Abstract:In this paper,the crimped composite insulators are studied. For the problems that is the crimped composite insulators are prone to fatigue failure under the alternating loads on overhead lines; Fatigue failure mechanism of the crimped composite insulators are analyzed from three aspects that is the mandrel substrate material, structural crafts and fatigue fracture, respectively. The conclusion is obtained,that is the capacity of composite insulator withstanding tensile load is much better than withstanding pressure load capacity and the cause of generation stress concentration between the metal fittings and the mandrel. The results show that fatigue failure first occurred in the outer surface of the connection zone and expand from the surface to the entrails. That results provided a new ideas for analyzing fracture cause and referencing to design a new type of anti-fatigue structural of the composite insulators.
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