针对国产改进型ＵＰ锅炉水冷壁经常爆漏的实际情况，分析了在ＵＰ锅炉中广泛使用的Φ２２×５．５ｍｍ四头内螺纹管的热敏感性。从多种角度计算了影响热敏感性强弱的因素，包括干度、热负荷、管段高度、进出口局部阻力等，讨论了热敏感性对锅炉运行的影响，对锅炉的设计和运行提出某些建议。 In view of the actual situation of frequent explosion of water wall of domestic advanced UP boiler, the thermal sensitivity of Φ22 × 5.5mm four-headed female pipe which is widely used in UP boiler is analyzed. The factors that affect the sensitivity of heat sensitivity are calculated from a variety of perspectives, including the dryness, heat load, pipe height, local resistance to import and export. The influence of heat sensitivity on boiler operation is discussed. The design and operation of the boiler are proposed Some suggestions.