EP3003590B1 - Method for changing the configuration of a rolling mill and rolling mill for the implementation of said method - Google Patents

Description

The subject of the invention is a method for changing the configuration of a rolling mill, as well as a rolling mill for implementing the method.

The field of the invention is more particularly that of Sexto cage mills. These Sexto mills find particular application, for example in annealing lines, or galvanizing lines, or alternatively, reversible or non-reversible offline mills, for metal band.

The mill according to the invention has a particular application, especially after annealing of the strip, to make a skin pass, often for the purpose of removing the elastic bearing from the metal strip to print a roughness and / or improve the brightness and / or improve the flatness.

A Quarto cage mill comprises a holding cage in which are provided four cylinders with parallel axes, namely respectively two working rolls, lower and upper, defining the air gap for the strip to be rolled, and two support rolls. , upper and lower, respectively bearing on the working cylinders on the opposite side to that of the air gap.

A Sexto mill comprises two additional cylinders with respect to a Quarto, namely two intermediate cylinders interposed respectively between each working roll and the corresponding support roll.

In such mills, each support cylinder, intermediate or working, is rotatably mounted at its ends on chocks, by means of bearings, for example bearings or hydrostatic bearings. These chocks are supports that can be moved in a direction parallel to the clamping plane, between the two amounts of the cage.

Conventionally, first balancing cylinders allow the displacement of the chocks of the work rolls and second balancing cylinders allow the displacement of the chocks of the intermediate rolls. These balancing cylinders allow to change the relative position of the chocks and their cylinder, allowing among other things, to open the cage to facilitate the engagement of the product to be rolled, or to move these elements to facilitate disassembly of the cylinders. These cylinders balancing can also help to bend the cylinders as developed later.

An advantage of a Sexto cage mill is the ability to use smaller diameter work rolls compared to a Quarto cage, resulting in a greater reduction in the thickness of the product to be rolled. the same rolling force.

A Sexto mill also offers the possibility of axially shifting the two intermediate rolls, or even the two working rolls, and for the purpose of applying the rolling force only over the width of the strip to be rolled, and not over any the length of the work rolls. Such a possibility of axial adjustment of the cylinders, as particularly taught in the document US 4,311,030 , makes it possible to obtain a better flatness of the product to be rolled, in particular at the edges of the rolled strip.

The rolling forces being applied only at the ends of the rolls, each cylinder can bend under the action of rolling forces, which often results in tape flatness defects.

It is then known to correct these defects by applying bending forces on both ends of each of the work rolls and / or on both ends of each of the intermediate rolls.

For this purpose, the balancing cylinders described above can be used to separate the chocks of the two work rolls, thus achieving a positive bending. Some equipment also allows to tighten the chocks of two work rolls, thus achieving a negative bending. Alternatively or additionally, a positive and / or negative bending may also be provided on the intermediate rolls.

This is known from the state of the art, in particular the document EP 0 059 417 , a Sexto rolling stand conventionally comprising two work rolls, two intermediate rolls and two support rolls.

In the rolling shaft of the document type EP 0 059 417 , the balancing cylinders are double-acting hydraulic cylinders and do not act directly on the chocks of the rolls, but only by means of bending blocks, each mounted sliding along a rail disposed over the height of one of the amounts of the cage. The displacement of the working rolls or intermediate rolls, according to the clamping plane is obtained by sliding the corresponding bending blocks relative to the amount of the cage.

In such a mill, the axial displacement of the working rolls, or the axial displacement of the intermediate rolls can be obtained by sliding their respective chocks relative to the corresponding bending blocks. For this purpose, the chocks have guide portions oriented in a direction parallel to the axes of the cylinders, for example two horizontal pins, projecting laterally on each side of the chock, able to slide respectively in corresponding parts of the two blocks of corresponding bending, for example in horizontal grooves of the two corresponding blocks.

Such a design is simple and can advantageously allow, by using asymmetric chocks, to mount in the same cage, two ranges of values of different cylinder diameters, for the working rolls and for the intermediate rolls, by simply reversing the chocks. The change from one cylinder diameter configuration to the other configuration is thus obtained by keeping the asymmetric chocks of the intermediate rolls and the asymmetric chocks of the work rolls.

These chocks are asymmetrical in that the guide portions of the chocks are shifted in a direction parallel to the clamping plane, with respect to the axis of the corresponding cylinder, which makes it possible, during the 180 ° rollover of the chocks of the work rolls. and chocks of the intermediate rolls to change the position of the axis of rotation of the chocks.

The configuration change is thus obtained by keeping the same rolling mill stand, the same bending force application means (ie the same bending blocks) for the work rolls and for the intermediate rolls, and the same chocks for the working cylinders and for the intermediate cylinders.

Such a change in configuration of the cage makes it possible to extend the production range of a rolling installation and to make this equipment more cost-effective, which keeps a maximum of equipment from one configuration to another. A rolling mill cage according to the document EP 0 059 417 however, has some disadvantages.

First of all, this cage uses double-acting hydraulic cylinders for the balancing jacks of the camber blocks, which generate games, in particular during the reversal of the cambering direction, namely from a positive camber to a camber. negative, or vice versa. These double-acting hydraulic cylinders create discontinuities in operation, which can be particularly penalizing during certain productions.

In addition, and according to the findings of the inventors, the balancing cylinders do not act directly on the chocks of the rolls, but only through said bending blocks, themselves slidably mounted, each by means of a rail or equivalent along the amounts of the cage.

According to the findings of the inventor, these bending blocks are likely to create significant friction which will be greatly accentuated during the axial displacements of the intermediate rolls and / or work rolls, conventionally made to apply the rolling force only on the width of the strip to be rolled.

Indeed, these axial displacements are obtained by displacement of the chocks with respect to the bending blocks. During such displacements, the vertical forces transmitted by each chock to the corresponding bending block are no longer centered along the axis of said corresponding bending block, but on the contrary strongly offset from it. Such misalignment causes a tilting force on the bending block, causing the increase in friction between the block and the amount. It is understood that such friction disturb the accuracy of the control of the bending forces to be applied.

