US4473654A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Low temperature bonding of refractory aggregates and refractory products of improved cold strength
Assignee: Baker J E Co
•
Filing: 1983-08-18
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Granted: 1984-09-25
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Expires: 2003-08-18
Abstract
Abstract Satisfactory bonding of refractory aggregate is obtained by providing the aggregate with at least 5.0% by weight of free CaO of minus 200 mesh (Tyler Standard Sieve) particle size, adding a small amount of a lithium compound to the aggregate and heating to a temperature of about 450° C. The modulus of rupture at room temperature of a brick made from dead burnt dolomite aggregate containing a fine fraction providing the finely divided CaO and the lithium compound additive and fired to 450° C. is well above 400 psi and may be substantially equivalent to that of a brick made of the same aggregate without the lithium compound additive and fired to 1200° C. The invention comprises the method of increasing the low temperature bonding strength of refractory aggregates, the unfired mixtures of the refractory aggregate containing the requisite CaO and the lithium compound with or without temporary liquid or solid binding agents, and the fired products made therefrom.
Inventors
- 👤 James W. Stendera
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 16:57
CPC Classifications
C; C04; C04B; C04B37/00; C04B35/00; C04B35/622; C04B35/626; C04B35/63; C04B35/632; C04B35/634; C04B35/01; C04B35/03; C04B35/04; C04B35/043; C04B35/06; C04B35/66; C04B2103/00; C04B2103/0004; C04B2103/0006; C04B2103/0008; C04B2111/00; C04B2111/00034; C04B2111/00146; C04B2111/00155; C04B2235/00; C04B2235/02; C04B2235/30; C04B2235/32; C04B2235/3205
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
106 words
A method for improving the low temperature bonding of refractory products comprising dry mixing a refractory aggregate comprising at least about 5% free CaO of less than 200 mesh size (Tyler Standard Sieve) with from about 0.1 to 5.0% by weight, based on the weight of the aggregate, of a finely divided solid lithium compound which does not decompose with evolution of water or other detrimental decomposition products upon heating, optionally adding a temporary non-aqueous binder to the mixture, emplacing, shaping and/or compacting the mixture and heating the emplaced, shaped and/or compacted mixture at a temperature in the range of from 400° C. to 1200° C.
Claim 2
Independent Claim
106 words
A method for improving the low temperature bonding of refractory products comprising dry mixing a refractory aggregate comprising at least about 5% free CaO of less than 200 mesh size (Tyler Standard Sieve) with from about 0.1 to 5.0% by weight, based on the weight of the aggregate, of a finely divided solid lithium compound which does not decompose with evolution of water or other detrimental decomposition products upon heating, optionally adding a temporary non-aqueous binder to the mixture, emplacing, shaping and/or compacting the mixture and heating the emplaced, shaped and/or compacted mixture at a temperature in the range of from 400° C. to 1200° C.
Claim 3
Dependent Claim
18 words
The method of claim 1 wherein the amount of lithium compound is less than about 1.0% by weight.
Claim 4
Dependent Claim
25 words
The method of claim 1 wherein the lithium compound is selected from the group consisting of lithium fluoride, lithium chloride, lithium nitrate and lithium carbonate.
Claim 5
Dependent Claim
12 words
The method of claim 1 wherein the lithium compound is lithium fluoride.
Claim 6
Dependent Claim
38 words
The method of claim 1 wherein the refractory aggregate is one which is suitable for use in ramming, castable, vibratable, plastic, mortar or gunning mixes, or for use in the production of refractory bricks or other refactory shapes.
Claim 7
Dependent Claim
30 words
The method of claim 1 wherein the refractory aggregate is a refractory brick making mixture, a non-aqueous liquid binder is used and the mixture is pressed into shapes before firing.
Claim 8
Dependent Claim
19 words
The method of claim 1 wherein refractory aggregate is a vibratable mixture, and the mixture is compacted by vibration.
Claim 9
Dependent Claim
27 words
The method of claim 1 wherein the refractory aggregate is an aggregate suitable for gunning mixtures and the mixture is emplaced by gunning techniques prior to heating.
Claim 10
Dependent Claim
28 words
The method of claim 1 wherein the refractory aggregate is an aggregate suitable for ramming and the mixture is emplaced and compacted by ramming technique prior to heating.
Claim 11
Dependent Claim
74 words
An unfired refractory composition having low temperature bonding properties comprising a refractory aggregate containing at least about 5% by weight free CaO of less than 200 mesh (Tyler Standard sieve) particle size and having from about 0.1 to 5.0% by weight, based on the total weight of the aggregate, of a finely divided solid lithium compound which does not decompose with evolution of water or other detrimental decomposition products upon heating dry mixed therewith.
Claim 12
Dependent Claim
74 words
An unfired refractory composition having low temperature bonding properties comprising a refractory aggregate containing at least about 5% by weight free CaO of less than 200 mesh (Tyler Standard sieve) particle size and having from about 0.1 to 5.0% by weight, based on the total weight of the aggregate, of a finely divided solid lithium compound which does not decompose with evolution of water or other detrimental decomposition products upon heating dry mixed therewith.
Claim 13
Dependent Claim
19 words
The composition of claim 10 wherein the amount of the lithium compound is less than about 1.0% by weight.
Claim 14
Dependent Claim
25 words
The composition of claim 10 wherein the lithium compound is selected from the group consisting of lithium fluoride, lithium chloride, lithium nitrate and lithium carbonate.
Claim 15
Dependent Claim
12 words
The composition of claim 10 wherein the lithium compound is lithium fluoride.
Claim 16
Dependent Claim
25 words
The composition of claim 10 wherein the refractory aggregate comprises dead burnt dolomite and the CaO is present in a fine fraction of said dolomite.
Claim 17
Dependent Claim
26 words
The composition of claim 10 wherein the refractory aggregate consists of dead burnt dolomite and the CaO is present in a fine fraction of said dolomite.
Claim 18
Dependent Claim
38 words
The composition of claim 14 wherein part of the refractory aggregate is dead burnt magnesia, the dead burnt magnesia providing a coarse fraction of the aggregate and the dead burnt dolomite providing a fine fraction of the aggregate.
Claim 19
Dependent Claim
21 words
The composition of any one of claims 10, 15, or 16 wherein the aggregate is one suitable for refractory brick making.
Claim 20
Dependent Claim
20 words
The composition of claim 10 additionally containing from about 1 to 10% by weight of a non-aqueous liquid temporary binder.
Claim 21
Dependent Claim
20 words
The composition of claim 10 additionally containing from about 1 to 10% by weight of a thermoplastic solid resinous binder.
Claim 22
Dependent Claim
20 words
The composition of claim 10 wherein the aggregate is suitable for refractory ramming, castable, vibratable, plastic, mortar or gunning mixtures.
Claim 23
Dependent Claim
18 words
An unfired, emplaced, shaped and/or compacted refractory composition as defined in any one of claims 10 to 16.
Claim 24
Dependent Claim
49 words
A fired refractory shape comprising the composition as defined in any one of claims 10 to 16, said shape having been fired at a temperature in the range of from about 400° to 1200° C. and having a modulus of rupture at room temperature in excess of 400 psi.
Claim 25
Dependent Claim
23 words
A fired refractory shape as defined in claim 22 wherein the modulus of rupture at room temperature is in excess of 1000 psi.
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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) | 1987-09-25 | 1988-03-26 | 1988-09-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-09-25 | 1992-03-26 | 1992-09-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-09-25 | 1996-03-26 | 1996-09-25 | $7700.00 | Window Closed / Lapsed |