EP0120338A1 - Method for detecting the wear of the wall of a mould during continuous casting and for detecting the removal of the strand shell from the internal wall of the mould - Google Patents

Method for detecting the wear of the wall of a mould during continuous casting and for detecting the removal of the strand shell from the internal wall of the mould Download PDF

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Publication number
EP0120338A1
EP0120338A1 EP84102183A EP84102183A EP0120338A1 EP 0120338 A1 EP0120338 A1 EP 0120338A1 EP 84102183 A EP84102183 A EP 84102183A EP 84102183 A EP84102183 A EP 84102183A EP 0120338 A1 EP0120338 A1 EP 0120338A1
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European Patent Office
Prior art keywords
mold
wall
strand
distance
sensor
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EP84102183A
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German (de)
French (fr)
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EP0120338B1 (en
Inventor
Gerhard Stadtfeld
Burkhard Dr. Christmann
Jörg Dr. Weber
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Licentia Patent Verwaltungs GmbH
Vodafone GmbH
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Licentia Patent Verwaltungs GmbH
Mannesmann AG
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Priority to AT84102183T priority Critical patent/ATE25016T1/en
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B22CASTING; POWDER METALLURGY
    • B22DCASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
    • B22D11/00Continuous casting of metals, i.e. casting in indefinite lengths
    • B22D11/16Controlling or regulating processes or operations

Definitions

  • the invention relates to a device according to the preamble of claim 1 and to the use thereof for determining the lifting of the strand shell from the inner wall of the mold.
  • the strand In the continuous casting of metals, the strand is produced by continuously pouring liquid material through a chute of the mold. As it exits the shaft, the strand consists of a solid shell and a liquid core. Further cooling outside the mold leads to complete solidification.
  • a system-specific limit value eg 10 mm
  • the strand shell heats up again by supplying heat from the liquid strand core and expands at most until it touches the cooled shaft wall again.
  • This process can be repeated several times in a strand cross-section as it passes through the mold, the position and size of the withdrawals in the shaft varying over time.
  • the gaps between the shaft wall and the strand created by the withdrawals are partially filled - especially with small withdrawals (casting powder).
  • the reduction in strand cooling by lifting weakens the shell growth in the mold and can cause disturbances in the casting process, in particularly severe cases even strand breaks. Therefore, the mold shaft is designed conically for a global consideration of the shrinkage of the strand shell. Taper is a critical parameter. If the taper is too low, the cooling can be reduced by lifting off, if the taper is too large, the friction between the strand and the shaft walls in the lower shaft area can become too great. For a large part of the casting programs there are empirical values that allow a satisfactory casting process.
  • the invention has for its object to provide a device with which the wear of the mold walls can be determined during the casting process, the lifting of the strand from the walls can also be determined from the result.
  • the type of use of the device according to claim 1 for determining the lifting of the strand shell from the mold inner wall is indicated by the features of the characterizing part of claim 2.
  • the device according to the invention and its use is explained in more detail in the exemplary embodiments described below with reference to the drawing.
  • FIG. 1 shows a mold with measuring sensors mounted in bores sensors
  • Figure 2 shows a mold wall with a measuring sensor in a through hole and a measuring sensor that measures in the area of critical wear.
  • FIG. 3 shows a mold wall with a measuring sensor in a through hole and a measuring sensor that measures in the area of critical wear.
  • Fig. 1 are installed in a shaft wall 1 of the mold in openings 4,4 'eddy current distance sensors 3,3'.
  • the sensors are so far away from the strand surface 2 that it does not touch the sensors even when the mold wall is allowed to wear to the maximum.
  • L the distance between the shaft surface and sensors is given and known through the installation. This distance is denoted by L; it corresponds to zero mold wear, i.e. not worn out.
  • each distance measuring sensor determines the current distance A of the strand surface from the sensor and leads this to the elimination of the influence (temporary) lifting of the strand from the shaft walls of a minimum value memory assigned to it, which is the smallest in the measured value supplied while deleting the last stored value saves.
  • the sensors can also be designed so that they only measure distance values in the area of critical wear with sufficient accuracy, cf. See Fig. 2. This enables a smaller and simpler design 5 in eddy current measuring sensors.
  • the measuring sensor opening 6 only has to be so deep that there is no more wall material (usually copper) between the measuring sensor 5 and the surface of the strand only when the wear values are critical. So that the strand is not mechanically stressed by the opening 4 required for the sensor in the mold wall, the space between the sensor surface and the mold wall is filled with a non-magnetic, electrically non-conductive material 7, which has similar mechanical abrasion properties as the mold wall.
  • a significant improvement in the casting process is achieved by tracking the shaft walls to the nominal geometry of the shaft, in which the measured wear values are fed to an adjusting device which shifts the mold walls in accordance with these values.
  • the conicity of the narrow surfaces of the mold shaft which is particularly important for the process, can be kept at the required value, particularly in the case of continuous slab casting plants.
  • the device for determining the mold wall wear according to the invention is used to determine the lifting of the strand shell from the mold inner wall.
  • a characteristic variable is determined from the measured lift-off values, which is fed to one or the conicity adjustment device mentioned above for the corresponding adjustment of the mold wall. This parameter is obtained by storing the maximum value of the lift-off values.
  • the target values for the mold wall adjustment are determined with the aid of a computer from the measured values of the device, taking into account the relevant plant parameters (strand length, take-off speed).
  • the measuring heads 8 are coupled directly to the mold wall 1.
  • the pulse-echo method is used.
  • the wear of the mold wall results from the transit time of the sound pulse reflected on the shaft surface.
  • the reflection is influenced by the strand surface and the "lubricant layer" 9 between the strand and shaft surface and can at times become very small.
  • a minimum value storage is therefore carried out here - analogous to the previous exemplary embodiment.
  • a determination of the strand lift-off is possible with sound if the space between the strand surface and the shaft is completely filled with casting powder.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Continuous Casting (AREA)
  • Measurement Of Length, Angles, Or The Like Using Electric Or Magnetic Means (AREA)
  • Length Measuring Devices With Unspecified Measuring Means (AREA)