In order to limit this defect, for a bending block mill design according to the document EP 0 059 417 it is known to limit the amplitude of the axial displacements of the cylinders to +/- 160 mm, which generally requires the use for the working cylinders and the intermediate cylinders of particular profiles, in the form of bottles, for the cylinders, such as that taught by the document EP 0 543 014 B1 , still known as the Continuous Variable Crown (CVC). With traditional roll profiles typically comprising a cylindrical length section followed by a conical length section, the necessary axial displacement stroke becomes too large and this camber block design is often considered unsuitable.

Also known from the state of the art Quarto rolling cages suitable for use in the same cage, two ranges of different working roll diameters, keeping the same chocks. Such a change in configuration of the cage makes it possible to extend the production range of a rolling installation and to make this equipment more cost-effective, which keeps a maximum of equipment from one configuration to another.

In this state of the art, the chocks have sliding faces, parallel, on either side of the clamping plane, and intended to cooperate with guide faces of the windows oriented in the direction of clamping. Each chock has, on each side, laterally, a projecting pin intended to serve as a support for balancing cylinders of the single-acting type, operating only thrust. Some of the balancing cylinders are provided below the tenon and act to the thrust on the underside of the tenon chocks to arch the corresponding working cylinder in a first direction of bending. The other single-acting cylinders are provided on the other side of the post, above the tenon and act to the push on the upper face of the tenon chocks to arch the working cylinder in the other direction.

Such a design using only single-acting balancing cylinders to bend the rollers, in one direction or the other, does not create a discontinuity when inverting the bending directions.

The chocks are asymmetrical, the tenons of the chocks of each working roll being offset with respect to the axis of the cylinder, in a direction parallel to the clamping plane. The configuration change is performed by turning the chocks of the work rolls 180 ° to change from a diameter value range to another work roll value range.

In such a Quarto rolling mill design, and according to the findings of the inventors, the single-acting balancing cylinders cooperating with one and the same chock are arranged on either side of the tenons of the chocks, and thus occupy a large vertical space requirement for such a design can be duplicated to a rolling mill cage of the Sexto type.

Duplicate such an arrangement of the balancing cylinders for the chocks of the work rolls and another additional arrangement of balancing cylinders for the chocks intermediate cylinders is not possible because of the vertical size of this solution, greater than the space available in a cage type Sexto.

The object of the present invention is to overcome the aforementioned drawbacks by proposing a method of changing the Sexto-type rolling mill configuration from a working roll diameter value range to another distinct range. The invention allows the passage from one configuration to another, retaining in particular the same chocks, the same cambering means, and the same support cylinders, and possibly the same intermediate cylinders.

The invention also relates to a rolling mill which is suitable for carrying out the process, of improved performance compared to the state of the art, such as interchangeable roll mills by chock rolls, in particular on the aspects of the control of bending, or with regard to the values of the possible amplitudes of axial displacement of the intermediate rolls.

Other aims and advantages will appear from the description which is given by way of non-limiting example.

• une cage de maintien,
• un ensemble de cylindres superposés à axes sensiblement parallèles comprenant deux cylindres de travail, inférieur et supérieur, deux cylindres intermédiaires, inférieur et supérieur, et deux cylindres de soutien , respectivement inférieur et supérieur,
• chaque cylindre ayant deux extrémités montées rotatives, chacune sur un palier porté par une empoise,
• des moyens d'application d'un effort de serrage entre les empoises des cylindres de soutien,
• des moyens d'application d'efforts verticaux de cambrage sur les cylindres de travail, comprenant deux ensembles de vérins hydrauliques,
• des moyens d'application d'efforts verticaux de cambrage sur les cylindres intermédiaires, comprenant deux ensembles de vérins hydrauliques,

procédé dans lequel les empoises des cylindres de travail et les empoises des cylindres intermédiaires sont asymétriques et dans lequel on fait passer le laminoir d'une première configuration de plage de diamètres de cylindres de travail à une deuxième configuration de diamètres différents de cylindres de travail en conservant les empoises, par retournement des empoises des cylindres de travail et par retournement des empoises des cylindres intermédiaires, en conservant la même cage, les mêmes moyens d'application d'un effort de serrage entre les empoises des cylindres de soutien, les mêmes moyens d'application d'efforts verticaux de cambrage sur les cylindres de travail, les mêmes moyens d'application d'efforts verticaux de cambrage sur les cylindres intermédiaires, et le même type de cylindres de soutien.Also the invention relates firstly to a method of changing the configuration of a rolling mill comprising:

• a cage of maintenance,
• a set of superimposed cylinders with substantially parallel axes comprising two working cylinders, lower and upper, two intermediate cylinders, upper and lower, and two support cylinders, respectively lower and upper,
• each cylinder having two ends rotatably mounted, each on a bearing carried by a chock,
• means for applying a clamping force between the chocks of the support rolls,
• means for applying vertical bending forces on the work rolls, comprising two sets of hydraulic cylinders,
• means for applying vertical bending forces on the intermediate rolls, comprising two sets of hydraulic cylinders,

process in which the chocks of the work rolls and the chocks of the intermediate rolls are asymmetrical and in which the rolling mill is passed from a first work roll diameter range configuration to a second configuration of different work roll diameters. maintaining the chocks, by turning the chocks of the work rolls and by turning the chocks of the intermediate rolls, keeping the same cage, the same means for applying a clamping force between the chocks of the support rolls, the same means application of vertical bending forces on the work rolls, the same means for applying vertical bending forces on the intermediate rolls, and the same type of support rolls.

