Patent US2443448A successfully refreshed from Google Patents.
US3671386A
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Producing tubular members of lignocellulose material by compression within an annular chamber
Assignee: Platmanufaktur AB
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Filing: 1969-12-03
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Granted: 1972-06-20
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Expires: 1989-12-03
Abstract
Abstract A METHOD AND APPARATUS FOR MAKING TUBULAR MEMBERS WHEREIN A SLURRY OF A LIQUID AND A LIGNOCELLULOSE MATERIAL IS RECIPROCATINGLY COMPRESSED IN A VERTICALLY ALIGNED DEWATERING CHAMBER OF ANNULAR CROSS-SECTION. THE COMPRESSION TAKES PLACE IN A VERTICAL DIRECTION AND THE DRAINAGE OPPENINGS ARE ANGLED SUCH THAT THE EXTRACTED LIQUID DOES NOT REPASS THROUGH THE TUBULAR MEMBER BEING FORMED. THE TUBULAR PRODUCT IS THEN PLACED IN A MOULD WHERE IT UNDERGOES RADIAL COMPRESSION AT A PRESSURE OF FROM 10 TO 100 ATMOSPHERES AND IS HEATED TO A TEMPERATURE OF 50 TO 250*C. TO THERMOSET THE LIGNOCELLULOSE MATERIAL.
Inventors
- 👤 Kjell Moswoll Jakobsen
- 👤 Hans-Ivar Eriksson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 15:47
CPC Classifications
D; D21; D21J; D21J3/00
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-06-20 | 1975-12-20 | 1976-06-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-06-20 | 1979-12-20 | 1980-06-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-06-20 | 1983-12-20 | 1984-06-20 | $7700.00 | Window Closed / Lapsed |