φ235.00 mm drill bits was adopted at Es4 of Wen 23 gas storage reservoir in the Zhongyuan area was beneficial for gas injection.There were many difficulties in horizontal well drilling,such as wellbore instability in high shale content,carry sand difficulty because of unconventional wellbore,directional underpinning often occurs at short-radius horizontal well mode and large dogleg degrees.The use of environmentally friendly near oil-based drilling fluids with mechanisms and performance comparable to oil-based drilling fluids could help solve the above problems.The application of 2 wells showed that,(1)a long peri-od of wellbore stability of the drilling fluid for the mudstone of Es4 formation.(2)Good lu-bricity,normal orientation and low tripping friction.(3)Strong carrying capacity,which ensures the borehole cleaning.It was the great significance for shortening drilling and completion pe-riod,reducing drilling costs,and deployment of the Wen 23 gas storage reservoir.
关键词
近油基/水基钻井液/井壁稳定/水平井
Key words
near oil-based/water based drilling fluid/wellbore stability/horizontal well
维普
万方数据