Numerical Simulation Research On Stamp Forming Of Railway Vehicle Body Part

The technology of railway vehicle is the main factor that constraints the development of city trafficking. Railway trafficking is the backbone industry in our country. With the quick development of modern traffic and increasingly drastic market competition, the manufacture of railway vehicle requires much more about esthetic appearance , comfort and high quality ,so the requirement of stamp forming quality and precision in body part needs more improvement. The stamp forming simulation technology of body part in orbit vehicle is the research area of inter discipline including metal plastic forming theory and process, computational mechanics, CAD technology, computer graphics, etc. It is a very benefitial project because it makes engineering testing times of new product decrease , thus it shortens the development cycle of the new product and lowers the cost of the new product. Nowadays, developed countries have put the technology of simulation in practice during production design and manufacture, but in our industry it is just at the beginning.The article performs the simulation of the forming of railway vehicle body part side pillar by using DYNAFORM software, probable defects during the side pillar forming are discovered and summarized .Aiming at the defects during the side pillar forming , such as section opening , side wing drooping , longitudinal buckle and so on , we make a analyses of influencing factor including blank holding force , die clearance , punch angle radius and press of top board , find the cause of forming defects , and put forward the rational processing plan by optimizing the forming processing parameters . The main contents and results are as follows:(1) Numerical simulation and analyses aiming at the defects during side pillar forming ,such as section opening and side wings drooping .Blank holding force is the main factor that influences section opening and side wings drooping . The increase of blank holding force can effectively reduce the section opening and side wings drooping , however ,when the blank holding force reach a certain degree , the trend of defects reducing inclines to calm . The die clearance makes certain effects on forming defects , the larger die clearance is , the more apparent the springback is . If we want to control the springback ,we must choose the right and small die clearance . Punch angle radius also make great effects on springback , the springback is small when the punch angle radius is also small , we can control the defects at range of deviation.(2) Numerical simulation and analyses aiming at the longitudinal buckle defect during side pillar formingLongitudinal buckle defect are easily generated during the side pillar forming . Blank holding force is the main factor of controlling longitudinal buckle. Longitudinal buckle value can be effectively reduced by increasing blank holding force ,with an aid of increasing the press of top board ,the buckle value can be controlled at range of deviation , the defect of large longitudinal buckle value are solved.(3) The experimental research and processing plan presentingBy numerical simulation and analyses aiming at the defects during side pillar forming , the article puts forward the processing plan ,besides , proves the rationality of the parameters by correlative experimental research , and presents the processing plan of side pillar forming , which is that the side pillar should be formed under the condition of large blank holding force ,small die clearance and punch angle radius , with an aid of increasing the press of top board meantime , which can make the part forming at the favorable sustain .(4) Practical application in the industry productionThe article make the processing plan which is obtained by numerical simulation and experimental research apply to industry production . During the stamp forming production of side pillar of No13 subway vehicle in beijing , the side pillars with high forming quality and good precision are obtained , and have already been applied to mass production.Based on the numerical simulation and analyses of defects during the side pillar forming , Parameter optimization and numerical simulation were proved to be correct and the results can be used to direct the practical production. The article solved the practical problem , filled the blank of the enterprise , and illustrated the validity and the feasibility of numerical simulation of stamp forming.This accumulate precious experience for the further study and spread , and supply spacious space for application in numerical simulation techniques.