EP3445506A1

EP3445506A1 - Method for changing the rolls on a rolling mill

Info

Publication number: EP3445506A1
Application number: EP17717717.7A
Authority: EP
Inventors: Benoît BROEKS; Aymeric DELANOY
Original assignee: Fives DMS SA
Current assignee: Fives DMS SA
Priority date: 2016-04-18
Filing date: 2017-04-14
Publication date: 2019-02-27
Anticipated expiration: 2037-04-14
Also published as: ES2839699T3; US11358193B2; FR3050128B1; EP3445506B1; FR3050128A1; CN109153054A; WO2017182406A1; US20190091744A1; CN109153054B

Abstract

The invention relates to a method for changing the rolls on a rolling mill for rolling a metal strip, which is carried out in an installation having a rolling mill of the Quarto stand type, comprising two working rolls (3, 4), one lower and one upper, defining the nip through which the sheet passes, and two support rolls (5, 6), respectively one lower and one upper, intended to bear respectively against the working rolls on the opposite side to the side of the nip. According to the invention, the installation comprises a system for extracting the working rolls and the support rolls provided, on the drive side of the said rolling mill and comprising: - an actuator (70) configured to push the rolls out of the roll stand of the rolling mill when the rolls are being extracted, – a coupling head (8), secured to the said actuator (70), situated in a position of opening of the roll stand (2), comprising - first coupling means configured to drive the chock (40) or the end of the lower working roll (4), on the rolling-mill drive side, - second coupling means configured to drive the chock of the lower support roll (6), on the rolling-mill drive side. Advantageously, the first coupling means and the second coupling means of the said extraction system are configured in such a way as to allow successive extractions of the working rolls (3, 4) and then of the support rolls (5, 6) from the roll stand (2) using the one same actuator of the extraction system. The invention also relates to a rolling mill installation for carrying out the method of the invention.

Description

METHOD FOR CHANGING CYLINDERS OF A ROLLING MILL

The content of priority application FR 16 53 411 of 18 April 2016 is incorporated by reference. The invention relates to a method of changing the rolls of a rolling mill for a metal strip, and a rolling mill comprising a rolling mill and a cylinder change system advantageously allowing the implementation of the method according to the invention.

The field of the invention is that of Quarto cage mills which find particular application, for example in annealing lines, or galvanizing lines, or else, offline mills, reversible or non-reversible, for metal band . The mill according to the invention has a particular application, especially after annealing of the strip, to make a skin pass, often for the purpose of removing the elastic bearing from the metal strip to print a roughness and / or improve the brightness and / or improve the flatness.

A Quarto cage mill has a holding cage comprising two pairs of uprights, at both ends of the cage between which are provided four cylinders with parallel axes, namely two working rolls, lower and upper, defining the air gap the strip to be rolled, as well as two support rolls, upper and lower, respectively bearing on the working rolls, on the opposite side to that of the air gap. The motorization of the cylinders is provided on one side of the cage, the other side, said operator side being the one where the maintenance operations are performed, in particular the cylinder change operations through the access window present between the two uprights of the cage on this operator side. In such rolling mills, each support or working cylinder is rotatably mounted at its ends on chocks, by means of bearings, for example bearings or hydrostatic bearings. These chocks are supports that can be moved in a direction parallel to the clamping plane, between the two amounts of the cage.

A rolling mill of the Quarto type comprises means for applying a clamping force between the chocks of the support rolls, in the form of two hydraulic cylinders, often at the lower end of the cage, bearing respectively on the two chocks of one of the support cylinders, often inferior. When retracted, these two hydraulic cylinders allow the opening of the cage, namely the separation of the upper rollers (upper support cylinder and working roll) with respect to the lower rolls (lower support roll and lower work roll) , and in a position where these can be extracted from the cage.

The chocks of the work rolls, and the chocks of the support rollers are thus mounted sliding in a direction parallel to the clamping plane, so as to allow the opening of the cage or its closure, or facilitate the operations of maintenance and disassembly. For this purpose, each chock typically comprises two sliding plates, parallel and opposite, on either side of the axis of rotation of the cylinder, and cooperating with sliding plates secured to the uprights and parallel to the latter, at the level of on both sides of the window. These sliding plates do not, however, ensure the blocking of the chocks (and their cylinder) along the axis of the supported cylinder.

In the field of rolling mills, this blocking of the chocks of the cylinder along the axis of the cylinder is called "tamping" of the chocks. In a Quarto cage mill, the system for clamping the chocks of the working or bearing cylinders comprises, typically for each chock, two vertical grooves of the opposite chocks located on either side of the axis of rotation. cylinder, and two associated locking members respectively integral with the uprights, movable horizontally. Each locking member can move from a locking position in which the locking member penetrates the vertical groove, to an unlocked position in which the locking member is retracted out of this groove. In the locking position, the locking member, secured to the upright, prevents the displacement of the chock along the axis of the cylinder, while allowing the sliding of the chock along the vertical axis of the uprights, by moving the the locking member along the vertical groove of the chock.

To allow the change of the working cylinders and the support rollers, it is necessary to open the rolling mill, by retracting the clamping jacks, and to unlock the clamming system. It is only after these two actions that the cylinders and their chocks can be extracted from the roll stand.

The support cylinders and working cylinders of the Quarto type rolling mills of the state of the art are extracted from the holding cage, through the access window on the operator side, by means of two independent extraction systems. , in parallel, superimposed one above the other, located on the side of the motorization of the rolling mill, namely:

a first extraction system comprising an actuator, typically a hydraulic jack, the stroke of which is sufficient to allow the extraction of the working rolls from the holding cage, by a thrusting action and displacement of the working roll following its longitudinal axis, and

a second extraction system, independent, comprising another actuator, typically another hydraulic cylinder, whose stroke allows extraction of the support cylinders from the holding cage, by a thrust action and displacement of the cylinder; support along its longitudinal axis. Once extracted from the mill, these two extraction systems then allow to insert new cylinders (respectively the work rolls and the support rolls) in the roll stand of the rolling mill.

According to the findings of the Applicant, there is a need, in Quarto cage mills, for a method of changing the rolls of the mill which would significantly reduce the cost of the rolling mill.

However, it is known from the prior art of WO03 / 099479A1 a Quarto cage rolling installation equipped with an extraction system which comprises a spotted actuator 7, in this case a cylinder, substantially horizontal, provided with a coupling head comprising two arms 17a, 17b superimposed, respectively arranged at the level of the upper working cylinder 2a and the lower working cylinder 2b. Hydraulic (or electrical) clamps, identified 18, are associated with these two arms.

The document WO03 / 099479A1 further discloses a method for extracting the rolls, which extracts the work rolls marked 2a and 2b, but also the extraction of the support rollers 3a, 3b using only the running actuator horizontal actuator marked 7 for the thrust of the work rolls out of the cage, then for the thrust of the support rollers out of the cage.

The process for extracting the four cylinders is as follows, and is decomposed in two stages, first with the extraction of the working rolls and then with the extraction of the support rolls. In the open position of the rolling mill stand, the two clamps (hydraulic or electrical) first make it possible to simultaneously grasp the two ends of the work rolls marked 2a and 2b, and then the actuator 7 identified is used to push for simultaneously extracting the two working rolls 2a and 2b, which are then extracted from the roll stand, and while the support rolls 3a and 3b are still present in the stand.

For the exit of the support cylinders, a support equipment (marked 11) is used which is inserted into the roll stand, arranged between the upper support roll and the lower support roll. Once this support equipment 11 and the upper support cylinder 3a rest on the lower support cylinder 3a, the support equipment 11 is connected to the actuator 7. For this purpose, the upper clamp 18 of the upper arm (17a ) engages with a specific part 19 of the support equipment 11. The stroke of the actuator is then used to exit the lower support cylinder assembly 3b / support equipment 11 / lower support cylinder, in one piece .

According to the findings of the Applicant, the installation of this anteriority however has certain disadvantages, and in particular:

- the need to insert the support equipment marked 11 directly in the inter-space between the upper bearing cylinder 3a and the lower bearing cylinder 3b (then present in the roll stand), which requires equipment handling dedicated to this operation, - the use of an extraction system which comprises not only a spotted actuator 7, whose horizontal stroke is used to push the cylinders out of the cage, but also two dedicated actuators (hydraulic clamps or electric) respectively for the two arms, and in order to grasp both ends of the two working rolls, which strike the cost of installation. Document US 2002/0078728 still discloses a Quarto cage rolling mill installation and a method for changing the work rolls and the support rollers used in such an installation.

