U.S. patent application number 14/384808 was filed with the patent office on 2015-01-29 for apparatus for straightening metal strip.
This patent application is currently assigned to SMS Siemag Aktiengesellschaft. The applicant listed for this patent is SMS Siemag Aktiengesellschaft. Invention is credited to Jens Artel, Frank-Gunter Benner, Roman Dehmel, Rolf Franz, Peter Jollet, Matthias Kipping.
Application Number | 20150027185 14/384808 |
Document ID | / |
Family ID | 47988909 |
Filed Date | 2015-01-29 |
United States Patent
Application |
20150027185 |
Kind Code |
A1 |
Benner; Frank-Gunter ; et
al. |
January 29, 2015 |
APPARATUS FOR STRAIGHTENING METAL STRIP
Abstract
An apparatus for straightening metal strips, including a first,
upper group and a second, lower group of straightening rollers
arranged in each case immediately in succession in a strip running
direction, and a group of individually controllable actuators
arranged alongside one another in a transverse direction. An axial
bending profile of at least a first of the straightening rollers is
settable by the group of actuators. At least one second group of
individually controllable actuators arranged alongside one another
in the transverse direction is provided. An axial bending profile
of the least a second of the straightening rollers, which is in
particular different from the bending profile of the first bending
roller, is settable by the second group of actuators.
Inventors: |
Benner; Frank-Gunter;
(Hilchenbach, DE) ; Dehmel; Roman; (Grevenbroich,
DE) ; Franz; Rolf; (Kreuztal, DE) ; Kipping;
Matthias; (Herdorf, DE) ; Jollet; Peter;
(Dusseldorf, DE) ; Artel; Jens; (Kirchhundem,
DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
SMS Siemag Aktiengesellschaft |
Dusseldorf |
|
DE |
|
|
Assignee: |
SMS Siemag
Aktiengesellschaft
Dusseldorf
DE
|
Family ID: |
47988909 |
Appl. No.: |
14/384808 |
Filed: |
March 12, 2013 |
PCT Filed: |
March 12, 2013 |
PCT NO: |
PCT/EP2013/054989 |
371 Date: |
September 12, 2014 |
Current U.S.
Class: |
72/8.4 ;
72/162 |
Current CPC
Class: |
B21B 38/02 20130101;
B21D 1/02 20130101; B21B 37/40 20130101 |
Class at
Publication: |
72/8.4 ;
72/162 |
International
Class: |
B21D 1/02 20060101
B21D001/02; B21B 37/40 20060101 B21B037/40; B21B 38/02 20060101
B21B038/02 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 15, 2012 |
DE |
10 2012 204 074.9 |
Claims
1-13. (canceled)
14. An apparatus for straightening metal strips, comprising: a
first, upper group and a second, lower group of straightening rolls
arranged successively in a strip travel direction; and a group of
individually controllable actuators, arranged next to each other in
a transverse direction, and at least one second group of
individually controllable actuators arranged next to each other in
the transverse direction, wherein the group of actuators are
operative to adjust an axial bending profile of at least one first
straightening roll, and the second group of actuators are operative
to adjust an axial bending profile of at least one second
straightening roll in a manner different from the bending profile
of the first straightening roll.
15. The apparatus according to claim 14, wherein at least three
groups of actuators are provided arranged successively in the strip
travel direction, each group consisting of at least three
actuators, which groups form overall a field of individually
controllable actuators by which bending profiles of several
straightening rolls arranged successively in the strip travel
direction are independently adjustable.
16. The apparatus according to claim. 14, wherein the actuators
comprise a hydraulic cylinder.
17. The apparatus according to claim 14, wherein at least one of
the groups of actuators is supported on a dimensionally stable
crossbeam.
18. The apparatus according to claim 17, further comprising a
crossbeam actuator operatively arranged to adjust tilting of the
crossbeam around the strip travel direction.
19. The apparatus according to claim 14, further comprising side
actuators arranged to subject bearing areas at ends of at least one
of the straightening rolls to adjustable loads.
20. The apparatus according to claim 19, wherein the bearing areas
at the ends of the at least one of the straightening rolls are
subjected to adjustable loads in a direction opposite to the
actuators.
21. The apparatus according to claim 14, further comprising a
mounting arrangement for a plurality of support rolls, wherein the
actuators act on the mounting arrangement and the support rolls
transmit force of the actuators to the straightening roll.
