EP0056777A2 - Control and regulatory process for continuously casting belts between rolls in order to avoid sticking - Google Patents
Control and regulatory process for continuously casting belts between rolls in order to avoid sticking Download PDFInfo
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- EP0056777A2 EP0056777A2 EP82420009A EP82420009A EP0056777A2 EP 0056777 A2 EP0056777 A2 EP 0056777A2 EP 82420009 A EP82420009 A EP 82420009A EP 82420009 A EP82420009 A EP 82420009A EP 0056777 A2 EP0056777 A2 EP 0056777A2
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- frequency
- speed
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
- B22D11/16—Controlling or regulating processes or operations
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
- B22D11/06—Continuous casting of metals, i.e. casting in indefinite lengths into moulds with travelling walls, e.g. with rolls, plates, belts, caterpillars
- B22D11/0622—Continuous casting of metals, i.e. casting in indefinite lengths into moulds with travelling walls, e.g. with rolls, plates, belts, caterpillars formed by two casting wheels
Definitions
- the present invention relates to a process for controlling and regulating the operating parameters of a machine for casting strips between rolls, making it possible to avoid sticking and to obtain maximum productivity.
- the metal distributed by the nozzle fills the free space between the cylinders all along an arc of circle included between the plane of the outlet section of the nozzle and the plane of exit of the cylinders .
- the metal cools, begins to solidify in a place called swamp, due to the presence of a more or less viscous mixture of crystals and liquid, located at a distance from the plane of the section outlet point of the nozzle generally called marsh depth. Then, the metal solidifies completely and is driven towards the exit plane of the cylinders in an increasingly restricted space, where it undergoes a rolling force which gradually brings it to the desired thickness when it escapes. by the space between cylinders in the form of a strip which is then taken up by a reel.
- This strip is subsequently subjected to various mechanical and / or thermal treatments which lead to products such as thin sheets, for example, the mechanical characteristics of which: resistance, elastic limit, elongation, hardness, etc. will be part depending on the quality of the strip from the casting machine.
- casting machines are used at speeds clearly lower than their possibility, so as to avoid the appearance of sticking, whatever the possible variations of the working factors.
- This process in which the torque exerted on one or the other of the cylinders to advance the strip is used as parameters, and not the total torque, is characterized in that the frequency of the variations in the measurement is constantly compared. torque at a reference frequency; when the frequency of the variations is higher than the reference frequency, the casting speed of the machine is reduced and / or the die bit of lubricant is increased until the frequency of the variations becomes lower than the reference frequency and remains in this state for a given time, then the casting speed is increased as long as the frequency of the variations remains lower than the frequency reference.
- the method according to the invention consists first of all in considering as a running parameter only the torque exerted on one or the other of the cylinders to advance the strip.
- This parameter comes from the fact that it has been observed that, when the strip is bonded to one of the cylinders, almost all of the torque is supported by the opposite cylinder without appreciably affecting the total torque, which, in the absence of bonding, is distributed approximately equally between the two cylinders. It is therefore sufficient to consider one or the other of these couples to detect the sudden variation corresponding to the appearance of a collage. However, it may seem, under these conditions, that the process is limited to a rapid grasp of the phenomenon and an intervention aimed at eliminating it, which would not prevent the appearance of a defect on the tape and would lead in spite of everything to a partial scrap.
- the method aims to provide for bonding and to provide the means to react before the defect has been able to manifest itself.
- the speed reduction is obtained, for example, by varying the direct supply voltage of the cylinder drive motor; the lubricant flow is changed, for example, by a different setting of the intake valves.
- This intervention does not occur immediately after the detection of a signal indicating that the frequency of the torque variations exceeds the reference frequency, but when this signal has been maintained for approximately five seconds, this so as to eliminate the fleeting increases which may occur and which are due to transient variations in certain walking parameters unrelated to the bonding phenomenon.
- Reducing or increasing the machine speed can be done gradually or in fixed time steps.
- the speed can be reduced for periods of time less than five minutes, by an amount less than 15% of the value it had at the instant immediately prior.
- the invention will be better understood using the single figure representing a type of machine and on which one can see a supply rod (1) by which the liquid metal is admitted between the two cylinders (2 and 2 ') whose pins (3 and 4) are held by the chocks (5 and 6) integral with the column (7).
- the two cylinders have their surface lubricated by means of the distribution ramps (8 and 8 ') supplied with lubricant by the valves (9 and 9'). After cooling and rolling, the metal leaves the machine in the form of a strip (10) which is wound in (11).
- the cylinders are rotated in opposite directions by means of a motor (12).
- the torque measurement on one of the cylinders is detected by means of the strain gauge (13). This measurement is transmitted to the computer (14) which controls in (15) the speed of the motor by modifying the voltage of the supply current and in (16 and 16 ') the admission of lubricant to the ramps via the valves ( 9 and 9 ').
- a 1235 alloy is poured, the composition of which is described in "Standard for Aluminum Mill Products" published by ALUMINUM ASSOCIATION in the form of a strip 8 mm thick with a speed of 1.30 m / min and a lubricant flow of 10 1 / hour by means of a machine of the SCAL JUMBO 3C type equipped with a PERKIN ELMER 1620 mini-computer.
- the speed of the machine and the valves admission of the lubricant not being controlled by the computer, the torque exerted on the lower cylinder is constantly measured by means of an extensometry gauge glued to the journal and sends the signal to an electronic device making it possible to directly detect the variations of the torque and also to electronically filter this signal so as to retain only those whose frequency is greater than one Hertz.
