EP0707902B1 - Rolling installation - Google Patents

Description

The subject of the invention is an installation for rolling a flat product such as a metal strip ferrous or non-ferrous and can be applied to rolling hot or cold.

A rolling mill generally includes a set of superimposed cylinders placed inside a fixed support cage having two uprights apart in which openings or "windows" are provided having two vertical parallel sides.

Generally, we pass the product to be laminated, in a longitudinal direction, between two cylinders relatively small diameter work which take support, on the side opposite the product, each on one or several larger diameter support cylinders. The "Quarto" type rolling mills include two cylinders work each associated with a support cylinder. In the "Sexto" type rolling mills, intermediate cylinders are interposed between each working cylinder and the associated support cylinder.

The axes of all the cylinders are placed, normally in the same clamping plane substantially perpendicular to the longitudinal axis of travel of the product and which generally coincides with a plan transverse median of the cage.

Each cylinder is carried by a shaft having two ends rotatably mounted, through bearings, on two chocks strung, respectively in the two windows of the amounts of the cage.

The rolling of the product is carried out by exerting a clamping force applied between the chocks of the support cylinders and transmitted to the product by the working cylinders. Each cylinder must therefore be able move vertically for tightening so that adapt to product thickness and variations in diameter resulting, for example, from wear.

Generally speaking, therefore, chocks of each cylinder have sliding faces cooperating with guide faces provided on both sides of each window.

As the working cylinders have a smaller diameter, the guide faces of their chocks can be closer together and are generally spaced out protruding parts formed in the central part of every window.

However, the cylinders must be capable of being changed either in case of wear or deterioration, or to use cylinders of different diameter. In this indeed, the cylinders can be introduced into the cage or removed from it by sliding, parallel to their axes, on rails fixed on the uprights of the cage and on which the chocks rest, for example by means of rollers. We can also replace the two working cylinders at the same time, the chocks of the upper cylinder resting on the chocks from the lower cylinder which themselves move on fixed rails. The chocks of the cylinders must therefore slide not only vertically, but also horizontally between the guide faces provided on both sides of the window.

To allow the different movements of sliding of the chocks, as well as the installation of cylinders inside the cage or removing them there it is necessary to leave a minimum clearance between the faces side of the chock and the guide faces corresponding.

As a result, we cannot provide perfectly rigorous positioning of the axes of different cylinders and, in particular, their parallelism.

However, during rolling, the working rolls are supported, on one side, on the product being scrolling and, on the other side, on a support cylinder or an intermediate cylinder and it follows that a even very slight misalignment of the axis of a cylinder of work in relation to the scroll direction of the product and to the axis of the corresponding support cylinder can result in an axial displacement effect of the cylinder which is pushed towards one of the uprights of the cage, the associated supporting cylinder being generally subjected to a axial displacement effect in the other direction. The cylinders are retained by axial stops, but there results, however, from friction with an effect hysteresis which can disturb the thickness control normally performed by the clamping system.

Furthermore, as the clamping forces are applied to the ends of the cylinder shafts these may be slightly deformed by bending, especially since the product may have a variable width and therefore does not normally extend over the entire length of the working cylinders. The result that the ends of these tend to get closer together and that the compression force is not distributed equally over the entire width of the product, the lateral edges being more flattened than the central part.

This effect can be offset by giving support cylinders with a curved profile, possibly variable.

But we can also exercise on the ends of working cylinder shafts for bending efforts adjustable so as to correct the profile of the work to compensate for the bending of the support cylinders.

For this purpose, groups of cylinders resting on the chocks to spread them apart each other by achieving a so-called "positive" camber working cylinders.

Often, cylinders acting in the opposite direction, which bear directly on the cage or on the chocks of the support cylinder associated, to bring the two together chocks the working rolls and make a bend says "negative".

In some provisions, arching is performed in both directions by double cylinders effect.

To make up for lateral play and guarantee positioning of the axes of the working cylinders, we have proposed to associate with each chock pushing means side consisting of cylinders or deformable faces arranged on both sides of the chock and taking support horizontally on the cage, each chock being thus secured with the corresponding amount by pushing side on both sides of the window (DE-A-3,807,654).

In a similar arrangement suitable for rolling reversible, it was even planned to increase the play between the chocks of the working rolls and their faces guidance so as to be determined by means of support cylinders lateral, an offset of the line of the axes of the cylinders of work on one side or the other of the line of the axes of support rolls, depending on the direction of rolling (FR-A-1.314.027).

In all cases, the chocks are joined, in service, with the uprights of the cage, by support side on both sides of the window. Therefore, if one wishes to carry out a bending of the cylinders for compensate for bending, this effect should be set to advance, the spacing of the chocks cannot be changed during rolling.

We even proposed, in a provision particular disclosed in document JP-A-61-129208, increase the lateral tightening of chocks in case of spacing of these during rolling.

