US4132343A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for manufacturing a pipeline having an internal protective layer
Assignee: BBC Brown Boveri AG Switzerland
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Filing: 1977-03-01
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Granted: 1979-01-02
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Expires: 1997-03-01
Abstract
Abstract A pipeline consisting of lengths of steel pipe welded together in end-to-end relation is made by first weld-plating the internal surface of the end portions of each individual pipe length with a corrosion-resistant material. A protective layer is then applied to the internal surface of each pipe length between the weld-plated end portions, the latter having first been smoothed down by machining to the desired finished thickness of the protective layer. The pipe lengths are then welded together in end-to-end relation. The welding operation consists of first depositing a root bead encircling the pipe at the junction of the ends of the weld-plated material. Weld material is then deposited in and fills out the gap between bevelled edges of the pipe ends to substantially the outside diameter of the pipe.
Inventors
- 👤 Anders Kullendorff
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 05:43
CPC Classifications
F; F16; F16L; F16L13/00; F16L13/02; F16L13/0254; F16L13/0263; B; B23; B23K; B23K9/00; B23K9/23
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
141 words
A method for manufacturing a pipeline from lengths of steel pipe welded together in end-to-end relation to be used, for example, for the transmission of wet steam, comprising the steps of: weld-plating the internal end portions of adjoining pipe lengths with a layer of corrosion-resistant material, applying a protective layer of a particular thickness of a material resistant to erosion and corrosion to the internal surfaces of said pipe lengths between the weld-plated layers, providing a ring gap at the ends of adjoining pipe lengths when the ends are arranged closely adjacent to one another, applying a root bead of substantially the same material as is used for the weld-plated layer around the adjoining pipe ends at the junction ends of the weld-plated layer, and filling out the ring gap formed between adjoining edges of the pipe ends with welding material.
Claim 2
Independent Claim
141 words
A method for manufacturing a pipeline from lengths of steel pipe welded together in end-to-end relation to be used, for example, for the transmission of wet steam, comprising the steps of: weld-plating the internal end portions of adjoining pipe lengths with a layer of corrosion-resistant material, applying a protective layer of a particular thickness of a material resistant to erosion and corrosion to the internal surfaces of said pipe lengths between the weld-plated layers, providing a ring gap at the ends of adjoining pipe lengths when the ends are arranged closely adjacent to one another, applying a root bead of substantially the same material as is used for the weld-plated layer around the adjoining pipe ends at the junction ends of the weld-plated layer, and filling out the ring gap formed between adjoining edges of the pipe ends with welding material.
Claim 3
Dependent Claim
42 words
The method as defined in claim 1 for manufacturing a pipeline from steel pipe lengths welded together in end-to-end relation and which includes the further step of machining down the weld-plated layer to a thickness substantially identical to the protective layer thickness.
Claim 4
Dependent Claim
39 words
The method as defined in claim 1 for manufacturing a pipeline from pipe lengths of carbon tool steel welded together in end-to-end relation and wherein austenitic corrosion-resistant steel is used for said weld-plated layers and for said root beads.
Claim 5
Dependent Claim
44 words
The method as defined in claim 1 for manufacturing a pipeline from pipe lengths welded together in end-to-end relation and which includes the further step of weld-plating the seam surfaces of the pipe ends prior to the step of welding the pipe lengths together.
Claim 6
Dependent Claim
24 words
The method as defined in claim 1 wherein said ring gap is formed by providing beveled edges for the ends of adjoining pipe lengths.
Claim 7
Independent Claim
158 words
A method of joining together end portions of two lengths of steel pipe in an end-to-end relation for use, for example, to transmit wet steam, comprising the steps of: weld plating an internal end portion of each of the two lengths of steel pipe adjacent to the weld-plated layer; applying a protective layer of a particular thickness of a material resistant to erosion and corrosion to an internal surface of each of the two lengths of steel pipe adjacent to the weld-plated layer; forming a ring gap between the end portions of the two lengths of steel pipe by arranging the end portions closely adjacent to one another; applying a root bead of substantially the same material as is used for the weld-plated layer around the adjoining pipe ends at a junction between the weld plated layers of the closely adjacent end portions; filling out the ring gap formed between the closely adjacent end portions with welding material.
Claim 8
Independent Claim
158 words
A method of joining together end portions of two lengths of steel pipe in an end-to-end relation for use, for example, to transmit wet steam, comprising the steps of: weld plating an internal end portion of each of the two lengths of steel pipe adjacent to the weld-plated layer; applying a protective layer of a particular thickness of a material resistant to erosion and corrosion to an internal surface of each of the two lengths of steel pipe adjacent to the weld-plated layer; forming a ring gap between the end portions of the two lengths of steel pipe by arranging the end portions closely adjacent to one another; applying a root bead of substantially the same material as is used for the weld-plated layer around the adjoining pipe ends at a junction between the weld plated layers of the closely adjacent end portions; filling out the ring gap formed between the closely adjacent end portions with welding material.
Claim 9
Dependent Claim
23 words
The method of claim 6 wherein the weld-plated layer is machined to a thickness which is substantially identical to the protective layer thickness.
Claim 10
Dependent Claim
30 words
The method of claim 6 wherein the steel pipe is formed of carbon tool steel and wherein the root bead and the weld-plated layers are formed of austenitic corrosion-resistant steel.
Claim 11
Dependent Claim
26 words
The method of claim 6 wherein the internal end portions of the two lengths of steel pipe are weld-plated before the ring gap is filled out.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-01-01 | 1982-07-03 | 1983-01-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-01-01 | 1986-07-03 | 1987-01-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-01-01 | 1990-07-03 | 1991-01-02 | $7700.00 | Window Closed / Lapsed |