Rolling method with a step for adjusting the interspace between the lateral backup roll and the support roll

Abstract

Disclosed is a rolling method for rolling a strip including: rolling the strip by a pair of working rolls; transmitting a rolling force to the working rolls by a pair of support rolls; holding each of the working rolls by a pair of side support rollers; supporting each side support roller by two rows formed by rollers; supporting each row formed by the rollers, by a bearing support carrying rollers, the bearing support mounted pivotally on an articulation axis. The dimensions of a first interspace between the side support roller and the support roll and a second interspace between the strip and the assembly consisting of side support roller and bearing support vary in the course of the rolling. The method includes adjusting the dimension separating the axis of the support roll and the axis of the side support roller defining the first interspace.

Claims

1. A rolling method adapted to a mill for rolling a strip (ST), comprising: rolling said strip using a pair of working rolls (WR) with parallel axes with said strip being taken between said working rolls (WR) and travelling between the pair of working rolls, each of said working rolls having at least one generatrix of contact with the strip, transmitting a rolling force to said working rolls (WR) using a pair of support rolls (SR), the rolling force being normal to the strip, said working rolls (WR) and said support rolls (SR) being situated on the same side of the strip being in contact with each other along a common support generatrix in order to transmit said rolling force, maintaining the at least one contact generatrix and the axes of said working rolls in a plane perpendicular to a direction of travel of the strip, holding of each of said working rolls (WR) by a pair of side support rollers (SSR), situated on either side of said plane perpendicular to the direction of travel of the strip, each of the side support rollers (SSR) being able to exert, along a bearing generatrix of said working roll (WR), a force holding an axis of the working roll (WR) in a given position with respect to a rolling cage of the mill and with respect to said side support rollers, supporting of each of said side support rollers by means of two rows formed by a plurality of rollers (G) mounted side by side, for holding the side support rollers (SSR) in a given position, supporting each of the two rows formed by said plurality of rollers (G), said supporting being provided by a bearing support (BS) carrying the two rows of rollers (G), wherein said bearing support (BS) is mounted pivotably by a support arm (AR) on an articulation axis (A1), the articulation axis (A1) being parallel to the support roll (SR), said providing a support including pivoting of the bearing support (BS) around said articulation axis (A1), wherein the support roll (SR) is carried by an axis support (AS) formed by chocks (Ep), or Maes blocks (MB) cambering the support roll, said axis support (AS) being fixed with respect to the axis of the support roll (SR), wherein dimensions of a first interspace (It1) defined between the side support roller (SSR) and the support roll (SR) and a second interspace (It2) defined between the strip (ST) and the assembly consisting of the side support roller (SSR) and the bearing support (BS) vary during rolling because of reductions in diameters of the support roll and working roll caused by wear and planing of the support and working rolls, and a readjustment step of adjusting the dimensions of said first interspace (It1) and of the second interspace (It2) by carrying out an adjustment of the dimension separating an axis (A.sub.SR) of said support roll (SR) and the axis (A.sub.ssR) of said side support roller (SSR), said readjustment step being distinct and additional to the pivoting of the bearing support (BS) around said articulation axis (A1), wherein said bearing support (BS) is fixedly mounted removably on said support arm (AR), with an adjustable position on the support arm, wherein said adjustment of the dimension separating the axis of said support roll (SR) and the axis of said side support roller (SSR) implemented during the readjustment step is performed by a step of modifying the position of said bearing support (BS) on the length of said support arm (AR), said readjustment step being configured to change the dimension of the first interspace for a same first diameter of each of the working rolls (WR), a same second diameter of each of the side support rollers (SSR), and a same third diameter of each of the support rolls (SR), said first interspace being determined when said working roll (WR) is held by said pair of side support rollers (SSR).

2. The method according to claim 1, wherein said readjustment step consists of adjusting the dimension separating the axis of said support roll (SR) and the axis of said side support roller (SSR) so that the dimension of the first interspace is at least equal to a lower limit Δmin1 and the dimension of the second interspace is at least equal to a lower limit Δmin2, said lower limit Δmin1 and the lower limit Δmin2 being greater than or equal to 5 mm.

3. The method according to claim 1, wherein the diameter of the support roll (SR) is between a maximum diameter and a minimum diameter, further comprising defining a nominal diameter smaller than the maximum diameter and larger than the minimum diameter, said defining step comprising: maintaining a first rolling configuration without the readjustment step so long as the diameter of the support roll lies between the maximum diameter and the nominal diameter, obtaining a second rolling configuration, when the support roll is at the nominal diameter, by performing said readjustment step with reduction of the dimension separating the axis (A.sub.SR) of said support roll (SR) and the axis (A.sub.SSR) of said side support roller (SSR), maintaining said second configuration obtained by said readjustment step as long as the diameter of the support roll lies between the nominal diameter and the minimum diameter.

