Process for manufacturing a power cable and power cable obtainable thereof

Patent metadata

Field	Value
Publication number	US-10529469-B2
Application number	US-201615780998-A
Country	US
Kind code	B2
Filing date	Dec 9, 2016
Priority date	Dec 18, 2015
Publication date	Jan 7, 2020
Grant date	Jan 7, 2020

Abstract

The present invention relates to a process for manufacturing a power cable, which power cable comprises at least one core comprising a conductor and an expanded and crosslinked insulation layer surrounding said conductor, wherein said process comprises the steps a) to d): a) providing a blend of: a polymer composition comprising a polyolefin material, which polyolefin material bears silane moieties; a catalyst and a foaming system, wherein the provided blend will comprise at least 0.1% by weight of a foaming agent, with respect to the total weight of the polyolefin material; b) extruding a blend, as described in step a), on the conductor to form an insulation layer; c) foaming the insulation layer; and d) crosslinking the insulation layer; a power cable which is obtainable by the process, and use of the power cable.

First claim

The invention claimed is:

1. Process for manufacturing a power cable, which power cable comprises at least one core comprising a conductor and an expanded and crosslinked insulation layer surrounding said conductor, wherein said process comprises steps a) to d):
a) providing a blend of:
a polymer composition comprising a polyolefin material, which polyolefin material bears silane moieties,
a catalyst and
a foaming system, wherein the provided blend will comprise at least 0.1% by weight of a foaming agent, with respect to a total weight of the polyolefin material;
b) extruding the blend, as described in step a), on the conductor to form an insulation layer;
c) foaming the insulation layer; and
d) crosslinking the insulation layer.

2. The process according to claim 1 , wherein the foaming system comprises 0.1 to 0.7% by weight of the foaming agent.

3. The process according to claim 1 , wherein the polymer material comprises a low density polyethylene with hydrolysable silane groups.

4. The process according to claim 1 , wherein the polyolefin material comprises 0.001 to 15% by weight of silane compound.

5. A power cable which is defined as in, and is obtainable by the process according to claim 1 .

6. The power cable according to claim 5 , wherein the insulation layer has an expansion degree of 3 to 40%.

7. The power cable according to claim 5 , wherein the insulation layer is in contact with the conductor.

8. The power cable according to claim 5 , which is a low voltage cable or a medium voltage cable.

9. The power cable according to claim 5 , which comprises three cores each comprising a conductor.

10. The power cable according to claim 5 , wherein the insulation layer has an expansion degree of from 5% to 30%.

11. The power cable according to claim 5 , wherein the insulation layer has an expansion degree of from 5% to 25%.

12. The power cable according to claim 5 , wherein the insulation layer has an average cell size equal to or lower than 150 μm.

13. The power cable according to claim 5 , wherein the insulation layer has an average cell size equal to or lower than 100 μm.

Assignees

• Borealis Ag

Inventors

• Wannerskog Asa
• Galante Francisco
• Walter Peter
• Fagrell Ola

Classifications

• H01B13/14

  by extrusion {(extrusion in general B29C48/00)} · CPC title

• C08L23/26

  modified by chemical after-treatment (saponified copolymers C08L23/0861; unsaturated acid salts C08L23/0876) · CPC title

• C08J9/10

  developing nitrogen {, the blowing agent being a compound containing a nitrogen-to-nitrogen bond} · CPC title

• C08J9/06

  by a chemical blowing agent · CPC title

• H01B13/148

  Selection of the insulating material therefor · CPC title