旋挖钻机碎岩计算方式的分析探讨

Discussion about Calculation Methods of Rock Fracturing by Rotary Drill

结合外载碎岩基本现象,对旋挖碎岩基本过程进行分析,得出其在回转钻进情况下的螺旋破碎的碎岩形式。然后根据岩石破碎时的压入条件,以单个截齿为研究模型,得出轴向压力的理论计算公式,继而参考库伦纳维的内摩擦理论,得出了切削力的理论计算公式。根据不同钻具形式,将单个截齿的计算公式扩展,得到了旋挖钻机压力和扭矩参数的计算公式。将轴向力与切削力计算公式中在特定工况下的影响因子简化,得出了旋挖钻机钻进过程中进尺速度与切削力的理论关系。最后利用LS-DYNA动态分析软件模拟了单个截齿在不同侵深条件下的切削力变化曲线,并将曲线与同等工况下理论计算的曲线进行对比,得出单个截齿的入岩参数理论计算公式。可为入岩旋挖钻机设计提供参考。

Combining with basic phenomenon in rock fracturing by external load, the analysis is made on the process of crushing rock by rotary drilling to get the helical breaking form. Based on the conditions of pressing into the rocks and se- lecting a single cutting pick as calculation model, the theoretical formula of axial pressure is obtained; then with the refer- ence of Coulomb-Navier internal friction theory, the theoretical calculation formula of cutting force is obtained. According to different types of drilling tool, the calculation formula of single cutting teeth is extended, the formulas for calculating the pressure and torque parameters of rotary drilling rig are obtained. The influence factors under specific conditions in the axial force and cutting force calculation formulas are simplified, the theoretical relationship between drilling penetration rate and cutting force in rotary drilling process is obtained. Finally, by dynamic analysis software LS - DYNA, change curve of cut- ting force of single pick in different drilled depth is simulated, and the comparison is made on the simulated curve and the theoretical calculated curve under the same condition to get the theoretical calculation formula for cracking parameters of single pick, which can be reference for the design of rotary drilling rig.