高密度油基钻井液在阳101H3-6井长水平段的应用

Application of high-density oil-based drilling fluid in the long horizontal section of Well Yang101H3-6

摘要:

阳101H3-6井是位于四川泸州区块一口页岩气水平井。针对阳101H3-6井长水平段井壁稳定性差、摩阻扭矩高的钻进技术难点，提出了高密度油基钻井液技术对策，引入新型主乳化剂Ⅰ型，通过正交试验，优选确定了密度为2.2 g/cm³的高密度油基钻井液配方为：2%主乳化剂+3%辅乳化剂+3%润湿剂+4%降滤失剂+1%有机土+3%CaO，油水比为80∶20（柴油∶25%CaCl₂水溶液）。性能评价结果表明，该高密度油基钻井液抑制性强，抗污染能力良好，性能稳定。现场实际应用表明，该高密度油基钻井液流变性好，破乳电压高，高温高压滤失量低，满足阳101H3-6井长水平段施工需求。阳101H3-6井水平段钻进过程中钻井液性能稳定，井壁稳定，井下安全，顺利完钻。

Abstract:

In view of the drilling technical difficulties of poor wellbore stability and high friction torque in the long horizontal section of Well Yang101h3-6， high-density oil-based drilling fluid was proposed as the solution. With incorporation of a new “Ⅰ” type main emulsifier， the formulation of high density oil-based drilling fluid was determined at 2.2g/cm³ with the composition of 2% primary emulsifier+3% co-emulsifier+3% wetting agent+4% filtration reducer+1% organic soil+3% CaO， oil-water ratio 80∶20（diesel oil∶25% CaCl₂ aqueous solution）. Evaluation on its performance showed that the system has strong inhibition， good anti-pollution ability， and stable performance； the field application showed that the high-density oil-based drilling fluid has good rheology， high demulsification voltage， low filtration at high temperature and high pressure， meeting the drilling needs for the long horizontal section of Well Yang101H3-6. During the drilling of the horizontal section of Well Yang101H3-6， the performance of the drilling fluid was stable， the borehole wall was stable， and the downhole was safe， leading to smooth completion of the well.