摘要将RVV电缆中的护套、绝缘层与填充物拆分出来,取少部分进行MCC分析,用分析所得数据作图并求出PHRR、THR、LOI等参数,对该样品电缆的阻燃性能进行分析。分析后发现绝缘层的PHRR值和THR值均低于护套,而绝缘层的LOI值大于护套。这说明绝缘层的阻燃性比护套更强。将剩余的电缆护套和绝缘层分割成数段作为实验样品,样品长度为5cm与10cm。在1000W与2000W功率下进行不同距离的加热试验,观察记录该样品电缆包覆材料在高温加热下的现象,发现同条件下电缆护套开始冒烟熔化的时间短于绝缘层的时间。与之前MCC分析的结论相印证。查阅相关资料,结合电缆火灾案例分析电缆包敷材料火灾成因。42771
关键词 电缆 MCC分析 电缆加热试验 火灾成因分析
毕业论文设计说明书外文摘要
Title Simulation of the cable core overheating cause fire
Abstract
The sheath, insulating layer and filling of the RVV cable are peeled off and then a little of MCC was taken out for analysis whose data was then used to plot and figure out its PHRR, THR, and LOI parameters. The fire resistant of the sample cable was analyzed, which showed the PHRR and THR of the insulation layer was lower than the PHRR of the sheath, when the LOI parameter of the former larger than the latter, which indicates that the fire resistance of the insulation layer is stronger than that of the sheath. The remaining cable sheath and insulating layer is pided into a number of segments as experimental samples with the length of 5cm and 10cm. Heating test with different distance between 1000W and 2000W is taken, and the phenomenon in the process of heating cable of coating material in the high temperature was observed and recorded. It was found that the smoking time of the cable sheath was shorter than that of the insulation layer under the same condition. This is equal to the conclusion of the previous MCC analysis. According to the relevant information, reasons for cable package material that caused fire should be analyzed based on concrete cases.
Keywords Cable MCC Cable heating test Analysis of ignition cause
目 次
1 绪论 1
1.1 电缆火灾 1
1.2 电缆火灾主要原因 1
1.3 电缆火灾危害 2
1.4 电缆对火行为测试标准 2
2 聚氯乙烯材料 3
2.1 聚氯乙烯概述 3
2.2 聚氯乙烯结构 3
2.3 聚氯乙烯热性能 3
2.4 聚合物燃烧过程 3
2.5 聚氯乙烯历史发展 4
2.6 聚氯乙烯分类 5
3 电缆材料的MCC分析 6
3.1 实验样品 6
3.2 MCC介绍 6
3.3 护套MCC分析 7
3.4 绝缘层MCC分析 16
3.5 填充物MCC分析 23
3.6 极限氧指数(LOI)分析 29
3.7 最大热释放速率(PHRR)分析 29
3.8 热释放总量(THR)分析 30
4 电缆加热实验