This investigation deals with the fluid-dynamic behavior of the hardening process for change-speed gears, where a Nitrogen high pressure flow is used for quenching. At the end of the process, the gears showed a high planarity error due to a slow and non-homogeneous cooling process. A detailed fluid-dynamic calculation was performed to identify some possible technical improvements, such as varying some design parameters including the geometry configuration of the quenching chamber and the operating conditions. Three performance indexes have been defined to synthesize the quality of the hardening process and their trends have been evaluated as a function of the design and operative configuration by a DOE–ANOVA statistical analysis to obtain the best configuration.

Issue Section:
Heat Transfer in Manufacturing
Keywords:
optimisation, computational fluid dynamics, quench hardening, variable speed gear, statistical analysis, forced convection, surface hardening, Forced Convection, Heat Transfer, Modeling, Processing, Unsteady
Topics:
Cooling, Design, Gears, Quenching (Metalworking), Hardening, Errors, Optimization, Fluids, Temperature
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