US3673004A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of making piston rings
Assignee: INST CERETARI TEHNOLOGICE PENT
•
Filing: 1970-07-23
•
Granted: 1972-06-27
•
Expires: 1990-07-23
Abstract
Abstract A METHOD OF MAKING PISTON RINGS FOR INTERNAL-COMBUSTION ENGINES, EXTERNAL-COMBUSTION ENGINES SUCH AS STEAM ENGINES, AIR COMPRESSORS AND THE LIKE IN WHICH THE RINGS ARE INDIVIDUALLY CLUSTER CAST FROM AN ALLOY-CAST IRON CONTAINING 4.0 TO 5.0% SILICON, 0.6 TO 1.2% BY WEIGHT MANGANESE AND 0.2 TO 0.7% BY WEIGHT PHOSPHORUS. THE CAST IRON IS TREATED IN THE LIQUID STATE WITH BISMUTH TO YIELD A RAW METALLURGICAL STRUCTURE, UPON CASTING, OF CEMENTITE, PEARLITE, LEDEBURITE AND A PHOSPHORIC EUTECTIC.
Inventors
- 👤 Traian Dumitrescu
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 19:08
CPC Classifications
B; B22; B22D; B22D15/00; B22D15/02; Y; Y10; Y10S; Y10S417/00; Y10S417/01
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
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) | 1975-06-27 | 1975-12-27 | 1976-06-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-06-27 | 1979-12-27 | 1980-06-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-06-27 | 1983-12-27 | 1984-06-27 | $7700.00 | Window Closed / Lapsed |