U.S. patent application number 16/427993 was filed with the patent office on 2019-09-19 for method and device for producing a metallic strip in a continuous casting and rolling process.
The applicant listed for this patent is SMS GROUP GMBH. Invention is credited to Christian MENGEL, Thomas RUNKEL.
Application Number | 20190283095 16/427993 |
Document ID | / |
Family ID | 52274102 |
Filed Date | 2019-09-19 |
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United States Patent
Application |
20190283095 |
Kind Code |
A1 |
RUNKEL; Thomas ; et
al. |
September 19, 2019 |
METHOD AND DEVICE FOR PRODUCING A METALLIC STRIP IN A CONTINUOUS
CASTING AND ROLLING PROCESS
Abstract
A method and a device for producing a metallic strip by
continuous casting-rolling, wherein a slab is cast in a casting
machine and then sent to a finishing mill located downstream,
relative to the transport direction of the strip. In the event that
the transport of the slab or strip comes to a complete or
substantially complete standstill, the following steps are carried
out: (a) cutting through the strip at a first point; (b) cutting
through the strip at a second point that is 0.1-5.0 m upstream from
the first point; (c) removing the cut-out piece of strip to create
a gap in the strip; (d) conveying new strip material into the area
of the gap from the area located upstream of the first point; and
(e) cutting off pieces of the new strip material conveyed from
upstream according to step (d) and removing the pieces from the
transport line.
Inventors: |
RUNKEL; Thomas; (Siegen,
DE) ; MENGEL; Christian; (Siegen, DE) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
SMS GROUP GMBH |
Dusseldorf |
|
DE |
|
|
Family ID: |
52274102 |
Appl. No.: |
16/427993 |
Filed: |
May 31, 2019 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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14907039 |
Jan 22, 2016 |
|
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PCT/EP2014/065979 |
Jul 24, 2014 |
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16427993 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
B21B 1/24 20130101; B21B
1/463 20130101; B22D 11/16 20130101; B21B 15/0007 20130101 |
International
Class: |
B21B 1/46 20060101
B21B001/46; B21B 1/24 20060101 B21B001/24; B21B 15/00 20060101
B21B015/00; B22D 11/16 20060101 B22D011/16 |
Foreign Application Data
Date |
Code |
Application Number |
Jul 26, 2013 |
DE |
10 2013 214 667.1 |
Aug 27, 2013 |
US |
61870507 |
Oct 14, 2013 |
DE |
10 2013 220 657.7 |
Nov 26, 2013 |
US |
61908949 |
Claims
1. A device for producing a metallic strip in a continuous
casting-rolling process, comprising: a casting machine; at least
one furnace; a first cutting device and a second cutting device for
the strip or for the slab from which the strip is produced; a
finishing mill; a cooling section; a flying shear; coiling devices;
and a central fault reporting system connected to the casting
machine, the furnace, the cutting devices, the finishing mill, the
cooling section, the flying shear and the coiling devices, and
operative to monitor their process state.
2. The device according to claim 1, wherein the fault reporting
system is configured to detect abnormalities pertaining to mass
flow in the components of the installation.
3. The device according to claim 2, wherein the fault reporting
system is configured to trigger an alarm if abnormalities lying
outside a predetermined tolerance range are detected in at least
one of the components of the installation.
4. The device according to claim 2, wherein the fault-reporting
system is configured to activate the first and/or second cutting
device as soon as abnormalities lying outside a predetermined
tolerance range pertaining to the mass flow in the components of
the installation are detected.
5. The device according to claim 1, wherein the first and/or the
second cutting device is configured to cut the strip or the slab
out of which the strip is produced at two points adjacent to each
other in the transport direction.
6. The device according to claim 5, wherein the points adjacent in
the transport direction are at least 200 mm apart.
7. The device according to claim 1, wherein at least one vertically
movable roller is arranged downstream, relative to the transport
direction, from the first and/or the second cutting device.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] The present application is a Divisional Application of U.S.
patent application Ser. No. 14/907,039, filed Jan. 22, 2016, which
is a 371 of International application PCT/EP2014/065979, filed Jul.
24, 2014, which claims priority of DE 10 2013 214 667.1, filed Jul.
