Performance validation tests on 80K bubble type of shields for SST-1

• Published in: Cryogenics (Guildford) 2012-12, Vol.52 (12), p.685-688
• Main Authors: Sonara, Dashrath, Tanna, Vipul, Panchal, Rohit, Bairagi, Nitin, Gupta, Manoj K., Gupta, Naresh C., Patel, Ketan, Nimavat, Hiren, Srikanth, G.L.N., Sharma, Rajiv, Shah, Pankil, Khan, Ziauddin, Pathan, Firoz khan, Yuvakiran, Paravastu, George, Siju, Raval, Dilip C., Parekh, Tejas, Sharma, Aashoo, Pradhan, Subrata
• Format: Article
• Language: English
• Subjects: Embossed shields; Heat loads; Leakages; SST-1; Temperature uniformity
• ISSN: 0011-2275; 1879-2235
• DOI: 10.1016/j.cryogenics.2012.04.007

► We introduce 80 K bubble type thermal shield for SST-1. ► Experimental set-up for cryogenic test on SST-1 thermal shields. ► Temperature profile across all bubble panel is recorded for entire cool-down Period. ► Cryogenic performance on SST-1 80 K thermal shield is validated. The 80K thermal shields of Steady State Superconducting Tokamak (SST-1) minimize the steady state heat loads on the superconducting magnet system at 4.5K from ambient. Uniform temperature, vacuum and cryo compatibility is desired for the 80K shields. In order to meet these requirements, the bubble/embossed type of design concept is adopted. This design ensures lower pressure drop and better temperature uniformity within ±5K. Special attention has been given for preventing direct radiation on the magnet system. As part of performance validation tests, a group of 80K thermal shields have undergone rigorous testing protocols and procedures. The temperature distribution, helium leak tightness and insulation resistance tests have been carried out for SST-1 thermal shields before final assembly of the machine. The test design, procedures and results of the 80K thermal shields will be discussed in this paper.