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AssigneeSmith International, Inc.
InventorsDavid M. Nguyen, Michael A. Siracki, Stephen G. Southland
Estimating the term…
An improved polycrystalline diamond composite ("PDC") cutter comprises a single or a plurality of secondary PDC cutting surfaces in addition to a primary PDC cutting surface. The two cutting surfaces are spaced apart, resulting in enhanced cutter efficiency and useful life. The primary PDC cutting surface is a polycrystalline diamond layer on an exposed end face of the cutter. A secondary cutting surface is formed by a polycrystalline diamond layer embedded within the body of the cutter. The secondary cutting surface can have a larger diameter than the primary cutting surface so that the forward end of the cutter parallels rock formation during drilling and both cutting surfaces engage the rock formation.
A drag bit comprising a plurality of cylindrical cemented tungsten carbide polycrystalline diamond cutters having two end faces, a body therebetween and a longitudinal axis, wherein the cutters are inserted in an outer body of the bit so that the longitudinal axis of each cutter is approximately perpendicular to a radius of the bit and wherein a portion of each cutter including an end face is exposed, and comprises:
A PDC cutter for insertion into a drag bit at a predetermined angle, the cutter comprising:
A PDC cutter for insertion in a drag bit at a predetermined angle, the cutter comprising:
Dependencies are inferred from the claim text.