IMPACT OF DRILLING FLUID SYSTEM ON STABILITY OF SHALE FORMATION AND BOREHOLE

摘要

Borehole instabilities pose significant challenges to drilling and completion operations, particularly in regions with weak bedding planes and pre-existing fractures where formations have strong anisotropies. Wall collapse, necking, leakage protection, other issues, reservoir quality and safety issues have universal drilling borehole instability caused by the surrounding rock, and the annual cost consumption in dealing with complex issues is hundreds of millions dollars, and the pace of development of oil and gas exploration and drilling as an artificial factor imposed a serious constraint that impacted the wall surrounding rock stability. It can be seen from the performance evaluation that silicate base drilling fluid is characterised by high inhibitive and low cost, which is also environmentally friendly. The favourable rheology of this drilling fluid can be controlled by pH and it can not be lower than 11 in the practical application.