FEED OPENING ADJUSTMENT OF SEGMENTS FOR CONTINUOUS CASTING SYSTEMS

REGLAGE D'OUVERTURE D'ENTREE DE SEGMENTS D'INSTALLATIONS DE COULEE CONTINUE

English Abstract

The invention relates to a method for adjusting the feed opening of segments
for continuous casting systems, especially position-controlled segments for
slab and thin-slab continuous casting systems which comprise a strand guide
(1) with segments (2) for a predetermined guidance of a cast strand using
measuring and control signals. In order to provide an independent intelligent
segment, the measuring and control signals are processed in at least one
system unit (14) directly on the respective segment (2) and the set values are
fed to the segment (2) by a superordinate control system (10) via a field bus
(11), for example a profibus and a power supply (12). Actual values are
returned to the control system (10) via the field bus (11) as the result of
control or as a process status. The system units (14) present on the segment
(2) are supplied with segment-specific data such as rigidity coefficients,
roller diameter, control parameters, feed opening basic settings and
adjustment quota. The invention also relates to a device for carrying out the
method.

French Abstract

L'invention concerne un procédé de réglage d'ouverture d'entrée de segments d'installations de coulée continue, notamment de segments de position réglée d'installations de coulée continue à brames et à brames minces, comprenant un guide de billette (1) doté de segments (2) et destiné au guidage déterminé d'une billette à l'aide de signaux de mesure et de réglage, afin d'obtenir un segment intelligent indépendant de telle manière que les signaux de mesure et de réglage soient traités dans au moins une unité système (14) située directement dans le segment concerné (2) ; que les données valeur théorique soient cédées au segment (2) par un système de commande hiérarchiquement supérieur (10) via un bus de terrain (11), par exemple un bus de terrain de processus, et un dispositif d'alimentation en courant (12) et que les données valeur réelle soient renvoyées au système de commande (10) sous forme de résultat de réglage ou d'état de processus également via le bus de terrain (11). Des informations spécifiques au segment telles que des coefficients de rigidité, des diamètres de rouleaux, des paramètres de réglage, des réglages de base d'ouvertures d'entrées et des taux de réglage sont cédées aux unités système (14) situées sur le segment (2). L'invention concerne également un dispositif permettant de mettre en oeuvre ce procédé.

Claims

CLAIMS
1. Device for automatically controlling the feed opening
of segments for continuous casting plants, which are designed
at least with an associated position sensor (7) and an
associated pressure sensor (8), especially for automatically
controlling the feed opening of segments for slab and thin-slab
continuous casting plants, which comprise a strand guide (1)
with segments (2) for predetermined guidance of a cast strand
with the use of measuring signals and automatic control
signals, characterized by the fact that each segment (2) has at
least one decentralized system unit (14) operable to
communicate with said associated position and pressure sensors
for processing said measuring and automatic control signals,
and wherein the at least one decentralized system unit is
connected via one of a field bus and profi bus (11) with an
overriding control system (10) and a power supply (12) wherein
the control system is operable to communicate predetermined set
point values to the at least one system unit.
2. Device in accordance with claim 1, characterized by
the fact that the lines for bus links (11) and for the power
supply (12) are equipped with plug connections for the purpose
of making segment changes.
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3. Device in accordance with Claim 1 or Claim 2,
characterized by the fact that the system units (14) are
automatic control and regulation units.
4. Device in accordance with any one of Claims 1 to 3,
characterized by the fact that the system units (14) comprise
intelligent terminals.
5. Use of the device for automatically controlling the
feed opening of segments for continuous casting plants,
especially segments for slab and thin-slab continuous casting
plants, in accordance with any one of Claims 1 to 4,
characterized by the fact that the measuring and automatic
control signals are processed in the at least one decentralized
system unit (14) directly on the given segment (2), the
predetermined set point values are fed to the segment (2) by
the overriding control system (10) via one of said field bus
(11), and profi bus, and said power supply (12); wherein actual
values are returned to the control system (10) via one of said
field bus (11) and profi bus as control results or as a process
status.
6. Use of the device in accordance with Claim 5,
characterized by the fact that segment-specific data selected
from the group consisting of modulus of elasticity in shear,
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roller diameter, automatic controller parameters, basic
settings of the feed opening and adjustment ratios, are
supplied to the system units (14) located on the segment (2).
7. Use of the device in accordance with Claim 5 or Claim
6, characterized by the fact that, besides the necessary
function(s) for accomplishing the segment adjustment, the
decentralized system unit (14) is assigned additional
decentralized segment-specific functions selected from the
group consisting of acquisition and processing of other
measurement data, bearing force monitoring, temperature
measurements, temperature controls and calibration data.
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Description

