EP0000855B1 - Pre-controlling process of a continuous tandem train for the hot-rolling of metals - Google Patents

Pre-controlling process of a continuous tandem train for the hot-rolling of metals Download PDF

Info

Publication number
EP0000855B1
EP0000855B1 EP19780400073 EP78400073A EP0000855B1 EP 0000855 B1 EP0000855 B1 EP 0000855B1 EP 19780400073 EP19780400073 EP 19780400073 EP 78400073 A EP78400073 A EP 78400073A EP 0000855 B1 EP0000855 B1 EP 0000855B1
Authority
EP
European Patent Office
Prior art keywords
product
speed
stand
rotational speed
rolling
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
EP19780400073
Other languages
German (de)
French (fr)
Other versions
EP0000855A1 (en
EP0000855B2 (en
Inventor
Philippe Millamon
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Institut de Recherches de la Siderurgie Francaise IRSID
Original Assignee
Institut de Recherches de la Siderurgie Francaise IRSID
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Family has litigation
First worldwide family litigation filed litigation Critical https://patents.darts-ip.com/?family=9194386&utm_source=google_patent&utm_medium=platform_link&utm_campaign=public_patent_search&patent=EP0000855(B1) "Global patent litigation dataset” by Darts-ip is licensed under a Creative Commons Attribution 4.0 International License.
Application filed by Institut de Recherches de la Siderurgie Francaise IRSID filed Critical Institut de Recherches de la Siderurgie Francaise IRSID
Publication of EP0000855A1 publication Critical patent/EP0000855A1/en
Publication of EP0000855B1 publication Critical patent/EP0000855B1/en
Application granted granted Critical
Publication of EP0000855B2 publication Critical patent/EP0000855B2/en
Expired legal-status Critical Current

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B37/00—Control devices or methods specially adapted for metal-rolling mills or the work produced thereby
    • B21B37/48—Tension control; Compression control
    • B21B37/52—Tension control; Compression control by drive motor control
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21B—ROLLING OF METAL
    • B21B37/00—Control devices or methods specially adapted for metal-rolling mills or the work produced thereby
    • B21B37/16—Control of thickness, width, diameter or other transverse dimensions

Definitions

  • the invention relates to the hot rolling of flat or long products, in particular thick products, in rolling mills with tandem cages and, more specifically, the presetting of the cages before engagement of the product.
  • tandem cages which has long been established for finishing trains, is beginning to gain importance for the hot rolling of thick products. It allows, in fact, a significant saving on the dimensioning of the halls and the length of the transport tables, a gain in heating by reduction of the cooling times and a shorter rolling time, therefore better productivity.
  • the problems encountered are much more complex, due to the large thicknesses and low mechanical characteristics, than for cold rolling or even hot rolling of thin products.
  • control, within relatively narrow limits, of the tension (traction or compression) between the cages is essential if one wishes to avoid, on too many blanks, geometry or surface defects.
  • a tension can, of course, appear at any time during the rolling of the product, the characteristics of which are not always strictly constant, but the greatest risk of appearance lies at the time of engagement of the debouche, already in engagement in one cage, in the next. It is, of course, possible to take the necessary measures as soon as voltage is detected, but it is clearly preferable to act before the product even reaches the downstream cage by presetting the latter, that is to say by giving it a speed compatible with that of the product leaving the upstream cage.
  • a method of presetting has already been proposed before engagement of the product in the corresponding cage consisting in calculating the expected thickness reductions and, by equalizing the flow rates, in deducing therefrom the speeds of the product and of the cylinders. But this method can only give a very rough approximation: the thicknesses obtained in practice are rarely those calculated. There is therefore a risk of seeing looping appear if the calculated flow is insufficient, or even more dangerous pulling because, except for very high values, it does not result in a phenomenon visible to the operator during rolling.
  • the object of the present invention is precisely, in the case where there are rolling models using the speed of the product as a reference quantity, to provide a finer pre-setting of the cages.
  • measurements of inlet and outlet thickness of the product and measurements of rolling force are also carried out and the coefficients of the model are corrected more precisely by recalculating them from the value measured from the exit speed of the product from the upstream stand and from the measured values of the thicknesses and the rolling force.
  • the speed of exit of the product from the upstream cage is measured by the so-called correlation method, known per se, which will be recalled below.
  • the method according to the invention can be applied to a rolling mill where the product is engaged in more than two successive stands. A sufficient approximation is then obtained by considering the cages as independent two by two and by presetting them successively.
  • the method according to the invention essentially consists in ensuring the compatibility of the speed ratio of two successive cages with the flow rates of metal having to pass through them even before the product has reached the downstream cage.
  • the only possible preset mode is the use, for a rough draft, of the values obtained for a previous rough draft of similar characteristics, rolled under satisfactory conditions, using for example of the process described in FR-A-2 395 086.
  • recent progress made in the knowledge of deformation phenomena during rolling has made it possible to develop a certain number of models, linking quantities such as input and output speeds and thicknesses, rolling forces and torques, product temperature dimensions and variations, input and output pulls, models which are currently available in the literature.
  • it is necessary to use a model where the reference quantity is the speed in order to be able to recalculate all the coefficients from a simple measurement of product exit speed.
  • the process according to the invention can, of course, be used alone or followed by any tension control process when the product has entered the downstream cage, but it is particularly advantageous to associate it with the tension control process continuously exposed in FR-A-2 395 086.
  • the detectors and the signal processing means which they supply may be common to both methods. It is thus possible to ensure complete control of the tension to which the product is subjected, from its entry into the upstream cage to its exit from the downstream cage, and, consequently, appreciably reducing the number of blanks discarded for . poor geometry due to excessive traction or compression.
  • the product considered is a thick flat product, but it is very clear that the transposition to any long product can be done immediately, by replacing the concept of thickness by that of section.
  • the signals emitted by detectors 4 and 5 are sent to a delay correlator enslaved; to determine the initial value of the delay, the signals supplied by the passage in front of the detectors of the head of the product are used.
  • This device is identical to that recommended in FR-A-2 395 086 and it is moreover advantageous to use a single pair of detectors judiciously placed between each cage to implement the two methods together.
  • the desired thickness reductions are determined and, using the model, the speeds V 2 and V 3 to be imposed on the working rolls of each of the cages are calculated. .
  • the parameter to take into account is the ratio of the speeds of the two cages.
  • FIG. 2 shows the speed of the product 1 as a function of its position relative to the cages 2 and 3 marked on the abscissa axis by the points C 2 and C 3 .
  • the curve a corresponds to the optimal preset which has just been described
  • the curve b on the other hand translates an incorrect preset, with appearance of a traction too strong with the engagement in the cage 3, traction caused by a rotation speed too high from this cage.
  • the presetting method according to the invention can easily be extended to a higher number of cages where the product will be taken simultaneously. Indeed, according to a first generally sufficient approximation, we consider the cages as independent two by two. The first two cages having been preset in the manner described above, the second and the third are then considered in isolation and the latter is preset by the method according to the invention, keeping however constant the speed ratio of the first two cages.
  • the method according to the invention therefore makes it possible to optimally preset the cages of a rolling mill and its association with a method for continuously monitoring the traction between cages is of definite economic interest by significantly reducing the number of products discarded for defects in geometry.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Control Of Metal Rolling (AREA)

