(in lingua inglese)
The failure analysis was thus not about identifying bulk steel failure, because we did not have the continuous bulk steel in the tube, where the final failure happened. Because the finding of these cracks identified the cause of the failure, it was not relevant or necessary to investigate fracture surface of steel, viz. the fracture surface of these pre-existing cracks. The existence of them was the cause of failure. This investigation thus was not a usual metal failure analysis, which tends to be around discussing mechanisms of failure such as brittle and much localized fracture, potential embrittlement caused by galvanisation, ductile rupture, fatigue including low cycle fatigue that could have been induced by corrosion pits so enhancing low cycle fatigue damaging.