To this end, each chock is fitted with jacks bending and side jacks whose chambers are interconnected so that an increase in pressure in the direction corresponding to the spacing of chocks determines an increase in the effort of lateral thrust and therefore, blockage of the chock.

However, in recent years, it has become apparent that was very advantageous to use the camber cylinders not only to compensate for the bending of the cylinders support, but also to vary, during rolling, the air gap profile and the distribution of constraints in the transverse direction so as to correct flatness defects detected downstream.

To solve such problems, the invention has subject to a new provision allowing make all the necessary adjustments to achieve rolling in the best conditions, even in progress rolling, immediately correcting any defects detected.

Indeed, the invention makes it possible to control strictly the position and, in particular, the parallelism of the axes of the cylinders, without ceasing to apply corrective efforts to arching one way or the other.

The arrangements according to the invention also allow to bring to the positioning of chocks all the corrections needed to minimize breakouts axial, compensate for the bending of the support cylinders, and correct flatness defects.

In addition, thanks to the great flexibility of adjustment provided by the improved means according to the invention, it is also possible to slightly shift the axes of the support cylinders in relation to the passing clamping plane by the axes of the working cylinders or else to realize a determined intersection of the axes of the different cylinders so as to obtain particular effects.

The invention therefore generally applies to a rolling plant for a flat product comprising a support cage comprising two uprights separated between which at least two are placed stacked working cylinders rotating respectively around axes placed substantially in a clamping plane perpendicular to the direction of travel of the product, and limiting a product air gap, and a cylinder clamping means resting on the cage fixed, each cylinder being carried by a shaft having two ends rotatably mounted, through bearings, respectively on two chocks threaded in two windows respectively in the two cage uprights and sliding mounted along fixed guide faces, parallel to the clamping plane P and provided on both sides of each window, games being left on either side of each chock to allow the assembly and disassembly of each cylinder with its chocks, each chock being associated to lateral thrust means against said faces of guide for taking up, in service, said games.

In accordance with the invention, each chock of a working cylinder is associated with two parts intermediaries interposed respectively between the two sides of chock and guide faces corresponding and on which means are mounted for bending working cylinders supported by the chocks at least in a positive direction of separation said chocks, said intermediate pieces being maintained applied with the possibility of sliding without play, parallel to the clamping plane, respectively along the guide faces window, and pushing means side are interposed between at least one of said intermediate pieces and the corresponding side of the chock so as to rest on the guide face corresponding to push back the chock, on the opposite side, against the other intermediate piece and the other face of guide, the latter constituting a retaining face permanent side for positioning the axis of the cylinder with possibility of sliding the chock with the two associated intermediate parts parallel to said lateral holding face, under the action of the cambering means.

Particularly advantageously, means adjustable thickness retainers are interposed between the minus the intermediate piece placed on the side opposite lateral thrust means and the side facing the chock, said retaining means defining, on each window, a virtual side support side china, the position of which can be adjusted by variation the thickness of said retaining means.

The invention applies especially to a rolling mill quarto type, comprising two working cylinders each associated with at least one support cylinder. In this case, each upright window has two sides flat guide, parallel to the clamping plane and each extending over the entire height of the window, so as to encompass the chocks from all the cylinders these last being associated each with two parts intermediates equipped with sliding retaining means without play along said guide faces and on which are mounted lateral thrust means constituting, on the one hand, a means of application and, the other, an adjustable means of chock retention corresponding.

Preferably, the two intermediate pieces placed on either side of the chock are associated, each with adjustable stroke thrust means interposed respectively between said piece intermediate and the side facing the chock, the pushing means placed on the side of the guide face against which the chock is applied being adjustable in position so as to define a virtual face of lateral support of the chock.

The invention also relates to a method of placing using a rolling mill of this type.

In particular, thanks to such provisions, the rolling mill may be fitted with means for measuring the thrust axial exerted, in one direction or the other, by one either end of a cylinder on the upright cage and the respective positions of holding two virtual faces are determined by adjusting the retaining means, in function of the axial thrust measurement so that determine an orientation of the cylinder axis likely to cancel said measured axial thrust.

In this way, it is possible to define faces virtual holding chocks whose positions can be adjusted to vary the position of the axis of a cylinder in relation to the others, for example to suppress the measured axial force or else cross axes or offset the plane passing through the axes of the working cylinders relative to the plane passing through the axes of the support cylinders.

The invention also covers many particularly advantageous construction arrangements which are the subject of the subclaims.

La Figure 1 est une vue schématique, en élévation, d'un laminoir de type Quarto.

La Figure 2 est une vue de dessus schématique du laminoir, avec arraché partiel.

La Figure 3 est une vue de dessus schématique d'un cylindre de travail muni de ses moyens de réglage d'alignement.

La Figure 4 est une vue en élévation d'un laminoir perfectionné selon l'invention.

La Figure 5 est une vue de détail montrant, en élévation, les empoises de deux cylindres de travail superposés.