Abstract

An apparatus for determining the wear of a mold wall during continuous casting of metal by using at least one distance measuring sensor disposed in the mold wall to measure the instantaneous distance from the sensor to the casting. The surface of the casting adjacent the mold wall may be irregular, so the minimum value of the distance between the sensor and casting is stored and used as the current distance between the sensor and the inner mold wall. Mold wear is determined by subtracting the current distance between the sensor and the inner mold wall from the original distance, before the abrasive casting process began. The sensor signals are also used to determine when the mold geometry should be adjusted to compensate for the wear. This is accomplished by storing the maximum distance between the sensor and casting and subtracting the current distance from this maximum, since the maximum distance increases as the casting shrinks away from the mold wall.

Description

Die Erfindung bezieht sich auf eine Vorrichtung gemäß dem Oberbegriff des Patentanspruchs 1 sowie auf die Verwendung derselben zur Ermittlung der Abhebung der Strangschale von der Kokilleninnenwand.The invention relates to a device according to the preamble of claim 1 and to the use thereof for determining the lifting of the strand shell from the inner wall of the mold.

Beim Stranggießen von Metallen wird der Strang durch kontinuierliches Gießen von flüssigem Material durch einen Schacht der Kokille erzeugt. Beim Austreten aus dem Schacht besteht der Strang aus einer festen Schale und einem flüssigen Kern. Weitere Kühlung außerhalb der Kokille führt zur vollständigen Erstarrung.In the continuous casting of metals, the strand is produced by continuously pouring liquid material through a chute of the mold. As it exits the shaft, the strand consists of a solid shell and a liquid core. Further cooling outside the mold leads to complete solidification.

