EP0029796A1 - System for measuring the height of the slag in a metallurgical vessel, and for determining its physical condition - Google Patents

System for measuring the height of the slag in a metallurgical vessel, and for determining its physical condition Download PDF

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Publication number
EP0029796A1
EP0029796A1 EP80630037A EP80630037A EP0029796A1 EP 0029796 A1 EP0029796 A1 EP 0029796A1 EP 80630037 A EP80630037 A EP 80630037A EP 80630037 A EP80630037 A EP 80630037A EP 0029796 A1 EP0029796 A1 EP 0029796A1
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EP
European Patent Office
Prior art keywords
measuring system
enclosure
microphone
cell
crucible
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Granted
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EP80630037A
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German (de)
French (fr)
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EP0029796B1 (en
Inventor
Jean Baumert
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Arcelor Luxembourg SA
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Arbed SA
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    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21C—PROCESSING OF PIG-IRON, e.g. REFINING, MANUFACTURE OF WROUGHT-IRON OR STEEL; TREATMENT IN MOLTEN STATE OF FERROUS ALLOYS
    • C21C5/00—Manufacture of carbon-steel, e.g. plain mild steel, medium carbon steel or cast steel or stainless steel
    • C21C5/28—Manufacture of steel in the converter
    • C21C5/30—Regulating or controlling the blowing

