Patent US4152568A successfully refreshed from Google Patents.
US4152568A
Expired / Lapsed
US
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Method of arc welding with reverse side cooling for obtaining highly tough large-diameter welded steel pipes
Assignee: JFE Engineering Corp
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Filing: 1978-04-12
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Granted: 1979-05-01
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Expires: 1998-04-12
Abstract
Abstract An arc welding method for manufacture of a welded steel pipe wherein the edges of a steel plate bent into a pipe shape are welded together on one side for forming a pipe and then the seam line of the thus formed pipe is welded by a second welding operation at the side opposite to the side where the first welding was performed. During such second welding, the weld is cooled forcedly from the side where the first welding was performed. Such forced cooling compensates for any physical effects accompanying the welding and imparts elevated toughness to both the weld metal and the heat affected zone.
Inventors
- 👤 Tetsuo Yamaguchi
- 👤 Tadaaki Taira
- 👤 Kiyoteru Hirabayashi
- 👤 Yukio Nishino
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 18:11
CPC Classifications
B; B23; B23K; B23K37/00; B23K37/003; B23K31/00; B23K31/02; B23K31/027
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
125 words
A method of arc welding a steel pipe formed by a steel plate bent into pipe shape with abutting ends, said method comprising welding a seam at the abutting ends by conveying the pipe through leading and trailing passes and forming bead layers on opposite sides of a weld zone during respective passes, and effecting the formation of the bead layer of the weld zone during the trailing pass with a heat input of more than 36,000J/cm while effecting forced cooling of the weld zone from the reverse side simultaneously, the forced cooling being effected to cool the weld from the weld temperature to 800° C. within 11 seconds and from 800° C. to 500° C. at a cooling rate of 8-40° C. per second.
Claim 2
Independent Claim
125 words
A method of arc welding a steel pipe formed by a steel plate bent into pipe shape with abutting ends, said method comprising welding a seam at the abutting ends by conveying the pipe through leading and trailing passes and forming bead layers on opposite sides of a weld zone during respective passes, and effecting the formation of the bead layer of the weld zone during the trailing pass with a heat input of more than 36,000J/cm while effecting forced cooling of the weld zone from the reverse side simultaneously, the forced cooling being effected to cool the weld from the weld temperature to 800° C. within 11 seconds and from 800° C. to 500° C. at a cooling rate of 8-40° C. per second.
Claim 3
Dependent Claim
33 words
A method as claimed in claim 1 wherein the bead layer of the weld zone in the forward welding pass is effected by submerged arc welding using front and rear Ni-Mo-Ti electrode wires.
Claim 4
Dependent Claim
37 words
The method as claimed in claim 1 wherein the forced cooling is performed at a rate of 15 to 30° C. per second until the temperature of the weld is cooled from 800° C. to 500° C.
Claim 5
Dependent Claim
14 words
The method as claimed in claim 1 wherein water is used as cooling medium.
Claim 6
Dependent Claim
15 words
The method as claimed in claim 1 wherein liquid nitrogen is used as cooling medium.
Claim 7
Dependent Claim
16 words
The method as claimed in claim 1 wherein the dry ice is used as cooling medium.
References Cited (Backward Citations)
US2716691A
Cited
GB997934A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-04-30 | 1982-10-30 | 1983-05-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-04-30 | 1986-10-30 | 1987-05-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-04-30 | 1990-10-30 | 1991-05-01 | $7700.00 | Window Closed / Lapsed |