METHOD OF STRENGTHENING OF DRILL BITS REINFORCED BY DIAMOND-CARBIDE PLATES Russian patent published in 2015 - IPC E21B10/46 C21D6/04 

FIELD: mining.

SUBSTANCE: method of strengthening of drill bits reinforced by diamond-carbide plates includes cold treatment, at that cold treatment is performed by bits with temperature 20°C immersion in liquid nitrogen with temperature minus 196°C for 15 minutes followed by assurance of bit temperature 20°C, then bits are additionally subjected for 15 minutes to permanent magnetic field with intensity 4000 oersted.

EFFECT: reduced wear-out of diamond-carbide plates, and increased passage of drill bits through rocks of average category of drillability.

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