Separable connector for coil tubing deployed systems

Information

  • Patent Grant
  • 6213202
  • Patent Number
    6,213,202
  • Date Filed
    Monday, September 21, 1998
    26 years ago
  • Date Issued
    Tuesday, April 10, 2001
    23 years ago
Abstract
A connector permits separation of a submergible pumping system from its deployment system. The connector includes an upper assembly and a lower assembly that are connected by shear screws. A hydraulic separation mechanism is used to shear the shear screws and separate the upper and lower assemblies from a remote location.
Description




FIELD OF THE INVENTION




The present invention relates generally to the field of submergible equipment, such as pumping systems, for use in wells, such as petroleum production wells, and other submerged environments. More particularly, the invention relates to an apparatus for coupling a deployment system, such as coil tubing, to deployed equipment, such as a submergible pumping system.




BACKGROUND OF THE INVENTION




In producing petroleum and other useful fluids from production wells, a variety of component combinations, sometimes referred to as completions, are used in the downhole environment. For example, it is generally known to deploy a submergible pumping system in a well to raise the production fluids to the earth's surface.




In this latter example, production fluids enter the wellbore via perforations formed in a well casing adjacent a production formation. Fluids contained in the formation collect in the wellbore and are raised by the submergible pumping system to a collection point above the surface of the earth. In an exemplary submergible pumping system, the system includes several components such as a submergible electric motor that supplies energy to a submergible pump. This system may further include additional components, such as a motor protector, for isolating the motor oil from well fluids. A connector also is used to connect the submergible pumping system to a deployment system. These and other components may be combined in the overall submergible pumping system.




Conventional submergible pumping systems are deployed within a wellbore by a deployment system that may include tubing, cable or coil tubing. Power is supplied to the submergible electric motor via a power cable that runs along the deployment system. For example, with coil tubing, the power cable is either banded to the outside of the coil tubing or disposed internally within the hollow interior formed by the coil tubing. Additionally, other control lines, such as hydraulic control lines and tubing encapsulated conductors (TECs) may extend along or through the deployment system to provide a variety of inputs or communications with various components of the completion.




When an electric submergible pumping system is deployed in a well, it often is convenient to utilize coil tubing to support the completion equipment and to channel power and other conductors, particularly when production fluids are located a substantial distance beneath the earth's surface. However, the weight of the coil tubing, power cable, any fluid within the coil tubing, control lines and completion equipment determines the length of coil tubing that can support the completion in the well, eventually reaching the material strength limit of the tubing. Accordingly, it is desirable to minimize forces associated with deploying and retrieving a completion, so that the coil tubing may be deployed to maximum depth without risking damage to the coil tubing or power cable.




For removal of the completion from the well, such factors must be considered as adding to the load which will be exerted on the deployment system. Other loads are also encountered upon retrieval. For example, a coil tubing deployment system may be filled with an internal fluid to provide buoyancy to the power cable running therethrough. However, the “loaded” coil tubing cannot be extended as far into a well as an unloaded coil tubing deployment system, because the weight of the internal fluid places additional force on the coil tubing. The fluid also adds to the load borne by the deployment system upon retrieval. Other forces and loads may result from drag within the wellbore (such as due to integral packers and similar structures), accumulated sand or silt, rock or aggregate fall-ins, and so forth. To provide for such loads, the deployment system is generally overdesigned or the completion is positioned substantially higher in the well than the mechanical strength limits of the deployment system would otherwise dictate.




When a submergible pumping system is deployed to substantial depth relative to the strength of the coil tubing, it has been proposed to release the completion and remove the coil tubing from the well separately from the completion. A work string, such as a high tensile strength coil tubing with a fishing tool, is then run downhole and latched to the completion for removal. Conventionally, submergible pumping systems have been separated from the coil tubing at the connector used to connect the coil tubing to the completion. Conventional connectors had separable components connected by shear pins or other frangible structures. Thus, to release the deployment system from the submergible pumping system, sufficient force was exerted on the deployment system to shear the pins. However, the strength to withstand the additional load required to produce this shear force must also be built into the deployment system. Moreover, this additional load potentially can damage the coil tubing and power cable. To avoid such damage, the length of the coil tubing must again be reduced to correspondingly reduce the weight supported in the wellbore. Such limits on the depth to which the submergible pumping system can be deployed are undesirable.




