In-process measurement of form error and force in cylindrical-plunge grinding

This note describes several interesting results obtained from an effort to simultaneously measure grinding force and workpiece form error during cylindrical-plunge grinding. As expected, the measured grinding forces quickly reach a quasi-steady value proportional to infeed rate, spindle speeds, abrasive wheel design, and workpiece material. During this constant-plunge rate grinding, the workpiece form error was found to fluctuate, often over a wide range. Both the frequency content and phase of the grinding force differ from the workpiece diameter indicating that the measured quantities are decoupled from one another. Once the plunge infeed is stopped and the wheel is sparking out, the workpiece form error improves asymptotically for several seconds. The rate of roundness improvement matches theoretical predictions and provides insight into the nature of optimizing workpiece form error.