Thermal stress analysis for rotor of 600MW supercritical steam turbine

With the increase of steam turbine´s steam parameter and the participation in peak-load adjustment of power grid more and more frequently, the stress of the turbine´s rotor is becoming increasingly complex, and the alternating thermal stress has became the major factor reducing its life. This paper used a 600MW supercritical steam turbine´s rotor as the research object, and analyzed the variation of thermal stress in the warm starting-up process. In this paper the analysis based on the operating data measured from actual operation and calculate the variations of the temperature field and stress field during the process of warm starting-up with the method of thermal-structure direct interaction analysis by Ansys. By analyzing the results, it proves that the maximum stress of the rotor is in the first stage of the intermediate pressure casing, and it is the main factor restricting the velocity of steam turbine´s starting-up process. This result which calculated and analyzed by finite element method can be a theoretical basis for the optimal operation and online monitoring of turbine units.