Research On Cylindrical Gear Forming By Rolling Technology

Cylindrical gear is an important gear type of mechanical transmission,which is widely used in many fields,such as vehicles,ships,wind power,petrochemical industries,etc.At present,the main methods of cylindrical gear forming are cutting and forging technology.The cutting method is used widely,but the disadvantages is also obvious,such as low efficiency and utilization rate of material and high energy consumption.Comparing with the cutting method,the forging technology can improve the production efficiency and utilization rate of material and decrease the energy consumption.However,as an integral forming method,the forming force of forging technology is large and the service life of die is low.The precision rolling technology is a kind of continuous and local plastic forming process and has some advantages in many aspects,such as reducing the forming force and equipment tonnage,smaller vibration impact,saving resource,etc.In order to realize the application of cylindrical gear forming by rolling technology,the forming laws have been studied through theoretical analysis and finite element simulation in this paper.The main research contents are as follows:(1)The FE model of spur cylindrical gear forming by rolling technology is established.According to the principle of upper limit method,the theoretical formulas of rolling force are figured out and the reliability of formulas is proved by comparing the results of finite element simulation.Meanwhile,the FE model of spur cylindrical gear forging is founded and the simulation results is used to prove the advantage of rolling technology in reducing the forming force.(2)The FE model of spur cylindrical gear forming by rolling technology is founded.The metal flow,effective strain field,velocity field,axial increase rate and rolling force are analyzed during rolling process.Meanwhile,the forming results with different technological parameters are studied,such as feed of each rotation,geometric dimension of billet and idle roll,friction coefficient.And the influence laws are analyzed.(3)The FE model of helical cylindrical gear forming by rolling technology is founded.The metal flow,effective strain field,velocity field,axial increase rate and rolling force are analyzed.Meanwhile,the forming results with different technological parameters are studied and the influence laws are concluded.