DN800型低温泵的设计与实验

Design and experiment of DN800 cryopump

某型真空环境实验装置采用泵口法兰直径800 mm的低温真空泵作为解决方案,实现大抽速、无油洁净的抽空需求。该型低温真空泵采用2台GM制冷机作为制冷源,不需要低温液体辅助冷却。2台GM制冷机总计可以提供220 W@77 K、12 W@16 K的制冷量,超过了低温泵的系统热负荷,存在一定的富裕制冷量。在对该型低温泵的泵壳体、障板、吸附阵等关键部件的设计时,按照低温泵的相关理论公式进行计算求解,并综合考虑了结构强度、指标需求和工作裕度等因素,最后通过ANSYS仿真分析软件对温度场进行了模拟分析,模拟结果证实障板、吸附阵的设计满足工作要求。DN800型低温泵实测的最低温度为10.1 K,实测的降温时间195 min,实测氮气抽速为30000 L/s,实测氩气抽速为24000 L/s,实测氢气抽速为54000 L/s。

DN800 cryopump with 800 mm diameter was needed by certain type of vacuum environment experimental device to realize the evacuation demand of large pumping speed and oil-free clean.It used two GM cryocoolers as the refrigeration source and did not need cryogenic liquid auxiliary cooling.The two GM cryocoolers could provide cooling capacities of 220 W@77 K and 12 W@16 K,which exceeded the system heat load of the cryopump,and there was a certain rich cooling capacity.In the design of pump shell,barrier,adsorption array and other key components of the cryopump,according to the theoretical formula of cryopump,the structural strength,index requirements and working margin,finally through the ANSYS simulation analysis software,the simulation results confirm that the design of barrier and adsorption array meet the work requirements.The final experimental results of cooling time and pumping speed confirm that DN800 cryopump can meet the requirements of technical indicators.The measured minimum temperature of DN800 cryopump is 10.1 K,the measured cooling time is 195 min,the measured speed of nitrogen is 30000 L/s,the measured speed of argon is 24000 L/s,and the measured speed of hydrogen is 54000 L/s.