26, 2013, U.S. 61/870,507, filed Aug. 27, 2013, DE 10 2013 220
657.7, filed Oct. 14, 2013, and U.S. 61/908,949, filed Nov. 26,
2013 the priority of these applications is hereby claimed and these
applications are incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] The invention pertains to a method for the production of
metallic strip by the continuous casting-rolling process, in which
a slab is first cast in a casting machine and then sent to a
finishing mill located downstream in the transport direction, where
it is rolled. The invention further pertains to a device for
producing a metallic strip.
[0003] The present invention is used in casting-rolling
installations which produce finished strip from molten metal in
endless operation. For installations of this type, an emergency
strategy is proposed for dealing with breakdowns.
[0004] Known casting-rolling lines convert molten steel to hot
strip in a compact installation. The first step is to cast a slab
of endless length.
[0005] These slabs are cut by shears into sections, the dimensions
which correspond to the desired size of the hot coil. The slabs are
conditioned to the proper temperature in heating furnaces, often
designed as roller hearth furnaces. Then the slabs are sent
individually to a rolling mill and rolled. After the strips have
been cooled in a cooling section and wound into coils, the coils
are taken from the rolling line for further processing.
[0006] In the case of the "semi-endless" method, the slab is cut in
such a way that two or more coils can be produced from it. Downline
from the rolling mill, a flying shear is also installed, which cuts
the long hot strip to obtain a coil of the desired size. With this
method, the number of critical threading-in and threading-out
operations required during rolling is reduced, which makes it
possible to produce thinner hot strips more reliably.
[0007] Common to both methods is that, because the slabs are cut
into sections, the casting process and the rolling process can be
carried out separately. The working speeds of the casting machine
and the rolling mill which can and must be used can thus be
determined independently of each other.
[0008] As a result of progress in the design of casting machines
and in process control through the use of, for example, heating
devices, it is possible today to eliminate the step of cutting the
slab into sections prior to rolling. A so-called "fully continuous"
process was developed. According to this process, the slab is
allowed to solidify completely and is then sent to the rolling mill
undivided, and all the while more molten metal is being cast onto
the same strand in the casting machine. The material is not cut
into coiling lengths until it reaches the flying shear downline
from the rolling mill.
[0009] In this fully continuous process, therefore, operating
states regularly occur in which the material forms a single
physical entity extending all the way from the casting machine to
the coiler. The entire process thus takes place continuously or in
endless fashion.
[0010] Breakdowns occur sporadically in systems of this magnitude,
which can be over several hundred meters in length. For example,
when there is a malfunction in the hot strip line or a problem with
the shears, etc., the production process must be interrupted. The
system is then stopped and all movements of the strip or of the
slab come to a standstill. It is possible for an undivided strand,
the various parts of which are in different stages of processing,
to extend over the entire length of the installation. Because this
strand can be 100 meters or more in length as it extends through
the various units (casting machine, shears, furnaces, rolling mill,
coiler), a part of the strand in one unit cannot be moved
independently of a part in another unit.
[0011] In principle, a breakdown can occur in any of the units;
that is, it can occur in the area of the coiler, of the flying
shear, of the finishing mill, of the roller hearth furnace, etc. A
disruption in the finishing mill as the result of, for example, a
tear in the strip between the last two stands thus leads within a
very short time to a backup of material between these stands, which
can be corrected only by subsequent manual operations. Several
minutes of work are required for this, and then an inspection must
be performed. Some repairs to parts of the installation may also be
necessary.
[0012] When a breakdown occurs, the control operator or the
automation system stops the rolling. The stands can usually be
opened up very quickly; all of the drives are turned off; and the
strand comes to a stop. Because the slab is not {00257009}*1
divided between this point and the mold, there are cases in which
it is also necessary to stop the casting machine.
[0013] The casting unit is especially critical in such cases. If
the shutdown lasts too long, the steel solidifies in the mold.
Removing this steel is a very difficult job, which is likely to
damage the mold. Opening the mold and the strand guides will
usually cause the strand to rupture, allowing molten steel to pour
over the unit, thus causing considerable damage. In particular, the
strand guide rollers are susceptible to thermal overload during
prolonged idle periods.
