摘要
常规平面齿PDC钻头在钻井时问题突出,如磨损严重、崩齿频繁、进尺短,导致钻井效率低、成本高。为了提高吉木萨尔页岩油钻井勘探开发速度,降低成本,开展了新型多棱齿PDC钻头研究。页岩地层层理性特征较为明显,岩性硬度较高。在建模时,不考虑岩石孔隙和钻井液所产生的影响,忽略切削过程中温度和磨损情况,以简化计算条件;考虑页岩各向异性,采用Drucker-Prager屈服准则描述页岩力学行为构建有限元模型。切削破岩仿真结果表明,多棱齿相较于平面齿优势明显,其接触应力分布均匀,所受应力更小,载荷波动幅度低,能有效解决岩石“抱团”问题,大幅提升破岩效率。在吉木萨尔页岩地区实钻应用中,新型多棱齿的PDC钻头在单只钻头进尺和平均机械钻速等方面均表现优异。与常规平面齿钻头相比,平均机械钻速提高35%,平均单只钻头进尺提高81%。新型多棱齿PDC钻头的良好破岩效果可为页岩地层钻头优选提供重要参考。
Conventional planar-cutter PDC bit exhibits prominent problems in drilling,such as severe wear,frequent cutter breakage and short footage,resulting in low drilling efficiency and high cost.To improve the drilling speed and reduce the drilling cost in Jimsar shale oil formation,research on novel multi-edged PDC bit was carried out.The shale formation has apparent bedding characteristics,and its hardness is high.In modeling,the effects of rock pores and drilling fluid were not considered,and the temperature and wear in the cutting process were ignored to simplify the calculation conditions.Considering the anisotropy of shale,a finite element model was built by using Drucker-Prager yield criterion to describe the mechanical behavior of shale.The rock cutting simulation results show that the multi-edged cutter has obvious advantages over the planar cutter:its contact stress distribution is more uniform,the stress on it is smaller,and the load fluctuation range is low,which effectively solves the problem of rock“cohesion”and greatly improve the rock breaking efficiency.In the actual drilling of Jimsar shale formation,the novel multi-edged PDC bit shows excellent performance in both footage per bit run and average rate of penetration.Compared with conventional planar-cutter bit,the novel design improves average rate of penetration by 35%and average footage per bit run by 81%.The good rock breaking effect of the novel multi-edged PDC bit provides an important reference for bit optimization of shale formation.
作者
臧传贞
Zang Chuanzhen(PetroChina Xinjiang Oilfield Company)
出处
《石油机械》
北大核心
2025年第9期29-36,共8页
China Petroleum Machinery
基金
中国石油天然气集团有限公司重大科技专项“陆相页岩油规模增储上产与勘探开发技术研究”课题五“陆相页岩油钻井提速提质关键技术研究”(2023ZZ15YJ05)。
作者简介
臧传贞,高级工程师,生于1981年,2005年毕业于中国石油大学(北京)石油工程专业,现从事水平井、超深井钻完井技术研究及管理工作。地址:(834099)新疆克拉玛依市。email:zangchz@petrochina.com.cn。