4. The rolling method according to claim 1, further comprising: using at least spray nozzles (SN1, SN2) to provide cooling by spraying of at least one jet of fluid onto at least part of the strip (ST) and at least part of one of said working rolls; and implementing a cooling step comprising at least one direct spraying of at least part of the working rolls (WR), on either side of said plane perpendicular to the direction of travel of the strip, said nozzles (SN1, SN2) producing: a jet (J1) directed towards the working roll (WR), from at least one side of the plane perpendicular to the direction of travel, the jet passing through said first interspace (It1) between the side support roller (SSR) and the support roll (SR), before reaching said working roll (WR), and/or a jet (J2) directed towards the working roll (WR), from at least one side of the plane perpendicular to the direction of travel, passing through the second interspace between the strip and the side support roller, before reaching said working roll and/or said strip.

5. The method according to claim 1, wherein the mill comprises a removable means of fixing between said bearing support (BS) and said support arm (AR), the means of fixing comprising a groove/key positive-location system (1) comprised of a key and a groove carried respectively by said bearing support (BS) and said support arm (AR), or vice versa, said key or the groove carried by the bearing support being offset in the longitudinal direction of the support arm (AR) with respect to a plane i) parallel to the side support roller, ii) passing through a median line (Md) to a segment which is perpendicular to the side support roller, said segment joining the two axes of the two rows of the rollers (G) mounted side by side for holding the side support rollers (SSR), and wherein, during the readjustment step, said adjustment of the dimension separating the axis of said support roll and the axis of said side support roller is performed by a step of turning over said bearing support (BS) on the support arm.

6. The method according to claim 1, wherein said readjustment step is implemented when rolling is interrupted, after planing of the working roll and/or of the support roll.

7. A mill for rolling a strip (ST) including at least one cage, comprising: a pair of working rolls (WR) with parallel axes, between which the strip (ST) passes, each of said working rolls having at least one generatrix of contact with the strip, trip, wherein at least one contact generatrix and the axes of said working rolls (WR) are situated, a pair of support rolls (SR), with axes parallel to a plane of the strip and situated on either side of said strip, said support rolls and working rolls situated on the same side of the strip being in contact with each other along a common support generatrix in order to transmit to the working rolls a rolling force normal to the strip, two pairs of side support rollers with parallel axes, said side support rollers in the same pair being situated symmetrically on either side of one of said working rolls, in a plane parallel to the strip, so that each of the side support rollers (SSR) in the same pair is able to transmit, along a bearing generatrix of said working roll (WR), a force affording holding in a given position in relation to the support roll (SR), a support for each of said support rollers by means of two rows formed by a plurality of support rollers (G) mounted side by side, for holding the side support rollers (SSR) in a given position, a bearing support (BS) providing support of each of the two rows formed by said plurality of support rollers by said bearing support (BS) carrying the two rows, said bearing support (BS) being mounted pivotally by a support arm (AR) on an articulation axis (A1), the articulation axis (A1) being parallel to the support roll, wherein the support roll (SR) is carried by an axis support (AS) formed by chocks (Ep) or Maes blocks (MB), said axis support (AS) being fixed with respect to the axis of the support roll, wherein the mill comprises, during the rolling of the strip, a first interspace (Itl) defined between the side support roller (SSR) and the support roll (SR) and a second interspace (It2) defined between the strip (ST) and the assembly consisting of the side support roller (SSR) and the bearing support (BS) vary during rolling because of the reductions in diameters of the support roll and of the working roll caused by wear or planing of the support and working rolls, and an adjustment device configured to adjust the dimensions of said first interspace (It1) and the dimension of the second interspace (It2) using an adjustment of the dimension separating the axis (AsR) of said support roll (SR) and the axis (AssR) of said side support roller (SSR), the adjustment being distinct and additional to the pivoting of the bearing support (BS) around said articulation axis (AS), wherein the adjustment device comprises said bearing support (BS) that is fixedly mounted removably on said support arm (AR), with a position adjustable on the support arm, and wherein the adjustment device is configured so that the adjustment of the dimension separating the axis (ASR) of said support roll (SR) and the axis (ASSR) of said side support roller (SSR) is performed by modifying the position of said bearing support (BS) on the support arm (AR), said adjustment device being configured to change the dimension of the first interspace for a same first diameter of each of the working rolls (WR), a same second diameter of each of the side support rollers (SSR), and a same third diameter of each of the support rolls (SR), said first interspace being determined when said working roll (WR) is held by said pair of side support rollers (SSR).

8. The mill according to claim 7, comprising a device configured for cooling by spraying at least one jet of fluid on at least part of the strip and at least part of one of said working rolls, comprising at least one system of nozzles with nozzles (SN1, SN2) configured to: produce a jet (J1) directed towards the working roll, from at least one side of the plane perpendicular to the direction of travel, the jet passing through the first interspace (Itl) between the side support roller (SSR) and the support roll (SR), before reaching said working roll (WR), and/or produce a jet (J2) directed towards the working roll, from at least one side of the plane perpendicular to the direction of travel, passing through the second interspace between the side support roller (SSR) and the strip (ST), before reaching said working roll and/or the strip.

