| In this paper,the research object is an electric wheel mine truck frame which is from the domestic electric wheel mine truck manufacturer.Combining the theory with practice,the frame is calculated and analyzed for statics and dynamics.The results show that the mechanical properties of static and dynamic characteristics of the frame meet the requirements of structural strength,however,the rear end of the frame beam area exist the problem of excessive local stress in bending and torsion conditions.Through improving the beam parts of the structure,the stress level of the site was effectively reduced.Finally,lightweight design of the frame was implemented in ensuring the strength requirements.The main contents are as follows:(1)An equivalent finite element model of the mine car frame was built by the use of HyperMesh software,of shell elements to simulate the steel frame member,of solid elements to simulate the frame entity member,of spring element to simulate the frame suspension system,of mass element to simulate the mass of each component of the frame and goods.It laid the foundation for subsequent work of statics and dynamics.(2)The static analysis was performed by the use of RADIOSS solver,mainly about the static strength,dynamic strength of five typical working conditions,bending stiffness,torsional stiffness.The results provide a basis for the subsequent structural improvements and lightweight design.(3)The dynamic characteristics of the frame was analyzed.Firstly,it was calculated the frame modal by solving the first frame 100 Hz all modes,and the characteristics of each vibration mode was described.At last,road excitation and engine excitation on the dynamic characteristics of the frame was calculated and analyzed,and the evaluation of dynamic characteristics was made.(4)A partial frame structure improvements and lightweight design of the frame was conducted.First of all,the reason for the stress concentration are discussed,the discussion revealed that the site of stress concentration is due to the stiffness mutation where exist in the connections area of rear end beam and longitudinal beam.The problem of stress concentration sites was effectively solved after the structural improvements made on internal support plate in the rear end beam.Then,the frame lightweight design was implemented by the use of OptiSTruct software combined with the size optimization theory.The mass felled 8.1%after the optimization.And checkingresults has proved that the lightweight frame can meet the strength requirements of the conditions of use.This study not only solve the electric-wheel mining vehicles local stress concentration problems,but also provides a certain reference for the type of mining vehicles lightweight design,It has a certain value in engineering. |
