Patent US3718489A successfully refreshed from Google Patents.
US3718489A
Expired / Lapsed
US
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Insulating castable
Assignee: GREEN A REFRACTORIES CO
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Filing: 1971-01-04
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Granted: 1973-02-27
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Expires: 1991-01-04
Abstract
Abstract The disclosure concerns an insulating refractory castable useable at temperatures above 2,800*F., and specifically an insulating refractory castable useable at 3,000*F. which has a bulk density of from 82 to 88 pounds per cubic foot in place. The product comprises 60-70 percent of a size graded acid and/or alumina refractory aggregate, 5 to 15 percent expanded clay aggregate of a density of from 9-11 pounds per cubic foot, and from 15 to 35 percent calcium aluminate cement.
Inventors
- 👤 J Crookston
- 👤 G Charles
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 21:55
CPC Classifications
C; C04; C04B; C04B28/00; C04B28/02; C04B28/06
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
58 words
The castable of claim 1 wherein the aggregate includes raw kyanites, calcined fireclay and calcined alumina and the castable has a screen analysis of from about 0.5 to about 5 percent +10 mesh, about 38 to about 48.5 percent -10 +65 mesh, and about 51 to about 57 percent -65 mesh, said castable being usable at 3, 000*F.
Claim 2
Dependent Claim
47 words
The castable of claim 1 wherein the aggregate contains raw kyanites, calcined fireclay, and calcined alumina and the castable has a screen analysis of about 3 percent +10 mesh, about 40 percent -10 +65 mesh and about 57 percent -65 mesh, said castable being usable at 3000*F.
Claim 3
Dependent Claim
47 words
The castable of claim 1 wherein the aggregate includes raw kyanites, calcined fireclay, and calcined alumina and the castable has a screen analysis of about 1.5 percent +10 mesh, about 15 percent -10 +65 mesh and about 83.5 -65 mesh, said castable being usable at about 2,800*F.
Claim 4
Dependent Claim
35 words
The castable of claim 1 wherein the expanded clay has a size gradation of -4 +10 mesh of about 9 to about 15 percent and -10 +28 mesh of about 85 to about 91 percent.
Claim 5
Dependent Claim
51 words
The castable of claim 1 wherein the aggregate has a size gradation of +10 mesh, about 8 to about 14 percent -10 +28 mesh of about 53 to about 59 percent, -28 +65 mesh of about 20 to about 28 percent, and -65 mesh of about 7 to about 11 percent.
References Cited (Backward Citations)
US3341339A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-02-27 | 1976-08-28 | 1977-02-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-02-27 | 1980-08-28 | 1981-02-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-02-27 | 1984-08-28 | 1985-02-27 | $7700.00 | Window Closed / Lapsed |