Patent US3920948A successfully refreshed from Google Patents.
US3920948A
Expired / Lapsed
US
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Method for repairing ingot stools
Assignee: Hoogovens Ijmuiden BV
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Filing: 1974-01-02
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Granted: 1975-11-18
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Expires: 1994-01-02
Abstract
Abstract A method of repairing a heavy iron article (for example, ingot stools and ingot moulds) in which metal of a composition substantially that of the metal of the article to be repaired (except for alloying components, flux, and covering substances) is supplied to the portion to be repaired. The metal supplied and portion to be repaired are electrothermally heated to render them molten for a substantial period of time by applying electrothermal power of at least 250 kVA adjacent the portion of the article to be assembled in a reducing environment for a part of the time and then the article is slowly cooled.
Inventors
- 👤 Jan Schokkenbroek
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 04:34
CPC Classifications
B; B22; B22D; B22D7/00; B22D7/06; B22D7/066; B23; B23K; B23K35/00; B23K35/22; B23K35/38; B23K9/00; B23K9/04; B23P; B23P6/00; B23P6/04; B23K2103/00; B23K2103/02; B23K2103/06
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
138 words
A method of repairing a heavy metal article comprising the sequential steps of: electrothermally heating the portion of the article to be repaired by applying electrothermal power adjacent the portion of the article to be repaired in a reducing environment, supplying metal to the portion of the article to be repaired, said metal being of a composition substantially that of the metal of the article to be repaired except for alloying components, flux, and covering substances, electrothermally heating the metal supplied and the portion of the article to be repaired to render them molten for a substantial period of time by applying electrothermal power of at least 250 kVA adjacent the portion of the article to be repaired while maintaining the reducing environment for at least a substantial part of the time, and then slowly cooling the article.
Claim 2
Independent Claim
138 words
A method of repairing a heavy metal article comprising the sequential steps of: electrothermally heating the portion of the article to be repaired by applying electrothermal power adjacent the portion of the article to be repaired in a reducing environment, supplying metal to the portion of the article to be repaired, said metal being of a composition substantially that of the metal of the article to be repaired except for alloying components, flux, and covering substances, electrothermally heating the metal supplied and the portion of the article to be repaired to render them molten for a substantial period of time by applying electrothermal power of at least 250 kVA adjacent the portion of the article to be repaired while maintaining the reducing environment for at least a substantial part of the time, and then slowly cooling the article.
Claim 3
Dependent Claim
37 words
The method of claim 1 wherein: the reducing environment in which said electrothermal power of at least 250 kVA is applied is maintained thereby at a temperature of at least 1500*C for a substantial period of time.
Claim 4
Dependent Claim
22 words
The method of claim 2 wherein: the temperature at which the reducing environment is maintained is in the range 2300*C to 2600*C.
Claim 5
Dependent Claim
24 words
The method of claim 1 wherein: the electrothermal power applied in the reducing environment before the metal is supplied is at least 250 kVA.
Claim 6
Dependent Claim
37 words
The method of claim 1 further comprising the step of: supplying granular material to the portion of the article to be repaired, the granular material producing a reducing gas upon said heating to produce the reducing environment.
Claim 7
Dependent Claim
11 words
The method of claim 5 wherein: the granular material is coke.
Claim 8
Dependent Claim
96 words
The method of claim 6 wherein: said power is applied by means of an electrode adjacent the portion of the article to be repaired, said coke is supplied in a large volume around the electrode, said power is applied until the portion of the article to be repaired is molten, then said electrode is removed from the coke to leave a hole therein, then said metal is supplied as aforesaid, then the electrode is returned to its position adjacent the article to be repaired and said power is again applied for at least about 2 hours.
Claim 9
Dependent Claim
14 words
The method of claim 1 wherein said article is a cast iron ingot stool.
Claim 10
Dependent Claim
14 words
The method of claim 1 wherein said article is a cast iron ingot mould.
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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) | 1978-11-17 | 1979-05-19 | 1979-11-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-11-17 | 1983-05-19 | 1983-11-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-11-17 | 1987-05-19 | 1987-11-18 | $7700.00 | Window Closed / Lapsed |