US4957887A
Expired / Lapsed
US
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Magnesite-carbon refractories
Assignee: Resco Products Inc
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Filing: 1990-03-22
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Granted: 1990-09-18
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Expires: 2010-03-22
Abstract
Abstract A mix for forming a carbon-bonded refractory comprising from about 8 to 30 wt. % of a high purity carbon, about 0.1 to 1 wt. % of aluminum metal, magnesium metal, or a mixture thereof, and the balance a high purity magnesite, and for each 100 wt. % of said magnesite, carbon, and metal, a carbonaceous bonding agent in an amount sufficient to bond the mix; said carbon containing at least about 98% carbon and said magnesite containing at least about 98% MgO, and containing less than about 0.03% boron oxide, less than about 0.3% silica, and having a CaO/SiO 2 weight ratio above about 2, and the resultant carbon-bonded refractory shapes and liners for metal processing equipment, especially BOF, made from such shapes and the method of increasing the life of liners for such equipment.
Inventors
- 👤 David J. Michael
- 👤 David A. Kirk
- 👤 Leigh F. Brooks
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 05:51
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/66; C04B35/01; C04B35/013; C04B35/03; C04B35/04; C04B35/043
Claims Analysis
Total Claims: 37
Claim 1
Independent Claim
107 words
A mix for forming a magnesite-carbon refractory comprising from about 8 to 30 wt.% of a high purity carbon consisting of 0-4 wt.% carbon black and the balance graphite, about 0.1 to 1 wt.% of aluminum metal, magnesium metal, or a mixture thereof, and the balance a high purity magnesite, and a carbonaceous bonding agent in an amount sufficient to bond the mix; said magnesite containing at least about 98% MgO and containing less than about 0.03% boron oxide, less than about 0.3% silica, and having a CaO/SiO 2 weight ratio above about 2, and said graphite having a loss on ignition of at least about 98%.
Claim 2
Dependent Claim
107 words
A mix for forming a magnesite-carbon refractory comprising from about 8 to 30 wt.% of a high purity carbon consisting of 0-4 wt.% carbon black and the balance graphite, about 0.1 to 1 wt.% of aluminum metal, magnesium metal, or a mixture thereof, and the balance a high purity magnesite, and a carbonaceous bonding agent in an amount sufficient to bond the mix; said magnesite containing at least about 98% MgO and containing less than about 0.03% boron oxide, less than about 0.3% silica, and having a CaO/SiO 2 weight ratio above about 2, and said graphite having a loss on ignition of at least about 98%.
Claim 3
Dependent Claim
30 words
The mix of claim 1 wherein said magnesite contains at least 99% MgO and said carbonaceous bonding agent is a novolak resin, a resol resin, tar, pitch, or mixtures thereof.
Claim 4
Dependent Claim
16 words
The mix of claim 1 or 2 wherein said graphite is a flake or vein graphite.
Claim 5
Dependent Claim
63 words
The mix of claim 1 or 2 wherein said graphite is a flake or vein graphite having at least about 75% by weight -65 mesh or finer particles and a loss on ignition of at least about 99%, and said bonding agent is present in an amount of about 1.5 to 6 wt.% for each 100 wt.% of said magnesite, graphite, and metal.
Claim 6
Dependent Claim
148 words
A mix for forming a magnesite-carbon refractory consisting essentially of from about 8 to 30 wt.% of a high purity carbon consisting of 0 to 4 wt. % carbon black and the balance a flake or vein graphite, about 0.1 to 1 wt.% of aluminum metal, magnesium metal, or a mixture thereof, and the balance a high purity magnesite, and for each 100 wt.% of said magnesite, carbon, and metal, from about 1.5 to 6 wt.% of a carbonaceous bonding agent selected from novolak resins, resol resins, tar, pitch or mixtures thereof; said magnesite containing at least about 98% MgO and containing less than about 0.03% boron oxide, less than about 0.3% silica, and having a CaO/SiO 2 weight ratio above about 2, and said graphite having a loss on ignition of at least about 98% and at least about 75% by weight -65 mesh or finer particles
Claim 7
Dependent Claim
148 words
A mix for forming a magnesite-carbon refractory consisting essentially of from about 8 to 30 wt.% of a high purity carbon consisting of 0 to 4 wt. % carbon black and the balance a flake or vein graphite, about 0.1 to 1 wt.% of aluminum metal, magnesium metal, or a mixture thereof, and the balance a high purity magnesite, and for each 100 wt.% of said magnesite, carbon, and metal, from about 1.5 to 6 wt.% of a carbonaceous bonding agent selected from novolak resins, resol resins, tar, pitch or mixtures thereof; said magnesite containing at least about 98% MgO and containing less than about 0.03% boron oxide, less than about 0.3% silica, and having a CaO/SiO 2 weight ratio above about 2, and said graphite having a loss on ignition of at least about 98% and at least about 75% by weight -65 mesh or finer particles
Claim 8
Dependent Claim
10 words
The mix of claim 5, wherein the metal is aluminum.
