Rolling mill provided with at least one cooling nozzle

Abstract

Rolling mill (1) includes: side bearing rollers (5), able to laterally support the working rollers (2) of the rolling mill, with each side bearing roller being carried by a support arm (6), mounted pivoting on an axis (7), load distribution beams (8) extending between the corresponding posts of each pair, and elements (9) for applying a preload force on each support arm (6), intended to engage with one of the support arms on a bearing surface (10), and including at least one preload cylinder (11) integral with one of the load distribution beams (8), one or several spraying nozzles for a lubricant/cooling fluid, at least one of the nozzles (12, 12), is embedded on one of the support arms (6) and the fluid supply circuit of the at least one nozzle (12, 12) includes a connection/disconnection device (13) with the support arm (6).

Claims

1. A rolling mill (1) comprising: a retaining stand (30) comprising two pairs of posts (31) separated from each other at two ends of the stand, at least two posts of one pair defining an access window, two working rollers (2), able to surround a strip to be rolled, two bearing rollers (4), and two intermediate rollers (3), the bearing rollers (4) and the intermediate rollers (3) being mounted rotating at ends thereof on chocks, side bearing rollers (5), able to laterally support the working rollers (2), with each side bearing roller being carried by a support arm (6), mounted pivoting on an axis (7), load distribution beams (8) extending between corresponding posts of each pair, and means (9) for applying a preload force on each support arm (6), intended to engage with one of the support arms on a bearing surface (10), and comprising at least one preload cylinder (11) integral with one of the load distribution beams (8), one or more spraying nozzles for providing a stream or streams of a lubricant/cooling fluid, wherein at least one of the nozzles (12, 12), is embedded on one of the support arms (6) and a fluid supply circuit of said at least one nozzle (12, 12) comprises a connection/disconnection device (13) comprising: a duct (14) of the support arm (6), intended to channel the fluid, having a supply opening (15) exiting on the bearing surface of the support arm intended to engage the means (9) for applying a preload force, a hollow portion (16), mobile in relation to the load distribution beam (8), which is moveable in relation to said load distribution beam (8) under action of said means (9) for applying a preload force, able to form a sealed connection with the supply opening (15) on the bearing surface (10) in a first position of connection, and retractable into a second position of disconnection, at a distance from the bearing surface (10).

2. The rolling mill according to claim 1, wherein the hollow portion (16) is moveable in translation, according to a substantially horizontal direction, under action of said means (9) for applying a preload force, a support element (17) being provided sliding in relation to said load distribution beam (8), a ball-and-socket connection being provided between the hollow portion (16) and said support element (17).

3. The rolling mill according to claim 2, wherein the hollow portion (16) comprises a contact surface (18) intended to form a sealed connection with the bearing surface (10), as well as a hemispherical surface (19) intended to cooperate with a complementary recess (20) of the support element, in order to constitute the ball-and-socket connection.

4. The rolling mill according to claim 3, wherein the hemispherical surface (19) is stressed towards the complementary recess (20) by means of a flexible pipe (21) that has bellows (22), mounted in tension between the hollow portion (16) and the support element (17).

5. The rolling mill according to claim 1, wherein the fluid supply circuit of said at least one nozzle (12, 12) comprises a hose (23) between the support element (17), mobile, and a source of lubricant/cooling fluid.

6. The rolling mill according to claim 1, wherein each support arm (6) of a side bearing roller (5) is mounted pivoting on said axis (7), constituted by a shaft integral with the chocks of one of the intermediate rollers (3), with each intermediate roller (3), chocks of the intermediate roller, side bearing rollers (5) and corresponding support arms (6) forming a self-bearing unit, called an insert, which can be removed or introduced by sliding through the access window during maintenance.

7. The rolling mill according to claim 6, wherein each side bearing roller (5) is supported by bearing roller wheels, with the bearing roller wheels being mounted on axes (50, 51) of the support arms (6) by an intermediary of bearings, and wherein the support arm (6) comprises a supply circuit of lubricant for the bearings, separate from the fluid supply circuit of said at least one nozzle (12, 12).

