Huang Shuhong

Experimental study on the damage of a 125 MW steam turbine rotor

Abstract A study on the damage of a 125 MW steam turbine rotor was carried out through a series of experiments. The unit was in service from May 1992. After 10 years of operation, the integrity of the rotor was threatened by material deterioration caused by fatigue and creep damage at certain critical locations. In this study, sophisticated thermoplastic finite element analysis (FEA) was employed to establish the transient strain/stress and temperature fields of the rotor during the experiments. Based on the results of the FEA and damage-evaluating model, the life loss of the rotor was evaluated and the residual service life of the rotor calculated. The study concluded that changing the running schedule threatened the safety and reliability of the turbine rotor and would reduce its service life, but five more years of safe operation of the rotor could be guaranteed. Some operational suggestions are also presented in this paper, which help to decrease damage during operation.