中文摘要：

针对海洋深水钻井作业所遇到的水基钻井液低温增捌问题,在全面分析低温增稠机理基础上,利用实验室自制的深水钻井液模拟装置,通过优选处理剂,构建了一套具有好的低温流变性的无黏土相海水基钻井液体系。实验结果表明,该钻井液体系经130℃老化后,低温流变性好,老化前后4℃和25℃时的表观黏度之比分别为1.179、1.250,塑性黏度之比分别为1.167、1.240,动切力之比为1.200、1.265,静切力稳定,动塑比变化范围在0.625~0.694 Pa/（mPa·s）之间,API中压撼失量在9.0 mL左右;润滑系数为0.181,页岩水化膨胀率为10.0%,页岩热滚回收率为87.0%,同时具有较强的储层保护能力和较好的抑制天然气水合物生成能力。

英文摘要：

A clay-free seawater base drilling fluid of excellent low temperature rheology was prepared for use in offshore drilling where low temperature viscosification of drilling fluids was frequently encountered. Additives used in the drilling fluid have been optimized on self-made deep water drilling fluid simulation device. This fluid has good low temperature theology after aging at 130 %. Before and after aging, the ratios of apparent viscosity at 4 ℃ and 25 ℃ are 1.179 and 1.250, respectively, the ratios of plastic viscosity at 4 % and 25 ℃ are 1.167 and 1.240, respectively, and the ratios of yield point at 4 ℃ and 25 ℃ are 1.200 and 1.265, respectively. This fluid has stable gel strengths. The PV/YP ratio is in a range of 0.625-0.694 Pa/（mPa-s）, the API filter loss is about 9.0 mL, the coefficient of friction is 0.181, percent shale swelling is 10.0%, and percent shale cuttings recovery in hot rolling test is 87.0%. This fluid also helps protect reservoirs and prevent the generation of gas hydrate.