页岩油上下地层漏失井控漏提速钻井技术  

Shale oil drilling technology for leakage control and ROP enhancement of absorption wells in upper and lower formation

作　　者：车卫勤 庞茂源 毕丽娜 岳小同 崔锦 王栋 CHE Weiqin;PANG Maoyuan;BI Lina;YUE Xiaotong;CUI Jin;WANG dong(Directional Well Drilling Company of CNPC Bohai Drilling Engineering Company Limited,Tianjin 300280,China)

机构地区：[1]中国石油渤海钻探工程有限公司定向井技术服务分公司,天津300280

出　　处：《石油钻采工艺》2024年第2期137-146,共10页Oil Drilling & Production Technology

基　　金：渤海钻探公司科技重大专项“青海油田深井钻井提速配套技术研究”(编号:2019ZD19Y);渤海钻探定向井公司“青海英雄岭页岩油水平井优快钻井技术研究与应用”(编号:2023DDDC08Y)。

摘　　要：国内页岩油钻探技术趋于成熟,但钻探过程中依然存在钻井液漏失严重、机械钻速低和钻井周期长等问题,严重制约着页岩油开发的提速提效。通过分析青海页岩油前期6口井钻井数据,在明确了地层复杂情况和漏失特点基础上,将常规四开井身结构精简为二开,减少套管层序的同时实现固封漏失地层;根据漏失类型选择钻井液体系,通过改进BH-WEI钻井液关键处理剂配比,提高钻井液的稳定性、抑制性和封堵性,降低漏失量,实现有效预防漏失;同时,将螺杆钻具上下扶正器距离调整为12 m,降低滑动钻进比例;通过优化PDC钻头结构,水平段采用“高造斜率旋导ATC+低速直螺杆”定向工具等钻井技术,提高机械钻速,形成了青海页岩油控漏提速关键钻井技术。在青海页岩油区块的8口井应用了该技术,与前期钻探的6口井相比,平均单井漏失量由335.02 m^(3)降至21.08 m^(3),机械钻速由4.45 m/h提高至7.36 m/h,钻井周期由94.77 d缩短至68.26 d。现场应用结果表明,该技术可解决青海页岩油钻井技术难点,为青海页岩油资源的有效开发提供了技术支撑。Domestic shale oil drilling technology is becoming more mature than ever.However,such challenges are still present in drilling process,including severe drilling fluid leakage,low rate of penetrate,and longer drilling cycle,which seriously restricts the efficient development of shale oil.In order to solve these challenges,through analysis of drilling data of earlier 6 shale oil wells,this article clarifies the complex geological characteristics and leakage characteristics in Qinghai shale oil formations.The wellbore configuration is simplified to two spud from conventional four spud to reduce casing programme and solidify the thief formation.The drilling fluid system is selected based on leakage type,and the formula of key agent of BH-WEI drilling fluid is modified to improve the stability,inhibition,and sealing of drilling fluids,thereby lowering the leakage and achieving effective prevention of leakage.Meanwhile,the distance between the upper and lower centralizers of screwdrill is adjusted to 12 m,thus reducing the sliding footage ratio.ROP is enhanced by optimizing PDC drill bit arrangement and adopting high build-up ratio rotary steering tool ATC and low-speed straight screw rod,which shapes the shale oil drilling technology for leakage control and ROP enhancement.This technology was applied in 8 wells in Qinghai shale oil block,compared with 6 earlier drilling wells which shows the leakage of single well has been reduced from 335.02 m^(3) to 21.08 m^(3),ROP increased from 4.45 m/h to 7.36 m/h,and the average drilling cycle shortened to 68.26 days from 94.77 days.The field application demonstrates that this technology is a solution to shale oil drilling challenges in Qinghai oilfield and offers technical foundation for the efficient development of shale oil in this region.

关 键 词：页岩油 钻井液漏失 防漏 井身结构 工程技术 

分 类 号：TE242[石油与天然气工程—油气井工程]