Description

L'invention concerne le laminage à chaud de produits plats ou longs notamment de produits épais, dans des laminoirs à cages tandem et, plus spécialement, le préréglage des cages avant engagement du produit.The invention relates to the hot rolling of flat or long products, in particular thick products, in rolling mills with tandem cages and, more specifically, the presetting of the cages before engagement of the product.

L'utilisation des cages tandem, qui s'est imposée depuis longtemps pour les trains finisseurs, commence à prendre de l'importance pour le laminage à chaud des produits épais. Elle permet, en effet, une économie importante sur le dimensionnement des halles et la longueur des tables de transport, un gain en chauffage par diminution des temps de refroidissement et un temps de laminage plus court, donc une meilleure productivité. Cependant, dans ce dernier cas les problèmes rencontrés sont beaucoup plus complexes, du fait des fortes épaisseurs et des faibles caractéristiques mécaniques, que pour le laminage à froid ou même le laminage à chaud des produits minces. En particulier le contrôle, dans des limites relativement étroites, de la tension (traction ou compression) entre les cages est indispensable si l'on veut éviter, sur un trop grand nombre d'ébauches, des défauts de géométrie ou de surface. Une tension peut, bien entendu, apparaître à tout moment du laminage du produit, dont les caractéristiques ne sont pas toujours rigoureusement constantes, mais le plus grand risque d'apparition se situe au moment de l'engagement de l'ébouche, déjà en prise dans une cage, dans la suivante. Il est, bien sûr, possible de prendre les mesures nécessaires dès détection de la tension, mais nettement préférable d'agir avant même que le produit n'atteigne la cage aval en préréglant cette dernière, c'est-à-dire en lui donnant une vitesse compatible avec celle de sortie du produit de la cage amont.The use of tandem cages, which has long been established for finishing trains, is beginning to gain importance for the hot rolling of thick products. It allows, in fact, a significant saving on the dimensioning of the halls and the length of the transport tables, a gain in heating by reduction of the cooling times and a shorter rolling time, therefore better productivity. However, in the latter case the problems encountered are much more complex, due to the large thicknesses and low mechanical characteristics, than for cold rolling or even hot rolling of thin products. In particular, control, within relatively narrow limits, of the tension (traction or compression) between the cages is essential if one wishes to avoid, on too many blanks, geometry or surface defects. A tension can, of course, appear at any time during the rolling of the product, the characteristics of which are not always strictly constant, but the greatest risk of appearance lies at the time of engagement of the debouche, already in engagement in one cage, in the next. It is, of course, possible to take the necessary measures as soon as voltage is detected, but it is clearly preferable to act before the product even reaches the downstream cage by presetting the latter, that is to say by giving it a speed compatible with that of the product leaving the upstream cage.

