Patent US3427277A successfully refreshed from Google Patents.
Patent US2569158A successfully refreshed from Google Patents.
US2569158A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of removing scale from ferrous articles
Assignee: United States Steel Corp
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Filing: 1946-02-21
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Granted: 1951-09-25
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Expires: 1966-02-21
Abstract
No abstract record available.
Inventors
- 👤 Charles B Francis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 15:32
CPC Classifications
C; C23; C23G; C23G1/00; C23G1/28; C23G1/32
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
45 words
IN A METHOD OF DESCALING ARTICLES OF STAINLESS STEEL, THE STEPS INCLUDING IMMERSING THE ARTICLES IN A BATH OF FUSED SODIUM HYDROXIDE, PICKLING THE ARTICLES IN A DILUTE AQUEOUS SOLUTION OF SULPHURIC ACID, AND THEN DIPPING THEM IN A DILUTE AQUEOUS SOLUTION OF NITRIC ACID.
Claim 2
Dependent Claim
45 words
IN A METHOD OF DESCALING ARTICLES OF STAINLESS STEEL, THE STEPS INCLUDING IMMERSING THE ARTICLES IN A BATH OF FUSED SODIUM HYDROXIDE, PICKLING THE ARTICLES IN A DILUTE AQUEOUS SOLUTION OF SULPHURIC ACID, AND THEN DIPPING THEM IN A DILUTE AQUEOUS SOLUTION OF NITRIC ACID.
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) | 1954-09-24 | 1955-03-26 | 1955-09-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-09-24 | 1959-03-26 | 1959-09-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-09-24 | 1963-03-26 | 1963-09-25 | $7700.00 | Window Closed / Lapsed |