect of insulation material damage in a controlled manner. This work describes development of a physics-based FDR model which uses finite element simulations of cable segments in conjunction with cascaded circuit element simulations to efficiently study a cable system. One or more segments of the cable system model have altered physical or electrical properties which represent the degree of damage and the location of the damage in the system. This circuit model is then subjected to a simulated FDR examination. The modeling approach is verified using several experimental cases and by comparing it to a commercial simulator suitable for simulation of some cable configurations. The model is used to examine a broad range of parameters including defect length, defect profile, degree of degradation, number and location of defects, FDR bandwidth, and addition of impedance-matched extensions to

Development of low-smoke, flame-retarding cables

International Nuclear Information System (INIS)

Kato, H.; Kanemitsuya, K.; Furukawa, K.; Mio, K.

1983-01-01

A great deal of attention has been given to the potential fire hazard of combustion gases from organic materials. Although cable industries have developed flame-retarding organic materials for the insulation and jacketing of wires and cables, there was insufficient prevention of toxic gas formation during combustion. To cope with these problems associated with conventional PVC cables, the authors have directed to develop low-smoke, flame-retarding plasticized PVC formulations retaining the original mechanical, electrical and aging properties. A series of basic investigations on smoke suppression followed by an evaluation on practical cables could indicate some effective means to end these problems. This paper describes the results and discussion on smoke suppressing study of plasticized PVC as well as behavior and characteristics of the low-smoke, flame-retarding PVC wires and cables using these materials. (author)

The correlation between elongation at break and thermal decomposition of aged EPDM cable polymer

Science.gov (United States)

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

2017-03-01

The effect of simultaneous thermal and gamma irradiation ageing on the mechanical and physicochemical properties of industrial EPDM was investigated. Accelerated ageing, covering a wide range of dose rates, doses and temperatures, was preformed in stagnant air on EPDM polymer samples extracted from the cables in use in the Belgian nuclear power plants. The mechanical properties, ultimate tensile stress and elongation at break, are found to exhibit the strong dependence on the dose, ageing temperature and dose rate. The thermal decomposition of aged polymer is observed to be the dose dependent when thermogravimetry test is performed under air atmosphere. No dose dependence is observed when thermal decomposition is performed under nitrogen atmosphere. The thermal decomposition rates are found to fully mimic the reduction of elongation at break for all dose rates and ageing temperatures. This effect is argued to be the result of thermal and radiation mediated oxidation degradation process.

AN EVALUATION OF CONDITION MONITORING TECHNIQUES FOR LOW-VOLTAGE ELECTRIC CABLES

International Nuclear Information System (INIS)

LOFARO, R.J.; GROVE, E.; SOO, P.

2000-01-01

Aging of systems and components in nuclear power plants is a well known occurrence that must be managed to ensure the continued safe operation of these plants. Much of the degradation due to aging is controlled through periodic maintenance and/or component replacement. However, there are components that do not receive periodic maintenance or monitoring once they are installed; electric cables are such a component. To provide a means of monitoring the condition of electric cables, research is ongoing to evaluate promising condition monitoring (CM) techniques that can be used in situ to monitor cable condition and predict remaining life. While several techniques are promising, each has limitations that must be considered in its application. This paper discusses the theory behind several of the promising cable CM techniques being studied, along with their effectiveness for monitoring aging degradation in typical cable insulation materials, such as cross-linked polyethylene and ethylene propylene rubber. Successes and limitations of each technique are also presented

Light Water Reactor Sustainability (LWRS) Program – Non-Destructive Evaluation (NDE) R&D Roadmap for Determining Remaining Useful Life of Aging Cables in Nuclear Power Plants

Energy Technology Data Exchange (ETDEWEB)

Simmons, K.L.; Ramuhali, P.; Brenchley, D.L.; Coble, J.B.; Hashemian, H.M.; Konnick, R.; Ray, S.

2012-09-01

Executive Summary [partial] The purpose of the non-destructive evaluation (NDE) R&D Roadmap for Cables is to support the Materials Aging and Degradation (MAaD) R&D pathway. A workshop was held to gather subject matter experts to develop the NDE R&D Roadmap for Cables. The focus of the workshop was to identify the technical gaps in detecting aging cables and predicting their remaining life expectancy. The workshop was held in Knoxville, Tennessee, on July 30, 2012, at Analysis and Measurement Services Corporation (AMS) headquarters. The workshop was attended by 30 experts in materials, electrical engineering, and NDE instrumentation development from the U.S. Nuclear Regulatory Commission (NRC), U.S. Department of Energy (DOE) National Laboratories (Oak Ridge National Laboratory, Pacific Northwest National Laboratory, Argonne National Laboratory, and Idaho National Engineering Laboratory), universities, commercial NDE service vendors and cable manufacturers, and the Electric Power Research Institute (EPRI).

Physical degradation assessment of generator station cables

International Nuclear Information System (INIS)

Stonkus, D.J.

1988-01-01

Preliminary studies of fossil-fired and nuclear generator station cables indicate that the low voltage PVC insulated cables are in relatively good condition. The insulation is flexible and in the case of nuclear cables can withstand a design basis event after nearly 15 years of service. Cables insulated with styrene butadiene rubber have been found embrittled and cables insulated with SBR should be closely inspected in any plant assurance program. Thermal analysis using oxidative induction technique shows promise to indicate cable insulation degradation. Long term reliability assurance and plant life extension studies are being actively pursued at Ontario Hydro. A major study is currently underway to extend the life of the oldest operating fossil-fuel station, the 8-unit, 2400 MW Lakeview TGS in operation since the 1960s. Plant life assurance programs have been initiated at the 2000 MW Lambton TGS in operation since 1969, and for the oldest operating nuclear plant, Pickering NGS A in operation since the early 1970s. As cables are considered one of the critical components in a generator station due to the extreme difficulty and cost of cable replacement, test programs have been initiated to evaluate the physical degradation of the cables and relate the results to electrical diagnostic tests and to chemical changes. The decommissioning of two small nuclear stations, the 20 MW Nuclear Power Demonstration (NPD) and the 200 MW Douglas Point NGS, which were placed in service in 1962 and 1967 respectively, will provide an opportunity to perform destructive electrical and physical evaluation on field aged cables

Status Report and Research Plan for Cables Harvested from Crystal River Unit 3 Nuclear Generating Plant

Energy Technology Data Exchange (ETDEWEB)

Fifield, Leonard S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2016-09-20

Harvested cables from operating or decommissioned nuclear power plants present an important opportunity to validate models, understanding material aging behavior, and validate characterization techniques. Crystal River Unit 3 Nuclear Generating Plant is a pressurized water reactor that was licensed to operate from 1976 to 2013. Cable segments were harvested and made available to the Light Water Reactor Sustainability research program through the Electric Power Research Institute. Information on the locations and circuits within the reactor from whence the cable segments came, cable construction, sourcing and installation information, and photographs of the cable locations prior to harvesting were provided. The cable variations provided represent six of the ten most common cable insulations in the nuclear industry and experienced service usage for periods from 15 to 42 years. Subsequently, these cables constitute a valuable asset for research to understand aging behavior and measurement of nuclear cables. Received cables harvested from Crystal River Unit 3 Nuclear Generating Plant consist of low voltage, insulated conductor surrounded by jackets in lengths from 24 to 100 feet each. Cable materials will primarily be used to investigate aging under simultaneous thermal and gamma radiation exposure. Each cable insulation and jacket material will be characterized in its as-received condition, including determination of the temperatures associated with endothermic transitions in the material using differential scanning calorimetry and dynamic mechanical analysis. Temperatures for additional thermal exposure aging will be selected following the thermal analysis to avoid transitions in accelerated laboratory aging that do not occur in field conditions. Aging temperatures above thermal transitions may also be targeted to investigate the potential for artifacts in lifetime prediction from rapid accelerated aging. Total gamma doses and dose rates targeted for each material

Ethylene propylene cable degradation during LOCA research tests: tensile properties at the completion of accelerated aging

International Nuclear Information System (INIS)

Bustard, L.D.

1982-05-01

Six ethylene-propylene rubber (EPR) insulation materials were aged at elevated temperature and radiation stress exposures common in cable LOCA qualification tests. Material samples were subjected to various simultaneous and sequential aging simulations in preparation for accident environmental exposures. Tensile properties subsequent to the aging exposure sequences are reported. The tensile properties of some, but not all, specimens were sensitive to the order of radiation and elevated temperature stress exposure. Other specimens showed more severe degradation when simultaneously exposed to radiation and elevated temperature as opposed to the sequential exposure to the same stresses. Results illustrate the difficulty in defining a single test procedure for nuclear safety-related qualification of EPR elastomers. A common worst-case sequential aging sequence could not be identified

Application of optical diagnosis to aged low-voltage cable insulation in nuclear plants

International Nuclear Information System (INIS)

Katagiri, Junichi; Takezawa, Yoshitaka; Shouji, Hiroshi

2008-01-01

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 (ΔA R ), 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 ΔA R 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 ΔA R 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. (author)

Cable line engineering

International Nuclear Information System (INIS)

Jang, Hak Sin; Kim, Sin Yeong

1998-02-01

This book is about cable line engineering. It is comprised of nine chapters, which deals with summary of cable communication such as way, process of cable communication and optical communication, Line constant of transmission on primary constant, reflection and crosstalk, communication cable line of types like flat cable, coaxial cable and loaded cable, Install of communication line with types and facility of aerial line, construction method of communication line facility, Measurement of communication line, Carrier communication of summary, PCM communication with Introduction, regeneration relay system sampling and quantization and Electric communication service and general information network with mobile communication technique and satellite communication system.

Fiscal 1999 research result report on energy and environment technology demonstration research support project (International joint demonstration research project). Improvement of long-distant power transmission efficiency and reliability, and its environmental impact assessment; 1999 nendo chokyori soden hoshiki ni kansuru soden koritsu to soden shinraido no kojo oyobi kankyo eno eikyo hyoka seika hokokusho

Energy Technology Data Exchange (ETDEWEB)

NONE

2000-03-01

Japan-Russia international joint research was made on overhead ultrahigh-voltage DC power transmission lines for transmission loss reduction and reliability improvement, and an optimum international power supply cable system, considering energy saving and environment conservation. Using the European-Russian DC power transmission line of {+-}500kV and 4GW as a model, comparison was made between a model using Russian round strands and glass insulators and a model using Japanese low-loss wires and insulators. As for improvement of the reliability in cold districts, Russian design techniques for tower structure and ice loading were reasonable to counteract galloping oscillation and ice load. In evaluation and selection of optimum underground and marine cables, study was made on cable specifications using the Turkey-Russia power transmission route as a model. The environmental assessment result of these cables showed that XLPE cable under development is optimum. (NEDO)

Nuclear grade cable thermal life model by time temperature superposition algorithm based on Matlab GUI

International Nuclear Information System (INIS)

Lu Yanyun; Gu Shenjie; Lou Tianyang

2014-01-01

Background: As nuclear grade cable must endure harsh environment within design life, it is critical to predict cable thermal life accurately owing to thermal aging, which is one of dominant factors of aging mechanism. Purpose: Using time temperature superposition (TTS) method, the aim is to construct nuclear grade cable thermal life model, predict cable residual life and develop life model interactive interface under Matlab GUI. Methods: According to TTS, nuclear grade cable thermal life model can be constructed by shifting data groups at various temperatures to preset reference temperature with translation factor which is determined by non linear programming optimization. Interactive interface of cable thermal life model developed under Matlab GUI consists of superposition mode and standard mode which include features such as optimization of translation factor, calculation of activation energy, construction of thermal aging curve and analysis of aging mechanism., Results: With calculation result comparison between superposition and standard method, the result with TTS has better accuracy than that with standard method. Furthermore, confidence level of nuclear grade cable thermal life with TTS is higher than that with standard method. Conclusion: The results show that TTS methodology is applicable to thermal life prediction of nuclear grade cable. Interactive Interface under Matlab GUI achieves anticipated functionalities. (authors)

Partial discharge testing of in-situ power cable accessories

Energy Technology Data Exchange (ETDEWEB)

Orban, H. E.

2002-07-01

An overview of commercially available diagnostic methods for in-situ power cable accessories is given and relevant field experiences with these diagnostics are described. The discussion includes both PILC and polymeric insulated cables. Two major types of degradation are most frequently involved in cable systems. One is an overall condition caused by chemical aging and /or water treeing. Diagnostics for this type of aging include dissipation factor (loss angle), harmonic analysis, return voltage, isothermal relaxation current, dielectric response, or dc leakage current. The second type of degradation is discrete or incremental; condition assessment utilizes dissipation factor measurements or partial discharge (PD) level measurements. The focus in this paper is on PD diagnostics, especially off-line methods such as the 60 Hz test, the combined AC and VLF diagnostic, and the oscillating wave test system test. Among on-line diagnostics, ultrasonic detection of partial discharge and measurement of partial discharge by installing direct, capacitive or inductive couplers near cable accessories, are described. Overall, partial discharge detection and location in cable accessories is considered inadequate, since interpretation of results is difficult due to the number of variables involved. 28 refs., 1 tab.

Superconducting ac cable

Science.gov (United States)

Schmidt, F.

1980-11-01

The components of a superconducting 110 kV ac cable for power ratings or = 2000 MVA were developed. The cable design is of the semiflexible type, with a rigid cryogenic envelope containing a flexible hollow coaxial cable core. The cable core consists of spirally wound Nb-A1 composite wires electrically insulated by high pressure polyethylene tape wrappings. A 35 m long single phase test cable with full load terminals rated at 110 kV and 10 kA was constructed and successfully tested. The results obtained prove the technical feasibility and capability of this cable design.

Superconducting ac cable

International Nuclear Information System (INIS)

Schmidt, F.

1980-01-01

The components of a superconducting 110 kV ac cable for power ratings >= 2000 MVA have been developed. The cable design especially considered was of the semiflexible type, with a rigid cryogenic envelope and flexible hollow coaxial cable cores pulled into the former. The cable core consists of spirally wound Nb-Al composite wires and a HDPE-tape wrapped electrical insulation. A 35 m long single phase test cable with full load terminations for 110 kV and 10 kA was constructed and successfully tested. The results obtained prove the technical feasibility and capability of our cable design. (orig.) [de

Effects of thermal ageing and gamma radiations on ethylene-propylene based insulator of electric cables

International Nuclear Information System (INIS)

Baccaro, S.; D'Atanasio, P.

1986-01-01

This paper describes the effects of gamma radiation and thermal aging on cable insulator. The elastic properties degrade rapidly as the absorbed dose increases: the percent elongation at break attains nearly 100% value at 0.5 MGy absorbed dose. The gases evolved during the irradiation are mainly H 2 and CO 2 ; CO, CH 4 and C 2 H 6 are present in much lower concentrations. The damage undergone depends strongly on sequential radiation and thermal aging; the analysis of accelerated life test data by means of the Arrhenius model gave (1.23+-0.25) eV for the activation energy, about 1 eV higher than the values reported in the literature

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.

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

Science.gov (United States)

Xie, Xu; Li, Xiaozhang; Shen, Yonggang

2014-06-23

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.

Applicability of qualification testing of electric cable to life extension

International Nuclear Information System (INIS)

Reynolds, A.B.

1988-01-01

The methods for qualification testing of electric cable for nuclear power plants followed by U.S. cable manufacturers and endorsed by the U.S. Nuclear Regulatory Commission (NRC) involve irradiation aging at high dose rates at room temperature and accident aging in steam without the pressure of air. Testing is done sequentially. The research data which led to some concerns have been reviewed, and some conclusions regarding these concerns are suggested

Assessment of the burning behavior of protected and unprotected cables and cable trays in nuclear installations using small- and large-scale experiments

Energy Technology Data Exchange (ETDEWEB)

Siemon, Matthias; Riese, Olaf; Zehfuss, Jochen [Technische Univ. Braunschweig (Germany). Inst. fuer Baustoffe, Massivbau und Brandschutz (iBMB)

2015-12-15

Electric installations and cables are a main fire risk source in industrial buildings and power plants. In general, cables and cable systems are associated with flash-over phenomena due to pyrolysis of fuel gases induced by the heat of an adjacent fire, fire spread along cable trays affecting additional areas besides the fire origin, being an ignition source due to malfunction. If burning, cables can emit large amounts of smoke and toxic products affecting occupants as well as the long-term functionality of structure and installations. Paying attention to these risks has led to the development of fire retardant non-corrosive (non-halogenated) cables which are qualified to reduce the individual or all of the risks mentioned. For existing installations in industrial buildings and power plants with halogenated cables, different protection measures are available and widely applied retroactively. Important protective measures are intumescent or ablative coatings, cable casings and bindings. For qualification of the effects of the protection measures, small-scale tests investigating a single cable specimen as well as large-scale cable tray test setups have been developed and carried out in the last 20 years at iBMB. In this paper, these test results are analysed regarding their effects on the heat release, ignition time and fire spread over cable trays. Furthermore, national and international research projects have investigated the burning behaviour of different cable types, tray installations, tray loading and spacing and ventilation conditions. As a conclusion, the main outcomes of past researches are summarized. Influence factors (e.g. pre-heating due to high power utilization, influence of cable aging) which have not been accounted for in detail are emphasized. The modelling of unprotected cables has been internationally studied in recent years. For future applications, the question of applicability of recently developed sub-models on the fire behaviour of protected

Static and Dynamic Mechanical Properties of Long-Span Cable-Stayed Bridges Using CFRP Cables

Directory of Open Access Journals (Sweden)

Mei Kuihua

2017-01-01

Full Text Available The elastic modulus and deadweight of carbon fiber-reinforced polymer (CFRP cables are different from those of steel cables. Thus, the static and dynamic behaviors of cable-stayed bridges using CFRP cables are different from those of cable-stayed bridges using steel cables. The static and dynamic performances of the two kinds of bridges with a span of 1000 m were studied using the numerical method. The effects of geometric nonlinear factors on static performance of the two kinds of cable-stayed bridges were analyzed. The live load effects and temperature effects of the two cable-stayed bridges were also analyzed. The influences of design parameters, including different structural systems, the numbers of auxiliary piers, and the space arrangement types of cable, on the dynamic performance of the cable-stayed bridge using CFRP cables were also studied. Results demonstrate that sag effect of the CFRP cable is much smaller than that of steel cable. The temperature effects of CFRP cable-stayed bridge are less than those of steel cable-stayed bridge. The vertical bending natural vibration frequency of the CFRP cable-stayed bridge is generally lower than that of steel cable-stayed bridge, whereas the torsional natural vibration frequency of the former is higher than that of the latter.

On the Minimum Cable Tensions for the Cable-Based Parallel Robots

Directory of Open Access Journals (Sweden)

Peng Liu

2014-01-01

Full Text Available This paper investigates the minimum cable tension distributions in the workspace for cable-based parallel robots to find out more information on the stability. First, the kinematic model of a cable-based parallel robot is derived based on the wrench matrix. Then, a noniterative polynomial-based optimization algorithm with the proper optimal objective function is presented based on the convex optimization theory, in which the minimum cable tension at any pose is determined. Additionally, three performance indices are proposed to show the distributions of the minimum cable tensions in a specified region of the workspace. An important thing is that the three performance indices can be used to evaluate the stability of the cable-based parallel robots. Furthermore, a new workspace, the Specified Minimum Cable Tension Workspace (SMCTW, is introduced, within which all the minimum tensions exceed a specified value, therefore meeting the specified stability requirement. Finally, a camera robot parallel driven by four cables for aerial panoramic photographing is selected to illustrate the distributions of the minimum cable tensions in the workspace and the relationship between the three performance indices and the stability.

Universal Cable Brackets

Science.gov (United States)

Vanvalkenburgh, C.

1985-01-01

Concept allows routing easily changed. No custom hardware required in concept. Instead, standard brackets cut to length and installed at selected locations along cable route. If cable route is changed, brackets simply moved to new locations. Concept for "universal" cable brackets make it easy to route electrical cable around and through virtually any structure.

Cable fire tests in France

International Nuclear Information System (INIS)

Kaercher, M.

2000-01-01

Modifications are being carried out in all French nuclear power plants to improve fire safety. These modifications are based on a three level defense in depth concept: fire preventing, fire containing and fire controlling. Fire containing requires many modifications such as protection of cable races and assessment of fire propagation which both need R and D development. On one hand, cable wraps made with mineral wool were tested in all configurations including effect of aging, overheating and fire and qualified for the use as protection from common failure modes. On the other hand, cables races in scale one were subject to gas burner or solvent pool fire to simulate ignition and fire propagation between trays and flash over situations. These tests have been performed under several typical lay out conditions. The results of the tests can be used as input data in computer modelling for validation of fire protection measures. (orig.) [de

Wind-induced cable vibrations and countermeasures of cables of PC cable-stayed bridge. PC syachokyo keburu no kaze ni yoru shindo to sono taisaku

Energy Technology Data Exchange (ETDEWEB)

Yoneda, M. (Kawada Industries Inc., Tokyo (Japan))

1994-05-01

In recent years, long span of cable-stayed bridges is remarkable. The wind-induced cable vibration called as line vibration and wake galloping was given as an important problem not only in the steel cable-stayed bridges but also in the PC cable-stayed bridges. The technical engineers in design of the cable-stayed bridges have many times to confront the problems on the vibration control of cables, it is considered that sufficient understand of the wind-induced vibration and countermeasures for cables of the PC cable-stayed bridges is necessary. Many reports on the countermeasure examples and trend of vibration control centred on cables of the cable-stayed bridges have been published. In this paper, the wind-induced vibration of cables in the cable-stayed bridges was reviewed, the examples of countermeasures of vibration control on cables in the PC cable-stayed bridges was mainly introduced. The remaining tasks and future prospects on vibration control of the PC cable-stayed bridges were described. 14 refs., 13 figs., 4 tabs.

Study on condition monitoring techniques for low voltage electrical cables in nuclear power plants

International Nuclear Information System (INIS)

Hirao, Hideo; Sakai, Takeshi; Kajimura, Yuusaku

2017-01-01

Low voltage electrical cables installed in nuclear power plants are required to maintain its function in a design basis accident environment and they are qualified to that environment. The cables degrade also in normal operating conditions due to ageing and they must maintain integrity until the end of their qualified life. Demands for the condition monitoring technique for low voltage electrical cables have therefore been increasing as nuclear power plants operate longer. A single perfect method for this purpose is not available yet, but the possibility to use two different types of methods which can complement with each other has been examined. The combination of Fourier Transform Infrared Spectroscopy (FT-IR) and Indenter Modulus (IM) method was found highly effective. FT-IR is a method that determines chemical properties (changes in molecular bindings) of cables by using infrared rays, while IM is a method that determines mechanical properties (changes in hardness) of cables by indenters. Both methods are non-destructive and can be applied in-situ to the same material. Reliability of the evaluation can be assured by applying two different types of measurement principles that complement with each other. In this study, various cable samples with different kinds of insulation material (cross-linked polyethylene, ethylene propylene rubber, silicone rubber etc.) were aged with a special accelerated ageing technique which applies simultaneous thermal and radiation ageing to simulate ageing phenomena in a more realistic manner, and the degree of ageing was evaluated with FT-IR and IM. The evaluation result shows good correlation with ageing time and other ageing properties for most material types and the effectiveness of these methods were demonstrated. (author)

Progress on qualification testing methodology study of electric cables

International Nuclear Information System (INIS)

Yoshida, K.; Seguchi, T.; Okada, S.; Ito, M.; Kusama, Y.; Yagi, T.; Yoshikawa, M.

1983-01-01

Many instrumental, control and power cables are installed in nuclear power plants, and these cables contain a large amount of organic polymers as insulating and jacketing materials. They are exposed to radiation at high dose rate, steam at high temperature and chemical (or water) spray simultaneously when a LOCA occurs. Under such conditions, the polymers tend to lose their original properties. For reactor safety, the cables should be functional even if they are subjected to a loss-of-coolant accident (LOCA) at the end of their intended service life. In Japan, cable manufacturers qualify their cables according to the proposed test standard issued from IEEJ in 1982, but the standard still has many unsolved problems or uncertainties which have been dealt with tentatively through the manufacturer-user's agreement. The objectives of this research are to study the methodologies for qualification testing of electric wires and cables, and to provide the improved technical bases for modification of the standard. Research activities are divided into the Accident (LOCA) Testing Methodology and the Accelerated Aging Methodology

Rotator cuff tendon connections with the rotator cable.

Science.gov (United States)

Rahu, Madis; Kolts, Ivo; Põldoja, Elle; Kask, Kristo

2017-07-01

The literature currently contains no descriptions of the rotator cuff tendons, which also describes in relation to the presence and characteristics of the rotator cable (anatomically known as the ligamentum semicirculare humeri). The aim of the current study was to elucidate the detailed anatomy of the rotator cuff tendons in association with the rotator cable. Anatomic dissection was performed on 21 fresh-frozen shoulder specimens with an average age of 68 years. The rotator cuff tendons were dissected from each other and from the glenohumeral joint capsule, and the superior glenohumeral, coracohumeral, coracoglenoidal and semicircular (rotator cable) ligaments were dissected. Dissection was performed layer by layer and from the bursal side to the joint. All ligaments and tendons were dissected in fine detail. The rotator cable was found in all specimens. It was tightly connected to the supraspinatus (SSP) tendon, which was partly covered by the infraspinatus (ISP) tendon. The posterior insertion area of the rotator cable was located in the region between the middle and inferior facets of the greater tubercle of the humerus insertion areas for the teres minor (TM), and ISP tendons were also present and fibres from the SSP extended through the rotator cable to those areas. The connection between the rotator cable and rotator cuff tendons is tight and confirms the suspension bridge theory for rotator cuff tears in most areas between the SSP tendons and rotator cable. In its posterior insertion area, the rotator cable is a connecting structure between the TM, ISP and SSP tendons. These findings might explain why some patients with relatively large rotator cuff tears can maintain seamless shoulder function.

The correlation between elongation at break and thermal decomposition of aged EPDM cable polymer

International Nuclear Information System (INIS)

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

2017-01-01

The effect of simultaneous thermal and gamma irradiation ageing on the mechanical and physicochemical properties of industrial EPDM was investigated. Accelerated ageing, covering a wide range of dose rates, doses and temperatures, was preformed in stagnant air on EPDM polymer samples extracted from the cables in use in the Belgian nuclear power plants. The mechanical properties, ultimate tensile stress and elongation at break, are found to exhibit the strong dependence on the dose, ageing temperature and dose rate. The thermal decomposition of aged polymer is observed to be the dose dependent when thermogravimetry test is performed under air atmosphere. No dose dependence is observed when thermal decomposition is performed under nitrogen atmosphere. The thermal decomposition rates are found to fully mimic the reduction of elongation at break for all dose rates and ageing temperatures. This effect is argued to be the result of thermal and radiation mediated oxidation degradation process. - Highlights: • EPDM is aged in a wide range of dose rates and temperatures. • Tensile and thermogravimetry test were performed. • Mechanical parameters are strongly affected by irradiation dose and temperature. • Direct link between the mechanical and physicochemical properties is provided. • Thermal and radiation mediated oxidation degradation is considered to be important.

Comparison study of cable geometries and superconducting tape layouts for high-temperature superconductor cables

Science.gov (United States)

Ta, Wurui; Shao, Tianchong; Gao, Yuanwen

2018-04-01

High-temperature superconductor (HTS) rare-earth-barium-copper-oxide (REBCO) tapes are very promising for use in high-current cables. The cable geometry and the layout of the superconducting tapes are directly related to the performance of the HTS cable. In this paper, we use numerical methods to perform a comparison study of multiple-stage twisted stacked-tape cable (TSTC) conductors to find better cable structures that can both improve the critical current and minimize the alternating current (AC) losses of the cable. The sub-cable geometry is designed to have a stair-step shape. Three superconducting tape layouts are chosen and their transport performance and AC losses are evaluated. The magnetic field and current density profiles of the cables are obtained. The results show that arrangement of the superconducting tapes from the interior towards the exterior of the cable based on their critical current values in descending order can enhance the cable's transport capacity while significantly reducing the AC losses. These results imply that cable transport capacity improvements can be achieved by arranging the superconducting tapes in a manner consistent with the electromagnetic field distribution. Through comparison of the critical currents and AC losses of four types of HTS cables, we determine the best structural choice among these cables.

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...... to quantify the different structural configurations and allows a preliminary optimization of the main structure.Included are the most recent advances in structural design, corrosion protection of cables, aerodynamic safety, and erection procedures....

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

DEFF Research Database (Denmark)

Holbøll, Joachim; Henriksen, Mogens; Hjerrild, Jesper

2000-01-01

and temperatures were applied in the 20 - 80°C range with gradients across the insulation of up to 15°C. In this paper, the observed charge phenomena in the bulk and at the interfaces are related to the external conditions, in particular to the temperature gradient. The measured space charge distributions...

30 CFR 77.601 - Trailing cables or portable cables; temporary splices.

Science.gov (United States)

2010-07-01

... LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS, SURFACE COAL MINES AND SURFACE WORK AREAS OF UNDERGROUND COAL MINES Trailing Cables § 77.601 Trailing cables or portable cables; temporary... or splices that heat or spark under load shall not be used. ...

Characterization of in-containment cables for nuclear plant life extension

International Nuclear Information System (INIS)

DuCharme, A.R.; Bustard, L.D.

1988-01-01

Electrical cable is made by a large number of manufacturers and used for a variety of applications in nuclear plants. cables have been identified in the Monticello and Surry Pilot Plant life extension studies and the NRC Nuclear Plant Aging Research Program as components important to the economic and safety aspects of life extension. Currently, fitness for service is largely determined by preoperational testing. The US Department of Energy is supporting work at Sandia National Laboratories to assess the technical basis for the life extension of cables found inside containment at US nuclear plants. The work is being performed in coordination with the Nuclear Management and Resource Council's (NUMARC) NUPLEX Working Group. The initial task of this effort is to characterize the design attributes of in-containment cables. This has been completed via development of a data base depicting the manufacturer, type, material composition, use, qualification, and relative popularity of cables installed in containment. Other ongoing work is focused on a review of cable operational experience and assessment of the issues affecting cable life extension. In the long term, the work aims to identify the technical criteria and life extension strategies needed to support continued cable qualification by nuclear plant owner/operators. 7 refs., 4 tabs

Parametrically excited oscillation of stay cable and its control in cable-stayed bridges.

Science.gov (United States)

Sun, Bing-nan; Wang, Zhi-gang; Ko, J M; Ni, Y Q

2003-01-01

This paper presents a nonlinear dynamic model for simulation and analysis of a kind of parametrically excited vibration of stay cable caused by support motion in cable-stayed bridges. The sag, inclination angle of the stay cable are considered in the model, based on which, the oscillation mechanism and dynamic response characteristics of this kind of vibration are analyzed through numerical calculation. It is noted that parametrically excited oscillation of a stay cable with certain sag, inclination angle and initial static tension force may occur in cable-stayed bridges due to deck vibration under the condition that the natural frequency of a cable approaches to about half of the first model frequency of the bridge deck system. A new vibration control system installed on the cable anchorage is proposed as a possible damping system to suppress the cable parametric oscillation. The numerical calculation results showed that with the use of this damping system, the cable oscillation due to the vibration of the deck and/or towers will be considerably reduced.

Magnet cable manufacturing

International Nuclear Information System (INIS)

Royet, J.

