Rolling equipment

Abstract

The invention relates to a rolling mill (1) having at least one upper and lower working roll (3, 4) and at least one upper and lower support roll (5, 6), wherein the working rolls (3, 4) and the support rolls (5, 6) are supported in a common rolling mill stand (2), the working rolls (3, 4) can be moved relative to each other to adjust a predetermined roll gap (7), and the working rolls (3, 4) are each operatively connected to at least one bending device, wherein at least one first bending device is associated with the upper working roll (4) and at least one second bending device is associated with the lower working roll (3), the second bending device comprising a bending cylinder (14) which is arranged in a vertically fixed position and by means of the first bending device the upper working roll (4) can be readjusted or guided along with the vertical adjustment of the height (8) of the roll gap (7). The rolling mill (1) is characterized in that the first bending device comprises a bending arm (16) which interacts with the fixed bending cylinder (15).

Description

Technical Field

[0001] The present invention relates to a rolling mill having at least one upper working roll and a lower working roll and at least one upper support roll and a lower support roll, wherein the working rolls and the support rolls are supported in a common rolling mill stand, the working rolls can be moved relative to each other to adjust a preset roll gap, and the working rolls are respectively effectively connected to at least one bending device, wherein at least one first bending device is associated with the upper working roll and at least one second bending device is associated with the lower working roll, the second bending device includes a bending cylinder, which is arranged in a vertically fixed position, and the upper working roll can be readjusted or guided together with the vertical adjustment of the height of the roll gap by means of the first bending device. Background Art

[0002] A rolling mill of the type described above is known, for example, from EP 2 342 026 B1. EP 2 342 026 B1 describes a rolling mill having work roll cylinders, bending cylinders, and balancing cylinders. The bending cylinders for the lower work rolls are arranged vertically in a fixed block. The bending device for the upper work rolls is characterized by a bending arm that is vertically movable in a guide on the roll support. The bending cylinders are guided within a window in the roll support, below their crossheads on the balancing arms of the upper support rolls, via a crossbeam on the balancing arms. In other words, the bending cylinders move together with the balancing arms when positioning the upper rolls. The bending arms, which are mounted in the crossbeams, apply vertical force to the inserts of the upper work rolls. This rolling mill provides a work roll axial displacement and bending device that allows very high roll lifts of up to approximately 1,100 mm.

[0003] However, the work roll axial displacement and bending device described in EP 2 342 026 B1 has the following disadvantage: when operating the upper bending cylinder to influence the roll gap profile, it causes interaction with the upper support roll balancing device. At least the cylinders of the upper support roll balancing device must be significantly stronger to avoid negatively affecting the roll gap profile. Components arranged in the power flow with the upper support roll balancing device must be designed to absorb the relatively high forces.

[0004] JPS5680308 A discloses a rolling mill 1 having at least one upper working roll and a lower working roll and at least one upper support roll and a lower support roll, wherein the working rolls and the support rolls are supported in a common rolling mill stand, the working rolls can be moved relative to each other to adjust a preset roll gap, and the working rolls are respectively effectively connected to at least one bending device, wherein at least one first bending device is associated with the upper working roll and at least one second bending device is associated with the lower working roll, the second bending device includes a bending cylinder, which is arranged in a vertically fixed position, and the upper working roll can be readjusted or guided together with the vertical adjustment of the roll gap height by means of the first bending device, wherein the first bending device has a bending cylinder arranged in a fixed position.

[0005] Further prior art is known from the documents JPS 6099405 A and JPS 59130607, DE 39 18242 A1, DE 1002005 042069 A1 and JP 2012143790. Summary of the Invention

[0006] The object of the present invention is to provide a rolling mill stand of the type mentioned in the introduction that allows very high roll lifts while avoiding undesirable interactions with the backup roll balancing devices. In particular, the invention is based on the object of implementing a work roll bending system in a rolling mill stand of the type mentioned in the introduction that allows for good guidance of the work roll inserts in the support windows for both the largest and smallest roll diameters and for both the largest and smallest roll lifts. In particular, the aforementioned advantages should also be achievable in rolling mills having a work roll axial displacement system.