[0014] Removing the solidified cast strand from the casting machine
is very time-consuming, and often it can be done only by cutting
the strand by hand (e.g., flame cutting). Crane work is necessary
here, and the mold and possibly parts of the strand casting machine
must be replaced. This leads to very long down times and to lost
production, and it is also associated with various types of manual
operations.
[0015] EP 2 259 886 B1 proposes in this situation that the strip be
cut, that the tail end of the section of strip downstream of the
cut be bent upward, and that the strip upstream of the cut be cut
into scrap. This method is based logically on the assumption that
the upstream strip material is still moving. The method cannot be
used if the strip has already come to a complete stop, that is, if
the continuous process has already come to a standstill.
[0016] There is no known concept for dealing with a breakdown in
which the production material has already come to a complete stop.
That is, in the situation in which the production material has come
to a complete stop, there is so far no way of quickly disposing of
the production material by, for example, cutting it into scrap at
the flying or movable shear. The previous solutions assume instead
that the slab is still movable and that it is therefore possible to
move the slab through a shear to chop it up. There are various
types of breakdowns in which this is not possible, however, and it
is especially problematic when the slab or the strip has already
come to a complete stop after a production breakdown.
[0017] In light of the problems described above, the invention is
based on the goal of returning the production line to a state which
allows production to be resumed after the occurrence of a breakdown
and to do so safely, quickly, and economically, as well as
preferably partially of fully automatically. Special attention is
to be paid here to the removal of the slab or the solidifying steel
as quickly as possible from the mold and also from the casting
machine in order to minimize the possible damage and down time.
Finally, the goal is to deal with the material present in the
installation in such a way that as much of it as possible remains
suitable for further processing.
SUMMARY OF THE INVENTION
[0018] The inventive achievement of this goal is characterized in
that, in the event of a production breakdown and a complete or near
complete stoppage of the transport of the slab or strip, the
following steps are carried out:
[0019] (a) cutting through the strip at a first point;
[0020] (b) cutting through the strip at a second point, wherein the
second point is in the range of 0.1-5.0 m, and preferably of
0.2-1.0 m, upstream, relative to the transport direction, from the
first point;
[0021] (c) removing, particularly conveying away, the cut-out piece
of strip from the transport line to create a gap in the strip;
[0022] (d) conveying new strip material into the area of the gap
from the area located upstream, relative to the transport
direction, of the first point; and
[0023] (e) cutting off pieces of the new strip material conveyed
from upstream according to step (d) and removing, particularly
conveying away, the pieces from the transport line (chopping
operation).
[0024] The separating also encompasses, for example, letting the
cut strip pieces fall into an intake provided therefore.
[0025] The chopping operation also makes possible a removal of the
cast strand out of the casting machine.
[0026] The second point lies preferably upstream of the first
point.
[0027] The first and second points are preferably located between
the casting machine and the finishing mill. It is both possible and
advantageous, however, for the first and second points to be
located between a roughing mill immediately downstream from the
casting machine and a furnace downstream from the roughing mill.
The first and second points can be located between a furnace
downstream from the casting machine and the finishing mill.
[0028] The concept can be used in all types of system concepts with
desired combinations of casting machines, roughing mill, furnace,
intermediate rolling mill and finishing mills.
[0029] To make the cuts, a single separating device can be used. An
oscillating shear or a gate shear is preferred.
[0030] The above-mentioned steps (d) and (e) are preferably
repeated until the casting machine has been freed of strip material
or a section of defined length in the casting machine is free of
strip material.
[0031] According to a special procedure, the above-mentioned steps
(a)-(c) can be carried out by means of a first separating device,
and steps (d) and (e) can be carried out by means of a second
separating device, wherein the two separating devices are located
at different points relative to the transport direction.
[0032] According to a special elaboration of the method,
furthermore, the strip material is conveyed out of the finishing
mill opposite the transport direction back into the area of at
least one separating device, where pieces of the conveyed strip
material are cut off by the at least one separating device, and the
cut-off pieces are removed from the transport line (chopping
operation).
