Patent ID: 7552647

Claim:
A turbine blade fatigue life evaluating method, comprising: measuring an initial length of a turbine blade in an initial state in which a creep elongation strain is zero; marking the initial length on the turbine blade; marking wall temperature of the turbine blade which is measured when the initial-dimension is measured, onto the turbine blade; measuring a post-operation length of the turbine blade after being operated for a predetermined time; estimating a creep elongation strain in a longitudinal direction of the turbine blade based on the initial length and the post-operation length; and evaluating that the turbine blade is within its fatigue life if the creep elongation strain is less than 0.5% of the initial length, or evaluating that the turbine blade exceeds its fatigue life if the creep elongation strain is equal to or more than 0.5% of the initial length.