Claim 9
Dependent Claim
10 words
The mix of claim 5, wherein the metal is magnesium.
Claim 10
Dependent Claim
15 words
The mix of claim 5 wherein, the metal is a mixture of aluminum and magnesium.
Claim 11
Dependent Claim
120 words
An unburned magnesite-carbon refractory shape consisting of a baked mix comprising, from about 8 to 30 wt.% of a high purity carbon consisting of 0-4 wt.% carbon black and the balance graphite, about 0.1 to 1 wt.% of aluminum metal, magnesium metal, or a mixture thereof, and the balance a high purity magnesite, and for each 100 wt.% of said magnesite, carbon, and metal, a carbonaceous bonding agent in an amount sufficient to bond the mix; said magnesite containing at least about 98% MgO and containing less than about 0.03% boron oxide, less than about 0.3% silica, and having a CaO/SiO 2 weight ratio above about 2, and said graphite having a loss on ignition of at least about 98%.
Claim 12
Dependent Claim
120 words
An unburned magnesite-carbon refractory shape consisting of a baked mix comprising, from about 8 to 30 wt.% of a high purity carbon consisting of 0-4 wt.% carbon black and the balance graphite, about 0.1 to 1 wt.% of aluminum metal, magnesium metal, or a mixture thereof, and the balance a high purity magnesite, and for each 100 wt.% of said magnesite, carbon, and metal, a carbonaceous bonding agent in an amount sufficient to bond the mix; said magnesite containing at least about 98% MgO and containing less than about 0.03% boron oxide, less than about 0.3% silica, and having a CaO/SiO 2 weight ratio above about 2, and said graphite having a loss on ignition of at least about 98%.
Claim 13
Dependent Claim
20 words
The refractory shape of claim 9 wherein said shape is a brick and said magnesite contains at least 99% MgO.
Claim 14
Dependent Claim
17 words
The refractory shape of claim 9 or 10 wherein said graphite is a flake or vein graphite.
Claim 15
Dependent Claim
47 words
The refractory shape of claim 9 or 10, wherein said carbonaceous bonding agent is a novolak resin, a resol resin, tar, pitch, or mixtures thereof and is present in an amount of about 1.5 to 6 wt.% for each 100 wt.% of said magnesite, graphite, and metal.
Claim 16
Dependent Claim
13 words
The refractory shape of claim 9 or 10 wherein the metal is aluminum.
Claim 17
Dependent Claim
13 words
The refractory shape of claim 9 or 10 wherein the metal is magnesium.
Claim 18
Dependent Claim
18 words
The refractory shape of claim 9 or 10 wherein the metal is a mixture of aluminum and magnesium.
Claim 19
Dependent Claim
132 words
An unburned refractory brick consisting essentially of a baked mix consisting essentially of from about 8 to 30 wt.% of a high purity carbon consisting of 0-4 wt.% carbon black and the balance graphite, about 0.1 to 1 wt.% of aluminum metal, magnesium metal, or mixtures thereof, and the balance a high purity magnesite, and for each 100 wt.% of said magnesite, carbon, and metal, from about 1.5 to 6 wt.% of a carbonaceous bonding agent; said magnesite containing at least about 98% MgO and containing less than about 0.03% boron oxide, less than about 0.3% silica and having a CaO/SiO 2 weight ratio above about 2, and said graphite having a loss on ignition of at least about 98% and at least about 75% by weight -65 mesh or finer particles.
Claim 20
Dependent Claim
132 words
An unburned refractory brick consisting essentially of a baked mix consisting essentially of from about 8 to 30 wt.% of a high purity carbon consisting of 0-4 wt.% carbon black and the balance graphite, about 0.1 to 1 wt.% of aluminum metal, magnesium metal, or mixtures thereof, and the balance a high purity magnesite, and for each 100 wt.% of said magnesite, carbon, and metal, from about 1.5 to 6 wt.% of a carbonaceous bonding agent; said magnesite containing at least about 98% MgO and containing less than about 0.03% boron oxide, less than about 0.3% silica and having a CaO/SiO 2 weight ratio above about 2, and said graphite having a loss on ignition of at least about 98% and at least about 75% by weight -65 mesh or finer particles.
Claim 21
Dependent Claim
24 words
The refractory brick of claim 16 wherein said carbonaceous bonding agent is a novolak resin, a resol resin, tar, pitch, or mixtures thereof. ,
Claim 22
Dependent Claim
17 words
The refractory brick of claim 16 or 17 wherein said graphite is a flake or vein graphite.
