Submersible pumps

Information

  • Patent Grant
  • 6557642
  • Patent Number
    6,557,642
  • Date Filed
    Wednesday, February 28, 2001
    23 years ago
  • Date Issued
    Tuesday, May 6, 2003
    21 years ago
Abstract
An oil flow line and power device system has a tube for the transportation of oil and a power device which can be received in the tube. The tube is provided with an electric power transmission line extending along at least some of the length and has a first power transfer unit which can cooperate with a second power transfer unit on the power outlet device such that the other power transfer units cooperate to transfer power from the transmission line to the power device.
Description




FIELD OF THE INVENTION




This invention relates to submersible pumps and the like, in particular the deployment and retrieval of semi-permanent assemblies into wells and pipelines, especially electrically powered assemblies such as electric submersible pumps (ESPs) and flow regulators based on permanent magnet brushless motors.




BACKGROUND OF THE INVENTION




A conventional electrical submersible pump installation for oil wells is deployed at the end of a production tubing, the tubing being used to conduct the pumped fluids to surface. The tubing consists of jointed sections, to which the electrical power cable is externally strapped. The motor and centrifugal or positive displacement pump are assembled at the bottom of the tubing, normally with the pump above the motor, so it can lift fluids via a discharge head directly into the tubing.




The ESP must be maintained from time to time. This requires a so-called work-over rig and crew which can pull up and dismantle the sections of tubing from the well and detach the cable to retrieve the pump. The repaired or replaced pump is deployed back into the well as for a new installation, re-making the tubing and affixing the cable. Since there is a high likelihood of damaging the cable and its connectors, these are often replaced during the work-over. This type of work-over is a time consuming and expensive exercise, and it is often done to a fixed schedule that leaves failed installations until the next scheduled slot, with consequent lengthy periods without production.




An alternative known method of ESP installation disclosed in GB 2 318 167 uses coiled tubing. In this the power cable is pre-installed into the continuous tubing and makes on to the motor, which is now above the pump. The fluids are lifted in the annulus between the tubing and the well casing. Since the ESP is reeled into and out of the well, work-over costs are significantly reduced compared to the conventional means of installation. Nevertheless the method requires the use of a reeled tubing rig and remains expensive.




It is an objective of this invention to allow convenient recovery of components disposed in a well or pipeline.




SUMMARY OF THE INVENTION




According to the present invention, there is provided an oil flow line and powered device system comprising:




a tube for the transportation of oil, and




at least one powered device, the powered device being disposable in the tube,




the tube having an electrical power transmission means disposed along at least some of its length,




the tube having a first power transfer means, and the powered device having a second power transfer means, the first power transfer means and second transfer means being capable of co-operating so as to transfer power from one to the other.




Preferably the first power transfer means act as a stator of a motor, and the second power transfer means act as a rotor of a motor.




Preferably the inner surface of the tube includes at least one locating means for locating the powered device at a particular position in the tube




Alternatively or additionally the powered device includes a gripping means to secure itself to the inner surface of a tube.




According to another aspect of the present invention, there is provided a method of delivering or retrieving a powered device in a powered device and flow line system oil flow line and powered device system comprising:




a tube for the transportation of oil, and




at least one powered device, the powered device being disposable in the tube,




the tube having an electrical power transmission means disposed along at least some of its length,




the tube having a first power transfer means, and the powered device having a second power transfer means, the first power transfer means and second transfer means being capable of co-operating so as to transfer power from one to the other,




including the step of applying fluid pressure to the flow line.




According to another aspect of the present invention, there is provided a method of delivering or retrieving a powered device in a powered device and flow line system comprising:




a tube for the transportation of oil, and




at least one powered device, the powered device being disposable in the tube,




the tube having an electrical power transmission means disposed along at least some of its length,




the tube having a first power transfer means, and the powered device having a second power transfer means, the first power transfer means and second transfer means being capable of co-operating so as to transfer power from one to the other,




including the step of operating a traction means to interact between the tube and the powered device.




