Abstract: An electrical submersible pump assembly has pump, motor and pressure equalizer modules. A first adapter, which secures to the first module, has an external set of first adapter threads. A second adapter, which secures to the second module, has an external set of second adapter threads. A collar has an internal set of collar first threads that engage the first adapter threads, and an internal set of collar second threads that engage the second adapter threads. The collar first and second threads differ from each other, such that rotation of the collar relative to the first and second modules pulls the first and second modules toward each other. The pitches of the collar first and second threads may differ. Or, the collar first and second threads may turn in opposite directions.

Abstract: A centrifugal well fluid pump has a pump intake and a pump discharge conduit extending upward from the pump. A barrier between the motor and the pump intake seals to casing in a well. A bypass tube extends from below the barrier, alongside the pump and has an outlet at an upper end of the pump. A riser surrounds the pump discharge conduit, the riser having a riser inlet in fluid communication with the bypass tube outlet. Liquid portions of the well fluid flow upward through the riser to discharge from the riser outlet and flow down to the pump intake. Gaseous portions of the well fluid flow upward through the riser and continue flowing upward into the casing.

Abstract: A well pump assembly has a barrel, a standing valve at an upper end of a standing valve chamber, and a plunger. A travelling valve admits well fluid into the barrel during a fill stroke. The travelling valve closes during a power stroke so that the plunger pushes well fluid from the barrel into the standing valve chamber. A gas release port extends from the standing valve chamber to the exterior of the pump assembly. A check valve in the gas release port has an outward flow blocking position for blocking liquid well fluid in the standing valve chamber from exiting through the gas release port while the plunger is in the power stroke. The check valve has a gas release position that enables gas present in the standing valve chamber to flow out the gas release port while the plunger is in the power stroke.

Abstract: An electrical submersible pump (ESP) having a sleeve coupled to the shaft that rotates as the shaft rotates. The sleeve can be a base portion of a pump impeller, a journal bearing, or a bushing. A drive collar mounts around the shaft and has an end with a portion that projects past an end of the sleeve profiled to correspond with the shape of the projecting portion. As the shaft rotates the drive collar the projecting portion of the drive collar pushes against the profiled end of the sleeve to rotate the sleeve. The projecting portion can be a wedge shaped tab on the drive collar, or an angular segment of the drive collar extending axially past the remaining segments. The profiled end of the sleeve can include a recess formed to receive the tab and can have an angular segment corresponding to that on the drive collar.

Abstract: A centrifugal well fluid pump has a pump intake and a pump discharge conduit extending upward from the pump. A barrier between the motor and the pump intake seals to casing in a well. A bypass tube extends from below the barrier, alongside the pump and has an outlet at an upper end of the pump. A riser surrounds the pump discharge conduit, the riser having a riser inlet in fluid communication with the bypass tube outlet. Liquid portions of the well fluid flow upward through the riser to discharge from the riser outlet and flow down to the pump intake. Gaseous portions of the well fluid flow upward through the riser and continue flowing upward into the casing.

Abstract: An electrical submersible pump assembly has pump, motor and pressure equalizer modules. A first adapter, which secures to the first module, has an external set of first adapter threads. A second adapter, which secures to the second module, has an external set of second adapter threads. A collar has an internal set of collar first threads that engage the first adapter threads, and an internal set of collar second threads that engage the second adapter threads. The collar first and second threads differ from each other, such that rotation of the collar relative to the first and second modules pulls the first and second modules toward each other. The pitches of the collar first and second threads may differ. Or, the collar first and second threads may turn in opposite directions.

Abstract: A downhole well pumping assembly has a shroud with an upper section and a lower section sealed from one another. A submersible pump and a gas separator are housed within the upper section of the shroud. The gas separator has a liquid outlet in fluid communication with an intake of the pump, and a gas outlet in fluid communication with the gas outlet in the shroud. A motor is housed within the lower section of the shroud, the motor being coupled to the gas separator for rotating the gas separator and the pump. A well fluid lower inlet is in the shroud below the motor and a well fluid lower outlet is in the shroud above the motor.

Abstract: An electric submersible pump (ESP) torque absorbtion anchor system (TAS) and a method to assemble the same are disclosed. The TAS includes a collar having an uphole end coupled to a production string and a flange formed on an outer diameter of the collar. The TAS also includes a sleeve having a rim extending radially inward from an uphole end of the sleeve. The collar is positioned in a cavity of the sleeve so that oppositely facing shoulders of the collar and the sleeve contact and transfer axial loads between the sleeve and the collar. A spring is positioned in an annulus between the sleeve and the collar and mounts to the collar and the sleeve so that rotational loading of the sleeve relative to the collar transfers to the spring.

Abstract: A submersible pumping system, electrical submersible pump, and method of providing enhanced alignment of motor and driven shafts of submersible pumping systems and electrical submersible pumps, are provided. An example of an electrical submersible pump system includes a pump, a pump motor, and a seal section. The motor drives the pump via motor and driven shafts rotatingly coupled with a coupling assembly. The coupling assembly maintains the shaft ends in coaxial alignment with an alignment device. The alignment device is profiled on opposite ends for mating engagement with the centering guides extending from the shaft ends.

