Numerical Simulation Research On Subway Wheel Rotary Forging Process

The subway wheel takes on the role of bearing the weight of the subway,bearing all the static and dynamic loads,transferring the driving force and braking force,absorbing friction heat and heat dissipation,ensuring that the train runs and turns in orbit.It is an important part of the subway vehicle.Due to the eccentric and the low precision of wheel size,wheel formed by the traditional swaging-rolling process,have the defects of heavy eccentricity,shape,and low dimensional accuracy,so that the vehicle is out of balance,the roughness of the cabin is increased,and additional couple force is added to reduce the service life of the axle shaft.With the development of transportation to heavy load and high speed,it is urgent to study the new process of wheel forming to improve the quality of wheel products.Rotary forging is a kind of processing technology suitable for plastic forming of plate parts.It has the advantages of small forming force,high quality of product and low noise.It has been applied in the production process of traditional railway vehicle wheels abroad,and it has obtained good quality wheel products.Based on the actual production requirements of the wheel company of MaGang,the paper studies the subway wheel swaging-rolling technology.With the help of DEFORM software platform,this paper conducts a numerical simulation study on the rotary forging process of the subway wheel,discusses the feasibility of the wheel rotary forging,the shape of the blank and the influence of the main technological parameters,and provides the basis for the actual production of the wheel and the mold design.According to the material and shape structure of the SH840 subway wheel,the paper has formulated the "upsetting-punching-rotary forging" and "hydraulic press preform-punching-rotary forging,two kinds of forming process.And the topic designs three kinds of the hole plate and the thin blank at the wheel disk,and the three kinds of hole plates and the thin blank at the wheel disk forming process is simulated and comparative analysis.The results show that the hole plate is easy to swing and skew in the forming process,which leads to waste products.The thin blank at the wheel disk(I-shaped blank)as wheel rotary forging reduction billet is more reasonable,and the shape design is more advantageous to the metal flow in the cavity.The formed parts have a great quality of flow distribution and high precision of shape and size.Based on optimizing the blank,this paper simulates the rotary forging process under different technological parameters.The influences of the angle of the pendulum,the feed speed and the initial forging temperature on the forming load,the temperature field distribution,the deformation uniformity of the formed parts and the stress distribution are discussed.It shows that increasing the initial forging temperature,the forming load can be reduced,the deformation uniformity can be improved,and the quality of formed parts is improved.Therefore,the initial forging temperature of the workpiece should be improved as far as possible in the range of material hot forging temperature.Increasing feed speed,the forming efficiency can be improved,and the temperature drop of the workpiece is reduced,and the temperature distribution is not uniform,so the deformation of the formed part is more uniform.Increasing the angle of the pendulum,the forming load is significantly reduced,but the deformation of the workpiece is also increased,which affects the quality of the formed part.By using the maximum forming load and the equivalent strain difference to optimize the orthogonal test,the optimal rolling process parameter combination was obtained.Parameter combination is the initial forging temperature T=1150?,the angle of the pendulum ?=6°,and the feed speed v=6 mm/s.The results show that the forming load is reduced,and the deformation uniformity is improved.