水平分支井钻完井技术优化及在渤海油田的应用

Optimization of Drilling and Completion Technology for Horizontal Branch Wells and Application in Bohai Oilfield

随着渤海部分油田进入开发中后期,对低产低效井的治理改造愈加迫切,水平分支井技术是实现低产低效井治理的有效手段,但在实际应用中又面临老井井网密集、防碰问题严重,储层易出砂、井壁稳定性差等难题。针对这些难题,通过钻井轨迹优化,克服井眼碰撞问题;优化井身结构和钻井液体系,以保证钻井安全顺利;完井方面优选完井防砂方式,基于多物理场耦合有限元仿真结果对防砂管柱进行结构优化,设计预置导向器,并下入到分支井眼侧钻点下部,实现井壁全支撑。产能显示,A井产量从作业前的5 m^(3)/d增加至45.2 m^(3)/d,半年后产量仍保持40 m^(3)/d,实现稳定生产。这表明通过钻井轨迹优化及精准控制,并配套水平裸眼段井壁全支撑及充填防砂技术可提高单井产量,实现低产低效井高效治理。

As some oilfields in Bohai Sea enter the middle and late stages of development,the treatment and transformation of lowproduction and low-efficiency wells are becoming more and more urgent.Horizontal branch wells technology is an effective measure to achieve the treatment of low-yield and low-efficiency wells.However,in practical applications,they are faced with problems such as dense well net,serious anti-collision problems,easy sand production in reservoirs,and poor wellbore stability.In view of these problems,the wellbore collision problem was overcome by optimizing the drilling trajectory.The drilling safety was ensured by optimizing the wellbore structure and drilling fluid system.In terms of completion,the completion sand control mode was optimized.Based on the multi-physical field coupling finite element simulation results,the structure of the sand control string was optimized,the preset director was designed,and lowered into the lower part of the sidetracking point of the branch wellbore to realize full support of the wellbore.The productivity shows that the production of Well A has increased from 5 m^(3)/d to 45.2 m^(3)/d,and the production remained 40 m^(3)/d half a year later,which has achieved stable production.This shows that through the optimization and precise control of drilling trajectory,and the full support of horizontal open hole section and filling sand control technology,the single well production can be improved,and the efficient management of low-yield and low-efficiency wells can be realized.