Definitions

  • the present invention relates to a system for determining the level and for assessing the physical state of the slag in a metallurgical vessel, in particular in a steelworks to oxygen converter.
  • Knowledge of the level of slag in a steelworks converter is important, both from the metallurgical point of view, as a parameter of the degree of refining progress, and from the point of view of safety, in order to prevent overflow .
  • the applicant has developed a system for measuring the level of the slag which allows at the same time an evaluation of the consistency thereof, which constitutes important information, especially for the refining of phosphorous cast irons where a slag of a frothy consistency was considered desirable.
  • This measurement system that the applicant described in the Luxembourg patent no. 71.261, includes a thermostatic acoustic conduit which is placed above the converter and which picks up the noise emitted by the oxygen blowing lance. After filtering the frequencies whose origin is foreign to the parameters of interest for the measurement proper, we retain a signal whose interpretation allows us to conclude on the degree of the noise absorbed by the slag and thereby on the degree of the sparkling character present, as well as at its level in the crucible.
  • the object of the invention therefore consists in proposing a measurement system making it possible to continue using the principle of measuring the sound of the blowing lance in order to establish the thickness of the slag layer and its consistency, both in in the case of several neighboring crucibles, only in the case of installations where the refining is carried out in a vacuum.
  • the measurement system according to the invention which is characterized in that a sufficient number of pipes of the cooling system installed in the chimney above the crucible have an extension and form a cylindrical crown which projects outwards from the chimney shell and whose axis is inclined towards the center of the crucible, which crown forms the seat of a cylindrical crimp connected to a circular double-walled cell cooled with water and provided with a central orifice, to which cell is connected the enclosure which contains the actual acoustic sensor.
  • This acoustic sensor is preferably a microphone known per se, as it is used for example in the measurement system described by the applicant in the text of the Luxembourg patent no. 71.261. It is the same for the electronic assembly which is connected to said acoustic sensor and which ensures the processing of the signals received, as well as their conversion into significant information, either for the operator or for the automatic processor which conducts the process of the refining.
  • the idea which is the basis of the invention consists in designing an acoustic capture installation adapted to the environmental conditions existing inside the crucible-chimney assembly itself and in housing this installation in a place where a maximum protection can be accommodated for the sensor itself which is an extremely sensitive instrument.
  • the challenge is to stay that this instrument inside the fireplace in the crucible rife tempera- t ure s above 1000 0 to ensure good management of significant frequency sounds, even if a facility where refining is carried out in a vacuum, is not possible without the arrangement according to the invention of the chimney cooling pipes to form the seat of the enclosure which contains the acoustic sensor.
  • the enclosure containing the acoustic sensor is connected to the circular cell.
  • a sound recording element in the form of a disc the central part of which is flared, is interposed between the enclosure and the circular cell.
  • This flared blunt part is located inside the central orifice of the circular cell and it is directed towards the source of the noise, i.e. towards the crucible.
  • the disc bears on the one hand against the circular cell and on the other hand by means of a flexible seal, against the enclosure which contains the acoustic sensor.
  • a first embodiment of the measurement system according to the invention consists in providing between the microphone and the sound pickup element an acoustic tube which is housed in one enclosure.
  • the advantage of this embodiment lies in the fact that the microphone is thus well protected from any risk of damage, the acoustic tube being able to be produced in lengths greater than 3 meters. However, this implies the use of a linearization filter making it possible to compensate for the proper resonances of the acoustic tube.
  • a second embodiment provides for housing the microphone directly in the enclosure, opposite the sound pickup element.
  • the microphone is housed in a tube which carries at its end opposite the sound pick-up element a perforated plug preferably made of steel.
  • a brass membrane with a thickness of ⁇ 0.1 mm which may include a layer of quartz (deposited by vaporization).
  • the role of the perforated capsule is to protect the membrane against the heat of irradiaticnet against possible projections, while the membrane itself protects the microphone from dust
  • the distances between the perforated capsule and the membrane, resp. between the diaphragm and the microphone, are defined and reproducible, so that a calibration of the sound recording part is only necessary once.
  • the enclosure which contains the sensor is cooled using a neutral gas, preferably nitrogen, which is introduced behind the enclosure and which exits through the flared part of the sound pickup element.
  • a neutral gas preferably nitrogen
  • the gas makes it possible, by exiting through the flared part of the sound pick-up element, to spread the flames and dust from this orifice.
  • the enclosure usefully includes a double wall cooled with water.
  • This water must also be cold water, with a temperature around 10 ° C, while the water which circulates in the pipes which form the cylindrical ring supporting the measuring device, shows temperatures higher than 50 ° C.
  • the circular cell also has a double wall inside which circulates cooling water.
  • the crimping surrounding the cylindrical crown of pipes can be cooled if necessary, preferably with nitrogen.
  • FIG. 1 shows a diagram of the arrangement according to the invention of the cooling pipes in a cylindrical ring to form the seat of the measuring device
  • fig. 2 shows a section of the embodiment of the installation comprising an acoustic tube intermediate between the microphone and the sound pick-up element
  • FIG. 3 shows the embodiment which provides for housing the microphone directly in front of the sound pickup element.
  • the diagram in fig. 1 shows the advantage achieved by the arrangement according to the invention of the seat for the measuring device.
  • the latter is sheltered from major sources of damage while retaining access to the sources of the noise to be picked up.
  • the fact of embedding the measuring device in the cooling pipe of the chimney in the manner described also makes it possible to circumvent the difficulties which could arise during cleaning operations in the event that the system is housed independently in the chimney. , eg by suspension. Indeed the system would constitute in this case an obstacle and would not fail to be damaged during the cleaning operations which necessarily take place in harsh conditions.
  • the circular cell (20) which has a water cooling circuit with the inlet mouths, resp. outlet (21) resp. (22).
  • the cell (20) has a central orifice (23) with a diameter of about 100 mm.
  • a flexible seal (24) Between the cell (20) and the crimp (11) is a flexible seal (24).
  • the cell (20) is in turn connected to the enclosure (40) which contains the acoustic sensor. Between the cell (20) and the enclosure (40) is the sound pickup element (30) which is a disc, the central part of which forms a blunt flare (31). The disc (30) touches the cylindrical cell (20) opposite each other, which has the effect of cooling the disc (30). Its other side touches a flexible seal (25) interposed between the disc (30) and the cell (20).
  • the cell (20), disc (30), seal 125) and enclosure (40) assembly is connected using the bolts (26).
  • the enclosure (40) comprises the acoustic tube (50) which is housed in the tube (51) through which a stream of nitrogen (N2) passes, which escapes through the orifice of the flared part (31) of the sound recording element.
  • the tube (50) which may have a length greater than 3 m, leads to the microphone, not shown.
  • fig. 3 shows essentially the same cell assembly (20), disc (30), seal (25), enclosure (40) as in fig. 2.
  • toroidal rings (70) ensure that the respective distances between the perforated capsule (55) and the membrane (56) and between the membrane (56) and the microphone (60) are constant and reproducible.
  • the microphone (60) is held in place by means of a spring (57).
  • the terminal part of the enclosure (40) is closed by means of a plastic padding.
  • flexible insulations (24) in FIG. 2 and (25) in fig. 2 and in fig. 3 to largely eliminate mechanical vibrations and shocks.
  • the electronic part of the measurement system according to the invention comprises several filters which eliminate noise of undesirable frequencies in the present context and which leave only the sounds which are taken into account for the measurements to be taken. carry out.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Manufacturing & Machinery (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Investigating Or Analyzing Materials By The Use Of Ultrasonic Waves (AREA)
  • Analysing Materials By The Use Of Radiation (AREA)
  • Investigating And Analyzing Materials By Characteristic Methods (AREA)
  • Waste-Gas Treatment And Other Accessory Devices For Furnaces (AREA)
  • Length Measuring Devices With Unspecified Measuring Means (AREA)
  • Length Measuring Devices By Optical Means (AREA)
  • Length-Measuring Instruments Using Mechanical Means (AREA)
  • Curing Cements, Concrete, And Artificial Stone (AREA)
  • Furnace Charging Or Discharging (AREA)

Abstract

A steel refining system has a crucible having an upwardly open mouth and containing a steel melt covered by slag, an oxygen lance directed downwardly into the mouth at the melt, a hood fitting downwardly over the mouth and having a hood wall formed by a multiplicity of coolant tubes, and an arrangement for circulating a coolant through these tubes. The tubes form a tubular hood-wall extension that has an outer end and is centered on an axis trained on the melt on the crucible. A holder is mounted on the outer end of this extension and contains a sound transducer carried by the holder and directed along the axis at the melt. A circuit is connected to this transducer for determining slag thickness by means of the sound detected by the transducer. The holder itself comprises a circularly annular hollow cell fixed by means of a collar to the extension and a transducer housing that is fixed to this cell and therethrough to the extension. The cell defines a passage aligned with the axis and is connected to a separate coolant circuit to prevent overheating of the transducer.

Description

La présente invention concerne un système pour la détermination du niveau et pour l'appréciation de l'état physique de la scorie dans un récipient métallurgique, notamment dans un convertisseur d'aciérie à l'oxygène.The present invention relates to a system for determining the level and for assessing the physical state of the slag in a metallurgical vessel, in particular in a steelworks to oxygen converter.