Pour des profilés, les variations de forme, par rapport à celle imposée par les cages de laminage, de la tête et de la queue du produit, se traduisent par des variations de traction au moment de leur passage. On a déjà proposé FR-A-1 505 873 pour les têtes et US-A-4 003 229 pour les queues) d'agir sur les vitesses de rotation des cylindres d'une cage lors de l'engagement de la tête ou avant entrée de la queue dans cette cage. Mais ces procédés concernent des problèmes particuliers liés à la forme du produit et ne sont pas d'application générale.For profiles, the variations in shape, compared to that imposed by the rolling stands, of the head and the tail of the product, result in variations in tension when they pass. It has already been proposed FR-A-1 505 873 for the heads and US-A-4 003 229 for the tails) to act on the rotation speeds of the cylinders of a cage during the engagement of the head or before tail entering this cage. However, these methods relate to particular problems linked to the shape of the product and are not of general application.

D'autre part, dans le cas de bandes, on a proposé, pour éviter des tractions ou des bouclages nuisibles, de régler la distance inter- cylindres, sans agir sur les vitesses de rotation des cages.On the other hand, in the case of bands, it has been proposed, in order to avoid harmful pulls or loops, to adjust the inter-cylinder distance, without acting on the speeds of rotation of the cages.

On sait également, d'après les enseignements des brevets FR-A-2 323 463 et FR-A-1 514 209, régler, en cours de laminage, la traction appliqiuée au produit, en évaluent cette dernière indirectement par des' mesures d'effort de laminage ou de couple moteur et en agissant sur les vitesses des cylindres pour ramener la valeur prise par le paramètre de réglage choisi à une valeur prédéterminée.We also know, from the teachings of patents FR-A-2 323 463 and FR-A-1 514 209, regulate, during rolling, the traction applied to the product, evaluate the latter indirectly by 'measurements 'rolling force or engine torque and by acting on the cylinder speeds to reduce the value taken by the chosen adjustment parameter to a predetermined value.

On a déjà proposé une méthode de préréglage avant engagement du produit dans la cage correspondante consistant à calculer les réductions d'épaisseur prévues et, en égalant les débits, à en déduire les vitesses du produit et des cylindres. Mais cette méthode ne peut donner qu'une approximation très grossière: les épaisseurs obtenues en pratique sont rarement celles calculées. On risque donc de voir apparaître des bouclages si le débit calculé est insuffisant, ou une traction encore plus dangereuse car, sauf pour des valeurs très élevées, elle ne se traduit pas par un phénomène visible pour l'opérateur pendant le laminage.A method of presetting has already been proposed before engagement of the product in the corresponding cage consisting in calculating the expected thickness reductions and, by equalizing the flow rates, in deducing therefrom the speeds of the product and of the cylinders. But this method can only give a very rough approximation: the thicknesses obtained in practice are rarely those calculated. There is therefore a risk of seeing looping appear if the calculated flow is insufficient, or even more dangerous pulling because, except for very high values, it does not result in a phenomenon visible to the operator during rolling.

Dans sa FR-A-2 395 086, publiée après la date de priorité de la présente demande, le demandeur a exposé un procédé permettant de déterminer en continu et de maintenir à une valeur optimale la tension entre les cages. Ce procédé consiste à mesurer en continu les vitesses du produit et des cylindres, à calculer le glissement correspondant, à le comparer à une valeur de consigne et à modifier éventuellement les vitesses de l'une ou des deux cages de manière à annuler la différence entre la valeur calculée et la valeur de consigne. Les valeurs des vitesses qui, pour une ébauche, conduisent à des conditions de laminage sous tension faible, peuvent alors être utilisées comme valeurs de préréglage pour l'ébauche suivant. Les résultats obtenus sont bien meilleurs que ceux provenant d'un simple calcul de débits et, souvent, peuvent être considérés comme satisfaisants. Cependant, deux ébauches successives ont rarement des caractéristiques indentiques et il faut généralement effectuer de légères corrections de vitesse lors de l'engagement du produit dans la cage aval.In its FR-A-2 395 086, published after the priority date of the present application, the applicant has exposed a process making it possible to continuously determine and maintain the tension between the cages at an optimal value. This process consists of continuously measuring the speeds of the product and the cylinders, calculating the corresponding slip, comparing it to a set value and possibly modifying the speeds of one or both cages so as to cancel the difference between the calculated value and the set value. The values of the speeds which, for a roughing, lead to rolling conditions under low tension, can then be used as preset values for the following roughing. The results obtained are much better than those resulting from a simple calculation of flow rates and, often, can be considered satisfactory. However, two successive drafts rarely have identical characteristics and it is generally necessary to make slight speed corrections when engaging the product in the downstream cage.

Le but de la présente invention est précisément, dans le cas où l'on dispose de modèles de laminage utilisant comme grandeur de référence la vitesse du produit, de fournir un préréglage plus fin des cages.The object of the present invention is precisely, in the case where there are rolling models using the speed of the product as a reference quantity, to provide a finer pre-setting of the cages.

