What are the characteristics and uses of high and low voltage pin insulators
Pin-type insulator [Tianheng Power] is a component used to support or suspend wires and form electrical insulation between the pole and the wire. Pin-type ordinary ceramic insulators, ceramic parts and cast steel are glued together with cement adhesive, and the surface of the ceramic parts is coated with a layer of glaze to improve the insulation performance of the insulator.
(1) High-voltage pin insulators are currently produced in five voltage levels of 6, 10, 15, 20, and 35kV, which are mainly used on linear poles in the middle of the line.
(2) Low-voltage insulators are mainly divided into two types: pin type and butterfly type. The iron foot type can be divided into three types: short foot, long foot and bent foot. The corners, terminals, and branch poles are also called low tea stands.
Porcelain bottle insulators are classified into pin insulators, drum insulators and butterfly insulators according to their shapes. Various types of insulators are also divided into long-column porcelain bottles and short-column porcelain bottles according to the length of their fixing bolts. Wires with a smaller cross-sectional area are generally wired with drum insulators, while wires with a larger cross-sectional area can be wired with pin or butterfly insulators. Among pin, drum and butterfly insulators, butterfly insulator wiring can be applied with the thickest conductor cross section, and drum insulator wiring can be applied with the thinnest conductor cross section.
The tensile strength of the suspension insulator is very high. You can connect several insulators into a string to increase the compressive strength. It can be used in lines with different voltage levels. It can usually be used in the tensile section of the line, or the wire may be suspended. In application, the pin insulator can only support a single independent wire, usually on the base pole to support the wire, because of the question of the withstand voltage limit, it can only be used on the line below 35KV.
Pin-type ordinary ceramic insulators, ceramic parts and cast steel are glued together with cement adhesive, and the surface of the ceramic parts is coated with a layer of glaze to improve the insulation performance of the insulator. The surface of the glue between the cast steel and the porcelain piece is coated with a moisture-proof agent.
The main reason that overhead lines are susceptible to lightning strikes and dirty flashovers is that the pin insulators of the lines are contaminated and absorb moisture in rain, and the insulation level is reduced, resulting in pollution flashovers and breakdowns that cause line faults.
After the pin-type ordinary ceramic insulators are cracked or severely damaged, they can sometimes continue to operate in fine weather; but in light rain or heavy fog, the insulation will drop sharply, causing line failures.
In addition, when a slight crack occurs in the pin-type ordinary ceramic insulator, it is difficult for line patrol personnel to find the defect even if the line patrol is holding the telescope, which leaves a safety hazard to the line and increases the unsafe factors of line operation.
Insulators should have sufficient dielectric strength and mechanical strength. They should not only withstand the effects of working voltage and overvoltage during operation, but also have sufficient resistance to the erosion of chemical impurities, and can adapt to changes in temperature and the influence of the surrounding environment.