Straight bevel gear cold rotary forging technology and its CAPP system development

Straight bevel gear is common part in mechanical equipments, and it can directly obtain high precision tooth by use of cold precision rotary forging technology. The rotary forging parts have reasonable distribution of metal fiber and its material is strengthened during the process, which not only greatly improve the gear fatigue strength, comprehensive mechanical properties, high dimensional accuracy and surface roughness, but also avoid forging various defects caused by heating. The technology saves energy, materials, reduces processing time, and it can overcome the too large deformation resistance of traditional cold forging and low dies life shortcomings. In this paper, the relationship between rotary forging force and its process parameters, failure modes, material selection, heat treatment and other influencing factors of dies life are researched and the solutions are provided. The CAPP system for forging parts´ parametric design and automatic process cards output is introduced in this paper, developed by SolidWorks2004 as platform and VB6.0 as development language, which greatly reduces labor intensity of technology designers, ensures process standardization, but also the CAD/CAPP integration can be realized through further development.