1985-07-01

The superconducting magnets used in the construction of particle accelerators are mostly built from flat, multistrand cables with rectangular or keystoned cross sections. The superconducting strands are mostly circular but a design of a cable made of preflattened wires was proposed a few years ago under the name of Berkeley flat; such cable shows some interesting characteristics. Another design consists of a few smaller precabled wires (e.g. 6 around 1). This configuration allows smaller filaments and a better transposition of the current elements. The Superconducting Super Collider project involves the largest amount of superconducting cable ever envisaged for a single machine. Furthermore, the design calls for exceptional accuracy and improved characteristics of the cable. A part of the SSC research and development program is focused on these important questions. In this paper we emphasize the difference between the conventional cabling and wires with superconducting. A new concept for the tooling will be introduced as well as the necessary characteristics of a specialized cabler. 5 figs

Cable strengthened arches

NARCIS (Netherlands)

Kamerling, M.W.

2013-01-01

The structural efficiency of arches, subjected to several variable loads, can be increased by strengthening these arches with cables. For these structures it can be necessary, especially in case the permanent load is small, to post-tension the cables to avoid any compression acting on the cables. A

A new multiconstraint method for determining the optimal cable stresses in cable-stayed bridges.

Science.gov (United States)

Asgari, B; Osman, S A; Adnan, A

2014-01-01

Cable-stayed bridges are one of the most popular types of long-span bridges. The structural behaviour of cable-stayed bridges is sensitive to the load distribution between the girder, pylons, and cables. The determination of pretensioning cable stresses is critical in the cable-stayed bridge design procedure. By finding the optimum stresses in cables, the load and moment distribution of the bridge can be improved. In recent years, different research works have studied iterative and modern methods to find optimum stresses of cables. However, most of the proposed methods have limitations in optimising the structural performance of cable-stayed bridges. This paper presents a multiconstraint optimisation method to specify the optimum cable forces in cable-stayed bridges. The proposed optimisation method produces less bending moments and stresses in the bridge members and requires shorter simulation time than other proposed methods. The results of comparative study show that the proposed method is more successful in restricting the deck and pylon displacements and providing uniform deck moment distribution than unit load method (ULM). The final design of cable-stayed bridges can be optimised considerably through proposed multiconstraint optimisation method.

Nonlinear Analysis of Cable Vibration of a Multispan Cable-Stayed Bridge under Transverse Excitation

Directory of Open Access Journals (Sweden)

Kun Lin

2014-01-01

Full Text Available 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 results of MECS model analysis show that the main tower in the multispan cable-stayed bridge is prone to the transverse vibration, and the local vibration of cables only has a little impact on the frequency values of the global modes. The results of simplified model analysis show that the energy can be transformed between the modes of the beam and cable when the nature frequencies of them are very close. On the other hand, with the transverse excitation changing, the cable can exhibit richer quasi-periodic or chaotic motions due to the nonlinear terms caused by the coupled mode between the beam and cable.

A New Multiconstraint Method for Determining the Optimal Cable Stresses in Cable-Stayed Bridges

Directory of Open Access Journals (Sweden)

B. Asgari

2014-01-01

Full Text Available Cable-stayed bridges are one of the most popular types of long-span bridges. The structural behaviour of cable-stayed bridges is sensitive to the load distribution between the girder, pylons, and cables. The determination of pretensioning cable stresses is critical in the cable-stayed bridge design procedure. By finding the optimum stresses in cables, the load and moment distribution of the bridge can be improved. In recent years, different research works have studied iterative and modern methods to find optimum stresses of cables. However, most of the proposed methods have limitations in optimising the structural performance of cable-stayed bridges. This paper presents a multiconstraint optimisation method to specify the optimum cable forces in cable-stayed bridges. The proposed optimisation method produces less bending moments and stresses in the bridge members and requires shorter simulation time than other proposed methods. The results of comparative study show that the proposed method is more successful in restricting the deck and pylon displacements and providing uniform deck moment distribution than unit load method (ULM. The final design of cable-stayed bridges can be optimised considerably through proposed multiconstraint optimisation method.

Sizewell 'B' cable installation

International Nuclear Information System (INIS)

Gemmell, D.R.

1992-01-01

N G Bailey and Co. Ltd., UK were awarded the contract for the procurement, manufacture, works testing, works finishing, supply, delivery, off-loading, storage, installation, site finishing, preservation, setting to work and site testing of the following; the main cable installation throughout the Station including the addition of the Radioactive Waste Building, earthing and lightning protection installation, cable supporting steelwork and carriers and glanding and termination of cables. The cabling installation comprises power distribution, control and instrumentation cabling including all the associated cabling accessories, terminal boxes and similar components. The way that the contract was set-up, awarded and is now being carried out is described. Planning and industrial relations have been key features of the contract. (Author)

Simulation of the cabling process for Rutherford cables: An advanced finite element model

Science.gov (United States)

Cabanes, J.; Garlasche, M.; Bordini, B.; Dallocchio, A.

2016-12-01

In all existing large particle accelerators (Tevatron, HERA, RHIC, LHC) the main superconducting magnets are based on Rutherford cables, which are characterized by having: strands fully transposed with respect to the magnetic field, a significant compaction that assures a large engineering critical current density and a geometry that allows efficient winding of the coils. The Nb3Sn magnets developed in the framework of the HL-LHC project for improving the luminosity of the Large Hadron Collider (LHC) are also based on Rutherford cables. Due to the characteristics of Nb3Sn wires, the cabling process has become a crucial step in the magnet manufacturing. During cabling the wires experience large plastic deformations that strongly modify the geometrical dimensions of the sub-elements constituting the superconducting strand. These deformations are particularly severe on the cable edges and can result in a significant reduction of the cable critical current as well as of the Residual Resistivity Ratio (RRR) of the stabilizing copper. In order to understand the main parameters that rule the cabling process and their impact on the cable performance, CERN has developed a 3D Finite Element (FE) model based on the LS-Dyna® software that simulates the whole cabling process. In the paper the model is presented together with a comparison between experimental and numerical results for a copper cable produced at CERN.

DC Cable for Railway

Science.gov (United States)

Tomita, Masaru

The development of a superconducting cable for railways has commenced, assuming that a DC transmission cable will be used for electric trains. The cable has been fabricated based on the results of current testing of a superconducting wire, and various evaluation tests have been performed to determine the characteristics of the cable. A superconducting transmission cable having zero electrical resistance and suitable for railway use is expected to enhance regeneration efficiency, reduce power losses, achieve load leveling and integration of sub-stations, and reduce rail potential.

Assessment and management of ageing of major nuclear power plant components important to safety: In-containment instrumentation and control cables. Volume I

International Nuclear Information System (INIS)

2000-12-01

and technical support organizations dealing with specific plant components addressed in the reports. The component addressed in the present report is the in-containment instrumentation and control (I and C) cables. The report presents, in two volumes, results of a Co-ordinated Research Project (CRP) on the Management of Ageing of In-containment Instrumentation and Control cables. Part I, Volume 1 presents information on current methods for assessing and managing ageing degradation of Instrumentation and Control cables in real NPP environments prepared by the CRP team. An important complement of this information is user perspectives on the application of these methods which are presented in Part II, Volume 1. Volume 2 contains annexes supporting the guidance of Volume 1 with more detailed information and examples provided by individual CRP participants. For a quick overview, readers should see Section 8 of Part I, Volume 1, which describes a systematic ageing management programme for Instrumentation and Control cables utilizing methods presented in the report; Section 9 of Part I, Volume 1, which presents CRP conclusions and recommendations; and Part II providing the application guidance from the user's perspective

Assessment and management of ageing of major nuclear power plant components important to safety: In-containment instrumentation and control cables. Volume II

International Nuclear Information System (INIS)

2000-12-01

and technical support organizations dealing with specific plant components addressed in the reports. The component addressed in the present report is the in-containment instrumentation and control (I and C) cables. The report presents, in two volumes, results of a Co-ordinated Research Project (CRP) on the Management of Ageing of In-containment Instrumentation and Control cables. Part I, Volume 1 presents information on current methods for assessing and managing ageing degradation of Instrumentation and Control cables in real NPP environments prepared by the CRP team. An important complement of this information is user perspectives on the application of these methods which are presented in Part II, Volume 1. Volume 2 contains annexes supporting the guidance of Volume 1 with more detailed information and examples provided by individual CRP participants. For a quick overview, readers should see Section 8 of Part I, Volume 1, which describes a systematic ageing management programme for Instrumentation and Control cables utilizing methods presented in the report; Section 9 of Part I, Volume 1, which presents CRP conclusions and recommendations; and Part II providing the application guidance from the user's perspective

New impetus to research. Annual report 1996; Ny giv i forskningen. Aarsberetning 1996

Energy Technology Data Exchange (ETDEWEB)

NONE

1997-12-01

The annual report from the Norwegian Research Institute for Electricity gives snapshots from the research and development activities at the institute. The activities are: Short-term hydro operation planning; information and communication systems; consumer market; detection and localization of lightning flashes; cooperation in railway power supply; interactive tool for mechanical design of overhead lines; selection and dimensioning of cable; direct heating of pipelines; condition monitoring of power lines; breakdown mechanisms in transformer insulation; maintenance system for the future; power supply in extreme climates; acoustic detection of internal partial discharges in cable terminations; diagnostic testing of circuit-breakers; production technologies for power electronics; XLPE covered conductors; multi-area power market simulator. 12 figs.

Cable laying methods in a multi-cable elevator system

Energy Technology Data Exchange (ETDEWEB)

Dvornikov, V.I.; Makhinyan, V.V.

1984-01-01

Based on the solution of differential equations describing the stress and deformation state of cables during rolling on the drum, a conclusion is made concerning a rational method for hanging cables with a free-spinning end.

High Temperature Superconducting Underground Cable

International Nuclear Information System (INIS)

Farrell, Roger A.

2010-01-01

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 worlds 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.

Application study on the first cable-stayed bridge with CFRP cables in China

Directory of Open Access Journals (Sweden)

Kuihua Mei

2015-08-01

Full Text Available In order to push forward the development of CFRP cable-stayed bridge and accumulate experiences, the study on the application of the first cable-stayed bridge with CFRP cables in China was carried out. The design essentials of main components of the bridge were introduced and its integral performances, including static properties, dynamic properties and seismic response were analyzed using finite element method. A new bond-type anchorage was developed and the processes of fabricating and installing CFRP cables were elaborated. Based on the results of construction simulation, a tension scheme for bridge was propound. During constructing, the stresses and displacement of girder and pylon, as well as the forces and stresses of cables, were tested. The results indicate that all sections of the bridge could meet the requirements of the ultimate bearing capacity and normal service; the performance of the anchorage is good and the stresses in each cable system are similar; the tested values accord well with the calculated values. Further, creep deformation of the resin in anchorages under service load is not obvious. All these results demonstrate that the first application of CFRP cables in the cable-stayed bridge in China is successful.

Cable support arrangements

International Nuclear Information System (INIS)

Pendleton, E.; Murray, A.

1983-01-01

A cable support arrangement extending from a refuelling level floor of a nuclear reactor to the inner shield of a double rotatable shield comprises a linearly extensible cable support and disciplining boom, reaching from the floor to the main shield, and a circumferentially extensible cable support and disciplining means running from the end of the boom to a fixed end on the inner shield. (author)

Switching Restrikes in HVAC Cable Lines and Hybrid HVAC Cable/OHL Lines

DEFF Research Database (Denmark)

da Silva, Filipe Miguel Faria; Bak, Claus Leth; Balle Holst, Per

2011-01-01

The disconnection of HV underground cables may, if unsuccessful, originate a restrike in the circuit breaker, leading to high overvoltages, and potentially damaging the cable and near equipment. Due to the cable high capacitance and low resistance the voltage damping is slow, resulting, half a cy...

30 CFR 7.407 - Test for flame resistance of electric cables and cable splices.

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Test for flame resistance of electric cables... Electric Cables, Signaling Cables, and Cable Splice Kits § 7.407 Test for flame resistance of electric... material and 21/2 inches of conductor insulation. The type, amperage, voltage rating, and construction of...

Analysis to long-term stability of solar cables; Untersuchungen zur Langzeitstabilitaet von Solarleitungen

Energy Technology Data Exchange (ETDEWEB)

Funtan, P.

2005-07-01

For the moment it is not possible to say anything about the long-term stability of solar cables. Own experiences shows, that the rubber solar cable H07 RN-F (of one manufacturer) is not qualified for installations, longer than 10 years. The outer isolation of the cable first shows embrittlements and later deep cracks. Microscopically analysis confirms this. Measurements of temperature in typical installation areas of solar cables also shows, that the influence of temperature, regarding aging plays not the most important role, when the cable is installed in a sun protected position. Up to now the reason of the cable destruction is not definitely clarified. Chemically analysis of a damaged and an intact part of the cable, which was installed inside of a module junction box (reduced humility), shows no differences in the chemical consistence. It seems, that it is a combinated effect of temperature and humidity. Further analysis will be performed. (orig.)

COPPER CABLE RECYCLING TECHNOLOGY

International Nuclear Information System (INIS)

Chelsea Hubbard

2001-01-01

The United States Department of Energy (DOE) continually seeks safer and more cost-effective technologies for use in deactivation and decommissioning (D and D) of nuclear facilities. The Deactivation and Decommissioning Focus Area (DDFA) of the DOE's Office of Science and Technology (OST) sponsors large-scale demonstration and deployment projects (LSDDPs). At these LSDDPs, developers and vendors of improved or innovative technologies showcase products that are potentially beneficial to the DOE's projects and to others in the D and D community. Benefits sought include decreased health and safety risks to personnel and the environment, increased productivity, and decreased costs of operation. The Idaho National Engineering and Environmental Laboratory (INEEL) generated a list of statements defining specific needs and problems where improved technology could be incorporated into ongoing D and D tasks. One such need is to reduce the volume of waste copper wire and cable generated by D and D. Deactivation and decommissioning activities of nuclear facilities generates hundreds of tons of contaminated copper cable, which are sent to radioactive waste disposal sites. The Copper Cable Recycling Technology separates the clean copper from contaminated insulation and dust materials in these cables. The recovered copper can then be reclaimed and, more importantly, landfill disposal volumes can be reduced. The existing baseline technology for disposing radioactively contaminated cables is to package the cables in wooden storage boxes and dispose of the cables in radioactive waste disposal sites. The Copper Cable Recycling Technology is applicable to facility decommissioning projects at many Department of Energy (DOE) nuclear facilities and commercial nuclear power plants undergoing decommissioning activities. The INEEL Copper Cable Recycling Technology Demonstration investigated the effectiveness and efficiency to recycle 13.5 tons of copper cable. To determine the effectiveness

NRC Information Notice No. 92-01: Cable damage caused by inadequate cable installation procedures and controls

International Nuclear Information System (INIS)

Rossi, C.E.

1993-01-01

In June 1989, the Tennessee Valley Authority (TVA) removed the cables from a conduit in the reactor protection system of the Watts Bar Nuclear Plant, Unit 2, to inspect for damage. TVA selected this conduit in response to an employee's concern that a welding arc that struck the conduit in response to an employee's concern that a welding arc that struck the conduit during construction may have damaged cables in the conduit. When the cables were removed, TVA found significant damage in the insulation of some cables. This damage was not attributed to heat generated by the alleged welding arc. The damage was principally attributed to the pulling stresses exerted during the initial installation of the cables. Some of the cables had insulation removed down to the conductors. To assess the extent of cable damage and determine the scope of its investigation, TVA removed more cables from conduits that constituted the most difficult pulls (worst case) and found varying degrees of damage that it attributed to pulling stresses. To fill a conduit at Watts Bar, personnel used pull cords to pull more cables through the conduits over the top of existing cables. This practice is called ''pull-by.'' This practice can cause damage to the existing cables from the sawing action of the pull cords and the friction of cables as they are pulled over existing cables. TVA instituted programs to assess the adequacy of cable installation at all its nuclear facilities and take appropriate corrective actions. At Watts Bar, TVA replaced cables in conduits which exceeded a calculated threshold value of side wall bearing pressure (SWBP) and performed a high-potential (hi-pot) tests on a number of other cables in conduits with SWBP below the calculated threshold value

Energy cable engineering. Energiekabeltechnik

Energy Technology Data Exchange (ETDEWEB)

Luecking, H W

1981-01-01

This textbook intends to explain cable elements and common cable constructions according to VDE, and in a second part, to review the theoretical fundamentals and their consequences with a view to the construction of cables for higher voltages and powers. It will give the student a picture of the variety of problems and solutions which make cable engineering so interesting and show the practising engineer how to derive a theoretical system from their extensive everyday experience.

Field application of a cable NDT system for cable-stayed bridge using MFL sensors integrated

Energy Technology Data Exchange (ETDEWEB)

Kim, Ju Won; Choi, Jun Sung; Park, Seung Hee [Sungkyunkwan University, Seoul (Korea, Republic of); Lee, Eun Chan [Korea Maintance Co., Ltd., Seoul (Korea, Republic of)

2014-02-15

In this study, an automated cable non-destructive testing(NDT) system was developed to monitor the steel cables that are a core component of cable-stayed bridges. The magnetic flux leakage(MFL) method, which is suitable for ferromagnetic continuum structures and has been verified in previous studies, was applied to the cable inspection. A multi-channel MFL sensor head was fabricated using hall sensors and permanent magnets. A wheel-based cable climbing robot was fabricated to improve the accessibility to the cables, and operating software was developed to monitor the MFL-based NDT research and control the climbing robot. Remote data transmission and robot control were realized by applying wireless LAN communication. Finally, the developed element techniques were integrated into an MFL-based cable NDT system, and the field applicability of this system was verified through a field test at Seohae Bridge, which is a typical cable-stayed bridge currently in operation.

Field application of a cable NDT system for cable-stayed bridge using MFL sensors integrated

International Nuclear Information System (INIS)

Kim, Ju Won; Choi, Jun Sung; Park, Seung Hee; Lee, Eun Chan

2014-01-01

In this study, an automated cable non-destructive testing(NDT) system was developed to monitor the steel cables that are a core component of cable-stayed bridges. The magnetic flux leakage(MFL) method, which is suitable for ferromagnetic continuum structures and has been verified in previous studies, was applied to the cable inspection. A multi-channel MFL sensor head was fabricated using hall sensors and permanent magnets. A wheel-based cable climbing robot was fabricated to improve the accessibility to the cables, and operating software was developed to monitor the MFL-based NDT research and control the climbing robot. Remote data transmission and robot control were realized by applying wireless LAN communication. Finally, the developed element techniques were integrated into an MFL-based cable NDT system, and the field applicability of this system was verified through a field test at Seohae Bridge, which is a typical cable-stayed bridge currently in operation.

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

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…

Trend analysis of cables failure events at nuclear power plants

International Nuclear Information System (INIS)

Fushimi, Yasuyuki

2007-01-01

In this study, 152 failure events related with cables at overseas nuclear power plants are selected from Nuclear Information Database, which is owned by The Institute of Nuclear Safety System, and these events are analyzed in view of occurrence, causal factor, and so on. And 15 failure events related with cables at domestic nuclear power plants are selected from Nuclear Information Archives, which is owned by JANTI, and these events are analyzed by the same manner. As a result of comparing both trends, it is revealed following; 1) A cable insulator failure rate is lower at domestic nuclear power plants than at foreign ones. It is thought that a deterioration diagnosis is performed broadly in Japan. 2) Many buried cables failure events have been occupied a significant portion of cables failure events during work activity at overseas plants, however none has been occurred at domestic plants. It is thought that sufficient survey is conducted before excavating activity in Japan. 3) A domestic age related cables failure rate in service is lower than the overseas one and domestic improper maintenance rate is higher than the overseas one. Maintenance worker' a skill improvement is expected in order to reduce improper maintenance. (author)

USING CONDITION MONITORING TO PREDICT REMAINING LIFE OF ELECTRIC CABLES

International Nuclear Information System (INIS)

LOFARO, R.; SOO, P.; VILLARAN, M.; GROVE, E.

2001-01-01

Electric cables are passive components used extensively throughout nuclear power stations to perform numerous safety and non-safety functions. It is known that the polymers commonly used to insulate the conductors on these cables can degrade with time; the rate of degradation being dependent on the severity of the conditions in which the cables operate. Cables do not receive routine maintenance and, since it can be very costly, they are not replaced on a regular basis. Therefore, to ensure their continued functional performance, it would be beneficial if condition monitoring techniques could be used to estimate the remaining useful life of these components. A great deal of research has been performed on various condition monitoring techniques for use on electric cables. In a research program sponsored by the U.S. Nuclear Regulatory Commission, several promising techniques were evaluated and found to provide trendable information on the condition of low-voltage electric cables. These techniques may be useful for predicting remaining life if well defined limiting values for the aging properties being measured can be determined. However, each technique has advantages and limitations that must be addressed in order to use it effectively, and the necessary limiting values are not always easy to obtain. This paper discusses how condition monitoring measurements can be used to predict the remaining useful life of electric cables. The attributes of an appropriate condition monitoring technique are presented, and the process to be used in estimating the remaining useful life of a cable is discussed along with the difficulties that must be addressed

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…

14 CFR 23.689 - Cable systems.

Science.gov (United States)

2010-01-01

... in cable tension throughout the range of travel under operating conditions and temperature variations... 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...

Cables - a question of custom-design

International Nuclear Information System (INIS)

Doig, Tom

1994-01-01

Electrical equipment such as cabling can often be the limiting factor as far as machine operations in radioactive environments are concerned. Electronic and electrical equipment will degrade if exposed to ionising radiation, affecting equipment reliability, or causing complete failure. However, several companies provide custom-designed products directed specifically at the nuclear industry. One such company is Habia Cable which has built up its business in submarine cables, internal engine cables, and cables for high fire risk situations. It began supplying custom-designed cables to the nuclear industry in 1986, and has since then supplied cables throughout Europe from its plant in Sweden. (Author)

Proposed superscreened cables and connectors

International Nuclear Information System (INIS)

Fowler, E.P.

1975-11-01

The paper summarises the present availability of superscreened cables and proposes the specification of a family of cables to meet the foreseeable needs of the nuclear power industry. The cable numbering system is described, special tests outlined and important details given for the chosen cables. Appropriate connectors are also discussed and listed with an outline of their required screening performance. (author)

Applying Diagnostics to Enhance Cable System Reliability (Cable Diagnostic Focused Initiative, Phase II)

Energy Technology Data Exchange (ETDEWEB)

Hartlein, Rick [Georgia Tech Research Corporation (GTRC), Atlanta, GA (United States). National Electric Energy Testing, Research and Applications Center (NEETRAC); Hampton, Nigel [Georgia Tech Research Corporation (GTRC), Atlanta, GA (United States). National Electric Energy Testing, Research and Applications Center (NEETRAC); Perkel, Josh [Georgia Tech Research Corporation (GTRC), Atlanta, GA (United States). National Electric Energy Testing, Research and Applications Center (NEETRAC); Hernandez, JC [Univ. de Los Andes, Merida (Venezuela); Elledge, Stacy [Georgia Tech Research Corporation (GTRC), Atlanta, GA (United States). National Electric Energy Testing, Research and Applications Center (NEETRAC); del Valle, Yamille [Georgia Tech Research Corporation (GTRC), Atlanta, GA (United States). National Electric Energy Testing, Research and Applications Center (NEETRAC); Grimaldo, Jose [Georgia Inst. of Technology, Atlanta, GA (United States). School of Electrical and Computer Engineering; Deku, Kodzo [Georgia Inst. of Technology, Atlanta, GA (United States). George W. Woodruff School of Mechanical Engineering

2016-02-01

The Cable Diagnostic Focused Initiative (CDFI) played a significant and powerful role in clarifying the concerns and understanding the benefits of performing diagnostic tests on underground power cable systems. This project focused on the medium and high voltage cable systems used in utility transmission and distribution (T&D) systems. While many of the analysis techniques and interpretations are applicable to diagnostics and cable systems outside of T&D, areas such as generating stations (nuclear, coal, wind, etc.) and other industrial environments were not the focus. Many large utilities in North America now deploy diagnostics or have changed their diagnostic testing approach as a result of this project. Previous to the CDFI, different diagnostic technology providers individually promoted their approach as the “the best” or “the only” means of detecting cable system defects.

Evaluation of the indenter modulus (IM) method in the international round robin test about the cable condition monitoring

International Nuclear Information System (INIS)

Kajimura, Yuusaku

2016-01-01

In order to ensure the reliability and safety of nuclear power plants, the diagnosis of cable aging is important. The Institute of Nuclear Safety System (INSS) has been developing the indenter modulus (IM) method for more than a dozen years. Its usefulness was demonstrated in the research project 'Assessment of cable aging for nuclear power plant' by the Japan Nuclear Energy Safety Organization in 2009. Furthermore, INSS participated in the IAEA Coordinated Research Project in 2013 to 2015, measuring and acquiring data of insulation materials of cables and cable jackets with insulation which had been never measured before by INSS. The main results are as follows. (1) The IM method is useful for new materials (for example, crosslinked polyolefins) which had never been measured before by INSS. (2) The IM method is also applicable to evaluation of cable jackets with insulation made of such materials as chlorosulfonated polyethylene. Therefore, the IM method is evaluated to be useful and applicable for most cable materials except those which have a high IM value initially and which have a small change in IM value during aging. (author)

Trenchless Replacement of Buried Cable Lines

Directory of Open Access Journals (Sweden)

Hans-Joachim Bayer

2007-01-01

Full Text Available An enormous amount of underground electricity and telecommunication cables have been worn over the time with technical defects or need capacity increases. Thus, new lines need to be installed. In urban areas, even in smaller communities and in natural reserves, open trenching is difficult and often not permitted.In response, new patented methods of trenchless cable replacement using the HDD equipment have been developed by the TT Group. The new technology is called “Wash-over-cable-replacement” and applies specially designed drill heads, cutting around the old cable string in various configurations (completely closed, U-shape or S-shape embracing, depending to the coating type of the old cable. This special cable replacement drill head separates the cable from the surrounding adhesive soil or the sand bedding by creating a very small annular space around the cable thus enabling the pulling or dragging out of the old cable section between the start and the exit pit. After the old cable has been loosened from the surrounding soil by means of the wash over process and pulled out, the new cable can be smoothly pulled into the void using the drill rods and embedding the new cable in a rich bed of Bentonite.The wash-over drill heads are slim and have inner and outer nozzles for Bentonite and bits to handle roots, pebbles, gravel and the like. These drill heads perform very quickly (up to 3 meters per minute to effectively wash over existing cables without damaging the cable coating and prepare the ground for a fast new laying of a new cable in the existing line. Network owners also benefit from the fact that new geodetic or topographic surveys and documentations of the new cable are not necessary. Only the documents, remarks, technical codes and existing geodetic data need to be updated.The paper will outline the technological background and include several practical job examples.

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...... been conducted. The two current prevailing systems consisting of helically filleted cables and cables with a pattern-indented surface were directly compared under the same conditions and both applications were found with attractive properties. The pattern-indented surface maintained a low supercritical...... of reducing the intensity of the axial flow and disrupting the near wake flow structures. Similar studies during wet conditions with artificial simulation of light rain in the wind tunnel showed that the plain cable suffered from severe rain-wind induced vibrations. But despite the presence of both upper...

Shape accuracy optimization for cable-rib tension deployable antenna structure with tensioned cables

Science.gov (United States)

Liu, Ruiwei; Guo, Hongwei; Liu, Rongqiang; Wang, Hongxiang; Tang, Dewei; Song, Xiaoke

2017-11-01

Shape accuracy is of substantial importance in deployable structures as the demand for large-scale deployable structures in various fields, especially in aerospace engineering, increases. The main purpose of this paper is to present a shape accuracy optimization method to find the optimal pretensions for the desired shape of cable-rib tension deployable antenna structure with tensioned cables. First, an analysis model of the deployable structure is established by using finite element method. In this model, geometrical nonlinearity is considered for the cable element and beam element. Flexible deformations of the deployable structure under the action of cable network and tensioned cables are subsequently analyzed separately. Moreover, the influence of pretension of tensioned cables on natural frequencies is studied. Based on the results, a genetic algorithm is used to find a set of reasonable pretension and thus minimize structural deformation under the first natural frequency constraint. Finally, numerical simulations are presented to analyze the deployable structure under two kinds of constraints. Results show that the shape accuracy and natural frequencies of deployable structure can be effectively improved by pretension optimization.

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.

Development of inspection robots for bridge cables.

Science.gov (United States)

Yun, Hae-Bum; Kim, Se-Hoon; Wu, Liuliu; Lee, Jong-Jae

2013-01-01

This paper presents the bridge cable inspection robot developed in Korea. Two types of the cable inspection robots were developed for cable-suspension bridges and cable-stayed bridge. The design of the robot system and performance of the NDT techniques associated with the cable inspection robot are discussed. A review on recent advances in emerging robot-based inspection technologies for bridge cables and current bridge cable inspection methods is also presented.

BC Hydro's integrated approach on replacing underground feeder cables

Energy Technology Data Exchange (ETDEWEB)

Tarampi, D. [BC Hydro, Burnaby, BC (Canada)

2008-07-01

BC Hydro's integrated approach on replacing underground feeder cables was discussed. The feeder cables were all in ducts encased in concrete and splices were identified in concrete manholes. The feeder cables averaged 35 to 40 failures per year, with a large majority of failures occurring in manholes or near terminations. The age of the cables was not known. A graphical representation of a condition assessment was presented with reference to an electrical test, metallurgical test, hardness test, and dye penetrating test. Prioritization steps were also listed, including a condition index and replacement threshold. Steps in prioritizing the condition index included determining the insulation index based on electrical test results; determining the manhole condition based on metallurgical test results; determining the customer importance factor and feeder load factor; and calculating the overall condition index based on the indices. A process flowchart was also illustrated. A replacement strategy was then discussed and a cost comparison of two options was described. Option 1 was to replace only the unjacketed cables while option two involved selective replacement. tabs., figs.

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.

Environmental Impact of a Submarine Cable: Case Study of the Acoustic Thermometry of Ocean Climate (ATOC)/ Pioneer Seamount Cable

Science.gov (United States)

Kogan, I.; Paull, C. K.; Kuhnz, L.; von Thun, S.; Burton, E.; Greene, H. G.; Barry, J. P.

