US3753746A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Permeable refractory products
Assignee: Individual
•
Filing: 1971-01-15
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Granted: 1973-08-21
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Expires: 1991-01-15
Abstract
Abstract A porous refractory body, primarily a porous plug for the refractory lining of a vessel containing molten metal through which plug gas can be blown into the metal. This body has a cold crushing strength of not less than 200 kg/cm2 and consists of a coarse-grained refractory material with a minimum quantity of a suitable binding agent, and has permeable pores of a cross section not less than 0.05 mm and a gas permeability of at least 100, and preferably more than 500 nanoperm. The hot bending strength or modulus of rupture of the body at 1,400* C is from 20 - 60 kg/cm2. The refractory material is mixed with the binding agent, and the mixture is compressed with a pressure of at least 300 kg/cm2 before firing to bring substantially all of the grains into contact with adjacent grains.
Inventors
- 👤 O Koerner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 08:26
CPC Classifications
C; C21; C21C; C21C7/00; C21C7/04; B; B22; B22D; B22D1/00; B22D1/002; B22D1/005; C04; C04B; C04B38/00; C04B38/0051; C04B2111/00; C04B2111/00241; C04B2111/00405; C04B2111/00474; C04B2111/0087; C04B2201/00; C04B2201/40
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
57 words
A method according to claim 1 including the step of compressing the mixture by applying pressure such as to produce a refractory body having permeable pores with an average pore size of about 0.1 to 0.2 mm and a volume of about 10 percent to 15 percent of the body volume as measured by the Washburn method.
Claim 2
Dependent Claim
21 words
A method according to claim 1 wherein the granular material is selected from the group consisting of mullite, magnesia and corundum.
Claim 3
Dependent Claim
21 words
A method according to claim 1 wherein the binder includes a material selected from the group consisting of alumina and magnesia.
Claim 4
Dependent Claim
45 words
A method according to claim 1 wherein the granular material is selected from the group consisting of mullite and corundum, the binder is a material comprising aluminum oxide, and the bond-activating agent is selected from the group consisting of monoaluminum phosphate and chromium aluminum phosphate.
Claim 5
Dependent Claim
35 words
A method according to claim 1 wherein the granular material and binder comprise magnesia, the bond-activating agent is selected from the group consisting of chrome ore, the sesquioxides; chrome salts, chromic acid and boric acid.
Claim 6
Dependent Claim
191 words
A porous refractory body comprising at least about 90 percent by weight of a granular refractory material selected from the group consisting of oxide-containing neutral and oxide-containing basic refractory materials, at least about 85 percent by weight of the granular material having grain size greater than about one-half millimeter, substantially all of the grains being in physical contact with, and supported by, the surfaces of adjacent grains, and a sintered binding agent joining the adjacent grains of the body at their areas of contact and providing permeable pores therein having an average size of at least About 0.05 millimeter and a total volume of not less than about 10 percent of the body volume as measured by the Washburn method, at least about 30 percent of the binder agent comprising the same oxide mainly constituting the granular refractory material, whereby the body has a modulus of rupture of at least 20 kg/cm2 at 1,400* C, a cold crushing strength of at least 200 kg/cm2 and a permeability of at least 100 nanoperm. 8. A porous refractory body according to claim 7 comprising a plurality of successive layers having increasing particle size.
Claim 7
Dependent Claim
18 words
A porous refractory body according to claim 7 having a gas permeability of at least about 500 nanoperm.
Claim 8
Dependent Claim
37 words
A porous refractory body according to claim 7 wherein the granular refractory material is selected from the group consisting of mullite and corundum and the binding agent comprising refractory clay containing at least about 43 percent Al2O3.
References Cited (Backward Citations)
CA714478A
Cited
US2007052A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-08-20 | 1977-02-19 | 1977-08-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-08-20 | 1981-02-19 | 1981-08-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-08-20 | 1985-02-19 | 1985-08-21 | $7700.00 | Window Closed / Lapsed |