CA 02469641 2004-06-08
Translated Text of WO 03/051,558 A2 (PCT/EP02/12693)
with Amended Claim Incorporated Therein
Feed Opening Adjustment of Segments for Continuous
Casting Systems
The invention concerns a device for automatically
controlling the feed opening of segments for continuous casting
plants, which are designed at least with a position sensor and a
pressure sensor, especially for automatically controlling the
feed opening of segments for slab and thin-slab continuous
casting plants, which comprise a strand guide with segments for
predetermined guidance of a cast strand with the use of
measuring signals and automatic control signals. The invention
also concerns the use of the device.
The prior art includes position-controlled and pressure-
controlled segments (segment cylinders) in continuous casting
plants. In the prior art, the feed opening is adjusted by
hydraulic cylinders and measuring/automatic control devices and
regulation devices that can be assigned to them, especially for
use in soft-reduction (SR) and liquid-core-reduction (LCR)
processes.
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The automatic control and regulation devices necessary for
this are usually located in remote switching equipment of the
continuous casting plants.
The automatic control and/or regulation breaks down if
there is a failure of the transmission devices or transmission
lines.
The document DE 100 28 304 Al discloses a method and a
device for decentralized casting data processing of the
measurement data acquired by sensors at a continuous casting
mold in a process computer of a continuous casting plant. This
previously known development is based on the objective of more
efficient electronic processing of, among other things, the
casting data measured by sensors and on the further objective of
using this more efficient electronic processing to simplify the
equipment provided for this purpose. To this end, the measuring
and control data are collected in cooled field bus modules
directly on the continuous casting mold and converted to bus
signals in a bus line and at least stored and/or processed in
the control system of the continuous casting plant. This
greatly reduces and simplifies the data flow path and also
simplifies the equipment.
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Another advantage of this development results from the fact
that mold-specific information, e.g., on the thickness of the
copper plates, the degree of erosion, the condition of the heat
sensors and/or the resistance heat sensors, and the maintenance
cycles, can be stored in and retrieved from the field bus
modules on the continuous casting mold.
The document WO 99/46,071 discloses an adjustment method
for a roller segment of a continuous casting plant, which has a
segment inlet side, a segment outlet side, and a pair of roller
supports, each of which supports at least two rollers that
extend over a support area. The roller supports are mutually
adjusted by an adjusting unit installed on the segment inlet
side and another installed on the segment outlet side. Each
adjusting unit has two hydraulic cylinder units installed on
either side of the support area.
In the adjustment method known from this document, the
hydraulic cylinder units can be adjusted by both position
control and pressure control, the rollers can be adjusted by the
hydraulic cylinder units via position control to a strand of
metal guided by the rollers, and the hydraulic cylinder units
can be switched from position-controlled to pressure-controlled
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operation if the pressure in the given hydraulic cylinder
unit reaches a limit value.
Proceeding on the basis of the aforementioned prior
art, the objective of the invention is to install a
decentralized automatic control and regulation system with
suitable modules directly on a segment or directly on a
hydraulic cylinder to create an "intelligent" segment that
ensures continued operation even in the event of a loss of
communication data.
In accordance with the invention, this objective is
achieved with a device in which each segment has at least
one decentralized system unit, which is connected with an
overriding control system and a power supply via a field bus
or profi bus.
Besides a design of the system unit with control and
regulation units on the segment, an alternative design with
so- called intelligent terminals on the segment to reduce the
amount of cabling is possible.
With respect to the use of the device of the invention, it
is proposed that the measuring and automatic control signals are
processed in at least one system unit directly on the given
segment, the predetermined set point values are fed to the
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segment by an overriding control system via a field bus, e.g., a
profi bus, and actual values are returned to the control system,
likewise via the field bus, as control results or as the process
status.
With respect to the use of the invention, it is further
provided that, besides the necessary function(s) for
accomplishing the segment adjustment, the decentralized system
unit is assigned additional decentralized segment-specific
functions, such as acquisition and processing of other
measurement data, e.g., bearing force monitoring, temperature
measurements and controls, and calibration data.
The measures in accordance with the invention enable the
segment, even in the event of loss of communication with the
control system, to independently control the data that has been
set or the data stored in the control module, e.g., for the
desired position or for the desired force value that has been
set. The battery unit required for bridging the communication
failure is also located on the segment.
Another advantage that is gained at the same time is a
reduction of the electric plug connections between the segment