2003-12-01

To better understand the potential impacts of the presence of cables on the seabed, a topic of interest for which little data is published or publicly available, a study of the environmental impacts of the ATOC/Pioneer Seamount cable was conducted. The 95 km long, submarine, coaxial cable extends between Pioneer Seamount and the Pillar Point Air Force Station in Half Moon Bay, California. Approximately two thirds of the cable lies within the Monterey Bay National Marine Sanctuary. The cable is permitted to NOAA- Oceanic and Atmospheric Research for transmitting data from a hydrophone array on Pioneer Seamount to shore. The cable was installed unburied on the seafloor in 1995. The cable path crosses the continental shelf, descends to a maximum depth of 1,933 m, and climbs back upslope to 998 m depth near the crest of Pioneer Seamount. A total of 42 hours of video and 152 push cores were collected in 10 stations along cable and control transects using the ROVs Ventana and Tiburon equipped with cable-tracking tools. The condition of the cable, its effect on the seafloor, and distribution of benthic megafauna and infauna were determined. Video data indicated the nature of interaction between the cable and the seafloor. Rocky nearshore areas, where wave energies are greatest, showed the clearest evidence of impact. Here, evidence of abrasion included frayed and unraveling portions of the cable's armor and vertical grooves in the rock apparently cut by the cable. The greatest incision and armor damage occurred on ledges between spans in irregular rock outcrop areas. Unlike the nearshore rocky region, neither the rocks nor the cable appeared damaged along outcrops on Pioneer Seamount. Multiple loops of slack cable added during a 1997 cable repair operation were found lying flat on the seafloor. Several sharp kinks in the cable were seen at 240 m water depths in an area subjected to intense trawling activity. Most of the cable has become buried with time in sediment

Optimal Cable Tension Distribution of the High-Speed Redundant Driven Camera Robots Considering Cable Sag and Inertia Effects

Directory of Open Access Journals (Sweden)

Yu Su

2014-03-01

Full Text Available Camera robots are high-speed redundantly cable-driven parallel manipulators that realize the aerial panoramic photographing. When long-span cables and high maneuverability are involved, the effects of cable sags and inertias on the dynamics must be carefully dealt with. This paper is devoted to the optimal cable tension distribution (OCTD for short of the camera robots. Firstly, each fast varying-length cable is discretized into some nodes for computing the cable inertias. Secondly, the dynamic equation integrated with the cable inertias is set up regarding the large-span cables as catenaries. Thirdly, an iterative optimization algorithm is introduced for the cable tension distribution by using the dynamic equation and sag-to-span ratios as constraint conditions. Finally, numerical examples are presented to demonstrate the effects of cable sags and inertias on determining tensions. The results justify the convergence and effectiveness of the algorithm. In addition, the results show that it is necessary to take the cable sags and inertias into consideration for the large-span manipulators.

A unique cabling designed to produce Rutherford-type superconducting cable for the SSC project

International Nuclear Information System (INIS)

Grisel, J.; Royet, J.M.; Scanlan, R.M.; Armer, R.

1988-08-01

Up to 25,000 Km of keystoned flat cable must be produced for the SSC project. Starting from a specification developed by Lawrence Berkeley Laboratory (LBL), a special cabling machine has been designed by Dour Metal. It has been designed to be able to run at a speed corresponding to a maximum production rate of 10 m/min. This cabling machine is the key part of the production line which consists of a precision Turkshead equipped with a variable power drive, a caterpillar, a dimensional control bench, a data acquisition system, and a take-up unit. The main features of the cabling unit to be described are a design with nearly equal path length between spool and assembling point for all the wires, and the possibility to run the machine with several over- or under-twisting ratios between cable and wires. These requirements led Dour Metal to the choice of an unconventional mechanical concept for a cabling machine. 4 refs., 2 figs

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...

Development of Inspection Robots for Bridge Cables

Directory of Open Access Journals (Sweden)

Hae-Bum Yun

2013-01-01

Full Text Available This paper presents the bridge cable inspection robot developed in Korea. Two types of the cable inspection robots were developed for cable-suspension bridges and cable-stayed bridge. The design of the robot system and performance of the NDT techniques associated with the cable inspection robot are discussed. A review on recent advances in emerging robot-based inspection technologies for bridge cables and current bridge cable inspection methods is also presented.

How do you like them cables?

CERN Multimedia

Sergei Malyukov

Cabling work is not for clautrophobic people! Cables are like the blood vessels and nervous system of ATLAS. With the help of all these cables, we can power ATLAS, control the detector and read out the data. Like the human blood vessels, they penetrate inside the ATLAS volume, reaching each of its elements. The ATLAS developers started to think about design of services, cables and pipes at the very first stages of the project. The cabling project has been developing most intensively during the last five years, passing through the projection and CAD design phases, then the installation of cable trays and finally the cables. The cable installation itself took two and a half years and was done by teams of technicians from several institutes from Russia, the Czech Republic and Poland. Here are some numbers to illustrate the scale of the ATLAS cabling system. More than 25000 optical fiber channels are used for reading the information from the sub-detectors and delivering the timing signals. The total numbe...

Dynamical Analysis and Simulation Validation of Incompletely Restrained Cable-Suspended Swinging System Driven by Two Cables

Directory of Open Access Journals (Sweden)

Naige Wang

2016-01-01

Full Text Available The flexibility of the suspension multicables and driven length difference between two cables cause the translation and rotation of the platform in the incompletely restrained cable-suspended system driven by two cables (IRCSWs2, which are theoretically investigated in this paper. The suspension cables are spatially discretized using the assumed modes method (AMM and the equations of motion are derived from Lagrange equations of the first kind. Considering all the geometric matching conditions are approximately linear with external actuator, the differential algebraic equations (DAEs are transformed to a system of ordinary differential equations (ODEs. Using linear boundary conditions of the suspension cable, the current method can obtain not only the accurate longitudinal displacements of cable and posture of the platform, but also the tension between the platform and cables, and the current method is verified by ADAMS simulation.

Instrumentation Cables Test Plan

Energy Technology Data Exchange (ETDEWEB)

Muna, Alice Baca [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); LaFleur, Chris Bensdotter [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

2016-10-01

A fire at a nuclear power plant (NPP) has the potential to damage structures, systems, and components important to safety, if not promptly detected and suppressed. At Browns Ferry Nuclear Power Plant on March 22, 1975, a fire in the reactor building damaged electrical power and control systems. Damage to instrumentation cables impeded the function of both normal and standby reactor coolant systems, and degraded the operators’ plant monitoring capability. This event resulted in additional NRC involvement with utilities to ensure that NPPs are properly protected from fire as intended by the NRC principle design criteria (i.e., general design criteria 3, Fire Protection). Current guidance and methods for both deterministic and performance based approaches typically make conservative (bounding) assumptions regarding the fire-induced failure modes of instrumentation cables and those failure modes effects on component and system response. Numerous fire testing programs have been conducted in the past to evaluate the failure modes and effects of electrical cables exposed to severe thermal conditions. However, that testing has primarily focused on control circuits with only a limited number of tests performed on instrumentation circuits. In 2001, the Nuclear Energy Institute (NEI) and the Electric Power Research Institute (EPRI) conducted a series of cable fire tests designed to address specific aspects of the cable failure and circuit fault issues of concern1. The NRC was invited to observe and participate in that program. The NRC sponsored Sandia National Laboratories to support this participation, whom among other things, added a 4-20 mA instrumentation circuit and instrumentation cabling to six of the tests. Although limited, one insight drawn from those instrumentation circuits tests was that the failure characteristics appeared to depend on the cable insulation material. The results showed that for thermoset insulated cables, the instrument reading tended to drift

Ageing management program of wires for Atucha II Nuclear Power Plant

International Nuclear Information System (INIS)

Zorrilla, J.; Antonaccio, E.; Luraschi, C.; Simionato, E.; Nieto, H.

2012-01-01

Electrical cables constitute one of the most important components of NPP in terms o maintenance, safety and availability of the plant. Due to their large extension (thousands of kilometers) it is impossible to fully replace them and aging management becomes essential for long term operation of NPP. Since Atucha II is under construction there was a good opportunity to establish and implement a holistic cable aging management program from the beginning according to the state of the art in this field. The scope of this program involves safety related cables, including EQ cables and non EQ cables as well. Due to the diversity of the installed cables is impossible to address an aging management program of every single specimen. However it is possible to establish 'cables families' of similar aging behavior based on insulation and jacket material, manufacture, etc Several aging management strategies were set for the different 'cables families'. These strategies include cables deposit in plant, elaboration of procedures of visual and tactile inspection, NDE techniques, etc Currently the aging management program is being implemented covering topic such as: Cable screening and grouping. Review of EQ documentation and conventional qualification information referring to the installed cables. Establishment of base line of condition monitoring techniques. Calibration and set up of test parameters for NDE techniques. Aging mechanism characterization and determination of. Design construction and installation of cable deposit in plant (author)

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 overheat...

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...

Cable handling

International Nuclear Information System (INIS)

1980-01-01

In computerized axial tomography scanning, problems arise in exchanging electrical signals between fixed and rotating assemblies. A novel method of overcoming this problem is described in detail for both signal and high voltage cables. Apparatus using a sequence of drums and pulleys is used to maintain the interconnecting cables in a neat arrangement and free from mechanical strain. The apparatus is simple and relatively easy and inexpensive to assemble and maintain. (UK)

The RHIC transfer line cable database

International Nuclear Information System (INIS)

Scholl, E.H.; Satogata, T.

1995-01-01

A cable database was created to facilitate and document installation of cables and wiring in the RHIC project, as well as to provide a data source to track possible wiring and signal problems. The eight tables of this relational database, currently implemented in Sybase, contain information ranging from cable routing to attenuation of individual wires. This database was created in a hierarchical scheme under the assumption that cables contain wires -- each instance of a cable has one to many wires associated with it. This scheme allows entry of information pertinent to individual wires while only requiring single entries for each cable. Relationships to other RHIC databases are also discussed

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,

30 CFR 18.45 - Cable reels.

Science.gov (United States)

2010-07-01

... and locomotives shall maintain positive tension on the portable cable during reeling and unreeling. Such tension shall only be high enough to prevent a machine from running over its own cable(s). (e... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Cable reels. 18.45 Section 18.45 Mineral...

14 CFR 25.689 - Cable systems.

Science.gov (United States)

2010-01-01

... cable system must be designed so that there will be no hazardous change in cable tension throughout the... 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...

Time domain spectroscopy to monitor the condition of cable insulation

International Nuclear Information System (INIS)

Mopsik, F.I.; Martzloff, F.D.

1989-01-01

The use of Time Domain Spectroscopy, the measurement of dielectric constant and loss using time-domain response, the monitoring the aging of reactor cable insulation is examined. The method is presented, showing its sensitivity, accuracy and wide frequency range. The method's ability to acquire a great deal of information in a short time and its superiority to conventional single frequency data is shown. Different cable samples are examined before and after exposure to radiation and changes with exposure are clearly seen to occur. Also it is shown that a wide range of behavior can be found in different insulation systems. The requirements for performing valid measurements is presented. The need for controlled samples and correlation with other criteria for aging is discussed. 14 refs., 9 figs

Lightning-resistant, low-inductance detonator cables

Energy Technology Data Exchange (ETDEWEB)

Druce, R.L.; Lee, R.S.; Moua, K.

1994-04-01

A lightning strike on a flat detonator cable in close proximity to a high explosive (HE) main charge poses a possible detonation hazard if the electrical explosion of the cable launches the dielectric cover coat of the cable at a high enough velocity to shock-initiate the HE. The detonator cable for the W87 system has been demonstrated to be incapable of initiating LX-17 main-charge explosive even for a 99 percentile negative lightning strike (1). The W87 cable is a relatively high inductance cable, unsuitable for use with low-inductance firesets. We have performed tests on a low-inductance cable designed for the W89 program, which show it to be marginal in its ability to withstand a lightning strike without the possibility of initiating a heated LX-17 main charge HE. A new cable design, proposed by R.E. Lee of LLNL has been tested and shown to be capable of withstanding a 99 percentile negative lightning strike without initiating LX-17 heated to 250{degree}C.

Aerodynamics of the cable of cable-stayed bridges; Shachokyo cable no kuriki shindo tokusei no rikai to soreni motozuku kuriki seishinho no teian

Energy Technology Data Exchange (ETDEWEB)

Matsumoto, M. [Kyoto University, Kyoto (Japan). Faculty of Engineering; Aoki, J.; Fuji, D. [West Japan Railway Company, Osaka (Japan); Kitayama, N. [Ishikawajima-Harima Heavy Industries Co. Ltd., Tokyo (Japan); Daito, Y. [Kyoto University, Kyoto (Japan)

1996-07-21

Wind tunnel tests were conducted assuming the aerodynamics of the cable of cable-stayed bridges especially in the case of strong wind with rain. Based on the results, an aerodynamic damping method was proposed. Factors of the rain vibration generation include the three-dimensional axial flow behind the cable, which is formed by the wind direction deviation angle, the upper side water flow on the cable surface formed by the rain, and the Karman vortex shedding, which are not uniform in the span direction. Newly proposed cable with elliptical plates showed an effective dumping performance. It restrains the formation of water flow due to its profile, and is effective for unstableness due to water flow formation. Distribution of the axial flow in the cable span direction was made clear. Three-dimensionality of the vortex shedding was greatly affected by this axial flow. Frequency of the Karman vortex shedding changed in the wide band by the axial flow. It was suggested that three-dimensionality of the flow field is enhanced by the rolling vibration, resulting in the unstableness of heaving vibration. 5 refs., 15 figs.

Composite carbon fiber cables; Des cables composites en fibres de carbone

Energy Technology Data Exchange (ETDEWEB)

Anon.

2002-10-01

In order to fulfill the requirements of offshore engineering, Freyssinet, a daughter company of the European Vinci group, has developed a series of high-performance carbon fiber cables. These composite materials have an excellent fatigue behaviour in a huge range of constraints. Moreover, their low weight allows the implementation of very long lengths of cables in marine environment with no loss in capacity. The specific weight of the current part of the cable is reduced by a factor of 4 with respect to an equivalent capacity armature made of steel. These materials were presented in June 2002 at the ultra deep engineering and technologies (UDET) exhibition of Brest (France). (J.S.)

Understanding losses in three core armoured submarine cables

DEFF Research Database (Denmark)

Silva, Filipe Miguel Faria da; Ebdrup, Thomas; Bak, Claus Leth

2016-01-01

. For practical an economical reasons the preferred choice of cable for both the array and the transmission cables are three-core armoured submarine cables. Therefore, it has becoming increasingly important to be able to calculate the ampacity of such cables accurately. At present time, the ampacity of three......-core armoured submarine cables is calculated according to IEC 60287-1-1 [1]. Various measurements conducted both by cable manufacturers and transmission system operators (TSO) have shown that using the cable rating method stated in IEC 60287-1-1 underestimates the cable ampacity [2]-[6]. Furthermore......, measurements conducted within the cable industry have shown that an armoured three core cable has higher losses than equal unarmoured three core cables. It is also suggested that the inaccuracy in the IEC armour’s loss factor (λ2) is the main responsible for the conservatism in the IEC cable rating method...

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...... 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...... 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...

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.

High voltage dc cables

Energy Technology Data Exchange (ETDEWEB)

Bjustrom, B

1965-12-01

How stress distribution in dc cables varies with temperature and stress level, influence of polarity reversals and space charges, and different types of overvoltage to which dc cable may be subjected are discussed. Design problems, especially as related to corrosion protection and to mechanical stress caused by wire armoring during manufacturing and laying, accessories and work done on test methods, and the possibility of designing 400 to 600 kV dc cables for transmitting 2000 to 4000 MW are described.

In search of extendable conditions for cable environmental qualification in nuclear power plants

International Nuclear Information System (INIS)

Alshaketheep, Tariq; Sekimura, Naoto; Itoi, Tatsuya; Murakami, Kenta

2016-01-01

The environmental qualification (EQ) for cable insulators in nuclear power plants (NPPs) has been developed on the basis of the design basis accident (DBA) to prevent reactor core damage. However, the latest safety principles require extending the design concept to prepare the utilized equipment for scenarios after core damage. Thus, we propose a modification to the EQ for cables connecting utilized equipment at design extension conditions. This paper surveys all electrical components for accident management in boiling water reactor-4 (BWR-4), and identifies their connecting cables' functional category as low-voltage power, instrumentation, and control cables. The EQ temperature profile of these cables during the incident phase was addressed for extension. This required postulating maximum temperature environments according to accident scenarios, knowledge of cable integrity degradation, and their current evaluation by the EQ. To evaluate whether these environments are suitable stressors, heat testing was conducted on flame-retardant ethylene propylene rubber (FR-EPR)-insulated cables. On the basis of those results, we suggest a maximum primary peak temperature of the EQ temperature profile of 250degC. We also suggest increasing the primary peak period of the EQ temperature profile to 48 h without experiment, on the basis of inherent excessive margin for mechanical integrity during the ageing phase. (author)

Long-term test of the 22.9kV HTS power cable system in LS Cable Ltd

International Nuclear Information System (INIS)

Jang, Hyun Man; Lee, Chang Young; Kim, Choon Dong; Kim, Do Hyung; Park, In Son; Ji, Bong Ki; Kim, Dong Wook; Cho, Jeonwook

2006-01-01

Since 2001, LS cable Ltd. has been developing the design, manufacturing and evaluation technologies for high temperature superconducting (HTS) power cable system as a member of DAPAS (Dream for Advanced Power system by Applied Superconductivity technology) program in Korea. The 30 m HTS cable system that is rated at 22.9 kV and 1.2 kA giving a rated capacity of 50 MVA had been developed and tested. The cable was designed as a cold dielectric type employing Bi-2223 HTS tapes and polypropylene (PP) laminated paper as the conductor and electrical insulation, respectively. The cable is cooled with sub-cooled liquid nitrogen at temperature from 75 to 77 K. The manufacturing and the installation of the cable system were completed in 2004. Long-term performance test of the cable system has been conducted for six months to verify its electric and mechanical properties in 2005

Self-healing cable for extreme environments

Science.gov (United States)

Huston, Dryver R. (Inventor); Tolmie, Bernard R. (Inventor)

2009-01-01

Self-healing cable apparatus and methods disclosed. The self-healing cable has a central core surrounded by an adaptive cover that can extend over the entire length of the self-healing cable or just one or more portions of the self-healing cable. The adaptive cover includes an axially and/or radially compressible-expandable (C/E) foam layer that maintains its properties over a wide range of environmental conditions. A tape layer surrounds the C/E layer and is applied so that it surrounds and axially and/or radially compresses the C/E layer. When the self-healing cable is subjected to a damaging force that causes a breach in the outer jacket and the tape layer, the corresponding localized axially and/or radially compressed portion of the C/E foam layer expands into the breach to form a corresponding localized self-healed region. The self-healing cable is manufacturable with present-day commercial self-healing cable manufacturing tools.

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

International Nuclear Information System (INIS)

Subudhi, M.

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

Analytical and numerical construction of equivalent cables.

Science.gov (United States)

Lindsay, K A; Rosenberg, J R; Tucker, G

2003-08-01

The mathematical complexity experienced when applying cable theory to arbitrarily branched dendrites has lead to the development of a simple representation of any branched dendrite called the equivalent cable. The equivalent cable is an unbranched model of a dendrite and a one-to-one mapping of potentials and currents on the branched model to those on the unbranched model, and vice versa. The piecewise uniform cable, with a symmetrised tri-diagonal system matrix, is shown to represent the canonical form for an equivalent cable. Through a novel application of the Laplace transform it is demonstrated that an arbitrary branched model of a dendrite can be transformed to the canonical form of an equivalent cable. The characteristic properties of the equivalent cable are extracted from the matrix for the transformed branched model. The one-to-one mapping follows automatically from the construction of the equivalent cable. The equivalent cable is used to provide a new procedure for characterising the location of synaptic contacts on spinal interneurons.

Superconducting flat tape cable magnet

Science.gov (United States)

Takayasu, Makoto

2015-08-11

A method for winding a coil magnet with the stacked tape cables, and a coil so wound. The winding process is controlled and various shape coils can be wound by twisting about the longitudinal axis of the cable and bending following the easy bend direction during winding, so that sharp local bending can be obtained by adjusting the twist pitch. Stack-tape cable is twisted while being wound, instead of being twisted in a straight configuration and then wound. In certain embodiments, the straight length should be half of the cable twist-pitch or a multiple of it.

47 CFR 27.1202 - Cable/BRS cross-ownership.

Science.gov (United States)

2010-10-01

... portion of the franchise area actually served by the cable operator's cable system and the cable operator... franchise area actually served by the cable operator's cable system the cable operator will use the BRS... that no portion of the GSA of the BRS station is within the portion of the franchise area actually...

Regulatory instrument review: Aging management of LWR cables, containment and basemat, reactor coolant pumps, and motor-operated valves

International Nuclear Information System (INIS)

Werry, E.V.; Somasundaram, S.

1995-09-01

The results of Stage 2 of the Regulatory Instrument Review are presented in this volume. Selected regulatory instruments, such as the Code of Federal Regulations (CFR), US Nuclear Regulatory Commission (NRC), Regulatory Guides, and ASME Codes, were investigated to determine the extent to which these regulations apply aging management to selected safety-related components in nuclear power plants. The Regulatory Instrument Review was funded by the NRC under the Nuclear Plant Aging Research (NPAR) program. Stage 2 of the review focused on four safety-related structures and components; namely, cables, containment and basemat, reactor coolant pumps, and motor-operated valves. The review suggests that the primary-emphasis of the regulatory instruments was on the design, construction, start-up, and operation of a nuclear power plant, and that aging issues were primarily addressed after an aging-related problem was recognized. This Stage 2 review confirms the results of the prior review; (see Regulatory Instrument Review: Management of Aging of LWR Major Safety-Related Components NUREG/CR-5490. The observations indicate that the regulations generally address management of age-related degradation indirectly. Specific age-related degradation phenomena frequently are dealt with in bulletins and notices or through generic issues, letters, etc. The major recommendation of this report, therefore, is that the regulatory instruments should more directly and explicitly address the aging phenomenon and the management of the age-related degradation process

The analysis of cable forces based on natural frequency

Science.gov (United States)

Suangga, Made; Hidayat, Irpan; Juliastuti; Bontan, Darwin Julius

2017-12-01

A cable is a flexible structural member that is effective at resisting tensile forces. Cables are used in a variety of structures that employ their unique characteristics to create efficient design tension members. The condition of the cable forces in the cable supported structure is an important indication of judging whether the structure is in good condition. Several methods have been developed to measure on site cable forces. Vibration technique using correlation between natural frequency and cable forces is a simple method to determine in situ cable forces, however the method need accurate information on the boundary condition, cable mass, and cable length. The natural frequency of the cable is determined using FFT (Fast Fourier Transform) Technique to the acceleration record of the cable. Based on the natural frequency obtained, the cable forces then can be determine by analytical or by finite element program. This research is focus on the vibration techniques to determine the cable forces, to understand the physical parameter effect of the cable and also modelling techniques to the natural frequency and cable forces.

Aluminium cables in automotive applications : Prestudy of aluminium cable uses in Scania products&Failure analysis and evaluation

OpenAIRE

Man, Yu

2016-01-01

The increasing demand of light constructed vehicles as well as soaring price of copper metal owing to limited nature resources have been promoting the use of aluminium metal as an alternative conductor of automotive cables. This thesis work is to lay theoretical foundations for further research and development regarding the introduction of new automotive cables i.e. aluminium cables. Current application of automotive aluminium cables in automotive industry as well as failure analysis and eval...

Initial tension loss in cerclage cables.

Science.gov (United States)

Ménard, Jérémie; Émard, Maxime; Canet, Fanny; Brailovski, Vladimir; Petit, Yvan; Laflamme, George Y

2013-10-01

Cerclage cables, frequently used in the management of fractures and osteotomies, are associated with a high failure rate and significant loosening during surgery. This study compared the capacity to maintain tension of different types of orthopaedic cable systems. Multifilament Cobalt-Chrome (CoCr) cables with four different crimp/clamp devices (DePuy, Stryker, Zimmer and Smith&Nephew) and one non-metallic Nylon (Ny) cable from Kinamed were instrumented with a load cell to measure tension during insertion. Significant tension loss was observed with crimping for all cables (Ptensioner led to an additional unexpected tension loss (CoCr-DePuy: 18%, CoCr-Stryker: 29%, CoCr-Smith&Nephew: 33%, Ny: 46%, and CoCr-Zimmer: 52%). The simple CoCr (DePuy) cable system outperformed the more sophisticated locking devices due to its significantly better ability to prevent tension loss. Copyright © 2013 Elsevier Inc. All rights reserved.

Power cables now and in the future

Energy Technology Data Exchange (ETDEWEB)

Wanser, G

1976-01-01

A survey is presented of the problems to be faced with the underground supply of electric power to large, urban areas and of the contributions that improvements in power cable technology will make to solving these problems. It is concluded that the increase in population densities and the rising demand for energy on the part of individual consumers bring up problems for electricity supply and thus have a direct influence on development trends in cable engineering. During the last few years the increasing capacities required in power transmission have led to the use of higher voltages and to the application of special methods of cooling for the oil-filled cable. When the technical and economic possibilities with present-day cable techniques have been exhausted, we must anticipate the introduction of new types of cable, i.e., gas-insulated cables and superconducting cables. The problems involved in power distribution are being solved successfully by resorting to larger conductor cross-sectional areas and by raising the voltage levels. The advantages of plastic cables are also being utilized on a wide scale. The requirement that there be freedom from partial discharges in plastic cables operating at medium and higher voltages is becoming increasingly more widely adopted as a new quality criterion in cable engineering. New materials from the polymer range are permitting the introduction of fittings which are easier to install and which reduce costs. Cable engineering has already, to a considerable extent, adapted itself to face future problems. Even so, there are still a large number of problems in cable engineering requiring research, development and operation.

Impact of Cross-Tie Properties on the Modal Behavior of Cable Networks on Cable-Stayed Bridges.

Science.gov (United States)

Ahmad, Javaid; Cheng, Shaohong; Ghrib, Faouzi

2015-01-01

Dynamic behaviour of cable networks is highly dependent on the installation location, stiffness, and damping of cross-ties. Thus, these are the important design parameters for a cable network. While the effects of the former two on the network response have been investigated to some extent in the past, the impact of cross-tie damping has rarely been addressed. To comprehend our knowledge of mechanics associated with cable networks, in the current study, an analytical model of a cable network will be proposed by taking into account both cross-tie stiffness and damping. In addition, the damping property of main cables in the network will also be considered in the formulation. This would allow exploring not only the effectiveness of a cross-tie design on enhancing the in-plane stiffness of a constituted cable network, but also its energy dissipation capacity. The proposed analytical model will be applied to networks with different configurations. The influence of cross-tie stiffness and damping on the modal response of various types of networks will be investigated by using the corresponding undamped rigid cross-tie network as a reference base. Results will provide valuable information on the selection of cross-tie properties to achieve more effective cable vibration control.

Impact of Cross-Tie Properties on the Modal Behavior of Cable Networks on Cable-Stayed Bridges

Directory of Open Access Journals (Sweden)

Javaid Ahmad

2015-01-01

Full Text Available Dynamic behaviour of cable networks is highly dependent on the installation location, stiffness, and damping of cross-ties. Thus, these are the important design parameters for a cable network. While the effects of the former two on the network response have been investigated to some extent in the past, the impact of cross-tie damping has rarely been addressed. To comprehend our knowledge of mechanics associated with cable networks, in the current study, an analytical model of a cable network will be proposed by taking into account both cross-tie stiffness and damping. In addition, the damping property of main cables in the network will also be considered in the formulation. This would allow exploring not only the effectiveness of a cross-tie design on enhancing the in-plane stiffness of a constituted cable network, but also its energy dissipation capacity. The proposed analytical model will be applied to networks with different configurations. The influence of cross-tie stiffness and damping on the modal response of various types of networks will be investigated by using the corresponding undamped rigid cross-tie network as a reference base. Results will provide valuable information on the selection of cross-tie properties to achieve more effective cable vibration control.

High-voltage polymeric insulated cables

Energy Technology Data Exchange (ETDEWEB)

Ross, A

1987-01-01

Reviews developments in high-voltage (here defined as 25 kV, 66 kV and 132 kV) polymeric insulated cables in the UK over the period 1979-1986, with particular reference to the experience of the Eastern Electricity Board. Outlines the background to the adoption of XPLE-insulated solid cable, and the design, testing, terminations, jointing and costs of 25 kV, 66 kV and 132 kV cables.

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

Study of special spacer with damping device for suppressing wake galloping in tandem cables of cable-stayed bridges and its application to full scale bridge; Nendanseitai wo riyoshita heiretsu cable yo gensui kinotsuki spacer to sono jikkyo cable eno tekiyo ni kansuru kenkyu

Energy Technology Data Exchange (ETDEWEB)

Yoneda, M.; Setouchi, H.; Yoshioka, A. [Kawada Industries Inc., Tokyo (Japan); Shimoda, I.; Kawahara, S. [Oiles Corp., Tokyo (Japan)

1996-12-20

Cable vibration called wake galloping occurs in a cable-stayed bridge, in which cables are arranged tandem, and suppression of the vibration is an extremely important discussion item. This paper describes a complex eigen value analysis performed on tandem cables having lengths of 200 m and 100 m. The analysis revealed that damping characteristics added by a spacer system with a damping device (a type to install a visco-elastic body at about middle of the tandem cables via a jig) depend largely on torsional rigidity of the cables; and the characteristics may vary with difference in intervals between cable centers and that in cable diameters. A visco-elastic damping material of an asphalt system and a spacer with a damping device used as a spring material were fabricated and applied to a full scale bridge to identify quantitatively the damping addition characteristics of this system. Furthermore, the results of tests on the full scale bridge were compared with the result of the complex eigen value analysis, from which findings useful for actual works were obtained. 18 refs., 17 figs., 6 tabs.

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…

Effect of Concrete Creep on the displacement of single tower single cable plane Extradosed Cable-stayed Bridge

Science.gov (United States)

Shi, Jing-xian; Ran, Zhi-hong

2018-03-01

Extradossed Cable-stayed Bridge is both cable-stayed Bridge and Continuous rigid frame bridge mechanics feature, Beam is the main force components, cable is supplement.This article combined with a single tower and single cable plane Extradossed cable-stayed bridge in Yunnan, use different creep calculation models and analysis deflection caused by creep effects. The results showing that deflection caused by creep effect is smaller than the same span continuous rigid frame bridge, the value is about 2cm. On the other hand the deflection is increasing with ambient humidity decreases, therefore in the dry environment the calculation model is relatively large in the pre-camber. In the choice of RC creep model is significant in the dry areas.

46 CFR 111.60-5 - Cable installation.

Science.gov (United States)

2010-10-01

... REQUIREMENTS Wiring Materials and Methods § 111.60-5 Cable installation. (a) Each cable installation must meet... 46 Shipping 4 2010-10-01 2010-10-01 false Cable installation. 111.60-5 Section 111.60-5 Shipping... incorporated by reference; see 46 CFR 110.10-1), including clause 8. (b) Each cable installation made in...

Evaluation of diagnostic technique for degradation of low-voltage electric cables with silicone rubber insulator

International Nuclear Information System (INIS)

Mikami, Masao

2005-01-01

As a part of countermeasures against ageing problems of nuclear power plants, it is requested to establish non-destructive diagnostic technique for their degradation of low voltage electric cables and assessment standard of their life. Having aimed at investigating the degradation of low-voltage electric cable with silicone rubber insulator, change of its surface hardness at elevated temperature were measured by indenter modules. Moreover, we also measured the elongation at break, which is regarded as general degradation index of electric cables, and the surface hardness with a micro hardness meter. Consequently, it is seen that the indenter modulus measurement is (1) capable to obtain general feature of the thermal degradation of silicone rubber insulator, (2) applicable to diagnose the degree of degradation of the electric cable by converting the result to elongation at break, (3) well correlated with the hardness measurement of the electric cable with the micro hardness meter. (author)

Pilot study on the management of ageing of instrumentation and control cables. Results of a co-ordinated research programme 1993-1995

International Nuclear Information System (INIS)

1997-03-01

Although few problems have been reported with cables in normal operation of NPPs, there have been some cases where cables which had initially been qualified for a 40 year service life failed a design basis event test after removal from the plant following less than 10 years of normal operation. This report presents recommendations of Coordinated Research Programmes participants for ongoing qualification and condition monitoring methods that can be used in NPPs to provide additional assurance for the safety of cables inside containment. The report will be of interest to NPP designers, operators, regulators, technical support organizations and researchers interested in electrical and I and C cable qualification programmes. 19 refs, 8 figs, 1 tab

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.

