基于非线性规划的拉斗铲作业平台参数优化

为了提高拉斗铲作业效率,降低倒堆工艺系统生产成本,需要对拉斗铲作业平台参数进行优化。但由于拉斗铲作业平台高度与平台宽度之间相互影响、相互制约,不能对单个参数进行独立优化,而需要以2者为变量,建立优化模型,提出拉斗铲作业平台参数的综合优化方法。为此分析了拉斗铲单向走行、往返走行情况下的挖掘范围,分别推导了各种情况下的拉斗铲挖掘深度、正向及反向走行距离计算公式,提出了拉斗铲走行时间及作业周期的计算方法,建立了拉斗铲生产效率与作业平台高度、作业平台宽度之间的关系模型。利用抛掷爆破爆堆的三维扫描数据,建立平面直角坐标系,拟合得到爆堆曲线方程,进而提出了有效抛掷率、拉斗铲重复倒堆率、辅助剥离率、拉斗铲倒堆率等变量的计算方法,以倒堆工艺系统年剥离总费用最小为目标函数,综合考虑技术、经济、安全3个方面的因素,构建了基于非线性规划的拉斗铲作业平台参数优化模型,并全面分析了作业平台参数的约束条件,包括影响拉斗铲作业安全、高台阶稳定等的作业安全约束,影响拉斗铲倒堆距离、挖掘深度等的拉斗铲线性尺寸约束,以及拉斗铲、辅助设备等的生产能力约束,提出了模型的求解方法。通过计算可知,黑岱沟露天煤矿的拉斗铲作业效率随着作业平台高度、作业平台宽度的增大先增大后降低,作业平台高度为13.30 m,宽度为118.10 m时,拉斗铲作业效率最大,为4 043.02 m~3/h;其最优作业平台高度为14.60 m,作业平台宽度为118.00 m,优化后每年可节省剥离费用371.70万元。

Parameters optimization of dragline working platform based on nonlinear programming

To improve the production efficiency of dragline and reduce the production costs of dragline operation,the parameters of dragline working platform should be optimized.However,due to the interaction of the weights and heights of dragline working platform,individual parameters cannot be optimized independently.Thus,the optimization model taking them as variables should be established,and the comprehensive optimization method for the parameters of dragline working platform should be proposed.Therefore,the dragline digging ranges in the situations of one way and round trip operation were analyzed.The calculating formulas of digging depth under varying conditions,and forward and reverse walking distance were deduced,the calculation methods of dragline walking time and working cycle were presented,and the relationships between the heights of dragline working platform,its weights and dragline production efficiency were built.In addition,the curve equation of muck pile profile was fitted on the planar cartesian coordinate system based on the three dimensional laser scanning data of casting blast muck pile,and thus the computation methods of the effective throw rate,duplicate stripping rate of dragline,auxiliary stripping rate,dragline stripping rate were proposed.By taking the minimum stripping cost of dragline stripping system as objective function,the model for optimizing dragline working platform parameters based on non linear programming was established in comprehensive consideration of the technical,economic and security factors.The constraint conditions of working bench parameters were analyzed comprehensively,including the safety constraints affecting dragline operation and safety of high bench stability,the dragline line specifications constraints concerning the dragline stripping distance and digging depth,and the production capacity limit of dragline and auxiliary equipment.Finally,the solving method of the model was put forward.The study of Heidaigou surface coal mine shows that the production efficiency of dragline increases at first and then decreases with the increase of weights and heights of dragline working platform.When the working platform height is 13.30 m,and working bench weight is 118.10 m,the production efficiency of dragline is the biggest,which is 4 043.02 m3/h.The optimum working bench weight and height are 118.00 m,and 14.60 m respectively,which will save the production costs of dragline stripping system at 3.717 0 million Chinese yuan a year.