Excavator Work Device Of The Crushing Operation Dynamic Characteristics And Fatigue Analysis

Apart from bucket, excavator can equip different working devices,hydraulic hammer is one of them. The breaking working condition of excavatoris wildly used in practical production. It improves work efficiency and laborsafety greatly. Because of its working Characteristic，the working device ofexcavator generates failure with the severely shock vibration, such as resonance,structural deformation, fatigue wear and so on. A lot of research is done byrelated scientific personnel, however, most of them don’t analyze the wholeworking device but the single member such as boom or arm. This thesis dosedynamic characteristics research for the whole excavator working device, whichcan provide references and basis for frequency matching of excavator andhammer, structural optimization and prolonging working device’s fatigue life.The contents of the thesis are as follows:(1) Firstly, this paper introduces the excavator’s industry Overview and thedifferent working device of excavator, then debating the research status ofexcavator working device, after that, summarize the research status of excavatorworking device, aiming at which the objective and significance of this paper areproposed and the research content is also proposed.(2) Analyse the superior performance and the problems of excavator’sworking device equipped hydraulic hammer in practical operation, createvibration differential equation of working device. According to related model,the three-dimensional model of excavator working device was created.Regulation of each hydraulic cylinder’s length obtained three typical workingconditions. Connect ANSYS Workbench and Pro/E Seamlessly. Import thethree-dimensional model into Workbench. Create the finite element analysismodel of three working conditions, through grid division and boundaryconditions setting.(3) Obtain the natural frequency and vibration mode of the working deviceof three working conditions, throng multi-rigid-body modal analysis and fluid-solid coupling modal analysis. Contrast the result and learn the workingdevice’s modal comprehensively, which provides references for the frequencymatching of excavator and hammer.(4) Selecting three key parts of working device make harmonic responseanalysis for working devices of three working conditions. Obtain displacementresponse curve of the frequency of working device key sites. Analyze theamplitude-frequency characteristic of structure key sites. The result validates theresonance effect, fatigue load and other Dynamic characteristics for workingdevice.(5) Create the S-N curve of excavator working device in Workbenchmaterial library. Make finite element fatigue analysis of working device of threeworking conditions. Obtain the minimum fatigue life， the positions thatminimum fatigue life occur, the areas that fatigue failure happen easily. Theresult provides references for working device structural optimization andprolonging working device’s fatigue life.