Simple Program to Investigate Hysteresis Damping Effect of Cross-Ties on Cables Vibration of Cable-Stayed Bridges

Directory of Open Access Journals (Sweden)

Panagis G. Papadopoulos

2012-01-01

Full Text Available A short computer program, fully documented, is presented, for the step-by-step dynamic analysis of isolated cables or couples of parallel cables of a cable-stayed bridge, connected to each other and possibly with the deck of the bridge, by very thin pretensioned wires (cross-ties and subjected to variation of their axial forces due to traffic or to successive pulses of a wind drag force. A simplified SDOF model, approximating the fundamental vibration mode, is adopted for every individual cable. The geometric nonlinearity of the cables is taken into account by their geometric stiffness, whereas the material nonlinearities of the cross-ties include compressive loosening, tensile yielding, and hysteresis stress-strain loops. Seven numerical experiments are performed. Based on them, it is observed that if two interconnected parallel cables have different dynamic characteristics, for example different lengths, thus different masses, weights, and geometric stiffnesses, too, or if one of them has a small additional mass, then a single pretensioned very thin wire, connecting them to each other and possibly with the deck of the bridge, proves effective in suppressing, by its hysteresis damping, the vibrations of the cables.

Fatigue of cable anchorage of large cable stayed bridge; Daikibo shachokyo cable teichaku kozo no hiro

Energy Technology Data Exchange (ETDEWEB)

Endo, T.; Matsumoto, T. [Honshu-Shikoku Bridge Authority, Tokyo (Japan); Tsukahara, H. [Yokogawa Bridge Corp., Tokyo (Japan); Miki, C. [Tokyo Institute of Technology, Tokyo (Japan)

1995-10-21

Design considerations such as design schemes, the assemblage and welding of steel plates, and safety for fatigue of welded connections have to be taken for the cable anchorages of the steel cable stayed bridges. In this study, two full scale models, which have different shape of box anchorages welded to the web of the main girder, were made to investigate fatigue characteristics as well as assemblage of plate and gelding details. Finite element analyses for both test models and actual bridges here carried out to compare stress distribution. It was confirmed that the assemblage and welding of both types of box anchorage were attainable kith required quality and accuracy. According to the fatigue test, fatigue cracks originated from the weldings of the bearing plate to which the load from cable socket applied directly were caused by out-of-plane bending of the bearing plate. It was proved that the slight modifications of the details around the bearing plate resulted in sufficient fatigue strength in both types of anchorage. 1 ref., 23 figs., 2 tabs.

Cable SGEMP Code Validation Study

Energy Technology Data Exchange (ETDEWEB)

Ballard, William Parker [Sandia National Lab. (SNL-CA), Livermore, CA (United States). Center for CA Weapons Systems Engineering

2013-05-01

This report compared data taken on the Modular Bremsstrahlung Simulator using copper jacketed (cujac) cables with calculations using the RHSD-RA Cable SGEMP analysis tool. The tool relies on CEPXS/ONBFP to perform radiation transport in a series of 1D slices through the cable, and then uses a Green function technique to evaluate the expected current drive on the center conductor. The data were obtained in 2003 as part of a Cabana verification and validation experiment using 1-D geometries, but were not evaluated until now. The agreement between data and model is not adequate unless gaps between the dielectric and outer conductor (ground) are assumed, and these gaps are large compared with what is believed to be in the actual cable.

10BASE5 Ethernet Cable & Vampire Tap

CERN Document Server

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.

Active optical cable for intrasatellite communications

Science.gov (United States)

Blasco, J.; Cano, D.; Navasquillo, O.; Esteban, M. A.

2017-11-01

DAS Photonics and Airbus Defence and Space (Spain) have been working for more than six years in the concept of an Active Optical Cable (AOC) for copper cable substitution. The main advantages that AOC offers are significant mass and size saving, better flexibility and routing of the cable and immunity to EMI.

Parallel monostrand stay cable bending fatigue

DEFF Research Database (Denmark)

Winkler, Jan Pawel

This dissertation investigates the bending fatigue response of high-strength steel monostrands and multistrand stay cables to cyclic transverse deformations. Increasing bridge stock numbers and a push for longer cable-supported span lengths have led to an increased number of reported incidents...... of damage and replacement of bridge stay cables due to wind and traffic-induced fatigue. The understanding of fatigue mechanisms in most steel structures is well established. However, in the case of cables composed of steel strands, many important aspects related with bending fatigue remain to be clarified...... associated with variable loading, and different testing procedures. As most of the contemporary stay cables are comprised of a number of individual highstrength steel monostrands, the research study started with an extensive experimental work on the fatigue response of a single monostrand to cyclic flexural...

Capacitor discharge process for welding braided cable

Science.gov (United States)

Wilson, Rick D.

1995-01-01

A capacitor discharge process for welding a braided cable formed from a plurality of individual cable strands to a solid metallic electrically conductive member comprises the steps of: (a) preparing the electrically conductive member for welding by bevelling one of its end portions while leaving an ignition projection extending outwardly from the apex of the bevel; (b) clamping the electrically conductive member in a cathode fixture; (c) connecting the electrically conductive member clamped in the cathode fixture to a capacitor bank capable of being charged to a preselected voltage value; (d) preparing the braided cable for welding by wrapping one of its end portions with a metallic sheet to form a retaining ring operable to maintain the individual strands of the braided cable in fixed position within the retaining ring; (e) clamping the braided cable and the retaining ring as a unit in an anode fixture so that the wrapped end portion of the braided cable faces the ignition projection of the electrically conductive member; and (f) moving the cathode fixture towards the anode fixture until the ignition projection of the electrically conductive member contacts the end portion of the braided cable thereby allowing the capacitor bank to discharge through the electrically conductive member and through the braided cable and causing the electrically conductive member to be welded to the braided cable via capacitor discharge action.

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.

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....

Air flow around suspended cables

Directory of Open Access Journals (Sweden)

Gołębiowska Irena

2017-01-01

Full Text Available The impact of wind on construction structures is essential issue in design and operation. In particular, the wind can cause the dengerous vibrations of slender structures with low rigidity, eg. vibrations of cables of suspension and cable-stayed bridges or high voltage transmision lines, thus understanding of wind flow around such constructions is significant. In the paper the results of the analysis of wind flow around the cables for different Reynolds number is presented. The analysed flow meets the Navier-Stokes and continuity equations. The circle and elipse section of the cable is analysed. The discusion of vorticity, drag and lift coefficients and cases due to different angle of wind flow action is presented. The boundary layer and its infuence on total flow is analysed.

Southwire's High Temperature Superconducting Cable Development - Summary Report

International Nuclear Information System (INIS)

Sinha, Uday; Lindsay, David

2005-01-01

Final technical report on Southwire HTS cable development program. Southwire started an HTS cable development program beginning early 1995 with a Co-operative Research and Development Agreement (CRADA) with Oak Ridge National Laboratory. The development task was to study the properties of HTS tapes, and construct hand wound 1-m cables to study the winding characteristics of the tapes. Within a short time several 1-m long cables were constructed and tested. A goal was established to construct a 30-m long, three single-phase cables suitable to carry 1250-Aac at 12.4 kV and power Southwire's two main manufacturing plants, machinery division, and part of the corporate headquarters building. Southwire chose to construct a cold dielectric (CD) design cable that has the advantage of shielding magnetic fields and suitable for carrying larger amounts of current for future applications. The CD design however, required a dielectric material that would be suitable at liquid nitrogen temperature. After considerable testing, a polymer based tape called ''Cryoflex'' was developed by Southwire for use as a cold dielectric. Southwire developed a HTS cable making facility for the winding of HTS and dielectric tapes. At the same time Southwire and ORNL developed at Oak Ridge a dielectric testing laboratory and a 5-m cable test bed. The HTS cable requires special terminations that connect cables at 77 K and high pressures (design pressure of 150 psi) with outside power at ambient temperature and pressure. Two types of terminations called Vacuum (T-1) and Pressure termination (T-2) were developed. The vacuum termination needed very high vacuum (10 -5 bar) and cold ceramic bushings that were expensive and unreliable. The modified pressure termination eliminated vacuum, utilize industrial bushings, reduced cost, and increased reliability. Two 5-m cables were designed and constructed at Southwire with the same rating as needed for the 30-m cables. The 5-m cables were tested successfully

Analysis of Electrical Coupling Parameters in Superconducting Cables

CERN Document Server

Bottura, L; Rosso, C

2003-01-01

The analysis of current distribution and redistribution in superconducting cables requires the knowledge of the electric coupling among strands, and in particular the interstrand resistance and inductance values. In practice both parameters can have wide variations in cables commonly used such as Rutherford cables for accelerators or Cable-in-Conduits for fusion and SMES magnets. In this paper we describe a model of a multi-stage twisted cable with arbitrary geometry that can be used to study the range of interstrand resistances and inductances that is associated with variations of geometry. These variations can be due to cabling or compaction effects. To describe the variations from the nominal geometry we have adopted a cable model that resembles to the physical process of cabling and compaction. The inductance calculation part of the model is validated by comparison to semi-analytical results, showing excellent accuracy and execution speed.

Characterization of fiber optic cables under large tensile loads

International Nuclear Information System (INIS)

Ogle, J.W.; Looney, L.D.; Peterson, R.T.

1984-01-01

Fiber optic cables designed for the Nevada Test Site (NTS) have to withstand an unusually harsh environment. Cables have been manufactured under a 6 year old DOE specification that has been slightly modified as the cable requirements are better understood. In order to better understand the cable properties a unique capability has been established at the NTS. Instrumentation has been developed to characterize the transmission properties of 1 km of fiber optic cable placed under a controlled tensile load up to 1500 lbs. The properties measured are cable tension, cable elongation, induced attenuation, attenuation vs. location, fiber strain, bandwidth, and ambient temperature. Preforming these measurements on cables from the two qualified NTS fiber optic cable manufacturers, Siecor and Andrew Corp., led to a new set of specifications

Neutron detector with gamma compensated cable

International Nuclear Information System (INIS)

Warren, H.D.

1975-01-01

An illustrative embodiment of the invention describes a technique for essentially eliminating the radiation induced background currents that are generated in the cable that connects an ''in-core'' neutron detector to an electrical terminal that is outside of the reactor's radiation field. This undesirable radiation-induced cable current is suppressed through an appropriate selection of conductor and cable sheath materials and sizes that generally satisfy the equation: Z/sub l/sup n/d/sub l/ = Z/sub s/sup m/d/sub s/ where Z is the atomic number of the material; d is a characteristic of the size of the cable component; m and/n have values between 1 and 5 to express the electron emissivity of the cable component from photoelectric and Compton effects; l represents the conductor; and s represents the sheath. Thus, the radiation-generated electrons emitted from the conductor and the oppositely-directed electrons emitted from the inner surface of the cable sheath are mutually cancelled if this equation is satisfied. A typical cable that does meet this criterion at low temperatures has a centrally disposed Zircaloy-2 inner conductor of 0.011 inch diameter, an annular insulation of magnesium oxide powder compacted to 100 percent density, and an Inconel sheath with an outside diameter of 0.062 inch and 0.011 inch wall thickness. (auth)

Numerical analysis of the stability of HTS power cable under fault current considering the gaps in the cable

International Nuclear Information System (INIS)

Fang, J.; Li, H.F.; Zhu, J.H.; Zhou, Z.N.; Li, Y.X.; Shen, Z.; Dong, D.L.; Yu, T.; Li, Z.M.; Qiu, M.

2013-01-01

Highlights: •The equivalent circuit equations and the heat balance equations were established. •The current distributions of the HTS cable under fault current were obtained. •The temperature curves of conductor layers under fault current were obtained. •The effect of the gap liquid nitrogen on the thermal characteristics was studied. -- Abstract: During the operation of a high temperature superconducting power cable in a real grid, the power cable can be impacted inevitably by large fault current. The study on current distribution and thermal characteristics in the cable under fault current is the foundation to analyze its stability. To analyze the operation situation of 110 kV/3 kA class superconducting cable under the fault current of 25 kA rms for 3 s, the equivalent circuit equations and heat balance equations were established. The current distribution curves and the temperature distribution curves were obtained. The liquid nitrogen which exists in the gaps of HTS cable was taken into consideration, the influence of gap liquid nitrogen on the thermal characteristics was investigated. The analysis results can be used to estimate the security and stability of the superconducting cable

Numerical analysis of the stability of HTS power cable under fault current considering the gaps in the cable

Energy Technology Data Exchange (ETDEWEB)

Fang, J., E-mail: fangseer@sina.com [School of Electrical Engineering, Beijing Jiaotong University, Beijing 100044 (China); Li, H.F. [School of Electrical Engineering, Beijing Jiaotong University, Beijing 100044 (China); Zhu, J.H.; Zhou, Z.N. [China Electric Power Research Institute, Beijing 100192 (China); Li, Y.X.; Shen, Z.; Dong, D.L.; Yu, T. [School of Electrical Engineering, Beijing Jiaotong University, Beijing 100044 (China); Li, Z.M.; Qiu, M. [China Electric Power Research Institute, Beijing 100192 (China)

2013-11-15

Highlights: •The equivalent circuit equations and the heat balance equations were established. •The current distributions of the HTS cable under fault current were obtained. •The temperature curves of conductor layers under fault current were obtained. •The effect of the gap liquid nitrogen on the thermal characteristics was studied. -- Abstract: During the operation of a high temperature superconducting power cable in a real grid, the power cable can be impacted inevitably by large fault current. The study on current distribution and thermal characteristics in the cable under fault current is the foundation to analyze its stability. To analyze the operation situation of 110 kV/3 kA class superconducting cable under the fault current of 25 kA{sub rms} for 3 s, the equivalent circuit equations and heat balance equations were established. The current distribution curves and the temperature distribution curves were obtained. The liquid nitrogen which exists in the gaps of HTS cable was taken into consideration, the influence of gap liquid nitrogen on the thermal characteristics was investigated. The analysis results can be used to estimate the security and stability of the superconducting cable.

Some considerations on special spacers with damping device for suppressing wake galloping in tandem cables of cable-stayed bridges; Heiretsu cable yo gensui kino tsuki supesa no gensui fuka tokusei ni kansuru 2,3 no kosatsu

Energy Technology Data Exchange (ETDEWEB)

Yoneda, M. [Kinki Univ., Higashi-Osaka, Osaka (Japan). Faculty of Science and Technology] Setouchi, H. [Kawada Industries Inc., Osaka (Japan)

1998-03-20

Cable vibration called wake galloping appears on cable-stayed bridges with parallel arranged cables and its suppression is an important problem. Various methods have been proposed for spacers with damping device for suppressing wake galloping in tandem cables of cable-stayed bridges. But, comparison of damping performances of various methods have not been discussed sufficiently. This paper deals with a type in which dampers are equipped on the midway of the tandem cables through the spacer jig and a type in which dampers are equipped on each surface of the tandem cables to generate shear deformation between them and circular spacer jig moiety and complex eigenvalue analyses are carried out on the two types with changing center spacing and diameters of the cables. The results clarify the relation between the structural damping characteristics and the cable spacing and the effect of torsional rigidity of the cables and also clarify of damping characteristics of the two types. 16 refs., 14 figs., 4 tabs.

Environmental assessment of submarine power cables

Energy Technology Data Exchange (ETDEWEB)

Isus, Daniel; Martinez, Juan D. [Grupo General Cable Sistemas, S.A., 08560-Manlleu, Barcelona (Spain); Arteche, Amaya; Del Rio, Carmen; Madina, Virginia [Tecnalia Research and Innovation, 20009 San Sebastian (Spain)

2011-03-15

Extensive analyses conducted by the European Community revealed that offshore wind energy have relatively benign effects on the marine environment by comparison to other forms of electric power generation [1]. However, the materials employed in offshore wind power farms suffer major changes to be confined to the marine environment at extreme conditions: saline medium, hydrostatic pressure... which can produce an important corrosion effect. This phenomenon can affect on the one hand, to the material from the structural viewpoint and on the other hand, to the marine environment. In this sense, to better understand the environmental impacts of generating electricity from offshore wind energy, this study evaluated the life cycle assessment for some new designs of submarine power cables developed by General Cable. To achieve this goal, three approaches have been carried out: leaching tests, eco-toxicity tests and Life Cycle Assessment (LCA) methodologies. All of them are aimed to obtaining quantitative data for environmental assessment of selected submarine cables. LCA is a method used to assess environmental aspects and potential impacts of a product or activity. LCA does not include financial and social factors, which means that the results of an LCA cannot exclusively form the basis for assessment of a product's sustainability. Leaching tests results allowed to conclude that pH of seawater did not significantly changed by the presence of submarine three-core cables. Although, it was slightly higher in case of broken cable, pH values were nearly equals. Concerning to the heavy metals which could migrate to the aquatic medium, there were significant differences in both scenarios. The leaching of zinc is the major environmental concern during undersea operation of undamaged cables whereas the fully sectioned three-core cable produced the migration of significant quantities of copper and iron apart from the zinc migrated from the galvanized steel. Thus, the tar

Environmental assessment of submarine power cables

International Nuclear Information System (INIS)

Isus, Daniel; Martinez, Juan D.; Arteche, Amaya; Del Rio, Carmen; Madina, Virginia

2011-03-01

Extensive analyses conducted by the European Community revealed that offshore wind energy have relatively benign effects on the marine environment by comparison to other forms of electric power generation [1]. However, the materials employed in offshore wind power farms suffer major changes to be confined to the marine environment at extreme conditions: saline medium, hydrostatic pressure... which can produce an important corrosion effect. This phenomenon can affect on the one hand, to the material from the structural viewpoint and on the other hand, to the marine environment. In this sense, to better understand the environmental impacts of generating electricity from offshore wind energy, this study evaluated the life cycle assessment for some new designs of submarine power cables developed by General Cable. To achieve this goal, three approaches have been carried out: leaching tests, eco-toxicity tests and Life Cycle Assessment (LCA) methodologies. All of them are aimed to obtaining quantitative data for environmental assessment of selected submarine cables. LCA is a method used to assess environmental aspects and potential impacts of a product or activity. LCA does not include financial and social factors, which means that the results of an LCA cannot exclusively form the basis for assessment of a product's sustainability. Leaching tests results allowed to conclude that pH of seawater did not significantly changed by the presence of submarine three-core cables. Although, it was slightly higher in case of broken cable, pH values were nearly equals. Concerning to the heavy metals which could migrate to the aquatic medium, there were significant differences in both scenarios. The leaching of zinc is the major environmental concern during undersea operation of undamaged cables whereas the fully sectioned three-core cable produced the migration of significant quantities of copper and iron apart from the zinc migrated from the galvanized steel. Thus, the tar

Study of the degradation of the insulation of HV cables with PVC insulation

International Nuclear Information System (INIS)

Quennehen, Pierre

2014-01-01

The observed decrease in the resistivity of the PVC insulation of some high voltage unipolar cables led to question their ability to perform their function. Provide answers concerning in particular the origin of the variation in resistivity and the impact on the dielectric strength were the objectives of this study. The characterizations were carried on cables withdrawn from service whose properties had changed during their use. Physico-chemical characterization (IR microscopy, UV spectroscopy, SEM - EDX and coulometry) showed that aging of the cable resulted from a mechanism of dehydro-chlorination. The presence of two modes of electric conduction in the material was observed: electronic conduction at a low temperature (≤ -10 C) and ionic conduction at room temperature and beyond. The presence of these two modes of conduction is consistent with the mechanism of dehydro-chlorination. In contrast to an Arrhenius law, artificial aging showed a threshold effect in the thermal activation of the mechanism at the origin of the resistivity drop. The dielectric strength of the cable has been confirmed by tests at voltages or temperatures well beyond the nominal values. Measurements of differential scanning calorimetry (DSC) showed occasional more or less pronounced over-heatings that correlate with the resistivity drops, and can therefore be considered as being at the origin of the observed evolutions. (author)

[Case-control study on cable-pin system in the treatment of olecranon fractures].

Science.gov (United States)

Ma, Hu-Jing; Shan, Lei; Zhou, Jun-Lin; Liu, Qing-He; Lu, Tie; Sun, Song

2012-05-01

To prospectively evaluate the clinical result of Cable-Pin system in the treatment of olecranon fractures and compare with tension band wiring (TBW) method. From March 2008 to June 2010,65 patients with olecranon fractures were divided into two groups: 32 patients in Cable-Pin group were treated with Cable-Pin system, including 18 males and 14 females, ranging in age from 21 to 69 years, with an average of (53.69 +/- 13.42) years; 33 patients in TBW group were treated with Kirschner tension bend, including 20 males and 13 females, ranging in age from 20 to 70 years, with an average of (53.18 +/- 13.36) years. The incision length, operation time, the amounts of hemoglobin after operation, fracture healing time, complications and HSS elbow scores were recorded and analyzed statistically. The follow-up period ranged from 12 to 24 months, with an average period of 18.4 months. There were statistical differences (PCable-Pin group. There was no statistical differences (P>0.05) in the length of incision (t= 0.416, P=0.679), operation time (t=0.816, P=0.417) and the postoperative amounts of hemoglobin (t=-0.553, P=0.294) between two groups. Cable-Pin system is an easy and reliable method for the treatment of olecranon fractures with less complications and better functions than TBW.

Non-linear stochastic response of a shallow cable

DEFF Research Database (Denmark)

Larsen, Jesper Winther; Nielsen, Søren R.K.

2004-01-01

The paper considers the stochastic response of geometrical non-linear shallow cables. Large rain-wind induced cable oscillations with non-linear interactions have been observed in many large cable stayed bridges during the last decades. The response of the cable is investigated for a reduced two...

Full-scale fire experiments on vertical horizontal cable trays

International Nuclear Information System (INIS)

Mangs, J.; Keski-Rahkonen, O.

1997-10-01

Two full-scale fire experiments on PVC cables used in nuclear power plants were carried out, one with cables in vertical position and one with cables in horizontal position. The vertical cable bundle, 3 m high, 300 mm wide and 30 mm thick, was attached to a steel cable ladder. The vertical bundle experiment was carried out in nearly free space with three walls near the cable ladder guiding air flow in order to stabilise flames. The horizontal cable experiment was carried out in a small room with five cable bundles attached to steel cable ladders. Three of the 2 m long cable bundles were located in an array, equally spaced above each other near one long side of the room and two correspondingly near the opposite long side. The vertical cable bundle was ignited with a small propane gas burner beneath the lower edge of the bundle. The horizontal cable bundles were ignited with a small propane burner beneath the lowest bundle in an array of three bundles. Rate of heat release by means of oxygen consumption calorimetry, mass change, CO 2 , CO and smoke production rate and gas, wall and cable surface temperatures were measured as a function of time, as well as time to sprinkler operation and failure of test voltage in cables. Additionally, the minimum rate of heat release needed to ignite the bundle was determined. This paper concentrates on describing and recording the experimental set-up and the data obtained. (orig.)

Study on the Mechanical Properties of Stay Cable HDPE Sheathing Fatigue in Dynamic Bridge Environments

Directory of Open Access Journals (Sweden)

Danhui Dan

2015-08-01

Full Text Available As the main force-bearing component of a cable-stayed bridge, a durable stay cable is paramount to the safety and durability of the entire bridge. High-density polyethylene (HDPE sheathing is the main protective component of a stay cable and is the key to insuring cable durability. To address the issue of HDPE sheathing fracture on service, strain level data for in-service, HDPE bridge cable sheathing was used in this study as the basis for HDPE material aging and fatigue testing. A fatigue yield phenomenon with a yield platform on the hysteresis curve of the fatigue cycles is observed by the fatigue test. The parameters to describe this phenomenon are proposed and defined in this paper. A preliminary examination of the relationship between these parameters and the factors, such as the number of cycles, the strain amplitude, and strain rate, are presented. Based on the results obtained, it is suggested that the condition of fatigue yield of HDPE sheathing be defined as the fatigue durability limit state for the purposes of durability design, assessment, and protection of cable-stayed bridges.

Design of anti-theft/cable cut real time alert system for copper cable using microcontroller and GSM technology

Science.gov (United States)

Lim, E. K.; Norizan, M. N.; Mohamad, I. S.; Yasin, M. N. M.; Murad, S. A. Z.; Baharum, N. A.; Jamalullail, N.

2017-09-01

This paper presents the design of anti-theft/cable cut real time alert system using microcontroller and GSM technology. The detection part is using the electrical circuit wire connection in detecting the voltage drop of the cable inside the microcontroller digital input port. The GSM wireless modem is used to send the location of cable cut directly to the authority mobile phone. Microcontroller SK40C with Microchip PIC16F887 is used as a controller to control the wireless modem and also the detection device. The device is able to detect and display the location of the cable cut on the LCD display besides of and sending out the location of the cable break to the authority mobile phone wirelessly via SMS.

External heating of electrical cables and auto-ignition investigation

Energy Technology Data Exchange (ETDEWEB)

Courty, L., E-mail: leo.courty@univ-orleans.fr [Univ. Orleans, PRISME EA 4229, 63 Avenue de Lattre de Tassigny, 18020 Bourges (France); Garo, J.P. [Institut P’, UPR 3346 CNRS, ENSMA, Univ. Poitiers, 1 Av. Clément Ader, Téléport 2, BP 40109, 86961 Futuroscope Chasseneuil (France)

2017-01-05

Highlights: • Electrical cables pyrolysis and flammability have been studied. • Two different experimental setups were used to study cables mass loss and flammability. • A 1-D thermal model for cables mass loss and temperature is proposed. • Spontaneous and piloted ignitions have been investigated. - Abstract: 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.

External heating of electrical cables and auto-ignition investigation

International Nuclear Information System (INIS)

Courty, L.; Garo, J.P.

2017-01-01

Highlights: • Electrical cables pyrolysis and flammability have been studied. • Two different experimental setups were used to study cables mass loss and flammability. • A 1-D thermal model for cables mass loss and temperature is proposed. • Spontaneous and piloted ignitions have been investigated. - Abstract: 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.

High voltage pulsed cable design: a practical example

International Nuclear Information System (INIS)

Kewish, R.W. Jr.; Boicourt, G.P.

1979-01-01

The design of optimum high voltage pulse cable is difficult because very little emperical data are available on performance in pulsed applications. This paper follows the design and testing of one high voltage pulse cable, 40/100 trigger cable. The design was based on an unproven theory and the impressive outcome lends support to the theory. The theory is outlined and it is shown that there exists an inductance which gives a cable of minimum size for a given maximum stress. Test results on cable manufactured according to the design are presented and compared with the test results on the cable that 40/100 replaces

High voltage pulsed cable design: a practical example

Energy Technology Data Exchange (ETDEWEB)

Kewish, R.W. Jr.; Boicourt, G.P.

1979-01-01

The design of optimum high voltage pulse cable is difficult because very little emperical data are available on performance in pulsed applications. This paper follows the design and testing of one high voltage pulse cable, 40/100 trigger cable. The design was based on an unproven theory and the impressive outcome lends support to the theory. The theory is outlined and it is shown that there exists an inductance which gives a cable of minimum size for a given maximum stress. Test results on cable manufactured according to the design are presented and compared with the test results on the cable that 40/100 replaces.

Management of displaced inferior patellar pole fractures with modified tension band technique combined with cable cerclage using Cable Grip System.

Science.gov (United States)

Yang, Xu; Wu, Qinfen; Lai, Chin-Hui; Wang, Xin

2017-10-01

We present a modified tension band technique combined with cable cerclage using Cable Grip System for the treatment of displaced inferior patellar pole fractures and report the knee functional outcome. The patients who had had operative treatment of a displaced inferior patellar pole fracture (AO/OTA 34-A1) between December 2013 and December 2015 were studied retrospectively. Eleven consecutive patients had had open reduction and internal fixation with the modified technique using Cable Grip System, of whom, five males and six females with an average age of 60.9 years (range, 29-81 years). All fractures occurred from direct fall onto the knee. The average time from injury to surgery was 6.1days (range, 2-12days). The range of motion (ROM) was measured in degrees by goniometry at postoperative intervals of 1, 2, 4, 12, and 48 weeks; Knee function was evaluated using the Rasmussen scores at final follow-up. No patients had nonunion, loss of reduction, migration of wire, irritation from the implant and fixation breakage during the follow-up period. Recovery of ROM was achieved at 12 weeks, with the average ROM at 1 week was 72° (range, 65°-78°), 86.4° (range, 78°-92°) at 2 weeks, 115.5° (range, 103°-122°) at 4 weeks, 129.6° (range, 122°-133°) at 12 weeks, 134.5° (range, 129°-139°) at 48 weeks after the operation. Concerning the knee function outcome assessment, all patients showed excellent results at final follow-up. The average Rasmussen scores was 27.9 out of 30 (range, 27-29). The modified tension band technique combined with cable cerclage using Cable Grip System for displaced inferior patellar pole fractures can provide stable fixation with excellent results in knee function, allows for immediate mobilization and early weight-bearing, which is a simple and valuable technique in routine clinical practice. Copyright © 2017 Elsevier Ltd. All rights reserved.

47 CFR 76.802 - Disposition of cable home wiring.

Science.gov (United States)

2010-10-01

... 47 Telecommunication 4 2010-10-01 2010-10-01 false Disposition of cable home wiring. 76.802... MULTICHANNEL VIDEO AND CABLE TELEVISION SERVICE Cable Inside Wiring § 76.802 Disposition of cable home wiring. (a)(1) Upon voluntary termination of cable service by a subscriber in a single unit installation, a...

Current distribution in Cable-In-Conduit Conductors

International Nuclear Information System (INIS)

Ferri, M.A.

1994-05-01

A numerical study of the current distribution in Cable-In-Conduit Conductors (CICC's) experiencing linearly ramping transport currents and transverse magnetic fields was conducted for both infinitely long, periodic cables and finite length cables terminated in low resistance joints. The goal of the study was to gain insight into the phenomenon known as Ramp Rate Limitation, an as yet unexplained correspondence between maximum attainable current and the ramp time taken to reach that current in CICC superconducting magnets. A discrete geometric model of a 27 strand multiply twisted CICC was developed to effectively represent the flux linkages, mutual inductances, and resistive contact points between the strands of an experimentally tested cable. The results of the numerical study showed that for fully periodic cables, the current imbalances due to ramping magnetic fields and ramping transport currents are negligible in the range of experimentally explored operating conditions. For finite length, joint terminated cables, however, significant imbalances can exist. Unfortunately, quantitative results are limited by a lack of knowledge of the transverse resistance between strands in the joints. Nonetheless, general results are presented showing the dependency of the imbalance on cable length, ramp time, and joint resistance for both ramping transverse magnet fields and ramping transport currents. At the conclusion of the study, it is suggested that calculated current imbalances in a finite length cable could cause certain strands to prematurely ''quench'' -- become non-superconducting --thus leading to an instability for the entire cable. This numerically predicted ''current imbalance instability'' is compared to the experimentally observed Ramp Rate Limitation for the 27 strand CICC sample

submitter On Roebel Cable Geometry for Accelerator Magnet

CERN Document Server

Fleiter, J; Ballarino, A

2016-01-01

Roebel-type cables made of a ReBCO conductor are potential candidates for high-field accelerator magnets. The necessity to promote a large effective transverse section in a Roebel cable to avoid local overstress leading to degradation in electrical performance has been recently addressed. In this paper, a new geometry of meander tapes for a Roebel cable that enhances both the transverse effective section and the current margin at crossing segments is discussed. As Roebel cables are bent at the coil ends, the modulation of the bending radius of strands along the cable pitch leads to a shift of the strands with respect to each other. The shift magnitude is analytically investigated in this paper as a function of both cable features and coil geometry. Finally, the minimum transposition pitch of Roebel cables is determined on the basis of coil characteristics.

