煤(岩)与瓦斯突出是煤矿严重的自然灾害之一，且是一种复杂的动力现象，是地应力、煤层中的瓦斯压力和煤的结构力学性质综合作用的结果。
Coal (rock) and gas outburst is one of intense natural disaster, is also a complicated and dynamical phenomenon, caused by stress, gas pressure of coal bed as well as coal structure.
试验表明，该装置有效地解决了复杂结构煤层钻孔难的问题。
The site application results showed that the device could be effectively to solve the drilling difficulties in seam with complicated structures.
对于煤层结构复杂、变质程度较高的煤类，定性分类较为复杂。
As to the coal seams with complex texture and higher degree of metamorphism, the qualitative division of coal species is more complex.
应用推荐