Devices and methods for electrical cable splices

Patent metadata

Field	Value
Publication number	US-11424608-B2
Application number	US-202117179200-A
Country	US
Kind code	B2
Filing date	Feb 18, 2021
Priority date	Feb 18, 2020
Publication date	Aug 23, 2022
Grant date	Aug 23, 2022

Abstract

A splice for a skin-effect effect heating cable including a primary shim configured to be shrunk over part of an insulation layer of a first portion of the heating cable, a secondary shim configured to be shrunk part of the insulation layer of a second portion of the heating cable, a connector configured to electrically couple the first portion of the heating cable and the second portion of the heating cable, and an outer cold shrink tube configured to be shrunk over the primary shim, the secondary shim, and the connector.

First claim

What is claimed is:

1. A splice system for a skin-effect effect heating cable having an insulation layer and comprising a first portion at least partially disposed in a first heating tube and a second portion at least partially disposed in a second heating tube, the splice system comprising:
a splice comprising:
a primary cold shrink shim shrunk over a first length of the insulation layer of the first portion of the heating cable;
a secondary cold shrink shim shrunk over a second length of the insulation layer of the second portion of the heating cable;
a connector electrically coupled to a first conductor of the first portion of the heating cable and a second conductor of the second portion of the heating cable; and
an outer cold shrink tube comprising an outer semiconductive layer, the outer cold shrink tube shrunk over the primary cold shrink shim, the secondary cold shrink shim, and the connector; and

a metallic pull box welded to and in electrical communication with the first heating tube and the second heating tube, the metallic pull box housing the splice, and in electrical communication with the outer semiconductive layer of the outer cold shrink tube.

2. The splice system of claim 1 , wherein the connector is a shear bolt connector.

3. The splice system of claim 1 , wherein the primary shim comprises a cold shrink silicone tube.

4. The splice system of claim 1 , wherein the secondary shim comprises a cold shrink silicone tube.

5. The splice system of claim 1 , wherein the outer cold shrink tube is a cold shrink silicone tube.

6. The splice system of claim 1 , wherein the skin-effect heating cable operates at or above five thousand volts.

7. The splice system of claim 1 , wherein the skin-effect effect heating cable operates at or above ten thousand volts.

8. The splice system of claim 1 , wherein the outer semiconductive layer of the outer cold shrink tube is in electrical contact with an outer semiconductive layer of the heating cable.

9. The splice system of claim 1 , wherein a shrunk diameter of the primary cold shrink shim is approximately equal to a diameter of the outer semiconductive layer of the heating cable.

10. The splice system of claim 1 , wherein the primary shim, the secondary shim, and the outer cold shrink tube comprise materials that are rated for at least 150° Celsius.

11. The splice system of claim 1 , wherein the heating cable comprises a conductor sized equal to or smaller than two American wire gauge.

12. The splice system of claim 1 , wherein the connector is a compression connector comprising a metal or semiconductive collar providing an electrical connection between the connector and a connector interface of the outer cold shrink tube.

13. The splice system of claim 1 , wherein the heating cable comprises an outer semiconductive layer and the outer cold shrink tube comprises:
a connector interface in contact with the connector;
a first stress cone in contact with the primary shim and the outer semiconductive layer of the first portion of the heating cable; and
a second stress cone in contact with the primary shim and the outer semiconductive layer of the second portion of the heating cable.

14. A splice for a skin-effect effect heating cable including an insulation layer and disposed in a heating tube, the splice comprising:
a primary cold shrink shim shrunk over a first length of the insulation layer of a first portion of the heating cable;
a secondary cold shrink shim shrunk over second length of the insulation layer of a second portion of the heating cable;
a connector electrically coupled to a conductor of the first portion of the heating cable and a conductor of the second portion of the heating cable; and
an outer cold shrink tube shrunk over the primary cold shrink shim, the secondary cold shrink shim, and the connector, and in electrical contact with a metallic pull box in electrical communication with the heating tube.

15. The splice of claim 14 , wherein the outer cold shrink tube comprises an outer semiconductive layer in electrical contact with an outer semiconductive layer of the heating cable.

16. The splice of claim 14 , wherein the connector is a shear bolt connector.

17. A method for installing a cold shrink splice on a skin effect heating cable, the method comprising:
removing an outer semiconductive layer along a first portion of the heating cable to expose a first length of an insulation layer of the heating cable;
installing a primary shim over at least a portion of the first length of the insulation layer;
removing the outer semiconductive layer along a second portion of the heating cable to expose a second length of the insulation layer of the heating cable;
installing a secondary shim over at least a portion of the second length of the insulation layer;
installing a cold shrink tube over the primary shim and the secondary shim; and
placing the cold shrink tube in electrical contact with a pull box.

18. The method of claim 17 and further comprising coupling the first portion of the heating cable to the second portion of the heating cable with a connector.

19. The method of claim 18 and further comprising:
arranging a connector interface of the cold shrink tube over the connector;
arranging a first stress cone of the cold shrink tube over the primary shim and the outer semiconductive layer; and
arranging a second stress cone of the cold shrink tube over the secondary shim and the outer semiconductive layer.

20. The method of claim 17 and further comprising greasing the portion of the first length of the insulation layer prior to installing the primary shim.

Assignees

• Nvent Services Gmbh

Inventors

• Iyer Ganpathy
• Becker Paul
• Parman David

Classifications

• H05B3/52

  Apparatus or processes for filling or compressing insulating material in tubes · CPC title

• H02G15/10

  protected by boxes, e.g. by distribution, connection or junction boxes · CPC title

• H05B3/08

  having electric connections specially adapted for high temperatures · CPC title

• H02G15/184 Primary

  with devices for relieving electrical stress · CPC title

• H02G15/182

  held in expanded condition in radial direction prior to installation · CPC title