EP2542360B1 - Roll stand - Google Patents

Description

The present invention relates to a rolling stand that can equip a rolling installation, according to the preambles of claims 1 and 15, which are based on the document WO 2004/052568 .

The present invention relates in particular to the field of rolling metal strips, especially special steels such as stainless steels, using a rolling installation generally comprising at least one rolling stand. More particularly, the present invention relates to a rolling stand of said rolling installation and its operation, said cage being intended for rolling any type of metal, and in particular for rolling stainless steels.

Conventionally, a rolling stand is equipped with two vertically superposed working rolls, each having their longitudinal axis of rotation parallel to the running plane of the metal strip and placed in the same clamping plane substantially perpendicular to the running direction of the band between said working rolls. During rolling, the working rolls are generally pressed against each other by a pair of support rollers each having their longitudinal axis in said same clamping plane (or in the vicinity of said clamping plane), and between which is applied pressure - or effort - rolling. Such a rolling plant comprising a rolling stand formed of four vertically superimposed rolls, or two small diameter working rolls pressed against each other by two larger diameter bearing rolls, is called "quarto". ". If another support cylinder, hereinafter referred to as the intermediate cylinder, is interposed between each of the pairs formed by the working roll and the support roll located on the same side of the strip to be rolled, the roll stand is then formed of six cylinders superimposed vertically one above the other, ie a pair of working rolls enclosing the strip to be rolled, framed by a first pair of rolls formed by the intermediate rolls, themselves framed by a second pair of rolls formed by the support rolls. A rolling mill characterized by such a roll arrangement is usually referred to as "sexto" or "6-high". Finally, a roll stand of a sexto-type rolling mill may comprise lateral supports of the working rolls. In particular, each of the working cylinders is in contact on both sides of the clamping plane with a lateral support member, comprising for example a lateral support cylinder itself supported laterally by two rows of support rollers. side mounted side by side. The sexto rolling mills comprising said lateral support members are generally referred to as laterally supported sexto-type rolling mills. In all cases, the cylinders bear against each other along substantially parallel bearing lines and directed along a generatrix whose profile, normally rectilinear, depends on the forces applied and the strength of the cylinders.

Laterally supported sexto-type rolling cages are known to those skilled in the art and are in particular the subject of US Pat. US 4,270,377 and US 4,531,394 . The justification for this particular arrangement of the various cylinders and rollers lies in the adaptation of the diameter of the working rolls to the resistance to plastic flow of the metal to be rolled. Indeed, working cylinders of large diameters, such as those equipping quarto-type cages, induce, with equal thickness reduction, an important contact arc with the band and therefore a greater rolling force with smaller diameter cylinders. For steels having a moderate resistance to plastic flow, it is preferred quarto rolling mills whose large working rolls facilitate the stability of the rolling operation and which wear out less quickly. But for some steels such as stainless steels or other high tensile steels, the choice of small diameter work rolls is necessary in order to maintain reasonable rolling forces. For this reason, sexto-type rolling mills with small-diameter working rolls are used, and when the hardness of the metal to be rolled requires it, it is necessary to use working rolls of very small diameter which bending problems during rolling.

Indeed, the diameter of these working rolls is such that it is impossible to drive them directly, as is usual for cylinders of larger diameter, for example using extensions transmitting at one of their ends the rolling torque from a motorcycle gearbox assembly. The transmission of the torque is then ensured, in the case of these small diameter working rolls, by friction on the intermediate rolls which are themselves driven by a gear motor assembly. This friction transmission generates between the working cylinder and the intermediate cylinder a tangential force proportional to the transmitted torque. In the case of rolls of very small diameter, this tangential force causes a longitudinal bending of the working roll leading to defects in the flatness of the rolled strip.

In order to avoid this harmful flexion, and as described in the patents US 4,270,377 and US 4,531,394 , each work roll is supported, at least on the side of the entrance of the band in the grip of the working cylinders, by a lateral support cylinder, itself supported by two rows of rollers, lateral support cylinder and rollers being fixed on support arms whose position is adjustable in order to adapt to different diameters of new or worn work rolls. Generally, each of the working rolls is supported laterally by a pair of lateral support rollers located on either side of the clamping plane, each of them being supported by said two rows of rollers.

The patent US 4,270,377 describes for example a rolling stand comprising two working rolls, each being supported on the one hand vertically by an intermediate roll itself supported by a support roll, and also, on the other hand, laterally by two support rolls lateral supported themselves by two rows of support rollers. In the embodiment disclosed by the aforementioned patent, the working rolls are not supported and held in place by means of chocks, but are simply held axially by two axial roller stops. In addition, each lateral support cylinder and its two rows of rollers are carried by a support arm articulated on a chock of the support cylinder and have a displacement member radial with respect to the working cylinder. The chocks of the intermediate rollers are furthermore equipped with jacks intended to provide a camber of said work rolls. They are also equipped with special bearings without inner ring and cylindrical roller, which allow the intermediate cylinders to move axially under the action of an axial displacement member mounted in one of the two chocks of each intermediate cylinder. Said axial displacement corresponds to a displacement of said intermediate cylinder along its longitudinal axis of rotation. Camber and axial displacement of the intermediate cylinders being, in known manner, used to improve the flatness of the rolled metal strips.

The very small diameter of the working cylinders imposes very small values of diameters of the intermediate rolls. The patent US 4,270,377 for example, an intermediate cylinder diameter of 6 inches for a working cylinder of 2.25 inches. It follows that the chocks of intermediate rolls are of reduced dimensions, which complicates the choice of a bearing capable of supporting the service loads and ensure, at the same time, a sliding relative to the trunnion of the intermediate cylinder.

An improvement of a rolling stand as described in the patent US 4,270,377 is revealed in patents US 4,531,394 and EP 0 937 517 . These describe a rolling stand for which each side support cylinder and its two rows of rollers are carried by a support arm articulated on the chock of the intermediate cylinder. The patent EP 0 937 517 further discloses a cassette comprising an intermediate cylinder, its chocks and two lateral support cylinders respectively supported by two rows of rollers. In this case, an axial displacement system by means of hydraulic cylinders allows axial movement of the intermediate cylinder. Each intermediate cylinder comprises two cylindrical roller bearings without inner ring mounted in two chocks and in which its trunnions can slide axially. Finally, a third chock comprises an assembly of axially fixed bearings on the end of the intermediate cylinder and which both ensures the recovery of the axial forces and the transmission of the axial movement to the intermediate cylinder.

The type of installation described above, and mounting variants of the intermediate cylinders and lateral support in derived from it as described in WO 2004/052568 , have a number of disadvantages, including disadvantages related to the joining of the lateral support cylinders and their two rows of rollers with the chocks of the intermediate rolls or support rollers. This results in particular a complication of the operations of extraction of the intermediate rolls out of the roll stand, as well as a complication of their re-conditioning by rectification of their active surface.

Indeed, according to a widespread and proven technique, the intermediate cylinders can be ground with their chocks still mounted, which has the advantage of avoiding unnecessary disassembly times. In the case of intermediate cylinders secured to their lateral support members (ie each lateral support member, comprising for example a lateral support cylinder and its support rollers, is secured to the intermediate cylinder, or a support of said intermediate cylinder, for example the chocks of said intermediate cylinder), the rectification of the intermediate cylinders with their chocks still mounted becomes impossible and accordingly, it is necessary to disassemble all the crews formed of the intermediate cylinder and its lateral support members at each rectification.

