A NEW HELICAL DRILL CONSTRUCTION WITH INCREASED DURABILITY.

Decrease of the unitary energetic load along the cutting edge with variable working angle, by increasing of the number of cutting edges in the construction of the helical drill, and, in the same time, the accomplishment of an evenness unitary energetic load may be assumptions for decreasing of the temperature of the tool cutting edge at its periphery. This will leads to the decreasing of the tool wear rate, hence the increasing of the tool's durability. In this paper, we present experimental research on curved cutting edge drills, regarding the speed-durability dependence in processing carbon steel. We observed that durability of curved cutting edge drills is superior to durability of standard drills for the same working conditions. [ABSTRACT FROM AUTHOR]