Abstract: A downhole-type tool includes a casing joint, a housing affixed to the casing joint, and an electric stator encased in the housing. The housing defines an inner bore and has an inner bore wall that is continuous with an inner wall of the casing joint. The housing is sealed against ingress of cement to the stator. The electric stator is configured to drive an electric rotor-impeller. A flow of cement can be received with an outer surface of the housing. The flow of cement can be directed into an annulus between the housing and a wall of a wellbore. The casing joint can be cemented in the wellbore.

Abstract: A device for heating oil and for reducing viscosity of the oil in an oil well is disclosed. The device comprises a pipe structure, a sucker rod, a three-way connector, a small pump cylinder, a small plunger, and a heating mechanism. The three-way connector is located below the pipe structure and has an upper end and two lower ends. The upper end of the three-way connector is connected to a bottom end of the pipe structure, and the two lower ends of the three-way connector comprises a first lower end which is coaxial with the oil pipe and a second lower end which is non-coaxial with the pipe structure. The first lower end of the three-way connector is connected to the small pump cylinder which is coaxial with the pipe structure. The second lower end of the three-way connector comprises a bypass port and a check valve. The sucker rod extends inside the pipe structure and extends through the upper end and the first lower end of the three-way connector and extends to a bottom end of the small pump cylinder.

Abstract: An electric submersible pump (ESP) is described. The ESP includes a stator chamber, a stator within the stator chamber, a rotor, and an electrical connection. The stator chamber is configured to reside in a wellbore. The stator chamber is configured to attach to a tubing of a well. The stator chamber defines an inner bore having an inner bore wall that, when the stator chamber is attached to the tubing, is continuous with an inner wall of the tubing. The rotor is positioned within the inner bore of the stator chamber. The rotor includes an impeller. The rotor is configured to be retrievable from the well while the stator remains in the well. The stator is configured to drive the rotor to rotate the impeller and induce well fluid flow in response to receiving power through the electrical connection.

Abstract: A fluid rotor and a fluid stator. The fluid stator surrounds the fluid rotor. The fluid stator has an intake end and a discharge end. The fluid stator is shaped to be inserted into a wellbore. A shaft passes through a rotational axis of the fluid rotor. The shaft is attached to the fluid rotor to rotate in union with the fluid rotor. The shaft defines a central fluid passage that extends from the intake end of the fluid rotor to the discharge end of the fluid rotor. A balance piston surrounds the shaft. The balance piston extends from an outer surface of the shaft to an inner surface of the fluid stator. The balance piston is positioned at the intake end.

Abstract: A coaxial cable connector includes a connector body having a longitudinal axis passing through first and second opposed body ends, a connector center conductor for transporting a signal through the connector, and a coil spring that is coiled about the longitudinal axis. The second body end is for engaging a male coaxial cable connector, and the coil spring urges an electromagnetic shield to protrude from the second body end.

Abstract: Methods, system and devices for deploying an MI cable heater down-hole into a hydrocarbon reservoir are provided, wherein one or more MI cables are housed inside a protective jacket, and connected to a pump-in device. The pump-in device allows the cable to be deployed by pumping fluid down-hole, and the pump-in device catches the fluid and pulls the cable down-hole, even in a horizontal well.

Abstract: To protect a hydraulic, electric and/or other conduit in an annular space around a well casing against damage from perforating and other well operations the conduit is arranged in a groove in a U- or V-shaped protective gutter, which is secured to the outer surface of the well casing and which is capable of deflecting a shaped charge.

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: Systems and methods for enhanced delivery of thermal energy to vertical wellbores are disclosed. In one embodiment, a method comprises heating a heat transfer fluid; continuously circulating the heat transfer fluid into a vertical wellbore to a downhole heat exchanger; advancing hot feedwater into the vertical wellbore to the downhole heat exchanger, wherein the downhole heat exchanger is configured to transfer heat from the heat transfer fluid to the hot feedwater to generate high-quality steam; transmitting the steam from the downhole heat exchanger into a subterranean formation, whereby thermal energy from the steam causes a reduction in viscosity of hydrocarbons in the subterranean formation; injecting an acid scale wash to counter scale buildup from the hot feedwater on the downhole heat exchanger; and returning the heat transfer fluid from the downhole heat exchanger to the surface thermal fluid heater for reheating and recirculation into the vertical wellbore.

