Abstract: A cutting element includes a body, a non-planar cutting face formed on a first end of the body, and an edge formed around a perimeter of the cutting face. The cutting face includes a central raised portion, and the edge has an edge angle defined between the cutting face and a side surface of the body. The edge angle varies around the perimeter of the cutting face and includes an acute edge angle defined by a portion of the cutting face extending downwardly from the edge to a depth from the cutting angle. The portion of the edge defining the acute edge angle may be directly adjacent: a side surface of the cutting element; a bevel of the cutting element; or a flat region at the perimeter of the cutting element or bevel.

Abstract: A drill bit for drilling a borehole in earth formations may include a bit body having a bit axis and a bit face; a plurality of blades extending radially along the bit face; and a plurality of cutting elements disposed on the plurality of blades, the plurality of cutting elements comprising: at least one cutter comprising a substrate and a diamond table having a substantially planar cutting face; and at least two non-planar cutting elements comprising a substrate and a diamond layer having a non-planar cutting end, wherein in a rotated view of the plurality of cutting elements into a single plane, the at least one cutter is located a radial position from the bit axis that is intermediate the radial positions of the at least two non-planar cutting elements.

Abstract: A drill bit may include a bit body and at least two cones assemblies including at least two drive cylinders having at least two cones. The at least two cone assemblies are mounted on the bit body. The drill bit may also include an indexing mechanism coupled to the bit body and configured to rotate and lock at least one drive cylinder. A method of operating the drill bit may include providing fluid to the drill bit, rotating the drill string to drill formation, moving the indexing mechanism an axial distance within a central chamber of the drill bit, rotating the at least two indexable structures as the indexing mechanism moves, and locking the at least two indexable structures.

Abstract: A secondary cutting structure for use in a drilling assembly includes a tubular body, and a block, extendable from the tubular body, the block including a first arrangement of cutting elements disposed on a first blade, a first stabilization section disposed proximate the first arrangement of cutting elements, a second arrangement of cutting elements disposed on the first blade, and a second stabilization section disposed proximate the second arrangement of cutting elements. A method of drilling includes disposing a drilling assembly in a wellbore, the drilling assembly including a secondary cutting structure having a tubular body and a block, extendable from the body, the block including at least three blades, actuating the secondary cutting structure, wherein the actuating includes extending the block from the tubular body, and drilling formation with the extended block.

Abstract: A secondary cutting structure for use in a drilling assembly includes a tubular body, and a block, extendable from the tubular body, the block including a first arrangement of cutting elements disposed on a first blade, a first stabilization section disposed proximate the first arrangement of cutting elements, a second arrangement of cutting elements disposed on the first blade, and a second stabilization section disposed proximate the second arrangement of cutting elements. A method of drilling includes disposing a drilling assembly in a wellbore, the drilling assembly including a secondary cutting structure having a tubular body and a block, extendable from the body, the block including at least three blades, actuating the secondary cutting structure, wherein the actuating includes extending the block from the tubular body, and drilling formation with the extended block.

Abstract: A cutter assembly may include a multi-piece split sleeve, an inner cutting element having a groove or protrusion formed in a side surface thereof and disposed in the multi-piece split sleeve, and at least one component interfacing at least a portion of the groove or the protrusion to limit axial movement of the inner cutting element with respect to the multi-piece split sleeve, in which the multiple pieces of the split sleeve are joined together at an overlapping joint.

Abstract: A cutting element for a downhole cutting tool including a support element, a shearing element disposed on said support, wherein the shearing element is disposed proximal to a leading edge of the downhole cutting tool, and a retaining element overlaying at least a portion of said shearing element is disclosed.

Abstract: A drill bit for drilling a borehole in a formation, the drill bit including a bit body having a bit face including a cone region, a nose region, a shoulder region, and a gage region, at least one disjointed blade disposed on the bit face, the disjointed blade including a first section beginning proximate a central axis of the bit and extending less than full gage, and a second section beginning a selected distance from the central axis and extending to full gage, and a plurality of cutting elements mounted on the at least one disjointed blade is disclosed.

Abstract: This invention provides an improved cutting element for downhole cutting tools comprising a support element and a shearing element disposed on said support; a drill bit insert comprising a body and said cutting element disposed on said body; and a cutting tool, such as a hole opener or a reamer, comprising said cutting element and/or said drill bit insert. Also provided are methods for forming the said cutting element, drill bit insert and downhole cutting tools and a method for drilling mixed earth formation using the improved downhole cutting tools of the present invention.

Abstract: A cutting element for a downhole cutting tool including a support element, a shearing element disposed on said support, wherein the shearing element is disposed proximal to a leading edge of the downhole cutting tool, and a retaining element overlaying at least a portion of said shearing element is disclosed.

Abstract: An insert for a drill bit which includes a diamond impregnated body, and a shearing portion disposed on said body is shown. In addition, a method for forming a drill bit that includes (a) forming a shearing portion on a diamond-impregnated insert body to form a cutting insert, (b) forming a bit body having a plurality of sockets sized to receive a plurality of the cutting inserts, and (c) mounting the plurality of cutting inserts in the bit body and affixing the plurality of cutting inserts to the bit body; wherein steps (a)–(c) are carried out such that a total exposure of the diamond-impregnated insert to temperatures above 1000° F. is greater than a total exposure of the shearing portion to temperatures above 1000° F.

Abstract: An insert for a drill bit which includes a diamond impregnated body, and a shearing portion disposed on said body is shown. In addition, a method for forming a drill bit that includes (a) forming a shearing portion on a diamond-impregnated insert body to form a cutting insert, (b) forming a bit body having a plurality of sockets sized to receive a plurality of the cutting inserts, and (c) mounting the plurality of cutting inserts in the bit body and affixing the plurality of cutting inserts to the bit body; wherein steps (a)-(c) are carried out such that a total exposure of the diamond-impregnated insert to temperatures above 1000° F. is greater than a total exposure of the shearing portion to temperatures above 1000° F.