On the other hand all the handling of said crews require, particularly when it comes to return, specific tools preventing inadvertent and dangerous movements of support cylinders and side support rollers.

Finally, it is necessary to park as many complete crews as there are intermediate cylinders to ensure a rotation of said crews without loss of time between the assembly phase of the crew in rolling cage and the maintenance phase of the crew in the workshop. This results in an increase in the cost of the fleet of operational spare parts, in particular, the different crews, as well as an increase of a rotation time between said phases of assembly and maintenance resulting in particular from the need to disassemble all the component parts of said crews.

Another disadvantage results from the operating mode of the previously described rolling stands. Indeed, according to a first mode of operation as described in WO 2004/052568 the axial displacement of the intermediate rollers is ensured by axial sliding of the chocks, which causes a relative movement of the lateral support members with respect to the working rolls with the creation of axial thrusts able on the one hand to damage the axial stops of the said working rolls, and secondly, to degrade the surface of said work rolls by friction on the lateral support members. In addition, according to a second mode of operation of rolling stands described in the prior art, in particular by US 4,270,377 the axial displacement of the intermediate cylinders is ensured by axial sliding of their journals relative to their chocks and therefore, with respect to their bearings. This latter mode of operation has the advantage of keeping the chocks of the intermediate cylinders axially fixed and of preventing any movement of the lateral support members which are fixed thereto with respect to the working rolls during axial displacement of the intermediate rolls, however, this second mode of operation has many disadvantages.

In particular, the choice of bearings without inner ring, characterized by cylindrical rollers rolling directly on the journals of the intermediate cylinders, imposes particularly hard pins and difficult to achieve. On the other hand, said pins have a high risk of damage in service due to wear or peeling under the pressure of the cylindrical rollers with a corresponding decrease in the service life of the intermediate rolls. In addition, it is very difficult to ensure a good seal of such bearings, which can lead to the use of rolling fluids, such as mineral oil, compatible with the lubrication and the absence of corrosion bearings, while other fluids, such as emulsions, would be more suitable for the needs of rolling. Finally, the intermediate cylinders must on the other hand be extended by the axial displacement distance of the intermediate cylinder, which increases the cost of supply of the intermediate cylinder park. On the other hand, such cages sometimes require the use of a third chock. This third chock, equipped with bearing assemblies capable of taking up axial forces, generates additional costs resulting from the need to have even longer cylinders as well as chocks and additional bearings.

In order to solve these problems, another configuration of a rolling stand has been proposed, characterized in particular by a joining of the lateral support rollers and their two rows of rollers, no longer with the chocks of the intermediate rolls or the rolls of the rollers. support, but with the amounts of the rolling stand. Such a configuration is in particular described in the patents WO 01/21334 or WO 2004/041456 of the applicant. According to this configuration, the intermediate cylinders can be easily extracted from the rolling stand and their maintenance can be carried out in a conventional manner, ie without special tools and without dismantling the chocks of the intermediate rolls. However, it also has certain disadvantages in terms of the kinematics of the rolling stand.

A first drawback is interference between the working roll and the two lateral support rolls of the lateral support members during an opening of the roll stand and the subsequent vertical movement of the work rolls. Indeed, the general arrangement of the working cylinders and lateral support means that in the working position, the axes of rotation of the upper lateral support cylinders are located above the axis of rotation of the upper work roll and that the distance between the two lateral support cylinders, when in contact with the working cylinder, does not allow the passage of the working roll upwards, ie in the direction of the upper support roll. The term "superior" refers to rolls or rolling mill devices located above the plane of travel of the strip to be rolled, as opposed to "lower" which qualifies rolls or roll stand members located at below the scrolling plane of the strip to be rolled. Any upward vertical movement of the upper work roll can therefore be hampered by the presence of the two upper side support rollers which do not accompany the vertical movement of the upper work roll. Or, conversely, said vertical movement can be done with lateral support cylinders too far apart not ensuring the lateral stability of the working cylinder. The situation is reversed for the lower work and side support rolls, i.e. located below the running plane of the web in the work roll right-of-way.

Before any vertical movement of the working rolls, it is therefore necessary for the two lateral support rollers to be swept apart from the work roll by a distance sufficient to avoid hindering a vertical displacement of the work roll, while guaranteeing stability side of said work roll. This spacing is achieved either by an operator, which is not reliable, or automatically, which is not guaranteed in the event of a malfunction of a control system of the rolling plant ensuring this automation.

A second disadvantage is interference between the working roll and the two lateral support cylinders of the lateral support members during closure of the cage and the subsequent vertical movement of the working rolls. The interference between the working cylinder and the lateral support cylinders results, for example, from a bad positioning of the lateral support rollers during the maintenance of the rolling stand by an operator (position of the lateral support cylinders too closed with respect to at the position of the working cylinder) or the installation of a new working cylinder whose diameter is greater than the diameter of the working cylinder which has been replaced, or a malfunction of the rolling stand or of positioning errors of the cylinders. In any case, there will be interference between the working cylinder and the lateral support cylinders when closing the rolling stand.

Finally, a third disadvantage is possible interference between the intermediate cylinder and the lateral support cylinders during malfunctions of the control system.

• d'éviter des mouvements axiaux relatifs entre les cylindres de travail et leurs organes d'appuis latéraux durant des opérations de déplacement axial des cylindres intermédiaires, et donc d'éviter des efforts axiaux sur des butées axiales des cylindres de travail et des dégradations de surface desdits cylindres;
• d'éviter des interférences entre cylindres de travail, organes d'appuis latéraux et cylindres intermédiaires, lesdites interférences étant associées aux déplacements verticaux des cylindres de travail et des cylindres d'appuis latéraux durant les phases d'ouverture de la cage de laminage en position d'attente et de fermeture en position de travail.

An object of the present invention is to provide a rolling stand and a method of operating a rolling stand to solve the problems mentioned above. It is in particular to propose a laterally supported sexto-type rolling stand, comprising intermediate cylinders able to be moved axially, ie along their longitudinal axis of rotation, and to be subjected to forces of bending applied by bending blocks, and which would allow:

• to avoid relative axial movements between the working rolls and their lateral support members during operations of axial displacement of the intermediate rolls, and thus to avoid axial forces on axial stops of the work rolls and surface degradations said cylinders;
• to avoid interference between working rolls, lateral support members and intermediate rolls, said interferences being associated with the vertical displacements of the working rolls and the lateral support rolls during the opening phases of the roll stand in position waiting and closing in working position.

For this purpose, a rolling stand and method of operating a rolling stand are provided by the contents of claims 1 and 15. A set of subclaims also has advantages of the invention.

