Electrically insulating material and conductor wrap for electrical equipment, such as transformers

Patent metadata

Field	Value
Publication number	US-2016351291-A1
Application number	US-201515113963-A
Country	US
Kind code	A1
Filing date	Jan 27, 2015
Priority date	Jan 27, 2014
Publication date	Dec 1, 2016
Grant date	—

Abstract

An article comprises fully hydrolyzed polyvinyl alcohol fibers, an inorganic filler, and a polymer binder. The article can be formed as an electrically insulating saturated nonwoven sheet for electrical equipment, such as a liquid filled transformer, which can be substantially cellulose free.

First claim

What is claimed is:

1 . An article comprising:
fully hydrolyzed polyvinyl alcohol fibers; an inorganic filler; and a polymer binder.

2 . The article of claim 1 formed as a nonwoven sheet.

3 . The article of claim 1 wherein the inorganic filler comprises at least one of kaolin clay, talc, mica, calcium carbonate, silica, alumina, alumina trihydrate, montmorillonite, smectite, bentonite, illite, chlorite, sepiolite, attapulgite, halloysite, vermiculite, laponite, rectorite, perlite, aluminum nitride, silicon carbide, boron nitride, and combinations thereof.

4 . The article of claim 3 wherein inorganic filler comprises kaolin clay.

5 . The article of claim 4 wherein the kaolin clay comprises at least one of water-washed kaolin clay, delaminated kaolin clay, calcined kaolin clay, and surface-treated kaolin clay.

6 . The article of claim 1 , wherein the polymer binder comprises a latex-based material.

7 . The article of claim 1 , wherein the polymer binder comprises at least one of acrylic, nitrile, and styrene acrylic latex.

8 . The article of claim 1 , further comprising a binder fiber resistant to hot oil.

9 . The article of claim 9 , wherein the binder fiber comprises PPS fiber.

10 . The article of claim 1 comprising from about 20% to about 50% fully hydrolyzed polyvinyl alcohol fibers, wherein the percentages are by weight.

11 . The article of claim 10 , comprising:
from about 40% to about 60% kaolin clay; from about 5% to about 20% polymer binder; and from about 0% to about 20% PPS fiber, wherein the percentages are by weight.

12 . The article of claim 1 , wherein the article is substantially cellulose free.

13 . The article of claim 1 wherein the article is non-hygroscopic.

14 . Electrical equipment comprising conductor wrapped by the article of claim 1 .

15 . The electrical equipment of claim 14 comprising one of a transformer, a motor, and a generator.

16 . The electrical equipment of claim 15 comprising a liquid filled transformer.

17 . An oil filled transformer comprising an electrically insulating material comprising fully hydrolyzed polyvinyl alcohol fibers.

18 . The oil filled transformer of claim 17 , wherein the electrical insulating material further comprises an inorganic filler and a polymer binder.

19 . The oil filled transformer of claim 18 , wherein the electrical insulating material further comprises about 20% to about 50% fully hydrolyzed polyvinyl alcohol fibers, from about 40% to about 60% kaolin clay, from about 5% to about 20% polymer binder, and from about 0% to about 20% PPS fiber, wherein the percentages are by weight.

20 . The oil filled transformer of claim 17 , wherein the electrical insulating material is substantially cellulose free.

Assignees

• 3M Innovative Properties Co

Inventors

• Turpin Robert H
• Huang Mitchell T
• Stankes David S

Classifications

• C08L29/04

  Polyvinyl alcohol; Partially hydrolysed homopolymers or copolymers of esters of unsaturated alcohols with saturated carboxylic acids · CPC title

• H01B3/47

  fibre-reinforced plastics, e.g. glass-reinforced plastics · CPC title

• H01B3/301

  Macromolecular compounds obtained by reactions forming a linkage containing sulfur with or without nitrogen, oxygen or carbon in the main chain of the macromolecule, not provided for in group H01B3/302 · CPC title

• H01B3/448

  from other vinyl compounds · CPC title

• H01B3/447

  from acrylic compounds · CPC title