In the rock-drilling industry, double layer polycrystalline diamond-hardmetal (Dia-HM) inserts for cutting tools are subjected to elevated levels of wear due to the high power involved in the process. A research performed by focusing on the wear mechanism has shown that the complexity of the actual industrial operation can be reproduced in laboratories. The present work developed a methodology to calculate the theoretical values of wear of drilling tools. The main parameter selected for this methodology was the amount of disaggregated rock. The information acquired through this methodology gives one a complete perspective about the application of Dia-HM inserts to be used in drilling tools.