Ultra hard insert cutters for heel row rotary cone rock bit applications

A rotary cone rock bit for drilling boreholes in an earthen formation, one or more rotary cones rotatively retained on a bearing connected to said rock bit forms a circumferential heel row with extended shaped cutters spaced within said heel rows, said shaped cutters being tungsten carbide bodied inserts having a first base end and a cutter end, said second cutter end consisting of a polycrystalline diamond bonded to a tungsten carbide substrate that is subsequently metalurgically attached to said second cutter end of said body, said second cutting end of said body serves as a backup support for said substrate, said diamond forming said cutting edge, said cutting edge forming a substantially straight line across said cutter end, said cutting edge being oriented with a side rake angle with respect to a radial orientation from an axis of said cone, the cutting edge alignment serves to direct debris away from the bearing surfaces, each of said shaped cutters shear a borehole wall formed by said formation as said rotary cone rotates against a bottom of said borehole, said shaped cutters serve to maintain the borehole diameter.