Abstract: A drill bit including a body having a face and a plurality of blades disposed on the face of the body. Each of the plurality of blades may have a row of cutters disposed thereon, and the rows of cutters may collectively define a cutting profile of the drill bit. At least some of the cutters along the cutting profile may have alternating positive back rake angles. The difference between a majority of back rake angles on adjacent cutters along the cutting profile may be less than 20°.

Abstract: A drill bit including a body having a face and a plurality of blades disposed on the face of the body. Each of the plurality of blades may have a row of cutters disposed thereon, and the rows of cutters may collectively define a cutting profile of the drill bit. At least some of the cutters along the cutting profile may have alternating positive back rake angles. The difference between a majority of back rake angles on adjacent cutters along the cutting profile may be less than 20°.

Abstract: A drill bit including a body having a face and a plurality of blades disposed on the face of the body. Each of the plurality of blades may have a row of cutters disposed thereon, and the rows of cutters may collectively define a cutting profile of the drill bit. At least some of the cutters along the cutting profile may have alternating positive back rake angles. The difference between a majority of back rake angles on adjacent cutters along the cutting profile may be less than 20°.

Abstract: A drill bit including a body having a face, a blade disposed on the face, and a row of cutters disposed on the blade. At least some of the cutters may have alternating positive back rake angles. The difference between a majority of back rake angles on adjacent cutters may be less than 20°.

Abstract: A drill bit including a body having a face, a blade disposed on the face, and a row of cutters disposed on the blade. At least some of the cutters may have alternating positive back rake angles. The difference between a majority of back rake angles on adjacent cutters may be less than 20°.

Abstract: A drill bit including a body having a face and a plurality of blades disposed on the face of the body. Each of the plurality of blades may have a row of cutters disposed thereon, and the rows of cutters may collectively define a cutting profile of the drill bit. At least some of the cutters along the cutting profile may have alternating positive back rake angles. The difference between a majority of back rake angles on adjacent cutters along the cutting profile may be less than 20°.

Abstract: A rotating bit with cutters used in drilling operations to advance a borehole in the earth. The bit includes column cutters in the bit body in a recessed central area. The column cutters contact a column of borehole material that is formed during operation. The column cutters are oriented to fracture the column, producing larger cuttings or chips, and to exert a force on the column to limit lateral movement of the bit during operation.

Abstract: A rotating bit with cutters used in drilling operations to advance a borehole in the earth. The bit includes column cutters in the bit body in a recessed central area. The column cutters contact a column of borehole material that is formed during operation. The column cutters are oriented to fracture the column, producing larger cuttings or chips, and to exert a force on the column to limit lateral movement of the bit during operation.

Abstract: A drill bit that provides enhanced stability and a method for manufacturing such bit. In a preferred embodiment, the hybrid drill bit includes a single short driven blade in the shoulder region of the bit having each of its primary cutters plural set, sharing a common radial/elevational position with a primary cutter in an adjacent blade. All other primary cutters of the drill bit are single set at unique radial/elevational positions. The trailing plural-set cutters do less work than the other cutters and disrupt resonance and the feedback mechanism that leads to vibration, instability and whirling. In alternate embodiments, multiple blade pairs or groups may have primary cutters in the shoulder region that are plural set, sharing common radial/elevational positions with other primary cutters.

Abstract: Methods of forming bit bodies for earth-boring bits include assembling green components, brown components, or fully sintered components, and sintering the assembled components. Other methods include isostatically pressing a powder to form a green body substantially composed of a particle-matrix composite material, and sintering the green body to provide a bit body having a desired final density. Methods of forming earth-boring bits include providing a bit body substantially formed of a particle-matrix composite material and attaching a shank to the body. The body is provided by pressing a powder to form a green body and sintering the green body. Earth boring Earth-boring bits include a unitary structure substantially formed of a particle-matrix composite material. The unitary structure includes a first region configured to carry cutters and a second region that includes a threaded pin. Earth-boring bits include a shank attached directly to a body substantially formed of a particle-matrix composite material.