| Cable fire is one of the most serious disasters in the electric power system, which not only causes direct economic losses, but also may cause chain safety accidents. In order to quickly fire-resistant transformation of existing ca-bles, this paper innovatively prepares four different types of coated intumescent fire-resistant materials, which can be easily wrapped and bonded to achieve fire resistance modification of ordinary cables, increasing their fire re-sistance time by 12 times compared to unmodified cables. The flame retardancy, insulation properties and ageing resistance of four types of coated wrapping materials (TF1-1, TF1-2, TF1-3, TF1-4) are comparatively investi-gated by smoke density test, oxygen index test, insulation property analysis, cone calorimeter test, residual carbon analysis, ageing performance and thermal stability test. Among them, TF1-2 has a small smoke production, a low peak smoke release value of 0.016 m2/s, a peak heat release rate of 47.0 kW/m2, a FGI value of only 0.59 kW/m2s, and a slow fire spreading rate. In the fire resistance test, due to the TF1-2 thermal protection, the average temper-ature inside the cable is only 355 °C with a fire resistance time of 113.3 min when the external flame is as high as 992 °C。 |
