R&D Category: Thermo mechanical properties of systems during normal and beyond-design operating regimes and materials science
36 documents found
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About the behavior of Zirconium hydride solid bodies under reactor irradiation Ueber das Verhalten von Zirkonhydridmassivkoerpern unter Reaktorbestrahlung
Greiner, L.;Paetz, P.;Staubwasser, WINTERATOM GmbH, Bergisch-Gladbach (Germany)
IA-INTAT--35 - German - 1965
Abstract: This report documents the irradiation of Zirconium hydride samples produced by INTERATOM in the GETR of the General Electric Company. The material had the form of discs and cylinders and was irradiated with a neutron fluence of 1021 nvt (En
Key words: getr reactor;irradiation;knk-2 reactor;metallography;microhardness;microstructure;moderators;neutron fluence;radiation effects;temperature range 0400-1000 k;zirconium hydrides
Components Category: -Core components
display the document: 34087401.pdf
Development work for the moderator of the ITR-fuel Entwicklungsarbeiten zum ITR-Brennstoff-Moderator
Duenner, P.;Becker, DINTERATOM GmbH, Bergisch-Gladbach (Germany)
IA-ITB--73.42 - German - 1973
Abstract: In the frame of the ITR-project (Incore-Thermionic-Reactor) fuel-moderator-materials had been investigated, which are also of interest for the KNK-project and which are therefore documented in this report. Partial pressure measurements on the systems Zr-H, Zr U-H, Y-H and YH-H revealed the premise for the elaboration of a hydration technique. On the basis of the functional relation between partial H2-pressure, temperature and H2-content of the hydride, an optimum hydration kinetic for the production of flawless and well defined hydrated Zirconium hydride/Uranium pellets and of Zirconium hydride and Yttrium hydride moderator bodies was developed. Alternatively to the ZrHx-U-technology a powder- metallurgical procedure for the production of a Y-U sinter-alloy as base material was tested. In an irradiation experiment in the DIDO reactor (in Juelich) the burnup behavior of Zirconium hydride-Uranium and Yttrium hydride-Uranium under ITR-similar conditions has been tested. With a U235-burnup of 6.75 % and an irradiation temperature of 490 deg C a fission gas release rate of 0.1 % was observed. The ZrHx-pellets remained mechanically intact, whereas the YHx-pellets crumbled during the post-examinations. The ZrHx-U showed a maximum density reduction of 4.2 %
Key words: burnup;dido reactor;fission product release;fuel pellets;hydration;irradiation;knk-2 reactor;materials testing;thermionic reactors;uranium;yttrium hydrides;zirconium hydrides
Components Category: --Fuel matrices
display the document: 34087419.pdf
Operating experience and design criteria of sodium valves
Markford, D. (INTERATOM, Bensberg, Ger.)CONF-740964-- - English - 1974
Abstract: The information presented refers to sodium valve development for KNK and SNR-300 as well as for sodium test facilities on the INTERATOM site at Bensberg. Well in advance of KNK-I a number of sodium test facilities have been operated containing small and medium size valves of different design and manufacturer. The more stringent requirements for long range safe and reliable operation in KNK-I put forth a development program for the main primary and secondary circuit sodium valves. Operational experience gave rise to modification of the stem seal arrangement mainly, so KNK-II (which is the fast core for KNK reactor) will be run with modified sodium valves. Main pipe diameters in SNR-300 are in the range of 600 mm. Valve designs with rising shafts would require excessive space in the primary circuit cavities, therefore efforts have been directed towards introduction of different type valves. Due to the requirements of after-heat-removal a valve type with control capability had to be chosen. A special design of butterfly valves was selected for the primary and secondary circuits of SNR-300. The development and tests performed with this type of valve are described. In the field of small sodium valves, tests with a 50 mm diameter freeze-seal valve are reported, and the current status of bellows-seal-valves to be inserted into SNR-300 is discussed. (U.S.)
Key words: knk reactor;knk-2 reactor;performance;reactor cooling systems;snr reactor;sodium;valves
Components Category: --Piping, elbows, valves
display the document: 06201858.pdf
Influence of fuel pin bowing on the temperature distribution in fuel pin cladding tubes in case of sodium cooling. Experimental results Einfluss der Stabverbiegung auf die Temperaturverteilung in Brennstabhuellrohren bei Natriumkuehlung - Experimentelle Ergebnisse -
Moeller, R.;Tschoeke, H.;Kolodziej, MKernforschungszentrum Karlsruhe GmbH (Germany)
KFK-PSB--01.02.23P01D - German - 1978
Abstract: The influence of rod bowing on the local temperature distribution was measured with turbulent sodium flow in the cladding tubes of a 19-rod bundle mock-up of the SNR 300 Mark Ia fuel element. Such measurements have been carried out for the first time. The results presented in this report are part 1 of the experimental evaluation not yet completed. The major results are: 1. When a rod on the first ring gets deformed towards a neighbour on the second ring with a gap reduction from the nominal value of 100 % down to 20 %, the maximum azimuthal temperature difference of the outer rod increases by about 60 %. 2. The maximum azimuthal temperature difference of a rod on the first ring increases by a factor of 2, if it is approached by a neighbour on the same ring. 3. The reduction in cross section of a subchannel by rod bowing results only locally in distinct temperature rises, i.e. in the adjacent cladding tubes. Rods of the next but one row are no more subject to noticeable changes in temperature
Key words: bowing;deformation;design;fuel assemblies;knk-2 reactor;sodium;temperature distribution;testing;thermal hydraulics;turbulent flow
Components Category: --Fuel pins
display the document: 34086298.pdf
The behavior of the fuel pins of the fuel element NY 205 of KNK II Zum Verhalten der Staebe des Brennelementes NY 205 aus der KNK II
Goetzmann, OKernforschungszentrum Karlsruhe GmbH (Germany)
KFK-PSB--01.11.03P02A - German - 1978