La Figure 6 est une vue de dessus, en coupe partielle, selon la ligne AA, de la Figure 5.

La Figure 7 est une vue partielle, en élévation, d'un autre mode de réalisation.

Les Figures 8 et 9 sont, respectivement, une vue de côté et une vue de dessus du mode de réalisation de la Figure 7.

However, the invention will be better understood from the detailed description of several embodiments given by way of example and shown in the accompanying drawings.

Figure 1 is a schematic view in elevation of a Quarto type rolling mill.

Figure 2 is a schematic top view of the rolling mill, partially broken away.

Figure 3 is a schematic top view of a working cylinder provided with its alignment adjustment means.

Figure 4 is an elevational view of an improved rolling mill according to the invention.

Figure 5 is a detail view showing, in elevation, the chocks of two superimposed working rolls.

Figure 6 is a top view, in partial section, along the line AA, of Figure 5.

Figure 7 is a partial view, in elevation, of another embodiment.

Figures 8 and 9 are, respectively, a side view and a top view of the embodiment of Figure 7.

In Figures 1 and 2, there is shown schematically, in elevation, a rolling stand 1 comprising two vertical uprights 11, 11 'apart, fixed on a box spring 10 or, directly, on a massif of foundation, and connected by a 10 'crossbar.

In the example shown, the rolling mill is of the type Quarto and includes two working cylinders 2, 2 ', limiting an air gap in which the product passes to laminate M and taking support, respectively, on the side opposite the product M, each on a support cylinder 3, 3 '.

Each working cylinder 2 is rotatably mounted on a central shaft having two rotating ends 21 respectively in aligned bearings 22 defining the axis of rotation x'x of the cylinder.

The bearings 22 are mounted respectively in support chocks 4 which are inserted in windows 12 respectively provided in the two uprights 11 of cage 1.

Likewise, each support cylinder 3 is mounted rotatable around its axis y'y on a tree whose ends 31 rotate in bearings 32 mounted in chocks 5 threaded into the windows 12, the axes of all the cylinders being placed substantially in the same clamping plane P constituting a median plane of the cage.

The rolling effort is exerted by means of tightening 14 such as screws or jacks, mounted on cage 1 and bearing on the chocks 5 of one of the cylinders support 3.

To allow the cylinders to be tightened, the chocks must be slidably mounted along guide faces parallel to said plane P.

As indicated above, the faces of guide work chocks are usually formed on projecting parts, the cylinders having a smaller diameter.

In the invention, on the other hand, each window 12 of the cage is limited by two flat faces 13a, 13b which extend over the entire height of the window so as to each constitute the same guide face for the chocks of all the cylinders.

In addition, as shown, respectively at left and right of Figure 2, the chocks 4 of working rolls and preferably chocks 5 support cylinders are each placed between two intermediate parts 6a, 6b, respectively 60a, 60b, which are applied and held against the faces of guide 13a, 13b of window 12 with a possibility of sliding without play.

To allow the assembly and disassembly of cylinders, we leave a certain clearance between the faces lateral 41, 51, working chocks 4 and support 5, and, respectively, the lateral faces facing the intermediate parts 6, 60.

As shown schematically on the Figure 2, this game can be canceled by means of thrust 7 interposed between at least one of the parts intermediaries 6b and the face opposite the chock 4 so as to push it towards the guide face opposite 13a which therefore constitutes a retaining face permanent side of the corresponding cylinder 2.

The two side faces 13a, 13'a placed with a same side of plane P on windows 12, 12 'define thus a reference plane P1 for the positioning of x'x and y'y axes of the working cylinders 2, 2 'and support 3, 3 '.

On the other hand, according to another characteristic essential of the invention, the sliding mounting of intermediate pieces 6a, 6b for guiding the chocks 4 working rolls 2 allows to place on them bending cylinders 81 of said cylinders 2 which are associated with oil supply means, the whole constituting a hydraulic camber block which, contrary to the usual arrangements, moves therefore with the chock along the guide faces 13a, 13b.

To allow parts to slide without play intermediate 6 along the guide faces 13, one can use roller or sliding systems, which will be described in more detail below, referring to Figures 5 to 9.

Furthermore, it is particularly advantageous to interpose retaining means of adjustable thickness between each chock 4 and the intermediate piece 6a on which it is applied. To this end, in the mode of realization shown schematically in Figure 3, hydraulic cylinders 70a, 70b are used, placed, respectively, on either side of each chock 4 and which can be adjusted in pressure and position.

The jacks 70b, interposed between each chock 4 and the intermediate piece 6b bear on it and the corresponding side 13b of the window to repel the chock 4 towards the opposite side 13a and therefore constitute the means of application of each chock 4 on the face guide 13a of the upright 11.

The pressure exerted by the jacks 70b is, however, set to be only sufficient to cancel games, but limited enough to avoid a clamping of the chock on the amounts of the cage and thus allow the sliding of the intermediate parts 6a, 6b under the action of the cambering means 8.