[0007] 18. The roll forming machine according to claim 17, wherein the rollers are arranged on a roller frame and a support frame and the rollers are arranged on a roller frame. The rollers are arranged on a roller frame and a support frame and the rollers are arranged on a roller frame. The rollers are arranged on a roller frame and a support frame and the rollers are arranged on a roller frame. The rollers are arranged on a roller frame and a support frame and the rollers are arranged on a roller frame. The rollers are arranged on a roller frame and a support frame and the rollers are arranged on a roller frame. The rollers are arranged on a roller frame and a support frame and the rollers are arranged on a roller frame. The rollers are arranged on a roller frame and a support frame and the rollers are arranged on a roller frame. The rollers are arranged on a roller frame and a support frame and the rollers are arranged on a roller frame. The rollers are arranged on a roller frame and a support frame and the rollers are arranged on a roller frame. The rollers are arranged on a roller frame and a support frame and the rollers are arranged on a roller frame. The rollers are arranged on a roller frame and a support frame and the rollers are arranged on a roller frame. The rollers are arranged on a roller frame and a support frame and the rollers are arranged on a roller frame. The rollers are arranged on a roller frame and a support frame and the rollers are arranged on a roller frame. The rollers are arranged on a roller frame and a support frame and the rollers are arranged on a roller frame.

[0008] According to the present invention, a rolling mill is provided, comprising at least one upper working roll and a lower working roll, and at least one upper support roll and a lower support roll, wherein the working rolls and the support rolls are supported in a common rolling mill stand, the working rolls can be moved relative to each other to adjust a predetermined roll gap, and the working rolls are each operatively connected to at least one bending device, wherein a first bending device is associated with the upper working roll and a second bending device is associated with the lower working roll, the second bending device comprising a bending cylinder which is arranged in a vertically fixed position, and wherein the upper working roll can be readjusted or driven by means of the first bending device to vertically adjust the height of the roll gap. The rolling mill according to the invention is particularly characterized in that the first bending device comprises a bending arm which interacts with the fixed bending cylinder.

[0009] The bending arm in the present invention is understood to be a connecting element that bridges the spatial separation between the bending cylinder and the point of action of the bending force on the work roll insert. The structural and spatial separation of the first and second bending devices allows for particularly large roll lifts of at least 900 mm, preferably 1200 mm, and particularly preferably 1350 mm.

[0010] To move the upper work roll when adjusting the roll gap, the stroke of the first bending device follows the travel path of the vertical adjustment of the roll gap height, ensuring contact between the upper work roll and the upper support roll during the rolling process. The first bending device is structurally separate from the roll adjustment device.

[0011] According to the present invention, the bending device for the upper work roll is essentially decoupled from the balancing system for the upper support roll. Since the bending cylinder of the first bending device is vertically fixed and preferably arranged significantly above the work roll insert, a relatively high roll lift is ensured while the work roll insert is well guided in the support window. This decoupling simplifies accessibility of both devices for maintenance purposes.

[0012] Advantageously, provision is made for the bending arm of the first bending device to drive the upper working roll when the height of the roll gap is adjusted vertically.

[0013] The height of the roll gap is pre-adjusted before the start of rolling (a rolling pass). To this end, the upper roll adjustment device moves the upper support roll into a position where it is held against gravity by a support roll balancing device. The upper work roll, held by the arms of the bending device, follows this vertical movement. The bending cylinder, and therefore the upper work roll, initially follows the movement of the upper support roll between rolling passes. The additional stroke of the bending cylinder causes the work roll to bend, thereby influencing the roll gap profile in the desired manner during the pass.

[0014] In a preferred embodiment of the rolling mill according to the invention, it is provided that the working rolls are adjustable axially and vertically.

