High Efficiency Deep Grinding, an Application with conventional wheels

The recently emerged High Efficiency Deep Grinding (HEDG) allows the grinding process to be undertaken at high wheel speed, relatively large depth of cut and moderately high work speed. HEDG, whilst combining the mechanics of high-speed and creep feed grinding, offers the possibility of achieving very efficient grinding with values of specific energy approaching those of conventional cutting processes. HEDG requires a high power input and consequently needs a well-designed process to secure the work piece surface integrity, low temperature, and a reduced wear of the grinding wheel. The HEDG process necessitates an optimisation of the grinding parameters to achieve desirable results with minimum wheel wear. A poorly designed HEDG process causes abusive wear of the grinding wheel and leads to a damaged workpiece surface. This paper presents a thermal model that has been used to predict temperature in the HEDG process as a function of process parameters. The work explores an enhanced single-pole thermocouple technique that allows measuring contact temperature in deep cutting. A developed software that operates on the thermal model is used to implement a control strategy and to monitor the grinding process in real time. The results of the tests are presented in terms of measured and predicted temperatures and the specific energy. The paper also puts side by side the performance of metal bond CBN wheel and the high aspect ratio wheel.