9. The mill according to claim 7, wherein the adjustment device comprises a removable means of fixing between said bearing support and said support arm, the means of fixing comprising a groove/key positive-location system (1) comprised of a key and a groove carried respectively by said bearing support and said support arm, or vice versa, said key or the groove carried by the bearing support (BS) being offset in the longitudinal direction of the support arm with respect to a plane i) parallel to the side support roller, ii) passing through a median line (Md) to a segment, said segment being perpendicular to the side support roller, said segment joining the two axes of the two rows of the rollers (G) mounted side by side for holding the side support rollers (SSR), and wherein the adjustment device is configured so that said adjustment of the dimension separating the axis of said support roll and the axis of said side support roller is performed by turning over said bearing support (BS).

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The invention will be understood better from a reading of the description accompanied by the appended figures, depicting the invention, among which:

(2) FIGS. 5 to 10 illustrate a first embodiment of the invention for which the readjustment step is obtained by turning over the bearing supports fixed to the arms, the figures illustrating the rolling-mill cage according to various configurations of diameters of the working roll and diameters of the intermediate roll, as well as according to various configurations of the position of the assembly consisting of bearing support and side support roller on the arm, namely respectively: a configuration illustrated in FIG. 5 for which the working roll and the intermediate roll have maximum diameters (348 mm maximum diameter for the intermediate roll and 140 mm maximum diameter for the working roll), and according to a first position of the bearing support on the arm for which the axis of the rollers in the first row is at a distance of 180 mm from the pivot axis of the arm; two configurations illustrated respectively in FIGS. 6a and 6b, for which the working roll is at its maximum diameter and the intermediate roll at its nominal diameter (342.5 mm nominal diameter for the intermediate roll and 140 mm maximum diameter for the working roll), FIG. 6a illustrating the configuration according to the first position of the bearing support on the arm for which the axis of the rollers of the first row is at a distance of 180 mm from the pivot axis of the arm, FIG. 6b illustrating another configuration, after turning over of the bearing support on the arm, and according to a second position of the bearing support on the arm for which the axis of the rollers of the first row is at a distance of 172 mm from the axis of the pivot arm, a configuration illustrated in FIG. 7 for which the working roll is at its minimum diameter and the intermediate roll at its maximum diameter (348 mm maximum diameter for the intermediate roll and 120 mm minimum diameter for the working roll) and according to the first position of the bearing support on the arm for which the axis of the rollers in the first row is at a distance of 180 mm from the pivot axis of the arm, a configuration illustrated in FIG. 8 for which the working roll is at its minimum diameter and the intermediate roll at its maximum diameter (348 mm maximum diameter for the intermediate roll and 120 mm minimum diameter for the working roll) and according to the first position of the bearing support on the arm for which the axis of the rollers in the first row is at a distance of 180 mm from the pivot axis of the arm, two configurations illustrated respectively in FIGS. 9a and 9b for which the working roll is at its minimum diameter and the intermediate roll at its nominal diameter (342.5 mm nominal diameter for the intermediate roll and 120 mm minimum diameter for the working roll), FIG. 9a illustrating the configuration according to the first position of the bearing support on the arm for which the axis of the rollers in the first row is at a distance of 180 mm from the pivot axis of the arm, FIG. 9b illustrating another configuration according to a second position of the bearing support on the arm for which the axis of the rollers in the first row is at a distance of 172 mm from the pivot axis of the arm,

(3) FIG. 10 is a view of a configuration for which the working roll is at its minimum diameter and the intermediate roll at its minimum diameter (330 mm maximum diameter for the intermediate roll and 120 mm minimum diameter for the working roll) and according to the second position of the bearing support on the arm for which the axis of the rollers in the first row is at 172 mm from the pivot axis of the arm,

(4) FIG. 11 is a view illustrating a second embodiment of the invention for which an eccentric is provided between the articulation axis and said arm, and in which said adjustment of the dimension separating the axis of said support roll and the axis of said side support roller used during the readjustment step is carried out by a step of rotation of said eccentric,

(5) FIG. 12 is a view illustrating a third embodiment of the invention for which said adjustment of the dimension separating the axis of said support roll and the axis of said side support roller implemented during the readjustment step is performed by a step of modifying the position of said articulation axis on said axis support formed here by the chocks of the support roll, said step of modifying the position of said articulation axis on the chocks being obtained by rotating an eccentric provided between said articulation axis and the chocks,

(6) FIG. 13 is a schematic view of a fourth embodiment for which the assembly consisting of side support roller and bearing support is articulated via an arm on the Maes block intended for cambering the support roll, the assembly consisting of side support roller and bearing support being able to be moved in accordance with the movement of the Maes block and in which said adjustment of the dimension separating the axis of said support roll and the axis of said side support roller implemented during the readjustment step is performed by a step of modifying the position of said support roll with respect to the Maes block intended for cambering the support roll, carried out for example by turning the asymmetric chocks of the support roll through 180°.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