A cet effet l'invention a pour objet un procédé de préréglage des cages d'un train continu à cages tandem pour le laminage à chaud de produits métalliques, notamment de produits épais, à l'aide d'un modèle donnant les relations entre les valeurs de certains paramètres tels que les vitesses d'entrée et de sortie, les dimensions et les variations de température du produit, les forces et couples de laminage, le glissement, les tractions d'entrée et de sortie, la grandeur de référence étant la vitesse, procédé selon lequel on agit sur la vitesse de rotation des cylindres et caractérisé en ce que:

  • - les réductions d'épaisseur par cage étant choisies, on calcule, à l'aide du modèle, le rapport des vitesses de rotation des cages amont et aval et la vitesse de sortie du produit de la cage amont;
  • - on mesure la vitesse de sortie du produit de la cage amont, ce dernier étant en prise dans cette seule cage;
  • - on compare la vitesse mesurée avec la vitesse calculée;
  • - on corrige, si nécessaire, les coefficients affectant les différents paramètres des relations fournies par le molèle en les recalculant à partir de la valeur mesurée de la vitesse du produit;
  • - on calcule, à l'aide des coefficients corrigés du modèle le nouveau rapport des vitesses de rotation des cylindres des deux cages.
  • - on modifie la vitesse de rotation d'au moins une des cages selon le nouveau rapport avant entrée du produit dans la cage aval.
To this end, the subject of the invention is a method for presetting the cages of a continuous train with tandem cages for the hot rolling of metal products, in particular thick products, using a model giving the relationships between the values of certain parameters such as input and output speeds, dimensions and product temperature variations, rolling forces and torques, slip, input and output pulls, the reference quantity being the speed, process by which one acts on the cylinder rotation speed and characterized in that:
  • - the thickness reductions per cage being chosen, the ratio of the speeds of rotation of the upstream and downstream cages and the speed of product output from the upstream cage are calculated using the model;
  • - Measuring the product exit speed from the upstream cage, the latter being engaged in this single cage;
  • - the measured speed is compared with the calculated speed;
  • - Correct, if necessary, the coefficients affecting the different parameters of the relationships provided by the molle by recalculating them from the measured value of the speed of the product;
  • - using the corrected coefficients of the model, the new ratio of the rotational speeds of the cylinders of the two cages is calculated.
  • - The rotation speed of at least one of the cages is modified according to the new ratio before the product enters the downstream cage.

On peut corriger soit la vitesse de rotation de la cage amont, soit celle de la cage aval, l'autre vitesse de rotation étant maintenue constante, en imposant la valeur calculée à partir du nouveau rapport des vitesses de rotation des cylindres des deux cages.One can correct either the speed of rotation of the upstream cage, or that of the downstream cage, the other speed of rotation being kept constant, by imposing the value calculated from the new ratio of the speeds of rotation of the cylinders of the two cages.

Selon un mode de réalisation particulièrement avantageux, on effectue également des mesures d'épaisseur d'entrée et de sortie du produit et des mesures de force de laminage et on corrige de manière plus fine les coefficients du modèle en les recalculant à partir de la valeur mesurée de la vitesse de sortie du produit de la cage amont et des valeurs mesurées des épaisseurs et de la force de laminage.According to a particularly advantageous embodiment, measurements of inlet and outlet thickness of the product and measurements of rolling force are also carried out and the coefficients of the model are corrected more precisely by recalculating them from the value measured from the exit speed of the product from the upstream stand and from the measured values of the thicknesses and the rolling force.

Selon une variante de mise en oeuvre de l'invention, la vitesse de sortie du produit de la cage amont est mesurée par la méthode dite de correlation, connue en soi, qui sera rappelée par la suite.According to a variant implementation of the invention, the speed of exit of the product from the upstream cage is measured by the so-called correlation method, known per se, which will be recalled below.

Le procédé selon l'invention peut être appliqué à un laminoir où le produit est en prise dans plus de deux cages successives. On obtient alors une approximation suffisante en considérant les cages comme indépendantes deux à deux et en les préréglant successivement.The method according to the invention can be applied to a rolling mill where the product is engaged in more than two successive stands. A sufficient approximation is then obtained by considering the cages as independent two by two and by presetting them successively.

Comme on le comprend, le procédé selon l'invention consiste essentiellement à assurer la compatibilité du rapport des vitesses de deux cages successives avec les débits de métal devant les traverser avant même que le produit n'ait atteint la cage aval. Lorsqu'on n'emploie pas de modèle pour effectuer le laminage, le seul mode de préréglage possible est l'utilisation, pour une ébauche, des valeurs obtenues pour une ébauche précédente de caractéristiques voisines, laminée dans des conditions satisfaisantes, à l'aide par exemple de procédé exposé dans la FR-A-2 395 086. Cependant, les progrès récents effectués dans la connaissance des phénomènes de déformation au cours du laminage ont permis de mettre au point un certain nombre de modèles, reliant des grandeurs telles que les vitesses et les épaisseurs d'entrée et de sortie, les forces et couples de laminage, les dimensions et les variations de température du produit, les tractions d'entrée et de sortie, modèles qui sont actuellement disponibles dans la littérature. Afin de mettre en oeuvre le procédé selon l'invention, il est nécessaire d'utiliser un modèle où la grandeur de référence est la vitesse, afin de pouvoir recalculer tous les coefficients à partir d'une simple mesure de vitesse de sortie du produit.As will be understood, the method according to the invention essentially consists in ensuring the compatibility of the speed ratio of two successive cages with the flow rates of metal having to pass through them even before the product has reached the downstream cage. When a model is not used for rolling, the only possible preset mode is the use, for a rough draft, of the values obtained for a previous rough draft of similar characteristics, rolled under satisfactory conditions, using for example of the process described in FR-A-2 395 086. However, recent progress made in the knowledge of deformation phenomena during rolling has made it possible to develop a certain number of models, linking quantities such as input and output speeds and thicknesses, rolling forces and torques, product temperature dimensions and variations, input and output pulls, models which are currently available in the literature. In order to implement the method according to the invention, it is necessary to use a model where the reference quantity is the speed, in order to be able to recalculate all the coefficients from a simple measurement of product exit speed.

