液压挖掘机工作装置载荷谱测试方法  

Load Spectrum Test Method of Hydraulic Excavator Working Device

作　　者：向清怡 吕彭民[1] 王斌华[1] 张红 薛璐[2] XIANG Qing-yi LU Peng-min WANG Bin-hua ZHANG Hong XUE Lu(Key Laboratory of Highway Construction Technology and Equipment of Ministry of Education, Chang＇an University, Xi＇an 710064, Shaanxi, China Jiangsu Xuzhou Construction Machinery Research Institute, Xuzhou 221004, Jiangsu, China)

机构地区：[1]长安大学道路施工技术与装备教育部重点实验室,陕西西安710064 [2]江苏徐州工程机械研究院,江苏徐州221004

出　　处：《中国公路学报》2017年第9期151-158,共8页China Journal of Highway and Transport

基　　金："十二五"国家科技支撑计划项目(2015BAF07B02);陕西省科技统筹创新工程重点实验室项目(2014SZS11-P04);陕西省自然科学基础研究计划项目(2017JM5040)

摘　　要：为了给液压挖掘机工作装置的疲劳试验研究提供基础数据,提出了一种能够反映实际作业工况的载荷谱测试方法。该方法以测试截面内力为基础,首先在斗杆无应力集中部位选定测试截面,其次通过布置应变片测量斗杆截面特定测点的应力来拟合斗杆截面内力,通过布置压力传感器和位移传感器同步测量工作装置油缸压力和伸缩量,最后建立力学平衡方程计算出斗尖载荷-时间历程以及工作装置各铰点载荷-时间历程,由载荷-时间历程可求得整机载荷谱和相关零部件的载荷谱。为了验证测试方法的正确性,进行了模拟仿真试验和室内样机加载试验。研究结果表明:斗尖载荷的计算值与仿真值相当吻合,误差在3%以内;斗杆截面特定测点应力的计算值与试验测试值吻合较好,最大平均误差在侧载工况下为3.48%,在正载工况下为6.46%;斗尖载荷的计算值与试验测试值基本一致;该方法得到的载荷谱不仅包含了正载的影响,同时也包含了侧载和偏载的影响,与实际情况更加接近;以截面内力为基础数据获得的载荷谱不受挖掘机细部结构的影响,对吨位相近、斗容量相同的各类挖掘机具有普遍适用性,也可用于其他机械载荷谱测试。To provide fundamental data for the fatigue test of hydraulic excavator working device, a load spectrum test method available to reflect actual operation condition of hydraulic excavator was proposed. Based on the test of the cross-section internal force （CSIF）, the cross-section was firstly selected at the stress-free location of the bucket rod. Second, the CSIF was fitted by placing strain gauges at the specific measuring points of the cross-section, the pressure and the expansion of each cylinder of the working device were synchronously measured by placing pressure sensors and displacement sensors. Finally, the mechanical equilibrium equation was established to calculate the load-time history of bucket tip and each hinge point, and then the load spectrum of the whole machine or the relevant parts could be deduced from the load-time history. The simulation test and the loading test in the laboratory were carried out to verify the correctness of the method. The results show that the calculated values of the bucket tip load are in good agreement with the simulation values, and the error is less than 3%. The calculated stress values of the specific measuring points of the test cross-section are in good agreement with the test values. The maximum average error is 3.48 % under the lateral load, and is 6.46 % under the vertical load. The calculated values of bucket tip load are consistent with the test values. The load spectrum acquired by this method is affected by vertical load, the lateral load and the offset load, which is more close to the actual condition. The load spectrum based on CSIS may not be affected by the detailed structure. It is universally applicable to the other types of excavators with similar capacity, and this method can also be used to test the load spectrum of other machines.

关 键 词：机械工程 载荷谱 应力测试 工作装置 截面内力 

分 类 号：U415.511[交通运输工程—道路与铁道工程]