New Models and Global Stability Charts to Avoid Principal Instabilities and Constraints in Throughfeed Centerless Grinding

Abstract

This paper presents new simulation models and global stability charts that have been developed to analyze the principal instabilities and constraints involved in the throughfeed centerless grinding process. In addition to a frequency domain stability analysis of the three characteristic instabilities of the process (geometric lobing, chatter and spinning), new models have been developed and implemented to analyze the other main restrictions, namely, process power, temperature and burning power, roughness, and final part geometrical tolerance due to machine compliance. As a result, new global stability charts have been devised where instabilities are plotted against different productivity rates by combining the two principal variables in the throughfeed process: regulating wheel speed and feed angle. The use of such charts has led to the development of new optimization strategies for throughfeed operation mode and their implementation in a web based SET-UP ASSISTANT software tool developed to improve machining accuracy and productivity in centerless grinding.