Determining the Bond Efficiency of industrial grinding circuitsBond Ball Mill Test Work Index (kWh/t). Wic. Bond Impact . and mill feed rate). 7. DETERMINING THE BOND EFFICIENCY OF A. GRINDING CIRCUIT. 7.1 Method. In the plant: 1. Define the circuit for which the Bond Efficiency is to be determined. 2. ... tation “Bond Efficiency SLC (rev3)-print.pdf” available for download at.ball mill efficiency equation pdf,The determination of the efficiency of the milling process - SAIMMTraditionally, the absolute efficiency of a comminution process is defined as the ratio of the free boundary surface energy, summed over the new surface produced, to the work supplied. According to this definition of efficiency, ball milling is only about I per cent efficient and one is tempted to believe that there is considerable.