Glass insulator has very good mechanical and electrical properties, its tensile strength, electrical breakdown resistance, vibration fatigue resistance, arc burn resistance and thermal shock resistance are better than porcelain insulator, ceramic insulator it has good insulation performance, climate change resistance, heat resistance and assembly sensitive advantages, is widely used in various voltage levels of the line.
Insulator service life problem
The glass insulator has the characteristics of zero self-explosion. The reason for self-explosion is the impurities and nodules in the glass during the manufacturing process. If the impurities and nodules are dispersed in the inner tension layer, the local self-explosion will occur within a period of time after the product is made. Therefore, the manufacturing unit should store the product for a period of time after manufacturing in order to find the quality hidden dangers in the manufacturing.
If impurities or nodules are dispersed in the outer compact layer, after running on the power line for a period of time, under the action of fierce cold and hot temperature difference and mechanical and electrical load, it is possible to cause the glass insulation to self-explode. In addition, when the glass insulator is wet on the surface, it will partially discharge under the action of power frequency voltage. The long-term heating caused by partial discharge will cause the glass insulation to fall and cause the zero value self-explosion. Therefore, the self-detonation rate of glass insulators operating in dirty areas will be increased.
However, the self-detonation rate of glass insulators is different from the deterioration rate of porcelain insulators and the aging rate of organic composite insulators. The self-detonation rate of glass insulators belongs to early exposure, and with the extension of operating time, the self-detonation rate tends to decline year by year, while the deterioration rate of porcelain insulators belongs to late exposure. With the extension of time, under the action of electromechanical combined load, the deterioration rate will gradually increase. It is generally believed that the aging life of glass insulators and porcelain insulators is about 50 years. The aging life of composite insulators does not exceed 25 years.
