New system revolutionises hard turning
Currently, hard turning is widely adopted by small- and medium-sized enterprises (SMEs) for producing functional surfaces. However, tools wear after a certain period because of extreme cutting forces and temperatures, and cannot be reused. In such cases, tool replacement is costly, and long set-up times are required. Scientists initiated the EU-funded project EASITAP to develop novel components for longer tool service life and faster set-up. These components were merged into a novel automated production system that integrates hard turning, burnishing and polishing processes. This enables the production of reliable high-precision hardened steel with significantly increased productivity. In particular, scientists developed a high-rotation polishing spindle that can polish complex workpieces together with a polishing tool turret for automatic fast tool exchange. An optical measurement device calibrates a new machine tool directly, measuring the cutting-edge geometry to compensate for potential errors with lathe control. In addition, it provides faster tool set-up. Furthermore, tool deviations in all axes are compensated, since an automated Y-axis — which was hitherto missing — enables fast and reliable adjustment of the tool height. The automated system also includes a hard burnishing tool with diamond tips. Scientists demonstrated that hard burnishing is a powerful finishing process for hard turned workpieces with an 80 % improvement in surface roughness. Finally, they used sensors to measure acoustic emission (sound waves generated by a physical stress) and monitor surface defects. EASITAP novel system should help European SMEs stay afloat as this technology can meet increasing demands for better product quality and variety at lower costs.
Keywords
Automated, hard turning, polishing tool, burnishing, steel, spindle, turret, deviation, sensors, acoustic emission
