Patent US4412558A successfully refreshed from Google Patents.
US4412558A
Expired / Lapsed
US
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Turbulator
Assignee: WESTERN FUEL REDUCERS Inc A CORP OF OREGON
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Filing: 1981-08-25
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Granted: 1983-11-01
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Expires: 2001-08-25
Abstract
Abstract A turbulator comprising a strip of metal formed into a generally zig-zag longitudinal extending element for insertion into a fire tube of a furnace which so deflects gases passing through the tube as to break up laminar flow and thus improve heat transfer. The apices at the junctures of the legs of the element, which contact the interior wall of the fire tube, are rounded both longitudinally and laterally of the length of the strip to insure non-scratch contact with the interior wall during insertion and retraction whereby to prolong the life of the tube by eliminating zones sensitive to corrosion.
Inventors
- 👤 Michael J. Burke
- 👤 Harry E. Fowler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 06:16
CPC Classifications
F; F28; F28F; F28F13/00; F28F13/06; F28F13/12
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
116 words
A turbulator comprising a strip bent into zig-zag form to provide two spaced essentially parallel series of apices for contact with the interior wall of a gas conducting tube, each apex being so formed as to present an outwardly facing convex surface including a central area of contact surrounded on all sides by areas of double curvature, the side edges of the strip at the apices being located closer to the midplane of the strip than are said central areas of contact, the height of the turbulator being a number of times greater than the width of the strip, said central areas of contact providing for each apex a single area of contact with the tube.
Claim 2
Dependent Claim
116 words
A turbulator comprising a strip bent into zig-zag form to provide two spaced essentially parallel series of apices for contact with the interior wall of a gas conducting tube, each apex being so formed as to present an outwardly facing convex surface including a central area of contact surrounded on all sides by areas of double curvature, the side edges of the strip at the apices being located closer to the midplane of the strip than are said central areas of contact, the height of the turbulator being a number of times greater than the width of the strip, said central areas of contact providing for each apex a single area of contact with the tube.
Claim 3
Dependent Claim
39 words
A turbulator as recited in claim 1 in which such outwardly facing convex surfaces are curved both longitudinally and laterally of the strip, with the lateral curvature being centered about an area intermediate the side edges of the strip.
Claim 4
Dependent Claim
38 words
A turbulator as recited in claim 2 in which the curvature laterally is on a radius less than that of the tube to space the side edges of the strip away from the interior wall of the tube.
Claim 5
Dependent Claim
24 words
A turbulator as recited in claim 2 in which the curvature laterally is on a radius less than one-half the height of the strip.
Claim 6
Dependent Claim
37 words
A turbulator as recited in claim 1, wherein said bent strip provides a series of legs juncturing at the apices of said strip, and wherein the legs are essentially flat in the portions thereof between said apices.
Claim 7
Dependent Claim
33 words
A turbulator as recited in claim 1 in which said outwardly facing convex surfaces are provided by a series of bronze caps secured one to each of the apices of the zig-zag strip.
References Cited (Backward Citations)
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Cited
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Cited
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Cited
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Cited
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Cited
US4269265A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-10-31 | 1987-05-02 | 1987-11-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-10-31 | 1991-05-02 | 1991-11-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-10-31 | 1995-05-02 | 1995-11-01 | $7700.00 | Window Closed / Lapsed |