Cover assemblies and methods for covering electrical cables and connections

Patent metadata

Field	Value
Publication number	US-9780549-B2
Application number	US-201514856850-A
Country	US
Kind code	B2
Filing date	Sep 17, 2015
Priority date	Sep 17, 2015
Publication date	Oct 3, 2017
Grant date	Oct 3, 2017

Abstract

A pre-expanded cover assembly for protecting a cable splice connection including a cable, the cable including an electrical conductor surrounded by a cable insulation layer, includes a splice body assembly and a removable holdout. The splice body assembly includes a tubular, cold-shrinkable, electrically insulative, elastomeric splice body having an interior surface defining an interior passage. The splice body assembly further includes a tubular layer of a conformable medium pre-mounted on the interior surface of the splice body. The conformable medium is a flowable material having a high electrical permittivity. The splice body assembly is mounted on the holdout such that the holdout maintains the splice body in an elastically radially expanded state, and the holdout is selectively removable from the splice body to permit the splice body to elastically radially contract. The layer of the conformable medium is positioned and configured such that, when the pre-expanded cover assembly is positioned adjacent the cable splice connection, the holdout is removed from the splice body, and the splice body elastically radially contracts onto the cable splice connection, the layer of the conformable medium will be radially interposed between and engage each of the interior surface of the splice body and an opposing interface surface of the cable insulation.

First claim

That which is claimed is:

1. A pre-expanded cover assembly for protecting a cable splice connection including a cable, the cable including an electrical conductor surrounded by a cable insulation layer, the pre-expanded cover assembly comprising:
a splice body assembly including:
a tubular, cold-shrinkable, electrically insulative, elastomeric splice body having an interior surface defining an interior passage; and
a tubular layer of a conformable medium pre-mounted on the interior surface of the splice body, wherein the conformable medium is a flowable material having a high electrical permittivity; and

a removable holdout, wherein the splice body assembly is mounted on the holdout such that the holdout maintains the splice body in an elastically radially expanded state, and the holdout is selectively removable from the splice body to permit the splice body to elastically radially contract;
wherein the layer of the conformable medium is positioned and configured such that, when the pre-expanded cover assembly is positioned adjacent the cable splice connection, the holdout is removed from the splice body, and the splice body elastically radially contracts onto the cable splice connection, the layer of the conformable medium will be radially interposed between and engage each of the interior surface of the splice body and an opposing interface surface of the cable insulation.

2. The pre-expanded cover assembly of claim 1 wherein the splice body includes a tubular primary insulation layer formed of extruded silicone or ethylene propylene diene monomer (EPDM) rubber.

3. The pre-expanded cover assembly of claim 2 wherein the splice body further includes a semiconductor layer covering an outer surface of the primary insulation layer.

4. The pre-expanded cover assembly of claim 1 wherein the conformable medium is a mastic.

5. The pre-expanded cover assembly of claim 4 wherein the mastic has a dielectric constant of at least about 10.

6. The pre-expanded cover assembly of claim 5 wherein the mastic has a dielectric constant in the range of from about 15 to 25.

7. The pre-expanded cover assembly of claim 4 wherein:
the splice body includes a tubular primary insulation layer formed of an electrically insulating elastomer, the primary insulation layer extending from a first axial end to an opposed second axial end;
the interior passage terminates at the first and second axial ends;
the tubular layer of mastic extends continuously from the first axial end to the second axial end.

8. The pre-expanded cover assembly of claim 4 wherein the mastic is a silicone rubber-based mastic that has a plasticity number in the range of from about 150 to 650 according to ISO 7323 and is deformable at all temperatures in the range of −20° C. to 50° C.

9. The pre-expanded cover assembly of claim 8 wherein the mastic has a dielectric strength in the range of from about 250 Volts/mil to 700 Volts/mil.

10. The pre-expanded cover assembly of claim 1 wherein the holdout includes a tubular holdout formed by a helically wound strip, and the holdout is configured to be removed from the splice body assembly by pulling the strip.

