液压挖掘机工作装置的应力特性及危险工况选取

Stress Characteristic of Working Attachment of Hydraulic Excavator and Selection of Dangerous Working Conditions

液压挖掘机工作装置采用传统分级方法对结构进行分析时,一个齿尖位置只能对应一个姿态,因而产生分析不全面的问题.为此,将工作装置作为整体进行研究,提出一种基于区域规划的三维图谱(MBRS-3D)法来探究工作装置的结构特性,并以应力特性为例展开分析.通过测试、统计得到挖掘阻力系数和阻力矩系数,建立理论挖掘力求解模型.基于工作装置区域规划对工作装置进行集成有限元分析,得到动臂、斗杆、铲斗和整个工作装置的最大应力值以及对应区域编号;绘制三维最大应力空间图谱和对应的区域空间图谱,直观呈现最大应力值以及所在区域的空间分布.最后,基于上述应力研究选取某机型的危险工况,并与经典工况进行对比.结果表明,新危险工况比经典工况更具危险性.

When the structure of the working attachment of hydraulic excavators classification method,one tip position of buckets only corresponds to one attitude.Therefore,the analysis is incomplete.In order to solve this problem,by taking the working attachment as a whole,a method(MBRS-3D)of 3D atlas of the maximum stress and corresponding stress atlas based on a the structural characteristics of the hydraulic excavator attachment,and the maximum stress is taken as an example to conduct an analysis.Then,the excavation resistance coefficient and the resistance moment coefficient are acquired by testing and statistics,and a calculation model of the theoretical digging force is constructed.Based on the regional planning of the working attachment with variable parameters,an integrated finite element analysis of the working attachment is implemented,thus obtaining the maximum stress values and the corresponding of the boom,the stick,the bucket and the whole excavator attchment.Afterwards,the 3D atlas of the maximum stress and the corresponding region are drawn to visually describe the maximum stress value Finally,the dangerous working condition is selected through the proposed method,and it is compared with the classic condition.The results show that the selected dangerous working condition is more dangerous than the classic one.