From a rolling stand of a strip to be rolled, said rolling stand comprising two working rolls capable of clamping said strip to be rolled, more specifically, an upper working roll situated above a scrolling plane of the strip to be rolled, and a lower working cylinder located below said plane of travel of the strip to be rolled, the upper and lower working rolls having their longitudinal axes of rotation in a clamping plane substantially perpendicular to the plane of scrolling of the strip to be rolled, two intermediate rolls, respectively an upper intermediate roll adapted to be in contact with the upper work roll and a lower intermediate roll capable of being in contact with the roll lower working cylinder, two support cylinders, respectively an upper support cylinder adapted to be in contact with the upper intermediate cylinder, and a lower support cylinder adapted to be in contact with the lower intermediate cylinder, the cylinders of upper and lower support being adapted to transmit a clamping force to the work rolls via the intermediate rolls, or in other words, the rolling stand comprises six vertically stacked rolls in a sextile rolling stand configuration, further comprising at least one lateral support member capable of laterally supporting one of said working rolls, in particular a first and a second upper lateral support member respectively situated on either side of said clamping plane and able to support said roll laterally; of upper work, and a first and a second lower support member, located on either side of said plane of e clamping and able to support laterally the lower work roll, the rolling stand according to the invention is characterized in that it comprises at least one bending block intended for the bending of said intermediate rolls, said bending block being suitable for being moved vertically relative to the amounts of the rolling stand and to support said lateral support member.

• premièrement, un maintien fixe de l'organe d'appui latéral par rapport au cylindre de travail apte à être soutenu par ledit organe d'appui latéral, lors d'un déplacement axial du cylindre intermédiaire, ledit cylindre intermédiaire étant apte à être en contact avec ledit cylindre de travail apte à être soutenu par ledit organe d'appui latéral;
• deuxièmement, un maintien fixe de l'organe d'appui latéral par rapport au cylindre intermédiaire lors de ses mouvements verticaux, ledit cylindre intermédiaire étant apte à être en contact avec le cylindre de travail apte à être soutenu par ledit organe d'appui latéral;
• et troisièmement, un maintien fixe de l'organe d'appui latéral par rapport à la cage de laminage lors d'un démontage desdits cylindres intermédiaires.

From an operating method of a roll rolling stand, said roll stand comprising two work rolls capable of clamping said rolling strip, two intermediate rolls, two support rolls, or otherwise said six cylinders superimposed vertically in a configuration of rolling cage sexto, further comprising at least one lateral support member adapted to laterally support one of said working rolls, the operating method of the rolling stand according to the invention is characterized by an adjustable positioning of the lateral support member allowing:

• firstly, a fixed support of the lateral support member relative to the working roll adapted to be supported by said lateral support member, during an axial displacement of the intermediate roll, said intermediate roll being adapted to be in contact with with said working cylinder adapted to be supported by said lateral support member;
• secondly, a fixed support of the lateral support member relative to the intermediate cylinder during its vertical movements, said intermediate cylinder being adapted to be in contact with the working cylinder adapted to be supported by said lateral support member;
• and third, a fixed retention of the lateral support member relative to the rolling stand during disassembly of said intermediate rolls.

The rolling stand comprises in particular at least two uprights able to provide vertical guidance of the support cylinders and the intermediate rolls, said two amounts being in particular not intended to directly or indirectly support the intermediate rolls and / or the lateral supports, but only to guide the support cylinders and the intermediate cylinders in a substantially vertical plane (ie substantially perpendicular to the strip of travel).

In addition, said bending block of the rolling stand according to the invention comprises in particular a guiding device, integral with said bending block, and adapted to support and guide said lateral support member. In particular, each of the bending blocks of said rolling stand is capable of including said guide device able to guide and serve as a support for at least one of said lateral support members, so that, for example, blocks of bending supporting a same lateral support member each comprise said guide device, the latter being adapted to guide and support for example a support arm of said lateral support member. In addition, the guide device according to the invention allows in particular a pivoting about an axis of rotation of said guide device, or a sliding along a path pre-defined by said guide device, said lateral support member. Thus, said lateral support member is in particular adapted to pivot about an axis of rotation of said guide device integral with said bending block, or to slide along a path defined by the guide device. In addition, each bending block of the rolling stand according to the invention is able to support at least one chock of an intermediate roll, and an axial displacement thereof. In particular, it is not only suitable for supporting said chock, but it is also intended to support an axial displacement, for example by sliding, of said chock.

In addition, the rolling stand is in particular advantageously characterized by actuators capable of vertically displacing said bending blocks. Indeed, each bending block of the rolling stand according to the invention is in particular adapted to be moved vertically by means of at least one of said actuators. According to a particular configuration, eight bending blocks separated from one another, for example hydraulic bending blocks, are able to support the chocks of the upper and lower intermediate rolls, respectively four upper bending blocks capable of supporting the chocks of the intermediate roll. upper and four lower bending blocks adapted to support the chocks of the lower intermediate cylinder. Of the four upper bending blocks, two bending blocks located at one end of the intermediate cylinder, on either side of said clamping plane, are suitable to serve as support for a chock of said intermediate cylinder, and the other two bending blocks located at the other end of said intermediate cylinder, on either side of said clamping plane, are able to serve as a support for another chock of said intermediate cylinder. Similarly, the four lower blocking blocks are able to serve as support, by pair of two bending blocks, each to a chock of the lower intermediate cylinder. The eight bending blocks are advantageously displaceable vertically with respect to the amounts of the rolling stand, synchronized in groups of four, in particular a first group of four synchronized upper blocks and a second group of four synchronized lower blocks are each movable vertically. , synchronously, by means of at least one actuator, for example a mechanical or hydraulic actuator, in particular adapted to be disposed between an upper bending block and a lower bending block. Thus, at least one actuator is advantageously able to vertically move an upper bending block with respect to a lower bending block, said upper and lower bending blocks being arranged on both sides of the tape running plane and close. at the same end of a working cylinder.

According to an advantageous characteristic of the rolling stand according to the invention, each intermediate roll chock comprises in particular two protuberances intended to slide axially with a slight clearance in choke guide housings arranged in each of the bending blocks. Said protuberances are for example each located on a lateral face of the chock so that the latter is able to be supported by the bending blocks located on either side of the clamping plane. Advantageously, said protuberances are capable of rendering the slidable chock in said chocks of blocks bending in a direction parallel to the longitudinal axis of rotation of the intermediate cylinder. In particular, axial displacement members are able to axially move said intermediate cylinders by displacement of the chocks of said intermediate rolls with respect to the bending blocks. Thus, the rolling stand according to the invention is characterized by a device for carrying an intermediate roll comprising an axially fixed portion relative to the roll stand, namely the bending blocks, and an axially movable part with respect to said rolling stand. rolling stand, namely the chocks of each of said intermediate rolls.

Each of the upper and lower working cylinders can therefore be supported / supported laterally, on either side of the clamping plane, by lateral support members that are adjustable in position but axially fixed with respect to the rolling stand (the term axially referring to the axial direction defined by the longitudinal axis of rotation of the working or intermediate rolls).

Advantageously, the constructive arrangements described above allow the guiding devices of the lateral support members to remain axially fixed with respect to the working rolls during axial displacement of the intermediate rolls, or more precisely, during axial displacement of the chocks supporting a intermediate cylinder. Indeed, each of the working rolls does not comprise a chock, but is stopped axially at each of its ends by axial stops able to maintain said working roll in an axially constant or fixed position relative to the roll stand during rolling a strip to be rolled. The bending blocks, integral with the guide devices of the lateral support members that they support, are axially fixed relative to the same cage. he As a result, with close functional play, in particular gaps between the ends of the working rolls and their axial stops, the lateral support members are able to remain axially fixed with respect to the working rolls during rolling. This axial fixity does not prevent each of the lateral support members from moving radially relative to the working rolls, in particular by sliding in slide-type guiding devices, or by pivoting around a center or axis of rotation. a rotary type guiding device. In other words, the lateral support members are able to move in directions lying in a plane substantially perpendicular to the plane of travel of the strip to be rolled and substantially perpendicular to the axial direction defined by a longitudinal axis of rotation of the strip. an intermediate or working cylinder.

