Drill bits and methods relating thereto are disclosed. In an embodiment, the drill bit includes a body having a plurality of legs each having a lower section that has a leading surface and a trailing surface. A plurality of cone cutters are each rotatably mounted to the lower section of one of the legs, each having a cone axis, and including a first plurality of cutter elements arranged about the cone axis such that each is shear the formation when the body is rotated about the bit axis.

Cutting elements include a diamond-bonded body attached with a substrate. The substrate has a coercivity of greater than about 200 Oe, and has a magnetic saturation of from about 73 to 90. The diamond-bonded body has a compressive stress at the surface of greater than about 0.9 GPa after heat treatment, and greater than about 1.2 GPa prior to heat treatment.

A polycrystalline element includes a table formed of polycrystalline diamond. The table includes a first surface; a second surface spaced apart from the first surface; and at least one side extending between the first surface and the second surface. The table also includes a plurality of extensions also formed of polycrystalline diamond, wherein at least one extension of the plurality of extensions extends away from at least one of the first surface and the at least one side. The at least one extension of the plurality of extensions includes a first portion that is polyhedral shaped. Optionally, the polycrystalline diamond of at least one extension of the plurality of extensions is contiguous with the polycrystalline diamond of the table. The polycrystalline element may be used in downhole tools for boring and well drilling, machine tools, and bearings.

A polycrystalline element includes a table formed of polycrystalline diamond. The table includes a first surface; a second surface spaced apart from the first surface; and at least one side extending between the first surface and the second surface. The table also includes a plurality of extensions also formed of polycrystalline diamond, wherein at least one extension of the plurality of extensions extends away from at least one of the first surface and the at least one side. The at least one extension of the plurality of extensions includes a first portion that is polyhedral shaped. Optionally, the polycrystalline diamond of at least one extension of the plurality of extensions is contiguous with the polycrystalline diamond of the table. The polycrystalline element may be used in downhole tools for boring and well drilling, machine tools, and bearings.

A hybrid bit with roller cones having inserts is disclosed, includes a bit body, blades and roller cones. All the fixed cutting elements at the inner cone section, nose section and shoulder section of blades herein constitutes two sets of corresponding fixed cutting elements respectively, forming two profile envelopes of fixed cutting elements at least in the interval at the nose section and shoulder section, the two profile envelopes of fixed cutting elements are spaced at high and low intervals at the nose section and shoulder section, forming two stages of cutting by fixed cutting elements; and the cutting position of the cone insert mainly corresponds to the nose section and shoulder section of blades, the outermost cutting profile envelope of cone inserts formed by all or part of cutting elements on cones herein is higher than the outermost cutting profile envelope of fixed cutting elements, forming the third stage of cutting. The invention can effectively develop rate of penetration in hard and plastic formation, maintain and prolong the service life of the hybrid bit, and broaden the formation suitability of the hybrid bit.

A hybrid bit with roller cones having inserts is disclosed, includes a bit body, blades and roller cones. All the fixed cutting elements at the inner cone section, nose section and shoulder section of blades herein constitutes two sets of corresponding fixed cutting elements respectively, forming two profile envelopes of fixed cutting elements at least in the interval at the nose section and shoulder section, the two profile envelopes of fixed cutting elements are spaced at high and low intervals at the nose section and shoulder section, forming two stages of cutting by fixed cutting elements; and the cutting position of the cone insert mainly corresponds to the nose section and shoulder section of blades, the outermost cutting profile envelope of cone inserts formed by all or part of cutting elements on cones herein is higher than the outermost cutting profile envelope of fixed cutting elements, forming the third stage of cutting. The invention can effectively develop rate of penetration in hard and plastic formation, maintain and prolong the service life of the hybrid bit, and broaden the formation suitability of the hybrid bit.

Polycrystalline diamond constructions comprise a diamond body attached with a substrate during high pressure/high temperature processing, and include a modified reaction zone interposed between the body and substrate that is engineered to minimize or eliminate unwanted back diffusion of carbon from the diamond body into the substrate during the high pressure/high temperature processing.

A rotating cutter single cone bit includes a bit body and a cone that is rotatably coupled to the bit body. Cutters are arranged on the cone. At least one cutter on the cone is a rotating cutter. The rotating cutter forms a rotational connection with the cone. The geometric center of the front cutting face of the rotating cutter or the front cutting face of the rotating cutter is offset from the rotating axis of the rotating cutter, and the geometric center of the rear cutting face or the rear cutting face of the rotating cutter is on the same side of the offset of the front cutting face. The front cutting face is closer to the rotating axis of the rotating cutter than the rear cutting face. The rotating cutter is rotatable about the rotating axis of the rotating cutter on the cone.

A rotating cutter single cone bit includes a bit body and a cone that is rotatably coupled to the bit body. Cutters are arranged on the cone. At least one cutter on the cone is a rotating cutter. The rotating cutter forms a rotational connection with the cone. The geometric center of the front cutting face of the rotating cutter or the front cutting face of the rotating cutter is offset from the rotating axis of the rotating cutter, and the geometric center of the rear cutting face or the rear cutting face of the rotating cutter is on the same side of the offset of the front cutting face. The front cutting face is closer to the rotating axis of the rotating cutter than the rear cutting face. The rotating cutter is rotatable about the rotating axis of the rotating cutter on the cone.

A drilling tool includes a pilot bit coupled to an eccentric reamer that has a reaming side and a stabilizing side. A fluid passageway extends between the reamer and the pilot bit, and the tool includes at least one upwardly-directed nozzle in fluid communication with the fluid passageway and positioned on the stabilizing side of the reamer. The reamer may include a plurality of angularly spaced blades on the reaming side that radially extend a first distance, the reamer blades being disposed within a first arcuate segment defined by the two most distant reamer blades. One or more stabilizing blades extend a second distance that is less than the first distance, the stabilization blades being disposed within a second arcuate segment defined by the two most distant reamer blades and that has the angular measure equal to 360 degrees minus the first arcuate segment.