LPS多元硅钻井液提高二界面胶结强度的研究

针对大庆油田三次加密区多压力层系薄油层，差油层的二界面固井质量问题，通过对井壁围岩，泥饼，水泥石的物理和化学结构，组成和成分的分析，研制了一种多元硅界面增强剂LPS。LPS主要由硅醇，低分子量聚合物，有机成膜剂组成。以LPS为主要处理剂研制出一种新型钻井液体系，研究结果表明，LPS多元硅钻井液体系具有液变必合理，抑制剂强，油气层保护性好，能够提高水泥环－泥饼－地层的胶结能力等优点，经5口三次加密调整井的现场试验证明，LPS多元硅钻井液对井壁有较好的稳定作用，在一定程度，有效地提高了二界面胶结强度，利于提高二界面固井质量；钻井液性能优良，保护油气层效果好，井径扩大率较小，满足大庆油田加密调整井钻井要求。

LPS polyatomic silicon-based drilling fluid improves the cementation strength between interfaces

Based on the analysis to borehole surrounding rock, mud cake, physical and chemical structure and composition of the cement, a polyatomic silicon cementation strength enhancing agent LPS is developed to improve the cementing quality in the thin and poor reservoirs of multi-pressure layers of infilling wells in Daqing oilfield. It is mainly consisted of silanol, low molecular weight polymer, organic filming agent, and a novel drilling fluid system is also developed based on LPS. Study shows that this drilling fluid system has such advantages as good rheology, better shale control ability, free of formation contamination and improvement of cementation strength between the cement ring, mud cake and formation. Field tests in 5 infill-adjustment wells show that this LPS silicon based drilling fluid has good borehole stability and it can control the mud making in the mudstone formation. It suits for fast drilling of adjustment well, and can effectively improve the cementation strength and cementing quality between interfaces. Moreover, good reservoir protection result is achieved, and regular borehole is obtained with small hole enlargement.