It would be advantageous to have a remotely actuated separation technique for releasing a deployment system from a completion, e.g. submergible pumping system, without placing undue added forces on the deployment system during the separation operation. Such a technique for separating the deployment system from the completion would facilitate placement of the completion at greater depth within the wellbore without otherwise changing the deployment system or submergible components.




SUMMARY OF THE INVENTION




The present invention features an apparatus for connecting a submergible pumping system to a deployment system and for selectively releasing the submergible pumping system from the deployment system. In a favored configuration the system comprises a coil tubing deployment system and a downhole completion. The coil tubing deployment system is connected to the downhole completion by a connector. The connector includes an upper connector assembly and a lower connector assembly. The upper and lower connector assemblies are attached to one another. Additionally, the connector includes a separator mechanism configured for remote actuation that selectively separates the upper connector assembly from the lower connector assembly. The arrangement may be underbalanced or pressure biased into an engaged position to provide additional control on the release of the completion. The entire assembly may be field installed in a straightforward manner, thereby facilitating initial installation and deployment.




According to another aspect of the invention, a connector is provided for connecting a downhole completion to a deployment system. The connector comprises an upper connector assembly and a lower connector assembly attached thereto. The connector further includes a pressure chamber disposed between the upper connector assembly and the lower connector assemblies. A fluid line is disposed in fluid communication with the pressure chamber. Additionally, a check valve is connected to the fluid line. The check valve permits flow of fluid to the pressure chamber to separate the upper connector from the lower connector but prevents backflow through the fluid line after separation.




According to another aspect of the invention, a connector is provided for use in deploying a downhole completion. The connector includes an upper assembly and a lower assembly. A shear mechanism connects the upper assembly to the lower assembly. A plurality of conductors extend through the upper and lower assembly. Those conductors are connected across a plug having a first plug portion and a second plug portion. The connector also includes a remotely controlled separation mechanism able to simultaneously shear the shear mechanism and separate the first plug portion from the second plug portion.











BRIEF DESCRIPTION OF THE DRAWINGS




The invention will hereafter be described with reference to the accompanying drawings, wherein like reference numerals denote like elements, and:





FIG. 1

is a front elevational view of a submergible pumping system positioned in a wellbore, according to a preferred embodiment of the present invention;





FIG. 2

is a cross-sectional view of a connector, generally along its longitudinal axis according to a preferred embodiment of the present invention;





FIG. 3

is a cross-sectional view taken generally along line


3





3


of

FIG. 2

;





FIG. 4

is a cross-sectional view taken generally along line


4





4


of

FIG. 2

;





FIG. 5

is a cross-sectional view taken generally along line


5





5


of

FIG. 2

;





FIG. 6

is a cross-sectional view similar to that of

FIG. 2

but showing the connector separated;





FIG. 7

is a vertical sectional view of a mechanically opened check valve for forcing release of the assembly shown in

FIG. 2

in accordance with certain aspects of the present technique;





FIG. 8

is a sectional view of the valve of

FIG. 7

illustrated in the installed position;





FIG. 9

is a sectional view of the valve of

FIG. 7

following partial release of the assembly;





FIG. 10

is a sectional view of the valve of

FIG. 7

following full release of the assembly, and with a positive pressure on the valve to purge the hydraulic supply line;





FIG. 11

is a sectional view of the valve of

FIG. 7

following release of the purge pressure to permit the valve to reseat;





FIG. 12

is a sectional view of the valve of

FIG. 7

adapted for transmission of fluid to a downstream component; and





FIG. 13

is a sectional view of the valve of

FIG. 7

adapted for exchange of data or power signals with a downstream component.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS




Referring generally to

FIG. 1

, a system


20


is illustrated according to a preferred embodiment of the present invention. System


20


may comprise a variety of components depending upon the particular application or environment in which it is used. However, system


20


typically includes a deployment system


22


connected to a completion, such as an electric submergible pumping system


24


. Deployment system


22


is attached to pumping system


24


by a connector


26


.




