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Kawahara, Takahiro; Suda, Shoya; Fujikura, Toshiki; Masai, Seita; Omori, Kanako; Mori, Masakazu; Kurosawa, Tsuyoshi; Ishihara, Keisuke; Hoshi, Akiko; Yokobori, Tomohiko
JAEA-Technology 2023-020, 36 Pages, 2023/12
JAEA-Technology-2023-020.pdf:2.79MB
We have been storing drums containing radioactive waste (radioactive waste packages) at waste storage facilities. We have been managing radioactive waste packages along traditional safety regulations. However, over 40 years has passed from a part of them were brought in pit-type waste storage facility L. Most of them are carbon steel 200 L drums, and surface of them are corroded. For better safety management, we started to take drums out from the pit and inspect them in FY 2019. After each inspection, we repair them or remove the contents of the drum and refill new drums if necessary. In this report, we will introduce the planning, the review of the plan, and the trial operation of this project.
Tamaoki, Yuichi; Omori, Tsuyoshi; Fujishima, Tadatsune; Mizukoshi, Yasutaka; Sakamoto, Naoki
Proceedings of 53rd Annual Meeting of Hot Laboratories and Remote Handling Working Group (HOTLAB 2016) (Internet), 6 Pages, 2016/11
Post irradiation examinations are conducted in hot laboratories in Oarai Research and Development Center of the Japan Atomic Energy Agency in order to develop fuels and materials for fast reactors. These facilities, the majority of which were constructed in the 1970s, have accumulated operating experience over a period of more than 40 years. Continuous operational safety requires the maintenance of important equipment such as electronic devices, manipulators, in-cell cranes, as well as air conditioning and ventilation systems. A method for the periodic safety review for hot laboratories based on the periodic safety review method employed for preventive maintenance at commercialized power reactors in Japan has been developed. In this paper, the status of implementation of the periodic safety review for hot laboratories using the safety review method are introduced.
Toyomori, Yuka*; Tsuji, Satoru*; Mitsuda, Shinobu*; Okayama, Yoichi*; Ashida, Shiomi*; Mori, Atsunori*; Kobayashi, Toru; Miyazaki, Yuji; Yaita, Tsuyoshi; Arae, Sachie*; et al.
Bulletin of the Chemical Society of Japan, 89(12), p.1480 - 1486, 2016/09
Times Cited Count：8 Percentile：29.47(Chemistry, Multidisciplinary)Fujishima, Tadatsune; Mizukoshi, Yasutaka; Sakamoto, Naoki; Omori, Tsuyoshi
Hozengaku, 13(2), p.115 - 125, 2014/07
In order to develop fuels and materials for fast reactors, five hot laboratories as a facility using nuclear materials for post irradiation examination (PIE) are now in operation at the Oarai Research and Development Centre of Japan Atomic Energy Agency. More than 30 years have passed since the first hot run of these facilities was started, and it has been indispensable to maintain the principal equipment for continuous safe operation. For application to preventive maintenance and the safe operation, a new safety review method that could be applied for these facilities was developed by modification of periodic safety review tools using for Japanese commercialized power reactors. Effective repair or replacement of equipment before malfunction have been performed and the priority for preventive maintenance could be appropriately determined for stable management of hot facility operations by the developed method.
Ishihara, Masahiro; Kimura, Nobuaki; Takemoto, Noriyuki; Ooka, Makoto; Kaminaga, Masanori; Kusunoki, Tsuyoshi; Komori, Yoshihiro; Suzuki, Masahide
Proceedings of 5th International Symposium on Material Testing Reactors (ISMTR-5) (Internet), 7 Pages, 2012/10
The JMTR has been utilized for fuel/material irradiation examinations of LWRs, HTGR, fusion reactor as well as for RI productions. The refurbishment of the JMTR was started from the beginning of JFY 2007, and finished in March 2011 as planned schedule. Unfortunately, at the end of the JFY 2010 on March 11, the Great-Eastern-Japan-Earthquake occurred, and functional tests before the JMTR restart were delayed by the earthquake. Moreover, a detail inspection found some damages such as small cracks in the concrete structure, ground sinking around the reactor building. Consequently, the restart will delay from June 2011. Now, the safety evaluation of the facility after the earthquake disaster is being carried out aiming at the restart of the JMTR. The renewed JMTR will be started from JFY 2012 and operated for a period of about 20 years until around JFY 2030. The usability improvement of the JMTR is also discussed with users as the preparations for re-operation.
