TY - GEN
T1 - Corrosion fatigue behavior of mooring chain steel in seawater
AU - Arredondo, Alberto
AU - Fernández, Jonathan
AU - Silveira, Elena
AU - Arana, Josí Lu s.
N1 - Publisher Copyright:
© 2016 by ASME.
PY - 2016
Y1 - 2016
N2 - With a majority of the reported chain failures related to fatigue, this phenomenon is one of the main topics to be studied as part of Mooring Integrity Management. Present fatigue design is mainly based on fatigue curves for chains under tension-tension loads in seawater. However, the applicability of these curves for different loading modes and specific environments remains unclear. This paper studies the fatigue behavior of the material used on chains as it builds the baseline for the performance of these mooring components. It includes uniaxial fatigue tests that were undertaken on R4 and R5 steel grades obtained from actual chains after all their manufacturing steps. Samples were not only tested in air and in synthetic seawater but different corrosion related parameters were also studied: frequency, temperature and cathodic protection. From the results of these tests, separated SN curves were obtained. Subsequently, these curves were analyzed and compared against present recommended design curves for material. Fractographic examination was undertaken to assess the effect of corrosion and cathodic protection and comparison between material and component response was also addressed. Results showed the strong synergy between corrosion and fatigue. Also, the improvement from fatigue design curves to actual response of the materials was quantified.
AB - With a majority of the reported chain failures related to fatigue, this phenomenon is one of the main topics to be studied as part of Mooring Integrity Management. Present fatigue design is mainly based on fatigue curves for chains under tension-tension loads in seawater. However, the applicability of these curves for different loading modes and specific environments remains unclear. This paper studies the fatigue behavior of the material used on chains as it builds the baseline for the performance of these mooring components. It includes uniaxial fatigue tests that were undertaken on R4 and R5 steel grades obtained from actual chains after all their manufacturing steps. Samples were not only tested in air and in synthetic seawater but different corrosion related parameters were also studied: frequency, temperature and cathodic protection. From the results of these tests, separated SN curves were obtained. Subsequently, these curves were analyzed and compared against present recommended design curves for material. Fractographic examination was undertaken to assess the effect of corrosion and cathodic protection and comparison between material and component response was also addressed. Results showed the strong synergy between corrosion and fatigue. Also, the improvement from fatigue design curves to actual response of the materials was quantified.
UR - http://www.scopus.com/inward/record.url?scp=84996503659&partnerID=8YFLogxK
U2 - 10.1115/OMAE2016-54426
DO - 10.1115/OMAE2016-54426
M3 - Conference contribution
AN - SCOPUS:84996503659
T3 - Proceedings of the International Conference on Offshore Mechanics and Arctic Engineering - OMAE
BT - Offshore Technology; Offshore Geotechnics
PB - American Society of Mechanical Engineers (ASME)
T2 - ASME 2016 35th International Conference on Ocean, Offshore and Arctic Engineering, OMAE 2016
Y2 - 19 June 2016 through 24 June 2016
ER -