Abstract: Method and systems relate to generating steam by transitioning water from supercritical conditions and injecting the steam that results into a formation to facilitate recovery of oil. Pressurizing and heating the water forms a supercritical fluid that may solvate impurities in the water and/or oxidize the impurities. Retaining the impurities in solution and/or oxidation of the impurities limits fouling problems associated with generating the steam from water recycled in thermal processes, such as steam assisted gravity drainage (SAGD), for recovering the oil.

Abstract: Systems and methods generate steam in hydrocarbon recovery operations and may further enable emulsion separation and product upgrading. The methods rely on indirect boiling of water by contact with a thermal transfer liquid heated to a temperature sufficient to vaporize the water. Examples of the liquid include oils, recovered hydrocarbons, liquid metals and brine. Heating of the liquid may utilize circulation of the liquid across or through a furnace, heat exchangers, or a gas-liquid contactor supplied with hot gas. Further, a solvent for bitumen introduced into the water may also vaporize upon contact with the thermal transfer liquid.

Abstract: A heat exchanger to serve ESP equipment installed on the seabed located in either a caisson or skid. A hot oil line connects the base of the ESP motor with the externally located heat exchanger, allowing hot motor oil to be circulated through coils externally exposed to seawater. The heat from the oil is rejected to the seawater and the cooled oil is reintroduced to the motor via a cold oil line that communicates with the seal section. The heat exchanger arrangement reduces the temperature of an ESP motor, thus allowing the motor to operate longer and more reliably.

Abstract: A submersible pumping system for downhole use in extracting fluids containing hydrocarbons from a well. In one embodiment, the pumping system comprises a rotary induction motor, a motor casing, one or more pump stages, and a cooling system. The rotary induction motor rotates a shaft about a longitudinal axis of rotation. The motor casing houses the rotary induction motor such that the rotary induction motor is held in fluid isolation from the fluid being extracted. The pump stages are attached to the shaft outside of the motor casing, and are configured to impart fluid being extracted from the well with an increased pressure. The cooling system is disposed at least partially within the motor casing, and transfers heat generated by operation of the rotary induction motor out of the motor casing.

Abstract: Disclosed is an installation for using geothermal energy, comprising a main pipe (20) in a borehole (10) of a well. The main pipe (20) has several through-holes (23) to the surroundings and is subdivided into a top and a bottom section by means of a transverse closure (21) that has an opening in which a device or a part of a device (22) generating and/or promoting a flow is disposed. At least one heat-utilizing device (30) is arranged within the main pipe (20) which is surrounded at least in the region of the through-holes (23), preferably everywhere, by a porous bed (11) filing at least some of the remaining hollow space of the borehole (10) around the main pipe (20). The porous bed (11) is hydraulically interrupted within the main pipe (20) by a sealing material (12) at the level of the transverse closure (21). Said installation is used for delivering or dissipating heat, decontaminating especially groundwater, and/or generating power.

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 system is provided that is capable of providing heat across a produced interval during oil and gas production to minimize or reduce undesirable formation of gas hydrates in the wellbore. In one embodiment, the configuration provides a means to recycle heat generated by an electrical submersible pump. Heat from the pump may be applied downhole. One configuration is capable of providing for downhole separation of gas from produced fluids to reduce or eliminate gas transit through the pump. A heating element also may apply heat to produced fluids. In one embodiment, a system may provide for the safe containment and control of gas within the wellbore by the utilization of a safety valve.

Abstract: An earth loop heat transfer system which, in certain aspects, has a heat transfer loop for providing heat transfer fluid to facilitate production of hydrocarbons from an earth formation; in certain aspects, to facilitate the production of sluggish crude that remains in a formation following known production methods.

Abstract: A non-rigid carrier conveys a pump and/or the steam generator through a bore of the production tubing string to support enhanced oil recovery operations. An annular space separates the production tubing string and a wall of a wellbore intersecting a hydrocarbon-bearing subterranean formation. Using the non-rigid carrier, the steam generator is conveyed into the wellbore and operated to inject hot gases into the formation through the perforations in the casing. Afterwards, the steam generator is conveyed out of the cased wellbore and the pump is conveyed into the cased wellbore and operated to pump hydrocarbons to the surface. For cyclic injection operations, the pump may be retrieved to the surface and the steam generator may be returned into the well. The production tubing string, such as a production tubing, remains in the well while the pump and/or the steam generator are conveyed up and down the cased well. A base installed in the cased well receives either the pump or the steam generator.

