The wear of single flute gun drill and tool life tests

Abstract

In the machining industry, the demand for higher productivity can be gained with higher cutting parameters and also by developing new tools and work materials. Drill condition monitoring assists in choosing suitable cutting parameters for specific applications, e.g. for new work material. In addition, tool wear can be measured quite eas-ily in laboratory conditions.The object of this study was to ascertain the wear-ing of the gun drill and the measured wear types that the best indicate the tool condition. In the present study, dif-ferent tool wear types were found in the gun drill. To test these wear types, gundrilling tests were carried out by us-ing two different kinds of drill geometries. The best wear types for predicting the condition of a gun drill seem to be flank wear in the drill tip (CT), the average flank wear (VB) and the mean and maximum flank wear (VB, V´B) on the outside edge.