Patent US4236931A successfully refreshed from Google Patents.
US4236931A
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Gas-permeable refractory parts
Assignee: Societe Europeenne des Produits Refractaires SAS
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Filing: 1979-06-12
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Granted: 1980-12-02
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Expires: 1999-06-12
Abstract
Abstract The invention relates to gas-permeable parts comprised, by weight, of (A) 60 to 90% of granules of a grain size from 5 mm to 0.2 mm formed from a material selected among the group consisting of a chamotte containing at least 42% of Al 2 O 3 , mullite, fired gibbsite containing more than 90% Al 2 O hd 3, sintered or fused cast corundum containing more than 95% Al 2 O 3 , natural chromite, sintered MgO, zircon sand and stabilized zirconia, and (B) 10 to 40% of a bonding cement comprised a calcium aluminate, a material selected among SiO 2 , Al 2 O 3 and Cr 2 O 3 having a particle size between 100 A and 0.1 micron, and alumina having a particle size between 1 and 100 microns. These parts retain a high mechanical strength when heated between hydraulic setting and ceramization, and are useful for blowing a gas therethrough in order to stir molten steel and cast iron.
Inventors
- 👤 Jean-Pierre Kiehl
- 👤 Jean-Pierre Remi
- 👤 Jacques R. P. Schoennahl
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 13:49
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/01; C04B35/10; C04B35/101; C04B35/106; B; B22; B22D; B22D1/00; B22D1/002; B22D1/005; C04B28/00; C04B28/02; C04B28/06; C04B35/105
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
187 words
Gas-permeable parts having a permeability of from 50 to 600 Nanoperms and retaining a high mechanical strength when heated between their hydraulic setting temperature and their ceramization temperature, which parts are comprised by weight of: (A) 60 to 90% of granules of a grain size from 5 mm to 0.2 mm formed from a material selected among the group consisting of a chamotte containing at least 42% of Al 2 O 3 , mullite, fired gibbsite containing more than 90% Al 2 O 3 , sintered or fused cast corundum containing more than 95% Al 2 O 3 , natural chromite, sintered MgO, zircon sand and stabilized zirconia, bonded by (B) 10 to 40% of a cement or binder consisting by weight of: (a) 10 to 30% of a calcium aluminate, (b) 14 to 54% of a constituent having a particle size comprised between 100 A and 0.1 micron and selected from a material selected among the group consisting of silica, alumina and chromic oxide Cr 2 O 3 , and (c) 14 to 54% of alumina having a particle size comprised between 1 and 100 microns.
Claim 2
Dependent Claim
187 words
Gas-permeable parts having a permeability of from 50 to 600 Nanoperms and retaining a high mechanical strength when heated between their hydraulic setting temperature and their ceramization temperature, which parts are comprised by weight of: (A) 60 to 90% of granules of a grain size from 5 mm to 0.2 mm formed from a material selected among the group consisting of a chamotte containing at least 42% of Al 2 O 3 , mullite, fired gibbsite containing more than 90% Al 2 O 3 , sintered or fused cast corundum containing more than 95% Al 2 O 3 , natural chromite, sintered MgO, zircon sand and stabilized zirconia, bonded by (B) 10 to 40% of a cement or binder consisting by weight of: (a) 10 to 30% of a calcium aluminate, (b) 14 to 54% of a constituent having a particle size comprised between 100 A and 0.1 micron and selected from a material selected among the group consisting of silica, alumina and chromic oxide Cr 2 O 3 , and (c) 14 to 54% of alumina having a particle size comprised between 1 and 100 microns.
Claim 3
Dependent Claim
40 words
Gas-permeable parts as in claim 1, wherein the parts include 15 to 25% by weight of component (B) and wherein 75 to 85% by weight of the granules of component (A) have a grain size between 0.5 and 1.5 mm.
Claim 4
Dependent Claim
22 words
Gas-permeable parts as in claim 1, wherein the constituent (b) of the cement or binder (B) is Cr 2 O 3 .
Claim 5
Dependent Claim
36 words
Gas-permeable parts as in claim 1, which have a compressive strength higher than 200 kg/cm 2 between ambient temperature and 400° C., and which remains higher than 150 kg/cm 2 at temperatures up to 1400° C.
Claim 6
Dependent Claim
16 words
Gas-permeable parts as in claim 1 wherein said parts are in the form of truncated cones.
References Cited (Backward Citations)
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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) | 1983-12-02 | 1984-06-02 | 1984-12-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-12-02 | 1988-06-02 | 1988-12-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-12-02 | 1992-06-02 | 1992-12-02 | $7700.00 | Window Closed / Lapsed |