According to a further aspect of the present invention, there is provided a tube for an oil flow line and powered device system the oil flow line and powered device system comprising:




a tube for the transportation of oil, and




at least one powered device, the powered device being disposable in the tube, the tube having an electrical power transmission means disposed along at least some of its length,




the tube having a first power transfer means, and the powered device having a second power transfer means, the first power transfer means and second transfer means being capable of co-operating so as to transfer power from one to the other.




According to a further aspect of the present invention, there is provided a powered device for an oil flow line and powered device system the oil flow line and powered device system comprising:




a tube for the transportation of oil, and




at least one powered device, the powered device being disposable in the tube,




the tube having an electrical power transmission means disposed along at least some of its length,




the tube having a first power transfer means, and the powered device having a second power transfer means, the first power transfer means and second transfer means being capable of co-operating so as to transfer power from one to the other.




The powered device may include a traction means which interacts between the tube and the powered device so as move the powered device along the flow line.




It is a further objective of this invention that said docking ports be addressable when required to permit individual control.




In this way, the electrical power cable, its connectors, and production tubing remains in the well during an entire ESP work-over. Docking ports are used to station and operate modular pumps, valves, sensors and/or other actuators at one or more locations, said docking ports possibly being addressable when required to permit individual control.




The modules may be recovered by the production fluids themselves as an alternative or in addition to special hydraulic fluids. These modules are recovered by re-circulating the said fluids using a permanent flow path in or attached to the production tubing. The modules are also recoverable by a wireline or slickline operation for back-up or primary means of recovery, and by electric powered traction tools.




Electrical connections between said modules and docking ports are not required. Rotary or linear motor action be developed using stator coils mounted in or on the fixed part of the downhole assembly and permanent magnets mounted in or on the said modules. The said modules may be individually controlled from the same power supply.











BRIEF DESCRIPTION OF THE DRAWINGS




The invention will now be described with refernce to the accompanying drawings, given as examples and not intended to be limiting, in which:,





FIG. 1

shows a side view of a well with an ESP installed using coiled tubing deployment;





FIG. 2

shows a side view of a well with an ESP installed using conventional jointed tubing and externally strapped power cable deployment;





FIG. 3

shows a side view of a well with jointed tubing and externally strapped power cable connected to full bore docking ports incorporating electrical power coils;





FIG. 4

shows a side view of a well with coiled tubing with internal power cable (not shown) connected to full bore docking ports incorporating electrical power coils;





FIG. 4



a


shows a 3 dimensional perspective of twin-wall coiled tubing used in

FIG. 4

, forming a conduit for internal power and other cables;





FIG. 5

shows a side view of another embodiment of a well with jointed tubing and externally strapped power cable connected to full bore docking ports incorporating electrical power coils;





FIG. 6

shows a side view of another embodiment of a well with coiled tubing with internal power cable (not shown) connected to full bore docking ports incorporating electrical power coils;





FIG. 6



a


shows a 3 dimensional perspective of twin-wall coiled tubing used in

FIG. 6

, showing the tubing's inductor arrangement;





FIG. 7

shows a side view of a more detailed view of

FIG. 4

of the lower section of the well with pump modules located in their docking stations and a pump out seal positioned, not in operation, at the lower most end of the tubing;





FIG. 8

shows a similar view to

FIG. 7

with the pump out seal activated and moving up the tubing:





FIG. 9

shows a similar view to

FIG. 7

with the pump out seal conveying one pump module out of the well and preparing to collect a second pump;





FIG. 10

shows another embodiment in a sectional view;





FIGS. 11

to


13


show another embodiment of the operation of the pumping modules within the tubing;





FIGS. 14

to


19


show side views of a further embodiments of the pumping module;





FIG. 20

shows a side view of a docked electrically actuated flow control module;





FIG. 21

shows another embodiment of an electrically actuated flow control module;





FIGS. 22

to


24


show side views and a section of a docked sensor module, with charging and signal transfer;





FIGS. 25

to


27


show side views of another embodiment of operating the system.





FIG. 28

shows a side view of a floating production vessel in the ocean with a flow line linking it to subsea wellheads, said flow line containing docking ports;





FIG. 29

is a schematic view of the wiring arrangement of a docking station; and





FIG. 30

shows another embodiment of the system shown in FIG.