22. The apparatus according to claim 21, wherein the mounting
arrangement comprises a chain of bearing sections, connected to
each other in the axial direction, for the support rolls.
23. The apparatus according to claim 14, further comprising a
respective measuring unit arranged both in front of and behind the
groups of straightening rolls for measuring flatness defects and/or
stresses in the metal strip, wherein the measuring units are used
to adjust the straightening rolls during a straightening
process.
24. The apparatus according to claim 21, wherein the measuring
units are configured to undertake an optical measurement of the
form of the metal strip, wherein the metal strip is guided
substantially without tension at least in an area of the measuring
units.
25. A method for straightening a metal strip using an apparatus
according to claim 14, comprising the steps: a. measuring the form
and/or stresses of a metal strip with a measuring unit before a
first pass through a straightening section; b. adjusting
straightening rolls of a straightening section as a function of the
measurement of the metal strip; c. straightening the metal strip by
passage through the straightening section; and d. measuring the
form and/or stresses of the metal strip with a second measuring
unit t an exit from the straightening section.
26. The method according to claim 25, including adjusting the
straightening rolls with an electronic control unit.
27. The method according to claim 25, including repeating steps b
and c as a function of a measurement result in step d.
28. The method according to claim 25, wherein the metal strip
passes through the straightening section first in one direction and
then, in a following pass, in an opposite direction.
Description
[0001] The invention pertains to an apparatus for straightening
metal strip according to the introductory clauses of claim 1 and
claim 9 and to a method for straightening metal strip with the
features of claim 12.
[0002] U.S. Pat. No. 4,881,392 describes a system for straightening
metal strip in which a straightening section is installed
downstream from a rolling mill, and in which a measuring device for
measuring the flatness of the metal strip is installed downstream,
relative to the travel direction, from the straightening
section.
[0003] The goal of the invention is to provide an apparatus and a
method for straightening metal strips in which the straightening
process is effectively optimized.
[0004] For a previously mentioned apparatus according to the
introductory clause of claim 1, this goal is achieved according to
the invention by the characterizing features of claim 1.
[0005] By means of the at least second group of individually
controllable actuators arranged next to each other in the
transverse direction, by means of which the axial bending profile
of at least one second straightening roll can be adjusted, the
action of the straightening rolls on the sheet can be adjusted in
an especially well-differentiated manner.
[0006] In a preferred embodiment of the invention, it is provided
that at least three groups of actuators arranged successively in
the strip travel direction are provided, each group consisting of
at least three actuators, which groups form a field of individually
controllable actuators, by means which the bending profile of each
of several straightening rolls arranged successively in the strip
travel direction can be independently adjusted. Such a field of
actuators generally makes it possible for the straightening process
to achieve a very precise correction of strip defects. If
necessary, furthermore, a local correction can be carried out
dynamically, especially in relatively short sections of the strip.
Such relatively local strip defects can, for example, be detected
by a measuring device installed at the entrance to the
apparatus.
[0007] In general, it is preferably provided that the actuators
comprise a hydraulic cylinder.
[0008] Hydraulic cylinders can be adapted quickly and over a wide
range to the requirements on the straightening forces. In an
alternative or supplemental elaboration, however, it is also
possible to be use thread-controlled, wedge-controlled, or other
types of actuators.
[0009] In a preferred embodiment, at least one, preferably several,
groups of actuators are supported on a rigid crossbeam. "Rigid" is
to be understood within the scope of the invention as meaning that
the area moment of inertia of the crossbeam is at least a multiple
of the area moment of inertia of the straightening rolls. In a
further elaboration, the tilt of the crossbeam around the strip
travel direction can be adjusted by means of at least one crossbeam
actuator. As a result, the apparatus is given even more
possibilities for adjustment. The crossbeam actuators can also be,
and preferably are, hydraulic actuators; alternatively or in
addition, they can also be wedge-controlled or thread-controlled
devices.
[0010] In a generally preferred elaboration, it is provided that
the bearing areas at the ends of at least one straightening roll
can be subjected to variable load by side actuators, e.g.,
subjected in particular to load acting in the direction opposite to
the actuators. As a result, it is possible, among other things, to
adjust the gaps and applied forces easily. The side actuators can
preferably be configured as hydraulic cylinders.
