CB3-1双分支水平井钻井工艺

CB3-1 dual-lateral horizontal well drilling technology

石崇东 王万庆 谌建祁 田长春 张虎平 沈建文

SHI Chongdong WANG Wanqing CHEN Jianqi TIAN Changchun ZHANG Huping SHEN Jianwen

长庆钻井工程总公司定向井技术服务公司，陕西西安　710021 西南油气公司川西采气厂，四川德阳　618000 长庆油田第四采油厂，陕西靖边　718500 滇黔桂石油勘探局第一钻探公司，山东临邑　251500

CB3-1 井是长庆钻井总公司在长北气田承担的第1 口双分支水平井，每个分支设计水平段为2000 m，钻探目的层为 山西组山２段。介绍了该井井身剖面优化设计、套管开窗及裸眼侧钻等新技术，针对表层大井眼井壁稳定性差、“双石层”易垮 塌、裸眼侧钻、气层深度不一、轨迹调整频繁、摩阻扭矩预测及分支井所面临窗口再入等一系列技术难题，制定了一整套合理的 技术措施。总结出煤层段钻进的技术要点及适合长北区块的双分支水平井钻井液体系，PBL 循环接头、Agitator Sub 等先进井 下工具的应用确保水平段穿越在最有价值的产层中。CB3-1 井的开发对提高该区块的产能具有重要作用。

Well CB3-1 is the irst dual-lateral horizontal well drilled by the Changqing Well Construction Company in Changbei gas ield, each branch of the horizontal interval is designed as 2,000 meters. The drilling target is the member 2 in Shanxi Formation. The paper introduces the technology of optimization design of wellbore proile, the casing window-opening technology, and the barefoot laterally drilling technology. In view of such problems as the poor wellbore stability of large hole, the easily collapsed “Shuangshi bed”, the barefoot laterally drilling, the different depth of production formations, the frequent trajectory adjustment, the prediction of torque and drag, and window entry of branch wells, systematic reasonable technical measures are established. Technical points of drilling in coal seam sections and the drilling luid system of dual-lateral horizontal wells in Changbei block are summed up. The application of PBL circulation joint, Agitator Sub and other advanced downhole tools ensure that the horizontal section pass through the most valuable production formations. The development of CB3-1 well is very important to improve the deliverability in the block.