La connaissance du niveau de la scorie dans un convertisseur d'aciérie est importante, tant du point de vue métallurgique, comme paramètre du degré d'avancement de l'affinage, que du point de vue de la sécurité, en vue de prévenir un débordement.Knowledge of the level of slag in a steelworks converter is important, both from the metallurgical point of view, as a parameter of the degree of refining progress, and from the point of view of safety, in order to prevent overflow .

Ainsi le déposant a développé un système de mesure du niveau de la scorie qui permet en même temps une évaluation de la consistance de celle-ci, ce qui constitue une information importante, surtout pour l'affinage de fontes phosphoreuses où une scorie d'une consistance mousseuse était jugée désirable.Thus the applicant has developed a system for measuring the level of the slag which allows at the same time an evaluation of the consistency thereof, which constitutes important information, especially for the refining of phosphorous cast irons where a slag of a frothy consistency was considered desirable.

Ce système de mesure que le déposant a décrit dans le brevet luxembourgeois no. 71.261, comporte un conduit acoustique ther- mostatisé qui est disposé au-dessus du convertisseur et qui capte le bruit émis par la lance de soufflage d'oxygène. Après filtrage des fréquences dont l'origine est étrangère aux paramètres qui intéressent pour la mesure proprement dite, on retient un signal dont l'interprétation permet de conclure au degré du bruit absorbé par la scorie et par là au degré du caractère mousseux présent, ainsi qu'à son niveau dans le creuset.This measurement system that the applicant described in the Luxembourg patent no. 71.261, includes a thermostatic acoustic conduit which is placed above the converter and which picks up the noise emitted by the oxygen blowing lance. After filtering the frequencies whose origin is foreign to the parameters of interest for the measurement proper, we retain a signal whose interpretation allows us to conclude on the degree of the noise absorbed by the slag and thereby on the degree of the sparkling character present, as well as at its level in the crucible.

Etant donné d'une part l'emplacement du capteur acoustique qui est situé essentiellement en-dehors du creuset pour réduire le plus possible les risques d'endommagement par projections et éclaboussures, et d'autre part le fait que l' installation de mesure capte les bruits à fréquences caractéristiques issus de la lance de soufflage, il est clair que ladite installation n'est utilisable que sous condition que dans l'aciérie un seul creuset à la fois se trouve en état de soufflage. En effet dans le cas de 2 ou plusieurs convertisseurs en phase de soufflage, l'installation ne manquerait d'être perturbée par la captation des bruits caractéristiques émis par le convertisseur voisin.Given on the one hand the location of the acoustic sensor which is situated essentially outside the crucible to reduce as much as possible the risks of damage by projections and splashes, and on the other hand the fact that the measuring installation picks up noises at characteristic frequencies from the blowing lance, it is clear that said installation can only be used on condition that in the steelworks only one crucible at a time is in the blowing state. Indeed, in the case of 2 or more converters in the blowing phase, the installation would not fail to be disturbed by the capture of the characteristic noises emitted by the neighboring converter.

Le même système de mesure où l'emplacement du capteur est situé en-dehors du creuset, est pratiquement inutilisable dans les installations d'affinage où le creuset peut être relié de manière plus ou moins étanche à la cheminée p.ex. à l'aide d'une jupe mobile munie de vérins hydrauliques. Il s'agit dans ce cas d'installations d'affinage où au cours du soufflage on empêche dans la mesure du possible l'accès d'air dans la cheminée, soit pour soustraire les gaz formés au cours de l'élaboration en vue d'une utilisation comme gaz de combustion, soit pour prévenir une post-combustion du monoxyde de carbone au voisinage immédiat de la tuyauterie du système de refroidissement installé dans la cheminée.The same measurement system where the location of the sensor is located outside the crucible is practically unusable in refining installations where the crucible can be more or less tightly connected to the chimney, eg to the using a movable skirt fitted with hydraulic cylinders. In this case, these are refining installations where, during blowing, air is prevented from entering the chimney as far as possible, that is to remove the gases formed during the preparation for '' use as a combustion gas, either to prevent post-combustion of carbon monoxide in the immediate vicinity of the cooling system piping installed in the chimney.

Le but de l'invention consiste donc à proposer un système de mesure permettant de continuer à utiliser le principe de la mesure du son de la lance de soufflage en vue d'établir l' épaisseur de la couche de scorie et sa consistance, tant dans le cas de plusieurs creusets voisins, que dans le cas d'installations où l'affinage est opéré en vase clos.The object of the invention therefore consists in proposing a measurement system making it possible to continue using the principle of measuring the sound of the blowing lance in order to establish the thickness of the slag layer and its consistency, both in in the case of several neighboring crucibles, only in the case of installations where the refining is carried out in a vacuum.

Ce but est atteint par le système de mesure suivant l'invention qui est caractérisé en ce qu'un nombre suffisant de tuyaux du système de refroidissement installé dans la cheminée au-dessus du creuset comportent une rallonge et forment une couronne cylindrique qui saillit vers l'extérieur de l'enveloppe de la cheminée et dont l'axe est incliné vers le centre du creuset, laquelle couronne forme l'assise d'un sertissage cylindrique relié à une cellule circulaire à double paroi refroidie à l'eau et munie d'un orifice central, à laquelle cellule est reliée l'enceinte qui contient le capteur acoustique proprement dit.This object is achieved by the measurement system according to the invention which is characterized in that a sufficient number of pipes of the cooling system installed in the chimney above the crucible have an extension and form a cylindrical crown which projects outwards from the chimney shell and whose axis is inclined towards the center of the crucible, which crown forms the seat of a cylindrical crimp connected to a circular double-walled cell cooled with water and provided with a central orifice, to which cell is connected the enclosure which contains the actual acoustic sensor.

