Self-shattering problem of toughened glass insulator is of great danger to the security of service of transmission lines.Based on several self-shattering cases occurred in China

this paper summarizes and analyzes the self-shattering rule

the influencing factors

and self-shattering mechanism.Besides

the technical measures of decreasing the self-shattering rate are summarized and analyzed.The results show that for glass insulator

a self-shattering peak value exists in the initial stage of service.The residual strength of the residual part is high enough for preventing the insulator string from fracture accident.Natural environment

mechanical load

severe pollution and production technology have influence on the self-shattering.Non-uniform distribution of tensile stress is one of the primary reasons for self-shattering.Technical measures such as secondary hot-and-cold shocking test

inner hydraulic test

homogenous heat treatment

improving glass material quality

and optimizing the toughening process

can be used to decrease the self-shattering rate of toughened glass insulator.