US4898368A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Wear resistant metallurgical tuyere
Assignee: Praxair Technology Inc
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Filing: 1988-08-26
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Granted: 1990-02-06
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Expires: 2008-08-26
Abstract
Abstract A tuyere having improved wear resistance at the tip, and a refractory walled metallurgical vessel incorporating the tuyere, characterized by an oxide thermal barrier coating on the outer surface of the outermost conduit of the tuyere having a thermal conductivity less than that of the refractory.
Inventors
- 👤 Paul J. Schaffer
- 👤 Robert C. Tucker, Jr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 19:04
CPC Classifications
C; C21; C21B; C21B7/00; C21B7/16; C21C; C21C5/00; C21C5/28; C21C5/30; C21C5/34; C21C5/42; C21C5/46; C21C5/48
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
51 words
A coaxial tuyere for use in a refractory walled metallurgical vessel, said tuyere comprising a central conduit and at least one conduit outer and coaxial thereto, each of said conduits having an outer surface and further comprising an oxide thermal barrier coating on the outer surface of the outermost coaxial conduit.
Claim 2
Dependent Claim
51 words
A coaxial tuyere for use in a refractory walled metallurgical vessel, said tuyere comprising a central conduit and at least one conduit outer and coaxial thereto, each of said conduits having an outer surface and further comprising an oxide thermal barrier coating on the outer surface of the outermost coaxial conduit.
Claim 3
Dependent Claim
23 words
The tuyere of claim 1 wherein the oxide thermal barrier coating has a thickness within the range of from 0.005 to 0.200 inch.
Claim 4
Dependent Claim
35 words
The tuyere of claim 1 wherein the oxide thermal barrier coating is from the group consisting of zirconia, partially stabilized zirconia, fully stabilized zirconia, hafnia, titania, silica, magnesia, alumina, chromia, mixtures thereof, and compounds thereof.
Claim 5
Dependent Claim
23 words
The tuyere of claim 1 further comprising a metallic undercoating between the outer surface of said conduit and the oxide thermal barrier coating.
Claim 6
Dependent Claim
29 words
The tuyere of claim 4 wherein between the metallic undercoating and the oxide thermal barrier coating there is at least one layer of a mixture of metal and oxide.
Claim 7
Dependent Claim
81 words
A metallurgical vessel comprising at least one refractory wall and having at least one coaxial tuyere passing through said wall for passage of fluid into the vessel, said tuyere comprising a central conduit and at least one conduit outer and coaxial thereto, each of said conduits having an outer surface and further comprising an oxide thermal barrier coating on the outer surface of the outermost coaxial conduit, said thermal barrier coating having a thermal conductivity less than that of said refractory.
Claim 8
Dependent Claim
81 words
A metallurgical vessel comprising at least one refractory wall and having at least one coaxial tuyere passing through said wall for passage of fluid into the vessel, said tuyere comprising a central conduit and at least one conduit outer and coaxial thereto, each of said conduits having an outer surface and further comprising an oxide thermal barrier coating on the outer surface of the outermost coaxial conduit, said thermal barrier coating having a thermal conductivity less than that of said refractory.
Claim 9
Dependent Claim
26 words
The vessel of claim 6 wherein the thermal conductivity of the oxide thermal barrier coating is not more than 50 percent of that of the refractory.
Claim 10
Dependent Claim
23 words
The vessel of claim 6 wherein the oxide thermal barrier coating has a thickness within the range of from 0.005 to 0.200 inch.
Claim 11
Dependent Claim
33 words
The vessel of claim 1 wherein the oxide thermal barrier coating forms a contiguous boundary in contact with the refractory through which the tuyere passes for a portion of their common adjacent area.
Claim 12
Dependent Claim
35 words
The vessel of claim 1 wherein the oxide thermal barrier coating is from the group consisting of zirconia, partially stabilized zirconia, fully stabilized zirconia, hafnia, titania, silica, magnesia, alumina, chromia, mixtures thereof, and compounds thereof.
Claim 13
Dependent Claim
23 words
The vessel of claim 6 further comprising a metallic undercoating between the outer surface of said conduit and the oxide thermal barrier coating.
Claim 14
Dependent Claim
29 words
The vessel of claim 11 wherein between the metallic undercoating and the oxide thermal barrier coating there is at least one layer of a mixture of metal and oxide.
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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) | 1993-02-05 | 1993-08-07 | 1994-02-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-02-05 | 1997-08-07 | 1998-02-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-02-05 | 2001-08-07 | 2002-02-06 | $7700.00 | Window Closed / Lapsed |