- the registration of. signals before filtration shows variations on either side of an average value of the period couple of the order of 30 seconds while the filtered signal indicator remains at zero.
- the strip After the strip has been discarded, it is replaced under the same operating conditions as above, that is to say a casting speed of 1.3 m / min and a lubricant flow rate of 10 1 / hour and it is controlled by the using the microcomputer according to the invention, the speed of the machine and the lubricant inlet valves at the indications of the filter signal. After 15 minutes When running, a frequency of variation of the torque measurement close to 3 hertz is detected. The lubricant flow is then automatically increased to 11 1 / hour and the casting speed reduced by 0.05 m / min. After a few seconds, the frequency of the variations returned to normal and the filtered signal zero. After five minutes of walking under these conditions, the speed is gradually increased to 1.4 m / min and the casting is continued at this speed without the appearance of new micro-bonding even after several hours of casting.
- the method according to the invention finds its application in the continuous casting of metals between cylinders in all cases where it is desired to avoid sticking of the strip on the cylinders and to keep the machine running under conditions of maximum productivity.
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Continuous Casting (AREA)
- Injection Moulding Of Plastics Or The Like (AREA)
- Sewing Machines And Sewing (AREA)
- Preliminary Treatment Of Fibers (AREA)
- Shaping By String And By Release Of Stress In Plastics And The Like (AREA)
- Metal Rolling (AREA)
- Basic Packing Technique (AREA)
- Preparation Of Compounds By Using Micro-Organisms (AREA)
- Saccharide Compounds (AREA)
- Peptides Or Proteins (AREA)
- Moulds For Moulding Plastics Or The Like (AREA)
- Moulding By Coating Moulds (AREA)
- Controlling Rewinding, Feeding, Winding, Or Abnormalities Of Webs (AREA)
Abstract
Description
La présente invention a pour objet un procédé de contrôle et de régulation de paramètres de marche d'une machine de coulée de bandes entre cylindres, permettant d'éviter le collage et d'obtenir une productivité maximum.The present invention relates to a process for controlling and regulating the operating parameters of a machine for casting strips between rolls, making it possible to avoid sticking and to obtain maximum productivity.
L'homme de l'art connaît les machines de coulée à moule mobile du type à cylindres qui sont utilisées pour fabriquer directement, à partir d'une masse métallique en fusion, une bande continue ayant une largeur pouvant atteindre quelques mètres et une épaisseur voisine du centimètre .Those skilled in the art are familiar with movable mold casting machines of the cylinder type which are used to directly manufacture, from a molten metal mass, a continuous strip having a width of up to a few meters and a thickness close to it. of the centimeter.
Ces machines sont constituées principalement :
- - d'une part, d'un dispositif d'alimentation en métal liquide comprenant successivement dans le sens d'écoulement du métal :
- . un four de maintien du métal à l'état liquide,
- . une goulotte de circulation équipée d'un système réglant le niveau et le débit du métal,
- . une busette de répartition du métal ayant à son extrémité de sortie une ouverture de section rectangulaire ;
- - d'autre part, un dispositif de refroidissement et de laminage comprenant deux cylindres dont les axes sont parallèles et espacés plus ou moins l'un de l'autre suivant l'épaisseur de bande désirée. Ces cylindres sont munis, à chacune de leurs extrémités, de prolongements cylindriques axiaux ou tourillons qui s'engagent par l'intermédiaire de coussinets dans des ouvertures pratiquées dans des traverses support ou empoises, équipées d'un système de serrage et solidaires de deux colonnes verticales qui forment le bâti de la machine ; ils sont munis in- térieurement d'un réseau de canaux le long desquels circule un fluide de refroidissement et sont en relation, par l'intemédiaire d'allonges, avec un moteur qui les anime d'un mouvement de rotation en sens inverse. La surface extérieure de ces cylindres est arrosée régulièrement de lubrifiant au moyen d'un système de pulvérisation convenable.
- - on the one hand, of a liquid metal supply device comprising successively in the direction of flow of the metal:
- . an oven for maintaining the metal in the liquid state,
- . a circulation chute equipped with a system regulating the level and the flow of metal,
- . a metal distribution nozzle having at its outlet end an opening of rectangular section;
- - On the other hand, a cooling and rolling device comprising two cylinders whose axes are parallel and more or less spaced from each other according to the desired strip thickness. These cylinders are provided, at each of their ends, with axial cylindrical extensions or trunnions which engage by means of bearings in openings made in support crosspieces or chocks, equipped with a clamping system and integral with two columns verticals which form the frame of the machine; they are provided i n - térieurement a network of channels along which a cooling fluid and are connected, by the extensions intemédiaire, with an engine that animates a reverse rotation movement. The outer surface of these cylinders is regularly sprayed with lubricant by means of a suitable spraying system.
Ces deux dispositifs sont placés l'un par rapport à l'autre, de telle manière que la section de sortie de la busette soit parallèle aux axes des cylindres et située à une certaine distance du plan passant par ces axes qu'on appelle plan de sortie.These two devices are placed in relation to each other, so that the outlet section of the nozzle is parallel to the axes of the cylinders and located at a certain distance from the plane passing through these axes which is called the exit plane.
Lors du fonctionnement de la machine, le métal réparti par la busette, remplit l'espace libre entre les cylindres tout au long d'un arc de cercle compris entre le plan de la section de sortie de la busette et le plan de sortie des cylindres.During the operation of the machine, the metal distributed by the nozzle, fills the free space between the cylinders all along an arc of circle included between the plane of the outlet section of the nozzle and the plane of exit of the cylinders .
