Research On Large-scale Steam Turbine Rotor's Brittleness Damage

To the embrittlement phenomenon of steam turbine rotor, this thesis calculated 300MW steam turbine rotor's transient temperature field of cold start-up using FEA method. The results indicate that the temperature of the last stages' center bore is only about 90℃ that is below FATT after cold start-up's 60 min. The conclusion that the last few stages should be paid attention to was made. Through the analysis on brittleness damage this thesis bring forward some suggestions and measures on the mode of operation and rising of rotate speed, increase of rotor's temperature and preventing rotor's brittleness damage. A residual life calculation method of assessing deteriorated rotor has been proposed. The mechanism and phenomenon of embrittlement and method of diagnoses has been systematically investigated. At last experimentation of diagnoses was designed by the method of electrochemistry.