US4427034A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Coating composition for protecting inner surface of tubes in heat exchangers
Assignee: Sumitomo Light Metal Industries Ltd
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Filing: 1981-08-27
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Granted: 1984-01-24
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Expires: 2001-08-27
Abstract
Abstract Anti-corrosive coating composition mainly applied to the inner surface of a copper alloy made heat exchanger tube, employed in heat changers, of relatively small diameter and of large length. The composition is prepared by adding an aminoalkoxysilane compound or a combination of plural aminoalkoxysilane compounds at a ratio of 0.1-5% by weight to a film-forming coating composition constituting of as a base substance thereof an organic polymer resin selected from a group consisting of alkyl resin, vinyl resin, polyurethane resin, epoxy resin, and acrylic resin. The composition is preferably applied by means of spray coating method.
Inventors
- 👤 Koji Nagata
- 👤 Shiro Sato
- 👤 Akio Ogiso
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 14:05
CPC Classifications
F; F28; F28F; F28F19/00; F28F19/02; F28F19/04; C; C09; C09D; C09D5/00; C09D5/08; C09D5/082; C09D5/086; C08; C08K; C08K5/00; C08K5/54; C08K5/544; Y; Y10; Y10S; Y10S138/00; Y10S138/06; Y10S165/00; Y10S165/914
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
121 words
A heat exchanger tube having a small diameter in the order of 10-40 mm and a large length in the order of 3-40 m and provided on the inner surface with an artificial protective film less than 50μ in thickness, not more than 0.0001 m 2 h°C./Kcal in fouling factor and not less than 5000 Ω cm 2 in polarization resistance, said artificial protective film being formed by a spray coating of a coating composition prepared by adding at least one aminoalkoxysilane compound at a ratio of 0.1-5% by weight to a liquid coating composition including as a film-forming material at least one organic polymer resin selected from a group consisting of alkyd resin polyurethane resin, epoxy resin, and acrylic resin.
Claim 2
Dependent Claim
121 words
A heat exchanger tube having a small diameter in the order of 10-40 mm and a large length in the order of 3-40 m and provided on the inner surface with an artificial protective film less than 50μ in thickness, not more than 0.0001 m 2 h°C./Kcal in fouling factor and not less than 5000 Ω cm 2 in polarization resistance, said artificial protective film being formed by a spray coating of a coating composition prepared by adding at least one aminoalkoxysilane compound at a ratio of 0.1-5% by weight to a liquid coating composition including as a film-forming material at least one organic polymer resin selected from a group consisting of alkyd resin polyurethane resin, epoxy resin, and acrylic resin.
Claim 3
Dependent Claim
29 words
A heat exchanger tube as claimed in claim 1, wherein said aminoalkoxysilane compound is selected from a group consisting of aminomethyltrimethoxysilane, aminoethyltrimethoxysilane, aminopropyltrimethoxysilane, aminopropylmethyldimethoxysilane, aminopropyltriethoxysilane, aminopropyltripropoxysilane, N-aminoethyl-aminopropyltrimethoxysilane, and N-aminoethyl-aminopropylmethyldimethoxysilane.
Claim 4
Dependent Claim
26 words
A heat exchanger tube as claimed in claim 2, wherein said aminoalkoxysilane compound employed is a combination of more than one compound selected from said group.
Claim 5
Dependent Claim
26 words
A heat exchanger tube as claimed in claim 1, or claim 2, or claim 3, wherein said heat exchanger tube is made of a copper alloy.
Claim 6
Dependent Claim
35 words
A heat exchanger tube as claimed in claim 1, or claim 2, or claim 3, wherein said protective film comprises a thin film on the inner surface of said heat exchanger tube of uniform thickness.
Claim 7
Dependent Claim
22 words
A heat exchanger tube as claimed in claim 3, wherein the combination of said aminoalkoxysilane compounds is that of N-β-(aminoethyl)-γ-aminopropylmethyldimethoxysilane and γ-aminopropyltriethoxysilane.
Claim 8
Dependent Claim
23 words
A heat exchanger tube as claimed in claim 3, wherein the combination of said aminoalkoxysilane compounds is that of N-β-(aminoethyl)-γ-aminopropyltrimethoxysilane, N-β-(aminoethyl)-γ-aminopropylmethyldimethoxysilane and γ-aminopropyltriethoxysilane.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-01-23 | 1987-07-25 | 1988-01-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-01-23 | 1991-07-25 | 1992-01-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-01-23 | 1995-07-25 | 1996-01-24 | $7700.00 | Window Closed / Lapsed |