Wire in the Cable-Driven System of Surgical Robot

Science.gov (United States)

Wang, X. F.; Lv, N.; Mu, H. Z.; Xue, L. J.

2017-07-01

During the evolution of the surgical robot, cable plays an important role. It translates motion and force precisely from surgeon’s hand to the tool’s tips. In the paper, the vertical wires, the composition of cable, are mathematically modeled from a geometric point of view. The cable structure and tension are analyzed according to the characteristics of wire screw twist. The structural equations of the wires in different positions are derived for both non-bent cable and bent cable, respectively. The bending moment formula of bent cable is also obtained. This will help researchers find suitable cable and design more matched pulley.

Comparison of advanced high power underground cable designs

International Nuclear Information System (INIS)

Erb, J.; Heinz, W.; Hofmann, A.; Koefler, H.J.; Komarek, P.; Maurer, W.; Nahar, A.

1975-09-01

In this paper, advanced high power underground cable designs are compared in the light of available literature, of reports and information supplied by participating industries (AEG, BICC, CGE, Pirelli, Siemens), spontaneous contributions by EdF, France, BBC and Felten and Guilleaume Kabelwerke A.G., Germany, and Hitachi, Furukawa, Fujikura and Sumitomo, Japan, and earlier studies carried out at German public research centres. The study covers cables with forced cooling by oil or water, SF 6 -cables, polyethylene cables, cryoresistive and superconducting cables. (orig.) [de

An industrial cabling machine for the SSC

International Nuclear Information System (INIS)

Royet, J.; Armer, R.; Hannaford, R.; Scanlan, R.

1989-02-01

The SSC project will need the manufacturing of some 25,000 kilometers of keystoned flat cable. The technical specifications of the various cables to be produced are the result of five years of research and development work at LBL. An experimental cable machine was built and run in the laboratory; many improvements were implemented and tested. Semi-industrial production of the various cables was performed, and the resulting cables were used and tested in the one-meter model magnets and 17.5 meter dipole prototypes. From these experiments an industrial cabler specification was generated and used for an international RFQ. The winner of the contract is Dour Metal, a Belgium company that built the first industrial prototype which is now in a production line at New England Electric Wire Company. In this paper we describe the main characteristics of the machine and give the first industrial production results of superconducting keystoned cable for the SSC project. 4 refs

Influence of water trees on breakdown voltage of polymeric cables insulations

Energy Technology Data Exchange (ETDEWEB)

Stancu, Cristina [INCDIE ICPE CA, Bucharest (Romania); Notingher, Petru V.; Plopeanu, Mihai Gabriel [Politehnica University of Bucharest, Bucharest (Romania)

2011-07-01

In a previous paper was shown that water trees development modifies considerably the electric field repartition, which increases significantly in the vicinity of treed areas. In order to find the water trees influence on the breakdown voltage, in the present paper, an experimental study on model cables insulated with low density polyethylene is done. In insulation samples, water trees with various dimensions and densities were developed. For the reduction of the test duration, an electric field with a higher frequency (3-5 kHz) was used. For breakdown voltage measurement an automatic setup was realized. For each value of the ageing time the dimensions and densities of water trees and breakdown voltage were measured and the dependency of the breakdown voltage with these quantities were analysed. The results show a significant reduction of the breakdown voltage of treed cables insulations compared to un-treed ones. Key words: polyethylene, water treeing, electric field, breakdown, power cables.

47 CFR 76.111 - Cable sports blackout.

Science.gov (United States)

2010-10-01

... 47 Telecommunication 4 2010-10-01 2010-10-01 false Cable sports blackout. 76.111 Section 76.111... CABLE TELEVISION SERVICE Network Non-duplication Protection, Syndicated Exclusivity and Sports Blackout § 76.111 Cable sports blackout. (a) No community unit located in whole or in part within the specified...

Dynamic model and workspace analysis of novel incompletely restrained cable-suspension swing system driven by two cables

Directory of Open Access Journals (Sweden)

Naige Wang

2017-03-01

Full Text Available The incompletely restrained cable-suspension swing system driven by two cables is introduced in this article. Based on wrench of forces theory and Lagrange’s equation of first kind, the static and dynamics models of incompletely restrained cable-suspension swing system driven by two cables are established, respectively. In order to obtain an intuitive understanding of the trajectory analysis, a dynamics model consisting of governing equation and geometric constraint conditions which is a set of the mixed differential-algebraic equation in mathematics is established. A typical feedback controller and an inverse model were set up to estimate the driving function. The effective workspace, which is used to guarantee an efficient swing process, mostly depends on the geometrical shape rather than the volume itself which was calculated by trajectory analysis. In order to estimate system features and ensure a limited range of tension in underconstrained spatial cable system, the probable location of unbalanced loading was evaluated by pointwise evaluation techniques during normal work.

Configuration Synthesis for Fully Restrained 7-Cable-Driven Manipulators

Directory of Open Access Journals (Sweden)

Xiaoqiang Tang

2012-10-01

Full Text Available Cable distribution plays a vital role in Cable Driven Parallel Manipulators (CDPMs regarding tension and workspace quality, especially in fully restrained CDPMs. This paper focuses on three typical configurations of fully restrained CDPMs with 7 cables in order to introduce an approach for configuration synthesis. Firstly, the kinematic models of three types of CDPMs with 7 cables are set up. Then, in order to evaluate workspace quality, two new indices are proposed by using tensions along each cable, which are the All Cable Tension Distribution Index (ACTDI and Global Tension Distribution Index (GTDI. Next, the three types of CDPMs with 7 cables are analysed with the two indices. At the end, according to different performance requirements, the configurations of cable distribution are discussed and selected.

Commercialization of Medium Voltage HTS Triax TM Cable Systems

Energy Technology Data Exchange (ETDEWEB)

Knoll, David

2012-12-31

The original project scope that was established in 2007 aimed to install a 1,700 meter (1.1 mile) medium voltage HTS Triax{TM} cable system into the utility grid in New Orleans, LA. In 2010, however, the utility partner withdrew from the project, so the 1,700 meter cable installation was cancelled and the scope of work was reduced. The work then concentrated on the specific barriers to commercialization of HTS cable technology. The modified scope included long-length HTS cable design and testing, high voltage factory test development, optimized cooling system development, and HTS cable life-cycle analysis. In 2012, Southwire again analyzed the market for HTS cables and deemed the near term market acceptance to be low. The scope of work was further reduced to the completion of tasks already started and to testing of the existing HTS cable system in Columbus, OH. The work completed under the project included: • Long-length cable modeling and analysis • HTS wire evaluation and testing • Cable testing for AC losses • Optimized cooling system design • Life cycle testing of the HTS cable in Columbus, OH • Project management. The 200 meter long HTS Triax{TM} cable in Columbus, OH was incorporated into the project under the initial scope changes as a test bed for life cycle testing as well as the site for an optimized HTS cable cooling system. The Columbus cable utilizes the HTS TriaxTM design, so it provided an economical tool for these of the project tasks.

Electrical cabling system associated at a nuclear reactor

International Nuclear Information System (INIS)

Dejeux, P.; Desfontaines, G.

1988-01-01

This cabling system for an electrical device in a nuclear reactor comprises at least a first cable issued of the device, a second cable comprising a first portion, a second portion and a third portion joining the second by a multiple quick fitting connector capable to connect at least ten second portions at ten other third portions of the second cable [fr

Versatile cable handling mechanisms for remote operator control

Energy Technology Data Exchange (ETDEWEB)

Collie, A.A.; White, T.S.; Christopher, M.D.; Hewer, N.D. [Portech Ltd., Portsmouth (United Kingdom)

1996-12-31

This paper describes a system of cable management for keeping the umbilical cables of remote operating vehicles and manipulators tidy and contained without direct intervention by operators. Two distinct types of winding mechanism have been designed. One mechanism is a fixed reel type where the cable is wound onto the reel by a rotating bail arm. The other mechanism consists of a pair of curved belts held against each other between which cable is passed. The complete system includes tension measuring and slack loop take-up devices. The whole system is controlled by a servo system in conjunction with a PC based visual graphic environment which allows a variety of mechanisms to be built up into a system able to handle up to four umbilical cables simultaneously. The control system provides additional tension sensors and cable odometers connected to the control system so that the operator has immediate perception of all the cable parameters, and by defining rules, can set up a variety of alarm situations. (Author).

Versatile cable handling mechanisms for remote operator control

International Nuclear Information System (INIS)

Collie, A.A.; White, T.S.; Christopher, M.D.; Hewer, N.D.

1996-01-01

This paper describes a system of cable management for keeping the umbilical cables of remote operating vehicles and manipulators tidy and contained without direct intervention by operators. Two distinct types of winding mechanism have been designed. One mechanism is a fixed reel type where the cable is wound onto the reel by a rotating bail arm. The other mechanism consists of a pair of curved belts held against each other between which cable is passed. The complete system includes tension measuring and slack loop take-up devices. The whole system is controlled by a servo system in conjunction with a PC based visual graphic environment which allows a variety of mechanisms to be built up into a system able to handle up to four umbilical cables simultaneously. The control system provides additional tension sensors and cable odometers connected to the control system so that the operator has immediate perception of all the cable parameters, and by defining rules, can set up a variety of alarm situations. (Author)

Versatile cable handling mechanisms for remote operator control

International Nuclear Information System (INIS)

Collie, A.A.; White, T.S.; Christopher, M.D.; Hewer, N.D.

1996-01-01

This paper describes a system of cable management for keeping the umbilical cables of remote operating vehicles and manipulators tidy and contained without direct intervention by operators. Two distinct types of winding mechanism have been designed. One mechanism is a fixed reel type where the cable is wound onto the reel by a rotating bail arm. The other mechanism consists of a pair of curved belts held against each other, between which cable is passed. The complete system includes tension measuring and slack loop take-up devices. The whole system is controlled by a servo system in conjunction with a PC based visual graphic environment which allows a variety of mechanisms to be built up into a system able to handle up to four umbilical cables simultaneously. The control system provides additional tension sensors and cable odometers connected to the control system so that the operator has immediate perception of all the cable parameters, and by defining rules, can set up a variety of alarm situations. (UK)

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.

Elasticity and mechanical advantage in cables and ropes

International Nuclear Information System (INIS)

O'Shea, M J

2007-01-01

The conditions under which one can gain mechanical advantage by pulling with a force F perpendicular to a cable (or rope) that is fixed at both ends are examined. While this is a commonly discussed example in introductory physics classes, its solution in terms of fundamental properties of the cable requires one to model the elasticity of the cable. This solution has several complex and interesting features, e.g. a large increase in the tension in the cable may occur upon application of F if (i) F lies in a certain range and (ii) the initial tension T 1 in the cable (before F is applied) satisfies T 1 < 0.0340 κ. Here, κ is the spring constant of a unit length of the cable. For steel cables and cables composed of other materials such as carbon nanorods where the elasticity is low, significant increases in tension are possible. Examples involving walking a tightrope and attempting to increase the tension in a rope hauling a load are considered. Two programs to solve the equations of this work are available in the electronic version of this journal

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.

Comparison of programmed and cabled re-entrance systems. Elaboration of cabled re-entrance system for a CII 90.40; Comparaison des systemes de reentrance programmes et cables. Realisation d'un systeme de reentrance cable pour un CII 90.40

Energy Technology Data Exchange (ETDEWEB)

Perraudeau, Jean

1976-11-26

The objective of this research thesis is to study problems related to re-entrance, and, more particularly, to study a re-entrance system for a CII 90.40 computer. Such a system can be realised under a programmed or cabled form, and both approaches are described and compared. A generalisation of this comparison is briefly proposed. As the computer already possesses a programmed re-entrance system, the author focuses on the study of the cabled re-entrance system which results in an improvement of performance and possibilities provided by this computer, particularly for its use in real time. The design, realisation and development of such a cabled system are reported. A first part reports a theoretical study on re-entrance (definition, problems, applications), a presentation of the computer, a description of the programmed re-entrance system, a presentation of the principle of the chosen cabled re-entrance system, a definition of the structure and operating mode of the cabled pile and a description of its various components, and a flowchart analysis of function execution. The second part reports the practical realisation: definition, technological overview, technology used in the cabled pile, sequencing and multiplexing principle, impulse transmission, logical layouts, and circuit adjustments. The third part presents practical example. An assessment and perspectives are finally discussed.

Behaviour of electrical cables under fire conditions

International Nuclear Information System (INIS)

Bertrand, R.; Chaussard, M.; Gonzalez, R.; Lacoue, J.; Mattei, J.M.; Such, J.M.

2002-01-01

A Fire Probabilistic Safety Assessment - called the Fire PSA - is being carried out by the French Institute of Radiological Protection and Nuclear Safety (IPSN) to be used in the framework of the safety assessment of operating 900 MWe PWRs. The aim of this study is to evaluate the core damage conditional probability which could result from a fire. A fire can induce unavailability of safety equipment, notably damaging electrical cables introducing a significant risk contributor. The purpose of this paper is to present the electrical cable fire tests carried out by IPSN to identify the failure modes and to determine the cable damage criteria. The impact of each kind of cable failure mode and the methodology used to estimate the conditional probability of a failure mode when cable damage occurred is also discussed. (orig.) [de

Superconducting power cables in Denmark - a case study

DEFF Research Database (Denmark)

Østergaard, Jacob

1997-01-01

A case study of a 450 MVA, 132 kV high temperature superconducting (HTS) power transmission cable has been carried out. In the study, a superconducting cable system is compared to a conventional cable system which is under construction for an actual transmission line in the Danish grid. The study...... that HTS cables will be less expensive for high power ratings, have lower losses for lines with a high load, and have a reduced reactive power production. The use of superconducting cables in Denmark accommodate plans by the Danish utility to make a substantial conversion of overhead lines to underground...

46 CFR 111.12-9 - Generator cables.

Science.gov (United States)

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Generator cables. 111.12-9 Section 111.12-9 Shipping... REQUIREMENTS Generator Construction and Circuits § 111.12-9 Generator cables. (a) The current-carrying capacity of generator cables must not be: (1) Less than 115 percent of the continuous generator rating; or (2...

Development of scaling rules for Rutherford type superconducting cables

International Nuclear Information System (INIS)

Royet, J.M.; Scanlan, R.M.

1991-01-01

During the R and D phase of the Superconducting Supercollider (SSC) program, LBL was responsible for establishing the parameters for cables used in SSC dipole and quadrupole magnets. In addition, LBL has collaborated with Fermi National Accelerator Laboratory on the design and fabrication of a new cable for use in the Low Beta Quadrupoles. As a result of the development work on these and other cables, we have arrived a set of scaling rules which provide guidelines for choosing the parameters for a wide range of superconducting cables. These parameters include strand size, strand number, keystone angle, percent compaction, cable pitch and compacted cable dimensions. In addition, we have defined the tolerance ranges for the key cable manufacturing parameters such as mandrel size and shape, strand tension, and Turkshead temperature control. In this paper, the authors present the results on cables ranging from 8 strands to 36 strands of 0.65mm wire and from 8 strands to 30 strands of 0.8mm wire. The authors use these results to demonstrate the application of the scaling rules for Rutherford-type cable

Development of scaling rules for Rutherford type superconducting cables

International Nuclear Information System (INIS)

Royet, J.M.; Scanlan, R.M.

1990-09-01

During the R ampersand D phase of the Superconducting Supercollider (SSC) program, LBL was responsible for establishing the parameters for cables used in SSC dipole and quadrupole magnets. In addition, the design and fabrication of a new cable for use in the Low Beta Quadrupoles. As a result of the development work on these and other cables, we have arrived a set of scaling rules which provide guidelines for choosing the parameters for a wide range of superconducting cables. These parameters include strand size, strand number, keystone angle, percent compaction, cable pitch and compacted cable dimensions. In addition, we have defined the tolerance ranges for the key cable manufacturing parameters such as mandrel size and shape, stand tension, and Turkshead temperature control. In this paper, we present the results on cables ranging from 8 strands to 36 strands of 0.65mm wire and from 8 strands to 30 strands of 0.8mm wire. We use these results to demonstrate the application of the scaling rules for Rutherford-type cable

Data Base On Cables And Connectors

Science.gov (United States)

Bowen, Arlen R.; Oliver, John D.

1995-01-01

Report describes Connector Adapter Cable Information Data Base (CONNAID) computer program, managing data base containing necessary information concerning electrical connectors, breakout boxes, adapter cables, backshells, and pertinent torque specifications for engineering project.

Manufacturing experience for the LHC inner triplet quadrupole cables

CERN Document Server

Scanlan, R M; Bossert, R; Kerby, J S; Ghosh, A K; Boivin, M; Roy, T

2002-01-01

The design for the U.S. LHC Inner Triplet Quadrupole magnet requires a 37 strand (inner layer) and a 46 strand (outer layer) cable. This represents the largest number of strands attempted to date for a production quantity of Rutherford-type cable. The cable parameters were optimized during the production of a series of short prototype magnets produced at FNAL. These optimization studies focused on critical current degradation, dimensional control, coil winding, and interstrand resistance. After the R&D phase was complete, the technology was transferred to NEEW and a new cabling machine was installed to produce these cables. At present, about 60 unit lengths, out of 90 required for the entire production series of magnets, have been completed for each type of cable. The manufacturing experience with these challenging cables will be reported. Finally, the implications for even larger cables, with more strands, will be discussed. (8 refs).

Cable Television in Sedalia, Missouri.

Science.gov (United States)

Lamkin, Kathryn Janel

A field study was conducted of the status of cable television in Sedalia, Missouri. Based on interviews of city council members and staff members of Cablevision, the Sedalia cable franchise holder, the following issues were investigated: (1) subscription rates; (2) franchise negotiations; (3) quality of existing services; and (4) possible…

Development of a single-phase 30 m HTS power cable

Science.gov (United States)

Cho, Jeonwook; Bae, Joon-Han; Kim, Hae-Jong; Sim, Ki-Deok; Kim, Seokho; Jang, Hyun-Man; Lee, Chang-Young; Kim, Dong-Wook

2006-05-01

HTS power transmission cables appear to be the replacement and retrofitting of underground cables in urban areas and HTS power transmission cable offers a number of technical and economic merits compared to the normal conductor cable system. A 30 m long, single-phase 22.9 kV class HTS power transmission cable system has been developed by Korea Electrotechnology Research Institute (KERI), LS Cable Ltd., and Korea Institute of Machinery and Materials (KIMM), which is one of the 21st century frontier project in Korea since 2001. The HTS power cable has been developed, cooled down and tested to obtain realistic thermal and electrical data on HTS power cable system. The evaluation results clarified such good performance of HTS cable that DC critical current of the HTS cable was 3.6 kA and AC loss was 0.98 W/m at 1260 Arms and shield current was 1000 Arms. These results proved the basic properties for 22.9 kV HTS power cable. As a next step, we have been developing a 30 m, three-phase 22.9 kV, 50 MV A HTS power cable system and long term evaluation is in progress now.

High power cable with internal water cooling 400 kV

Science.gov (United States)

Rasquin, W.; Harjes, B.

1982-08-01

Due to the concentration of electricity production in large power plants, the need of higher power transmissions, and the protection of environment, developement of a 400 kV water cooled cable in the power range of 1 to 5 GVA was undertaken. The fabrication and testing of equipment, engineering of cable components, fabrication of a test cable, development of cable terminal laboratory, testing of test cable, field testing of test cable, fabrication of industrial cable laboratory, testing of industrial cable, field testing of industrial cable, and system analysis for optimization were prepared. The field testing was impossible to realize. However, it is proved that a cable consisting of an internal stainless steel water cooled tube, covered by stranded copper profiles, insulated with heavy high quality paper, and protected by an aluminum cover can be produced, withstand tests accordingly to IEC/VDE recommendations, and is able to fulfill all exploitation conditions.

Full-scale horizontal cable-tray tests: Fire-propagation characteristics

International Nuclear Information System (INIS)

Anon.

1991-01-01

At the Fermi National Accelerator Center (Fermilab), as at any high-energy physics laboratory, the experimental program depends on complex arrays of equipment that require years to assemble and place in service. These equipment arrays are typically located in enclosed tunnels or experimental halls and could be destroyed by rapidly propagating, uncontrolled fire. Cable trays, both vertical and horizontal, are an integral and ubiquitous component of these installations. Concurrently, throughout industry and within the professional fire-fighting community, there has been concern over the flammability and fire propagation characteristics of electrical cables in open cable trays. While some information was available concerning fire propagation in vertical cable trays, little was known about fires in horizontal cable trays. In view of the potential for loss of equipment and facilities, not to mention the programmatic impact of a fire, Fermilab initiated a program of full-scale, horizontal cable-tray fire tests to determine the flammability and rate of horizontal fire propagation in cable-tray configurations and cable mixed typical of those existing in underground tunnel enclosures and support buildings as Fermilab. This series of tests addressed the effects of ventilation rates and cable-tray fill, fire-fighting techniques, and the effectiveness and value of automatic sprinklers, smoke detection, and cable-coating fire barriers in detecting, controlling, or extinguishing a cable-tray fire. Detailed descriptions of each fire test, including sketches of cable-tray configuration and contents, instrumentation, ventilation rates, Fermilab Fire Department personnel observations, photographs, and graphs of thermocouple readings are available in a report of these tests prepared by the Fermilab Safety Section

CSNS control cable information management system based on web

International Nuclear Information System (INIS)

Lu Huihui; Wang Chunhong; Li Luofeng; Liu Zhengtong; Lei Bifeng

2014-01-01

This paper presents an approach to data modeling a great number of control devices and cables with complicated relations of CSNS (China Spallation Neutron Source). The CSNS accelerator control cable database was created using MySQL, and the control cable information management system based on Web was further built. During the development of the database, the design idea of IRMIS database was studied. and the actual situation of CSNS accelerator control cables was investigated. The control cable database model fitting the requirements was designed. This system is of great convenience to manage and maintain CSNS control devices and cables in the future. (authors)

Cable-to-post attachments for use in non-proprietary high-tension cable median barrier - phase II.

Science.gov (United States)

2016-03-24

The objective of this study was to reevaluate and improve the existing cable-to-post attachment hardware that is utilized : in the non-proprietary cable barrier being developed at MwRSF. The study focused on redesigning the bolted, tabbed : bracket (...

Practical cable tension adjustment based upon the satisfaction concept of bridge designers; Sekkeisha no manzokudo wo koryo shita fuzzy cable choryoku choseiho

Energy Technology Data Exchange (ETDEWEB)

Kaneyoshi, M.; Tanaka, H. [Hitachi Zosen, Tokyo (Japan)] Furuta, H. [Kansai Univ., Osaka (Japan)

1998-07-21

Cable tension adjustment of bridge beam of cable stayed bridge and so forth that uses cable as a structural element is classified into (1) pre-stress adjustment of cable at design level, (2) slim adjustment required at erection level. The former deals with the structurally high dimensional statically indeterminate structures like cable-stayed bridges and is a process for carrying out economical design by making the stress resultant of main girder small due to the introduction of appropriate pre-stress stress on this cable. The later is the process of getting rid off the errors caused in cable tension and camber of girder and tower regarding various errors such as design, fabrication and erection errors. The authors developed analysis method using fuzzy regression analysis and this has been applied in number of practical bridges. In this research, much more practical method is developed where the aspire of designer can be introduced easily by applying the satisfaction concept. By using this, pre-stress adjustment and shim adjustment of cable can be possible in a practical way. 9 refs., 7 figs., 8 tabs.

Losses in armoured three-phase submarine cables

DEFF Research Database (Denmark)

Ebdrup, Thomas; Silva, Filipe Miguel Faria da; Bak, Claus Leth

2014-01-01

The number of offshore wind farms will keep increasing in the future as a part of the shift towards a CO2 free energy production. The energy harvested from the wind farm must be brought to shore, which is often done by using a three-phase armoured submarine power cable. The use of an armour...... increases the losses in armoured cables compared to unarmoured cables. In this paper a thorough state of the art analysis is conducted on armour losses in three-phase armoured submarine power cables. The analysis shows that the IEC 60287-1-1 standard overestimates the armour losses which lead...... to the installation of cables with excessive phase conductor cross section. This paper also presents an example of the potential economic benefits of having a better knowledge of the losses introduced by the armour....

Prevention of cable fires in nuclear power plants

International Nuclear Information System (INIS)

Murota, George; Yajima, Kazuo

1979-01-01

Nuclear power generation is indispensable to secure required electric power, therefore double or triple safety measures are necessary to prevent serious accidents absolutely. As for the countermeasures to cable fires, interest grew rapidly with the fire in Browns Ferry Power Station in USA in 1975 as the turning point, because multi-strand grouped cables caused to promote the spread of fire. In Japan, also the fire prevention measures for wires and cables were more strengthened, and the measures for preventing the spread of cable fires with the agent preventing the spread of fires have occupied the important position. When multi-strand cables are ignited by some cause, the fire spreads with very large combustion force along wirings to other rooms and installations, and electric systems are broken down. The harmful corrosive gas generated from the burning coating materials of cables diffuses very quickly. In nuclear power stations, the cables which are very hard to burn are adopted, fire prevention sections are established positively, the fire-resisting capability of fire prevention barriers is reviewed, and fire-resisting and smoke-preventing treatments are applied to the parts where cables penetrate walls, floors or ceilings. The paint and the sealing material which prevent the spread of fires are introduced. (Kako, I.)

Loss and Inductance Investigation in Superconducting Cable Conductors

DEFF Research Database (Denmark)

Olsen, Søren Krüger; Tønnesen, Ole; Træholt, Chresten

1999-01-01

An important parameter in the design and optimization of a superconducting cable conductor is the control of the current distribution among single tapes and layers. This distribution is to a large degree determined by inductances, since the resistances are low. The self and mutual inductances...... of transport current and current distribution.This presentation is based on a number of experiments performed on prototype superconducting cable conductors. The critical current (1uV/cm) of the conductor at 77K was 1590 A (cable #1) and 3240 A (cable #2) respectively.At an rms current of 2 kA (50 Hz) the AC......-loss was measured on cable #2 to 0.6W/mxphase. This is, to our knowledge, the lowest AC-loss (at 2kA and 77K) of a high temperature superconducting cable conductor reported so far....

Frequency analysis of a tower-cable coupled system

Energy Technology Data Exchange (ETDEWEB)

Park, Moo Yeol [Young Sin Precision Engineering Ltd., Gyungju (Korea, Republic of); Kim, Seock Hyun; Park, In Su [Kangwon National University, Chuncheon (Korea, Republic of); Cui, Chengxun [Yanbian University, Yangji (China)

2013-06-15

This study considers the prediction of natural frequency to avoid resonance in a wind turbine tower- cable coupled system. An analytical model based on the Rayleigh-Ritz method is proposed to predict the resonance frequency of a wind turbine tower structure supported by four guy cables. To verify the validity of the analytical model, a small tower-cable model is manufactured and tested. The frequency and mode data of the tower model are obtained by modal testing and finite element analysis. The validity of the proposed method is verified through the comparison of the frequency analysis results. Finally, using a parametric study with the analytical model, we identified how the cable tension and cable angle affect the resonance frequency of the wind turbine tower structure. From the analysis results, the tension limit and optimal angle of the cable are identified.

Development of the qualitative techniques for monitoring of the power cables condition using infrared analysis

International Nuclear Information System (INIS)

Puiu, D.; Gyongyosi, T.; Dinu, E.; Cristi, P.

2015-01-01

The specimens analysed have been sampled from CYY 3 x 25 mm type cable sections. These sections were 3.5 mm long and have been accelerated thermal aged (by Joule Lenz effect), the thermal ageing time equivalent for NPP operation being of 10, 20, 30, 40 and 50 years. This technique is using the fact that, the polymers are degrading, the structure changes taking place leads on development of some new cross-linking having different absorption characteristics than the initial un-aged material linking. The dominant oxidation mechanisms for the aged polymers in air are producing bunch of carbonyl O=C<. In the infrared (IR) spectrum, the carbonyl bunch shows a vibration of the characteristic valence at reciprocal characteristic wave band about 1720 cm-1.The absorbance at 1720 cm-1 trends to grow related to increasing of degradation. The results are useful to identify, model and manage the power cable material ageing phenomenon in the NPP. (authors)

24 CFR 3285.704 - Telephone and cable TV.

Science.gov (United States)

2010-04-01

... 24 Housing and Urban Development 5 2010-04-01 2010-04-01 false Telephone and cable TV. 3285.704....704 Telephone and cable TV. Refer to § 3285.906 for considerations pertinent to installation of telephone and cable TV. ...

The optimum spanning catenary cable

Science.gov (United States)

Wang, C. Y.

2015-03-01

A heavy cable spans two points in space. There exists an optimum cable length such that the maximum tension is minimized. If the two end points are at the same level, the optimum length is 1.258 times the distance between the ends. The optimum lengths for end points of different heights are also found.

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

Copper Cable Recycling Technology. Innovative Technology Summary Report

International Nuclear Information System (INIS)

2001-01-01

The United States Department of Energy (DOE) continually seeks safer and more cost-effective technologies for use in deactivation and decommissioning (D and D) of nuclear facilities. The Deactivation and Decommissioning Focus Area (DDFA) of the DOE's Office of Science and Technology (OST) sponsors large-scale demonstration and deployment projects (LSDDPs). At these LSDDPs, developers and vendors of improved or innovative technologies showcase products that are potentially beneficial to the DOE's projects and to others in the D and D community. Benefits sought include decreased health and safety risks to personnel and the environment, increased productivity, and decreased costs of operation. The Idaho National Engineering and Environmental Laboratory (INEEL) generated a list of statements defining specific needs and problems where improved technology could be incorporated into ongoing D and D tasks. One such need is to reduce the volume of waste copper wire and cable generated by D and D. Deactivation and decommissioning activities of nuclear facilities generates hundreds of tons of contaminated copper cable, which are sent to radioactive waste disposal sites. The Copper Cable Recycling Technology separates the clean copper from contaminated insulation and dust materials in these cables. The recovered copper can then be reclaimed and, more importantly, landfill disposal volumes can be reduced. The existing baseline technology for disposing radioactively contaminated cables is to package the cables in wooden storage boxes and dispose of the cables in radioactive waste disposal sites. The Copper Cable Recycling Technology is applicable to facility decommissioning projects at many Department of Energy (DOE) nuclear facilities and commercial nuclear power plants undergoing decommissioning activities. The INEEL Copper Cable Recycling Technology Demonstration investigated the effectiveness and efficiency to recycle 13.5 tons of copper cable. To determine the effectiveness

Development of radiation resistant PEEK insulation cable

International Nuclear Information System (INIS)

Mio, Keigo; Ogiwara, Norio; Hikichi, Yusuke; Furukori, Hisayoshi; Arai, Hideyuki; Nishizawa, Daiji; Nishidono, Toshiro

2009-04-01

Material characterization and development has been carried out for cable insulation suitable for use in the J-PARC 3-GeV RCS radiation environment. In spite of its high cost, PEEK (polyether-ether-ketone) has emerged as the leading candidate satisfying requirements of being non-halogen based, highly incombustible and with radiation resistant at least 10 MGy, along with the usual mechanical characteristics such as good elongation at break, which are needed in a cable insulation. Gamma-ray irradiation tests have been done in order to study radiation resistance of PEEK cable. Further, mechanical, electrical and fire retardant characteristics of a complete cable such as would be used at the J-PARC RCS were investigated. As a result, PEEK cables were shown to be not degraded by radiation up to at least 10 MGy, and thus could be expected to operate stably under the 3-GeV RCS radiation environment. (author)

Development of environmental-friendly wire and cable

International Nuclear Information System (INIS)

Ueno, Keiji

1996-01-01

The electron beam technology has been used in many industrial fields as a method of conventional polymer modification or optimum processability. The main industrial fields of radiation crosslinking are wire and cable, heat shrinkable tubings, plastic foams, precuring of tires, floppy disk curing, foods packaging films, and so on. The radiation crosslinking of wire and cable was started in 1961 in Japan and 15 wire and cable companies are now using electron beam accelerators for production or R and D. The dominant characteristics of crosslinking of insulation materials are application at high temperature, good oil and chemical resistibility and high mechanical properties. These radiation crosslinking wire and cable are applied widely in electronics equipments and automobiles. Recently, electronics manufacturers have indicated deep concern over the effects on the environment. Wire and cable also are required to be applicable for environmental preservation. (J.P.N.)

