Patent US4807504A successfully refreshed from Google Patents.
US4275784A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Fail safe heat exchanger
Assignee: Olin Corp
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Filing: 1980-03-31
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Granted: 1981-06-30
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Expires: 2000-03-31
Abstract
Abstract A multiple passage metal heat exchanger is disclosed which contains a metal barrier between sets of passageways. The barrier is cathodic to the metal of the heat exchanger and prevents intermixing of different heat transfer fluids due to corrosion.
Inventors
- 👤 James M. Popplewell
- 👤 Sheldon H. Butt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 14:51
CPC Classifications
F; F28; F28F; F28F3/00; F28F3/12; F28F3/14; F28F19/00; F28F19/004; Y; Y10; Y10T; Y10T428/00; Y10T428/12; Y10T428/12493; Y10T428/12771; Y10T428/12861; Y10T428/12903; Y10T428/1291
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
102 words
A composite fail safe metal heat exchanger comprising: an inner metal tube comprising copper or a copper alloy forming a fluid passageway; an outer metal tube comprising copper or a copper alloy; said inner and outer tubes being concentric; a substantially continuous corrosion barrier; said corrosion barrier comprising nickel or a nickel alloy which is noble to the metal of said inner and outer tubes; said corrosion barrier being located between and in intimate contact with said inner and outer tubes; whereby said corrosion barrier is adapted to prevent intermixing between a fluid within said passageway with fluid surrounding said outer tube.
Claim 2
Dependent Claim
102 words
A composite fail safe metal heat exchanger comprising: an inner metal tube comprising copper or a copper alloy forming a fluid passageway; an outer metal tube comprising copper or a copper alloy; said inner and outer tubes being concentric; a substantially continuous corrosion barrier; said corrosion barrier comprising nickel or a nickel alloy which is noble to the metal of said inner and outer tubes; said corrosion barrier being located between and in intimate contact with said inner and outer tubes; whereby said corrosion barrier is adapted to prevent intermixing between a fluid within said passageway with fluid surrounding said outer tube.
Claim 3
Dependent Claim
23 words
The heat exchanger of claim 1 wherein said tubes and said corrosion barrier are metallurgically bonded together to form said composite heat exchanger.
Claim 4
Dependent Claim
32 words
The heat exchanger of claim 1 wherein said tubes are diffusion bonded to said corrosion barrier whereby a diffusion zone exists at the interface of each said tube and said corrosion barrier.
Claim 5
Dependent Claim
14 words
The heat exchanger of claim 3 wherein said diffusion zone comprises copper nickel alloy.
Claim 6
Dependent Claim
26 words
The heat exchanger of claim 1 wherein said inner and outer tubes and said corrosion barrier are mechanically fastened together to form said composite heat exchanger.
Claim 7
Dependent Claim
14 words
The heat exchanger of claim 1 wherein said corrosion barrier comprises a metallic sheet.
Claim 8
Dependent Claim
14 words
The heat exchanger of claim 1 wherein said corrosion barrier comprises a nickel foil.
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) | 1984-06-29 | 1984-12-29 | 1985-06-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-06-29 | 1988-12-29 | 1989-06-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-06-29 | 1992-12-29 | 1993-06-30 | $7700.00 | Window Closed / Lapsed |