Abstract: A system and method is provided for heating fluid to be pumped by an electrical submersible pumping system. Heat for heating the fluid may be inductively generated by adjusting the power delivered to the motor of the pumping system. In one example, the power adjustment includes supplying the voltage applied to the pump motor to a value less than voltage applied during normal operations. While lowering the voltage the electrical frequency may be varied as well as the electrical waveform.

Abstract: The present invention provides a system and method for producing hot water without a flame. The system and method heats water to at least a specified temperature without a flame by providing a source of water and a prime mover, pumping water from the source of water into one or more heat exchangers, pre-heating the water using the one or more heat exchangers, heating the pre-heated water to at least the specified temperature without a flame using a dynamic heat generator driven by the prime mover, using the heated water in the one or more heat exchangers to pre-heat the water and providing the heated water to an output.

Abstract: A system that includes a plurality of heat sources configured to heat a portion of a formation is described. At least one production well is in the formation. A bottom portion of the production well is a sump in an underburden of the formation below the heated portion of the formation. Fluids from the heated portion of the formation are allowed to flow into the sump. A pump system has an inlet in the sump. A production conduit is coupled to the pump system. The production conduit is configured to transport fluids in the sump out of the formation.

Abstract: A method and apparatus for enhanced recovery of petroleum fluids from the subsurface by injection of a steam and hydrocarbon vaporized solvent in contact with the oil sand formation and the heavy oil and bitumen in situ. Multiple propped hydraulic fractures are constructed from the well bore into the oil sand formation and filled with a highly permeable proppant. Steam, a hydrocarbon solvent, and a non-condensing diluent gas are injected into the propped fractures, and flows upwards and outwards to contact and heat the in situ bitumen, which softens and flows by gravity to the well bore, and is pumped to the surface where the solvent can be recycled for further injection.

Abstract: A downhole arrangement including an outer housing, an inner housing disposed within the outer housing and defining with the outer housing a chamber, a turbine disposed within the chamber, and one or more nozzles disposed at the chamber capable of exhausting steam into the chamber. A method for moving a target fluid within a wellbore.

Abstract: The present invention involves a method and apparatus for enhanced recovery of petroleum fluids from the subsurface by injection of a steam and hydrocarbon vaporized solvent in contact with the oil sand formation and the heavy oil and bitumen in situ. Multiple propped hydraulic fractures are constructed from the well bore into the oil sand formation and filled with a highly permeable proppant. Steam, a hydrocarbon solvent, and a non-condensing diluent gas are injected into the well bore and the propped fractures. The injected gas flows upwards and outwards in the propped fractures contacting the oil sands and in situ bitumen on the vertical faces of the propped fractures. The steam condenses on the cool bitumen and thus heats the bitumen by conduction, while the hydrocarbon solvent vapors diffuse into the bitumen from the vertical faces of the propped fractures.

Abstract: A system and process is disclosed for retorting oil shale and extracting shale oil and other hydrocarbons therefrom, in which a cased heat delivery well is drilled generally vertically through an overburden and then through a body of oil shale to be retorted to the bottom thereof, generally horizontally under the body of oil shale to be retorted, and then back to the earth surface. Heat energy is transmitted conductively to the body of oil shale to be retorted from a closed loop heat delivery module in the well, the module comprising a fluid transmission pipe containing a heating fluid heated to at least a retorting temperature. Heat energy is also transmitted to the body of oil shale to be retorted above the fluid transmission pipe by vapor conduits that conduct retort vapors upward through the body of oil shale to be retorted; the ascending retort vapors condense and reflux, delivering their latent heat of vaporization to the body of oil shale to be retorted, and the condensed retort liquids descend.

Abstract: A mover stabilizing and stator cooling arrangement includes an upper sleeve surrounding the mover of the linear motor, a lower sleeve, a thermoconducting sleeve surrounding the stator and axially connected between the upper sleeve and the lower sleeve. The arrangement further includes a thermal grease filled in the space defined between the upper sleeve and the mover, the space defined between the thermoconducting sleeve and the stator, and the space defined between the lower sleeve and the outer tube for quick dissipation of waste heat. A stabilizer ring is set between the upper sleeve and the mover to stabilize axial movement of the mover. A piston and multiple one-way valve sets are mounted in the space between the lower sleeve and the outer tube for allowing adjustment of the volume in the thermoconducting sleeve responsive to expansion/contraction of the thermal grease due to temperature changes.

