Self-priming silicone elastomeric coatings for high voltage insulator bodies

In electric power transmission, there is a trend towards higher operating voltages and more severe service conditions for outdoor insulators. Historically, higher voltages have called for bigger, heavier insulators, with larger support structures to carry the increased weight. Now, for economic reasons, there is an urgent need to reduce weight and size in insulators and support structures. Considerable research and development effort is being spent to synthesize and evaluate stronger, lighter-weight insulating materials. Test methods used to screen and evaluate new insulating materials have been based mainly on the outdoor, high voltage experience gained with porcelain insulators. These test methods are attempts to re-create-on a laboratory, accelerated scale-the actual problems which occur on porcelain in outdoor service conditions. These outdoor service problems have steadily increased during recent years, caused by the combination of higher operating voltages and increased industrial pollution.