• on utilise pour les empoises des cylindres de travail et pour les empoises des cylindres intermédiaires des supports comprenant quatre organes d'appui, disposés latéralement, avec d'une part, deux organes d'appui en saillie d'un côté de l'empoise, à savoir un organe d'appui supérieur et un organe d'appui inférieur définissant un premier inter-espace, et d'autre part, deux organes d'appui en saillie de l'autre côté de l'empoise, à savoir un organe d'appui supérieur et un organe d'appui inférieur définissant un second inter-espace,
• les vérins hydrauliques des moyens d'application d'efforts verticaux de cambrage sur les cylindres de travail sont des vérins simple effet disposés dans les premiers et seconds inter-espaces des empoises des cylindres de travail, les vérins disposés dans un même inter-espace étant en recouvrement, lesdits vérins étant destinés à coopérer à la poussée, pour partie, avec les organes d'appui supérieurs pour cambrer le cylindre de travail dans un premier sens et pour le reste avec les organes d'appui inférieurs pour cambrer le cylindre de travail dans l'autre sens,
• les vérins hydrauliques des moyens d'application d'efforts verticaux de cambrage sur les cylindres intermédiaires sont des vérins simple effet disposés dans les premiers et seconds inter-espaces des empoises des cylindres intermédiaires, les vérins disposés dans un même inter-espace étant en recouvrement, les vérins étant destinés à coopérer à la poussée pour partie avec les organes d'appui supérieurs pour cambrer le cylindre intermédiaire dans un premier sens et pour le reste avec les organes d'appui inférieurs pour cambrer le cylindre intermédiaire dans l'autre sens.

According to the process according to the invention:

• for the chocks of the work rolls and the chocks of the intermediate rolls are used supports comprising four support members, arranged laterally, with, on the one hand, two bearing members projecting from one side of the chock, namely an upper support member and a lower support member defining a first inter-space, and secondly, two support members projecting from the other side of the chock, namely a body of upper support and a lower support member defining a second inter-space,
• the hydraulic cylinders means for applying vertical forces of bending on the working cylinders are single-acting cylinders arranged in the first and second inter-spaces chocks work rolls, the cylinders arranged in the same inter-space being in overlap, said cylinders being intended to cooperate with the thrust, in part, with the upper support members to bend the work roll in a first direction and for the rest with the lower support members to bend the work roll in the other direction,
• the hydraulic cylinders means for applying vertical forces of bending on the intermediate cylinders are single-acting cylinders arranged in the first and second inter-spaces of the chocks of the intermediate cylinders, the cylinders arranged in the same inter-space being in overlap , the jacks being intended to cooperate with the thrust partly with the upper bearing members to bend the cylinder intermediate in a first direction and for the rest with the lower support members to arch the intermediate cylinder in the other direction.

According to the invention, said rolling mill comprises means for adjusting the axial displacement of the intermediate rolls and in which these means comprise supports mounted sliding relative to the cage, the supports carrying the hydraulic cylinders of said means for applying vertical forces of cambering on the intermediate cylinders so as to obtain the axial displacement of the intermediate cylinders without relative movement between the chocks and said hydraulic cylinders.

According to an advantageous embodiment, the same intermediate rolls are maintained from the first configuration of the rolling mill to the second configuration.

Alternatively, it is also possible to change the diameter of the intermediate rolls, from the first configuration of the rolling mill to the second configuration.

• la première configuration du laminoir permet le montage de cylindres de travail de diamètre compris entre 800 mm et 500 mm et la deuxième configuration du laminoir permet le montage de cylindre de travail de diamètre compris entre 500 mm et 250 mm;
• on utilise des empoises identiques pour les cylindres de travail, supérieur et inférieur et des empoises identiques pour les cylindres intermédiaires, supérieur et inférieur ;
• les tiges des vérins desdits moyens d'application d'efforts verticaux de cambrage sur les cylindres de travail et/ou sur les cylindres intermédiaires sont destinés à être en simple appui sur lesdits organes d'appui ;
• les empoises des cylindres de travail et des cylindres intermédiaires présentent des faces de glissement destinées à coopérer avec des faces de guidage de la cage et dans lequel, de préférence, les faces de glissement des empoises des cylindres de travail et/ou des cylindres intermédiaires sont situées aux extrémités des organes d'appui.

According to optional features of the method according to the invention, taken alone or in combination:

• the first configuration of the rolling mill allows the assembly of working rolls with a diameter of between 800 mm and 500 mm and the second configuration of the rolling mill allows the assembly of work roll with a diameter of between 500 mm and 250 mm;
• identical chocks are used for the upper and lower work rolls and identical chocks for the upper and lower intermediate rolls;
• the rods of the cylinders of said vertical bending force application means on the working cylinders and / or the intermediate cylinders are intended to be in simple support on said support members;
• the chocks of the working rolls and intermediate rolls have sliding faces intended to cooperate with guide faces of the cage and in which, preferably, the sliding faces of the chocks of the work rolls and / or the intermediate rolls are located at the ends of the support members.

• une cage de maintien,
• un ensemble de cylindres superposés à axes sensiblement parallèles comprenant deux cylindres de travail, inférieur et supérieur, deux cylindres intermédiaires, inférieur et supérieur, et deux cylindres de soutien, respectivement inférieur et supérieur,
• chaque cylindre ayant deux extrémités montées rotatives, chacune sur un palier porté par une empoise,
• des moyens d'application d'un effort de serrage entre les empoises des cylindres de soutien,
• des moyens d'application d'efforts verticaux de cambrage sur les cylindres de travail, comprenant deux ensembles de vérins hydrauliques,
• des moyens d'application d'efforts verticaux de cambrage sur les cylindres intermédiaires, comprenant deux ensembles de vérins hydrauliques,
• les empoises des cylindres de travail et les empoises des cylindres intermédiaires sont des empoises asymétriques de telle façon à permettre le passage du laminoir d'une première configuration de plage de diamètres de cylindres de travail à une deuxième configuration de diamètres différents de cylindres de travail en conservant les empoises, par retournement des empoises des cylindres de travail et par retournement des empoises des cylindres intermédiaires, en conservant la même cage, les mêmes moyens d'application d'un effort de serrage entre les empoises des cylindres de soutien, les mêmes moyens d'application d'efforts verticaux de cambrage sur les cylindres de travail, les mêmes moyens d'application d'efforts verticaux de cambrage sur les cylindres intermédiaires, et le même type de cylindres de soutien.

