Method and apparatus for blocking pathways between a power cable and the environment

Information

  • Patent Grant
  • 6517366
  • Patent Number
    6,517,366
  • Date Filed
    Thursday, December 6, 2001
    23 years ago
  • Date Issued
    Tuesday, February 11, 2003
    21 years ago
Abstract
A cable connector, connector apparatus and method for introducing fluid to a cable. The cable connector, connector apparatus and method configured to form an electrically resistive barrier between components internal to the connector and the environment surrounding the connector after the introduction of the fluid. In one embodiment, a connector comprises a chamber adapted to affix a cable internal to the chamber, wherein the chamber is in fluidic communication with an injection port. The connector further comprises a valve operable to restrict fluid from entering the injection port from the chamber when a fluid source discontinues the introduction of fluid into the injection port. In another embodiment, a method of the present invention involves the application of an insulating material into an injection port of a connector following the application of a dielectric fluid, thereby forming an electrically resistive barrier between components internal to the connector and the external environment.
Description




FIELD OF THE INVENTION




The present invention relates to a remediation process for the insulation of power cables and, more particularly, to injection of dielectric enhancement component into the power cable.




BACKGROUND OF THE INVENTION




A remediation process for the insulation of high-voltage electrical power cables requires the injection of a remediation fluid into the cables. It is known in the art that remediation fluids which are most effective have viscosities less than 50 centistokes at 25° C. as these fluids must be able to flow through very small interstitial spaces over very long cable lengths and must be of small enough molecular size to diffuse into the cable insulation. In many instances, this injection process takes place while the cable is energized. When the remediation process is performed on energized cables, a class of special cable end terminations is typically used. These terminations are known as injection elbows. Injection elbows are similar to industry standard elbow-type connectors except that special ports have been designed into them to allow for the attachment of an injection plug to the elbows.




After injection of the remediation fluid is complete, the injection plug is withdrawn from the injection port and is replaced with a sealing plug. Between the time that the injection plug is removed, and the sealing plug is installed, the injection port is open, and the energized conductor of the cable is exposed. Because of the remediation fluid's low viscosity it is likely to empty out of the open injection port. Although there is no direct electrical connection between the conductor and the grounded exterior of the cable elbow, there is the danger of an indirect electrical connection being established between the conductor and the grounded exterior of the elbow.




One such indirect pathway may be formed by contaminants that have become entrained in the remediation fluid. Contaminated fluid can be drawn from the injection port as the injection plug is withdrawn or may simply flow out under the force of gravity, thereby creating partial discharging or even a complete conductive pathway to the ground plane.




A second indirect pathway is created by source molecules such as those found in low viscosity remediation fluid, water or other contaminants which may be present in the conductor. Source molecules, also referred to as particles, can ionize or form an aerosol, which may become charged in the high-voltage field. These ionized or charged particles may then accelerate towards the ground plane creating a dynamic and conductive aerial pathway.




These two known conductive pathways, as well as any other conductive pathway established between the conductor and the ground plane, can degrade or destroy the injection elbow. Therefore, a need exists to create a barrier to block the conductive pathway between the conductive portion of the cable and the ground plane to increase the life expectancy of the injection elbow.




SUMMARY OF THE INVENTION




One embodiment of the present invention is directed towards a method and apparatus for creating a barrier after the injection of remediation fluid to block the conductive pathway between the conductive portion of an energized cable and the ground plane. An injection elbow with an injection port is used to introduce remediation fluid into the energized cables. The remediation fluid is introduced into the injection port by way of an injection plug inserted into the injection port. Upon completion of the introduction of the remediation fluid, an insulation material is injected through an injection tube of the injection plug and into the injection port. This insulation material may be any of a variety of dielectric, high-viscosity fluids. The insulation material effectively blocks the conductive pathway between the conductive portion of the cable and the ground plane so as to allow removal of the injection plug without creation of a conductive pathway to allow for the insertion of a permanent plug to block the injection port and protect the injection elbow from degradation.




