Title

Workpiece shape control in through-feed centerless grinding

Date of Completion

January 1998

Keywords

Engineering, Mechanical

Degree

Ph.D.

Abstract

Through-feed centerless grinding is a precision finishing process used to manufacture circular components. This dissertation investigates the workpiece shape generating mechanism in the through-feed centerless grinding process. Specifically, the workpiece lobing mechanism and axial guidance through the grinding gap were studied.^ To study the workpiece lobing mechanism, a computer simulation of the plunge centerless grinding process was developed. This simulation was experimentally verified by comparing the harmonic spectra of simulated workpieces with the spectra of workpieces ground with similar set-up parameters. The simulation correctly predicted which frequencies on the workpiece surface were more susceptible to roundness errors than others. These results were found to also be compatible with a previous linear lobing model (ZHOU 94). The plunge lobing analysis was then extended to the through-feed case by means of an average growth rate chart. This chart characterizes the workpiece lobing stability for a given through-feed set-up. Again, experimental studies were conducted to verify the accuracy of this model and it was determined that the average growth rate chart was effective in assessing the workpiece lobing stability for the case of short workpieces like bearing rings.^ To address the problem of controlling the workpiece cylindrical form, a simulation of the workpiece supporting system was developed. These results confirmed the accuracy of previous researcher's analytical estimates of the proper regulating wheel shape. It was also proposed to use this type of simulation as an objective function to optimize the workpiece guidance system for specific applications. ^