11. The pre-expanded cover assembly of claim 1 wherein:
the splice body includes a tubular primary insulation layer formed of an electrically insulating elastomer, the primary insulation layer extending from a first axial end to an opposed second axial end;
the interior passage terminates at the first and second axial ends;
the splice body further includes an integral, tubular inner elastomeric layer extending continuously from the first axial end to the second axial end and radially interposed between the primary insulation layer and the conformable medium; and
the inner elastomeric layer is formed of an elastomer having high permittivity.

12. The pre-expanded cover assembly of claim 1 further including a tubular Faraday cage sleeve mounted on the holdout and radially interposed between the holdout and the conformable medium.

13. The pre-expanded cover assembly of claim 1 further including a conformable, flowable electrically insulating medium pre-mounted on the interior surface of the splice body.

14. A method of manufacturing a pre-expanded cover assembly for protecting a cable splice connection including a cable, the cable including an electrical conductor surrounded by a cable insulation layer, the method comprising:
mounting a tubular layer of a conformable medium on a removable holdout, wherein the conformable medium is a flowable material having a high electrical permittivity; and thereafter
mounting a tubular, cold-shrinkable, electrically insulative, elastomeric splice body on the holdout over the conformable medium such that the holdout maintains the splice body in an elastically radially expanded state and an interior surface of the splice body defines an interior passage and engages the conformable medium;
wherein the holdout is selectively removable from the splice body to permit the splice body to elastically radially contract; and
wherein the layer of the conformable medium is positioned and configured such that, when the pre-expanded cover assembly is positioned adjacent the cable splice connection, the holdout is removed from the splice body, and the splice body elastically radially contracts onto the cable splice connection, the layer of the conformable medium will be radially interposed between and engage each of the interior surface of the splice body and an opposing interface surface of the cable insulation.

15. The method of claim 14 including forming the splice body, wherein:
the splice body includes a tubular primary insulation layer formed of extruded silicone or ethylene propylene diene monomer (EPDM) rubber; and
forming the splice body includes extruding a tube of EPDM rubber and cutting the tube of EPDM rubber to form the primary insulation layer.

16. The method of claim 15 wherein:
the splice body further includes a semiconductor layer covering an outer surface of the primary insulation layer; and
forming the splice body includes co-extruding the tube of EPDM rubber and a tube of semiconductive elastomer to form a combined tube, and cutting the combined tube to form the primary insulation layer and the semiconductor layer.

17. The method of claim 15 wherein:
the splice body further includes a semiconductor layer covering an outer surface of the primary insulation layer; and
forming the splice body includes applying a semiconductor coating to an outer surface of the tube of EPDM rubber by painting, spraying or dipping to form the semiconductor layer.

18. The method of claim 15 wherein:
the splice body includes a tubular primary insulation layer formed of an electrically insulating elastomer, the primary insulation layer extending from a first axial end to an opposed second axial end;
the interior passage terminates at the first and second axial ends;
the splice body further includes an integral, tubular inner elastomeric layer extending continuously from the first axial end to the second axial end and radially interposed between the primary insulation layer and the conformable medium;
the inner elastomeric layer is formed of an elastomer having high permittivity; an
the method includes forming the splice body by co-extruding the primary insulation layer and the inner elastomeric layer.

19. The method of claim 14 further including mounting a tubular Faraday cage sleeve on the holdout radially between the holdout and the conformable medium.

20. A method

Assignees

• Tyco Electronics Corp
• Tyco Electronics Shanghai Co Ltd
• Te Connectivity Corp

Inventors

• Yaworski Harry
• Tse Alan
• Yang Lizhang

Classifications

• H01B3/28 Primary

  natural or synthetic rubbers · CPC title

• H02G15/1833

  formed of helically wound strip with adjacent windings, which are removable by applying a pulling force to a strip end · CPC title

• H02G15/013

  Sealing means for cable inlets (inlets for cables filled with, or surrounded by, gas or oil H02G15/32) · CPC title

• H02G15/184

  with devices for relieving electrical stress · CPC title

• H02G15/08 Primary

  Cable junctions (for gas or oil filled cables H02G15/24) · CPC title