Advantageously, these same constructive arrangements also allow the guiding devices of the lateral support members to remain fixed with respect to the intermediate cylinders during a vertical displacement thereof, since during a vertical displacement of a block bending, and the lateral support members, and the chocks of the intermediate cylinder are moved simultaneously with said bending block which supports them. It follows that each lateral support member is able to follow the vertical displacement of the working roll that it supports, while maintaining the ability to move radially relative to these same working rolls.

Finally, these same constructive arrangements allow each of the guiding devices of the lateral support members to remain advantageously fixed relative to the rolling stand during disassembly of the intermediate rolls out of said rolling stand. Indeed, each lateral support member supported by at least one of said integral guiding devices to a bending block is able to remain axially fixed relative to the rolling stand during extraction from the rolling stand of an intermediate cylinder supported by the same block of bending. Thus, disassembly of the lateral support members is unnecessary during extraction of an intermediate cylinder, and the constructive arrangements of the rolling stand according to the invention make it possible to hold in place in the rolling stand said parts of lateral supports during the extraction of the intermediate cylinders, regardless of their ability to move radially relative to the work rolls.

In particular, the rolling stand according to the invention comprises at least one means for moving one or more lateral support members adapted to move and position said lateral support member or said lateral support members. In addition, said moving means is particularly adapted to be guided by a guide member directly or indirectly secured to the amounts of the rolling stand. In particular, said displacement means comprises at least one thrust member, for example a displacement actuator, mechanical or hydraulic, guided by at least one guiding member directly or indirectly integral with one or more amounts of the rolling stand and able to radially move a lateral support member relative to the working cylinder that it is able to support. The displacement actuators are able to synchronously move the ends of the lateral support members, said ends being in particular intended to support one of said working rolls. Said displacement actuator is for example a screw and nut device, or a wheel and worm device, or a wedge device actuating the lateral support members, directly or via a beam distribution of thrust forces. In general, the rolling stand according to the invention is characterized in that two thrust members operable in a synchronized manner by a screw device are able to act synchronously each on one end of one of said members. lateral support for positioning, or according to another configuration, two thrust members operable synchronously by a wedge device are adapted to act synchronously each on one end of one of said lateral support members in order to its positioning. In both cases, a thrust force distribution beam may be interposed between the lateral support member and at least one of its thrust members. In particular, the distribution beam of the thrust forces is intercalable between a support arm of the lateral support member and its or thrust members.

In addition, the rolling stand according to the invention comprises at least one displacement member of an intermediate cylinder which may for example be a mechanical or hydraulic displacement actuator of said intermediate cylinder. In particular, each displacement actuator of an intermediate cylinder is adapted to be guided by a guide device of the intermediate cylinder directly or indirectly secured to one or more amounts of the rolling stand and to move axially said intermediate cylinder. Each of the intermediate roll guide devices allows a vertical displacement of the chocks of the intermediate rolls in line with the vertical displacement of the bending blocks supporting said chocks of the intermediate rolls.

Advantageously, unlike rolling cages characterized by an axial movement of the journals of the intermediate cylinders relative to their bearings to allow the axial displacement of the intermediate cylinders and requiring trunnions formed of a surface of extremely strong material, the present invention gives the possibility to the chocks of the intermediate rollers to move axially by sliding in the choke guide housings arranged in the blocks of hydraulic bending and thus avoids any relative displacement of the journals relative to their bearings, while allowing a fixity of the journals relative to their bearings. It is therefore possible to use standard bearings with a high load capacity, for example four rows of rollers mounted in TQO configuration. Advantageously, the fixity of the journals relative to their bearings makes it possible to choose the latter in a range of sealed bearings, ie intrinsically sealed or assembled / sealed in their chocks. The rolling stand according to the invention is thus characterized in particular by the fact that each of said intermediate rolls comprises at each of its ends a trunnion adapted to be fitted with a bearing with a high radial and axial load capacity, said bearing being suitable for be mounted in each of the chocks of said intermediate cylinders.

In addition and in particular, the rolling stand according to the invention is characterized in that said lateral support member comprises a lateral support cylinder and its support rollers. In addition, particularly advantageously, said lateral support member according to the invention may comprise in particular at least one support arm adapted to support said lateral support cylinder and its rollers, said support arm being in particular usable as a rail or as support disassembly rail on which can roll wheels or disassembly pads fitted to the chocks of the intermediate cylinders. Thus, each lateral support member is able to include a disassembly rail suitable for disassembling a cylinder intermediate. In particular, the lateral support members located on either side of the clamping plane and supporting the same working cylinder each comprise said disassembly rail for disassembly of the intermediate cylinder capable of being in contact with said working cylinder, ie its extraction out of the cage, in particular by sliding of shoes or rolling of wheels equipping the chocks of said intermediate cylinder on or in said rail.

On the other hand, the rolling stand according to the invention is particularly suitable for comprising at least one oil dispenser member adapted to be mounted on at least one lateral support member support arm, in particular for supplying fluid to the nozzles able to lubricate the strip and / or the working rolls, see other rolls intended for rolling. Advantageously, since the lateral support members are integral with the bending blocks and not the chocks of the intermediate rolls, as well as able to remain in the rolling stand during extraction / disassembly and reassembly of said intermediate rolls, it is not necessary, as in EP 0 937 517 , to implement systems for automatic coupling of lubricating oil supply pipes of the cylinders and rollers of lateral support members. According to the present invention, the oil distribution members can be mounted on the support arms of the lateral support members, and powered by flexible pipes connectable to fixed feed points on the amounts of the rolling stand and allowing radial adjustment movements of the lateral support members relative to the working rolls.

According to one variant, the rolling stand according to the invention is in particular characterized in that a shim is positionable by means of a jack between one end of a support member lateral and one of said thrust members, said shim being adapted to be eclipsed. In particular, two shims are positionable synchronously each between a thrust member and a lateral support member. They advantageously allow rapid disassembly of an intermediate cylinder by eclipsing said wedges, said eclipse resulting in a rapid separation of the lateral support members of the working rolls they are able to support.

Finally, according to a particular configuration of the rolling stand according to the invention, the latter comprises eight separate hydraulic bending blocks supporting the chocks of the upper and lower intermediate rolls, respectively four upper bending blocks supporting the two chocks of the upper intermediate roll and four lower cambering blocks supporting the two chocks of the lower intermediate cylinder, said camber blocks being adapted to cooperate with mechanical or hydraulic actuators arranged between each pair of upper and lower bending blocks and ensuring a vertical displacement of said bending blocks relative to the rolling stand amounts in groups of four, a first group of four synchronized upper blocks and a second group of four synchronized lower blocks, said eight bending blocks further comprising chock guide housings in which they are able to slide or slide axially one of the two protuberances located on each of the two side faces of the chocks, said protuberances making said chocks slid axially with a slight clearance in the choke guide housings arranged in each of the eight blocks hydraulic bending, and two devices for guiding each of the lateral support members of each of the upper and lower working rolls, respectively a first guide device integral with a first bending block, and a second guide device integral with a second block of bending, the first and the second bending block supporting the same lateral support member.

