Patent US4256995A successfully refreshed from Google Patents.
US4156533A
Expired / Lapsed
US
⏱️ 0.0 years remaining
High temperature gasket
Assignee: 3M Co
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Filing: 1978-04-28
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Granted: 1979-05-29
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Expires: 1998-04-28
Abstract
Abstract Gasketing material is produced by combining a tubular casing of braided or woven from continuous inorganic filaments, such as alumina-boria-silica fibers, with a core composition comprising a major proportions of intumescent material, suitably unexpanded vermiculite. Heating the gasket in situ results in expansion to give a resilient gasket stable to temperatures of about 1000° to 1200° C.
Inventors
- 👤 James R. Close
- 👤 Lance W. Pihlstrom
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 07:34
CPC Classifications
F; F01; F01N; F01N3/00; F01N3/08; F01N3/10; F01N3/24; F01N3/28; F01N3/2839; F01N3/2853; F01N3/2864; F01N3/2857; F16; F16J; F16J15/00; F16J15/02; F16J15/06; F16J15/064; F16J15/065; Y; Y10; Y10S; Y10S277/00; Y10S277/931; Y10S277/933; Y10S428/00; Y10S428/92; Y10S428/921; Y10T; Y10T428/00; Y10T428/23; Y10T428/233; Y10T428/237
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
111 words
A composite gasketing material comprising, in combination, outer sheathing means of continuous inorganic filaments and having cross-sectionally a central free space, equilong intumescent core means within said sheathing means at least partially filling said central free space of said sheathing means and expandable to fill said free space of said sheathing means, said intumescent core means being a composition comprising, in percentages by weight of dry material, about 30 to about 80% of an expandable inorganic fibrous material, about 5 to about 60% inorganic reinforcing agents, 0 to about 55% of fillers and about 10 to about 70% of organic and inorganic binders in combination in ratios of 1:2 to 5:1.
Claim 2
Dependent Claim
111 words
A composite gasketing material comprising, in combination, outer sheathing means of continuous inorganic filaments and having cross-sectionally a central free space, equilong intumescent core means within said sheathing means at least partially filling said central free space of said sheathing means and expandable to fill said free space of said sheathing means, said intumescent core means being a composition comprising, in percentages by weight of dry material, about 30 to about 80% of an expandable inorganic fibrous material, about 5 to about 60% inorganic reinforcing agents, 0 to about 55% of fillers and about 10 to about 70% of organic and inorganic binders in combination in ratios of 1:2 to 5:1.
Claim 3
Dependent Claim
40 words
A composite gasketing material according to claim 1 wherein the expandable inorganic material of the intumescent core means is unexpanded vermiculite, hydrobiotite, water-swelling synthetic tetrasilicic fluorine-type mica or hydrous alkali metal silicate containing about 3 to 20% by weight water.
Claim 4
Dependent Claim
21 words
Composite gasketing material according to claim 2 wherein the sheathing means is braided or woven tube or piping of silica-containing filaments.
Claim 5
Dependent Claim
35 words
Composite gasketing material according to claim 1 in annular form with ends of outer sheathing means abutting to form a joining and with ends of core means substantially offset from ends of outer sheathing means.
Claim 6
Dependent Claim
28 words
Composite gasketing material according to claim 4 comprising additionally sheathing overlapping said joining of the ends of the sheathing means and extending on either side of said joining.
Claim 7
Dependent Claim
18 words
Composite gasketing material according to claim 1 additionally comprising external shielding means composed of metallic sheet or foil.
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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) | 1982-05-28 | 1982-11-27 | 1983-05-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-05-28 | 1986-11-27 | 1987-05-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-05-28 | 1990-11-27 | 1991-05-29 | $7700.00 | Window Closed / Lapsed |