Abstract: A drill bit includes a bit body providing one or more blades and defining a cone section extending from a centerline of the bit body a first distance, a nose section extending from the cone section a second distance, a shoulder section extending from the nose section a third distance, and a gauge section extending from the shoulder section a fourth distance. The drill but further includes one or more cutting elements mounted to the one or more blades outside of the cone section such that the cone section is void of cutting elements, and a plurality of milling elements secured to the bit body within the cone section.

Abstract: A method of manufacturing a roller cone includes machining a cone blank and thereby defining one or more land surfaces and one or more insert grooves on the cone blank, surface hardening the cone blank, and milling a plurality of recesses into at least one of the one or more land surfaces. The method further includes subjecting the cone blank to a quenching process, forming an insert hole at each recess, and inserting an insert into each insert hole.

Abstract: A drill bit includes a bit body providing one or more blades and defining a cone section extending from a centerline of the bit body a first distance, a nose section extending from the cone section a second distance, a shoulder section extending from the nose section a third distance, and a gauge section extending from the shoulder section a fourth distance. The drill but further includes one or more cutting elements mounted to the one or more blades outside of the cone section such that the cone section is void of cutting elements, and a plurality of milling elements secured to the bit body within the cone section.