The invention discloses systems for improving performance and operational efficiency of wireline tractors. A cooling system improves power capabilities of electrical motors mounted in wheels, which are mounted on a linkage pivotably connected to an arm extended from a tractor tool body, in an in-line arm configuration. The linkage and arm mechanism significantly improve the tractor's ability to traverse wellbore obstructions. The hydraulic system of the tractor ensures adequate wellbore centralization.

The invention discloses systems for improving performance and operational efficiency of wireline tractors. A cooling system improves power capabilities of electrical motors mounted in wheels, which are mounted on a linkage pivotably connected to an arm extended from a tractor tool body, in an in-line arm configuration. The linkage and arm mechanism significantly improve the tractor's ability to traverse wellbore obstructions. The hydraulic system of the tractor ensures adequate wellbore centralization.

An electrical submersible well pump assembly has shaft couplings. One of the couplings has a lower hub that rotates in unison with the motor shaft and an upper hub that rotates in unison with the pump shaft. A helical spring clutch engages both hubs when the motor shaft is being driven by the motor. Ceasing driving rotation of the motor shaft causes the spring clutch to disengage from the upper hub, enabling the pump shaft to rotate the upper hub without rotating the lower hub.

An electrical submersible well pump assembly has shaft couplings. One of the couplings has a lower hub that rotates in unison with the motor shaft and an upper hub that rotates in unison with the pump shaft. A helical spring clutch engages both hubs when the motor shaft is being driven by the motor. Ceasing driving rotation of the motor shaft causes the spring clutch to disengage from the upper hub, enabling the pump shaft to rotate the upper hub without rotating the lower hub.

A system for the recirculation of gas in air gaps of rotating machines via an ejector, a motor and a pump, including circulating a gas extracted from a gas-extraction unit which is located in the pump. This gas circulates in the gap between the rotors and the stator of the motor. The rotor of the motor is coupled to the shaft of the pump, and in one or more embodiments the gas from the gas-extraction unit flows from the pump to the ejector in order to be injected into the air gap between the rotor and the stator, thereafter returning to a process line. In one or more embodiments, the gas from the gas-extraction unit flows from the pump, and is injected directly into the air gap, and thereafter passes via the ejector in order to recirculate the gas to the process line.

Systems and methods for connecting rotors between multiple permanent magnet motors. By coupling the rotors of multiple modules, torque may be transferred while maintaining the angular alignment between the stator and rotor magnetic fields of each individual permanent magnet motor.

A motor lead coupler is configured to provide a metal-to-metal sealed connection between a first motor lead extension and a second motor lead extension. The motor lead coupler includes a first plurality of receivers on a first end of the body, a second plurality of receivers on a second end of the body, and a plurality of intermediate terminals. Each of the first plurality of receivers is configured to receive a corresponding one of the first plurality of leads, and each of the second plurality of receivers is configured to receive a corresponding one of the second plurality of leads. Each of the intermediate terminals is connected between a corresponding pair of the first plurality of receivers and the second plurality of receivers. The motor lead coupler includes pressure test ports that can be used to pressure test the connection between individual leads and the motor lead coupler.

A motor lead coupler is configured to provide a metal-to-metal sealed connection between a first motor lead extension and a second motor lead extension. The motor lead coupler includes a first plurality of receivers on a first end of the body, a second plurality of receivers on a second end of the body, and a plurality of intermediate terminals. Each of the first plurality of receivers is configured to receive a corresponding one of the first plurality of leads, and each of the second plurality of receivers is configured to receive a corresponding one of the second plurality of leads. Each of the intermediate terminals is connected between a corresponding pair of the first plurality of receivers and the second plurality of receivers. The motor lead coupler includes pressure test ports that can be used to pressure test the connection between individual leads and the motor lead coupler.

An electric submersible pump assembly with integral heat exchanger, high speed gas separator, high-speed self-aligning bearings, and dual bearing thrust chamber is described. The described gas separator may be used for operating an electric submersible pump at high speeds as well as over a wide range of speeds and flowrates without replacing downhole equipment.

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.