Nakano, Masanao; Fujii, Tomoko; Nemoto, Masashi; Tobita, Keiji; Kono, Takahiko; Hosomi, Kenji; Nishimura, Shusaku; Matsubara, Natsumi; Maehara, Yushi; Narita, Ryosuke; et al.
JAEA-Review 2019-048, 165 Pages, 2020/03
Environmental radiation monitoring around the Tokai Reprocessing Plant has been performed by the Nuclear Fuel Cycle Engineering Laboratories, based on "Safety Regulations for the Reprocessing Plant of Japan Atomic Energy Agency, Chapter IV - Environmental Monitoring". This annual report presents the results of the environmental monitoring and the dose estimation to the hypothetical inhabitant due to the radioactivity discharged from the plant to the atmosphere and the sea during April 2018 to March 2019. In this report, some data include the influence of the accidental release from the Fukushima Daiichi Nuclear Power Station of Tokyo Electric Power Co., Inc. (the trade name was changed to Tokyo Electric Power Company Holdings, Inc. on April 1, 2016) in March 2011. Appendices present comprehensive information, such as monitoring programs, monitoring methods, monitoring results and their trends, meteorological data and discharged radioactive wastes. In addition, the data which were influenced by the accidental release and exceeded the normal range of fluctuation in the monitoring, were evaluated.
Morihira, Masayuki; Ozawa, Takayuki; ; Suzuki, Masahiro; Shigetome, Yoshiaki; Kihara, Yoshiyuki; Kono, Shusaku
JNC TN8400 2004-014, 193 Pages, 2004/07
The collaboration project concerning sphere-pac fuel among JNC, Swiss PSI (Paul Scherrer Institut) and Dutch NRG (Nuclear Research and Consultancy Group) is in progress.Final target of the project is comparative irradiation tests of Sphere-pac fuel in the HFR (High Flux Reactor) in Petten in the Netherlands with pellet type fuel and vipack fuel. Total 16 fuel segments (8 pins) of these three types of fuel are planned to be irradiated. Two sphere-pac fuel segments contain 5%Np in addition to 20%Pu-MOX. Other segments contain no Np. Fabrication of irradiation test pins was completed till May 2003 in PSI. After transportation of the fuel pins to Petten, two times of irradiation were performed in January to March in 2004 and now post irradiation tests are in progress. Later two irradiations will be done till the autumn in 2004.This report summarized the basic plan, fuel design, and fabrication of irradiation test pins concerning this collaboration project.
; Kono, Shusaku
Nihon Genshiryoku Gakkai Wabun Rombunshi, 3(1), p.95 - 105, 2004/03
Seki, Masayuki; Kono, Shusaku; Kihara, Yoshiyuki; Kaito, Takeji; Ukai, Shigeharu; Hirako, Kazuhiko*
Journal of Nuclear Materials, 329-333, p.1534 - 1538, 2004/00
Welding technology for fuel cladding and end-plugs made of ODS steel has been developed to apply for the fast reactor fuel pin fabrication at Tokai-works of JNC. A pressurized resistance welding (PRW) method is utilized as solid phase welding. The method is based on electrical resistance heating of the components while maintaining a continuous force sufficient to forge weld without melting of the components. The contact force between cladding and end-plug is given by pneumatic-hydraulic system. The welding parameters, e.g. electric current, voltage and contact force, are controlled by a programmable system. The appropriate conditions are selected to be a 700 Kgf contact load with 16 kA current for 20 ms after holding for pre-heating by 6 kA current. For relieving the residual stress, the post-welded heat-treatment is performed in the condition of tempering at 1053 K for 10 min. A metallugically bonded welds has been formed by the PRW method, keeping the original dispersed distributio
Kono, Shusaku; Seki, Masayuki; Fujio, Ishibashi,; Hirako, Kazuhiko*; Tsukada, Tatsuya*
JNC TN8430 2003-010, 28 Pages, 2003/07
The defect occurred at the resistance welding zone is very minute and therefore cannot be identified by X-ray inspection. Then, the ultrasonic examination method, in which the resolution of the defect is higher than that of the X-ray inspection method, has been developed. The ultrasonic wave sounds straight easier in the material than X rays, excels in defecting the micro defect. However, the pulse amplitude of ultrasonic wave is influenced by the shape and direction of the defect. Then, the ultrasonic inspection equipement, in which the ultrasonic probe and the sample rotation axis are controlled to drive with the pulse motor and the defect data (position and size)are analized by image processing ultrasonic signal, was developed to measure the shape and the position of defect accurately. However, an ultrasonic examination method is the comparative inspection method. Therefore, the standard test block or the reference block is indispensable to guarantee the defectability and the ultrasonic echo sensibility of the inspection device. The standard test block is provided in JIS etc, it is needed to defect the peculiar defect occurred at the resistance welding zone. Then, the method of processing a standard test block is examined, the standard test block was made experimentally by electric discharge processing and diffusion junction method. The ultrasonic echo sensitivity and the threshold for image processing were proofread by using the standard test block, the ultrasonic inspection and metallographic inspection were executed. Comparing the ultrasonic inspection results with the metallographic inspection results, the detectability of defect depth and the measurement accuracy were proved to be 3m and with errors less than 10m respectively. From these results, the effectireness of proofreading the ultrasonic inspection condition by the standard test block was confirmed. Moreover, it was confirmed that there was a peculiar relationship between the depth ...
