Patent US154453A successfully refreshed from Google Patents.
US3801730A
Expired / Lapsed
US
⏱️ 0.0 years remaining
High voltage cable splice with provision for testing the insulation thereof and method of making same
Assignee: General Electric Co
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Filing: 1973-05-23
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Granted: 1974-04-02
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Expires: 1993-05-23
Abstract
Abstract A cable splice is constructed in such a way that insulant within the splice can be checked by means of a high potential applied thereto without stressing the previously-existing cable insulation in locations outside the splice. About suitably prepared ends of two cable sections, there is molded a tubular section of insulant having a tubular metal sleeve imbedded in the insulant near its outer periphery. The insulant has a first external surface portion surrounding the imbedded sleeve and second and third surface portions extending, respectively, between the ends of the first surface portion and the metal sheaths of the cable sections. Tubular metal shielding is applied to the first surface portion in a position to surround the ends of the sleeve. Semiconductive voltage-grading coatings are applied to the second and third surface portions to electrically interconnect the shielding and the sheaths. The electrical properties of the splice are then tested by applying a high potential test voltage between the imbedded sleeve and the cable conductor while the cable conductor and cable sheaths are maintained at ground potential and the shielding is maintained at substantially the potential of the imbedded sleeve. After this testing, low resistance electrical connections are provided between the shielding and the metal sheaths.
Inventors
- 👤 R Nakata
- 👤 M Ouyang
- 👤 W Starr
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 09:39
CPC Classifications
H; H02; H02G; H02G15/00; H02G15/08; H02G15/18; H02G15/184; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49004
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
302 words
A method of making a splice between two cable sections, each of which comprises: a conductor, electrical insulation surrounding the conductor, and a tubular metal sheath surrounding said insulation, the conductor having an exposed end extending beyond the end of said insulation and the insulation having an exposed end extending beyond the end of said sheath; said method comprising the steps of: a. electrically and mechanically joining the exposed ends of the two conductors, b. molding about said exposed conductor ends and said exposed insulation ends a tubular section of insulant, near the outer periphery of which is located a tubular metal sleeve that is imbedded within said insulant, surrounds said exposed conductor ends in radially-spaced relationship thereto, and is spaced from said metal sheaths; said tubular section of insulant having a first external surface portion surrounding said sleeve and second and third external surface portions extending, respectively, between the ends of said first external surface portion and said metal sheaths, c. applying to said first external surface portion tubular metal shielding that surrounds the ends of said sleeve and extends axially outward past said sleeve ends, d. providing on said second and third external surface portions voltage-grading means acting when the test voltage of (e) is applied to reduce the electrical stress concentrations on said second and third surface portions and in the portions of insulant bounded by and generally axially aligned with said second and third surface portions, e. testing the electrical properties of said splice by applying a high-potential test voltage between said sleeve and said conductors while said conductors and said sheaths are maintained at a potential near ground potential and said shielding is maintained at substantially the potential of said sleeve, f. and, after said testing, providing low resistance connections between said shielding and said metal sheaths.
Claim 2
Independent Claim
302 words
A method of making a splice between two cable sections, each of which comprises: a conductor, electrical insulation surrounding the conductor, and a tubular metal sheath surrounding said insulation, the conductor having an exposed end extending beyond the end of said insulation and the insulation having an exposed end extending beyond the end of said sheath; said method comprising the steps of: a. electrically and mechanically joining the exposed ends of the two conductors, b. molding about said exposed conductor ends and said exposed insulation ends a tubular section of insulant, near the outer periphery of which is located a tubular metal sleeve that is imbedded within said insulant, surrounds said exposed conductor ends in radially-spaced relationship thereto, and is spaced from said metal sheaths; said tubular section of insulant having a first external surface portion surrounding said sleeve and second and third external surface portions extending, respectively, between the ends of said first external surface portion and said metal sheaths, c. applying to said first external surface portion tubular metal shielding that surrounds the ends of said sleeve and extends axially outward past said sleeve ends, d. providing on said second and third external surface portions voltage-grading means acting when the test voltage of (e) is applied to reduce the electrical stress concentrations on said second and third surface portions and in the portions of insulant bounded by and generally axially aligned with said second and third surface portions, e. testing the electrical properties of said splice by applying a high-potential test voltage between said sleeve and said conductors while said conductors and said sheaths are maintained at a potential near ground potential and said shielding is maintained at substantially the potential of said sleeve, f. and, after said testing, providing low resistance connections between said shielding and said metal sheaths.
