Patent US4457788A successfully refreshed from Google Patents.
US4457788A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Particulate medium for fluidized bed operations
Assignee: Allstate Financial Corp
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Filing: 1982-03-01
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Granted: 1984-07-03
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Expires: 2002-03-01
Abstract
Abstract This invention relates to non-abrasive, lubricative, particulate solids, e.g. graphites, lime, calcium oxides, zinc oxides and compounds of higher saturated fatty acids, particularly, stearate salts, and their methods of use as fluidized bed media for preventing clinging and related carryover problems. Preferably, fluidized bed media, selected in accordance with this invention, have a beneficial effect on subsequent process operations.
Inventors
- 👤 Herbert K. Staffin
- 👤 Robert Staffin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 12:03
CPC Classifications
F; F16; F16N; F16N15/00; B; B01; B01J; B01J8/00; B01J8/18; B01J8/1836; B01J8/24; B01J8/46; B01J2208/00; B01J2208/00008; B01J2208/00017; B01J2208/00106; B01J2208/00168; B01J2208/00212; B01J2208/0053
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
72 words
An improved thermal treating process in a metal processing operation which prepares a workpiece for subsequent processing operations wherein the improvement comprises: carrying out at least one thermal treatment operation on a workpiece in a fluidized bed having a particulate lubricative non-abrasive bed medium which eliminates abrasive damage to the workpiece, minimizes interference with subsequent process operations due to particles from the particulate medium clinging to the workpiece, and lubricates the workpiece.
Claim 2
Dependent Claim
72 words
An improved thermal treating process in a metal processing operation which prepares a workpiece for subsequent processing operations wherein the improvement comprises: carrying out at least one thermal treatment operation on a workpiece in a fluidized bed having a particulate lubricative non-abrasive bed medium which eliminates abrasive damage to the workpiece, minimizes interference with subsequent process operations due to particles from the particulate medium clinging to the workpiece, and lubricates the workpiece.
Claim 3
Dependent Claim
24 words
An improved thermal treating process as recited in claim 1 wherein the fluidized bed medium is selected from the group consisting of graphite compounds.
Claim 4
Dependent Claim
17 words
An improved thermal treating process as recited in claim 1 wherein the fluidized bed medium is graphite.
Claim 5
Dependent Claim
17 words
An improved thermal treating process as recited in claim 1 wherein the fluidized bed medium is lime.
Claim 6
Dependent Claim
18 words
An improved thermal treating process as recited in claim 1 wherein the fluidized bed medium is calcium oxide.
Claim 7
Dependent Claim
36 words
An improved thermal treating process as recited in any one of claims 1, 2, 3, 4, or 5 wherein the fluidized bed medium has a particle size substantially in the range of 20 to 240 mesh.
Claim 8
Dependent Claim
36 words
An improved thermal treating process as recited in any one of claims 1, 2, 3, 4, or 5 wherein the fluidized bed medium has a particle size substantially in the range of 60 to 150 mesh.
References Cited (Backward Citations)
US2519127A
Cited
US3197346A
Cited
US2870903A
Cited
US2767838A
Cited
US3085034A
Cited
US3760488A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-07-03 | 1988-01-02 | 1988-07-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-07-03 | 1992-01-02 | 1992-07-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-07-03 | 1996-01-02 | 1996-07-03 | $7700.00 | Window Closed / Lapsed |