28


;











DESCRIPTION OF THE PREFERRED EMBODIMENT




Referring to

FIGS. 1 and 2

, these show the existing state of the art.

FIG. 1

shows a coiled tubing deployed ESP. Well casing


1


provides a passage from the reservoir to the surface. A sealing device


2


, generally referred to as a packer, separates the pump inlet


3


from pump discharge port


4


. The ESP is supported by coiled tubing


5


which has a power cable


6


installed inside its bore, terminating directly into the electrical motor


7


. The electric motor output shaft connects to the pump input shaft near


8


, around which is the pump discharge port


4


.





FIG. 2

shows the jointed tubing conveyed version of the electrical submersible pump. In this embodiment the jointed tubing


9


has an externally strapped power cable


10


. The power cable is fed through the packer


2


by a penetrator (or electrical bulkhead)


11


, the cable being terminated at either end of the penetrator by electrical cable terminations


12


. The cable passes down the side of the pump section


13


and attaches to the electrical motor


14


via an electrical pot head connector


15


.




It is clear from both of these embodiments that once any part of the ESP has failed the entire assembly has to be removed to be repaired or replaced. The most likely failures are of rotary seals, bearings and pump stages, which are moving parts unlike the cable, its connectors, and the motor windings. Referring to

FIGS. 3

,


4


and


4




a,


there are shown two embodiments of the present invention's well infrastructure.

FIG. 3

shows jointed tubing, with an externally strapped power cable


10


terminated at one or more docking ports


20


, and actuator fluid conduit


19


. The docking ports contain electrical coils


21


and location profile


22


. These items are permanently installed and not disturbed during workover operations. The coils may be permanently sealed in an insulating environment, such as oil, polyamide varnish, epoxy or elastomer filling.




A similar system where the jointed tube has no location profile is shown in FIG.


5


. In such a system, it is necessary for the ESP to actively grip and support itself in the jointed tube's bore, as will be described in more detail below.





FIG. 4

shows a similar view to FIG.


3


. In this embodiment the power cables are integral with the coiled tubing


23


and have not been shown for clarity.

FIG. 4



a


shows two concentric coiled tubing skins


26


,


27


. The annular space thereby formed houses the integral power wiring


28


and other well support infrastructure such as fiber optics


28


′ and hydraulic control lines


28


″.




Free space in the annulus may be used as a means of passing actuator fluid in place of a special line or the externally strapped flow tube


19


shown in FIG.


3


. An embodiment where the coiled tubing has no engaging profile is shown in FIG.


6


. Where no engaging profile is present, the ESP must actively grip the inner surface of the coiled tube to secure its position. Referring to

FIG. 6



a


, the inductor elements are arranged radially in the thickness of the coiled tubing.




In all these embodiments there is full bore access


25


to the reservoir when no pumping modules are installed. This is beneficial for well operations which require the passage of, for example, higher flows, drilling and de-scaling equipment, and large modules. It will be apparent that these permanently wired docking stations can be used with other modules and are not restricted to pumping. A plurality of docking stations can be installed, with a mix of modules performing different functions simultaneously.




Retrieval and deployment of modules according to the invention will be explained with reference to

FIGS. 7

,


8


and


9


. By way of example, these show two pumping modules installed in the coiled tubing completion of

FIG. 4

, but it will be apparent that the method to be explained will work in the jointed pipe completion of FIG.


3


and with any mix of module types. It will also be apparent that the non-return valves


30


and


35


may be of different types known in the art.





FIG. 7

shows upper


100


′ and lower


100


pump modules docked. They are held in position by integral collets


103


and location profiles


22


. At the lower-most end of the tubing is a spring-loaded non-return valve


30


, and a mechanical docking port


31


for a pump out seal


32


. The seal fits over a hollow spigot


101


that is part of the docking port. The resultant small trapped volume between


31


and


32


is connected via an inlet to the aforementioned flow line


19


or


29


. The seal carries a spring-loaded non-return valve


35


which is held open by the spigot


101


when in the docked position.