Claim 3
Dependent Claim
24 words
The method of claim 1 in which said voltage-grading means comprises coatings of voltage-grading material that, respectively, electrically interconnect said shielding and said sheaths.
Claim 4
Dependent Claim
68 words
The method of claim 1 in which: a. said tubular section of insulant is provided with a conductive lead that is electrically connected to said metal sleeve and extends generally radially outward therefrom through insulant external to said sleeve, b. said testing is effected by connecting a high potential to said lead, c. and said lead is electrically connected to one of said metal sheaths after said testing.
Claim 5
Dependent Claim
63 words
The method of claim 3 in which said lead is detachably connected to said one metal sheath, thereby allowing said connection to be broken so that: a. said sleeve can assume a different potential from said sheath while said conductor is energized and b. a voltage-measuring device can be connected between said lead and said one sheath to detect corona in said splice.
Claim 6
Dependent Claim
105 words
The method of claim 1 in which: a. prior to said molding step, said tubular metal sleeve is positioned around said exposed conductor ends and within a mold having a generally cylindrical interior surface and is maintained spaced from said cylindrical surface by electrical insulating members provided between the outer periphery of the sleeve and said cylindrical surface, b. insulant in fluid form is injected into said mold to fill the spaces within said mold internally and externally of said sleeve, c. and thereafter said insulant is allowed to set and form within said mold said tubular section of insulant with said sleeve imbedded therein.
Claim 7
Dependent Claim
34 words
The method of claim 5 in which: a. said sleeve is perforated, and b. insulant is injected into the mold from a point radially outside said sleeve and through the perforations in said sleeve.
Claim 8
Dependent Claim
276 words
A splice joining two cable sections, each comprising: a conductor, electrical insulation surrounding the conductor, and a tubular metal sheath surrounding said insulation, the conductor having an exposed end extending beyond the end of said insulation and the insulation having an exposed end extending beyond the end of said sheath; said splice comprising: a. means electrically and mechanically joining the exposed ends of the two conductors, b. a tubular section of insulant surrounding said exposed conductor ends and said exposed insulation ends and bonded thereto, c. a metal sleeve imbedded within the insulant of said tubular section near the outer periphery of said insulant, said sleeve surrounding said exposed conductor ends in radially-spaced relation thereto and being spaced from said metal sheaths, d. said tubular section of insulant having a first external surface portion surrounding said sleeve and second and third external surface portions extending, respectively, between the ends of said first external surface portion and said metal sheaths, e. metal shielding on said first external surface portion surrounding and extending axially outwardly past the ends of said sleeve but being separated from said sleeve by the insulant of said tubular section of insulant, f. voltage-grading means on said second and third external surface portions for reducing the electrical stress concentrations on said second and third surface portions when a test voltage is applied between said metal shielding and said sheaths while said sheaths are near ground potential, g. and a conductive lead electrically connected to said sleeve and extending through insulant external to said sleeve for providing a connection through which high potential can be applied to said sleeve for electrically testing said insulant section.
Claim 9
Dependent Claim
276 words
A splice joining two cable sections, each comprising: a conductor, electrical insulation surrounding the conductor, and a tubular metal sheath surrounding said insulation, the conductor having an exposed end extending beyond the end of said insulation and the insulation having an exposed end extending beyond the end of said sheath; said splice comprising: a. means electrically and mechanically joining the exposed ends of the two conductors, b. a tubular section of insulant surrounding said exposed conductor ends and said exposed insulation ends and bonded thereto, c. a metal sleeve imbedded within the insulant of said tubular section near the outer periphery of said insulant, said sleeve surrounding said exposed conductor ends in radially-spaced relation thereto and being spaced from said metal sheaths, d. said tubular section of insulant having a first external surface portion surrounding said sleeve and second and third external surface portions extending, respectively, between the ends of said first external surface portion and said metal sheaths, e. metal shielding on said first external surface portion surrounding and extending axially outwardly past the ends of said sleeve but being separated from said sleeve by the insulant of said tubular section of insulant, f. voltage-grading means on said second and third external surface portions for reducing the electrical stress concentrations on said second and third surface portions when a test voltage is applied between said metal shielding and said sheaths while said sheaths are near ground potential, g. and a conductive lead electrically connected to said sleeve and extending through insulant external to said sleeve for providing a connection through which high potential can be applied to said sleeve for electrically testing said insulant section.
