Patent US3617319A successfully refreshed from Google Patents.
US3617319A
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Highly refractory aluminous cement and process for its manufacture
Assignee: LafargeHolcim Ciments SA
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Filing: 1968-07-24
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Granted: 1971-11-02
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Expires: 1988-07-24
Abstract
Abstract A highly refractory aluminous cement which comprises about 60% clinker, about 40% Al2O3, about 2% AlNa3F6 and about 0.18% to 2.5% sodium citrate and has a grain size distribution in which about 90% of the particles are under 30 microns. The clinker is formed by burning Al2O3 (98% purity) and CaCO3 (99% purity). It contains a mixture of CaO.Al2O3 and CaO.2Al2O3 in the ratio of approximately 1:1. The clinker is crushed, and the required amounts of A12O3, AlNa3F6 and sodium citrate are added. Final crushing reduces the size of the desired dimensions.
Inventors
- 👤 Gerard Henri Sadran
- 👤 Louise Marie Assaud
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 23:22
CPC Classifications
C; C04; C04B; C04B7/00; C04B7/36; C04B7/48; C04B7/52; C04B28/00; C04B28/02; C04B28/06; C04B7/32
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
178 words
A process for the preparation of a highly refractory aluminous cement which consists essentially of the steps of: a. clinkering a crude mix that consists essentially of sufficient amounts of Al2O3 having a purity of about 98 percent by weight and calcium carbonate having a purity of approximately 99 percent to form a clinker having an SiO2 content of below about 0.3 percent by weight, and having a Fe2O3 content below about 0.3 percent by weight, an Al2O3 content from about 69 to about 71 percent by weight, and a CaO content of from about 28 percent to about 30 percent by weight, said clinker having a ratio of CaO.Al2O3 to CaO.2Al2O3 which is substantially equal to 1; b. milling the clinker; c. adding to the milled clinker, Al2O3, AlNa3F6 and sodium citrate to form a mix containing Clinker-from 59.5 to 60.5% 40% Al2O3-from 38 to 40% AlNa3F6-from 1.5 to 2.5% Na citrate-from 0.18 to 2.5%; and d. milling the mix obtained thereby so that about 90 of the particles are smaller than about 30 microns in size.
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) | 1974-11-01 | 1975-05-03 | 1975-11-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-11-01 | 1979-05-03 | 1979-11-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-11-01 | 1983-05-03 | 1983-11-02 | $7700.00 | Window Closed / Lapsed |