US4223548A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process and device for extruding hollow sections
Assignee: Rio Tinto Switzerland AG
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Filing: 1979-03-14
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Granted: 1980-09-23
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Expires: 1999-03-14
Abstract
Abstract A process for the extrusion of tubes or similar hollow sections from a billet is disclosed within the billet is forced against a hollow extrusion die surrounding a mandrel and a mandrel support. A core passing through the extrusion billet moves in the direction of extrusion with the billet and is led through the mandrel into the space inside the resultant hollow section. The process of the present invention relieves the die of the high stresses which can otherwise lead to early failure of the die.
Inventors
- 👤 Alfred Wagner
- 👤 Adolf Ames
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 21:14
CPC Classifications
B; B21; B21C; B21C23/00; B21C23/02; B21C23/04; B21C23/08; B21C23/085; B21C25/00
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
104 words
A method for extruding hollow sections or the like comprising: loading a hollow billet into a container; locating an extrusion tool comprising a die, a hollow mandrel and a mandrel support at the end of said container such that said die surrounds said hollow mandrel; moving a hollow stem in a first direction into said container from the opposite end thereof so as to urge said billet through said die so as to form said hollow section; and passing a core through said stem, said hollow billet and said hollow mandrel thereby reducing the high stresses on said hollow mandrel and said mandrel support.
Claim 2
Independent Claim
104 words
A method for extruding hollow sections or the like comprising: loading a hollow billet into a container; locating an extrusion tool comprising a die, a hollow mandrel and a mandrel support at the end of said container such that said die surrounds said hollow mandrel; moving a hollow stem in a first direction into said container from the opposite end thereof so as to urge said billet through said die so as to form said hollow section; and passing a core through said stem, said hollow billet and said hollow mandrel thereby reducing the high stresses on said hollow mandrel and said mandrel support.
Claim 3
Dependent Claim
20 words
A method according to claim 1 wherein the core moves at a speed equal to the speed of said stem.
Claim 4
Dependent Claim
22 words
A method according to claim 1 wherein the core moves at a speed equal to the flow rate of the extruded billet.
Claim 5
Dependent Claim
20 words
A method according to claim 1 wherein the core moves at a speed different from the speed of said ram.
Claim 6
Dependent Claim
17 words
A method according to claim 4 further including means independent of said stem for moving said core.
Claim 7
Dependent Claim
24 words
A method according to claim 5 wherein said means for moving said core is controlled and altered automatically during the extrusion of said billet.
Claim 8
Dependent Claim
28 words
A method according to claim 1 wherein said core is passed through said billet in frictional contact therewith so as to aid in the extrusion of said billet.
Claim 9
Dependent Claim
28 words
A method according to claim 1, further including heating means provided in said core so as to alter the flow characteristics of said billet during the extrusion thereof.
Claim 10
Dependent Claim
28 words
A method according to claim 1 further including cooling means provided in said core so as to alter the flow characteristics of said billet during the extrusion thereof.
Claim 11
Independent Claim
92 words
An apparatus for extruding hollow sections or the like comprising: an extrusion tool comprising a hollow mandrel, a die which surrounds said hollow mandrel and a mandrel support; stem means positioned with respect to said extrusion tool and movable in a first direction for forcing a hollow billet therethrough; and core means movable in said first direction through said stem, said hollow billet and said hollow mandrel whereby said core aids in the extrusion of said billet while at the same time reducing stresses on said hollow mandrel and said mandrel support.
Claim 12
Independent Claim
92 words
An apparatus for extruding hollow sections or the like comprising: an extrusion tool comprising a hollow mandrel, a die which surrounds said hollow mandrel and a mandrel support; stem means positioned with respect to said extrusion tool and movable in a first direction for forcing a hollow billet therethrough; and core means movable in said first direction through said stem, said hollow billet and said hollow mandrel whereby said core aids in the extrusion of said billet while at the same time reducing stresses on said hollow mandrel and said mandrel support.
Claim 13
Dependent Claim
44 words
An apparatus according to claim 10 wherein the diameter of said core is substantially equal to the inner diameter of said hollow billet wherein said stem comprises a ram face and a hollow extrusion stem and said core is positioned within said hollow stem.
Claim 14
Dependent Claim
14 words
An apparatus according to claim 11 wherein said core is fixed to said stem.
Claim 15
Dependent Claim
20 words
An apparatus according to claim 11 wherein said core further includes means for moving said core independently of said stem.
Claim 16
Dependent Claim
25 words
An apparatus according to claim 13 wherein said means comprises an automatic control unit for changing the speed and/or direction of movement from said core.
Claim 17
Dependent Claim
18 words
An apparatus according to claim 10 wherein said extrusion tool comprises shell-like bearing means for supporting said core.
Claim 18
Dependent Claim
22 words
An apparatus according to claim 15 wherein said shell-like bearing means can be moved so as to allow adjustment of said core.
Claim 19
Dependent Claim
14 words
An apparatus according to claim 10 wherein said mandrel is separable from said die.
Claim 20
Dependent Claim
25 words
An apparatus according to claim 10 wherein a portion of said core is hollow and comprises means for altering the flow characteristics of said billet.
Claim 21
Dependent Claim
20 words
An apparatus according to claim 18 wherein said means for altering the flow characteristics of said billet comprises heating means.
Claim 22
Dependent Claim
20 words
An apparatus according to claim 18 wherein said means for altering the flow characteristics of said billet comprises cooling means.
References Cited (Backward Citations)
GB395906A
Cited
US2337804A
Cited
US2491897A
Cited
US3213662A
Cited
JPS4819782B1
Cited
US3455137A
Cited
US3675457A
Cited
US3798954A
Cited
SU461751A1
Cited
SU489547A1
Cited
SU504574A1
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-09-23 | 1984-03-24 | 1984-09-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-09-23 | 1988-03-24 | 1988-09-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-09-23 | 1992-03-24 | 1992-09-23 | $7700.00 | Window Closed / Lapsed |