Patent US4035858A successfully refreshed from Google Patents.
US4035858A
Expired / Lapsed
US
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Process for the preuse work-hardening of bolts
Assignee: Individual
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Filing: 1976-03-08
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Granted: 1977-07-19
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Expires: 1996-03-08
Abstract
Abstract A method for manufacturing bolts of a given grade and size in which, after forming, threading and heat treating, each bolt is work hardened by the application and subsequent removal of a tensile force of magnitude somewhat above the minimum proof load for the given grade and size of bolt, so that all bolts so treated will have the same yield point and the torque rotation curve for each bolt will have a discontinuity in slope at this common yield point.
Inventors
- 👤 Norman C. Dahl
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 04:58
CPC Classifications
B; B21; B21K; B21K1/00; B21K1/44; Y; Y10; Y10S; Y10S411/00; Y10S411/916; Y10T; Y10T29/00; Y10T29/49; Y10T29/49826; Y10T29/49863; Y10T29/49874
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
103 words
In a method for manufacturing bolts of a given grade and size having a minimum proof load which method comprises the steps of forming blanks into bolts having heads and shanks, threading said shanks, and heat treating the formed bolts, wherein the improvement comprises work hardening each bolt by applying and subsequently removing a tensile force of uniform magnitude somewhat above the minimum proof load for the given grade and size of bolt, so that all bolts so treated will have the same yield point and the torque-rotation curve for each bolt will have a discontinuity in slope at this common yield point.
Claim 2
Dependent Claim
103 words
In a method for manufacturing bolts of a given grade and size having a minimum proof load which method comprises the steps of forming blanks into bolts having heads and shanks, threading said shanks, and heat treating the formed bolts, wherein the improvement comprises work hardening each bolt by applying and subsequently removing a tensile force of uniform magnitude somewhat above the minimum proof load for the given grade and size of bolt, so that all bolts so treated will have the same yield point and the torque-rotation curve for each bolt will have a discontinuity in slope at this common yield point.
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) | 1980-07-18 | 1981-01-17 | 1981-07-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-07-18 | 1985-01-17 | 1985-07-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-07-18 | 1989-01-17 | 1989-07-19 | $7700.00 | Window Closed / Lapsed |