US3668916A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Drawing of metal tubing
Assignee: WEAN IND Inc
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Filing: 1970-01-19
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Granted: 1972-06-13
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Expires: 1990-01-19
Abstract
Abstract The method of controlling the wall thickness of a drawn metal tube by applying forces on the tube on opposite sides of the die whereby the tube leaves the die at a higher velocity than the velocity of the tube entering the die, and relating the velocities in a ratio to produce the desired wall thickness of the drawn tube.
Inventors
- 👤 Harry C Ledebur
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 23:46
CPC Classifications
B; B21; B21C; B21C1/00; B21C1/16; B21C1/27; B21C1/30; B21C51/00
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
117 words
In the art of drawing a metal tube through a die without the use of a mandrel to reduce the outside diameter of the tube, the improved method of controlling the wall thickness of the drawn tube to a desired dimension, which comprises: controlling tube movement by applying forces to the tube on opposite sides of the die whereby the tube leaves said die at a higher velocity than the velocity of the tube entering said die, and relating the entering and leaving velocities of the tube in a ratio solely predetermined by the outside diameter and wall thickness of the tube before drawing and the desired wall thickness and reduced outside diameter of the drawn tube.
Claim 2
Dependent Claim
117 words
In the art of drawing a metal tube through a die without the use of a mandrel to reduce the outside diameter of the tube, the improved method of controlling the wall thickness of the drawn tube to a desired dimension, which comprises: controlling tube movement by applying forces to the tube on opposite sides of the die whereby the tube leaves said die at a higher velocity than the velocity of the tube entering said die, and relating the entering and leaving velocities of the tube in a ratio solely predetermined by the outside diameter and wall thickness of the tube before drawing and the desired wall thickness and reduced outside diameter of the drawn tube.
Claim 3
Dependent Claim
67 words
The method of claim 1 wherein the ratio of the entering and leaving velocities of the tube are predetermined in accordance with the mathematical equation t2(d2-t2) t1(d1-t1) (V1/V2) where t2 is the desired wall thickness of the drawn tube, d2 is the reduced outside diameter of the drawn tube, and d1 and t1 are, respectively, the outside diameter and wall thickness of the tube before being drawn.
References Cited (Backward Citations)
US2108790A
Cited
US2159561A
Cited
US2717072A
Cited
US3013652A
Cited
US3238752A
Cited
US3572078A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-06-13 | 1975-12-13 | 1976-06-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-06-13 | 1979-12-13 | 1980-06-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-06-13 | 1983-12-13 | 1984-06-13 | $7700.00 | Window Closed / Lapsed |