The extraction system comprises a single actuator (marked 54) with a horizontal stroke, provided with a coupling head (a marked hook 54a) which makes it possible to pull out all the cylinders (working and support), and in an illustrated sequence of Figures 6 (A) through 6 (D).

FIG. 6 (A) illustrates the step of extracting the two working rolls (jointly) by the actuator pushing action 54. Successively, at this extraction, the lower support roll 53 is lifted by cylinders 16 , allowing the setting of the chock of the lower support cylinder 54 with the hook 54a of actuator 54 horizontal. The same actuator 54 with a horizontal stroke is then used to release the lower support cylinder 53, and while the upper support cylinder is still present in the roll stand.

FIG. 6 (B) illustrates the next step for positioning a support equipment, marked 59 ("roll changing stool"), resting on the chocks of the lower bearing cylinders (then out of the cage), before inserting the assembly in the roll stand, namely the lower support roll and the support equipment by the pulling action of the actuator 54, and as shown in Figure 6 (C).

The upper support cylinder is then lowered on the support equipment 59, supported by its chocks, the actuator 54 is then used for the joint thrust of the assembly comprising the lower support cylinder, the support equipment and the upper support cylinder (superimposed).

Thus, the extraction method implemented in this prior art US 2002/0078728 uses as the document WO 03 / 099479A1 a support equipment ("rolling changing stool") comparable to the equipment identified in the prior art WO03 / 099479A1 the joint output of the upper and lower bearing rolls.

According to the findings of the Applicant, the method previously described in this prior art US 2002/0078728 is advantageous compared to that of WO03 / 099479A1 in that the horizontal actuator identified 54 is used, as well as the lower bearing cylinder (temporarily extracted) to allow the insertion of this equipment in the roll stand, and as shown in FIGS. 6 (B) and 6 (C), and contrary to the document WO 03/099479A1 which requires insert this support equipment directly between the support rolls present in the roll stand. According to the findings of the Applicant, however, the installation of this prior art US 2002/0078728 has certain disadvantages, and in particular the need to provide in the roll stand of the support rails of the lower support cylinder 53 of variable level, called " up-and-down rails 15 ", operable at the descent or the climb by means of cylinders 16. In the low position of the rails, the hook 54a of the horizontal actuator is aligned with the complementary hook of the chock 57 of the cylinder lower working, and as shown in Figure 6 (A), allowing the actuator to be engaged with the work rolls to allow its extraction.

In their high position, the support rails of the lower support cylinder are aligned with the marked rails 18 allowing the output of the lower support cylinder. Raising the rails from the low position to the high position still allows the hook 54a to engage with a complementary hook of the chock of the lower support cylinder.

In other words, and for the extraction of all the cylinders (the work rolls and the support rolls), the actuator 54 (horizontal stroke) for the thrust of the rolls must necessarily be combined with a system of rails, for supporting the chocks of the lower support cylinder and whose jacks marked 16 to change the level of the lower support cylinder (and thus the lower working cylinder bearing on the latter) to allow the same hook 54a of the horizontal actuator to respectively engage with a hook 54b of the chock of the work roll (in the low position of the rails 15 illustrated in Figure 6 (A), and engaged with a hook 24 of the chock of the lower bearing roll (in the upper position of rails shown in Figs. 6 (B) to 6 (C)). The present invention meets this objective by proposing a cylinder changing method which advantageously allows the use of an extraction system using a single actuator to extract all the rolls of the rolling mill.

More particularly, the object of the present invention is such a single actuator method whose coupling head can be linked, firstly to the chock of a working cylinder, then in a second time to the chock of a support cylinder, to allow the extraction of all the cylinders (namely the working cylinders and the support cylinders) by limiting the costs of the installation necessary for these operations, and by comparison in the state of the art disclosed in US 2002/0078728.

Another object of the present invention is to provide such a rolling mill comprising a rolling mill, and a cylinder extraction system, lower cost compared to the state of the art facilities, particularly suitable for the implementation implementation of the method. Other advantages of the invention will become apparent during the description which is given only as an indication and which is not intended to limit it.

Also the invention relates firstly to a method of changing the rolls of a metal strip rolling mill, implemented in an installation having:

a rolling mill comprising: a holding cage,

- A set of superimposed cylinders with substantially parallel axes comprising two lower and upper working rolls, defining the passage gap, and two respectively lower and upper support rolls for respectively bearing on the working rolls of the opposite side. to that of the passing air gap,

each cylinder having two rotatably mounted ends, each on a bearing carried by a chock, guiding means between the chocks of the rolls and the holding cage along the clamping plane,

- Means for applying a clamping force between the chocks of the bearing cylinders, comprising hydraulic cylinders, - a clamping system of the chocks of the cylinders, ensuring the locking of the chocks relative to the holding cage, following the axis of the cylinder, while allowing the sliding of the chocks along the guide means, according to the clamping plane,

means for motorizing the support rolls, on one side of the roll stand,

a system for extracting the work rolls and support rolls provided, on the motorization side of said rolling mill, comprising:

an actuator configured to push the rolls out of the roll stand while the rolls are being pulled out, or on the contrary to pull the rolls into the stand during insertion of the rolls,

a coupling head integral with said actuator, located in the open position of the holding cage, at an intermediate height level between the lower working roll and the lower supporting roll, movable in a direction parallel to the rolls; from a first retracted position for which the coupling head is located motor side, to a second extended position for which the coupling head having passed through the holding cage is located operator side, said coupling head comprising:

first coupling means configured to drive the chock or the end of the lower working roll, on the motorization side of the rolling mill, second coupling means configured to drive the chock of the lower support roll, on the motor side of the rolling mill. , having a retracted state in which they do not carry the chock of the lower support cylinder and an expanded state in which they push the chock of said lower bearing cylinder,

and in which the chocks of the upper and lower work rolls have connecting means, on the operator side, providing a mechanical connection between these chocks on the operator side, and in which the work rolls and the work rolls are extracted. support, after opening of the holding cage of said rolling mill during which the lower work roll and the lower support roll are spaced apart from the upper work roll and the upper support roll, while the metal band is present along the scroll plane of said rolling mill by the implementation of the following successive steps:

- A first extraction step during which are extracted the upper working cylinder and the lower working cylinder, by a thrust action of said actuator on the chock of the lower working cylinder, motor side, the coupling head passing from the first retracted position to the second extended position, said upper working cylinder being driven together with the lower working cylinder by the mechanical connection created, on the operator side, between the chocks of the lower and upper work rolls, said second means of coupling of the coupling head being in said retracted state where they do not cause the chocks of the support cylinders during this thrust action,

- A return step during which the coupling head is returned from the second deployed position towards the motor side to the first retracted position, - a second extraction step during which is extracted the support cylinder lower out of the holding cage by a pushing action of said actuator on the chock of the lower support cylinder on the motor side, the coupling head passing from the first retracted position to the second deployed position, said second coupling means being in said expanded state for driving the thrust of the chock of said lower bearing cylinder, a positioning step during which a support equipment is positioned on the lower support roll, the lower part of which bears against the chocks of the lower support roll, and whose upper part is intended to serve as support for the chocks of the upper support cylinder, said support equipment being insertable in the holding cage,

an insertion step during which the lower support roll and said support equipment are inserted into the holding cage, by the traction action caused by the return of the coupling head towards the drive side since the second deployed position to the first retracted position, said support equipment having a clearance traversed by the metal strip when inserted into the holding cage,

a deposition step during which the upper support roll is deposited on the upper part of the support equipment, by a descent action of said upper support roll, a third extraction step during which is extracted the assembly comprising the lower support cylinder, the support equipment, and said upper support cylinder by a thrust action of said actuator on the chock of the lower support cylinder, motor side.

According to a notable feature of the invention, passing the second coupling means of the retracted state in which they do not lead the chock of the lower support cylinder to the deployed state in which they lead to thrust l the chock of said lower support cylinder by a manual action on said second coupling means, in succession to said first extraction step, the coupling head being in said second extended position, accessible on the operator side of said rolling mill, and prior to said step back.

Also, and according to the invention, the coupling head can be coupled to the working roll (and while the second coupling means are in the retracted state and do not drive the lower support roll) to allow the implementing the first step of extracting the work rolls and then being coupled to the lower support roll for the implementations of the following steps, this change being made manually, in other words without the use of an actuator (such as the jacks marked 16 as in US 2002/0078728) to allow this change of coupling.

In the invention, the change of coupling of the coupling head (from the retracted state of the second coupling means to the deployed state) is obtained by a manual action of an operator (and therefore without the use of a electric actuator, hydraulic pneumatic or other that strike the cost of installation).