The invention also relates to a rolling mill as such, suitable for carrying out the method comprising:

• a cage of maintenance,
• a set of superimposed cylinders with substantially parallel axes comprising two working cylinders, lower and upper, two intermediate cylinders, upper and lower, and two support cylinders, respectively lower and upper,
• each cylinder having two ends rotatably mounted, each on a bearing carried by a chock,
• means for applying a clamping force between the chocks of the support rolls,
• means for applying vertical bending forces on the work rolls, comprising two sets of hydraulic cylinders,
• means for applying vertical bending forces on the intermediate rolls, comprising two sets of hydraulic cylinders,
• the chocks of the work rolls and the chocks of the intermediate rolls are asymmetrical chocks so as to allow the mill to pass from a first work roll diameter range configuration to a second configuration of different diameters of working rolls. maintaining the chocks, by turning the chocks of the work rolls and by turning the chocks of the intermediate rolls, keeping the same cage, the same means for applying a clamping force between the chocks of the support rolls, the same means application of vertical bending forces on the work rolls, the same means for applying vertical bending forces on the intermediate rolls, and the same type of support rolls.

• les empoises des cylindres de travail et les empoises des cylindres intermédiaires sont des supports comprenant quatre organes d'appui, disposés latéralement, avec d'une part, deux organes d'appui en saillie d'un côté de l'empoise, à savoir un organe d'appui supérieur et un organe d'appui inférieur définissant un premier inter-espace, et d'autre part, deux organes d'appui en saillie de l'autre côté de l'empoise, à savoir un organe d'appui supérieur et un organe d'appui inférieur définissant un second inter-espace,
• les vérins hydrauliques des moyens d'application d'efforts verticaux de cambrage sur les cylindres de travail sont des vérins simple effet disposés dans les premiers et seconds inter-espaces des empoises des cylindres de travail, les vérins disposés dans un même inter-espace étant en recouvrement, lesdits vérins étant destinés à coopérer à la poussée, pour partie, avec les organes d'appui supérieurs pour cambrer le cylindre de travail dans un premier sens et pour le reste avec les organes d'appui inférieurs pour cambrer le cylindre de travail dans l'autre sens,
• les vérins hydrauliques des moyens d'application d'efforts verticaux de cambrage sur les cylindres intermédiaires sont des vérins simple effet disposés dans les premiers et seconds inter-espaces des empoises des cylindres intermédiaires, les vérins disposés dans un même inter-espace étant en recouvrement, les vérins étant destinés à coopérer à la poussée pour partie avec les organes d'appui supérieurs pour cambrer le cylindre intermédiaire dans un premier sens et pour le reste avec les organes d'appui inférieurs pour cambrer le cylindre intermédiaire dans l'autre sens.

According to the rolling mill according to the invention:

• the chocks of the work rolls and the chocks of the intermediate rolls are supports comprising four support members, arranged laterally, with, on the one hand, two support members projecting from one side of the chock, namely a upper support member and a lower support member defining a first inter-space, and other on the other hand, two support members projecting from the other side of the chock, namely an upper support member and a lower support member defining a second inter-space,
• the hydraulic cylinders means for applying vertical forces of bending on the working cylinders are single-acting cylinders arranged in the first and second inter-spaces chocks work rolls, the cylinders arranged in the same inter-space being in overlap, said cylinders being intended to cooperate with the thrust, in part, with the upper support members to bend the work roll in a first direction and for the rest with the lower support members to bend the work roll in the other direction,
• the hydraulic cylinders means for applying vertical forces of bending on the intermediate cylinders are single-acting cylinders arranged in the first and second inter-spaces of the chocks of the intermediate cylinders, the cylinders arranged in the same inter-space being in overlap , the jacks being intended to cooperate with the thrust part with the upper support members to arch the intermediate cylinder in a first direction and for the rest with the lower support members to arch the intermediate cylinder in the other direction.

According to the invention, the rolling mill comprises means for adjusting the axial displacement of the intermediate rolls and wherein these means comprise supports mounted sliding relative to the cage, the supports carrying the hydraulic cylinders of said means for applying vertical forces of cambering on the intermediate rolls such that the axial displacement of the intermediate rolls is obtained without relative movement between the chocks and said hydraulic cylinders;

According to an advantageous embodiment, the passage of the rolling mill, from the first configuration to the second configuration, is possible while maintaining the same intermediate cylinders.

• les tiges des vérins desdits moyens d'application d'efforts verticaux de cambrage sur les cylindres de travail et/ou sur les cylindres intermédiaires sont destinées à être en simple appui sur lesdits organes d'appui ;
• les empoises des cylindres de travail et des cylindres intermédiaires présentent des faces de glissement destinées à coopérer avec des faces de guidage de la cage ;
• les faces de glissement des empoises des cylindres de travail et/ou des cylindres intermédiaires sont situées aux extrémités des organes d'appui.

According to optional characteristics of the rolling mill taken alone or in combination:

• the rods of the cylinders of said vertical bending force application means on the work rolls and / or the intermediate rolls are intended to be in simple support on said support members;
• the chocks of the working rolls and intermediate rolls have sliding faces intended to cooperate with guide faces of the cage;
• the sliding faces of the chocks of the work rolls and / or the intermediate rolls are located at the ends of the support members.

