沈北煤田采空区钻井方法优化

Gob Area Drilling Optimization in Shenbei Coalfield

沈北煤田地层松散,含有大段泥岩。泥岩易吸水膨胀引起坍塌,尤其是在采空区采用常规施工方法,钻进十分困难。针对沈北煤田地层地质情况并结合已施工钻井工程的实践经验进行分析,从钻探设备,钻进工艺,技术参数,钻井液配方与维护管理等方面总结了有效的最优化施工方法,在现有条件下能很好地解决钻进中的地层缩径、掉块、漏水和卡钻等问题,保证了钻井工程顺利进行。该方法值得今后在该地区施工过程中加以借鉴和应用。

In the Shenbei coalfield has loose strata with large mudstone segments.Mudstone is water swellable and could lead to caving-in;especially,the drilling in gob area through conventional operation methods is very difficult.In allusion to the strata and geological conditions,combined with completed drilling engineering practical experiences have carried out analysis.From aspects of drilling equipment,technology,technical parameters,drilling fluid formulation and maintenance management have summarized effective optimized operation method.Under available conditions can resolve issues of borehole diameter shrinkage,block dropping,loss of circulation and drill rod sticking very well,as well as ensured drilling engineering goes smoothly.The method is worth to refer and apply to drilling operations in the area henceforth.