Differences in Muscle Activation and Kinematics Between Cable-Based and Selectorized Weight Training.

Science.gov (United States)

Signorile, Joseph F; Rendos, Nicole K; Heredia Vargas, Hector H; Alipio, Taislaine C; Regis, Rebecca C; Eltoukhy, Moataz M; Nargund, Renu S; Romero, Matthew A

2017-02-01

Signorile, JF, Rendos, NK, Heredia Vargas, HH, Alipio, TC, Regis, RC, Eltoukhy, MM, Nargund, RS, and Romero, MA. Differences in muscle activation and kinematics between cable-based and selectorized weight training. J Strength Cond Res 31(2): 313-322, 2017-Cable resistance training machines are showing resurgent popularity and allow greater number of degrees of freedom than typical selectorized equipment. Given that specific kinetic chains are used during distinct activities of daily living (ADL), cable machines may provide more effective interventions for some ADL, whereas others may be best addressed using selectorized equipment. This study examined differences in activity levels (root mean square of the EMG [rmsEMG]) of 6 major muscles (pectoralis major, PM; anterior deltoid, AD; biceps brachii, BB; rectus abdominis, RA; external obliques, EO; and triceps brachii, TB) and kinematics of multiple joints between a cable and standard selectorized machines during the biceps curl, the chest press, and the overhead press performed at 1.5 seconds per contractile stage. Fifteen individuals (9 men, 6 women; mean age ± SD, 24.33 ± 4.88 years) participated. Machine order was randomized. Significant differences favoring cable training were seen for PM and AD during biceps curl; BB, AD, and EO for chest press; and BB and EO during overhead press (p ≤ 0.05). Greater starting and ending angles were seen for the elbow and shoulder joints during selectorized biceps curl, whereas hip and knee starting and ending angles were greater for cable machine during chest and overhead presses (p < 0.0001). Greater range of motion (ROM) favoring the cable machine was also evident (p < 0.0001). These results indicate that utilization patterns of selected muscles, joint angles, and ROMs can be varied because of machine application even when similar exercises are used, and therefore, these machines can be used selectively in training programs requiring specific motor or biomechanical

Defying c-Abl signaling circuits through small allosteric compounds

Directory of Open Access Journals (Sweden)

Stefania eGonfloni

2014-11-01

Full Text Available Many extracellular and intracellular signals promote the c-Abl tyrosine kinase activity. c-Abl in turn triggers a multitude of changes either in protein phosphorylation or in gene expression in the cell. Yet, c-Abl takes part in diverse signaling routes because of several domains linked to its catalytic core. Complex conformational changes turn on and off its kinase activity. These changes affect surface features of the c-Abl kinase and likely its capability to bind actin and/or DNA. Two specific inhibitors (ATP-competitive or allosteric compounds regulate the c-Abl kinase through different mechanisms. NMR studies show that a c-Abl fragment (SH3-SH2-linker-SH1 adopts different conformational states upon binding to each inhibitor. This supports an unconventional use for allosteric compounds to unraveling physiological c-Abl signaling circuits.

Method of exchanging cables of neutron monitoring instrumentation tube and folding device of the cable

International Nuclear Information System (INIS)

Sakamaki, Kazuo.

1990-01-01

In a BWR type reactor, a wide range monitor (WRNM) is used instead of a conventional neutron source range monitor (SRM) or an intermediate range monitor (IRM). The WRNM is always fixed to a predetermined position in a reactor core while containing a detection section in a dry tube, different from a conventional monitor. Accordingly, driving devices for the conventional detection section such as in SRM and IRM are not necessary but, when the reactor is operated for a long period of time, it is sometimes necessary to be replaced with new WRNM. According to the present invention, the cable of the detector placed in a neutron instrumentation tube is connected to a cable take-up drum in a take-up device passing through a cask. Then, the cable is taken-up by driving the take-up drum by a driving motor and the WRNM detection section attached to the top end of the cable is contained in the cask. With this constitution, replacing and processing operation for the detection section can be facilitated and operator's exposure dose can be reduced. (I.S.)

Total Magnetic Field Signatures over Submarine HVDC Power Cables

Science.gov (United States)

Johnson, R. M.; Tchernychev, M.; Johnston, J. M.; Tryggestad, J.

2013-12-01

Mikhail Tchernychev, Geometrics, Inc. Ross Johnson, Geometrics, Inc. Jeff Johnston, Geometrics, Inc. High Voltage Direct Current (HVDC) technology is widely used to transmit electrical power over considerable distances using submarine cables. The most commonly known examples are the HVDC cable between Italy and Greece (160 km), Victoria-Tasmania (300 km), New Jersey - Long Island (82 km) and the Transbay cable (Pittsburg, California - San-Francisco). These cables are inspected periodically and their location and burial depth verified. This inspection applies to live and idle cables; in particular a survey company could be required to locate pieces of a dead cable for subsequent removal from the sea floor. Most HVDC cables produce a constant magnetic field; therefore one of the possible survey tools would be Marine Total Field Magnetometer. We present mathematical expressions of the expected magnetic fields and compare them with fields observed during actual surveys. We also compare these anomalies fields with magnetic fields produced by other long objects, such as submarine pipelines The data processing techniques are discussed. There include the use of Analytic Signal and direct modeling of Total Magnetic Field. The Analytic Signal analysis can be adapted using ground truth where available, but the total field allows better discrimination of the cable parameters, in particular to distinguish between live and idle cable. Use of a Transverse Gradiometer (TVG) allows for easy discrimination between cable and pipe line objects. Considerable magnetic gradient is present in the case of a pipeline whereas there is less gradient for the DC power cable. Thus the TVG is used to validate assumptions made during the data interpretation process. Data obtained during the TVG surveys suggest that the magnetic field of a live HVDC cable is described by an expression for two infinite long wires carrying current in opposite directions.

30 CFR 75.804 - Underground high-voltage cables.

Science.gov (United States)

2010-07-01

... AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Underground High-Voltage Distribution § 75.804 Underground high-voltage cables. (a) Underground high-voltage cables used in resistance... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Underground high-voltage cables. 75.804 Section...

Rapid optimization of tension distribution for cable-driven parallel manipulators with redundant cables

Science.gov (United States)

Ouyang, Bo; Shang, Weiwei

2016-03-01

The solution of tension distributions is infinite for cable-driven parallel manipulators(CDPMs) with redundant cables. A rapid optimization method for determining the optimal tension distribution is presented. The new optimization method is primarily based on the geometry properties of a polyhedron and convex analysis. The computational efficiency of the optimization method is improved by the designed projection algorithm, and a fast algorithm is proposed to determine which two of the lines are intersected at the optimal point. Moreover, a method for avoiding the operating point on the lower tension limit is developed. Simulation experiments are implemented on a six degree-of-freedom(6-DOF) CDPM with eight cables, and the results indicate that the new method is one order of magnitude faster than the standard simplex method. The optimal distribution of tension distribution is thus rapidly established on real-time by the proposed method.

Thin film conductors for self-equalizing cables

Science.gov (United States)

Owen, G.; Trutna, W. R.; Orsley, T. J.; Lucia, F.; Daly, C. B.

2017-10-01

Self-equalizing cables using hollow conductors with wall thickness less than the skin depth were proposed in 1929. However, they do not appear ever to have been widely used, although the idea has resurfaced and been refined from time to time. In the early 2000's, self-equalizing conductors consisting of solid magnetic steel cores coated with silver were developed by W.L. Gore, and used in their 2.5 Gb/s "Eye-Opener" cables, although higher speed versions never appeared. We have revived the original 1929 idea, proposing to use glass as a solid insulating core. This technology can potentially work at frequencies of many 10's of GHz. Possible uses include short range GHz links such as USB and Thunderbolt, and intra-rack interconnections in data centers. Our feasibility experiments have validated the principle. Copper coated glass fibers can, in principle, be manufactured, but in these tests, the conductors were capillaries internally coated with silver as these are easily obtainable, relatively inexpensive and serve to test the concept. The performance of these experimental twin lead cables corresponds to calculations, confirming the general principle. By calculation, we have compared the performance of cables made from copper-on-insulator conductors to that of similar cables made with solid copper conductors, and verified that copper-on-insulator cables have significantly less frequency dependent loss. We have also made and tested cables with copper on PEEK conductors as surrogates for copper on glass fiber.

Modeling Cable and Guide Channel Interaction in a High-Strength Cable-Driven Continuum Manipulator.

Science.gov (United States)

Moses, Matthew S; Murphy, Ryan J; Kutzer, Michael D M; Armand, Mehran

2015-12-01

This paper presents several mechanical models of a high-strength cable-driven dexterous manipulator designed for surgical procedures. A stiffness model is presented that distinguishes between contributions from the cables and the backbone. A physics-based model incorporating cable friction is developed and its predictions are compared with experimental data. The data show that under high tension and high curvature, the shape of the manipulator deviates significantly from a circular arc. However, simple parametric models can fit the shape with good accuracy. The motivating application for this study is to develop a model so that shape can be predicted using easily measured quantities such as tension, so that real-time navigation may be performed, especially in minimally-invasive surgical procedures, while reducing the need for hazardous imaging methods such as fluoroscopy.

Debris from cobalt-chrome cable may cause acetabular loosening.

Science.gov (United States)

Kelley, S S; Johnston, R C

1992-12-01

To address the issue of nonunion with trochanteric osteotomy, surgeons have experimented with various modes of fixation, wire and cable being the two most popular. From a group of 643 primary cemented total hip arthroplasties performed by a single surgeon via the trans-trochanteric approach, minimum four-year roentgenographic follow-up evaluations were performed on 322 hips (50%). The method of fixation was stainless steel monofilament wire in 162 cases and Co-Cr cable in 160. Trochanteric union rates were 75% (122 patients) for the wire group and 79% (126 patients) for the cable. Breakage rates of the entire trochanteric fixation construction (all three wires or cables) were 43% (68 patients) for the wire and 12% (20 patients) for the cable. Unraveled cable was seen in 56% of the hips (90 patients), and in 47% of these hips, there were no broken cables. Blinded roentgenographic analysis of the acetabulum, preformed independently, revealed that loosening of the acetabulum in the cable group was greater than in the wire group. Cables offer no significant benefit over wires and may have potential adverse effects. Generation of significant particulate debris was noted roentgenographically, and marked reaction/destruction was found at the time of revision surgery.

Fault Management of a Cold Dielectric HTS Power Transmission Cable

International Nuclear Information System (INIS)

Maguire, J; Allais, A; Yuan, J; Schmidt, F; Hamber, F; Welsh, Tom

2006-01-01

High temperature superconductor (HTS) power transmission cables offer significant advantages in power density over conventional copper-based cables. As with conventional cables, HTS cables must be safe and reliable when abnormal conditions, such as local and through faults, occur in the power grid. Due to the unique characteristics of HTS power cables, the fault management of an HTS cable is different from that of a conventional cable. Issues, such as nitrogen bubble formation within lapped dielectric material, need to be addressed. This paper reviews the efforts that have been performed to study the fault conditions of a cold dielectric HTS power cable. As a result of the efforts, a fault management scheme has been developed, which provides both local and through faults system protection. Details of the fault management scheme with examples are presented

Improved practical formulas for estimation of cable tension by vibration method; Shindoho ni yoru cable choryoku jitsuyo santeishiki no hosei

Energy Technology Data Exchange (ETDEWEB)

Zui, H. [Setsunan University, Osaka (Japan). Faculty of Engineering; Shinke, T. [Kobe Technical College, Kobe, Kobe (Japan); Hamazaki, Y. [Kobe Steel, Ltd., Kobe (Japan)

1995-10-21

The vibration method is usually utilized on the measurement of cable tension during construction of cable bridge such as Nielsen bridges or cable stayed bridges. Practical formula for the vibration method previously proposed by authors is often used where bending rigidity is taken into account. These formula, however, have a certain limit of application and do not yield good results when the cable is not slender or not enough mentioned. The practical formula is modified to improve the accuracy and new formulas are made. The new practical formulas are applicable to any cables, regardless of its length and tension in it. The accuracy is confirmed through comparison of the value obtained by practical formulas with measured values and calculated value by F.E.M. 2 refs., 4 figs., 1 tab.

30 CFR 75.600 - Trailing cables; flame resistance.

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Trailing cables; flame resistance. 75.600 Section 75.600 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE... cables; flame resistance. [Statutory Provisions] Trailing cables used in coal mines shall meet the...

Dynamic characteristics of stay cables with inerter dampers

Science.gov (United States)

Shi, Xiang; Zhu, Songye

2018-06-01

This study systematically investigates the dynamic characteristics of a stay cable with an inerter damper installed close to one end of a cable. The interest in applying inerter dampers to stay cables is partially inspired by the superior damping performance of negative stiffness dampers in the same application. A comprehensive parametric study on two major parameters, namely, inertance and damping coefficients, are conducted using analytical and numerical approaches. An inerter damper can be optimized for one vibration mode of a stay cable by generating identical wave numbers in two adjacent modes. An optimal design approach is proposed for inerter dampers installed on stay cables. The corresponding optimal inertance and damping coefficients are summarized for different damper locations and interested modes. Inerter dampers can offer better damping performance than conventional viscous dampers for the target mode of a stay cable that requires optimization. However, additional damping ratios in other vibration modes through inerter damper are relatively limited.

Integrity assessment of grouted posttensioning cables and reinforced concrete of a nuclear containment building

Science.gov (United States)

Philipose, K.; Shenton, B.

2011-04-01

The Containment Buildings of CANDU Nuclear Generating Stations were designed to house nuclear reactors and process equipment and also to provide confinement of releases from a potential nuclear accident such as a Loss Of Coolant Accident (LOCA). To meet this design requirement, a post-tensioning system was designed to induce compressive stresses in the structure to counteract the internal design pressure. The CANDU reactor building at Gentilly-1 (G-1), Quebec, Canada (250 MWe) was built in the early 1970s and is currently in a decommissioned state. The structure at present is under surveillance and monitoring. In the year 2000, a field investigation was conducted as part of a condition assessment and corrosion was detected in some of the grouted post-tension cable strands. However, no further work was done at that time to determine the cause, nature, impact and extent of the corrosion. An investigation of the Gentilly-1 containment building is currently underway to assess the condition of grouted post-tensioning cables and reinforced concrete. At two selected locations, concrete and steel reinforcements were removed from the containment building wall to expose horizontal cables. Individual cable strands and reinforcement bars were instrumented and measurements were taken in-situ before removing them for forensic examination and destructive testing to determine the impact of ageing and corrosion. Concrete samples were also removed and tested in a laboratory. The purpose of the field investigation and laboratory testing, using this structure as a test bed, was also to collect material ageing data and to develop potential Nondestructive Examination (NDE) methods to monitor Containment Building Integrity. The paper describes the field work conducted and the test results obtained for concrete, reinforcement and post-tensioning cables.

Integrity assessment of grouted posttensioning cables and reinforced concrete of a nuclear containment building

Directory of Open Access Journals (Sweden)

Shenton B.

2011-04-01

Full Text Available The Containment Buildings of CANDU Nuclear Generating Stations were designed to house nuclear reactors and process equipment and also to provide confinement of releases from a potential nuclear accident such as a Loss Of Coolant Accident (LOCA. To meet this design requirement, a post-tensioning system was designed to induce compressive stresses in the structure to counteract the internal design pressure. The CANDU reactor building at Gentilly-1 (G-1, Quebec, Canada (250 MWe was built in the early 1970s and is currently in a decommissioned state. The structure at present is under surveillance and monitoring. In the year 2000, a field investigation was conducted as part of a condition assessment and corrosion was detected in some of the grouted post-tension cable strands. However, no further work was done at that time to determine the cause, nature, impact and extent of the corrosion. An investigation of the Gentilly-1 containment building is currently underway to assess the condition of grouted post-tensioning cables and reinforced concrete. At two selected locations, concrete and steel reinforcements were removed from the containment building wall to expose horizontal cables. Individual cable strands and reinforcement bars were instrumented and measurements were taken in-situ before removing them for forensic examination and destructive testing to determine the impact of ageing and corrosion. Concrete samples were also removed and tested in a laboratory. The purpose of the field investigation and laboratory testing, using this structure as a test bed, was also to collect material ageing data and to develop potential Nondestructive Examination (NDE methods to monitor Containment Building Integrity. The paper describes the field work conducted and the test results obtained for concrete, reinforcement and post-tensioning cables.

Development of innovative superconducting DC power cable

Energy Technology Data Exchange (ETDEWEB)

Matsushita, Teruo; Kiuchi, Masaru [Dept. of Computer Science and Electronics Kyushu Institute of Technology, Iizuka (Japan)

2017-09-15

It is required to reduce the cost of superconducting cable to realize a superconducting DC power network that covers a wide area in order to utilize renewable energy. In this paper a new concept of innovative cable is introduced that can enhance the current-carrying capacity even though the same superconducting tape is used. Such a cable can be realized by designing an optimal winding structure in such a way that the angle between the tape and magnetic field becomes small. This idea was confirmed by preliminary experiments for a single layer model cable made of Bi-2223 tapes and REBCO coated conductors. Experiments of three and four layer cables of practical sizes were also done and it was found that the current-carrying capacity increased as theoretically predicted. If the critical current properties of commercial superconducting tapes are further improved in a parallel magnetic field, the enhancement will become pronounced and this technology will surely contribute to realization of superconducting DC power network.

2nd International Conference on Cable-Driven Parallel Robots

CERN Document Server

Bruckmann, Tobias

2015-01-01

This volume presents the outcome of the second forum to cable-driven parallel robots, bringing the cable robot community together. It shows the new ideas of the active researchers developing cable-driven robots. The book presents the state of the art, including both summarizing contributions as well as latest research and future options. The book cover all topics which are essential for cable-driven robots: Classification Kinematics, Workspace and Singularity Analysis Statics and Dynamics Cable Modeling Control and Calibration Design Methodology Hardware Development Experimental Evaluation Prototypes, Application Reports and new Application concepts

Fiscal 1997 report on the results of the international standardization R and D. Development of a test method of halogen-free flame-retardant cables and a study of the cable standards; 1997 nendo seika hokokusho kokusai hyojun soseigata kenkyu kaihatsu. Non halogen nannen cable no shiken hoho kaihatsu narabini cable kikaku no kento

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-03-01

As for halogen-free flame-retardant cables with high recyclability and safety (HFFR cables), the development is being promoted in many countries as a next generation cable. The standard of HFFR cables has been set up by some countries and groups in the U.S. and Europe, but the international standard has not yet been established independently. The purpose of this R and D is the development of a test method to appropriately evaluate the performance of HFFR cables and its standardization, and the proposal of the international standardization on common items of the cable standard. A study group was sent to the U.S. and Europe to investigate the development, application status and test methods of the HFFR cable overseas. The ion chromatography and FT-IR method were studied as methods to evaluate corrosivity/toxicity of the gases emitted in combustion. The performance of HFFR cables in Japan and abroad was also evaluated mainly by IEC standards. Further, considering the results of the overseas surveys, the structure and details of the international standard plan on HFFR cables were studied, and approaches to the international standardization were studied. 32 refs., 31 figs., 54 tabs.

Stationary operational behavior unsymmetrical superconducting three-phase cable

Energy Technology Data Exchange (ETDEWEB)

Iser, R.

1974-01-01

A superconducting cable with a coaxial conductor arrangement is electrically unsymmetrical. Voltage and current relationships are analyzed for such a cable where, as a result of reactance and capacitance matrices being unsymmetric, large voltage unsymmetry appears. This limits the practical length of this type of cable. It is shown that a significant gain in symmetry is attained by the use of two cables connected in parallel. The compensating current which then occurs involves no disadvantage. The circuit described permits overloads of up to 100 percent.

Influence of Icing on Bridge Cable Aerodynamics

DEFF Research Database (Denmark)

Koss, Holger; Frej Henningsen, Jesper; Olsen, Idar

2013-01-01

In recent years the relevance of ice accretion for wind-induced vibration of structural bridge cables has been recognised and became a subject of research in bridge engineering. Full-scale monitoring and observation indicate that light precipitation at moderate low temperatures between zero and -5......°C may lead to large amplitude vibrations of bridge cables under wind action. For the prediction of aerodynamic instability quasi-steady models have been developed estimating the cable response magnitude based on structural properties and aerodynamic force coefficients for drag, lift and torsion...... forces of different bridge cables types. The experiments were conducted in a wind tunnel facility capable amongst others to simulate incloud icing conditions....

Automated wireless monitoring system for cable tension using smart sensors

Science.gov (United States)

Sim, Sung-Han; Li, Jian; Jo, Hongki; Park, Jongwoong; Cho, Soojin; Spencer, Billie F.; Yun, Chung-Bang

2013-04-01

Cables are critical load carrying members of cable-stayed bridges; monitoring tension forces of the cables provides valuable information for SHM of the cable-stayed bridges. Monitoring systems for the cable tension can be efficiently realized using wireless smart sensors in conjunction with vibration-based cable tension estimation approaches. This study develops an automated cable tension monitoring system using MEMSIC's Imote2 smart sensors. An embedded data processing strategy is implemented on the Imote2-based wireless sensor network to calculate cable tensions using a vibration-based method, significantly reducing the wireless data transmission and associated power consumption. The autonomous operation of the monitoring system is achieved by AutoMonitor, a high-level coordinator application provided by the Illinois SHM Project Services Toolsuite. The monitoring system also features power harvesting enabled by solar panels attached to each sensor node and AutoMonitor for charging control. The proposed wireless system has been deployed on the Jindo Bridge, a cable-stayed bridge located in South Korea. Tension forces are autonomously monitored for 12 cables in the east, land side of the bridge, proving the validity and potential of the presented tension monitoring system for real-world applications.

Solid-cryogen-stabilized, cable-in-conduit (CIC) superconducting cables

Science.gov (United States)

Voccio, J. P.; Michael, P. C.; Bromberg, L.; Hahn, S.

2015-12-01

This paper considers the use of a solid cryogen as a means to stabilize, both mechanically and thermally, magnesium diboride (MgB2) superconducting strands within a dual-channel cable-in-conduit (CIC) cable for use in AC applications, such as a generator stator winding. The cable consists of two separate channels; the outer channel contains the superconducting strands and is filled with a fluid (liquid or gas) that becomes solid at the device operating temperature. Several options for fluid will be presented, such as liquid nitrogen, hydrocarbons and other chlorofluorocarbons (CFCs) that have a range of melting temperatures and volumetric expansions (from solid at operating temperature to fixed volume at room temperature). Implications for quench protection and conductor stability, enhanced through direct contact with the solid cryogen, which has high heat capacity and thermal conductivity (compared with helium gas), will be presented. Depending on the cryogen, the conductor will be filled initially either with liquid at atmospheric conditions or a gas at high pressure (∼100 atm). After cooldown, the cryogen in the stranded-channel will be solid, essentially locking the strands in place, preventing strand motion and degradation due to mechanical deformation while providing enhanced thermal capacity for stability and protection. The effect of cryogen porosity is also considered. The relatively high heat capacity of solid cryogens at these lower temperatures (compared to gaseous helium) enhances the thermal stability of the winding. During operation, coolant flow through the open inner channel will minimize pressure drop.

Analysis of the Working Cable System of Single-span Circulating Ropeway

Directory of Open Access Journals (Sweden)

Qin Jian

2017-01-01

Full Text Available Based on the analysis of the mutual interaction between bearing cable and traction cable of single-span circulating ropeway, the calculation method is proposed for working cables of ropeway with arbitrary loads. The 5 sets nonlinear equations are set up for the working cables according to the equal spans and altitude differences of the bearing cable and the traction cable, the constant of the load running space and the bearing cable length, and the tension balance of bearing cable and traction cable beside load. The resolving method is proposed based on the Newton iterative method. The correctness and feasibility of the method are proved by the results of engineering test. From the solution, the tension and coordinate of working cables can be obtained accurately, which is meaningful for the design and analysis of the freight ropeway.

Long-term monitoring FBG-based cable load sensor

Science.gov (United States)

Zhang, Zhichun; Zhou, Zhi; Wang, Chuan; Ou, Jinping

2006-03-01

Stay cables are the main load-bearing components of stayed-cable bridges. The cables stress status is an important factor to the stayed-cable bridge structure safety evaluation. So it's very important not only to the bridge construction, but also to the long-term safety evaluation for the bridge structure in-service. The accurate measurement for cable load depends on an effective sensor, especially to meet the long time durability and measurement demand. FBG, for its great advantage of corrosion resistance, absolute measurement, high accuracy, electro-magnetic resistance, quasi-distribution sensing, absolute measurement and so on, is the most promising sensor, which can cater for the cable force monitoring. In this paper, a load sensor has been developed, which is made up of a bushing elastic supporting body, 4 FBGs uniformly-spaced attached outside of the bushing supporting body, and a temperature compensation FBG for other four FBGs, moreover a cover for protection of FBGs. Firstly, the sensor measuring principle is analyzed, and relationship equation of FBG wavelength shifts and extrinsic load has also been gotten. And then the sensor calibration experiments of a steel cable stretching test with the FBG load sensor and a reference electric pressure sensor is finished, and the results shows excellent linearity of extrinsic load and FBG wavelength shifts, and good repeatability, which indicates that such kind of FBG-based load sensor is suitable for load measurement, especially for long-term, real time monitoring of stay-cables.

Heat resistant wire and cable and heat shrinkable tubes

Energy Technology Data Exchange (ETDEWEB)

Ueno, Keiji [Sumitomo Electric Industries Ltd. (Japan)

1994-12-31

Radiation processes have been used in industrial fields (e.g. wire and cable, heat shrinkable tubes) for about 30 years. In Japan, 60 electron beam accelerators were used in R and D, 54 in wire and cable, 24 in tire rubber, 16 in paint curing, 14 in PE foam and 9 accelerators were used in heat shrinkable tubes in 1993. Many properties (e.g. solder resistance, thermal deformation, and solven resistance) of wire and cable are improved by using radiation processes, and many kinds of radiation crosslinked wire and cable are used in the consumer market (TV sets, VTR`s, audio disc players, etc.), automobiles (automobile wire harnesses, fusible link wires, sensor cables etc.), and the industrial market (computer cables, cables for keyboards, coaxial cables, etc.). Another important industrial application of E{beta} radiation process is heat shrinkable tubes. Heat shinkable tubes, heated by a hot gun, shrink 1/2 {approx} 1/3 of their inner diameters. Heat shrinkable tubes are used for covers of distributing line terminals, joint covers of telecommunication lines, protection of fuel pipe lines and so on. In this seminar, actual applications and characteristic properties of radiation crosslinked materials are presented.

Heat resistant wire and cable and heat shrinkable tubes

International Nuclear Information System (INIS)

Keiji Ueno

1994-01-01

Radiation processes have been used in industrial fields (e.g. wire and cable, heat shrinkable tubes) for about 30 years. In Japan, 60 electron beam accelerators were used in R and D, 54 in wire and cable, 24 in tire rubber, 16 in paint curing, 14 in PE foam and 9 accelerators were used in heat shrinkable tubes in 1993. Many properties (e.g. solder resistance, thermal deformation, and solven resistance) of wire and cable are improved by using radiation processes, and many kinds of radiation crosslinked wire and cable are used in the consumer market (TV sets, VTR's, audio disc players, etc.), automobiles (automobile wire harnesses, fusible link wires, sensor cables etc.), and the industrial market (computer cables, cables for keyboards, coaxial cables, etc.). Another important industrial application of Eβ radiation process is heat shrinkable tubes. Heat shinkable tubes, heated by a hot gun, shrink 1/2 ∼ 1/3 of their inner diameters. Heat shrinkable tubes are used for covers of distributing line terminals, joint covers of telecommunication lines, protection of fuel pipe lines and so on. In this seminar, actual applications and characteristic properties of radiation crosslinked materials are presented

Analysis of Harmonic Vibration of Cable-Stayed Footbridge under the Influence of Changes of the Cables Tension

Directory of Open Access Journals (Sweden)

Pakos Wojciech

2015-09-01

Full Text Available The paper presents numerical analysis of harmonically excited vibration of a cable-stayed footbridge caused by a load function simulating crouching (squats while changing the static tension in chosen cables. The intentional synchronized motion (e.g., squats of a single person or group of persons on the footbridge with a frequency close to the natural frequency of the structure may lead to the resonant vibrations with large amplitudes. The appropriate tension changes in some cables cause detuning of resonance on account of stiffness changes of structures and hence detuning in the natural frequency that is close to the excitation frequency. The research was carried out on a 3D computer model of a real structure - a cable-stayed steel footbridge in Leśnica, a quarter of Wrocław, Poland, with the help of standard computer software based on FEM COSMOS/M System.

Analysis of Harmonic Vibration of Cable-Stayed Footbridge under the Influence of Changes of the Cables Tension

Science.gov (United States)

Pakos, Wojciech

2015-09-01

The paper presents numerical analysis of harmonically excited vibration of a cable-stayed footbridge caused by a load function simulating crouching (squats) while changing the static tension in chosen cables. The intentional synchronized motion (e.g., squats) of a single person or group of persons on the footbridge with a frequency close to the natural frequency of the structure may lead to the resonant vibrations with large amplitudes. The appropriate tension changes in some cables cause detuning of resonance on account of stiffness changes of structures and hence detuning in the natural frequency that is close to the excitation frequency. The research was carried out on a 3D computer model of a real structure - a cable-stayed steel footbridge in Leśnica, a quarter of Wrocław, Poland, with the help of standard computer software based on FEM COSMOS/M System.

