Abstract: A cable system for use downhole includes a connector assembly having a body and a bore formed therethrough; a conductor disposed through the bore of the connector assembly; and a first insulation layer disposed around the conductor. An insulator tube is disposed around the conductor and has an end attached to the first insulation layer. The insulator tube may be made of a thermoplastic material. A graphite containing sealing member is disposed in the bore and disposed between the insulator tube and the body of the connector assembly.

Abstract: The invention relates to the field of electrical engineering, in particular the design of linear electric motors for submersible installations with a plunger pump, and used for oil extraction. The technical result is to increase the durability of the submersible electric motor and the efficiency of its operation. The stator consists of a cylindrical housing, within which are installed magnetically conductive cups incorporating armature coils and support elements separating the groups of cups, whereby the inner diameter of which is less than the inner diameter of the magnetically conductive cups. On the inner surface of the support elements, grooves are provided, the depth of which is more than half the difference between the inner diameters of the magnetically conductive cups and the support elements. Moreover, the magnetically conductive cups and the support elements are installed in a housing with a radial clearance and are attached therein by fastening elements.

Abstract: A downhole assembly of an artificial lift system includes: an adapter for connection to production tubing; a receptacle shaft; an up-thrust bearing; a centrifugal pump; and a down-thrust bearing. The receptacle shaft has a latch profile for receiving a latch fastener of a drive coupling and a torsional profile for mating with the coupling to longitudinally and torsionally connect thereto. The up-thrust bearing includes: a thrust driver longitudinally and torsionally connected to the receptacle shaft; and a thrust carrier connected to the adapter. The centrifugal pump includes: a diffuser connected to the adapter; a pump shaft torsionally connected to the receptacle shaft; and an impeller connected to the pump shaft. The down-thrust bearing includes: a thrust driver longitudinally and torsionally connected to the pump shaft; and a thrust carrier connected to the adapter.

Abstract: A surface mounted pump assembly includes a centrifugal pump having a plurality of impellers and an electric motor adapted to drive the pump such that a thrust load from the pump is transmitted to the motor.

Abstract: A thermal compensator for a motor seal, includes: a guide tube for receiving a shaft of the motor seal; a metallic bag disposed around the guide tube and having an expansion profile formed in at least a portion thereof to accommodate radial and circumferential expansion of the metallic bag; a pair of flanges attached to opposite ends of the metallic bag; and a pair of adapters fastened to the respective flanges and receiving respective ends of the guide tube.

Abstract: A downhole assembly of an artificial lift system includes: an adapter for connection to production tubing; a receptacle shaft; an up-thrust bearing; a centrifugal pump; and a down-thrust bearing. The receptacle shaft has a latch profile for receiving a latch fastener of a drive coupling and a torsional profile for mating with the coupling to longitudinally and torsionally connect thereto. The up-thrust bearing includes: a thrust driver longitudinally and torsionally connected to the receptacle shaft; and a thrust carrier connected to the adapter. The centrifugal pump includes: a diffuser connected to the adapter; a pump shaft torsionally connected to the receptacle shaft; and an impeller connected to the pump shaft. The down-thrust bearing includes: a thrust driver longitudinally and torsionally connected to the pump shaft; and a thrust carrier connected to the adapter.

Abstract: A surface mounted pump assembly includes a centrifugal pump having a plurality of impellers and an electric motor adapted to drive the pump such that a thrust load from the pump is transmitted to the motor.

Abstract: A rotor for a submersible motor includes a shaft and a hub. The hub is: disposed around the shaft, torsionally connected to the shaft, and made from a magnetically permeable metal or alloy. The rotor further includes permanent magnets disposed around the hub; and a polymer shroud encapsulating the permanent magnets and molded to the hub.

Abstract: A method for pumping production fluid from a wellbore includes deploying a downhole assembly of an artificial lift system (ALS) into the wellbore. The downhole assembly includes a linear electric motor (LEM) and a pump. The method further includes operating the LEM, thereby reciprocating the pump and lifting production fluid from the wellbore to surface. The LEM includes a stator and a reciprocating head having permanent magnets. The production fluid leaks through an interface formed between the head and the stator.

Abstract: A method of pumping production fluid from a wellbore includes deploying a centrifugal pump into a production wellbore; and pumping hydrocarbons from the production wellbore by rotating an impeller of the centrifugal pump in the production wellbore from surface using a drive string, wherein the impeller is rotated at a speed less than or equal to seventeen hundred fifty revolutions per minute.

