液压挖掘机动臂疲劳台架试验方法研究

发布时间：2018-06-02 07:01

本文选题：挖掘机 + 动臂　；参考：《长安大学》2017年硕士论文

【摘要】：挖掘机作为目前世界上使用最广泛的工程类机械之一,面对的市场十分巨大。由于挖掘机工作环境恶劣,工作装置承受的载荷复杂多变,导致其结构发生失效的主要原因是疲劳损伤累积引起的疲劳裂纹及疲劳断裂。动臂在挖掘机工作时承受的载荷情况通常是最为恶劣的,所以对挖掘机动臂进行疲劳可靠性研究,对于改善动臂结构,提升挖掘机的工作性能、工作效率和可靠性具有重要的意义。针对以上问题,本文设计了一种应用于挖掘机动臂的疲劳可靠性台架试验方案。本文以山河智能SWE350型挖掘机作为研究对象,针对挖掘机动臂最大负载的典型工况进行受力分析,计算得出挖掘机工作装置的受力情况。通过对铲斗与斗杆铰接处销轴、斗杆与动臂铰接处销轴、连杆的载荷计算,为销轴传感器的设计、试验装置和方法制定提供了初始数据。根据受力分析结果,提出了两种挖掘机动臂疲劳试验载荷谱测试方案。该测试方法通过设计专门的销轴传感器和连杆传感器,对工作装置载荷进行测试,最终得出动臂铰点的实际受力情况,为后期对动臂进行疲劳试验提供了实际加载数据。在现有设备基础上,提出了动臂疲劳台架试验的加载方案,并完成试验工装的设计和强度计算。该试验方案具有试验载荷自平衡的特点,可以将试验载荷由试验装置内部承受,极大地减弱了试验进行时设备振动对周围环境的影响。最后,建立动臂疲劳试验加载方案的三维模型,并对该模型进行有限元静力学分析和模态分析。根据分析结果,对各部件结构设计进行优化,保证所设计的试验装置静力学、动力学性能均能满足试验要求。
[Abstract]:As one of the most widely used engineering machines in the world, excavators face a huge market. Because the working environment of excavator is bad and the load on the working device is complex and changeable, the main cause of structural failure is fatigue crack and fatigue fracture caused by fatigue damage accumulation. The working load of the arm is usually the worst, so the fatigue reliability of the arm of the excavator is studied to improve the structure of the arm and improve the working performance of the excavator. Efficiency and reliability are of great significance. In view of the above problems, a fatigue reliability test scheme for excavator arm is designed in this paper. This paper takes Shanhe Intelligent SWE350 excavator as the research object, analyzes the typical working condition of the maximum load of the excavator arm, and calculates the force situation of the excavator's working device. The initial data are provided for the design, test device and method of pin sensor through the calculation of the pin shaft at the hinge joint of bucket and bucket rod, the pin shaft at the hinge of bucket rod and moving arm, and the connecting rod. According to the results of stress analysis, two kinds of load spectrum test schemes of excavator arm fatigue test are put forward. By designing a special pin shaft sensor and a connecting rod sensor, the load of the working device is tested, and the actual force of the arm hinge point is finally obtained, which provides the actual loading data for the fatigue test of the arm in the later stage. On the basis of the existing equipment, the loading scheme of the movable arm fatigue bench test is put forward, and the design and strength calculation of the test equipment are completed. The test scheme has the characteristic of self-balancing of the test load, which can bear the test load from the inside of the test device, which greatly reduces the influence of the vibration of the equipment on the surrounding environment when the test is going on. Finally, the three-dimensional model of the loading scheme of the moving arm fatigue test is established, and the finite element statics analysis and modal analysis of the model are carried out. According to the analysis results, the structural design of each component is optimized to ensure that the static and dynamic properties of the designed test device can meet the test requirements.
【学位授予单位】：长安大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TU621

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