Causes of power cable fire_Anhui Honglin Instrument Cable Co., Ltd.

Causes of power cable fire

Author：hlyb Add Time：2016-03-09 16:06:17

Power cables are used in major domestic projects. The insulation layer of power cables is composed of paper, oil, hemp, rubber, plastic, asphalt and other combustible substances. However, power cables may catch fire and explode during use.

The reasons are as follows:

1. Cable overload operation for a long time. For long-term overload operation, the operating temperature of cable insulation material exceeds the high allowable temperature of normal heating, so that the insulation of cable is aged and dry. This phenomenon of insulation aging and dry usually occurs on the whole cable line. Due to the aging and drying of the cable insulation, the insulating material loses or reduces the insulation and mechanical properties, so it is prone to breakdown, fire and combustion, and even combustion and fire at many places along the whole length of the cable.

2. Short circuit fault caused by insulation damage. The protective lead sheet of power cable is damaged during laying or the cable insulation is mechanically damaged during operation, resulting in insulation breakdown between cable phases or between lead sheets, and the generated arc will burn the insulating materials and the materials of the outer protective layer of the cable.

3. Cable head burns. Due to the moisture and dirt on the surface of the cable head, the porcelain sleeve of the cable head is broken and the distance between outgoing lines is too small, resulting in flashover and fire, resulting in the insulation combustion of the surface layer of the cable head and the insulation of the outgoing line.

4. Insulation breakdown of intermediate joint box. The middle joint of the cable joint box is oxidized, heated and glue flowing during operation due to loose crimping, loose welding or improper selection of joint materials; When making the cable intermediate joint, the quality of the insulating agent poured into the intermediate joint box does not meet the requirements. When pouring the insulating agent, there are pores in the box and the cable box leaks moisture due to poor sealing and damage. The above factors can cause insulation breakdown, form short circuit and cause cable explosion and fire.

5. Cable fire caused by external fire source and heat source. For example, the spread of fire in the oil system, the explosion of oil circuit breaker, the spontaneous combustion of pulverized coal in the boiler pulverizing system or coal conveying system, the baking of high-temperature steam pipeline, the chemical corrosion of acid and alkali, welding sparks and other kindling can cause fire in the cable.

Browse：

On A：Production and technical standards of wires and cables

Next：No

technical support

Causes of power cable fire