Abstract: In view of the shortcomings of existing offshore drilling fluids,this paper optimizes common drilling fluid additives and combines sodium silicate with polymeric alcohols, and developes a high⁃blocking water⁃based drilling fluid with strong inhibition, lubricity and suitable for offshore drilling. The final formulation of seawater sodium silicate polyalcohol drilling fluid is: 400 mL seawater+5.0% bentonite+5.0% Na2CO3+0.4% PAC + 0.7% HA resin + 3.0% sodium silicate + 5.0% polyethylene glycol.The performance evaluation of sodium silicate polyalcohol drilling fluid showed that the apparent viscosity of the drilling fluid system was 30.4 mPa·s, the plastic viscosity was 20.3 mPa·s,the dynamic shear force was 13.1 Pa,and the rheological property was superior to the conventional marine drilling fluid system.The rolling recovery rate of the drilling fluid at 80 ℃ reach up to 87.5%,and the shale swelling height of the 8⁃hour soaking shale is 0.44 mm, which can solve the problem of wellbore stability. The experimental data of the anti⁃pollution ability test indicates that the drilling fluid has the ability to resist salt (Ca2+, etc).

Key words: Seawater pulping, Silicate, Polyalcohol, Inhibitory, Water?basic drilling fluid

摘要： 针对现有海洋钻井液的缺点，对常用钻井液添加剂进行优选，并将硅酸钠与聚合醇复合使用，研发一种具有较强的抑制性、润滑性且适合海上钻井使用的高封堵型水基钻井液。最终确定海水硅酸钠聚合醇钻井液的配方为：400 mL海水+5.0%膨润土+5.0%Na2CO3 + 0.4%PAC+0.7%HA树脂+3.0%硅酸钠+5.0%聚乙二醇。硅酸钠聚合醇钻井液性能评价表明，该钻井液体系的表观黏度为30.4 mPa·s，塑性黏度为20.3 mPa·s，动切力为13.1 Pa，流变性优于常规海洋钻井液体系。该钻井液80 ℃的滚动回收率为87.5%，8 h浸泡页岩膨胀率为0.44 mm，能解决井壁稳定问题。抗污染能力测试表明，该钻井液具有抗盐（Ca2+等）的能力。

关键词: 海水配浆, 硅酸盐, 聚合醇, 封堵抑制性, 水基钻井液