Insulator English name: insulator
Definition: A device that is capable of withstanding voltage and mechanical stresses between conductors of different potentials or between conductors and ground potential components. Insulators are a special type of insulation control that can play an important role in overhead transmission lines. In the early years, insulators were mostly used in utility poles. Later, one end of the high-voltage high-voltage wire connection tower was hung with a large number of disk-shaped insulators. In order to increase the creepage distance, it is usually made of glass or ceramic, which is called an insulator. Insulators play two fundamental roles in overhead transmission lines, namely supporting the conductors and preventing current from returning to the ground. These two functions must be ensured. The insulators should not fail due to various electromechanical stresses caused by changes in environmental and electrical load conditions. Otherwise, the insulator will not have a major effect, which will damage the use and operating life of the entire line.
Historical origin and overview of insulators In the early years, insulators were mostly used in utility poles. Slowly developed at the end of high-voltage high-voltage wire connection towers, many disk-shaped insulators were hung. It is used to increase the creepage distance, usually made of glass or ceramic. It is called an insulator. Insulators play two fundamental roles in overhead transmission lines, namely supporting the conductors and preventing current from returning to the ground. These two functions must be ensured. The insulators should not fail due to various electromechanical stresses caused by changes in environmental and electrical load conditions. Otherwise, the insulator will not have a major effect, which will damage the use and operating life of the entire line.
Transmission and distribution line tempered glass insulator product structure transmission and distribution line tempered glass insulator The main material of the general insulator is iron cap, tempered glass or ceramic and steel feet, and cement glue is integrated into one.
Insulators A high-voltage wire connection tower has a plurality of disk-shaped insulators attached to one end. This is to increase the creepage distance. It is usually made of glass or ceramic and is called an insulator. In order to prevent dust and other contamination from adhering on the surface of the insulator, the formation of the passage is broken by the voltage across the insulator, that is, creepage. Therefore, increasing the surface distance, that is, the creepage distance, the distance discharged along the insulation surface, that is, the leakage distance is called the creepage distance. Surface distance / system maximum voltage. Depending on the degree of contamination, heavy dirt areas generally use a creepage distance of 31 mm / kV.
Insulator classification
1. Insulators are usually classified into a breakable type and a non-breakable type.
2. According to the structure, it can be divided into column (pillar) insulators, suspension insulators, anti-fouling insulators and bushing insulators.
3. According to the application, it is divided into line insulators and power stations and electrical insulators. Among them, the puncturable insulator used for the circuit has a pin type, a butterfly shape, a disc type suspension type, and the non-breakable type has a cross arm and a rod type suspension type. The puncturable insulators for power stations and electrical appliances have pin-type struts, hollow struts and sleeves, and non-breakable type of rod-shaped struts and container porcelain sleeves.
4. Insulators used in overhead lines, commonly used are pin insulators, butterfly insulators, suspension insulators, porcelain crossarms, rod insulators and tension insulators.
5. Commonly used insulators are: ceramic insulators, fiberglass insulators, composite insulators, and semiconductor insulators.
Insulator maintenance and management
Insulator cleaning
In wet weather conditions, dirty insulators are prone to flashover discharge, so they must be cleaned to restore the original insulation level. The general area is cleaned once a year, and the dirty area is cleaned twice a year (before the fog season).
1. Power-off cleaning: The power-off cleaning is to wipe the worker with a rag after the line is cut off. If it is not cleaned, it can be wiped with a damp cloth or with a detergent. If it is not cleaned, replace the insulator or replace the composite insulator.
2, no power off cleaning: generally use a brush or tied with cotton yarn insulation rod, wipe the insulator on the running line. The electrical performance and effective length of the insulating rod used, and the distance between the person and the live part shall comply with the corresponding voltage level, and must be monitored by a person.
3, charged water rinse: big water and small water and two methods. The flushing water, the effective length of the operating rod, and the distance between the person and the charging department must meet the requirements of the industry regulations.
Insulator preventive test
1, infrared temperature measurement
2, zero-value insulator detection
3, contamination level test