The Optimal Design And Welding Simulation Of Bridge Crane's Box Girder

Lifting machinery is essential for modern production as means of transport. The domestic bridge cranes'structure sizes are generally larger than the foreign products with the same model and the same tonnage. In addition to the difference of materials, the structural differences in size are the main reason. To reduce material waste, the studies of girder's structure analysis and optimal design are proposed.The girder of crane is a structure of welded steel, whose welding process accounts for a large proportion in manufacturing process. If welding process programming is unreasonable, welding residual strain may lead to inadequate camber, or even cause the deflection, which will affect the safe operation of cranes seriously, and lead to the personal and property safety hazard. So the welding process is studied and the effect of the welding parameters on the deflection of crane girder is analyzed by numerical simulation.In the condition of certain weight and span of bridge crane's girder, ANSYS finite element analysis software for structural analysis and procedures to optimize the design of girder are adopted. In order to achieve the least consumables under the premise of meeting the strength and stiffness, a optimal design result is obtained. It is lightened by 27 percent; Then, the welding of L-plate is simulated by moving segmented heat source model and adopting coupled thermo-mechanical and life and death cell technology, which is verified through experimental study. According to the optimized size, the model of crane's girder is established to simulated the welding of lap and web of girder. The affect of welding sequence on the deflection is analyzed and comparison of theoretical calculations is carried out, which is a valuable guide for the pre-camber when the web is cut.