Mechanical properties investigation of the composite insulators in service

This paper reports the mechanical properties of 76 composite insulators of early stage that are in service for Guangdong power grid and Northeast power grid. Combining the test results, breaking forms and mechanical strength of the composite insulators with three link fittings were explained, and the mechanical properties were evaluated. There are different degrees of cracks in the core surface. The main destruction forms are different for the ends link forms of the fittings are different. The main destruction forms of inner wedge type are the ball head break, the core break and the core damage, and the proportion is 44%, 44% and 12%, respectively. For the outer wedge type, the main destruction forms are the core break, the ball head break, the core pulled off and the core damage, and the…