On the other side of the chock, the cylinders 70a bearing on the intermediate part 6a, can be adjusted in position so as to constitute a means of adjustable thickness retainer that adjusts the distance between the lateral side 41 of the chock 4 and the guide face 13a.

In this way, the ends of the two jacks 70a facing the chock 4 define a face of virtual holding of the chock whose position can be adjusted by varying the stroke of the cylinders 70a.

So while in the case of Figure 2, each cylinder could be applied against a plane of reference P1 defined by two fixed guide faces 13a, 13'a, it is possible, in the case of Figure 3, to vary one with respect to the other, the positions virtual retaining faces A, A ', with respect to guide faces 13a, 13'a, of the two uprights 11, 11 ', and, therefore, to give the axis x'x of cylinder 2 a specific direction which, if necessary, can be slightly angularly offset from plane P2 passing through the guide faces 13a, 13'a, of the two uprights 11, 11 '.

Thanks to such provisions, it is therefore on the one hand, it is possible to position the axis of each cylinder with respect to a fixed reference plane, or to vary the orientation of the reference plane by according to needs and, on the other hand, to exercise in permanently on the cylinders of the bending efforts positive or negative, both types of adjustment can be performed simultaneously and during rolling.

In Figure 4, there is shown, in elevation, a example of an improved rolling mill according to the invention, in the changing position of the cylinders of job.

The rolling mill is of the "Quarto" type and therefore includes two working cylinders 2, 2 ', associated with two support cylinders 3, 3 ', whose axes are placed substantially in a vertical clamping plane P which constitutes a transverse median plane of the cage 1 of the rolling mill, this comprising two uprights 11, 11 ′, provided with windows 12, 12 ', into which are threaded the chocks of the different cylinders.

The cylinders are tightened by a screw system or jacks 14 supported, in the example shown, on the chocks 5 of the support cylinder upper 3, while the chocks 5 'of the cylinder lower support are supported directly on the box spring 10.

Each chock 4 of a working cylinder 2 is placed between two intermediate parts 6a, 6b, and is provided with two ears 42 on which are supported means for positive or negative cambering of the cylinder. These cambering means are constituted, as usually small cylinders housed, with their supply and discharge pipes, in the intermediate parts 6a, 6b, which thus constitute each a hydraulic camber block.

In the embodiment of Figures 4 and 5, each chock 4 is provided with two ears 42 which playfully engage in notches 62 provided respectively in the central part of each room intermediate 6a, 6b.

Each intermediate piece 6 is provided, on its face side facing the chock, of two pairs of jacks 70 with horizontal axis, placed respectively above and below the notch 62 and bearing on the corresponding side face 41 of the chock 4.

The jacks 70, placed on either side of chickens, act in opposite directions and can therefore be single acting. Supply lines, which have not been shown in Figures 4 and 5, are arranged inside the intermediate parts 6 which thus constitute mobile hydraulic blocks.

As indicated above, the horizontal thrusts exerted by the jacks 70 ensure a joining of each chock 4 with the intermediate pieces 6a, 6b, which surround it and therefore move vertically with the slate by sliding without play, along the faces of guide 13a, 13b, of the window 12.

For this purpose, each intermediate piece 6 is provided on each side with two pairs of rollers 64 which are rotatably mounted around axes parallel to the axis of the cylinder and can roll on the guide faces 13a, 13b, formed along the two lateral sides of the window 12 and parallel to the clamping plane P. Each intermediate piece 6 can be kept applied against the amount 11, for example through hooks sliding in grooves. But we can also mount 64 'auxiliary rollers on each chock associated, respectively, with the rollers 64 of so as to frame the protruding parts 16 formed on the two sides of each guide face 13a, 13b.

The clearance (e) which is left between the lateral sides 41 of each chock and the opposite faces 61 of each piece 6 can be relatively large, so that allow possible adjustments of the orientation of the axis x'x of the cylinder with respect to the guide faces 13.

During the introduction and withdrawal operations of a cylinder, the chocks remain threaded on the pins and move with the cylinder while the intermediate parts 6a, 6b, are kept applied on the guide faces 13 of the cage by the pairs of rollers 64, 64 '.

Since, during bending, the parts intermediaries 6a, 6b, move vertically with chock 4, notches 62 should just be a slightly wider than the ears 42 of the chocks so to simply spare the game necessary for the engagement of ears 42 in the notches 62 during installation of the cylinder with its chocks inside the cage.

The camber cylinders are housed in bores formed on the intermediate parts associated with each work chock (4, 40). Camber cylinders negative (81, 81 ') which are supported, in a conventional manner, on the chocks 5, 50, support cylinders correspondents 3, 3 ', are thus housed in bores 63, 63 ', formed on the external side of each chock of work, respectively upper 4 and lower 40, facing the corresponding support slab 5, 50.

