The trend currently observed in the oil exploration industry is prodominantly geared towards the development of low-cost repair techniques. An example of this trend is the wet welding process used used in underwater repairs, at considerably lower costs that those incurred when using the traditional dry hyperbaric welding system. The objective of this work is to analyze and outline the main fatigue characteristics of wet welding processes, by comparing the behaviour of two different materials: the addition metal resulting from the wet welding process, and the behaviour of the base or parent metal. This study will allow us to obtain a whole set of properties related to fatigue, including data on low-cycle fatigue and fracture mechanics. These properties were duly analyzed and compared with data found in literature available on this matter. A wide and in-depth discussion is carried out covering the study of several models developed previlously, wich have establisehd the ratio existing between oligocyclic fatigue and the crack propagation rate. Furthermore, on the basis of studies carried out, some modifications are being proposed to adjust these models to the requirements of experimental data obtained.