• La figure 1 et la figure 2 sont des vues d'un laminoir conforme à l'invention dans ladite première configuration du laminoir portant respectivement des cylindres de travail de diamètres de 570 mm (figure 1) et de 620 mm (figure 2).
• La figure 3 et la figure 4 sont des vues du laminoir selon les figures 1 et 2, dans ladite deuxième configuration du laminoir, après retournement des empoises des cylindres de travail et intermédiaires, portant respectivement des cylindres de travail de diamètres de 400 mm (figure 3) et de 450 mm (figure 4).
• La figure 5 est une vue de détail de la forme générale d'une empoise utilisée pour les cylindres de travail et les cylindres intermédiaires.

The invention will be better understood on reading the description accompanied by the appended figures, among which:

• The figure 1 and the figure 2 are views of a rolling mill according to the invention in said first configuration of the rolling mill respectively carrying working cylinders with diameters of 570 mm ( figure 1 ) and 620 mm ( figure 2 ).
• The figure 3 and the figure 4 are views of the rolling mill according to the Figures 1 and 2 in said second configuration of the rolling mill, after reversing the chocks of the working and intermediate rolls respectively carrying working cylinders with diameters of 400 mm ( figure 3 ) and 450 mm ( figure 4 ).
• The figure 5 is a detail view of the general shape of a chock used for the work rolls and the intermediate rolls.

Also the invention relates to a rolling mill 1 comprising a holding cage 2 having pairs of uprights 20, 21 spaced apart and arranged at both ends of the cage. The amounts 20,21 of each pair define between them an access window for the maintenance of the cages.

The rolling mill is of the Sexto type and comprises a set of superimposed cylinders with substantially parallel axes comprising two working rolls 3,4; 3 ', 4', lower and upper, two intermediate rollers 5,6, lower and upper, and two rolls support 7.8, respectively lower and upper.

The two working rolls 3 and 4 are located on either side of the strip to be rolled, their spacing defining the operating gap. Each intermediate cylinder 5 or 6 is interposed between the working cylinder 3 or 4 and the corresponding support cylinder 7 or 8.

Each working roll 3 or 4 has two rotatably mounted ends, each on a bearing P1 carried by a chock E1. Similarly, each intermediate cylinder 5 or 6 has two rotatably mounted ends, each on a bearing P2 carried by a chock E2. The support cylinders 7 or 8 also have two rotatably mounted ends, each mounted on a bearing carried by a chock.

The chocks E1 of the work rolls, the chocks E2 of the intermediate rolls and the chocks of the support rollers 7,8 are slidably mounted in a direction parallel to the clamping plane, so as to allow the opening of the cage or its closure. or facilitate maintenance and dismantling operations.

The rolling mill has means for applying a clamping force between the chocks of the support rolls. These conventionally hydraulic means are not illustrated because well known to those skilled in the art.

The rolling mill 1 also comprises means 9 for applying vertical bending forces to the working rolls 3,4; 3 ', 4', comprising two sets of hydraulic cylinders V1, V2, V3 and means of application vertical bending forces on the intermediate cylinders, comprising two sets of hydraulic cylinders V1 ', V2', V3 '.

According to the rolling mill according to the invention, the chocks E1 of the working rolls 3,4; 3 ', 4' and the chocks E2 of the intermediate rolls 5,6 are supports comprising four support members O1, O2, O3, O4; O1 ', O2', O3 ', O4', as illustrated in detail by way of non-limiting example in the figure 5 .

It should be noted that, for reasons of simplification, figure 5 illustrates both the general shape of a chock E1 of the working rolls and a chock E2 of the intermediate rolls. Preferably, the chocks E1 of the working rolls and the chocks E2 of the intermediate rolls are not identical, the dimensions of the chocks E1 of the working rolls being preferably lower than those of the intermediate rolls.

The four support members O1, O2, O3, O4; O1 ', O2', O3 ', O4' are arranged laterally to the chocks E1 or E2. Thus the chocks E1 of the working cylinders each have, on the one hand, two support members O1, O2; protruding from one side of the chock E1, namely an upper support member O1 and a lower support member O2 defining a first inter-space, and secondly, two support members O3, O4 protruding from the other side of the chock, namely an upper support member O3 and a lower support member O4 defining a second inter-space.

Similarly, the chocks E2 of the intermediate rolls each have, on the one hand, two bearing members O1 ', O2' projecting from one side of the chock E2, namely an upper support member O1 'and a lower support member O2' defining a first inter-space, and secondly, two support members O3 ', O4' projecting from the other side of the chock, namely an upper support member O3 'and a lower support member O4' defining a second inter-space.

The hydraulic cylinders V1, V2, V3 of the means 9 for applying vertical bending forces on the work rolls are cylinders arranged in the first and second inter-spaces of the chocks of the work rolls 3, 4; 3 '; 4 '.

The cylinders V1, V2, V3 disposed in the same inter-space are parallel to each other and substantially overlapping at least over part of their length as illustrated by way of non-limiting example to the figure 5 . In this example and, more generally, the bodies of the cylinders V1, V2, V3 extend in length along the same height level and may possibly be constituted by the same hydraulic block. An overlap of the cylinders makes it possible to limit the vertical dimensions of the means 9.

The cylinders V1, V2, V3 are intended to cooperate with the thrust, in part, with the upper support members O1, O3 for arching the working rolls 3; 3 ';4;4' in a first direction and for the remain with the lower support members O2, O4 for arching the working rolls 3; 3 ';4;4' in the other direction. According to an embodiment illustrated in figure 5 , in the same inter-space rod of a jack V1 is intended to be in single support on one of the support members, lower or upper, while the rods of the other two cylinders V2, V3, arranged from and other V1 cylinder, are intended to be in simple support on the other supporting bodies, upper or lower.

Likewise, the hydraulic jacks of the means 10 for applying vertical bending forces on the intermediate cylinders 5, 6 are jacks arranged in the first and second interspaces of the chocks E2 of the intermediate rolls.

The jacks V1 ', V2', V3 'arranged in the same inter-space are substantially parallel to each other and overlapping, at least over part of their length as illustrated by way of non-limiting example to the figure 5 . In this example and, more generally, the bodies of the cylinders V1 ', V2', V3 'extend in length along the same height level and may possibly be constituted by the same hydraulic block. An overlap of the cylinders makes it possible to limit the vertical dimensions of the means 10.

