摘要
为了进一步开发渤海油气资源,渤海油田计划实施浅层超深大位移井,以增加泄油面积,提高单井产量。大位移井大斜度段大尺寸井眼钻进过程中,由于环空流体返速低,岩屑传输效应弱,导致井眼清洁困难,易形成岩屑床,严重制约钻井效率,威胁钻井安全。为改善井眼清洁效果,本文在斜井段中引入钻井液浮力的影响,并结合岩屑扩散方程改进了岩屑质量交换效应的计算方法,建立了大位移井岩屑两层动态运移模型,能够准确地模拟大位移井全井段的岩屑动态运移情况。案例分析结果表明,钻进、循环工况交替作用下,大位移井中的岩屑床将形成波浪状分布,有效降低了岩屑在井眼内的大量堆积。结合X井各尺寸井眼清洁情况的分析,对钻井参数进行了优化。同时,提出了岩屑床的控制对策,包括循环间隔和循环时间,为渤海浅层超深大位移井的顺利实施提供了理论依据。
In order to further develop oil and gas resources in Bohai Sea,the shallow ultra-deep extended-reach wells in Bohai Oilfield were planned to be implemented,so as to increase the oil drainage area and enhance the output of a single well.However,during the drilling process of large-sized wellbore sections with high inclination in extended-reach wells,it is difficult to clean the wellbore and easy to form the cuttings bed because of the low return velocity of drilling fluid and weak cuttings transport effect,which seriously restricts drilling efficiency and threatens drilling safety.To improve the wellbore cleaning effect,the influence of buoyancy of drilling fluid in the inclined section was introduced,and the calculation method of cuttings mass exchange effect was improved by combining the cuttings diffusion equation.Then,a two-layer dynamic model for cuttings transport in extended-reach wells was established,which could accurately simulate the dynamic transport of cuttings throughout the entire section of extended-reach wells.The case study shows that under the alternating action of drilling and circulation operations,the cuttings bed in extended-reach wells will form a wavy distribution,effectively reducing the excessive accumulation of cuttings in the wellbore.According to the wellbore cleaning effect of Well X in each section,the drilling parameters are optimized.Meanwhile,control measures for the cuttings bed are proposed,including cycle interval and cycle time,providing a theoretical basis for the smooth implementation of shallow ultra-deep extended-reach wells in Bohai Sea.
作者
张晓诚
孙连坡
李文龙
ZHANG Xiaocheng;SUN Lianpo;LI Wenlong(CNOOC China Limited,Tianjin Branch,Tianjin 300459,China)
出处
《中国海上油气》
CAS
CSCD
北大核心
2024年第4期169-180,共12页
China Offshore Oil and Gas
基金
中海石油(中国)有限公司科技项目“渤海油田稳产3000万吨,上产4000万吨关键技术研究”子课题“莱州湾浅层6000米大位移井钻完井技术研究与示范(编号:CNOOC-KJ135ZDXM36TJ06TJGD202201)”部分研究成果。
关键词
渤海
超深大位移井
井眼清洁
岩屑运移
参数优化
Bohai Sea
ultra-deep extended-reach well
wellbore cleaning
cuttings transport
parameter optimization
