涪陵江东与平桥区块页岩气水平井井眼轨迹控制技术

Wellbore Trajectory Control Techniques for Horizontal Well in the Jiangdong and Pingqiao Blocks of the Fuling Shale Gas Field

涪陵江东与平桥区块断层发育、地层倾角大,水平井井眼轨迹控制存在着与地质预测偏差大、轨迹调整频繁、中靶难度大和定向托压严重等难题,为此,开展了井眼轨道参数及剖面优化设计,钻具组合与钻井参数协同优化等研究,引入了旋转导向技术和近钻头随钻测量技术等导向钻井技术,配套了超短保径PDC钻头、PDC-牙轮复合钻头及水力振荡器等降摩减阻及提速工具,形成了适用于涪陵江东与平桥区块的水平井井眼轨迹控制技术。现场应用表明,通过井眼剖面优化、钻具组合及钻进参数协同优化等措施,提高了定向施工效率;应用旋转导向和近钻头随钻测量等导向钻井技术,机械钻速提高161%,储层钻遇率达到90%以上;通过配套降摩减阻及提速工具,机械钻速提高20%以上,定向托压现象得到缓解。涪陵江东与平桥区块水平井井眼轨迹控制技术为钻井提速提效、加快产能建设提供了技术支撑。

The geological conditions of Jiangdong and Pingqiao Blocks can be characterized as fault development and significant stratigraphic traps.Trajectory control in horizontal well drilling encountered large deviations in geological prediction,frequent trajectory adjustments,difficulty in hitting the target,heavy directional back pressures and other challenges.To solve these technical problems,research was conducted in wellbore track parameters and profile optimization,collaboration and optimization of drilling tools' assemblies and drilling parameters and the introduction of rotary steering system,near-bit MWD and other guided drilling techniques.In addition,operations deployed gauge protecting PDC bits,mixed bits,hydraulic oscillators and other trajectory control techniques in horizontal well drilling in the Jiangdong and Pingqiao Blocks of the Fuling Area.Field application results showed that direction drilling operation efficiency can be enhanced significantly through borehole profile and drilling parameters optimization as well as the deployment of optimal drilling assemblies.Through the application of a rotary steering system,near-bit MWD and other guided drilling techniques,the rate of penetration(ROP)can be enhanced for 161%,whereas the drilling rate in high quality reservoirs achieved 90% or more.Through the comprehensive deployment of friction reduction tools,the ROP can be further enhanced for more than 20%,whereas direction backing pressures can be minimized effectively.The innovative wellbore trajectory control techniques in drilling horizontal wells in Jiangdong and Pingqiao Blocks,Fuling Area can effectively remove relevant difficulties and might provide reliable support for productivity enhancement.