Le procédé selon l'invention peut, bien entendu, être employé seul ou suivi d'un procédé de contrôle de tension quelconque lorsque le produit est entré dans la cage aval, mais il est particulièrement avantageux de l'associer au procédé de contrôle de tension en continu exposé dans la FR-A-2 395 086. Lorsque, notamment, les mesures de vitesse sont effectuées par la méthode de corrélation, les détecteurs et les moyens de traitement des signaux qu'ils fournissent peuvent être communs aux deux procédés. On peut ainsi assurer un contrôle complet de la tension à laquelle est soumis le produit, depuis son entrée dans la cage amont jusqu'à sa sortie de la cage aval, et, par conséquent, réduire de façon appréciable le nombre d'ébauche rebutées pour. une mauvaise géométrie due à une traction ou une compression excessive.The process according to the invention can, of course, be used alone or followed by any tension control process when the product has entered the downstream cage, but it is particularly advantageous to associate it with the tension control process continuously exposed in FR-A-2 395 086. When, in particular, the speed measurements are carried out by the correlation method, the detectors and the signal processing means which they supply may be common to both methods. It is thus possible to ensure complete control of the tension to which the product is subjected, from its entry into the upstream cage to its exit from the downstream cage, and, consequently, appreciably reducing the number of blanks discarded for . poor geometry due to excessive traction or compression.

L'invention sera de toutes façons bien comprise en se reportant à la description qui va suivre, donnée à titre d'exemple, purement illustratif, en référence à la planche de dessin annexée sur laquelle:

  • - la figure 1 schématise deux cages consécutives d'un train dégrossisseur
  • -la figure 2 représente la vitesse du produit entre les deux cages en fonction de sa position par rapport à celles-ci.
The invention will in any case be well understood by referring to the description which follows, given by way of example, purely illustrative, with reference to the attached drawing board on which:
  • - Figure 1 shows schematically two consecutive cages of a roughing train
  • FIG. 2 represents the speed of the product between the two cages as a function of its position relative to them.

Le produit considéré est un produit plat épais, mais il est bien clair que la transposition à tout produit long peut se faire de façon immédiate, en remplaçant la notion d'épaisseur par celle de section.The product considered is a thick flat product, but it is very clear that the transposition to any long product can be done immediately, by replacing the concept of thickness by that of section.

Sur la figure 1 on peut voir en 1 le produit, en prise dans la cage 2 et se dirigeant vers la cage 3. Les deux cages ont été schématisées par leurs cylindres de travail. L'ébauche sort de la cage 2 avec la vitesse VS, mesurée par tout moyen suffisamment précis, mais de préférence à l'aide du procédé et du dispositif décrits dans le FR-A-2.161.757. Cette méthode consiste à calculer la vitesse par détection et corrélation de deux signaux aléatoires semblables, décalés dans le temps et liés au produit en déplacement. Deux détecteurs optiques 4 et 5, des récepteurs photoélectriques par exemple, sont placés entre les cages, au-dessus du produit, et sont disposés à une distance bien définie l'un de l'autre par rapport au sens de défilement du produit. Les signaux émis par les détecteurs 4 et 5 sont envoyés dans un corrélateur à retard asservi; pour déterminer la valeur initiale du retard on utilise les signaux fournis par le passage devant les détecteurs de la tête du produit. Ce dispositif est identique à celui préconisé dans la FR-A-2 395 086 et il est d'ailleurs avantageux d'employer une seule paire de détecteurs judicieusement placée entre chaque cage pour mettre en oeuvre les deux procédés ensemble.In Figure 1 we can see in 1 the product, engaged in the cage 2 and moving towards the cage 3. The two cages have been shown schematically by their working cylinders. The blank leaves the cage 2 with the speed V S , measured by any sufficiently precise means, but preferably using the method and the device described in FR-A-2,161,757. This method consists in calculating the speed by detection and correlation of two similar random signals, shifted in time and linked to the moving product. Two optical detectors 4 and 5, photoelectric receivers for example, are placed between the cages, above the product, and are arranged at a well-defined distance from each other relative to the direction of travel of the product. The signals emitted by detectors 4 and 5 are sent to a delay correlator enslaved; to determine the initial value of the delay, the signals supplied by the passage in front of the detectors of the head of the product are used. This device is identical to that recommended in FR-A-2 395 086 and it is moreover advantageous to use a single pair of detectors judiciously placed between each cage to implement the two methods together.

