典型阻燃及耐火电缆的水平延燃特性试验研究

Experimental Study on Horizontal Flame Spread Characteristic of Typical Flame Retardant Cable and Fire Resistant Cable

参照美国消防协会标准NFPA 262《电线电缆燃烧和发烟特性的标准测试方法》设计构造电缆水平燃烧试验装置,对交联聚乙烯护套聚氯乙烯绝缘电缆(YJV)和阻燃交联聚乙烯护套聚氯乙烯绝缘电缆(ZR-YJV)进行不同火源功率和不同气流速度下水平延燃特性研究,对同种聚烯烃护套的隔离型阻燃电缆W DZA+-YJLY(ZG-A)、耐火电缆BBTRZ及矿物绝缘电缆NG-A开展水平延燃特性验证试验。试验表明,YJV和ZR-YJV随供火功率增大,水平延燃长度相应增加,且试验初始气流速度在1.2 m/s左右存在水平延燃长度峰值;WDZA+-YJLY(ZG-A)、BBTRZ和NG-A呈现良好的耐火性能,相应水平延燃长度分别为0.70 m、0.51 m和0.39 m,烟密度峰值均≤0.16,平均值均≤0.10,符合NFPA 262标准要求。

Standard Test Method for Wire and Cable Combustion and Smoking Characteristics （NFPA 262） is referred to design horizontal burning test device of cable, research the horizontal combustion characteristics of PVC insulated cable with cross-linked polyethylene sheath （YJV） and PVC insulated cable with flame retardant cross-linked polyethylene sheath （ZR-YJV） at different fire powers and air velocities and carry out horizontal combustion characteristics test on isolated flame retardant cable WDZA＋ YJLY （ZG-A）, fire resistant cable BBTRZ and mineral insulated cable NG-A with same polyolefin sheaths. The test shows that horizontal combustion lengths of YJV and ZR-YJV increase accordingly with the increase of fire power. The horizontal combustion length reaches the peak when the initial air velocity is about 1.2m/s; WDZA＋-YJLY （ZG- A）, BBTRZ and NG - A show good fireproof performance, with horizontal combustion lengths of 0. 70 m, 0. 51 m and 0. 39 m respectively, smoke density peak ≤ 0. 16, average ≤0. 10, meeting the NFPA 262.