Ce capteur acoustique est de préférence un microphone connu en soi, tel qu'il est utilisé p.ex. dans le système de mesure décrit par le déposant dans le texte du brevet luxembourgeois no. 71.261. Il en est de même pour l'ensemble électronique qui est relié audit capteur acoustique et qui assure le traitement des signaux captés, ainsi que leur conversion en informations significatives, soit pour l'opérateur, soit pour le processeur automatique qui conduit le processus de l'affinage.This acoustic sensor is preferably a microphone known per se, as it is used for example in the measurement system described by the applicant in the text of the Luxembourg patent no. 71.261. It is the same for the electronic assembly which is connected to said acoustic sensor and which ensures the processing of the signals received, as well as their conversion into significant information, either for the operator or for the automatic processor which conducts the process of the refining.

L'idée qui est à la base de l'invention consiste à concevoir une installation de captation acoustique adaptée aux conditions d'environnement existant à l'intérieur même de l'ensemble creuset-cheminée et de loger cette installation à un endroit où un maximum de protection peut être accommodé pour le capteur proprement dit qui est un instrument extrêmement sensible. La gageure qui consiste à loger cet instrument à l'intérieur de la cheminée du creuset où règnent des tempéra- tures supérieures à 10000 pour garantir une prise valable des sons de fréquence significative, même en cas d'une installation où l'affinage est opéré en vase clos, n'est possible sans l'aménagement suivant l'invention des tuyaux de refroidissement de la cheminée pour former l'assise de l'enceinte qui contient le capteur acoustique.The idea which is the basis of the invention consists in designing an acoustic capture installation adapted to the environmental conditions existing inside the crucible-chimney assembly itself and in housing this installation in a place where a maximum protection can be accommodated for the sensor itself which is an extremely sensitive instrument. The challenge is to stay that this instrument inside the fireplace in the crucible rife tempera- t ure s above 1000 0 to ensure good management of significant frequency sounds, even if a facility where refining is carried out in a vacuum, is not possible without the arrangement according to the invention of the chimney cooling pipes to form the seat of the enclosure which contains the acoustic sensor.

L'enceinte qui contient le capteur acoustique est reliée à la cellule circulaire. Suivant l'invention un élément de prise du son en forme d'un disque, dont la partie centrale est évasée, est intercalé entre l'enceinte et la cellule circulaire. Cette partie évasée en tromblon se trouve à l'intérieur de l' orifice central de la cellule circulaire et elle est dirigée vers la source du bruit, c.à.d. vers le creuset.The enclosure containing the acoustic sensor is connected to the circular cell. According to the invention a sound recording element in the form of a disc, the central part of which is flared, is interposed between the enclosure and the circular cell. This flared blunt part is located inside the central orifice of the circular cell and it is directed towards the source of the noise, i.e. towards the crucible.

Le disque s'appuie d'une part contre la cellule circulaire et d'autre part par l'intermédiaire d'un joint souple, contre l' enceinte qui contient le capteur acoustique.The disc bears on the one hand against the circular cell and on the other hand by means of a flexible seal, against the enclosure which contains the acoustic sensor.

Une première forme d'exécution du système de mesure suivant l'invention consiste à prévoir entre le microphone et l'élément de prise du son un tube acoustique qui est logé dans 1' enceinte. L'avantage de cette forme d'exécution réside dans le fait que le microphone se trouve ainsi bien à l'abri de tout risque d'endommagement, le tube acoustique pouvant être réalisé en longueurs supérieures à 3 mètres. Or, ceci implique l'utilisation d'un filtre de linéarisation permettant de compenser les résonnances propres du tube acoustique.A first embodiment of the measurement system according to the invention consists in providing between the microphone and the sound pickup element an acoustic tube which is housed in one enclosure. The advantage of this embodiment lies in the fact that the microphone is thus well protected from any risk of damage, the acoustic tube being able to be produced in lengths greater than 3 meters. However, this implies the use of a linearization filter making it possible to compensate for the proper resonances of the acoustic tube.

Une deuxième forme d'exécution prévoit de loger le microphone directement dans l'enceinte, en face de l'élément de prise du son. Dans ce cas le microphone est logé dans un tube qui porte à son extrémité en face de l'élément de prise du son un bouchon perforé de préférence en acier. Entre cette capsule perforée et le microphone se trouve une membrane en laiton d'une épaisseur de µ 0,1 mm qui peut comporter une couche de quartz (déposée par vaporisation).A second embodiment provides for housing the microphone directly in the enclosure, opposite the sound pickup element. In this case the microphone is housed in a tube which carries at its end opposite the sound pick-up element a perforated plug preferably made of steel. Between this perforated capsule and the microphone is a brass membrane with a thickness of µ 0.1 mm which may include a layer of quartz (deposited by vaporization).

