FPSO Underwater Mooring Line Breakage Analysis Based on Broken Wire Material Test

More broken wires was found in No.3 mooring line of "Hai Yang Shi You115"FPSO by the underwater detection. Through the chemical composition analysis, mechanical property testing, fracture analysis, metallographic examination methods, the reason of the broken wire are obtained. The results show that the material of mooring line steel cable mechanical performance is general up to the design spcifications. The broken wire fracture is relatively serious wear and all the sent samples of the present wear trace shape is consistent. It should be the same kind of wear the way by damage and reduced the steel wire tensile strength, lead to fracture.