TAPGATBOOR VOOR EEN HOOGOVEN.

摘要

A blast furnace taphole drill has a flaring head (3) with cutting edges (5) at its cutting end formed by intersecting angled faces. A central bore (4) carries cleaning air to the cutting end. To prevent blockage of the cleaning air bore (4) by debris and possible jamming of the drill, the head has deep radial grooves (6) formed at the bottoms of the valley shapes between the cutting edges (5). The grooves (6) extend radially from the air bore (4) and conduct the air so that it can get behind or under jammed debris. Reduced taphole drilling times can be achieved.