汽轮机高温部件总寿命的计算方法及工程验证

Total Life Calculation for High Temperature Components of Steam Turbines and Its Engineering Verification

提出了大型汽轮机高温部件在低周疲劳与蠕变交互作用下总寿命的计算方法。介绍了汽轮机高温部件的低周疲劳裂纹萌生寿命、蠕变裂纹萌生寿命、低周疲劳裂纹扩展寿命与蠕变裂纹扩展寿命的计算方法,给出了汽轮机高温部件在低周疲劳与蠕变交互作用下裂纹萌生日历寿命、裂纹扩展日历寿命与总寿命的计算方法和总寿命的评定方法,并通过2台超临界600 MW汽轮机高压内缸外表面寿命薄弱部位总寿命的计算分析进行工程验证。结果表明:1号汽轮机高压内缸总寿命计算的相对误差为4.12%,2号汽轮机高压内缸总寿命计算的相对误差为-0.48%,计算结果符合电站服役的工程实际。

Total life calculation methods were proposed for high-temperature components of large steam turbines under the action of low cycle fatigue and creep,including the methods for low cycle fatigue crack initiation life,creep crack initiation life,low cycle fatigue crack propagation life and creep crack propagation life,as well as for crack initiation calendar life,crack propagation calendar life and the total life of high temperature components under the combined action of low cycle fatigue and creep.Simultaneously,an assessment method was also presented for the total life.Above methods were verified through calculation analysis on weak regions of outer surfaces in high-pressure inner cylinder of two 600 MW supercritical steam turbines.Results show that the relative error calculated for the total life of high-pressure inner cylinder of turbine 1 is 4.12%,and that of turbine 2 is-0.48%,satisfying the requirements of actual applications.