For example, and according to one embodiment, the second coupling means comprise at least one movable element, articulated to the frame of the coupling head, suitable for cooperating with the thrust with the chock of the lower bearing cylinder, which on the one hand, in the retracted state of the second coupling means, is raised and locked in a retracted position where said movable element does not engage with the chock, of the lower support cylinder, motor side, and which on the other hand, in the deployed state of the second coupling means is in an extended position where said movable member projects downward under the action of gravity, and wherein said movable member is configured in said deployed position to engage with a projecting portion on the upper face the chock of the lower support cylinder on the motorization side, and in which:

during said step of returning the coupling head, said passage of the coupling head from the second deployed position to the first retracted position causes the projection to engage against the movable element, which pivots about its articulation under the action of the projecting part, to escape said projecting part, before returning, under the effect of gravity, in a position in which said movable element projects downwards, on the other side of the protruding part during the second extraction step, said movable element abuts against said projecting part, on the other side of the projecting part, under the actuator pushing action and so as to allow said cylinder to exit lower support. According to one embodiment of the method:

the rolling mill holding cage comprises support rails on which the chocks of the upper and lower work rolls rest, in the open position of the holding cage, said support rails guiding the work rolls and their chock during extraction of the cylinders in said holding cage,

said rolling installation comprises a support carriage having supporting rails suitable for supporting and guiding the chocks of the lower and upper working rolls, which, in a relative position of the carriage with respect to the rolling mill, extend the support rails of the rolling mill. , and in such a way that the lower and upper work rolls are loaded onto the support carriage when the coupling head reaches said second deployed position in the first extraction step.

According to optional features of the process, taken alone or in combination:

the first coupling means comprise a hook rigidly secured to the coupling head intended to engage with a corresponding hook integral with the motor-side end of the lower work roll, and suitable for exerting a thrust force on the work roll lower during the first extraction step and the passage of the coupling head of the first retracted position to the second deployed position and to exert a traction force on the working cylinder during the passage of the coupling head of the second position deployed towards the first retracted position;

- The hooking and unhitching between, on the one hand, the hook of the first coupling means of the coupling head, and on the other hand the corresponding hook of the lower working cylinder are caused by the movements of the carriage, following a direction perpendicular to the support rails; According to one embodiment, the second coupling means comprise at least one folding element suitable for cooperating with the chock of the lower support cylinder, which

in said deployed position of said folding element, it is possible to engage abutment with the motor-drive side chock of the lower support roll to exert a pull, allowing insertion of the lower support roll and the support equipment during said inserting step,

- In the folded position of said collapsible element, allows, successively to said third extraction step to uncouple the coupling head of said lower bearing cylinder extracted from the holding cage, during the return movement of the coupling head from the second position deployed to the first retracted position.

The invention also relates to a rolling plant having:

a mill comprising:

a holding cage,

each cylinder having two rotatably mounted ends, each on a bearing carried by a chock,

guiding means between the chocks of the rolls and the holding cage along the clamping plane,

means for applying a clamping force between the chocks of the support rolls, comprising hydraulic jacks,

a system for clamping the chocks of the rolls, ensuring the locking of the chocks with respect to the holding cage, along the axis of the cylinder, while allowing the sliding of the chocks along the guide means, according to the clamping plane,

means for motorizing the support rolls, on one side of the roll stand,

a system for extracting the work rolls and support rollers located on the motorization side of said rolling mill, comprising:

a coupling head integral with said actuator, located in the open position of the holding cage, at an intermediate height level between the lower working roll and the lower bearing roll, movable in a direction parallel to the rolls; from a first retracted position for which the coupling head is located motor side, to a second extended position for which the coupling head having passed through the holding cage is located operator side, said coupling head comprising:

first coupling means configured to drive the chock or the end of the lower working roll, next to the drive means of the rolling mill,

second coupling means configured to drive the chock of the lower support roll, on the motorization side of the rolling mill, exhibiting a retracted state in which they do not lead to the chock of the lower support roll and an expanded state in which they push the chock of said lower support cylinder,

and in which the chocks of the upper and lower work rolls have connecting means, on the operator side, opposite to the drive means, providing a mechanical connection between these chocks on the operator side, and wherein the first coupling means and the second coupling means of said extraction system are configured to allow:

- The successive extractions of the working rolls, then support cylinders out of the holding cage, - the successive insertions of the support cylinders, then the working rolls in the holding cage.

According to the invention, the second coupling means comprise at least one movable element, articulated to the frame of the coupling head, suitable for cooperating with the thrust with the chock of the lower support cylinder, which:

- In the retracted state of the second coupling means, said at least one movable element is reassembled and locked in a retracted position where said movable element does not engage with the chock, the lower support cylinder, motor side of the rolling mill,

in the deployed state, the second coupling means is in a deployed position in which the said moving element projects downwards under the action of gravity.

Advantageously, said movable member is a manually actuated member to move from the retracted position to the deployed position of said movable member, or conversely, said movable member being configured in said extended position to engage with a projecting portion on the upper face of the chock of the lower support cylinder on the drive side, present in the support cage, and in such a way that:

- Said passage of the coupling head of the second deployed position to the first retracted position causes the engagement of the projecting portion against the movable member, which pivots about its articulation under the action of the protruding part, to escape said protruding part, before returning, under the effect of gravity, in the position where said movable element projects downwards, on the other side of the projecting part;

said moving element, then in position on the other side of the projecting portion, abuts against said projecting part under the actuator pushing action and so as to allow the output of said lower support cylinder. _{1 r}

16

According to one embodiment:

- said rolling installation comprising a support carriage having supporting rails suitable for supporting and guiding the chocks of the lower and upper working rolls, which, in a relative position of the carriage with respect to the rolling mill, extend the support rails of the rolling mill and such that the lower and upper work rolls are loaded on the carriage during the thrust action of the actuator on the work rolls.

According to optional features of the installation, taken alone or in combination:

the first coupling means comprise a hook rigidly secured to the coupling head intended to engage with a corresponding hook secured to one of the ends of the lower work rollers and suitable for exerting a thrust force on the lower work roll during the thrust action of the coupling head from the first retracted position to the second deployed position, and to exert a traction force on the lower working cylinder during the passage of the coupling head of the second position deployed to the first retracted position;

the hooking and unhitching between, on the one hand, the hook of the first coupling means of the coupling head, on the one hand, and the corresponding hook of the lower working cylinder are caused by the movements of the carriage, in a direction perpendicular to the support rails.

According to one embodiment, the second coupling means comprise at least one folding element suitable for cooperating with traction with a chock of the lower support cylinder on the motorization side, which in said extended position of said folding element, it is possible to engage abutment with the motor-drive side chock of the lower support cylinder to exert traction, allowing insertion of the lower bearing cylinder in the roll stand,

- In the folded position of said folding element, allows to decouple the coupling head of said lower bearing cylinder extracted from the holding cage, during the return movement of the coupling head of the second deployed position to the first retracted position.

According to an advantageous embodiment said folding element is a manually actuated member to move from the deployed position to the folded position of said folding member, or vice versa.

According to one embodiment, the chocks on the operator side of the work rolls having sliding plates, parallel and distributed on either side of the axis of the cylinder, intended to cooperate with sliding plates integral with two uprights operator side of the rolling mill, the connecting means comprise at least one blade whose proximal end is integral with one of the lower or upper chocks, received in a lateral groove, formed in the body of the chock, on the back of a plate sliding, and whose distal end enters a groove of the other chock, at least in an extended position of said blade, in said open position of the holding cage.

