24P101-P
Design of a movable material probe system for PWI study in JT-60SA
JT-60SAにおけるプラズマ・壁相互作用研究のための試料搬送装置設計検討
Suguru Masuzaki1, Masayuki Tokitani1, Mitsutaka Miyamoto2, Yuji Nobuta3, Yoshio Ueda4,Noriyasu Ohno5, Mizuki Sakamoto6, Naoko Ashikawa1, Tomohide Nakano7 and Kiyoshi Itami7
増崎 貴1, 宮本光貴2，信太祐二3，上田良夫4, 大野哲靖5，
坂本瑞樹6，時谷政行1，芦川直子1，仲野友英7，伊丹 潔7
1

National Institute for Fusion Science, Oroshi 322-6 Toki 509-5292, Japan
核融合科学研究所 〒509-5292 土岐市下石町322-6
2
Shimane University, Nishikawadu-cho 1060 Matsue 690-8504, Japan
島根大学 〒690-8504 松江市西川津町1060
3Hokkaido University, Kita-13 Nishi-8 Kita-ku Sapporo 060-8628, Japan
北海道大学 〒060-8628 札幌市北区北13条西8丁目
4Osaka University, Yamadaoka 2-1 Suita 565-0871, Japan
大阪大学 〒565-0871 吹田市山田丘2-1
5Nagoya University, Chikusa-ku Nagoya 464-8603, Japan
名古屋大学 〒464-8603 名古屋市千種区不老町322-6
6Tsukuba University, Tennodai 1-1-1 Tsukuba 305-8577, Japan筑波大学 〒305-8577 つくば市天王台1-1-1
7Japan Atomic Energy Agency, Mukoyama 801-1 Naka 311-0193, Japan
日本原子力研究開発機構 〒311-0193 那珂市向山801-1

A design of the movable material probe system for JT-60SA is proposed. The system provides theopportunity for inserting material specimens and diagnostics into the plasma vacuum vessel, and forspecimens changing during experimental campaign. The system will consist of manipulator, gate-valves,
working chamber and pumps. The system is under consideration to be installed in a bottom port. It willcontribute to plasma-wall interaction studies in JT-60SA.

1. Introduction
Understanding of plasma-wall interaction(PWI) in fusion devices is a crucial issue fordesign of fusion reactor. Two ways of PWI
studies have been conducted in present fusion
devices. One is post-mortem analysis of plasma
facing components and/or material specimens
after opening vacuum vessel to the atmosphere[1], and the other is material specimens exposure
to plasma using manipulator of material probe
system. In the former case, all PWIs on thecomponents and specimens during experimental
campaign are integrated. On the other hand, in thelatter case, PWIs in different plasma conditions
can be distinguished, and various PWI
experiments can be conducted if the materialprobe system has gate-valves and pumps. Suchsystems are utilized in several present fusion
devices,suchasLHD[2],DIII-D[3],ASDEX-Upgrade[4] and TEXTOR[5], andcontribute to PWI studies. In JT-60SA, a movablematerial probe system is under consideration to
be installed. Feasibility of this system has beenstudied.
In this presentation, a design of the material

probe system for JT-60SA will be shown.
2. Movable material probe system
The movable material probe system is planned to
be installed in JT-60SA from a bottom port in thetoroidal section P-10 as shown in Fig. 1. Material
specimens will be inserted into the plasma vacuum
vessel from the “cover for pipe connection” which
is located above the outer baffle. There is arectangular slot for the material probe system on thecover, and the size is 60mm in the toroidal direction
and 170mm in the radial direction. This slot’s sizeis the limit of the size of the head of thecover for pipe connection
material probe

outebaffle
vertical target

Fig. 1 The position of the port in a poloidal cross-sectionin JT-60SA in which the material probe system will beinstalled.

3. Summary
A design of the movable material probe system
for JT-60SA was proposed. It can insert various
material specimens into the scrape-off layer plasma.
The probe head is replaceable, and various designof the head should be done for various PWI
experiment.
Acknowledgments
This work was supported by JT-60 researchcollaboration.

1.56 mcryostat6.02 mvacuumvessel4.29 mgate-valveschamberfloor levelpumps

fast moving part
10 m

manipulator. Figure 2 shows the overall view of themovable material probe system. The system isequipped with gate-valves and pumps (cryo-pumpand turbo-pump), and the material specimens canbe changed more than once in the “chamber” during
an experimental campaign without opening theplasma
vacuum vessel. JT-60SA is asuper-conducting device, and it has cryostat forsustaining
liquid-He
temperatureofsuper-conducting equipment. Therefore, thedistance between the vacuum-atmosphere interface
ports and plasma is long. The moving line of themanipulator is shown by the red arrow in the figure.
The top of the manipulator can reach to thescrape-off layer plasma, and its maximum movinglength is about 5.9 m. In this design, welding
bellows are joined in series to enable the longstroke. About 10 m long bellows is necessary for it.
From the basement floor to the first floor level isalmost same distance as the necessary bellows
length. The pumps are put in the existing pit underthe bottom port. Two air-motors drive themanipulator with gear sets and ball-screws. One
motor drives fast moving part which moves fromthe chamber to the entrance of the vacuum vessel,
and the moving length is 4.29 m. Another motor
drives slow moving part which moves inside thevacuum vessel and is required position control, andthe maximum moving length is 1.56 m.
The probe head will be replaceable unit. The
design of the probe head depends on the purpose ofexperiment. Both water cooling and heater for
specimen are necessary for various PWIexperiments.

air-motor

slow moving partbasement
floor

Fig. 2 Overall view of the movable material probe
system.

References[1] For example, E. Tsitrone et al: Nucl. Fusion 49(2009) 075011.
[2] M. Tokitani et al: Nucl. Fusion 45 (2005) 1544.
[3] C.P.C Wong et al: J. Nucl. Mater. 363-365 (2007)
276.
[4] K. Krieger et al: J. Nucl. Mater. in press.
[5] J. W. Coenen et al: Nucl. Fusion 51 (2011) 083008.