【作者】 李文；

【导师】 叶海旺；

【作者基本信息】 武汉理工大学 ， 采矿工程， 2013， 硕士

【摘要】 随着露天矿山大型化、机械化、自动化、无人化、连续化作业的发展,露天采矿机的应用将越来越普及,不仅在煤岩等软岩矿山开采中发挥了重要作用,还将在石灰岩等中硬岩矿山发挥其重要作用。为了合理利用露天采矿机高效开采,在了解矿岩特性条件的基础上,需对露天采矿机截齿破岩规律及其相关结构参数和工作参数有足够的了解。文中采用动力学理论对露天采矿机滚筒截齿的运动及受力进行了分析；通过建立截齿破岩几何模型对截割力进行了推导；结合ABAQUS有限元软件建立了截齿截割破岩数值模型,针对于单齿作用和双齿同步作用下考虑截齿截割速度、截割深度及截线距的变化对截齿截割破岩过程的影响进行了数值模拟；基于数值模拟结果对露天采矿机截齿破岩规律及截割参数优化进行了研究。所取得的成果总结如下：(1)露天采矿机截齿的运动为随机器的牵引运动与滚筒的自转运动的合成运动。其运动轨迹线为在牵引方向伸展的平面摆线。截割系统(截割滚筒与截齿)受力包括切割滚筒系统自身的重力、行走驱动系统施加的推力、转动驱动系统施加的扭矩以及截齿与矿岩接触后会产生截割阻力。(2)在截齿截割作用下,矿岩单元的破坏是拉-压联合作用的结果,拉损伤相对于压损伤先作用于矿岩单元；压损伤单元的体积较拉损伤单元的体积略大；在与截齿接触处矿岩单元的破坏主要是压损伤,矿岩内部及表面单元的破坏主要是拉损伤。通过对比单齿与双齿截割破岩结果,拉损伤体积最大增量百分比为172.5%,压损伤体积最大增量百分比为169.9%；沿截割方向损伤范围增大了60%,垂直于截割方向增大了56.7%。(3)基于三种因素(截齿截割速度、截割深度、截线距)正交组合工况的截齿截割破岩数值模拟结果,得出了特定岩性条件下不同工况下的最佳参数匹配模式。综合上述三种情况下的分析,得出的最佳截割参数匹配模式为：截割速度为0.45m/s、截割深度为11cm、截线距为14cm。通过以上对露天采矿机截齿破岩数值模拟的研究,有助于对露天采矿机截齿破岩规律的深入认识,以及为国产类似机械设备的研发与改造提供一定的理论基础。更多还原

【Abstract】 Along with the mine’s large-scale, mechanized, automatic, unmanned and continuous operation development, the application of surface miner will be much more popular. It not only plays an important role in mining of soft rock mines such as coal, but also in hard rock mines such as limestone. In order to make rational use of surface miner for high-efficiently mining, the rock failure law of surface miner and its configuration parameters and working parameters should be fully studied at the basis of the understanding of rock conditions.In this article, the movement and force of drum and bits of surface miner are firstly analyzed using the dynamic theory. The rock cutting force is derived based on the rock cutting geometric model. The rock cutting numerical model is built with the finite element software-ABAQUS, and the rock cutting process is simulated by varying the bit’s cutting speed, cutting depth and bit line spacing under the impact of single bit and two synchronization bits. The rock cutting failure laws and the optimization of cutting parameters are analyzed based on the simulation results. The results of this work can be concluded as follows:(1) The bit’s movement of surface miner is the combination of the traction movement of the machine and the rotation movement of the drum. And its motion trajectory is a plane cycloid extending in the direction of traction. The forces of the cutting system (cutting drum and bits) contain its gravity, the thrust applied by the driving system, the torque applied by the rotation driving system and cutting resistance force created after the contact of bits and rock.(2) Under the action of cutting bits, the damage of rock elements is the combination result of tension and compression stress, the rock element is first damaged by tension and then compression, and the volume of rock damaged by compression is larger than tension. The rock contacting with bits are mainly damaged by compression and the rock inside and at surface are mainly damaged by tension. By comparing the rock cutting results of single bit and two synchronization bits, the maximum volume increment percentage of rock damaged by tension is172.5%, and the maximum volume increment percentage of rock damaged by compression is169.9%. The damage area increases60%along cutting direction and56.7% perpendicularly to the cutting direction.(3) Based on the numerical simulation results of bit-rock cutting under the conditions of orthogonal combinations of cutting speed, cutting depth and bit line spacing, the best parameters matching modes with different conditions of certain rock properties are obtained. By synthesizing the above analysis under these three conditions, the optimal matching mode of parameters is that cutting speed is0.45m/s, cutting depth is11cm, and bit line spacing is14cm.According to the above analysis of rock cutting surface miner by numerical simulation, it is helpful to the deeply understanding of rock failure law of surface miner, and can provide a theoretical basis for the development and transformation of domestic similar equipments.更多还原