This paper provides an overview of the key roles that centerless grinding technology has played in the industry for about a century. The radical evolution of centerless grinding technology has been made with the help of deep understanding of the process and main critical features. It took over three quarters of a century to accumulate today's knowledge of centerless grinding theory. The R&D community, especially CIRP STC-G, has made a significant contribution to the evolution of centerless grinding technology. This paper describes today's understanding of the theory as well as the design of critical elements of the machine, and provides guidelines for the design of future machines. Furthermore, the paper discusses state-of-the-art centerless grinding machines and their applications as well as advanced monitoring systems, pointing the way for machine development and research work. The performance of centerless grinding machines has been improving in response to strong demands in accuracy and productivity from mass-production industries, especially, automotive and bearing. The demands will become much tighter and higher in the future as shown. In addition, the future centerless grinding machine will be required to satisfy new demands from the modern lean manufacturing system. These demands are to improve the flexibility of centerless grinding, in other words, quick changeover, lower tooling complexity and minimum inventory management with small lot size production. In order to provide technical solutions, the following topics in research and development should be considered: Development of an ultra-precision and super high stiffness centerless grinding machine. This machine will be required to achieve the roundness of 10 nm order and the throughfeed rate of 10 m/min. Development of a highly flexible centerless grinding machine. Changeover time of less than 15 min is required without part specific tooling, where the changeover time is defined as the time from last good part to new good part. Development of a combination centerless grinding machine: The examples are OD/ID or OD/face simultaneous centerless grinding machine. By combining OD/ID grinding operation, the wall thickness variation of the ring will be drastically reduced, and by combining OD/face, the squareness of the part will be improved. Both machines have a potential to solve current serious problems facing in industry. Development of a centerless grinding method for ultra-small components: The centerless grinding method provides the solution for holding ultra-small parts for finishing. This machine will be applied in micro-component manufacturing, such as biomedical parts. Development of a continuous centerless grinding for profiled components: Today the infeed method is used, but the productivity is much lower than the throughfeed method. This is a requirement of high efficiency centerless grinding. An advanced tangential feed method can be considered. Development of a highly integrated intelligent centerless grinding machine: The intelligent management tool will have the capability of setting up the optimum grinding conditions and providing the virtual grinding simulation, optimum grinding cycle design and self-adjustment with advanced process monitoring systems.
Advances in centerless grinding technology
2012
24 Seiten, 60 Bilder, 2 Tabellen, 148 Quellen
Conference paper
English