In another embodiment of the present invention, the injection elbow includes a flap valve located between the injection port and a fluid chamber inside the injection elbow. As fluid is introduced through the injection port, the flap valve is opened either by the fluid pressure, or by an extension on the injection plug, allowing the fluid to fill a chamber in the injection elbow. When the chamber in the fluid elbow is full and introduction of the fluid has ceased, the pressure from inside the chamber forces the flap valve to shut, thus creating a barrier between the conductor and the ground plate. The injection plug can now be removed without exposing the energized conductor which may create a degradation of the injection elbow.




In still another embodiment of the present invention, a physical barrier is incorporated in the injection plug to block the escape of remediation fluid upon discontinuing filling of the chamber of the injection elbow. This embodiment permits leaving behind the injection plug in the injection port thus eliminating a need for a permanent plug. The physical barrier of this embodiment includes a ball valve; however, a variety of gate valves or check valves, actuated manually, electronically, hydraulically, or pneumatically may be used.




In yet another embodiment of the present invention, the injection plug includes a breakable tip having a catch at its end. Upon insertion of the injection tube into the injection port, the breakable tip becomes lodged in the injection port. After discontinuing the introduction of remediation fluid into the chamber, the injection plug is removed causing the breakable tip of the injection tube to remain lodged in the injection port creating a permanent barrier in the injection port, therefore, blocking the conductive pathway between the conductive portion of the cable and the ground plane.











BRIEF DESCRIPTION OF THE DRAWINGS




The foregoing aspects and many of the attendant advantages of this invention will become more readily appreciated as the same become better understood by reference to the following detailed description, when taken in conjunction with the accompanying drawings, wherein:





FIGS. 1A and 1B

illustrate a cross-sectional side view of an injection elbow formed in accordance with one embodiment of the present invention, showing an injection plug, and a sealing plug;





FIG. 2

illustrates a cross-sectional side view of an injection elbow formed in accordance with one embodiment of the present invention, showing a flap valve at the junction of the injection port and the chamber;





FIG. 3

illustrates a cross-sectional side view of an injection plug formed in accordance with one embodiment of the present invention, showing a ball valve and a ball valve override apparatus;





FIG. 4

illustrates a cross-sectional side view of an injection plug with a ball valve formed in accordance with one embodiment of the present invention; and





FIG. 5

represents a cross-sectional side view of an injection plug formed in accordance with one embodiment of the present invention, showing an injection tube having a breakable tip and a catch.











DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT





FIGS. 1A and 1B

illustrate an injection elbow


10


formed in accordance with one embodiment of the present invention. Such an injection elbow


10


is adapted to introduce dielectric enhancement fluid into a section of power cable


2


, such as a high-voltage electric cable. Typical power cables


2


include a conductive core


4


surrounded by an insulation layer


6


. The conductive core


4


includes a plurality of electrically conductive strands


13


. Although a plurality of conductive strands


13


is preferred, a cable


2


having a single conductive strand is also within the scope of the present invention. Further, although the injection elbow


10


is illustrated as a load-break connector, other types of connectors, such as tee-body or splice-type connectors which occur at cable junctions, are also within the scope of the present invention.




The elbow


10


includes a fluid chamber


12


and an injection port


14


. The injection port


14


permits the introduction of the dielectric enhancement fluid into the cable while the cable is energized. Dielectric enhancement fluid is injected through the injection port


14


and into the fluid chamber


12


by a canal


15


, thus allowing fluid to enter the cable insulation through the interstitial spaces between the cable strands.




Still referring to

FIG. 1

, fluid enters the injection port


14


by way of an injection plug


20


. The injection plug


20


includes a conduit


24


and a stem portion


22


. In operation, the stem portion


22


is inserted into the injection port


14


to allow for the introduction of the dielectric enhancement fluid into the fluid chamber


12


. A permanent plug


16


is sized and shaped for insertion into the injection port


14


, thereby sealing the chamber


12


from the environment external to the injection elbow


10


. In operation, the permanent plug


16


is inserted into the injection port


14


after the removal of the injection plug


20


.




