Development of bearing units used in the rotating shaft system for power generation in the JAEA-Tokai Tandem accelerator

Otokawa, Yoshinori; Matsuda, Makoto; Abe, Shinichi

JAEA-Technology 2022-037, 23 Pages, 2023/03

JAEA-Technology-2022-037.pdf:5.38MB

Bearing units of rotating shaft system for power generation in the JAEA-Tokai Tandem accelerator had a short operating life from the beginning of the accelerator installation, and even after replacing the bearing unit, early failures often occurred. Therefore, the quantity and frequency of replacement are large, and a lot of time is spent in regular maintenance performed by opening the accelerator pressure vessel, and solving this problem has been a long-standing concern. As a result of considering the cause of this early failure, it was considered that the load caused by parallel, angular, and axial misalignment of the upper and lower bearing units was the cause. In order to solve this problem, we have developed a bearing unit having metal disc-spring couplings in the upper and lower flanges to allow for parallel, angular, and axial misalignment of bearing units. As a result, it is now possible to allow variations in the distance between castings and parallel, angular, and axial misalignment of the upper and lower bearing units. By installing the developed new bearing unit on the rotating shaft system and making improvements while continuing to use it in actual operation, we succeeded in reducing the early failure and extending the operating life by more than double. With this development, the maintenance time has been reduced to one week by reducing the number of replacing the bearing unit. In addition, we have realized one regular maintenance that was carried out about three times a year, and as a benefit, we were able to reduce the amount of sulfur hexafluoride (SF) gas, which is a greenhouse gas, to about 3350% per year. We describe about development of new bearing units and these maintenance status from 2006 to 2020.

Present status of JAEA-Tokai tandem accelerator

Matsuda, Makoto; Tayama, Hidekazu; Ishizaki, Nobuhiro; Kabumoto, Hiroshi; Nakamura, Masahiko; Kutsukake, Kenichi; Otokawa, Yoshinori; Asozu, Takuhiro; Matsui, Yutaka; Abe, Shinichi

Proceedings of 18th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.394 - 398, 2021/10

no abstracts in English

Present status of JAEA-Tokai tandem accelerator

Matsuda, Makoto; Osa, Akihiko; Ishizaki, Nobuhiro; Tayama, Hidekazu; Kabumoto, Hiroshi; Nakamura, Masahiko; Kutsukake, Kenichi; Otokawa, Yoshinori; Asozu, Takuhiro; Matsui, Yutaka; et al.

Proceedings of 16th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.1270 - 1273, 2019/07

https://www.pasj.jp/web_publish/pasj2019/proceedings/index_abstracts.html

The JAEA-Tokai tandem accelerator was operated over a total of 138 days, and delivered 16 different ions to the experiments in the research fields of nuclear physics, nuclear chemistry, atomic physics, solid state physics and radiation effects in material in FY2018. Maximum acceleration voltage was 16.6 MV. A new beam attenuator was installed at the entrance beam line of the tandem accelerator to facilitate control of the beam current and minimize stripper foil consumption. The main maintenance items included replacing the pellet chain used for about 68,000 hours and the drive motor for the high voltage terminal generator used for about 9 years. A fault has occurred in the building's oxygen deficiency monitor. This paper describes the operational status of the accelerators and the major technical developments of our facility.

The Failure example of the Tokai tandem accelerator

Matsuda, Makoto; Abe, Shinichi; Ishizaki, Nobuhiro; Tayama, Hidekazu; Nakanoya, Takamitsu; Kabumoto, Hiroshi; Nakamura, Masahiko; Kutsukake, Kenichi; Otokawa, Yoshinori; Asozu, Takuhiro; et al.

Dai-27-Kai Tandemu Kasokuki Oyobi Sono Shuhen Gijutsu No Kenkyukai Hokokushu, p.142 - 145, 2015/03

no abstracts in English

Present status of JAEA-Tokai tandem accelerator and booster

Matsuda, Makoto; Osa, Akihiko; Abe, Shinichi; Ishizaki, Nobuhiro; Tayama, Hidekazu; Nakanoya, Takamitsu; Kabumoto, Hiroshi; Nakamura, Masahiko; Kutsukake, Kenichi; Otokawa, Yoshinori; et al.

