Fundamental studies on enhancing heat transfer in contact zone during high efficiency grinding

Abstract

On the basis of research on the thermal effect in grinding contact zone during high effi-ciency grinding, an idea of enhancing heat transfer in contact zone using high pressure water jet impinging is advanced. Fundamental heat transfer experiments on enhancing heat transfer with high pressure water jet impinging were completed. The maximum speed of jet impinging reaches 110m/s. The experimental results of transient and steady-state experiment prove that the critical heat flux and the heat-transfer coefficient of water jet impinging are 70 and 30 times those of the pool boiling, respectively. Furthermore, a new grinding fluid supply system was employed to en-hance heat transfer in grinding zone by high-pressure water jet impingement during creep feed grinding. The experimental results show that high-pressure water jet impinging has remarkable cooling effect. The temperature of the workpiece surface can be steadily kept below 100℃, while the workpiece is badly burnt with conventional coolant supply. The study will exploit an important research orientation that has great potentialities in the high efficiency grinding. Further perfection of this study will not only enable us to increase the available material removal rate to a new level but also solve the workpiece burn problem of the difficult-to-machining materials in high efficiency grinding,