System


20


is designed for deployment in a well


28


within a geological formation


30


containing fluids, such as petroleum and water. In a typical application, a wellbore


32


is drilled and lined with a wellbore casing


34


. The submergible pumping system


24


is deployed within wellbore


32


to a desired location for pumping wellbore fluids.




As illustrated, pumping system


24


typically includes at least a submergible pump


36


and a submergible motor


38


. Submergible pumping system


24


also may include other components. For example, a packer assembly


40


may be utilized to provide a seal between the string of submergible components and an interior surface


42


of wellbore casing


34


. Other additional components may comprise a thrust casing


44


, a pump intake


46


, through which wellbore fluids enter pump


36


, and a motor protector


48


that serves to isolate the wellbore fluid from the motor oil. Still further components, and various configurations, may be provided depending on the characteristics of the formation and the type of well into which the completion is deployed.




In the preferred embodiment, deployment system


22


is a coil tubing system


50


utilizing a coil tube


52


attached to the upper end of comnector


26


. A power cable


54


runs through the hollow center of coil tube


52


. Power cable


54


typically comprises three conductors for providing power to motor


38


. Additionally, at least one control line


56


preferably runs through coil tube


52


to provide input for initiating separation of connector


26


from a remote location, as will be described in detail below. Additional lines, such as fluid or conductive control lines may run through the hollow interior of coil tube


52


. Also, other types of deployment systems may be utilized with connector


26


.




Referring generally to

FIG. 2

, a cross-sectional view of connector


26


is taken generally along its longitudinal axis. The illustrated connector


26


is a preferred embodiment of a separable connector. However, a variety of connector configurations can be utilized with the present inventive system and method. Accordingly, the present invention should not be limited to the specific details described.




With reference to

FIG. 2

, connector


26


includes an upper connector head


58


having an upper threaded region


60


. A slip nut


62


is threadably engaged with threaded region


60


. Slip nut


62


cooperates with connector head


58


and a retaining slip


64


to securely grip a lower end


66


of coil tubing


52


. A plurality of seals


68


are disposed between connector head


58


and coil tubing


52


. Additionally, a plurality of dimpling screws


70


are threaded through slip nut


62


in a radial direction for engagement with lower end


66


of coil tubing


52


.




In the illustrated embodiment, power cable


54


extends through the center of coil tubing


52


into a hollow interior


72


of connector


26


. Additionally, a flat pack


74


, including control line


56


, also extends through the center of coil tubing


52


into hollow interior


72


. Flat pack


74


further includes, for example, a pair of fluid lines


76


and a conductive control line


78


, such as a tubing encapsulated conductor, or TEC.




Power cable


54


is held within hollow interior


72


by an anchor base


80


attached to connector head


58


by a plurality of fasteners


82


, such as threaded bolts, as illustrated in

FIGS. 2 and 3

. Additionally, an anchor slip


84


is disposed about power cable


54


and secured by an anchor nut


86


threadably engaged with anchor base


80


.




An upper housing


88


is threadably engaged with connector head


58


. A hydraulic manifold


90


is disposed within upper housing


88


and held between a lower internal ridge


92


of upper housing


88


and a plate


94


(see also FIG.


4


). Plate


94


is held against the upper end of hydraulic manifold


90


by a split sleeve


96


disposed between connector head


58


and plate


94


, as illustrated.




Manifold


90


includes a longitudinal opening


98


therethrough. Additionally, manifold


90


includes a plurality of fluid or conductive control line openings


100


extending longitudinally therethrough. Preferably, each opening


100


terminates at a recessed area


102


formed in manifold


90


for receiving a valve


104


. Additionally, plate


94


includes an opening through which power cable


54


and control lines


56


,


76


and


78


extend into connection with manifold


90


via couplings


106


.




Disposed within opening


98


of manifold


90


is an upper plug connector


108


of an overall plug or plug assembly


110


. Upper plug connector


108


, manifold


90


and the above described components of connector


26


comprise an upper connector assembly


112


designed for separable engagement with a lower connector assembly


114


.




Lower connector assembly


114


includes, for example, a lower housing


116


and a lower plug connector


118


of plug


110


. Lower housing


116


and lower plug connector


118


are both designed for attachment to upper connector assembly


112


. Specifically, lower housing


116


is designed to receive the lower portion of hydraulic manifold


90


. Preferably, housing


116


is further attached to upper connector assembly


112


by a plurality of shear screws


119


, or similar controlled release elements, extending radially through lower housing


116


into manifold


90


, as illustrated in

FIGS. 1 and 5

.




