Patent US2984954A successfully refreshed from Google Patents.
US4493733A
Expired / Lapsed
US
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Corrosion-resistant non-magnetic steel retaining ring for a generator
Assignee: Toshiba Corp
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Filing: 1983-09-28
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Granted: 1985-01-15
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Expires: 2003-09-28
Abstract
Abstract Disclosed is a corrosion-resistant non-magnetic steel comprising, in terms of weight percentage, 0.4% or less of carbon, above 0.3% but up to 1% of nitrogen, 2% of less of silicon, 12 to 20% of chromium, 13 to 25% of manganese and the balance consisting substantially of iron, the total content of the chromium and manganese being at least 30%.
Inventors
- 👤 Masao Yamamoto
- 👤 Takashi Yebisuya
- 👤 Mituo Kawai
- 👤 Koichi Tajima
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 18:33
CPC Classifications
C; C22; C22C; C22C38/00; C22C38/18; C22C38/38
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
80 words
A non-magnetic, crevice corrosion resistant steel retaining ring for a generator consisting essentially of, in terms of weight percentage, 0.4% or less of carbon, above 0.3% but up to 1% of nitrogen, 2% or less of silicon, 12 to 20% of chromium, 13 to 25% of manganese, the balance consisting substantially of iron, the total content of the chromium and manganese being at least 30%, said retaining ring manufactured by cold working and having a magnetic permeability less than 1.1.
Claim 2
Dependent Claim
80 words
A non-magnetic, crevice corrosion resistant steel retaining ring for a generator consisting essentially of, in terms of weight percentage, 0.4% or less of carbon, above 0.3% but up to 1% of nitrogen, 2% or less of silicon, 12 to 20% of chromium, 13 to 25% of manganese, the balance consisting substantially of iron, the total content of the chromium and manganese being at least 30%, said retaining ring manufactured by cold working and having a magnetic permeability less than 1.1.
Claim 3
Dependent Claim
23 words
A retaining ring for a generator according to claim 1, wherein said retaining ring further comprises 5% by weight or less of molybdenum.
Claim 4
Dependent Claim
65 words
A retaining ring for a generator according to claim 1, wherein said corrosion-resistant non-magnetic steel comprises, in terms of weight percentage, 0.3% or less of carbon, 0.4 to 0.8% of nitrogen, 1.5% or less of silicon, 13 to 18% of chromium, 15 to 24% of manganese and the balance consisting substantially of iron, the total content of the chromium and manganese being at least 32%.
Claim 5
Dependent Claim
22 words
A retaining ring for a generator according to claim 3, wherein the content of said molybdenum is 1.0 to 2.5% by weight.
Claim 6
Dependent Claim
65 words
A retaining ring for a generator according to claim 2, wherein said corrosion-resistant non-magnetic steel comprises, in terms of weight percentage, 0.3% or less of carbon, 0.4 to 0.8% of nitrogen, 1.5% or less of silicon, 13 to 18% of chromium, 15 to 24% of manganese and the balance consisting substantially of iron, the total content of the chromium and manganese being at least 32%.
Claim 7
Dependent Claim
22 words
A retaining ring for a generator according to claim 5, wherein the content of said molybdenum is 1.0 to 2.5% by weight.
References Cited (Backward Citations)
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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) | 1988-01-15 | 1988-07-16 | 1989-01-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-01-15 | 1992-07-16 | 1993-01-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-01-15 | 1996-07-16 | 1997-01-15 | $7700.00 | Window Closed / Lapsed |