Deep grinding production times
High Efficiency Deep Grinding (HEDG) is a relatively new machining technique that promises significantly higher stock removal rates than leading conventional methods like shallow or creep-feed grinding. As such, HEDG has the potential to simplify the supply chain process and drastically reduce production times. Materials experts from Cranfield University put HEDG to the test during a GROWTH Programme project aimed at increasing the competitiveness of the European automotive industry. A wheel made from Cubic Boron Nitride (CBN), second only to diamonds in hardness, was used to machine Continuously Variable Transmission (CVT) parts (e.g. gear shafts). Analysis of thermal modelled data collected while modifying various grinding parameters, allowed the scientists to determine the ideal conditions for maximum stock removal without exceeding the burn threshold. In addition, the challenges associated with applying HEDG to cylindrical grinding, which is critical for automotive parts, were overcome. Stock removal rates in excess of two cubic centimetres per second were achieved during the trials. Mineral oil was identified as a preferable alternative to water-based fluids for lubricating the work area, though some safety concerns must be resolved prior to use on an industrial scale. The adoption of HEDG by European auto manufacturers could prove to be an important advantage in the increasingly competitive global marketplace.