Le rôle de la capsule perforée consiste à protéger la membrane contre la chaleur d'irradiaticnet contre d'éventuelles projections, tandis que la membrane elle-même met le microphone à l'abri des poussièresThe role of the perforated capsule is to protect the membrane against the heat of irradiaticnet against possible projections, while the membrane itself protects the microphone from dust

Les distances entre la capsule perforée et la membrane, resp. entre la membrane et le microphone, sont définies et reproductibles, de manière à ce qu'un étalonnage de la partie prise de son ne soit nécessaire qu'une seule fois.The distances between the perforated capsule and the membrane, resp. between the diaphragm and the microphone, are defined and reproducible, so that a calibration of the sound recording part is only necessary once.

Soit qu'on choisit la première ou la deuxième forme d'exécution du système de mesure suivant l'invention, l'enceinte qui contient le capteur est refroidie à l'aide d'un gaz neutre, de préférence de l'azote, qui est introduit en arrière de l' enceinte et qui sort par la partie évasée de l'élément de prise du son.Either the first or the second embodiment of the measurement system according to the invention is chosen, the enclosure which contains the sensor is cooled using a neutral gas, preferably nitrogen, which is introduced behind the enclosure and which exits through the flared part of the sound pickup element.

L'évasement en tromblon de ce dernier, dont la forme rappelle un conduit Venturi, évite des variations brusques de la vitesse d'écoulement et de changements de direction du gaz qui engendrent des bruits parasites.The flaring out of the latter, whose shape is reminiscent of a Venturi duct, avoids sudden variations in the flow speed and changes in direction of the gas which generate parasitic noises.

En plus du refroidissement de l'enceinte et du capteur, le gaz permet en sortant par la partie évasée de l'élément de prise du son, d'écarter les flammes et les poussières de cet orifice.In addition to cooling the enclosure and the sensor, the gas makes it possible, by exiting through the flared part of the sound pick-up element, to spread the flames and dust from this orifice.

En cas de la forme d'exécution qui prévoit de loger le microphone directement en face de l'élément de prise du son, l' enceinte comporte utilement une double paroi refroidie à l' eau. Cette eau doit par ailleurs être de l'eau froide, d'une température aux environs de 10°C, tandis que l'eau qui circule dans les tuyaux qui forment la couronne cylindrique supportant le dispositif de mesure, accuse des températures supérieures à 50°C.In the case of the embodiment which provides for housing the microphone directly opposite the sound pickup element, the enclosure usefully includes a double wall cooled with water. This water must also be cold water, with a temperature around 10 ° C, while the water which circulates in the pipes which form the cylindrical ring supporting the measuring device, shows temperatures higher than 50 ° C.

La cellule circulaire comporte également une double paroi à l'intérieur de laquelle circule de l'eau de réfrigération. Le sertissage entourant la couronne cylindrique de tuyaux peut en cas de besoin être refroidi, de préférence par de l'azote.The circular cell also has a double wall inside which circulates cooling water. The crimping surrounding the cylindrical crown of pipes can be cooled if necessary, preferably with nitrogen.

D'autres caractéristiques ressortent de la description des dessins où la fig. 1 représente un schéma de l'aménagement suivant l'invention des tuyaux de refroidissement en couronne cylindrique pour former l'assise du dispositif de mesure; la fig. 2 montre une coupe de la forme d'exécution de l'installation comportant un tube acoustique intermédiaire entre le microphone et l'élément de prise du son, tandis que la fig. 3 représente la forme d'exécution qui prévoit de loger le microphone directement en face de l'élément de prise du son.Other characteristics appear from the description of the drawings in which FIG. 1 shows a diagram of the arrangement according to the invention of the cooling pipes in a cylindrical ring to form the seat of the measuring device; fig. 2 shows a section of the embodiment of the installation comprising an acoustic tube intermediate between the microphone and the sound pick-up element, while FIG. 3 shows the embodiment which provides for housing the microphone directly in front of the sound pickup element.

Le schéma en fig. 1 permet de se rendre compte de l'avantage réalisé par l'aménagement suivant l'invention de l'assise pour le dispositif de mesure. En effet ce dernier se trouve à l'abri des sources majeures d'endommagement tout en gardant un accès vers les sources du bruit qu'il s'agit de capter. Le fait d'encastrer le dispositif de mesure dans la tuyauterie de refroidissement de la cheminée de la manière décrite permet en plus de contourner les difficultés qui pourraient survenir lors d'opérations de nettoyage au cas où le système serait logé de manière indépendante dans le cheminée, p.ex. par suspension. En effet le système constituerait dans ce cas un obstacle et ne manquerait pas d'être endommagé au cours des opérations de nettoyage qui se déroulent nécessairement dans des conditions rudes.The diagram in fig. 1 shows the advantage achieved by the arrangement according to the invention of the seat for the measuring device. In fact, the latter is sheltered from major sources of damage while retaining access to the sources of the noise to be picked up. The fact of embedding the measuring device in the cooling pipe of the chimney in the manner described also makes it possible to circumvent the difficulties which could arise during cleaning operations in the event that the system is housed independently in the chimney. , eg by suspension. Indeed the system would constitute in this case an obstacle and would not fail to be damaged during the cleaning operations which necessarily take place in harsh conditions.

On distingue sur le schéma d'une coupe à travers le creuset (O) et la cheminée (1), ainsi que la couronne cylindrique qu'elle.. est formée par les tuyaux de refroidissement (10). Il est bien entendu que la dimension de la couronne est exagérée sur le dessin, par rapport à la dimension de la cheminée et du creuset. Les tuyaux (10) visibles constituent une moitié du cylindre; l'autre moitié se trouvant de l'autre côté du plan de la feuille n'est pas représentée.We can see on the diagram a section through the crucible (O) and the chimney (1), as well as the cylindrical crown that it .. is formed by the cooling pipes (10). It is understood that the dimension of the crown is exaggerated in the drawing, compared to the dimension of the chimney and the crucible. The visible pipes (10) constitute one half of the cylinder; the other half on the other side of the sheet plane is not shown.

