High reliability and long life endurance are very important factors in the operation of large steam turbines for nuclear power plant (NPP). The low cycle fatigue (LCF) is necessary take into account problem in the design of turbine component. Thus the calculation method and assessment criterion of LCF are important for the design and development of the low pressure (LP) inner-casing.
The main activity of this study was focus on the research of the low cycle fatigue in 26m2 LP inner-casing of steam turbines for NPP, which is manufactured by Shanghai Electric Power Generation Equipment Co., Ltd: STP. And detailed calculation method and assessment criterion combined with FEA analysis, fatigue curve and linear cumulative damage theory are developed to judge the life of the LP inner-casing, The approach is applied in the process of the design work of large steam turbine inner-casing.