[0011] In a simple and generally preferred engineering realization,
the actuators can act on a mounting arrangement for a plurality of
support rolls, wherein the support rolls transfer the force of the
actuators to one of the straightening rolls. In a preferred
elaboration, the mounting arrangement comprises a chain of bearing
sections for the support rolls, connected to each other in the
axial direction. As a result, forces occurring in the axial
direction can be absorbed in optimal fashion, so that the action of
the individual actuators is locally well defined, and no canting or
the like can occur in the area of the actuators or support
rolls.
[0012] The goal of the invention is also achieved for an apparatus
according to the introductory clause of claim 9 by the
characterizing features of claim 9. As a result of the arrangement
of a measuring unit before the groups straightening rolls, an
especially good measurement can be made, on the basis of which the
number of passes through the straightening section can be
minimized. In particular, the upstream measurement unit makes it
possible to decide whether or not any straightening at all is
necessary. In the ideal case, the strip can then completely bypass
the straightening section or pass through it without any pressure
being exerted on it by the straightening rolls.
[0013] Through the provision of two measuring units, one in front
of, the other behind, the straightening rolls, it can be decided in
the same pass whether or not a second pass through the
straightening section is necessary. From a comparison of the
measurements made by the two measuring units, i.e., by the one
before the straightening section and the by one after it, it is
also possible to derive values for optimizing or changing the
settings of the actuators of the straightening section in order to
make it possible to optimize the subsequent pass. This can be the
second pass or in general the n-th pass.
[0014] In a preferred elaboration, the measuring units comprise the
optical, especially the laser-optical measurement of the form of
the metal strip, wherein the metal strip, at least in the area of
the measuring units, is guided through in a state at least largely
free of tension. Largely tension-free guidance is present when the
tensile forces caused by the guidance of the strip are kept as
small as possible, i.e., so small that they have only a negligible
effect on the three-dimensional deformation of the
[0015] In alternative or supplemental elaborations, it is also
possible, besides the optical detection of a 3-dimensional
deformation, to make provisions for scanning the strip by means of
mechanical scanning rollers at a defined tensile stress in order to
measure the variable stresses across the width and to use the
results as a criterion for adjusting the actuators of the
straightening section.
[0016] In general it is advantageous for the apparatus according to
claim 9 or claim 10 also to comprise one or more additional
features according to one of claims 1-8. It is obvious that, in
individual cases, the specific embodiments of such an apparatus can
be combined in any way desired with the concept of an apparatus in
which a measuring unit is installed both before and after the
straightening rolls.
[0017] The goal of the invention is also achieved by a method for
straightening metal strip with the features of claim 12. It is
especially preferred but not mandatory that an apparatus according
to the invention be used for a method according to the
invention.
[0018] By using a first, upstream measuring unit to measure the
form and/or stresses before a first pass through the straightening
section and to use a second measuring unit installed after the
straightening section to do the same, the straightening process can
be optimized in an especially effective manner, and the number of
passes through the straightening section which might be necessary
can be minimized. It is obvious that, in addition, data from
preceding passes of the same strip and/or from stored models,
especially models pertaining to the material to be straightened,
data on the strip weights, etc, can also be used.
[0019] In an advantageous elaboration, it is provided that steps b
and c are repeated as a function of the measurement result in step
d.
[0020] In particular, a second or n-th pass of the strip can occur
in the direction opposite that of the preceding pass.
[0021] Additional advantages and features of the invention can be
derived from the following exemplary embodiments described below
and from the dependent claims.
[0022] In the following, a preferred exemplary embodiment of the
invention is described and explained in greater detail on the basis
of the attached drawings:
[0023] FIG. 1 shows a schematic diagram of an apparatus according
to the invention from the front;
[0024] FIG. 2 shows a schematic diagram of the apparatus of FIG. 1
from above;
[0025] FIG. 3 shows the apparatus of FIG. 1 in a second state of
actuation;
[0026] FIG. 4 shows the apparatus of FIG. 1 in a third state of
actuation;
[0027] FIGS. 5a-5f show several modifications of bearing sections
of an apparatus of FIG. 1; and
[0028] FIG. 6 shows an overall schematic diagram of an apparatus
according to the invention with two measuring units.