Abstract: The fuel element NY 205 has been irradiated in the first and in the second core of KNK II up to a maximum local burnup of 18.6 % with a total residence time of 832 equivalent full-power days and a maximum local steel damage of 66 dpa-NRT. Because of a fuel pin failure it was unloaded on May 28, 1987 and carried to the Hot Cells of the Karlsruhe Research Center. The results of the post-irradiation examinations and the conclusions to be drawn are described in this report. The pin claddings, made of the steels 1.4970 and 1.4980, experienced expansion due to swelling with maxima around or just below core mid-plane. The axial redistribution of volatile fission products lead to an accumulation in the upper third of the fissile column. In this area the inner clad corrosion was most intensive with a depth of up to 130
Key words: burnup;cladding;corrosion;fission products;fuel element failure;fuel pins;knk-2 reactor;performance testing;post-irradiation examination;spacers;swelling
Components Category: --Fuel assemblies
display the document: 34086301.pdf
The irradiation of carbide fuel pins in the frame of the Fast Breeder Project Die Bestrahlung von Karbid-Brennstaeben im Rahmen des PSB
Steiner, HKernforschungszentrum Karlsruhe GmbH (Germany)
KFK-PSB--01.03.03P23C - German - 1979
Abstract: The report gives an overview of the present status and the most important results of the carbide-program of the Fast Breeder Project PSB. Only integral fuel pin irradiation experiments are considered. The PSB-program is characterized by a plurality of parameter variations, partly within large ranges. The most important variations concern the concept of the bonding, the smear- and pellet-density, the fabricated gap width between fuel and cladding as well as the irradiation conditions for the pin power, cladding temperature and burnup. In view of the small number of test samples the inclusion of the international irradiation experience is a great advantage. The results with the gas-bonded fuel pins indicate, that the achievable burnup increases when the smear density is decreased from 85 % to 80 %. Burnups of 7 % and more together with linear powers of 800 - 1100 W/cm can only be reached with smear densities of 80 % or less. For sodium-bonded pins, the defect-rate is smaller than for gas-bonded pins. Out of the four observed defects two were caused by failures of the capsule and the others by excessive cladding carburization. Besides questions of concept valuation, the present report also discusses some important aspects of the irradiation behavior of carbide samples, such as thermal behavior and mechanical interaction between fuel and cladding and carburization
Key words: burnup;carburization;cladding;fuel pellets;irradiation;knk-2 reactor;mixed carbide fuels;physical radiation effects
Components Category: --Fuel and cladding
display the document: 34086300.pdf
Design of the grid-plate inserts of the second core of KNK II Auslegung der Gitterplatteneinsaetze fuer den zweiten Kern der KNK II (Bearbeitungsstand 02.81)
Schade, H.-JINTERATOM GmbH, Bergisch-Gladbach (Germany)
IA-INTAT--70.01654.9 - German - 1981
Abstract: The report describes the modified design of the grid plate inserts for the second core of KNK II together with the consequences of these changes on the plant. The changes due to the installation of special gas bubble separators in the 30 grid plate inserts of the sixth fuel element row have the goal to assure a plant operation, which is not disturbed by gas bubble transport through the core and the consequent reactivity effects. The detailed construction and the experimental verification of the concept are described. Further explanations are related to the thermal-hydraulic design of the second KNK II core with special consideration of the new flow scheme, to the reactivity behaviour of the core in case of gas bubble ingress and to the plant behaviour in case of disturbations, especially the emergency cooling situation. It is proved that the sufficient cooling of the core is guaranteed and that the safety degree of the plant is not deteriorated by the design modifications
Key words: bubbles;eccs;entrainment;fluid flow;fuel elements;knk-2 reactor;reactivity insertions;reactor operation;thermal hydraulics
Components Category: --Core structural materials
display the document: 34087405.pdf
KNK-II fuel elements and their operational behavior. Die Brennelemente der KNK-II und ihr Betriebsverhalten
Mayer, H. (Internationale Atomreaktorbau G.m.b.H. (INTERATOM), Bergisch Gladbach (Germany, F.R.));Richard, H. (Kernkraftwerk-Betriebsgesellschaft m.b.H., Eggenstein-Leopoldshafen (Germany, F.R.))KFK--3278 - German - 1982
Abstract: Design, fabrication, authorization for operation and the operation itself signify for the project partners involved the step from an research and development program to the procurment of a larger number of fuel subassemblies for a nuclear power plant. Although priority is given to operations experience, those assemblies have to be part of the long-term fuel development program. The first fast core of the KNK-II has reached a residence time of 273 efpd corresponding to a peak burnup of 65.000 MWd/tsub(HM) in 5 assemblies. By such, the originally planned target of 255 efpd has already been exceeded. The authorization for an operation up to 355 efpd has been granted. The extended periods of operation at 100% load as well as the reached burnup prove that the two fuel pin defects (in two assemblies one pin each) do not have any systematic origin. (orig.)
Key words: burnup;fuel element failure;fuel elements;fuel pins;knk-2 reactor;performance;reactor operation
Components Category: --Fuel assemblies
display the document: 13696676.pdf
Development of materials for higher burn-up rates. Werkstoffentwicklung fuer hoehere Abbraende
Ehrlich, K.;Anderko, K. (Kernforschungszentrum Karlsruhe G.m.b.H. (Germany, F.R.). Inst. fuer Material- und Festkoerperforschung 2 - Teilinstitut Huellwerkstoffe)KFK--3505 - German - 1983
Abstract: The results obtained so far concerning both high-nickel austenitic steels (X10CrNiMoTiB10 25) and ferritic-martensitic steels (X18CrMoVNb12 1 corresponds to 1.4914) justify the expectations placed in these materials. Future R and D work will concentrate on high-nickel austenitic steels, in particular on in-pile residence time in the range of maximum cladding mean temperatures (He embrittlement), on confirmation of the fairly good swelling and creep behaviour to be obtained from neutron irradiation experiments as well as on material qualification and technology. As far the development in the field of martensitic steels the major question concerns the influence of neutron irradiation on the transient temperature. It is just as important and interesting to detect and describe the ruling in-pile creep mechanism in the 400 to 6000C range. Furthermore, questions on the fabrication and qualification of cladding tube boxes are also preeminent. (orig.)