As noted above, it is desirable to minimize the risk of a pathway being formed between the conductive portions


4


and


6


, of the cable


2


and the external environment. In that regard, before the injection plug


20


is removed from within the injection elbow


10


, an insulation material


15


is injected into the injection port


14


. The insulation material


15


forms a barrier to block any pathway between the conductor and ground, including minimizing the risk of the formation of a conductive pathway through the injection port


14


. Thereafter, the injection plug


20


is removed from the injection port


14


, and the plug


16


is reinserted into the injection port


14


of the injection elbow


10


.




Thus, one embodiment of a method for blocking a potential pathway between the conductive core


4


of a cable


2


and a ground plane after removal of the injection plug


20


includes inserting the injection tube


22


of the injection plug


20


into the injection port


14


of the injection elbow


10


; introducing a dielectric enhancement fluid into the injection port


14


from the injection plug


20


and into the fluid chamber


12


where it surrounds the conductive core


4


and strands


13


; injecting an insulation material


15


through the injection plug


20


and into the injection port


14


, whereby the insulation material


15


forms a barrier to block the potential pathway out through the injection port


14


; and removing the injection plug


20


and replacing it with the plug


16


.




The insulation material


15


is suitably a high dielectric strength, high viscosity material. Because of the material's high viscosity, it remains in place to form a physical barrier between any conductive portion of a cable and the ground plane until the plug


16


can be installed. The insulating fluid


15


can be in the form of a foam, solid, gel, or high viscosity liquid. In one embodiment, the dielectric strength may be greater than 100 volts/mil and the viscosity may be greater than 50 centistokes (cs) at 25C. In this embodiment, the dielectric strength and viscosity should be in a range that allows the insulation material


15


to contain liquid properties. One specific example of an insulating material is Dow Corning 200® fluid. Although the present embodiment uses fluid with a viscosity of 2000 centistoke, any of a variety of high dielectric strength, high viscosity materials may be used.





FIG. 2

illustrates another embodiment of an injection elbow


110


constructed in accordance with the present invention. The injection elbow


110


is identical in materials and operation to the first embodiment described above with the exception that the injection elbow


110


includes a flap valve


130


. In one embodiment, the flap valve


130


is suitably located at the intersection of the injection port


114


and the fluid chamber


112


. The flap valve


130


may be integrally connected to the injection elbow


110


by a live hinge, or may be fastened to the injection elbow


110


by a mechanical hinge


131


. In one embodiment, the flap valve


130


is normally biased into a closed position. Although the illustrative embodiment of

FIG. 2

includes a flap valve


130


that is located near the intersection of the injection port


114


and the fluid chamber


112


, the flap valve


130


may be positioned in any location of the injection port


114


and fluid chamber


112


so long as the flap valve


130


is configured to restrict any fluidic communication from the fluid chamber


112


to the injection port


114


. For instance, the flap valve


130


may be constructed from a substantially flat member attached to the inner wall of the injection port


114


by the use of a hinge.




As dielectric enhancement fluid is introduced into the injection port


114


, the flap valve


130


is forced open by the fluid pressure of the incoming dielectric enhancement fluid, or it is physically opened by an extended length injection fitting, thereby allowing the fluid to enter or exit the chamber


112


. When introduction of the fluid has concluded, the flap valve


130


returns to the closed position, thereby creating a physical barrier between the conductive core


104


and the ground plane.




Referring now to

FIG. 3

, another embodiment of an injection plug


220


constructed in accordance with the present invention will now be described in greater detail. The injection plug


220


is identical in materials and operation to the injection plug


220


described for the first embodiment with the exception that the injection plug


220


is constructed and configured to remain attached to the injection elbow


10


, and includes a plunger assembly


239


and a valve actuator assembly


234


. The injection plug


220


is configured to remain attached to the injection elbow


10


after the introduction of dielectric enhancement fluid. As such, it should be apparent that dielectric enhancement fluid is introduced to the injection plug


220


by a removable supply source


280


. In operation, the injection plug


220


is accessed in a well known fashion and the supply source


280


is removably coupled to the injection plug


220


. After the transfer of dielectric enhancement fluid has been completed, the supply source


280


is decoupled from the injection plug


220


. Although a fixed injection plug


220


is suitable for purposes of the current embodiment of the present invention, it should be apparent that other types of injection plugs, such as temporary injection plugs, are also within the scope of the present invention.




