Analyze the causes and maintenance methods of mining cable faults

1. The insulation of mining cables has aged and deteriorated
The insulation of power cables is subject to thermal, chemical, and mechanical effects caused by accompanying electrical effects, resulting in physical and chemical changes in the insulation medium and a decrease in the insulation level of the medium. Insulation is damp. The insulation of intermediate joints or terminal heads may become damp due to poor sealing or installation quality of the structure; Defects such as sand holes or cracks left during the manufacturing of cable wrapping lead can also cause the cable to become damp.
2. Mining cable overheating
There are many reasons that can cause cable overheating. The internal cause is the free air gap inside the cable insulation, which causes local heating and carbonization of the insulation. External factors refer to cables installed in areas with high cable density, cable tunnels, etc., cables passing through dry pipes, and cables close to pipelines, which can accelerate insulation damage due to cable overload or poor heat dissipation.

3. Mechanical damage to mining cables
Mainly refers to cable damage caused by external forces. This is mainly due to mechanical effects such as vehicle vibration, which causes cable deformation. Cable deformation leads to excessive bending, damaging the internal insulation or causing air gaps inside the insulation.

4. Corrosion of mining cable sheath
Due to electrolytic or chemical reactions, the lead sheath of cables corrodes. Depending on the nature and degree of corrosion, there are red, yellow, orange, and pale yellow compounds or sponge like pores on the lead sheath.

5. Overvoltage of mining cables causes breakdown
Atmospheric overvoltage and internal overvoltage cause the insulation of the cable to withstand stress exceeding the allowable value, resulting in breakdown. Moreover, analysis of actual faults shows that many outdoor terminal failures are caused by atmospheric overvoltage.
6. Design and manufacturing process issues of intermediate joints and terminal heads for mining cables
When peeling off semiconductors, damage to the internal insulation or impurities such as particles and dust on the insulation surface; Poor sealing of cable heads leads to moisture inside the insulation, causing it to become damp; The cable joint process is not standardized, and the sealing is not standardized, resulting in grounding; The humidity in the production environment is too high, causing the insulation integrity of the production site (cable head) to become damp; The grounding of the cable is incorrect, causing the grounding wire to form a loop or break.