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

FIG. 1 is an overall perspective view illustrating the rolling mill of the Quarto type, including the holding cage in which the support and working cylinders are present, the motorization of the bearing rolls of the rolling mill, as well as the extraction system with a single actuator, of the motorized pinion / rack type, located on the motorization side of the rolling mill, the perspective view still illustrating, on the operator side of the holding cage (opposite to that of the motorization), the carriage supporting the cylinders working, U-shaped support equipment (removable), insertable into the support cage intended to jointly release the two support cylinders, and still handling devices for lifting the support cylinders and work, or said support equipment,

- Figure 2 is a sectional view along a plane passing through the clamping plane of the rolling mill, illustrating more particularly the extraction system, in said first retracted position of the coupling head,

FIG. 3 is a detailed view of FIG. 3 illustrating more particularly the hook of the first coupling means of the coupling head, in engagement with a corresponding hook integral with the end (motor side) of the lower working cylinder. in the first retracted position of the coupling head,

FIG. 4 is a sectional view of the rolling mill, in a vertical plane perpendicular to the rolls,

FIG. 5 is a view of the rolling stand of the rolling mill,

FIGS. 6 and 7 are views of the working and bearing cylinders, respectively in the closed position and the opening of the holding cage,

- Figures 8 and 9 are partial views of the rolling facility, operator side, illustrating the support carriage of the working rolls, respectively in a retracted position of the extraction zone, and in a carriage position for receiving working cylinders during their extraction, - Figure 10 is a detailed view of the chocks (operator side) of the working rolls, and more particularly the organs for the creation of a mechanical connection ensuring the joint output of the two cylinders of when the actuator of the extraction system only exerts a thrust (motor side) on the lower working cylinder, - Figure 11 is a view, motor side of the rolling mill, in the first retracted position of the coupling head, said first coupling means then engaged with the end of the lower support cylinder, said second coupling means in the retracted state in which they do not lead to the thrust of the lower support cylinder,

FIG. 12 is a successive view of FIG. 11, illustrating the first extraction step in which the actuator drives the coupling head to the thrust, then in engagement with the lower working cylinder, thus causing the extraction of the lower working cylinder and, together, the upper working cylinder by means of the mechanical connection illustrated in FIG. 10, the upper and lower work rolls thus being loaded onto the support rails of the support carriage, the support rolls, 5 is a consecutive view of FIG. 12, the upper and lower working cylinders then extracted from the holding cage and completely supported by the carriage when said coupling head is in its position. second position deployed,

FIG. 14 is a subsequent view of FIG. 13, for which the support carriage is moved laterally, releasing the extraction zone, operator side of the holding cage,

- Figures 15 and 16 are respectively two views of the coupling head then located, operator side, in said second deployed position, said movable member hinged to the frame of the coupling head along a horizontal pivot axis, being manually tilted from a retracted position illustrated in Figure 15 for which said movable member is not likely to interact with the chock of the lower support cylinder, to an extended position, illustrated in Figure 16, allowing engage with the chock (motor side) of the lower support cylinder, when returning the coupling head to the drive side,

FIGS. 17 and 18 are two detailed views illustrating the passage of the system for clamping the chocks of the support rollers from a chock locking position to an unlocked position, releasing the axial displacement of the support rolls,

FIG. 19 is a view illustrating the step of returning the coupling head towards the first retracted position, - Figures 20 to 23 are respectively successive views of the detail of the return of the coupling head from the second extended position to the first retracted position, the figures respectively illustrating the engagement of a projecting portion on the upper face of the 'chocks against the movable element, freely articulated, which, when the return of the coupling head, pivots around its articulation under the action of the protruding part to escape said projecting part, before returning, under the effect gravity, in the position where said movable element projects downwards, on the other side of the projecting portion of the chock, into said first position of the coupling head;

FIG. 24 is a subsequent view of FIG. 23, illustrating the second extraction step for which the lower support cylinder is extracted by the thrust action of the coupling head, thanks to the movable member of FIGS. second coupling means which abuts against the protruding portion of the empoise motor side,

FIG. 25 is a consecutive view of FIG. 24, the support cylinder totally extracted in said second deployed position of the coupling head; FIG. 26 is a subsequent view of FIG. 25 illustrating the positioning of a support element, insertable in the holding cage, whose lower part rests on the chocks of the lower support roll, and whose upper part is provided to support the chocks of the upper support roll,

- Figure 27 is a detailed view of the coupling head, illustrating more particularly two folding elements in their deployed position, for engaging abutting with the chock (motor side) of the lower support cylinder to exercise a traction, and in order to allow insertion of the lower support roll into the roll stand,

FIG. 28 is a view illustrating the insertion step during which the lower support cylinder and said support equipment are inserted together in the holding cage, by the traction action caused by the return of the head coupling to the motorization side the metal strip then received in an intermediate clearance of the support equipment, FIGS. 29 and 30 are consecutive views illustrating the depositing step during which the upper support roll is deposited on the upper part of the support equipment by a descent action of said upper support roll,

FIG. 31 is a view illustrating the third extraction step during which the coupling head extracts jointly, during the thrust action of the actuator, the lower support cylinder, the support equipment and the upper support cylinder,

- Figure 32 is a detail view of the coupling head, more particularly illustrating the folding elements in their folded position, following a manual action on the operator side, for decoupling the coupling head of said lower bearing cylinder during the return movement of the coupling head towards the motorisation side.

- Figure 33 is a successive view of Figure 32 illustrating the decoupling step of the coupling head of said lower bearing cylinder.

Also the invention relates to a rolling mill 1, in particular of the Quarto type, for metal strip comprising a holding cage 2, comprising two pairs of uprights, at the two ends of the cage between which are provided a set of superimposed rolls, with substantially axes. parallel, comprising two working rolls 3,4, lower and upper, defining the passage gap, and two bearing cylinders 5,6 respectively lower and upper, intended to respectively bear on the working rolls of the opposite side to that of the passing gap. Each working or bearing cylinder has two ends, typically called journals, rotatably mounted, each on a bearing carried by a chock 30, 40, 50, 60.

The rolling mill further comprises guiding means between the chocks 30, 40, 50, 60 of the rolls and the holding cage 2, according to the clamping plane. These guide means may comprise sliding surfaces between the chocks and the frame (in particular the uprights) of the holding cage 2.

For example : _

22

each chock 30 of the upper working cylinder 3 has two sliding plates 31, parallel and opposite, distributed on either side of the axis of rotation of the working roll 3, cooperating with two sliding plates 27, respectively rigidly secured to the uprights of the same pair at one end of the holding cage,

each chock 40 of the lower work roll 4 has two sliding plates 41, parallel and opposite, distributed on either side of the axis of rotation of the working roll 4, cooperating with the sliding plates 27, respectively rigidly secured to the amounts of the same pair at one end of the holding cage.

For example, the two sliding plates 27 are respectively secured on the internal walls of two blocks of the camber cylinders Vc3, Vc4, themselves respectively secured by their outer wall to the two inner walls of the amounts of the same pair of studs. the cage. Likewise:

each chock 50 of the upper support cylinder 5 may have two sliding plates 51, parallel and opposite, distributed on either side of the axis of rotation of the support cylinder 5, cooperating with sliding plates 25 rigidly secured to the uprights of the same pair at one end of the holding cage, and

each chock 60 of the lower support roll 6 may have two parallel and opposite sliding plates 61, distributed on either side of the axis of rotation of the support roll 6, cooperating with sliding plates 26 rigidly secured to the uprights of the same pair at one end of the holding cage.

The rolling mill also comprises means for applying a clamping force between the chocks of the support rolls, typically comprising hydraulic cylinders Vs. These hydraulic cylinders Vs, which can be two in number, can be arranged in the lower part of the support cage. maintaining and respectively support the two chocks 60 of the lower support cylinder 6. According to an embodiment not shown, these cylinders Vs hydraulic can still be provided in the upper part of the support cage 2 and bear respectively on the chocks of the upper support cylinder.

The rolling mill further comprises a system for clamping the chocks 30, 40 of the work rolls 3 and 4, and a clamping system 9 of the chocks 50, 60 of the support rollers 5, 6.

The clamping system of the work rolls illustrated in the examples is that which was the subject of the applicant of the filing of the French patent application FR 1652265 of March 17, 2016 which allows to lock the chocks of work rolls, or otherwise to release the axial displacement of the working cylinders by the actions of opening and closing of the holding cage. The description of this clamping system for work rolls is not explicitly mentioned in the present application. The skilled person can, however, refer to this document for its execution. In the context of the present application, other systems for clamping the work rolls are possible and in particular that with dedicated cylinders described as state of the art in the application FR 1652265.

The clamping system 9 of the chocks of the support cylinders to pass from a retracted state, allowing the withdrawal along their axis of the support rolls out of the holding cage to a blocking state ensuring the locking of the chocks with respect to the cage, along the axis of the cylinder, while allowing the sliding of the chocks along the guide means, according to the clamping plane.

This clamping system 9 may comprise vertical grooves of the chocks 50, 60 of the upper support cylinder 5 and the lower support cylinder 6, as well as locking members 90, mounted to slide horizontally. Each locking member can move from a position where it enters the vertical groove of the chocks 50 or 60, blocking the axial displacement of the support cylinder, to a retracted position where the axial displacement is released. Given the maintenance frequency of the support cylinders, the clamping system can be manual, the passage from the retracted position to the locking position is manual being obtained by actuating a handle 91. The rolling mill further comprises motorization means 10 of the support rollers, on one side of the roll stand, said engine side in the remainder of the invention.

