PDC DRILL BIT FOR FLUID ABSORPTION ZONE DRILLING Russian patent published in 2020 - IPC E21B10/43 E21B10/55 E21B10/567 E21B10/60 

FIELD: soil or rock drilling.

SUBSTANCE: invention relates to rock-destructing tool used for drilling oil and gas wells, namely to production of drill bits with weapons represented by PDC cutters. Drill bit PDC for drilling a fluid absorption zone comprises a cylindrical body with a thread for connection to a drill string, blades with PDC cutters for breaking rocks, inner cavities and channels for supply of flushing fluid to the bottomhole. PDC cutters are used with pressing at pressure higher than 7 GPa with complete absence of metal inclusions in surface polycrystalline diamond layer, which are installed on blades with negative front angles in range of 21–24° in shoulder part and within 10–14° in central and calibrating parts of drill bit. Channels for supply of flushing fluid have cylindrical infinitely variable shape, inner diameter of which is coated with hard-wearing wear-resistant coating.

EFFECT: technical result consists in improvement of resistance of PDC bits, expansion of functional capabilities of PDC bits when drilling zones of drilling fluid absorption, simplification of design of PDC drill bit.

1 cl, 2 dwg