[0029] In FIG. 1, only the upper half of the apparatus for
straightening metal strip is illustrated, this upper half
comprising several straightening rolls 1, arranged successively in
the travel direction of the strip (perpendicular to the plane of
the drawing in FIG. 1).
[0030] Each straightening roll I is subjected to force by a group
of actuators 2, which are arranged next to each other in the
transverse, i.e., axial, direction, along the length of the
straightening roll 1. Each of the actuators comprises a
force-exerting unit in the form of a separately and automatically
controllable hydraulic cylinder 2a, which acts on a bearing section
3 of a chain 4 of bearing sections. In an appropriate configuration
(not shown), one end of the piston of the actuator 2a can press
tiltably on the bearing section, for example. It is obvious that
the bending profile of the straightening roll 1 produced by the
actuators is exaggerated in FIGS. 1, 3, and 4 for clarity of
illustration.
[0031] A pair of support rolls 5 is rotatably supported on each
bearing section 3; these support rolls press on the straightening
rolls 1 and thus adjust their bending profile as they rotate.
[0032] FIGS. 5a-5f show various alternative configurations of the
chain of bearing sections. In the case of the configurations
according FIGS. 5a-5c, the bearing sections 3 abut one another,
wherein the cooperating end surfaces can be shaped as requirements
demand. FIG. 5a shows a simple formation with flat end surfaces.
FIG. 5b shows a two convex formations, which have the result of
reducing the area subject to friction. FIG. 5c shows a concave end
surface, into which an adjacent, convex end surface fits,so that
the two bearing sections precisely assume their proper positions
relative to each other.
[0033] In the examples according to FIGS. 5d-5f, the adjacent
bearing sections are connected to each other in each case, wherein
the connecting point provides an increased degree of mobility
versus a homogeneous bar. In FIG. 5d, this increased mobility is
achieved by the local removal, of material from a solid bar. FIG.
5e shows a connection by means of an elastic connector, which can
consist of metal or of some other material, installed between the
bearing sections. FIG. 5f shows an arrangement in which the
adjacent bearing sections are connected to each other by a joint,
e.g., a rotary joint.
[0034] The actuators 2 with their hydraulic cylinders are supported
on the side opposite the straightening roll by a nonflexing or
dimensionally stable crossbeam 6. The crossbeam is tiltably
adjustable by way of crossbeam actuators 7, two such actuators
being present here, in order to provide a further adjustment
possibility for straightening and/or to allow the crossbeam to be
moved aside for maintenance purposes. The crossbeam actuators 7 are
also configured as hydraulic cylinders.
[0035] The straightening rolls 7 are mounted at the ends in rotary
bearings 8, each of which for its own part is supported on the
crossbeam 6 in force-adjustable fashion by way of side actuators 9.
In particular, the side actuators 9 can be subjected to force in
the direction opposite to the actuators 2 in order to adjust the
bending profile of the straightening rolls 7.
[0036] It can be seen in particular from the schematic diagram of
FIG. 2 that, in the present case, the bending profile of each of
the straightening rolls 1, five in this example, arranged one after
the other, can be adjusted substantially individually. For this
purpose, a group of actuators 2, arranged axially next to each
other, is provided for each straightening roll 1. In the present
example, each of the five straightening rolls 1 is adjusted by one
group of five actuators in each case, arranged next to each other
in the transverse direction, so that, overall, a field of 5.times.5
separately adjustable actuators 2 is obtained.
[0037] The five straightening rolls 1 are mounted at the ends on
beams 10, in which the rotary bearings 8 of the straightening rolls
1 are arranged. Each of the two beams 10 is held by one of the side
actuators 9. The beams are advisably guided in such a way that that
no tipping in the strip travel direction can occur. Alternatively
or in addition, several side actuators 9 can also act on the same
beam 10. As another alternative, each individual straightening roll
1 can be mounted at the ends in side actuators 7; or several, e.g.,
two, straightening rolls can be combined into a unit with respect
to their rotational support by their own assigned beams.
[0038] All of the hydraulic cylinders described above have
preferably a circular cross section. It is a principle of the
present invention that as many standard actuators of the same
configuration as possible be used and that no custom configurations
such as cylinders with an elongated cross section be needed.