In a conventional manner for those skilled in the art, an electric motor M drives the lower and upper bearing cylinders, through a transmission connecting the output of the engine to the ends of the support cylinders motor side.

The invention is more particularly concerned with the extraction system of the work rolls and the support rolls, and which is situated on the motor side of said rolling mill.

This extraction system makes it possible, as will be developed later, to extract the used cylinders from the roll stand, in particular with a view to their rectification, but also to insert rolled (or new) rolls in the support cage.

For this purpose the extraction system comprises:

an actuator 70 configured to push the rolls out of the holding cage 2 of the rolling mill during the extraction of the rolls, or on the contrary pulling the rolls into the holding cage 2 during the insertion of the rolls,

a coupling head 8 integral with said actuator 70, located in the open position of the holding cage 2, at an intermediate height level between the lower working roll 4 and the lower bearing roll 6, movable according to a direction parallel to the cylinders 3,4,5,6.

The actuator may comprise a rack and pinion torque 71 motorized pinion 72, the frame of the coupling head 8 being rigidly secured to the distal end of the rack 71. The rotation of the pinion 72 in a first direction allows the translation according to its axis of the rack and the coupling head 8. The coupling head 8 is movable from a first retracted position PI for which the coupling head is located motor side, to a second deployed position P2 for which the headstock 8 having passed through the holding cage 2 is located operator side, accessible for them. Moreover, said coupling head 8 comprises

first coupling means configured to drive the chock 40 or the end of the lower working roll 4, on the motorization side of the rolling mill,

second coupling means configured to drive the chock 60 of the lower support roll 6, on the motorization side of the rolling mill: the second coupling means having a retracted state in which they do not lead the chock of the support roll; lower 6 to an expanded state in which they push the chock 60 of said lower support cylinder 6.

Notably, the chocks 30, 40 of the upper and lower work rolls have connection means 11, on the operator side, opposite to the drive means, providing a mechanical connection 12 between these chocks on the operator side.

This mechanical connection 12 makes it possible to ensure the joint exit of the two working rolls 3, 4 when the actuator 70 of the extraction system exerts only a thrust (motor side) on the lower working roll, and as will be explained thereafter.

For example, and as shown in FIG. 10, the chocks on the operator side of the work rolls having said sliding plates 31, 41 (not shown), parallel and distributed on either side of the axis of the roll, intended to cooperate with the sliding plates 27 secured to two uprights on the operator side of the rolling mill, the connecting means 11 may comprise at least one blade 15 (or two blades 15) whose proximal end is integral with the one marked lower chocks or upper, received in a lateral groove, formed in the body of the chock, on the back of a sliding plate 31 or 41, and whose distal end 16 enters a groove of the other chock, on the back of the sliding plate, at least in an extended position of said blade, in said open position of the holding cage. Note that the (or each) blade 15 is substantially parallel to the sliding plates 31 or 41 the distal end 16 of the blade may have a rounded contour so as to allow a slight pivoting of the distal end in the groove to be in particular observed during bending action on the work rolls. The blade 15 may also be provided retractable in a position retracted into the chock 30 (position not shown), the chock 30 having means for locking said blade 15 in the deployed position. These means may comprise a spring ball system. An oblong opening 17 of the blade intended to be traversed by a stud 18, integral with the chock may also be provided to prohibit the disassembly of the blade

Advantageously, the first coupling means and the second coupling means of said extraction system are configured so as to allow:

- The successive extractions of the working cylinders and support cylinders out of the holding cage. - The successive insertions of the support cylinders and the working cylinders in the holding cage.

In other words, the invention advantageously allows:

the extraction of all the rolls of the rolling mill (i.e working rolls, then support rolls) by means of a single actuator, and contrary to the prior art known to the Applicant,

the insertion of all the rolls of the rolling mill (i.e support rolls, then working rolls) by means of a single actuator, and contrary to the state of the art known to the Applicant.

As will be understandable from the following description, the extraction system possibly makes it possible to extract only the work rolls, and then to insert new working rolls (new or rectified) into said holding cage (the rolls of remaining support in the support cage). The method of changing the rolls used in such a rolling installation is described below, and more particularly the various steps used to extract all of the work rolls and the support rollers by means of the rolling mill system. extraction with a single actuator. These different steps are illustrated in detail in Figures 6 to 33.

Those skilled in the art understand that the steps of the method for inserting the support rolls, and then the working rolls are essentially the same, but performed in the reverse order of the steps for extracting the rolls.

Also, the working rolls 3,4 and the support rollers 5,6 are extracted, after opening of the holding cage of said rolling mill during which the lower work roll 4 and lower support roll 6 are separated from the upper working cylinder 4 and the upper support cylinder 5, while the metal strip B is present along the scroll plane of said rolling mill.

This step of opening the roll stand is illustrated in FIGS. 6 and 7, caused by the retraction of the hydraulic cylinders Vs. If necessary, and according to one embodiment, this opening automatically causes the declamation of the chocks 30, 40 of the working rolls 3, 4.

Moreover, the working rolls 3,4 and the support rollers 5,6 are extracted by the following successive steps: a first extraction step E1 (see FIGS. 11 to 13; ) during which are extracted the upper working cylinder 3 and the lower working cylinder 4, by a pushing action of said actuator 70 on the chock 40 of the lower working cylinder 4, motor side, the coupling head 8 passing from the first retracted position PI to the second extended position P2, said upper working cylinder 3 being driven together with the lower working cylinder 4 by the mechanical link created 12, operator side, between the chocks 30, 40 of the working cylinders lower and upper, said second coupling means of the coupling head 8 being in said retracted state where they do not cause the chocks of the support cylinders during this thrust action, - A return step E2 (see Figures 19 to 24) during which the coupling head 8 is returned from the second extended position P2 towards the motor side to the first retracted position PI,

a second extraction step E3 (see FIGS. 24 and 25) during which the lower support cylinder 6 is extracted from the holding cage 2 by a pushing action of said actuator on the chock 60 of the cylinder of lower support 6 motor side, the coupling head 8 passing from the first retracted position PI to the deployed position P2, said second coupling means being in said expanded state for driving the thrust of the chock 60 of said cylinder d lower support 6, - a positioning step E4 (see FIGS. 26 and 27) during which a support equipment 13 is positioned on the lower support cylinder 6, the lower part of which bears against the chocks 60 of the cylinder lower support 6, and whose upper part is intended to serve as a support for the chocks 50 of the upper support cylinder), said support equipment 13 being insertable into the holding cage 2, - an insertion step E5 ( voi r Figure 28) during which the lower support cylinder 6 and said support equipment 13 are inserted into the holding cage 2, by the traction action caused by the return of the coupling head 8 towards the side motorization from the deployed position P2 to the retracted position PI, said support equipment 13 having a clearance 14 traversed by the metal strip B when inserted into the holding cage 2,

a deposition step E6 (see FIGS. 29 and 30) during which the upper support roll 5 is deposited on the upper part of the support equipment 13, by a descent action of said upper support roll 5,

a third extraction step E7 (see FIG. 31) during which is extracted the assembly comprising the lower support cylinder 6, the support equipment 13, and the said upper support cylinder 5 by a pushing action said actuator 70 on the chock 60 of the lower support cylinder 6, motor side.

The holding cage 2 of the rolling mill typically comprises support rails R3, R4 on which the chocks 30, 40 of the upper work rolls and lower 3.4, in the open position of the holding cage 2, said support rails R3, R4 guiding the working rolls 3,4 and their chock 30,40 during the extraction of the work rolls out of said holding cage or during the insertion of the working rolls in the holding cage. The support cage also comprises support rails R6 on which the chocks 60 of said lower support cylinder 6 rest in the open position of the holding cage 2, the chocks 60 having rollers 63 intended to roll along the rails. R6, other rails extending the rails R6 at the extraction area operator side. The rolling plant may comprise a support carriage comprising support rails R3 ', R4' suitable for supporting and guiding the chocks 30, 40 of the lower and upper work rolls 3,4 which, in a relative position of trolley relative to the rolling mill, extend the support rails R3, R4 of the rolling mill and so that the lower and upper work rolls are loaded together on the carriage 20 during the actuator pushing action on the work rolls 3,4, or on the contrary unloaded from the carriage to be inserted into the holding cage during the insertion of cylinders.

This support carriage 20 is movable along rails perpendicular to the support rails, to allow the carriage to retract laterally to a position outside the extraction zone, and as illustrated in FIG. 8.

