The main cause of wire and cable burst into flames

The main cause of wire and cable fire power cable insulation is usually made of paper, oil, hemp, various combustible material such as rubber, plastic, asphalt, therefore, the cable has the possibility of fire explosion, and the cause of wire and cable fire explosion mainly has the following 6 points: 1, insulation damage caused by short circuit fault, the protection of the power cable lead leather was damaged during installation or in the operation of the cable insulation by mechanical damage, cause and cable or lead insulation breakdown between the skin and the arc made of insulating material and fire broke out on cable covering material. 2, cable run overload for a long time, long time overload operation, the operating temperature of the cable insulation materials more than the allowable temperature, normal fever has dried up cable insulation aging, this kind of phenomenon of insulation aging dry, usually occurs in the cable on the road. Due to cable insulation aging dry insulation material loss or lower insulating performance and mechanical performance, and therefore easy to burning occurrence breakdown, and even the whole length along the cable fire broke out on several at the same time. 3, oil immersion cable in elevation difference with the drip, leak, when the oil immersion cable laying elevation, cable drip oil phenomena may occur. As a result of the running stream cable upper dry due to the loss of oil, the part of the thermal resistance of the cable, make paper insulated coking and breakdown in advance. In addition, because the upper oil drip down, in the upper cable head room and produce negative pressure, make the cable easy to absorb moisture and make the end be affected with damp be affected with damp. Lower part of the cable due to the accumulation of oil to produce a lot of static pressure, prompting cable head leak. Cable be affected with damp be affected with damp and oil increases the failure probability of the fire. 4, the middle connector box insulation breakdown: cable joint box because of the pressure in the middle of the joint is not tight, improper material selection, welding not firm or joint operation of the joint oxidation, fever, plastic flow; When doing cable intermediate joint, perfusion in the middle connector box inside the insulation of the agent is not in conformity with the quality requirements, perfusion insulation agent, box of memory with porosity and poor cable box sealing, damage and leakage into the moisture, the above factors can cause insulation breakdown, form a short circuit, cable burst into flames. 5, cable head burn: due to the cable head surface dirt deposition of be affected with damp be affected with damp, cable head porcelain sleeve break and lead phase spacing is too small, lead to fire flashover, cause cable head surface insulation insulation inlets and combustion. 6 lead to cable fire, the fire and heat source, such as oil system of fire spread, the spread of the oil circuit breaker fire explosion in coal pulverizing system of boiler or pulverized coal spontaneous combustion of a coal conveying system, high temperature steam pipe of baking, acid and alkali chemical corrosion, electric welding sparks and other fire, can make the cable fire.