Patent ID: 8191657
Filing Date: 2012-06-05
Classification: E21B

Abstract:
1. A rotary drag bit for cutting casing and drilling subterranean formations, comprising: a bit body having a face extending from a centerline to a gage; an inverted cone formed in the face of the bit body; a plurality of blades comprising a particulate abrasive material on the face and extending generally radially outwardly toward the gage; and a plurality of discrete, mutually separated cutting structures protruding from at least one blade of the plurality of blades, at least one cutting structure of the plurality of discrete, mutually separated cutting structures comprising a particulate abrasive material and at least two cutting elements formed at least partially within the at least one cutting structure of the plurality of discrete, mutually separated cutting structures, wherein one cutting element of the at least two cutting elements rotationally leads at least another cutting element of the at least two cutting elements in a direction of intended rotary drag bit rotation.