Recent operational experience of cryogenic system for sst-1

Prior to the SST-1 device integration, all the TF as well as some of the PF superconducting coils were tested in a dedicated cryostat in respective rated parameters. Many of new auxiliary cryo sub-systems were made functional as per the design parameters prior to SST-1 cooldown activities. Recently the cool-down attempts of SST-1 machine has been carried out for the engineering commissioning. SST-1 cryogenics system comprises of cryogenic helium and liquid nitrogen systems. IPR has an operational 1.3 kW at 4.5 K custom designed cryogenic helium refrigerator-liquefier (HRL). In order to minimize the static heat loads from ambient (300 K), double embossed type thermal shields system has been provided. The major new auxiliary cryo-systems include the current feeders system (CFS) and 80 K thermal shields system. These auxiliary cryo-systems have demonstrated their rated performance during the recent cool-down of SST-1. This paper will elaborate the recent experience of SST-1 cool-down results.