Quantitative relationship between the fatigue stress, S, and the number of cycles, N, corresponding to a specific probability of failure for a detail, derived from test data.
Source: API Technical Report 17TR7, Verification and Validation of Subsea Connectors, First Edition, April 2017. Global Standards
A plot of stress range (S) against the number of cycles (N) to failure obtained by cycling specimens to failure.
Source: API Standard 2RD, Dynamic Risers for Floating Production Systems, Second Edition, September 2013. Global Standards
Graphical presentation of the dependence of fatigue life, N, on fatigue strength, S. NOTE It is also known as the Wöhler curve.
Source: API RP 17G, Recommended Practice for Completion/Workover Risers, Second Edition, July 2006 (Reaffirmed April 2011). Global Standards