On détermine, avant même que le produit ne soit engagé dans la cage 2, les réductions d'épaisseur désirées et, à l'aide du modèle, on calcule les vitesses V2 et V3 à imposer aux cylindres de travail de chacune des cages. En fait, pour obtenir le même résultat plusieurs réglages sont possibles car le paramètre à prendre en compte est le rapport des vitesses des deux cages. Une fois ce premier préréglage effectué le produit entre dans la cage 2 dont il ressort généralement avec une vitesse Vs différente de la vitesse Vg prévue par le modèle. A partir de cette valeur on calcule les nouveaux coefficients du modèle et le nouveau rapport des vitesses à donner aux cages. On effectue alors le préréglage final en imposant à la cage 3 la nouvelle vitesse calculée. On pourrait aussi modifier la vitesse de la cage 2 seule ou les vitesses des deux cages, mais il est plus simple d'agir seulement sur la cage 3. Afin d'adapter plus complètement le' modèle aux caractéristiques réelles du produit laminé, on peut prévoir d'équiper la train de jauges d'épaisseur (par exemple des jauges à rayons y) et de dispositifs de mesure de la force de laminage, tels que des pressducteurs, ou de ces derniers seulement qui permettent d'estimer les épaisseurs avec une approximation suffisante.Before the product is engaged in cage 2, the desired thickness reductions are determined and, using the model, the speeds V 2 and V 3 to be imposed on the working rolls of each of the cages are calculated. . In fact, to obtain the same result several adjustments are possible because the parameter to take into account is the ratio of the speeds of the two cages. Once this first preset has been carried out, the product enters the cage 2 from which it generally emerges with a speed V s different from the speed Vg provided by the model. From this value we calculate the new coefficients of the model and the new speed ratio to be given to the cages. The final presetting is then carried out by imposing on cage 3 the new calculated speed. One could also modify the speed of the cage 2 alone or the speeds of the two cages, but it is simpler to act only on the cage 3. In order to adapt the model more completely to the real characteristics of the rolled product, one can plan to equip the train with thickness gauges (for example y-ray gauges) and with devices for measuring the rolling force, such as pressure reducers, or only of these which allow thicknesses to be estimated with a sufficient approximation.

Sur la figure 2 on a représenté la vitesse du produit 1 en fonction de sa position par rapport aux cages 2 et 3 repérées sur l'axe des abscisses par les points C2 et C3. Lorsque le produit est en prise dans la cage 2 seulement, sa vitesse de sortie est VS; à rengagement dans la cage 3, si cette dernière à été correctement préréglée, la vitesse du produit doit augmenter légèrement car il est préférable de laminer sous traction légère, ainsi que le demandeur l'a exposé dans la FR-A- 2 395 086. Enfin à la sortie de la cage 2 le produit n'est en prise que dans la cage aval et sa vitesse augmente à nouveau. La courbe a correspond au préréglage optimal qui vient d'être décrit, la courbe b, par contre traduit un préréglage incorrect, avec apparition d'une traction trop forte à l'engagement dans la cage 3, traction causée par une vitesse de rotation trop élevée de cette cage. Le procédé de préréglage selon l'invention peut être facilement étendu à un nombre plus élevé de cages où le produit sera en prise simultanément. En effet, selon une première approximation généralement suffisante, on considère les cages comme indépendantes deux à deux. Les deux premières cages ayant été préréglées de la manière exposée plus haut, on considère ensuite la seconde et la troisième isolément et on prérègle cette dernière par le procédé selon l'invention, en gardant toutefois constant le rapport des vitesses des deux premières cages. Cependant, si le modèle de laminage est suffisamment élaboré, on peut tenir compte plus rigoureusement du fait que la variation de vitesse entre les deux dernières cages est en partie imputable à la traction qui s'établit entre les deux premières au moment de l'engagement dans la troisième. De proche en proche on peut donc ainsi prérégler un nombre quelconque de cages.FIG. 2 shows the speed of the product 1 as a function of its position relative to the cages 2 and 3 marked on the abscissa axis by the points C 2 and C 3 . When the product is engaged in cage 2 only, its exit speed is V S ; upon re-engagement in the cage 3, if the latter has been correctly preset, the speed of the product must increase slightly because it is preferable to laminate under light traction, as the applicant has explained in FR-A-2 395 086. Finally at the outlet of the cage 2 the product is only engaged in the downstream cage and its speed increases again. The curve a corresponds to the optimal preset which has just been described, the curve b, on the other hand translates an incorrect preset, with appearance of a traction too strong with the engagement in the cage 3, traction caused by a rotation speed too high from this cage. The presetting method according to the invention can easily be extended to a higher number of cages where the product will be taken simultaneously. Indeed, according to a first generally sufficient approximation, we consider the cages as independent two by two. The first two cages having been preset in the manner described above, the second and the third are then considered in isolation and the latter is preset by the method according to the invention, keeping however constant the speed ratio of the first two cages. However, if the rolling model is sufficiently developed, it can be taken into account more rigorously that the speed variation between the last two stands is partly due to the traction which is established between the first two at the time of engagement. in the third. Gradually, we can therefore preset any number of cages.

