摘要
库车坳陷是塔里木盆地天然气增储上产的主力区域,存在超深、高温高压、复合盐膏层、巨厚高陡砾石层、多压力系统及不稳定地层等地质条件,工程面临井身结构抗风险能力不足、砾石层提速受限、盐膏层溢漏塌卡事故复杂频发以及固井质量差等难题。为此,攻关完成了库车深层钻完井5项关键技术:①膨胀管补贴与三维轨迹优化技术,拓展优化非标准井身结构,增加深部井筒抗风险能力;②高陡砾石层精细化表征及钻井提速技术与配套工艺,形成个性化提速模式,大幅度降低钻井周期;③精细控压钻井与固井技术,应用于高密度窄窗口、复杂压力系统的溢漏同存盐膏层井段,复杂事故处理时间缩短80%以上;④抗高温高密度钻井液与固井液技术,实现深部井段安全优快钻井,有效降低高温、高压盐水及井漏等复杂层位的井下事故;⑤酸溶性堵漏技术,应用于目的层钻进,降低储层污染,平均漏失量降低46%以上。攻关成果加快了库车坳陷3个“万亿方”大气区的勘探开发进程,为超深层天然气高效开发提供了可借鉴的技术。
Kuqu depression,the main area for natural gas storage and production in Tarim basin,is characterized by the complex geological conditions,such as ultra-burial depth,high pressure,high temperature,compound salt formation,steep gravel bed,multiple pressure system,and unstable formation.Drilling and completion engineering are faced with such problems as lack of well structure,limited acceleration for gravel layer,frequent and complex leakage or collapse for compound salt formation,and poor cementing quality.To solve above problems,five key technologies are formed.Firstly,expansion tube subsidy and three trajectory optimization technologies,optimize the non-standard wellbore structure,and improve the anti-risk ability of deep wellbore.Secondly,the refined characterization of gravel bed and auxiliary technologies,helpfully form the personalized accelerated template and greatly reduce the drilling cycle.Thirdly,the precisely managed pressure drilling and cementing technology has been successfully applied to the strata with narrow mud windows with high density,multiple pressure systems,or simultaneous overflow and leakage,which cuts down the complexity treatment time by more than 80%.Fourthly,the high temperature and high-density drilling fluid and cementing fluid system helps effective drilling and reduces the downhole accidents in complex sections such as high temperature,high pressured saltwater and well leakage.Fifthly,the acid soluble temporarily plugging material used for drilling in the target zone significantly reduces reservoir pollution and the average loss rate by more than 46%.Above achievements can provide support for the fast development of natural gas resources and accelerate the exploration process of the three large gas fields with trillion resources in Kuqu depression.
作者
谭鹏
何思龙
李明印
陈雪峰
张景田
马喜伟
TAN Peng;HE Silong;LI Mingyin;CHEN Xuefeng;ZHANG Jingtian;MA Xiwei(CNPC Engineering Technology R&D Company Limited,Beijing 102206 China;PetroChina Tarim Oilfield Company,Korla 841000,Xinjiang,China)
出处
《石油钻采工艺》
CAS
北大核心
2021年第5期580-585,共6页
Oil Drilling & Production Technology
基金
国家科技重大专项“深井超深井钻井关键技术与装备”(编号:2016ZX05020)。
关键词
库车
深层
天然气
钻井
完井
漏失
井身结构
精细控压
Kuqu
deep formation
natural gas
drilling
well completion
lost circulation
well structure
managed pressure