Pressurized fluid insulation for high voltage cable

Claim 2

A stress relief connection designed for application to insulated high voltage electrical cable comprising a hollow tubular sleeve adapted to surround the insulation adjacent the bared end of an insulated high voltage electrical conductor and formed of resilient elastomeric electrically insulating material having at the end thereof remote from the bared conductor an inwardly tapered exterior surface, a generally tubular stress relief sleeve formed of a material which is at least semiconductive having an outwardly tapered interior end surface in surface-to-surface contact with the tapered exterior surface of said hollow sleeve, a rigid support housing surrounding said hollow sleeve, the interior of said hollow sleeve being an elongated annular chamber adapted to be charged with a pressurized insulating fluid to expand the inner wall of said hollow sleeve radially inwardly to establish intimate contact between the inner surface of said hollow sleeve and the outer surface of the insulation surrounding the conductor adjacent its bared end.

Claim 3

A connection as defined in claim 1 in which said hollow sleeve is provided with inlet and outlet valves to provide for purging the hollow interior of the sleeve and to fill the hollow sleeve with fluid under pressure.

Claim 4

A connection as defined in claim 1 in which said tubular stress relief sleeve is formed of resilient elastomeric material and is also hollow to have an elongated annular chamber to receive insulating fluid under pressure.

Claim 5

A connection as defined in claim 3 in which passages are provided connecting the hollow interior of said hollow tubular sleeve and the hollow interior of said stress relief sleeve.

Claim 6

A connection as defined in claim 1 in which said hollow tubular sleeve is filled with insulating fluid and permanently sealed.

Claim 7

A connection as defined in claim 5 in which said connection comprises an enclosing wall movably associated with said housing, and means for moving said wall relative to said housing to apply pressure to said hollow tubular sleeve.

Claim 8

A connection as defined in claim 1 in which said fluid is an insulating liquid.

Claim 9

A connection as defined in claim 1 in which said fluid is an insulating gas.

Claim 10

A connection as defined in claim 1 in which said connection is a cable termination, and in which said housing comprises a hollow insulator body, comprising connector means exposed at the end of said body adapted to be electrically connected to the bared end of the conductor.

Claim 11

A connection as defined in claim 1 in which said connection is for connecting the ends of two insulated high voltage cables, comprising means within said hollow tubular sleeve adapted to electrically connect the bared ends of the conductors, and in which the opposite ends of said hollow tubular sleeve are both tapered as aforesaid, and stress relief sleeves as aforesaid are provided at both ends of said hollow insulated sleeve.

Claim 12

An electrical connection comprising in combination a high voltage cable having a conductor surrounded by insulation, the conductor having an end exposed and extending beyond the end portion of the insulation, a rigid housing surrounding the end portion of the insulation, a hollow tubular resilient elastomeric sleeve having an elongated annular chamber therein interposed between the end portion of the insulation and the housing, said sleeve having at the end thereof remote from the bared conductor a tapered exterior surface, a generally tubular stress relief sleeve formed of a semi-conductive material having at an end thereof a tapered interior surface in surfac-to-surface contact with the tapered exterior surface at said hollow tubular sleeve, an insulating fluid in the chamber in said sleeve under an elevated pressure sufficient to expand the chamber defined by the hollow interior of said sleeve to force the inner wall thereof into firm surface-to-surface contact with said insulation.

Claim 13

An electrical connection comprising in combination a high voltage cable having a conductor surrounded by insulation, the conductor having an end exposed and extending beyond the end portion of the insulation, a rigid housing surrounding the end portion of the insulation, a hollow tubular resilient elastomeric sleeve having an elongated annular chamber therein interposed between the end portion of the insulation and the housing, said sleeve having at the end thereof remote from the bared conductor a tapered exterior surface, a generally tubular stress relief sleeve formed of a semi-conductive material having at an end thereof a tapered interior surface in surfac-to-surface contact with the tapered exterior surface at said hollow tubular sleeve, an insulating fluid in the chamber in said sleeve under an elevated pressure sufficient to expand the chamber defined by the hollow interior of said sleeve to force the inner wall thereof into firm surface-to-surface contact with said insulation.

Claim 14

A connection as defined in claim 11 in which said hollow sleeve is provided with inlet and outlet valves to provide for purging the hollow interior of the sleeve and to fill the hollow sleeve with fluid under pressure.

Claim 15

A connection as defined in claim 11 in which said tubular stress relief sleeve is also hollow and has an annular chamber to receive insulating fluid under pressure.

Claim 16

A connection as defined in claim 13 in which passages are provided connecting the chamber in said hollow tubular sleeve and the chamber in said stress relief sleeve.