Abstract: A method to separate a gas phase from a liquid phase in a subterranean formation that includes positioning a downhole tool in a wellbore, operating the downhole tool to form perforations in the subterranean formation in a manner that creates cyclonic motion in fluids that exit the subterranean formation and enter the wellbore through the perforations, the fluid having a gas phase and a liquid phase, and producing the liquid phase to the surface, whereby the liquid phase is substantially devoid of the gas phase as a result of the cyclonic motion.

Abstract: Devices and methods for detecting operational parameters associated with a gas separator used in an electric submersible pump in a wellbore. A fiber optic sensing arrangement is used to detect the operational parameter and includes a fiber optic signal processor and an optic fiber that is associated with the gas separator to provide a signal indicative of the parameter to the signal processor.

Abstract: Vibration of an electric submersible pump assembly is monitored to produce a vibration spectrum. The vibration spectrum is compared to a known vibration signature for a pump condition that precedes gas lock. The pump condition is at least one of an impeller rotating stall condition, a diffuser stall condition, a pre-surge condition, and percentage of free gas within the wellbore fluid. Operation of the pump is then adjusted in response to the similarity of the vibration spectrum to the vibration signature for the pump condition to prevent impending gas lock.

Abstract: A gas separator having an improved flowpath for lighter fluids having a higher concentration of gas decreases total pumping head for an ESP assembly. The ESP assembly includes a rotary primary pump, a motor coupled to the primary pump for driving the pump, a seal assembly between the primary pump and the motor, and a gas separator between the seal assembly and the primary pump. An outlet of the gas separator feeds an intake of the primary pump, and a rotating shaft operationally couples the primary pump to the motor and passes through the seal assembly and the gas separator. The gas separator contains a venting portion, and a diverter positioned within the venting portion having diverter guide vanes formed in a flowpath of the lighter fluid for aiding in a directional change of fluid momentum. A slinger is positioned within the diverter for impelling fluid through the venting port.

Abstract: Systems and methods of cooling a motor of an electrical submersible pump (ESP) assembly employed in an electrical submersible subsea booster pumping system, are provided. A supporting frame structure such as an ESP mounting skid or top end assembly of a caisson having structural members exposed to environmental seawater, is modified or designed to include fluid conduits within the structural members to establish lubricant pathways for lubricant to flow. A heated/hot lubricant line connects between a supporting structure lubricant inlet port and an ESP motor lubricant outlet port. A cooled lubricant line connects between a supporting structure lubricant outlet port and an ESP motor lubricant inlet port. A pump or other fluid moving device circulates lubricant from the ESP motor to the lubricant pathways within the supporting frame structure, whereby the seawater cools the lubricant contained therein, which is then circulated back into the motor to assisting cooling the motor.

Abstract: Devices and methods for detecting operational parameters associated with a gas separator used in an electric submersible pump in a wellbore. A fiber optic sensing arrangement is used to detect the operational parameter and includes a fiber optic signal processor and an optic fiber that is associated with the gas separator to provide a signal indicative of the parameter to the signal processor.

Abstract: A submersible pumping system, electrical submersible pump, and method of providing enhanced alignment of motor and driven shafts of submersible pumping systems and electrical submersible pumps, are provided. An example of an electrical submersible pump system includes a pump, a pump motor, and a seal section. The motor drives the pump via motor and driven shafts rotatingly coupled with a coupling assembly. The coupling assembly maintains the shaft ends in coaxial alignment with an alignment device. The alignment device is profiled on opposite ends for mating engagement with the centering guides extending from the shaft ends.

Abstract: A submersible pumping system, electrical submersible pump, and method of providing enhanced alignment of motor and driven shafts of submersible pumping systems and electrical submersible pumps, are provided. An example of an electrical submersible pump system includes a pump, a pump motor, and a seal section. The motor drives the pump via motor and driven shafts rotatingly coupled with a coupling assembly. The coupling assembly maintains the shaft ends in coaxial alignment with an alignment device. The alignment device is profiled on opposite ends for mating engagement with the centering profiles extending into the shaft ends.

Abstract: A connection between a shaft and a coupling that preferably involves involute shaped splines is designed to reduce stress from torque applied to the shaft by a drive motor. To avoid stress concentration at the mouth of the coupling on startup, the shaft splines are made to taper from the shaft end down to the spline end. As a result, the initial contact with the coupling splines occurs within the coupling and removed from it mouth. The shaft is allowed to elastically twist in response to the applied torque as the contact area increases with shaft twisting and the contact line moves toward the mouth of the coupling. Some shaft elastic twist occurs without adding stress to the shaft splines until coupling contact is made.

Abstract: A downhole well pumping assembly has a shroud with an upper section and a lower section sealed from one another. A submersible pump and a gas separator are housed within the upper section of the shroud. The gas separator has a liquid outlet in fluid communication with an intake of the pump, and a gas outlet in fluid communication with the gas outlet in the shroud. A motor is housed within the lower section of the shroud, the motor being coupled to the gas separator for rotating the gas Separator and the pump. A well fluid lower inlet is in the shroud below the motor and a well fluid lower outlet is in the shroud above the motor.

Abstract: A seafloor pump assembly is installed within a caisson that has an upper end for receiving a flow of fluid containing gas and liquid. The pump assembly is enclosed within a shroud that has an upper end that seals around the pump assembly and a lower end that is below the motor and is open. A separating device is connected to an upper end portion of the discharge pipe within the caisson. The separating device causes separation of gas from the flow containing gas and liquid to be enhanced prior to the flow reaching the operating liquid level in the caisson.