(7) Thus the invention relates to a rolling method adapted to a strip rolling mill comprising the following steps: a rolling, by a pair of working rollers WR with parallel axes, of said strip taken between said working rolls WR and travelling between the pair of working rolls, each of said working rolls having at least one generatrix of contact with the strip, a transmission, to said working rolls WR, of a rolling force substantially normal to the strip, by a pair of support rolls SR, said working rolls WR and said support rolls SR situated on the same side of the strip being in contact with each other along a common support generatrix in order to transmit said rolling force, a plane perpendicular to a direction of travel of the strip, in which at least one contact generatrix and the axes of said working rolls are situated, holding of each of said working rolls WR by a pair of side support rollers SSR, situated on either side of said perpendicular plane, each of the side support rollers SSR being able to exert, along a bearing generatrix of said working roll WR, a force maintaining the axis of the working roll WR in a given position with respect to a rolling cage of the mill and with respect to said side support rollers, support of each of said side support rollers by means of two rows formed by a plurality of rollers G mounted side by side, for maintaining the side support rollers SSR in a given position, support of each of the two rows formed by said plurality of rollers G, by means of a bearing support BS carrying the two rows, said bearing support being mounted pivotally on an articulation axis A1, parallel to the support roll SR, carried by an axis support AS, such as the chocks Ep of the support roll, or the Maes blocks MB intended for cambering the support roll, said axis support AS being fixed with respect to the axis of the support roll SR.

(8) The rolling mill may be a rolling cage comprising the two working rolls, the two support rollers and the two support rolls, each support roll being intermediate between said bearing roller and said working roll, namely a rolling-mill cage of the laterally supported sexto type.

(9) According to a possibility illustrated in accordance with FIGS. 1 and 12, said articulation axis A1 about which the bearing support BS is mounted is supported and mounted secured to two chocks Ep of the support roll SR (in other words the intermediate roll IR), the assembly consisting of intermediate roll IR, bearing supports BS and two of the side support rollers SSR, on either side of the perpendicular plane forming a self-supporting assembly able to be introduced into or removed from the cage by sliding the assembly in the direction of the rolls, typically referred to as a “cassette” or “insert”, and as known per se from the document WO 2015/011373.

(10) According to another possibility illustrated in FIG. 13, said articulation axis A1, about which the bearing support BS is pivotally mounted, is supported and mounted installed on a Maes block MB intended for cambering the intermediate roll IR, able to be moved vertically along the uprights of the cage and as known per se from the document WO 2011/107165.

(11) When the rolling method is implemented, the dimensions of a first interspace It1 defined between the side support roller SSR and the support roll SR and of a second interspace It2 defined between the strip ST and the assembly consisting of side support roller SSR and bearing support BS vary during rolling because of the reductions in diameters of the support roll and of the working roll.

(12) The reductions in diameter are caused by wear and planing of the rolls. Periodically, and in a known manner, the working rolls and the support rolls are removed from the cage: planing of the working roll is carried out, and less frequently planing of the intermediate roll, in order to restore the surface state thereof.

(13) The inventors observe that the mechanism supporting and positioning the side support rollers with a pivot position fixed with respect to the axis of rotation of the intermediate roll, and a fixed arm length (as in particular taught by the document WO 2011/107165 or WO 2015/011373) have drawbacks for some configurations of diameters of the intermediate roll and of the working roll: thus risks of interferences between the intermediate roll and the side support roller are observed, or a risk of obstruction of the passage opening for the jets spraying and lubricating the contact between intermediate roll and working roll, or obstruction of the jets for lubricating the rolling area.

(14) Thus, and in FIG. 3 depicting such a prior art and according to a configuration for which the diameter of the intermediate roll is maximum (355 mm) and the diameter of the working roll is minimum (120 mm), it is observed that the spraying jets are interrupted (on the right), the passage opening between the side support roller (right) and intermediate roll is so small that the jet J1 no longer passes through it, the cooling of the working roll and of the interface between intermediate roll and working roll being compromised. A very small clearance of 0.7 mm between the bearing support (on the right) and the intermediate roll is also observed, with risk of mechanical contact.

(15) Likewise in FIG. 4, for which the diameters of an intermediate roll at the minimum diameter and a working roll at the maximum diameter, it is observed that the distance between the metal strip and each bearing support (left) is small, with only 7.3 mm, representing a significant risk of contact.

(16) The invention advantageously makes it possible to avoid such mechanical interferences by using a readjustment step for which the dimension of said first interspace It1 and of the second interspace It2 is adjusted by implementing an adjustment of the dimension separating the axis A.sub.SR of said support roll SR and the axis A.sub.SSR of said side support roller SSR defining, with the support roll, said first interspace It1.