En fig. 2 on distingue 2 tuyaux (10) qui font partie de la couronne cylindrique et qui forment l'assise du sertissage (11). Ce dernier comprend utilement une double paroi pour le cas où un refroidissement, de préférence au gaz, semblerait nécessaire. A cette fin il est prévu une embouchure (12) pour l'introduction du gaz de refroidissement.In fig. 2 there are 2 pipes (10) which form part of the cylindrical crown and which form the seat of the crimping (11). The latter usefully includes a double wall in the event that cooling, preferably with gas, seems necessary. To this end there is provided a mouth (12) for the introduction of the cooling gas.

Au sertissage (11) est reliée la cellule circulaire (20) qui comporte un circuit de refroidissement à l'eau avec les embouchures d'entrée, resp. de sortie (21) resp. (22). La cellule (20) comporte un orifice central (23) d'un diamètre d'environ 100 mm. Entre la cellule (20) et le sertissage (11) se trouve un joint souple (24).To the crimp (11) is connected the circular cell (20) which has a water cooling circuit with the inlet mouths, resp. outlet (21) resp. (22). The cell (20) has a central orifice (23) with a diameter of about 100 mm. Between the cell (20) and the crimp (11) is a flexible seal (24).

La cellule (20) est à son tour reliée à l'enceinte (40) qui contient le capteur acoustique. Entre la cellule (20) et l' enceinte (40) se trouve l'élément de prise de son (30) qui est un disque dont la partie centrale forme un évasement en tromblon (31). Le disque (30) touche par-lune face la cellule cylindrique (20), ce qui a pour effet un certain refroidissement du disque (30). Il touche par son autre face un joint souple (25) interposé entre le disque (30) et la cellule (20).The cell (20) is in turn connected to the enclosure (40) which contains the acoustic sensor. Between the cell (20) and the enclosure (40) is the sound pickup element (30) which is a disc, the central part of which forms a blunt flare (31). The disc (30) touches the cylindrical cell (20) opposite each other, which has the effect of cooling the disc (30). Its other side touches a flexible seal (25) interposed between the disc (30) and the cell (20).

L'ensemble cellule (20), disque (30), joint 125) et enceinte (40) est relié à l'aide des boulons (26).The cell (20), disc (30), seal 125) and enclosure (40) assembly is connected using the bolts (26).

L'enceinte (40) comprend le tube acoustique (50) qui est logé dans le tube (51) que traverse un courant d'azote (N2), qui s'échappe par l'orifice de la partie évasée (31) de l'élément de prise du son.The enclosure (40) comprises the acoustic tube (50) which is housed in the tube (51) through which a stream of nitrogen (N2) passes, which escapes through the orifice of the flared part (31) of the sound recording element.

Le tube (50) qui peut avoir une longueur supérieure à 3 m, conduit vers le microphone non-représenté.The tube (50) which may have a length greater than 3 m, leads to the microphone, not shown.

En fig. 3 est représenté essentiellement le même ensemble cellule (20), disque (30), joint (25), enceinte (40) comme en fig. 2. Or, la forme d'exécution représentée en fig. 3 où le microphone (60) est logé directement en face de l'élément de prise du son (30, 31), nécessite que l'enceinte (40) comprenne un circuit d'eau de refroidissement (41) spécial avec les embouchures (42) et (43). De même il est représenté l'embouchure pour l'azote (44), non-représenté en fig. 2.In fig. 3 shows essentially the same cell assembly (20), disc (30), seal (25), enclosure (40) as in fig. 2. However, the embodiment shown in fig. 3 where the microphone (60) is housed directly opposite the sound pickup element (30, 31), requires that the enclosure (40) include a special cooling water circuit (41) with the mouthpieces ( 42) and (43). Similarly, the mouth for nitrogen (44) is shown, not shown in FIG. 2.

On distingue également le microphone (60) qui est protégé contre l'accès de poussières par la membrane (56). Cette dernière est protégée à son tour par la capsule perforée (55) qui met la membrane (56) à l'abri de la chaleur d'irradiation des flammes et d'éventuelles projections que le jet (N2) serait incapable d'écarter.There is also a microphone (60) which is protected against access of dust by the membrane (56). The latter is in turn protected by the perforated capsule (55) which protects the membrane (56) from the heat of irradiation of the flames and from any projections that the jet (N2) would be unable to remove.

Plusieurs bagues toroidales (70) assurent que les distances respectives entre la capsule perforée (55) et la membrane (56) et entre la membrane (56) et le microphone (60) soient constantes et reproductibles. A cette même fin le microphone (60) est maintenu en place à l'aide d'un ressort (57).Several toroidal rings (70) ensure that the respective distances between the perforated capsule (55) and the membrane (56) and between the membrane (56) and the microphone (60) are constant and reproducible. For this same purpose the microphone (60) is held in place by means of a spring (57).

La partie terminale de l'enceinte (40) est fermée à l'aide d'un rembourrage en matière plastique.The terminal part of the enclosure (40) is closed by means of a plastic padding.

