Large Tonnage Double Rotary Rail Crane Chassis Optimization Design And Research

This thesis analyzes the2888t·m large-tonnage double rotary chassis structure of railway crane by using the finite element analysis software ANSYS. According to the crane’s working conditions, put forward an initial solution, and find out a reasonable computing model corresponding to the actual working conditions by using finite element analysis with different modeling methods in ANSYS,then optimize design, design a lightweight chassis structure, and finally check the stability.The paper firstly gives a brief overview of the development of the railway and the railway crane at home and abroad, and then introduces traditional algorithm and finite element algorithm of the railway crane chassis, and the constraint equation method applied to coupling of units, grids and nodes, connection of plate units and entity units, and the treatment method of the boundary conditions when the oil cylinder and the ground surface contact with each other in finite element analysis of the chassis. This thesis loads variable loads on the supporting of rotary center by using APDL, builds the model by considering chassis, leg, hydraulic cylinder and so on, adopts two different methods of coupling and rigid connection on the joint of the leg and the main body of the chassis respectively, adopts consideration of contact and all degrees of plane freedom constrained respectively,then analyze the effects of different methods’combination on the stress and strain of the chassis. Analyze and check the several dangerous working conditions of the initial solutions. As the raising distance of the chassis leg has influence on the stability and the safety of crane, this paper simulates the actual raising distance of the leg by comparing the leg’s reaction force obtained by theoretical calculation with the one obtained by finite element analysis.The stress and the deformation of the chassis are comparatively small according to the initial design,then the lightweight design of the chassis is considered.Optimize the former four dangerous working conditions of the chassis by using the theory of finite element optimization,after comprehensively considering the rounding of the results,check each working conditions.For the later several conditions that lazy arm rotates in the full plane,check the condition that corner of the lazy arm is perpendicular to the diagonal of the chassis.All check through,and the lightweight design of the chassis is realized.At last,with the continual increasing of the crane’s lifting weight,the structure of the chassis produced in Germany has improved.By adding a longitudinal steel plate girder to the original chassis,the local stress concentration on the variable cross section of the longitudinal beams and joint of the chassis and leg are shared,and the integral rigidity of the chassis is ensured,especially the rigidity around the pivoting support.This guarantees the stability of chassis’s other components.Check on the global stability of the chassis, the flange plate of longitudinal beam and the web plate.On the basis of calculating the stability of the chassis,calculate the critical buckling load by using the linear eigenvalue buckling analysis of the ANSYS,and guarantee the local stability of the chassis.The paper investigated several schemes and finite element analysis methods of the chassis’s design,and optimized the structure of the box-type chassis,proposed a new structure of the big belly beam,and provides much reference value for the later design of the big tonnage double rotary crane of our country.