南246-平309阶梯水平井井眼轨迹控制技术

Trajectory control techniques for the stairs horizontal well,Nan 246-Ping 309

南246-平309水平井位于大庆敖南油田,目的层为葡萄花油层。该井为7靶点的阶梯水平井,设计井深为2121m,实际完钻井深为2153m,水平段长度728.48m,井底水平位移1120m,采用阶梯式水平井进行开发,轨迹控制精度要求高,施工难度大。在施工中由于受地层因素的影响,工具造斜能力下降,使第1靶点不能正常着陆。为此采用大斜度螺杆钻具进行非填井悬空侧钻,自然填埋下井眼的方法,实现了正常着陆。通过调整钻具组合、钻进参数、优化油层套管串结构等,使该井顺利完井,满足了设计要求。不仅取得了较好的经济效益,也为该区块水平井施工提供了宝贵经验。

The horizontal well,Nan 246-Ping 309,is located in Daqing Aonan Oilfield,with Putaohua Formation being its target.The stairs horizontal well has seven target points.The designed depth is 2121 m,but actual total depth is 2153 m.The horizontal interval and displacement are 728.48 m and 1120 m respectively.It requires high control accuracy of hole trajectory to use stairs horizontal wells to develop.Also it is difficult to operate.Due to formation factors,the slant building-capacity of tools gets poorer,which makes No.1 target impossible to land normally.So screwdrills with high angle are applied to carry out non-filling suspended sidetracking.Then the borehole is filled naturally,and as a result normal landing is attained.Based on adjusting drilling assembly,drilling parameters,and optimizing oil casing strings,the well is completed successfully,fulfilling the demand of design.It does not only lead to good economic benefits,but also provides valuable experience for the operation of horizontal wells in this area.