TY - JOUR A1 - Erhard, Anton A1 - Schuler, X. A1 - Otremba, Frank T1 - A new concept for steam generator tube integrity assessment N2 - Steam generator (SG) tubes are part of the primary circuit of pressurised water reactors and therefore also part of the pressure retaining boundary components. Furthermore, steam generator tubes are the components which guarantee the separation between the primary and secondary circuits. Therefore the knowledge of the loss of tube integrity as soon as possible is an essential. Optimised nondestructive testing methods based on the eddy current array technique are used to find material degradation, especially intergranular stress corrosion cracks during the periodical in-service inspection. These methods are supported by the measurement of the leakage rate during operation based on radioactivity and Tritium measurement regarding a high crack grows. Shutdown criteria depending on leakage rates which are described in the operation procedures but there are no specifications about the conditions for the measured leakage. Is the leakage coming from a single crack or are there multiple cracks or is this the leakage of a critical crack. With the help of FE calculations answer about the uncertainties of leakage rate versus critical crack grows were found. Shutdown criteria must guarantee to avoid critical crack sizes, i.e. between the measured tritium activity and the critical crack size must be a safety gap. KW - Steam generator tubes KW - Crack detection KW - Non destructive testing KW - Axial cracks KW - Critical crack sizes KW - Crack opening area KW - Leakage PY - 2012 U6 - https://doi.org/10.1016/j.nucengdes.2012.04.014 SN - 0029-5493 SN - 1872-759X VL - 249 SP - 297 EP - 303 PB - North-Holland Publ. Co. CY - Amsterdam AN - OPUS4-26025 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Erhard, Anton A1 - Kutzner, Jürgen A1 - Wüstenberg, Hermann A1 - Mundry, Eberhard T1 - Abhängigkeit der Echoanzeige von nutartigen Reflektoren vom Prüfkopfschallfeld und von der Frequenz PY - 1979 SN - 0340-7551 VL - 9 IS - 1 SP - 11 EP - 12 PB - Bundesanstalt für Materialprüfung CY - Berlin AN - OPUS4-9176 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Erhard, Anton A1 - Kutzner, Jürgen A1 - Wüstenberg, Hermann A1 - Mundry, Eberhard T1 - Abhängigkeit der Echoanzeige von nutartigen Reflektoren vom Prüfkopfschallfeld und von der Frequenz PY - 1977 SN - 0025-5300 VL - 19 IS - 9 SP - 379 EP - 382 PB - Carl Hanser Verlag CY - München AN - OPUS4-8759 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Erhard, Anton A1 - Völzke, Holger A1 - Probst, Ulrich A1 - Wolff, Dietmar T1 - Aging management for long-term interim storage casks N2 - The aging management system for the mechanical components of nuclear power plants (NPPs) must be established and used by the licensee in such a way that the quality of safety relevant components is guaranteed for the completely designed lifetime of the NPP. This demands an extensive plant life management with special emphases on the knowledge of the degradation in material properties. The basic safety concept in Germany observes this circumstance. Lifetime extension of the German NPPs is an aim of the current valid coalition agreement of the German government. Operational extension of interim storage facilities requires, in comparison to the aging management system for NPP, an aging management system adapted to the Special circumstances of spent fuel storage casks. Extension of interim storage periods for spent fuel casks beyond the designed lifetime requires, in comparison to the components of an NPP, an increasing knowledge of material degradation with potential impact on cask integrity, e.g. leak tightness. Dry interim storage in Germany has been approved for 40 years. After that time, according to the present strategy, a final repository should be available. However, until now, such a final facility still does not exist, and the German exploration and licensing process is heavily delayed. Currently, discussions are continuing regarding further exploration of the Gorleben salt mine. There is willingness to overcome this situation that is clearly described in the available coalition agreement of the federal government. Anyway, however, the prediction is viewed; a repository for heat