Reibung zwischen Strang und Schachtwänden führt zu einem Abrieb an den Wänden (beim Stahlbrammen-Stranggießen etwa 0,5 mm in 10 Betriebsstunden). Überschreitet die dadurch bedingte Abnahme der Stärke der Schachtwände einen anlagenspezifischen Grenzwert (z.B. 10 mm), so muß die Kokille ausgetauscht werden. Derzeit wird die Abnahme der Wandstärke während der Gießpausen ermittelt. Wegen der starken Zunahme der maximalen Gießzeiten in den letzten Jahren ist eine Feststellung der Abnutzung während der Gießprozesse von großer Bedeutung. Eine solche Feststellung wird durch das zeitlich und örtlich variierende "Abheben" des Stranges von den Kokillenwänden sehr erschwert. Das Abheben wird durch Schrumpfen des Strangquerschnittes bei der Abkühlung der Strangschale durch Kontakt mit den gekühlten Kokillenwänden verursacht. Nach dem Abheben erwärmt sich die Strangschale durch Wärmezufuhr aus dem flüssigen Strangkern wieder und dehnt sich maximal so weit aus, bis sie wieder die gekühlte Schachtwand berührt. Dieser Vorgang kann sich in einem Strangquerschnitt beim Durchgang durch die Kokille mehrfach wiederholen, wobei Lage und Größe der Abhebungen im Schacht zeitlich variieren. Die durch die Abhebungen entstehenden Spalte zwischen Schachtwand und Strang sind teilweise - insbesondere bei kleinen Abhebungen - gefüllt (Gießpulver).Friction between the strand and the shaft walls leads to abrasion on the walls (in steel slab continuous casting, about 0.5 mm in 10 operating hours). If the resulting decrease in the thickness of the shaft walls exceeds a system-specific limit value (eg 10 mm), the mold must be replaced. The decrease in wall thickness is currently being determined during the casting breaks. Because of the sharp increase in maximum casting times in recent years, it is very important to determine wear during the casting processes. Such a finding is very much due to the "lifting" of the strand from the mold walls, which varies in time and location difficult. Lifting is caused by the shrinkage of the strand cross-section when the strand shell cools down due to contact with the cooled mold walls. After lifting off, the strand shell heats up again by supplying heat from the liquid strand core and expands at most until it touches the cooled shaft wall again. This process can be repeated several times in a strand cross-section as it passes through the mold, the position and size of the withdrawals in the shaft varying over time. The gaps between the shaft wall and the strand created by the withdrawals are partially filled - especially with small withdrawals (casting powder).

Die Verringerung der Strangkühlung durch Abheben schwächt das Schalenwachstum in der Kokille und kann Störungen des Gießprozesses hervorrufen, in besonders krassen Fällen sogar Strangdurchbrüche. Daher ist für eine globale Berücksichtigung der Schrumpfung der Strangschale der Kokillen-Schacht konisch ausgeführt. Die Konizität ist ein kritischer Parameter. Bei zu geringer Konizität kann die Minderung der Kühlung durch Abhebung, bei zu großer Konizität die Reibung zwischen Strang und Schachtwänden im unteren Schachtbereich zu groß werden. Für einen großen Teil der Gießprogramme liegen Erfahrungswerte vor, die einen befriedigenden Gießablauf erlauben.The reduction in strand cooling by lifting weakens the shell growth in the mold and can cause disturbances in the casting process, in particularly severe cases even strand breaks. Therefore, the mold shaft is designed conically for a global consideration of the shrinkage of the strand shell. Taper is a critical parameter. If the taper is too low, the cooling can be reduced by lifting off, if the taper is too large, the friction between the strand and the shaft walls in the lower shaft area can become too great. For a large part of the casting programs there are empirical values that allow a satisfactory casting process.

In diesen Fällen ist die kontinuierliche Überprüfung der Abnutzung der Schachtwände und gegebenenfalls eine die Abnutzung kompensierende Nachstellung der Wände von großer Bedeutung. Für besonders kritische Gießaufgaben sind jedoch Messungen von Abhebungen in der Kokille und Einstellung der Konizität nach diesen Werten erforderlich. Das gilt insbesondere bei stark variierenden Gießgeschwindigkeiten. Eine Messung der Abhebung war bisher nicht möglich.In these cases, it is very important to continuously check the wear of the shaft walls and, if necessary, readjust the walls to compensate for the wear. For particularly critical casting tasks, however, measurements of withdrawals in the mold and adjustment of the taper according to these values are required. This is especially true when casting speeds vary widely. Up until now it was not possible to measure the withdrawal.

