基于ABAQUS牙轮钻头轮体速比计算机仿真研究

Computer Simulation Research on Speed Ratio of Roller Body of Roller Bit Based on ABAQUS

研究牙轮钻头的轮体速比,可以提高牙轮钻头的破岩效率。并且研究轮体速比对牙轮钻头的工作原理、岩石破碎机理、钻头的设计分析都有一定的指导作用。运用CERO软件建立三牙轮钻头的几何模型,并将其导入ABAQUS有限元分析软件中,为了节省仿真时间去除牙轮壳体部分只保留与岩石接触的全齿模型,从而建立钻头全齿与岩石接触互作用仿真模型。通过设置边界条件、网格、载荷、仿真时间来观察井底应力分布,通过改变钻压和转速来看三牙轮钻头的牙轮与钻头本体的转速之比变化情况,大大降低了人力、财力和时间成本,从而缩短了试验周期。牙轮的轮体速比随着钻压的增大逐渐增大并最后趋向某一统计平均值,随着钻头转速的增加各牙轮的轮体速比缓慢增大,当达到一定转速时,牙轮的轮体速比达到峰值将不再增加。最后为了验证使用有限元分析软件研究轮体速比的准确性,将其和现场试验进行对比。

The rock breaking efficiency of cone bits can be improved by studying the speed ratio of cone to bit. The research on the wheel speed ratio has a certain guiding effect on the working principle of cone bit, rock crushing mechanism and bit design and analysis. CERO software was used to establish the geometric model of the three cone bit, which was imported into ABAQUS finite element analysis software. In order to save simulation time, the full tooth model of the cone shell which only kept contact with the rock was removed, and the simulation model of the interaction between the full tooth and the rock was established. By changing the WOB and RPM, the rotary speed ratio was simulated, which greatly shortened the human, financial and time costs, and thus shortened the test cycle. It was concluded that the ratio gradually increases as WOB increased and eventually tended to be consistent. As the RPM increased, ratio slowly increased. When a certain speed was reached, the ratio of each cone increases slowly, and the peak value of the wheel body speed ratio of cone would not increase. In order to confirm the accuracy of the experimental results, it was compared with the physical tests done by predecessors.