Abstract: A system for treating a subsurface hydrocarbon containing formation includes one or more shafts. A first substantially horizontal or inclined tunnel extends from one or more of the shafts. A second substantially horizontal or inclined tunnel extends from one or more of the shafts. Two or more heat source wellbores extend from the first tunnel to the second tunnel. The heat source wellbores are configured to allow heated fluid to flow through the wellbores from the first tunnel to the second tunnel.

Abstract: A submersible pumping system for use downhole that includes a housing containing an expandable fluid, that when expanded pushes a piston that in turn pumps wellbore fluid to the surface. The expandable fluid can be a silicon based heat transfer fluid with a coefficient of thermal expansion of at least about 0.0005 in3/in3/° F. The expandable fluid is expanded upon exposure to heat. A heat source is selectively activated for expanding the fluid.

Abstract: Presented is a system for extracting subsurface oil using microwave or RF energy generated above the ground surface, and directed to an underground oil bearing location using a coaxial transmission line functioning as a wave guide.

Abstract: The present invention features ground water heat transfer systems utilizing polypipes. A typical system of the invention comprises (1) a water pump which is suspended or affixed in a deep well and connected to at least one inlet polypipe, where the inlet polypipe(s) is extended to the bottom of the well and comprises a bottom portion including one or more openings; (2) a heat exchange system connected to the water pump; and (3) a return pipe connected to the heat transfer system and having an outlet extending below the water level in the well. The opening(s) at or near the bottom of the inlet polypipe(s) allow water to enter the polypipe(s) and be pumped to the heat exchange system. After heat exchange, the water can be returned to the same well or different well(s) through the return pipe(s). In many cases, the systems of the invention are open-loop systems.

Abstract: A system and method is provided for heating fluid to be pumped by an electrical submersible pumping system. Heat for heating the fluid may be inductively generated by adjusting the power delivered to the motor of the pumping system. In one example, the power adjustment includes supplying the voltage applied to the pump motor to a value less than voltage applied during normal operations. While lowering the voltage the electrical frequency may be varied as well as the electrical waveform.

Abstract: The present invention involves a method and apparatus for enhanced recovery of petroleum fluids from the subsurface by injection of a steam and hydrocarbon vaporized solvent in contact with the oil sand formation and the heavy oil and bitumen in situ. Multiple propped hydraulic fractures are constructed from the well bore into the oil sand formation and filled with a highly permeable proppant. Steam, a hydrocarbon solvent, and a non-condensing diluent gas are injected into the well bore and the propped fractures. The injected gas flows upwards and outwards in the propped fractures contacting the oil sands and in situ bitumen on the vertical faces of the propped fractures. The steam condenses on the cool bitumen and thus heats the bitumen by conduction, while the hydrocarbon solvent vapors diffuse into the bitumen from the vertical faces of the propped fractures.

Abstract: Methods and systems and are described for isolating or manipulating a sample of a heavy oil composition from a hydrocarbon reservoir. One method embodiment of the invention comprises circulating a heated fluid in a first region of a reservoir where a heavy oil composition is present or believed present using a surface pump and a well completion comprising a downhole pump for a time and flow rate sufficient to produce flowable heavy oil composition, the well completion comprising a sampling tool; and sampling the flowable heavy oil composition using the sampling tool. This abstract complies with rules requiring an abstract. It should not be used to limit the scope or meaning of the claims. 37 CFR 1.72(b).

Abstract: A down hole heating system for use with oil and gas wells which exhibit less than optimally achievable flow rates because of high oil viscosity and/or blockage by paraffin (or similar meltable petroleum byproducts). The heating unit the present invention includes shielding to prevent physical damage and shortages to electrical connections within the heating unit while down hole (a previously unrecognized source of system failures in prior art systems). The over-all heating system also includes heat retaining components to focus and contain heat in the production zone to promote flow to, and not just within, the production tubing.

