Patent ID: 8439136
Filing Date: 2013-05-14
Classification: E21B

Abstract:
1. A drill bit for earth boring comprising: a bit body having a first end and a second end spaced apart from said first end; connection means connected to said bit body for coupling said bit body to a rotating means for providing rotational torque to said bit body; a cone section proximate said second end that extends a first radial distance from a centerline of said drill bit; a flank section that extends from proximate said first radial distance to a second radial distance from said centerline that is greater than said first radial distance; a shoulder section that extends from proximate said second radial distance to a third radial distance greater than said second radial distance, said third radial distance proximate a gauge radial distance that defines a maximum radius of said drill bit; and, a first plurality of blades connected to said bit body and extending away from said bit body from said shoulder section to said cone section, said first plurality of blades having a first plurality of cutters positioned in said cone section and no cutters positioned outside of said cone section; and, a second plurality of blades connected to said bit body and extending away from said bit body, said second plurality of blades having a second plurality of cutters positioned in at least one of said flank section and said shoulder section and said second plurality of said blades having no cutters positioned within said cone section.