中文摘要：

为了研究不同质量的点火具自身爆炸特性以及对粉尘爆炸下限浓度的影响，采用20L球爆炸测试装置对不同质量的点火具进行了试验，与理论计算结果进行了对比；并对过200目筛、中位径为32μm的煤粉进行了爆炸下限浓度研究。结果表明：试验结果和理论计算结果基本一致，爆炸压力随点火具质量的增加而呈现线性上升；随着点火具质量的增加，煤粉的爆炸压力逐渐增加，爆炸下限浓度逐渐降低，当点火具质量由0．24g增加至2．40g时，煤粉的爆炸下限浓度由40～50g/m3下降到30～40/gm3，引爆煤粉的危险性进一步增大。

英文摘要：

In order to study intrinsic explosibihy of igniters in different quantity and the influence on minimum explosive concentration of coal dust, 20 L sphere explosion test units were employed, and then the experiment results were com- pared with the theoretical calculations. Moreover, coal powders of less than 200 mesh, whose median diameters were 32 μm, were used as dust samples for minimum explosive concentration evaluation. The experimental results show agreement with the theoretical calculations. The explosion pressure has a linear increase with the increasing of ignition quality. With the ignition quaIity increasing, the explosion pressure of coal dust increases and the minimum explosive concentration de- creases conversely. When the ignition quantity increased from 0.24g to 2.40g, the minimum explosive concentration re- duces from 40-50 g/m3 to 3040 g/m3, which indicated that the risk of such dust was further increased.