Abstract: A drag-type drill bit comprises a bit body having an operating end face and a multiplicity of superhard cutting elements interlocked to the bit body. The cutting elements define a multiplicity of cutting areas dispersed over the operating end face of the bit body in a pattern adapted to cause the cutting areas to cut an earth formation to a desired three-dimensional profile as the bit body is rotated. The cutting areas have back rake angles which become more negative with distance from said profile.

Abstract: The invention comprises a drag-type drill bit and a cutting member therefor. Each of the cutting members comprises a stud having a shank adjacent one end mounted in a respective bore in the bit body and a head adjacent the opposite end projecting outwardly from the bit body. The head has a lip formation adjacent the juncture of the head and shank. The lip extends laterally outwardly with respect to the shank to overly the outer surface of the bit body adjacent the respective bore. The cutting face is concave, presenting a plurality of different back rake angles, which angles increase with distance from the lip formation.

Abstract: Disclosed is a method and apparatus for mechanically and metallurgically holding a cutter in a drill bit pocket. The method includes using powder metallurgy techniques in the formation of a drill bit member having a plurality of pockets configured to inhibit displacement of cutters out of the pockets in a direction transverse to the drill bit working surface. The method further includes the steps of metallurgically bonding and mechanically engaging the cutter with the cutter pocket. The drill bit manufactured in accordance with the methods of the present invention include a carbide menstrum drill bit head having a working surface with a plurality of fluid courses and nozzles thereon in adjacent relationship with a plurality of cutter blade bands comprising a series of cutter pockets having cutters disposed therein in a fashion parallel with the working surface.