Abstract: A transmission assembly includes a cavity in a female U-joint having a groove that extends radially outward from an inner diameter thereof and bounded by three planar drive surfaces. A male U-joint member includes a drive end includes a longitudinal rectangular extension protruding radially outward from a periphery and positioned within the groove of the cavity. The drive end includes a longitudinal rectangular insert has a portion forming the extension positioned within the groove and retained within the drive end. The extension includes (1) opposing longitudinal sides, each forming a side crest disposed between a pair of angular side surfaces that extend axially from the side crest inward toward a center of the extension, and (2) a top side forming a top crest disposed between a pair of angular top surfaces that extend axially from the top crest downward toward the center of the extension.

Abstract: A universal joint (U-joint) assembly transmits torque from a drive component to a driven component across an articulating joint. The U-joint assembly includes male and female U-joint members, a central ball joint, and a retaining device configured to secure the assembly in an assembled configuration. The female U-joint member includes a cavity extending into a receptacle end thereof. The cavity terminates in a circular receptacle and includes a plurality of rectangular channels extending radially outward from the cavity at equal intervals, each channel defined by three planar drive surfaces. The male U-joint member has a drive end with a plurality of corresponding rectangular extensions protruding from an outer periphery of the drive end, each extension including a plurality of axial angular surfaces. When assembled, each of the angular surfaces of the drive end opposes a corresponding one of the drive surfaces of the cavity. Other embodiments are also disclosed.

Abstract: A universal joint (U-joint) assembly transmits torque from a drive component to a driven component across an articulating joint. The U-joint assembly includes male and female U-joint members, a central ball joint, and a retaining device configured to secure the assembly in an assembled configuration. The female U-joint member includes a cavity extending into a receptacle end thereof. The cavity terminates in a circular receptacle and includes a plurality of rectangular channels extending radially outward from the cavity at equal intervals, each channel defined by three planar drive surfaces. The male U-joint member has a drive end with a plurality of corresponding rectangular extensions protruding from an outer periphery of the drive end, each extension including a plurality of axial angular surfaces. When assembled, each of the angular surfaces of the drive end opposes a corresponding one of the drive surfaces of the cavity. Other embodiments are also disclosed.

Abstract: A universal joint (U-joint) assembly transmits torque from a drive component to a driven component across an articulating joint. The U-joint assembly includes male and female U-joint members, a central ball joint, and a retaining device configured to secure the assembly in an assembled configuration. The female U-joint member includes a cavity extending into a receptacle end thereof. The cavity terminates in a circular receptacle and includes four flat surfaces extending longitudinally therefrom at 90-degree intervals. The male U-joint member has a drive end with four multi-angled surfaces extending longitudinally from the drive end at 90-degree intervals about a periphery of the drive end. When in an assembled configuration, each of the multi-angled surfaces of the drive end of the male U-joint member opposes a corresponding one of the four flat surfaces of cavity of the female U-joint member. Other embodiments are also disclosed.

Abstract: A rotatable bearing assembly transfers a weight of a drill string to a mud motor output shaft extending therethrough. The bearing assembly includes an outer bearing housing, an upper radial bearing assembly providing an upper radial bearing between the outer bearing housing and the output shaft, a balance piston that fluidly seals an upper end of the outer bearing housing and balances a pressure within the outer bearing housing, a lower radial bearing/seal assembly configured to both fluidly seal a lower end of the outer bearing housing and provide a lower radial bearing between the outer bearing housing and the output shaft, and a thrust bearing assembly received within the sealed interior of the outer bearing housing such that the bearing assembly initially operates in a sealed, lubricated mode and then a mud lube mode in the event of one or more seal failures. Other embodiments are also disclosed.

Abstract: A rotatable bearing assembly transfers a weight of a drill string to a mud motor output shaft extending therethrough. The bearing assembly includes an outer bearing housing, an upper radial bearing assembly providing an upper radial bearing between the outer bearing housing and the output shaft, a balance piston that fluidly seals an upper end of the outer bearing housing and balances a pressure within the outer bearing housing, a lower radial bearing/seal assembly configured to both fluidly seal a lower end of the outer bearing housing and provide a lower radial bearing between the outer bearing housing and the output shaft, and a thrust bearing assembly received within the sealed interior of the outer bearing housing such that the bearing assembly initially operates in a sealed, lubricated mode and then a mud lube mode in the event of one or more seal failures. Other embodiments are also disclosed.

Abstract: A universal joint (U-joint) assembly transmits torque from a drive component to a driven component across an articulating joint. The U-joint assembly includes male and female U-joint members, a central ball joint, and a retaining device configured to secure the assembly in an assembled configuration. The female U-joint member includes a cavity extending into a receptacle end thereof. The cavity terminates in a circular receptacle and includes a plurality of rectangular channels extending radially outward from the cavity at equal intervals, each channel defined by three planar drive surfaces. The male U-joint member has a drive end with a plurality of corresponding rectangular extensions protruding from an outer periphery of the drive end, each extension including a plurality of axial angular surfaces. When assembled, each of the angular surfaces of the drive end opposes a corresponding one of the drive surfaces of the cavity. Other embodiments are also disclosed.

Abstract: A universal joint (U-joint) assembly transmits torque from a drive component to a driven component across an articulating joint. The U-joint assembly includes male and female U-joint members, a central ball joint, and a retaining device configured to secure the assembly in an assembled configuration. The female U-joint member includes a cavity extending into a receptacle end thereof. The cavity terminates in a circular receptacle and includes four flat surfaces extending longitudinally therefrom at 90-degree intervals. The male U-joint member has a drive end with four multi-angled surfaces extending longitudinally from the drive end at 90-degree intervals about a periphery of the drive end. When in an assembled configuration, each of the multi-angled surfaces of the drive end of the male U-joint member opposes a corresponding one of the four flat surfaces of cavity of the female U-joint member. Other embodiments are also disclosed.

Abstract: The disclosure provides a system and process for drilling a subterranean wellbore. An embodiment includes a bottom-hole assembly for a downhole mud motor that incorporates an information sub, such as a measurement-while-drilling or logging-while-drilling tool, at a location below, or down-hole from, the mud motor. The assembly also includes a micronized bit-to-bend length, or a length between a forward end of the assembly's bearing mandrel and a fixed bend in the assembly's housing, of less than or equal to forty inches. The combination of the forward-located information sub and micronized bit-to-bend length allow the driller to rely on real-time data relating to conditions adjacent to the drill bit/bottom of the wellbore and take that real-time drilling data into account in steering the bit along a planned wellbore trajectory. Other embodiments are also disclosed.

Abstract: The disclosure provides a system and process for drilling a subterranean wellbore. An embodiment includes a bottom-hole assembly for a downhole mud motor that incorporates an information sub, such as a measurement-while-drilling or logging-while-drilling tool, at a location below, or down-hole from, the mud motor. The assembly also includes a micronized bit-to-bend length, or a length between a forward end of the assembly's bearing mandrel and a fixed bend in the assembly's housing, of less than or equal to forty inches. The combination of the forward-located information sub and micronized bit-to-bend length allow the driller to rely on real-time data relating to conditions adjacent to the drill bit/bottom of the wellbore and take that real-time drilling data into account in steering the bit along a planned wellbore trajectory. Other embodiments are also disclosed.