Thin film conductors for self-equalizing cables

Directory of Open Access Journals (Sweden)

G. Owen

2017-10-01

Full Text Available Self-equalizing cables using hollow conductors with wall thickness less than the skin depth were proposed in 1929. However, they do not appear ever to have been widely used, although the idea has resurfaced and been refined from time to time. In the early 2000’s, self-equalizing conductors consisting of solid magnetic steel cores coated with silver were developed by W.L. Gore, and used in their 2.5 Gb/s “Eye-Opener” cables, although higher speed versions never appeared. We have revived the original 1929 idea, proposing to use glass as a solid insulating core. This technology can potentially work at frequencies of many 10’s of GHz. Possible uses include short range GHz links such as USB and Thunderbolt, and intra-rack interconnections in data centers. Our feasibility experiments have validated the principle. Copper coated glass fibers can, in principle, be manufactured, but in these tests, the conductors were capillaries internally coated with silver as these are easily obtainable, relatively inexpensive and serve to test the concept. The performance of these experimental twin lead cables corresponds to calculations, confirming the general principle. By calculation, we have compared the performance of cables made from copper-on-insulator conductors to that of similar cables made with solid copper conductors, and verified that copper-on-insulator cables have significantly less frequency dependent loss. We have also made and tested cables with copper on PEEK conductors as surrogates for copper on glass fiber.

Fabrication of Nb3Sn cables for ITER toroidal field coils

International Nuclear Information System (INIS)

Isono, Takaaki; Tsutsumi, Fumiaki; Nunoya, Yoshihiko; Matsui, Kunihiro; Takahashi, Yoshikazu; Nakajima, Hideo; Ishibashi, Tatsuji; Sato, Go; Chida, Kenji; Suzuki, Rikio; Tanji, Tsutomu

2012-01-01

Cable-in-conduit conductors for ITER toroidal field (TF) coils will be operated at 68 kA and 11.8 T. The cable is composed of 1,422 strands with a diameter of 0.82 mm. There were two options for initial procurement. For option 2, the twist pitches at lower stages are longer than in option 1. Trials were performed to assess the feasibility of these options. In the trials for option 1, the nominal outer diameter of sub-cables and reduction schedule of final cables were evaluated and finalized. In the trials for option 2, problems were encountered at the third stage cabling. These problems were resolved through increasing the die size in that stage and improving the tension balance of the second-stage cables to reduce friction between the die and the cable, and also through avoiding loose twisting at both edges of the third cables. Option 2 was finally selected in 2009 based on superconducting performance enhancement of the cable. After the qualification of the fabrication procedure using fabrication of a 760-m dummy cable and a 415-m superconducting cable, mass production of the cables started in March 2010. (author)

46 CFR 111.60-6 - Fiber optic cable.

Science.gov (United States)

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Fiber optic cable. 111.60-6 Section 111.60-6 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Wiring Materials and Methods § 111.60-6 Fiber optic cable. Each fiber optic cable must— (a) Be...

Comparison of programmed and cabled re-entrance systems. Elaboration of cabled re-entrance system for a CII 90.40

International Nuclear Information System (INIS)

Perraudeau, Jean

1976-01-01

The objective of this research thesis is to study problems related to re-entrance, and, more particularly, to study a re-entrance system for a CII 90.40 computer. Such a system can be realised under a programmed or cabled form, and both approaches are described and compared. A generalisation of this comparison is briefly proposed. As the computer already possesses a programmed re-entrance system, the author focuses on the study of the cabled re-entrance system which results in an improvement of performance and possibilities provided by this computer, particularly for its use in real time. The design, realisation and development of such a cabled system are reported. A first part reports a theoretical study on re-entrance (definition, problems, applications), a presentation of the computer, a description of the programmed re-entrance system, a presentation of the principle of the chosen cabled re-entrance system, a definition of the structure and operating mode of the cabled pile and a description of its various components, and a flowchart analysis of function execution. The second part reports the practical realisation: definition, technological overview, technology used in the cabled pile, sequencing and multiplexing principle, impulse transmission, logical layouts, and circuit adjustments. The third part presents practical example. An assessment and perspectives are finally discussed

Intermodal resonance of vibrating suspended cables

NARCIS (Netherlands)

Rienstra, S.W.

2010-01-01

The weakly nonlinear free vibrations of a single suspended cable, or a coupled system of suspended cables, may be classified as gravity modes (no tension variations to leading order) and elasto-gravity modes (tension and vertical displacement equally important). It was found earlier [12] that the

Behaviour of French electrical cables under fire conditions

Energy Technology Data Exchange (ETDEWEB)

Bertrand, R.; Chaussard, M.; Gonzalez, R.; Lacoue, J.; Mattei, J.M.; Such, J.M

2001-12-01

A fire Probabilistic Safety Assessment - called fire PSA - is being carried out by the French Institute of Nuclear Safety and Protection (IPSN) to be used in the framework of the safety assessment of operating 900 MWe PWRs. The aim of this study is to evaluate the core damage conditional probability which could result from a fire. A fire can induce unavailability of safety equipment notably damaging electrical cables that are a significant risk contributor. The purpose of this communication is to present the electrical cable fire tests carried out by IPSN to identify the failure modes and to determine the cable damage criteria. Moreover, are indicated the impact of each kind of cable failure mode and the methodology used to estimate the conditional probability of a failure mode when cable damage occurred. (authors)

Young's moduli of cables for high field superconductive dipole magnet

International Nuclear Information System (INIS)

Yamada, Shunji; Shintomi, Takakazu.

1983-01-01

Superconductive dipole magnets for big accelerators are subjected to enormous electro-magnetic force, when they are operated with high field such as 10 Tesla. They should be constructed by means of superconductive cables, which have high Young's modulus, to obtain good performance. To develop such cables we measured the Young's moduli of cables for practical use of accelerator magnets. They are monolithic and compacted strand cables. We measured also Young's moduli of monolithic copper and brass cables for comparison. The obtained data showed the Young's moduli of 35 and 15 GPa for the monolithic and compacted strand cables, respectively. (author)

Leaky coaxial cable signal transmission for remote facilities

Science.gov (United States)

Smith, S. F.; Crutcher, R. I.

To develop reliable communications methods to meet the rigorous requirements for nuclear hot cells and similar environments, including control of cranes, transporters, and advanced servomanipulators, the Consolidated Fuel Reprocessing Program (CFRP) at Oak Ridge National Laboratory (ORNL) has conducted extensive tests of numerous technologies to determine their applicability to remote operations. To alleviate the need for large bundles of cables that must accommodate crane/transporter motion relative to the boundaries of the cell, several transmission techniques are available, including slotted-line radio-frequency couplers, infrared beams, fiber-optic cables, free-space microwave, and inductively coupled leaky coaxial cable. This paper discusses the general characteristics, mode of operation, and proposed implementation of leaky coaxial cable technology in a waste-handling facility scheduled to be built in the near future at ORNL. In addition, specific system hardware based around the use of leaky coaxial cable is described in detail. Finally, data from a series of radiation exposure tests conducted by the CFRP on several samples of the basic leaky coaxial cable and associated connectors are presented.

Device for guiding various diameter size cable

Energy Technology Data Exchange (ETDEWEB)

Litvinov, I.M.; Klauzer, L.P.; Yeganov, L.I.; Zaripov, A.M.

1982-01-30

A design is submitted for a device to guide cable of various diameters. This device consists of a profiled multiple-pass roller, and clamps for uniting cut cable. This design is simplified by allowing both the rollers and their supports to rotate on the roller axis thus facilitating interaction with the clamps. The working surface of the supports is evolute while the outside surfaces have screw-channels for transfering the cable from one roller pass to the other.

Wear resistant performance of highly cross-linked and annealed ultra-high molecular weight polyethylene against ceramic heads in total hip arthroplasty.

Science.gov (United States)

Sato, Taishi; Nakashima, Yasuharu; Akiyama, Mio; Yamamoto, Takuaki; Mawatari, Taro; Itokawa, Takashi; Ohishi, Masanobu; Motomura, Goro; Hirata, Masanobu; Iwamoto, Yukihide

2012-12-01

The purpose of this study was to examine the effects of ceramic femoral head material, size, and implantation periods on the wear of annealed, cross-linked ultra-high molecular weight polyethylene (UHMWPE) (XLPE) in total hip arthroplasty compared to non-cross-linked conventional UHMWPE (CPE). XLPE was fabricated by cross-linking with 60 kGy irradiation and annealing. Femoral heads made from zirconia and alumina ceramics and cobalt-chrome (CoCr) of 22 or 26 mm diameter were used. In this retrospective cohort study, the femoral head penetration into the cup was measured digitally on radiographs of 367 hips with XLPE and 64 hips with CPE. The average follow-up periods were 6.3 and 11.9 years, respectively. Both XLPE creep and wear rates were significantly lower than those of CPE (0.19 mm vs. 0.44 mm, 0.0001 mm/year vs. 0.09 mm/year, respectively). Zirconia displayed increased wear rates compared to alumina in CPE; however, there was no difference among head materials in XLPE (0.0008, 0.00007, and -0.009 mm/year for zirconia, alumina, and CoCr, respectively). Neither head size or implantation period impacted XLPE wear. In contrast to CPE, XLPE displayed low wear rates surpassing the effects of varying femoral head material, size, implantation period, and patient demographics. Further follow-up is required to determine the long-term clinical performance of the annealed XLPE. Copyright © 2012 Orthopaedic Research Society.

30 CFR 75.601 - Short circuit protection of trailing cables.

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Short circuit protection of trailing cables. 75... MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Trailing Cables § 75.601 Short circuit protection of trailing cables. [Statutory Provisions] Short circuit protection for trailing cables...

Power plant cable condition monitoring and testing at Georgia Power

International Nuclear Information System (INIS)

Champion, T.C.

1988-01-01

Georgia Power's Research Center has been heavily involved in the evaluation of electrical insulating materials and cables since its inception more than 17 years ago. For the past ten years that expertise has been applied to cables used in generation plants. This paper discusses the results of two test programs. The first is a quality control inspection on 169 samples of new power generation cables. The second is a material degradation evaluation on four short cable samples removed from a coal fired plant during an equipment upgrade. The new material evaluation was performed to identify the cause of a high failure rate upon initial hi-pot testing of newly installed cables. The material degradation evaluation was performed to evaluate the need for replacement of existing cables during an equipment upgrade. Results of the evaluations have led to development of a detailed proposal for a program to evaluate cable degradation and remaining life for cables used in power generation facilities

Configuration of an inelastic flexible anchored cable

Directory of Open Access Journals (Sweden)

T. P. Dreyer

1992-07-01

Full Text Available Consider an inelastic, perfectly flexible cable with given external forces acting on the total length of the cable. The one end-point is fixed in the origin and the other end-point is anchored at a given point (a;b;c in space. The resulting configuration of the cable in space can be modelled by a system of non-linear differential equations. In this article it is shown that this continuous model of the cable can always be solved in terms of an integral. In the special case of a constant (i.e. independent of the position on the cable external force per unit length the solution is given explicitly in terms of three constants that describe the tension at the origin. These three constants are determined by the boundary values a, b and c at the other end-point, and must be calculated in general by a numerical procedure from the three resulting simultaneous non-linear equations. A few applications of this method are shown.

Development of halogen-free cables for nuclear power plants

International Nuclear Information System (INIS)

Yamamoto, Mitsuo; Ito, Kazumi; Yaji, Takeo; Yoshida, Shin; Sakurai, Takako; Matsushita, Shigetoshi.

1990-01-01

On the occasion where serious fire accidents were experienced in the past, the need for making flame-retardant wire and cable incombustible took place and has since been generalizing. Various sorts of flame-retardant cables have already been developed and been actually used. From the viewpoint of avoiding the interference with the evacuation and fire-fighting activity in case of fire or the secondary accidents such as corrosion of the distributing panel, etc., the demand for non-halogen flame-retardant cable has rapidly been increasing in recent years in some fields of general industries, because this specific cable would generate the least amount of toxic smoke or corrosive gas even when it should burn. Similar demand has been increasing also for the cable used for nuclear power plants. In this field, earnest desire has been made for the development of non-halogen flame-retardant cable having specific environmental resistance specially required at nuclear power plants in addition to the properties and capacities required in general industries. The authors have continued examinations on the anti-environmental properties of the materials for cable such as long heat resistance, radiation resistance, steam resistance and succeeded in completing various sorts of non-halogen flame-retardant cable for nuclear power plants. In this report, we will introduce various features of the cable we have developed this time as well as the long-term reliability of non-halogen flame-retardant materials. (author)

Cable Damage Detection System and Algorithms Using Time Domain Reflectometry

Energy Technology Data Exchange (ETDEWEB)

Clark, G A; Robbins, C L; Wade, K A; Souza, P R

2009-03-24

This report describes the hardware system and the set of algorithms we have developed for detecting damage in cables for the Advanced Development and Process Technologies (ADAPT) Program. This program is part of the W80 Life Extension Program (LEP). The system could be generalized for application to other systems in the future. Critical cables can undergo various types of damage (e.g. short circuits, open circuits, punctures, compression) that manifest as changes in the dielectric/impedance properties of the cables. For our specific problem, only one end of the cable is accessible, and no exemplars of actual damage are available. This work addresses the detection of dielectric/impedance anomalies in transient time domain reflectometry (TDR) measurements on the cables. The approach is to interrogate the cable using time domain reflectometry (TDR) techniques, in which a known pulse is inserted into the cable, and reflections from the cable are measured. The key operating principle is that any important cable damage will manifest itself as an electrical impedance discontinuity that can be measured in the TDR response signal. Machine learning classification algorithms are effectively eliminated from consideration, because only a small number of cables is available for testing; so a sufficient sample size is not attainable. Nonetheless, a key requirement is to achieve very high probability of detection and very low probability of false alarm. The approach is to compare TDR signals from possibly damaged cables to signals or an empirical model derived from reference cables that are known to be undamaged. This requires that the TDR signals are reasonably repeatable from test to test on the same cable, and from cable to cable. Empirical studies show that the repeatability issue is the 'long pole in the tent' for damage detection, because it is has been difficult to achieve reasonable repeatability. This one factor dominated the project. The two-step model

New, clean handling process introduced to improve cable quality

Energy Technology Data Exchange (ETDEWEB)

Hunt, C G

1990-05-01

The clean room system introduced by Canada Wire and Cable Limited in its Toronto plant for its cable manufacturing operation is described. While clean room technology is common in the food processing industry, optical and aerospace manufacturing processes, this is the first time it has been applied to wire and cable extrusion in North America. The purpose of the clean compound handling system is to prevent particle contamination in the shielding and cable insulation materials, as part of an effort to prevent premature underground electric cable failures. Two rooms are dedicated to handling different types of insulation compound, two are dedicated to receiving semi-conducting shielding material, and the fifth room functions as an air lock for the two insulation rooms. The atmosphere is highly regulated with programmable logic control. The air supply filters capture 99.97% of all particles 0.3 microns or larger. The system also maintains air temperature, relative humidity and static pressure. The life variability of cross-linked polyethylene primary distribution cable is dependant on five factors: material purity, extra clean compound handling, cable design, manufacturing process, and installation and operation practices. The clean room system is expected to result in cable that is more resistant to water treeing failures. 2 figs.

A preliminary bending fatigue spectrum for steel monostrand cables

DEFF Research Database (Denmark)

Winkler, Jan; Fischer, Gregor; Georgakis, Christos T.

2011-01-01

This paper presents the results of the experimental study on the bending fatigue resistance of high-strength steel monostrand cables. From the conducted fatigue tests in the high-stress, low-cycle region, a preliminary bending fatigue spectrum is derived for the estimation of monostrand cable...... service life expectancy. The presented preliminary bending fatigue spectrum of high-strength monostrands is currently unavailable in the published literature. The presented results provide relevant information on the bending mechanism and fatigue characteristics of monostrand steel cables in tension...... and flexure and show that localized cable bending has a pronounced influence on the fatigue resistance of cables under dynamic excitations....

Radiation techology in cable making industry

International Nuclear Information System (INIS)

Kourim, P.; Vokal, A.

1985-01-01

Electron accelerators are used in radiation cross-linking of elastomer and thermoplastic layers of cable insulation and sheathing. Another application is cross-linking of insulation bands and moulded products to achieve thermal contractibility. Ionizing radiation is used for curing insulation lacquers on winding leads. In Czechoslovakia, problems of radiation curing of silicone rubber have been studied since 1973. Instrumentation has been installed including accelerators. The feasibility has also been studied of radiation cross-linking of insulation and semiconductor cable cores of hose-type trailing cables. Polyethylene mixes have been designed and prepared which are suitable for radiation cross-linking aimed at increasing thermal resistance above 100 degC. (M.D.)

Overcurrent experiments on HTS tape and cable conductor

DEFF Research Database (Denmark)

Tønnesen, Ole; Jensen, Kim Høj; Træholt, Chresten

2001-01-01

their critical current. In this light, it is important to investigate the response of HTS tapes and cable conductors to overcurrents several times the critical current. A number of experiments have been performed on HTS tapes and cable conductors, with currents up to 20 times the critical current. During...... overcurrent experiments, the voltage, and the temperature were measured as functions of time in order to investigate the dynamic behavior of the HTS tape and cable conductor. After each experiment, damage to the superconductors was assessed by measuring the critical current. Preliminary results show...... that within seconds an HTS tape (critical current=17 A) heats above room temperature with an overcurrent larger than 140 A. Similar overcurrent experiments showed that a HTS cable conductor could sustain damage with overcurrents exceeding 10 times the critical current of the cable conductor....

The Selling of Cable Television 1972.

Science.gov (United States)

National Cable Television Association, Inc., Washington, DC.

The 1972 Cable Television Marketing Workshop reviewed in depth a wide variety of marketing and public relations techniques as they pertain to cable television. The workshop was attended by representatives of commercial television systems throughout the United States; it was intended to disseminate the sales and marketing experience of those…

TMI cable tracer operation and maintenance manual for assembly 417910

International Nuclear Information System (INIS)

Sumstine, R.L.

1983-11-01

This manual provides technical information and instructions to operate and maintain the cable tracer designed for the Three Mile Island (TMI) Unit 2 Reactor Building. The TMI cable tracer was developed to allow TMI personnel to trace cables in cable trays that may be tested or sectioned for destructive examination

Subsea Cable Tracking by Autonomous Underwater Vehicle with Magnetic Sensing Guidance.

Science.gov (United States)

Xiang, Xianbo; Yu, Caoyang; Niu, Zemin; Zhang, Qin

2016-08-20

The changes of the seabed environment caused by a natural disaster or human activities dramatically affect the life span of the subsea buried cable. It is essential to track the cable route in order to inspect the condition of the buried cable and protect its surviving seabed environment. The magnetic sensor is instrumental in guiding the remotely-operated vehicle (ROV) to track and inspect the buried cable underseas. In this paper, a novel framework integrating the underwater cable localization method with the magnetic guidance and control algorithm is proposed, in order to enable the automatic cable tracking by a three-degrees-of-freedom (3-DOF) under-actuated autonomous underwater vehicle (AUV) without human beings in the loop. The work relies on the passive magnetic sensing method to localize the subsea cable by using two tri-axial magnetometers, and a new analytic formulation is presented to compute the heading deviation, horizontal offset and buried depth of the cable. With the magnetic localization, the cable tracking and inspection mission is elaborately constructed as a straight-line path following control problem in the horizontal plane. A dedicated magnetic line-of-sight (LOS) guidance is built based on the relative geometric relationship between the vehicle and the cable, and the feedback linearizing technique is adopted to design a simplified cable tracking controller considering the side-slip effects, such that the under-actuated vehicle is able to move towards the subsea cable and then inspect its buried environment, which further guides the environmental protection of the cable by setting prohibited fishing/anchoring zones and increasing the buried depth. Finally, numerical simulation results show the effectiveness of the proposed magnetic guidance and control algorithm on the envisioned subsea cable tracking and the potential protection of the seabed environment along the cable route.

Wind-Tunnel Investigation of the Aerodynamic Performance of Surface-Modification Cables

Directory of Open Access Journals (Sweden)

Hiroshi Katsuchi

2017-12-01

Full Text Available The wind-induced vibration of stay cables of cable-stayed bridges, which includes rain-wind-induced vibration (RWIV and dry galloping (DG, has been studied for a considerable amount of time. In general, mechanical dampers or surface modification are applied to suppress the vibration. In particular, several types of surface-modification cable, including indentation, longitudinally parallel protuberance, helical fillet, and U-shaped grooving, have been developed. Recently, a new type of aerodynamically stable cable with spiral protuberances was developed. It was confirmed that the cable has a low drag force coefficient, like an indented cable, and that it prevented the formation of water rivulets on the cable surface. In this study, the stability for RWIV of this cable was investigated with various flow angles and protuberance dimensions in a wind-tunnel test. It was found that the spiral protuberance cable is aerodynamically stable against both RWIV and DG for all test wind angles. The effects of the protuberance dimensions were also clarified. Keywords: Rain-wind-induced vibration, Dry galloping, Stay cable, Wind-tunnel test

Properties of Polymer Composites Used in High-Voltage Applications

Directory of Open Access Journals (Sweden)

Ilona Pleşa

2016-04-01

Full Text Available The present review article represents a comprehensive study on polymer micro/nanocomposites that are used in high-voltage applications. Particular focus is on the structure-property relationship of composite materials used in power engineering, by exploiting fundamental theory as well as numerical/analytical models and the influence of material design on electrical, mechanical and thermal properties. In addition to describing the scientific development of micro/nanocomposites electrical features desired in power engineering, the study is mainly focused on the electrical properties of insulating materials, particularly cross-linked polyethylene (XLPE and epoxy resins, unfilled and filled with different types of filler. Polymer micro/nanocomposites based on XLPE and epoxy resins are usually used as insulating systems for high-voltage applications, such as: cables, generators, motors, cast resin dry-type transformers, etc. Furthermore, this paper includes ample discussions regarding the advantages and disadvantages resulting in the electrical, mechanical and thermal properties by the addition of micro- and nanofillers into the base polymer. The study goals are to determine the impact of filler size, type and distribution of the particles into the polymer matrix on the electrical, mechanical and thermal properties of the polymer micro/nanocomposites compared to the neat polymer and traditionally materials used as insulation systems in high-voltage engineering. Properties such as electrical conductivity, relative permittivity, dielectric losses, partial discharges, erosion resistance, space charge behavior, electric breakdown, tracking and electrical tree resistance, thermal conductivity, tensile strength and modulus, elongation at break of micro- and nanocomposites based on epoxy resin and XLPE are analyzed. Finally, it was concluded that the use of polymer micro/nanocomposites in electrical engineering is very promising and further research work

Computer-Aided Engineering Of Cabling

Science.gov (United States)

Billitti, Joseph W.

1989-01-01

Program generates data sheets, drawings, and other information on electrical connections. DFACS program, centered around single data base, has built-in menus providing easy input of, and access to, data for all personnel involved in system, subsystem, and cabling. Enables parallel design of circuit-data sheets and drawings of harnesses. Also recombines raw information to generate automatically various project documents and drawings, including index of circuit-data sheets, list of electrical-interface circuits, lists of assemblies and equipment, cabling trees, and drawings of cabling electrical interfaces and harnesses. Purpose of program to provide engineering community with centralized data base for putting in, and gaining access to, functional definition of system as specified in terms of details of pin connections of end circuits of subsystems and instruments and data on harnessing. Primary objective to provide instantaneous single point of interchange of information, thus avoiding

Water-Tree Modelling and Detection for Underground Cables

Science.gov (United States)

Chen, Qi

In recent years, aging infrastructure has become a major concern for the power industry. Since its inception in early 20th century, the electrical system has been the cornerstone of an industrial society. Stable and uninterrupted delivery of electrical power is now a base necessity for the modern world. As the times march-on, however, the electrical infrastructure ages and there is the inevitable need to renew and replace the existing system. Unfortunately, due to time and financial constraints, many electrical systems today are forced to operate beyond their original design and power utilities must find ways to prolong the lifespan of older equipment. Thus, the concept of preventative maintenance arises. Preventative maintenance allows old equipment to operate longer and at better efficiency, but in order to implement preventative maintenance, the operators must know minute details of the electrical system, especially some of the harder to assess issues such water-tree. Water-tree induced insulation degradation is a problem typically associated with older cable systems. It is a very high impedance phenomenon and it is difficult to detect using traditional methods such as Tan-Delta or Partial Discharge. The proposed dissertation studies water-tree development in underground cables, potential methods to detect water-tree location and water-tree severity estimation. The dissertation begins by developing mathematical models of water-tree using finite element analysis. The method focuses on surface-originated vented tree, the most prominent type of water-tree fault in the field. Using the standard operation parameters of North American electrical systems, the water-tree boundary conditions are defined. By applying finite element analysis technique, the complex water-tree structure is broken down to homogeneous components. The result is a generalized representation of water-tree capacitance at different stages of development. The result from the finite element analysis

Assessment of sodium conductor distribution cable

Energy Technology Data Exchange (ETDEWEB)

None

1979-06-01

The study assesses the barriers and incentives for using sodium conductor distribution cable. The assessment considers environmental, safety, energy conservation, electrical performance and economic factors. Along with all of these factors considered in the assessment, the sodium distribution cable system is compared to the present day alternative - an aluminum conductor system. (TFD)

On Dynamic Analysis, Optimal Distribution of Cable Tention and Experiment of Cable NET Structures in Large Radio Telescope

International Nuclear Information System (INIS)

Duan, Baoyan

2002-01-01

This paper presents the researching activities, in which the nonlinear dynamic analysis, optimization of the cables' tension distribution, real 50 meters model experiment are discussed. The long cable structure has been utilized in new generation large radio telescope with the diameter of 500 meters. In design, there are six high concrete towers form which are six computer controlled long cables about 250 meters long met at a cabin, which is a hemisphere with 6 meters diameter. The cabin can be moved three dimensional to track the target. Within the cabin, there is a stable platform. The positioning precision for the platform and cabin are 4mm and 50cm respectively. By which means, the poisoning accuracy can be received becomes a sensible and important problem. For the sake of this, study on vibration of cable with respect to random wind, such as nonlinear response, vortex and galloping, is investigated in this paper. Desirable design is that the tension forces among the six long cables are the same, at least as even as possible. This will be benefit to the control of the system, so that the higher dynamic positioning precision is easy to be obtained. To meet this kind of requirement, the optimal distribution of the cable tensions among cables is discussed and pretty good result is received. Before the real 500 meters diameters antenna is built, an experiment model with 50 meters diameter was built in Xidian University of China, shown in figure 2. The dynamic analysis on vibration (random wind response, vortex and galloping), optimization of the cable tensions' distribution is made with good result. Lots of 50-meter-model site experiments are carried out with useful and valuable results, form which the theory and simulation model has been improved repeatedly until both the model simulation and experiment results are very closed so that the difference can be accepted from the viewpoint of thoroughly, systematically and deeply in the paper. The conclusion

Broadband Wireline Provider Service: Cable Modem - Other; BBRI_cableOther12

Data.gov (United States)

University of Rhode Island Geospatial Extension Program — This dataset represents the availability of wireline broadband Internet access in Rhode Island via "Cable Modem - Other" technology. Broadband availability is...

Potential Impact of Submarine Power Cables on Crab Harvest

Science.gov (United States)

Bull, A. S.; Nishimoto, M.

2016-02-01

Offshore renewable energy installations convert wave or wind energy to electricity and transfer the power to shore through transmission cables laid on or buried beneath the seafloor. West coast commercial fishermen, who harvest the highly prized Dungeness crab (Metacarcinus magister) and the rock crab (Cancer spp.), are concerned that the interface of crabs and electromagnetic fields (EMF) from these cables will present an electrified fence on the seafloor that their target resource will not cross. Combined with the assistance of professional fishermen, submarine transmission cables that electrify island communities and offshore oil platforms in the eastern Pacific provide an opportunity to test the harvest of crab species across power transmission cables. In situ field techniques give commercial crab species a choice to decide if they will cross fully energized, EMF emitting, power transmission cables, in response to baited traps. Each independent trial is either one of two possible responses: the crab crosses the cable to enter a trap (1) or the crab does not cross the cable to enter a trap (0). Conditions vary among sample units by the following categorical, fixed factors (i.e., covariates) of cable structure (buried or unburied); direction of cable from crab position (west or east, north or south); time and season. A generalized linear model is fit to the data to determine whether any of these factors affect the probability of crabs crossing an energized cable to enter baited traps. Additionally, the experimental design, aside from the number of runs (set of sample trials) and the dates of the runs, is the same in the Santa Barbara Channel for rock crab and Puget Sound for Dungeness crab, and allows us to compare the capture rates of the two species in the two areas. We present preliminary results from field testing in 2015.

Assessing potential impacts of energized submarine power cables on crab harvests

Science.gov (United States)

Love, Milton S.; Nishimoto, Mary M.; Clark, Scott; McCrea, Merit; Bull, Ann Scarborough

2017-12-01

Offshore renewable energy facilities transmit electricity to shore through submarine power cables. Electromagnetic field emissions (EMFs) are generated from the transmission of electricity through these cables, such as the AC inter-array (between unit) and AC export (to shore) cables often used in offshore energy production. The EMF has both an electric component and a magnetic component. While sheathing can block the direct electric field, the magnetic field is not blocked. A concern raised by fishermen on the Pacific Coast of North America is that commercially important Dungeness crab (Metacarcinus magister Dana, 1852)) might not cross over an energized submarine power cable to enter a baited crab trap, thus potentially reducing their catch. The presence of operating energized cables off southern California and in Puget Sound (cables that are comparable to those within the arrays of existing offshore wind energy devices) allowed us to conduct experiments on how energized power cables might affect the harvesting of both M. magister and another commercially important crab species, Cancer productus Randall, 1839. In this study we tested the questions: 1) Is the catchability of crabs reduced if these animals must traverse an energized power cable to enter a trap and 2) if crabs preferentially do not cross an energized cable, is it the cable structure or the EMF emitted from that cable that deters crabs from crossing? In field experiments off southern California and in Puget Sound, crabs were given a choice of walking over an energized power cable to a baited trap or walking directly away from that cable to a second baited trap. Based on our research we found no evidence that the EMF emitted by energized submarine power cables influenced the catchability of these two species of commercially important crabs. In addition, there was no difference in the crabs' responses to lightly buried versus unburied cables. We did observe that, regardless of the position of the cable

Optimized and practical electrical joints for CORC type HTS cables

CERN Document Server

Mulder, T; van der Laan, D C; Mentink, M G T; Dhallé, M; ten Kate, H H J

2015-01-01

Within CERN the development of REBCO-CORC (Conductor On Round Core) type cables is pursued in view of possible application in future detector and accelerator magnets. An important issue is the design and qualification of terminations for connecting CORC cables mutually or to bus-bars. A termination design is envisaged that combines a simple manufacturing process with a lowest possible joint terminal resistance in the few nΩ range at 4.2 K, first for a single CORC cable and subsequently for CORC based Cable-in-Conduit Conductors. The investigation concerns the effect of tapering the CORC cable within the joint to form a staircase like geometry, which allows current to pass more directly from the copper joint casing to the inner REBCO layers of the CORC cable. Simulations have shown a substantial decrease in joint resistance at operating current in the case both CORC cable and joint casing are tapered. The CORC cable and new joint were tested at CERN. In this paper, some details of the new joint design, fabric...