Es ist durch die DE-OS 31 10 012 eine Anordnung bekanntgeworden, bei der durch einen Fühler unterhalb und damit außerhalb der Kokille die Änderung des Abstandes zur Strangoberfläche festgestellt wird. In Abhängigkeit von dieser Änderung wird die Konizität der Kokille während des Gießprozesses nachgestellt. Durch diese Anordnung wird aber die Abnutzung der Kokillenwand nicht erfaßt. Daher ist auch eine optimale Nachstellung der Konizität nicht möglich. Außerdem sind Probleme durch Ausdehnung des Stranges nach Verlassen der Kokille zu erwarten, so daß nicht sicher unterschieden werden kann, ob eine Änderung des Abstandes Strangoberfläche - Sensor durch Änderung der Strangabhebung in der Kokille oder der Ausbauchung des Stranges außerhalb der Kokille hervorgerufen wird.An arrangement has become known from DE-OS 31 10 012, in which the change in the distance to the strand surface is determined by a sensor below and thus outside the mold. Depending on this change, the taper of the mold is adjusted during the casting process. With this arrangement, however, the wear of the mold wall is not recorded. Therefore, an optimal adjustment of the taper is not possible. In addition, problems due to expansion of the strand after leaving the mold are to be expected, so that it cannot be reliably distinguished whether a change in the distance between the surface of the strand and the sensor is caused by changing the strand lift in the mold or the bulging of the strand outside the mold.

Der Erfindung liegt die Aufgabe zugrunde, eine Vorrichtung anzugeben, mit der während des Gießprozesses die Abnutzung der Kokillenwände ermittelt werden kann, wobei aus dem Ergebnis auch die Abhebung des Stranges von den Wänden festgestellt werden kann.The invention has for its object to provide a device with which the wear of the mold walls can be determined during the casting process, the lifting of the strand from the walls can also be determined from the result.

Gemäß der Erfindung wird die Aufgabe der Feststellung der Abnutzung der Kokillenwände durch die im Kennzeichen des Patentanspruchs 1 aufgeführten Merkmale gelöst.According to the invention the object of determining the wear of the mold walls is achieved by the features listed in the characterizing part of patent claim 1.

Die Art der Verwendung der Vorrichtung gemäß Patentanspruch 1 zur Ermittlung der Abhebung der Strangschale von der Kokilleninnenwand wird durch die Merkmale des Kennzeichens des Patentanspruchs 2 angegeben. Die Vorrichtung gemäß der Erfindung und ihre Verwendung wird in den nachstehend beschriebenen Ausführungsbeispielen an Hand der Zeichnung näher erläutert.The type of use of the device according to claim 1 for determining the lifting of the strand shell from the mold inner wall is indicated by the features of the characterizing part of claim 2. The device according to the invention and its use is explained in more detail in the exemplary embodiments described below with reference to the drawing.

Ein Ausführungsbeispiel mit Wirbelstrom-Abstandssensoren wird an Hand der Figuren 1 und 2 beschrieben. Figur 1 zeigt eine Kokille mit in Bohrungen angebrachten Meßsensoren, die Figur 2 eine Kokillenwand mit einem Meßsensor in einer durchgehenden Bohrung und einem Meßsensor, der im Bereich der kritischen Abnutzung mißt. Ein weiteres Ausführungsbeispiel mit Ultraschall-Meßsensoren wird an Hand der Figur 3 beschrieben.An exemplary embodiment with eddy current distance sensors is described with reference to FIGS. 1 and 2. FIG. 1 shows a mold with measuring sensors mounted in bores sensors, Figure 2 shows a mold wall with a measuring sensor in a through hole and a measuring sensor that measures in the area of critical wear. Another embodiment with ultrasonic measuring sensors is described with reference to FIG. 3.