Nakamura, Kinya*; Ogata, Takanari*; Kikuchi, Hironobu; Iwai, Takashi; Nakajima, Kunihisa; Kato, Tetsuya*; Arai, Yasuo; Uozumi, Koichi*; Hijikata, Takatoshi*; Koyama, Tadafumi*; et al.
Nihon Genshiryoku Gakkai Wabun Rombunshi, 10(4), p.245 - 256, 2011/12
Sodium-bonded metallic fuel elements were fabricated for the first time in Japan for the irradiation test in the experimental fast test reactor JOYO. U-20Pu-10Zr fuel slugs of 200 mm in length and approximately 5 mm in diameter were fabricated in a small-scale injection casting furnace. Each fuel slug was loaded into the ferritic martenstic stainless steel (PNC-FMS) cladding tube with the sodium thermal bond, thermal insulator and reflector in a helium gas atmosphere glove box. After top-end plug welding to the cladding tube and heat treatment of the welding area, each fuel element was subjected to the sodium bonding process. After the inspection such as element length, gas plenum length and helium-leak tightness, six metallic fuel elements are transported to the JOYO site for the coming irradiation test.
Fujishima, Tadatsune; Sakamoto, Naoki; Mizukoshi, Yasutaka; Amagai, Tomio; Omori, Tsuyoshi
Nihon Hozen Gakkai Dai-5-Kai Gakujutsu Koenkai Yoshishu, p.388 - 392, 2008/07
no abstracts in English
Yamamoto, Masanobu; Anami, Shozo*; Ezura, Eiji*; Hasegawa, Katsushi; Hara, Keigo*; Horino, Mitsuyoshi*; Nomura, Masahiro; Omori, Chihiro*; Schnase, A.; Shimada, Taihei; et al.
Proceedings of 5th Annual Meeting of Particle Accelerator Society of Japan and 33rd Linear Accelerator Meeting in Japan (CD-ROM), p.358 - 360, 2008/00
The beam commissioning has been started at the J-PARC RCS in October 2007, and the beam acceleration and the extraction at 3 GeV has been succeeded. Some longitudinal bunch gymnastics has been tested toward the high intensity operation, one of the issues is arriviating the space charge effect at the injeciton. Since the multi-turn injection scheme is employed at the RCS, the electric charge density of the bunch near the center of the RF bucket tends to be high with only normal fundamental RF capture. Some schemes such as adding 2nd higher harmonic RF, the momentum offset and the phase offset of the 2nd one are simulated by longitudinal particle tracking code to make the bunching factor low. The comparison between the beam test result and the particle tracking simulation is described.
Mori, Masahiro; Shoji, Teruaki; Araki, Masanori; Saito, Keiji*; Senda, Ikuo; Omori, Junji*; Sato, Shinichi*; Inoue, Takashi; Ono, Isamu*; Kataoka, Takahiro*; et al.
Nihon Genshiryoku Gakkai-Shi, 44(1), p.16 - 89, 2002/01
no abstracts in English
Yoshitake, Tsunemitsu; Omori, Tsuyoshi; Sakamoto, Naoki; Ukai, Shigeharu
PNC TN9410 96-281, 81 Pages, 1996/09
The estimation of the life of fuel claddings at thermal transient event is important for evaluating of the fuel claddings validity under the loss of coolant flow (LOF) accident. In order to estimate the life time of the fuel claddings corresponding to any temperature rising condition, the instrumental technique was first improved in the post-irradiation examination and the temperature-transient-to-burst tests were extensively conducted on PNC316 claddings which were irradiated in JOYO as a fuel test assembly PFC030M and a driver fuel assembly PFD304. The life time evaluation of the irradiated PNC316 fuel claddings was carried out, based on these test results. The results obtained in this work are as follows; (1) As a result of the improvement in the temperature-transient-to-burst testing, the diametral change data and higher hoop stress data were obtained. And the highly accurate measurement of rupture temperature was also achieved. (2) The temperature-transient-to-burst test results showed that the rupture temperature of the irradiated PNC316 cladding was equal to that of unirradiated one up to present neutron fluence in LOF stress condition. It was indicated that the temperature-transient-to-burst property of PNC316 was not influenced by irradiation in lower hoop stress region. (3) The life time of the irradiated PNC316 cladding at any thermal transient condition was evaluated by means of LMP-Life Fraction Rule method. Consequently, the result of estimation for failure temperature of heavily irradiated PNC316 showed the possibility for rising the design limit of the cladding highest temperature for MONJU.
