An electric submersible pump (ESP) assembly. The ESP assembly comprises a centrifugal pump, an electric motor mechanically coupled by a drive shaft to the centrifugal pump, wherein the electric motor comprises a stator and a rotor, a bearing, wherein the bearing is disposed inside the electric motor, and a magnetic shield disposed in the electric motor between bearing and the rotor and stator.

A motor comprising: (a) a stator having a plurality of ferrous cores surrounded by a plurality of windings; (b) a pair of rotors positioned on opposing sides of the stator, each rotor including a ring gear; and (c) a drive shaft extending through a cutout of the stator, the drive shaft having a pinion gear positioned near an end of the drive shaft in communication with the ring gears of the rotors; wherein the rotors rotate in opposing directions so that the ring gears translate a movement of the rotors to the drive shaft through the pinion gear to rotate the drive shaft in a direction substantially orthogonal to a direction of rotation of the rotors.

A motor comprising: (a) a stator having a plurality of ferrous cores surrounded by a plurality of windings; (b) a pair of rotors positioned on opposing sides of the stator, each rotor including a ring gear; and (c) a drive shaft extending through a cutout of the stator, the drive shaft having a pinion gear positioned near an end of the drive shaft in communication with the ring gears of the rotors; wherein the rotors rotate in opposing directions so that the ring gears translate a movement of the rotors to the drive shaft through the pinion gear to rotate the drive shaft in a direction substantially orthogonal to a direction of rotation of the rotors.

A stator for a downhole-type motor includes a housing. The housing includes a sleeve. The sleeve includes a first layer, a second layer, and a third layer. The first layer is erosion-resistant. The second layer is corrosion-resistant. The third layer can provide structural support. The stator includes a motor stack. The stator can be used to drive a rotor disposed within an inner bore of the housing.

A stator for a downhole-type motor includes a housing. The housing includes a sleeve. The sleeve includes a first layer, a second layer, and a third layer. The first layer is erosion-resistant. The second layer is corrosion-resistant. The third layer can provide structural support. The stator includes a motor stack. The stator can be used to drive a rotor disposed within an inner bore of the housing.

An electrical submersible well pump assembly has first and second permanent magnet motors. The first motor drive shaft is connected to a coupling that has internal splines for receiving an externally splined end of the second motor drive shaft. Alignment devices rotationally align magnetic poles of the first drive shaft with the magnetic poles of the second drive shaft prior to securing the housings of the first and second motors together. The alignment devices may be a coupling irregularity in the internal splines that is at a controlled orientation relative to the magnetic poles of the first shaft and a shaft irregularity in the external splines that prevents the second drive shaft from fully engaging the coupling unless the shaft irregularity is in a specified rotational position relative to the coupling irregularity.

An electrical submersible well pump assembly has first and second permanent magnet motors. The first motor drive shaft is connected to a coupling that has internal splines for receiving an externally splined end of the second motor drive shaft. Alignment devices rotationally align magnetic poles of the first drive shaft with the magnetic poles of the second drive shaft prior to securing the housings of the first and second motors together. The alignment devices may be a coupling irregularity in the internal splines that is at a controlled orientation relative to the magnetic poles of the first shaft and a shaft irregularity in the external splines that prevents the second drive shaft from fully engaging the coupling unless the shaft irregularity is in a specified rotational position relative to the coupling irregularity.

An electrical submersible pump (ESP) including a motorized pump having a motor and a pump and that may be employed in a wellbore. The pump rotor has vanes and the pump stator has vanes. The pump rotor is integrated with the motor rotor, wherein the pump rotor and the motor rotor rotate together.

An electrical submersible pump (ESP) including a motorized pump having a motor and a pump and that may be employed in a wellbore. The pump rotor has vanes and the pump stator has vanes. The pump rotor is integrated with the motor rotor, wherein the pump rotor and the motor rotor rotate together.

A sea scooter has a main housing, a left arm pivotably attached to the left side of the main housing, a right arm pivotably attached to the right side of the main housing, a left barrel secured to the left arm, and a right barrel secured to the right arm. Each barrel has a fan and a motor for propelling the sea scooter through water. The left and right arms are locked by the first and second locking assemblies into a folded configuration against the left and right sides of the main housing when the sea scooter is not in use, and the left and right arms are pivoted away from the left and right sides of the main housing in a use configuration when the sea scooter is in use in the water. The motor is sand-proof and water-proof.