聚合醇钻井液体系的研究与应用

STUDY AND APPLICATION OF THE POLYOL DRILLING FLUID SYSTEM

大斜度定向井钻井施工过程中 ,使用常规水基钻井液体系钻井 ,常常出现因井斜角大而引起的高摩阻 ,给钻柱旋转及起下钻操作带来困难。对聚合醇钻井液体系进行了试验研究 ,结果表明 ,钻井液流变性及滤失量变化很小 ,抗老化性能提高 ,抗温达到 12 0℃ ,降摩阻率达 5 0 %。现场应用表明 ,润滑性好 ,钻井液中粘土的水化膨胀被抑制 ,具有较强的抑制防塌作用 ;岩心渗透率提高 2 0 %,达到 87.3 %,对油气层有较好的保护作用。结合在文3 3— 196井的现场应用 ,提出这种新型钻井液体系特别适用于大斜度定向井、复杂井和探井。

When using the conventional water based drilling fluid for high angle deviated directional well drilling, high friction is often caused by the high deviation angle during rotary drilling and tripping. Experimental study is carried out on the polyol drilling fluid system, and results show that there are minor changes found on the rheological property and fluid loss; the aging resistance is greatly improved, and the temperature resistance reaches 120℃, friction rate reduces by 50%. Field using indicates that the system has good lubricity, and the clay hydration is inhibited, which effectively prevents the hole from collapsing. The rock permeability improved by 20%, which is 87.3%, and this is beneficial for formation protection.