A handling frame M _T allows to evacuate through the work rolls 3,4 from above, thanks to a crane of the workshop.

This carriage 20 is held in this retracted position outside the extraction zone, in particular during the steps for which the support cylinders are extracted or inserted.

As illustrated in the figures, the carriage may have, in parallel, four pairs of support rails, and so as to be able to support two pairs of upper work rolls, and lower, side by side. When only the work rolls 3,4 are to be changed, it is then possible to jointly extract a pair of upper and lower work rolls on the support carriage 20 and immediately load another pair of work rolls (new or rectified). ) previously positioned on the support carriage, just after a small lateral displacement of the carriage so as to align the support rails R3 'and R'4 of these new cylinders with those R3 and R4 of the holding cage 2.

The first coupling means may essentially comprise a hook 81 rigidly secured to the coupling head 8 intended to engage with a corresponding hook 42 secured to the motor-side end of the lower work roll 4, and suitable for:

- Exert a thrust force on the lower work roll 4 during the pushing action of the coupling head 8 of the first retracted position PI to the second deployed position P2,

- Trying on the lower work roll 4 during the passage of the coupling head 8 of the second deployed position P2 to the first retracted position Pl.

This hook 81 is initially engaged with the corresponding hook 42 at the end of the lower work roll, in said first retracted position PI of the coupling head, and as illustrated in FIGS. 3 or 11. Advantageously, the two hooks 81 and 82 mutually engaging are configured so that the hooking and unhitching between, on the one hand, the hook 81 of the first coupling means of the coupling head 8, and on the other hand, the corresponding hook 42 of the cylinder 4, are caused by the movements of the carriage 20, in a direction perpendicular to the support rails R3 ', R4'. The coupling (or decoupling) of the coupling head 8 with the lower working cylinder 4 is therefore automatic thanks to the motorized movement of the support carriage, and without the need for a dedicated actuator for this action.

As illustrated in FIGS. 12 and 13, the support rails R3 'and R4' of the support carriage are aligned with the support rails R3 and R4 during the first extraction step E1. At the end of the extraction step, the carriage 20 is retracted into a position outside the extraction zone, operator side, and as illustrated in FIG. 14, and while the coupling head is in the second deployed position P2, accessible to the operator. This access to the coupling head 8 advantageously allows, according to the invention, an operator to pass the second coupling means of the retracted state in which they do not lead the chock of the lower bearing cylinder to the deployed state in which they drive to push the chock of said lower support cylinder by a manual action of the operator on said second coupling means. This manual action is successive to said first extraction step, performed while the coupling head is in said second extended position accessible operator side of said rolling mill, and prior to said step of returning the coupling head.

For this purpose, the second coupling means may comprise at least one movable element 82, articulated to the frame of the coupling head, suitable for cooperating with the thrust with the chock 60 of the lower support cylinder 6.

in the retracted state of the second coupling means, said at least one movable element 82 is raised and locked in a retracted position P3, illustrated by way of example in FIG. 15, in which said movable element 82 does not engage with the chock 60, of the lower support cylinder 6, on the motorization side of the rolling mill, in the deployed state of the second coupling means, the at least one movable element 82 is in an extended position P4, illustrated for information in FIG. wherein said movable member 82 projects downward under the action of gravity.

The passage from the retracted position P3 to the deployed position is thus possible by a manual action of the operator, when the coupling head 8 is accessible operator side. In the retracted position, the movable member 82 can be locked in position by any suitable means, and for example by means of a fork 85, articulated to the frame, which in a position makes it possible to hold the movable member 82 in position reassembly by engagement with a tab 84 rigidly secured to the movable member. The unlocking is obtained by moving the fork 85 around its pivot, this displacement causing the release of the movable member which pivots upside down, for example a half-turn under the effect of gravity.

This movable element 82 is configured in said extended position P4 to engage with a projecting portion 62 on the upper face the chock 60 of the lower support cylinder 6 motor side, present in the holding cage.

As illustrated in FIGS. 20 to 23, said passage of the coupling head 8 from the second extended position P2 to the first retracted position PI causes the protrusion 62 to engage against the movable element 82, which pivots around its articulation under the action of the protruding portion 62 (see Figures 20 to 22), to escape said projecting portion 6 before returning, under the effect of gravity, in position (see Figure 23) where said movable member 82 projects to the bottom, on the other side of the projection 62. In other words, when returning the coupling head, said movable member 82 is configured to escape a projecting portion 62 on the upper face of the chock 60 of the cylinder lower support 6, thanks to the possibility of rotation of said at least one movable element (in the clockwise direction in Figures 21 and 22).

As illustrated in FIG. 24, said movable element 82, then in position on the other side of the projecting portion 62, abuts against said projecting portion 62 under the thrust action of the actuator 70 and so as to allow the output of said lower support cylinder 6 during the second extraction step E3. During the extraction E3, it is noted that the possibility of rotation of said movable member 82 (counterclockwise) is blocked by a stop 86, which allows said movable member 82 to transmit to the chock 60 the thrust force necessary for the extraction of the lower support cylinder 6.

Prior to the extraction of the support cylinders, it is of course necessary to release the axial displacement of the cylinders by unlocking the clamping system 9 of the chocks of the support rollers.

The second coupling means may comprise, as illustrated in the figures, two movable elements 82 substantially parallel, and rigidly secured to the same rotation shaft to the frame of the head. The rotation shaft is substantially horizontal and perpendicular to the axis of the lower support cylinder. The two moving elements are intended to cooperate respectively with two projecting parts on the upper face of the chock 60 of the lower support cylinder 6.

At the end of the second extraction step E3, the lower support roll 6 is extracted from the holding cage 2, and as shown for information in FIG. 25. The next step is said positioning step E4 at during which is positioned by means of a handling device (ie a crane) a support equipment 13 on the lower support cylinder 6.

The lower part of this equipment is supported on the chocks 60 of the lower support cylinder 6. The upper part is intended to serve as a support for the chocks 50 of the upper support cylinder 5. This support equipment 13 is notable in that it can be inserted (once the working rolls removed) in the holding cage 2, together with the lower support roll.

For this purpose, the second coupling means comprise at least one folding element 83 suitable for cooperating with traction (only) with the chock 60 of the lower support cylinder 6 on the motor side, which

in an extended position P5 of said folding element 83, it is possible to engage in abutment with the chock 60 on the motor side of the lower support cylinder 6 to exert traction, allowing the insertion of the lower support cylinder 6 into the cage of the rolling mill, in particular during step E5. - In a folded position P6 of said folding element 83, allows to decouple the coupling head of said lower support cylinder 6, extracted from the holding cage, during the return movement of the coupling head of the second position deployed P2 to the first retracted position Pl.

Notably, said at least one folding movable element 83 may initially be in the deployed position P5 in that it does not allow to exert thrust force on the cylinder.

The folding elements 83 may be two in number and engage in abutment with the two projecting parts 62. The passage from the deployed position P5 to the folded position P6 can be obtained manually, for example by rotating according to a limited angle for example of a quarter turn of said element 83. For this purpose, the or each element may have a fingerprint intended for a tool such as a key.

The two collapsible elements in their deployed position P5 make it possible, during the insertion step E5, to jointly engage the lower support cylinder 6 in the holding cage, as well as the said support equipment 13 supported by the chocks 60, and as illustrated in FIG. 28. It will be noted that the metal strip present in the rolling plane of the rolling mill is housed in an intermediate clearance 14 of said support equipment 13.

This then allows the removal of the upper support cylinder 5 on said support equipment, by the descent of the upper support cylinder 5, this action can be performed by deployment of hydraulic cylinder V _R and until the chocks 50 of the upper support cylinder 5 rest on said support equipment 13, these V _R cylinders being typically used otherwise for the adjustment of the pass line.

Then, it follows the third extraction step E7 during which by a new thrust action of said actuator 70 on the chock 60 motor side of the lower support cylinder 6 is extracted the assembly comprising the cylinder of lower support 6, the support equipment 13, and said upper support cylinder 5, said coupling head then being in its second deployed position P2.

The coupling head 8 is cut by a manual action on the folding elements 83 which have passed into their folded position P6, then by the return of the coupling head towards the first retracted position P1.

The upper support cylinder 5, said support equipment 13, then the lower support cylinder 6 can then be discharged from the extraction zone, from above, by a handling frame M _A , illustrated in FIG. raised by a traveling crane. Naturally other embodiments could have been envisaged by the skilled person without departing from the scope of the invention as defined by the claims below. NOMENCLATURE.