(17) This readjustment step can advantageously be implemented when there is an interruption of the rolling, for example simultaneously with an interruption of rolling for planing of the working roll and/or of the support roll.

(18) This readjustment step consists in adjusting the dimension separating the axis of said support roll SR and the axis of said side support roller SSR so that the dimension of the first interspace It1 is at least equal to a lower limit Δmin1 and the dimension of the second space It2 is at least equal to a lower limit Δmin2, whatever the configurations, namely as long as: the diameter of the working roll WR is between a minimum diameter and a maximum diameter, the diameter of the support roll SR is between a minimum diameter and a maximum diameter.

(19) This lower limit Δmin1 and this lower limit Δmin2, which may be equal or distinct, may be greater than or equal to 5 mm.

(20) FIGS. 5 to 10 illustrate the various possible configurations of a rolling-mill cage of the laterally supported sexto type with cassette, as the prior art shown in FIGS. 1 to 4.

(21) These FIGS. 5 to 10 show the support roll SR, which is the intermediate roll IR, and which transmits the rolling force to the working roll WR. The support roll SR is conventionally articulated at its ends in chocks.

(22) On either side of the clamping plane, each side support roller SSR is held by two rows of rollers G of a bearing support BS mounted pivotally via an arm AR on the articulation axis A1 on an axis support formed by the chocks of the support roll SR. The support roll SR with its chocks, the arms AR, the bearing supports BS and the pair of side support rollers form a self-supporting assembly that can be removed when the cage is opened, in a way known per se from the prior art.

(23) According to this embodiment, said bearing support BS is fixedly mounted removably on an arm AR, with an adjustable position on the arm, said arm AR itself being articulated on said articulation axis A1, parallel to said support roll, providing the pivoting of said bearing support about said articulation axis A1.

(24) Remarkably, and according to this embodiment, said adjustment of the dimension separating the axis of said support roll SR and the axis of said side support roller SSR implemented during the readjustment step is performed by a step of modification of the position of said bearing support BS on the arm AR.

(25) More particularly, provision can be made for a removable fixing means between said bearing support BS and said arm AR comprising a groove/key positive-location system 1, said key and a groove carried respectively by said bearing support BS and said arm AR, or vice versa.

(26) As can be seen in FIG. 5, said key or the groove carried by the bearing support is remarkably offset in the longitudinal direction of the arm AR, with respect to the plane, parallel to the axis of the bearing roller, passing through the median line Md to the segment, perpendicular to the side support roller, joining the two axes of the two rows of rollers G.

(27) The adjustment of the dimension separating the axis of said support roll and the axis of said side support roller implemented during the readjustment step is carried out by a step of turning over said bearing support BS on the arm.

(28) This readjustment step carried out by turning over said bearing support BS on the arm AR is illustrated by way of example in FIGS. 9a and 9b.

(29) The two configurations illustrated respectively in FIGS. 9a and 9b are configurations for which the working roll is at its minimum diameter and the intermediate roll at its nominal diameter (342.5 mm nominal diameter for the intermediate roll and 120 mm minimum diameter for the working roll).

(30) FIG. 9a illustrates the configuration according to the first position P1 of the bearing support on the arm for which the axis of the rollers in the first row is at a distance of 180 mm from the articulation axis A1 of the arm, whereas FIG. 9b illustrates another configuration according to a second position P2 of the bearing support on the arm for which the axis of the rollers in the first row is at a distance of 172 mm from the pivot axis of the arm.

(31) The passage from the first position P1 of the bearing support to the second position P2 of the bearing support is obtained by simple turning of said bearing support BS through 180° on the arm, when rolling is interrupted.

(32) This turning over effects a modification of the dimension separating the axis A.sub.SR of said support roll SR and the axis A.sub.SSR of said side support roller SSR defining, with the support roll, said first interspace It1, and in this case a reduction in the dimension separating the axis A.sub.SR of said support roll SR and the axis A.sub.SSR of said side support roller SSR (from FIG. 9a to FIG. 9b).

(33) A readjustment (a modification) of the dimension of said first interspace It1 and of the second interspace It2 is then observed: in FIG. 9a, and according to the first position P1 of the bearing support BS on the arm, the first interspace between the side support roller SSR (left) and the support roll (SR) is 17 mm and the first interspace between the side support roller SSR (right) and the support roll SR is 15.1 mm, on the one hand, and the second interspace between the strip and the assembly consisting of bearing support and side support roller (left) is 8.7 mm and the second interspace between the strip and the assembly consisting of bearing support and side support roller (right) is 8.9 mm, in FIG. 9b, and according to the second configuration P2 of the bearing support BS on the arm, the first interspace between the side support roller SSR (left) and the support roll SR is 10.5 mm, and the first interspace between the side support roller SSR (right) and the support roll SR is 9 mm, on the one hand, and the second interspace between the strip and the assembly consisting of bearing support and side support roller (left) is 18 mm, the second interspace between the strip and the assembly consisting of bearing support and side support roller (right) is 16.3 mm.