In normal operation flow in the well holds valve


30


open. To recover the pump modules, electrical power is first preferably turned off. Control fluid is pumped down the flow path inside the coiled tubing


29


and pressurizes the trapped volume


31


′, forcing the seal


32


to rise. When the seal eventually rises off the spigot


101


, the valve


35


springs closed and blocks production flow. This equalizes pressure across valve


30


, so that it springs shut, leaving a trapped volume


33


between the two valves


30


and


35


. This volume is a large extension of the original volume


31


′, so that continued control fluid flow will now continue to move the seal up the tubing bore. When it reaches the lower pumping module


100


it removes the hanging weight from location collets


103


, which unlatches them from their location profiles


22


in the tubing. By continuing to pump fluid down flow path


29


the pump module


100


is displaced to the upper pump module


100


′. Continued displacement unlatches this second module, and thence both back to surface. After a short period of time determined by the flow rate in


29


the modules are all recovered back to surface where they can be either repaired or replaced.




To reinstall the pump modules the reverse operation is performed. A new pump out seal is first installed. This allows the lowering of all the pump out modules at a controlled descent rate. It will be appreciated that if a lower pumping module is still operating correctly, this could be used to pump out the pump modules above it.




If pumping out is not preferred, or the pump out seal fails, a wire-line or slick-line could be lowered which would connect to a fishing profile


104


on top of each module to allow their recovery one by one. Alternatively, particularly in horizontal sections, the modules could be deployed and retrieved using autonomous or wireline powered tractors.




The mechanical latch


22


/


103


may be varied according to particular requirements. For example, it may need spines to prevent rotation, as when supporting torque reaction from a pump. The details of such embodiments are covered by the present invention which discloses the principle of the docking port.





FIGS. 10

,


11


and


12


show a similar system adapted for a jointed tubing system, the jointed tubing having no engaging profile and the pump anchoring and sealing itself against the inner surface of the tubing with slips


103


and seal


103


′ at the power transfer port


20


. As before, at the lower-most end of the tubing is a spring-loaded non-return valve


30


, and a mechanical docking port


31


for a pump out seal


32


. The seal fits over a hollow spigot


101


that is part of the docking port. The resultant small trapped volume


31


′, between


31


and


32


is connected via an inlet


31


″ to the aforementioned flow line


19


or


29


. The seal carries a spring-loaded non-return valve


35


which is held open by the spigot


101


when in the docked position.




The normal operation is similar to the previous system. The flow in the well holds valve


30


open. To recover the pump modules, electrical power is first preferably turned off. Control fluid is pumped down the flow path inside the coiled tubing


29


and pressurizes the trapped volume


31


′, forcing the seal


32


to rise, as shown in FIG.


11


. When the seal eventually rises off the spigot


101


, the valve


35


springs closed and blocks production flow. This equalizes pressure across valve


30


, so that it springs shut, leaving a trapped volume


33


between the two valves


30


and


35


. This volume is a large extension of the original volume


31


′, so that continued control fluid flow will now continue to move the seal up the tubing bore. When it reaches the lower pumping module


100


it removes the hanging weight from slips


103


and seal


103


′, which disconnects the pump module


100


from the inner surface of the tubing. By continuing to pump fluid down flow path


29


the pump module


100


is displaced up tubing. Continued displacement unlatches this second module (not shown), and thence both back to surface. After a short period of time determined by the flow rate in


29


the modules are all recovered back to surface where they can be either repaired or replaced.




To reinstall the pump modules the reverse operation is performed. A new pump out seal is first installed. This allows the lowering of all the pump out modules at a controlled descent rate. It will be appreciated that if a lower pumping module is still operating correctly, this could be used to pump out the pump modules above it.




If pumping out is not preferred, or the pump out seal fails, a wire-line or slick-line could be lowered which would connect to a fishing profile


104


on top of each module to allow their recovery one by one. Alternatively, particularly in horizontal sections, the modules could be deployed and retrieved using autonomous or wireline powered tractors.




The mechanical slips


103


may be varied according to particular requirements. For example, it may need splines to prevent rotation, as when supporting torque reaction from a pump. The details of such embodiments are covered by the present invention which discloses the principle of the power transfer port, and slips and seals used on the power transfer module.





