IP Library Granted Patent US 8,361,351
Granted Patent B2
US 8,361,351 · App. 13/349,799 · Granted Jan 29, 2013

Additive for dielectric fluid

Inventors: Kevin J. Rapp (Oak Creek, WI); Jerry L. Corkran (Waukesha, WI); Gary A. Gauger (Franklin, WI); Charles Patrick McShane (Waukesha, WI)
Assignee: Cooper Industries, Inc.
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Quick Facts
Patent No.
US 8,361,351
App. No.
13/349,799
Granted
Jan 29, 2013
Kind
B2
Abstract

A dielectric fluid comprising hydrocarbon liquid admixed with an ester-based compound, wherein the ester-based compound is present in an effective amount to impart breakdown inhibiting properties to a paper insulation material when the dielectric fluid is in contact with the paper material.

Claims (10)

1. A transformer with a dielectric fluid therein, wherein the dielectric fluid comprises:

(a) 1% to 75% by weight of a methyl ester derived from esterification of a fatty acid, wherein the fatty acid is saturated or unsaturated; and

(b) 0.1% to 2.5% by weight of at least one additive selected from an antioxidant, an antimicrobial agent, and a pour point depressant; and

(c) the balance a petroleum derived mineral oil or a petroleum derived synthetic oil.

2. The transformer of claim 1 , wherein the fatty acid is selected from the group consisting of myristic, palmitic, stearic, oleic, linoleic, linoenic, arachidic, eicosenoic, behenic, erucic, palmitiolic, docosadienoic, lignoseric, tetracossenoic, margaric, margaroleic, gadoleic, caprylic, capric, lauric, pentadecanoic, arachidonic, heptadecanoic acids and combinations thereof.

3. The transformer of claim 1 , wherein the fatty acid has 4 to 12 carbon atoms.

4. The transformer of claim 3 , wherein the fatty acid is selected from the group consisting of caprylic, capric, and lauric, and combinations thereof.

5. The transformer of claim 1 , wherein the additive is an antioxidant.

6. The transformer of claim 1 , wherein the dielectric fluid comprises 5% to 50% by weight of the methyl ester.

7. The transformer of claim 1 , wherein the composition comprises 5% to 25% by weight of the methyl ester.

Assignments (1)
MERGER Recorded Jul 18, 2012
From: COOPER INDUSTRIES, INC.
To: COOPER INDUSTRIES, LLC
Reel/Frame 028576/0675 →
Continuity (4)
Continuation 12889097 · Sep 23, 2010
Continuation 12422864 · Apr 13, 2009
Continuation 10677635 · Oct 2, 2003
Related Publication 20120139679A1 · Jun 7, 2012