US4487804A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Coating to prevent the oxidation of electrodes during electric furnace steel making
Assignee: Minteq International Inc
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Filing: 1982-08-02
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Granted: 1984-12-11
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Expires: 2002-08-02
Abstract
Abstract A coating is provided which substantially lengthens the life of carbon and graphite electrodes used in electrical arc processes for the manufacture of ferrous metals. The coating forms a silica-phosphorus glass upon the electrodes.
Inventors
- 👤 Frederick V. Reven
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 20:00
CPC Classifications
C; C04; C04B; C04B41/00; C04B41/009; C03; C03C; C03C8/00; C03C8/02; C03C8/08; C03C8/14; C04B41/45; C04B41/50; C04B41/5053; C04B41/5057; C04B41/80; C04B41/81; C04B41/85; C04B41/87; H; H05; H05B; H05B7/00; H05B7/02; H05B7/06; H05B7/08; H05B7/085; Y; Y10; Y10T; Y10T428/00; Y10T428/25; Y10T428/259; Y10T428/26; Y10T428/263; Y10T428/30
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
28 words
An electrically conductive consumable carbon and/or graphite electrode having an impermeable coating of less than 1/4" thickness of a non-electrically conducting crystallized devitrifyable silica-phosphate glass containing titanium dioxide.
Claim 2
Dependent Claim
28 words
An electrically conductive consumable carbon and/or graphite electrode having an impermeable coating of less than 1/4" thickness of a non-electrically conducting crystallized devitrifyable silica-phosphate glass containing titanium dioxide.
Claim 3
Dependent Claim
86 words
An electricaly conductive consumable electrode from the group consisting of carbon and graphite electrodes, having coated thereon an impermeable layer of less than 1/4" of a composition that, when dried, is a non-electrically conducting crystallized devitrifyable silica phosphate glass, said composition prior to being applied to the electrode comprising in percentages by weight: 10-70% water; 0.5-15% finely divided silicon dioxide having a particle size less than 200 mesh; 1-25% phosphoric acid; 2-50% titanium dioxide having a particle size of less than 375 mesh; 2-50% silicon carbide.
Claim 4
Dependent Claim
86 words
An electricaly conductive consumable electrode from the group consisting of carbon and graphite electrodes, having coated thereon an impermeable layer of less than 1/4" of a composition that, when dried, is a non-electrically conducting crystallized devitrifyable silica phosphate glass, said composition prior to being applied to the electrode comprising in percentages by weight: 10-70% water; 0.5-15% finely divided silicon dioxide having a particle size less than 200 mesh; 1-25% phosphoric acid; 2-50% titanium dioxide having a particle size of less than 375 mesh; 2-50% silicon carbide.
Claim 5
Dependent Claim
49 words
The electrode of claim 2 having been coated with a composition comprising in percentages by weight: 15-60% water; 1-10% finely divided silicon dioxide having a particle size less than 200 mesh; 2-18% phosphoric acid; 3-35% titanium dioxide having a particle size of less than 375 mesh; 3-35% silicon carbide.
Claim 6
Dependent Claim
49 words
The electrode of claim 2 having been coated with a composition comprising in percentages by weight: 20-50% water; 1.5-7.5% finely divided silicon dioxide having a particle size less than 200 mesh; 4.5-15% phosphoric acid; 10-30% titanium dioxide having a particle size of less than 375 mesh; 10-30% silicon carbide.
Claim 7
Dependent Claim
91 words
An electrically conductive electrode from the group consisting of carbon and graphite electrodes, having coated thereon an impermeable layer of less than 1/4" of a composition that, when dried, is a non-electrically conducting crystallized devitrifyable silica phosphate glass, said composition prior to application to the electrode comprising in percentages by weight: 10-70% water; 0.5-15% finely divided silicon dioxide having a particle size less than 200 mesh; 1-25% phosphoric acid; 2-50% titanium dioxide having a particle size of less than 375 mesh; 2-50% silicon carbide; 0.05-7.5% sodium hexameta phosphate; 0.01-5.0% organic thickener.