Tachibana, Toshimichi; Itaki, Toshiyuki; Yamanouchi, Sadamu; Omori, Tsuyoshi*
Journal of Nuclear Science and Technology, 22(2), p.155 - 157, 1985/00
Times Cited Count：19 Percentile：92.69(Nuclear Science & Technology)None
Kasugai, Atsushi; Sakamoto, Keishi; Takahashi, Koji; Kajiwara, Ken; Ikeda, Yukiharu; Komori, Shinji; Kobayashi, Noriyuki; Kariya, Tsuyoshi*; Minami, Ryutaro*; Mitsunaka, Yoshika*
no journal, ,
no abstracts in English
Mizukoshi, Yasutaka; Fujishima, Tadatsune; Sakamoto, Naoki; Amagai, Tomio; Omori, Tsuyoshi
no journal, ,
no abstracts in English
Fujishima, Tadatsune; Mizukoshi, Yasutaka; Sakamoto, Naoki; Amagai, Tomio; Omori, Tsuyoshi
no journal, ,
no abstracts in English
Fujishima, Tadatsune; Amagai, Tomio; Mizukoshi, Yasutaka; Sakamoto, Naoki; Omori, Tsuyoshi
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no abstracts in English
Amagai, Tomio; Fujishima, Tadatsune; Mizukoshi, Yasutaka; Sakamoto, Naoki; Omori, Tsuyoshi
no journal, ,
In the site of O-arai research and development center of Japan Atomic Energy Agency (JAEA), five hot laboratories for post-irradiation examination and development of plutonium fuels are operated more than 30 years. A safety review method for preventive maintenance on these hot laboratories includes test facilities and devices are established in 2003. After that, the safety review of these facilities and devices are done and taken the necessary maintenance based on the results in each year. In 2008, 372 test facilities and devices in these hot laboratories were checked and reviewed by this method. As a results of the safety review, repair issues of 38 facilities of above 372 facilities were resolved. This report shows the review results and maintenance experiences based on the results.
Fujishima, Tadatsune; Sakamoto, Naoki; Mizukoshi, Yasutaka; Amagai, Tomio; Omori, Tsuyoshi
no journal, ,
no abstracts in English
Fujishima, Tadatsune; Omori, Tsuyoshi
no journal, ,
no abstracts in English
Nagata, Hiroshi; Yamaura, Takayuki; Naka, Michihiro; Kawamata, Kazuo; Izumo, Hironobu; Hori, Naohiko; Nagao, Yoshiharu; Kusunoki, Tsuyoshi; Kaminaga, Masanori; Komori, Yoshihiro; et al.
no journal, ,
Conceptual design of the high-performance and low-cost next generation materials testing reactor which will be assumed to introduce to the nuclear power plant introduction country started from 2010 in the JAEA. Japanese atomic energy-related companies participate in this project, and this activity role as the environmental management and nuclear human resource development for the new research reactor designs. 10 MW thermal power by plate type fuel elements and swimming pool type was assumed as a design base. High safety, high cost performance, high reactor operation rate, high technology irradiation are targets of this conceptual design.
Izumo, Hironobu; Hori, Naohiko; Kaminaga, Masanori; Kusunoki, Tsuyoshi; Ishihara, Masahiro; Komori, Yoshihiro; Suzuki, Masahide; Kawamura, Hiroshi
no journal, ,
The refurbishment project of the JMTR was promoted with two subjects, the one was the replacement of reactor components, and the other was the construction of new irradiation facilities. On the replacement of reactor components, an investigation on aged components was carried out, for concrete structures, tanks, tubes in order to identify their integrity. After the investigation, some components were decided to replace from viewpoints of future maintenance and improvement of reliability. On the construction of new irradiation facilities, corresponding to the user's irradiation request, new irradiation facilities, such as for LWRs materials or fuels, were installed. Furthermore, new project was selected in order to install new irradiation facilities, such as for 
Mo production and PIE equipments. The new JMTR will contribute the promotion on research and development of the nuclear energy from basic to applied fields as an internationally utilized facility.