[0033] Means for applying a straightening force to the strip
material can be arranged next to the at least one separating device
to exert a force perpendicular to the surface of the strip. Thus
the tail end of the strip can be straightened in a given case.
[0034] The gap can be produced by two or possibly by more than two
cuts of the separating device.
[0035] When a furnace is present in the installation, it is also
possible to provide that, first, a gap is cut in the strand as
described, and then the strip material present in the furnace is
shortened to a desired length by means of the at least one
separating device but otherwise remains in the furnace. This makes
it possible for the shortened strip material to be held in the
furnace at a high temperature and then easily rolled out after the
problem has been corrected. In this case, the separating device is
preferably located upstream or downstream from the furnace.
[0036] The device for producing a metallic strip in the continuous
casting-rolling method comprises a casting machine, at least one
furnace, a first and a second separating device for the strip or
for the slab from which the strip is produced, a finishing mill, a
cooling section, and at least two coilers; and, according to the
invention, it provides that a central fault reporting system is
present, which is connected to the above-mentioned components of
the installation and which can monitor their process state.
[0037] The fault reporting system is in particular configured in
such a way that abnormalities pertaining to the mass flow in the
components of the installation can be detected. The fault reporting
system can be configured in particular in such a way that it can
trigger an alarm when abnormalities lying outside a predetermined
tolerance range are detected in at least one of the installation's
components. It can be configured to activate the first and/or the
second separating device as soon as abnormalities lying outside a
predetermined tolerance range pertaining to the mass flow in the
components of the installation are detected.
[0038] The first and/or the second separating device is preferably
configured so that the strip or the slab from which the strip is
produced can be cut at two points adjacent to each other in the
transport direction; these adjacent points are preferably at least
200 mm apart in the transport direction.
[0039] Downstream, relative to the transport direction, of the
first and/or the second separating device, at least one vertically
movable roller can be arranged.
[0040] The furnace is preferably configured as a tunnel furnace or
as some other type of heating device. In addition, a flying shear
can be present. The central fault reporting (problem reporting)
system covers all parts of the installation. Whenever there is a
critical mass flow problem at one of the installation's components,
an alarm is triggered, which causes all of the individual
components to stop the mass flow in a controlled manner. There is
preferably a direct connection to the first separating device, to
which a signal is transmitted for the immediate separation of the
material.
[0041] The first separating device, which is arranged downstream,
relative to the material flow direction, from the casting machine,
can cut the cast slab at two different points while it is
stationary. The scrap discharge system of this shear is preferably
large enough to accommodate all of the material present in the
strand in the material flow upstream of the first cutting device,
and the separating device can cut up a slab by means of a chopping
action.
[0042] The time between the cutting operations of the first
separating device is preferably no more than 20 seconds.
[0043] The vertically movable roller arranged downstream from the
first cutting device is provided to produce an adjustable gap
perpendicular to the transport direction of the material; by
closing the gap in the direction toward the slab, a straightening
process can be carried out at the end of the slab.
[0044] The proposed reporting system offers the advantage that an
installation is created which can be easily understood by the
operator. The entire installation is operated generally at a
constant mass flow. The central reporting system creates the
possibility of controlling the process when a problem occurs at a
subunit, and under certain conditions it can stop the process on
the basis of a defined ramp.
[0045] A direct line is connected to the first separating device.
Thus, in a given case, the material can be cut immediately, so that
the casting machine can be freed up as quickly as possible.
[0046] The cut-out parts of the slab or strip are collected in a
container. The size of the container is adapted to the requirement
that the casting machine must be emptied quickly without the need
to replace the collection buckets.
[0047] The length which is cut out--as previously mentioned--is at
least 200 mm, so that as much material as possible can removed per
unit time but also so that the separating device does not have to
be made unnecessarily large.
[0048] It is desirable to make the cutting sequence as short as
possible within the scope of the technically realizable limits and
is preferably less than 20 seconds. Thus the casting machine can be
emptied as quickly as possible.
[0049] The vertically adjustable rollers make it possible to
continue to use the slabs without causing damage to the following
components (such as the furnace) at the same time. The shape of the
knife forms an image of itself in the material; that is, a
roof-like shape is created in the slab. It is advantageous for this
elevation to be removed from the slab by means of the rollers.