Positive bending is done, in a way known, by cylinders 82 interposed between the two working chocks 4, 40. In the embodiment shown in Figures 4 and 5 by way of example, the positive cambering cylinders 82 are housed in bores 65 arranged on the internal side, facing the upper chock 4, of each intermediate piece 6 ' associated with the lower working chock 40. The rod each cylinder 82 is supported on a pusher 83 which is slidably mounted vertically in a bore 66 crossing the lower part of the intermediate piece 6 of the upper chock 4 and which comes to bear on the corresponding ear 42 to apply it against the upper side of the notch 62 under the action of the cylinder 82, the intermediate piece 6 being held by the negative camber cylinders 81 which bear on the chock 5 of the upper support cylinder 3.

In the lower part, between the notch 62 'and the external side of each intermediate piece 6' associated with the lower chock 40, is slidably mounted a pusher 84 in the form of a jack, coaxial and opposite to the 81 'negative camber cylinder, both chambers cylinders 84, 81 ', communicating with each other. In this way, the pressure applied on cylinder 81 'for bending negative determines the lift of pusher 84 for the application of the ear 42 'against the upper side of the notch 62 'and the take-up of the game.

The two play catch buttons 83, 84, are thus actuated by positive camber cylinders 82 and negative 81, 81 '.

In the service position shown on the Figure 5, the positive 82 and negative camber cylinders 81, 81 ', are put under pressure and push back the pushers 83, 84, which apply each ear 42, 42 ', against the upper face of the corresponding notch 62, 62 '.

In this way, all the games are caught up, each chocks 4, 40, being secured to the blocks hydraulic 6, 6 'corresponding.

It should be noted that the positive cambering cylinders 82 and negative 81, 81 ', as well as the pushers 83, 84, placed on each side of the chock are aligned, respectively, in two directions parallel to the plane P and equidistant from it. In addition, all cylinders are powered at the same time and therefore act in opposite directions by balancing each other.

It is thus possible to carry out a bending positive or negative by simply adjusting the pressures applied on positive camber cylinders 82 or negative 81, 81 'so as to move the chock towards up or down by simply adjusting the pressure difference one way or the other.

Thanks to this arrangement and the sliding mounting hydraulic blocks made up of parts intermediates 6, 6 ', the positive bending efforts or negative close on the cage through the support chocks 5, 5 ', the jacks 14 and the bed base 10.

When setting up the working cylinders, the camber cylinders 81, 81 ′, 82 and, consequently, the pushers 83, 84 are retracted and allow the free sliding of the ears 42 in the notches 62, as shown in Figure 4.

Preferably, place inside the notches 62 sections of rails 43 which extend between the two amounts of the cage and which move with the parts intermediates 6, 6 '.

When the pushers 83, 84 are lowered, the chocks 4, 40 come to rest on said rails 43, 43 ' by means of rollers 44, 44 'rotatably mounted at ends of the ears 42, 42 '.

In the withdrawal position of the work, the 64 'rollers associated with each part intermediate 6a, 6b, come to rest on wedges fixed 67 at a level for which the rail sections 43, 43 'come in the extension of fixed rails 45 shown schematically in Figure 6.

In this position, it is therefore possible to proceed with the assembly or disassembly of the work 2, 2 'whose chocks 4, 4' are carried by the rollers 44, 44 'rolling on the movable rails 43, 43' aligned respectively with the fixed rails.

The support cylinders can be removed analogously, the corresponding intermediate parts 60a, 60b being supported by the cylinders 15, 15 '.

Of course, in the usual case where the camber is made, for each chock, by two pairs of cylinders, respectively arranged on either side of the sponge, we will also use pairs of pushers 83 and 84, so as to associate a pusher with each jack.

The chocks 5, 50, support cylinders 3, 3 ', can be mounted in a conventional way in windows 12, 12 ', from the cage. In this case, the invention applies only at working cylinders 2, 2 '. Given that the horizontal push cylinders 70 are adjustable in position, it is possible, as we have seen, to adjust the positions of the virtual retaining faces to cancel the axial thrusts resulting from a possible offset angle of each working cylinder with respect to its support cylinder.

But it is particularly advantageous to apply also the invention with the support cylinders 3, 3 '.

In this case, as shown in Figure 4, each chock 5, 50 of a support cylinder 3, 3 'is associated with two intermediate parts 60a, 60b, interposed between the lateral faces 51a, 51b, of the chock 5 and the guide faces 13a, 13b, of the upright 11 which extend practically over the entire height of the window 12.

The cage 1 is also provided with two pairs of cylinders 15, 15 'allowing the height adjustment of the support cylinders 3, 3 'while maintaining the two pairs of chocks 5, 50, respectively, against the clamping system 14 and box spring 10.

In the example shown, the chocks 5, 50, two support cylinders 3, 3 ', are each associated with two intermediate pieces 60a, 60b, similar to the pieces intermediaries 6a, 6b, working chocks 4 and on which are articulated the rods of the cylinders of holding 15, 15 '.