[0015] The stationary mounting of the bending cylinders of the upper first bending device is advantageous in particular in conjunction with the axial displacement of the working rolls, since in this arrangement the structurally and spatially separated backup roll balancing devices are not additionally loaded with reaction forces caused by the bending of the working rolls.

[0016] Preferably, at least one axial displacement device is provided for at least one working roll. The axial displacement device, for example the axial displacement device of the upper working roll, can be arranged in a fixed position on the roll support or in a floating manner.

[0017] In an advantageous variant of the rolling mill according to the invention, at least one axial displacement device is operatively connected to the bending arm of the first bending device. The operative connection can be achieved via a direct connection between the bending arm and the axial displacement device. An indirect connection, for example, via additional locking pins or guides, also ensures the operative connection.

[0018] The bending cylinders of the second bending device can be arranged vertically in a stationary block and act on the work roll insert of the lower work roll.

[0019] In an advantageous variant of the rolling mill according to the invention, the bending cylinders of the second bending mill are arranged in a thickening of the roll supports of the rolling mill stand.

[0020] According to the invention, the bending cylinders of the first bending device, i.e., the bending device that drives the upper roll arrangement (upper work roll and upper backup roll), are each supported on the upper crosshead of the roll support of the rolling mill stand. This high arrangement of the bending cylinders ensures a relatively large adjustment path for the upper roll arrangement.

[0021] For example, the bending cylinders of the first bending device can be sunk into a recess in the upper crosshead of the roll support of the rolling stand.

[0022] Alternatively, the bending cylinders of the first bending device can each be fastened to the outside of the roll supports of the rolling stand.

[0023] Preferably, the bending arms of the first bending device are guided vertically by means of guide elements in recesses of the roll stand, preferably in each case in a bearing window of the roll bearing.

[0024] The bending arm of the first bending device can engage from below the working roll insert of the upper working roll at the end of a correspondingly designed thickening by means of the thickening.

[0025] Alternatively, it can be provided that the bending arm of the first bending device is provided with a recess which completely surrounds the corresponding contour of the work roll insert engaging the upper work roll. In this way, positive and negative work roll bending can be achieved.

[0026] In the rolling mill according to the invention, the upper support rollers are each supported at their ends in a support roller insert, and the support roller insert is operatively connected to a compensating cylinder which compensates for the deadweight of the support rollers. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The present invention will be explained below based on a plurality of embodiments with reference to the accompanying drawings.

[0028] The accompanying drawings show:

[0029] Figure 1 shows a longitudinal section of a rolling mill according to a first embodiment of the invention, the rolling mill having a working roll pair and a backup roll pair,

[0030] Figure 2 Shown along Figure 1 A cross section along the line BB in FIG. 1 , which shows a first variant of the axial displacement device for the upper working roll,

[0031] Figure 3 Shown corresponding to Figure 2 , which shows a second variant of the axial displacement device for the upper working roll,

[0032] Figure 4 shows a longitudinal section through a rolling plant according to a second embodiment of the invention,

[0033] Figure 5 Shows penetration Figure 4 A cross section of the upper crosshead of the roll support of the rolling mill in FIG. 1 , which illustrates an alternative design for fixing the bending cylinder of the upper bending mill; and

[0034] Figure 6 Shown along Figure 4 The cross section of line BB in . DETAILED DESCRIPTION

[0035] First reference Figure 1 . Figure 1A rolling mill 1 according to the invention is shown. The rolling mill 1 comprises a rolling stand 2 having two working rolls 3 and 4 and two backup rolls 5 and 6. The rolling stand 2 described in the exemplary embodiment is designed as a four-roll stand, but it can also have a different configuration. A roll gap 7 is formed between the working rolls 3 and 4, into which the rolled product is drawn during operation of the rolling mill 1. In the rolling mill 1 according to the invention, the height 8 of the roll gap 7, also known as the roll lift, is adjustable, specifically via an upper roll adjustment device 28 and, if appropriate, a lower roll adjustment device (not shown). Furthermore, the working rolls 3 and 4 can also be axially displaced, as described below, so that the profile of the roll gap 6 can be influenced by axially displacing the working rolls 3 and 4 relative to one another.

