IEEE Task Force Report: Brittle Fracture in Nonceramic Insulators

NGK-Locke, Inc.; K-Line Insulators USA, Inc.; Hubbell Power Systems; Consultant; Sediver; Arizona State University; STRI; Maclean Power Systems; American Electric Power; Glasforms, Inc.; Alabama Power; Bonneville Power Administration;
IEEE Power Engineering Review 06/2002; 22(5):71-71. DOI: 10.1109/MPER.2002.4312228
Source: IEEE Xplore

ABSTRACT A description of the composite insulator brittle fracture phenomenon suitable to allow correct diagnosis of a failure is provided. The paper reports on the number of brittle fractures that have occurred around the world and contains specific empirical data surrounding composite insulator brittle fractures in the United States. It also includes several case studies of in service failures to inform the reader of the diversity of initiating causes. The current state of knowledge on the brittle fracture mechanism is presented. Based on what was learned during the study, possible actions that can be taken by manufacturers and users to reduce frequency of occurrence are suggested.

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