In der Fig. 1 sind in einer Schachtwand 1 der Kokillle in Öffnungen 4,4' Wirbelstrom-Abstandsmeßsensoren 3,3' eingebaut. Die Sensoren sind dabei so weit von der Strangoberfläche 2 entfernt, daß diese auch bei maximal erlaubter Abnutzung der Kokillenwand die Sensoren nicht berührt. Bei einer noch nicht benutzten Kokille ist der Abstand Schachtoberfläche - Sensoren durch den Einbau gegeben und bekannt. Dieser Abstand sei mit L bezeichnet; er entspricht einer Kokillenabnutzung von Null, d.h. nicht abgenutzt. Während des Gießens ermittelt jeder Abstandsmeßsensor den jeweils aktuellen Abstand A der Strangoberfläche zum Sensor und führt diesen zur Eliminierung des Einflusses (zeitweiser) Abhebungen des Stranges von den Schachtwänden einem ihm zugeordneten Minimalwertspeicher zu, der jeweils den kleinsten im zugeführten Meßwert unter Löschung des zuletzt gespeicherten Wertes speichert. Der momentane Wert der Abnutzung der Schachtwand ergibt sich aus dem gespeicherten Abstandswert A' zu A L = L - A'. Aus den AL-Werten der eingesetzten Sensoren folgt, wann die Kokille ausgetauscht und gegebenenfalls das Gießen abgebrochen werden muß.In Fig. 1 are installed in a shaft wall 1 of the mold in openings 4,4 'eddy current distance sensors 3,3'. The sensors are so far away from the strand surface 2 that it does not touch the sensors even when the mold wall is allowed to wear to the maximum. In the case of a mold that has not yet been used, the distance between the shaft surface and sensors is given and known through the installation. This distance is denoted by L; it corresponds to zero mold wear, i.e. not worn out. During casting, each distance measuring sensor determines the current distance A of the strand surface from the sensor and leads this to the elimination of the influence (temporary) lifting of the strand from the shaft walls of a minimum value memory assigned to it, which is the smallest in the measured value supplied while deleting the last stored value saves. The current value of the wear of the shaft wall results from the stored distance value A 'to A L = L - A'. From the AL values of the sensors used it follows when the mold has to be replaced and, if necessary, the casting has to be stopped.

Die Sensoren können auch so ausgeführt werden, daß sie nur Abstandswerte im Bereich der kritischen Abnutzung ausreichend genau messen, vgl. dazu Fig. 2. Das ermöglicht bei Wirbelstrom-Meßsensoren eine kleinere und einfachere Bauform 5. Zudem muß die Meßsensoröffnung 6 nur so tief sein, daß sich erst bei kritischen Werten der Abnutzung kein Wandmaterial (üblicherweise Kupfer) mehr zwischen Meßsensor 5 und Strangoberfläche befindet. Damit der Strang nicht durch die für den Sensor notwendige Öffnung 4 in der Kokillenwand mechanisch belastet wird, wird der Raum zwischen Sensorfläche und Kokillenwand mit einem unmagnetischen, elektrisch nicht leitenden Material 7 ausgefüllt, welches ähnliche mechanische Abriebeigenschaften wie die Kokillenwand hat.The sensors can also be designed so that they only measure distance values in the area of critical wear with sufficient accuracy, cf. See Fig. 2. This enables a smaller and simpler design 5 in eddy current measuring sensors. In addition, the measuring sensor opening 6 only has to be so deep that there is no more wall material (usually copper) between the measuring sensor 5 and the surface of the strand only when the wear values are critical. So that the strand is not mechanically stressed by the opening 4 required for the sensor in the mold wall, the space between the sensor surface and the mold wall is filled with a non-magnetic, electrically non-conductive material 7, which has similar mechanical abrasion properties as the mold wall.

Eine wesentliche Verbesserung des Gießprozesses wird durch Nachführen der Schachtwände auf die Sollgeometrie des Schachtes erreicht, in dem die gemessenen Abnutzungswerte einer Verstelleinrichtung zugeführt werden, die die Kokillenwände entsprechend diesen Werten verschiebt. Mit Hilfe geeignet angeordneter Meßsensoren 3 und 3' in Fig. 1 kann so insbesondere bei Brammen-Stranggießanlagen die für den Prozeßverlauf besonders wichtige Konizität der Schmalflächen des Kokillenschachtes auf dem geforderten Wert gehalten werden. Die Vorrichtung zur Ermittlung der Kokillenwandabnutzung gemäß der Erfindung wird dazu verwendet, die Abhebung der Strangschale von der Kokilleninnenwand zu ermitteln. Dies geschieht dadurch,daß aus der Differenz zwischen dem aktuell gemessenen Abstand A zwischen Meßsensor und Strangoberfläche und dem gespeicherten kleinsten Abstandswert A' die Abhebung Δ A = A - A' der Strangoberfläche von der Kokilleninnenwand ermittelt wird. Aus den gemessenen Abhebewerten wird eine Kenngröße ermittelt, die einer oder der oben genannten Konizitäts-Verstelleinrichtung zur entsprechenden Verstellung der Kokillenwand zugeleitet wird. Diese Kenngröße wird durch Maximalwertspeicherung der Abhebewerte gewonnen.A significant improvement in the casting process is achieved by tracking the shaft walls to the nominal geometry of the shaft, in which the measured wear values are fed to an adjusting device which shifts the mold walls in accordance with these values. With the aid of suitably arranged measuring sensors 3 and 3 'in FIG. 1, the conicity of the narrow surfaces of the mold shaft, which is particularly important for the process, can be kept at the required value, particularly in the case of continuous slab casting plants. The device for determining the mold wall wear according to the invention is used to determine the lifting of the strand shell from the mold inner wall. This is done in that the difference Δ A = A - A 'of the strand surface from the mold inner wall is determined from the difference between the currently measured distance A between the measuring sensor and the strand surface and the stored smallest distance value A'. A characteristic variable is determined from the measured lift-off values, which is fed to one or the conicity adjustment device mentioned above for the corresponding adjustment of the mold wall. This parameter is obtained by storing the maximum value of the lift-off values.

