Forging Process Optimization Of Heavy Truck Front Axle Based On Numerical Simulation

The front axle of heavy truck bears a great load on the truck,which requires greater strength and stiffness,and it is difficult to forge because of its complex shape and large section variation.At present,there are two main forming methods for the front axle of heavy truck at home and abroad.The first one is the production process of rolling forging,bending,pre-forging and final forging.The production process has high efficiency,good quality of forgings and good working conditions.But the tonnage requirement of the equipment is high and the investment is large.The second is the production process of precision roll forging,bending and plastic forming.The production process generally adopts 3 or 4 passes of precision roll forging and direct forming,which requires less tonnage of equipment and less investment.But the production efficiency is low and the process stability is poor.In this paper,the preforming roll forging + die forging forming process is adopted.In the preforming roll forging process,the spring base parts are basically formed,the I-beam and fist parts are square,and the forgings formed after the roll forging are finally formed by pressing bending,pre-forging and final forging forming processes.Through the preforming roll forging,the deformation of the material is reasonably distributed,the wear of the pre forging and final forging die on the large deformation part of the spring base is reduced,the service life of the die is increased correspondently,and the production cost is reduced.At the same time,the cavity size and billet volume are controlled precisely by numerical simulation,and the utilization rate of the material is improved.In this paper,according to the heavy duty truck front axle forging drawing provided by the enterprise and the existing equipment conditions of the enterprise,the two-pass pre-forming roll forging process is determined by calculation.The forging diagram and characteristic cross section of each pass roll forging were designed,and the three-dimensional parametric modeling of each pass roll forging model was completed by UG software.According to the contour of the characteristic section of each pass,the groove of the roll forging die is designed,the reasonable forward slip value is selected,the central Angle corresponding to the arc length of each characteristic position is calculated,and finally,the three-dimensional parametric modeling of the roll forging die is carried out with UG software.The bending die is modeled by conventional 3D modeling method.The established models of blank,roll forging sequence,roll forging die,bending,pre forging and final forging die were imported into DEFORM-3D software.through the finite element numerical simulation,gained the pre forming roll forging process for different flow of metal,the equivalent stress and strain field distribution,the distribution of temperature field,mold the change of load,such as information,Through the analysis of the defects in the roll forging process,the structure of the roll forging die is optimized,and the forgings that meet the requirements are obtained.Orthogonal experiment was designed to optimize the process parameters,and the radius of fillet corner of spring seat,roll forging angular velocity,friction coefficient and initial temperature were selected as influencing factors,and the evaluation index was the maximum forming load.A group of optimal parameter combinations were selected by range method,and the optimal parameter combinations were simulated by Deform-3D.The results were in line with expectations.Compared with the existing process simulation results,the load of die forging is reduced,the utilization rate of materials and the service life of die forging die are improved,and the production cost of the enterprise is reduced.