FIG. 12

shows a module where the pump inlet contains a valve


80


, which without power is held closed by a spring


81


. The sleeve


82


is either electrically or hydraulically powered to keep the valve open. When closed, and the slips


103


released, hydraulic pressure can be applied below the valve via the port


31


which works as indicated by the arrows


83


. This also works against the large moving seal


103


′ situated at the upper end of the module. Therefore rather than use a pump out seal, each individual pumping module could be pumped out, and lowered with full control. In a more sophisticated mode of operation the valve


80


could be used to lower the pump into the well. A battery operated control system fitted to the valve could monitor the rate of decent of the pump assembly and adjust the volume of fluid passed through the valve by alternately opening and closing the valve


80


. Each pump and docking station would also have identification tags so that when the pump reaches the correct power transfer station its locating slips


103


will only become active to allow the pump to be located.




The permanent electrical wiring of the docking stations depends on the module technology to be deployed. In the embodiments disclosed below, permanent magnet brushless motor technology is preferred. Typically the wiring to a docking station operated in isolation will be as shown in FIG.


29


. In this case the motor is wound for three-phase AC power, and the three windings are joined to form a so-called star point. Several such docking stations may be connected together in this way on the same three power lines if the motors are run synchronously. However greater flexibility is obtained by using permanently installed, conservatively rated, power electronics to commutate the motors individually at each station. Where only a few pumps are required it may be feasible to wire the docking stations separately back to surface.




Referring to

FIGS. 14

to


23


there are shown various embodiments of the pumping modules. Each of these will be described in more detail as follows.





FIG. 14

shows the docking station


22


and embedded coils


21


. The pump, of centrifugal type, comprises an inner stator


40


and an outer rotor


41


. The module locates in the profile


22


and allows flow to pass through it via ports


42


. The pump rotor


41


sits in a thrust bearing housing


43


and is supported by bearings


43


′. The stator


40


is stabilized at the top by a support


40


′.




Permanent magnets


41


′ are mounted on the circumference of the rotor, and in conjunction with the coils


21


form a brushless dc motor whose operating principles are well known in the art. The magnets are protected from the well fluids by means of a thin non-magnetic sleeve made for example from stainless steel or composite material. The inner bore of the docking port opposite the coils


21


is similarly protected, with the structural strength of the tubing being maintained by the coil core and outermost housing. It is an advantage of this type of motor and other permanent magnet motor types and their associated electrical drives that they may be designed with a relatively large gap between magnets


41


′ and coils


21


. This permits robust construction with good electro-mechanical performance. By contrast the most widely-used downhole pump motors are of the well-known induction motor type. This requires transformer action between coils


21


and coils on the stator. This transformer action is gravely weakened with large gaps and renders induction motors non-preferred for the purposes of the present invention.




The pump vanes may be made metallic as commonly found, or made of damage resistant composite material. It will be apparent that the concentric motor-pump arrangement is applicable to other pump types that may be used in this application such as but not restricted to positive displacement pumps, turbine pumps, impeller pumps.




Where the tubing diameter restricts the concentric design lift or flow rate capacity or where it is preferred to incorporate a conventional pump product, or it is preferred to have the pump rotate internal to its stator then the motor and pump can be separated along the axis of the tubing, with the pump above or below the motor.

FIG. 15

shows an embodiment of such a pumping module with stator coils


21


and rotor magnets


41


.





FIG. 16

shows an alternative pumping arrangement where the docking station has a valve


60


which allows fluid to be produced adjacent to the pump. This is particularly important in long horizontal sections of a well where it is preferable to even the drawdown along the length of the reservoir.




Referring to

FIG. 17

, in an alternative arrangement the module locates using an ID tag


1000


in the tool housing and tag


1001


in the deployed module, and slips


103


and seal


103


′ hold the pump stationary against the tubing and withstand reactive torque and thrust loads that the module is subjected too. Flow passes through from outside the tubing via ports


60


.