[0039] The upper half of the apparatus described above can be
repeated in an essentially symmetric manner as the lower half with
a group of lower straightening rolls 1' (see the schematic diagram
of FIG. 6). As a result, it is possible, as shown in FIG. 3, to
bend the straightening roll in a manner which is the inverse of
that shown in FIG. 1, wherein the application of the thrusting
forces is accomplished by the actuators (not shown) of the lower
half.
[0040] In the case of the positioning according to FIG. 4, the
straightening roll is being tilted around the strip travel
direction. A tilting of this type can, as shown, be accomplished by
the actuators 2, 7 or possibly by the tilting of the crossbeam
6.
[0041] The schematic side view according to FIG. 6 shows an
apparatus as described above, to which a first measuring system 11
is assigned in the upstream direction relative to strip travel and
a second measuring system 12 in the downstream direction.
[0042] The measuring systems 11, 12 are identical in design and
measure irregularities of the largely tension-free metal strip 13
by means of optical systems, especially laser-optic systems.
[0043] FIG. 6 also explains a method in which, according to the
invention, the topography or flatness and/or the internal stresses
of the metal strip 13 are first determined before the straightening
process. For this purpose, the data obtained by the first measuring
unit 11 are transmitted over a connection 11a to an electronic
control unit or to a model 14 installed in such a unit. For the
measurement, the metal strip 13 can rest on rollers 15, for
example, as it is being scanned. It is also conceivable that the
flatness and/internal stresses of the metal strip could be detected
during a pass. For this purpose, a reversing mode would also be
possible.
[0044] All of the straightening rolls 1, but at least the upper
straightening rolls 1, are preferably equipped with sensors 16 and
actuators 17 and are connected by the lines 18 to the model 14. The
sensors can measure forces, for example, or moments, positions,
inclinations, deformations, etc. The actuators, such as the
actuators 2 described above, are able to transmit forces and
moments and to change positions by traveling or tilting and thus
cause deformations. As a result, the straightening rolls 1 can be
brought into as many different positions and deforming states as
desired and thus assume any desired positioning relative to each
other.
[0045] As a result of the additional measuring unit 12 downstream
from the straightening rolls, the metal strip 13 could be measured
again, at least as an option. The resulting data are made available
to the model 14 over a connecting line 12a.
[0046] The model 14 is described in one or more computers and
consists of additionally implemented submodels. These are materials
models for the materials to be straightened, models for describing
the straightening process, mechanical models for describing machine
components and their interaction during straightening, models for
processing the sensor signals, models for processing and working up
the geometry (flatness/planarity defects) and internal stresses of
the material 13 to be straightened, models for correcting flatness
defects, models for controlling the actuators of the straightening
machine, etc.
[0047] All of the data and signals are tied into corresponding
models, feedback control circuits, and algorithms. Integration and
processing take place in a higher-level technological model.
[0048] This model could, for example, decide, either independently
or with operator support, whether or not the metal strip 13 should
be straightened again or whether it can be released for further
processing. The local penetration depth E1 into the plane P_1 up to
the penetration depth En in plane P_n can be set by the model 14 as
necessary to meet the requirements on the end product. The "local
penetration depth" is to be understood not only as the parallel
straightening gap RS but also as a non-constant straightening gap
RS, which can arise through the tilting and bending of at least one
of the straightening rolls 1. The straightening machine can be
operated with the help of the model 14 in such a way that it can
change the penetration depths and the straightening gaps either
statically or dynamically (during the straightening process). It is
also conceivable that the support width a could be adjusted by
moving the straightening rolls 1, such movement being controlled in
open-loop or closed-loop fashion by the model 14.
[0049] The normal or first-pass direction of the metal strip 13 is
from right to left as shown in FIG. 6. The plane 19 can be used as
a reference plane for the measuring units and for the penetration
depth. A second pass, if performed, can take place in particular
from left to right, especially in the case of a tandem measuring
system.
[0050] By means of the method described above, it is possible to
describe the actual state of the metal strip in terms of its
flatness and/or its internal stresses and to make the acquired data
available to a model, which is described in a computer. The model
is then able to control and automate the straightening process. The
result of the straightening can be determined by means of a second
measurement in a second measuring unit 11, 12. The data can be used
by the model to adapt and optimize itself independently The
straightening process can be fully or partially automated,
optimized, and logged.
* * * * *