Abstract: Drilling fluid with bentonite and high solid phase has been widely used in drilling construction both at home and abroad, which easily causes injury to reservoir and makes reservoir permeability drop a lot. To protect reservoirs, viscosifier, fluid loss additive, inhibitor, and temporary plugging agent were selected, and solid-free drilling fluids were developed, i.e. clean water +0.3%Na₂CO₃+3%FL-1+1%Redu1+0.3%XC+0.3%CMC+1.5%Na-PAN+3%FT-1+2%SPNH+0.2%K-PAM+2%QCX-1. This paper analyses the working mechanism, indoor experiment and application results of solid-free drilling/completion fluids, and points out that the fluids do not only have favorable suspension portability, rheological property, and lubricity, but could also protect reservoir well and meet the requirements of horizontal well drilling in low-pressure reservoir and protect the reservoir.

Key words: solid-free, completion fluid, drilling fluid, reservoir protection

摘要： 国内外石油钻井施工中,多使用含有膨润土和较高固相的钻井液,易对储层造成伤害,使储层渗透率大大降低。为满足储层保护的需要,优选增黏剂、降滤失剂、抑制剂、暂堵剂,开发出无固相钻井液体系,即:清水+0.3%Na₂CO₃+3%FL-1+1%Redu1+0.3%XC+0.3%CMC+1.5%Na-PAN+3%FT-1+2%SPNH+0.2%K-PAM+2%QCX-1。文章分析了无固相钻井完井液作用机理、室内实验及现场应用效果,指出该体系不仅具有良好的悬浮携带性、流变性、润滑性,而且油层保护性能也很好,能够满足低压油层水平井钻进和保护油层的要求。

关键词: 无固相, 完井液, 钻井液, 储层保护