The jacks V1 ', V2', V3 'are intended to cooperate with the thrust partly with the upper bearing members O1', O3 'for arching the intermediate cylinder in a first direction and for the rest with the bearing members lower O2 ', O4' to arch the intermediate cylinder in the other direction.

The cylinders V1, V2, V3 and / or V1 ', V2', V3 'may be single acting cylinders. Working only with the push in one direction of bending or in the other, they do not create any discontinuity during a reversal of the direction of bending. Moreover, the cylinders V1, V2, V3 and / or V1 ', V2', V3 'acting directly on the chocks E1 or E2, the control of the bending forces is facilitated.

According to an embodiment illustrated in figure 5 , in the same inter-space rod of a jack V1 'is intended to be in single support on one of the support members, lower or upper, while the rods of the other two cylinders V2', V3 ', arranged on either side of the jack V1 ', are intended to be in simple support on the other support members, upper or lower.

The chocks E1 of the work rolls 3,4; 3 ', 4' have sliding faces, on either side of the chock E1, parallel to each other, intended to cooperate with guide faces, preferably provided on the uprights of the cage.

Similarly, the chocks E2 of the intermediate cylinders 5, 6 have sliding faces on either side of the chock E2, parallel to each other, intended to cooperate with guide faces, preferably provided on the uprights of the cage. Preferably, and as illustrated in figure 5 , the sliding faces S of the chocks E1, E2 of the working rolls and / or intermediate rolls are located at the ends of the support members O1, O2, O3, O4; O1 ', O2', O3 ', O4'.

According to this embodiment, the sliding faces S may comprise pads, substantially parallel to each other and to the clamping plane, secured to the ends of the support members O1, O2, O3, O4; O1 ', O2', O3 ', O4'.

Alternatively, the guide between the cage 2 and the chocks E1, E2 can be obtained by providing the sliding faces, laterally to the body of the chocks, at each inter-space.

According to an essential characteristic of the invention, the chocks E1 of the work rolls 3,4; 3 ', 4' and the chocks E2 of the intermediate rolls 5,6 are asymmetrical chocks so as to allow the passage of the rolling mill. a first configuration C1 range of working cylinder diameters 3,4 (see figure 1 or 2 ) at a second configuration C2 of different diameters of working rolls 3 ', 4' (see figure 3 or 4 ).

Preferably, the same intermediate cylinders 5,6 are retained from the first configuration C1 to the second configuration of the rolling mill C2. However, it is possible, according to another alternative, to change intermediate cylinder diameters from the first configuration C1 to the second configuration C2.

Asymmetric means that the support members O1, O2, O3, O4; O1 ', O2', O3 ', O4' of the chocks E1 or E2 are not distributed, in the direction of the amounts equidistant from the support axis of the cylinder of the chock E1 or E2.

By returning the chocks E1 or E2 and making them engage with the same jacks V1, V2, V3 or V1 ', V2', V3 ', it is then possible to shift the position of the axis of the cylinder, without changing the position cylinders.

According to one embodiment given by way of non-limiting example, the first configuration C1 of the rolling mill 1 may allow the assembly of working rolls with a diameter of between 800 mm and 500 mm, preferably 670 mm and 520 mm, for example between 620 mm and 570 mm and the second configuration C2 of the rolling mill allows the assembly of work roll of diameter between 500 mm and 250 mm, preferably between 500 mm and 350 mm, for example between 450 mm and 400 mm. Advantageously, the change of configuration of the rolling mill is obtained by keeping the chocks E1, E2, by inverting the chocks E1 of the work rolls and by turning the chocks E2 of the intermediate rolls, while retaining the same stand 2, the same means of application. a clamping force between the chocks of the support cylinders, the same means 9 for applying vertical forces of bending on the working rolls, the same means 10 for applying vertical forces of bending on the intermediate rolls , and the same type of support cylinders 7.8, and possibly the same intermediate cylinders 5.6.

During this change of configuration, the cage 2, the means for applying a clamping force between the chocks of the support rolls, the means 9 for applying vertical forces of bending on the work rolls, the means 10 application of vertical bending forces on the intermediate rolls, and the support rollers 7,8 are not removed from the rolling mill.

On the other hand, the work rolls 3,4 (resp. 3 ', 4') are removed with their chocks E1. Once separated from the cylinders, the chocks E1 are assembled on the working cylinders 3 ', 4' (resp 3,4) of different diameters, in the inverted position. The new work rolls with their returned chocks are mounted in the cage 2.

Similarly, the intermediate cylinders 5.6 are removed with their E2 chocks. In the case where the intermediate cylinders 5.6 are retained, the E2 chocks are simply returned out of the cage 2, before being mounted again in the cage 2. In the case of a change of intermediate cylinders, diameters E2 chocks are separated from the cylinders and are assembled on the intermediate cylinders of different diameters. The new intermediate cylinders with their returned chocks are then mounted in the cage 2. Preferably, identical E1 chocks are used for the working cylinders, upper and lower and identical E2 chocks for the intermediate rolls, upper and lower. The chocks E1 and / or E2 of the upper rollers are simply reversed relative to the chocks E1 and / or E2 of the lower rolls.

Preferably, said rolling mill 1 comprises means for adjusting the axial displacement of the intermediate rolls. Advantageously, these means comprise supports 11, 12, 13, 14 slidably mounted relative to the cage, in a direction parallel to the axis of the intermediate cylinder, the supports 11, 12, 13, 14 carrying hydraulic cylinders V1 ', V2 ', V3' of said means 10 for applying vertical bending forces on the intermediate cylinders 5, 6.

