DRILL BIT AND METHOD OF SECURING OF ITS INSERTS Russian patent published in 2015 - IPC E21B10/16 E21B10/43 

FIELD: mining.

SUBSTANCE: invention relates to rock destructing tools provided with hard-alloy inserts. Drill bit comprises the body with bores to receive the hard-alloy inserts with cylindrical stems. Sleeves of resilient material shaped to barrel with bottom hole are arranged between the bore walls and insert outer surface. Note here that inserts have the stepped stem. Smaller diameter stage height is not smaller than the depth of the barrel bottom depth. Diameter of this stage complies with the barrel bottom opening diameter. The end of lower step of every stem can have the spherical ledge. Bottom hole can have the mating recess. Claimed method consists in fitting the drill bit cylindrical stems in the drill bit body holes. Note here that resilient sleeves are fitted between hole walls and outer surface of insert stems and stretched in lengthwise direction before fitting them in place.

EFFECT: simplified fabrication and attachment.

3 cl, 1 dwg