8. The rolling mill according to claim 7, wherein the supply circuit of lubricant for the bearings comprises the shaft whereon is mounted pivoting the support arm (6), said shaft being hollow.

9. The rolling mill according to claim 1, wherein said at least one nozzle (12) is directed in such a way that the stream of lubricant/cooling fluid is directed on the intermediate roller (3), in the vicinity of a contact zone (Z) between the working roller (2) and the intermediate roller (3), and in such a way that driven by the intermediate roller, the fluid of the stream reaches the working roller (2).

10. The rolling mill according to claim 1, wherein said at least one nozzle (12) is directed in such a way that the stream of lubricant/cooling fluid is directed directly on the strip to be rolled and in such a way that the stream of lubricant/cooling fluid slides on the strip to be rolled in a direction of the corresponding working roller (2).

11. A method for cooling a rolling mill according to claim 10, wherein the working roller is sprayed by a stream from at least one nozzle (12), with the stream of the nozzle being powerful enough to reach said working roller (2) by sliding on the strip to be rolled (B), against a direction of scrolling of the strip to be rolled.

12. The rolling mill according to claim 2, wherein the fluid supply circuit of said at least one nozzle (12, 12) comprises a hose (23) between the support element (17), mobile, and a source of lubricant/cooling fluid.

13. The rolling mill according to claim 2, wherein each support arm (6) of a side bearing roller (5) is mounted pivoting on said axis (7), constituted by a shaft integral with the chocks of one of the intermediate rollers (3), with each intermediate roller (3), chocks of the intermediate roller, side bearing rollers (5) and corresponding support arms (6) forming a self-bearing unit, called an insert, which can be removed or introduced by sliding through the access window during maintenance.

14. The rolling mill according to claim 2, wherein said at least one nozzle (12) is directed in such a way that the stream of lubricant/cooling fluid is directed on the intermediate roller (3), in the vicinity of the contact zone (Z) between the working roller (2) and the intermediate roller (3), and in such a way that driven by the intermediate roller, the fluid of the stream reaches the working roller (2).

15. The rolling mill according to claim 2, wherein said at least one nozzle (12) is directed in such a way that the stream of lubricant/cooling fluid is directed directly on the strip to be rolled and in such a way that the stream of lubricant/cooling fluid slides on the strip to be rolled in a direction of the corresponding working roller (2).

16. The rolling mill according to claim 3, wherein the fluid supply circuit of said at least one nozzle (12, 12) comprises a hose (23) between the support element (17), mobile, and a source of lubricant/cooling fluid.

17. The rolling mill according to claim 3, wherein each support arm (6) of a side bearing roller (5) is mounted pivoting on said axis (7), constituted by a shaft integral with the chocks of one of the intermediate rollers (3), with each intermediate roller (3), chocks of the intermediate roller, side bearing rollers (5) and corresponding support arms (6) forming a self-bearing unit, called an insert, which can be removed or introduced by sliding through the access window during maintenance.

18. The rolling mill according to claim 3, wherein said at least one nozzle (12) is directed in such a way that the stream of lubricant/cooling fluid is directed on the intermediate roller (3), in the vicinity of the contact zone (Z) between the working roller (2) and the intermediate roller (3), and in such a way that driven by the intermediate roller, the fluid of the stream reaches the working roller (2).

19. The rolling mill according to claim 3, wherein said at least one nozzle (12) is directed in such a way that the stream of lubricant/cooling fluid is directed directly on the strip to be rolled and in such a way that the stream of lubricant/cooling fluid slides on the strip to be rolled in a direction of the corresponding working roller (2).

Description

(1) The invention shall be better understood when reading the following description, along with the annexed figures, among which:

(2) FIG. 1 is a partial view, of a rolling mill in accordance with the invention showing the upper portion of the rolling mill, and more particularly the bearing roller, the intermediate roller and the working roller, the side bearing rollers, as well as their support arm.

