PREDICTING THE LIFE OF HIGH-TEMPERATURE STRUCTURAL COMPONENTS IN POWER-PLANTS

The concept of time-dependent fracture mechanics has been used to develop the quantitative life-prediction methodology and inspection criteria for high-temperature structural components. As an example, the methodology was applied to steam pipes. Leak-before-break analyses were utilized to determine the flaw inspection criteria of steam pipes. Both static and cyclic loading conditions were included in the life-prediction analyses. Increasing the frequency of shut-downs was found to decrease the remaining life. The effects of operating pressures and temperatures and material properties on the life of steam pipes were quantified.