Le procédé selon l'invention permet donc de prérégler de façon optimale les cages d'un laminoir et son association à un procédé de contrôle en continu de la traction entre cages présente un intérêt économique certain en diminuant sensiblement le nombre de produits rebutés pour défauts de géométrie.The method according to the invention therefore makes it possible to optimally preset the cages of a rolling mill and its association with a method for continuously monitoring the traction between cages is of definite economic interest by significantly reducing the number of products discarded for defects in geometry.

Claims (5)

1. A method for the preliminary adjustment of a tandem stand continuous mill for the hot rolling of metal products, in particular thick products, by means of a model giving the ratios between the values of certain parameters such as input and output speeds, the dimensions and the temperature variations of the product, the rolling forces and torques, the slip, the input and output tractions, the reference value being the' speed, and in which method the rotational speed of the rolls is acted upon characterised in that:
-the thickness reductions per stand having been selected, the rotational speed ratio of the upstream and downstream stands and the output speed of the product from the upstream stand are calculated by means of the model;
-the output speed of the product from the upstream stand is measured, the product being engaged in this stand alone;
-the measured speed is compared with the calculated speed;
-the coefficients relating to the various parameters of the ratios provided by the model are corrected, if necessary, by re-calculating them from the measured value of the speed of the product;
- the new rotational speed ratio of the rolls of the two stands is calculated from the corrected coefficients of the model;
-the rotational speed of at least one of the stands is modified in according with the new ratio before the entry of the product into the downstream stand.
2. A method as claimed in claim 1, characterised in that new rotational speed of the downstream stand is calculated from the new rotational speed ratio of the rolls of the two stands, the rotational speed of the upstream stand being maintained constant.
3. A method as claimed in claim 1, characterised in that new rotational speed of the upstream stand is calculated from the new rotational speed ratio of the rolls of the two stands, the rotational speed of the upstream stand being maintained constant.
4. A method as claimed in one of claims 1 to 3, characterised in that measurements of the input and output thickness of the product and measurements of the rolling force are carried out, and in that the coefficients of the model are modified by re-calculating them from the measured value of the output speed of the product from the upstream stand and the measured values of the thicknesses and the rolling force.
5. A method as claimed in one of claims 1 to 4, characterised in that the output speed of the product from the upstream stand is measured by the detection and correlation of two similar random signals offset in time and related to the product, the correlation being carried out by a servo-controlled delay correlator, the initial value of the said delay corresponding to the average speed of passage of the head of the product in front of the detectors.
EP19780400073 1977-08-08 1978-08-04 Pre-controlling process of a continuous tandem train for the hot-rolling of metals Expired EP0000855B2 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR7724457 1977-08-08
FR7724457A FR2399883A1 (en) 1977-08-08 1977-08-08 PROCESS FOR PRESETTING A CONTINUOUS TRAIN WITH TANDEM CAGES FOR HOT ROLLED METAL PRODUCTS

Publications (3)

Publication Number Publication Date
EP0000855A1 EP0000855A1 (en) 1979-02-21
EP0000855B1 true EP0000855B1 (en) 1981-01-28
EP0000855B2 EP0000855B2 (en) 1987-04-29

Family

ID=9194386

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19780400073 Expired EP0000855B2 (en) 1977-08-08 1978-08-04 Pre-controlling process of a continuous tandem train for the hot-rolling of metals

Country Status (3)

Country Link
EP (1) EP0000855B2 (en)
DE (1) DE2860375D1 (en)
FR (1) FR2399883A1 (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0004598A2 (en) * 1978-04-10 1979-10-17 BROWN, BOVERI & CIE Aktiengesellschaft Mannheim Process and circuit for interstand tension control in a continuous rolling mill having individual drives
EP0439663A1 (en) * 1990-02-02 1991-08-07 Siemens Aktiengesellschaft Method of controlling a continuous multistand rolling mill
EP0455381A1 (en) * 1990-05-01 1991-11-06 Allegheny Ludlum Corporation Method for controlling tension in a metal rolling mill
AU636545B1 (en) * 1992-01-28 1993-04-29 Kabushiki Kaisha Toshiba System for controlling strip thickness in rolling mills

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102004022334A1 (en) * 2004-05-06 2005-12-01 Siemens Ag Process for rolling a rolling stock with transition area
FR3067026A1 (en) 2017-05-31 2018-12-07 Lionel Gerard Vandenbulcke CORROSION RESISTANT CERAMIC MATRIX COMPOSITE AND METHOD FOR MANUFACTURING THE SAME

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1427926C3 (en) * 1965-12-22 1975-05-22 Kloeckner-Werke Ag, 4100 Duisburg Speed control for the rolls of a rolling stand
GB1163274A (en) * 1965-12-28 1969-09-04 British Iron Steel Research Improvements in and relating to Rolling Mills
BE790341A (en) * 1971-10-29 1973-04-20 Siderurgie Fse Inst Rech
US3762194A (en) * 1972-06-28 1973-10-02 Gen Electric Constant speed driven continuous rolling mill
JPS5147146B2 (en) * 1972-09-06 1976-12-13
DE2541071C3 (en) * 1975-09-15 1984-07-12 Siemens AG, 1000 Berlin und 8000 München Device for regulating the tensile force transmitted in the rolling stock in a multi-stand continuous rolling mill