Abstract: A thermal compensator for a motor seal, includes: a guide tube for receiving a shaft of the motor seal; a metallic bag disposed around the guide tube and having an expansion profile formed in at least a portion thereof to accommodate radial and circumferential expansion of the metallic bag; a pair of flanges attached to opposite ends of the metallic bag; and a pair of adapters fastened to the respective flanges and receiving respective ends of the guide tube.

Abstract: This invention relates to a power line communication (PLC) system wherein the power supply line supplies power and also acts as a communications supply line. A receiver is able to detect small changes in the modulated transmitted information and thereby shut down the circuit. The invention is particularly suitable for use where the IEL is remote from the power supply such as, for example, in down hole oil production situations where very long power cables are used.

Abstract: An electric submersible pump contains an AC permanent magnet motor having three or more phases A, B, C and has a drive circuit for supplying varying drive signals to all the phases of the motor at the same time. Each drive signal is constituted by a cyclically smoothly varying voltage applied to the corresponding motor phase during driving of the motor. The circuit includes switches (902, 903) for each motor phase, a control arrangement for turning the switches (902, 903) on and off at a frequency greater than the frequency of the cyclically smoothly varying voltages, and a filter (907, 908) for filtering the output voltages of the switches (902, 903) to produce the cyclically smoothly varying voltages. Such a drive circuit drives all the phases of the motor continuously such that damaging transients will not arise and without requiring the motor emf or drive signals to be sinusoidal.

Abstract: This invention relates to a power line communication (PLC) system wherein the power supply line supplies power and also acts as a communications supply line. A receiver is able to detect small changes in the modulated transmitted information and thereby shut down the circuit. The invention is particularly suitable for use where the IEL is remote from the power supply such as, for example, in down hole oil production situations where very long power cables are used.

Abstract: A method for pumping production fluid from a wellbore includes deploying a downhole assembly of an artificial lift system (ALS) into the wellbore. The downhole assembly includes a linear electric motor (LEM) and a pump. The method further includes operating the LEM, thereby reciprocating the pump and lifting production fluid from the wellbore to surface. The LEM includes a stator and a reciprocating head having permanent magnets. The production fluid leaks through an interface formed between the head and the stator.

Abstract: A surface mounted pump assembly includes a centrifugal pump having a plurality of impellers and an electric motor adapted to drive the pump such that a thrust load from the pump is transmitted to the motor.

Abstract: In one embodiment, a pump assembly for pumping a wellbore fluid in a wellbore includes a pump, a fluid separator, a motor for driving the pump, and a shroud disposed around the fluid separator for guiding a gas stream leaving the fluid separator, wherein the gas stream is prevented from mixing with fluids in the wellbore.

Abstract: The invention relates to electric engineering, in particular to methods for controlling an ac electronic motor. The inventive control method consists in starting and rotating a rotor upon EMF signals in current-free sections of an armature winding, in converting the EMF signals into discrete logical level signals by a normalizer, in detecting switching points by means of a microcontroller and in displacing said points according to a load current quantity, the rotor speed of rotation and the inductance of the armature winding sections, wherein the switching points are calculated and displaced with respect to bridging times of the free sections EMF whose voltage levels are different from zero. The inventive device is characterized in that it comprises a reference level displacing unit (26), which is arranged in the normalizer between a divider 22 and a comparator unit (23) and which consists of a current sensor (27), a voltage sensor (27), two adders (29, 30) and an inverter (31).

Abstract: A method of pumping wellbore fluid, comprising the steps of: installing an electric submersible pump in a wellbore; and operating the pump at more than 4,500 rpm to pump the wellbore fluid. Pumping in this manner provides a number of advantages in use in that the required high-speed motor and pump is shorter for a given power than existing arrangements, and provides increased reliability due to reduced complexity. A much shorter motor/pump combination also allows such equipment to be used in deviated boreholes with a reduction in damage due to mishandling and bending, as well as facilitating assembly and testing in the manufacturer's plant.

Abstract: A downhole electric motor for a submersible pump has at least three phases and comprises a permanent magnet rotor and a stator bearing phase windings A, B and C in slots (2206) in the stator. Each phase winding A, B, C incorporates a coil extending through a respective pair of adjacent stator slots (2206) and surrounds a respective portion of the stator between the slots (2206). Furthermore adjacent coils of each pair of phase windings A, B, C extend through opposite parts of a respective one of the slots (2206), so that these coils extend alongside one another in the slot, either being separated by a gap through which cooling fluid may be pumped to cool the coils, or being separated by a thermally conductive projection (3110), with which the coils are in thermal contact, extending at least part of the way across the slot. Such a winding arrangement is advantageous in ensuring that the motor has a long life.