Patent US4365136A successfully refreshed from Google Patents.
US4365136A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Zone refinement of inertia welded tubulars to impart improved corrosion resistance
Assignee: Hydril LLC
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Filing: 1981-02-23
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Granted: 1982-12-21
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Expires: 2001-02-23
Abstract
Abstract Corrosion resistance of tubular metal products is enhanced, and particularly to welds formed between metal tubes or pipes and threaded ends.
Inventors
- 👤 Theodore Gottlieb
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 16:47
CPC Classifications
C; C21; C21D; C21D9/00; C21D9/50; B; B23; B23K; B23K26/00; B23K26/08; B23K26/0823
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
84 words
In the method of fabricating an oil or gas well metallic tubular product, the steps that include, (a) providing a steel tube and a pre-fabricated thread end and welding said thread end to the tube to form a weld, (b) directing a laser beam at the surface of said weld to cause the beam to progressively and locally vaporize a thin film of the weld metal, and allowing the metal vapor to condense back onto the weld, thereby to form a corrosion resistant surface.
Claim 2
Dependent Claim
84 words
In the method of fabricating an oil or gas well metallic tubular product, the steps that include, (a) providing a steel tube and a pre-fabricated thread end and welding said thread end to the tube to form a weld, (b) directing a laser beam at the surface of said weld to cause the beam to progressively and locally vaporize a thin film of the weld metal, and allowing the metal vapor to condense back onto the weld, thereby to form a corrosion resistant surface.
Claim 3
Dependent Claim
17 words
The method of claim 1 including providing an inert gas environment wherein said local vaporization takes place.
Claim 4
Dependent Claim
19 words
The method of claim 2 wherein said inert gas is selected from the group that includes argon and helium.
Claim 5
Dependent Claim
28 words
The method of claim 1 including the step of relatively moving the beam and tube to extend said corrosion resistant surface over a substantial portion of the weld.
Claim 6
Dependent Claim
17 words
The method of claim 4 wherein said relative movement includes rotating the tube relative to the beam.
Claim 7
Dependent Claim
50 words
The method of claim 5 wherein said weld extends annularly, and said relative movement of the beam and tube includes relatively axially advancing the beam as the tube is relatively rotated, so that the beam progressively impinges on substantially all of the weld annular surface, and adjoining heat affected zones.
Claim 8
Dependent Claim
83 words
The method of claim 1 wherein the weld is annular and has an outer surface at the outwardly exposed outer side of said tubular product and an inner surface at the inwardly exposed inner side of the tube, said (b) step including; (i) directing a first laser beam at said outer surface of the weld to produce a corrosion resistant outer surface, and (ii) directing a second laser beam at said inner surface of the weld to produce a corrosion resistant inner surface.
Claim 9
Dependent Claim
42 words
The method of claim 7 wherein said inner and outer weld surfaces are annular, and including the step of relatively moving the beams and tube to extend said corrosion resistant surfaces over substantial portion of the weld inner and outer exposed surfaces.
Claim 10
Dependent Claim
17 words
The method of claim 8 wherein said relative movement includes rotating the tube relative to said beams.
Claim 11
Dependent Claim
42 words
The method of claim 9 wherein said relative movement of the beams and tube includes advancing the beams relatively axially of the tube as the tube is relatively rotated, so that the beams impinge on substantially all of the weld annular surface.
Claim 12
Dependent Claim
26 words
The method of claim 10 wherein said advancement is carried out to cause the beams to treat metallic surfaces adjacent the weld, at opposite ends thereof.
Claim 13
Dependent Claim
12 words
The method of claim 10 wherein said beams are advanced in unison.
Claim 14
Dependent Claim
19 words
The method of claim 10 wherein the beams are directed into substantial alignment as they impinge on the weld.
Claim 15
Dependent Claim
22 words
The method of claim 1 including the preliminary steps of stress relieving the tube at the region thereof which encompasses the weld.
Claim 16
Dependent Claim
23 words
The method of claim 14 including the step of machining the tube at the region thereof proximate the weld to remove weld flash.
Claim 17
Dependent Claim
71 words
In the method of fabricating an oil or gas well metallic tubular product, the steps that include, (a) providing a steel tube and a pre-fabricated thread end and welding said thread end to the tube to define a weld, (b) effecting progressive and local vaporization of a thin film of the weld metal, and allowing the metal vapor to condense back onto the weld, thereby to form a corrosion resistant surface.
Claim 18
Dependent Claim
71 words
In the method of fabricating an oil or gas well metallic tubular product, the steps that include, (a) providing a steel tube and a pre-fabricated thread end and welding said thread end to the tube to define a weld, (b) effecting progressive and local vaporization of a thin film of the weld metal, and allowing the metal vapor to condense back onto the weld, thereby to form a corrosion resistant surface.
Claim 19
Dependent Claim
80 words
In apparatus for the fabrication of our oil or gas well metallic tubular product, the combination comprising (a) means to support a steel tube to which a threaded end has been welded, and (b) means for directing a laser beam at the surface of said weld to cause the beam to progressively and locally vaporize a thin film of the weld metal, and allowing the metal vapor to condense back onto the weld, thereby to form a corrosion resistant surface.
Claim 20
Dependent Claim
80 words
In apparatus for the fabrication of our oil or gas well metallic tubular product, the combination comprising (a) means to support a steel tube to which a threaded end has been welded, and (b) means for directing a laser beam at the surface of said weld to cause the beam to progressively and locally vaporize a thin film of the weld metal, and allowing the metal vapor to condense back onto the weld, thereby to form a corrosion resistant surface.
Claim 21
Dependent Claim
26 words
The combination of claim 17 including a chamber defining a zone containing said weld during said metal surface vaporization, and an inert gas in said zone.
Claim 22
Dependent Claim
23 words
The combination of claim 17 wherein said (b) means includes a laser and a carriage therefor which is movable relative to said tubing.
Claim 23
Dependent Claim
31 words
The combination of claim 17 wherein said (b) means includes two lasers and carriage structure therefor, the lasers directing beams at inner and outer surfaces of said weld which is annular.
References Cited (Backward Citations)
CA838816A
Cited
US3250842A
Cited
US3769117A
Cited
US4000392A
Cited
US4017708A
Cited
US4063063A
Cited
US4122240A
Cited
US4080525A
Cited
US4129771A
Cited
JPS5337125A
Cited
US4229235A
Cited
US4247037A
Cited
US4239556A
Cited
JPS55117583A
Cited
JPS55126368A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-12-20 | 1986-06-21 | 1986-12-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-12-20 | 1990-06-21 | 1990-12-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-12-20 | 1994-06-21 | 1994-12-21 | $7700.00 | Window Closed / Lapsed |