Stress Distribution Test And Fatigue Life Analysis Of Fork Arms Of Scissors Aerial Work Platform

Because of advantages of flexible operation,strong stimulus and locations adaptability,scissors aerial work platform has been widely used in many fields such as construction engineering,sites construction and maintenance,etc.Scissors are the key component of the structure of scissors aerial work platform.With the fastand steady development towards high carrying capacity,scissors carrying capacity has been affected by pulsating load,the problem of structure strength and fatigue has appeared.Taking environment protection and steady safety in to consideration,analysis of scissor stress distribution and its fatigue life research has been greatly important.This paper aims at several key issues of parametric modeling,hydraulic cylinder thrust,analysis of mechanical condition of each hinge hole,static analysis of scissors and fatigue life analysis.It conducts deep research on the scissors by using methods combined theoretical derivation with stimulation analysis,and test the reliability of finite element simulation model via experimental study on stress distribution.The main research contents and results are listed as follows.(1)Based on the principle of virtual displacement,the mathematical model of the fork mechanism is established,the position of the fork mechanism is analyzed,and the thrust of the hydraulic cylinder is calculated.The fork lifting platform at the initial moment is analyzed,the lower fork arm is influenced by parametric relationship of the force of hydraulic cylinder,indicating each hinge hole stress situation of scissors.(2)Based on the finite element analysis software ANSYS Workbench,the three-dimensional solid model of the scissor aerial working platform is established in SolidWorks and transformed into the finite element model.The results show that the maximum stress and the maximum displacement of the fork arm are analyzed by the stress nephogram and displacement nephogram of the internal and external shear fork in order to provide evidence for increase in partial intensity and decline in damage.(3)The test platform of fork arm is set up,and the surface stress value of each hinge hole of the fork arm is monitored according to the need.By comparing the arm stress data obtained from the finite element simulation with the experimental data,the maximum stress of the shear arm is basically consistent,which verifies the correctness of the finite element model.(4)Based on the fatigue cumulative damage theory and average stress correction theory,the fatigue life of scissors arm structure is analyzed,analysis for two conditions,constant amplitude load and variable amplitude load,is made.The life distribution and safety factor nephogram and fatigue sensitivity curve are achieved,analysis of shear fork arm fatigue damage and the position of the maximum structure optimization are conducted.The research results above are applied to the analysis of the product technology of aerial operation platform,which provides a scientific basis for the design of the scissor type aerial work platform.At the same time,it also has some guiding significance for the research and development of the same type of aerial work.