In addition, the two intermediate parts 60a, 60b, surrounding each chock 5, 50, are each provided with two projecting parts 65 limiting a recess in which engages with play an ear 52 of the chock 5 to allow height adjustment of the cylinders at by means of the cylinders 15, 15 '.

On the other hand, horizontal thrust cylinders 72 are housed in said projecting parts 65 and are supported on lateral faces 53 of the chock 5, on either side of the ear 52, so as to apply the chock 5 on one of the guide faces 13a taking support on the other face 13b, via parts 60a, 60b.

The cylinders 72 are adjustable in position and therefore allow to define a virtual holding face serving as a reference for positioning, with possibility of sliding, of the y'y axis of the cylinder support 3.

This provides flexible and precise means for maintain the alignment of the axis of each cylinder by compared to a reference plane and to adjust possibly the positioning of the cylinders compared to others.

In particular, this positioning can be adjusted as a function of the axial force detected at the end of a cylinder. For example, if an axial force is detected exercised by a working cylinder on one side of the cage, the chocks for positioning the chock of the cylinder placed on the same side to move the axis in the opposite direction to rolling and we act in the opposite direction on the corresponding support cylinder, so as to cancel the axial force detected, the directions of action being reversed, for each of the two cylinders, on the other side of the cage.

But we can also act differently on chocks, for example to move the clamping plane passing through the axes of the working cylinders relative on the plane passing through the axes of the support cylinders, to adjust the alignment of a working cylinder-cylinder assembly support in relation to each other or else cross the clamping planes of the two sets.

We therefore see that the invention has multiple possibilities and is not limited only to the details of the embodiment which has been described as a simple example and to which we could make variants without deviate from the protective framework defined by claims.

In particular, the rolling bearings of the parts intermediaries can be replaced by simple smooth, smooth sliding bearings, as shown in Figures 7, 8, 9.

As seen in Figures 8 and 9 each intermediate piece 6 includes a sliding face 68 along the lateral face 13 of the upright 11, means lubrication not shown to ensure a soft glide.

Side hooks 69 surround parts in projection 16 formed on either side of the face of guide 13 to maintain the latter against the intermediate piece 6.

As before, in the withdrawal position of the cylinder, the hooks 69 come to rest on shims fixtures 67a shown schematically in Figure 8.

In addition, other provisions could be used for positive or negative arching of cylinders and, for example, the support ears provided on either side of each chock can, so known, extend above or below the block hydraulic.

In general, the invention does not requires only fairly minor modifications to the cage and can therefore be easily adapted to any existing type of rolling mill. In particular, the arrangements described in as an example in the case of a Quarto rolling mill can be used in a Sexto rolling mill with intermediate cylinders interposed between each cylinder working and the support cylinder, or even in case each working cylinder is supported by a set of cylinders arranged on either side of the median plane.

The reference signs inserted after the technical characteristics mentioned in the claims are intended only to facilitate the understanding and limiting them in no way the scope.

Claims (23)

