【摘 要】
：
氙气具有较低的电离能和较高的原子质量,是电推力器通常使用的推进剂.在地面进行电推力器真空试验时,需要采用真空抽气系统抽除真空容器内氙气,国内外早期电推力器大型真空试验设备,通常采用油扩散泵作为氙气主要抽气泵,近年来,随着制冷机的日臻完善,更洁净的制冷机低温泵得到迅速发展,在此类设备上逐渐代替了油扩散泵.兰州华宇航天技术应用有限责任公司根据兰州空间技术物理研究所的长寿面、高可靠性电推力器试验设备需求
【机 构】
：
兰州华宇航天技术应用有限责任公司 甘肃兰州 730000 兰州空间技术物理研究所,兰州730000
论文部分内容阅读
氙气具有较低的电离能和较高的原子质量,是电推力器通常使用的推进剂.在地面进行电推力器真空试验时,需要采用真空抽气系统抽除真空容器内氙气,国内外早期电推力器大型真空试验设备,通常采用油扩散泵作为氙气主要抽气泵,近年来,随着制冷机的日臻完善,更洁净的制冷机低温泵得到迅速发展,在此类设备上逐渐代替了油扩散泵.兰州华宇航天技术应用有限责任公司根据兰州空间技术物理研究所的长寿面、高可靠性电推力器试验设备需求,研制了大口径抽氙气低温泵.本文通过对氙气的冷凝性质进行分析,给出了低温泵抽除氙气的设计思路,并详细介绍了一种大口径抽氙气低温泵(有效抽气口径1250mm)的结构特征及详细设计.经测定,该低温泵对氙气有效抽速达28000L/s,较同口径普通低温泵,抽氙气速率增大1.4 倍,其性能完全满足了设备需求.
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