Porcelain insulation for EHV equipment and transmission lines

Insulators used on high voltage systems are not particularly fragile; but they are, undeniably, brittle. Reasonable familiarity with flaw and fracture theory is prerequisite to an understanding of a brittle material. Consider, for example, the following list which the authors have selected from their subjects and projects of the past year: Analysis of insulator failures, in service or from handling. Gunshot and power arc resistance of suspension insulators. Residual strength of damaged insulators. A method of measuring the “toughness” of ceramic materials. Hydraulic test for suspension insulator shells. Statistical specifications for insulators.^{1, 2}