Claim 8
Dependent Claim
91 words
An electrically conductive electrode from the group consisting of carbon and graphite electrodes, having coated thereon an impermeable layer of less than 1/4" of a composition that, when dried, is a non-electrically conducting crystallized devitrifyable silica phosphate glass, said composition prior to application to the electrode comprising in percentages by weight: 10-70% water; 0.5-15% finely divided silicon dioxide having a particle size less than 200 mesh; 1-25% phosphoric acid; 2-50% titanium dioxide having a particle size of less than 375 mesh; 2-50% silicon carbide; 0.05-7.5% sodium hexameta phosphate; 0.01-5.0% organic thickener.
Claim 9
Dependent Claim
52 words
The electrode of claim 5 having been coated with a composition comprising: 15-60% water; 1-10% finely divided silicon dioxide having a particle size less than 200 mesh; 2-18% phosphoric acid; 3-35% titanium dioxide having a particle size of less than 375 mesh; 3-35% silicon carbide; 0.1-7% sodium hexameta phosphate; 0.05-2.0% organic thickener.
Claim 10
Dependent Claim
52 words
The electrode of claim 5 having been coated with a composition comprising: 20-50% water; 1.5-7.5% finely divided silicon dioxide having a particle size less than 200 mesh; 4.5-15% phosphoric acid; 10-30% titanium dioxide having a particle size of less than 375 mesh; 10-30% silicon carbide; 0.25-5% sodium hexameta phosphate; 0.1-1.0% organic thickener.
Claim 11
Independent Claim
97 words
A method of protecting carbon and graphite electrodes used in the production of ferrous metals in electrical arc furnaces from oxidation during use which comprises coating said electrodes prior to their use with a composition comprising in percentages by weight: 1- 70% water; 0.5-15% finely divided silicon dioxide having a particle size less than 200 mesh; 1-25% phosphoric acid; 2-50% titanium dioxide having a particle size of less than 375 mesh; 2-50% silicon carbide; 0.05-7.5% sodium hexameta phosphate; 0.1-5.0% organic thickener; whereby the composition forms a crystallized devitrifyable silica-phosphate glass protecting the electrode from oxidation during use.
Claim 12
Independent Claim
97 words
A method of protecting carbon and graphite electrodes used in the production of ferrous metals in electrical arc furnaces from oxidation during use which comprises coating said electrodes prior to their use with a composition comprising in percentages by weight: 1- 70% water; 0.5-15% finely divided silicon dioxide having a particle size less than 200 mesh; 1-25% phosphoric acid; 2-50% titanium dioxide having a particle size of less than 375 mesh; 2-50% silicon carbide; 0.05-7.5% sodium hexameta phosphate; 0.1-5.0% organic thickener; whereby the composition forms a crystallized devitrifyable silica-phosphate glass protecting the electrode from oxidation during use.
Claim 13
Dependent Claim
49 words
The method of claim 8 wherein the composition comprises: 15-60% water; 1-10% finely divided silicon dioxide having a particle size less than 200 mesh; 2-18% phosphoric acid; 3-35% titanium dioxide having a particle size of less than 375 mesh; 3-35% silicon carbide; 0.1-7% sodium hexameta phosphate; 0.05-2.0% organic thickener.
Claim 14
Dependent Claim
49 words
The method of claim 8 wherein the composition comprises: 20-50% water; 1.5-7.5% finely divided silicon dioxide having a particle size less than 200 mesh; 4.5-15% phosphoric acid; 10-30% titanium dioxide having a particle size of less than 375 mesh; 10-30% silicon carbide; 0.25-5.0% sodium hexameta phosphate; 0.1-1.0% organic thickener.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-12-11 | 1988-06-11 | 1988-12-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-12-11 | 1992-06-11 | 1992-12-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-12-11 | 1996-06-11 | 1996-12-11 | $7700.00 | Window Closed / Lapsed |