大型矿用正铲液压挖掘机挖掘阻力试验研究

Experimental Research on Digging Resistance for Large Hydraulic Face-shovel

为了研究大型矿用正铲液压挖掘机的挖掘阻力,对某70t级的大型矿用正铲液压挖掘机实际正常挖掘作业时动臂、斗杆及铲斗相对于上一级构件的角位移和各个工作液压缸压力进行了现场同步测试。采用MATLAB软件对实测数据进行了处理和曲线拟合,以减小测试过程中的随机因素对计算结果的影响。根据该类型挖掘机的机构特点,以挖掘机工作装置相对角度和液压缸推力为自变量,以切向和法向挖掘阻力为未知数,建立了挖掘阻力的数学模型。根据实测数据,编程计算得出了该挖掘机在实际挖掘过程中破碎介质对斗齿尖产生的切向挖掘阻力、法向挖掘阻力和总挖掘阻力;研究了实际挖掘过程中挖掘阻力的变化情况,论证了法向挖掘阻力与切向挖掘阻力的比值λ的变化规律及相关因素的影响,为正铲液压挖掘机挖掘阻力理论的研究提供了参考。

To study the digging resistance of a large hydraulic face-shovel, the working device＇s attitude （angles） and working cylinders＇ pressure of a 70t-level hydraulic face-shovel was tested synchronously. Moreover, software MATLAB was used in date processing to reduce errors and get general digging performance. Thereafter, by taking the working device＇s angles and hydraulic oil cylinders＇ thrusts as independent variables, and the tangentialnormal digging resistances as unknowns, the mathematic model of the digging resistances was established based on the mechanism property of this type excavator. According to the experimental data and the mathematic model, a program code was made to calculate the tangential resistance, normal resistance and the total digging resistance for the actual digging process. The cutting angle influence on the digging resistance and the ratio of normal and tangential resistance during the actual digging process were studied. The testing and the calculating results provide a precious basic data base for the digging resistance research of the large hydraulic face-shovel and the approach used herein can also be used in the digging resistance research of the similar digging devices.