基于减压降温原理的超流氦获取真空机组的研制

Development of superfluid helium vacuum unit based on decompression and cooling

南方先进光源研究测试平台(SAPS-TP)为了给超导腔提供2 K测试环境,采用在氦池入口抽真空至饱和蒸气压的方式来获取2 K超流氦。研制一套减压降温真空机组用来抽取真空,详细介绍了设计和选型计算,并借鉴各大型2 K低温系统的使用经验,进行了优化。已完成20余次超导腔的性能测试,真空机组运行稳定,氦池压力、温度和液位等参数的控制精度达到设计指标。运行测试结果表明,所研制的减压降温真空机组性能满足设计要求。

2 K superfluid helium is obtained by vacuum pumping the helium to saturated va-por pressure at the entrance of the helium pool in Southern Advanced Photon Source Test Platform(SAPS-TP)in order to provide a cryogenic environment for the superconducting cavity.A set of decompression and cooling vacuum unit is developed for vacuum pumping.The design and selec-tion calculation are discussed in detail.The operation experience of various large-scale 2 K cryo-genic systems is used for reference and optimization.The performance test of the superconducting cavity has been completed for more than 20 times,and the vacuum unit exhibits a stable perform-ance and accurate control of the helium pool pressure,temperature and liquid level.Test results show that the performance of the developed vacuum unit meets the design requirements.