The plunger assembly


239


includes a plunger


231


and a spring bias ball valve


232


. The plunger


231


is suitably a rod shaped member slidably disposed within the conduit


224


of the stem portion


222


. As disposed within the stem portion


222


, the plunger extends between the valve actuator assembly


234


and the ball valve


232


.




The ball valve


232


includes a spring


236


and a ball


238


. The spring


236


biases the ball


238


to a closed and sealed position, wherein the ball


238


is seated within a chamfered portion


233


located in the conduit


224


. As assembled, the ball valve


232


is biased into a closed position against the chamfered portion


233


of the conduit


224


.




As dielectric enhancement fluid is introduced into the injection plug


220


, the fluid pressure causes the ball


238


to overcome the spring force and compress the spring


236


, thereby causing the ball valve


232


to open and allow dielectric enhancement fluid to enter the injection port


14


of the injection elbow (


10


of FIG.


1


). When the flow of dielectric enhancement fluid ceases, the spring


236


biases the ball


238


of the ball valve


232


to the closed position, thereby blocking the escape of dielectric enhancement fluid and any potential pathway that may be created.




The valve actuator assembly


234


is rotatably disposed within the injection plug


220


and allows the ball valve


232


to be manually opened to permit the removal of gas or fluid from the injection elbow


10


. The valve actuator assembly


234


includes a paddle mechanism


240


with an upper paddle


242


and a lower paddle


244


. The upper paddle


242


is connected to the lower paddle


244


by a shaft


246


. The upper paddle


242


is suitably orientated at a 90° angle relative to the lower paddle


244


and is located such that the lower paddle


244


rests against the plunger


231


, which is positioned next to the ball


238


of the ball valve


232


. As the upper paddle


242


is rotated, the lower paddle


244


is urged against the plunger


231


and the ball


238


of the ball valve


232


. As the lower paddle


244


is urged against the ball


238


, the ball compresses the spring


236


to open the ball valve


232


, thereby allowing fluidic communication from the injection elbow (


10


of

FIG. 1

) into the conduit


224


.




In operation, dielectric enhancement fluid is injected through the conduit


224


of the injection plug


220


and into the injection elbow


10


. The spring


236


of the ball valve


232


is compressed by utilizing the fluid pressure of the dielectric enhancement fluid, thereby urging the ball


238


against the spring


236


. After introduction of the dielectric enhancement fluid into the injection elbow


10


is completed, the ball valve


232


is displaced into the closed position by the spring


236


. Finally, the upper paddle


242


is employed anytime the need arises for flow to move in the reverse direction of the valve's bias. The paddle can be operated such that the lower paddle


244


is urged against the ball


238


to open the ball valve


232


and allow for the removal of any air gas or fluids therein as required. At the end of the injection, the connecting tubing


280


is optionally removed, and the injection plug is optionally left in place forming a permanent barrier between the conductor and the ground plane.




Referring to

FIG. 4

, an injection plug


320


formed in accordance with another embodiment of the present invention will now be described in greater detail. The injection plug


320


illustrated in

FIG. 4

is configured in a manner similar to the embodiment depicted in FIG.


3


. For instance, the injection plug


320


includes an elongated nozzle


350


, ball valve assembly


332


, and a conduit


324


. As depicted in

FIG. 4

, the conduit


324


is configured to allow fluidic communication between a supply source


380


and an opening


381


positioned near the end of the nozzle


350


. The injection plug


320


of the present embodiment also includes a spring bias ball valve assembly


332


. In one embodiment, the nozzle


350


is selectively fastened to one end of the injection plug


320


. As shown in

FIG. 4

, the nozzle


350


may be attached to the injection plug


320


by the use of a connector


351


such as a latch, threaded connection, or the like. In yet another embodiment, the injection plug


320


comprises a rod


352


that is formed and configured to be slidedly inserted into the nozzle


350


when the nozzle


350


is attached to the injection plunger


320


.




