针对辽河油田法哈牛区块地层造浆严重、井壁失稳问题突出、连续管钻井携岩困难及黏卡几率高等难题,优选了聚胺抑制剂、封堵剂和高效润滑剂,形成了一套强抑制水基钻井液体系.室内性能评价表明,该钻井液抗温180 ℃,抗盐20%,抗钙5%,抗钻屑25%,岩屑滚动回收率98.7%,岩心渗透率恢复值大于90%,能封堵0.1~0.3 mm裂缝,并具有较高的承压能力和抗返排能力,润滑性能与油基钻井液相当.强抑制水基钻井液在法51-新161C连续管现场试验井应用过程中性能稳定易调整,携砂能力强,机械钻速高,井径规则,储层保护效果明显.研究表明,强抑制水基钻井液完全满足泥页岩地层连续管钻井施工的技术需求,具有推广应用价值.%Fahaniu Block in Liaohe Oilfield is faced with serious mud making, prominent borehole wall instability, difficult rock carrying during coiled tubing drilling and frequent sticking. To solve these problems, a strong-inhibition water based drilling fluid system was developed after polyamine inhibitor, blocking agent and high-efficiency lubricant were selected. And then its performance was evaluated in laboratory. It is shown that this system is resistant to the temperature of 180 ℃, the salt of 20%, calcium of 5% and drilling cuttings of 25%. Its rolling recovery rate of cuttings is 98.7%, and core permeability recovery is more than 90%. It can block the fractures of 0.1-0.3 mm. And furthermore, its pressure bearing capacity and flowback resistance are higher and its lubricity is similar to that of oil based drilling fluid. When this strong-inhibition water based drilling fluid was applied in Well Fa 51-NEW 161C, the field test well of coiled tubing, its performance was stable and adjustable and drilling was improved with excellent sand carrying capacity, high rate of penetration (ROP), regular well diameter, and remarkable reservoir protection effect. In conclusion, this strong-inhibition water based drilling fluid system can meet the technical requirement of the coiled tubing drilling in the mud shale formation and it is worth popularizing and applying.
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