改进抽放方法提高瓦斯抽放效果

分析了回采工作面回采过程中顶板覆岩卸压移动规律及其顶板覆岩结构与关键层层位对覆岩移动规律的影响，提出了利用采动煤层顶板覆岩卸压裂隙发育特征，实施覆岩卸压区走向长钻孔抽放瓦斯.给出了顶板走向长钻孔卸压抽放的合理布置区域，并在抽放钻孔内下入套管，增加了钻孔有效抽放时间和长度，完善了顶板走向钻孔抽放瓦斯的技术，取得较为理想的瓦斯抽放效果.

Improving method and increasing effect of gas drainage

Analyzed the movement law of unloading press of roof rock and the influence of the roof rock structure and the key seam changing on it,and put forward a method of long drill gas drainage to the unloading press area strike,by using the developing character of its cracks.Later,it lays the proper array area of the long drill,and inside the drills there are tubes to increase the drainage time.Therefore,it improves the technology of long drill gas drainage of the roof strike and gets a better drainage result.