According to the definition of “Basic Terminology of Power Engineering” GB/T50297, an insulator is a device used to support and insulate a conductor. Insulators The main insulators made of porcelain, glass or organic materials are called porcelain insulators, glass insulators or organic material insulators.

The main function of the insulator is to achieve electrical insulation and mechanical fixing, for which various electrical and mechanical properties are specified.

a. Electrical performance requirements:

Under the specified operating voltage, operating overvoltage and lightning overvoltage, no breakdown or flashover along the surface occurs.

b. Mechanical performance requirements:

No damage or damage is caused by the specified long-term and short-term mechanical loads.

Installation method

According to different installation methods, it can be divided into suspension insulators and post insulators.

Suspension insulator

It is widely used in the insulation and mechanical fixing of high-voltage overhead transmission lines and soft and busbars of power transmission and distribution. Among the suspension insulators, they can be further divided into disc suspension insulators and rod suspension insulators. Disc suspension insulators are the most widely used insulators for transmission lines.

Post insulator

Mainly used for insulation and mechanical fixing of busbars and electrical equipment in distribution lines, power plants and substations. In addition, post insulators are often used as part of electrical equipment such as disconnectors and circuit breakers. Among the post insulators, it can be further divided into a pin post insulator and a bar post insulator. Pin-type post insulators are mostly used in low-voltage distribution lines and communication lines, and rod-shaped post insulators are mostly used in high-voltage substations.