DRILLING BIT Russian patent published in 1997 - IPC

FIELD: drilling equipment. SUBSTANCE: this bit is intended for drilling blast-holes by drilling machines of percussive-turning and percussive-rotary action. Drilling bit has body with inner seating socket for connection with rod and with holes for air purging and flushing of blast-holes, and hard-alloy inserts fixed in bit body. Made in body are partly open taper seats with geometric axes which are crossing with bit axis. Hard-alloy inserts are made in the form of truncated cones with cone angle being less than angle of friction of insert material and bit body and they are installed in taper seats with interference. EFFECT: high efficiency. 4 dwg