What is composite pin type insulator?
Composite pin type insulators is a kind of insulator with silicone rubber insulation housing, and it has a shape like pin. Usually, it consists of weather sheds and sheath housing, fiber glass core, and metal end-fittings.
The materials of top end fittings of composite pin type insulators are hot dip galvanized steel, aluminium steel, ceramic or other. But the bottom end fittings are mostly dip galvanized steel, which bear the cantilevel force (usually < 12.5KN) during operation.
How to choose composite pin type insulator?
According to pollution level of working area
Composite pin type insulators work as supports for conductor of distribution power system (under 69 kV), just like what the porcelain or glass pin type insulators do. In light pollution area we can use porcelain pin type insulator or composite pin type insulator. But in heavy pollution area, the composite pin type insulators must be chosen, because it can prevent the system from flashover by dirty.
Recommended parameters
The following parameters will keep the insulators work stably during operation, and withstand electric tracking and corrosion at bad weather or unnormal working condition. High quality HTV silicone rubber will also maintain the insulators have a better performance of aging.
| electric erosion with a classification | Class 1A 4.5 or 2A 6 |
| withstand a low-intensity-electric arc | 180 seconds |
| tear strength (cohesion) | higher than 8 N/mm |
| hydrophobic features | V0 |
| sitdcone-rubber volume resistivity | higher than 10^10 Ω·m |
| Core materials | ECR fiber glass rod free from boron |
| Aging test | 1000 hours |
Advantage of composite pin type insulators
Most important, after installation of composite pin type insulators, no mantainance needed. That is different from ceramic insulator what need clearing every once in a while. It also can save a lot of cost, if we use composite pin type insulators not ceramic insulators, when we build a new power distribution line or renew an old one.
Classification of composite pin type insulators?
Classified by system voltages, there are 11KV, 15 KV, 25 KV, 33KV … composite pin type insulator.