[0036] The working rolls 3, 4 and the backup rolls 5, 6 are held in a rolling mill stand 2, which includes two roll supports 31, one on the operating side and one on the drive side. The roll supports 31 are designed as closed frames in which all rolling forces are balanced via internal forces. The rolling mill stand 2 accommodates backup roll inserts 9, 10 and working roll inserts 11, 12, each of which is displaceably arranged within a window 32 formed by the roll supports. The backup roll inserts 9, 10 support the lower backup roll 5 and the upper backup roll 6. The backup roll insert 10 shown in the figure supports the upper backup roll 6, while the backup roll insert 9 supports the lower backup roll 5.

[0037] The work roll mountings 11 and 12 are arranged between the backup roll mountings 9 and 10, and the work rolls 3 and 4 are supported in the work roll mountings. The upper work roll mounting 12 supports the upper work roll 4, while the lower work roll mounting 11 supports the lower work roll 3.

[0038] The work roll insert 11 that accommodates the lower work roll 3 is displaceably arranged in a fixed block 13. The block 13 accommodates a bending cylinder 14, around which the lower work roll 3 can be bent. The bending cylinder 14, which acts on the work roll insert 11 for the lower work roll 3, is part of a lower, second bending device. Instead of a block, the rolling mill stand 2 can also have a thickened portion (not shown) for accommodating the bending cylinder 14.

[0039] A balancing arm 33 acts on the support roller insert 10 for the upper support roller 6, via which the deadweight of the support roller and its insert 6 can be compensated with the aid of a balancing cylinder (not shown). For this purpose, the balancing arm 33 is equipped with a hook-shaped thickening that engages a corresponding projection of the support roller insert 10 from below.

[0040] The work roll bending and / or work roll balancing of the upper work roll 4 is achieved via a bending cylinder 15, which is operatively connected to the upper work roll 4 via a bending arm 16. The bending cylinder 15 and the bending arm 16 are part of the upper first bending device. The bending cylinder 15 is fixedly mounted on or supported on the upper crosshead 34 of the roll support 2 and extends through a recess 35 of the roll support 2. The bending cylinder 15 extends essentially vertically. In its extension, a bending arm 16 is attached to the bending cylinder, each having a thickened portion 17 at its lower end. The thickened portion 17 of the bending arm 16 engages from below with a lateral, ear-shaped projection of the work roll insert 12 of the upper work roll 4.

[0041] The bending cylinder is preferably designed for a large stroke which exceeds the roller wear plus the roller lifting stroke.

[0042] The bending arm 16 is guided vertically by means of a guide element 18 in a recess 36 of the rolling stand 2 or of a roll support 31 of the rolling stand 2. When the height 8 of the roll gap 7 is adjusted, the upper working roll 4 and the upper backup roll 6 are carried along by the bending arm 16, which engages the work roll insert 12 from below with its thickened portion 17.

[0043] The bending cylinders 14, 15 act on the outer edge areas of the working rolls 3, 4 and thus exert a force directed vertically outward from the roll gap 7 in the edge areas of the working rolls 3, 4, which corresponds to the force of the rolled material acting in the middle area of ​​the working rolls 3, so as to counteract the bending and separation of the working rolls 3, 4 caused by the rolled material.

[0044] Bending cylinders 14, 15 in the present invention Figure 1 In the first embodiment shown in FIG, a so-called positive working roll bending is realized. In order to increase the adjustment range for contour influencing by so-called negative working roll bending, additional piston-cylinder systems 19, 20 are provided, each of which acts vertically.