Sous l'action des cylindres, le métal se refroidit, commence à se solidifier en un endroit appelé marais, en raison de la présence d'un mélange plus ou moins visqueux de cristaux et de liquide, situé à une distance du plan de la section de sortie de la busette dite généralement profondeur de marais. Puis, le métal se solidifie complétement et est entraîné vérs le plan de sortie des cylindres dans un espace de plus en plus restreint, où il subit un effort de laminage qui l'amène progressivement à l'épaisseur voulue au moment où il s'échappe par l'espace entre cylindres sous forme d'une bande qui est alors reprise par un enrouleur.Under the action of the cylinders, the metal cools, begins to solidify in a place called swamp, due to the presence of a more or less viscous mixture of crystals and liquid, located at a distance from the plane of the section outlet point of the nozzle generally called marsh depth. Then, the metal solidifies completely and is driven towards the exit plane of the cylinders in an increasingly restricted space, where it undergoes a rolling force which gradually brings it to the desired thickness when it escapes. by the space between cylinders in the form of a strip which is then taken up by a reel.
Cette bande est soumise, par la suite, à différents traitements mécaniques et/ou thermiques qui conduisent à des produits tels que feuilles minces, par exemple, dont les caractéristiques mécaniques : résistance, limite élastique, allongement, dureté, etc... seront en partie fonction de la qualité de la bande issue de la machine de coulée..This strip is subsequently subjected to various mechanical and / or thermal treatments which lead to products such as thin sheets, for example, the mechanical characteristics of which: resistance, elastic limit, elongation, hardness, etc. will be part depending on the quality of the strip from the casting machine.
Il est donc important d'essayer de maintenir une bonne qualité du début à la fin de la coulée de la bande. Pour cela, il faut faire fonctionner la machine dans les conditions les plus favorables à l'obtention d'un tel résultat, même lorsqu'on l'utilise à sa vitesse maximum.It is therefore important to try to maintain good quality from the start to the end of the tape casting. For this, the machine must be operated under the conditions most favorable for obtaining such a result, even when it is used at its maximum speed.
Une bonne qualité suppose l'absence de défauts tels que criques, fissures ou coulure de métal à la sortie des cylindres et la demande de brevet principal n° 80 19162 enseigne un procédé de contrôle et de régulation permettant de répondre à ce besoin, dans lequel on utilise comme paramètres de marche, les efforts de laminage, le couple total nécessaire à l'entraînement de la bande et la température à la sortie de la bande. Cependant, un tel procédé ne tient pas compte des phénomènes de collage qui peuvent se produire entre cylindres et produit coulé et persister au-delà du plan de sortie des cylindres, en provoquant l'apparition de défauts plus ou moins importants sur la bande et la nécessité parfois dé la rebuter.Good quality presupposes the absence of faults such as cracks, cracks or sagging of metal at the outlet of the cylinders and the main patent application n ° 80 19162 teaches a control and regulation process making it possible to meet this need, in which as running parameters, the rolling forces, the total torque necessary for driving the strip and the temperature at the exit of the strip are used. However, such a method does not take account of the bonding phenomena which can occur between cylinders and cast product and persist beyond the exit plane of the cylinders, causing the appearance of more or less significant defects on the tape and the need sometimes to discard it.
Les causes de ce collage sont à la fois liées à la vitesse de coulée et au débit de lubrifiant pulvérisé sur les cylindres. En effet, on a constaté qu'au-delà de certaines vitesses, la tendance au collage devenait plus critique. Pour y parer, on peutcertesaugmenter le débit de lubrifiant, mais l'homme de l'art sait qu'une lubrifïcation trop abondante risque de détériorer l'échange thermique entre le métal coulé et la surface des cylindres et de conduire à la formation de coulures. Aussi, est-on alors amené à réduire la vitesse de la machine et à diminuer, ainsi sa productivité. D'où la nécessité de trouver des conditions optimum de débit de lubrifiant et de vitesse de coulée, qui permettent à la machine de travailler à son maximum tout en évitant le collage. On peut penser fixer ces conditions une fois pour toutes, mais elles ne sont pas stables dans le temps car elles sont fonction de nombreux facteurs variables tels que homogénéité, température et niveau du métal liquide, température et état de surface des cylindres, facteurs pour lesquels le contrôle et le réglage d'ensemble en continu est difficile et, pour certains d'entre eux, impossible.The causes of this sticking are linked both to the speed of casting and to the flow of lubricant sprayed on the cylinders. In fact, it has been observed that beyond certain speeds, the tendency to stick becomes more critical. To counter this, it is certainly possible to increase the flow of lubricant, but those skilled in the art know that too abundant lubrication risks deteriorating the heat exchange between the cast metal and the surface of the cylinders and leading to the formation of drips. . Also, is it then necessary to reduce the speed of the machine and thus decrease its productivity. Hence the need to find optimum conditions for lubricant flow and casting speed, which allow the machine to work at its maximum while avoiding sticking. We can think of fixing these conditions once and for all, but they are not stable over time because they are a function of many variable factors such as homogeneity, temperature and level of the liquid metal, temperature and surface condition of the cylinders, factors for which continuous monitoring and adjustment is difficult and, for some of them, impossible.
