CROWN BIT Russian patent published in 2012 - IPC E21B10/02 E21B10/58 

FIELD: oil and gas industry.

SUBSTANCE: crown comprises a crown ring with slots at the end, where hard-alloy plates of rectangular shape are fixed with through channels. Each plate is made with one diagonal link that connects a lower well-calibrating section of the plate with its upper core-calibrating section, at the same time in plan it has a shape of a trapezoid, the larger base of which is arranged at the side of well wells, at the same time hard-alloy plates in plan have a shape of a trapezoid, the larger base of which is located at the side of the well walls.

EFFECT: application of the proposed crown makes it possible to considerably simplify the technology of cutters manufacturing with simultaneous improvement of their quality and therefore to increase efficiency of its operation and to reduce cost of drilling works.

2 cl, 3 dwg