[0045] Figure 4 A second embodiment of a rolling mill 1 according to the invention is shown. Identical components are provided with the same reference numerals. Figure 1 In contrast to the exemplary embodiment of , here the bending cylinder 15 of the upper first bending device is partially sunk from below in the upper region of the window 32 into the arrow-shaped recess 35 of the upper crosshead 34 of the rolling stand 2 .

[0046] In addition, according to Figure 4 The embodiments of the present invention are different from those according to Figure 1The embodiment of the present invention differs from the embodiment of the present invention in that a window-like recess 36 is provided in the bending arm 16, into which a correspondingly designed strip 37 of the work roll insert 12 for the upper work roll 4 engages. As a result, the work roll insert 12 for the upper work roll 4 is fixed in vertically opposite directions, so that the upper work roll 4 can be bent in positive and negative directions by means of the bending cylinder 15.

[0047] Figure 5 An alternative variant of the stationary fastening of the bending cylinders 15 to the rolling stand 2 is shown. In this case, a plurality of bending cylinders 15 are arranged outside the roll supports 31 of the rolling stand 2 and each act on an extension 30 of a bending arm 16 .

[0048] The rolling mill 1 according to the invention also comprises axial displacement devices 21 , which are respectively arranged at the outer edge region of the working rolls 3 , 4 .

[0049] The axial displacement device 21 for axially displacing the work rolls 3 and 4 is located on the work roll housings 11 and 12 on the operator side and comprises a hydraulically operable piston-cylinder unit. The pistons of the piston-cylinder units are each connected to a retaining arm 24 guided in the corresponding housing. Locking devices, located on the outside of the two shanks of the roll support 31 on the operator side, prevent horizontal movement of the retaining arm 24 and, consequently, axial movement of the piston 22 of the piston-cylinder unit during rolling operation. Axial displacement of the work rolls 3 and 4 supported in the work roll housings 11 and 2 is achieved by applying pressure to the piston or rod side of the piston-cylinder unit.

[0050] Figure 2 Shown along Figure 4 The line BB in the middle runs through Figure 4 A cross-section through a rolling mill 1 illustrates the structure of the axial displacement device 21 and its interaction with the upper work roll 4. The axial displacement device 21 comprises at least one hydraulically-acting piston 22, which is mounted on a retaining arm 24 via a thrust bearing 25. The retaining arm 24 is arranged in a horizontally sliding manner in the work roll housings 11, 12 and is engaged by a lateral retaining device 29, which is fixed to the outside of the rolling mill stand 2 and prevents horizontal movement of the retaining arm 24 in the direction of the roll axis 23. The piston 22 of the axial displacement device 21 is thereby also fixed in the axial direction. The retaining arm 24 is vertically movable in the lateral retaining device 29.

[0051] The interaction of the contoured outer guide element 18 of the bending arm with the correspondingly configured guide groove 38 of the roller support 31 or the shaft of the roller support 31 can also be seen from the Figure 2 As seen in the cross section shown.

[0052] Figure 3An alternative design of the axial displacement device 21 is shown. Figure 3 The same reference numerals are provided in the figures. Figure 3 The axial displacement device 21 and Figure 2 The axial displacement device shown differs in that the holding device 29 is fastened to the bending arm 16 and is therefore entrained when the height 8 of the roller gap 7 is adjusted.

[0053] Figure 6 An alternative embodiment of guiding the bending arm 16 in the rolling stand is shown. The bending arm 16 is provided on its side facing the shaft of the roll support 31 with a guide groove 38 which surrounds a corresponding guide contour 39 of the shaft of the roll support 31 .