(34) It will be noted that, at this nominal diameter of the support roll SR (here in this case equal to 342.5 mm) and whereas the working roll is at minimum diameter (here in this case 120 mm), the most critical case in terms of risks of mechanical interference, it is possible to proceed with the readjustment step, keeping, before (FIG. 9a) and after (FIG. 9b) the readjustment step, a value of the first interspace It1 and an interspace value It2 sufficient to prevent risks of mechanical interference.

(35) It will be noted that this change to be made by turning over the bearing support when the support roll is at its nominal diameter (342.5 mm) but the working roll is at its maximum diameter (140 mm) does not pose any difficulty in that the first interspace It1 and the second interspace It2 have values that are even more comfortable in terms of risks of mechanical interference, and as can be seen in FIGS. 6a and 6b.

(36) As can be understood from FIGS. 5 to 10: the first rolling configuration (first position P1 of the bearing support on the arm for which the axis of the rollers in the first row is at a distance of 180 mm from the articulation axis A1 of the arm) can be kept without risk of mechanical interference as long as the diameter of the support roll SR is between the maximum diameter and the nominal diameter and whatever the diameter of the working roll lying between the minimum diameter and the maximum diameter, and as can be understood more particularly from FIGS. 6a and 9a, the second rolling configuration (second position P2 of the bearing support on the arm for which the axis of the rollers in the first row is at a distance of 172 mm from the articulation axis A1 of the arm) can be kept without risk of mechanical interference, as long as the diameter of the support roll SR is between the nominal diameter and the minimum diameter and whatever the diameter of the working roll lying between the minimum diameter and the maximum diameter, and as can be understood more particularly from FIGS. 6b and 9b.

(37) The problems of mechanical interferences and obstruction of jets identified in FIGS. 3 and 4 representing the prior art are solved: a comparison between FIG. 3 (prior art) and FIG. 8 according to the invention both representing the case where the diameter of the support roll is at a maximum, the diameter of the working roll minimum, shows that the problems of mechanical interference and jet obstructions are solved, a comparison between FIG. 4 (prior art) and FIG. 10 (according to the invention) both representing the case where the diameter of the support roll is minimum, the diameter of the working roll maximum, shows that the problems of risk of mechanical interference are reduced.

(38) Thus and in general terms and according to an advantageous embodiment, the diameter of the support roll SR being between a maximum diameter and a minimum diameter, a method in which a nominal diameter is defined, less than the maximum diameter and greater than the minimum diameter and wherein: a first rolling configuration is maintained (without readjustment step) as long as the diameter of the support roll is between the maximum diameter and the nominal diameter, a second rolling configuration is obtained, when the support roll is at the nominal diameter, to within a tolerance, by performing the readjustment step with reduction in the dimension separating the axis A.sub.SR of said support roll SR and the axis A.sub.SSR of said side support roller SSR, said second configuration obtained by the readjustment step as long as the diameter of the support roll is between the nominal diameter is maintained as long as the diameter of the support roll is between the nominal diameter and the minimum diameter.

(39) It will be noted that the invention also makes it possible to considerably reduce the risks of mechanical interference between the strip and the assembly consisting of bearing support and side support roller on the one hand, or between the assembly consisting of bearing support and side support roller and the support roll on the other hand.

(40) As can be seen in FIGS. 5 to 10, and keeping the interspace It1 between the support roll and the side support roller greater than or equal to a lower limit Δmin1, the invention also makes it possible to provide optimise cooling of the contact between support roll SR and working roll by direct spraying of the working roll, throughout operation, whatever the diameter of the working roll and the diameter of the support roll, and without risk of complete interruption of the jet during such operation.

(41) Advantageously, the rolling mill may thus have at least spray nozzles SN1, SN2 allowing cooling by spraying of at least one jet of fluid on at least part of the strip ST and at least part of said rolls and in which method a cooling step is implemented, comprising at least one direct spraying of at least part of the working rolls WR, on either side of said plane perpendicular to the travel direction of the strip, said nozzles SN1, SN2 being configured to: produce a jet J1 directed towards the working roll WR, from at least one side of the plane perpendicular to the direction of travel, the jet passing through said first interspace It1 between the side support roller SSR and the support roll SR, before reaching said working roll WR, and/or produce a jet J2 directed towards the working roll WR, from at least one side of the plane perpendicular to the direction of travel, passing through the interspace between the strip and the side support roller, before reaching said working roll and/or the strip.

(42) For each working roll, a direct spraying can thus be implemented on either side of the clamping plane. The nozzles SN1 and SN2 may be carried by the arm A.R. and/or the bearing support B.S.

(43) FIGS. 5 to 10 show an example for which the readjustment step is performed by changing the position of the bearing support BS on the arm AR, and in order to modify (adjust) the dimension separating the axis A.sub.SR of said support roll SR and the axis A.sub.SSR of said side support roller SSR.

