US3686732A
Expired / Lapsed
US
⏱️ 0.0 years remaining
The method of making a positive choke device
Assignee: Materials Technology Corp
•
Filing: 1970-05-11
•
Granted: 1972-08-29
•
Expires: 1990-05-11
Abstract
Abstract Disclosed is a positive choke device having bore liner of silicon carbide. Also disclosed is a method of fabricating flow beans and the like having bore coatings of corrosion resistant materials having a hardness of at least 2,700 on the Knoop scale without machining of hard materials.
Inventors
- 👤 James H Mcclure
- 👤 James W Mccrary
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 10:45
CPC Classifications
C; C04; C04B; C04B35/00; C04B35/515; C04B35/52; C04B35/522; C04B35/56; C04B35/565; C23; C23C; C23C16/00; C23C16/01; F; F16; F16L; F16L55/00; F16L55/02; F16L55/027; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49405; Y10T29/49412
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
34 words
The method set forth in claim 1 wherein said coating of silicon carbide is deposited on said graphite rod by reacting a hydrocarbon and a silicon halide on the surface of said graphite rod.
Claim 2
Dependent Claim
19 words
The method set forth in claim 2 wherein said hydrocarbon is toluene and said silicon halide is silicon tetrachloride.
Claim 3
Dependent Claim
26 words
The method set forth in claim 3 wherein said silicon tetrachloride and said toluene are entrained in a hydrogen stream in a ratio of approximately 7:1.
Claim 4
Dependent Claim
49 words
The method set forth in claim 1 wherein said graphite rod is removed from said silicon carbide coating by boring a hole axially through the center of said graphite rod and dissolving the remaining graphite in a solution comprising about 1 part HNO3 and 9 parts H2SO4 by volume.
References Cited (Backward Citations)
US2640503A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-08-29 | 1976-02-28 | 1976-08-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-08-29 | 1980-02-28 | 1980-08-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-08-29 | 1984-02-28 | 1984-08-29 | $7700.00 | Window Closed / Lapsed |