CONE BIT Russian patent published in 2009 - IPC E21B10/16 

FIELD: oil and gas production.

SUBSTANCE: invention is related to drilling rock-breaking tool, namely to cone bits for drilling of inclined and horizontal wells. Bit includes three cutters equipped with hard-alloy teeth in the form of central crowns at all cutters, double-row peripheral crowns at two cutters and single-row peripheral crown on one cutter. Reverse cones of cutters are equipped with external and internal rows of calibrating teeth. On contours of small bases of reverse cutter cones there are platforms milled as parallel to cone base, and wedge teeth of internal calibrating row are installed on them with working heads aflush with side surface of reverse cone. Working surfaces of teeth on cutters with double-row peripheral crowns are arranged along tangents to circumference of reverse cone base, and working surfaces of teeth on cutter with single-row peripheral crown are installed radially to circumference of reverse cone base. Calibrating teeth of internal row on cutters with double-row peripheral crowns are arranged in gaps of peripheral row teeth with the following alternation - one tooth in one gap, two teeth in the neighboring gap, then one tooth in the next gap, etc.

EFFECT: reduced bit seizure risk in inclined and horizontal drilling, improved passability of tools and pipe casings in well and extended duration of cutter bases.

2 cl, 3 dwg