关键词:

扩眼尺寸, 窄间隙固井, 有限元分析, 准噶尔盆地南缘, 深井超深井

Abstract:

The determination of the reamer size（the desirable reamed borehole size） is a global challenge for research on reaming in drilling. To ensure smooth drilling and cementing of reamed borehole sections，an in-depth case study of Well H101 drilled in the southern margin of Junggar Basin was performed to identify the affecting patterns of the reamed borehole size on drilling，tripping and cementing operations. The requirements for the reamer size were analyzed from perspectives of the drilling tool bending deformation，pump rate optimization，BHA vibration，swab and surge pressure during tripping and fluid density window，surge pressure of running liners，equivalent circulating density（ECD） during cementing，and wellbore integrity incorporating wellbore curvature，and the impacts of changes in casing sizes on cementing of the reamed borehole section were investigated. Finally，the above analyses were combined with a mathematical statistical approach to comprehensively determine the reamer size. The determined reamer size was applied to Well H101 and analogous wells in the southern margin of Junggar Basin，which were all found with smooth drilling operations after reaming，and moreover，Well H101 delivered a daily penetration of 101 m for the reamed borehole section. The presented method and strategy for the reamer size optimization incorporate more factors and are more reliable. They provide important references for determining the reamer size of to-be-reamed wells. 

Key words:

reamed borehole size, narrow clearance cementing, finite element analysis, southern margin of Junggar Basin, deep and ultra-deep well