US4282047A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of producing steel pipe material for oil well
Assignee: JFE Steel Corp
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Filing: 1979-08-29
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Granted: 1981-08-04
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Expires: 1999-08-29
Abstract
Abstract The method of producing steel pipe material for an oil well is characterized in that, as for the chemical composition of steel, B contained steel is adopted avoiding the addition of Ti which increases the values of non-metallic inclusions to decrease machinability, the value of N is limited to not more than 0.003% to be decreased in content of nitrides, coarse crystal grains due to the decreased content of N are prevented through austenizing of steel under rapid heating, so that such a steel pipe material for an oil well can be obtained that which has resistance to sulfide stress corrosion in addition to satisfactory strength and machinability.
Inventors
- 👤 Mitsukuni Yamagata
- 👤 Keiichiro Takitani
- 👤 Sadao Hasuno
- 👤 Kuniaki Motoda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 10:19
CPC Classifications
C; C21; C21D; C21D9/00; C21D9/08; C21D9/14; Y; Y10; Y10S; Y10S148/00; Y10S148/902; Y10S148/909
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
124 words
A method of producing steel pipe material for an oil well, wherein a steel consisting essentially of in weight ratio from 0.15 to 0.50% C, from 0.1 to 1.0% Si, from 0.3 to 1.5% Mn, from 0.003 to 0.10% Al, from 0.0005 to 0.005% B, not more than 0.003% N, the balance being essentially Fe and inevitable impurities is heated at a temperature ranging from the transformation point Ac 1 to the transformation point Ac 3 plus 50° C. at an average heating rate of 1°-30° C./sec, quenched at the heating temperature ranging from the transformation point Ac 3 plus 50° C. to the crystal grain coarsening initiating temperature, and thereafter, tempered at a temperature not higher than the transformation point Ac 1 .
Claim 2
Independent Claim
124 words
A method of producing steel pipe material for an oil well, wherein a steel consisting essentially of in weight ratio from 0.15 to 0.50% C, from 0.1 to 1.0% Si, from 0.3 to 1.5% Mn, from 0.003 to 0.10% Al, from 0.0005 to 0.005% B, not more than 0.003% N, the balance being essentially Fe and inevitable impurities is heated at a temperature ranging from the transformation point Ac 1 to the transformation point Ac 3 plus 50° C. at an average heating rate of 1°-30° C./sec, quenched at the heating temperature ranging from the transformation point Ac 3 plus 50° C. to the crystal grain coarsening initiating temperature, and thereafter, tempered at a temperature not higher than the transformation point Ac 1 .
Claim 3
Independent Claim
165 words
A method of producing steel pipe material for an oil well, wherein a steel consisting essentially of, in weight ratio, from 0.15 to 0.50% C, from 0.1 to 1.0% Si, from 0.3 to 1.5% Mn, from 0.003 to 0.10% Al, from 0.0005 to 0.005% B, not more than 0.003% N, and further containing a member or more selected from the group consisting, in weight ratio, of from 0.05 to 1.50% Cr, from 0.05 to 1.0% Mo, from 0.01 to 0.10% Nb, from 0.01 to 0.10% V, from 0.05 to 0.50% Cu, the balance being essentially Fe and inevitable impurities is heated at a temperature ranging from the transformation point Ac 1 to the transformation point Ac 3 plus 50° C. at an average heating rate of 1°-30° C./sec, quenched at the heating temperature ranging from the transformation point Ac 3 plus 50° C. to the crystal grain coarsening initiating temperature, and thereafter, tempered at a temperature not higher than the transformation point Ac 1 .
Claim 4
Independent Claim
165 words
A method of producing steel pipe material for an oil well, wherein a steel consisting essentially of, in weight ratio, from 0.15 to 0.50% C, from 0.1 to 1.0% Si, from 0.3 to 1.5% Mn, from 0.003 to 0.10% Al, from 0.0005 to 0.005% B, not more than 0.003% N, and further containing a member or more selected from the group consisting, in weight ratio, of from 0.05 to 1.50% Cr, from 0.05 to 1.0% Mo, from 0.01 to 0.10% Nb, from 0.01 to 0.10% V, from 0.05 to 0.50% Cu, the balance being essentially Fe and inevitable impurities is heated at a temperature ranging from the transformation point Ac 1 to the transformation point Ac 3 plus 50° C. at an average heating rate of 1°-30° C./sec, quenched at the heating temperature ranging from the transformation point Ac 3 plus 50° C. to the crystal grain coarsening initiating temperature, and thereafter, tempered at a temperature not higher than the transformation point Ac 1 .
References Cited (Backward Citations)
US3992231A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-08-03 | 1985-02-02 | 1985-08-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-08-03 | 1989-02-02 | 1989-08-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-08-03 | 1993-02-02 | 1993-08-04 | $7700.00 | Window Closed / Lapsed |