钻孔偏斜原因分析及纠斜技术应用

Cause of Hole Deviation and Application of Deviation Correction Technology

贵州贞丰烂泥沟金矿钻探项目开工后,方位倾角屡屡出现偏差。在对测斜仪,钻机安装等问题进行排查后,发现钻孔偏斜主要是由于地层倾角大且软硬互层造成岩石各面受力不均。针对钻孔偏斜,目前国内有螺杆钻纠斜技术,但成本较高。地质钻探工作者采取了加入扶正器进行导正的方法,但效果不理想。针对项目现场的具体情况,技术组对采用加大钻头扩孔,钢粒(携带石英砂)钻进、特制扩孔器钻头扩孔、螺杆马达纠斜等方案进行了论证。在做好相关措施防斜后采用了简单且成本较低的钢粒(携带石英砂)钻进的方法纠斜,纠斜成功并达到地质目的。

Hole deviation frequently occurs in the exploration boreholes of the Lannigou Au deposit,Zhenfeng,Guizhou.The steeply dipping and soft-hard interbedded rocks are responsible for the hole deviation.This study has a discussion on four methods of the hole deviation correction such as reaming bit drilling,steel grain(caring quartz sand)drilling,special reamer bit drilling and screw motor drilling.Finally,steel grain(caring quartz sand)drilling method is used for correcting the hole deviation which serves its geological purpose.