generating radioactive waste in Germany will not be available in the near future and may not be available when first storage facilities and casks reach their 40 years of approved lifetime, which will occur in ~25 years starting from now. Therefore, the question must be asked: what has to be done with the existing storage casks in the interim facilities? May these casks be fit for continued use, with an extension of the storage period? One option is to have an aging management system, which creates enough information about the technical condition of safety relevant cask properties. This is the basis for safety evaluation for extended storage periods. In the present paper, possible aging mechanisms for high level waste storage casks are discussed, as well as the influence of the time dependent changes of the component properties. KW - Long term interim storage KW - Storage casks KW - Aging mechanisms KW - Degradation mechanisms KW - Metal seals KW - Larson-Miller parameter PY - 2011 U6 - https://doi.org/10.1179/1746510910Y.0000000013 SN - 1746-5095 SN - 1746-5109 SN - 0957-476X VL - 22 IS - 1 SP - 46 EP - 53 PB - Ramtrans Publ. CY - Ashford AN - OPUS4-23890 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bovtun, Viktor Petrovic A1 - Döring, Joachim A1 - Wegener, M. A1 - Bartusch, Jürgen A1 - Beck, Uwe A1 - Erhard, Anton A1 - Borisov, V. T1 - Air-coupled ultrasonic applications of ferroelectrets KW - Air-coupled ultrasonics KW - Non-contact transducers KW - Ferroelectrets KW - Electromechanical properties PY - 2008 U6 - https://doi.org/10.1080/00150190802380243 SN - 0015-0193 SN - 1563-5112 VL - 370 IS - 1 SP - 11 EP - 17 PB - Taylor & Francis CY - New York, NY AN - OPUS4-20924 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Bovtun, V. A1 - Döring, Joachim A1 - Bartusch, Jürgen A1 - Beck, Uwe A1 - Erhard, Anton A1 - Yakymenko, Y. T1 - Air-coupled ultrasonic transducers based on cellular polypropylene ferroelectret films N2 - Analysis of the dielectric and electromechanical properties of the cellular polypropylene ferroelectret films (EMFIT) evidences their high potential for the application in the air-coupled ultrasonic transducers. Simple prototype transducers, based on the EMFIT films, were developed and their high sensitivity was proved in the air-coupled ultrasonic experiment. Amplitude and delay time scanned images of the polyethylene step wedge with holes, obtained in both pulse-echo and transmission modes, demonstrate that non-contact ultrasonic imaging with EMFIT transducers is possible. KW - Air-coupled ultrasonics KW - Non-contact transducers KW - Ferroelectrets KW - Electromechanical properties PY - 2007 SN - 0015-0193 SN - 1563-5112 VL - 353 IS - 1 SP - 186 EP - 192 PB - Taylor & Francis CY - New York, NY AN - OPUS4-14977 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Erhard, Anton A1 - Otremba, Frank A1 - Mohr, F. A1 - Kilian, R. T1 - Alloy 800 steam generator tube stress corrosion cracks - detection and root cause KW - Tube inspection PY - 2012 SN - 0007-1137 VL - 54 IS - 6 SP - 1 EP - 5 PB - British Institute of Non-Destructive Testing CY - Northampton AN - OPUS4-26006 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wüstenberg, Hermann A1 - Erhard, Anton A1 - Schenk, Gottfried A1 - Montag, Hans-Joachim T1 - Anwendung der Ultraschalltomographie an Turbinen und Generatorwellen T2 - 12. MPA-Seminar CY - Stuttgart, Deutschland DA - 1986-10-16 PY - 1987 SN - 0025-5300 VL - 29 IS - 10 SP - 297 EP - 302 PB - Carl Hanser Verlag CY - München AN - OPUS4-18764 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Erhard, Anton A1 - Wüstenberg, Hermann A1 - Schulz, Eduard A1 - Mundry, Eberhard T1 - Anwendungen der longitudinalen Kriechwelle in der zerstörungsfreien Prüfung mit Ultraschall und Erfahrungen beim Einsatz von Kriechwellenprüfköpfen PY - 1982 SN - 0025-5300 VL - 24 IS - 2 SP - 43 EP - 48 PB - Carl Hanser Verlag CY - München AN - OPUS4-18748 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wüstenberg, Hermann A1 - Erhard, Anton A1 - Schulz, Eduard A1 - Schenk, Gottfried T1 - Auffindung von oberflächennahen Rissen in Schweißverbindungen mittels der Ultraschallprüfung PY - 1985 SN - 0253-5262 VL - 39 IS - 7 SP - 110 EP - 115 CY - Wien AN - OPUS4-18757 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -