Large Impact Type Mobile Crushing Station Fatigue Analysis Of The Main Frame

In recent years,with the increasing volume of open-pit mining,the traditional mining technology has caused a great waste of cost.Then the mobile station has been used more and more widely because they can move to any mining position.As the main bearing mechanism of mobile crushing station,the main frame must has enough strength,stiffness,vibration and fatigue performance to ensure the safety,operational stability and service life,and so on.Therefore,the research on characteristics of the main frame of the mobile crushing station plays an important role in the design of the mobile crushing station and it has great economic and safety significance.In this paper,the main frame of the large impact mobile crushing station is studied mainly.Based on the finite element software and fatigue simulation software,we mainly analyse the static,dynamic and fatigue failure of the main frame of the large impact mobile crushing station.The main research contents are as follows:Firstly,the stress analysis of the main frame is carried out under the typical working conditions,then static analysis of the main frame is carried out to obtain stress and displacement distribution nephogram by using the ANSYS software.Observe and analyze the results to determine the strength and stiffness of the frame to meet the requirements.Sufficient strength and rigidity are two prerequisites for fatigue life,if which can not meet demand,structure improvement must be put on the frame.Secondly,dynamic characteristic analysis of the main frame is carried out,modal analysis and transient dynamic analysis included.In order to prevent resonance,the modal analysis of the main frame is implemented to obtain the natural frequency and mode of vibration.Through the analysis and calculation of the impact force and vibration force on the main frame,the force that has the greatest influence on the vibration characteristics of the frame is obtained.On the basis of the above work,transient dynamic analysis of the main frame is carried out,the dynamic response of the most dangerous part is obtained.Finally,selecting stress-time history on the most dangerous part in transient dynamics analysis as source data,which is dealt with the rain flow counting method for compilingthe load spectrum of the main frame of the crushing station with random vibration under typical working conditions.The material parameters are calculated by empirical formula,which are used to obtain the S-N curve of the material in ANSYS Ncode Designlife.By analyzing the factors that affect the fatigue life curve,the transformation from the S-N curve of the material to the S-N curve of the zero component is completed.And by making the integration of the dynamic response,load spectrum and S-N curve of the completed frame,fatigue analysis and life prediction of the frame are provided for the design of the main frame.