Drill tool, has connected straight and helical drilling debris grooves in adjoining cutting head and guide parts

摘要

The cutting head (120) has at least one guide section and at least one straight drilling debris groove (124). The cutting head is connected to a helical guide part (140) with at least one helical guide section (146) and at least one helical drilling debris groove (140) in communication with the straight groove. An independent claim is also included for a drill tool comprising a cutting head with at least one guide section and at least one straight drilling debris groove, an intermediate part with at least one helical drilling debris groove in communication with the straight groove and a helical guide part with at least one helical guide section diametrically opposed to the guide section on the cutting head in the radial direction and at least one straight drilling debris groove in communication with the helical groove.