Figure 1

exemple de réalisation d'une cage de laminage sexto appuyé latéralement selon l'art antérieur.

Figure 2

exemple de réalisation d'un organe d'appui latéral solidaire d'empoises axialement fixes d'un cylindre intermédiaire selon l'art antérieur.

Figure 3

exemple de réalisation d'un organe d'appui latéral solidaire d'empoises axialement mobiles d'un cylindre intermédiaire selon l'art antérieur.

Figure 4

exemple de réalisation d'organes d'appui latéraux solidaires de montants d'une cage de laminage selon l'art antérieur.

Figure 5

exemple de réalisation d'une cage de laminage selon l'invention.

Figure 6

exemple d'une première réalisation d'un moyen de déplacement d'organes d'appuis latéraux selon l'invention.

Figure 7

exemple d'une seconde réalisation d'un moyen de déplacement d'organes d'appuis latéraux selon l'invention.

Figure 8

exemple d'utilisation d'organes d'appuis latéraux comme rails de démontage des cylindres intermédiaires selon l'invention.

In order to better understand the present invention, examples of embodiments and applications are provided using the following figures:

Figure 1

exemplary embodiment of a sexto rolling mill supported laterally according to the prior art.

Figure 2

embodiment of a lateral support member secured to axially fixed chocks of an intermediate cylinder according to the prior art.

Figure 3

embodiment of a lateral support member secured to axially movable chocks of an intermediate cylinder according to the prior art.

Figure 4

embodiment of lateral support members secured to the uprights of a rolling stand according to the prior art.

Figure 5

embodiment of a rolling stand according to the invention.

Figure 6

example of a first embodiment of a means for moving lateral support members according to the invention.

Figure 7

example of a second embodiment of a means for moving lateral support members according to the invention.

Figure 8

example of use of lateral support members as disassembly rails of the intermediate cylinders according to the invention.

The figure 1 shows an exemplary embodiment according to the prior art of a sexto rolling mill supported laterally. Conventionally, a sexto rolling cage comprises two working rolls 1u, 1d of small diameters, respectively an upper work roll 1u located above a rolling plane D of a strip to be rolled, and a lower work roll 1d located below said plane of travel D of the strip to be rolled. Said laminating strip runs between the two working cylinders 1u, 1d supported vertically, and in particular driven by friction, by a pair of intermediate cylinders 2u, 2d, themselves supported vertically by a pair of support rollers 3u, 3d pressing on said pair of intermediate cylinders 2u, 2d. The working rolls 1u, 1d have their longitudinal axis of rotation in a plane substantially perpendicular to the running plane of the band, and commonly called the clamping plane P. In case of lateral support, each work roll is not only supported by a part vertically by the two intermediate cylinders 2u, 2d, ie respectively the upper intermediate cylinder 2u and the lower intermediate cylinder 2d, themselves supported by the two support cylinders 3u, 3d vertical, ie respectively the support cylinder upper 3u and the lower support cylinder 3d, but also, on the other hand, each working cylinder 1u, 1d is supported laterally by lateral support members each comprising in particular a lateral support cylinder 4u, 4d, supported by two rows of support rollers 5 mounted side by side. Thus, two lateral support cylinders arranged symmetrically on either side of the working cylinder are able to laterally support said working cylinder. In addition, each row of support rollers 5 is composed of a plurality of rollers arranged side by side along a common axis on a common two-row support arm.

The figure 2 describes an exemplary embodiment of a lateral support member 7 of a sexto rolling cage according to the prior art, said lateral support member 7 being integral with chocks 21 of an intermediate cylinder 2. Said chocks 21 are axially fixed relative to the uprights 6 of the rolling stand. The intermediate cylinder 2, in particular an upper intermediate cylinder as presented in Fig. 2 is supported at each of its ends by one of said chocks 21 axially fixed relative to the uprights 6 of the rolling stand, but capable of vertical displacements between these same amounts. A guide in rotation of the intermediate cylinder 2 in its chock is provided by a bearing 22 comprising in particular an outer ring 221 and cylindrical rollers 222. During an axial displacement of the intermediate cylinder 2, a journal 23 of said intermediate cylinder is able to slide axially on the cylindrical rollers 222.

Two lateral support members 7, only one of which is shown here, are distributed on either side of a clamping plane P which can in particular comprise the longitudinal axes of rotation of the working cylinders 1, so as to support the cylinder laterally. 1 with which they are in contact. Each lateral support member 7 comprises in particular a support arm 71 adapted to carry both a lateral support cylinder 4 and its support rollers 5. Thus, two lateral support cylinders 4, only one of which is shown, are distributed on either side of the clamping plane P. Each a pair of lateral support cylinders 4 is able to laterally support one of said working rolls 1. Each lateral support roll is itself supported by two rows of rollers 5. The lateral support member 7 is furthermore able to pivot around a guiding member 72 secured to the chock 21.

The constructive arrangement of the rolling stand presented in Fig. 2 shows that it is impossible to carry out operations of extraction and maintenance of the intermediate cylinders 2 without preventing, using a specific tool, the pivoting of the lateral support members 7 around their guide member 72 It also shows that it is impossible to rectify the active face of the intermediate rolls 2 between two rolling campaigns without disassembling the chocks 21 and the two lateral support members 7 that they support.

In addition, since the chocks 21 are axially fixed relative to the uprights 6 of the rolling stand, the lateral support members 7 are also fixed with respect to said uprights 6 of the rolling stand, and therefore with respect to the work rolls. 1. The axial displacement of the intermediate cylinder 2 is thus ensured by axial sliding of its journals 23 with respect to the chock 21 and the bearing 22. To this end, the journals 23 of the intermediate cylinder 2 must be extended by a corresponding length. at the axial displacement distance of the intermediate cylinder 2.

The figure 3 discloses an embodiment according to the prior art of a lateral support member 7 of a sexto rolling stand, said lateral support member 7 being secured to chocks 21 of an intermediate roll 2. Unlike of the rolling stand described in Fig. 2 said chocks 21 are axially movable relative to the uprights 6 of the cage rolling. Indeed, said chocks 21 are movable axially and vertically relative to the uprights 6 of the rolling stand, while being able to support the intermediate cylinder 2 and the lateral support members 7 they support.

In particular, the intermediate cylinder 2, in particular an upper intermediate cylinder as presented in Fig. 3 , is capable of being supported at each of its ends by said chock 21 axially displaceable relative to the uprights 6 of the rolling stand and capable of vertical displacements between these same uprights 6. A bearing 22 composed of an outer ring 221, d an inner ring 224 and rollers 222 is adapted to guide the intermediate cylinder 2 in rotation in its chock. During axial displacement of the intermediate cylinder 2, the chocks 21 of said intermediate cylinder are able to move synchronously with said intermediate cylinder, while the journals 23 of said intermediate cylinder are able to remain fixed relative to the bearings 22.

The working cylinder 1 is supported laterally on two lateral support cylinders 4, only one of which is shown. Each lateral support cylinder is supported by two rows of rollers 5. A lateral support member 7 comprises in particular a support arm 71 adapted to bear both the lateral support rollers 4 and the rollers 5. This support member lateral 7 is further able to pivot about a guide member 72 integral with the chock 21 and to accompany the chock 21 during its axial displacement.

