Evaluation of Quality of Steering Systems Using the Honing Process and Surface Response Methodology

Gears are components indispensable in power systems, gearboxes, and machine tools. Modern gears have preferably high strength, high hardness, wear resistance, and low weight. According to this characteristics, the manufacturing process of gear generally use undefined cutting edge. Nowadays, honing process has been introduced in Brazil into companies that manufacturing steering systems and gearboxes. Honing has great advantages that are the possibility of adjustment of gearing failures and mixed orientation of the manufacturing of grooves approaching to the pitch diameter. This paper shows an analysis of honing process that includes a modeling of accurate, the Brazilian development status, and mainly the optimization using response surface methodology. Tests were carried out in plant using 54 pinions of 4320-H steel with hardness of core of 295 HV2 and surface hardness of 600 HV2. The machine used in tests was a Fassler model HMX-400. The input parameters were spindle speed of pinion, speed of grinding wheel, feed rate, spark out, and cycle time. The results showed that the cycle time and feed rate influenced directly the helix form error and the evolvent profile error. The re-sults showed not only on the decrease of surface roughness but also on that, the geo-metric errors were below the standard DIN 5.