定向长钻孔分段水力压裂超前弱化技术

为解决煤层群下行开采时上覆煤柱给下伏煤层带来的顶板管理安全隐患,以榆家梁煤矿43202、43203工作面为工程背景,提出采用定向长钻孔分段水力压裂超前弱化技术对工作面顶板进行卸压弱化;阐述了长钻孔分段水力压裂的基本原理和压裂钻孔的布置原则,根据经验公式优选了压裂层位并对压裂钻孔的布置及压裂参数等进行了设计,利用压裂曲线图和压裂后工作面的矿压观测数据。对压裂成果考察结果表明:采用定向长钻孔分段水力压裂超前弱化技术,钻孔压裂突破点明显,工作面来压步距较小,达到了预期的卸压效果。

Advanced weakening technology of directional long borehole staged hydraulic fracturing

In order to solve the hidden danger of roof management brought by overlying coal pillars to the underlying coal seam when the coal seam group is mining downward, taking the working faces 43202 and 43203 of Yujialiang Coal Mine as the engineering background, this paper proposes to use the technology of directional long hole subsection hydraulic fracturing to weaken the roof of the working face, and expounds the basic principle of long hole subsection hydraulic fracturing and the layout principle of fracturing holes according to the formula, the fracturing horizon is optimized and the layout of the fracturing borehole and the fracturing parameters are designed. The fracturing results are investigated by using the fracturing curve and the observation data of the ground pressure of the working face after fracturing. The results show that the drilling fracturing breakthrough point is obvious, and the pressure step distance of the working face is small, which achieves the expected pressure relief effect.