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0004598A2 (en) * 1978-04-10 1979-10-17 BROWN, BOVERI & CIE Aktiengesellschaft Mannheim Process and circuit for interstand tension control in a continuous rolling mill having individual drives
EP0004598A3 (en) * 1978-04-10 1979-10-31 Brown, Boveri & Cie Aktiengesellschaft Mannheim Process and circuit for interstand tension control in a continuous rolling mill having individual drives
EP0439663A1 (en) * 1990-02-02 1991-08-07 Siemens Aktiengesellschaft Method of controlling a continuous multistand rolling mill
EP0455381A1 (en) * 1990-05-01 1991-11-06 Allegheny Ludlum Corporation Method for controlling tension in a metal rolling mill
AU636545B1 (en) * 1992-01-28 1993-04-29 Kabushiki Kaisha Toshiba System for controlling strip thickness in rolling mills

Also Published As

Publication number Publication date
DE2860375D1 (en) 1981-03-19
EP0000855A1 (en) 1979-02-21
FR2399883B1 (en) 1980-04-18
EP0000855B2 (en) 1987-04-29
FR2399883A1 (en) 1979-03-09

Similar Documents

Publication Publication Date Title
EP3086889B1 (en) Hot rolling method, hot rolling mill and computer programm for carrying out such method
EP2167248B1 (en) Method for rolling a metal strip with adjustment of the side position of the strip and adapted rolling mill
EP0000855B1 (en) Pre-controlling process of a continuous tandem train for the hot-rolling of metals
EP1466675B1 (en) Method and device for controlling the thickness of a rolled product
FR2600562A1 (en) PROCESS AND INSTALLATION FOR MANUFACTURING SOLDER FREE TUBES
CA2259110C (en) Process to conduct a continuous cold drawing operation of a metallic band
EP1020240B1 (en) Method of tension/compression control in a multistand hot rolling mill and corresponding control system
EP0041025B1 (en) Process and device for the rolling of metal without tension
FR2469963A1 (en) ADJUSTING INSTALLATION FOR MULTI-CAGE STRETCHING AND REDUCTION ROLLER FOR TUBES
EP0000454B1 (en) Process for controlling the interstand tension during the hot-rolling of thick products.
FR2480148A1 (en) DEGREASER-REDUCER LAMINATOR FOR THE MANUFACTURE OF REDUCED DIAMETER AND WALL THICKNESS TUBES THROUGH TUBE LAMPS
CH615367A5 (en)
CA2046803C (en) Reversible reduction rolling
FR2459085A1 (en) Drawn wire coil fabricating machine - has shears for incoming wire synchronised with position of coil forming head
US4388816A (en) Method and apparatus for rolling a length of metal bar or wire
EP0560688A1 (en) Control device of a cold-working tool for skin-pass rolling sheet metal
CH513682A (en) Method of rolling a blank and rolling mill for its implementation
FR2487225A1 (en) ROLLER TRAIN FOR THE REDUCTION OF TUBES BY STRETCHING
EP0032766A1 (en) Method of rolling a length of metal bar or wire and apparatus for carrying out the method
FR2471227A1 (en) METHOD AND APPARATUS FOR CONTROLLING THE MOVEMENTS OF A HOLLOW INGOT IN THE ROLLING WITH NO PILGRIMS FOR THE OPTIMIZATION OF THE WORKING SPEED
BE673402A (en)
EP0867245A1 (en) Method for regulation of the circumferential roll velocity of roll caster
FR2586947A1 (en) Method and device for the transverse rolling of a weld-free pipe blank
JP2555894B2 (en) Stretch reducer learning control method
FR2600919A1 (en) Method and device for dressing (retouching), because of wearing, the rolls of a rolling mill, on the rolling line

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Designated state(s): DE GB SE

17P Request for examination filed
GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Designated state(s): DE GB SE

REF Corresponds to:

Ref document number: 2860375

Country of ref document: DE

Date of ref document: 19810319

PLBI Opposition filed

Free format text: ORIGINAL CODE: 0009260

26 Opposition filed

Opponent name: BROWN,BOVERI & CIE AKTIENGESELLSCHAFT

Effective date: 19811022

PUAH Patent maintained in amended form

Free format text: ORIGINAL CODE: 0009272

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: PATENT MAINTAINED AS AMENDED

27A Patent maintained in amended form

Effective date: 19870429

AK Designated contracting states

Kind code of ref document: B2

Designated state(s): DE GB SE

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: SE

Payment date: 19910521

Year of fee payment: 14

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 19910612

Year of fee payment: 14

Ref country code: DE

Payment date: 19910612

Year of fee payment: 14

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Effective date: 19920804

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SE

Effective date: 19920805

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 19920804

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Effective date: 19930501

EUG Se: european patent has lapsed

Ref document number: 78400073.9

Effective date: 19930307

APAC Appeal dossier modified

Free format text: ORIGINAL CODE: EPIDOS NOAPO

APAC Appeal dossier modified

Free format text: ORIGINAL CODE: EPIDOS NOAPO