顺南地区目的层以上大井眼优快钻井技术

OPTIMAL FAST DRILLING TECHNOLOGY FOR LARGE-DIAMETER SECTIONS ABOVE TARGET ZONE IN SHUNNAN AREA

顺南地区勘探前景广阔,但存在目的层埋藏深、大尺寸井段长、易井斜、井壁失稳等难点,导致大井眼段钻速低、钻井周期长。为提高444.5 mm大井眼段钻速,通过优选非标139.7 mm钻具,研制四喷嘴牙轮钻头,优化减震器+扶正器钻井工艺及SD涡轮式冲击器钻井工艺,形成了444.5 mm井眼优快钻井技术。针对311.2mm井段易斜、井壁不稳定的问题,改进垂直钻井工具,优选钻井液配方,形成了311.2 mm井眼安全优质钻井技术。研究成果在顺南地区试验5口井,目的层以上平均钻速6.78 m/h,平均用时116.88 d,较前期(顺南4和5井)机械钻速提高71.8%、钻井周期缩短15.6%,为顺南地区安全优快钻井提供技术支撑。

It shows a bright exploration prospect at Shunnan area,but due to the deep burial of target zones,long largediameter sections,deflecting tendency of formations,and borehole instability,ROP is rather low in the large-diameter section,leading to longer drilling cycle. To solve these problems,many new tools and techniques were used. In the 2ndspud,to increase penetration rate of 444. 5 mm section,specific designed nonAPI 139.7 mm drill pipe was selected,cone bits with four nozzles were designed,vibration reducer and BHA stabilizer and SD turbo-hammer were used to get optimal results. In the 3^(rd) spud,to solve borehole instability and uncontrollable deviation problem in 311. 2 mm section,vertical drilling method was used and improved,drilling fluid composition was optimized. Research results have been applied in 5 wells. The average ROP above the target zone was 6.78 m / h,enhanced by 71.8%. Average drilling circle was 116. 88 d,reduced by 15. 6%. They have provided technical support for safe and fast drilling in Shunnan area.