Details

Autor(en) / Beteiligte

• Natsume, K
• Murakami, H
• Kizu, K
• Yoshida, K
• Koide, Y

Titel

Cryogenic thermometry for refrigerant distribution system of JT-60SA

Ist Teil von

• IOP conference series. Materials Science and Engineering, 2015-12, Vol.101 (1), p.12113-12120

Ort / Verlag

Bristol: IOP Publishing

Erscheinungsjahr

2015

Quelle

EZB Electronic Journals Library

Beschreibungen/Notizen

• JT-60SA is a fully superconducting fusion experimental device involving Japan and Europe. The cryogenic system supplies supercritical or gaseous helium to superconducting coils through valve boxes or coil terminal boxes and in-cryostat pipes. There are 86 temperature measurement points at 4 K along the distribution line. Resistance temperature sensors will be installed on cooling pipes in vacuum. In this work, two sensor attachment methods, two types of sensor, two thermal anchoring methods, and two sensor fixation materials have been experimentally evaluated in terms of accuracy and mass productivity. Finally, the verification test of thermometry has been conducted using the sample pipe fabricated in the same way to the production version, which has been decided by the comparison experiments. The TVO sensor is attached by the saddle method with Apiezon N grease and the measurement wires made of phosphor bronze are wound on the pipe with Stycast 2850FT as the thermal anchoring. A Cernox sensor is directly immersed in liquid helium as a reference thermometer during the experiment. The measured temperature difference between the attached one and reference one has been within ±15 mK in the range of 3.40-4.73 K. It has satisfies the accuracy requirement of 0.1 K.