Optimization experiment on eccentric lapping of cylindrical rollers

Abstract

Cylindrical rollers are important elements of bearings, and their machining accuracy and consistency affect the bearing quality. Using a GCr15 cylindrical roller of Ф11 × 12 as the processing object in this study, the effects of loading pressure, abrasive concentration, and speed combination on cylindrical roller machining precision were investigated using the orthogonal experimental design method on a double-side eccentric pendulum lapping and polishing machine. The machining parameters of the lapping stage were optimized, and the lapping optimal process parameters were determined by S/N response analysis and analysis of variance (ANOVA). The results show that when the experiment was optimized using loading pressure of 10 N/roller, abrasive concentration (3000#Al2O3) of 20.0 wt%, and rotational speed combination, the material removal rate (MRR) of cylindrical roller reached 0.0896 μm/min; the average roughness of the batch decreased from 0.056 μm to 0.027 μm, 51.8% lower than the original batch average roughness, and the deviation decreased from the initial 0.022 μm to 0.014 μm; the batch average roundness error decreased from 0.47 μm to 0.28 μm, 40.4% lower than the original batch average roundness error, and the deviation decreased from the initial 0.19 μm to 0.038 μm; and the batch average diameter variation decreased from 4.5 μm to about 3.6 μm, 20% lower than the original batch average diameter variation. The double-side eccentric lapping of cylinder rollers does not only lead to improvement in the surface quality and shape accuracy of rollers, but also improvement in the batch consistency. Keywords: Cylindrical roller, Eccentric pendulum type, Orthogonal experiment, Lapping, Batch consistency