高密度水基钻井液流变性控制技术

Rheology control of high density water-base drilling fluid

艾贵成 喻著成 李喜成 穆辉亮 张永海 王卫国

AI Guicheng YU Zhucheng LI Xicheng MU Huiliang ZHANG Yonghai WANG Weiguo

西部钻探国际钻井公司

International Drilling Company of West Drilling Engineering

流变性的控制是高密度钻井液施工的关键技术难题。对高密度钻井液进行了分类，以密度—粒度—黏度曲线确定了最优化加重剂粒度分布，通过优化基浆配制工艺、优选强抑制钻井液体系、优化加重剂与钻井液的粒度分布研究，应用超微细、亚微态粒子稳定技术，强化固相控制，形成一套优化的高密度阳离子钻井液技术工艺。在酒东油田的现场应用表明：对密度1.95～2.20 g/cm3的钻井液，黏度可在55～180 s间调节，n小于0.7,K小于0.9,动塑比值在0.4~0.8之间,Kf小于0.1,较好地控制了流动性和润滑性,降低了黏卡发生率,首次在长301井实现了零事故钻井。

The rheology control is a key technical problem in the high density drilling fluid operation. Through conducting research on the classification of high density drilling fluid, the optimal grain distribution of adulterant is determined using the density-grain-viscosity curve. By conducting research on the optimization of the preparation process of basic mud, the drilling fluid system of strong inhibition, the grain distribution of adulterant and drilling fluid, applying ultra-micro and sub-micro particle stabilizing technique, intensifying solid control, systematic high density cationic drilling fluid technologies are developed. They have been applied to the Jiudong Oilfield. It is indicated that the viscosity of the drilling fluid with its density ranging from 1.95g/cm3 to 2.20 g/cm3 can be regulated from 55 s to 180 s, when the n is less than 0.7 and the K is less than 0.9. The ratio of dynamic shear force value to plastic viscosity is between 0.4 and 0.8, and the Kf is less than 0.1. The rheology and lubricity is better controlled, as well as the sticking less occurs. It enables the Chang-31 well to realize no drilling accidents.