Aussi, le plus souvent, les machines de coulée sont utilisées à des vitesses nettement inférieures à leur possibilité, de façon à éviter l'apparition de collage, quelles que soient les éventuelles variations des facteurs de marche.Also, more often than not, casting machines are used at speeds clearly lower than their possibility, so as to avoid the appearance of sticking, whatever the possible variations of the working factors.
C'est pourquoi, la demanderesse a étudié et mis au point un procédé de contrôle et de régulation des paramètres de marche de la machine de coulée permettant d'éviter le collage tout en maintenant une productivité maximum.This is why the applicant has studied and developed a process for controlling and regulating the operating parameters of the casting machine, making it possible to avoid sticking while maintaining maximum productivity.
Ce procédé dans lequel on utilise comme paramètres le couple exercé sur l'un ou l'autre des cylindres pour faire avancer la bande et non le couple total, est caractérisé en ce que l'on compare en permanence la fréquence des variations de la mesure du couple à une fréquence de référence ; lorsque la fréquence des variations est supérieure à la fréquence de référence, la vitesse de coulée de la machine est réduite et/ou le débit de lubrifiant est augmente jusqu'à ce que la fréquence des variations redevienne inférieure à la fréquence de référence et se maintienne en cet état pendant un temps donné, puis la vitesse de coulée est augmentée tant que la fréquence des variations demeure inférieure à la fréquence de référence.This process, in which the torque exerted on one or the other of the cylinders to advance the strip is used as parameters, and not the total torque, is characterized in that the frequency of the variations in the measurement is constantly compared. torque at a reference frequency; when the frequency of the variations is higher than the reference frequency, the casting speed of the machine is reduced and / or the die bit of lubricant is increased until the frequency of the variations becomes lower than the reference frequency and remains in this state for a given time, then the casting speed is increased as long as the frequency of the variations remains lower than the frequency reference.
Ainsi, le procédé selon l'invention consiste d'abord à ne considérer comme paramètre de marche que le couple exercé sur l'un ou.l'autre des cylindres pour faire avancer la bande. L'utilisation de ce paramètre :: vient du fait que l'on a constaté que, lors d'un collage de la bande sur un des cylindres, la quasi totalité du couple est supportée par le cylindre opposé sans affecter sensiblement le couple total, lequel, en l'absence de collage, se répartit de façon à peu près égale entre les deux cylindres. Il suffit donc de considérer l'un ou l'autre de ces couples pour détecter la brusque variation correspondant à l'apparition d'un collage. Toutefois, il peut sembler, dans ces conditions, que le procédé se trouve limité à une saisie rapide du phénomène et à une intervention visant à le supprimer, ce qui n'empêcherait pas l'apparition d'un défaut sur la bande et conduirait malgré tout à un rebut partiel.Thus, the method according to the invention consists first of all in considering as a running parameter only the torque exerted on one or the other of the cylinders to advance the strip. The use of this parameter :: comes from the fact that it has been observed that, when the strip is bonded to one of the cylinders, almost all of the torque is supported by the opposite cylinder without appreciably affecting the total torque, which, in the absence of bonding, is distributed approximately equally between the two cylinders. It is therefore sufficient to consider one or the other of these couples to detect the sudden variation corresponding to the appearance of a collage. However, it may seem, under these conditions, that the process is limited to a rapid grasp of the phenomenon and an intervention aimed at eliminating it, which would not prevent the appearance of a defect on the tape and would lead in spite of everything to a partial scrap.
En fait, le procédé vise à prévoir le collage et à donner les moyens de réagir avant même que le défaut ait pu se manifester.In fact, the method aims to provide for bonding and to provide the means to react before the defect has been able to manifest itself.
Ceci a été permis grâce à des observations de. la demanderesse et montrant que, avant la formation d'un collage préjudiciable à l'état de la bande, il se produit d'abord un micro-collage se limitant à une surface très petite de part et d'autre d'une génératrice d'un des cylindres et qui ne nuit pas à la qualité de la bande, puis, un décollement immédiat suivi d'un nouveau micro-collage, et ainsi de suite jusqu'au collage généralisé se produisant en général après une rotation du cylindre de un ou plusieurs tours. Il fallait donc pouvoir saisir de tels micro-colla- - ges pour en prévenir la généralisation. Ici encore, la demanderesse a mis en évidence le fait qu'en marche normale, la valeur du couple mesurée sur l'un des cylindres fluctuait suivant une période longue de l'ordre de quelques dizaines de secondes alors que, si des micro-collages apparaissent, cette période diminue sensiblement conduisant à des valeurs inférieures à une seconde.This was made possible through observations from. the Applicant and showing that, before the formation of a bonding detrimental to the state of the strip, there first occurs a micro-bonding limited to a very small surface on either side of a generator d '' one of the cylinders and which does not harm the quality of the strip, then, an immediate peeling followed by a new micro-bonding, and so on until the generalized bonding generally occurring after a rotation of the cylinder by one or more rounds. It was therefore necessary to be able to grasp such micro-collages - to prevent their generalization. Here again, the Applicant has highlighted the fact that in normal operation, the value of the torque measured on one of the cylinders fluctuates over a long period of the order of a few tens of seconds whereas, if micro-bonding appear, this period decreases appreciably leading to values lower than one second.