FIGS. 18



a


and


b


show a further embodiment of a pumping assembly. The pump inlet contains a valve


80


, which without power is held closed by a spring


81


. The valve seals a conduit with runs through the pump. The sleeve


82


is either electrically or hydraulically powered to keep the valve open. When closed, and the landing profile


22


released, hydraulic pressure can be applied below the valve via the port


31


which works as indicated by the arrows


83


. This also works against the large moving seal


85


situated at the upper end of the module. Therefore rather than use a pump out seal, each individual pumping module could be pumped out, and lowered with full control. In a more sophisticated mode of operation the valve


80


could be used to lower the pump into the well. A battery operated control system fitted to the valve could monitor the rate of decent of the pump assembly and adjust the volume of fluid passed through the valve by alternately opening and closing the valve


80


. Each pump and docking station would also have identification tags so that when the pump reaches the correct docking station its locating dogs will only become active to allow the pump to be landed. Instruments may be passed down the pump's conduit if desired.




In the case of a gas pipeline the pumps, concentrically or axially disposed with respect to the motor, can be turbine impellers rotated at very high rpm to compress gas to assist in transporting it along the pipeline or to re-inject it back into the oil production path to assist in reducing the hydrostatic pressure or re-energize the reservoir.





FIG. 19

shows a similar rotor and stator arrangement where the pump uses dynamic seals and gripping means to engage with the inner surface of tubing not having an engaging profile.





FIG. 20

shows a flow regulator having a local reservoir inlet valve in split view. The left side shows the throttle sleeve


202


fully open and the right side shows it fully closed. Flow control port


60


is opened and closed by an on/off solenoid shuttle valve


200


. Flow passes through the port


60


and passage


201


into the main bore


25


. At the exit of the flow passage


201


, a variable flow are can be achieved by moving the sleeve


202


towards the passage opening


201


or away from the passage opening. The precise position of sleeve


202


is maintained by the motor formed from permanent stator coils


203


and rotor magnets on the threaded sleeve


204


. Threaded sleeve


204


engages in threads on sleeve


202


, so converting motor rotation to linear actuation of sleeve


202


. When it is necessary to recover this valve to surface, solenoid valve


60


is closed and motor


203


/


204


is deactivated. A pump out seal


32


can be used to recover this assembly to surface as previously disclosed herein. Alternatively, an internal fishing profile


205


may be machined into


202


, so a wireline or coiled tubing recovery method can be employed.




Linear sleeve motion may also be obtained by direct use of a linear motor, in which the rotor magnet poles are disposed along the length of sleeve


204


instead of circumferentially, and the winding


203


topology is modified accordingly as is known in the art. Then sleeve


204


and throttle


205


move axially together and need not be separate parts. Linear motors may be used where the forces involved are not very high, and end-stops may be used to restrain motion in the case of unexpected flow surges.





FIG. 21

shows a similar system, however the pump employs a gripping means to secure itself in position, as the tube has no engaging profile.





FIGS. 22

to


24


show an internally deployed sensor assembly


300


. The assembly is expandable so that when it docks it is retained in the internal profile


301


, leaving the tubing bore at full gauge. The assembly may be powered and communicate back to surface using inductive coupling through the tubing wall to permanently installed instrument wires. When it is necessary to recover the sensor, a battery powered self propelled tractor


400


can be sent into collect it or a pump out seal


32


can be used.




Next referring to

FIGS. 25

to


27


, there is shown a further embodiment of the system. A self-propelled tractor


400


is conveying an electrically powered pumping module


100


into the well. It is shown having passed one docking station


22


and is continuing down the tubing to dock in the docking station


22


′. Once located and landed in the docking port


22


′ the tractor will either recharge its batteries or begin immediately to crawl its way back to surface. If it needs to recharge its batteries on the way back to surface it can stop at a docking port


22


and recharge them.




The foregoing embodiments have emphasized the application to wells.

FIG. 28

depicts the use of the invention in flow-lines connecting sub-sea wellheads


500


back to a floating production vessel


501


. Because of the horizontal and vertical distances involved it is advantageous to install booster pumps along the flow-lines' length. These are indicated by circles


502


. At each of these locations is an internal docking port


22


and an electrically driven pump similar to the devices described earlier. A further benefit of the retrievable module approach is to avoid very expensive diver and remotely operated vehicle (ROV) intervention. Referring to

FIG. 30

, the engaging profiles may be absent from the flowline, in which case the pumps are provided with dynamic gripping and/or sealing means.




