Grey correlation analysis and applications of drill stem failure in drilling engineering

During the drilling process in Hailar region of Daqing Oil field, the drill stem failure frequently happens, which seriously impacts the exploration and development in the region. In order to identify the root causes of drill stem failure in the region, using the grey theory method, run a grey correlation analysis on the affecting factors, which may lead to fail in drill tool during the drilling process in this region. The results show that the main reasons for drill stem failure in the region, is the high value of formation drillability, many faults, corrosion in the process of storage and drilling, and high temperature of the bottom hole. Finally, based on the results of the grey association analysis, from weakening the main affecting factors of drill stem failure, we can put forward to eight measures to prevent drill stem failure, which are fit for this region.