The cause was a material-component failure due to hydrogen embrittlement. The mechanism is known as SSC (sulfide Stress Cracking). SSC is basically a hydrogen embrittlement phenomenon, in which atomic hydrogen penetrates in the steel cracking it. It is a mechanism susceptible to occur when 3 circumstances take place simultaneously: a susceptible material, a brittle atmosphere (H2S) and a sufficient maintained level of stresses. It is a mechanism that can happen under mechanical loads of remarkably lower magnitudes than the elastic limit of the material, being able to be sufficient the own residual stresses of manufacturing or assembly. Susceptibility to hydrogen embrittlement of steels is as much greater as it is its mechanical resistance or hardness, a reference value of 26 HRC being used for martensitic stainless steels with quenching and tempering thermal treatment (In this case, bolts had a hardness 48 HRC).