三棱形PDC齿破岩特性数值模拟研究  

Numerical Simulation on Rock-Breaking Performance of Prismatic PDC Cutter

作　　者：程伟 幸雪松 楼一珊[1,2] 朱亮[1,2] 尹彪 Cheng Wei;Xing Xuesong;Lou Yishan;Zhu Liang;Yin Biao(School of Petroleum Engineering,Yangtze University;Hubei Key Laboratory of Petroleum Drilling and Production Engineering;CNOOC Research Institute Co.,Ltd.)

机构地区：[1]长江大学石油工程学院,湖北省武汉市430100 [2]油气钻采工程湖北省重点实验室 [3]中海油研究总院有限责任公司

出　　处：《石油机械》2024年第11期21-28,共8页China Petroleum Machinery

基　　金：油气钻完井技术国家工程研究中心科学研究基金项目“深层超深层岩石力学抗钻特性描述及智能演算方法”(NERCDCT202319)。

摘　　要：常规PDC钻头在研磨性地层中面临磨损严重、吃入困难、机械钻速低等问题。三棱形PDC齿较常规平面PDC齿具有更好的破岩效果,但是关于三棱形PDC齿的布齿参数、齿形参数的优选缺乏依据。为此,通过有限元仿真分析软件建立了破岩仿真模型,开展了三棱形PDC齿破岩机理研究,剖析了在垂向压入和刮切破岩时三棱形PDC齿的力学特性和破岩规律。研究结果表明:垂直压入破岩时,在相同压力作用下,三棱形PDC齿吃入岩石的深度大于常规平面PDC齿,当前倾角γ<15°时,三棱形PDC齿的破岩效果优于常规平面PDC齿;刮切破岩时,三棱形PDC齿的最优前倾角为10°,最优脊面倾角为3°,最优侧转角为2°。现场试验结果表明,在研磨性地层中三棱形PDC齿比常规平面PDC齿表现出更好的耐磨性和耐冲击性,三棱形齿PDC钻头的机械钻速达到常规平面齿PDC钻头的2.37倍。研究结果可为高研磨性地层的PDC钻头优选提供指导和参考。Conventional PDC bit exhibits severe wear,difficult penetration and low rate of penetration(ROP)in abrasive formations.Prismatic PDC cutter is superior to conventional planar PDC cutter in rock-breaking performance,but there is a lack of basis for the optimal selection of cutter arrangement parameters and cutter form parameters.Therefore,a rock-breaking simulation model was built using the finite element simulation software,to understand the rock-breaking mechanism of prismatic PDC cutter and analyze the mechanical behavior and rock-breaking pattern of prismatic PDC cutter during vertical penetration and scraping.The results show that,during vertical penetration,the penetration depth of the prismatic PDC cutter is greater than that of the conventional planar PDC cutter under the same pressure,and the rock-breaking performance of the prismatic PDC cutter is better than that of the conventional planar PDC cutter when the front rake γ<15°.During scraping,the optimal front rake,crest angle and flank angle of the prismatic PDC cutter are 10°,3°,and 2°,respectively.The field test results demonstrate that the prismatic PDC cutter exhibits better wear and impact resistance than the conventional planar PDC cutter in abrasive formations,and the ROP of the prismatic cutter PDC bit is 2.37 times that of the conventional planar cutter PDC bit.The study results provide guidance and reference for the optimal selection of PDC bits used in high abrasive formations.

关 键 词：三棱形PDC齿 布齿参数 齿形参数 仿真模型 破岩规律 钻头优选 

分 类 号：TE921[石油与天然气工程—石油机械设备]