Insulators used on transmission lines can be divided into two categories: disc suspension and rod suspension according to their structural forms, while according to the classification of dielectric materials, there are three types of insulators: porcelain, glass and organic synthetic insulators
The electric porcelain of disc-shaped suspension porcelain insulator is a porcelain piece made of quartz sand, clay, feldspar and other raw materials through ball milling, pulping, mud refining, forming, glazing and sintering. It is bonded with steel cap and steel foot by high-grade cement to form cap foot disc-shaped suspension porcelain insulator. The steel cap and steel foot bear mechanical tension, the porcelain parts mainly bear pressure, and the neck of the porcelain parts is thin, which is also the area where the electric field intensity is concentrated. When there are micro pores and other defects in the neck of porcelain parts, or cracks appear in operation, it is possible to break down the porcelain parts and produce zero value insulators. Therefore, this kind of insulator is a breakdown type insulator. The glass parts, steel caps and steel feet of tempered glass insulators are installed with high-grade cement to form cap foot type disk suspension tempered glass insulators. Its structure and shape are very close to that of porcelain insulator. When the glass parts in operation are deteriorated due to the comprehensive action of long-term mechanical force and electric field, the umbrella disc of tempered glass body will be broken, that is, "self explosion". The most remarkable feature of toughened glass insulator is that it will self explode when there are inferior insulators in toughened glass insulator, which eliminates the complicated procedure that insulators must be tested one by one. The outer end of the insulator is made of a composite silicon rubber core rod, which is formed by an epoxy resin, and the outer end of the insulator is connected with the umbrella core rod. The core rod is formed by an epoxy resin, and the outer end of the insulator is formed into a composite umbrella. The connection modes of mandrel and end fittings mainly include external wedge type, internal wedge type, internal and external wedge combined type, mandrel rib glue type and crimping type. Due to its relatively simple manufacturing equipment and manufacturing process, the quality of composite insulator products is relatively light, and all are easy to operate, which is very favored by the power department.
Therefore, glass insulator, ceramic insulator and composite insulator have their own advantages and disadvantages. In the installation process, it also depends on the design needs of specific lines to see which is more suitable
1. The main varieties of porcelain insulator products include: ordinary disc suspension porcelain insulator, pollution resistant disc suspension porcelain insulator, straw hat disc suspension porcelain insulator, ground wire disc suspension porcelain insulator, post porcelain insulator, pin porcelain insulator, porcelain cross arm insulator, post porcelain insulator, butterfly porcelain insulator, tension porcelain insulator and tram porcelain insulator;
2. The main varieties of glass insulator products include: standard disc suspension glass insulator, pollution resistant disc suspension glass insulator, aerodynamic disc suspension glass insulator and ground wire glass insulator;
3. The main varieties of composite insulator products include: composite suspension insulator, composite post insulator, composite pin insulator, composite cross arm insulator, composite lightning protection insulator and disc suspension porcelain composite insulator;
