超深井深部盐层抗高温高密度钻井液体系研究

Study on Drilling Fluid System with High Temperature Resistance and High Density in Deep Salt Layer of Ultra-deep Well

在深部地层钻进的过程中,在持续高温作用下,常规钻井液增稠现象严重,流变性与滤失造壁性矛盾突出,易受到盐、膏的污染,导致钻井液性能恶化,维护处理复杂,甚至引发扩径、缩径、坍塌、卡钻等井下复杂情况。本文利用甲酸盐具备的优良性能,提出一套抗高温和抗盐、钙污染的甲酸钾高密度聚磺钻井液体系,以满足深井超深井深部盐层钻井的需要。

In the process of deep formation drilling, under the action of continuous high temperature, the thickening phenomenon of conventional drilling fluid is serious, and the contradiction between rheological property and wall-forming property of filtration is prominent. It is easy to be polluted by salt and paste, which leads to the deterioration of drilling fluid performance, complex maintenance and treatment, and even leads to downhole complications such as expanding, reducing diameter, collapsing and sticking. In this paper, a set of potassium formate high density polysulfide drilling fluid system with high temperature resistance and salt and calcium pollution resistance is put forward by using the excellent performance of formate, so as to meet the needs of drilling deep salt layer in deep well and ultra-deep well.