The axial adjustment of the intermediate cylinders 5, 6, in particular in order to adapt the rolling force only to the width of the strip to be rolled is thus obtained without relative movement between the chocks E2 of the intermediate rolls and the said hydraulic jacks V1 ', V2 ', V3' corresponding. Such a design allows large axial adjustment strokes greater than ± 160 mm such as for example ± 250 mm and thus allows the user of traditional intermediate cylinders having a section of cylindrical length followed by a conical section, or cylinders to variable profiles of different shapes because they are more progressive.

The mill according to the invention and the method of change of configuration finds an application in the lines comprising an annealing operation, such as, for example, galvanizing lines or continuous annealing lines, or in offline mills, such as, for example, reversing mills or discontinuous rolling mills.

Naturally other embodiments could have been envisaged without departing from the scope of the invention as defined by the claims below.

NOMENCLATURE

• 1. Rolling mill,
• 2. Cage,
• 3, 4. Work rolls,
• 3 ', 4'. Work rolls,
• 5, 6. Intermediate cylinders,
• 7, 8. Support cylinders,
• 9. Means for applying vertical forces of bending on the work rolls,
• 10. Means for applying vertical forces of bending on the intermediate cylinders,
• 11, 12, 13, 14. Supports means for adjusting the axial displacement of the intermediate cylinders,
• 20, 21. Cage uprights,
• C1. First configuration,
• C2. Second configuration,
• E1. Cylinder work cylinders,
• E2. Intermediate cylinder shells,
• O1, O2, O3, O4. Supporting members of chocks of work rolls,
• O1 ', O2', O3 ', O4'. Supporting bodies of chocks of intermediate rolls,
• S. Slip sides (E1 or E2),
• V1, V2, V3. Cylinders means for applying vertical forces of bending on the work rolls,
• V1 ', V2', V3 '. Cylinders means for applying vertical forces of bending on the intermediate cylinders.

Claims (14)

1. Method for changing the configuration of a rolling mill (1) comprising,

   - a holding cage (2),

   - a set of cylinders placed one above the other, with substantially parallel axes, comprising two working cylinders (3, 4; 3', 4'), bottom and top, two intermediate cylinders (5, 6), bottom and top, and two support cylinders (7, 8), respectively bottom and top,

   - each cylinder having two ends mounted so as to rotate, each on a bearing carried by a chock,

   - means for applying a clamping force between the chocks of the support cylinders,

   - means (9) for applying vertical camber forces on the working cylinders, comprising two sets of hydraulic actuators,

   - means (10) for applying vertical camber forces on the intermediate cylinders, comprising two sets of hydraulic actuators,
   a method in which the chocks (E1) of the working cylinders (3, 4; 3', 4') and the chocks (E2) of the intermediate cylinders (5, 6) are asymmetric and in which the rolling mill is changed from a first diameter-range configuration (C1) of working cylinders (3, 4) to a second configuration (C2) with different diameters of working cylinders (3', 4') while keeping the chocks (E1, E2), by turning over the chocks (E1) of the working cylinders and turning over the chocks (E2) of the intermediate cylinders, while keeping the same cage (2), the same means for applying a clamping force between the chocks of the support cylinders, the same means (9) for applying vertical camber forces on the working cylinders, the same means (10) for applying vertical camber forces on the intermediate cylinders, and the same type of support cylinder (7, 8)
   characterised in that:

   - for the chocks (E1) of the working cylinders (3, 4; 3', 4') and for the chocks (E2) of the intermediate cylinders (5, 6), use is made of supports comprising four support members (O1, O2, O3, O4 ; O1', O2', O3', O4'), disposed laterally, with firstly two support members (O1, O2, O1', O2') projecting on one side of the chock, namely a top support member (O1; O1') and a bottom support member (O2, O2') defining a first interspace, and secondly two support members (O3, O4; O3', O4') projecting on the other side of the chock, namely a top support member (O3; O3') and a bottom support member (O4; O4') defining a second interspace,

   - the hydraulic actuators of the means (9) for applying vertical camber forces on the working cylinders are single-acting actuators disposed in the first and second interspaces of the chocks of the working cylinders (3, 4; 3', 4'), the actuators (VI, V2, V3) disposed in one and the same interspace being overlapping, said actuators being intended to cooperate thrustingly, in some cases, with the top support members (01, 03) in order to camber the working cylinders (3, 3; 4, 4') in a first direction and for the remainder with the bottom support members (O2, O4) in order to camber the working cylinder (3; 3'; 4; 4') in the other direction,

   - the hydraulic actuators of the means (10) for applying vertical camber forces on the intermediate cylinders (5, 6) are single-acting actuators disposed in the first and second interspaces of the chocks of the intermediate cylinders, the actuators (V1', V2', V3') disposed in one and the same interspace being overlapping, the actuators being intended to cooperate thrustingly, in some cases, with the top support members (O1', O3') in order to camber the intermediate cylinder in a first direction and for the remainder with the bottom support members (O2', O4') in order to camber the intermediate cylinder in the other direction,
   and in which said rolling mill (1) comprises means for adjusting the axial movement of the intermediate cylinders and in which these means comprise supports (11, 12, 13, 14) mounted so as to be able to slide with respect to the cage, the supports taking the hydraulic actuators (V1', V2', V3') of said means of applying vertical camber forces to the intermediate cylinders (5, 6) so that the axial movement of the intermediate cylinders is obtained without relative movement between the chocks (E2) and said hydraulic actuators (V1', V2', V3').
2. Method according to claim 1, in which the same intermediate cylinders (5, 6) are kept from the first configuration (C1) of the rolling mill to the second configuration (C2).
3. Method according to claim 1, in which the diameters of intermediate cylinders are changed from the first configuration (C1) of the rolling mill to the second configuration (C2).
4. Method according to any of claims 1 to 3, in which the first configuration (C1) of the rolling mill (1) enables working cylinders with a diameter of between 800 mm and 500 mm to be mounted and the second configuration (C2) of the rolling mill enables a working cylinder with a diameter between 500 mm and 250 mm to be mounted.
5. Method according to claim 4, in which the first configuration (C1) of the rolling mill (1) enables working cylinders with a diameter of between 670 mm and 520 mm to be mounted and the second configuration (C2) of the rolling mill enables a working cylinder with a diameter of between 500 mm and 350 mm to be mounted.
6. Method according to any of claims 1 to 5, in which identical chocks (E1) are used for the working cylinders, top and bottom, and identical chocks (E2) for the intermediate cylinders, top and bottom.
7. Method according to any of claims 1 to 6, in which the rods of the actuators (VI, V2, V3; V1', V2', V3') of said means (9; 10) for applying vertical camber forces to the working cylinders and/or to the intermediate cylinders are intended to be in simple abutment on said support members (O1, O2, O3, O4 ; O1', O2', O3', O4').
8. Method according to any of claims 1 to 7, in which the chocks (E1, E2) of the working cylinders and of the intermediate cylinders have sliding faces (S) intended to cooperate with guide faces of the cage and in which the sliding faces (S) of the chocks (E1, E2) of the working cylinders and/or of the intermediate cylinders are situated at the ends of the support members (O1, O2, O3, O4 ; O1', O2', O3', O4').
9. Rolling mill (1) comprising:

