| 摘要 |
PURPOSE:To rapidly evaluate residual life with good accuracy, by preliminarily calculating the relation between the levitation amount of a moving blade and a creep deterioration degree and calculating the residual time allowing the creep deterioration degree to reach a torelant limit value from the levitation amount and an operation elapse time. CONSTITUTION:Because the levitation amount (change amount) DELTAa of the mov ing blade of a steam turbine at the implanted part thereof and a creep deteriora tion degree deg.C have extremely clear correspondence relation excellent in reproducibility, this relation is preliminarily calculated experimentally. Because the leviation amount DELTAa increases abruptly when the creep deterioration degree phiC=0.6, the creep deterioration tolerance limit value phiCC of the moving blade can be set to 0.6 and this time is the replacement time of the moving blade. Therefore, when the creep deterioration degree calculated from an already used time tP and a levitation amount DELTAP is set to phi>=CP, the residual life tR of the moving blade can be calculated according to formula tR=phiCC-phiCP.tP/phiCP. |