Key words: austenitic steels;burnup;fbr type reactors;fuel cans;knk-2 reactor;martensitic steels;reactor materials
Components Category: --Fuel and cladding
display the document: 15028667.pdf
Steady-state irradiation experiments. Stationaere Bestrahlungsexperimente
Geithoff, D. (Kernforschungszentrum Karlsruhe G.m.b.H. (Germany, F.R.). Inst. fuer Material- und Festkoerperforschung 3 - Teilinstitut Brennelemente)KFK--3505 - German - 1983
Abstract: This paper describes the steady-state irradiation experiments DFR-350, RAPSODIE-I and DFR-455 to be milestones in the development of the SNR Mk Ia fuel rod concept and also a number of relevant results. For the two defective fuel elements from the KNK-2 reactor, in particular for the BE 202 IA, the status of the fuel rods is described on the basis of results obtained at the various stages of post-irradiation examination. The comparison of these results with those from previous experiments shows the value of such results for these rods. Thus the fuel rod behaviour in different circumstances is evaluated in qualitative terms. (orig.)
Key words: fuel element failure;fuel pins;irradiation capsules;irradiation devices;irradiation procedures;knk-2 reactor;post-irradiation examination
Components Category: --Fuel pins
display the document: 15028668.pdf
In pile operation and post-examination of degassed and wet B4C absorber pins in the KNK II second core, experimental boundary conditions and documentation of the pre-examination results In-Pile Einsatz und Nachuntersuchung entgaster und nasser B4C-Absorberstaebe im KNK II Folgecore, Experimentelle Randbedingungen und Dokumentation der Voruntersuchungsergebnisse
Hoeller, P.;Hoerle, MINTERATOM GmbH, Bergisch Gladbach (Germany)
IA-ITB--54.05968.* - German - 1983
Abstract: In the frame of the KNK II test program twenty (out of the total of fifty-five pins) special pins filled with B4C will be irradiated in the control rod NS-305 on position 312 of the KNK II second core. Out of these twenty pins eight pins are equipped with a diving bell, ten are wet pins with porous plugs and two closed pins have the standard design. In the present report this irradiation experiment is justified and the experimental boundary conditions (irradiation data, specifications and pin distribution) are given. The documentation of the pre-irradiation examinations of the B4C pellets and B4C absorber columns (dimensions, masses, densities) is given in tabulated form. The post-irradiation examinations are planned to be performed in the Hot Cells of the KfK Karlsruhe. The final documentation will be provided by INTERATOM
Key words: boron carbides;control elements;irradiation;knk-2 reactor;neutron absorbers;performance;post-irradiation examination;reactor cores;research programs
Components Category: -Protective and shut-down systems (shutdown rods and drive mechanisms, passive control systems, support systems)
display the document: 34087414.pdf
Evaluation of the ceramographies of the KNK II/1 test zone fuel assembly NY-202-IA Auswertung von Keramographien des KNK II/1 Testzonenbrennelements NY-202-IA
Geier, FINTERATOM GmbH, Bergisch Gladbach (Germany)
IA-ITB--54.06172.9 - German - 1983
Abstract: From the 211 fuel pins of the KNK II/1 fuel assembly NY-202-IA six intact fuel pins were selected in addition to the defective pin for destructive post-irradiation examinations in the Hot Cells of the KfK Karlsruhe. The assembly had been unloaded due to a pin failure after 192 equivalent full-power days and a maximum burnup of 5.4 %. The main aspect of these investigations was to record the fuel and fuel pin behavior and thus to allow a comparison of the status before and after irradiation. The results can also be used for comparative calculations and adaptations of existing calculational models. This report documents in detailed form the results of the fuel and fuel pin examinations
Key words: burnup;ceramography;comparative evaluations;destructive testing;fuel element failure;fuel pins;hot cells;knk-2 reactor;post-irradiation examination
Components Category: --Fuel assemblies
display the document: 34087415.pdf
Evaluation of post-irradiation examination results on oxide fuel pins of the KNK II/1 test subassemblies 208 BN and 202 IA Auswertung von Untersuchungsergebnissen an bestrahlten Oxidbrennstaeben aus den KNK II/1 Testzonen Brennelementen 208 BN und 202 IA
Dienst, W.;Blumhofer, MKernforschungszentrum Karlsruhe GmbH (Germany)
KFK-PSB--01.01.03P82A - German - 1983
Abstract: After a brief survey of the irradiation conditions of the KNK II/1 fuel pins the post-irradiation results are presented and discussed concerning cladding diameter changes, corrosion depth on the cladding inside and the cladding cracks observed. It is demonstrated that after a maximum burnup of 5.1 % cladding plastic strain and cladding inside corrosion do not considerably exceed the data known from previous pin irradiation tests. Combined mechanical and chemical interaction between fuel and cladding is considered to produce the cladding failures observed after 1.2 % and 5.1 % local burnup. In this case the low sintered density of the fuel (nominal 86.5 % of theoretical density) could play a part, but perhaps the cladding material (1.4980) is jointly responsible. The results do not give reason to question in principle the suitability of the fuel pin design applied. But on a long-term basis, it seems advisable to proceed to higher fuel density
Key words: burnup;cladding;corrosion;fuel element failure;fuel pins;fuel-cladding interactions;irradiation;knk-2 reactor;mixed oxide fuels;post-irradiation examination
Components Category: --Fuel assemblies
display the document: 34087762.pdf
Overview of the design of core restraint systems
Heinecke, J. (Internationale Atomreaktorbau G.m.b.H. (INTERATOM), Bergisch Gladbach (Germany, F.R.))IWGFR--54 - English - 1984
Abstract: The optimization of the core restraint system is an important condition for the safe and reliable operation of a fast breeder reactor. For KNK II which is under successful operation and SNR 300 all requirements for safety and operation have been met with help of a ring type system. For SNR 2 the decision between the ring type system and the free standing core has to be done in the near future. Within these considerations the advantages of a ring type restraint system of limiting deflections during operation and limiting of possible movements under seismic conditions have to be balanced against the somewhat more complicated structure of the ring type restraint system