The ball valve assembly


332


includes a spring


336


and a ball


338


. The spring


336


normally biases the ball


338


against a chamfered portion


333


formed within the nozzle


350


, thereby displacing the ball valve assembly


332


into a closed position. In operation, when the injection nozzle is fully threaded, the rod


352


extends through the nozzle


350


and displaces the ball from its seat allowing fluid, gasses or air to move in either direction. Upon completion of the injection process, the nozzle


350


can be detached from the plug


320


, thereby withdrawing the inner rod


352


from the nozzle


350


. The removal of the inner rod


352


from the nozzle


350


allows the spring


336


to move the ball


338


toward the chamfered portion


333


, thereby preventing fluidic communication from the opening


381


into the nozzle


350


.




In one embodiment, the nozzle


350


is threadably connected to the body of the injection plug


320


to permit the ball valve assembly


332


to be manually actuated between an open and a closed position by the attachment and detachment of the nozzle


350


. In the open position, the nozzle


350


is rotated inward for further engagement with the injection plug


320


. With the nozzle


350


in the open position, the ball


338


is urged against the rod


352


thereby compressing the spring


336


and opening the ball valve


332


. The embodiments of

FIGS. 3 and 4

depict two devices suitable for creating a physical barrier between the conductive core


4


and the ground plane. However, it should be apparent that a variety of gate valves or check valves, actuated manually, electronically, hydraulically, or pneumatically are also within the scope of the described embodiments of the present invention.




Referring now to

FIG. 5

, another embodiment of an injection plug


420


formed in accordance with the present invention will now be described in greater detail. The injection plug


420


of

FIG. 5

is constructed in a manner similar to the injection plug


220


depicted in FIG.


1


A. For instance, the injection plug


420


comprises a stem portion


422


, a conduit


424


internal to the injection plug


420


, and a supply source


480


. In addition, the injection plug


420


depicted in

FIG. 5

also comprises a cap


462


, wherein the cap


462


is positioned at the end of the stem portion


422


and affixed to the stem


422


by a friction type fastener or the like. As described below, the cap


462


is operable to create a barrier in the injection port of an elbow when the injection plug is removed from the injection port. The cap may be made of any flexible material such as rubber or the like. Also shown in

FIG. 5

, the stem portion


422


also comprises at least one aperture positioned on at least one side of the stem portion


422


for allowing fluidic communication between the conduit


424


and the environment external to the plug


420


.




Referring now to

FIGS. 1A and 5

, the operation of the embodiment shown in

FIG. 5

will now be described. In one embodiment, the aperture


464


is positioned near the stem portion


422


, such that when the stem portion


422


of the plug


420


is inserted into an injection port


14


of an injection elbow


10


, the aperture


464


provides for fluidic communication between the conduit


424


of the plug


420


and the chamber


12


of the elbow


10


. Once the stem portion


422


is fully inserted into the injection port


14


, a fluid may be injected into the injection port


14


via the conduit


424


. Once the injection is complete, the injection plug


420


is withdrawn partially from the injection port


14


. In the removal of the injection plug


420


, the cap


464


rests against the surface of the fluid chamber


12


and becomes lodged in the injection port


14


, thereby preventing fluidic communication between the fluid chamber


12


and the injection port


14


.




In another embodiment, the cap


462


is affixed to the end


460


of the stem portion


422


by a threaded connection. In the operation of this embodiment, when the injection plug


420


is withdrawn from the injection port


14


, the cap


462


either pulls off or is unthreaded so that the cap


462


remains in the injection port


14


of the elbow


10


. Like the above-described embodiment, cap


462


is configured with a flexible material, such that, when the injection plug


420


is removed from the injection port


14


, the cap


462


is lodged in the injection port


14


, thereby preventing fluidic communication between the fluid chamber


12


and the environment external to the elbow


10


.




While the preferred embodiment of the invention has been illustrated and described, it will be appreciated that various changes can be made therein without departing from the scope of the present invention.



