基于有限元法的旋冲破岩提速仿真分析

Simulation Analysis of Rotary Percussion Drilling Based on Finite Element Method

旋转冲击钻井技术是深井、超深井钻井常用的提速措施之一,可以有效提高钻头破岩速率。相较于旋冲工具的迅速发展,冲击参数对钻头破岩效率影响的量化研究还不多见。本文利用有限元法研究旋冲钻井配合PDC钻头的破岩提速机理,研究冲击参数对岩石破碎体积、机械钻速的影响。仿真结果表明:随着冲击载荷增加,冲击破碎坑深度和体积相应增加,增加趋势先快后慢;使用Φ215.9mmPDC钻头旋冲钻井,中硬地层推荐冲击力20~45kN。利用有限元法模拟钻头破岩过程,可针对不同岩性地层、钻头类型、钻井参数进行冲击参数优选,为旋冲工具的参数优选和性能改进提供理论支撑。

Rotary percussion drilling technology is one of the commonly used measures for fast drilling,which can effectively improve the rock breaking rate.In this paper,the finite element method was used to study the rock breaking mechanism of rotary drilling with PDC bit.The simulation results show that as the impact load increases,the depth and volume of the impact crushing pit increase.TheΦ215.9 mm PDC bit with rotary percussion drilling for mediumhard formation is 20~45 kN.By using the finite element method to simulate the rock breaking process of the bit,the impact parameters can be optimized for different lithological strata,bit types,and drilling parameters,which can provide theoretical support for the performance improvement of the rotary tool.