In recent years, with the widespread use of electricity, cable has also entered our lives. However, cable accidents are also common, especially the frequent occurrence of accidents in the cable, which poses a great threat to our personal safety. So what exactly is the cause of the explosion of wire and cable? How should we avoid the occurrence of this situation? The following analysis is for you.
1. insulation damage caused by a short circuit
Wire and cable protection layer in the process of laying, damage, or cable insulation in the course of operation by mechanical damage. Caused by the cable phase or protective layer breakdown, the resulting arc makes the insulation material and the cable outer protective layer material burning fire.
2. Long-term overload operation of the cable
In long-term overload operation, the operating temperature of the cable insulation material exceeds the normal heating temperature allowed, accelerating the aging of the cable insulation. This insulation aging phenomenon usually occurs in the entire cable line. Due to the aging of cable insulation, the insulation material loses or reduces the insulation performance and mechanical properties. Therefore, it is easy to fire and combustion, or even multiple combustion and fire, along the entire length of the cable.
3. Intermediate joint box insulation breakdown
The middle joint of the cable joint box is not tightly crimped, poorly welded, or improperly selected joint materials, and the joint is oxidized, heated, and glue flowing during operation. When making the cable intermediate joint, the quality of the insulating agent poured into the intermediate joint box does not meet the requirements, and when filling the insulating agent, there are air holes in the box and poor sealing of the cable box, damage, and leakage into the moisture. All of the above factors can cause an insulation breakdown, the formation of a short circuit, causing the cable explosion and fire.
4. Cable head burning
As the cable head surface is contaminated with moisture, the cable head porcelain jacket rupture, and the lead-in line phase distance is too small, causing flashover fire. Eventually, cause the cable head surface insulation and lead wire insulation layer burn.
5. External fire and heat sources caused by the cable fire
For example, the spread of oil system fires, the spread of oil circuit breaker explosion fires, boiler pulverizing system or coal transmission system of pulverized coal spontaneous combustion, high-temperature steam pipeline baking, acid, and alkali chemical corrosion, welding sparks and other fires, can make the cable fire.
Therefore, we must often carry out regular line safety inspections. Wires, electrical equipment, etc. at least once a year to have a professional comprehensive, and thorough inspection. In particular, the joint parts of the use of older lines found that the wire aging, broken, poor insulation and other unsafe conditions, to repair and replace in a timely manner, in order to ensure the safety of electricity. Finally, remind everyone that the purchase of wire and cable must be recognized as a regular manufacturer, check the quality, do not go to buy some non-qualified wire because the price is cheap.