Claims
  • 1. A cable connector for introducing fluid to a cable affixed in a chamber internal to the cable connector, the cable connector comprising:an injection port exposed to at least one exterior surface of the cable connector, the injection port having fluidic communication with the chamber internal to the cable connector; and a valve for allowing the passage of fluid from the injection port into the chamber, wherein the valve is operable to allow fluid to enter the chamber internal to the cable connector when the fluid is introduced into the injection port from a fluid source, and wherein the valve is operable to restrict fluid from entering the injection port from the chamber internal to the cable connector when the fluid source discontinues the introduction of fluid into the injection port, wherein the valve is a flap valve connected to the cable connector by a live hinge.
  • 2. A cable connector for introducing fluid to a cable affixed in a chamber internal to the cable connector, the cable connector comprising:an injection port exposed to at least one exterior surface of the cable connector, the injection port having fluidic communication with the chamber internal to the cable connector; and a valve for allowing the passage of fluid from the injection port into the chamber, wherein the valve is operable to allow fluid to enter the chamber internal to the cable connector when the fluid is introduced into the injection port from a fluid source, and wherein the valve is operable to restrict fluid from entering the injection port from the chamber internal to the cable connector when the fluid source discontinues the introduction of fluid into the injection port, wherein the flap valve is biased into a closed position.
  • 3. A cable connector for introducing fluid to a cable affixed in a chamber internal to the cable connector, the cable connector comprising:an injection port exposed to at least one exterior surface of the cable connector, the injection port having fluidic communication with the chamber internal to the cable connector; and a valve for allowing the passage of fluid from the injection port into the chamber, wherein the valve is operable to allow fluid to enter the chamber internal to the cable connector when the fluid is introduced into the injection port from a fluid source, and wherein the valve is operable to restrict fluid from entering the injection port from the chamber internal to the cable connector when the fluid source discontinues the introduction of fluid into the injection port, wherein the valve is a flap valve connected to the cable connector by a mechanical hinge.
  • 4. The cable connector of claim 3, wherein the flap valve is positioned at the intersection of the chamber and the injection port, and wherein the flap valve is biased into a closed position.
  • 5. An apparatus for introducing fluid to a cable, the apparatus comprising:a cable connector having an injection port exposed to at least one exterior surface of the cable connector and a chamber internal to the cable connector, wherein the chamber is adapted for affixing a cable internal to the chamber, wherein the injection port and the chamber are configured to provide fluidic communication between the chamber and injection port; and a plug adapted for insertion into the injection port of the cable connector, wherein the plug provides fluidic communication between a conduit internal to the plug and the chamber when the plug is inserted into the injection port, wherein the plug includes a valve configured to restrict fluidic communication between the conduit and the chamber if the fluidic pressure in the chamber is greater than or equal to the fluidic pressure in the conduit.
  • 6. The apparatus of claim 5, wherein the valve comprises:a ball positioned in a chamfered portion of the conduit, wherein the ball is movable relative to the side of the chamfered portion; a spring adapted to bias the ball against the side of the chamfered portion of the conduit, thereby restricting fluidic communication between the conduit and the chamber, and wherein the ball and spring are configured to allow fluidic communication from the conduit to the chamber when fluid is supplied into the conduit from a supply source.
  • 7. The apparatus of claim 6, further comprising an actuator for biasing the ball away from the side of the chamfered portion of the conduit, thereby allowing fluidic communication between the conduit and the chamber.
  • 8. The apparatus of claim 6, wherein the actuator is a manually operated actuator.
  • 9. An apparatus for introducing fluid to a cable, the apparatus comprising:a connector having a port means and a chamber means, wherein the chamber means is adapted for affixing a cable internal to the chamber, wherein the port means and the chamber means are configured to provide fluidic communication between the chamber means and the port means; and a plug means for providing fluidic communication between a fluid source and the chamber means, wherein the plug means is configured to restrict fluidic communication between the conduit and the chamber if the fluidic pressure in the chamber is greater than or equal to the fluidic pressure in the conduit.
