A recent concept called the fragmentation-energy fan has been used to analyze drop weight testing (DWT) data and to obtain both the mathematical form of the breakage index equation, i.e., t10 versus impact energy and the parameter values needed for making an actual prediction with it. The fan is visualized by plotting the progeny size corresponding to a set of percent passing values versus scaled drop energy in log–log scale and fitting straight, i.e., linear fan lines with a common focal point to these data. The fan behavior lies inherent in the fact that the DWT sieving data closely follow the Swebrec distribution. A mathematical expression for t10 in closed form follows directly from a functional inversion, and this expression differs from the forms it has been given by the JKMRC. In most cases five fan lines suffice to provide a very accurate t10 equation. When applied to a suite of eight rocks, ores mostly, the coefficient of determination R2
Laboratory drop weight testing (DWT) of lumps of rock is a way to characterize the breakage properties of ore and rock so that design and modeling of comminution circuits can be made with confidence (Napier-Munn et al. 1996). The DWT yields initially sieving curves for the progeny generated and their dependence on the drop energies Ecs
The JKMRC has been leading in the development of the DWT (Shi 2016), and one of the most extensive available data sets on laboratory drop weight testing (DWT) of lumps of rock, mostly ores, is found in the thesis of Banini (2002) from the JKMRC.