1. Rolling mill for rolling a flat product running in a longitudinal direction, comprising a fixed support stand (1) which includes two spaced-apart uprights (11, 11') between which are placed at least two superposed work rolls (2, 2') which rotate respectively about axes lying substantially in a clamping plane (P) perpendicular to the direction in which the product (M) runs, and delimiting a gap for passage of the product (M), and a means (14) for clamping the rolls bearing on the fixed stand (1), each roll (2, 2') being supported by a shaft which has two ends mounted so as to rotate, by means of bearings, respectively on two chocks (4, 40) slipped into two windows (12) which are provided respectively in the two uprights (11, 11') of the stand and are mounted so as to slide along fixed guide faces (13a, 13b), these being parallel to the clamping plane (P) and provided on the two sides of each window (12), clearances being left on either side of each chock (4) in order to allow assembly and dismantling of each roll (2) with its chocks (4, 4'), each chock being associated with means (7) for thrusting laterally against the said guide faces (13a, 13b) in order to take up, in service, the said clearances, each chock (4, 40) of a work roll(2, 2')being associated with two intermediate pieces (6a, 6b) interposed respectively between the two sides of the chock (4) and the corresponding guide faces (13a, 13b) and on which are mounted means (81, 81', 82-84) for cambering the work rolls, characterized in that the means (81, 81', 82-84) for cambering the work rolls bear on the chocks (4, 40) at least in one positive direction of separation of the said chocks (4, 40), in that the said intermediate pieces (6a, 6b) are held pressed, with the possibility of sliding without any clearance, in a manner parallel to the clamping plane (P), respectively along the corresponding guide faces (13a, 13b) of the window (12), and in that lateral thrust means (7) are interposed between at least one (6b) of the said intermediate pieces and the corresponding side of the chock (4) so as to bear on the corresponding guide face (13b) in order to push back the chock (4), on the opposite side, against the other intermediate piece (6a) and the other guide face (13a), the latter forming a permanent lateral holding face for the positioning of the axis (x'x) of the roll with the possibility of the chock (4) with the two associated intermediate pieces (6a, 6b) sliding in a manner parallel to the said lateral holding face (13a), under the action of the cambering means (81, 81', 82-84).
2. Rolling mill according to Claim 1, characterized in that adjustable-thickness retaining means (70a) are interposed between at least the intermediate piece (13a) placed on the opposite side to the lateral thrust means (7) and the side (41a) facing the chock (4), the said retaining means (70a) defining, on each window (12), a virtual lateral holding face (AA') for the chock (4), the position of which can be adjusted by varying the thickness of the said retaining means (70a).
3. Rolling mill according to Claim 2, characterized in that the retaining means consist of adjustable-travel thrust means (70) acting in a direction perpendicular to the corresponding guide face (13) band bearing in one direction on the chock (4) and in the opposite direction on the corresponding intermediate piece (6).
4. Rolling mill according to Claim 3, characterized in that the two intermediate pieces (6a, 6b) placed on either side of the chock (4) are each associated with adjustable-travel thrust means (70a, 70b) interposed respectively between the said intermediate piece (6a, 6b) and the side (41a, 41b) facing the chock (4), the thrust means (70a) placed on the side of the guide face (13a) against which the chock (4) is pressed being positionally adjustable so as to define a virtual lateral holding face for the chock (4).
5. Rolling mill according to one of Claims 2 to 4, characterized in that it comprises means for measuring the axial thrust exerted, in one direction or the other, by one or other of the ends of a roll on the corresponding upright (11) of the stand (1) and in that the respective positions of the virtual holding faces for the two chocks are determined by adjusting the retaining means (70a), depending on the measurement of the axial thrust so as to determine an orientation of the axis (x'x) of the roll (2) with which the said measured axial thrust is able to be cancelled.
6. Rolling mill according to one of the preceding claims, comprising two work rolls (2, 2') each associated with at least one back-up roll (3, 3'), characterized in that each window (12) in an upright (11) is provided with two plane guide faces (13a, 13b), these being parallel to the clamping plane (P) and each extending over the entire height of the window (12), so as to incorporate the chocks (4, 40) (5, 50) of all of the rolls (2, 2') (3, 3'), these chocks each being associated with two intermediate pieces (6a, 6b) (60a, 60b) equipped with holding means sliding without any clearance (64) along the said guide faces (13a, 13b) and on which are mounted lateral thrust means (70) forming, on the one hand, a means of application (70b) and, on the other hand, an adjustable retaining means (70a) for the corresponding chock (4, 40) (5, 50).
7. Rolling mill according to Claim 6, characterized in that the two guide faces (13a, 13'a) against which the two chocks (4, 4') (5, 5') of each roll (2, 3) are pressed are placed on the same side of the clamping plane (P) and define a fixed reference plane (P1) for the positioning of the axis (x'x, y'y) of the roll (2, 3).
8. Rolling mill according to one of the preceding claims, characterized in that the holding means sliding without any clearance of each intermediate piece (6, 60) comprise at least two rollers (64) for bearing on the corresponding guide face (13), the said rollers being placed on two levels spaced apart vertically and being mounted so as to rotate about axes parallel to the axis of the roll (2, 3), the said bearing rollers (64) being associated with holding rollers (64') rolling on opposite faces of projecting parts (16) provided respectively on the two sides of each guide face (13).
9. Rolling mill according to one of Claims 1 to 8, characterized in that the sliding holding means of each intermediate piece (6, 60) consist of a slideway (9) having at least one sliding bearing face (91) which is provided on that side of the intermediate piece (6, 60) turned towards the corresponding guide face (13) and is associated with means for forming a lubricating film, the said intermediate piece (6, 60) being provided with two hook-forming pieces (92) surrounding two projecting parts (16) provided respectively on the two sides of each guide face (13) for holding the intermediate piece (6, 60).
