Investigations of different loading conditions in a high speed mechanical press

At high operating speeds, usually greater than 200 strokes per minute (spm), mechanical presses exhibit dynamic effects that may influence the process conditions. In order to maximize the advantages of high speed presses and maintain reproducible part quality, it is necessary to monitor and understand these dynamic phenomena. To study the behavior of a high-speed press under various loading conditions, a series of experiments was performed with a mechanical high speed press. This press is capable of reaching stroke rates up to 1200 spm. The goal was to simulate several real process loading conditions, by means of calibrated load cells, in order to monitor the dynamic behavior of the press. Changes in shutheight, load, and slide deflection were measured for different press speeds and tonnages. By damping the impact on the load cells, the shape of the load-time curve was made to better represent that of a real process such as blanking. The results of these tests will help to improve understanding, allowing future press applications to be set up faster and more precisely. The information gained from this study will help to improve the practical utilization of high speed presses by (a) improving instrumentation and monitoring techniques, (b) facilitating rapid and precise tool set-up, and (c) incorporating dynamic considerations in process and tool design.