Plug assembly


110


also is designed for separable engagement, such that upper plug connector


108


remains with upper connector assembly


112


and lower plug connector


118


remains with lower connector assembly


114


when connector


26


is separated. As illustrated, power cable


54


is routed to upper plug connector


108


. The power cable includes a plurality of conductors


120


, typically three motor conductors, that are routed through plug assembly


110


. Each conductor also is separable along with plug assembly


110


. For example, each conductor


120


may have a separation point formed by mating male terminals


122


and female receptacles


124


formed in corresponding portions of plug assembly


110


. Conductors


120


are designed to provide power to the completion, and in the illustrated embodiment specifically to motor


38


of the electric submergible pumping system. Thus, the plug assembly permits connector


26


to be used with powered completions without causing damage upon separation of upper connector assembly


112


and lower connector assembly


114


. Preferably, lower plug connector


118


is held within a longitudinal opening of lower housing


116


by a lower plate


126


and a support


128


. In appropriate applications, a biasing member (not shown) may be provided adjacent to one or both plug connectors to urge the connectors toward electrical engagement. Similarly, hydrostatic pressures in the acting against plate


126


may be used to bias the lower plug connector


118


into engagement with upper plug connector


108


.




Separation of upper connector assembly


112


from lower connector assembly


114


is accomplished by an appropriate separator mechanism. In the preferred embodiment, separator mechanism


130


comprises control line


56


, in this case a hydraulic control line, disposed through upper connector assembly


112


and manifold


90


. Separator mechanism


130


also includes valve


104


and a fluid discharge area


132


formed on lower housing


116


to create a pressure chamber


134


between upper connector assembly


112


and area


132


. For release, pressurized hydraulic fluid is forced through control line


56


from a remote location, such as a control station at the earth's surface, to pressure chamber


134


. Valve


104


permits the pressurized fluid to act against fluid discharge area


132


to pressurize pressure chamber


134


. Upon sufficient increase in pressure acting between upper connector assembly


112


and lower connector assembly


114


, the shear mechanism, e.g. shear screws


119


, is sheared. This shearing permits separation of upper connector assembly


112


from lower connector assembly


114


, as illustrated in FIG.


6


. Simultaneously, upper plug connector


108


of plug assembly


110


is disengaged from lower plug connector


118


. Thus, the connector


26


can be separated without placement of any undue force on either coil tubing


52


or power cable


54


. Following separation, the preferred embodiment illustrated provides a predicable and uniform surface or surfaces which may be engaged by a fishing tool or similar device for removal of the completion from the well. The surfaces may define various retrieval profiles, either internal or external, such as profile


117


shown in

FIGS. 2 and 6

.




Also, other separator mechanisms could be incorporated into the present design. For example, an electrical signal could be delivered downhole to a dedicated electric pump connected to and able to pressurize chamber


134


.




It should be noted that in the illustrated embodiment, opening


98


is disposed off the axial center of manifold


90


. With this embodiment, the shear screws


119


are grouped along the side of the manifold area that receives the greatest portion of the resultant force due to pressurized fluid flowing into pressure chamber


134


. Specifically, the placement of four shear screws, as illustrated in

FIG. 5

, reduces the potential for “cocking” of manifold


90


within lower housing


116


, and thereby facilitates separation of assemblies


112


and


114


.




Upon separation, valve


104


closes control link


56


to prevent well fluid from contaminating the hydraulic fluid within control line


56


, and to prevent wellbore fluids from escaping through the fluid lines. The preferred design and functions of valve


104


are explained in detail below.




Additional valves


104


may be disposed within manifold


90


for the fluid lines


76


as illustrated for control line


56


and as further described below. The use of valves


104


prevents contamination of the fluid control lines


76


, that are disposed above lower connector assembly


114


. Optionally, valves


104


can be placed in each of the control lines


76


extending along lower connector assembly


114


to prevent contamination of the control lines below upper connector assembly


112


when separated, and to prevent the escape of wellbore fluids. It also should be noted that the fluid line


76


shown beneath such additional valves


104


in

FIG. 1

, does not enter pressure chamber


134


. Rather, it is the continuation of one of the fluid control lines


76


that provide fluid to a desired component, such as packer assembly


40


.




