US4071588A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for production of magnetite spheres with an arc heater
Assignee: Westinghouse Electric Corp
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Filing: 1976-12-09
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Granted: 1978-01-31
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Expires: 1996-12-09
Abstract
Abstract A process for the production of magnetic spheres from grit of magnetite ore by introducing the grit into an arc heated gas jet, thus heating the grit to a temperature of at least 1600° C, and allowing the melted magnetite droplets to spheroidize and cool to a solid state.
Inventors
- 👤 Maurice G. Fey
- 👤 Charles B. Wolf
- 👤 Paul E. Martin
- 👤 II Francis J. Harvey
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 20:58
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/62; G11B5/68; G11B5/70; G11B5/706; G11B5/70626; G11B5/70642; G11B5/70678; G11B5/70684; G11B5/70689; C; C01; C01G; C01G49/00; C01G49/02; C01G49/08; C04; C04B; C04B35/00; C04B35/01; C04B35/26; C04B35/622; C04B35/653; C01P; C01P2004/00; C01P2004/30; C01P2004/32; C01P2004/60; C01P2004/61
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
115 words
A process for producing particulated magnetite spheres by thermal fusion of magnetite ore, comprising: a. striking an electric arc in an axial gap between generally hollow, cylindrical electrodes, said electrodes forming a chamber for said arc, b. causing the arc to rotate and form a substantially cylindrical arc path between the electrodes, c. directing gas through the gap into the arc chamber to thereby form an elongated arc heated gas jet, d. introducing particles of magnetite ore having a non-spherical shape with sufficient momentum into the arc heated gas jet to melt the particles to effect spheriodization by formation of droplets by surface tension, and e. cooling the droplets to solid state to preserve sphericity.
Claim 2
Dependent Claim
115 words
A process for producing particulated magnetite spheres by thermal fusion of magnetite ore, comprising: a. striking an electric arc in an axial gap between generally hollow, cylindrical electrodes, said electrodes forming a chamber for said arc, b. causing the arc to rotate and form a substantially cylindrical arc path between the electrodes, c. directing gas through the gap into the arc chamber to thereby form an elongated arc heated gas jet, d. introducing particles of magnetite ore having a non-spherical shape with sufficient momentum into the arc heated gas jet to melt the particles to effect spheriodization by formation of droplets by surface tension, and e. cooling the droplets to solid state to preserve sphericity.
Claim 3
Dependent Claim
20 words
The process of claim 1 in which the arc heated gas jet has a temperature of at least 1600° C.
Claim 4
Dependent Claim
23 words
The process of claim 1 in which the arc heated gas jet operates in an atmosphere that comprises from 5 to 21% oxygen.
Claim 5
Dependent Claim
19 words
The process of claim 1 in which the particles have a size of from about 44 to 149 microns.
Claim 6
Dependent Claim
22 words
The process of claim 1 in which the arc heated gas jet is operated at from about 150 to about 1500 kilowatts.
Claim 7
Dependent Claim
13 words
The process of claim 1 in which the droplets are cooled in air.
Claim 8
Dependent Claim
14 words
The process of claim 1 in which the droplets are cooled in water spray.
Claim 9
Dependent Claim
16 words
The process of claim 1 in which the droplets are cooled in a pool of water.
Claim 10
Dependent Claim
17 words
The process of claim 1 in which the droplets are cooled by radiation to the surrounding atmosphere.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-01-30 | 1981-08-01 | 1982-01-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-01-30 | 1985-08-01 | 1986-01-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-01-30 | 1989-08-01 | 1990-01-31 | $7700.00 | Window Closed / Lapsed |