Several Common Causes of Insulator Faults

insulators and insulating sleeves bear the effects of working voltage and various overvoltage during operation; bear the weight, self weight, ice weight, wind force, system short-circuit electrical force, equipment operation mechanical force, and vibration force of the wire; it also bears the effects of changes in atmospheric conditions and environmental pollution. therefore, its working conditions are harsh.
the general faults and causes are as follows:
1. cracking
the reasons for cracking include: manufacturing defects on the surface and inside of porcelain parts; flashover causes damage to porcelain components due to local overheating; the aging of the applied silicone grease results in leakage current and partial discharge; porcelain surface glaze peeling; cracks on the skirt edge; excessive tightening of hardware causes significant stress on porcelain components; damaged by external forces; damage caused by poor coordination between the porcelain sleeve and internal equipment.
2. creepage marks
the reason is that the insulation surface has formed a pathway due to discharge carbonization, gradually leading to flashover and grounding short circuit accidents.
3. oil leakage
the reason is that severe oil leakage such as cracking, misalignment, and aging of sealing materials will cause insulation breakdown of the casing and may also cause damage to the equipment.
4. corona
the reason is the discharge of the protruding parts on the terminal hardware, along the surface discharge of insulation surface pollution, cracking, and internal defects.
5. terminal overheating
due to poor connection, overheating, discoloration, and shortened insulation life are caused.