摘要
松科2 井为国际大陆科学钻探计划（ICDP）支持的全球第-口钻穿白垩纪陆相沉积地层的大陆科学钻探井.该井二开（2 840 m）钻遇地层中伊蒙混层、伊利石和高岭石等黏土矿物总含量高达60% 以上,易水化分散导致缩颈和垮塌;二开上部套管？508 mm,下部井径Ф215.9 mm,上下两部分井径相差悬殊而导致岩屑返排困难.通过XRD 衍射矿物鉴定、室内钻井液材料复配以及现场岩心浸泡等实验分析,优选出适宜于大口径Ф311.2 mm 和？215.9 mm 取心工作的低成本钻井液体系.现场应用过程中,钻井液动塑比维持在0.45-0.82 Pa/（mPa·s）,润滑系数控制在0.11-0.14,泥饼黏附系数0.12-0.15,有效解决了携岩困难问题,并降低了长裸眼卡钻风险.在大口径取心试验、正式设计取心与全面钻进等作业频繁更换以及钻井液性能不断调整过程中,井内未发生大的坍塌与掉块,圆满完成了在491.12-510.94 m 段Ф311.2 mm 口径试取心试验,以及1 074.00-1 148.01 m 和1 182.74-1 256.01 m 段的Ф215.9 mm 口径设计取心任务.
SK-2 Well, supported by ICDP (International Continental Drilling Program), is the ifrst continental scientiifc exploratory well in the world which penetrates the continental Cretaceous sedimentary formations. In the second spud (2 840 m), the total clay minerals of illite/smectite layer, illite and kaolinite in the formations encountered by the well was up to over 60%, which are easily hydrated, leading to tight hole and collapse. The upper casing in 2nd spud was ?508 mm, and the lower hole size was ?215.9 mm. The large difference between the upper and lower holes led to dififculty in lfowback of cuttings. Through mineral identiifcation by XRD diffraction, indoor compounding of drilling lfuid materials and experiment on ifeld core soaking, the low-cost drilling lfuid system was selected which was applicable to coring in large holes of ?311.2 mm and ?215.9 mm. In ifeld application, the ratio of dynamic shear force of drilling lfuid was maintained at 0.45 to 0.82 Pa/(mPa·s), the lubricating coefifcient was controlled at 0.11 to 0.14, and sticking coefifcient of iflter cake was 0.12 to 0.15, which effectively addressed the problems of carrying cuttings and reduced the risk of stuck pipe in long open hole. No large collapsing and sloughing occurred downhole during frequent alternating of coring test in large hole, formal designed coring and non-coring drilling jobs and during continuous conditioning of drilling lfuid properties, and the experiments of ?311.2 mm core drilling in 491.12 m to 510.94 m and ?215.9 mm core drilling in 1 074.00 m to 1 148.01 m and 1 182.74 m to 1 256.01 m as designed were successfully completed.
出处
《石油钻采工艺》
CAS
CSCD
北大核心
2015年第3期32-35,共4页
Oil Drilling & Production Technology
基金
国际大陆科学钻探项目"松辽盆地资源与环境深部钻探工程"(编号:12120113017600)
关键词
松科2井
大陆科钻
特殊钻进工艺
钻井液
裸眼
润滑
携岩
取心
SK-2 Well
continental scientific drilling
special drilling technology
drilling fluid
open hole
lubrication
carrying cutting
coring