(44) Other technical solutions can be envisaged without departing from the scope of the invention, and still with the objective of modifying (adjusting) the dimension separating the axis A.sub.SR of said support roll SR and the axis A.sub.SSR of said side support roller SSR.

(45) According to another embodiment, said bearing support BS being fixedly mounted on an arm AR itself articulated on said articulation axis A1 parallel to said support roll providing the pivoting of said bearing support about said articulation axis A1, and in said adjustment of the dimension separating the axis of said support roll and the axis of said side support roller implemented during the step of readjustment is performed by a step of adjusting the position of said articulation axis A1 on the support arm AR.

(46) For example, an eccentric Ex1 may be provided between the articulation axis A1 and said arm AR, and wherein the adjustment of the dimension separating the axis A.sub.SR of said support roll SR and the axis A.sub.SSR of said side support roller SSR implemented during the readjustment step is performed by a step of rotation of said eccentric Ex1.

(47) Such an embodiment is illustrated in FIG. 11, illustrating respectively in solid lines and in broken lines the change in position of the arm and of the bearing support in two positions of the eccentric Ex1. It is observed that, when the eccentric Ex1 is rotated, the position of the axis A1 remains unchanged, whereas the arm AR and the bearing support BS move away from the axis of the support roll SR.

(48) According to another embodiment, said articulation axis A1 around which the bearing support BS is mounted is supported and mounted on said axis support AS and in which method said adjustment of the dimension separating the axis A.sub.SR of said support roll SR and the axis A.sub.SSR of said side support roller SSR implemented during the readjustment step is performed by a step of modifying the position of said articulation axis A1 on said axis support AS.

(49) For example, said step of modifying the position of said articulation axis on said axis support AS is obtained by adding or removing shims between the axis support and said articulation axis (example not illustrated), or said step of modifying the position of said articulation axis on said axis support is obtained by rotating an eccentric Ex2 provided between said articulation axis A1 and said axis support AS.

(50) This latter embodiment with eccentric Ex2 is illustrated in FIG. 12, illustrating respectively in solid lines and in broken lines the change in position of the arm and of the bearing support in two positions of the eccentric Ex2. According to this schematic example, the support roll SR is mounted rotatably at chocks Ep, said articulation axis A1 being fixed at the ends thereof to two chocks of the support roll that constitute the axis support AS. An eccentric Ex2 is provided between each end of the articulation axis A1 and the chock Ep. As can be seen in FIG. 12, the rotation of the eccentric Ex2 makes it possible to modify the position of the articulation axis A1 on the axis support AS.

(51) Again, and according to a fourth possible embodiment, said support roll SR is supported at the ends thereof by chocks Ep, and in which method said adjustment of the dimension separating the axis A.sub.SR of said support roll SR and the axis A.sub.SSR of said side support roller SSR implemented during the readjustment step is performed by a step of modifying the position of the axis A.sub.SR of said support roll with respect to the Maes blocks MB intended for cambering the support roll.

(52) For example, and according to the embodiment illustrated in FIG. 13, the support roll SR mounted rotatably on chocks Ep, each of the chocks being in engagement with a Maes block MB. Each bearing support BS is mounted on an arm AR articulated on the axis A1 on the axis support AS formed here by the Maes block MB.

(53) It should also be noted that the chocks Ep are asymmetric, in that they make it possible to obtain two positions of mounting the support roll, with offset of the axis A.sub.SR of the support roll depending on whether the chock is mounted in a first mounting direction in the Maes block, or in the second mounting direction, obtained by turning over the chock Ep.

(54) According to this embodiment, the adjustment during the readjustment step is obtained by turning over the block through 180°.

(55) The invention also relates to a mill for rolling a strip ST suitable for implementing the method. Said rolling mill includes at least one cage comprising: a pair of working rollers WR with parallel axes, between which the strip ST travels, each of said working rolls having at least one generatrix for contact with the strip, a plane perpendicular to a direction of travel of the strip, wherein at least one contact generatrix and said axes of said working rolls WR are situated, a pair of support rolls SR, with axes parallel to the plane of the strip and situated on either side of said strip, said support rolls and working rolls situated on the same side of the strip being in contact with each other along a common support generatrix in order to transmit to the working rolls a rolling force substantially normal to the strip, two pairs of side support rollers with parallel axes, said rolls in the same pair being situated symmetrically on either side of one of said working rolls, in a plane parallel to the strip, so that each of the side support rollers SSR in the same pair is able to transmit, along a bearing generatrix of said working roll WR, a force allowing holding in a given position relative to the support roll SR, a support of each of said support rollers by means of two rows formed by a plurality of support rollers G mounted side by side, making it possible to maintain the side support rollers SSR in a given position, a support of each of the two rows formed by said plurality of support rollers, by means of a bearing support BS carrying the two rows of rollers, said bearing support BS being mounted pivotally on an articulation axis A1, parallel to the support roll, carried by an axis support AS, fixed with respect to the axis of the support roll, such as the chocks Ep of the support roll, or the Maes blocks MB intended for cambering the support roll.