According to the constructive provision presented in Fig. 3 , the chocks 21 are axially movable relative to the uprights 6 of the rolling stand and synchronously accompany the axial displacement of the intermediate roll. Therefore, the lateral support members 7 are able to move relative to the working roll 1, which remains axially fixed between axial stops (not shown) which are themselves, during rolling, axially fixed relative to the uprights 6 of the rolling stand.

The figure 4 shows an exemplary embodiment of lateral support members 7 of a rolling stand according to the prior art, said lateral support members 7 being secured to the uprights 6 of the rolling stand. The rolling stand is equipped with two working rolls 1, each supported on the one hand vertically by two intermediate rolls 2, and on the other hand laterally by two lateral support rollers 4 themselves supported by two rows of rollers. support 5 mounted side by side. In particular, each of said intermediate cylinders 2 is itself supported by a vertical support cylinder 3. Under the action of a mechanical or hydraulic actuator (not shown), a support arm 71 adapted to carry both a lateral support cylinder 4 and its rollers 5 is able to slide in a guiding device 72 integral with the upright 6 of the rolling stand. In case of vertical movement of the working roll 1, for example a vertical movement of an upper work roll towards the upper support roll, an interference 8 between the work roll 1 and at least one of the two support rolls lateral 4 can take place. In other words, the working roll 1 is able to interfere with a lateral support roll 4, for example by contacting the latter, during a vertical displacement of said work roll 1.

The figure 5 shows an exemplary embodiment of a rolling stand according to the invention. In particular, the rolling stand comprises two working rolls 1 capable of gripping a strip to be rolled, more specifically, an upper working roll situated above a rolling plane D of the rolling mill. rolling strip, and a lower working cylinder located below said plane of travel D of the strip to be rolled, the upper and lower working rolls 1 having their longitudinal axes of rotation in a clamping plane P substantially perpendicular to the plane of two rolls 2, respectively an upper intermediate roll adapted to be in contact with the upper working roll and a lower intermediate roll adapted to be in contact with the lower work roll, two rolls of rolling tape D, two intermediate rolls 2, support 3, respectively an upper support cylinder adapted to be in contact with the upper intermediate cylinder, and a lower support cylinder adapted to be in contact with the lower intermediate cylinder, the upper and lower bearing rolls being adapted to transmitting a clamping force to the work rolls 1 via the intermediate rolls, or in other words, the rolling stand comprises six cylinders superimposed vertically in a configuration of sexto rolling cage, and further comprises at least one lateral support member 7 adapted to laterally support one of said work rolls 1, in particular a first and a second upper lateral support member, situated respectively on either side of said clamping plane and able to laterally support said upper work roll 1, and a first and a second lower lateral support member, located on the one side and on the other hand of said clamping plane and able to support laterally the lower work roll 1, the roll stand according to the invention is characterized in that it comprises at least one bending block 9 intended for the bending of said intermediate rolls 2 , said bending block 9 being able to be moved vertically with respect to uprights 6 of the rolling stand and to support said lateral support member 7 In particular, said bending block 9 is also advantageously able to withstand axial displacement of at least one chock 21 of intermediate rolls 2 and to be used to bend at least one of said intermediate rolls 2. Thus, the rolling stand according to the invention comprises in particular at least one bending block 9 capable of moving vertically relative to the uprights 7 of the roll stand, while serving as support for said lateral support member 7, at least one chock 21 of an intermediate cylinder 2, and allowing axial displacement of said chock 21 with respect to the uprights 6 of the rolling stand, and therefore of the intermediate cylinder 2 that she supports.

The constructive arrangements described by the Fig. 5 allow the lateral support members 7 to remain axially fixed with respect to the working rolls during axial displacement of the intermediate rolls, to remain fixed with respect to the intermediate rolls during a vertical displacement of said intermediate rolls, to remain fixed with respect to the stand rolling during dismounting of the intermediate rolls out of said cage, and in all circumstances, said constructive arrangements according to the invention allow the lateral support members to remain adjustable radially relative to the working rolls.

In particular, each of said lateral support members 7 comprises a support arm 71 adapted to carry a lateral support cylinder 4 and support rollers 5. In particular, the lateral support members are capable of laterally supporting said working rolls 1 by means of said lateral support rollers 4. Each of these latter is able to laterally contact said working rolls in order to keep the work roll 1 in a lateral position substantially constant or according to a set position. Indeed, each side of one of said working cylinders 1 is adapted to be supported, by pressing against one of its generatrices, by one of said lateral support cylinders, distributed thereby on both sides of said clamping plane P. In particular, said lateral support rollers 4 are further themselves supported laterally by two rows of said support rollers mounted side by side.

In particular, the intermediate cylinders 2 are capable of being supported at each of their ends by said chock 21 axially movable with respect to the uprights 6 of the rolling stand, said mobility of the chock resulting for example from a sliding of parts of said chock 21 on parts of the bending blocks 9 provided for this purpose.

Each lateral support member is in particular adapted to pivot about a guiding device 72, or more precisely, around an axis of rotation of a guiding device 72 integral with one of said shafting blocks 9, or still to slide in a direction or a path defined by said guide member 72. In particular, a lateral support member displacement means, comprising for example a thrust member 73, is adapted to rotate said member of lateral support around said guiding device 72, in particular around its axis of rotation. In particular, the support arm 71 of said lateral support member is able to pivot about said guiding device 72, in particular under the action of said thrust member 73 capable of taking up radial forces received by the work rolls 1 during the rolling. To ensure a good recovery of these radial forces by limiting the risk of bending of the support arm 71, a force distribution beam 731 with high inertia is intercalable between the thrust members 73 and said support arm 71 to distribute the reactions of the thrust members 73 over the entire length of the support arm 71. Figures 6 and 7 following show an example of implantation of such a force distribution beam 731.

Each of the thrust members 73 of said moving means is in particular actuable by at least one screw or wedge actuator 74 capable in particular of synchronously actuating at least two thrust members 73, each located at a longitudinal end of the lateral support member, said longitudinal end referring in particular to each of the two ends of the lateral support member 7 according to the width of the strip. A jack 75 is particularly capable of acting, ie exerting a force, between a bending block 9 and a point of articulation 76 of a lateral support member 7 supported by the guiding device of said bending block, in order to pivoting said lateral support member about an axis of rotation of said guide device 72 integral with said bending block 9. Advantageously, said pivoting allows positioning of said lateral support members when the thrust members 73 are in a retreating position. In particular, a support arm 71 of a lateral support member 7 comprises said hinge point 76. In this case, said jack 75 is for example a hydraulic jack integral with one of said bending blocks and able to rotate said support arm 71 including said hinge point 76 about said axis of rotation of the guiding device 72.

