US3580026A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for manufacturing finned pipes
Assignee: INST DE CERCETARI TEHNOLOGIC P
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Filing: 1968-12-17
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Granted: 1971-05-25
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Expires: 1988-12-17
Abstract
Abstract Cooling fins are rolled onto the outer surface of a pipe or tube, while simultaneously the cross section of the pipe or tube is changed to an oval or elliptical shape. The inner surface of the pipe or tube may be either smooth or provided with grooves. The fins are formed by three rotating dies, and the crosssectional shape and inner surface is formed by drawing the pipe or tube over a rotating mandrel.
Inventors
- 👤 Ioan Luca
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 22:12
CPC Classifications
B; B21; B21C; B21C37/00; B21C37/06; B21C37/15; B21C37/20; B21C37/207
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
51 words
A method for producing oval finned pipes or tubes, comprising the steps of: a. moving a pipe having smooth inner and outer surfaces over a rotating ovaling mandrel in rotating engagement therewith; and b. rolling fins on the outer surface of the pipe while it is being moved over said mandrel.
Claim 2
Independent Claim
51 words
A method for producing oval finned pipes or tubes, comprising the steps of: a. moving a pipe having smooth inner and outer surfaces over a rotating ovaling mandrel in rotating engagement therewith; and b. rolling fins on the outer surface of the pipe while it is being moved over said mandrel.
Claim 3
Dependent Claim
85 words
Apparatus for producing oval finned pipes and tubes from smooth walled pipes and tubes comprising, in combination: a. an axially fixed, rotating mandrel means over which a smooth walled pipe is drawn while being rotated with said mandrel means, said mandrel means being shaped to give the inner surface of said pipe its desired cross section; and b. rotating die means disposed so as to roll integral fins on the outer surface of the pipe while it is drawing the pipe over said mandrel means.
Claim 4
Dependent Claim
85 words
Apparatus for producing oval finned pipes and tubes from smooth walled pipes and tubes comprising, in combination: a. an axially fixed, rotating mandrel means over which a smooth walled pipe is drawn while being rotated with said mandrel means, said mandrel means being shaped to give the inner surface of said pipe its desired cross section; and b. rotating die means disposed so as to roll integral fins on the outer surface of the pipe while it is drawing the pipe over said mandrel means.
Claim 5
Dependent Claim
33 words
The apparatus as defined in claim 2 wherein said rotating die means includes three forming rolls rotating in the same direction, each of said forming rolls having a die element on its periphery.
Claim 6
Dependent Claim
33 words
The apparatus as defined in claim 3 wherein said mandrel has a cross-sectional shape which varies along its length so that the pipe is progressively shaped as it is drawn over said mandrel.
Claim 7
Dependent Claim
15 words
The apparatus as defined in claim 4 wherein said mandrel has a smooth outer surface.
Claim 8
Dependent Claim
15 words
The apparatus as defined in claim 4, wherein said mandrel has a grooved outer surface.
Claim 9
Dependent Claim
18 words
The apparatus as defined in claim 6 wherein said grooves are parallel to the axis of the pipe.
Claim 10
Dependent Claim
36 words
The apparatus as defined in claim 6 wherein said grooves are at an angle relative to the axis of the pipe, so that the grooves formed in the pipe wind around the axis of the pipe.
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) | 1974-05-24 | 1974-11-23 | 1975-05-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-05-24 | 1978-11-23 | 1979-05-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-05-24 | 1982-11-23 | 1983-05-25 | $7700.00 | Window Closed / Lapsed |