[0050] According to an elaboration, it is provided that a central
fault reporting system is present and used for the entire
casting-rolling process. Problems pertaining to the entire
installation are detected and reported automatically, or a chief
operator can perform this task. After a problem pertaining to the
entire installation has been detected, the individual components
can be effectively stopped by the automation system. The sequence
of the proposed or necessary measures for eliminating the strip
material--especially from the casting machine--is preferably
carried out automatically, at least in part, by the automation
system.
[0051] The invention thus creates a method for an emergency
strategy applicable to the processing of material in a continuous
casting-rolling process, specifically for the situation in which
the cast and rolled metal strip has already come to a complete
standstill.
[0052] Advantageously, the proposed method can be used for all
cuttable strip dimensions, so they occur, for example, directly
behind the casting machine. Conventionally existing cutting devices
can be used so that no additional space is needed in the plant.
[0053] It is assumed here, therefore, that a breakdown has occurred
during fully continuous operation. The cast strand extending over
the entire length of the rolling line is in various stages of
processing. By cutting the strand and removing pieces from it
according to the invention, the sections of the strand thus
obtained are able to move through the installation again; these
strand sections can be processed further, which means that as much
material as possible remains available for further processing. The
individual units of the installation experience no significant
damage, and operation can be resumed as quickly as possible.
[0054] According to an elaboration, the measures explained above
can be carried out in parallel at different points of the
installation. For example, a first separating device can be used to
cut the strand upstream of the finishing mill and thus produce a
gap. The chopping operation, which cannot be done until after the
gap-forming cut has been made, can be carried out at a second
separating device.
[0055] During the chopping step at the separating device, the
strand is shortened until the remaining slab becomes shorter than
the length of the furnace. It can then be introduced into the
furnace for further processing; that is, the remaining slab is
loaded into the furnace so that it will be ready to be rolled as
soon as the capacity to roll has been restored.
[0056] It is preferably provided that the end of the slab is
straightened by movable rollers in the area of the shear. The
movable rollers can be arranged upstream and/or downstream of the
separating device to straighten the head and/or the tall of the
slab.
[0057] According to an elaboration of the method, the strip
material can also be conveyed in reverse from the finishing mill,
opposite the transport direction (conventional straightening of the
material), and cut by the separating device. This piece of strip
material, however, can also be conveyed from the finishing mill to
the coiler and removed from the roller table there, possibly in
association with a manual cutting operation and appropriate crane
operations.
[0058] Lowering the first roller downstream from the separating
device is advantageous as a way of assisting the first cut, i.e.,
the gap-forming cut.
[0059] The use of a scrap conveyor belt at the separating device is
also advantageous, so that the cut-off scrap can be carried away
efficiently.
[0060] The separating devices are preferably designed as
oscillating shears or as movable gate shears, which make it
especially easy to cut a gap.
[0061] Accordingly, the advantage is obtained that the ability to
operate can be restored quickly after a breakdown during endless
operation. Damage and thus down times to allow replacement of
components can thus be avoided.
[0062] It is possible to convey the strand out of the casting
machine quickly. As a result, damage to the mold and extreme
thermal load on the strand guide rollers can be avoided.
[0063] With respect to the chopping operation, the amount of strip
arriving in the transport direction during the time between two
separations corresponds to the length of strip which is cut off.
With respect to the gap-producing operation, the length of new
strip arriving in the transport direction during the time between
two separations is preferably shorter than the length which is
separated by two successive separations. The limit case with the
gap of maximum size is the situation which exists when the strip is
stationary. For this reason, it is necessary to be able to make the
cuts at different points.
[0064] The various features of novelty which characterize the
invention are pointed out with particularity in the claims annexed
to and forming a part of the disclosure. For a better understanding
of the invention, its operating advantages, specific objects
attained by its use, reference should be had to the drawings and
descriptive matter in which there are illustrated and described
preferred embodiments of the invention.
