US3275461A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Refractory
Assignee: Harbison Walker Refractories Co
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Filing: 1965-08-27
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Granted: 1966-09-27
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Expires: 1985-08-27
Abstract
No abstract record available.
Inventors
- 👤 Davies Ben
- 👤 Havranek Peter Harry
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 12:52
CPC Classifications
C; C21; C21C; C21C5/00; C21C5/28; C21C5/42; C21C5/44; C04; C04B; C04B35/00; C04B35/01; C04B35/03
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
141 words
THAT METHOD OF OBTAINING HIGH TEMPERATURE STRENGTH IN CERAMICALLY BONDED MAGNESIT REFRRACTORIES WITHOUT SACRIFICE OF HYDROCATION RESISTANT, CONSISTING ESSENTIALLY OF FABRICATING A REFRACTORY-BRICKMAKING SIZE GRADED BATCH OF DEAD BURNED DENSE MAGNESITE PPARTICLES, SAID MAGNESITE PARTICLES CHARACTERIZED BY INCLUDING AT LEAST SOME OF EACH OF THE CONSTITUENTS CAO, SIO2, B2O3, REMAINDER BEING R203 MATERIALS, THERE BEING, (A) UP TO ABOUT 1% SIO2 AND, (B) UP TO ABOUT 3% CAO, BY WEIGHT, (C) THE CAO:SIO2 WEIGHT RATIO BEING IN THE RANGE 2:1 TO LESS THAN 3:1, (D) (C+S)2/100 BEING THE MAXIMUM B2O3 PERCENTAGE CONTENT, WHEREIN C IS THE WEIGHT PERCENTAGE OF CAO AND S IS THE WEIGHT PERCENTAGE OF SIO2; (E) AT LEAST ABOUT 95 TO 99%, BY WEIGHT, OF SAID PARTICLES BEING MGO PLUS CAO, FORMING SAID BATCH INTO SHAPES, FIRING SAID SHAPES TO OBTAIN CERAMICALLY-BONDED, DENSE, HYDRATION RESISTANT, MAGNESIA REFRACTORY SHAPES.
Claim 2
Dependent Claim
141 words
THAT METHOD OF OBTAINING HIGH TEMPERATURE STRENGTH IN CERAMICALLY BONDED MAGNESIT REFRRACTORIES WITHOUT SACRIFICE OF HYDROCATION RESISTANT, CONSISTING ESSENTIALLY OF FABRICATING A REFRACTORY-BRICKMAKING SIZE GRADED BATCH OF DEAD BURNED DENSE MAGNESITE PPARTICLES, SAID MAGNESITE PARTICLES CHARACTERIZED BY INCLUDING AT LEAST SOME OF EACH OF THE CONSTITUENTS CAO, SIO2, B2O3, REMAINDER BEING R203 MATERIALS, THERE BEING, (A) UP TO ABOUT 1% SIO2 AND, (B) UP TO ABOUT 3% CAO, BY WEIGHT, (C) THE CAO:SIO2 WEIGHT RATIO BEING IN THE RANGE 2:1 TO LESS THAN 3:1, (D) (C+S)2/100 BEING THE MAXIMUM B2O3 PERCENTAGE CONTENT, WHEREIN C IS THE WEIGHT PERCENTAGE OF CAO AND S IS THE WEIGHT PERCENTAGE OF SIO2; (E) AT LEAST ABOUT 95 TO 99%, BY WEIGHT, OF SAID PARTICLES BEING MGO PLUS CAO, FORMING SAID BATCH INTO SHAPES, FIRING SAID SHAPES TO OBTAIN CERAMICALLY-BONDED, DENSE, HYDRATION RESISTANT, MAGNESIA REFRACTORY SHAPES.
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) | 1969-09-26 | 1970-03-28 | 1970-09-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-09-26 | 1974-03-28 | 1974-09-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-09-26 | 1978-03-28 | 1978-09-27 | $7700.00 | Window Closed / Lapsed |