针对油层非均质性强及油层孔径难以准确预知等特点,提出了镶嵌屏蔽保护油气层技术,该技术利用镶嵌屏蔽剂具有弹性可变性和直径大于储层孔隙直径的特点,使镶嵌屏蔽剂颗粒部分镶在孔隙入口处(不进入孔隙),对较宽孔径分布的油层具有很好的暂堵作用,且有利于反排和渗透率恢复.室内评价结果表明,以镶嵌屏蔽剂为主剂研发的镶嵌屏蔽钻井液具有低侵入、单向封堵、防塌性能好、抗污染能力强及润滑性好等特点,满足了钻井过程中快速钻进及保护油气层的要求,现场应用4口井的平均井眼扩大率仅为6.2％,远低于同区块油井的平均井眼扩大率(12.3％).%In this paper, the technology of mosaic and shielding for reservoir protection is developed, based on the characteristics of heterogeneous reservoirs, which are difficult to predict diameters of formation pores accurately. By using mosaic and shielding agent, with properties of deformability and reasonable particle size, a wide pore diameter distribution reservoir can be plugged well, which the agent particles are set into the entrance of pores, and it is good for permeability recovery and back flow. The laboratory results show that the drilling fluid system has high performances of low invasion, irreversible plugging, wellbore stability, anti-contamination and good lubrication. The applications in 4 wells show that the average hole enlargement is as low as 6.2%, which is much lower than normal of 12.3%.
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