Abstract: An operational amplifier includes an input stage configured to receive a first input voltage and a second input voltage and a slew boost circuit coupled to the input stage and configured to selectively increase current through the input stage. The operational amplifier also includes an output stage coupled to the input stage and configured to generate an output voltage, and a slew boost disable circuit configured to assert a control signal to the slew boost circuit to disable the slew boost circuit. The slew boost circuit is disabled when both: the first input voltage being more than a first threshold voltage different from the second input voltage and the output voltage failing to change by more than a second threshold rate.

Abstract: Various embodiments disclosed relate to bearing assembly for drilling a subterranean formation and methods of using the same. In various embodiments, the present invention provides a method of drilling a subterranean formation. The method includes flowing a drilling fluid through a drill string disposed in the subterranean formation, with the drill string including a bottom hole assembly including a bearing assembly including a low flow bearing. The method includes flowing a first part of the drilling fluid into contact with the low flow bearing, while simultaneously flowing a second part of the drilling fluid through a bypass channel around the low flow bearing. The method also includes discharging the first and second part of the drilling fluid between the bottom hole assembly and the subterranean formation.

Abstract: An operational amplifier includes an input stage configured to receive a first input voltage and a second input voltage and a slew boost circuit coupled to the input stage and configured to selectively increase current through the input stage. The operational amplifier also includes an output stage coupled to the input stage and configured to generate an output voltage, and a slew boost disable circuit configured to assert a control signal to the slew boost circuit to disable the slew boost circuit. The slew boost circuit is disabled when both: the first input voltage being more than a first threshold voltage different from the second input voltage and the output voltage failing to change by more than a second threshold rate.

Abstract: A downhole drilling motor, system, and method for using same are disclosed. A downhole drilling motor can include a power section stator having a first end, a second end, an internal cavity passing therethrough. The downhole drilling motor can further include a rotor assembly positioned and fully encased in the internal cavity. The rotor assembly includes a power section rotor, a drivetrain operably coupled to the power section rotor and a bearing set. The power section rotor is positioned at the first end within the internal cavity of the power section stator. The power section rotor, the drivetrain, and the bearing set are fully encased in the internal cavity of the power section stator. Additional apparatuses, systems, and methods are disclosed.

Abstract: Downhole tools such as bearing assemblies and stabilizers are described for withstanding abrasive and erosive wear in operation. These stabilizers and bearing assemblies employ wear-resistant hard materials such as TSP, PCD, leached WC, and SCD composite materials. A bond between a braze material and wear tiles constructed of a hard phase material may include a non-planar interface with the braze material. Self-lubricating materials may be provided within the braze material or the hard material in some instances.

Abstract: A stabilizer device is provided for a mud motor drilling assembly. The stabilizer device may be mounted to a motor housing having one or more grooves or ridges. The stabilizer device may include a stabilizer body, a threader portion, and a clamp. The threaded portion may be positioned between the one or more grooves or ridges and the clamp. The threaded portion may include an external surface having threads. The threads on the external surface of the threaded portion of the stabilizer device may correspond to threads on an internal surface of a clamp. The threaded coupling of the clamp to the stabilizer device may couple the stabilizer device to the motor housing at the one or more grooves or ridges.

Abstract: A bearing assembly for a downhole drilling motor can include a housing having an inner wall, an outer bearing race within the housing, and an inner bearing race. The outer bearing race can include a reduced-diameter portion forming a gap between the outer bearing race and the inner wall of the housing to allow for radial displacement of the outer bearing race relative to the housing. The design combines the functions of a bearing and a compliant feature into a single unit. The design will also provide reliability of performance in high dogleg and short bit-to-bend applications where radial loads are extreme and bearings frequently fail.

Abstract: A drilling apparatus including a tubular bearing housing, a tilted sleeve removably connected with the bearing housing, and a driveshaft. The bearing housing has a housing axis, a housing bore, and a housing bore axis. The housing bore axis is parallel with the housing axis. The tilted sleeve has a sleeve axis, a sleeve bore, and a sleeve bore axis. The tilted sleeve is connected with the bearing housing and is positioned within the housing bore. The sleeve axis is parallel with the housing bore axis and the sleeve bore axis is oblique to the sleeve axis. The driveshaft is rotatably supported within the sleeve bore. The driveshaft has a driveshaft axis. The driveshaft axis is parallel with the sleeve bore axis.

Abstract: A radial bearing for transmitting a radial load, including a first radial bearing component defining a first radial bearing surface and an orientable second radial bearing component defining a second radial bearing surface. At least a portion of the first radial bearing surface is provided by a first radial bearing material. A portion of the second radial bearing surface is provided by a second radial bearing material. The first radial bearing component and the second radial bearing component interact to transmit the radial load between the first radial bearing component and the second radial bearing component at a radial load location on the second radial bearing component. The second radial bearing material is provided as the portion of the second radial bearing surface such that the second radial bearing material is concentrated at the radial load location.

Abstract: A shank comprises a captive portion, comprising a longitudinal central axis, a captive end, a first set of first structures, and a second set of second structure. The second set of the second structures is closer to the captive end than the first set of the first structures. The first set of the first structures has a first axial compliance coefficient along the longitudinal central axis. The second set of the second structures has a second axial compliance coefficient along the longitudinal central axis. The first axial compliance coefficient of the first set of the first structures is greater than the second axial compliance coefficient of the second set of the second structures.