Suivant l'invention il suffit des isolations souples (24) en fig. 2 et (25) en fig. 2 et en fig. 3 pour supprimer en grande partie les vibrations et chocs mécaniques. Il est bien entendu par ailleurs que la partie électronique du système de mesure suivant l'invention comporte plusieurs filtres qui éliminent les bruits de fréquences indésirables dans le présent contexte et qui ne laissent subsister que les sons qui entrent en ligne de compte pour les mesures à effectuer.According to the invention, flexible insulations (24) in FIG. 2 and (25) in fig. 2 and in fig. 3 to largely eliminate mechanical vibrations and shocks. It is understood, moreover, that the electronic part of the measurement system according to the invention comprises several filters which eliminate noise of undesirable frequencies in the present context and which leave only the sounds which are taken into account for the measurements to be taken. carry out.

Claims (14)

1) Système de mesure pour la détermination du niveau et pour l'appréciation de l'état physique de la scorie dans un récipient métallurgique, notamment dans un convertisseur d'aciérie à soufflage d'oxygène, lequel système exploite le principe de la mesure de l'intensité du son engendré par la lance de soufflage, caractérisé en ce qu'un nombre suffisant de tuyaux du système de refroidissement installé dans la cheminée au-dessus du creuset comportent une rallonge et forment une couronne cylindrique qui saillit vers l'extérieur de l'enveloppe de la cheminée et dont l'axe est incliné vers le centre du creuset, laquelle couronne forme l'assise d'un sertissage cylindrique relié à une cellule circulaire à double paroi refroidie à l'eau et munie d'un orifice central, à laquelle cellule est reliée l'enceinte qui contient le capteur acoustique proprement dit.1) Measuring system for determining the level and for assessing the physical state of the slag in a metallurgical vessel, in particular in an oxygen blowing steelworks converter, which system exploits the principle of measuring the intensity of the sound generated by the blowing lance, characterized in that a sufficient number of pipes of the cooling system installed in the chimney above the crucible comprise an extension and form a cylindrical crown which projects outwards the envelope of the chimney and whose axis is inclined towards the center of the crucible, which crown forms the seat of a cylindrical crimp connected to a circular double-walled cell cooled with water and provided with a central orifice , to which cell is connected the enclosure which contains the actual acoustic sensor. 2) Système de mesure suivant la revendication 1, caractérisé en ce que le capteur acoustique est un microphone auquel est relié un ensemble électronique qui comporte des filtres passe-bandes et qui assure le traitement des signaux captés, ainsi que leur conversion en informations significatives, soit pour l'opérateur, soit pour le processeur automatique qui conduit le,processus de l'affinage2) Measuring system according to claim 1, characterized in that the acoustic sensor is a microphone to which is connected an electronic assembly which includes bandpass filters and which ensures the processing of the signals picked up, as well as their conversion into significant information, either for the operator or for the automatic processor which conducts the refining process 3) Système de mesure suivant les revendications 1-2, caractérisé en ce qu'un élément de prise du son est intercalé entre l'enceinte et la cellule circulaire.3) Measuring system according to claims 1-2, characterized in that a sound pickup element is interposed between the enclosure and the circular cell. 4) Système de mesure suivant les revendications 1-3, caractérisé en ce que l'élément de prise du son est un disque dont la partie centrale évasée en tromblon est dirigée vers la source du bruit à capter et se trouve à l'intérieur de l'orifice central de la cellule circulaire.4) Measuring system according to claims 1-3, characterized in that the sound pick-up element is a disc the central part of which is flared in a blunderbuss pattern is directed towards the source of the noise to be picked up and is located inside the central opening of the circular cell. 5) Système de mesure suivant les revendications 1-4, caractérisé en ce que le disque s'appuie d'une part contre la cellule circulaire et d'autre part par l'intermédiaire d'un joint souple, contre l'enceinte qui contient le capteur acoustique.5) Measuring system according to claims 1-4, characterized in that the disc bears on the one hand against the cel lule circular and on the other hand by means of a flexible joint, against the enclosure which contains the acoustic sensor. 6) Système de mesure suivant les revendications 1-5, caractérisé en ce qu'un tube acoustique logé dans l'enceinte est intercalé entre le microphone et l'élément de prise du son.6) Measuring system according to claims 1-5, characterized in that an acoustic tube housed in the enclosure is interposed between the microphone and the sound pickup element. 7) Système de mesure suivant les revendications 1-5, caractérisé en ce que le microphone est logé directement dans l'enceinte, en face de l'élément de prise du son.7) Measuring system according to claims 1-5, characterized in that the microphone is housed directly in the enclosure, opposite the sound pickup element. 8) Système de mesure suivant les revendications 1-5, et 7, caractérisé en ce que le microphone est logé dans un tube qui porte à son extrémité en face de l'élément de prise du son un bouchon perforé.8) Measuring system according to claims 1-5, and 7, characterized in that the microphone is housed in a tube which carries at its end opposite the sound pickup element a perforated plug. 9) Système de mesure suivant les revendications 1-5 et 7-8, caractérisé en ce qu'entre le bouchon perforé et le microphone se trouve une membrane d'une épaisseur d'environ 0,1 mm.9) Measuring system according to claims 1-5 and 7-8, characterized in that between the perforated plug and the microphone is a membrane with a thickness of about 0.1 mm. 10) Système de mesure suivant les revendications 1-5 et 7-9, caractérisé en ce que les distances entre le bouchon perforé et la membrane, resp. entre la membrane et le microphone, sont définies et reproductibles.10) Measuring system according to claims 1-5 and 7-9, characterized in that the distances between the perforated plug and the membrane, resp. between the membrane and the microphone, are defined and reproducible. 11) Système de mesure suivant les revendications 1-10, caractérisé en ce que l'enceinte qui contient le capteur est refroidie à l'aide d'un gaz neutre, de préférence de l'azote, qui est introduit en arrière de l'enceinte et qui sort par la partie évasée de l'élément dé prise du son.11) Measuring system according to claims 1-10, characterized in that the enclosure which contains the sensor is cooled using a neutral gas, preferably nitrogen, which is introduced behind the enclosure and which leaves through the flared part of the sound pickup element. 12) Système de mesure suivant les revendications 1-5 et 7-10, caractérisé en ce que l'enceinte-comporte un circuit de refroidissement à l'eau d'une température inférieure à 15°C.12) Measuring system according to claims 1-5 and 7-10, characterized in that the enclosure-comprises a water cooling circuit with a temperature below 15 ° C. 13) Système de mesure suivant les revendications 1-12, caractérisé en ce que la cellule circulaire comporte un circuit d'eau de refroidissement.13) Measuring system according to claims 1-12, characterized in that the circular cell comprises a circuit cooling water. 14) Système de mesure suivant les revendications 1-13, caractérisé en ce que le sertissage qui entoure la couronne cylindrique comporte un circuit de gaz de refroidissement14) Measuring system according to claims 1-13, characterized in that the crimping which surrounds the cylindrical ring comprises a cooling gas circuit
EP80630037A 1979-09-28 1980-08-28 System for measuring the height of the slag in a metallurgical vessel, and for determining its physical condition Expired EP0029796B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT80630037T ATE8800T1 (en) 1979-09-28 1980-08-28 SYSTEM FOR DETERMINING THE HEIGHT AND PHYSICAL CONDITION OF SLAG IN A METALLURGICAL VESSEL.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
LU81740A LU81740A1 (en) 1979-09-28 1979-09-28 SYSTEM FOR MEASURING THE THICKNESS OF THE SLAG LAYER IN A METALLURGICAL CONTAINER AND FOR THE ASSESSMENT OF ITS PHYSICAL STATE
LU81740 1979-09-28

