Patent US4066521A successfully refreshed from Google Patents.
US4066521A
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Metallic descaling system
Assignee: Allegheny Ludlum Corp
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Filing: 1977-02-09
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Granted: 1978-01-03
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Expires: 1997-02-09
Abstract
Abstract A process for descaling a metallic body, wherein a heated body is immersed in a bath of a molten oxidizing salt, and subsequently in an electrolyte of an aqueous solution of at least one neutral salt from the group consisting of the chloride, sulfate and nitrate of an alkali metal or ammonium.
Inventors
- 👤 Donald R. Zaremski
- 👤 Albert Krepler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 19:47
CPC Classifications
C; C25; C25F; C25F1/00; C25F1/02; C25F1/04; C25F1/06; C23; C23G; C23G1/00; C23G1/28
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
125 words
A process for descaling a heated metallic body, which comprises the steps of: immersing said body in a bath of molten oxidizing salt; maintaining said bath at a temperature above its melting point during said immersion, said immersion being for a period of more than 2 and less than 30 seconds; removing said body from said bath after scale on said body has been conditioned for subsequent removal; subsequently immersing said body in an electrolyte of an aqueous solution of at least one neutral salt from the group consisting of the chloride, sulfate and nitrate of an alkali metal or ammonium; passing an electric current through said body and electrolyte for a period of at least 4 seconds; and removing said body from said electrolyte.
Claim 2
Dependent Claim
125 words
A process for descaling a heated metallic body, which comprises the steps of: immersing said body in a bath of molten oxidizing salt; maintaining said bath at a temperature above its melting point during said immersion, said immersion being for a period of more than 2 and less than 30 seconds; removing said body from said bath after scale on said body has been conditioned for subsequent removal; subsequently immersing said body in an electrolyte of an aqueous solution of at least one neutral salt from the group consisting of the chloride, sulfate and nitrate of an alkali metal or ammonium; passing an electric current through said body and electrolyte for a period of at least 4 seconds; and removing said body from said electrolyte.
Claim 3
Dependent Claim
22 words
A process according to claim 1, wherein said bath contains a compound from the group consisting of potassium nitrate and sodium nitrate.
Claim 4
Dependent Claim
34 words
a process according to claim 1, wherein said electrolyte contains from 0.1 to 50 grams per liter of a compound from the group consisting of fluorides, chlorides, perchlorates, chromates, nitrites, sulfites, nitrates and sulfates.
Claim 5
Dependent Claim
13 words
A process according to claim 1, wherein the neutral salt is sodium sulfate.
Claim 6
Dependent Claim
14 words
A process according to claim 1, wherein said metallic body is an alloy steel.
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) | 1981-01-02 | 1981-07-04 | 1982-01-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-01-02 | 1985-07-04 | 1986-01-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-01-02 | 1989-07-04 | 1990-01-03 | $7700.00 | Window Closed / Lapsed |