Silicone multilayer insulation for electric cable

Patent metadata

Field	Value
Publication number	US-10134505-B2
Application number	US-201615159434-A
Country	US
Kind code	B2
Filing date	May 19, 2016
Priority date	Sep 25, 2012
Publication date	Nov 20, 2018
Grant date	Nov 20, 2018

Abstract

A cable has at least one elongated electric conductor and a multilayer insulation surrounding the electric conductor. The multilayer insulation has a first semiconducting layer and an electrically insulating layer. The two layers are made from a silicone rubber based composition. A method for making this cable includes co-extruding the first semiconducting layer and the electrically insulating layer.

First claim

The invention claimed is:

1. Process for manufacturing an electric cable,
the electric cable has at least one elongated electric conductor; and
a multilayer insulation surrounding said electric conductor,
wherein said multilayer insulation having a first semiconducting layer and an electrically insulating layer, said two layers being made from a silicone rubber based composition,
said method comprising the step of;
co-extruding the first semiconducting layer and the electrically insulating layer, wherein the composition used to obtain the first semi-conducting layer further comprises carbon rovings as conductive filler.

2. Process according to claim 1 , wherein the multilayer insulation has a second semiconducting layer made from a silicone rubber based composition, to form a 3-layer insulation, so that the first semiconducting layer, the electrically insulating layer and the second semiconducting layer are co-extruded layers.

3. Process according to claim 2 , wherein the first semiconducting layer is surrounded by the electrically insulating layer, and the electrically insulating layer is surrounded by the second semiconducting layer.

4. Process according to claim 1 , wherein at least one of the layers of said multilayer insulation is a crosslinked layer.

5. Process according to claim 1 , wherein the multilayer insulation is surrounded by a metal shield.

6. Process according to claim 1 , wherein the electric cable is a power cable supporting a voltage level of at least 5 kV.

7. Process according to claim 1 , wherein the layers of the multilayer insulation are extruded simultaneously.

8. Process according to claim 1 , wherein the co-extrusion is done with the same extrusion head.

9. Process according to claim 4 , wherein the layers of said multilayer insulation are crosslinked layers.

10. Process for manufacturing an electric cable, the electric cable has at least one elongated electric conductor; and a multilayer insulation surrounding said electric conductor, wherein said multilayer insulation having a first semiconducting layer and an electrically insulating layer, said two layers being made from a silicone rubber based composition, said method comprising the step of;
co-extruding the first semiconducting layer and the electrically insulating layer, so that the presence of gas and/or the presence of space between the extruded layers are substantially removed,
wherein the composition used to obtain the first semi-conducting layer further comprises carbon rovings as conductive filler.

Assignees

• Nexans

Inventors

• Gasser Markus
• Haner Franz
• Romann Luc

Classifications

• B29K2995/0005

  Conductive · CPC title

• B29C48/3366

  using a die with concentric parts, e.g. rings, cylinders · CPC title

• B32B25/20

  comprising silicone rubber · CPC title

• H01B13/141

  of two or more insulating layers · CPC title

• B29K2083/00

  Use of polymers having silicon, with or without sulfur, nitrogen, oxygen, or carbon only, in the main chain, as moulding material · CPC title