Abstract: Systems and methods for preventing rotation of an ESP motor when the motor is not powered on, thereby preventing the motor from acting as a generator when fluid flowing through the pump section of the ESP applies a torque to the motor. In one embodiment, an ESP has a motor section, a pump section. The ESP may include a directional coupling that allows unidirectional rotation between the motor shaft and a pump shaft of the pump section, and a directional lock that allows unidirectional rotation between the motor shaft and a housing of the motor section. The directional coupling and directional lock allow the pump shaft to freewheel in the forward direction without causing the motor shaft to rotate, and prevent the pump shaft and motor from rotating in the reverse direction.

Abstract: Systems and methods for preventing rotation of an ESP motor when the motor is not powered on, thereby preventing the motor from acting as a generator when fluid flowing through the pump section of the ESP applies a torque to the motor. In one embodiment, an ESP has a motor section, a pump section. The ESP may include a directional coupling that allows unidirectional rotation between the motor shaft and a pump shaft of the pump section, and a directional lock that allows unidirectional rotation between the motor shaft and a housing of the motor section. The directional coupling and directional lock allow the pump shaft to freewheel in the forward direction without causing the motor shaft to rotate, and prevent the pump shaft and motor from rotating in the reverse direction.

Abstract: Systems and methods for reclaiming and remagnetizing permanent magnet motors such as may be used in electric submersible pumps. In one embodiment, a method includes removing a permanent magnet rotor assembly from a motor and heating the rotor to burn off the residual oil and evaporate water in between laminations of the rotor and on the rotor surface. The rotor should be heated to a temperature that is above a flashpoint of oil on the rotor and below a Curie temperature of a material of a set of permanent magnets in the rotor (e.g., at least 600° F. for at least 12 hours). The heating may partially or fully demagnetize the permanent magnets in the rotor. The exposed surfaces of the rotor are then cleaned and the permanent magnets in the rotor are remagnetized using a specialized magnetizing fixture.

Abstract: Systems and methods for reclaiming and remagnetizing permanent magnet motors such as may be used in electric submersible pumps. In one embodiment, a method includes removing a permanent magnet rotor assembly from a motor and heating the rotor to burn off the residual oil and evaporate water in between laminations of the rotor and on the rotor surface. The rotor should be heated to a temperature that is above a flashpoint of oil on the rotor and below a Curie temperature of a material of a set of permanent magnets in the rotor (e.g., at least 600° F. for at least 12 hours). The heating may partially or fully demagnetize the permanent magnets in the rotor. The exposed surfaces of the rotor are then cleaned and the permanent magnets in the rotor are remagnetized using a specialized magnetizing fixture.

Abstract: Systems and methods for reclaiming and remagnetizing permanent magnet motors such as may be used in electric submersible pumps. In one embodiment, a method includes removing a permanent magnet rotor assembly from a motor and heating the rotor to burn off the residual oil and evaporate water in between laminations of the rotor and on the rotor surface. The rotor should be heated to a temperature that is above a flashpoint of oil on the rotor and below a Curie temperature of a material of a set of permanent magnets in the rotor (e.g., at least 600° F. for at least 12 hours). The heating may partially or fully demagnetize the permanent magnets in the rotor. The exposed surfaces of the rotor are then cleaned and the permanent magnets in the rotor are remagnetized using a specialized magnetizing fixture.

Abstract: Systems and methods for preventing rotation of an ESP motor when the motor is not powered on, thereby preventing the motor from acting as a generator when fluid flowing through the pump section of the ESP applies a torque to the motor. In one embodiment, an ESP has a motor section, a pump section. The ESP may include a directional coupling that allows unidirectional rotation between the motor shaft and a pump shaft of the pump section, and a directional lock that allows unidirectional rotation between the motor shaft and a housing of the motor section. The directional coupling and directional lock allow the pump shaft to freewheel in the forward direction without causing the motor shaft to rotate, and prevent the pump shaft and motor from rotating in the reverse direction.

Abstract: An electrical submersible pumping (ESP) system can include a pump located in a wellbore, a motor attached to the pump, a power source located at the surface, a cable electrically coupling the power source and the motor, and a current sensor. The ESP system can also include a controller communicating with the current sensor to calculate a voltage drop associated with the cable responsive to an impedance of the cable. The controller can also control a power source output voltage responsive to the calculated voltage drop. For example, the controller can adjust the power source output voltage to minimize a cable current while maintaining a minimum motor voltage. The controller can also control a motor shaft speed by changing a power source output voltage frequency to compensate for changing slip and adjust the power source output voltage to minimize the cable current while maintaining a minimum motor voltage.