(3) FIG. 2 is a partial view, of detail, showing a connection/disconnection device in said first connection position of the device,

(4) FIG. 3 is a perspective view of the retaining stand, and more particularly of the possibility of adjusting between the load distribution beam in relation to the posts of the stand.

(5) Also the invention relates first of all to a rolling mill 1 comprising: a retaining stand 30 comprising two pairs of posts 31 separated from each other at the two ends of the stand, at least two posts of the same pair defining an access window, two working rollers 2, able to surround a strip to be rolled, two bearing rollers 4, and two intermediate rollers 3, the bearing rollers 4 and the intermediate rollers 3, being mounted rotating at their ends on chocks, side bearing rollers 5, able to laterally support the working rollers 2, each side bearing roller being carried by a support arm 6, mounted pivoting on an axis 7, load distribution beams 8 extending between the corresponding posts of each pair, and means 9 for applying a preload force on each support arm 6, intended to engage with one of the support arms on a bearing surface 10, and comprising at least one preload cylinder 11 integral with one of the load distribution beams 8, one or several spraying nozzles for a lubricant/cooling fluid.

(6) The working rollers 2, the intermediate rollers 3 and the bearing rollers 4 are substantially with parallel axes, with the axes of the rollers 2, 3, 4 being contained in a clamping plane substantially perpendicular to the strip to be rolled B. The two working rollers 2 are located on either side of the strip to be rolled, with their spacing defining the passage gap in operating. Each intermediate roller 3 is inserted between the working roller 2 and the corresponding bearing roller 4. The working roller is driven in rotation, indirectly by the putting into rotation of the intermediate roller 3.

(7) The side bearing rollers 5 are more preferably of a number of two per working roller 2 and make it possible to maintain the working roller 2, laterally of the two sides of the clamping plane. This is as such more preferably a reversible rolling mill. Each side bearing roller 5 is mounted on a support arm 6 mounted pivoting on an axis 7.

(8) According to an embodiment, each support arm 6 can be mounted pivoting on a shaft integral at its ends with the chocks of the intermediate rollers, such as taught by document U.S. Pat. No. 4,531,394 or document U.S. Pat. No. 6,041,636. In this rolling mill design, each intermediate roller 3, chocks of the intermediate roller, side bearing rollers 5 and corresponding support arms 6 form a self-bearing unit, commonly called insert or cassette, which can be removed or introduced by sliding through the access window during maintenance.

(9) Alternatively, and according to another embodiment taught by document WO 2011/107165 A1, each support arm 6 can be mounted pivoting on camber blocks, able to be moved vertically in relation to posts of the stand.

(10) The load distribution beams 8 extending between the corresponding posts of each pair, respectively facing each support arm, at least during operating. The means 9 for applying a preload force on each support arm 6 are intended to engage with one of the support arms on a bearing surface 10, and comprise at least one preload cylinder 11 integral with one of the load distribution beam 8. The position of the load distribution beam 8 can be adjusted horizontally in relation to the posts 31. To this effect, synchronised screw/nut actuators 81 can be provided, in order to approach the load distribution beam towards the support arm 6, or on the contrary separate the load distribution beam 8 from said support arm 6. In operating, the working roller is generally constrained to press the side bearing roller 5 upstream, according to the direction scrolling of the strip B. The load distribution beam 8, downstream, is positioned a few millimeters from the support arm 6, downstream. The means 9 for applying a preload force are then used to take up the slack and provide the contact with the side bearing roller 5, downstream.

(11) The rolling mill comprises said spraying nozzle or nozzles for a lubricant/cooling fluid, with these nozzles being in particular intended to cool/lubricant the working rollers, directly or indirectly and/or the other rollers of the rolling mill.

(12) According to the invention, at least one of the nozzles 12, 12 is embedded in one of the support arms 6, in particular to allow for the lubrication/cooling of the working rollers and/or of the intermediate rollers.

