Continuous variable feed rate: a novel method for improving infeed grinding processes

This paper presents a novel method for improving infeed grinding processes based on the application of continuous variable feed rate (CVFR). Nowadays, infeed cycle configuration is defined by selecting constant feed rates and stock removals for each consecutive stage, normally roughing, finishing, and a final spark-out, for the purpose of achieving required workpiece tolerances in a fixed time while avoiding process limitations and instabilities. CVFR leads to more efficient cycles without the difficulty of defining feed rate and stock removal values. To that end, CVFR has been implemented in a time-domain simulation of infeed grinding processes to analyze theoretically the influence of variation parameters in process forces, workpiece roughness, roundness and size tolerance, or dynamic behavior. Then, tests have been performed to validate the simulation approach, comparing CVFR cycles with equivalent conventional ones. Different types of downward variations for the feed rate have been applied, concluding that grinding processes can be improved with this method regarding productivity and workpiece geometrical and surface tolerances.