US3849871A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for welding pipes
Assignee: Individual
•
Filing: 1973-08-06
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Granted: 1974-11-26
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Expires: 1993-08-06
Abstract
Abstract A method for welding large tubular members such as pipe in endto-end relationship by first machining the ends of the members to form a radially thin, axially extending flange on each end adjacent the interior surface of the member; co-axially aligning the members so that the flanges formed on the ends to be joined are aligned in closely spaced relationship; heating the ends to be joined and particularly, the flanges formed on each end while, at the same time, purging the free oxygen from the space surrounding the adjoining ends of the members by means of inert gas; forcing the heated ends together with sufficient force to upset the radially thin, axially extending flanges and fuse the metal of each flange together to form a root joint which securely joins the two members; smoothing the surface of the root joint about the periphery of the joined members; and, filling the groove formed by the facing ends of the members and the root joint with welding metal to complete and form a perfectly sealed fluid tight joint between the members.
Inventors
- 👤 C Kaunitz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 16:29
CPC Classifications
B; B23; B23K; B23K28/00; B23K28/02; B23K13/00; B23K9/00; B23K9/02; B23K9/028; B23K9/0282
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
214 words
A method for securely and fluid tightly joining a pair of generally tubular members in end-to-end relationship, characterized by the steps of: forming an axially extending root portion on an end of each tubular member having a lesser radial dimension than the radial thickness of the wall of each tubular member, to provide a peripheral welding groove when said members are brought into abutting co-axial relationship; co-axially aligning said tubular members so that the ends of each of said tubular members having said axially extending root portions formed thereon are disposed in closely spaced relationship opposite and facing one another; heating said closely spaced ends of said tubular members having said axially extending root portions to a sufficiently high temperature such that said root portions may be welded together; forcing said tubular members axially toward one another to bring said axially extending root portions into intimate, abutting relationship with sufficient force to upset said root portions and weld these root portions together to form a solid and perfectly sealed root joint which joins said tubular members together; and, applying weld metal in said welding groove formed by said root joint and said facing ends of said tubular members sufficient to fill said groove and completely form and seal the joint between said tubular members.
Claim 2
Independent Claim
214 words
A method for securely and fluid tightly joining a pair of generally tubular members in end-to-end relationship, characterized by the steps of: forming an axially extending root portion on an end of each tubular member having a lesser radial dimension than the radial thickness of the wall of each tubular member, to provide a peripheral welding groove when said members are brought into abutting co-axial relationship; co-axially aligning said tubular members so that the ends of each of said tubular members having said axially extending root portions formed thereon are disposed in closely spaced relationship opposite and facing one another; heating said closely spaced ends of said tubular members having said axially extending root portions to a sufficiently high temperature such that said root portions may be welded together; forcing said tubular members axially toward one another to bring said axially extending root portions into intimate, abutting relationship with sufficient force to upset said root portions and weld these root portions together to form a solid and perfectly sealed root joint which joins said tubular members together; and, applying weld metal in said welding groove formed by said root joint and said facing ends of said tubular members sufficient to fill said groove and completely form and seal the joint between said tubular members.
Claim 3
Dependent Claim
50 words
The method set forth in claim 1 including the step of smoothing at least the outer radial surface of said root joint which forms the bottom of said welding groove prior to applying said weld metal to fill said groove to remove metal burrs and thereby enhance the weld bond.
Claim 4
Dependent Claim
54 words
The method set forth in claim 1 including purging the interior and exterior of said tubular members about the ends of said members having said root portions with an inert gas while heating said ends to prevent oxidation during welding thereby to assist in preventing microcracking and improve the appearance of the joint formed.
Claim 5
Dependent Claim
36 words
The method set forth in claim 1 wherein heating is accomplished by means of induction coils placed adjacent the joint area formed by the spaced ends of said tubular members having said axially extending root portions.
Claim 6
Dependent Claim
46 words
The method set forth in claim 1 wherein clamping means exert a radial force on the wall of each member equal to approximately 1 1/2 times the axial force exerted on each of said members in forcing them together to upset said axially extending root portions.
