热老化对阻燃PVC电缆燃烧性能的影响

The effect of thermal ageing on fire performance of flame retardant PVC cable

采用锥形量热计对不同热老化程度的阻燃PVC电缆的引燃特性和热释放规律进行试验研究。结果表明,电缆试样的引燃时间随热老化程度的增加而延长,老化前期引燃时间增大较快,后期减缓;热释放速率的初始峰值随热老化程度的增加呈下降趋势;火灾性能指数随老化时间的延长总体呈下降的趋势。故与新投入使用的电缆相比,老化电缆的引燃危险和热危险相对减小。

The impact of different degree of thermal aging on the ignition character and heat release rule of flame retardant PVC cable is researched by means of cone calorimeter. Results indicate that ignition time basically increases with aging time, and it increases fast at the earlier stage of thermal aging, and slower later. The peak of heat release rate decreases with aging time. The fire performance index （FPI） of the cables decreases with aging time. So compared to the cables newly put into operation, the aging ones have smaller hazard of ignition.