Yamawaki, Michio*; Konashi, Kenji*; Kono, Shusaku; Kitamura, Ryoich
JNC TY8400 2003-006, 38 Pages, 2003/05
The actinide-hydride fuel is an excellent integral fuel - moderator system. The concentration of hydrogen in the actinide hydride is comparable to that of hydrogen in liquid water of LWR cores. We have proposed new type of reactor core to reduce the amoun
Kono, Shusaku; Seki, Masayuki; Ishibashi, Fujio; Hirako, Kazuhiko*; Tsukada, Tatsuya*
JNC TN8410 2003-009, 108 Pages, 2003/05
The welding condition and the heat-treatment condition were optimized to evaluate welding properties of the martensitic ODS steel cladding tube. The test pieces for evaluation of strength properties of the welded zone were produced by the optimized welding condition. In order to evaluate the strength of the welded zone, the internal creep rapture test, the single axis creep rapture test, the burst test and the tensile test were conducted. Following results were obtained in these tests. (1) Weld ability. An excellent welding characteristic was observed. The micro cracks, etc. were not served at the joint starting point. The joint starting poonts were connected uniformly with errors less than 0.05mm. It is considered that an excellent welding characteristic was result of homogeneous micro structure of cladding material. (2) End plug material. In case of the material of end plug was martensitic ODS steel as same as that of cladding tube, the micro structure and the precipitation state carbide near the welded zone were found to be almost same as that of cladding tube. (3) Optimization of heat-treatment condition. The heat treatments of normalizing (10501C) and tempering (780C) were performed after welding and the micro structure near the welded zone was the isometric structure with low dislocation density, the precipitation state of carbide was uniform as same as that of cladding tube. These heat treatments can relax the residual stress accumulated when welding; it is considered that these heat treatments after welding are indispensable. (4) Strength of welded zone. The strength of the welded zone was found to be equal to that of cladding tube in all the strength tests. Therefore, it is concluded that the welding technology for the martensitic ODS steel is completed.
; ; Shigetome, Yoshiaki; Kono, Shusaku;
JNC TN8410 2003-002, 29 Pages, 2003/02
Japan Nuclear Cycle Development institute (JNC) has conducted the collaboration concerning vibro-packed fuels with Paul Scherrer Institut (PSI) in Switzerland and Nuclear Research & consultancy Group (NRG) in the Netherlands. The project "Research and Development of Advanced Sphere-pac fuel" is called FUJI (FUel irradiations for JNC and PSI) Project. In this project, three types of fuels that are sphere-pac fuels, vipac fuels, and pelletized fuels will be irradiated in the High Flux Reactor (HFR) to compare the fuel performance. Based on the drawing which has been agreed among three parties, fabrication of the pin components and welding of the upper and lower connection endplugs were performed in accordance with ISO-9001 in JNC. This report describes data of fabricated pin components, results of welding qualification tests, and quality assurance of the welded components. The fabrication of pin components was successfully completed and they were delivered to PSI in October 2002.
Morimoto, Kyoichi; Kato, Masato; Nishiyama, Motokuni; Endo, Hideo; Kono, Shusaku; Uno, Hiroki*; Tamura, Tetsuya*; Sugata, Hiromasa*
JNC TN8400 2003-011, 32 Pages, 2003/01
MOX fuel containing Neptunium is being developed as candidate fuel for an advanced nuclear fuel recycle. In this report, influence of Np on the sintering behavior, phase separation behavior of MOX fuel pellets and the homogeneity of MOX fuel pellets were evaluated. It was observed that the high Np containing pellets had a low sintered density and the microstructure changes of the pellets during the sintering were slow compared with MOX without Np. The pellets were also analyzed via Ceramography, X-ray diffraction measurement and an electron probe microanalysis. The phase separation behavior of MOX with Np was similar to that of MOX. The homogeneity of the pellet produced with this experiment was acceptable to the fuel specification.
Morimoto, Kyoichi; Kato, Masato; Kono, Shusaku; Sugata, Hiromasa*; Sunaoshi, Takeo*
Abstract, PB63, (PB63), 0 Pages, 2003/00
Shigetome, Yoshiaki; Kono, Shusaku; Hellwig, C.*; Heimgartner, P.*
Proceedings of International Conference on Advanced Nuclear Energy and Fuel Cycle Systems (GLOBAL 2003) (CD-ROM), p.1342 - 1347, 2003/00
Ozawa, Takayuki; Abe, Tomoyuki; Kono, Shusaku; Franz Ingo*; Hannu Wall*
P.279, P. 279, 2002/00
; Kono, Shusaku; Ono, Kiyoshi
PROCEEDINGS(058), 0 Pages, 2001/00
Kamimura, Katsuichiro; Yano, Soichiro; Kono, Shusaku; Kato, Masato; Morimoto, Kyoichi; Morihira, Masayuki; Kikuchi, Keiichi
PNC TN8410 97-067, 457 Pages, 1997/02