Key words: computerized simulation;knk-2 reactor;reactor core restraints;snr reactor;snr-2 reactor;specifications
Components Category: -Core components
display the document: 18010132.pdf
Post-irradiation examinations on the KNK II/1 fuel element NY-203 with 400 equivalent full-power days residence time and 10 % burnup Nachbestrahlungsuntersuchungen an dem KNK II/1 Brennelement NY-203 mit 400 Vollasttagen Standzeit und 10 % Abbrand
Patzer, G.;Geier, FINTERATOM GmbH, Bergisch-Gladbach (Germany)
IA--54.06442.+ - German - 1984
Abstract: The fuel assembly NY-203 has been irradiated in the first core of KNK II up to a burnup of about 10 % and a residence time of 400 equivalent full-power days. The assembly contained 211 fuel pins with 6.0 mm outer diameter and fuel pellets with the composition (U0.7Pu0.3)O2.00. The cladding material was the austenitic steel 1.4988 lg. Some selected pins were examined in the hot cells of the KfK Karlsruhe. The post-irradiation examinations did not reveal any critical design aspects
Key words: austenitic steels;cladding;design;destructive testing;fuel assemblies;fuel pins;hot cells;knk-2 reactor;mixed oxide fuels;nondestructive analysis;post-irradiation examination
Components Category: --Fuel assemblies
display the document: 34085706.pdf
Intermediate report about the use of fuel assembly test probes, temperature measurement probes and sound recorders in KNK II/1 Zwischenbericht ueber den Einsatz von Brennelementmesssonden, Temperaturmesssonden und Schallaufnehmern in der KNK II/1
Blasius, DINTERATOM GmbH, Bergisch-Gladbach (Germany)
IA-ITB--61.03615.7 - German - 1984
Abstract: During a period of two years fuel element test probes (fetp), temperature measurement probes as well as piezoelectric and magnetostrictive sound recorders (psr and msr) have been tested in KNK II/1 under reactor conditions. The probes had been installed in two experimental plugs, which were inserted into the two rotating plugs of the plant. The two fetp, the two msr and all 10 encased thermocouples have endured the test without damage and did work satisfactorily during the whole test period. Five of the twelve three-wire thermocouples failed, the measuring tip of which was directly exposed to the sodium over a length of about 3 mm. The reason for the failure was the ingress of sodium, which in one case moved up inside the insulation for about five meters. In the two psr the oxygen had leaked from the noble-metal casing, causing a decomposition of the Lithium-Niobate slices and consequently the failure of the sound recorders after about 2000 hours of operation. It was possible to prove, that an adjustment of the fetp is possible in the reactor. However the experimental plugs had an unfavourable hydraulic design, so that a proof of the operational efficiency within the error margins was not possible due to velocity fluctuations
Key words: acoustic monitoring;fuel elements;knk-2 reactor;neutron probes;recording systems;temperature measurement;thermocouples
Components Category: -Monitoring systems, their circuits and electronics
display the document: 34087417.pdf
Operational tests at zero power and at power of the second core of the compact sodium cooled power plant KNK II Funktionspruefungen bei Nulleistung und Leistung des Kerns II/2 der Kompakten Natriumgekuehlten Kernreaktoranlage KNK II
Richard, H.;Schmidt-Hoenow, MKernkraftwerk-Betriebsgesellschaft mbH (Germany), INTERATOM GmbH Bergisch-Gladbach (DE)
KBG--UP0384.2 - German - 1984
Abstract: This report describes the nuclear start-up phase of the second core of KNK II at zero power and up to nominal power. The first criticality was achieved on June 26th, 1983 and full power was reached two months later. The results of reactor physics, thermal-hydraulics and plant engineering measurements were compared with design data. On the plant side a restart of the systems was performed, which had been proven during the first core operation. During the whole start-up phase no disturbing or unforeseen events were observed. The measured parameters (critical mass, control rod worths, reactivity coefficients, temperature rise distributions) agreed well with the results of the pre-calculations within the error intervals
Key words: comparative evaluations;control rod worths;critical mass;experimental data;knk-2 reactor;reactivity coefficients;reactor operation;reactor physics;reactor start-up;temperature distribution;theoretical data;thermal hydraulics
Components Category: -Core components
display the document: 34087736.pdf
Examination of sodium wetted steam generator tube segments of KNK II Nachuntersuchungen natriumseitiger Dampferzeugerrohrabschnitte aus der KNK II
Adelhelm, Ch.;Borgstedt, H.UKernforschungszentrum Karlsruhe GmbH (Germany)
KFK-PSB--01.01.14P07A - German - 1984
Abstract: After 13000 hours operation time the double walled tube No.45 of the KNK II steam generator QS2 has been exchanged and the sodium wetted surfaces and the matrix of the exposed steel 8 CrMoNiNb 9 10 have been examined. Metallographic examinations show, that at 590-770 K the bainitic-ferritic microstructure did not change. By scanning electron microscopy, emission spectroscopy (GDOS) and Auger electron spectroscopy the topography and the composition of the surface have been determined. The surface of the original material is covered by a Zn-containing Cr-enriched oxide layer. After contact with sodium the surface of the outer tube showed an oxide layer, similar to the initial surface. The outer surface of the inner tube is not oxidized, but has the same composition as the original material. Besides a small rising of the carbon level, no selective element leaching has taken place. A corrosion rate has been supposed for the inner wall of 20-30
Key words: auger electron spectroscopy;chromium additions;corrosion;emission spectroscopy;knk reactor;knk-2 reactor;metallography;microstructure;oxides;scanning electron microscopy;spectroscopy;steam generators;steel-crmo;surface properties;thin films;tubes;zirconium
Components Category: -Secondary cooling and steam generator
display the document: 34087770.pdf
Results of post-irradiation examinations of the absorber NS 201 (with pellets) of the KNK II first core Ergebnisse von Nachbestrahlungsuntersuchungen am Absorber NS 201 der Erstbeladung KNK II/1 (mit pelletierten Absorberstaeben)
Hess, BINTERATOM GmbH, Bergisch-Gladbach (Germany)
IA--54.06852.2 - German - 1986
Abstract: The absorber NS-201 of the KNK II first core has been unloaded after a residence time of 273 equivalent full-power days, because gap closure between pellet and cladding had to be expected in 24 pins with B4C-pellets. Selected pins of this element underwent post-irradiation examinations in the hot cells of the KfK Karlsruhe. The evaluated and interpreted results of the investigations, which are documented in this report, allow the conclusion that the absorber could have been irradiated for the full core residence time. The good irradiation behaviour of the pellets and the cladding without any visible interaction, lead to the plan for further irradiation of a complete pellet column of one pin in the third core of KNK II
Key words: absorber pellets;boron carbides;burnup;destructive testing;knk-2 reactor;neutron absorbers;post-irradiation examination;reactor operation
Components Category: -Protective and shut-down systems (shutdown rods and drive mechanisms, passive control systems, support systems)
display the document: 34085710.pdf
Material properties of high density (U,Pu)O2-fuel for use in fuel behavior models Materialeigenschaften von hoch-dichtem (U,Pu)O2 Brennstoff fuer Modelle zum Brennstoffverhalten
Toebbe, H.;Freund, D.;Gaertner, HINTERATOM GmbH, Bergisch Gladbach (Germany), Kernforschungszentrum Karlsruhe GmbH (DE)
IA--54.06862.6 - German - 1986
Abstract: This report presents a collection of materials properties data for use in fuel performance and safety calculations and specifically for the IAMBUS and SATURN fuel behavior models. Data are given for the physical fuel properties, for the fuel behavior under irradiation and for the fuel-gap conductance. This set of material correlations was established in a common working group of KfK/INTERATOM with special respect to high density (U,Pu)O2-fuel
Key words: creep;irradiation;knk-2 reactor;mechanical properties;mixed oxide fuels;performance;swelling
Components Category: --Fuel assemblies
display the document: 34085711.pdf
Summary of the post-irradiation examinations of the defective fuel assembly NY-202 of the KNK II first core Zusammenfassende Darstellung der Nachbestrahlungs-Untersuchungen am defekten Brennelement NY-202 der Erstbeladung KNK II/1
Hess, BINTERATOM GmbH, Bergisch-Gladbach (Germany)
IA--54.06874.3 - German - 1986
Abstract: The defective fuel assembly NY-202 of the test zone of the KNK II first core had been irradiated for further 12 days with reduced reactor power after detection of a fuel pin failure and its localization. After unloading and cooling in the sodium storage the assembly had been transported to the hot cells of the KfK Karlsruhe for post-irradiation examinations. This report summarizes the results of these examinations as well as the interpretations with respect to the general fuel and fuel pin behavior and the analysis' of causes and mechanisms of the cladding failure. The results show a normal irradiation behavior of the fuel and the fuel pins, which is conform with the expectations, with the exception of local surface abrasion of fuel pins and spacers, which is due to mechanical interactions as a special phenomenon of the first KNK II loading. The results allow the derivation of more or less clear differences in the behavior of the two fabrication campaigns differing by 1.5 years. The cladding failure can be explained with high probability by strong inner corrosion of the cladding with local corrosion due to chemical interaction with fuel impurities
Key words: cladding;corrosion;destructive testing;failures;fuel element failure;fuel pins;hot cells;knk-2 reactor;nondestructive analysis;post-irradiation examination;spacers
Components Category: --Fuel assemblies
display the document: 34085713.pdf
Material correlations and models for the irradiation behavior of fissile and fertile material in SNR-300, Mark-II and KNK II, third core Materialkorrelationen und Modelle zum Brennstoff- und Brutstoffbestrahlungsverhalten fuer SNR-300, Nachladung Mark-II und 3. Kern KNK II
Fenneker;Steinmetz;ToebbeINTERATOM GmbH, Bergisch-Gladbach (Germany)
IA--54.06938.3 - German - 1986
Abstract: The report contains the material correlations and models used in the fuel pin design code IAMBUS for the irradiation behavior of PuO2-UO2 fissile materials and UO2 fertile materials of the SNR-300 Mark-II reload and the KNK II third core. They are applicable for pellet densities of more than 90 % of the theoretical density. The presented models of the fuel behavior and the applied material correlations have been derived either from single experiments or from the comparison of theoretically predicted integral fuel behavior with the results of fuel pin irradiation experiments. The material correlations have been examined and extended in the frame of the collaborations INTERATOM/KWU and INTERATOM/KfK. French and British results were included, when available from the European fast reactor knowledge exchange
Key words: fuel pins;i codes;irradiation;knk-2 reactor;mechanical properties;mixed oxide fuels;performance testing;reactor fueling;uranium dioxide
Components Category: --Fuel assemblies
display the document: 34085714.pdf
Behavior of the core coolant outlet temperatures of KNK II. Performed investigations, summary of the results and present status of knowledge Verhalten der Kuehlmittelaustrittstemperaturen beim Kern KNK II/2. Durchgefuehrte Untersuchungen, Zusammenfassung der Ergebnisse und gegenwaertiger Kenntnisstand
Finke, GKernkraftwerk-Betriebsgesellschaft mbH (Germany)
KBG--BL1/86 - German - 1986
Abstract: The coolant outlet temperatures of the Mark II test zone fuel assemblies of the second core of KNK II started to rise slowly about 20 equivalent full-power days (efpd) after their start-up. After about 100 efpd the increase came to saturation, having reached values of 20 to 30 K. From May to August 1984 the plant was shutdown for the replacement of different experimental facilities, and after restart the temperature rises were about halved, but reached their original level during the following operation. Also a fresh assembly, which had to replace a defective one after 280 efpd, showed the same phenomenon, i.e. similar increase with similar speed. During a shutdown phase from October 1985 until March 1986 different experiments were performed at the plant, and in parallel to that out-of-pile experiments and theoretical investigations were performed to clarify the phenomenon. The explanation of the temperature drifts has to be seen in impurities in the sodium, which deposit on the surface of the fuel claddings and the pin spacers, thus leading to an increased surface roughness and thermohydraulic resistance in the fuel assemblies. Additionally, larger particles or agglomerates of smaller ones could deposit on the grid spacers causing a partial blockage of the free flow area. Since the deposits do not stick firmly to the surface, they are partly removed by the flowing sodium, so that the saturation effect of the temperature increase could be explained. These explanations are being supported by experiences gathered in foreign plants
Key words: cladding;deposits;friction;fuel assemblies;knk-2 reactor;reactor fueling;reactor operation;roughness;spacers;temperature distribution;temperature measurement;thermal hydraulics
Components Category: --Fuel and cladding
display the document: 34087731.pdf
Irradiation examinations on the KNK II/1 control rod NS-204 Bestrahlungsuntersuchungen am KNK II/1 Absorber NS-204
Geier, FINTERATOM GmbH, Bergisch Gladbach (Germany)
IA--54.07114.5 - German - 1987
Abstract: The control rod NS-204 has been operating during the whole operating period of the KNK II first core of 400 equivalent full-power days. The assembly contained 55 pins with 93 % enriched granulated B4C. The goal of the post-irradiation examination in the Hot Cells of the KfK Karlsruhe was to get information about the pin performance under irradiation in the fast neutron flux. Main parameters of interest were the helium release rate, the swelling and sintering process of the granulated B4C and the compatibility of the B4C and the cladding material. The report describes the results of the destructive and non-destructive analysis in the Hot Cells. All absorber pins were found to be intact, and maximum B10-burnups of 6.6x10''2''1 captures per cm3 were reached. The helium release rate amounted to maximum 2.5 %
Key words: absorber pellets;boron 10;boron carbides;burnup;cladding;control elements;destructive testing;fuel assemblies;hot cells;knk-2 reactor;nondestructive analysis;performance testing;post-irradiation examination;reactor control systems
Components Category: -Protective and shut-down systems (shutdown rods and drive mechanisms, passive control systems, support systems)
display the document: 34085721.pdf
Post examinations of fuel pins of the KNK II fuel element NY-308 with Niobium coating Nachuntersuchungen von Niob-innenbeschichteten Brennstaeben aus dem KNK II/2 Brennelement NY-308
Patzer, G.;Hess, BINTERATOM GmbH, Bergisch-Gladbach (Germany)
IA--54.07318.7 - German - 1987
Abstract: In the fuel assembly NY-308 of the second core of KNK II two fuel pins with a Niobium coating on the inner cladding surface underwent post-irradiation examinations, one of them a destructive one. The examinations demonstrated a getter-effect of the Nb-layer, which did influence the axial Cesium distribution, especially in the upper part of the fuel column. Additionally, the inner cladding corrosion was prevented successfully. On the Nb-layer itself mechanical attacks and changes, like peel-off or chip-off effects, were found. These did however not influence the effectiveness of the Nb-layer obviously. Investigations on other fuel pins with Nb-coated claddings and much higher fuel burnup, which are still being irradiated, are promising further knowledge
Key words: cladding;corrosion;fuel assemblies;fuel pins;knk-2 reactor;niobium;performance testing;post-irradiation examination;surface coating
Components Category: --Fuel and cladding
display the document: 34085723.pdf
KNK II: Measures to avoid abrasion damages in the test- and driver-subassemblies of the third core KNK II: Massnahmen zur Vermeidung von Verschleissschaeden in den Test- und Treiberelementen des dritten Kerns
Toebbe, H.;Wenk, K.HINTERATOM GmbH, Bergisch-Gladbach (Germany)
IA--54.07305.8 - German - 1987
Abstract: The fuel assemblies of the third core of KNK II have to be improved due to the experience and the post-irradiation examinations about the fuel element performance in the second core in order to avoid the fuel failure causing abrasion phenomenon. For this purpose modifications at the structural components are proposed and discussed, which are partly alternatively and partly additively suitable to avoid that type of failures of the second core
Key words: abrasion;deposits;fuel element failure;knk-2 reactor;post-irradiation examination;reactor operation
Components Category: --Fuel assemblies
display the document: 34085722.pdf
Summarizing presentation of non-destructive post-irradiation examinations of the fuel subassembly NY-308 of the KNK II/2 second core Zusammenfassende Darstellung zerstoerungsfreier Nachbestrahlungsuntersuchungen am Brennelement NY-308 der Zweitbeladung KNK II/2
Hess, BINTERATOM GmbH, Bergisch-Gladbach (Germany)
IA--54.07324.3 - German - 1987
Abstract: The fuel subassembly NY-308 of the KNK II/2 Test-zone has been irradiated for further 23 equivalent full-power days (efpd) after a fuel pin failure had been detected after 250 efpd. After the necessary reduction of the decay heat, non-destructive post irradiation examinations were performed on that subassembly in the hot cells of the KfK, Karlsruhe. Their results are presented in this report. Main unexpected results were the wear-marks on fuel pin surfaces as a consequence of mechanical interaction between fuel pins and pin spacers and between neighbouring fuel pins. The location and appearance of the cladding failure indicated a causative connection of the local cladding weakening and the defect itself. Despite the continuing operation with the defect fuel pin neither an evident fuel discharge nor a failure propagation occurred. This result is a complete confirmation of the experience with the continuing operation of the defect fuel pin of the first core of KNK II