1. Rolling plant,

2. Holding cage,

3.4. Work rolls, respectively upper and lower,

5.6. Support cylinders, respectively upper and lower,

30.40. Cylinders of work rolls, respectively upper and lower, 42. Hook at the motor end of the lower work roll,

50, 60. Stacks of the support cylinders, respectively upper and lower, 31, 41, 51, 61. Chuck slip plates,

62. Projecting parts on the upper face of the chock 60 of the support cylinder (motor side),

63. Rollers (chocks 60)

25, 26, 27. Sliding plates (frame),

7. Extraction system,

70. Actuator (extraction system)

71, 72. Rack and motorized gear (extraction system actuator),

8. Coupling head (extraction system),

81. First coupling means (rigidly integral hook of the body of the coupling head) suitable for exerting (only) a thrust force and a traction force on the lower working cylinder 4

82.83. Second coupling means, including the manually retractable movable member 82 suitable for exerting a thrust force on the chock 60 of the lower bearing roll, and the manually folding elements 83 suitable for exerting (only) a tensile force on this chock.

84. Paw,

85. Fork,

86. Stop, 9. Clamming system of support cylinders,

90. Locking member (clamming system 9),

91. Handle (clamming system)

10. Means of motorization (support cylinders),

11. Means of connection, operator side, between the chocks 30,40 of the working rolls,

12. Mechanical link

13. Support equipment,

14. Release of the support equipment intended to be traversed by the metal strip,

15. Blades,

16. Distal Ends (Blades)

17. Oblong opening

18. Plot

20. Support trolley (working cylinders)

B. Metal strip,

El. First Extraction Step (Lower and Upper Working Cylinders 34), E2. Return step (coupling head),

E3. Second extraction step (lower support cylinder 6),

E4. Positioning step of the support equipment 13 on the chocks of the lower support cylinder then extracted from the holding cage,

E5. Joint insertion step of the lower support roll 6 and the support equipment 13 in the holding cage,

E6. Step of removing the upper support cylinder 5 on the support equipment 13,

E7. Third extraction step of the assembly comprising the lower support cylinder 6, said support equipment 13 and the upper support cylinder 5

PI, P2. Positions respectively retracted (motor side) and deployed (operator side) of the coupling head, P3, P4. Positions respectively retracted and deployed of said at least one movable element 82, said extended position being suitable for exerting a pushing action on the chock of said support cylinder, motor side,

R3, R4, R6. Supporting rails of the holding cage suitable for guiding respectively the upper work rolls, the lower work roll, and the lower support roll.

R3 ', R4'. Support rails of the support carriage 20,

Vc3, Vc4. Bending cylinders

V _R. Jack of adjustment of the pass line

Vs. Hydraulic cylinders (means for applying a clamping force between the chocks of the support rolls),

M _A. Handling chassis (support cylinders),

Μχ. Handling chassis (working cylinders).

Claims

1. A method of changing the rolls of a metal strip rolling mill, implemented in an installation (1) having:

a mill comprising:

a cage (2) for holding,

a set of superimposed cylinders with substantially parallel axes comprising two lower and upper working rolls (3,4) defining the passage gap, and two lower and upper bearing rolls (5,6) intended to take respectively support on the working cylinders on the opposite side to that of the passage gap,

each cylinder having two rotatably mounted ends, each on a bearing carried by a chock (30, 40, 50, 60)

means for applying a clamping force between the chocks of the support cylinders, comprising hydraulic cylinders (Vs),

a clamping system (9) for the chocks of the rolls, ensuring the locking of the chocks with respect to the holding cage, along the axis of the roll, while allowing the chocks to slide along the guiding means, according to the plan Clamping,

- Motorization means (10) of the support rollers, one side of the roll stand, said engine side,

an actuator (70) configured to push the rolls out of the roll stand (2) during the extraction of the rolls, or on the contrary to pull the rolls into the holding cage (2) during the insertion of the rolls; cylinders,

- a coupling head (8) integral with said actuator (70), located in the open position of the holding cage (2), at an intermediate height level between the lower working cylinder (4) and the cylinder of lower support (6), movable in a direction parallel to the cylinders (3,4,5,6), since a first retracted position (PI) for which the coupling head is located motor side, to a second deployed position (P2) for which the coupling head (8) having passed through the holding cage (2) is located operator side, said coupling head (8) comprising

first coupling means configured to drive the chock

(40) or the end of the lower working roll (4), motorization side of the rolling mill,

second coupling means configured to drive the chock of the lower support roll (6), on the motorization side of the rolling mill, having a retracted state in which they do not cause the chock of the lower support roll (6). and an expanded state in which they push the chock (60) of said lower support cylinder (6),

and wherein the chocks (30, 40) of the upper and lower work rollers have connecting means (11), on the operator side opposite the drive means, providing a mechanical connection (12) between these chocks on the operator side, and in which the work rolls (3, 4) and the support rollers (5, 6) are extracted after opening the holding cage of said rolling mill during which the lower work roll (4) ) and lower bearing cylinder (6) are spaced apart from the upper work roll (3) and the upper support roll (5), while the metal band (B) is present along the rolling plane of said rolling mill by the implementation of the following successive steps:

a first extraction step (E1) during which the upper working cylinder (3) and the lower working cylinder (4) are extracted by a pushing action of said actuator (70) on the chock (40); ) of the lower working cylinder (4), motor side, the coupling head (8) passing from the first retracted position (PI) to the second extended position (P2), said upper working cylinder (3) being jointly driven with the lower working cylinder (4) by the mechanical connection created (12), operator side, between the chocks (30,40) of the lower and upper working rolls, said second coupling means (81, 82) of the head coupling (8) being in said retracted state where they do not cause the chocks of the support cylinders during this thrust action, - a return step (E2) during which the coupling head (8) is returned from the second extended position (P2) towards the motor side to the first retracted position (PI),

a second extraction step (E3) during which the lower support cylinder (6) is extracted from the holding cage (2) by a pushing action of said actuator on the chock (60) of the cylinder lower support (6) on the motor side, the coupling head (8) passing from the first retracted position (PI) to the second deployed position (P2), said second coupling means being in said deployed state for driving the thrust of the chock (60) of said lower support cylinder (6) - a positioning step (E4) during which a support equipment (13) is positioned on the lower support cylinder (6), of which the lower part rests on the chocks (60) of the lower support cylinder (6), and whose upper part is intended to serve as a support for the chocks (50) of the upper support cylinder (5), said support equipment (13) being insertable into the holding cage (2),

- an insertion step (E5) during which the lower support cylinder (6) and said support equipment (13) are inserted into the holding cage (2), by the traction action caused by the return from the coupling head (8) towards the drive side from the second extended position (P2) to the first retracted position (PI), said support equipment (13) having a clearance (14) traversed by the metal strip (B). ) when inserted into the holding cage (2)

- a removal step (E6) during which the upper support cylinder (5) is deposited on the upper part of the support equipment (13), by a descent action of said upper support cylinder (6) ,

a third extraction step (E7) in which is extracted the assembly comprising the lower support cylinder (6), the support equipment (13), and the said upper support cylinder (5) by a pushing action of said actuator (70) on the chock (60) of the lower support cylinder (6), motor side

and in which the second coupling means of the retracted state are passed in which they do not cause the chock of the lower support cylinder (6) to the deployed state in which they drive the choke ( 60) of said lower support cylinder (6) by a manual action on said second coupling means, successively to said first extraction step (El), the coupling head (8) being in said second deployed position (P2), accessible on the operator side of said rolling mill, and before said return step (E2).

The method of claim 1, wherein:

- The holding cage (2) of the rolling mill comprises support rails (R3, R4) on which rest the chocks (30, 40) of the upper and lower work rolls (3,4), in the open position of the holding cage (2), said support rails (R3, R4) guiding the working rolls (3, 4) and their chock (30, 40) during the extraction of the rolls in said holding cage,

- said rolling installation comprising a carriage (20) comprising supporting rails (R3 \ R4 ') suitable for supporting and guiding the chocks (30, 40) of the lower and upper work rolls (3), which, in a relative position of the carriage relative to the rolling mill extend the support rails (R3, R4) of the rolling mill, and in such a way that the lower and upper work rolls are loaded on the carriage (20) when the head of hitch reaches said second deployed position (P2) during the first extraction step (E1).

3. Method according to claim 1 or 2, wherein the first coupling means (81) comprise a hook rigidly secured to the coupling head (8) intended to engage with a corresponding hook (42) integral with the end end. motorization of the lower work roll (4), and suitable for:

- exerting a thrust force on the lower work roll (4) during the first extraction step (El) and the passage of the coupling head (8) from the first retracted position (PI) to the second position deployed (P2),

- Exert a traction force on the working cylinder during the passage of the coupling head (8) of the second deployed position (P2) to the first retracted position (PI).

