锥形 PDC 齿破岩机理仿真研究

摘要

Conical PDC cutter as a new break the rock,the theory is still in initial phase in China. By choosing Drucker-Prager criterion as the rock constitutive model,equivalent plastic strain as the failure criterion,the FEA model of rock-cutting by conical PDC cutter was established,which was based on ABAQUS.Through numerical simulation and theoretical analysis,the rock-breaking mechanism of conical PDC cutter was elaborated:shear failure in tangential and tensile fracture failure in lateral direction,“adjacent”effect was also elaborated.The influence laws between rock-breaking efficiency and cutting depth as well as cutting angle were simulated,and the optimal cut-ting angle 20°was selected.The rock breaking model of the conical PDC cutter is plow-breaking of the PDC bit.%锥形 PDC 齿作为一种新型破岩方式，其相关理论在国内研究还处于起步阶段。采用 Druck-er-Prager 准则，以等效塑性应变作为破坏准则，建立了基于 ABAQUS 的锥形 PDC 齿切削岩石有限元分析模型。通过数值仿真、理论分析阐述了锥形 PDC 齿切向上以剪切破坏为主、侧向方向以挤压拉伸断裂破坏为主的破岩机理，以及“相邻”效应，并且数值仿真分析了切削深度、切削角度对锥形 PDC 齿破岩效率的影响规律，优选出最优切削角度20°。研究结果对锥形 PDC 齿为基础的新型 PDC 钻头的设计提供了依据。