Abstract: A top drive for well operations having a gearbox, a traction motor connected to the gearbox so that a motor shaft of the traction motor extends into the gearbox, a quill extending into the gearbox, a gear train positioned within the gearbox and mechanically connected between the traction motor shaft and the quill, and a connector positioned in the gear train, wherein in a coupled configuration the connector communicates torque through the gear train, and wherein in a decoupled configuration the connector does not communicate torque through the gear train. A method for operating a top drive by applying a first torque to a quill with two traction motors, disconnecting one of the traction motors from the quill, and applying a second torque less than the first torque to the quill with the non-disconnected traction motor.

Abstract: A top drive for well operations having a gearbox, a traction motor connected to the gearbox so that a motor shaft of the traction motor extends into the gearbox, a quill extending into the gearbox, a gear train positioned within the gearbox and mechanically connected between the traction motor shaft and the quill, and a connector positioned in the gear train, wherein in a coupled configuration the connector communicates torque through the gear train, and wherein in a decoupled configuration the connector does not communicate torque through the gear train. A method for operating a top drive by applying a first torque to a quill with two traction motors, disconnecting one of the traction motors from the quill, and applying a second torque less than the first torque to the quill with the non-disconnected traction motor.

Abstract: A top drive for well operations having a gearbox, a traction motor connected to the gearbox so that a motor shaft of the traction motor extends into the gearbox, a quill extending into the gearbox, a gear train positioned within the gearbox and mechanically connected between the traction motor shaft and the quill, and a connector positioned in the gear train, wherein in a coupled configuration the connector communicates torque through the gear train, and wherein in a decoupled configuration the connector does not communicate torque through the gear train. A method for operating a top drive by applying a first torque to a quill with two traction motors, disconnecting one of the traction motors from the quill, and applying a second torque less than 50% of the first torque to the quill with the non-disconnected traction motor.

Abstract: A positive displacement pump of this disclosure includes a plain bearing comprising a composite material located between a first component that may experience an oscillating motion at low speed (or at low speed and high loads) and a second component located about the first. The pump may be a mud pump configured to circulate a drilling fluid into and out of a well bore during an oil/gas well drilling operation. The first component may be a wrist pin of a crosshead and the second component may be an end of a connecting rod. The composite material may be a bearing grade material that is self-lubricating and wet or contaminant tolerant or resistant. The composite material may include polyketone. In retrofit or new applications, the plain bearing may include a sleeve containing a liner made of the composite material. No external lubrication may be required, eliminating the need for lubricating structures.

Abstract: A system includes a first transmission having a first planetary gearset, a first drive shaft, and a first annular sleeve. The first annular sleeve is positioned circumferentially about the first drive shaft, and the first annular sleeve is configured to move axially relative to the first drive shaft and the first planetary gearset from a first axial position in which the first annular sleeve engages a first sun gear of the first planetary gearset to a second axial position in which the first annular sleeve engages a first ring gear of the first planetary gearset to adjust a gear ratio of the first transmission.

Abstract: A system includes a first transmission having a first planetary gearset, a first drive shaft, and a first annular sleeve. The first annular sleeve is positioned circumferentially about the first drive shaft, and the first annular sleeve is configured to move axially relative to the first drive shaft and the first planetary gearset from a first axial position in which the first annular sleeve engages a first sun gear of the first planetary gearset to a second axial position in which the first annular sleeve engages a first ring gear of the first planetary gearset to adjust a gear ratio of the first transmission.

Abstract: A position sensor system is useful for monitoring positions of shifters in transmissions and other applications. The position sensing system has an array of magneto resistive sensors and a controller configured to determine a position of a magnet along a path by triangulation. Some embodiments are relatively insensitive to fluctuations in a distance between the sensors and the path. Also described is an actuating assembly comprising a movable cylinder and a fixed rod. The actuating assembly may be applied for moving synchronizers or the like in power transmissions.

Abstract: A dual clutch type transmission has first and second sections which respectively include first and second clutches. The clutches may be operated to allow torque transfer from an input to an output by way of the first section or the second section. One or more additional gear ratios is provided by a torque transfer pathway connecting the first and second sections such that torque is delivered from the input to the output by way of one or more stages of the first section and one or more stages of the second section. The additional gear ratios may comprise extra low gear ratios. Some embodiments provide transmissions suitable for driving pumps for use in hydraulic fracturing of geological formations.

Abstract: A position sensor system is useful for monitoring positions of shifters in transmissions and other applications. The position sensing system has an array of magneto resistive sensors and a controller configured to determine a position of a magnet along a path by triangulation. Some embodiments are relatively insensitive to fluctuations in a distance between the sensors and the path. Also described is an actuating assembly comprising a movable cylinder and a fixed rod. The actuating assembly may be applied for moving synchronizers or the like in power transmissions.

Abstract: A dual clutch type transmission has first and second sections which respectively include first and second clutches. The clutches may be operated to allow torque transfer from an input to an output by way of the first section or the second section. One or more additional gear ratios is provided by a torque transfer pathway connecting the first and second sections such that torque is delivered from the input to the output by way of one or more stages of the first section and one or more stages of the second section. The additional gear ratios may comprise extra low gear ratios. Some embodiments provide transmissions suitable for driving pumps for use in hydraulic fracturing of geological formations.