Patent EP0003642A2 successfully refreshed from Google Patents.
US3851091A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Furnace for reheating slabs or billets
Assignee: British Steel Corp
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Filing: 1973-10-26
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Granted: 1974-11-26
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Expires: 1993-10-26
Abstract
Abstract A reheating furnace for steel slabs or billets includes a plurality of generally parallel skids extending longitudinally of the furnace, a plurality of heat sources within the furnace and electric induction heaters associated with the skids for applying additional heat to the under surfaces of the workpieces. The induction heaters comprise a plurality of cores having electrically inductive windings thereon, each core being recessed in the soaking hearth of the furnace below a layer of refractory material and extending longitudinally of the hearth substantially in alignment with a respective skid.
Inventors
- 👤 W Laws
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 22:08
CPC Classifications
F; F27; F27B; F27B9/00; F27B9/14; F27B9/20; F27B9/22
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
77 words
A heating furnace for metal workpieces comprising a plurality of skids extending longitudinally of the furnace for supporting metal workpieces as they pass through the furnace; a plurality of heat sources located within the furnace and electric induction heating means located below the level of the tops of the skids for applying heat in discrete zones extending longitudinally of the furnace solely to the undersurfaces of the workpieces additional to the heat provided by said heat sources.
Claim 2
Dependent Claim
77 words
A heating furnace for metal workpieces comprising a plurality of skids extending longitudinally of the furnace for supporting metal workpieces as they pass through the furnace; a plurality of heat sources located within the furnace and electric induction heating means located below the level of the tops of the skids for applying heat in discrete zones extending longitudinally of the furnace solely to the undersurfaces of the workpieces additional to the heat provided by said heat sources.
Claim 3
Dependent Claim
77 words
A heating furnace for metal workpieces comprising a plurality of skids extending longitudinally of the furnace for supporting metal workpieces as they pass through the furnace; a plurality of heat sources located within the furnace and electric induction heating means located below the level of the tops of the skids for applying heat in discrete zones extending longitudinally of the furnace solely to the undersurfaces of the workpieces additional to the heat provided by said heat sources.
Claim 4
Dependent Claim
77 words
A heating furnace for metal workpieces comprising a plurality of skids extending longitudinally of the furnace for supporting metal workpieces as they pass through the furnace; a plurality of heat sources located within the furnace and electric induction heating means located below the level of the tops of the skids for applying heat in discrete zones extending longitudinally of the furnace solely to the undersurfaces of the workpieces additional to the heat provided by said heat sources.
Claim 5
Dependent Claim
26 words
A heating furnace as claimed in claim 1 wherein said induction heating means are located within the furnace downstream of said skids and in alignment therewith.
Claim 6
Dependent Claim
37 words
A heating furnace as claimed in claim 1 wherein a soaking hearth is provided downstream of said skids and said induction heating means are recessed within said hearth extending longitudinally thereof substantially in alignment with said skids.
Claim 7
Dependent Claim
38 words
A heating furnace as claiMed in claim 3 wherein said induction heating means are covered with refractory material providing a continuous bearing surface in the hearth for the workpieces as they pass through the hearth from said skids.
Claim 8
Dependent Claim
23 words
A heating furnace as claimed in claim 3 wherein said induction heating means extend longitudinally from end to end of the soaking hearth.
Claim 9
Dependent Claim
38 words
A heating furnace as claimed in claim 3 wherein said induction heating means comprise a plurality of cores having electrically inductive windings thereon, each core extending longitudinally of the soaking hearth substantially in alignment with a respective skid.
Claim 10
Dependent Claim
17 words
A heating furnace as claimed in claim 1 comprising a reheating furnace for steel slabs or billets.
Claim 11
Independent Claim
79 words
A method of heating metal workpieces during their passage through a heating furnace on a plurality of skids extending longitudinally of the furnace comprising applying heat to the workpieces from a plurality of heat sources within the furnace and applying heat, additional to the heat supplied by said heat sources, in discrete zones extending longitudinally of the furnace solely to the undersurfaces of the workpieces by electric induction heaters located below the level of the tops of the skids.
Claim 12
Independent Claim
79 words
A method of heating metal workpieces during their passage through a heating furnace on a plurality of skids extending longitudinally of the furnace comprising applying heat to the workpieces from a plurality of heat sources within the furnace and applying heat, additional to the heat supplied by said heat sources, in discrete zones extending longitudinally of the furnace solely to the undersurfaces of the workpieces by electric induction heaters located below the level of the tops of the skids.
Claim 13
Dependent Claim
23 words
A method according to claim 8 wherein the additional heat is applied to the under surfaces of the workpieces downstream of the skids.
Claim 14
Dependent Claim
40 words
A method according to claim 9 wherein the additional heat is applied to the under surfaces of the workpieces in a soaking hearth, downstream of the skids, in zones extending longitudinally of the hearth substantially in alignment with respective skids.
Claim 15
Dependent Claim
49 words
A heating furnace according to claim 11 wherein each of the transverse flux-type electric induction heaters comprises an elongated, generally E-shaped core with the limbs of the core extending vertically upwardly from the body portion of the core, and with multi-layer windings disposed in the space between said limbs.
Claim 16
Dependent Claim
28 words
A heating furnace according to claim 12 wherein said cores are covered with refractory material providing a continuous load bearing surface in the soaking zone for said workpieces.
References Cited (Backward Citations)
US3342468A
Cited
US3596036A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-11-25 | 1978-05-27 | 1978-11-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-11-25 | 1982-05-27 | 1982-11-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-11-25 | 1986-05-27 | 1986-11-26 | $7700.00 | Window Closed / Lapsed |