新场-合兴场区块须家河组难钻地层PDC钻头研制及应用

Development and application of PDC bits for Xujiahe difficult drilling formations in Xinchang-Hexingchang Area

摘要:

针对新场-合兴场区块须家河组地层硬度大、可钻性差、研磨性高、非均质性强等破岩难题，建立了须家河组地层抗钻特性参数剖面，开展了目标层段工程需求及典型钻头失效形式分析，结合不同类型切削齿破岩特性研究，开展了布齿方式优化，提出“圆形+楔形”双排平面混合布齿结构。通过开展钻头受力分析，优化设计冠部轮廓、刀翼结构、保径结构，形成“高导向性+力平衡稳定性”切削结构，最终研制出须家河组难钻地层定制化PDC钻头。现场应用平均机械钻速4.88 m/h，提升41%；平均行程进尺347.16 m，提升104%，为新场-合兴场区块须家河组二段致密砂岩气藏钻井提速突破提供了新的技术手段。

Abstract:

Aiming at the rock-breaking challenges of the Xujiahe Formation in the Xinchang-Heqingchang Block， such as high formation hardness， poor drillability， strong abrasiveness， and significant heterogeneity， this study established a drilling resistance characteristic parameter profile of the Xujiahe Formation. It conducted an analysis of the engineering requirements for the target interval and typical bit failure modes. Combined with research on the rock-breaking characteristics of different types of cutter， the study optimized the cutter arrangement pattern and proposed a “circular + wedge-shaped” double-row planar mixed cutter arrangement structure. Through bit force analysis， the crown profile， blade structure， and gauge protection structure were optimally designed to form a cutting structure with “high guidance + force balance stability”. Finally， a customized PDC bit for the difficult-to-drill formations of the Xujiahe Formation was developed. Field application results show that the average rate of penetration （ROP） reaches 4.88 m/h， increased 41%； the average run length reaches 347.16 m， increased 104%. This provides a new technical means for breaking through the drilling speed bottleneck of the tight sandstone gas reservoir in the second member of the Xujiahe Formation in the Xinchang-Hexingchang Block.