Patent US3877272A successfully refreshed from Google Patents.
US3877272A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for hydrostatic extrusion of tubes and billets
Assignee: ABB Norden Holding AB
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Filing: 1974-02-08
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Granted: 1975-04-15
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Expires: 1994-02-08
Abstract
Abstract In the hydrostatic extrusion of tubes, a billet is provided which has a bore at its rear end in which is inserted a sleeve of harder material than the material of the billet, for example steel in a billet of aluminium or copper, and the billet is then extruded through a die opening around a mandrel. The sleeve is of greater thickness than the space between the mandrel and the wall of the die opening so that it stops or retards extrusion when the sleeve reaches the point of the die opening.
Inventors
- 👤 Gunnar Brunosson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 20:19
CPC Classifications
B; B21; B21C; B21C23/00; B21C23/007; Y; Y10; Y10T; Y10T428/00; Y10T428/12; Y10T428/12292; Y10T428/12493; Y10T428/12736; Y10T428/1275; Y10T428/12757; Y10T428/12771; Y10T428/12861; Y10T428/12903; Y10T428/12917; Y10T428/12924; Y10T428/12951; Y10T428/12972
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
120 words
A method for the hydrostatic extrusion of tubes which comprises inserting into a pressure chamber having a die opening and a mandrel passing through the die opening and of less diameter than the die opening a billet having a central hole therethrough and having a bore at the rear end, and a sleeve in said bore formed of a material which is harder than the material of the billet and has a larger inner diameter than the diameter of the mandrel, the sleeve having a greater thickness of material than the space between the die opening and the mandrel and being substantially shorter than the billet, thereby to prevent the billet from being completely pressed out of the die opening.
Claim 2
Independent Claim
120 words
A method for the hydrostatic extrusion of tubes which comprises inserting into a pressure chamber having a die opening and a mandrel passing through the die opening and of less diameter than the die opening a billet having a central hole therethrough and having a bore at the rear end, and a sleeve in said bore formed of a material which is harder than the material of the billet and has a larger inner diameter than the diameter of the mandrel, the sleeve having a greater thickness of material than the space between the die opening and the mandrel and being substantially shorter than the billet, thereby to prevent the billet from being completely pressed out of the die opening.
Claim 3
Dependent Claim
27 words
A method as claimed in claim 1, in which the sleeve has substantially the same inner diameter as the inner diameter of the hole in the billet.
Claim 4
Dependent Claim
16 words
A method as claimed in claim 2, in which the bore is longer than the sleeve.
Claim 5
Dependent Claim
26 words
A method as claimed in claim 1, in which the sleeve has a greater thickness of material at its rear end than at its front end.
Claim 6
Dependent Claim
44 words
A billet for use in the hydrostatic extrusion of tubes, having a central bore therethrough and having a sleeve inserted in its rear end concentric with the bore and of harder material than the material of the billet and substantially shorter than the billet.
Claim 7
Dependent Claim
44 words
A billet for use in the hydrostatic extrusion of tubes, having a central bore therethrough and having a sleeve inserted in its rear end concentric with the bore and of harder material than the material of the billet and substantially shorter than the billet.
Claim 8
Dependent Claim
34 words
A billet as claimed in claim 5, in which billet has a bore at its rear end with a larger diameter than the hole in the billet, the sleeve being inserted in such bore.
Claim 9
Dependent Claim
16 words
A billet as claimed in claim 6, in which the bore is longer than the sleeve.
Claim 10
Dependent Claim
24 words
A billet as claimed in claim 5 in which the sleeve has a larger diameter at its rear end than at its front end.
Claim 11
Dependent Claim
20 words
A billet as claimed in claim 5, in which the billet is of copper and the sleeve is of steel.
Claim 12
Dependent Claim
20 words
A billet as claimed in claim 5, in which the billet is of aluminium and the sleeve is of steel.
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) | 1978-04-14 | 1978-10-14 | 1979-04-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-04-14 | 1982-10-14 | 1983-04-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-04-14 | 1986-10-14 | 1987-04-15 | $7700.00 | Window Closed / Lapsed |