The Design Of Multi-Objective Optimization Of Main Beam Of 480t Bridge Crane

Bridge crane,as a kind of material handling machinery,is of vital significance in the areas of industrial production.This paper takes 480 t bridge crane as the research object.Design the structure of the key parts in the bridge crane.Analyze the characteristic of the main beam under multi-working conditions by using finite element technology,and make sure that the main beam has a larger lightweight space.The multi-objective topology optimization and the multi-objective size optimization were used for main beam to get the light-weighting model.The main parts of this paper are as follows:(1)Design the overall layout and structure of the 480 t bridge crane according to the actual demand.The designed crane can choose different trolleys according to the weight of materials,including the maximum lifting capacity of 480 t and the auxiliary lifting capacity of 100 t.(2)Analyze the static and dynamic characteristics of the main beam under multiple working conditions to obtain the stiffness and strength characteristics.Get the first 6 natural frequencies and corresponding vibration modes of the main girder through the analysis of the model.The results show that the main girder has a large lightweight space and no resonance.(3)A multi-mode topology optimization method based on the compromise planning method has been proposed.Multi-objective topology optimization has been carried out by taking into account the various operating conditions.According to the optimization results,a new model of the main beam has been established based on the optimization results.Through finite element analysis and comparison,it has found that the stiffness and strength of the main beam are significantly improved and the weight is reduced by 6.028 t,accounting for 9.42%.(4)Based on the results of sensitivity analysis,the optimum design variables has been obtained and a multi-objective optimization mathematical model has been established.The detailed parameters of the optimal structure of the main beam have been obtained through multi-objective optimization.The comparison of finite element analysis shows that the quality of the main beam of the bridge crane is reduced by 2.94% under the condition of basically unchanged stiffness after optimization,and the result of the optimization design is remarkable.