In operation, connector


26


is attached to deployment system


22


, e.g., coil tubing


52


, and to a downhole completion, such as electric submergible pumping system


24


. Thereafter, the entire


20


system is deployed in wellbore


32


to the desired depth. In appropriate applications, it may be desirable to lock the upper connector assembly


112


to the lower connector assembly


114


during deployment and potentially during use to avoid accidental disengagement. The connector assemblies can be locked together in a variety of ways depending on the specific design of connector


26


. For example, J-slots, supported collet locks, releasable dogs or other appropriate locking mechanisms can be used.




After properly locating the system in the wellbore, packer assembly


40


is set via one of the lines


76


, and production fluids are pumped to the surface through the annulus formed around deployment system


22


. Preferably, any locking mechanism disposed on connector


26


is released prior to setting packer assembly


40


. When it becomes necessary to service or remove pumping system


24


, connector


26


is separated to permit removal of coil tubing


52


.




The separation process is initiated by pumping hydraulic fluid through control line


56


and valve


104


to fluid discharge area


132


. When the fluid pressure in control line


56


and pressure chamber


134


rises to a sufficient level, upper connector assembly


112


begins to separate from lower connector assembly


114


by movement of manifold


90


. Upon sufficient movement of manifold


90


with respect to the walls of lower connector assembly


114


, pins


119


are sheared, freeing the upper connector assembly to be withdrawn from the lower connector assembly. It should be noted that in the preferred embodiment, the connector plugs, as well as the fluid and electrical control lines remain sealed within their respective portions of the connector following separation. Also, the foregoing arrangement permits the release of the completion via straight-pull shearing of the pins in conjunction with or without hydraulic assistance. It should also be noted that in the present embodiment, the connector system is pressure biased in an engaged condition because the pressure in control line


56


is generally lower than that present in the well.




Turning now to a presently preferred construction of valve


104


,

FIGS. 7-12

illustrate presently preferred configurations of a valve for releasing the components of the connector assemblies described above. As shown in

FIG. 7

, valve


104


is lodged within recess


290


of manifold


90


, and is held within the manifold by a retainer ring


300


secured within a groove


302


. Valve


104


generally includes a spool-type valve member


304


, a seat member


306


surrounding valve member


304


, and a seat housing


308


surrounding a portion of seat member


306


. Both valve member


304


and seat member


306


are movable, as described below, to permit the flow of fluid through the valve, and to open and close the valve selectively for normal and release operations. Moreover, member


308


is also preferably slightly movable within the valve to permit the equalization of forces within the valve assembly.




Referring more particularly now to a preferred construction of valve member


304


, member


304


includes an elongated spool


310


. Spool


310


has a seat portion


312


at its lower end, and a valve stop


314


at its upper end. Valve stop


314


is held in place by an annular extension


316


, and a retainer ring


318


. Moreover, valve stop


314


includes flow-through apertures


320


permitting fluid to flow through the stop during operation of the valve. Valve stop


314


is positioned adjacent to an upper end


322


of recess


290


as described below. At its lower side, valve stop


314


abuts a compression spring


324


which serves to bias both the valve member


304


and the seat member


306


toward mutually sealed positions. In the illustrated embodiment, seat portion


312


includes a tapered hard metallic seat surface


326


, as well as a soft elastomeric seat


328


secured in an annular position to provide sealing during a portion of the movement cycle of the valve components. This arrangement provided redundancy in the sealing of the valve member and seat member.




Seat member


306


includes an elongated fluid passageway


330


in which spool


310


is disposed. Moreover, along its length, seat member


306


forms an upper extension


332


, an enlarged central section


334


, and a lower actuating extension


336


. Seals are carried by the scat member to seal designated portions of the volumes of the valve. In the illustrated embodiment these seals include an upper T-seal


338


disposed about upper section


332


, and an intermediate T-seal


340


disposed about central section


332


. Upper T-seal


338


seals between the seat member and recess


290


. Intermediate T-seal


340


seals between the seat member and an internal surface of seat housing


306


as described more fully below. Fluid passageways


342


are formed in seat member


306


to place an outer periphery of the seat member in fluid communication with passageway


330


. In the release valve, additional passageways


344


are formed at the base of actuating extension


336


. A lower seat surface


346


is formed to contact hard and soft sealing surfaces


326


and


328


to prevent flow through the value upon closure.




