Abstract: An earth-boring bit comprising a bit body configured at its upper extent for connection into a drillstring. A selected number of fixed blades extend downward from the bit body and a selected number of rolling cutters are mounted for rotation on the bit body. A plurality of rolling-cutter cutting elements are arranged on each rolling cutter and a plurality of fixed-blade cutting elements are arranged on each fixed blade. The selected number of fixed blades exceeds the selected number of rolling cutters by at least one.

Abstract: A drill bit having a bit body includes a blade face surface on at least one blade extending longitudinally and radially outward over a face of the bit body. The blade face surface of the at least one blade includes a contact zone and a sweep zone. The sweep zone rotationally trails the contact zone with respect to a direction of intended bit rotation about a longitudinal axis of the bit body provides reduce rubbing contact when engaging with a subterranean formation.

Abstract: A drill bit that includes a boss extending rotationally forward of at least one blade thereof in a gage region of a bit body for increasing stability and reducing impact shock caused by a lateral imbalance force acting on the bit while drilling a subterranean formation is disclosed. The boss includes a circumferential bearing surface that rotationally precedes a circumferential bearing surface of the at least one blade. A drill bit that includes a boss having a nozzle port extending therein is also disclosed.

Abstract: A drill bit includes a bit body having a face on which two different types of cutters are disposed, the first type being cutting elements suitable for drilling at least one subterranean formation and the second type being at least one of an abrasive cutting structure and an abrasive cutting element suitable for drilling through a casing shoe, reamer shoe, casing bit, casing or liner string and cementing equipment or other components as well as cement Methods of forming earth-boring tools are also disclosed.

Abstract: A fixed cutter rotary drill bit having gauge cutting elements at large back rake angles are disclosed. The gauge is located at the outer diameter side wall portion of the bit that extends from the cutting end. The gauge and its cutting components contact the side wall of the bore hole during drilling operations. The gauge cutting elements may be configured at a back rake angle in a range of about 40° to 70°.

Abstract: A rotary drag bit includes a bit body having a face and an axis, a plurality of blades extending radially and longitudinally outward from the face, and at least one split cutter set. The split cutter set includes a plurality of cutters, where at least two of the cutters are primary and/or kerfing cutters located on different blades of the plurality of blades. The pair of primary and/or kerfing cutters of the split cutter set may be located substantially the same radial distance from a center line, or axis of rotation, of the bit and located at substantially the same longitude, or elevation, on the bit as one another, or follow substantially the same rotational or helical cutting path as each other.

Abstract: A rotary drag bit includes a primary cutter row comprising at least one primary cutter, and at least two additional cutters configured relative to one another. In one embodiment, the cutters are backup cutters of a cutter group located in respective first and second trailing cutter rows, oriented relative to one another, and positioned to substantially follow the at least one primary cutter. The rotary drag bit life is extended by the backup cutter group, making the bit more durable and extending the life of the cutters. In other of the embodiments, the cutters are configured to selectively engage a subterranean formation material being drilled, providing improved bit life and reduced stress upon the cutters. Still other embodiments of rotary drag bits include backup cutter configurations having different backrake angles and siderake angles, including methods therefor.

Abstract: A rotary drag bit includes a primary cutter row comprising at least one primary cutter and a multiple backup cutter group. The multiple backup cutter group comprises a first and second trailing cutter row, each comprising at least one cutter positioned to follow the at least one primary cutter. The rotary drag bit life is extended by the multiple backup cutter groups making the bit more durable and extending the life of the cutters. Further, the cutters of the multiple backup cutter group are configured to selectively engage a subterranean formation material being drilled, providing improved bit life and reduced stress upon the cutters. Other embodiments of rotary drag bits are provided.

Abstract: A rotary drag bit and method for drilling subterranean formations, including a bit body being provided with at least one cutter thereon exhibiting reduced, or limited, exposure to the formation, so as to control the depth-of-cut of the at least one cutter, so as to control the volume of formation material cut per bit rotation, as well as to control the amount of torque experienced by the bit and an optionally associated bottomhole assembly regardless of the effective weight-on-bit are all disclosed. The exterior of the bit preferably includes a plurality of blade structures carrying at least one such cutter thereon and including a sufficient amount of bearing surface area to contact the formation so as to generally distribute an additional weight applied to the bit against the bottom of the borehole without exceeding the compressive strength of the formation rock.

Abstract: A rotary drag bit and method for drilling subterranean formations, including a bit body being provided with at least one cutter thereon exhibiting reduced, or limited, exposure to the formation, so as to control the depth-of-cut of the at least one cutter, so as to control the volume of formation material cut per bit rotation, as well as to control the amount of torque experienced by the bit and an optionally associated bottomhole assembly regardless of the effective weight-on-bit are all disclosed. The exterior of the bit preferably includes a plurality of blade structures carrying at least one such cutter thereon and including a sufficient amount of bearing surface area to contact the formation so as to generally distribute an additional weight applied to the bit against the bottom of the borehole without exceeding the compressive strength of the formation rock.

Abstract: A rotary drill bit for drilling subterranean formations configured with at least one protective structure proximate to the rotationally leading and trailing edges of a gage trimmer, wherein the at least one protective structure is positioned at substantially the same exposure as its associated gage trimmer. Particularly, the apparatus of the present invention may provide protection for gage trimmers during drilling, tripping, and/or rotation within a casing; i.e., when changing a drilling fluid. Protective structures may be configured and located according to anticipated drilling conditions including helix angles. In addition, a protective structure may be proximate to more than one gage trimmer while having a substantially equal exposure to each associated gage trimmer. Methods of use and a method of rotary bit design are also disclosed.

