Study On Forming Process Of Heavy Automobile Front Axle

Heavy automobile front axles are important forgings of motorbuses and heavy trucksunder high load. They are difficult to forge, because of complicated shapes, deep, narrowand ups and downs larger sections. According to analyse the automobile front axle formingtechnology at home and abroad, the author decides to adopt China’s independent researchand development process of precision roll forging-die forging forming to forge heavyautomobile front axle. This process has many advantages, such as, good adaptability, highautomation degree and less investment.The process of heavy automobile front axles precision roll forging-die forgingforming and die design have no precise forging theory to guide, and mainly depend on theexperience and mechanical design handbooks. So it needs to modify design parametersrepeatedly, and it is not only very difficult to achieve by hand, but also requiresconsiderable manpower and resources. With the development of plastic forming theory incomputer application, the finite element method simulation technology begins to be used inlarge to assist mold design. Through the finite element method simulation, the problemsmet during the plastic forming process being finded and solved, and the situation of metalflow, the mould load, the temperature field and equivalent stress and strain field in plasticforming process can be predicted, with the processing parameters and mould structure canbe optimized,. So the development design cycle and the cost of the process and dies can bereduced.This paper, according to a type of heavy automobile front axles forging drawingoffered by the factory, designs the precision roll forging-die forging forming process andthe die. The process consists of roll forging forming, bending forming and whole finishforging. Analyse and solve the technical difficulties in the forming process, the technicaldifficulties met mainly include the elongation distribution of different steps, the lengthcontrol of roller forgings, the longitudinal meshing of blank and mould groove and how toobtain large broadsiding in roll forging forming process. UG software is used to realize3Dparametric modeling of roll forging forming die. It is necessary to ensure roll forgingforming die characteristic structure parametric, with the purpose to modify roll forgingforming die structure according to the finite element simulation results. The dies ofbending forming and whole finish forging processes are designed by the method of general 3D modeling.The three dimensional thermo-mechanical coupled simulation of the heavyautomobile front axles precision roll forging-die forging forming process is carried out byusing the finite element method simulation software DEFORM-3D to analyse and solve theproblems encountered in the forming process. The problems that may occur in roll forgingforming is how to solve the swing motion caused by non-uniform deformation, the seriousdistortion of spring seat and the lag and advanced phenomenon appeared in part of theblank and roller forming die, in addition, it should be pay attention that if the blankbending degree does not reach the set value in bending forming, the forming quality offorgings will be influenced in the whole finish forging process.The article optimizes the technological parameter and die structure of heavyautomobile front axle precision roll forging-die forging forming technology based on thefinite element method simulation results. In the end, analyse the situation of metal flow,the mould load, the roll forging torque, the temperature field and equivalent stress andstrain field in whole forming process to provide the theory basis and guidance to actualproduction of the heavy automobile front axle precision roll forging-die forging formingprocess, die design and equipment selection.