(13) Advantageously, the fluid supply circuit of said at least one nozzle 12, 12 comprises a connection/disconnection device 13 comprising: a duct 14 of the support arm 6, intended to channel the fluid, having a supply opening 15 exiting on the bearing surface 10 of the support arm 6 intended to engage the means 9 for applying a preload force, a hollow portion 16, mobile in relation to the load distribution beam, able to be moved in relation to said load distribution beam 8 under the action of said means 9 for applying a preload force.

(14) According to the invention, this hollow portion 16 is able to form a sealed connection with the supply opening 15 on the bearing surface 10 in a first position of connection, or on the contrary, retract into a second disconnection position, at a distance from the bearing surface 10.

(15) In the first connection position, such as shown in FIG. 2, the cooling fluid can be channelled from the source to said at least one nozzle referenced as 12 (shown) or to said at least one nozzle referenced as 12 (not shown), by the intermediary of said connection/disconnection device.

(16) In a second position of disconnection (not shown), the means 9 for applying a preload force are retracted, in retracted position, said hollow portion 16 being at a distance from the support arm 6. This position makes it possible, in particular when the design of the rolling mill is of the insert (or cassette) type to be able to remove or introduce the insert, without requiring additional maintenance time to disconnect/connect the source of fluid.

(17) Another advantage of such a connection/disconnection device is that it directly connects to the support arm, not to the chocks of the intermediate roller as taught in prior art known from document U.S. Pat. No. 6,041,636. In order to reach the nozzle 12 or 12, in a rolling mill of the insert type according to the invention, the fluid does not need to pass through the hollow shaft whereon the support arm is mounted pivoting. It is then possible to obtain flow of fluid that are much higher than those obtained in this prior art.

(18) In the invention, the hollow of the shaft can possibly be used, as in prior art to channel a fluid intended to lubricate the bearings of the roller wheels 52 laterally supporting the side bearing roller 5.

(19) Also and according to an embodiment, each side bearing roller 5 is supported by roller wheels 52, with the roller wheels 52 being mounted on axes 50, 51, parallel, of the support arm 6 by the intermediary of bearings. The support arm 6 comprises a circuit for supplying with lubricant for the bearings, separate from the supply circuit of said at least one nozzle 12, 12. The lubricant supply circuit for the bearings can comprise the shaft whereon is mounted pivoting the support arm 6, said shaft being hollow, with the lubricant passing through at least partially.

(20) According to an embodiment, shown in an unrestricted manner in FIG. 1, the hollow portion 16 can be moved in translation, according to a substantially horizontal direction, under the action of said means for applying a preload force, thanks to a support element 17 provided sliding in relation to said load distribution beam 8. This support element 17 can slide on a bore of the load distribution beam, under the action of the cylinder 11 which can be dual-effect. When the cylinder 11, is deployed, the support element 17 and the hollow portion 16 are jointly moved in the direction of the support arm 6. Inversely, when the cylinder 11 retracts, the support element 17 and the hollow portion 16 separate from the support arm 17.

(21) A ball-and-socket connection can be provided between the hollow portion 16 and said support element 17. This ball-and-socket connection makes it possible to provide that the contact surface 18 of the hollow portion 16, is inclined according to the plane of the bearing surface 10 of the support arm 6 in said connection position.

(22) For example, according to the embodiment shown, the ball-and-socket connection comprises a hemispherical surface 19 of the hollow portion intended to cooperate with a recess of complementary shape 20 of the support element 17.

(23) According to an embodiment, the hemispherical surface 19 is constrained towards the additional recess 20 by means of an elastic pipe 21 that has bellows 22, mounted in tension between the hollow portion 16 and the support element 17. This elastic pipe 17 makes it possible to maintain the hollow portion 16 on the support element 17. The bellows of the elastic pipe 21 provides the required elasticity so that the hollow portion 16 can pivot in the recess 20, according to a ball-and-socket connection.

