渤海油田油气井侧钻设计方法优化分析

Optimization design method for sidetracking wells in Bohai Oilfield

摘要:

渤海油田低效井侧钻是稳产增产的重要手段之一。优化侧钻方案实现降本增效是精细化侧钻的研究重点。本文系统介绍了侧钻井设计方法，基于对低效井与侧钻井位进行合理匹配，优选侧钻井段，确定深部侧钻和浅部侧钻方案，针对浅部侧钻方案提出了隔水导管重入方案、隔水导管鞋下裸眼侧钻方案、表层套管段开窗侧钻方案、表层套管鞋下裸眼侧钻方案的适用条件与难点，针对深部侧钻方案提出了生产套管开窗侧钻方案、生产套管鞋下裸眼侧钻方案的优选流程。并以渤海某油田2口低效井A井与B井为例，进行了槽口优选、侧钻井段优选、侧钻点优选，最终通过互换2口井的侧钻井位，节约进尺1428 m。现场实施结果表明本次2口低效井侧钻方案合理，能够实现降本增效的目的。本文提出的低效井侧钻优选方法对渤海油田低效井侧钻设计具有一定的指导意义。

Abstract:

Sidetracking from low performance wells in Bohai Oilfield is one of the important means to stabilize and increase production. Optimizing the sidetracking plan to achieve cost reduction and efficiency enhancement is the research focus of the refined sidetracking well design. This paper systematically introduces the sidetracking well design method. The sidetracking section is optimized through properly matching of the low-performance well location and the sidetracking well location; for the shallow sidetracking plan, several technical solutions are presented, including riser reentry, open hole sidetracking from under the riser shoe, sidetracking from surface casing by window-milling, as well as the applicable conditions and difficulties in open hole sidetracking from under the surface casing shoe; for the deep sidetracking plan, the optimal flow chart for sidetracking from the milled window on production casing and sidetracking from under production casing shoes is proposed. Taking two low-performance wells A and B in Bohai as an example, optimization of the drilling slots, the sidetracking well sections was performed. With interchange of the sidetracking target locations of the two wells, the drilling amount was reduced by 1428m. The field application results show that the sidetracking plan for the two low-performance wells are rational and can achieve the purpose of cost reduction and efficiency enhancement. The optimal method of low-performance well sidetracking proposed in this paper can provide some guidance for the sidetracking design for low-performance wells in Bohai Oilfield.