The wires of the overhead power line are fixed to the tower by means of insulators and fittings. The insulator used for the insulation of the wire and the tower is not only subjected to the working voltage but also to the overvoltage during operation. At the same time, it must withstand the effects of mechanical force and temperature changes and the surrounding environment, so the insulator must be in good condition. Insulation properties and a certain mechanical strength. Typically, the insulator surface is corrugated. This is because: First, it can increase the leakage distance of the insulator (also known as the creepage distance), and each wave twist can also block the arc; second, when it rains, the sewage flowing down from the insulator will not directly From the upper part of the insulator to the lower part, avoiding the short-circuit accident caused by the formation of the sewage column and blocking the flow of the sewage; the third is that when the contaminated material in the air falls on the insulator, the fouling substance cannot be due to the unevenness of the insulator wave Evenly attached to the insulator improves the anti-staining ability of the insulator to a certain extent. There are many types of insulators for overhead power lines. They can be classified according to the structural type of the insulator, the dielectric medium, the connection method and the bearing capacity.