深层煤层气防塌钻井液优化研究OA

The instability and blockage of the wellbore in the Yichuan Huanglong area of Liaohe Oil field seriously restricts the development process.In response to the problem of wellbore instability in deep coalbed methane well A in the region,the mineral composition and micro-structure of coal rock are analyzed,and the mechanism of wellbore instability is revealed.It is found that the infiltration of filtrate during drilling is prone to hydration,expansion,and crack propagation,resulting in wellbore instability.A collapse prevention drilling fluid system which is suitable for the region has been constructed,characterized by strong sealing,strong inhibition,as well as good rheological and high-tempera-ture resistance.And it has shown good performance in on-site applications,provided effective technical support for the efficient development of deep coalbed methane wells.