US3645121A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for rolling tubular material stock in a stretch reducing mill
Assignee: Vodafone GmbH
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Filing: 1969-07-01
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Granted: 1972-02-29
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Expires: 1989-07-01
Abstract
Abstract A method for rolling down tubular material in a rolling mill wherein in the vicinity of the starting sections and/or end sections of the tubular material normally having thickened portions a stepwise variation of the rotational speeds is provided at the roll stands deforming these sections, said stepwise variation of said rotational speeds required for rolling the central section of the tubular material.
Inventors
- 👤 Gerd Pfeiffer
- 👤 Horst Biller
- 👤 Claus Schrey
- 👤 Alfred Schmitz
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 10:20
CPC Classifications
B; B21; B21B; B21B17/00; B21B17/14
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
136 words
A method of rolling down tubular material in a rolling mill in which the rolls of consecutive stands normally operate gradually increasing rotational speed, which comprises: a stepwise reduction of the rotational roll speedS at a plurality of roll stands prior to entry of the front section of the tubular material, the percentage of the rotational speed reduction being at a maximum at the first stand location and decreasing at the subsequent stands; and subsequently, upon entry of the front section of the tubular material into the rolling mill, an increase in speed of the individual stand locations, dependent on the passing of such front section through a plurality of stand locations, to the rotational speed sequence for a filled rolling mill, so that the normally thickened front section of the tubular material is substantially shortened.
Claim 2
Independent Claim
136 words
A method of rolling down tubular material in a rolling mill in which the rolls of consecutive stands normally operate gradually increasing rotational speed, which comprises: a stepwise reduction of the rotational roll speedS at a plurality of roll stands prior to entry of the front section of the tubular material, the percentage of the rotational speed reduction being at a maximum at the first stand location and decreasing at the subsequent stands; and subsequently, upon entry of the front section of the tubular material into the rolling mill, an increase in speed of the individual stand locations, dependent on the passing of such front section through a plurality of stand locations, to the rotational speed sequence for a filled rolling mill, so that the normally thickened front section of the tubular material is substantially shortened.
Claim 3
Dependent Claim
41 words
A method as defined in claim 1, wherein the percentage increase of the rotational speeds to the rotational speeds for the filled rolling mill is effected uniformly at all stand locations through which the front section of the tubular material passes.
Claim 4
Dependent Claim
50 words
A method as defined in claim 2, wherein the rotational speeds of the stand locations through which the front section of the tubular material passes are respectively increased such that they attain the same percentage speed reduction as the last stand location rolling the front section of the tubular material.
Claim 5
Independent Claim
180 words
A method of rolling down tubular material in a rolling mill in which the rolls of consecutive stands normally operate with gradually increasing rotational speed, wherein with the rolling mill filled the roll speeds of all stands, p in number, participating in the deformation of the tubular material are reduced relative to the speed sequence employed for rolling the central section of the tubular material, the percentage rotational speed reduction at all stands being equal, and wherein subsequently upon entry of the rear section of the tubular material is consecutive stands 1 through n of the rolling mill the reduced speeds of the stands 2 through p are increased dependent on the passing of the rear section of the tubular material through the stands 1 through n such that in the vicinity of the rear section of the tubular material the percentage rotational speed reduction decreases with an increasing stand location number up to the stand location n, and wherein the central section of the tubular material is rolled in stands the percentage rotational speed reduction of which is equal.
Claim 6
Independent Claim
180 words
A method of rolling down tubular material in a rolling mill in which the rolls of consecutive stands normally operate with gradually increasing rotational speed, wherein with the rolling mill filled the roll speeds of all stands, p in number, participating in the deformation of the tubular material are reduced relative to the speed sequence employed for rolling the central section of the tubular material, the percentage rotational speed reduction at all stands being equal, and wherein subsequently upon entry of the rear section of the tubular material is consecutive stands 1 through n of the rolling mill the reduced speeds of the stands 2 through p are increased dependent on the passing of the rear section of the tubular material through the stands 1 through n such that in the vicinity of the rear section of the tubular material the percentage rotational speed reduction decreases with an increasing stand location number up to the stand location n, and wherein the central section of the tubular material is rolled in stands the percentage rotational speed reduction of which is equal.
Claim 7
Dependent Claim
30 words
A method as defined in claim 4, wherein the percentage increase of the rotational speeds of the stands which roll the central section of the tubular material is effected uniformly.
Claim 8
Independent Claim
107 words
A method of rolling down tubular material in a rolling mill in which the rolls of consecutive stands normally operate with gradually increasing rotational speed, wherein upon entry of the rear section of the tubular material in consecutive stands 1 through q the associated roll rotational speeds thereof are reduced dependent on the passing of the rear section of the tubular material through these stands such that in the vicinity of the rear section of the tubular material the percentage rotational speed reduction decreases with an increasing stand location number and wherein the central section of the tubular material is rolled in stands with unaltered rotational speeds.
Claim 9
Independent Claim
107 words
A method of rolling down tubular material in a rolling mill in which the rolls of consecutive stands normally operate with gradually increasing rotational speed, wherein upon entry of the rear section of the tubular material in consecutive stands 1 through q the associated roll rotational speeds thereof are reduced dependent on the passing of the rear section of the tubular material through these stands such that in the vicinity of the rear section of the tubular material the percentage rotational speed reduction decreases with an increasing stand location number and wherein the central section of the tubular material is rolled in stands with unaltered rotational speeds.
Claim 10
Dependent Claim
29 words
A method as defined in claim 6, wherein the percentage rotational speed reduction of the stand group respectively rolling the rear section of the tubular material is effected uniformly.
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) | 1975-02-28 | 1975-08-30 | 1976-02-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-02-28 | 1979-08-30 | 1980-02-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-02-28 | 1983-08-30 | 1984-02-29 | $7700.00 | Window Closed / Lapsed |