Electricity: conductors and insulators – Conduits – cables or conductors – Combined
Patent
1997-02-25
1998-10-13
Reichard, Dean A.
Electricity: conductors and insulators
Conduits, cables or conductors
Combined
174 75B, 174DIG8, H02G 15064, H02G 15184
Patent
active
058214593
DESCRIPTION:
BRIEF SUMMARY
The present invention relates to a power cable splice.
BACKGROUND OF THE INVENTION
A medium-voltage or high-voltage electrical power cable includes a conductor, insulation on the conductor, a semiconductive screen, a metal screen, and an outer sheath.
In order to splice together two such power cables, an end portion of each of them is prepared so as to strip the semiconductive screen, the insulation, and the conductor in successive steps and over suitable lengths, with the metal screen itself optionally being stripped. The stripped conductors are then electrically and mechanically connected together by means of a connector. Over the end portions of the cables, the removed screens and the usually removed outer sheath are reconstituted by means of firstly a splice body surrounding the connector and extending on either side thereof, secondly electrical shielding on the splice body, and optionally thirdly an outer protection that covers the electrical shielding and that extends over the end of the outer sheath of each cable.
Splices implemented in this way are disclosed in particular in Documents FR-A-2 436 519 and U.S. Pat. No. 4,742,184. In such a known splice, the splice body is a tubular element comprising at least two layers formed by an insulating main layer and a semiconductive outer layer.
In the splice disclosed in Document FR-A-2 436 519, the splice body is shrink-fittable, and in particular heat-shrinkable. It may include a voltage-gradient inner layer which is semiconductive or has non-linear electrical resistivity characteristics, or which includes a fluid coating such as a mastic. Furthermore, before the splice body is installed, the space adjacent to the stripped and interconnected conductors may be provided with a filler material which may be a silicone grease, a mastic, or a meltable glue, and may have insulating, conductive, or semiconductive properties, for filling any voids that remain under the splice body as installed, so as to minimize the risks of insulation breakdown due to the air in certain voids ionizing.
In the splice disclosed in Document U.S. Pat. No. 4,742,184, the splice body includes a semiconductive inner layer, and the electrically interconnected cables are provided firstly with a split semiconductive elastomer tube mounted on the connector, and secondly with an insulating elastomer tube mounted on the stripped insulation of each of the cables. The tubes adapt the outside diameter of the cables to fit the inside diameter of the splice body. Accordingly, they are chosen as a function of the cables used and/or of the connector used, so as to couple the layers of the splice body to the corresponding layers of the cables. The semiconductive elastomer tube also co-operates with the semiconductive inner layer of the splice body to place outside the influence of the electric field any air gaps between the splice body and the stripped and interconnected conductors. The semiconductive inner layer extends for this purpose along the semiconductive elastomer tube and over the facing end of each of the two insulating tubes.
Installing those known means for minimizing the risk of insulation breakdown in power cable splices is time-consuming and/or difficult or sometimes even dangerous when a flame is used for shrinking the heat-shrinkable splice body, and, once installed, they may be moved, or removed in part during installation of the splice body when said splice body is mechanically shrink-fittable.
SUMMARY OF THE INVENTION
An object of the invention is to provide means that avoid those problems, that are very easy and quick to install, that are adapted to any type of connector and to any type of cable, and that significantly improve the breakdown strength of the splice.
The invention provides a power cable splice including: semiconductive screen, a metal screen, and an outer sheath, and has an end portion that has been stripped in successive steps; said connector; the stripped insulation of the cables; and to the metal screens of the cables; flexible two-layer composite plate whi
REFERENCES:
patent: 3412200 (1968-11-01), Virsberg et al.
patent: 3673311 (1972-06-01), Misare
patent: 3692922 (1972-09-01), Sugimoto et al.
patent: 3717717 (1973-02-01), Cunningham et al.
patent: 3777048 (1973-12-01), Traut
patent: 3952604 (1976-04-01), Penneck
patent: 4164620 (1979-08-01), Hervig
patent: 4487994 (1984-12-01), Bahder
patent: 4698458 (1987-10-01), Parmigiani et al.
patent: 5043538 (1991-08-01), Hughey, Jr. et al.
Brackeniers Christophe
Cauwel Johan
Cheenne-Astorino Annie
Alcatel Cable France
Reichard Dean A.
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