US4238121A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Hearth structure of an oxygen-bottom-blowing converter
Assignee: JFE Steel Corp
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Filing: 1978-10-04
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Granted: 1980-12-09
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Expires: 1998-10-04
Abstract
Abstract A hearth structure of an oxygen-bottom-blowing converter comprises hearth bricks including a number of brick row units, each of which is provided with or without one tuyere therein to eliminate thermal stresses otherwise be caused by two tuyeres included in one brick row unit. The hearth bricks preferably include at least one row of bricks not including a tuyere arranged between the brick row units. Bricks around tuyeres are unburned magnesia-carbon or magnesia-dolomite-carbon bricks including an amount of carbon 7-35%, preferably 10-30% or the most preferably 20% by weight and including magnesia or magnesia-dolomite as grains and thicknesses of refractory mortar as joints between the bricks corresponding to 0.5-2.5% of the maximum width of the bricks, thereby improving the durability of the hearth structure and hence the converter.
Inventors
- 👤 Akira Harita
- 👤 Tadashi Morimoto
- 👤 Toshio Kanatani
- 👤 Ryoji Uchimura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 06:26
CPC Classifications
C; C21; C21C; C21C5/00; C21C5/28; C21C5/42; C21C5/46; C21C5/48
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
138 words
In a hearth structure of an oxygen-bottom-blowing converter, including a plurality of tuyeres extending through said structure and opening into an inside of said converter for oxygen-blowing, and monolithic refractories filled between converter lining and hearth lining including said tuyeres, the improvement comprising said hearth lining including a plurality of brick row units, a plurality of which is provided with a single tuyere per row unit, wherein the row units have a chord direction substantially parallel to each other, and the brick ends in adjacent brick row units are shifted in the chord direction relative to the brick ends in an adjacent row unit, so that a brick row unit including a tuyere would also be shifted in the chord direction from other tuyeres and thereby eliminate thermal stresses acting upon the bricks and causing the wearing thereof.
Claim 2
Dependent Claim
138 words
In a hearth structure of an oxygen-bottom-blowing converter, including a plurality of tuyeres extending through said structure and opening into an inside of said converter for oxygen-blowing, and monolithic refractories filled between converter lining and hearth lining including said tuyeres, the improvement comprising said hearth lining including a plurality of brick row units, a plurality of which is provided with a single tuyere per row unit, wherein the row units have a chord direction substantially parallel to each other, and the brick ends in adjacent brick row units are shifted in the chord direction relative to the brick ends in an adjacent row unit, so that a brick row unit including a tuyere would also be shifted in the chord direction from other tuyeres and thereby eliminate thermal stresses acting upon the bricks and causing the wearing thereof.
Claim 3
Dependent Claim
20 words
A hearth structure as set forth in claim 1, wherein said brick row unit consists of two rows of bricks.
Claim 4
Dependent Claim
40 words
A hearth structure as set forth in claim 1, wherein at least one row of bricks not including any tuyere is arranged between said brick row units respectively including one tuyere to reduce shearing stresses between said brick row units.
Claim 5
Dependent Claim
34 words
A hearth structure as set forth in claim 1, wherein thicknesses of refractory mortar as joints between said brick row units correspond to 0.5-2.5% of the maximum width of the bricks at operating surfaces.
Claim 6
Dependent Claim
37 words
A hearth structure as set forth in claim 1, wherein thicknesses of refractory mortar as joints between the bricks in said brick row units correspond to 0.5-2.5% of the maximum width of the bricks at operating surfaces.
Claim 7
Dependent Claim
43 words
A hearth structure as set forth in claim 1, wherein thicknesses of refractory mortar as joints between said brick row units and between the bricks in said brick row units correspond to 0.5-2.5% of the maximum width of the bricks at operating surfaces.
Claim 8
Dependent Claim
36 words
A hearth structure as set forth in claim 1, wherein bricks arranged around said tuyeres are unburned magnesia-carbon or magnesia-dolomite-carbon bricks including an amount of carbon 7-35% by weight and including magnesia or magnesia-dolomite as grains.
Claim 9
Dependent Claim
36 words
A hearth structure as set forth in claim 1, wherein bricks arranged around said tuyeres are unburned magnesia-carbon or magnesia-dolomite-carbon bricks including an amount of carbon 10-30% by weight and including magnesia or magnesia-dolomite as grains.
Claim 10
Dependent Claim
36 words
A hearth structure as set forth in claim 1, wherein bricks arranged around said tuyeres are unburned magnesia-carbon or magnesia-dolomite-carbon bricks including an amount of carbon 20% by weight and including magnesia or magnesia-dolomite as grains.
References Cited (Backward Citations)
US4130438A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-12-09 | 1984-06-09 | 1984-12-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-12-09 | 1988-06-09 | 1988-12-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-12-09 | 1992-06-09 | 1992-12-09 | $7700.00 | Window Closed / Lapsed |