BRIEF DESCRIPTION OF THE DRAWINGS
[0065] FIG. 1 shows a schematic diagram of a casting-rolling
installation for the production of steel strip;
[0066] FIG. 2 shows a section of the strip with a separating device
in the form of an oscillating shear during a first substep of the
proposed method;
[0067] FIG. 3 shows the section of the strip with the separating
device during a second substep of the proposed method;
[0068] FIG. 4 shows the section of the strip with the separating
device during a third substep of the proposed method;
[0069] FIG. 5 shows the section of the strip with the separation
device during a fourth substep of the proposed method;
[0070] FIG. 6 shows the section of the strip with the separation
device during a fifth substep of the proposed method;
[0071] FIG. 7 shows the section of the strip with the separation
device during a sixth substep of the proposed method;
[0072] FIG. 8 shows the section of the strip with the separation
device during a seventh substep of the proposed method;
[0073] FIG. 9 shows the section of the strip with the separation
device during an eighth substep of the proposed method;
[0074] FIG. 10 shows the section of the strip with the separation
device during a ninth substep of the proposed method; and
[0075] FIG. 11 shows the section of the strip with the separation
device during a tenth substep of the proposed method.
DETAILED DESCRIPTION OF THE INVENTION
[0076] FIG. 1 shows a sketch of an example of a casting-rolling
installation, which is designed as a fully continuous installation
and which comprises as its central elements a casting machine 2 and
a finishing mill 3. Downstream from the casting machine 2 is a
roughing mill 7, to which, depending on the plant design, a furnace
8 (connecting roller table with heating function) is connected.
[0077] Downstream from the furnace 8 is the finishing mill 3.
Downstream from the finishing mill 3 is a cooling section 12 and a
flying shear 13. Next in the transport direction F is at least one
coiler 14, 15.
[0078] Between the roughing mill 7 and the furnace 8, a first
separating device 9 for the strip 1 in the form of an oscillating
shear is arranged. A second separating device 10 of the same type
is located between the furnace 8 and the finishing mill 3.
[0079] Naturally, the proposed method can also be used in a
different type of casting-rolling installation.
[0080] By the use of sensors (not shown), the complete installation
is monitored by a central fault reporting system 16.
[0081] During endless rolling, the installation is completely
filled by a strand, that is, by a continuous strip 1. When a
breakdown occurs, the strand or the strip comes to a stop. Because
of the length of the installation, the operating personnel cannot
see the entire line. A problem occurs in only one part of the
installation and usually triggers an immediate stop of this part.
This leads to an uncontrolled backup of material or to traction on
the material in the other parts of the installation if a controlled
stop at a suitable deceleration rate is not initiated in these
other parts. As a result, damage can be caused to various parts of
the installation. In addition, a material backup can develop, and
until it has been corrected it is impossible for production to
continue.
[0082] Because all of the parts of the installation are connected,
stopping the material means that the entire strand or strip 1 can
no longer move. According to the invention, a gap is intentionally
produced, so that the slab will be able to move again. In addition,
the casting machine 2 must be freed of material as quickly as
possible so as not to "freeze". It should also be possible to send
as much as possible of the still-usable material present in the
installation to further processing.
[0083] The inventive solution proceeds on the basis of the
following units in the installation:
[0084] As described above, the installation is configured
essentially as shown in FIG. 1. A typical element of a fully
continuous casting-rolling installation of this type is the central
fault reporting system 16 and the separating devices 9, 10, and
13.
[0085] All of the fault reports are collected in the higher-level
central fault reporting system 16, so that the necessary measures
can be implemented effectively in the concrete case.
[0086] The separating device 9 situated upstream relative to the
transport direction F is designed as, for example, an oscillating
shear or a movable gate shear. The separating device 9 has the
property of being able to make, in a short time, several separating
cuts in stationary and/or moving material at positions within the
separating device which differ in the transport direction. The
separating device also comprises a scrap discharge system 17 (see,
for example, FIG. 2).
[0087] It is advantageous into another separating device 10, which
is arranged downstream from the furnace 8 and upstream from the
finishing mill 3; this separating device 10 is therefore downstream
from the separating device 9 in the production line, but it can be
designed in exactly the same way as the separating device 9,
including the scrap discharge system 17.
[0088] Devices are provided in the casting machine 2, furthermore,
which make it possible to bring the casting process to a standstill
quickly and which allow the cast strand to be transported again
after a defined maximum period of time.