[0054] Reference Signs List

[0055] 1 Rolling equipment

[0056] 2 rolling mill stands

[0057] 3 Lower working roll

[0058] 4 Upper working roll

[0059] 5 Lower support roller

[0060] 6 Upper support roller

[0061] 7 Roller gap

[0062] 8 Roller gap height

[0063] 9 Support roller insert

[0064] 10 Support roller insert

[0065] 11 Working roll insert

[0066] 12 Work roll inserts

[0067] 13 Bending Block

[0068] 14 Bending cylinder of lower working roll

[0069] 15 Bending cylinder of upper working roll

[0070] 16 Bend Arm

[0071] 17 Thickened portion of the bending arm

[0072] 18 Guide element

[0073] 19 Piston-cylinder system

[0074] 20 piston cylinder system

[0075] 21 Axial displacement device

[0076] 22 piston

[0077] 23 Axis of working roll

[0078] 24 Holding Arm

[0079] 25 thrust bearing

[0080] 26 bearings

[0081] 27 cylinder housing

[0082] 28 Upper roller adjustment device

[0083] 29 Lateral holding device

[0084] 30 Extension of the bending arm

[0085] 31 Roller support

[0086] 32 windows

[0087] 33 Balance arm for upper support roller

[0088] 34 Crosshead

[0089] 35 Crosshead recess

[0090] 36 Recessed portion of roller support

[0091] 37 laths

[0092] 38 guide slots

[0093] 39 Guide Profile

Claims

1. A rolling mill (1) comprising at least one upper working roll and a lower working roll (3, 4) and at least one upper support roll and a lower support roll (5, 6), wherein the working rolls (3, 4) and the support rolls (5, 6) are supported in a common rolling mill stand (2), the working rolls (3, 4) being able to be moved relative to each other to adjust a predetermined roll gap (7), and the working rolls (3, 4) are each effectively connected to at least one bending device, wherein at least one first bending device is associated with the upper working roll (4) and at least one second bending device is associated with the lower working roll (3), the second bending device comprising a bending cylinder (14) which is arranged in a vertically fixed position and wherein the upper working roll (4) can be readjusted or guided together with the first bending device as the height (8) of the roll gap (7) is vertically adjusted, wherein The first bending device comprises a bending arm (16) cooperating with a bending cylinder (15) arranged in a fixed position, characterized in that the bending cylinder (15) of the first bending device is supported at the upper crosshead (34) of the roll support (31) of the rolling mill stand (2), and is provided with at least one axial displacement device (21) for at least one of the working rolls (3, 4), and the at least one axial displacement device (21) is effectively connected to the bending arm (16) of the first bending device.

2. The rolling equipment according to claim 1, characterized in that When the height (8) of the roll gap (7) is adjusted, the bending arm (16) of the first bending device drives the upper working roll (4).

3. The rolling equipment according to claim 1 or 2, characterized in that The working rolls (3, 4) are adjustable axially and vertically.

4. The rolling equipment according to claim 1 or 2, characterized in that The bending cylinder (14) of the second bending device is arranged vertically in a stationary block (13) and acts on the working roll insert (11) of the lower working roll (3).

5. The rolling equipment according to claim 1 or 2, characterized in that: The bending cylinder (14) of the second bending device is arranged in a thickened portion of a roll support (31) of the rolling mill stand (2).

6. The rolling equipment according to claim 1 or 2, characterized in that The bending cylinder (15) of the first bending device is sunk into a recess (35) of the upper crosshead of the roll support (31) of the rolling mill stand (2).

7. The rolling equipment according to claim 1 or 2, characterized in that The bending cylinders (15) of the first bending device are respectively fixed on the outer side surfaces of the roller supports (31) of the rolling mill stand (2).

8. The rolling equipment according to claim 1 or 2, characterized in that The bending arm (16) of the first bending device engages the work roll insert (12) of the upper work roll from below at the end of the thickening by means of a correspondingly designed thickening (17).

9. The rolling equipment according to claim 1 or 2, characterized in that: The bending arm (16) of the first bending device is provided with a recess (36) which surrounds a corresponding contour of a work roll insert (12) engaging the upper work roll (4).

10. The rolling equipment according to claim 1 or 2, characterized in that The upper support rollers (6) are supported at their ends in support roller inserts (10), and the support roller inserts (10) are operatively connected to balancing cylinders which compensate for the deadweight of the support rollers (6).

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