Masonry bit for impact drill - has cruciform tungsten carbide insert with shorter cutting edges along one axis

摘要

The masonry drill bit is for use with rotary, rotary-impact and hammer-type drills. A protruding tungsten carbide insert is embedded in the head of the stem and is in one piece, with three or more cutting arms joined together at the bit axis. Where the cutting edges of the insert are in a cruciform pattern (9, 11) those (5') along one axis are of full length. The edges (5") on the axis at right angles to it are shortened.