On the other hand, each bending block 9 is in particular able to be moved vertically by an actuator 92, arranged in particular between the bending blocks 9 of a pair of bending blocks comprising an upper bending block and a boulder block. lower bending, said upper and lower bending blocks being distributed on either side of the plane of travel of the strip to be rolled, close to the same end of a working cylinder 1. Thus, the rolling stand according to the the invention comprises in particular hydraulic actuators 92 capable of ensuring a vertical displacement said bending blocks 9 relative to the uprights 6 of the rolling stand. In particular, four hydraulic actuators 92 can be arranged between a first group of four upper bending blocks and a second group of four lower bending blocks, each of said actuators being able to vertically move the bending blocks of a pair of boulders. cambering 9 comprising an upper bending block and a lower bending block. For this purpose, a hydraulic actuator 92 may be arranged between the bending blocks of each pair of bending blocks 9, in order to vertically and synchronously move groups of four bending blocks 9 relative to the uprights 6 of the bending cage. rolling, in particular said first group of four upper bending blocks movable synchronously by their hydraulic actuators and said second group of four lower blocks synchronously movable by their hydraulic actuators. In particular, the bending blocks 9 are able to move vertically on bending block supports 91 integral with the uprights 6 of the rolling stand.

The figure 6 presents a first exemplary embodiment according to the invention of a means for moving lateral support members, comprising in particular two thrust members 73. In particular, the support arm 71 of lateral support member is adapted to be pushed by the two thrust members 73. The latter are able to be guided on the uprights 6 of the rolling stand and / or on bending block supports integral with said uprights and to act in a synchronized manner. These thrust members may in particular be each actuated by a screw 741 fixed in rotation and adapted to reversibly axially move said thrust member 73 under the action of a wheel and worm member or a deflection member d 742 bevel gear angle. The bevel gear 742 is particularly operable by a motor 743. Wedges 744 able to be eclipsed and actuated by jacks 745 in particular make it possible to quickly release the support arm 71 from a lateral support member. Each of said wedges is in particular positionable between said thrust member and said support arm 71. Advantageously, a force distribution beam 731 with high inertia is in particular intercalable between the thrust members 73 and the support arm 71 in order to distribute the thrust forces along the entire length of said support arm 71.

The figure 7 presents a second example of a means of displacement of lateral support members according to the invention, comprising in particular two thrust members 73 able to move, in particular by pushing, the lateral support support arm 71. Each of said thrust 73 is particularly suitable for being guided on uprights 6 and / or bending block supports. These thrust members are in particular synchronously actuable by two corner boxes 746. In particular, under the action of a wedge ramp 747 actuable by a jack 748, said thrust members 73 are in particular able to move axially . Advantageously, pins 749 engageable in grooves parallel to the slope of the corners in particular allow a backward movement of the thrust members 73 and provide a reminder of the displacement of said thrust members. Similar to the constructive provisions presented in Fig. 6 shims 744 capable of being eclipsed and actuable by jacks 745 make it possible in particular to quickly release the support arm 71 from a lateral support member. Said wedges are each in particular positionable by means of said jacks 745 between said thrust member and said support arm 71. Advantageously, a force distribution beam 731 with high inertia is in particular intercalable between the thrust members 73 and the support arm 71 in order to distribute the thrust forces along the entire length of said support arm 71.

The figure 8 shows an example of use of lateral support members 7 as dismantling rails of the intermediate cylinders 2 according to the invention. Upper and lower bending blocks 9d are displaceable in disassembly position by displacement on bending block supports 91, said bending block supports 91 being integral with uprights 6 of the rolling stand. In particular, each support arm 71 of each of said lateral support members is adapted to be pivoted about an axis of rotation of the guiding device 72 which supports it, to ensure free passage of the upper chocks 21u and lower 21d , respectively carrying the upper intermediate cylinder 2u and the lower intermediate cylinder 2d.

On the other hand, each of the upper support arms 71u of the upper lateral support members is adapted to comprise in particular a sliding surface 711u or rolling adapted to cooperate with rollers or sliding pads (not shown) can equip 211u ears of higher chocks 21u. Thus, in the disassembly position, an extraction of an upper intermediate cylinder 2u carried by said upper chocks 21u able to move axially by sliding or rolling respectively said pads or said wheels on said surfaces 711u is achievable by axial displacement of said chocks on the upper support arms 71u of the lateral support members to a disassembly carriage (not shown) out of the rolling stand.

Similarly, each lower support arm 71d of lower lateral support member comprises a sliding surface 711d or rolling allowing the lower chocks 21d to move axially by sliding or rolling respectively by means of sliding shoes or rollers (not shown) which can equip surfaces 211d of said lower chocks 21d, said sliding pads or rollers being intended to cooperate with the sliding or rolling surfaces 711d to allow extraction of the lower intermediate cylinder 2d and its lower chocks 21d from the rolling stand to a dismounting carriage.

• les organes d'appuis latéraux restent axialement fixes par rapport aux cylindres de travail pendant le déplacement axial des cylindres intermédiaires, ce qui diminue significativement les efforts axiaux engendrés par le déplacement des dits cylindres intermédiaires sur les butées axiales des cylindres de travail et le frottement des cylindres de soutien latéral sur les cylindres de travail;
• les organes d'appuis latéraux restent fixes par rapport aux cylindres intermédiaires pendant le déplacement vertical de ceux-ci, ce qui prévient tout risque de dégradation de l'installation par interférence entre les cylindres de travail et les appuis latéraux lors des phases d'ouverture et de fermeture de la cage de laminage;
• les organes d'appuis latéraux restent fixes par rapport à la cage de laminage pendant le démontage des cylindres intermédiaires hors de ladite cage, ce qui permet de procéder à la maintenance des cylindres intermédiaires comme dans une cage 6-High conventionnelle ou une cage 4-High, sans outillages spéciaux et sans nécessité de démontage des empoises;
• ils rendent caduques l'emploi d'organes de connexion rapide ou automatique de circuits de lubrification des roulements des cylindres intermédiaires lors de l'extraction et du remontage de ces cylindres en raison de l'utilisation de roulements étanches ne nécessitant pas de circuit de lubrification;
• ils permettent d'utiliser pour les cylindres intermédiaires, des roulements standards à forte capacité de charge, moins coûteux et beaucoup plus résistants que des roulements spéciaux sans bague intérieure;
• ils permettent d'utiliser pour les cylindres intermédiaires, des roulements étanches permettant l'utilisation de fluides de laminage sélectionnés indépendamment des nécessités de lubrification des roulements;
• ils sont libres de contraintes liées à une matière de surface et une géométrie des tourillons permettant un déplacement axial desdits tourillons des cylindres intermédiaires par rapport à leurs roulements. En effet, ils suppriment la nécessité d'utiliser des tourillons de cylindres intermédiaires de grande longueur et spécialement durcis, qui servaient auparavant au déplacement axial du cylindre intermédiaire;
• ils assurent un déplacement axial en charge des cylindres intermédiaires sans glissement des roulements par rapport aux tourillons;
• ils rendent caduque l'utilisation d'organes de connexion rapide ou automatique de circuits de lubrification des cylindres de soutien latéral et des galets qui les soutiennent du fait que les bras supports aptes à les supporter restent dans la cage de laminage lors de l'extraction et du remontage des cylindres intermédiaire;
• ils rendent caduque l'utilisation d'organes de connexion rapide ou automatique de circuits de lubrification et de refroidissement de la bande laminée et de la surface des cylindres de laminage lors de l'extraction et du remontage des cylindres intermédiaires lorsque des buses de pulvérisation du fluide de lubrification sont fixées sur les organes d'appui latéraux
• ils assurent une fixité axiale des organes d'appuis latéraux par rapport à des butées axiales des cylindres de travail, tout en conservant une capacité de mouvement radial de ces organes d'appuis latéraux par rapport auxdits cylindres de travail;
• ils assurent une solidarisation des organes d'appuis latéraux par rapport aux empoises des cylindres intermédiaires afin qu'organes de soutien latéraux et cylindres intermédiaires se déplacent verticalement de manière synchrone, tout en conservant la capacité de mouvement radial des organes d'appuis latéraux par rapport aux cylindres de travail;
• ils garantissent une fixité axiale des organes d'appui latéraux par rapport à la cage de laminage tout en leur conservant une capacité de mouvement radial de ces organes d'appuis latéraux par rapport aux cylindres de travail et tout en conservant également leur mouvement vertical synchrone avec les dispositifs de support des cylindres intermédiaires;
• ils permettent de simplifier des opérations de changement des cylindres, en particulier des ensembles de cylindres intermédiaires et de travail supérieurs et inférieurs.