Il suffisait, donc, pour saisir le micro-collage, de détectér cette diminution de période de fluctuation, en la comparant à une période de référence de l'ordre de la seconde, ou encore, puisque la période est l'inverse de la fréquence, de prendre cette dernière comme élément de mesure et de la comparer à une fréquence de l'ordre du Hertz.It was enough, therefore, to grasp the micro-bonding, to detect this reduction in the fluctuation period, by comparing it to a reference period of the order of a second, or again, since the period is the inverse of the frequency , take the latter as a measurement element and compare it with a frequency of the order of Hertz.
Ceci a été fait pratiquement en filtrant en fréquence au moyen de condensateurs, le signal électrique donné par une jauge d'extensométrie placée par exemple sur l'allonge d'uncylindre ou sur l'un des tourillons de la machine. Mais, on pourrait aussi employer les indications d'un. frëquen- ce-mètre ou tout autremoyen convenable. En marche normale, le signal filtré est à peu près constant et nul puisque la fréquence de variation est inférieure au Hertz. Par contre, dès que des micro-collages apparaissent, le signal filtré s'écarte de façon sensible de la valeur 0 et oscille avec une certaine fréquence alors qu'une variation de l'intensité du moteur d'entraînement des cylindres, et donc du couple total, n'est pas mesurable.This was practically done by filtering in frequency by means of capacitors, the electrical signal given by an extensometry gauge placed for example on the extension of a cylinder or on one of the pins of the machine. But, one could also use the indications of one. frequency meter or any other suitable means. In normal operation, the filtered signal is almost constant and zero since the frequency of variation is less than the Hertz. On the other hand, as soon as micro-bondings appear, the filtered signal deviates appreciably from the value 0 and oscillates with a certain frequency while a variation of the intensity of the drive motor of the cylinders, and therefore of the total torque is not measurable.
Etant ainsi prévenu de la formation prochaine du défaut, il faut pouvoir en éviter l'apparition. Pour cela, on agit en diminuant la vitesse de. coulée et/ou en augmentant le débit de lubrifiant.Being thus warned of the imminent formation of the defect, it must be possible to avoid its appearance. To do this, we act by decreasing the speed of. pouring and / or increasing the lubricant flow.
La réduction de vitesse est obtenue, par exemple, en jouant sur la tension continue d'alimentation du moteur d'entraînement des cylindres ; le débit de lubrifiant est modifié, par exemple, par un réglage différent des vannes d'admission. Cette intervention ne se produit pas immédiatement après la détection d'un signal indiquant que la fréquence des variations du couple dépasse la fréquence de référence, mais lorsque ce signal s'est maintenu pendant environ cinq secondes, ceci de manière à écarter les accroissements fugaces qui peuvent se produire et qui sont dûs à des variations passagères de certains paramètres de marche sans relation avec le phénomène de collage.The speed reduction is obtained, for example, by varying the direct supply voltage of the cylinder drive motor; the lubricant flow is changed, for example, by a different setting of the intake valves. This intervention does not occur immediately after the detection of a signal indicating that the frequency of the torque variations exceeds the reference frequency, but when this signal has been maintained for approximately five seconds, this so as to eliminate the fleeting increases which may occur and which are due to transient variations in certain walking parameters unrelated to the bonding phenomenon.
Ayant ainsi modifié les conditions de marche de la machine, soit les signes annonciateurs d'un collage persistent, auquel cas on procède à une nouvelle réduction de vitesse et/ou à un nouvel accroissement du débit de lubrifiant, soit, au contraire, ils disparaissent et on peut alors, au bout d'un temps donné de stabilité de l'ordre de une à quelques minutes, augmenter à nouveau la vitesse et ce, tant que la fréquence des variations demeure inférieure à la fréquence de référence.Having thus modified the machine's operating conditions, either the warning signs of sticking persist, in which case a further reduction in speed and / or a further increase in the lubricant flow rate, or, on the contrary, they disappear and we can then, at after a given time of stability of the order of one to a few minutes, increase the speed again, as long as the frequency of the variations remains below the reference frequency.
La réduction ou l'augmentation de la vitesse de la machine peut se faire progressivement ou par paliers de durée déterminée.Reducing or increasing the machine speed can be done gradually or in fixed time steps.
Ainsi, la vitesse peut être réduite pendant des périodes de temps inférieures à cinq minutes, d'une quantité inférieure à 15 % de la valeur qu'elle avait à l'instant immédiatement antérieur.Thus, the speed can be reduced for periods of time less than five minutes, by an amount less than 15% of the value it had at the instant immediately prior.
De même, elle peut être augmentée pendant des périodes de temps inférieures à cinq minutes d'une quantité inférieure à 10 % de sa valeur à un instant immédiatement antérieur.Likewise, it can be increased for periods of time less than five minutes by an amount less than 10% of its value at an instant immediately prior.
En ce qui concerne le lubrifiant, son débit êut être augmenté de 5 à 15 % de la valeur qu'il avait au moment où sont apparus les micro-collages.With regard to the lubricant, its flow rate could be increased by 5 to 15% of the value it had at the time when the micro-bondings appeared.
Les différentes fonctions : analyse des signaux émis par la jauge d'ex- tensométrie et leur utilisation au niveau de la vitesse de la machine ou des conditions de lubrification, sont exercées au moyen d'un calculateur du type ordinateur, miniordinateur, microprocesseur, ou automate programmable de type classique.The various functions: analysis of the signals emitted by the strain gauge and their use in terms of machine speed or lubrication conditions, are exercised by means of a computer of the computer, minicomputer, microprocessor, or classic type programmable controller.
