Patent ID: 8306759

Claim:
An apparatus for calculating a fatigue usage factor, comprising: a transient state input unit to input information related to a transient state created during operation of the mechanical device; a characteristic fatigue usage factor calculating unit to calculate a characteristic fatigue usage factor based on an operation-transient state; a characteristic fatigue usage factor curve generation unit to generate a characteristic fatigue usage factor curve using the characteristic fatigue usage factor calculated by the characteristic fatigue usage factor calculating unit; a fatigue usage factor calculating unit to calculate a fatigue usage factor based on the operation-transient state; a cumulative fatigue usage factor calculating unit to calculate a cumulative fatigue usage factor based on the operation-transient state using the fatigue usage factor calculated by the fatigue usage factor calculating unit; and a cumulative fatigue usage factor output unit to output the cumulative fatigue usage factor calculated by the cumulative fatigue usage factor calculating unit to analyze an effect of a transient state created during operation of a mechanical device on a fatigue index in a material of a mechanical device, wherein a value of the characteristic fatigue usage factor which corresponds to the characteristic fatigue usage factor is obtained using the generated characteristic fatigue usage factor curve, and the operation-transient based fatigue usage factor is calculated by multiplying a design-transient based fatigue usage factor by the characteristic fatigue usage factor.