4. Method according to claims 2 and 3, wherein the hooking and the stall between, on the one hand, the hook (81) of the first coupling means of the coupling head (8), and secondly , and the corresponding hook (42) of the working cylinder lower (4) are caused by the movements of the carriage (20), in a direction perpendicular to the support rails (R3 \ R4 ').

5. Method according to one of claims 1 to 4, wherein the second coupling means (82, 83) comprise at least one movable member (82), articulated to the frame of the coupling head, suitable for cooperating with the pushing with the chock (60) of the lower support cylinder (6), which:

- In the retracted state of the second coupling means, the at least one movable element (82) is raised and locked in a retracted position (P3) where said movable element (82) does not engage with the chock (60), of the lower support cylinder (6), motor side,

in the deployed state, the second coupling means is in an extended position (P4) in which the said movable element (82) projects downwards under the action of gravity,

and wherein said movable member (82) is configured in said extended position (P4) to engage with a protruding portion (62) on the upper face the chock (60) of the lower backing roll (6) on the motor side,

and wherein:

during said return step (E2) of the coupling head, said passage of the coupling head (8) from the second deployed position (P2) to the first retracted position (PI) causes the engagement of the protruding portion (62) against the movable member (82), which pivots about its hinge under the action of the projecting portion (62), to escape said projecting portion (62), before returning, under the effect of gravity, in a position in which said movable member (82) projects downwardly on the other side of the projecting portion (62);

during the second extraction step (E3), said movable element (82) abuts against said projecting part (82), on the other side of the projecting part, under the thrust action of the actuator and so as to allow the output of said lower support cylinder (6).

6. Method according to one of claims 1 to 5, wherein the second coupling means comprise at least one foldable element (83) suitable for cooperating with the traction with the chock (60) of the lower support cylinder (6). ), who

in said extended position (P5) of said folding element, it is possible to engage in abutment with the chock (60) on the motor side of the lower support cylinder (6) to exert traction, allowing insertion of the support cylinder lower (6) and of said support equipment (13) during said insertion step (E5),

- In the folded position (P6) of said folding element (83), allows, successively to said third extraction step (E7) to uncouple the coupling head of said lower bearing cylinder (6) extracted from the holding cage during the return movement of the coupling head from the second extended position (P2) to the first retracted position (PI).

7. Installation (1) of rolling exhibiting

rolling mill comprising:

a cage (2) for holding,

a set of superimposed cylinders with substantially parallel axes comprising two lower and upper working rolls (3,4) defining the passing air gap, and two respectively upper and lower bearing rolls (5,6) intended to take respectively support on the working cylinders on the opposite side to that of the passage gap,

each cylinder having two rotatably mounted ends, each on a bearing carried by a chock (30, 40, 50, 60),

- A clamping system (9) of the chocks of the rolls, ensuring the locking of the chocks with respect to the holding cage, along the axis of the cylinder, while allowing the sliding chocks along the guide means, according to the plan Clamping, - Motorization means (10) of the support rollers, one side of the roll stand,

- a coupling head (8) integral with said actuator (70), located in the open position of the holding cage (2), at an intermediate height level between the lower working cylinder (4) and the cylinder of lower support (6), movable in a direction parallel to the rolls (3, 4, 5, 6), from a first retracted position (PI) for which the coupling head is located on the engine side to a second deployed position ( P2) for which the coupling head (8) having passed through the holding cage (2) is located on the operator side, said coupling head (8) comprising

first coupling means configured to drive the chock (40) or the end of the lower working roll, on the side of the motorization means of the rolling mill,

second coupling means configured to drive the chock (60) of the lower support roll (6), on the motorization side of the rolling mill, having a retracted state in which they do not cause the chock of the lower support roll (6) and an expanded state in which they push the chock (60) of said lower backing roll (6), and wherein the chocks (30, 40) of the upper and lower work rolls have means link (11), on the operator side, opposite the drive means, providing a mechanical connection (12) between these chocks on the operator side, and wherein the first coupling means and the second coupling means of said extraction system are configured to allow:

the successive extractions of the working rolls (3, 4) and then the support rolls (5, 6) out of the holding cage (2), the successive insertions of the support cylinders (5, 6) and then the work rolls (3, 4) in the holding cage (2),

and wherein the second coupling means comprise at least one movable element (82), articulated to the frame of the coupling head, suitable for cooperating with the thrust with the chock (60) of the lower support cylinder (6). , who :

in said retracted state of the second coupling means, said at least one movable element (82) is raised and locked in a retracted position (P3) where said movable element (82) does not engage with the chock (60), lower support cylinder (6), motor side of the rolling mill,

in said deployed state, second coupling means is in an extended position (P4) in which said movable element (82) projects downwards under the action of gravity,

and wherein said movable member (82) is a manually operated member for moving from the retracted position (P3) to the deployed position (P4) of said movable member (82), or vice versa, said movable member (82) being configured in said extended position (P4) for engaging with a projecting portion (62) on the upper face of the chock (60) of the lower support cylinder (6) motor side, present in the holding cage, and in such a way as to what:

- Said passage of the coupling head (8) of the second extended position (P2) to the first retracted position (PI) causes the engagement of the projecting portion (62) against the movable member (82), which pivots around its articulation under the action of the projection (62), to escape said projecting portion (62), before returning, under the effect of gravity, in a position where said movable member (82) projects downwards on the other side of the projecting portion (62);

said moving element (82), then in position on the other side of the projecting portion (62) abuts against said projecting part (82) under the thrust action of the actuator and in order to allow the exit said lower support cylinder (6).

8. Installation according to claim 7, wherein:

- The holding cage (2) of the rolling mill comprises support rails (R3, R4) on which rest the chocks (30, 40) of the upper and lower work rolls. (3,4), in the open position of the holding cage (2), said support rails (R3, R4) guiding the working rolls (3,4) and their chocks (30,40) during the extraction of the cylinders in said holding cage,

said rolling installation comprising a carriage (20) comprising support rails (R3 \ R4 ') suitable for supporting and guiding the chocks

(30, 40) of the lower and upper working rolls (3,4), which, in a relative position of the carriage with respect to the rolling mill, extend the support rails (R3, R4) of the rolling mill and in such a way that the lower and upper work rolls are loaded on the carriage (20) during the actuator pushing action on the work rolls (3,4).

9. Installation according to claim 7 or 8, wherein the first coupling means (81) comprise a hook rigidly secured to the coupling head (8) intended to engage with a corresponding hook (42) integral with one of ends of the lower work roll (4), and suitable for:

- exerting a thrust force on the lower work roll (4) during the pushing action of the coupling head (8) from the first retracted position (PI) to the second deployed position (P2),

- Trying on the lower work roll (4) during the passage of the coupling head (8) of the second deployed position (P2) to the first retracted position (PI).

10. Installation according to claims 8 and 9, wherein the hooking and unhitching between, on the one hand, the hook of the first coupling means (81) of the coupling head (8), and secondly , the corresponding hook (42) of the lower work roll (4) is caused by the movements of the carriage (20) in a direction perpendicular to the support rails (R3 ', R4').

11. Installation according to one of claims 7 to 10, wherein the second coupling means comprise at least one folding element (83) adapted to cooperate with the traction chock (60) of the lower support cylinder (6). motor side, which: in said extended position (P5) of said folding element, it is possible to engage in abutment with the chock (60) on the motor side of the lower support cylinder (6) to exert traction, allowing insertion of the support cylinder lower (6) in the roll stand,

- In the folded position (P6) of said folding element (83), allows to decouple the coupling head of said lower support cylinder (6) extracted from the holding cage, during the return movement of the head of coupling the second deployed position (P2) to the first retracted position (PI).

12. Installation according to claim 11 wherein said folding element (83) is a manually operated member to move from the extended position (P5) to the folded position (P6) of said folding member (83), or vice versa.

13. Installation according to one of claims 1 to 12, wherein the chocks on the operator side of the working rollers having sliding plates (31,41), parallel and distributed on either side of the axis of the cylinder, intended to cooperate with sliding plates (27) integral with two posts on the operator side of the rolling mill, the connecting means (11) comprise at least one blade (15) whose proximal end is integral with one of the lower chocks or upper, received in a lateral groove, formed in the body of the chock, on the back of a sliding plate, and whose distal end (16) enters a groove of the other chock, at least in one position deployed from said blade, in said open position of the holding cage.