Drill crown for drilling rock, has trailing and leading rock machining portions separated by axial distance in direction of trailing end of crown

摘要

At least one of the trailing rock machining portions is separated by an axial distance from the leading rock machining portion in the direction of the trailing end of the drill crown. The crown has a single-piece construction, comprising a connecting part for fixing to a drill rod, a guide part, and an excavating part with a leading and at least one trailing rock machining portion located on one side of the guide part within a segment defined by a sector angle.