Evaluation of flow uniformity around automotive pinion gears during quenching∗

Abstract

The use of CFD (Computational Fluid Dynamics) is a powerful engineering analysis tool to reduce distortion, improve yield and to improve “first-time” quality. In this paper, CFD was used to understand quenchant flow in a quench tank, and to understand the effect of quenchant flow on part distortion. FLUENT was used to simulate the quenchant flow through a quench rack of automotive pinions. The analysis showed several locations where the flow could be improved in the quench tank, and identified regions of quenching non-uniformity on the parts. The flow on the parts was examined on the stem, the head and the overall pinion, to identify locations of suspected high distortion.

Techniques and Equipment Types to Harden Gears

“…Models of quenching and factors affecting distortion and residual stress have been previously reported. 2 Free quenching fixtured loads in oil use agitation and baffling to provide uniform quench velocity through the load. Temperature of quenchant is adjusted to minimize distortion while achieving cooling rates to maximize mechanical properties important for gears like bending fatigue and wear resistance.…”

Evolution from Cooling Modeling to Cooling Engineering of the Steel Quenching Process: A Technology Overview

“…While the previous example is a relatively early example of the use of CFD analysis to troubleshoot a poorly performing small quenching system, this methodology is now becoming increasingly common for use in quench system optimization and design. CFD analysis was used to develop optimal racking configuration for a system used for the quenching of carburized AISI 8620 steel pinions by identifying several locations where the flow could be improved and to produce improved hardness uniformity [48]. Chen utilized an ultrasonic Doppler velocimeter to measure the flow rate of quenchant in a large tank with draft-tube agitators.…”

Numerical Analysis of Convective Heat Transfer in Quenching Treatments of Boron Steel under Different Configurations of Immersed Water Jets and Its Effects on Microstructure

“…Various investigations have been conducted to evaluate the cooling medium's effect on fluid dynamics, heat extraction and its effect on phase transformation. Studies [1,2] have been carried out exclusively in fluid dynamics to evaluate the cooling medium's behavior when confined in a quenching tank. In these investigations, only the continuity equations and the Navier-Stokes equations have been solved in conjunction with the turbulence model; B. Hernández Morales et al [1] developed a study of the behavior of hydrodynamics in the quenching of flat-end cylindrical probes subjected to a Jominy-type Fluids 2024, 9, 89 2 of 16 test in order to evaluate the effect of wettability in this type of geometries.…”