L'invention sera mieux comprise à l'aide de la figure unique représentant un type de machine et sur laquelle on peut voir une bùsette d'alimentation (1) par laquelle le métal liquide est admis entre les deux cylindres (2 et 2') dont les tourillons (3 et 4) sont maintenus par les empoises (5 et 6) solidaires de la colonne (7). Les deux cylindres ont leur surface lubrifiée au moyen des rampes de distribution (8 et 8') alimentée en lubrifiant par les vannes (9 et 9'). Après refroidissement et laminage, le métal sort de la machine sous forme d'une bande (10) qui est enroulée en (11).The invention will be better understood using the single figure representing a type of machine and on which one can see a supply rod (1) by which the liquid metal is admitted between the two cylinders (2 and 2 ') whose pins (3 and 4) are held by the chocks (5 and 6) integral with the column (7). The two cylinders have their surface lubricated by means of the distribution ramps (8 and 8 ') supplied with lubricant by the valves (9 and 9'). After cooling and rolling, the metal leaves the machine in the form of a strip (10) which is wound in (11).
Les cylindres sont animés d'un mouvement de rotation en sens inverse au moyen d'un moteur (12).The cylinders are rotated in opposite directions by means of a motor (12).
On détecte, au moyen de la jauge d'extensométrie (13) la mesure du couple sur l'un des cylindres. Cette mesure est transmise au calculateur (14) qui commande en (15) la vitesse du moteur en modifiant la tension du courant d'alimentation et en (16 et 16') l'admission de lubrifiant aux rampes par l'intermédiaire des vannes (9 et 9').The torque measurement on one of the cylinders is detected by means of the strain gauge (13). This measurement is transmitted to the computer (14) which controls in (15) the speed of the motor by modifying the voltage of the supply current and in (16 and 16 ') the admission of lubricant to the ramps via the valves ( 9 and 9 ').
L'application de l'invention est illustrée par l'exemple suivant : On coule un alliage 1235 dont la composition est décrite dans "Standard for Aluminium Mill Products" publié par ALUMINIUM ASSOCIATION sous forme d'une bande de 8 mm d'épaisseur avec une vitesse de 1,30 m/mn et un débit de lubrifiant de 10 1/heure au moyen d'une machine du type SCAL JUMBO 3C équipéed'un mini-ordinateur PERKIN ELMER 1620. La vitesse de la machine et les vannes d'admission du lubrifiant n'étant pas contrôlés par l'ordinateur, on mesure en permanence le couple exercé sur le cylindre inférieur au moyen d'une jauge d'extensométrie collée sur le tourillon et envoie le signal sur un dispositif électronique permettant de détecter directement les variations du couple et également de filtrer électroniquement ce signal de manière à ne retenir que ceux dont la fréquence est supérieure à un Hertz. L'enregistrement des. signaux avant filtration montre des variations de part et d'autre d'une valeur moyenne du couple de période de l'ordre de 30 secondes alors que l'indicateur du signal filtré reste au zéro.The application of the invention is illustrated by the following example: A 1235 alloy is poured, the composition of which is described in "Standard for Aluminum Mill Products" published by ALUMINUM ASSOCIATION in the form of a strip 8 mm thick with a speed of 1.30 m / min and a lubricant flow of 10 1 / hour by means of a machine of the SCAL JUMBO 3C type equipped with a PERKIN ELMER 1620 mini-computer. The speed of the machine and the valves admission of the lubricant not being controlled by the computer, the torque exerted on the lower cylinder is constantly measured by means of an extensometry gauge glued to the journal and sends the signal to an electronic device making it possible to directly detect the variations of the torque and also to electronically filter this signal so as to retain only those whose frequency is greater than one Hertz. The registration of. signals before filtration shows variations on either side of an average value of the period couple of the order of 30 seconds while the filtered signal indicator remains at zero.
Après avoir coulé pendant dix minutes, on note un accroissement des variations de la mesure du couple dont la fréquence avoisine 3 hertz et l'indicateur de signal filtre s'écarte du zéro. Ce phénomène dure deux secondes, puis l'indicateur revient au zéro indiquant que la machine marche à nouveau dans les conditions normales. Au bout de quelques minutes, le même phénomène se reproduit pendant dix secondes et cesse à nouveau. Après quatre perturbations de ce genre, la mesure du couple croît brusquement et un collage généralisé se produit.After having run for ten minutes, there is an increase in the variations in the measurement of the torque, the frequency of which is around 3 hertz and the filter signal indicator deviates from zero. This phenomenon lasts two seconds, then the indicator returns to zero indicating that the machine is operating again under normal conditions. After a few minutes, the same phenomenon occurs for ten seconds and stops again. After four such disturbances, the measurement of the torque increases sharply and a generalized bonding occurs.
Après rebutage de la bande, on se replace dans les mêmes conditions de marche que précédemment, c'est-à-dire une vitesse de coulée de 1,3 m/mn et un débit de lubrifiant de 10 1/heure et on asservit au moyen du micro- ordinateur suivant l'invention, la vitesse de la machine et les vannes d'admission du lubrifiant aux indications du signal filtre. Après 15 minutes de marche, une fréquence de variation de la mesure du couple voisine de 3 hertz, est détectée. Le débit de lubrifiant est alors porté automatiquement à 11 1/heure et la vitesse de coulée réduite de 0,05 m/mn. Au bout de quelques secondes, la fréquence des variations est redevenue normale et le signal filtré nul. Après cinq minutes de marche dans ces conditions, la vitesse est réaugmentée progressivement jusqu'à 1,4 m/mn et la coulée est poursuivie à cette vitesse sans que l'on constate l'apparition de nouveaux microcollages même après plusieurs heures de coulée.After the strip has been discarded, it is replaced under the same operating conditions as above, that is to say a casting speed of 1.3 m / min and a lubricant flow rate of 10 1 / hour and it is controlled by the using the microcomputer according to the invention, the speed of the machine and the lubricant inlet valves at the indications of the filter signal. After 15 minutes When running, a frequency of variation of the torque measurement close to 3 hertz is detected. The lubricant flow is then automatically increased to 11 1 / hour and the casting speed reduced by 0.05 m / min. After a few seconds, the frequency of the variations returned to normal and the filtered signal zero. After five minutes of walking under these conditions, the speed is gradually increased to 1.4 m / min and the casting is continued at this speed without the appearance of new micro-bonding even after several hours of casting.
