Commonly used power fittings and classification of overhead transmission lines

Metal accessories such as iron, aluminum or aluminum alloy widely used in power lines, equipment and conductors, conductors and wires in power distribution devices of step-up substations and step-down substations, connections of transmission line wires themselves, and insulators are connected in series, Metal (iron, aluminum or aluminum alloy) accessories used for the protection of wires and insulators themselves are called power fittings. Power fittings are mainly metal accessories that connect and combine various devices in the power system to transmit mechanical loads, electrical loads, and some protection. Among them, the power fittings used for overhead transmission lines are called line fittings. Line fittings are used for connection between wires, between insulators, between insulators and towers, and between insulators and wires on overhead transmission lines. It must have sufficient mechanical strength and flexibility in assembly and operation.

There are many types of power transmission line fittings with different uses, such as various clamps for installing wires, various hanging rings that form insulator strings, various crimping tubes and repairing tubes for connecting wires, and various types of split wires. Spacer rods, etc., in addition to various types of pull wire fittings used for poles, and the size of the protective conductors, must be matched with each other. According to the main performance and purpose of the fittings, the line fittings can be roughly divided into suspension clamps, strain clamps, connection fittings, protection fittings, connection fittings and pull wire fittings, etc.