Abstract: A method of forming a shank comprises arranging first structures in a first set of the first structures and second structures in a second set of the second structures such that the first structures and the second structures extend away from a longitudinal central axis in a direction normal to the longitudinal central axis and such that ends of the first structures and the second structures, farthest away from the longitudinal central axis, form cylindrical surfaces, parallel to the longitudinal central axis and equidistant from the longitudinal central axis. The method further comprises indirectly bonding the first set of the first structures to the second set of the second structures, thereby forming the shank. At least one of the first structures consists of a first material. At least one of the second structures consists of a second material, such that the first material is different from the second material.

Abstract: A driveshaft transmission assembly may include a catch assembly. The catch assembly may prevent the loss of certain driveshaft transmission assembly components downhole in the event of a failure of the driveshaft transmission due to dynamic loads produced during operation of a drilling system. The catch assembly may be coupled to a first radial bearing assembly using locking devices. The driveshaft transmission assembly may also include a second radial bearing assembly interlockably coupled to a thrust bearing and a bearing housing.

Abstract: A method of forming a receiver 130 comprises arranging first structures 120a in a first set 117 and second structures 120b in a second set 119 such that the first structures 120a and the second structures 120b extend within an interior space 136 of the receiver 130 in a direction normal to a longitudinal central axis 112 of the interior space 136. The method further comprises indirectly bonding the first set 117 of the first structures 120a to the second set 119 of the second structures 120b.

Abstract: A receiver comprises an interior space comprising a longitudinal central axis and a receiving end, a first set of first structures, and a second set of second structures. The first set of the first structures is positioned closer to the receiving end of the interior space than the second set of the second structures. The first set of the first structures has a first axial compliance coefficient along the longitudinal central axis of the interior space. The second set of the second structures has a second axial compliance coefficient along the longitudinal central axis of the interior space, such that the first axial compliance coefficient is greater than the second axial compliance coefficient.

Abstract: An assembly for use in a wellbore can include a drill string having an outer housing and a thrust bearing sleeve positioned within the outer housing of the drill string. The assembly can also include a stationary thrust bearing positioned within the thrust bearing sleeve and coaxially around a mandrel extending through a longitudinal length of the thrust bearing sleeve. The assembly can further include an interlocking component including a first end coupled to the stationary thrust bearing and a second end positioned in a recessed portion of a housing of the drill string for preventing the stationary thrust bearing from rotating about a central axis of the mandrel, and for allowing the stationary thrust bearing to rotate about one or more axes perpendicular to the central axis. The assembly can include a flexible member for opposing a rotational force applied to the stationary thrust bearing by another thrust bearing.

Abstract: A stabilizer device is provided for a mud motor drilling assembly. The stabilizer device may be mounted to a motor housing having one or more grooves or ridges. The stabilizer device may include a stabilizer body, a threaded portion, and a clamp. The threaded portion may be positioned between the one or more grooves or ridges and the clamp. The threaded portion may include an external surface having threads. The threads on the external surface of the threaded portion of the stabilizer device may correspond to threads on an internal surface of a clamp. The threaded coupling of the clamp to the stabilizer device may couple the stabilizer device to the motor housing at the one or more grooves or ridges.

Abstract: A drilling apparatus including a tubular bearing housing, a tilted sleeve removably connected with the bearing housing, and a driveshaft. The bearing housing has a housing axis, a housing bore, and a housing bore axis. The housing bore axis is parallel with the housing axis. The tilted sleeve has a sleeve axis, a sleeve bore, and a sleeve bore axis. The tilted sleeve is connected with the bearing housing and is positioned within the housing bore. The sleeve axis is parallel with the housing bore axis and the sleeve bore axis is oblique to the sleeve axis. The driveshaft is rotatably supported within the sleeve bore. The driveshaft has a driveshaft axis. The driveshaft axis is parallel with the sleeve bore axis.

Abstract: A clamping assembly may include a split-ring device and bearing for coupling to a driveshaft. The split-ring device may comprise split-ring shells having protrusions on an interior radial surface for positioning in grooves adjacent to radial protrusions on the driveshaft. In some aspects, the split-ring shells may include tabs corresponding to cavities on a first bearing for coupling the split-ring shell to the first bearing. In other aspects, the split-ring shells may be sized to create one or more gaps when positioned on the driveshaft. The first bearing may include one or more corresponding tabs for positioning in the one or more gaps created by the split-ring shells. A second bearing may be threadably coupled to the first bearing to suppress the axial and rotational movement of the clamping assembly separate from the driveshaft.

Abstract: A differential input circuit (FIG. 3A) is disclosed. The circuit includes a first input terminal (drain of 310) and a second input terminal (drain of 312). A first input transistor (310) has a first control terminal and has a current path coupled to the first input terminal. A second input transistor (312) has a second control terminal and has a current path coupled to the second input terminal. A third transistor (306) has a third control terminal and has a current path between a first differential input terminal (Vin+) and the first control terminal. A fourth transistor (308) has a fourth control terminal and has a current path between a second differential input terminal (Vin?) and the second control terminal.

Abstract: An interference apparatus is provided for a motor shaft transmission assembly. The interference apparatus may include split-ring shells and a retaining device. The interference apparatus may be mounted to an intermediate sleeve of the motor shaft transmission assembly. The interference apparatus is configured to prevent the loss of certain motor shaft transmission assembly components downhole in the event of a failure of the motor transmission due to dynamic loads.