Seat housing


308


is positioned intermediate recess


290


and seat member


306


. In the illustrated embodiment, seat housing


308


includes an enlarged bore


348


in which central section


334


of seat member


306


is free to slide. T-seal


340


seals central section


334


in its sliding movement within bore


348


. Seat housing


308


also includes a reduced diameter lower portion


350


surrounding actuating extension


336


of seat member


306


. An internal T-seal


352


is provided in lower portion


350


to seal against the actuating extension. Retaining ring


300


abuts lower portion


350


to maintain the seat housing in place. Below seat housing


308


, within lower recess


353


, a similar internal T-seal


354


is provided for sealing about actuating extension


336


. As described below, in certain applications such as when the valve is used for hydraulic release, seal


354


may be omitted, particularly where sealing between the actuating extension and the lower recess is not required. In the present embodiment no seal


354


is provided in the release valve to permit pressurized fluid access pressure chamber


134


.




In the embodiment illustrated in

FIG. 7

, lower recess


353


is blind, and is configured to receive actuating extension


336


of valve


104


. In the installed position shown in

FIG. 7

, manifold


90


is fully engaged in lower connector assembly


114


, such that actuating extension


336


contacts a lower end of recess


353


to force seat member


306


into an upper position along seat housing


308


. The upward movement of seat member


306


compresses spring


324


to force valve member


304


into an upper position. A free flow path is thereby defined through control line


56


, apertures


320


in valve stop


314


, inner passageway


330


, and downwardly around seat portion


312


of the valve spool. At the same time, pressure from the passageway


330


of seat member


306


is communicated to the region between central section


334


of the seat member and the lower portion


350


of the seat housing via passageways


342


. Moreover, when the valve is used for hydraulic release the lower volume defined within actuating extension


334


below the spool is in fluid communication with pressure chamber


134


below seat housing


308


. It should be noted that when the valve is mechanically held open, fluid may be permitted to flow in either direction through the valve.




Referring now to

FIG. 8

, for actuation of the valve, and release of the portions of the assembly from one another, pressure is applied at control line


56


such as via an above-ground pressure source. This pressure is transmitted through apertures


320


, through passageway


330


, into actuating extension


336


, and thereby into pressure chamber


134


. As the pressure increases, a parting force is exerted against areas adjacent to pressure chamber


134


. At this time, all valve components are in pressure equilibrium. The valve assembly and manifold


90


are thereby forced away from lower connector assembly


114


, as illustrated in FIG.


9


. Spring


324


will bias the valve member


304


to contact seat member


306


.




Following initial parting of the assembly members, valve member


304


will seat against seat member


306


as shown in FIG.


9


. Application of additional pressurized fluid within control line


56


will force the fluid through central passageway


330


, temporarily unseating the spool by relative movement of the valve member


304


and seat member


306


(within the valve recess), resulting in progressive displacement of the manifold in an upward direction under the influence of forces exerted against surfaces adjacent to pressure chamber


134


. As noted above, in the blind arrangement shown in

FIGS. 7 through 11

, T-seal


354


may be eliminated, due to the free communication of fluid between the actuating extension


336


and pressure chamber


134


.




The progressive displacement of the sections of the assembly with respect to one another may proceed under fluid pressure exerted through valve


104


until full disengagement of actuating extension


336


is obtained as shown in FIG.


10


. Thereafter, further application of fluid pressure through the valve continues to unseat valve member


304


from seat member


306


, and seat member


306


from seat housing


308


, to progressively disengage the assembly sections from one another, thereby disconnecting conductors as explained above. Alternatively, once pins


119


or similar controlled release structures are sheared or actuated, the upper and lower connector sections may be separated by relative movement of the completion equipment and the deployment system. Following such full disengagement of the valve from its lower recess, valve


104


will seat as illustrated in FIG.


11


.




