Commissioning and Testing of a new 4.5K Cold Box for JLab Cryogenic Test Facility

[摘要] A new 4.5K cold box at Jefferson Lab (JLab) Cryogenic Test Facility (CTF) was recently installed and commissioned to upgrade the existing 4.5 K refrigeration system and work in parallel with the existing 4.5 K cold box. This new 4.5 K cold box is equipped with two turbo-expanders and, at its maximum capacity condition, it is expected to support at least 6.6 g/s of helium liquefaction or 650 W of refrigeration at 4.5 K. It can also handle up to 10 g/s 30 K return flow for 2 K refrigeration recovery that supports cryo-module and superconducting cavity testing. Performances of the cold box at its maximum capacity conditions as well as several other operating modes were tested for acceptance. We will briefly review the new 4.5 K cold box design features and discuss the commissioning and performance testing results.

[发布机构] Thomas Jefferson National Accelerator Facility, Newport News; VA; 23606, United States^1

[效力级别] 物理学 [学科分类] 材料科学（综合）

[关键词] Cold boxes;Cryogenic test facility;Jefferson Lab;Operating modes;Performance testing;Refrigeration system;Return flow;Superconducting cavities