  • 10. An apparatus for introducing fluid to a cable, the apparatus comprising:a cable connector having an injection port exposed to at least one exterior surface of the cable connector and a chamber internal to the cable connector, wherein the chamber is adapted for affixing a cable internal to the chamber, wherein the injection port and the chamber are configured to provide fluidic communication between the chamber and injection port; and a plug having a stem adapted for insertion into the injection port of the cable connector, wherein the stem is selectively affixed to the plug by a detachable fastener, the stem arranged such that a conduit in the stem is in fluidic communication with a conduit internal to the plug, and wherein the conduit in the stem is in fluidic communication with the chamber of the cable connector, the plug further comprising a rod configured to extend through the conduit in the stem, wherein the rod actuates a valve in the conduit in the stem to an open position, thereby allowing fluid to pass from the conduit in the stem to the chamber, and wherein the valve restricts the fluidic communication between the conduit of the stem and chamber when the stem is selectively detached from the plug.
  • 11. The apparatus of claim 10, wherein the rod is configured to bias the valve in the conduit of the stem to allow fluidic communication between the conduit of the stem and the chamber when the stem is selectively affixed to the plug.
  • 12. The apparatus of claim 10, wherein the detachable fastener is a threaded fastener.
  • 13. The apparatus of claim 10, wherein the valve comprises:a ball positioned in a chamfered portion of the conduit of the stem; a spring adapted to bias the ball against the side of the chamfered portion of the conduit, thereby restricting fluidic communication between the conduit in the stem and the chamber when the stem is detached from the plug.
  • 14. An apparatus for introducing fluid to a cable, the apparatus comprising:a cable connector having an injection port exposed to at least one exterior surface of the cable connector and a chamber internal to the cable connector, wherein the chamber is adapted for affixing a cable internal to the chamber, wherein the injection port and the chamber are configured to provide fluidic communication between the chamber and injection port; and a plug adapted for insertion into the injection port of the cable connector, wherein the plug provides fluidic communication between a conduit internal to the plug and the chamber of the cable connector when the plug is inserted into the injection port, wherein the plug further comprises a flexible cap operable to lodge into the injection port when the plug is removed from the injection port, thereby restricting fluid flow through the injection port.
  • 15. A method of introducing insulation material into a connector having an injection port and a chamber, wherein the chamber is formed to affix at least one cable internal to the chamber, and wherein the connector is configured to provide fluidic communication between the injection port and the chamber, the method comprising:inserting an injection plug into the injection port of the connector; and injecting the insulation material into the injection plug, thereby filling at least a portion of the injection port with the insulation material, wherein the injection of the insulation material creates an electrically resistive barrier between the chamber and a surface area external to the connector, wherein the insulation material is made from a high viscosity liquid.
  • 16. A method of introducing insulation material into a connector having an injection port and a chamber, wherein the chamber is formed to affix at least one cable internal to the chamber, and wherein the connector is configured to provide fluidic communication between the injection port and the chamber, the method comprising:inserting an injection plug into the injection port of the connector; and injecting the insulation material into the injection plug, thereby filling at least a portion of the injection port with the insulation material, wherein the injection of the insulation material creates an electrically resistive barrier between the chamber and a surface area external to the connector, wherein the insulation material is a dimethylsiloxane polymer with a viscosity greater than 50 cp at 25° C. and a dielectric breakdown strength greater than 100 volts/mil.
  • 17. A method of introducing a fluid into a connector having an injection port and a chamber, wherein the chamber is formed to affix at least one cable internal to the chamber, and wherein the connector is configured to provide fluidic communication between the injection port and the chamber, the method comprising:inserting an injection plug into the injection port of the connector; injecting a fluid into the injection plug, thereby filling at least a portion of the chamber with the fluid; and injecting an insulation material into the injection plug, thereby filling at least a portion of the injection port with the insulation material, wherein the injection of the insulation material creates an electrically resistive barrier between the injected fluid and a surface area external to the connector.
CROSS-REFERENCE TO RELATED APPLICATION

This non-provisional application claims the benefit under 35 U.S.C. §119(e) of U.S. Provisional Application No. 60/251,974, filed on Dec. 6, 2000, and titled “Method and Apparatus for Blocking Pathways Between a Power Cable and the Environment,” the subject matter of which is specifically incorporated herein by reference.

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Number Date Country
60/251974 Dec 2000 US