Patent US3993433A successfully refreshed from Google Patents.
US3993433A
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US
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Cylindrical elongated furnace for treating material at high temperature in a gaseous atmosphere under high pressure
Assignee: ABB Norden Holding AB
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Filing: 1975-08-21
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Granted: 1976-11-23
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Expires: 1995-08-21
Abstract
Abstract In a cylindrical elongated furnace for treating materials at high temperature in a gaseous atmosphere under high pressure, there is a vertical cylindrical pressure chamber forming a furnace space surrounded by a cylindrical heater, with an insulating sheath around the furnace space and the heater formed of a number of metal tubes with insulation between them. At least one of the metal tubes is suspended from a supporting member at the upper part of the insulating sheath and is provided at its lower part with a number of slots extending upwardly from the bottom edge.
Inventors
- 👤 Sven-Erik Isaksson
- 👤 Bo Christer Jakobsson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 20:09
CPC Classifications
B; B30; B30B; B30B11/00; B30B11/001; B30B11/002; B01; B01J; B01J3/00; B01J3/04; B01J3/048; B22; B22F; B22F3/00; B22F3/12; B22F3/14; B22F3/15; F; F27; F27B; F27B5/00; F27B5/04; F27D; F27D1/00; F27D11/00; F27D11/02; H; H05; H05B; H05B3/00; H05B3/62; H05B3/64; F27B17/00; F27B17/0016; F27B17/0033; F27D1/04; F27D2001/0059; F27D2001/0066; F27D99/00; F27D99/0001; F27D99/0006; F27D2099/0008; F27D2099/0085; F27D2099/0096; F27D21/00; F27D21/0014
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
114 words
Cylindrical elongated furnace for treating materials at high temperature in a gaseous atmosphere under high pressure, comprising a vertical cylindrical pressure chamber capable of confining a gas under high pressure, a furnace space, a cylindrical heater around the furnace space, an insulating sheath surrounding the furnace space and the heater, which is formed of a number of metal tubes and insulation applied between the tubes, and an insulating lid and an insulating bottom at the ends of the insulating sheath, the insulating sheath comprising a metal tube suspended from a supporting member at the upper part of the insulating sheath and provided at its lower part with a number of slots running substantially vertically.
Claim 2
Dependent Claim
114 words
Cylindrical elongated furnace for treating materials at high temperature in a gaseous atmosphere under high pressure, comprising a vertical cylindrical pressure chamber capable of confining a gas under high pressure, a furnace space, a cylindrical heater around the furnace space, an insulating sheath surrounding the furnace space and the heater, which is formed of a number of metal tubes and insulation applied between the tubes, and an insulating lid and an insulating bottom at the ends of the insulating sheath, the insulating sheath comprising a metal tube suspended from a supporting member at the upper part of the insulating sheath and provided at its lower part with a number of slots running substantially vertically.
Claim 3
Dependent Claim
18 words
Furnace according to claim 1, in which the innermost tube of the insulating sheath is provided with slots.
Claim 4
Dependent Claim
16 words
Furnace according to claim 1, in which at least two suspended tubes are formed with slots.
Claim 5
Dependent Claim
23 words
Furnace according to claim 1, in which the outer tube of the insulating sheath supports said supporting member and metal tubes suspended therein.
Claim 6
Dependent Claim
12 words
Furnace according to claim 1, in which the slots are axially oriented.
Claim 7
Dependent Claim
24 words
Furnace according to claim 5, in which the length of the slots is 100-500 mm and the distance between the slots is 30-100 mm.
Claim 8
Dependent Claim
18 words
Furnace according to claim 5, in which the tube portion with slots is provided with a supporting ring.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-11-23 | 1980-05-24 | 1980-11-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-11-23 | 1984-05-24 | 1984-11-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-11-23 | 1988-05-24 | 1988-11-23 | $7700.00 | Window Closed / Lapsed |