Patent US3144329A successfully refreshed from Google Patents.
US3144329A
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US
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Method for producing rolled steel products
Assignee: Trafikaktiebolaget Grangesberg-Oxelosund
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Filing: 1961-09-05
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Granted: 1964-08-11
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Expires: 1981-09-05
Abstract
No abstract record available.
Inventors
- 👤 Frolich Ake Tjelvar
- 👤 Smedstam John Arne
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 16:29
CPC Classifications
C; C22; C22C; C22C33/00; C22C33/02; C22C33/0235; C21; C21B; C21B13/00; C21B13/0086; C21B13/0093; Y; Y02; Y02P; Y02P10/00; Y02P10/10; Y02P10/134
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
130 words
PROCESS FOR THE PRODUCTION OF ROLLED STEEL PRODUCTS WHICH COMPRISES FORMING A GROUND SPONGE IRON POWDER HAVING A SUBSTANTIAL CONTENT OF IRON OXIDE THE BULK OF WHICH IS EXPOSED AT THE SURFACES OF THE POWDER PARTICLES, ADJUSTING THE CARBON CONTENT OF SAID IRON POWDER TO THE STOICHIOMETRIC EQUIVALENT OF THE IRON OXIDE CONTENT THEREOF BY THE ADDITION OF A MEMBER SELECTED FROM THE GROUP CONSISTING OF PIG IRON AND CEMENTITE, COLD PRESSING SAID POWDER TO SHEET BARS HAVING A DENSITY OF AT LEAST 4 G./CM.3, SINTERING SAID BARS AT A TEMPERATURE OF 600-1200*C. WHEREBY THE OXYGEN AND CARBON CONTENTS OF THE BARS ARE SUBSTANTIALLY REDUCED, COMPRESSION ROLLING THE SINTERED BARS TO A DENSITY OF AT LEAST ABOUT 7 GM./CM.3, ANNEALING THE COMPRESSED ROLLED BARS AND COLD ROLLING THE ANNEALED BARS.
Claim 2
Dependent Claim
130 words
PROCESS FOR THE PRODUCTION OF ROLLED STEEL PRODUCTS WHICH COMPRISES FORMING A GROUND SPONGE IRON POWDER HAVING A SUBSTANTIAL CONTENT OF IRON OXIDE THE BULK OF WHICH IS EXPOSED AT THE SURFACES OF THE POWDER PARTICLES, ADJUSTING THE CARBON CONTENT OF SAID IRON POWDER TO THE STOICHIOMETRIC EQUIVALENT OF THE IRON OXIDE CONTENT THEREOF BY THE ADDITION OF A MEMBER SELECTED FROM THE GROUP CONSISTING OF PIG IRON AND CEMENTITE, COLD PRESSING SAID POWDER TO SHEET BARS HAVING A DENSITY OF AT LEAST 4 G./CM.3, SINTERING SAID BARS AT A TEMPERATURE OF 600-1200*C. WHEREBY THE OXYGEN AND CARBON CONTENTS OF THE BARS ARE SUBSTANTIALLY REDUCED, COMPRESSION ROLLING THE SINTERED BARS TO A DENSITY OF AT LEAST ABOUT 7 GM./CM.3, ANNEALING THE COMPRESSED ROLLED BARS AND COLD ROLLING THE ANNEALED BARS.
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) | 1967-08-11 | 1968-02-10 | 1968-08-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1971-08-11 | 1972-02-10 | 1972-08-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1975-08-11 | 1976-02-10 | 1976-08-11 | $7700.00 | Window Closed / Lapsed |