About some important items of composite insulators design

Contemporary composite insulators differ in manufacturing process largely related to their design. Composite insulators in service are exposed to pollution, creepage currents, corona discharges and weathering. This can result in ageing effects which change the surface properties of polymer housing. Apart from the importance of the recovery of hydrophobicity of the silicone housing material and the diffusion of low molecular weight polymers to the surface, the general design and the particular design items play weighty role in reliability of products and exclusion of any mechanical and electrical failures during service, Some effects of different design items on the field conditions near the high voltage flange of composite insulators are revealed.