Three factors that affect the reliability of the insulator

    Manufacturing level is guaranteed. In other countries, high-quality products have formed a considerable economies of scale and high technology with advanced automated production lines. The whole of Western Europe and the former Soviet Union, glass insulators market share as high as 90%; the entire North American use of composite insulators for the highest in the world, accounting for 25% to 30% of the total local market insulator; in Japan, the domination of porcelain insulators. In China, fortunately made glass insulators through the introduction of technology and self-development, already have these production conditions. For ceramic and composite insulators, in addition to individual joint venture, said the manufacturing level in China has not yet reached. Visible, selection of the products also depends on the level of product manufacturing and a comprehensive understanding of the product performance and use of the environment.

    Product mix and stain resistance are key. Glass insulators using cylinder head structure, bearing assembly by force. Compared with domestic traditional porcelain insulators consistent system for decades conical head structure, small size, light weight, high strength and excellent electrical performance characteristics. Since the linear expansion coefficient of the glass is much larger than the porcelain, dimensions smaller than the composite insulation materials, and easy connections with metal accessories and cement, thus the force component material well-matched. In all weather conditions, unlike porcelain insulators and composite insulators as prone to dangerous stress caused by aging. And composite insulators difficult to solve structural quality composite interface. But composite insulators have excellent stain resistance, and usually do not need cleaning. This greatly reduces the cost of line maintenance, in this connection, composite insulators and broad development prospects. The dielectric constant of glass is larger, and therefore single dry glass insulator flashover voltage than porcelain insulators low, but there is a large main capacitor to improve voltage distribution surface, and make the porcelain insulator string flashover voltage equivalent. Coupled with glass insulator leakage ratio from large, less surface aggregates, strong ability to resist thermal stress caused by the contamination, and thus less susceptible to flashover accident. East China Power Grid decades flashover practice repeatedly proven superior stain resistance glass insulator porcelain insulators.

    Material is the foundation. Glass and porcelain are the property of aluminum silicates, porcelain is a three-phase (crystalline phase, glass phase and gas phase) coexist not homogeneous body, while the glass is liquid and glassy mutually reversible homogeneous body. "Homogeneity" is an important factor affecting the dielectric strength of the insulation material. The mechanical strength of brittle materials and thermal stability, does not depend on the mechanical properties of the materials, but on the state of internal defects and surface material to a great extent. This is compared to annealed glass, tempered glass and porcelain, glazed porcelain strength porcelain glazed much less reason. In addition, the "hot steel" technology to give glass surface of glass up to 100 ~ 250MPa a permanent prestressing. This is the "glass" strength steel, high thermal stability, compared with porcelain difficult to aging and long life of truth. Difficulties for composite insulators of organic material is the solution to aging in outdoor conditions, the mandrel brittle fracture and creep. Visible, glass ceramics have both much higher than the mechanical, dielectric strength, and the more organic material has excellent anti-aging properties, for the reliable operation of insulators laid a good foundation.