Claim 17

A connection as defined in claim 11 in which said hollow tubular sleeve is filled with insulating fluid and permanently sealed.

Claim 18

A connection as defined in claim 15 in which said connection comprises an enclosing wall movably associated with said housing, and means for moving said wall relative to said housing to apply pressure to said hollow tubular sleeve.

Claim 19

A connection as defined in claim 11 in which said connection is a cable termination, and in which said housing is in the form of a hollow insulator body, comprising connector means exposed at the end of said body adapted to be electrically connected to the bared end of the conductor.

Claim 20

A connection as defined in claim 11 in which said connection is for connecting the ends of two insulated high voltage cables, comprising means within said hollow tubular sleeve adapted to electrically connect the bared ends of the conductors, and in which the opposite ends of said hollow tubular sleeve are both tapered as aforesaid, and stress relief sleeves as aforesaid are provided at both ends of said hollow insulated sleeve.

Claim 21

An insulated connection between two high voltage cables having end portions in which bared conductor ends project beyond the ends of insulation surrounding the conductors to define a gap between the end of said insulation, connector means in the gap electrically interconnecting the bared conductor ends, a capacitive voltage distributor comprising an elongated tubular body formed of a dielectric material having elongated tapered recesses extending into opposite ends and having a central portion provided with a through opening in which are located the bared conductor ends and the connector means, an inner conducting tube in said opening in contact with said connector means, an outer elongated conducting tube covering the outer surface of the voltage distributor, a series of short circumferentially spaced, axially staggered conducting rings extending along and around each of the tapered recesses, said rings overlapping adjacent rings and spaced radially of each other, the rings being entirely embedded in said dielectric body and having the spaces between adjacent rings being filled with the dielectric material of said body.

Claim 22

An insulated connection between two high voltage cables having end portions in which bared conductor ends project beyond the ends of insulation surrounding the conductors to define a gap between the end of said insulation, connector means in the gap electrically interconnecting the bared conductor ends, a capacitive voltage distributor comprising an elongated tubular body formed of a dielectric material having elongated tapered recesses extending into opposite ends and having a central portion provided with a through opening in which are located the bared conductor ends and the connector means, an inner conducting tube in said opening in contact with said connector means, an outer elongated conducting tube covering the outer surface of the voltage distributor, a series of short circumferentially spaced, axially staggered conducting rings extending along and around each of the tapered recesses, said rings overlapping adjacent rings and spaced radially of each other, the rings being entirely embedded in said dielectric body and having the spaces between adjacent rings being filled with the dielectric material of said body.

Claim 23

A connection as defined in claim 19 which comprises in addition an outer housing formed of conducting material in contact with said outer tube.

Claim 24

A connection as defined in claim 20 in which said cables have conducting shields extending into the housing, and means electrically connecting said shields to said housing.

Claim 25

A connection as defined in claim 21 in which the means connecting the shields and housing comprise semi-conducting resilient sleeves in the ends of said housing in surface contact with said shields.

Claim 26

A connection as defined in claim 22 in which said semi-conducting sleeves have annular pockets formed therein, and insulating fluid in said pockets at elevated pressure to expand the sleeves in full surface-to-surface contact under pressure with the inner surface of the housing and with the outer surface of the cable within said housing.

Claim 27

A connection as defined in claim 20 which comprises in addition elongated hollow sleeves formed of resilient elastomeric insulating material and having an annular chamber therein extending substantially the full length thereof, the radially outer walls of the axially inner ends of said sleeves being tapered in conformity with the taper of the recesses in the ends of said voltage distributor and received therein in surface-to-surface contact, the interior of said chambers being charged with insulating fluid under pressure effective to press the inner walls of said sleeves surrounding said chambers into surface-to-surface pressure contact with the insulation surrounding the end portions of said cables within said housing.

Claim 28

A connection as defined in claim 24, the axially outer end walls of said chambers having stress relief annular surfaces tapered radially inwardly and axially outwardly from the cable ends, the material of said end walls being semi-conductive.

Claim 29

An insulated connection between two high voltage cables having end portions in which bared conductor ends project beyond the ends of insulation surrounding the conductors to define a gap between the end of said insulation, connector means in the gap electrically interconnecting the bared conductor ends, a capacitive voltage distributor comprising an elongated tubular body formed of a dielectric having elongated tapered recesses extending into opposite ends and having a central portion provided with a through opening in which are located the bared conductor ends and the connector means, a generally tubular conducting housing having apertured end walls through which the end portions of said cables extend, the space in each end of said housing defined by the tapered wall of the recess in said voltage distributor, the outer surface of the cable, the end wall of the housing, and the radially outer wall of the housing being filled by a hollow expansible sleeve portion formed of resilient elastomeric material having an elongated annular chamber therein extending subtantially for the full length of the portion of cable insulation exposed therein, said chamber being filled with insulating fluid at elevated pressure to insure full surface-to-surface pressure contact between the inner and outer surfaces of said sleeve portion and the cable insulation and the inner surface of said housing respectively.