Abstract: Certain embodiments provide a method for treating a subsurface formation. The method includes using heaters to form a heated portion of the subsurface formation. A production conduit is used to direct formation fluid in a vapor phase from the heated portion of the subsurface formation towards a surface of the subsurface formation. Condensate of the vapor phase formation fluid is formed in or near the production conduit. Condensate of the vapor phase formation fluid is diverted to a desired location.

Abstract: The production rate, useful life and operating efficiency of electric submergible pumping systems (ESP) is improved by operating the system so that the motor (220, 320) is cooled by two passes of production. Production fluids remove waste heat from the motor (220, 320) by passing the fluid in contact with the exterior of the motor (220, 320). The improved cooling permits the motor to be operated at a lower temperature improving life and efficiency, and/or to be operated at higher power at a similar temperature. Additionally, oversized and excess equipment is not required, further improving performance and economics for the user. In another aspect, the invention is a method of pumping fluids using a motor having vortex generators (366) on its exterior surfaces or on the interior surfaces of a surrounding shroud.

Abstract: A device for determining a location of an interface between a first fluid and second fluid includes a non-mechanical sensor that measures a selected parameter of interest relating to the fluid surrounding the sensor (“the surrounding fluid”) and a processor for processing the sensor measurements. The non-mechanical sensor measures a parameter relating to the surround fluid without physically co-acting with the surrounding fluid. Exemplary parameters such as thermal properties, electrical properties, fluid properties, and magnetic properties can be measured. The processor is programmed to process the sensor measurements to identify one or more characteristics in the measurements that can indicate the nature of the fluid being measured and thereby determine the location of the interface. The determined location can be used to operate a downhole device such as a pump, to provide real-time monitoring of well conditions, to record data for long-term reservoir characterization, or to actuate an alarm.

Abstract: An apparatus for warming objects such as production conduits at a well site comprises an internal combustion engine driving a well pump. A heat exchanger shell is connected to an exhaust port of the engine, and has an output port. A circulating pump is driven by the engine, and a heating circuit is connected to the circulating pump such that liquid in the heating circuit is pumped from a pump output of the circulating pump through the heating circuit to a pump intake of the circulating pump. The heating circuit comprises a heat absorbing portion inside the heat exchanger shell arranged such that heat from the exhaust of the engine is transferred to the liquid therein, and a heating conduit arranged adjacent to a production conduit or other desired object such that heat from the liquid in the heating conduit is transferred to the object.

Abstract: The present invention is directed to an apparatus and a method for cleaning the open perforations in a well and for bailing a well. The apparatus has a tubular conduit with at least one seal attached to it that forms a seal between the well casing and the exterior of the conduit. The seal is held in place on the tubular conduit by two shoulders formed where the upper and lower sections of the conduit meet a middle section. The upper end of the conduit is adapted to releasably engage the lower end of a bailer. The upper end of the conduit releasably engages the middle section and can be removed to replace the seals when worn. The apparatus has a valve section designed to releasably engage the lower end of the tubular conduit or the lower end of a bailer.

Abstract: A method and system for downhole treatment and pumping of well fluids enhances the pumping of viscous fluids to the surface. The first step is to separate the oil and water from the well fluid and then channel the oil to a chamber that encloses the motor. The heat from the motor will increase the heat of the crude oil flowing past the motor, thereby lowering the viscosity of the crude oil. The water flows separately past the motor in another passageway, and remixes with the oil. After the oil and water recombine, the treated well fluid has a lower viscosity, and the fluid is then pumped to the surface more efficiently than without treating the oil.

Abstract: The present invention provides a electric submersible pump assembly for producing a fluid from a production zone to the surface and operated independently by one or more electric submersible motors using a dual or multiple gearbox, the electric submersible pump assembly including an inlet pump having a section head into which fluid enters from the production zone to the inlet pump, an outlet pump having an intake section communicating with the inlet pump so that fluid received therefrom is discharged through the outlet pump, an electric submersible motor, a first motor interface that connects the electric submersible motor to the inlet pump, and a second motor interface that connects the electric submersible motor to the outlet pump; each motor interface having a gearbox that connects to the electric submersible motor, a pump shaft connector that connects to the pump, and a seal section that joins the pump shaft connector to the gearbox.

Abstract: A viscosity handling system for facilitating the movement of certain fluids. The system utilizes kinetic energy in the form of a rapidly and repetitively moving component that imparts energy in the form of heat to surrounding fluid. The system is particularly useful in applications, such as downhole pumping systems, used to produce hydrocarbon-based fluids from beneath the surface of the earth.