Key words: fuel element failure;fuel pins;knk-2 reactor;nondestructive testing;post-irradiation examination;reactor cores;reactor operation;spacers;wear
Components Category: --Fuel assemblies
display the document: 34085724.pdf
Summarizing presentation of non-destructive post-irradiation examinations of the moderated driver subassembly NW-302 of the KNK II/2 second core Zusammenfassende Darstellung zerstoerungsfreier Nachbestrahlungsuntersuchungen am moderierten Treiberelement NW-302 der Zweitbeladung KNK II/2
Hess, BINTERATOM GmbH, Bergisch-Gladbach (Germany)
IA--54.07365.* - German - 1987
Abstract: The fuel subassembly NW-302 of the KNK II/2 driver zone has been irradiated for further 48 equivalent full-power days (efpd) after a fuel pin failure had been detected after 310 efpd. After the necessary reduction of the decay heat, non-destructive post irradiation examinations were performed on that subassembly in the hot cells of the KfK, Karlsruhe. Their results are presented in this report. Similarly to the fuel pins of the test zone element NY-308 wear-marks with similar axial intensity distribution were observed on the fuel pin surfaces as a consequence of mechanical interaction between fuel pins and pin spacers. The interaction between neighbouring pins was observed only between fuel pins and not between fuel and moderator pins. Additionally, locally limited rugged deposits were observed on the fuel pins, with smaller extent on the moderator pins. As a consequence of the cladding weakening, two cladding failures occurred during the reactor operation independently from each other. Neither an evident fuel discharge nor a failure propagation occurred, which is a confirmation of the former experience with the continuing operation of defect fuel pins
Key words: fuel element failure;fuel pins;hot cells;knk-2 reactor;nondestructive testing;post-irradiation examination;reactor operation;zirconium hydrides
Components Category: --Fuel assemblies
display the document: 34085725.pdf
International experience with the bundle behavior of fuel elements of sodium cooled reactors. Derivation of a figure of merit for the judgement of fuel pin bundle parameters with respect to abrasion due to thermoelastic pin-pin interaction Internationaler Erfahrungsstand zum Buendelverhalten von SNR-Brennelementen. Richtgroesse zur vergleichenden Beurteilung der Buendelparameter bezueglich Verschleiss infolge thermoelastischer Stab/Stab-Wechselwirkung
Toebbe, HINTERATOM GmbH, Bergisch-Gladbach (Germany)
IA--54.07375.3 - German - 1987
Abstract: The report describes the status of experience with respect to the abrasion behavior of bundles in standard fuel elements and test elements with wire or grid spacing in the reactors Rapsodie fortissimo, Phenix, DFR, PFR, EBR-II, FFTF, JOYO and KNK II. With the help of simple considerations concerning thermoelastic pin-pin interactions a figure of merit is deduced from the different bundle parameters, which allows a comparative judgement of the parameters of different bundle concepts
Key words: abrasion;dfr reactor;ebr-2 reactor;fuel assemblies;fuel pins;international cooperation;joyo reactor;knk-2 reactor;performance;pfr reactor;phenix reactor;rapsodie reactor;spacers;thermoelasticity
Components Category: --Fuel pins
display the document: 34085726.pdf
Metallographic examinations of the wear-marks on fuel pins of the KNK II/2 fuel assembly NY-308 Metallographische Untersuchung der Reibmarken an Brennstaeben aus dem KNK II/2 Brennelement NY-308
Patzer, GINTERATOM GmbH, Bergisch Gladbach (Germany)
IA--54.07415.9 - German - 1987
Abstract: On the fuel pins and pin spacers of the fuel assembly NY-308 of the second core of KNK II pronounced wear marks had been found in the area of the contact points. In order to determine the exact form of the marks, metallographic investigations were performed on two test pieces of fuel pins in the Hot Cells of the KfK Karlsruhe. It was found that the wear marks did show the already observed stratified structure. Next to the unchanged cladding area there is a peripheral zone with modified grain structure, followed by a layer of moved material and finally there is a flake-like zone of accumulated cladding material at the lower end of the wear marks. Longitudinal cuts do not show grain deformations, which could indicate axial friction forces between pin and spacer. The wear marks are rapidly dropping to their maximum depth at the ends and the depth shows a relatively uniform pattern between both. The findings are confirming the picture, that a stirring movement of the fuel pins took place, which caused adhesive wear
Key words: abrasion;cladding;destructive testing;friction;fuel pins;hot cells;knk-2 reactor;metallography;post-irradiation examination;spacers;wear
Components Category: --Fuel assemblies
display the document: 34085727.pdf
Influence of deposits on fuel pins and pin spacers of the fuel subassemblies on the temperature increase distribution of the fuel subassemblies in KNK II/2 Einfluss von Ablagerungen auf den Brennstaeben und Abstandshaltern der Brennelemente auf die Aufwaermspannenverteilung der Brennelemente der KNK II/2
Heinecke, JINTERATOM GmbH, Bergisch-Gladbach (Germany)
IA--54.07431.9 - German - 1987
Abstract: Post-irradiation examinations of two fuel subassemblies of KNK II/2 have shown deposits of impurities of the sodium on the fuel pins and the pin spacers. It is shown in the report, that these deposits can be the origin of the differences between the measured and the pre-calculated temperature increases of the fuel subassemblies
Key words: deposits;fuel assemblies;knk-2 reactor;post-irradiation examination;sodium;spacers;temperature distribution;thermal hydraulics
Components Category: --Fuel pins
display the document: 34085728.pdf