In summary, the rolling stand and the method of operation of a rolling stand according to the invention have several advantages over existing operating methods and rolling stands in that:

• the lateral support members remain axially fixed with respect to the working rolls during the axial displacement of the intermediate rolls, which significantly reduces the axial forces generated by the displacement of said intermediate rolls on the axial stops of the work rolls and the friction of the side support cylinders on work rolls;
• the lateral support members remain fixed relative to the intermediate cylinders during the vertical displacement thereof, which prevents any risk of degradation of the installation by interference between the working rolls and the lateral supports during the opening phases and closing the rolling stand;
• the lateral support members remain fixed relative to the rolling stand during disassembly of the intermediate rolls from said cage, which allows perform the maintenance of the intermediate cylinders as in a conventional 6-High cage or a 4-High cage, without special tools and without the need to dismantle the chocks;
• they make obsolete the use of quick connection devices or automatic lubrication circuits of the bearings of the intermediate cylinders during the extraction and reassembly of these cylinders due to the use of sealed bearings that do not require a lubrication circuit ;
• they make it possible to use, for the intermediate rolls, standard bearings with a high load capacity, which are less expensive and much more resistant than special bearings without an inner ring;
• they allow to use for the intermediate cylinders, sealed bearings allowing the use of selected rolling fluids independently of the lubrication requirements of the bearings;
• they are free of constraints related to a surface material and a geometry of the journals allowing axial displacement of said journals of the intermediate rolls relative to their bearings. Indeed, they eliminate the need to use journals of intermediate cylinders of great length and specially hardened, which were previously used for the axial displacement of the intermediate cylinder;
• they provide an axial displacement in load of the intermediate rolls without sliding bearings relative to the trunnions;
• they make obsolete the use of quick connection devices or automatic lubrication circuits side support cylinders and rollers that support them the support arms capable of supporting them remain in the rolling stand during the extraction and reassembly of the intermediate rolls;
• they render obsolete the use of quick connection devices or automatic lubrication circuits and cooling of the rolled strip and the surface of the rolling rolls during extraction and reassembly of the intermediate rolls when the spray nozzles of the lubrication fluid are attached to the lateral support members
• they provide an axial fixity of the lateral support members relative to axial stops of the working rolls, while maintaining a capacity for radial movement of these lateral support members relative to said working rolls;
• they provide a securing of the lateral support members relative to the chocks of the intermediate rolls so that lateral support members and intermediate rolls move vertically synchronously, while retaining the radial movement capacity of the lateral bearing members relative to working cylinders;
• they guarantee an axial fixity of the lateral support members with respect to the rolling stand while retaining a capacity for radial movement of these lateral support members relative to the working rolls and while also maintaining their synchronous vertical movement with support devices for the intermediate cylinders;
• they make it possible to simplify cylinder change operations, in particular upper and lower sets of intermediate and working rolls.

Claims (15)

1. Roll stand including two working rollers (1) capable of gripping a strip to be rolled, two intermediate rollers (2), two bearing rollers (3), at least one side bearing unit (7) capable of laterally supporting one of said working rollers (1), at least one camber block (9) for cambering said intermediate rollers (2) and capable of vertical movement relative to the posts (6) of the roll stand, characterised in that said camber block (9) is capable of supporting said side bearing unit (7).
2. Roll stand according to claim 1, characterised in that said camber block (9) includes a guide device (72), integrated with said camber block (9) and capable of supporting and guiding said side bearing unit (7).
3. Roll stand according to one of claims 1 or 2, characterised in that said camber block (9) is capable of supporting at least one chock (21) of an intermediate roller (2) as well as an axial movement of the latter.
4. Roll stand according to one of claims 1 to 3, characterised in that said side bearing unit (7) is capable of pivoting about said guide device (72) integrated with said camber block (9).
5. Roll stand according to one of claims 1 to 4, characterised in that an actuator (92) is capable of moving said camber block (9) vertically.
6. Roll stand according to claim 5, characterised in that a first group of four camber blocks (9) capable of acting as a support for the chocks (21) of an upper intermediate roller and a second group of four camber blocks (9) capable of acting as a support for the chocks (21) of a lower intermediate roller, can each move vertically relative to the posts (6) of the roll stand in a synchronised manner by means of an actuator (92).
7. Roll stand according to one of claims 1 to 6, characterised in that axial movement units are capable of moving said intermediate rollers (2) axially by moving the chocks (21) of said intermediate rollers relative to the camber blocks (9).
8. Roll stand according to one of claims 1 to 7, characterised in that at least one means of movement of a side bearing unit (7) is capable of moving and positioning said side bearing unit (7).
9. Roll stand according to claim 8, characterised in that said means of movement includes at least one thrust unit (73).
10. Roll stand according to claim 9, characterised in that two thrust units (73) which can be actuated in a synchronised manner by a screw device (74) are capable of acting in a synchronised manner, each on one end of one of said side bearing units (7) with a view to positioning it.
11. Roll stand according to claim 9, characterised in that two thrust units (73) which can be actuated in a synchronised manner by a wedge device are capable of acting in a synchronised manner, each on one end of one of said side bearing units (7) with a view to positioning it.
12. Roll stand according to one of claims 9 or 11, characterised in that a shim can be positioned by means of a jack between said end of a side bearing unit (7) and one of said thrust units (73).
13. Roll stand according to one of claims 10 to 12, characterised by high-inertia thrust load distribution beam (731) which can be inserted between a side bearing unit (7) and at least one of its thrust units.
14. Roll stand according to one of claims 1 to 13, characterised in that each side bearing unit is capable of including a dismantling rail capable of being used for dismantling an intermediate roller.
15. Method for operating a roll stand including two working rollers (1) capable of gripping a strip to be rolled, two intermediate rollers (2), two bearing rollers (3), at least one side bearing unit (7) capable of laterally supporting one of said working rollers (1), at least one camber block (9) for cambering said intermediate rollers (2) and capable of vertical movement relative to the posts (6) of the roll stand, characterised by a side bearing unit (7) being supported by said camber block (9) and by adjustable positioning of the side bearing unit (7) providing for:

    - first, holding the side bearing unit (7) fixed relative to the working roller (1) capable of being supported by said side bearing unit (7) during axial movement of the intermediate roller (2) capable of being in contact with said working roller (1);

    - second, holding the side bearing unit (7) fixed relative to the intermediate roller (2) during its vertical movements capable of being in contact with the working roller (1) capable of being supported by said side bearing unit (7);

    - and third, holding the side bearing unit (7) fixed relative to the roll stand during dismantling of said intermediate rollers (2).

Images