DNV DNV-RP-E104 PDF

This recommended practice provides a consolidated framework for fatigue assessment of subsea and surface well systems during all stages of operation. The described methods cover the following areas:

— computation of both mean and cyclic loads experienced by the wellhead/casing system for each set of conditions

— relationship between cyclic loads and cyclic stresses, such as load-to-stress curves and stress amplification/concentration factors for each location of interest

— damage model, such as S-N approach, initiation life method, and fracture mechanics used to estimate fatigue damage at each location of interest.