### Application of Operating Work Indices in Autogenous ...

= SAG mill feed sample mass, grams The ball mill pinion energy is determined from the Bond the Third Theory of Comminution : S d-BWI = 1.102 * 44.5 / (P cs 0.23 G pb 0.82) / (10 / P 80 1/2 – 10 / F 80 1/2) where : S d-BWI = Bond ball mill work index on SAG ground ore, kWh/ton ground F 80 = 80% passing of SAG ground of the test feed size ...