[0089] The central fault reporting and response system 16, which it
is advantageous to provide, covers the entire installation. If, for
example, a material flow problem occurs in the finishing mill 3 or
if such a problem becomes evident, a signal must be transmitted
immediately to all of the other units and controls in the
installation, so that the individual units and drives can be
stopped simultaneously in a controlled manner.
[0090] After the signal "fault" has been sent, the casting machine
2 is also stopped in a controlled manner; that is, no more molten
steel may be allowed to enter the mold, and the machine must be
brought to a standstill.
[0091] A fault is detected either by suitable sensors (speed
indicators, strip tension meters, loop lifters, etc.) of the
installation's automation system or by the operating personnel in
one of the areas of the installation.
[0092] The proposed method and the installation equipment necessary
to implement it are provided to allow the separation of a
stationary or nearly stationary material strand (transport speed of
less than 1 m/min) in a short time and thus to make it possible to
empty the casting machine 2.
[0093] The specific sequence of steps of the method is illustrated
by way of example in FIGS. 2-11. The essential idea here is to
create the possibility of cutting a gap in the stationary material
or strip 1. This gap makes it possible to resume the transport of
the strip, so that the strip material can be chopped into scrap and
removed from the installation.
[0094] FIG. 2 shows a separating device 9, 10. This could
represent, for example, the second separating device 10. The
separating device is designed as an oscillating shear.
[0095] The shear carrier 18 of the oscillating shear 10 is first
pivoted as illustrated in FIG. 2 (around an axis perpendicular to
the plane of the drawing in FIG. 2), so that the shearing elements
19 and 20 are located at a first point 4 of the installation. The
strip 1 is completely at rest here; that is, the transport speed in
the transport direction is therefore, in practice, zero.
[0096] In FIG. 3 we see how the shearing elements 19, 20 have been
moved toward each other to cut through the strip 1 at the first
point 5. The shearing elements 19, 20 are then moved back away from
each other again--as shown in FIG. 4; the strip 1 is now separated
at the first point 4.
[0097] Now, as can be seen in FIG. 5, the shear carrier 18 is
pivoted so that the shear elements 19, 20 arrive at a second point
5 of the installation. Now, according to FIG. 6, another cut is
made, and thus a piece 21 of strip is cut away from the strip 1.
The first and second points 5, 4 are usually 0.2-1.5 m apart from
each other.
[0098] This piece 21 falls down into the area of a scrap discharge
system 17 (shown only in highly schematic fashion), as can be seen
in FIG. 7. A gap 6 remains in the strip 1.
[0099] The strip 1 can now travel from the left into the gap 6 thus
created, while the strip 1 on the right remains at rest. This is
illustrated in FIG. 8. The strip is fed from the casting machine 2
into the gap at a creep, and thus the chopping operation starts, by
which the strip 1 coming from the left is cut into pieces 21 and
then removed from the area of the casting machine 2.
[0100] As can be seen in FIG. 9, another piece 21 is cut out after
a sufficient amount of strip, coming from the left, has arrived in
the area of the gap 6. After the piece 21 has been cut off, as can
be seen in FIG. 10, the gap 6 is again available for the
chopping-off of additional strip material.
[0101] The chopping process continues until the strip or slab
coming from the casting machine 2 has been cut into pieces 21 and
removed by the scrap discharge system 17. In this way, the casting
machine 2 is freed of strip material, and as much of the remaining
slab as desired is removed.
[0102] It can be seen in FIG. 11, furthermore, how the tail end of
the still-stationary strip 1 can be straightened in the area on the
right of the figure. For this purpose, means 11 for applying a
straightening force are provided, so that the tail end of the strip
can be straightened. The central part of the means 11 consists of
vertically movable rollers, which can press against the surface of
the strip.
[0103] Depending on the design of the casting installation, the
casting process can now resume.
[0104] The separating devices 9, 10 can be used alternatively or
additively as described.
[0105] As a combination variant of the method, it is also possible
for the separating device 10 to cut the gap 6, whereas the
remaining strand proceeding from the casting machine 2 is chopped
into scrap at the separating device 9 and removed by the scrap
removal system there.
* * * * *