Le procédé selon l'invention trouve son application dans la coulée continue des métaux entre cylindres dans tous les cas où on veut éviter le collage de la bande sur les cylindres et maintenir la marche de la machine dans des conditions de productivité maximum.The method according to the invention finds its application in the continuous casting of metals between cylinders in all cases where it is desired to avoid sticking of the strip on the cylinders and to keep the machine running under conditions of maximum productivity.
Claims (11)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| AT82420009T ATE10591T1 (en) | 1981-01-19 | 1982-01-18 | CONTROL AND ADJUSTMENT PROCEDURES DURING CONTINUOUS CASTING OF STRIPS BETWEEN ROLLS TO PREVENT STICKING. |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FR8101185A FR2498099A2 (en) | 1981-01-19 | 1981-01-19 | METHOD FOR CONTROLLING AND REGULATING MARKET PARAMETERS OF A CONTINUOUS CASTING MACHINE OF BANDS BETWEEN CYLINDERS FOR AVOIDING COLLAGE |
| FR8101185 | 1981-01-19 |
Publications (3)
| Publication Number | Publication Date |
|---|---|
| EP0056777A2 true EP0056777A2 (en) | 1982-07-28 |
| EP0056777A3 EP0056777A3 (en) | 1982-08-18 |
| EP0056777B1 EP0056777B1 (en) | 1984-12-05 |
Family
ID=9254415
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP82420009A Expired EP0056777B1 (en) | 1981-01-19 | 1982-01-18 | Control and regulatory process for continuously casting belts between rolls in order to avoid sticking |
Country Status (22)
| Country | Link |
|---|---|
| US (1) | US4501315A (en) |
| EP (1) | EP0056777B1 (en) |
| JP (1) | JPS57165165A (en) |
| KR (1) | KR880002370B1 (en) |
| AT (1) | ATE10591T1 (en) |
| AU (1) | AU546276B2 (en) |
| BG (1) | BG45551A3 (en) |
| BR (1) | BR8200252A (en) |
| CA (1) | CA1185069A (en) |
| DD (1) | DD201982A5 (en) |
| EG (1) | EG15213A (en) |
| ES (1) | ES8305233A2 (en) |
| FR (1) | FR2498099A2 (en) |
| GB (1) | GB2091455B (en) |
| GR (1) | GR81337B (en) |
| HU (1) | HU183802B (en) |
| IN (1) | IN157291B (en) |
| MX (1) | MX157804A (en) |
| MY (1) | MY8500859A (en) |
| NO (1) | NO157728C (en) |
| SU (1) | SU1138008A3 (en) |
| YU (1) | YU10282A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0407978A2 (en) * | 1989-07-14 | 1991-01-16 | Hunter Engineering Company, Inc. | Roll casting machine crown control |
| WO1992002320A1 (en) * | 1990-08-03 | 1992-02-20 | Davy Mckee (Poole) Limited | Twin roll casting |
| WO1992002321A1 (en) * | 1990-08-03 | 1992-02-20 | Davy Mckee (Poole) Limited | Twin roll casting |
| EP0504075A1 (en) * | 1991-03-12 | 1992-09-16 | Pechiney Rhenalu | Method for preventing sticking on a twin roll caster |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4727927A (en) * | 1987-01-20 | 1988-03-01 | Hunter Engineering Company, Inc. | Casting machine control |
| FR2621839B1 (en) * | 1987-10-14 | 1992-02-21 | Cegedur | METHOD FOR CONTROLLING AND ADJUSTING THE LUBRICATION OF THE WORKING FACE OF ROTARY CYLINDERS OF A CONTINUOUS BELT CASTING MACHINE |
| US5638893A (en) * | 1993-10-07 | 1997-06-17 | Fata Hunter, Inc. | Parting agent spray system |
| JPH0852519A (en) * | 1994-08-11 | 1996-02-27 | Nippon Atsuen Kogyo Kk | Production of aluminum punched sheet |
| CN109715316B (en) | 2016-08-10 | 2021-09-21 | 纽科尔公司 | Thin strip casting method |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR1329801A (en) * | 1961-05-26 | 1963-06-14 | Davy & United Eng Co Ltd | Rolling Mill Control Method and System |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2824346A (en) * | 1955-01-28 | 1958-02-25 | Ohio Crankshaft Co | Method of controlling lubrication of continuous casting |
| US3478808A (en) * | 1964-10-08 | 1969-11-18 | Bunker Ramo | Method of continuously casting steel |
| DE2743579A1 (en) * | 1976-10-05 | 1978-04-06 | Centre Rech Metallurgique | METAL CONTROL METHOD FOR CONTINUOUS CASTING |
