Commissioning of cryogenic system for China Spallation Neutron Source

Cryogenic Engineering Conference 2017

材料科学;物理学

Ye, Bin^1,2 ; He, Chongchao^1,2 ; Li, Na^1,2 ; Ding, Meiying^1,2 ; Wang, Yaqiong^1,2 ; Yu, Zhang^1,2 ; He, Kun^1,2

China Spallation Neutron Source, Institute of High Energy Physics, Chinese Academy of Sciences, Dongguan

523803, China^1

Dongguan Institute of Neutron Science, Dongguan

523808, China^2

关键词: Acceptance testing;    China spallation neutron source (CSNS);    commissioning;    Cryogenic system;    Dangerous situations;    Helium refrigerators;    Refrigerating capacity;    Spallation neutron sources;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/278/1/012108/pdf
DOI  :  10.1088/1757-899X/278/1/012108

学科分类：材料科学（综合）

来源: IOP

【 摘 要 】

China Spallation Neutron Source(CSNS) cryogenic system provides supercritical cryogenic hydrogen to neutron moderators, including a helium refrigerator, hydrogen loop and hydrogen safety equipment. The helium refrigerator is provided by Linde with cooling capacity of 2200 W at 20 K. Hydrogen loop system mainly includes cryogenic hydrogen pipes, hydrogen circulator cold-box and accumulator cold-box. Cryogenic hydrogen pump, ortho-para convertor, helium-hydrogen heat-exchanger, hydrogen heater and accumulator are integrated in hydrogen circulation cold-box, and accumulator cold-box. Hydrogen safety equipment includes safety valves, rupture disk, hydrogen sensor, flame detector and other equipment to ensure that cryogenic system in dangerous situations will go down, vents, or takes other measures. The cryogenic system commissioning work includes four steps. First, in order to test the refrigerating capacity of refrigerator, when acceptance testing, refrigerator internal heater was used as thermal load. Second, using simulation load as heat load of moderator, hydrogen loop use helium instead of hydrogen, and cooled down to 20 K, then re-warming and test the leak detection of hydrogen loop system. Third, base on the step 2, using hydrogen as working medium, and optimized the control logic. Forth, cryogenic system with the moderators joint commissioning. Now, cryogenic system is connected with the moderators, and the forth step will be carried out in the near future.