Research On Stamping Forming Technology Of Lower Side Door Frame Of Large Axle Heavy Load Gondola Car

With the rapid development of railway freight car technology in China,high speed and heavy load become the development direction of current and future railway freight car technology.Large Axle Load Gondola car is designed by Zhongche Qiqihar Limited in response to the high-speed,heavy-duty railway freight car demand,is the representative of 80-ton General Gondola car.In view of the problems of the 70-ton General Gondola cars produced at present,which have been put to the test in operation and feedback from the factory,depot repair and manufacturing units,the design structure of the large axle load Gondola cars has been revised and perfected,especially in the position of the door of the side wall structure,the deformation of the lower side door fram e caused by the expansion of the goods is serious,resulting in the lower side door of the side wall is not tightly closed,bulk cargo easy to leak,to the user caused unnecessary losses.In order to improve the anti-deformation strength of the lower side door frame and solve the problem that the lower side door frame can not be closed properly,a new type of lower side door frame structure was designed for the heavy axle Load Gondola car.Compared with the flat structure,the lower side door frame of the ring bar structure can effectively improve the shape rigidity of the door frame and enhance the ability of resisting external deformation.The bottom side door frame is formed by cold stamping of high strength steel plate S450 EW.By consulting a large numbe r of domestic and foreign research materials,the quality control measures of high strength steel plate forming are used for reference,the reasonable forming process of the lower side door frame was worked out.The finite element model of the workpiece is established,and the forming simulation analysis is carried out under different process parameters.The influence of the lower side door frame stamping formability under different process parameters is demonstrated from the aspect of thinning rate and for ming limit,thus,the reasonable stamping forming process parameters are determined.The springback analytic function of the software is analyzed by simulation,and the springback quantity under different conditions is predicted.When the springback is small,the reasonable process parameters are determined and the simulation results are used to compensate the springback.After several times of springback compensation,the dimension of the workpiece is within the tolerance.At this point,the workpiece surf ace is the surface of the mold design.At last,the influence of each factor on the forming quality defect of the lower side door frame is analyzed by orthogonal experiment,and the reasonable value of simulation parameters is determined.