اثرات پیری انعطاف پذیر مواد بر زمان احتراق و میزان انتشار گرما در کابل های عقب انداز

The effects of insulating material ageing on the fire performance of flame retardant cables were investigated experimentally by cone calorimeter in the present study. The ageing time and ageing type of the insulating material were concerned, and the fire hazard of cables was represented by the ignition time and the heat release rate (HRR). The results show that both the ignition time and the peak of HRR increase with the ageing time first and then decrease slightly for the flame retardant control cables with polyvinyl chloride insulated and polyvinyl chloride sheathed (ZR-KVV). For the flame retardant control cables with crosslinked polyethylene insulated and polyvinyl chloride sheathed (ZR-KYJV), the ignition time increase and the peak of HRR decrease with the ageing time. The effects of ageing type of insulting material on fire hazard of cables were investigated with the ZR-KVV cables. The ignition time and the HRR of the thermal aged cables were higher than those of the xenon arc aged cables, the ozone aged cables and the hydrothermal aged cables. The results of fire hazard assessment of aged flame retardant cables according to the ignition time might be opposite to those derived from the HRR of cable fires, which should be paid attentions in cable fire safety evaluations.