| BE869726A (en) * | 1978-08-11 | 1978-12-01 | Centre Rech Metallurgique | METHOD OF REGULATING THE ADDITION OF COVERING POWDER IN CONTINUOUS CASTING OF METALS |
| FR2490516A1 (en) * | 1980-09-01 | 1982-03-26 | Scal Gp Condit Aluminium | METHOD FOR MONITORING AND REGULATING MARKET PARAMETERS OF A CONTINUOUS CASTING MACHINE OF BANDS BETWEEN CYLINDERS |
-
1981
- 1981-01-19 FR FR8101185A patent/FR2498099A2/en active Granted
- 1981-12-29 IN IN1473/CAL/81A patent/IN157291B/en unknown
-
1982
- 1982-01-13 BG BG8254973A patent/BG45551A3/xx unknown
- 1982-01-15 GR GR67017A patent/GR81337B/el unknown
- 1982-01-15 GB GB8201119A patent/GB2091455B/en not_active Expired
- 1982-01-16 EG EG17/82A patent/EG15213A/en active
- 1982-01-18 AU AU79585/82A patent/AU546276B2/en not_active Ceased
- 1982-01-18 NO NO820138A patent/NO157728C/en unknown
- 1982-01-18 SU SU823375306A patent/SU1138008A3/en active
- 1982-01-18 YU YU00102/82A patent/YU10282A/en unknown
- 1982-01-18 US US06/339,846 patent/US4501315A/en not_active Expired - Fee Related
- 1982-01-18 CA CA000394401A patent/CA1185069A/en not_active Expired
- 1982-01-18 EP EP82420009A patent/EP0056777B1/en not_active Expired
- 1982-01-18 ES ES508822A patent/ES8305233A2/en not_active Expired
- 1982-01-18 BR BR8200252A patent/BR8200252A/en unknown
- 1982-01-18 JP JP57005856A patent/JPS57165165A/en active Granted
- 1982-01-18 MX MX191017A patent/MX157804A/en unknown
- 1982-01-18 AT AT82420009T patent/ATE10591T1/en active
- 1982-01-19 DD DD82236852A patent/DD201982A5/en not_active IP Right Cessation
- 1982-01-19 KR KR8200207A patent/KR880002370B1/en not_active IP Right Cessation
- 1982-01-19 HU HU82141A patent/HU183802B/en not_active IP Right Cessation
-
1985
- 1985-12-30 MY MY859/85A patent/MY8500859A/en unknown
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR1329801A (en) * | 1961-05-26 | 1963-06-14 | Davy & United Eng Co Ltd | Rolling Mill Control Method and System |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0407978A2 (en) * | 1989-07-14 | 1991-01-16 | Hunter Engineering Company, Inc. | Roll casting machine crown control |
| EP0407978A3 (en) * | 1989-07-14 | 1993-05-19 | Hunter Engineering Company, Inc. | Roll casting machine crown control |
| WO1992002320A1 (en) * | 1990-08-03 | 1992-02-20 | Davy Mckee (Poole) Limited | Twin roll casting |
| WO1992002321A1 (en) * | 1990-08-03 | 1992-02-20 | Davy Mckee (Poole) Limited | Twin roll casting |
| EP0504075A1 (en) * | 1991-03-12 | 1992-09-16 | Pechiney Rhenalu | Method for preventing sticking on a twin roll caster |
| FR2673865A1 (en) * | 1991-03-12 | 1992-09-18 | Rhenalu Pechiney | METHOD FOR AVOIDING SCALING ON A COUPLING MACHINE BETWEEN CYLINDERS. |
| US5224535A (en) * | 1991-03-12 | 1993-07-06 | Pechiney Rhenalu | Method of avoiding run out on a machine for casting between rolls |
Also Published As
| Publication number | Publication date |
|---|---|
| EP0056777A3 (en) | 1982-08-18 |
| US4501315A (en) | 1985-02-26 |
| NO157728B (en) | 1988-02-01 |
| KR830008770A (en) | 1983-12-14 |
| YU10282A (en) | 1986-04-30 |
| IN157291B (en) | 1986-02-22 |
| NO820138L (en) | 1982-07-20 |
| ES508822A0 (en) | 1983-04-01 |
| GR81337B (en) | 1984-12-11 |
| ATE10591T1 (en) | 1984-12-15 |
| AU7958582A (en) | 1982-07-29 |
| EG15213A (en) | 1991-06-30 |
| MX157804A (en) | 1988-12-15 |
| ES8305233A2 (en) | 1983-04-01 |
| MY8500859A (en) | 1985-12-31 |
| NO157728C (en) | 1988-05-11 |
| KR880002370B1 (en) | 1988-11-03 |
| GB2091455B (en) | 1984-05-10 |
| FR2498099A2 (en) | 1982-07-23 |
| JPS6238071B2 (en) | 1987-08-15 |
| AU546276B2 (en) | 1985-08-22 |
| BR8200252A (en) | 1982-11-23 |
| GB2091455A (en) | 1982-07-28 |
| SU1138008A3 (en) | 1985-01-30 |
| HU183802B (en) | 1984-06-28 |
| FR2498099B2 (en) | 1983-02-18 |
| DD201982A5 (en) | 1983-08-24 |
| JPS57165165A (en) | 1982-10-12 |
| BG45551A3 (en) | 1989-06-15 |
| EP0056777B1 (en) | 1984-12-05 |
| CA1185069A (en) | 1985-04-09 |
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