Following full disengagement of the sections of the assembly, valve


104


serves as a check valve permitting purging of fluids which may infiltrate into control line


56


. In particular, as shown in

FIGS. 10 and 11

, pressure may be exerted in control line


56


to unseat the valve member and seat member from one another, permitting such purging action. Following reduction in the pressure at control line


56


, spring


324


and pressure surrounding valve member


304


, force the valve member and seat member into seated engagement with one another. It should be noted that in the present embodiment illustrated in the figures, clearance is provided between valve stop


314


and upper end


322


of recess


290


, to permit full seating of the valve and seat member on one another when connector components are separated as shown in FIG.


11


.




Various adaptations may be made to valve


104


to permit control lines, instrument lines, and so forth, to communicate between upper and lower portions of the connector assembly, while preventing flooding of such lines upon parting or release.

FIG. 12

illustrates one such adaptation incorporated into a valve of the basic structure described above. In particular, rather than the blind cavity described above used to force separation or release of the connector assembly, a fluid passageway or conduit


356


may be formed in communication with the lower fluid volume within actuating extension


336


. In the embodiment shown in

FIG. 12

, a sealed fitting


358


is provided for transmitting fluid to or from a lower component, such as a packer, slide valve, and so forth. In such arrangements, full engagement of the valve


104


during assembly of the connector system will define a flow path permitting the free exchange of fluid between manifold


90


and the lower component. Upon parting, however, T-seal


354


will prevent the exchange of pressurized fluid between pressure chamber


134


and fluid contained within the valve. It should be noted that in this embodiment, actuating extension


336


does not require fluid passageways


344


(refer to FIG.


7


), but where such passageways are present, T-seal


354


prevents the exchange of fluids between the control line and pressure chamber


134


. Upon full release of the connector assembly portions, the valve will seat, thereby preventing the flow of well bore fluids, water or other ambient fluids into line


76


. As is described above, pressure applied as line


76


of such valves will, however, permit purging of the feed lines.




Also shown in

FIG. 13

, valve


104


may be adapted for accommodating an integral electrical conductor


360


, such as for a gauge pack or other electrical device. In this adaptation, a central bore


362


is formed through valve member


304


. Conductor


360


is fed through bore


362


and terminates in a bulkhead feed-through electrical connector


364


. In the illustrated embodiment, connector


364


includes a wire plug connection


366


. Such connector arrangements are available in various forms and configurations as will be apparent to those skilled in the art. For instance, one acceptable connector is available commercially from Kemlon, an affiliate of Keystone Engineering Company of Houston, Tex., under the commercial designation K25. Other connector arrangements may include bulkhead connectors configured to prevent flooding of the conduits. Also, coaxial, multi-pin, wet-connectable, and other connectors may be employed to insure continuity of the electrical connection through valve


104


.




In a presently preferred configuration, conductor


360


extends through the valve and is in electrical connection with a tubing encapsulated conductor


368


. As in the previous embodiments, valve


104


establishes a flow path upon full engagement of manifold


90


within the assembly. In the case of the valve illustrated in

FIG. 12

equipped with an electrical conductor, the electrical conductor may be surrounded by a dialectric fluid medium, such as transformer oil. Alternatively, a sealed contact may be employed to provide a wet-connect arrangement. As the manifold is retracted from the assembly, the electrical connection is interrupted, and the upper line


78


within which the upper conductor


360


is located is closed by operation of the valve. Thereafter, the conductor is electrically isolated by the dialectric fluid within the passageway. As before, the passageway may be purged by exertion of fluid pressure within the passageway to unseat valve member


304


and seat member


306


from one another.




It will be understood that the foregoing description is of preferred embodiments of this invention, and that the invention is not limited to the specific form shown. For example, a variety of connector components can be used in constructing the connector; one or more control lines can be added; a variety of control lines, such as fluid control lines, optical fibers, and conductive control lines can be adapted for engagement and disengagement; the fluid control lines can be adapted for delivering fluids, such as corrosion inhibitors etc., to the various components of the completion; and the power cable can be routed through coil tubing or connected along the coil tubing or other deployment systems. Also, a variety of valve configurations may be employed for initial and progressive, controlled release. For example, various seals may be employed in the valve in place of the T-seals discussed above, such as metal-to-metal seals, cup seals, V packing, poly-seals and so forth. Similarly, data or power signals may be exchanged with a component of the completion via internal connections other than the plug arrangement and feed through valve structure described above. These and other modifications may be made in the design and arrangement of the elements without departing from the scope of the invention as expressed in the appended claims.