Publications (2)

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EP0029796A1 true EP0029796A1 (en) 1981-06-03
EP0029796B1 EP0029796B1 (en) 1984-08-01

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EP80630037A Expired EP0029796B1 (en) 1979-09-28 1980-08-28 System for measuring the height of the slag in a metallurgical vessel, and for determining its physical condition

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US (1) US4368877A (en)
EP (1) EP0029796B1 (en)
JP (1) JPS5658917A (en)
AT (1) ATE8800T1 (en)
AU (1) AU539411B2 (en)
BR (1) BR8005978A (en)
CA (1) CA1159946A (en)
DE (1) DE3068798D1 (en)
ES (1) ES495369A0 (en)
LU (1) LU81740A1 (en)
ZA (1) ZA805866B (en)

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KR100406371B1 (en) * 1998-12-24 2004-01-24 주식회사 우진 Apparatus and method for detecting thickness of slag layer in ladle
US6805831B2 (en) * 2002-05-10 2004-10-19 Luis Paredes Rojas Mechanical waves generator system in a converter or pyrometallurgical furnace
US6787099B2 (en) * 2002-05-10 2004-09-07 Luis Paredes Rojas Mechanical waves generator system in a converter or pyrometallurgical furnace
US6790406B2 (en) * 2002-05-10 2004-09-14 Luis Paredes Rojas Mechanical waves generator system in a converter or pyrometallurgical furnace
US6836734B2 (en) * 2002-05-13 2004-12-28 Luis Paredes Rojas System for a non-invasive online discrete measurement of phase levels in converters or pyrometallurgical furnaces
US6786082B2 (en) * 2002-05-13 2004-09-07 Luis Paredes Rojas System for a non-invasive online continuous measurement of phase levels in converters or pyrometallurgical furnaces
US6792358B2 (en) * 2002-05-13 2004-09-14 Luis Paredes Rojas System for a non-invasive online continuous measurement of phrase levels in converters or pyrometallurgical furnaces
KR100671673B1 (en) * 2005-03-09 2007-01-19 삼성에스디아이 주식회사 Device and Method for vacuum plating by Multiple evaporation
EP1918703B1 (en) * 2007-02-07 2015-06-24 Tata Steel UK Limited Acoustic emission control of slag height in a steelmaking process
KR100905583B1 (en) * 2007-12-27 2009-07-02 주식회사 포스코 Method for Measuring Thickness of Slag and Method for Desulfurizing Molten Steel Using Noise Value

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Also Published As

Publication number Publication date
DE3068798D1 (en) 1984-09-06
ES8106809A1 (en) 1981-08-01
ZA805866B (en) 1981-09-30
ATE8800T1 (en) 1984-08-15
BR8005978A (en) 1981-03-31
AU539411B2 (en) 1984-09-27
LU81740A1 (en) 1981-04-17
AU6278580A (en) 1982-03-18
JPS5658917A (en) 1981-05-22
EP0029796B1 (en) 1984-08-01
US4368877A (en) 1983-01-18
CA1159946A (en) 1984-01-03
ES495369A0 (en) 1981-08-01

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