US3513728A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for manufacturing apparatus useful in an abrasive environment
Assignee: Dresser Industries Inc
•
Filing: 1969-02-07
•
Granted: 1970-05-26
•
Expires: 1989-02-07
Abstract
No abstract record available.
Inventors
- 👤 Lester S Hudson
- 👤 Eugene G Ott
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 12:50
CPC Classifications
E; E21; E21B; E21B10/00; E21B10/08; E21B10/18; E21B10/46; E21B10/50; E21B10/52
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-05-25 | 1973-11-24 | 1974-05-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-05-25 | 1977-11-24 | 1978-05-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-05-25 | 1981-11-24 | 1982-05-26 | $7700.00 | Window Closed / Lapsed |