10. Rolling mill according to one of the preceding claims, characterized in that each chock (4, 5) of a roll (2, 3) is provided, on its two sides, respectively, with two lateral lugs (42, 52) engaging with clearance in notches (62, 53) which are provided, respectively, on the two intermediate pieces (6, 60) associated with the chock (4, 5) so as to allow the roll (2, 3) to be dismantled with these chocks (4, 5), the guide pieces (6, 60) remaining rigidly fastened to the stand (1).
11. Rolling mill according to Claim 10, characterized in that the two intermediate pieces (6a, 6b) flanking each chock (4) of a work roll (2) are provided with removable means for rigidly fastening the said intermediate piece to the corresponding lug (42) of the chock (4) by taking up the clearance in the notch (62).
12. Rolling mill according to Claim 11, characterized in that the means for taking up clearance are pushers (83, 84) mounted so as to slide, respectively, in the intermediate pieces (6, 6') which are associated, respectively, with the chocks (4, 40) of the two work rolls (2, 2') and are actuated, in service, by the cambering means (8) in the direction of application of the corresponding lug (42) of each chock against the opposite side of the corresponding notch (62).
13. Rolling mill according to Claim 12, characterized in that the intermediate pieces (6, 6') associated respectively with the chocks (4, 40) of the two work rolls (2, 2') support negative cambering rams (81) bearing, in one direction on the intermediate piece (6, 6') and in the other direction on the chocks (5, 50) of the corresponding back-up roll so as to determine the extent to which the chocks (4, 40) of the two work rolls (2, 2') move towards each other.
14. Rolling mill according to Claim 13, characterized in that the positive cambering means consist of rams (82) housed in the intermediate pieces (6') associated with the chocks (40) of a first work roll (2') and bearing, in the positive direction of separation of the chocks (4, 40), on a pusher (83) mounted so as to slide in the chock (4) facing the second work roll (2) and itself bearing on the corresponding lug (42), and the intermediate pieces (6'a, 6'b) associated with each chock (40) of the first work roll (2') are provided with pushers (84) actuated by the negative cambering rams (81') of the said chock (40) and bearing on the lugs (42') of the latter in order to take up the clearance in the notch (62').
15. Rolling mill according to Claim 14, characterized in that the positive (82) and negative (81, 81') cambering rams are actuated simultaneously and in that, after the clearances in the notches (62, 53) have been taken up, the positive or negative cambering effect is determined, in service, by adjusting the difference in supply pressures between the positive cambering rams (82) and the negative cambering rams (81, 81'), the intermediate pieces (6, 6') associated with the chocks (4, 40) of the work rolls (2, 2') sliding freely and the intermediate pieces (60, 60') associated with the chocks (5, 50) of the back-up rolls (3, 3') bearing on the stand in such a way that the cambering forces close up on the latter.
16. Rolling mill according to Claim 15, characterized in that the positive cambering rams (82), the two pushers (83, 84) and the negative cambering rams (81, 81') placed on each side of the clamping plane (P) are aligned, respectively, along two axes which are symmetrical with respect to the said clamping plane (P).
17. Process for rolling a flat product running in a longitudinal direction in a rolling mill according to claim 1, characterized in that at least the chocks of each work roll (2) are associated with intermediate pieces (6) interposed between the sides of the chock (4) and the guide faces (13a, 13b), in that the said lateral thrust means (7) bear on at least one of the said intermediate pieces (6b) in order to push back the chock towards the other intermediate piece (6a) and the corresponding guide face (13a), and in that the said intermediate pieces (6a, 6b) are rigidly fastened vertically to the chock (4) and are held with the possibility of sliding without any clearance along the said guide faces (13a, 13b) so as to move vertically with the chock (4) under the effect of a force for cambering the roll (2).
18. Rolling process according to Claim 17, characterized in that retaining means (70) are interposed between the side of the chock (4) placed on the opposite side to the lateral thrust force and the corresponding intermediate piece (6a), the thickness of said retaining means (70) being adjusted so as to define a virtual laterals holding face for the positioning of the axis of the roll (2).
19. Rolling process according to Claim 18, characterized in that the axial force exerted by a roll on one side of the stand is measured and in that the positioning of the axis of the cylinder is varied by adjusting the retaining means (70) so as to cancel out the axial force detected.
20. Rolling process according to Claim 18, in a rolling mill comprising two work rolls (2, 2') each bearing on at least one back-up roll (3, 3'), characterized in that the axial force exerted by each work roll on one or other of the uprights of the stand of the rolling mill is measured and in that the relative positioning of the axes of each work roll (2) and of the corresponding back-up roll (3) is varied so as to allow cancellation of the axial force detected.
21. Process according to Claim 18, in a rolling mill comprising two work rolls (2, 2') each associated with at least one back-up roll (3, 3'), characterized in that the means (70) for retaining the chocks of at least one of the rolls is adjusted so as to determine a crossing of the axis of one work roll (2) with respect to the axis of the corresponding back-up roll (3).
22. Process according to Claim 18, in a rolling mill comprising two work rolls (2, 2') each associated with at least one back-up roll (3, 3'), characterized in that the means (70) for retaining the chocks of at least one of the rolls is adjusted so as to modify the angular position of the assembly formed by a work roll (2) and the corresponding back-up roll or rolls (3) with respect to the assembly formed by the other work roll (2') and the corresponding back-up roll or rolls (3').
23. Process according to Claim 18, in a rolling mill comprising two work rolls (2, 2') each associated with at least one back-up roll (3, 3'), characterized in that the means (70) for retaining the chocks of at least one of the rolls is adjusted so as to modify the position of the clamping plane passing through the axes of the two work rolls (2, 2') with respect to the plane passing through the axes of the back-up rolls (3, 3').

Images