Claim 10
Dependent Claim
25 words
The splice of claim 7 in which said voltage-grading means comprises coatings of semiconductive voltage-grading material that, respectively, electrically interconnect said shielding and said sheaths.
Claim 11
Dependent Claim
22 words
The splice of claim 7 in combination with means electrically interconnecting said lead and said shielding during electrical testing of said insulant.
Claim 12
Dependent Claim
44 words
The splice of claim 7 in which said metal sleeve has at its opposite ends edges that are imbedded in said insulant and are rounded to reduce electrical stress concentrations thereadjacent when a high potential is applied to said sleeve during said electrical testing.
Claim 13
Dependent Claim
233 words
A splice joining two cable sections, each comprising: a conductor, electrical insulation surrounding the conductor, and a tubular metal sheath surrounding said insulation, the conductor having an exposed end extending beyond the end of said insulation and the insulation having an exposed end extending beyond the end of said sheath; said splice comprising: a. means electrically and mechanically joining the exposed ends of the two conductors, b. a tubular section of insulant surrounding said exposed conductor ends and said exposed insulation ends and bonded thereto, c. a metal sleeve imbedded within the insulant of said tubular section near the outer periphery of said insulant, said sleeve surrounding said exposed conductor ends in radially spaced relation thereto and being spaced from said metal sheaths, d. said tubular section of insulant having a first external surface portion surrounding said sleeve and second and third external surface portions extending, respectively, between the ends of said first external surface portion and said metal sheaths, e. metal shielding on said first external surface portion surrounding and extending axially outwardly past the ends of said sleeve but being separated from said sleeve by the insulant of said tubular section of insulant, f. low resistance electrical connections between said shielding and said metal sheaths, g. and a conductive lead electrically connected to said sleeve, extending through insulant external to said sleeve, and electrically connected to one of said metal sheaths.
Claim 14
Dependent Claim
233 words
A splice joining two cable sections, each comprising: a conductor, electrical insulation surrounding the conductor, and a tubular metal sheath surrounding said insulation, the conductor having an exposed end extending beyond the end of said insulation and the insulation having an exposed end extending beyond the end of said sheath; said splice comprising: a. means electrically and mechanically joining the exposed ends of the two conductors, b. a tubular section of insulant surrounding said exposed conductor ends and said exposed insulation ends and bonded thereto, c. a metal sleeve imbedded within the insulant of said tubular section near the outer periphery of said insulant, said sleeve surrounding said exposed conductor ends in radially spaced relation thereto and being spaced from said metal sheaths, d. said tubular section of insulant having a first external surface portion surrounding said sleeve and second and third external surface portions extending, respectively, between the ends of said first external surface portion and said metal sheaths, e. metal shielding on said first external surface portion surrounding and extending axially outwardly past the ends of said sleeve but being separated from said sleeve by the insulant of said tubular section of insulant, f. low resistance electrical connections between said shielding and said metal sheaths, g. and a conductive lead electrically connected to said sleeve, extending through insulant external to said sleeve, and electrically connected to one of said metal sheaths.
Claim 15
Dependent Claim
63 words
The splice of claim 11 in which said conductive lead is detachably connected to said metal sheath, thereby allowing said connection to be broken so that: a. said sleeve can assume a different potential from said sheath while said conductor is energized and b. a voltage-measuring device can be connected between said lead and said one sheath to detect corona in said splice.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-04-01 | 1977-10-01 | 1978-04-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-04-01 | 1981-10-01 | 1982-04-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-04-01 | 1985-10-01 | 1986-04-02 | $7700.00 | Window Closed / Lapsed |