Mit einem Meßsensor 3'' kurz unterhalb der Kokille wird die Verformung der Strangschale nach Austritt aus der Kokille beobachtet. Sie hängt vorwiegend von der Strangabzugsgeschwindigkeit und dem Kontakt zwischen Strang und Kokilleninnenwänden und damit von der Konizität ab.With a measuring sensor 3 '' just below the mold, the deformation of the strand shell after it emerges from the mold is observed. It mainly depends on the strand withdrawal speed and the contact between the strand and the mold inner walls and thus on the taper.

Da mit der Verformung die Gefahr des Entstehens von Materialfehlern in der Strangschale oder gar des Aufreißens wächst, soll bei zu großer Verformung die Konizität und gegebenenfalls auch die Strangabzugsgeschwindigkeit verringert werden. Einige Anlagenzustände - wie zum Beispiel Gießbeginn und sehr langsamer Strangvorschub - erfordern eine andere Reaktion der Verstelleinrichtung als ein annähernd stationärer Betrieb. Daher werden die Sollgrößen für die Kokillenwandverstellung unter Berücksichtigung der in dieser Hinsicht relevanten Anlagenparameter (Stranglänge, Abzugsgeschwindigkeit) mit Hilfe eines Rechners aus den Meßwerten der Vorrichtung bestimmt.Since with the deformation there is a risk of Ma material defects in the strand shell or even tearing open, the conicity and possibly also the strand withdrawal speed should be reduced if the deformation is too great. Some system states - such as the start of casting and very slow strand feed - require a different reaction from the adjustment device than an almost stationary operation. Therefore, the target values for the mold wall adjustment are determined with the aid of a computer from the measured values of the device, taking into account the relevant plant parameters (strand length, take-off speed).

Bei dem in Figur 3 gezeigten Ausführungsbeispiel mit Schallsensoren werden die Meßköpfe 8 direkt an die Kokillenwand 1 angekoppelt. Gearbeitet wird nach dem Puls-Echo-Verfahren. Die Abnutzung der Kokillenwand ergibt sich aus der Laufzeit des an der Schachtoberfläche reflektierten Schallimpulses. Die Reflektion wird durch die Strangoberfläche und die "Schmiermittelschicht" 9 zwischen Strang- und Schachtoberfläche beeinflußt ung kann zeitweise sehr klein werden. Daher wird hier - analog zum vorigen Ausführungsbeispiel - eine Minimalwertspeicherung durchgeführt. Eine Bestimmung der Strangabhebung ist mit Schall dann möglich, wenn der Raum zwischen Strangoberfläche und Schacht vollständig mit Gießpulver ausgefüllt ist.In the exemplary embodiment shown in FIG. 3 with sound sensors, the measuring heads 8 are coupled directly to the mold wall 1. The pulse-echo method is used. The wear of the mold wall results from the transit time of the sound pulse reflected on the shaft surface. The reflection is influenced by the strand surface and the "lubricant layer" 9 between the strand and shaft surface and can at times become very small. A minimum value storage is therefore carried out here - analogous to the previous exemplary embodiment. A determination of the strand lift-off is possible with sound if the space between the strand surface and the shaft is completely filled with casting powder.

