东海深部强研磨性地层PDC钻头提速研究

Study on speed-up of PDC bit in deep highly abrasive formations of East China Sea

摘要:

东海海域ZZ区块HG组H3地层发育大套强研磨性砂岩，导致机械钻速低、单只钻头进尺短，造成钻井周期长、作业成本高。为提高该地层钻进效率、缩短钻井周期，在分析地层特征及钻头使用情况基础上，基于现场试验，研究了钻头尺寸、布齿参数与冠部选型和PDC齿型对钻井效果的影响。结果表明，在H3地层中，?215.9 mm钻头较?311.15 mm钻头提速增效显著；深内锥冠部PDC钻头的攻击性更强，机械钻速更高；斧形齿相比平面齿磨损更小，能有效提高单只钻头进尺；旋转齿可有效提升切削刃利用率和散热效果，实现一趟钻进尺1250 m的突破。研究成果为提升该区块强研磨性地层的钻进效率提供了有效技术方案，为海上同类地层油气勘探开发提供了技术支撑，对保障国家能源安全具有重要意义。

Abstract:

The H3 Formation of the HG Group in the ZZ Block， East China Sea， is characterized by the development of thick， highly abrasive sandstone sequences. This challenging geological condition leads to a low rate of penetration （ROP）， short footage per bit， extended drilling cycles， and consequently high operational costs. To improve drilling efficiency and shorten the drilling cycle， this study conducted systematic field trials based on a comprehensive analysis of formation characteristics and historical bit performance records， investigating the impact of bit size， cutter layout parameters， crown profile selection， and PDC cutter type on drilling performance. The results indicate that within the H3 Formation， ?215.9 mm bits demonstrate significantly superior performance in both ROP and efficiency compared to ?311.15 mm bits. PDC bits with a deep inner cone crown profile exhibit stronger aggressiveness and achieve a higher ROP. Furthermore， axe-shaped cutters experience significantly less wear compared to conventional flat-faced cutters， effectively increasing footage per bit. Additionally， rotating cutters substantially improve cutting edge utilization and heat dissipation， enabling a breakthrough of 1250 m in a single run. These findings provide an effective technical solution for enhancing drilling efficiency in the highly abrasive formations of this block， offer vital technical support for oil and gas exploration and development in similar offshore formations， and hold significant importance for safeguarding national energy security.