US3716908A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for welding
Assignee: American Brass Co
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Filing: 1971-09-27
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Granted: 1973-02-20
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Expires: 1991-09-27
Abstract
Abstract A method and apparatus for the continuous production of welded tube from a continuous length of strip material wherein the welded seam is cold worked and wherein the physical nature of the welded seam is continuously monitored to insure that a proper weld is produced is described herein.
Inventors
- 👤 D Rowell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 14:57
CPC Classifications
B; B23; B23K; B23K9/00; B23K9/02; B23K9/025; B23K9/0253; B21; B21C; B21C37/00; B21C37/06; B21C37/08; B21C37/0807
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
129 words
A method for continuously producing a welded tube from a continuous length of strip material and testing the formed tube to reveal any weaknesses comprising a. forming the strip material into a tubular form so that the edges of the strip are in a weldable arrangement; b. welding the edges of the strip to form a continuous tube having a welded seam; c. cold working the welded seam which cold working in turn comprises i. supporting a portion of the interior wall of the tube which includes the welded seam; ii. applying pressure to the outside of the supported wall portion which pressure is greater than the yield point of the welded seam; and e. expanding the tube after such cold working to reveal any weakness in the seam.
Claim 2
Independent Claim
129 words
A method for continuously producing a welded tube from a continuous length of strip material and testing the formed tube to reveal any weaknesses comprising a. forming the strip material into a tubular form so that the edges of the strip are in a weldable arrangement; b. welding the edges of the strip to form a continuous tube having a welded seam; c. cold working the welded seam which cold working in turn comprises i. supporting a portion of the interior wall of the tube which includes the welded seam; ii. applying pressure to the outside of the supported wall portion which pressure is greater than the yield point of the welded seam; and e. expanding the tube after such cold working to reveal any weakness in the seam.
Claim 3
Independent Claim
129 words
A method for continuously producing a welded tube from a continuous length of strip material and testing the formed tube to reveal any weaknesses comprising a. forming the strip material into a tubular form so that the edges of the strip are in a weldable arrangement; b. welding the edges of the strip to form a continuous tube having a welded seam; c. cold working the welded seam which cold working in turn comprises i. supporting a portion of the interior wall of the tube which includes the welded seam; ii. applying pressure to the outside of the supported wall portion which pressure is greater than the yield point of the welded seam; and e. expanding the tube after such cold working to reveal any weakness in the seam.
Claim 4
Independent Claim
129 words
A method for continuously producing a welded tube from a continuous length of strip material and testing the formed tube to reveal any weaknesses comprising a. forming the strip material into a tubular form so that the edges of the strip are in a weldable arrangement; b. welding the edges of the strip to form a continuous tube having a welded seam; c. cold working the welded seam which cold working in turn comprises i. supporting a portion of the interior wall of the tube which includes the welded seam; ii. applying pressure to the outside of the supported wall portion which pressure is greater than the yield point of the welded seam; and e. expanding the tube after such cold working to reveal any weakness in the seam.
Claim 5
Dependent Claim
29 words
The method of claim 1 in which the pressure used to support the interior tube wall is substantially less than the pressure applied to the outside of the tube.
Claim 6
Dependent Claim
29 words
The method of claim 1 having in addition the step of confining gas under a known pressure in the tube after its expansion and sensing changes in such pressure.
Claim 7
Dependent Claim
30 words
The method of claim 1 in which substantially the entire outside portion of tube wall diametrically opposite the area to which pressure is applied is supported during the pressure application.
References Cited (Backward Citations)
US2959849A
Cited
US3194466A
Cited
US3153845A
Cited
US3486219A
Cited
US3513682A
Cited
US3590622A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-02-20 | 1976-08-21 | 1977-02-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-02-20 | 1980-08-21 | 1981-02-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-02-20 | 1984-08-21 | 1985-02-20 | $7700.00 | Window Closed / Lapsed |