(24) The supply circuit can include a hose 23 between the support element 17, mobile, and the source of the lubricant/cooling product. In operating, in said first position of connection, the fluid arrives from the source, passes through the hose 23 to a bore of the support element 17, then flows into the elastic pipe 21, through the hollow portion 16, to reach the supply opening 15. Starting from this opening, the fluid flows in the support arm 6 through the duct 14 to said at least one nozzle 12 which can be integral with the support of the roller wheels 52, or said at least one nozzle 12 which can be integral directly on the body of the support arm 6.

(25) Preferably, a plurality of nozzles 12 and/or 12 can be arranged over the length of the support arm 6 in such a way as to be able to cool the working roller and/or the intermediate roller over its entire length.

(26) Preferably, said at least one nozzle 12 can be directed in such a way that the stream is directed directly on the strip to be rolled, not directly on the working roller, and in such a way that the stream slides on the strip to be rolled in the direction of the working roller 2.

(27) Such an orientation of nozzles 12 makes it possible advantageously to effectively cool the working roller when the working roller and the intermediate roller are of small diameters and prohibit directly spraying the working roller.

(28) This orientation of said at least one nozzle 12 makes it possible to cool the working roller, even when the stream is sprayed against the direction of scrolling of the strip to be rolled, such as shown in FIG. 2. This is rendered possible in that said at least one nozzle 12, supported by the pivoting arm 6 is located in the vicinity of the working roller, and in that the invention makes it possible to obtain a substantial flow of fluid. This proximity and such flows allow the stream to slide on the strip against the direction of scrolling of the strip until reaching the working roller.

(29) Alternatively or additionally, said at least one nozzle 12 can be directed in such a way that the stream is directed on the intermediate roller 3, in the vicinity of the contact zone Z between the working roller 2 and the intermediate roller 3, and in such a way that driven by the intermediate roller, the fluid of the stream reaches the working roller 2.

(30) The invention as such makes it possible to place one or several nozzles 12 on the support arms 6, in the vicinity of this zone Z, and as such spray the intermediate roller 3, as close as possible to this zone, and not only on the bearing roller 4/intermediate roller 3 contact zone, such as is known in prior art. Contrary to the rolling mill of prior art, when the intermediate roller 3 is driven in rotation at a substantial speed, the major portion of the fluid of the stream reaches the working roller 2, regardless of the action of the centrifugal force.

(31) Such nozzles 12, 12 can be provided over all or a portion of the two support arms of the upper side bearing rollers and over all or a portion of the two support arms of the lower side bearing rollers.

(32) According to an advantageous embodiment, the nozzles 12, 12 are provided on the four support arms, with a connection/disconnection device being provided between each support arm and the corresponding load distribution beam.

(33) According to this last embodiment, the invention makes it possible to cool/lubricate: each of the two working rollers, upper and lower, on either side of the clamping plane of the rolling mill, each of the two intermediate rollers, upper and lower, and also, the intermediate rollers 3 and working rollers 2 contact zones, in particular on either side of the clamping plane of the rolling mill.

(34) Naturally, other embodiments could have been considered by those skilled in the art without however leaving the scope of the invention defined by the claims hereinafter.

NOMENCLATURE

(35) 1. Rolling mill, 2. Working roller, 3. Intermediate roller, 4. Bearing roller 5. Side bearing roller, 6. Support arm (Side bearing roller 5), 7. Pivoting axis (Support arm 6), 8. Load distribution beam, 9. Means for applying a preload force, 10. Bearing surface (Support arm 6), 11. Cylinder (Means for applying a preload force), 12. Spraying nozzles (on strip), 12. Spraying nozzles (on intermediate roller barrel), 13. Connection/disconnection device, 14. Duct (Support arm), 15. Supply opening, 16. Hollow portion, 17. Support element, 18. Contact surface (Hollow portion 16), 19. Hemispherical surface (Hollow portion 16), 20. Recess (Support element 17), 21. Elastic pipe, 22. Bellows, 23. Hose 30. Retaining stand, 31. Posts, 50, 51 Axes (support of the roller wheels), 52. Roller wheels, 81. Screw/nut actuators, B. Strip to be rolled, Z. Working roller 2/intermediate roller 3 contact zone.