US3924095A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Narrow-groove welding
Assignee: Babcock and Wilcox Co
•
Filing: 1974-05-29
•
Granted: 1975-12-02
•
Expires: 1994-05-29
Abstract
Abstract Narrow groove welding wherein a consumable electrode is passed through a heat and electrically insulated welding head inserted in the narrow groove. Movement of the welding head in the narrow groove is controlled to coordinate vertical, longitudinal and lateral movement of the head relative to the welding position, and protective gas is used closely adacent the arc to form a high quality weld bead in the narrow gap.
Inventors
- 👤 Jr Matthew J Lucas
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 13:57
CPC Classifications
B; B23; B23K; B23K9/00; B23K9/02; B23K9/0213; B23K9/12; B23K9/133; B23K9/1336; B23K9/16; B23K9/173
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
241 words
In narrow groove welding the combination comprising a work piece having a narrow groove therein with substanTially parallel walls and a groove width substantially less than the depth thereof, an electric welding machine positioned exteriorly of the work piece and having a welding head projecting into the groove, means for positioning the welding head in a direction parallel to the depth of the groove, means for controlled relative movement of the work piece and the electric welding machine parallel to the narrow groove, means for feeding a consumable electrode wire through the welding head into the groove, means for applying electric power through the consumable electrode wire to form an arc between the end of the wire and the work piece to weld join walls of the groove whereby the weld metal fuses both sides of the groove equally in a single pass, control means for regulating the rate of electrode wire feed to the arc, means for maintaining the tip of the electrode wire centered in the groove by transverse movement of the welding head relative to the walls of the groove, means for passing a protecting gas through the welding head to surround the welding arc in the groove, a shield loosely enclosing the welding head and resting on the surface of the work piece, and means for passing a stream of protective gas through the shield to flood the upper portion of the gap in the work piece.
Claim 2
Dependent Claim
241 words
In narrow groove welding the combination comprising a work piece having a narrow groove therein with substanTially parallel walls and a groove width substantially less than the depth thereof, an electric welding machine positioned exteriorly of the work piece and having a welding head projecting into the groove, means for positioning the welding head in a direction parallel to the depth of the groove, means for controlled relative movement of the work piece and the electric welding machine parallel to the narrow groove, means for feeding a consumable electrode wire through the welding head into the groove, means for applying electric power through the consumable electrode wire to form an arc between the end of the wire and the work piece to weld join walls of the groove whereby the weld metal fuses both sides of the groove equally in a single pass, control means for regulating the rate of electrode wire feed to the arc, means for maintaining the tip of the electrode wire centered in the groove by transverse movement of the welding head relative to the walls of the groove, means for passing a protecting gas through the welding head to surround the welding arc in the groove, a shield loosely enclosing the welding head and resting on the surface of the work piece, and means for passing a stream of protective gas through the shield to flood the upper portion of the gap in the work piece.
Claim 3
Dependent Claim
15 words
The combination of claim 1 wherein the narrow groove is approximately 0.3 inch in width.
Claim 4
Dependent Claim
22 words
The combination of claim 1 wherein the work piece moves longitudinally of the groove relative to the position of the welding head.
Claim 5
Dependent Claim
39 words
The combination of claim 1 wherein transverse movement of the welding head is responsive to an indication of the deviation of the head from the opposite walls of the groove to maintain the wire tip centered in the groove.
Claim 6
Dependent Claim
21 words
The combination of claim 4 wherein eddy current sensors positioned in the frame detect deviation from the midpoint of the groove.
Claim 7
Dependent Claim
18 words
The combination of claim 5 wherein means actuated by the sensors shift the transverse position of the head.
Claim 8
Dependent Claim
20 words
The combination of claim 1 wherein the protective gas consists essentially of a mixture of helium, argon and carbon dixoide.
Claim 9
Dependent Claim
32 words
The combination of claim 7 wherein the helium content is between 70 and 75 percent, the argon content is between 19 and 24 percent and the CO2 content is approximately 6 percent.
Claim 10
Dependent Claim
18 words
The combination of claim 8 wherein the preferred gas mix is 70 He, 24A and 6 percent CO2.
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) | 1978-12-01 | 1979-06-02 | 1979-12-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-12-01 | 1983-06-02 | 1983-12-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-12-01 | 1987-06-02 | 1987-12-02 | $7700.00 | Window Closed / Lapsed |