Claims
  • 1. A system for connecting a submergible pumping system to a deployment system and for selectively releasing the submergible pumping system from the deployment system, comprising:a submergible pumping system; a coil tubing deployment system comprising: a coil tubing; and a power cable disposed within the coil tubing to supply power to operate the submergible pumping system; and a connector connecting the coil tubing deployment system with the submergible pumping system, the connector having: an upper connector assembly; a lower connector assembly attached to the upper connector assembly; and a separator mechanism that may be remotely actuated to separate the upper connector assembly from the lower connector assembly.
  • 2. The apparatus as recited in claim 1, wherein the separator mechanism comprises a hydraulic line disposed through the upper connector assembly and a discharge area on the lower connector for receiving pressurized hydraulic fluid from the hydraulic line.
  • 3. The apparatus as recited in claim 2, further comprising a shear pin connecting the upper connector assembly to the lower connector assembly.
  • 4. The apparatus as recited in claim 3, further comprising a valve coupled to the hydraulic line to prevent backflow into the hydraulic line upon separation of the upper connector assembly from the lower connector assembly.
  • 5. The apparatus as recited in claim 4, further comprising a hydraulic manifold disposed in the upper connector assembly and including a recess for receiving the valve.
  • 6. The apparatus as recited in claim 5, further comprising a second hydraulic line disposed through the manifold and a second valve coupled to the second hydraulic line.
  • 7. The apparatus as recited in claim 6, further comprising a third hydraulic line disposed through the manifold and a third valve coupled to the third hydraulic line.
  • 8. The apparatus as recited in claim 1, further comprising a plurality of shear pins connecting the upper connector assembly to the lower connector assembly.
  • 9. The apparatus as recited in claim 1, further comprising a plurality of motor conductors that extend through a plug, the plug being separable and having a first plug portion disposed in the upper connector assembly and a second plug portion disposed in the lower connector assembly.
  • 10. A system for connecting a submergible pumping system to a deployment system and for selectively releasing the submergible pumping system from the deployment system, comprising:a coil tubing deployment system; a downhole completion; and a connector connecting the coil tubing deployment system with the downhole completion, the connector having: an upper connector assembly; a lower connector assembly; a shear pin connecting the upper connector assembly to the lower connector assembly; and a separator mechanism that may be remotely actuated to separate the upper connector assembly from the lower connector assembly, wherein the separator mechanism comprises a hydraulic line disposed through the upper connector assembly and a discharge area on the lower connector for receiving pressurized hydraulic fluid from the hydraulic line.
  • 11. The apparatus as recited in claim 10, further comprising a valve coupled to the hydraulic line to prevent backflow into the hydraulic line upon separation of the upper connector assembly from the lower connector assembly.
  • 12. The apparatus as recited in claim 11, further comprising a hydraulic manifold disposed in the upper connector assembly and including a recess for receiving the valve.
  • 13. The apparatus as recited in claim 12, further comprising a second hydraulic line disposed through the manifold and a second valve coupled to the second hydraulic line.
  • 14. The apparatus as recited in claim 13, further comprising a third hydraulic line disposed through the manifold and a third valve coupled to the third hydraulic line.
  • 15. A system for connecting a submergible pumping system to a deployment system and for selectively releasing the submergible pumping system from the deployment system, comprising:a coil tubing deployment system; a downhole completion; and a connector connecting the coil tubing deployment system with the downhole completion, the connector having: an upper connector assembly; a lower connector assembly attached to the upper connector assembly; a plurality of motor conductors that extend through a plug, the plug being separable and having a first plug portion disposed in the upper connector assembly and a second plug portion disposed in the lower connector assembly; and a separator mechanism that may be remotely actuated to separate the upper connector assembly from the lower connector assembly, wherein the separator mechanism comprises a hydraulic line disposed through the upper connector assembly and a discharge area on the lower connector for receiving pressurized hydraulic fluid from the hydraulic line.
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Foreign Referenced Citations (1)
Number Date Country
0 624 709 A2 Nov 1994 EP