CA 02469641 2010-03-17
and the control system, which results in a reduction of the
segment changing times.
In one aspect of the present invention, there is
provided a device for automatically controlling the feed
opening of segments for continuous casting plants, which
are designed at least with a position sensor and a pressure
sensor, especially for automatically controlling the feed
opening of segments for slab and thin-slab continuous
casting plants, which comprise a strand guide with segments
for predetermined guidance of a cast strand with the use of
measuring signals and automatic control signals,
characterized by the fact that each segment has at least
one decentralized system unit, which is connected via a
field bus or profi bus with an overriding control system
and a power supply.
In another aspect of the present invention, there is
provided a device for automatically controlling the feed
opening of segments for continuous casting plants, which are
designed at least with an associated position sensor and an
associated pressure sensor, especially for automatically
controlling the feed opening of segments for slab and thin-
slab continuous casting plants, which comprise a strand
guide with segments for predetermined guidance of a cast
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strand with the use of measuring signals and automatic
control signals, characterized by the fact that each segment
has at least one decentralized system unit operable to
communicate with said associated position and pressure
sensors for processing said measuring and automatic control
signals, and wherein the at least one decentralized system
unit is connected via one of a field bus and profi bus with
an overriding control system and a power supply wherein the
control system is operable to communicate predetermined set
point values to the at least one system unit.
An embodiment in accordance with the state of the art is
described below with reference to Figure 1, and an embodiment
of the object of the invention is described with reference to
Figure 2.
Figure 1 shows a strand guide 1 of well-known design,
which comprises a number of strand guide segments 2, which
safely guide the strand 3 from the point at which it leaves
the mold with increasing solidification through the areas of
soft reduction or liquid core reduction.
The segments 2 (shown enlarged) are provided with
hydraulic adjusting devices, which in turn are equipped with
a position sensor 7 and preferably a pressure sensor 8. These
are position-controlled and pressure-controlled segments 2,
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whose feed openings and position can be adjusted by means of
hydraulic cylinders and associated measuring/automatic
control devices and regulation devices according to
predetermined set points. The automatic control system for
this is located in remote equipment or switching stations 4 of
the continuous casting plant.
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In contrast to the state of the art, the embodiment of the
strand guide in accordance with the invention, which is equipped
at least with an independent position sensor 7 and pressure
sensor 8 and is preferably connected by a bus link 11 or a profi
bus with an overriding control system 10 and a power supply 12.
The lines present for this with plug connections 13 require only
a fraction of the line system 5 with plug connections 6 in the
state-of-the-art embodiment shown in Figure 1. Another decisive
advantage results from the fact that in the event of a failure
of the transmission lines or connection devices, the automatic
control or regulation does not break down due to its self-
sufficient position on the segments. Instead of the automatic
control and regulation units on the segment 2, so-called
intelligent terminals can be provided as an advantageous
alternative solution.
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List of Reference Numbers
1 strand guide
2 segment
3 cast strand
4 central control
lines
6 plug connections of (5)
7 position sensor
8 pressure sensor
9 liquid core in the strand
control system
11 field bus/profi bus
12 power supply
13 plug connections in 11/12
14 decentralized automatic controller
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Representative Drawing