厄瓜多尔TARAPOA区块水平井钻井液关键技术

KEY DRILLING FLUID TECHNOLOGY FOR HORIZONTAL WELLS AT TARAPOA BLOCK IN ECUADOR

厄瓜多尔TARAPOA区块大斜度井段经常出现高摩阻大扭矩、遇阻现象频发、卡钻时有发生,并且在大斜度井段出现的卡钻,没有成功解卡的先例;再加上井身结构的进一步简化和环保条款的硬性规定,使得大斜度井段施工难度进一步加大。针对上述难题,在厄瓜多尔政府环保要求的基础上,选择有利于环保处理剂,研制出了一种性能稳定、防塌能力突出、润滑性好、携砂能力强、环保性能理想等特点的GAP钻井液体系。现场应用结果表明,该体系表现出良好的井壁稳定能力、润滑减阻和井眼净化能力,有效解决了泥页岩和砾石层所带来的的缩径扩径、坍塌掉块、高摩阻大扭矩、钻头泥包等技术难题,在整个斜井段施工过程中井壁稳定,起下钻畅通无阻,首次将3 133 m长的?244.4 mm技术套管一次性下到预定位置。

There were lots of problems such as high friction& torque happened in the high deviated hole section at TARAPOA block in Ecuador. Pipe stuck happened without any successful sticking freeing experience. The request of simplification of well casing program and environmental protection make drilling operation even harder. To solve those above problems,on the basis of Ecuador government's environmental protection requirements,with environment friendly drilling fluid agents,the GAP drilling fluid system has been developed,with high stability,outstanding anti-caving capability,good lubricity,high sand-carrying capacity,and good environmental performance.Field application results show it performs well in borehole stabilizing,lubrication and hole cleaning,effectively having avoided the problems like borehole undergauging or enlargement,high friction and torque,bit balling and so on in shale and gravel layers. In the whole drilling process of the deviated section,the borehole was stable and no sticking during tripping,3133 m of244. 4 mm casing string was run to the preset depth without any obstacles for the first time.