Abstract: A rotary drag bit and method for drilling subterranean formations including a bit body being provided with at least one cutter thereon exhibiting reduced, or limited, exposure to the formation so as to control the depth-of-cut of the at least one cutter, so as to control the volume of formation material cut per bit rotation, as well as to control the amount of torque experienced by the bit and an optionally associated bottomhole assembly regardless of the effective weight-on-bit. The exterior of the bit preferably includes a plurality of blade structures carrying at least one such cutter thereon and including a sufficient amount of bearing surface area to contact the formation so as to generally distribute an additional weight applied to the bit against the bottom of the borehole without exceeding the compressive strength of the formation rock.

Abstract: A rotary drag bit and method for drilling subterranean formations including a bit body being provided with at least one cutter thereon exhibiting reduced, or limited, exposure to the formation so as to control the depth-of-cut of the at least one cutter, so as to control the volume of formation material cut per bit rotation, as well as to control the amount of torque experienced by the bit and an optionally associated bottomhole assembly regardless of the effective weight-on-bit. The exterior of the bit preferably includes a plurality of blade structures carrying at least one such cutter thereon and including a sufficient amount of bearing surface area to contact the formation so as to generally distribute an additional weight applied to the bit against the bottom of the borehole without exceeding the compressive strength of the formation rock.

Abstract: A rotary drill bit for drilling subterranean formations configured with at least one protective structure proximate to the rotationally leading and trailing edges of a gage trimmer, wherein the at least one protective structure is positioned at substantially the same exposure as its associated gage trimmer. Particularly, the apparatus of the present invention may provide protection for gage trimmers during drilling, tripping, and/or rotation within a casing; i.e., when changing a drilling fluid. Protective structures may be configured and located according to anticipated drilling conditions including helix angles. In addition, a protective structure may be proximate to more than one gage trimmer while having a substantially equal exposure to each associated gage trimmer. Methods of use and a method of rotary bit design are also disclosed.

Abstract: A fixed cutter, or rotary drag, bit exhibiting enhanced lateral stability for drilling subterranean formations and a method of drilling. The bit includes one or more gage pads longitudinally extended in the direction of the leading end of the bit and preferably forwardly of the bit face, the gage pads and preferably the adjacent shoulder regions each bearing at least one cutting element thereon exhibiting a reduced exposure in comparison to cutting elements carried on the face of the bit. The increased gage pad area may be employed as a bearing area to accommodate a large resultant lateral force vector and the extended, reduced-exposure cutting element-carrying gage pads and adjacent shoulder regions may be deployed about the entire circumference of the bit so the direction of any resultant force vector is substantially immaterial to the bit design.

Abstract: A cutter and a drill bit having such cutters for drilling subterranean formations including a superabrasive table formed on an end face of a supporting substrate, there being an interface between the table and the end face including a topographic configuration including at least one, and preferably a plurality of, annular arcuate surfaces centered about the centerline of the cutter and at least one recessed region or groove extending across a substantial portion of the end face. The topographic configuration of the end face is of an orientation and radial width sufficient to accommodate resultant loading of the cutting edge of the cutter throughout a variety of angles with vectors normal to the surface at a variety of angles such that at least one normal vector is aligned substantially parallel to the resultant loading on the cutting edge.

Abstract: A rotary drag bit and method for drilling subterranean formations including a bit body being provided with at least one cutter thereon exhibiting reduced, or limited, exposure to the formation so as to control the depth-of-cut of the at least one cutter, so as to control the volume of formation material cut per bit rotation, as well as to control the amount of torque experienced by the bit and an optionally associated bottomhole assembly regardless of the effective weight-on-bit. The exterior of the bit preferably includes a plurality of blade structures carrying at least one such cutter thereon and including a sufficient amount of bearing surface area to contact the formation so as to generally distribute an additional weight applied to the bit against the bottom of the borehole without exceeding the compressive strength of the formation rock.

Abstract: A rotary drag bit and method for drilling subterranean formations including a bit body being provided with at least one cutter thereon exhibiting reduced, or limited, exposure to the formation so as to control the depth-of-cut of the at least one cutter, so as to control the volume of formation material cut per bit rotation, as well as to control the amount of torque experienced by the bit and an optionally associated bottomhole assembly regardless of the effective weight-on-bit. The exterior of the bit preferably includes a plurality of blade structures carrying at least one such cutter thereon and including a sufficient amount of bearing surface area to contact the formation so as to generally distribute the weight of the bit against the bottom of the borehole without exceeding the compressive strength of the formation rock.

Abstract: A cutting assembly comprised of first and second superabrasive cutting elements including at least one rotationally leading cutting element having a cutting face oriented generally in a direction of intended rotation of a bit on which the assembly is mounted to cut a subterranean formation with a cutting edge at an outer periphery of the cutting face, and a rotationally trailing cutting element oriented substantially transverse to the direction of intended bit rotation and including a relatively thick superabrasive table configured to cut the formation with a cutting edge located between a beveled surface at the side of the superabrasive table and an end face thereof. A rotationally trailing cutting element may be associated with and disposed at a location on the bit at least partially laterally intermediate locations of two rotationally leading cutting elements. Drill bits equipped with the cutting assembly are also disclosed.

Abstract: A cutter comprising a superabrasive volume including a cutting face portion extending transversely across a leading face of a supporting substrate and a contiguous jacket portion extending rearwardly over the supporting substrate along a portion of its side periphery. Interfaces between the respective superabrasive volume cutting face and cap portions and adjoining surfaces of the supporting substrate are each irregular. The leading face of the substrate includes grooves extending toward the jacket at least partially across the leading face from the side of the substrate opposite the jacket. The side periphery of the substrate defining the location of the jacket is grooved at a plurality of laterally-adjacent locations with substantially axially-oriented grooves extending rearwardly from the leading face of the substrate to a position closer to the trailing face of the substrate.