(56) Such a mill comprises, during the rolling of the metal strip, a first interspace It1 defined between the side support roller SSR and the support roll S and a second interspace It2 defined between the strip ST and the assembly consisting of side support roller SSR and bearing support BS liable to vary during rolling because of reductions in diameters of the support roll and of the working roll caused by wear or planing of the cylinders.

(57) According to the invention, said mill comprises an adjustment device configured to adjust the dimension of said first interspace It1 and of the dimension of the second interspace It2 by implementing an adjustment of the dimension separating the axis A.sub.SR of said support roll SR and the axis A.sub.SSR of said side support roller SSR defining, with the support roll, said first interspace It1.

(58) The mill may comprise a device configured for cooling by spraying at least one jet of fluid on at least one part of the strip and at least one part of said rollers, comprising at least one nozzle system with nozzles SN1, SN2 configured to: produce a jet J1 directed towards the working roll, from at least one side of the plane perpendicular to the travel direction, the jet passing through a first interspace It1 between the side support roller SSR and the support roll SR, before reaching said working roll WR, and/or produce a jet J2 directed towards the working roll, from at least one side of the plane perpendicular to the direction of travel, passing through the interspace between the side support roller SSR and the strip ST, before reaching said working roll and/or the strip.

(59) According to one embodiment, the adjustment device comprises said bearing support BS that is fixedly mounted removably on an arm AR, with an adjustable position on the arm, said arm itself being articulated on said articulation axis parallel to the support roll SR providing the pivoting of said bearing support BS about said articulation axis. The adjustment device is configured so that the adjustment of the dimension separating the axis A.sub.SR of said support roll SR and the axis A.sub.SSR of said side support roller SSR is performed by modifying the position of said bearing support BS on the arm AR.

(60) For example, and according to the example in FIGS. 5 to 15, the adjustment device comprises a removable fixing means between said bearing support and said arm comprising a groove/key positive-location system 1, said key and said groove carried respectively by said bearing support and said arm, or vice versa, said key or the groove carried by the bearing support BS being offset in the longitudinal direction of the arm, with respect to the plane, parallel to the side support roller, passing through the median line Md to the segment perpendicular to the side support roller joining the two axes of two rows of rollers. The adjustment device is configured so that said adjustment of the dimension separating the axis of said support roll and the axis of said side support roller is carried out by turning over said bearing support BS.

(61) According to another embodiment illustrated by way of indication in FIG. 11, said bearing support BS is mounted fixedly on an arm AR itself articulated on said articulation axis A1 parallel to said support roll providing the pivoting of said bearing support BS about said articulation axis, and wherein the adjustment device is configured so that the adjustment of the dimension separating the axis A.sub.SR of said support roll SR and the axis A.sub.SSR of said side support roller SSR is performed by adjusting the position of said articulation axis A1 on the arm AR.

(62) Said adjustment device may comprise an eccentric Ex1 provided between the articulation axis A1 and said arm AR, said adjustment device being configured so that said adjustment of the dimension separating the axis A.sub.SR of said support roll SR and the axis A.sub.SSR of said side support roller SSR is performed by a step of rotating said eccentric Ex1.

(63) According to another embodiment illustrated by way of indication in FIG. 12, said articulation axis A1 about which the bearing support BS is mounted is supported and mounted on an axis support AS and wherein the adjustment device is configured so that the adjustment of the dimension separating the axis AS of said support roll SR and the axis A.sub.SSR of said side support roller SSR is performed by modifying the position of said articulation axis A1 on said axis support AS.

(64) The adjustment device may then comprise shims, said adjustment device being configured so that the modification of the position of said articulation axis on said axis support is obtained by adding or removing shims between the axis support and said articulation axis.

(65) Alternatively, said adjustment device comprises the eccentric Ex2 provided between said articulation axis and said axis support AS: said adjustment device is configured so that modification of the position of said articulation axis A1 on said axis support AS is obtained by rotating the eccentric Ex2.

LIST OF COMPONENTS

(66) A1. Articulation axis (between the bearing support BS and the axis support AS) A.sub.SR. Axis of the support roll A.sub.SSR. Axis of the side support roller AR. Arm AS. Axis support BS. Bearing support Ep. Chock Ex1, Ex2. Eccentrics G. Rollers (bearing support) IR. Intermediate roll (support roll) It1. First interspace between the side support roller and the support roll It2. Second interspace between the assembly consisting of a side support roller and bearing support and the strip J1. First jet J2. Second jet MB. Maes block Md. Median line SR. Support roll SSR. Side supportroller ST. Strip WR. Working rolls 1. Groove/key positive-location system