Fatigue analysis damage initiation

Chapter 9 presents various important aspects of oil and gas industry accident data and accident data analysis. Some of the topics covered in this chapter are oil and gas industry accident databases, onshore and offshore oil and gas industry accident data analysis, and offshore oil and gas rigs accident analysis. Chapter 10 is devoted to oil and gas industry equipment reliability and covers topics such as oil and gas pipeline fault tree analysis, corrosion-related failures, optical connector failures, and fatigue damage initiation assessment in oil and gas steel pipes. 

Fig. 4.8 The highest stress from the finite element analysis was at point D and the worst inclusion (porosity) was located at point C. However, the greatest damage from fatigue occurred at point E, arising from the confluence of the stress state and the initial inclusion condition...

Comfortable margins on the primary stresses, very low accumulated creep-fatigue damage, absence of ratcheting, and crack initiation even after application of more than -500 simulated plant load cycles, and extensive experimental validation of finite element results, assures the structural integrity of primary pipe under all the normal and severe loading situations. Analysis shows that the maximum temperature rise of the core outlet sodium temperature (< 0.2 K), due to the leak through critical crack size, cannot be detected. Therefore, LBB demonstration by this mean is not possible. 

---