DRILLING BIT Russian patent published in 2019 - IPC E21B10/43 

FIELD: drilling of soil and rocks.

SUBSTANCE: invention relates to cutting-abrasive type tool for drilling of wells for liquid and gaseous minerals, namely to drilling blade chisels reinforced with diamond-hard-alloy plates PDC. Drill bit comprises housing with blades therein, in which there are cutting plates PDC. PDC cutting plates are fixed on blades from centre to periphery in diametral plane along logarithmic spiral with negative front angles varying from minus 30° in the centre to minus 10° at periphery with one-degree interval in the form of double thread.

EFFECT: technical problem of the proposed invention is creation of such drill chisel, which equally well destructs rocks from 4 to 9 category by drillability, that is to increase mechanical speed of drilling of rocks by 20 and more percent.

1 cl, 4 dwg, 1 tbl