Claim 30

An insulated connection between two high voltage cables having end portions in which bared conductor ends project beyond the ends of insulation surrounding the conductors to define a gap between the end of said insulation, connector means in the gap electrically interconnecting the bared conductor ends, a capacitive voltage distributor comprising an elongated tubular body formed of a dielectric having elongated tapered recesses extending into opposite ends and having a central portion provided with a through opening in which are located the bared conductor ends and the connector means, a generally tubular conducting housing having apertured end walls through which the end portions of said cables extend, the space in each end of said housing defined by the tapered wall of the recess in said voltage distributor, the outer surface of the cable, the end wall of the housing, and the radially outer wall of the housing being filled by a hollow expansible sleeve portion formed of resilient elastomeric material having an elongated annular chamber therein extending subtantially for the full length of the portion of cable insulation exposed therein, said chamber being filled with insulating fluid at elevated pressure to insure full surface-to-surface pressure contact between the inner and outer surfaces of said sleeve portion and the cable insulation and the inner surface of said housing respectively.

Claim 31

A connection as defined in claim 26 comprising in addition a second sleeve portion extending axially outwardly from the outer end of each first mentioned sleeve portion, said second sleeve portions forming the axially outer ends of the annular chambers in said first mentioned sleeves and being formed of semi-conducting material and shaped to form axially tapered stress relief surfaces, the inner and outer walls of said first mentioned sleeve portions being non-conducting.

Claim 32

A connection as defined in claim 27 in which both of said second sleeve portions are also hollow and provided with annular chambers adapted to receive insulating fluid at elevated pressure to expand said second sleeve portions into full surface-to-surface contact with the outer surface of said cables and the inner surfaces of said housing.

Claim 33

A high voltage electric connection comprising an elongated generally cylindrical housing having a side wall and an end wall provided with an opening through which extends the end portion of an insulated high voltage cable, said cable having the end of its conductor bared at a point remote from said end wall and having its insulation intact for a substantial length of said cable within said housing, said housing and the insulation of said cable defining therebetween an elongated annular space, an elongated sleeve formed essentially of resilient, elastomeric insulating material occupying said space, said sleeve having an elongated annular chamber therein between radially inner and outer walls, and insulating fluid filling said chamber under elevated pressure sufficient to maintain the inner and outer walls of said sleeve in firm surface-to-surface pressure contact respectively with the radially outer surface of the insulation of the end portion of said conductor received in said housing and the inner surface of the side wall of said housing.

Claim 34

A high voltage electric connection comprising an elongated generally cylindrical housing having a side wall and an end wall provided with an opening through which extends the end portion of an insulated high voltage cable, said cable having the end of its conductor bared at a point remote from said end wall and having its insulation intact for a substantial length of said cable within said housing, said housing and the insulation of said cable defining therebetween an elongated annular space, an elongated sleeve formed essentially of resilient, elastomeric insulating material occupying said space, said sleeve having an elongated annular chamber therein between radially inner and outer walls, and insulating fluid filling said chamber under elevated pressure sufficient to maintain the inner and outer walls of said sleeve in firm surface-to-surface pressure contact respectively with the radially outer surface of the insulation of the end portion of said conductor received in said housing and the inner surface of the side wall of said housing.

Claim 35

An elongated insulating and stress relief sleeve construction for use in a high voltage cable connection, said construction comprising a first elongated sleeve section formed of resilient elastomeric insulating material provided with an elongated annular chamber therein for the reception of insulating fluid at elevated pressure, an end section operatively connected to one end of said intermediate section formed of at least semi-conducting material, said first and end sections having a tapered generally conical interface providing electrical stress relief.

Claim 36

An elongated insulating and stress relief sleeve construction for use in a high voltage cable connection, said construction comprising a first elongated sleeve section formed of resilient elastomeric insulating material provided with an elongated annular chamber therein for the reception of insulating fluid at elevated pressure, an end section operatively connected to one end of said intermediate section formed of at least semi-conducting material, said first and end sections having a tapered generally conical interface providing electrical stress relief.

Claim 37

A construction as defined in claim 30 which comprises in addition a second end section conforming to the definition of the first end section in claim 30 and operatively connected to the other end of said first section.

Claim 38

A construction as defined in claim 31 in which said end section is formed of resilient elastomeric semi-conducting material.

Claim 39

A construction as defined in claim 32 in which said end section is provided with an elongated annular chamber therein for the reception of insulating fluid at elevated pressure.