超深大位移井高效井筒清洁与预校深一体化提效工艺

超深大位移井的井眼轨迹复杂、井斜大、稳斜段长，常规套管程序为ϕ244.5 mm套管与ϕ177.8 mm尾管复合，且刮管洗井阶段存在随钻预校深为射孔备用的需求，常规采用两趟管柱分别实现井筒清洁、随钻预校深的功能，造成井筒清洁效率低、作业周期长。通过集成优化组合多功能清洁工具、可变径刮管器、随钻测井工具和分流转向阀工具，设计形成了高效井筒清洁与预校深一体化管柱结构，重点开展了水力学模拟、管柱安全评价、工艺流程优化，实现复合井筒一趟式高效清洁和随钻预校深一体化功能，相比常规两趟式方案提效30%。该技术在东海3口超深大位移井中成功应用，井下工具工作正常，相比同类井型常规工艺单井平均缩短43.6 h，具有显著的提速提效作用。

Ultra-deep and large displacement wells have complex wellbore trajectory, large well deviation and long stable deviation section. The conventional casing program is a combination of ϕ244.5 mm casing and ϕ177.8 mm liner, and there is a need to pre-calibrate the depth while drilling for perforation during the scraping and washing stage. Normally, two trips of string are used to achieve the functions of wellbore cleaning and pre-calibrating while drilling, resulting in low wellbore cleaning efficiency and long operation cycle. Through the integration and optimization of multi-functional cleaning tools, variable gauge casing scratcher, logging tools while drilling and diverter valve tools, the integrated string structure of efficient wellbore cleaning and pre-calibrating depth is designed. Hydraulic simulation, string safety evaluation and process flow optimization were carried out to realize the integrated function of one-trip high-efficiency cleaning of composite wellbore and pre-calibration while drilling. Compared with the conventional two-trip scheme, the efficiency was increased by 30%. The technology has been successfully applied in three ultra-deep and large displacement wells in East China Sea, and the downhole tools work normally. Compared with the conventional technology of the same well type, the single well is shortened by 43.6 hours on average, which has a significant effect on speed-up and efficiency improvement.