   - a holding cage (2),

   - a set of cylinders placed one above the other, with substantially parallel axes, comprising two working cylinders (3, 4; 3', 4'), bottom and top, two intermediate cylinders (5, 6), bottom and top, and two support cylinders (7, 8), respectively bottom and top,

   - each cylinder having two ends mounted so as to rotate, each on a bearing carried by a chock,

   - means for applying a clamping force between the chocks of the support cylinders,

   - means (9) for applying vertical camber forces on the working cylinders, comprising two sets of hydraulic actuators,

   - means (10) for applying vertical camber forces on the intermediate cylinders, comprising two sets of hydraulic actuators,

   - the chocks (E1) of the working cylinders (3, 4; 3', 4') and the chocks (E2) of the intermediate cylinders (5, 6) are asymmetric chocks so as to enable the rolling mill to pass from a first diameter-range configuration (C1) of working cylinders (3,4) to a second configuration (C2) of different diameters of working cylinders (3', 4') while keeping the chocks (E1, E2), by turning over the chocks (E1) of the working cylinders and turning over the chocks (E2) of the intermediate cylinders, keeping the same cage (2), the same means of applying a clamping force between the chocks of the support cylinders, the same means (9) of applying vertical camber forces to the working cylinders, the same means (10) of applying vertical camber forces to the intermediate cylinders, and the same type of support cylinder (7, 8),
   characterised in that:

   - the chocks (E1) of the working cylinders (3, 4; 3', 4') and the chocks (E2) of the intermediate cylinders are supports comprising four support members (O1, O2, O3, O4 ; O1', O2', O3', O4'), disposed laterally, with firstly two support members (O1, O2; O1', O2') projecting on one side of the chock, namely a top support member (O1, O1') and a bottom support member (02; O2') defining a first interspace, and secondly two support members (O3, O4 ; O3', O4') projecting on the other side of the chock, namely a top support member (O3, O3') and a bottom support member (O4, O4') defining a second interspace,

   - the hydraulic actuators of the means (9) for applying vertical camber forces on the working cylinders are single-acting actuators disposed in the first and second interspaces of the chocks of the working cylinders (3, 4; 3', 4'), the actuators (VI, V2, V3) disposed in one and the same interspace being overlapping, said actuators being intended to cooperate thrustingly, in some cases, with the top support members (01, 03) in order to camber the working cylinder (3; 3'; 4; 4') in a first direction and for the remainder with the bottom support members (O2, O4) in order to camber the working cylinder (3; 3'; 4; 4') in the other direction,

   - the hydraulic actuators of the means (10) for applying vertical camber forces on the intermediate cylinders (5, 6) are single-acting actuators disposed in the first and second interspaces of the chocks of the intermediate cylinders, the actuators (V1', V2', V3') disposed in one and the same interspace being overlapping, the actuators being intended to cooperate thrustingly, in some cases, with the top support members (O1', O3') in order to camber the intermediate cylinder in a first direction and for the remainder with the bottom support members (O2', O4') in order to camber the intermediate cylinder in the other direction,
   and in which said rolling mill comprises means for adjusting the axial movement of the intermediate cylinders, and in which these means comprise supports (11, 12, 13, 14) mounted so as to be able slide with respect to the cage, the supports taking the hydraulic actuators (V1', V2', V3') of said means for applying vertical camber forces to the intermediate cylinders (5, 6) so that the axial movement of the intermediate cylinders is obtained without relative movement between the chocks (E2) and said hydraulic actuators (VI, V2, V3).
10. Rolling mill according to claim 9, in which it is possible to keep the same intermediate cylinders (5, 6) when the rolling mill passes from the first configuration (C1) to the second configuration.
11. Rolling mill according to any of claims 9 to 10, in which the rods of the actuators (VI, V2, V3; V1', V2', V3') of said means (9; 10) for applying vertical camber forces to the working cylinders and/or to the intermediate cylinders are intended to be in simple abutment on said support members (O1, O2, O3, O4 ; O1', O2', O3', O4').
12. Rolling mill according to any of claims 9 to 11, in which the chocks (E1, E2) of the working cylinders and of the intermediate cylinders have sliding faces (S) intended to cooperate with guide faces of the cage.
13. Rolling mill according to claim 12, in which the sliding faces (S) of the chocks (E1, E2) of the working cylinders and/or of the intermediate cylinders are situated at the ends of the support members (O1, O2, O3, O4 ; O1', O2', O3', O4').
14. Use of the method according to any of claims 1 to 8 or of the rolling mill according to any of claims 9 to 13, in lines comprising an annealing operation such as for example galvanisation lines or a continuous annealing line, or in rolling mills outside a line, such as for example reversible rolling mills or discontinuous rolling mills on metal strips, for example made from steel, aluminium or bronze.

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