Abstract: An apparatus for reducing paraffin and asphaltene deposits in a pumping oil well including a polish rod having a portion extending outwardly of the earth and having a portion extending into an oil string tubing, a sucker rod string interconnected to the polish rod and extending through the oil string casing into the earth, and an insulating rod interconnected to a lower end of the polish rod and interconnected to an upper end of the sucker rod string. The insulating rod is formed of a material having a thermal conductivity of 0.0167 to 0.06 BTU/(sq.ft.)(hr)(deg.F)(ft). The insulating rod is formed of a body of fiberglass material, an upper connector affixed to the body and formed of a steel material, and a lower connector affixed to the body and formed of a steel material.

Abstract: The production rate, useful life and operating efficiency of electric submergible pumping systems (ESP) is improved by operating the system so that the motor is cooled by two passes of production. The two passes of production fluid are achieved by employing a shroud with the inlet at the opposite end of the production fluid intake or by installing the motor below the perforations that allow production fluids to enter a well. The motor is designed with an internal conduit through which the production fluids are pumped. Production fluids remove waste heat from the motor by passing in fluid contact with the exterior of the motor and again by passing through the internal conduit of the motor. The improved cooling permits the motor to be operated at a lower temperature improving life and efficiency, and/or to be operated at higher power at a similar temperature. Additionally, oversized and excess equipment is not required, further improving performance and economics for the user.

Abstract: A method and apparatus for unplugging a well or pipe obstructed by a gas hydrates. According to the invention, a moving heating element is applied against one end of the hydrate plug, and is displaced axially in the tube or the pipe towards the other end, so as to cause the plug to melt progressively from one end to the other. Application to the oil industry, in particular in off-shore wells.

Abstract: A system for pumping and heating viscous fluids in a wellbore includes electrical power supplies, a switchboard, conductors, and a submergible pumping system having a pump and a submergible electric motor. The electrical power supplies are coupled to the submergible pumping system through a switchboard and conductors that supply electrical power to the motor. The electrical power supplies provide direct or alternating current and include protective circuitry. The submergible pumping system may be supplied with electrical power to motor stator windings to generate heat to raise the temperature and lower the viscosity of adjacent viscous fluids.

Abstract: A system allows the pumping of viscous fluids from a wellbore. The system includes a submergible pump and a pump intake through which a fluid may be drawn. A submergible electric motor powers the submergible pump, and a heater is connected in the pumping system to heat the wellbore fluid. Additionally, a combination of heaters may be employed to heat the desired production fluid both externally to the pumping system and internally to the pumping system.

Abstract: A sensor assembly is used with a submergible pumping system within a wellbore. The sensor assembly is an integral part of the string of submergible components that form the submergible pumping system. One embodiment of the sensor assembly utilizes a sensor for detecting the axial downthrust load acting on the shaft of a submergible pump. The downthrust load can be used to determine, for instance, flow rate through the submergible pump.

Abstract: extending into a hot subterranean hydrocarbon-bearing formation containing water at greater than 100.degree. C. The wellbore is divided into three co-extensive passageways; an annulus, and first and second conduits. The annulus is formed within the wellbore between a block at its bottom above the completion intervals and an outlet at the wellhead. The first conduit extends from the formation, through the bottom of the annulus and to an outlet at an elevation intermediate up the annulus. The first conduit is insulated between the bottom of the annulus and its outlet. A second conduit extends between the bottom of the annulus and an outlet at the wellhead. In operation, by producing fluid from the annulus and the second conduit outlets at the wellhead, formation fluid is induced to rise up the first conduit. While the fluid rises, contained water flashes providing steam-enhanced lift.

Abstract: A system for heating viscous fluids in a wellbore includes a submergible pumping system comprising a pump and submergible electric motor. A heating unit is coupled to the pumping system and is supplied with electrical energy through a cable used to supply electrical energy to the motor. The heating unit may include a direct or alternating current heater and protective circuitry. The heating unit may be supplied with electrical energy through the motor stator windings or via a jumper arranged in parallel with the stator windings. Switches may be included in the heating unit and in a motor base for energizing the motor and the heating unit based upon sensed temperatures of the viscous fluids surrounding the pumping system.