Transmission Line is an important part of the line in the long run, the floating dust would be dirty, wind, snow, fog, heavy rain, high temperature, humidity, temperature changes, lightning, birds, the interference of external factors such as damage and impact, will be struck by lightning over-voltage, the system operating voltage, leakage current due to dirty short-term impact on the insulator will withstand the impact of current and arc current frequency transient impact; detailed grasp the line running, in-depth analysis of the common faults, scientific and effective precautionary measures taken to actively use the state maintenance, rapid elimination lack comprehensively enhance the line the whole life-cycle safety in working conditions and operational capabilities.