我们根据任务需要,开展了液氢阀门外绝热的研究。分析与比较表明:聚氨酯泡沫与其它外绝热材料相比有很多优异性能,但也有不足之处。采用复合式绝热结构可扬长避短,取得令人满意的综合性能。文中对绝热结构、厚度、密度等有关技术问题作了分析与阐述。数年的实际应用说明:液氢阀等极低温设备采用聚氨酯泡沫塑料复合外绝热是行之有效的,完全可满足设计要求。 According to the needs of our mission, we carried out research on the thermal insulation of liquid hydrogen valves. Analysis and comparison show that polyurethane foam has many excellent properties compared with other external insulation materials, but there are also some shortcomings. The use of composite insulation structure can avoid weaknesses and achieve satisfactory overall performance. In this paper, the technical problems of heat insulation structure, thickness and density are analyzed and elaborated. Years of practical application Note: Very low temperature liquid hydrogen valve and other equipment with polyurethane foam composite insulation is effective, fully meet the design requirements.