Study On The Technology Of Precision Forming For Spur Gear With Big Modulus

Spur gears with big modulus are key parts applied widely in the automobile and heavy mechanical industry. The quality and life of the spur gears directly affect the whole machine of the technical and economic indicators. Developing a new forming technology to substitute for conventional cutting process, minimize energy consumption, improve material utilization rate and product quality, and reduce production costs is an important issue for Plastic processing industry in our country.In the paper, the study on the warm-cold composite precision forming process of low-alloy steel spue gear was carried out by means of FEA and experiments together with the related process and die was developed successfully.The structure and shape features of the spur gear with big modulus were analyzed in detail. To improve the dimensional accuracy, surface quality and die life in spur gear forming, a two-step forming process scheme including warm-forging preforming and cold precision sizing was proposed and the process plan was woked out. A three-dimensional rigid-viscoplastic finite element for warm forging preforming and a three-dimensional elasto-plastic finite element model for cold sizing of spur gear were established. Furthermore, forming process was simulated to achieve optimum process parameters using Deform-3D.The variation laws of sizing amount and relative thickness on springback was obtained and optimized of sizing amount on the gear surface in the performing processBased on the processing analysis and the simulation, the die of the warm-forging preforming and cold precision sizing for spur gears were designed. Corresponding experiments were carried out and the results verified the simulating result of warm-cold composite precision forming process. The study has significance to the practical application of spur gear with big modulus.