The invention's main objective is to provide an economical means of performing advanced well electrical completions with greatly reduced maintenance costs and enhance flexibility. The deployment and recovery means disclosed can also be applied to non-electrical equipment such as hydraulic submersible pumps.




Alternative embodiments using the principles disclosed will suggest themselves to those skilled in the art, and it is intended that such alternatives are included within the scope of the invention, the scope of the invention being limited only by the claims.



Claims
  • 1. An oil flow line and powered device system comprising:a tube for the transportation of oil having an electrical conductor disposed along at least some of its length, and including a docking profile on its inner surface; at least one powered device including: a body shiftable along said tube; a rotor mounted rotatably in said body; magnets attached to said rotor, and means on said body engagable with the docking profile to retain said body in position along said tube.
  • 2. An oil flow line and powered device system according to claim 1 wherein the powered device includes a sealing means around the powered device to provide a seal between the outer surface of the powered device and the inner surface of the tube.
  • 3. An oil flow line and powered device system according to claim 1 wherein the powered device is a pump.
  • 4. An oil flow line and powered device system according to claim 1 wherein the tube is disposed in a borehole.
  • 5. An oil flow line and powered device system according to claim 1 wherein the tube and the powered device both have co-operating signal transfer means for signal transfer between said tube and the powered device.
  • 6. An oil flow line and powered device system according to claim 1 wherein the tube has a plurality of locating profiles upon an inner surface of the tube.
  • 7. An oil flow line and powered device system according to claim 1 wherein a plurality of said powered devices are disposed in the tube.
  • 8. An oil flow line and powered device system according to claim 1, further comprising a traction means which interacts with the inner surface of the tube so as move the powered device along the tube.
  • 9. An oil flow line and powered device system according to claim 8 wherein the powered device is a pump.
  • 10. A method of disposing and operating a powered device in a oil flow line comprising:introducing a powered device into a tube for the transportation of oil, the powered device including magnets attached to a rotor, which is rotatably mounted in the body of the powered device, the tube having an electrical conductor disposed along at least some of the length of the tube, and including a docking p profile on an inner surface of the tube, engaging the powered device with the docking profile of the tube in a manner that resists inducted torque, and supplying power to an electric power transfer means connected to the electrical conductor, and thereby inducing a force on the magnet to cause the rotor to turn, operating the powered device.
  • 11. A method of operating an oil pipeline, comprising the steps of:(a) providing along a length of tubing forming an oil pipeline a plurality of inductive power transfer stations spaced along said pipeline and electrically energized by at least one conductor in a wall of said tubing; (b) displacing a plurality of pumps along said tubing toward a remote end thereof and positioning said pumps at least at some of said stations, each of said pumps being formed with a pump body and a pump rotor having magnets cooperating with the respective power station to cause rotation of the respective rotor relative to the respective pump body and displacement of oil along said pipeline; (c) engaging each of said bodies with said tubing at a respective one of said stations to resist torque generated upon rotation of the respective rotor; and (d) de-energizing said inductive power transfer stations, disengaging said bodies from the tubing for repair of the pipeline, and displacing said pumps along said tubing away from said remote end.
  • 12. The method defined in claim 11 wherein said pumps are displaced along said tubing away from said remote end by pressurizing said tubing between said pumps and said remote end with a liquid pressure sufficient to displace said pumps.
  • 13. The method defined in claim 11 wherein said pumps are displaced in said tubing by a crawler engaging an inner wall of said tubing and said crawler has a rechargeable power source, said method further comprising the step of recharging said power source by positioning said crawler at one of said power transfer stations and electrically energizing same.
Priority Claims (2)
Number Date Country Kind
0004487 Feb 2000 GB
0005330 Mar 2000 GB
US Referenced Citations (6)
Number Name Date Kind
4191248 Heubsch et al. Mar 1980 A
4687054 Russell et al. Aug 1987 A
5542472 Pringle et al. Aug 1996 A
5971072 Huber et al. Oct 1999 A
6032734 Telfer Mar 2000 A
20010035288 Brockman et al. Nov 2001 A1
Foreign Referenced Citations (3)
Number Date Country
2314363 Dec 1997 GB
2334540 Aug 1999 GB
WO 9846854 Oct 1998 WO