31 Fatigue Crack Growth, Fatigue, and Stress Corrosion Crack Growth: Section XI Evaluation

In Chapter 31, Warren H. Bamford discusses the Code evaluation of fatigue crack growth, consistent with the evaluation methods of Section XI. Fatigue has often been described as the most common cause of failure in engineering structures, and designers of pressure vessels and piping have incorporated fatigue considerations since the first Edition of Section III in 1963. The development of this technology and its application in Section III is discussed in Chapter 39; its application in Section XI is discussed in Chapter 31. With the advancement of the state of the art has come the capability for allowing the presence of a crack, for predicting crack growth, and for calculating the crack size that could lead to failure. This capability has been a key aspect of the Section XI flaw evaluation procedures since the 1974 edition of Section XI; it is discussed thoroughly in Chapter 31.

Warren discusses the background of the criteria for fatigue crack growth analyses and crack growth evaluation methods. Drawing upon his considerable experience in formulating these criteria and his professional expertise in these analyses and evaluations, Warren provides commentary on the calculation of crack shape changes; calculation of elastic-plastic crack growth with the aid of crack growth rate reference curves for ferritic and austenitic steels in air environments; and crack growth rate curves for ferritic and austenitic steels in water environments. He also discusses operating plant fatigue assessment with the aid of Appendix L of Section XI. Also included are discussions pertaining to Appendix A, fatigue evaluation, and flaw tolerance evaluation. He provides extensive bibliographical notes and references.