Influence of fabrication parameters on the operational behavior of fuel pins Einfluss von Herstellungs-Parametern auf das Betriebsverhalten von Brennstaeben
Ritzhaupt-Kleissl, H.-J.;Elbel, H.;Heck, MKernforschungszentrum Karlsruhe GmbH (Germany)
KFK-PSB--01.01.02P17F - German - 1987
Abstract: During the last recent years investigations on structure and properties of high dense FBR fuel types were performed. One of the most important parameters is the thermal conductivity. As could be observed, microcracks in the material can influence the thermal conductivity by up to about 20 %. The occurrence of these microcracks is related to local stoichiometry changes in the fuel. By pre-test modelling calculations the influence of the following fuel fabrication parameters on the fuel pin behavior was studied: fuel stoichiometry, pellet diameter, purity of the backfill gas and sintering atmosphere. These calculations show, that a reduction of fuel stoichiometry from O/M=1.97 to 1.93 results in a centerline temperature increase of about 8 %. The influence of a change in backfill gas composition from 90 % He to 50 % He is less pronounced. A larger pellet diameter leads, generally, to higher centerline temperatures during operation
Key words: cracks;fabrication;fuel elements;irradiation;knk-2 reactor;mechanical properties;microstructure;performance;sintering;stoichiometry;thermal conductivity
Components Category: --Fuel pins
display the document: 34087753.pdf
Nondestructive post-irradiation examinations on fuel pins of the fuel assembly NY-305 of the second core of KNK II (status of 15.01.1988) Zerstoerungsfreie Nachbestrahlungsuntersuchungen an Brennstaeben des Brennelementes NY-305 des 2. Kerns der KNK II (Stand vom 15.01.1988)
Hess, BINTERATOM GmbH, Bergisch Gladbach (Germany)
IA--54.07478.6 - German - 1988
Abstract: After detection of a fuel pin defect at 400 equivalent full-power days (efpd), the fuel assembly NY-305 of the KNK II/2 test zone had been operated for further four efpd. After reduction of the decay heat, the assembly was brought to the Hot Cells of the KfK Karlsruhe for nondestructive post-irradiation examinations. A maximum burnup of 6.3 % had been reached. As an overview, this report summarizes the performed work of the nondestructive examinations and gives a first valuation. The mechanical interaction between spacers and fuel pins shows the already known consequences: Local cladding wear in the upper spacer planes and lengtheninged pin-to-pin contacts between the 5th and 7th spacer. The axial intensity distribution of the cladding wear in the height of the spacer and the radial tendency of this wear are corresponding to the prevailing results and can be considered to be typical for this type of interaction
Key words: cladding;failed element detection;fuel assemblies;fuel pins;knk-2 reactor;nondestructive analysis;post-irradiation examination;spacers;wear
Components Category: --Fuel assemblies
display the document: 34087379.pdf
Fuel and fuel pin behaviour in a high burnup fast breeder fuel subassembly: Results of destructive post-irradiation examinations of the KNK II/1 fuel subassembly NY-205 Brennstoff- und Brennstabverhalten in einem Hochabbrand Schnellbrueter-Brennelement: Ergebnisse aus der zerstoerenden Nachuntersuchung des KNK II/1 Brennelementes NY-205
Patzer, GINTERATOM GmbH, Bergisch-Gladbach (Germany)
IA--54.08066.4 - German - 1991
Abstract: The report gives a summarizing overview of the design characteristics, of the irradiation history and of the results of the destructive post-irradiation examinations of the fuel pins of the high-burnup fuel subassembly NY-205 of the KNK II first core. This element was operated for about 10 years and reached a maximum local burnup of 175 MWd/kg(HM) and a maximum neutron dose of 67 dpa-NRT. The main design data of this subassembly agree with those of the SNR 300 Mark-Ia, and it reached more than twice of the burnup and a similar neutron dose as foreseen for the SNR 300 fuel subassemblies
Key words: atomic displacements;burnup extension;burnup;destructive testing;knk-2 reactor;post-irradiation examination;reactor operation
Components Category: --Fuel assemblies
display the document: 34087386.pdf
Irradiation experience with KNK II Fast Breeder Fuel Subassemblies Bestrahlungserfahrungen mit KNK II-Schnellbrueter-Brennelementen
Hess, BSiemens AG, Bereich Energieerzeugung, KWU (Germany)
KWU-BGL-N--22-1993-E001 - German - 1993
Abstract: During the operation of the second core of KNK II fuel pin failures occurred, which were caused by local cladding weakening due to mechanical interaction between fuel pins and pin spacers. The present report gives a summarizing presentation of the consequences of these interactions, of the experimental and theoretical investigations to clarify the reason for the interactions and of measures to reduce their consequences in the extended residence time of the second core of KNK II. This type of interaction is caused by thermo-elastic instabilities of the fuel pin bundle, and its strength depends sensitively on the geometry of the pin bundle and the pin power. Finally, measures are described, which were taken for the fuel subassemblies of the third core of KNK II to avoid the wear causing instabilities
Key words: burnup;fuel element failure;instability;knk-2 reactor;performance;reactor operation
Components Category: --Fuel assemblies
display the document: 34086311.pdf
Post-irradiation examinations and theoretical analyses of the fuel and fuel pin behavior of innovative systems. Bestrahlungsnachuntersuchungen und modelltheoretische Analysen zum Brennstoff- und Brennstabverhalten innovativer Systeme
Ernst, W.;Freund, D.;Geithoff, D.;Heck, M.;Jacobi, O.;Steiner, H.;Weimar, PFZKA--5600 - German - 1995
Abstract: For the development of LMR cladding materials an irradiation test was performed in the KNK II reactor between 1986 and 1991. It demonstrated that a temperature gradient in the cladding has no observable effect on swelling behavior. PIEs of transient experiments in the Petten HFR have shown no significant cladding deformations. (orig.)
Key words: fuel cans;knk-2 reactor;post-irradiation examination;reactor safety experiments;transients
Components Category: --Fuel and cladding
display the document: 28005773.pdf