DRILLING BIT Russian patent published in 2017 - IPC E21B10/56 E21B10/60 

FIELD: mining.

SUBSTANCE: drilling bit comprises a housing with holes in which carbide inserts with a shank and a working head of stepped configuration are fixed in the frontal plane. The insert has an axial channel which is at least of the working head height, while the height of the working head steps decreases from the top to the shank, and the hardness of the material of each step increases from the center towards the periphery.

EFFECT: improvement efficiency of the drilling bit.

3 cl, 1 dwg