DRILLING BIT Russian patent published in 2012 - IPC E21B10/02 

FIELD: oil and gas industry.

SUBSTANCE: bit includes bit blank with slots on the edge, in which rock-destructing inserts are fixed. The latter contain hard-alloy cutters fixed on the front edge of support plate by means of overwrapping plate and mounting elements. The peculiar feature of the bit is that overwrapping plate of the insert is provided with projections located on the side of working edge of the bit with possibility of interaction with working edges of hard-alloy cutters. At that, the number of projections on the edge of each overwrapping plate corresponds to the number of cutters on the insert; at that, projections of overwrapping plate are offset relative to working edge of hard-alloy cutters to the side opposite to the working face. Tail end of hard-alloy cutters has equal cross section throughout the length. Version of design of mounting plates as an integral part of overwrapping plate in the form of corrugated belt with slots and platform for hard-alloy cutters is provided; at that, platform is located between overwrapping plate and corrugated belt.

EFFECT: use of the proposed bit allows considerably reducing the hard alloy consumption, simplifying the manufacturing technique of cutters at simultaneous improvement of their quality and thus increasing its operation efficiency and reducing the cost of drilling operations.

4 cl, 4 dwg