国内外规范中尚无1——2型列管换热器温差应力的计算,本文提出该型设备温差应力的计算公式,为是否设立膨胀节提供判据。计算温差应力时按第一程和第二程分别进行考虑,导出两程分界处的转折点温度t_n与传热单元数NTU、水当量(热容量流率比)的关系。 There is no calculation of the temperature difference stress of 1--2 type tube heat exchanger at home and abroad norms. This paper puts forward the calculation formula of temperature difference stress of this type of equipment, and provides the criterion for setting expansion joint. The calculation of temperature stress is based on the first pass and the second pass respectively, and the relationship between the temperature t_n and the number of heat transfer units NTU, water equivalent (heat capacity flow rate) at the two-way boundary is derived.