Claim 7
Dependent Claim
41 words
The method set forth in claim 5 wherein both said radial force and said axial upset force are applied to each of said tubular members by clamping means positioned relative to each of said members to frictionally engage the wall thereof.
Claim 8
Dependent Claim
28 words
The method set forth in claim 1 wherein said axially extending root portions are formed by machining the ends of said tubular members which are to be joined.
Claim 9
Dependent Claim
68 words
The method set forth in claim 7 wherein the ends of the walls of said tubular members are machined to form a radially thin root portion which projects axially from the end of the wall of each tubular member to form a land having generally parallel top and bottom surfaces and an outer face shaped to assure a full weld pattern without inward expulsion of material during upset.
Claim 10
Dependent Claim
28 words
The method set forth in claim 1 wherein said axially extending root portion is formed adjacent the inside surface of the wall of each of said tubular members.
Claim 11
Independent Claim
254 words
A method for securely and fluid tightly joining two generally tubular members in end-to-end relationship, characterized by the steps of: machining the ends of each of said tubular members to form a radially thin, axially extending root portion on the end of each of saiD members, said root portions providing a peripheral welding groove when said tubular members are brought together in abutting relationship; co-axially aligning said tubular members so that the ends of each tubular member having axially extending root portions formed thereon are disposed in closely spaced relationship opposite and facing one another; heating said closely spaced ends of said tubular members having said axially extending root portions to a sufficiently high temperature such that said axially extending root portions may be welded together; purging the space about the ends of said tubular members having said root portions with an inert gas while heating said ends, to prevent oxidation during welding thereby assisting in preventing microcracking; forcing said tubular members axially toward one another to bring said axially extending root portions into intimate, abutting relationship with sufficient force to upset said axially extending root portions and thereby weld these root portions together to form a solid and perfectly sealed root joint which joins the tubular members together; and, applying sufficient layers of weld metal in said welding groove formed by said root joint and the opposite ends of said tubular members over said root joint to fill said welding groove and thereby completely form the joint which seals said tubular members together.
Claim 12
Independent Claim
254 words
A method for securely and fluid tightly joining two generally tubular members in end-to-end relationship, characterized by the steps of: machining the ends of each of said tubular members to form a radially thin, axially extending root portion on the end of each of saiD members, said root portions providing a peripheral welding groove when said tubular members are brought together in abutting relationship; co-axially aligning said tubular members so that the ends of each tubular member having axially extending root portions formed thereon are disposed in closely spaced relationship opposite and facing one another; heating said closely spaced ends of said tubular members having said axially extending root portions to a sufficiently high temperature such that said axially extending root portions may be welded together; purging the space about the ends of said tubular members having said root portions with an inert gas while heating said ends, to prevent oxidation during welding thereby assisting in preventing microcracking; forcing said tubular members axially toward one another to bring said axially extending root portions into intimate, abutting relationship with sufficient force to upset said axially extending root portions and thereby weld these root portions together to form a solid and perfectly sealed root joint which joins the tubular members together; and, applying sufficient layers of weld metal in said welding groove formed by said root joint and the opposite ends of said tubular members over said root joint to fill said welding groove and thereby completely form the joint which seals said tubular members together.
Claim 13
Dependent Claim
36 words
The method set forth in claim 10 wherein heating is accomplished by means of induction coils placed adjacent the joint area formed by the spaced ends of said tubular members having said axially extending root portions.
Claim 14
Dependent Claim
46 words
The method set forth in claim 10 wherein clamping means exert a radial force on the wall of each member equal to apporximately 1 1/2 times the axial force exerted on each of said members in forcing them together to upset said axially extending root portions.
Claim 15
Dependent Claim
78 words
The method set forth in claim 10 wherein the ends of the walls of said tubular members are machined to form a radially thin root portion which projects from the end of the wall of each tubular member adjacent the interior surface of the wall of said tubular member to form a land having generally parallel top and bottom surfaces and an outer face shaped to assure a full weld pattern without inward expulsion of material during upset.
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) | 1977-11-25 | 1978-05-27 | 1978-11-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-11-25 | 1982-05-27 | 1982-11-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-11-25 | 1986-05-27 | 1986-11-26 | $7700.00 | Window Closed / Lapsed |