Claims (9)

1. Vorrichtung zur Ermittlung der Kokillenwandabnutzung während des Gießprozesses,
dadurch qekennzeichnet, daß in den Kokillenwänden (1) ein oder mehrere Abstandsmeßsensoren (3,3',8) so eingebaut werden, daß sie von dem sich abhebenden und bewegenden Strang auch dann nicht berührt werden, wenn die Kokillenwand sich im Betrieb abgenutzt hat, daß das sich ergebende kleinste Abstandssignal für den Abstand zwischen einem Abstandsmeßsensor (3,3',8) und dem Strang (2) bzw. Oberfläche der Kokilleninnenwand (1), einem Minimalwertspeicher unter Löschung des zuletzt gespeicherten Wertes zugeführt und die Differenz aus dem Anfangswert des Abstandes Meßsensor - Kokilleninnenwand L und dem jeweils gespeicherten kleinsten Abstandswert Meßsensor - Strangoberfläche bzw. Meßsensor - Wandoberfläche A' gebildet wird.
1. Device for determining mold wall wear during the casting process,
characterized in that one or more distance measuring sensors (3, 3 ', 8) are installed in the mold walls (1) in such a way that they are not touched by the lifting and moving strand even if the mold wall has worn out during operation, that the resulting smallest distance signal for the distance between a distance measuring sensor (3,3 ', 8) and the strand (2) or surface of the mold inner wall (1), a minimum value memory with deletion of the last stored value and the difference from the initial value of the distance between the measuring sensor and the mold inner wall L and the respectively stored smallest distance value between the measuring sensor and the strand surface b between the measuring sensor and the wall surface A '.
2. Verwendung der Vorrichtung nach Anspruch 1 zur Ermittlung der Abhebung der Strangschale von der Kokilleninnenwand,
dadurch qekennzeichnet, daß aus der Differenz zwischen dem aktuell gemessenen Abstand A zwischen Meßsensor und Strangoberfläche und dem gespeicherten kleinsten Abstandswert A' die Abhebung ΔA = A - A' der Strangoberfläche von der Kokilleninnenwand ermittelt wird.
2. Use of the device according to claim 1 for determining the lifting of the strand shell from the mold inner wall,
characterized in that the difference between the lift ΔA = A - A 'of the strand surface from the mold inner wall is determined from the currently measured distance A between the measuring sensor and the strand surface and the stored smallest distance value A'.
3. Vorrichtung nach Anspruch 1 oder 1 und 2, dadurch qekennzeichnet, daß der Meßsensor ein Wirbelstromsensor ist.3. Device according to claim 1 or 1 and 2, characterized in that the measuring sensor is an eddy current sensor. 4. Vorrichtung nach Anspruch 3, dadurch qekennzeichnet, daß die Kokillenwand (1) eine den Sensor (3,5) beinhaltende Öffnung (4,6) besitzt, die so ausgestaltet ist, daß sich zwischen der Stirnseite des Sensors und der Strangoberfläche (2) nur hochfrequenzmäßig durchlässiges Material befindet.4. The device according to claim 3, characterized in that the mold wall (1) has an opening (4, 6) containing the sensor (3, 5), which is designed such that there is between the end face of the sensor and the strand surface (2 ) only material that is permeable to high frequencies. 5. Vorrichtung nach Anspruch 4, dadurch qekennzeichnet, daß die Öffnung (4) in der Kokillenwand mit einem Material (7), welches unmagnetisch, elektrisch nicht leitend und ähnliche Abriebeigenschaften wie die Kokillenwand hat, so verschlossen ist, daß die Kokilleninnenwände jeweils eine ebene Fläche bilden.5. The device according to claim 4, characterized in that the opening (4) in the mold wall with a material (7) which is non-magnetic, electrically non-conductive and has similar abrasion properties as the mold wall, is closed so that the mold inner walls are each level Form area. 6. Vorrichtung nach Anspruch 1 oder 1 und 2, dadurch qekennzeichnet, daß der Meßsensor ein Ultraschallsensor ist.6. The device according to claim 1 or 1 and 2, characterized in that the measuring sensor is an ultrasonic sensor. 7. Vorrichtung nach Anspruch 1, dadurch qekennzeichnet, daß bei verstellbaren Kokillen die ermittelte Abnutzung einer Kokillenwand einer Verstelleinrichtung zugeführt wird, die die Kokillenwand entsprechend der Abnutzung verschiebt.7. The device according to claim 1, characterized in that, in the case of adjustable molds, the determined wear of a mold wall is fed to an adjusting device which moves the mold wall in accordance with the wear. 8. Vorrichtung nach Anspruch 2 oder 2 und 7, dadurch qekennzeichnet, daß aus den gemessenen Abhebewerten eine Kenngröße ermittelt wird, die einer oder der Konizitäts-Verstelleinrichtung zur entsprechenden Verstellung der Kokillenwand zugeleitet wird.8. The device according to claim 2 or 2 and 7, characterized in that a parameter is determined from the measured lift-off values, which one or the conicity adjusting device for the corresponding Adjustment of the mold wall is fed. 9. Vorrichtung nach Anspruch 8, dadurch qekennzeichnet, daß diese Kenngröße durch Maximalwertspeicherung der Abhebewerte gewonnen wird.9. The device according to claim 8, characterized in that this parameter is obtained by storing the maximum value of the lift-off values.
EP84102183A 1983-03-16 1984-03-01 Method for detecting the wear of the wall of a mould during continuous casting and for detecting the removal of the strand shell from the internal wall of the mould Expired EP0120338B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT84102183T ATE25016T1 (en) 1983-03-16 1984-03-01 PROCEDURE FOR DETERMINING MOLD WEAR WEAR DURING THE CASTING PROCESS AND DETERMINING THE LIFTING OF THE STRIP SHELL FROM THE INNER WALL OF THE MOLD.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE3309885 1983-03-16
DE19833309885 DE3309885A1 (en) 1983-03-16 1983-03-16 DEVICE FOR DETECTING THE CHILLER WALL WEAR DURING THE MOLDING PROCESS AND USING THE SAME FOR DETERMINING THE LIFTING OF THE STRAND SHELL FROM THE CHILLER INNER WALL