Abstract: A device determines the specific gravity of a wellbore fluid flowing into a submersible pump. The specific gravity of the wellbore fluid is determined by measuring the pressure increase across at least two pump stages and then using fluid flow properties and known pump characteristics to back calculate the specific gravity of the wellbore fluid.

Abstract: An electrical submersible pump (ESP) completion installed in casing perforated for water disposal and production. A packer separates the disposal zone and the production zone. An inverted ESP assembly is located inside of a canister. The ESP and canister are lowered on a tubing string into the casing. The canister has a downwardly extending canister extension flow-directing member that communicates with water in the casing and which passes through the disposal zone. Water is pumped down the canister extension member into the disposal zone and formation. Well fluids are drawn up the extension from the production zone. Various configurations are disclosed to facilitate flowing well fluids, e.g., oil-rich mixture or water passed the motor for cooling the motor of the inverted ESP while maintaining fluid segregation. The completion is particularly suited for production wells wherein the oil and water have a strong tendency to naturally segregate within the wellbore.

Abstract: A device determines the specific gravity of a wellbore fluid flowing into a submersible pump. The specific gravity of the wellbore fluid is determined by measuring the pressure increase across at least two pump stages and then using fluid flow properties and known pump characteristics to back calculate the specific gravity of the wellbore fluid.

Abstract: An electrical submersible pumping (ESP) system can include a pump located in a wellbore, a motor attached to the pump, a power source located at the surface, a cable electrically coupling the power source and the motor, and a current sensor. The ESP system can also include a controller communicating with the current sensor to calculate a voltage drop associated with the cable responsive to an impedance of the cable. The controller can also control a power source output voltage responsive to the calculated voltage drop. For example, the controller can adjust the power source output voltage to minimize a cable current while maintaining a minimum motor voltage. The controller can also control a motor shaft speed by changing a power source output voltage frequency to compensate for changing slip and adjust the power source output voltage to minimize the cable current while maintaining a minimum motor voltage.

Abstract: An electrical submersible pump (ESP) completion installed in casing perforated for water disposal and production. A packer separates the disposal zone and the production zone. An inverted ESP assembly is located inside of a canister. The ESP and canister are lowered on a tubing string into the casing. The canister has a downwardly extending canister extension flow-directing member that communicates with water in the casing and which passes through the disposal zone. Water is pumped down the canister extension member into the disposal zone and formation. Well fluids are drawn up the extension from the production zone. Various configurations are disclosed to facilitate flowing well fluids, e.g., oil-rich mixture or water, past the motor for cooling the motor of the inverted ESP while maintaining fluid segregation. The completion is particularly suited for production wells wherein the oil and water have a strong tendency to naturally segregate within the wellbore.

Abstract: An electrical submersible pump (ESP) completion installed in casing perforated for water disposal and production. A packer separates the disposal zone and the production zone. An inverted ESP assembly is located inside of a canister. The ESP and canister are lowered on a tubing string into the casing. The canister has a downwardly extending canister extension flow-directing member that communicates with water in the casing and which passes through the disposal zone. Water is pumped down the canister extension member into the disposal zone and formation. Well fluids are drawn up the extension from the production zone. Various configurations are disclosed to facilitate flowing well fluids, e.g., oil-rich mixture or water, past the motor for cooling the motor of the inverted ESP while maintaining fluid segregation. The completion is particularly suited for production wells wherein the oil and water have a strong tendency to naturally segregate within the wellbore.

Abstract: An electrical submersible pump (ESP) completion installed in casing perforated for water disposal and production. A packer separates the disposal zone and the production zone. An inverted ESP assembly is located inside of a canister. The ESP and canister are lowered on a tubing string into the casing. The canister has a downwardly extending canister extension flow-directing member that communicates with water in the casing and which passes through the disposal zone. Water is pumped down the canister extension member into the disposal zone and formation. Well fluids are drawn up the extension from the production zone. Various configurations are disclosed to facilitate flowing well fluids, e.g., oil-rich mixture or water passed the motor for cooling the motor of the inverted ESP while maintaining fluid segregation. The completion is particularly suited for production wells wherein the oil and water have a strong tendency to naturally segregate within the wellbore.

Abstract: A progressing cavity well pump has an overspeed brake to protect the gear box during reverse rotation. A power source rotates an input shaft of the gear box, which through a right angle drive, drives a string of rods extending into the well to the progressing cavity pump. A centrifugal brake is mounted to the input shaft. If the pump locks up, the power source will impart energy to the rods by twisting them until the power source reaches its limit. When the rods start to unwind, the centrifugal brake will engage to dissipate energy and slow the speed of the reverse rotation.