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Patent US3266956A successfully refreshed from Google Patents.
US3266956A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Thermal hardening of rails
Assignee: Union Carbide Corp
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Filing: 1963-11-29
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Granted: 1966-08-16
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Expires: 1983-11-29
Abstract
No abstract record available.
Inventors
- 👤 Robert H Bennewitz
- 👤 Harland R Hedlund
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 14:11
CPC Classifications
C; C21; C21D; C21D9/00; C21D9/04; C21D9/06
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
140 words
METHOD OF THERMALLY HARDENING A ZONE OF STEEL IN THE HEAD OF A RAIL, WHICH COMPRISES JOINING A PLURALITY OF RAIL LENGTHS IN TANDEM, CAUSING RELATIVE MOVEMENT LONGITUDINALLY THEREOF WITH RESPECT TO A SOURCE OF HEAT, SIMULTANEOUSLY APPLYING HEAT FROM SAID SOURCE TO A LOCALIZED ZONE ADJACENT THE TOP SURFACE OF SAID RELATIVELY MOVING RAIL TO HEAT SAID LAYER PROGRESSIVELY TO A HARDENING TEMPERATURE, SIMULTANEOUSLY APPLYING QUANCHING MEDIUM TO SAID HEATED ZONE IN TANDEM TO SAID HEAT APPLICATION TO PROGRESSIVELY HARDEN THE METAL, AND SIMULTANEOUSLY EXERTING AN UPWARD FORCE NORMAL TO THE RAIL BELOW SAID SOURCE OF HEAT TO LIFT THE LENGTH OF RAIL BEING HEATED AND AT LEAST A PORTION OF A LENGTH TANDEM THERETO SO AS TO FORM A PROGRESSIVE LOCALIZED CAMBER IN THE RAIL AND STRETCH THE METAL IN SAID HEATED ZONE SUFFICIENT TO SUBSTANTIALLY EQUALIZE SHRINKAGE.
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) | 1969-08-15 | 1970-02-14 | 1970-08-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-08-15 | 1974-02-14 | 1974-08-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-08-15 | 1978-02-14 | 1978-08-16 | $7700.00 | Window Closed / Lapsed |