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Patent US3475287A successfully refreshed from Google Patents.
US3475287A
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US
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Fractional distillation system with plural feeds,reboilers and side streams having internal reflux controls
Assignee: Universal Oil Products Co
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Filing: 1968-05-16
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Granted: 1969-10-28
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Expires: 1988-05-16
Abstract
No abstract record available.
Inventors
- 👤 Richard R De Graff
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 03:44
CPC Classifications
B; B01; B01D; B01D3/00; B01D3/42; B01D3/4211; B01D3/4222; Y; Y10; Y10S; Y10S203/00; Y10S203/19
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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US3212997A
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US3338799A
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US3405035A
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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) | 1972-10-27 | 1973-04-28 | 1973-10-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-10-27 | 1977-04-28 | 1977-10-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-10-27 | 1981-04-28 | 1981-10-28 | $7700.00 | Window Closed / Lapsed |