Fracture Analysis of the Marine Towlines

Two marine towlines fractured one after another in two days. The fracture reason was analyzed by means of chemical compositions analysis, metallographic examination, micro-hardness test and fracture analysis. The results show that the two times of fracture both occurred under cycle and over-loading. The fracture process was that the core lines of the towline fractured firstly and then the external lines fractured, so the whole towlines fractured in a short time.