Patent US3958918A successfully refreshed from Google Patents.
US3958918A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for elimination of furnace roll pickup marks on silicon containing sheet steel
Assignee: United States Steel Corp
•
Filing: 1975-02-10
•
Granted: 1976-05-25
•
Expires: 1995-02-10
Abstract
Abstract A process for continuous annealing silicon containing sheet steel whereby furnace roll pickup marks are eliminated, said process involving the use of furnace rolls having a silica peripheral surface and maintaining an annealing atmosphere containing hydrogen to water at a ratio of at least 5:1.
Inventors
- 👤 Arthur R. Henricks
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 21:20
CPC Classifications
C; C21; C21D; C21D8/00; C21D8/12; C21D8/1244; C21D8/1255; C21D1/00; C21D1/74; C21D1/76; C21D9/00; C21D9/52; Y; Y02; Y02P; Y02P10/00; Y02P10/10; Y02P10/122
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
71 words
A process for continuous annealing a silicon containing sheet steel whereby furnace roll pickup is substantially eliminated, the process comprising continuously annealing said steel at a temperature of from 1,400° to 1,650°F in a furnace provided with furnace rolls having a silica peripheral surface, and maintaining in the furnace a decarburizing atmosphere containing hydrogen and water at a ratio sufficient to cause the formation of only silica on the steel surface.
Claim 2
Dependent Claim
71 words
A process for continuous annealing a silicon containing sheet steel whereby furnace roll pickup is substantially eliminated, the process comprising continuously annealing said steel at a temperature of from 1,400° to 1,650°F in a furnace provided with furnace rolls having a silica peripheral surface, and maintaining in the furnace a decarburizing atmosphere containing hydrogen and water at a ratio sufficient to cause the formation of only silica on the steel surface.
Claim 3
Dependent Claim
21 words
A process according to claim 1 in which said decarburizing atmosphere contains a hydrogen to water ratio of at least 5:1.
Claim 4
Dependent Claim
23 words
A process according to claim 1 in which said decarburizing atmosphere contains a hydrogen to water ratio within the range 5:1 to 8:1.
Claim 5
Dependent Claim
20 words
A process according to claim 1 in which said decarburizing atmosphere contains a hydrogen to water ratio of about 6:1.
Claim 6
Dependent Claim
17 words
A process according to claim 3 in which said decarburizing atmosphere contains from 20 to 80% hydrogen.
Claim 7
Dependent Claim
40 words
A process according to claim 1 in which said steel is subsequently heated to a temperature within the range 1,650° to 2,000°F in a second atmosphere containing a hydrogen to water ratio in excess of 8:1 to effect grain growth.
Claim 8
Dependent Claim
23 words
A process according to claim 6 in which said second atmosphere contains a hydrogen to water ratio within the range 8:1 to 30:1.
References Cited (Backward Citations)
US2753170A
Cited
US3751195A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-05-25 | 1979-11-24 | 1980-05-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-05-25 | 1983-11-24 | 1984-05-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-05-25 | 1987-11-24 | 1988-05-25 | $7700.00 | Window Closed / Lapsed |