Patent US4711707A successfully refreshed from Google Patents.
US4711707A
Expired / Lapsed
US
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Method for removal of scale from hot rolled steel
Assignee: National Institute of Advanced Industrial Science and Technology
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Filing: 1987-01-16
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Granted: 1987-12-08
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Expires: 2007-01-16
Abstract
Abstract The scale formed on stainless steel during the course of hot rolling is removed quickly and perfectly by subjecting the scale-covered steel to anode electrolysis in an aqueous sodium sulfate solution and subsequently to anode electrolysis in an aqueous sodium chloride solution.
Inventors
- 👤 Kaoru Kikuchi
- 👤 Nobuo Shikata
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 18:56
CPC Classifications
C; C25; C25F; C25F1/00; C25F1/02; C25F1/04; C25F1/06
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
95 words
A method for the removal of scale from hot rolled steel, which comprises subjecting said steel covered with scale to anode electrolysis in an aqueous 5 to 20% sodium sulfate solution at a current density in the range of 0.2 to 1.2 A/cm 2 for a period of 30 to 60 seconds, and then subjecting said steel resulting from said anode electrolysis to anode electrolysis in an aqueous 5 to 20% sodium chloride solution at a current density in the range of 0.3 to 0.5 A/cm 2 for a period of 30 to 60 seconds.
Claim 2
Independent Claim
95 words
A method for the removal of scale from hot rolled steel, which comprises subjecting said steel covered with scale to anode electrolysis in an aqueous 5 to 20% sodium sulfate solution at a current density in the range of 0.2 to 1.2 A/cm 2 for a period of 30 to 60 seconds, and then subjecting said steel resulting from said anode electrolysis to anode electrolysis in an aqueous 5 to 20% sodium chloride solution at a current density in the range of 0.3 to 0.5 A/cm 2 for a period of 30 to 60 seconds.
Claim 3
Dependent Claim
16 words
The method of claim 1, wherein said steel is SUS 304 steel or SUS 430 steel.
Claim 4
Dependent Claim
14 words
The method of claim 1, wherein said scale contains magnetite, wustite, and chromium sesquioxide.
Claim 5
Dependent Claim
26 words
The method of claim 1, wherein the two treatments of anode electrolysis are carried out at temperatures in the range of 20° C. to 80° C.
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) | 1990-12-07 | 1991-06-08 | 1991-12-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-12-07 | 1995-06-08 | 1995-12-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-12-07 | 1999-06-08 | 1999-12-08 | $7700.00 | Window Closed / Lapsed |