Publications (2)

Publication Number Publication Date
EP0120338A1 true EP0120338A1 (en) 1984-10-03
EP0120338B1 EP0120338B1 (en) 1987-01-21

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Application Number Title Priority Date Filing Date
EP84102183A Expired EP0120338B1 (en) 1983-03-16 1984-03-01 Method for detecting the wear of the wall of a mould during continuous casting and for detecting the removal of the strand shell from the internal wall of the mould

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Country Link
US (1) US4545420A (en)
EP (1) EP0120338B1 (en)
JP (1) JPS59169658A (en)
AT (1) ATE25016T1 (en)
DE (1) DE3309885A1 (en)

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EP3135402A1 (en) * 2015-08-27 2017-03-01 Primetals Technologies Austria GmbH Mould and method for monitoring a mould
EP3385007A1 (en) * 2017-04-06 2018-10-10 SMS Group GmbH Device with wear part and measuring device for wear

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US5477618A (en) * 1994-05-03 1995-12-26 Gibson; Stephen P. Sand core dimension checking apparatus
DE102007039882A1 (en) * 2007-04-26 2008-11-06 Sms Demag Ag continuous casting
DE102008011277A1 (en) * 2008-02-27 2009-09-10 Siemens Aktiengesellschaft Mold for casting liquid metal, comprises volumes limited by a mold boundary for receiving a liquid metal, and a device intended for detecting liquid metal in a detection zone using ultrasonic waves and having a transmitter and a receiver

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EP3135402A1 (en) * 2015-08-27 2017-03-01 Primetals Technologies Austria GmbH Mould and method for monitoring a mould
EP3385007A1 (en) * 2017-04-06 2018-10-10 SMS Group GmbH Device with wear part and measuring device for wear
EP3492188A1 (en) * 2017-04-06 2019-06-05 SMS Group GmbH Device with wear part and measuring device for wear

Also Published As

Publication number Publication date
DE3309885C2 (en) 1987-06-25
US4545420A (en) 1985-10-08
EP0120338B1 (en) 1987-01-21
DE3309885A1 (en) 1984-09-20
JPS59169658A (en) 1984-09-25
ATE25016T1 (en) 1987-02-15

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