Optimized and practical electrical joints for CORC type HTS cables

International Nuclear Information System (INIS)

Mulder, T; Dudarev, A; Mentink, M G T; Ten Kate, H H J; Van der Laan, D C; Dhallé, M

2015-01-01

Within CERN the development of REBCO-CORC (Conductor On Round Core) type cables is pursued in view of possible application in future detector and accelerator magnets. An important issue is the design and qualification of terminations for connecting CORC cables mutually or to bus-bars. A termination design is envisaged that combines a simple manufacturing process with a lowest possible joint terminal resistance in the few nΩ range at 4.2 K, first for a single CORC cable and subsequently for CORC based Cable-in-Conduit Conductors. The investigation concerns the effect of tapering the CORC cable within the joint to form a staircase like geometry, which allows current to pass more directly from the copper joint casing to the inner REBCO layers of the CORC cable. Simulations have shown a substantial decrease in joint resistance at operating current in the case both CORC cable and joint casing are tapered. The CORC cable and new joint were tested at CERN. In this paper, some details of the new joint design, fabrication process, and model are presented and the results are summarized. (paper)

Security television monitoring using a wideband radio-frequency cable system

International Nuclear Information System (INIS)

Russell, J.A.; Case, A.L.; Crutcher, R.I.; Wetzell, F.E.

1981-01-01

The Oak Ridge National Laboratory (ORNL) was equipped with a multichannel, bidirectional rf cable television system for security assessment. The multichannel cable system was selected over a more conventional video cable system that has separate cables to each camera. Primary considerations for election of the rf cable system were initial cost and ease of midification or additions to the system. Two, 300-MHz cables, having a capacity of approx. 60 channels, and modulators and demodulators for 40 channels were installed. The modulators, located in buildings or building complexes, receive video signals from 40 TV cameras. These signals are transmitted as rf signals by the cable system to centralized emergency control center (ECC) where they are demodulated, processed, and displayed by the video equipment. TV monitors, digital video motion detectors, and recorders enable the dispatcher in the ECC to evaluate and document the video information. This paper covers the justification for a TV system and the reasons for selecting an rf cable system. It includes a discussion of the design criteria, installation, and expansion capabilities of the system

The Offshore Wind Farm Array Cable Layout Problem

DEFF Research Database (Denmark)

Bauer, Joanna; Lysgaard, Jens

2014-01-01

In an offshore wind farm (OWF), the turbines are connected to a transformer by cable routes that cannot cross each other. Finding the minimum cost array cable layout thus amounts to a vehicle routing problem with the additional constraints that the routes must be embedded in the plane. For this p......In an offshore wind farm (OWF), the turbines are connected to a transformer by cable routes that cannot cross each other. Finding the minimum cost array cable layout thus amounts to a vehicle routing problem with the additional constraints that the routes must be embedded in the plane....... For this problem, both exact and heuristic methods are of interest. We optimize cable layouts for real-world OWFs by a hop-indexed integer programming formulation, and develop a heuristic for computing layouts based on the Clarke and Wright savings heuristic for vehicle routing. Our heuristic computes layouts...... on average only 2% more expensive than the optimal layout. Finally, we present two problem extensions arising from real-world OWF cable layouts, and adapt the integer programming formulation to one of them. The thus obtained optimal layouts are up to 13% cheaper than the actually installed layouts....

Application and research of recyclable cables in foundation pit support engineering

Science.gov (United States)

Zheng, Suping

2018-05-01

Anchoring cables are widely used in the construction of foundation pit as a temporary support structure. After the construction is completed, the anchor cables left in the ground will not only cause environmental pollution but also cause a great waste of resources. The emergence of recyclable cable technology, to avoid such problems, to achieve the secondary use of the anchor cable, excavation in the excavation project is more and more widely used. Combined with the design and construction of recoverable anchor cable in engineering practice, the application effect of recoverable anchor cable in foundation pit support is analyzed, and the conclusion that the support effect of recoverable anchor cable is stable and safe can be obtained Recyclable anchor cable in the future support projects to provide a reference.

MVAC Submarine cable, magnetic fields measurements and analysis

DEFF Research Database (Denmark)

Arentsen, Martin Trolle; Expethit, Adrian; Pedersen, Morten Virklund

2017-01-01

Standard 60287. Researchers believe that the wire armour of three phased submarine cables is the reason for the inaccurate calculations by the standard. Studies show that the magnetic behaviour of these cables are changed due to the wire armour. In order to investigate this hypothesis, this paper intends...... to supply the theoretical research with data from magnetic field measurements on a wire armoured 3-phase submarine cable, together with an investigation of the induced currents in the different cable components. The influence of the physical arrangement of the armour wires on the electric behaviour is also...... investigated, since several researchers believe that the twisting of the armour wires result in zero net induced voltage over one helix length. This is shown to be valid for the tested cable. Finally a replica of the armour has been built with just a single conductor in the centre. This setup was used...

Ground Loop Impedance of Long EHV Cable Lines

DEFF Research Database (Denmark)

Ohno, Teruo; Bak, Claus Leth; Sørensen, Thomas K.

2012-01-01

The distance protection scheme without communication is often applied to the backup protection of EHV cable lines. For a reliable operation of a ground distance relay, the ground loop impedance of EHV cable lines needs to have a linear relationship to the distance from the relay location...... to the fault location. The discontinuity of the ground loop impedance at cross-bonding points may have an ill effect on the reliable operation of the ground distance relay. However, the cause and parameters of the discontinuity and its effects on the ground distance relay protection have not been discussed...... in literature. Through the calculation of the ground loop impedance for cable lines, it has been found that, for long EHV cable lines, the reliable operation of the ground distance relay is possible with a typical relay setting. Effects of parameters, such as substation grounding, cable layouts...

Life-assessment technique for nuclear power plant cables

International Nuclear Information System (INIS)

Bartonicek, B.; Hnat, V.; Placek, V.

1998-01-01

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

An Acoustic Source Reactive to Tow Cable Strum

Science.gov (United States)

2012-09-21

sound wave radiates from the head mass. Dkt . No. 101720 Application No. ?? REPLACEMENT SHEET? /3 DRAFT 1 CABLE CURVATURE INDUCING LONGITUDINAL...MOTION IDEALIZED TOW CABLE (NO TRANSVERSE VIBRATION) REALISTIC TOW CABLE (INCLUDES TRANSVERSE VIBRATION) DIRECTION OF TOW FIG. 1 (PRIOR ART) Dkt . No...DISPLACEMENT DISPLACEMENT LONGITUDINAL (PRIOR ART) DISPLACEMENT LONGITUDINAL Dkt . No. 101720 Application No. ?? REPLACEMENT SHEET? /3 DRAFT 10 A B B A

Wide-band cable systems at SLAC

International Nuclear Information System (INIS)

Struven, W.

1983-01-01

SLAC's first cable TV system was installed in 1979 to remotely monitor a narrow pulse which was generated in the west end of the klystron gallery. When Stanford Linear Collider (SLC) experimental work started at the west end of the accelerator, the original 1979 cable was upgraded to a bidirectional system so that 2 MBaud point-to-point data and several video and 9600 baud channels could be transmitted. The implementation of the SLC requires a complete upgrading of the accelerator control system. The system is based on a distributed processing configuration using a PDP11/780 VAX in the Main Control Center (MCC) and Intel single-board computers in a multibus configuration along the accelerator. The high-speed data linking is supplied by a 1 MBaud Time Division Multiple Access (TDMA) Network. The same cable is used to provide video, low-speed data, voice and high-speed point-to-point data services. The transmission system will utilize a wideband midsplit cable facility to collect and distribute signals to all parts of the network

MR damping system on Dongting Lake cable-stayed bridge

Science.gov (United States)

Chen, Z. Q.; Wang, X. Y.; Ko, J. M.; Ni, Y. Q.; Spencer, Billie F., Jr.; Yang, G.

2003-08-01

The Dongting Lake Bridge is a cable-stayed bridge crossing the Dongting Lake where it meets the Yangtze River in southern central China. After this bridge was completed in 1999, its cables were observed to be sensitive to rain-wind-induced vibration, especially under adverse weather conditions of both rain and wind. To investigate the possibility of using MR damping systems to reduce cable vibration, a joint project between the Central South University of China and the Hong Kong Polytechnic University was conducted. Based on the promising research results, the bridge authority decided to install MR damping systems on the longest 156 stay cables. The installation started in July 2001 and finished in June 2002, making it the world's first application of MR dampers on cable-stayed bridge to suppress the rain-wind-induced cable vibration. As a visible and permanent aspect of bridge, the MR damping system must be aesthetically pleasing, reliable, durable, easy to maintain, as well as effective in vibration mitigation. Substantial work was done to meet these requirements. This paper describes the implementation of MR damping systems for cable vibration reduction.

Design guide for fire protection of grouped electrical cables

International Nuclear Information System (INIS)

Dungan, K.W.

1991-05-01

This paper develops design guidance for fire protection of grouped electrical cables using previous research and the concept of design objectives based on damage limits. A quantitative approach is taken to establishing performance-oriented design objectives and addressing fires exposing cables as well as cable fires. A one-page Design Calculation Checklist is developed and examples are shown. In addition, testing was done for placement of linear thermal detection on cable trays and recommendations are given. 32 refs., 10 figs., 8 tabs

A simulated-annealing-based approach for wind farm cabling

NARCIS (Netherlands)

Lehmann, S.; Rutter, I.; Wagner, D.; Wegner, F.

2017-01-01

We study the problem of computing a wind farm cabling with minimum costs allowing different cable types. Our model distinguishes different levels of granularity, where the highest level represents the cabling problem for the whole wind farm. Since even the most restricted of these problems is

Continuous operation of NPP Kori Unit 1 - Fireproof paint for cables

International Nuclear Information System (INIS)

Wendt, Dipl-Ing. Ruediger; Kim, Duill; Sik, Cho Hong

2008-01-01

Fireproof cable coating materials have been used in European NPP, especially in Germany, Russia, Ukraine, Czech Republic, Lithuania, Switzerland. Wide experiences were made during operation while applying these systems. In NPP Kori, Unit 1, a fire proof cable coating project was realised for the first time in a NPP of KHNP. The scope of services of the cable trays to coat amounts to 15,587m 2 . In different fire compartments and rooms the cables should be coated partially respectively completely with the fire proof cable coating system. The extent of cable surfaces to coat was stipulated by KHNP on the basis of an analysis made by KHNP. The project was tendered on the basis of a technical specification of KHNP. The specification is mainly predicted on Korean and US standards. The most important criteria for the fire proof cable coating is resumed as follows: The fireproof cable coating has to assure the fire protection of the cables for a period defined and for operational conditions defined in such a manner that the general conditions for the operation of the cable installation will not be affected

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...

An ACLU Guide to Cable Television.

Science.gov (United States)

Powledge, Fred

Proceeding from the hypothesis that cable television (CATV) is one of the most significant developments in modern America, this booklet examines the medium itself and then devotes special attention to the capacity of CATV to serve the First Amendment interest in diversity of expression. The opening section deals with the size and growth of cable,…

Cable Television: The Process of Franchising.

Science.gov (United States)

Johnson, Leland L.; Botein, Michael

In an effort to insure that cable television franchising procedures at the local level are based on a competitive and well-conceived selection process, this report discusses some of the most important steps of the franchising process. Not only does it show how the community should assess its needs and appraise the merits of the cable operator, but…

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.

7 CFR 1755.870 - RUS specification for terminating cables.

Science.gov (United States)

2010-01-01

... core wrap. (f) Shield. (1) An aluminum shield, plastic coated on one side, shall be applied... section establishes the requirements for terminating cables used to connect incoming outside plant cables... cylindrical core. (iii) The cable structure is completed by the application of a core wrap, a shield, and a...

30 CFR 75.817 - Cable handling and support systems.

Science.gov (United States)

2010-07-01

... High-Voltage Longwalls § 75.817 Cable handling and support systems. Longwall mining equipment must be provided with cable-handling and support systems that are constructed, installed and maintained to minimize... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Cable handling and support systems. 75.817...

Structured Cable for High-Current Coils of Tokamaks

Science.gov (United States)

Benson, Christopher; McIntyre, Peter; Sattarov, Akhdiyor; Mann, Thomas

2011-10-01

The 45 kA superconducting cable for the ITER central solenoid coil has yielded questionable results in two recent tests. In both cases the cable Tc increased after cycling only a fraction of the design life, indicating degradation due to fatigue and fracture among the superconducting strands. The Accelerator Research Lab at Texas A&M University is developing a design for a Nb3Sn structured cable suitable for such tokamak coils. The superconductor is configured in 6 sub-cables, and each subcable is supported within a channel of a central support structure within a high-strength armor sheath. The structured cable addresses two issues that are thought to compromise opposition at high current. The strands are supported without cross-overs (which produce stress concentration); and armor sheath and core structure bypass stress through the coil and among subcables so that the stress within each subcable is only what is produced directly upon it. Details of the design and plans for development will be presented.

An enhanced fire hazard assessment model and validation experiments for vertical cable trays

International Nuclear Information System (INIS)

Li, Lu; Huang, Xianjia; Bi, Kun; Liu, Xiaoshuang

2016-01-01

Highlights: • An enhanced model was developed for vertical cable fire hazard assessment in NPP. • The validated experiments on vertical cable tray fires were conducted. • The capability of the model for cable tray with different cable spacing were tested. - Abstract: The model, referred to as FLASH-CAT (Flame Spread over Horizontal Cable Trays), was developed to estimate the heat release rate for vertical cable tray fire. The focus of this work is to investigate the application of an enhanced model to the single vertical cable tray fires with different cable spacing. The experiments on vertical cable tray fires with three typical cable spacing were conducted. The histories of mass loss rate and flame length were recorded during the cable fire. From the experimental results, it is found that the space between cable lines intensifies the cable combustion and accelerates the flame spread. The predictions by the enhanced model show good agreements with the experimental data. At the same time, it is shown that the enhanced model is capable of predicting the different behaviors of cable fires with different cable spacing by adjusting the flame spread speed only.

An enhanced fire hazard assessment model and validation experiments for vertical cable trays

Energy Technology Data Exchange (ETDEWEB)

Li, Lu [Sate Key Laboratory of Fire Science, University of Science and Technology of China, Hefei 230027 (China); Huang, Xianjia, E-mail: huangxianjia@gziit.ac.cn [Joint Laboratory of Fire Safety in Nuclear Power Plants, Institute of Industry Technology Guangzhou & Chinese Academy of Sciences, Guangzhou 511458 (China); Bi, Kun; Liu, Xiaoshuang [China Nuclear Power Design Co., Ltd., Shenzhen 518045 (China)

2016-05-15

Highlights: • An enhanced model was developed for vertical cable fire hazard assessment in NPP. • The validated experiments on vertical cable tray fires were conducted. • The capability of the model for cable tray with different cable spacing were tested. - Abstract: The model, referred to as FLASH-CAT (Flame Spread over Horizontal Cable Trays), was developed to estimate the heat release rate for vertical cable tray fire. The focus of this work is to investigate the application of an enhanced model to the single vertical cable tray fires with different cable spacing. The experiments on vertical cable tray fires with three typical cable spacing were conducted. The histories of mass loss rate and flame length were recorded during the cable fire. From the experimental results, it is found that the space between cable lines intensifies the cable combustion and accelerates the flame spread. The predictions by the enhanced model show good agreements with the experimental data. At the same time, it is shown that the enhanced model is capable of predicting the different behaviors of cable fires with different cable spacing by adjusting the flame spread speed only.

Single cables for nuclear instrumentation : Experiences at TAPS

International Nuclear Information System (INIS)

Chalam, K.V.; Joshi, S.V.

1977-01-01

For fast response and good accuracy, cables of special type are required to be interposed between radiation detectors and preamplifiers/ monitors in a nuclear reactor. The essential characteristics which these signal cables must possess and the tests which they have to undergo are enumerated. Signal cables used in various individual neutron monitoring systems at the Tarapur Atomic Power Station are described in detail. The systems considered are : (1) source range monitoring systems, (2) intermediate range monitoring system, (3) power range monitoring systtem, (4) local power range monitoring system, (5) traversing in-core probe system and (6) area radiation monitoring system. Experience with signal cabling during power operation is given. (M.G.B.)

30 CFR 75.600-1 - Approved cables; flame resistance.

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Approved cables; flame resistance. 75.600-1 Section 75.600-1 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE... cables; flame resistance. Cables shall be accepted or approved by MSHA as flame resistant. [57 FR 61223...

Cable Television: Technical Considerations in Franchising Major Market Systems.

Science.gov (United States)

Pilnick, Carl

The 1972 Federal Communications Commission's (FCC) regulations on cable television were intended to assist the penetration of cable television into the large metropolitan regions of the United States. In these major market areas, the task for developing an appropriate franchise is complicated by the changing functional nature of the cable systems…

SSC 40 mm cable results and 50 mm design discussions

International Nuclear Information System (INIS)

Christopherson, D.; Capone, D.; Hannaford, R.; Remsbottom, R.; Delashmit, R.; Jayakumar, R.J.; Snitchler, G.; Scanlan, R.; Royet, J.

1991-01-01

This paper presents a summary of the cable produced for the 1990 40 mm Dipole Program. The cable design parameters for the 50 mm Dipole Program are discussed, as well as portions of the SSC specification draft. Considerations leading to the final cable configuration and the results of preliminary trials are included. The first iteration of a strand mapping program to automate cable strand maps is introduced

Cable Television and Educational Access: A Reconsideration.

Science.gov (United States)

Thornton, Lee R.; Greene, James C.

1986-01-01

Considers the possible impact of recent federal legislation on educational utilization of cable television. Stresses the importance of educators understanding the law's provisions and acting to initiate relationships with cable companies. Reviews public educational or governmental access provisions. Presents strategies for promoting reciprocity…

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.

Experimental characterization of shape memory alloy actuator cables

Science.gov (United States)

Biggs, Daniel B.; Shaw, John A.

2016-04-01

Wire rope (or cables) are a fundamental structural element in many engineering applications. Recently, there has been growing interest in stranding NiTi wires into cables to scale up the adaptive properties of NiTi tension elements and to make use of the desirable properties of wire rope. Exploratory experiments were performed to study the actuation behavior of two NiTi shape memory alloy cables and straight monofilament wire of the same material. The specimens were held under various dead loads ranging from 50 MPa to 400 MPa and thermally cycled 25 times from 140°C to 5°C at a rate of 12°C/min. Performance metrics of actuation stroke, residual strain, and work output were measured and compared between specimen types. The 7x7 cable exhibited similar actuation to the single straight wire, but with slightly longer stroke and marginally more shakedown, while maintaining equivalent specific work output. This leads to the conclusion that the 7x7 cable effectively scaled up the adaptive properties the straight wire. Under loads below 150 MPa, the 1x27 cable had up to double the actuation stroke and work output, but exhibited larger shakedown and poorer performance when loaded higher.

Real Time Load Optimisation of Cable Based Transmission Grids

DEFF Research Database (Denmark)

Olsen, Rasmus Schmidt; Holbøll, Joachim; Guðmundsdottir, Unnur Stella

2011-01-01

Energinet.dk has launched an investigation of dynamic current ratings of cable based transmission grids, where both internal and external parameters are variables. The first topic was to investigate state of the art within calculating the current carrying capacity (ampacity or loadability......) of cables embedded in larger cable systems. Some recently published research has been concerned with dynamic loadability, but such researches are based on many assumptions. It is shown in the paper, that only limited research has been concerned with larger cable grids, and no remarkable work could been...

Dynamics of a deep-sea cable system

International Nuclear Information System (INIS)

Gulyaev, V.I.; Koshkin, V.L.; Serpak, I.O.

1995-01-01

We consider the problem of the dynamics of a deep-sea cable system consisting of branches of constant and variable length, interacting with an undercurrent which is variable in depth and direction. We construct a mathematical model for the motion of the element of the cable system. The cables are modeled as inextensible, flexible filaments of variable length. For numerical realization of the problem, we suggest special regularizing transformations of the variables, making it possible (without additional simplifications) to take into account all the characteristic features of the motion of the filaments and to avoid difficulties in the integration of the equations of motion connected with the variability of the length of the branches of the cable system. The proposed mathematical model and the technique for its numerical analysis is applicable for the investigation of the dynamics of a complex for mining minerals from the ocean floor

Report on full-scale horizontal cable tray fire tests, FY 1988

International Nuclear Information System (INIS)

Riches, W.M.

1988-09-01

In recent years, there has been much discussion throughout industry and various governmental and fire protection agencies relative to the flammability and fire propagation characteristics of electrical cables in open cable trays. It has been acknowledged that under actual fire conditions, in the presence of other combustibles, electrical cable insulation can contribute to combustible fire loading and toxicity of smoke generation. Considerable research has been conducted on vertical cable tray fire propagation, mostly under small scale laboratory conditions. In July 1987, the Fermi National Accelerator Laboratory initiated a program of full scale, horizontal cable tray fire tests, in the absence of other building combustible loading, to determine the flammability and rate of horizontal fire propagation in cable tray configurations and cable mixes typical of those existing in underground tunnel enclosures and support buildings at the Laboratory. The series of tests addressed the effects of ventilation rates and cable tray fill, fire fighting techniques, and effectiveness and value of automatic sprinklers, smoke detection and cable coating fire barriers in detecting, controlling or extinguishing a cable tray fire. This report includes a description of the series of fire tests completed in June 1988, as well as conclusions reached from the test results

Guy cable design and damping for vertical axis wind turbines

Science.gov (United States)

Carne, T. G.

1981-01-01

Guy cables are frequently used to support vertical axis wind turbines since guying the turbine reduces some of the structural requirements on the tower. The guys must be designed to provide both the required strength and the required stiffness at the top of the turbine. The axial load which the guys apply to the tower, bearings, and foundations is an undesirable consequence of using guys to support the turbine. Limiting the axial load so that it does not significantly affect the cost of the turbine is an important objective of the cable design. The lateral vibrations of the cables is another feature of the cable design which needs to be considered. These aspects of the cable design are discussed, and a technique for damping cable vibrations was mathematically analyzed and demonstrated with experimental data.

Characteristics of the joint mini-model high temperature superconducting cable

International Nuclear Information System (INIS)

Kim, H.; Sim, K.; Cho, J.; Kim, S.; Kim, J.H.; Jung, H.Y.

2008-01-01

To obtain realistic data on the high temperature superconducting (HTS) power cable, 3-phase 100 m long, 22.9 kV class HTS power transmission cable system have been developed by Korea Electrotechnology Research Institute (KERI) and LS cable Ltd. that is one of 21st Century Frontier Project in Korea. This cable was installed at Go-chang testing site of Korea Electric Power Corporation (KEPCO). For the application of the HTS power cable joint is very important to ensure the performance. Therefore, this paper gives some investigation of AC loss, critical current and joint resistance in jointed HTS tape. We experimentally showed that the influence of joint resistance on AC loss by using several joint methods. Finally, we are measured critical current, AC loss and jointed resistance for the manufactured mini-model cable

75 FR 61116 - Refunds Under the Cable Statutory License

Science.gov (United States)

2010-10-04

... Copyright Act, before it was amended to allow a cable system to calculate its royalty fees on a community-by... statutory license set forth in Section 111 are required to pay royalty fees to the Copyright Office... the methodology for a cable operator to calculate royalty fees. Cable operators now pay royalty fees...

Nuclear instrumentation cable end seal

International Nuclear Information System (INIS)

Cannon, C.P.; Brown, D.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 is described. 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

Statistical analysis of aging trend of mechanical properties in ethylene propylene rubber-insulated safety-related cables sampled from containments (Denryoko Chuo Kenkyusho Hokoku, December 2013 issue)

International Nuclear Information System (INIS)

Fuse, Norikazu; Kanegami, Masaki; Misaka, Hideki; Homma, Hiroya; Okamoto, Tatsuki

2013-01-01

As for polymeric insulations used in nuclear power plant safety cables, it is known that the present prediction model sometimes estimates the service life conservatively. In order to sophisticate the model to reflect to the aging in containments, disconnections between the prediction and realities are needed to be clarified. In the present paper, statistical analysis has been carried out on various aging status of insulations removed from domestic containments. Aging in operational environment is found to be slower than the one expected from acceleration aging test results. Temperature dependence of estimated lifetime on Arrhenius plot also suggests that elementary chemical reaction dominant under the two aging conditions is different, which results in apparent difference in activation energies and pre-exponential factors. Following two kinds of issues are found necessary to be clarified for the model sophistication; temperature change in predominant degradation chemical processes, and the effect of low oxygen concentration environment in boiling water reactor type containment. (author)

Análisis de falla en cable de acero Análisis de falla en cable de acero

Directory of Open Access Journals (Sweden)

E. A. Ossa

2005-12-01

Full Text Available Este artículo describe el análisis de falla realizado en dos muestras de cables de acero que sufrieron falla súbita bajo condiciones de carga de trabajo normales. La falla fue causada por una carga menor a la capacidad nominal. Luego de inspección óptica se evidenció que la falla fue ocasionada por fatiga del material de uno de los cables.This paper describes the failure analysis of two wire ropes fractured during normal working conditions. The failure was caused by a load well below the nominal maximum resistance of the ropes. Optical microscopy indicated fatigue failure of one of the cables.

30 CFR 77.600 - Trailing cables; short-circuit protection; disconnecting devices.

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Trailing cables; short-circuit protection... AREAS OF UNDERGROUND COAL MINES Trailing Cables § 77.600 Trailing cables; short-circuit protection; disconnecting devices. Short-circuit protection for trailing cables shall be provided by an automatic circuit...

7 CFR 1755.902 - Minimum performance Specification for fiber optic cables.

Science.gov (United States)

2010-01-01

... installation provided by the end user, the manufacturer must provide a cable design with sag and tension tables... cables. 1755.902 Section 1755.902 Agriculture Regulations of the Department of Agriculture (Continued... optic cables. (a) Scope. This section is intended for cable manufacturers, Agency borrowers, and...

Design, analysis and control of cable-suspended parallel robots and its applications

CERN Document Server

Zi, Bin

2017-01-01

This book provides an essential overview of the authors’ work in the field of cable-suspended parallel robots, focusing on innovative design, mechanics, control, development and applications. It presents and analyzes several typical mechanical architectures of cable-suspended parallel robots in practical applications, including the feed cable-suspended structure for super antennae, hybrid-driven-based cable-suspended parallel robots, and cooperative cable parallel manipulators for multiple mobile cranes. It also addresses the fundamental mechanics of cable-suspended parallel robots on the basis of their typical applications, including the kinematics, dynamics and trajectory tracking control of the feed cable-suspended structure for super antennae. In addition it proposes a novel hybrid-driven-based cable-suspended parallel robot that uses integrated mechanism design methods to improve the performance of traditional cable-suspended parallel robots. A comparative study on error and performance indices of hybr...

Recent development of the Cu/Nb-Ti superconducting cables for SSC in Hitachi Cable, Ltd

International Nuclear Information System (INIS)

Sakai, S.; Iwaki, G.; Sawada, Y.; Moriai, H.; Ishigami, Y.

1989-01-01

In these few years, Cu/Nb-Ti superconducting cables for the dipole magnets of SSC projects have been developed in the industrial scale in Hitachi Cable, Ltd. The features of these developed conductors are as follows. (1) The diameter of Nb-Ti filaments is very small, 4-6 μm. (2) The critical current density (J c ) is very high, 2,850-3,050 A/mm 2 at 5 T on wires, 2750-2950 A/mm 2 at 5 T on cables in industrial scale. The champion J c of wires is 3,460 A/mm 2 at 5 T in the laboratory scale. (3) The RRR Residual Resistivity Ratio values of developed cables is very high, approximately 200, due to the newly developed high purity Oxygen Free Copper (OFC). (4) The conductors have been wound to the 1 m length dipole magnet in Hitachi Ltd., and it has generated 6.7 T in the central magnetic field at 6,595 A. The Cu/Cu-Mn/Nb-Ti composite wires which avoid the possibility of electrical coupling of the filaments have been produced in laboratory scale. The RRR of the copper stabilizer and J c properties have not degraded because of no metallurgical reactions between Cu and Mn, Nb-Ti and Mn. 7 refs., 9 figs., 4 tabs

Cable Television 1980: Status and Prospect for Higher Education.

Science.gov (United States)

Baus, F., Ed.

Baseline information for the would-be cable television educational programer is provided by two papers, one an overview of the state of the cable television industry, and the other a report on a marketing study conducted to determine consumer attitudes toward cable TV as an educational medium. In "The Promise and Reality of Cable…

Development of non-halogen cables for nuclear power stations

Energy Technology Data Exchange (ETDEWEB)

Yagyu, Hideki; Yamamoto, Yasuaki; Onishi, Takao (Hitachi Cable, Ltd., Tokyo (Japan))

1983-12-01

The non-halogen fire-resistant cables for nuclear power stations which never generate halogen gas, have been developed. The cables comprise the insulator of EP rubber and the sheath of polyolefine containing non-halogen inorganic fire-retardant. The results of the environmental test and fire-resistance test are described. In the environmental test, the cables were subjected to the heating, gamma-irradiation and steam exposure successively, according to IEEE specification 323,383, and subsequently the change in the appearance, tensile strength and electrical performance of the cables was measured. In the fire-resistance test, the vertical tray fire test according to the IEEE specification 383 was adopted, and other tests including the vertical fire test on insulator cores, oxygen index, the generation of corrosive gas, copper mirror corrosion test, gas toxicity test and optical smoke density test were carried out. It became clear that the cables did not generate halogen gas on burning, and brought about reduced toxicity, corrosion and smoke, and that the safety against fire is greatly improved by using the cables.

Development of non-halogen cables for nuclear power stations

International Nuclear Information System (INIS)

Yagyu, Hideki; Yamamoto, Yasuaki; Onishi, Takao

1983-01-01

The non-halogen fire-resistant cables for nuclear power stations which never generate halogen gas, have been developed. The cables comprise the insulator of EP rubber and the sheath of polyolefine containing non-halogen inorganic fire-retardant. The results of the environmental test and fire-resistance test are described. In the environmental test, the cables were subjected to the heating, gamma-irradiation and steam exposure successively, according to IEEE specification 323,383, and subsequently the change in the appearance, tensile strength and electrical performance of the cables was measured. In the fire-resistance test, the vertical tray fire test according to the IEEE specification 383 was adopted, and other tests including the vertical fire test on insulator cores, oxygen index, the generation of corrosive gas, copper mirror corrosion test, gas toxicity test and optical smoke density test were carried out. It became clear that the cables did not generate halogen gas on burning, and brought about reduced toxicity, corrosion and smoke, and that the safety against fire is greatly improved by using the cables. (Yoshitake, I.)

Rapid cable tension estimation using dynamic and mechanical properties

Science.gov (United States)

Martínez-Castro, Rosana E.; Jang, Shinae; Christenson, Richard E.

2016-04-01

Main tension elements are critical to the overall stability of cable-supported bridges. A dependable and rapid determination of cable tension is desired to assess the state of a cable-supported bridge and evaluate its operability. A portable smart sensor setup is presented to reduce post-processing time and deployment complexity while reliably determining cable tension using dynamic characteristics extracted from spectral analysis. A self-recording accelerometer is coupled with a single-board microcomputer that communicates wirelessly with a remote host computer. The portable smart sensing device is designed such that additional algorithms, sensors and controlling devices for various monitoring applications can be installed and operated for additional structural assessment. The tension-estimating algorithms are based on taut string theory and expand to consider bending stiffness. The successful combination of cable properties allows the use of a cable's dynamic behavior to determine tension force. The tension-estimating algorithms are experimentally validated on a through-arch steel bridge subject to ambient vibration induced by passing traffic. The tension estimation is determined in well agreement with previously determined tension values for the structure.

Life estimation I and C cable insulation materials based on accelerated life testing accelerated life testing

International Nuclear Information System (INIS)

Santhosh, T.V.; Ramteke, P.K.; Shrestha, N.B.; Ahirwar, A.K.; Gopika, V.