硬地层定向 PDC 钻头个性化设计与应用

摘要

Polycrystalline diamond compact(PDC)bits have been used to drill the homogeneous formation from soft to medium-hard.But in hard and abrasive formation,there are some problems such as low speed and short life.In order to expand the scope in hard formation for PDC bit,the design parameters,such as the bit's profile,cutting structure,working angle,hydraulic structure and factors affecting stability characteristics,were studied and optimally designed.According to the study,the new directional PDC bit (Model 311BTS115E6) was individually designed for Qingshankou and Quantou formation in Changling sag.The field application showed that the new bit reached a penetration rate of average 3.2 m/h in directional section,which was 200%higher than adjacent wells.It also had some other advantages such as high build-up rate,stable tool surface.%为了扩大 PDC 钻头在坚硬地层钻进方面的使用范围,通过对钻头冠部轮廓形状、切削结构、切削齿工作角度、钻头水力结构、稳定特性影响因素等方面的研究和优化设计,针对长岭凹陷青山口组及拳头组地层,个性化设计了311BTS115E6型定向 PDC 钻头。试验表明：新型号钻头在硬地层定向段机械钻速高,平均机速达到3.2 m/h,与临井相同井段钻头相比,钻速提高了200%。且该钻头滑动过程中造斜率高、工具面稳定,具有极高的推广价值。