US4727907A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Turbulator with integral flow deflector tabs
Assignee: Dunham Bush Inc
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Filing: 1987-03-30
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Granted: 1988-03-01
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Expires: 2007-03-30
Abstract
Abstract A turbulator for insertion in a heat exchange pipe in the form of a flattened hollow cylindrical metal tube with adjacent flats offset by 90° and separated by integral tubular transition portions of generally triangular plane configuration. An elongated tab is partially struck out of each flat forming a fluid passage hole leading from one side of the turbulator to the other side.
Inventors
- 👤 Donald C. Duncan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 19:13
CPC Classifications
F; F28; F28F; F28F13/00; F28F13/06; F28F13/12; F28D; F28D21/00; F28D2021/0019; F28D2021/008; F28D2021/0089
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
102 words
An improved turbulator for insertion in a heat exchanger pipe having a substantially straight longitudinal internal wall, said turbulator comprising: a cylindrical metal tube being flattened at longitudinally spaced positions along said tube to form flats offset circumferentially by 90°, and hollow tubular transition portions of said tube connecting said flats together said transition portions being of generally triangular shape in plan configuration, and an elongated tab partially struck out of each flat at an acute angle to the plane of the flat and defining a fluid passage hole within each flat leading from one side of the turbulator to the other.
Claim 2
Dependent Claim
102 words
An improved turbulator for insertion in a heat exchanger pipe having a substantially straight longitudinal internal wall, said turbulator comprising: a cylindrical metal tube being flattened at longitudinally spaced positions along said tube to form flats offset circumferentially by 90°, and hollow tubular transition portions of said tube connecting said flats together said transition portions being of generally triangular shape in plan configuration, and an elongated tab partially struck out of each flat at an acute angle to the plane of the flat and defining a fluid passage hole within each flat leading from one side of the turbulator to the other.
Claim 3
Dependent Claim
23 words
The turbulator as claimed in claim 1 wherein, alternating flats are co-planer, and have tabs projecting obliquely to opposite sides of said tube.
Claim 4
Dependent Claim
18 words
The turbulator as claimed in claim 1 wherein said tabs have free ends pointing in the same direction.
Claim 5
Dependent Claim
18 words
The turbulator as claimed in claim 2 wherein said tabs have free ends pointing in the same direction.
Claim 6
Dependent Claim
28 words
The turbulator as claimed in claim 3 wherein said tabs have side edges which taper toward each other in the direction of the free end of the tab.
Claim 7
Dependent Claim
29 words
The turbulator as claimed in claim 1 wherein said flats are of a length which are in excess of the length of each hollow transition portion joining adjacent flats.
Claim 8
Dependent Claim
45 words
The turbulator as claimed in claim 1 wherein, said tabs are of a length, and are at an oblique angle such that the free ends of the tab extend radially beyond the diameter of the turbulator proper as defined by the width of said flats.
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) | 1991-03-01 | 1991-08-31 | 1992-03-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-03-01 | 1995-08-31 | 1996-03-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-03-01 | 1999-08-31 | 2000-03-01 | $7700.00 | Window Closed / Lapsed |