Patent US3789915A successfully refreshed from Google Patents.
US3789915A
Expired / Lapsed
US
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Process for improving heat transfer efficiency and improved heat transfer system
Assignee: Olin Corp
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Filing: 1971-04-23
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Granted: 1974-02-05
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Expires: 1991-04-23
Abstract
Abstract The instant disclosure teaches a process for improving heat transfer efficiency and an improved heat exchange system utilizing an improved highly corrosion resistant enhanced metal tubing consisting essentially of from 0.5 to 4.0 percent iron, balance essentially copper.
Inventors
- 👤 J Ford
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 16:25
CPC Classifications
F; F28; F28F; F28F21/00; F28F21/08; F28F21/081; F28F21/085; C; C22; C22C; C22C9/00; F28F1/00; F28F1/10
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
11 words
A process according to claim 1 wherein said tubing is corrugated.
Claim 2
Dependent Claim
29 words
A process according to claim 2 wherein said tubing is spirally corrugated and exhibits substantially no change in weight per unit length as uncorrugated tubing of the same composition.
Claim 3
Dependent Claim
11 words
A process according to claim 1 wherein said tubing is knurled.
Claim 4
Dependent Claim
19 words
A process according to claim 1 wherein said tubing contains phosphorus in an amount from 0.015 to 0.04 percent.
Claim 5
Dependent Claim
47 words
A process according to claim 5 wherein said tubing includes a material selected from the group consisting of the following elements in an amount from 0.01 to 1.0 percent by weight each: vanadium, chromium, molybdenum, silicon, tin, titanium, aluminum, arsenic, antimony, columbium, cobalt, tantalum and mixtures thereof.
Claim 6
Dependent Claim
18 words
A process according to claim 5 wherein said tubing includes zinc in an amount up to 0.30 percent.
Claim 7
Dependent Claim
12 words
A process according to claim 1 wherein said tubing is welded tubing.
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) | 1977-02-04 | 1977-08-06 | 1978-02-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-02-04 | 1981-08-06 | 1982-02-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-02-04 | 1985-08-06 | 1986-02-05 | $7700.00 | Window Closed / Lapsed |