Proceedings of 10th Annual Meeting of Particle Accelerator Society of Japan (Internet), p.307 - 309, 2014/06

http://www.pasj.jp/web_publish/pasj10/proceedings/PDF/SSFP/SSFP03.pdf

no abstracts in English

The Earthquake-damage of the JAEA-Tokai tandem accelerator

Matsuda, Makoto; Osa, Akihiko; Abe, Shinichi; Ishizaki, Nobuhiro; Tayama, Hidekazu; Nakanoya, Takamitsu; Kabumoto, Hiroshi; Nakamura, Masahiko; Kutsukake, Kenichi; Otokawa, Yoshinori; et al.

Dai-24-Kai Tandemu Kasokuki Oyobi Sono Shuhen Gijutsu No Kenkyukai Hokokushu, p.51 - 54, 2011/07

no abstracts in English

Present status of JAEA-Tokai tandem accelerator facility

Matsuda, Makoto; Ishii, Tetsuro; Tsukihashi, Yoshihiro; Hanashima, Susumu; Abe, Shinichi; Osa, Akihiko; Ishizaki, Nobuhiro; Tayama, Hidekazu; Nakanoya, Takamitsu; Kabumoto, Hiroshi; et al.

Dai-22-Kai Tandemu Kasokuki Oyobi Sono Shuhen Gijutsu No Kenkyukai Hokokushu, p.10 - 14, 2010/01

no abstracts in English

Present status of JAEA-Tokai tandem accelerator

Matsuda, Makoto; Sataka, Masao; Takeuchi, Suehiro; Tsukihashi, Yoshihiro; Hanashima, Susumu; Abe, Shinichi; Osa, Akihiko; Ishizaki, Nobuhiro; Tayama, Hidekazu; Nakanoya, Takamitsu; et al.

JAEA-Conf 2008-005, p.42 - 45, 2008/03

https://doi.org/10.11484/jaea-conf-2008-005

In FY2006, a tandem accelerator was operated for 201days. The maximum voltage was 18 MV and the accelerated ion species was 19 elements (26 nuclides). As the trouble case which occurred previous year, the change of the beam shape occurred often in the injection beam line of the tandem accelerator. The cause was the contact failure of the pole connector of the electrostatics quadrupole lens. Generally, it was difficult to confirm the connection status of the opened pole but we specified a connection abnormal part by the capacitive coupling method. This technique is useful technology which can be applied to the other electrostatics optics elements. Because the charging electric current flowed only about usual about 60% and the terminal voltage became unstable, we opened a tank and checked the charging system. As a result, a problem was confirmed to the damaging of resistance and the installation of the cable. In the seminar, the operation, maintenance and the accelerator development of the tandem accelerator in FY2006 are described.

Present status of JAEA-Tokai tandem accelerator

Matsuda, Makoto; Takeuchi, Suehiro; Tsukihashi, Yoshihiro; Hanashima, Susumu; Abe, Shinichi; Osa, Akihiko; Ishizaki, Nobuhiro; Tayama, Hidekazu; Nakanoya, Takamitsu; Kabumoto, Hiroshi; et al.

Proceedings of 3rd Annual Meeting of Particle Accelerator Society of Japan and 31st Linear Accelerator Meeting in Japan, p.275 - 277, 2006/00

no abstracts in English

Status report on the JAERI tandem accelerator facility

Matsuda, Makoto; Takeuchi, Suehiro; Tsukihashi, Yoshihiro; Horie, Katsuzo; Ouchi, Isao; Hanashima, Susumu; Abe, Shinichi; Ishizaki, Nobuhiro; Tayama, Hidekazu; Nakanoya, Takamitsu; et al.

Dai-17-Kai Tandemu Kasokuki Oyobi Sono Shuhen Gijutsu No Kenkyukai Hokokushu, p.1 - 4, 2004/00

no abstracts in English