Claim 23
Dependent Claim
132 words
A refractory brick lining for metal processing equipment comprising a plurality of unburned magnesite-carbon brick, said brick consisting essentially of a baked mix comprising from about 8 to 30 wt.% of a high purity carbon consisting of 0-4 wt.% carbon black and the balance graphite, and about 0.1 to 1 wt.% aluminum metal, magnesium metal or mixtures thereof, and the balance a high purity magnesite, and for each 100 wt.% of said magnesite, carbon and metal a carbonaceous bonding agent in an amount sufficient to bond said mix; said magnesite containing at least about 98% MgO and containing less than about 0.03% boron oxide, less than about 0.3% silica, and having a CaO/SiO 2 weight ratio above about 2, and said graphite having a loss on ignition of at least about 98%.
Claim 24
Dependent Claim
132 words
A refractory brick lining for metal processing equipment comprising a plurality of unburned magnesite-carbon brick, said brick consisting essentially of a baked mix comprising from about 8 to 30 wt.% of a high purity carbon consisting of 0-4 wt.% carbon black and the balance graphite, and about 0.1 to 1 wt.% aluminum metal, magnesium metal or mixtures thereof, and the balance a high purity magnesite, and for each 100 wt.% of said magnesite, carbon and metal a carbonaceous bonding agent in an amount sufficient to bond said mix; said magnesite containing at least about 98% MgO and containing less than about 0.03% boron oxide, less than about 0.3% silica, and having a CaO/SiO 2 weight ratio above about 2, and said graphite having a loss on ignition of at least about 98%.
Claim 25
Dependent Claim
61 words
The refractory brick liner of claim 19 wherein the magnesite contains at least about 99% MgO, the carbon is a flake or vein graphite having at least about 75% by weight -65 mesh or finer particles, and said bonding agent is present in an amount of from about 1.5 to 6 wt.% for each 100 wt.% of magnesite, graphite, and metal.
Claim 26
Dependent Claim
26 words
The refractory brick liner of claim 19 or 20 wherein said carbonaceous bonding agent is a novolak resin, a resol resin, tar, pitch, or mixtures thereof.
Claim 27
Dependent Claim
14 words
The refractory brick liner of claim 19 or 20 wherein the metal is aluminum.
Claim 28
Dependent Claim
14 words
The refractory brick liner of claim 19 or 20 wherein the metal is magnesium.
Claim 29
Dependent Claim
19 words
The refractory brick liner of claim 19 or 20 wherein the metal is a mixture of aluminum and magnesium.
Claim 30
Independent Claim
150 words
The method of increasing the life of liners for metal processing equipment comprising forming a lining in said equipment comprising a plurality of unburned magnesite-carbon brick and subsequently burning said brick; said unburned brick consisting essentially of a baked mix comprising from about 8 to 30 wt.% of a high purity carbon consisting of 0-4 wt.% carbon black and the balance graphite, about 0.1 to 1 wt% of aluminum metal, magnesium metal, or a mixture thereof, and the balance a high purity magnesite, and for each 100 wt.% of said magnesite, graphite and metal, a carbonaceous bonding agent in an amount sufficient to bond the mix; said magnesite containing at least about 98% MgO and containing less than about 0.03% boron oxide, less than about 0.3% silica, and having a CaO/SiO 2 weight ratio above about 2, and said carbon having a loss of ignition of at least about 98%.
Claim 31
Independent Claim
150 words
The method of increasing the life of liners for metal processing equipment comprising forming a lining in said equipment comprising a plurality of unburned magnesite-carbon brick and subsequently burning said brick; said unburned brick consisting essentially of a baked mix comprising from about 8 to 30 wt.% of a high purity carbon consisting of 0-4 wt.% carbon black and the balance graphite, about 0.1 to 1 wt% of aluminum metal, magnesium metal, or a mixture thereof, and the balance a high purity magnesite, and for each 100 wt.% of said magnesite, graphite and metal, a carbonaceous bonding agent in an amount sufficient to bond the mix; said magnesite containing at least about 98% MgO and containing less than about 0.03% boron oxide, less than about 0.3% silica, and having a CaO/SiO 2 weight ratio above about 2, and said carbon having a loss of ignition of at least about 98%.
Claim 32
Dependent Claim
36 words
The method of claim 25 wherein the magnesite contains at least about 99% MgO and the graphite is a flake graphite or vein graphite having at least about 75% by weight -65 mesh or finer particles.
Claim 33
Dependent Claim
14 words
The method of claim 26 wherein the magnesite contains at least about 99% MgO.
Claim 34
Dependent Claim
47 words
The method of claim 25, 26, or 27 wherein said carbonaceous bonding agent is a novolak resin, a resol resin, tar, pitch, or mixtures thereof and is present in an amount of about 1.5 to 6 wt.% for each 100 wt.% of said magnesite, carbon, and metal.
Claim 35
Dependent Claim
13 words
The method of claim 25, 26, or 27 wherein the metal is aluminum.
Claim 36
Dependent Claim
13 words
The method of claim 25, 26, or 27 wherein the metal is magnesium.
Claim 37
Dependent Claim
18 words
The method of claim 25, 26, or 27 wherein the metal is a mixture of aluminum and magnesium.
References Cited (Backward Citations)
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